Validation of the quantitative point-of-care CareStart biosensor for assessment of G6PD activity in venous blood.

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Germana Bancone

Full Text Available Glucose-6-phosphate dehydrogenase (G6PD deficiency is the most common enzymopathy in the human population affecting an estimated 8% of the world population, especially those living in areas of past and present malaria endemicity. Decreased G6PD enzymatic activity is associated with drug-induced hemolysis and increased risk of severe neonatal hyperbilirubinemia leading to brain damage. The G6PD gene is on the X chromosome therefore mutations cause enzymatic deficiency in hemizygote males and homozygote females while the majority of heterozygous females have an intermediate activity (between 30-80% of normal with a large distribution into the range of deficiency and normality. Current G6PD qualitative tests are unable to diagnose G6PD intermediate activities which could hinder wide use of 8-aminoquinolines for Plasmodium vivax elimination. The aim of the study was to assess the diagnostic performances of the new Carestart G6PD quantitative biosensor.A total of 150 samples of venous blood with G6PD deficient, intermediate and normal phenotypes were collected among healthy volunteers living along the north-western Thailand-Myanmar border. Samples were analyzed by complete blood count, by gold standard spectrophotometric assay using Trinity kits and by the latest model of Carestart G6PD biosensor which analyzes both G6PD and hemoglobin.Bland-Altman comparison of the CareStart normalized G6PD values to that of the gold standard assay showed a strong bias in values resulting in poor area under-the-curve values for both 30% and 80% thresholds. Performing a receiver operator curve identified threshold values for the CareStart product equivalent to the 30% and 80% gold standard values with good sensitivity and specificity values, 100% and 92% (for 30% G6PD activity and 92% and 94% (for 80% activity respectively.The Carestart G6PD biosensor represents a significant improvement for quantitative diagnosis of G6PD deficiency over previous versions. Further

Posttranslational regulation of glucose-6-phosphate dehydrogenase activity in tongue epithelium

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Biagiotti, E.; Bosch, K. S.; Ninfali, P.; Frederiks, W. M.; van Noorden, C. J.

2000-01-01

Expression of glucose-6-phosphate dehydrogenase (G6PD) activity is high in tongue epithelium, but its exact function is still unknown, it may be related;either to the high proliferation rate of this tissue or to protection against oxidative stress. To elucidate its exact role, we localized

Biochemical Analysis of Two Single Mutants that Give Rise to a Polymorphic G6PD A-Double Mutant

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Edson Jiovany Ramírez-Nava

2017-10-01

Full Text Available Glucose-6-phosphate dehydrogenase (G6PD is a key regulatory enzyme that plays a crucial role in the regulation of cellular energy and redox balance. Mutations in the gene encoding G6PD cause the most common enzymopathy that drives hereditary nonspherocytic hemolytic anemia. To gain insights into the effects of mutations in G6PD enzyme efficiency, we have investigated the biochemical, kinetic, and structural changes of three clinical G6PD variants, the single mutations G6PD A+ (Asn126AspD and G6PD Nefza (Leu323Pro, and the double mutant G6PD A− (Asn126Asp + Leu323Pro. The mutants showed lower residual activity (≤50% of WT G6PD and displayed important kinetic changes. Although all Class III mutants were located in different regions of the three-dimensional structure of the enzyme and were not close to the active site, these mutants had a deleterious effect over catalytic activity and structural stability. The results indicated that the G6PD Nefza mutation was mainly responsible for the functional and structural alterations observed in the double mutant G6PD A−. Moreover, our study suggests that the G6PD Nefza and G6PD A− mutations affect enzyme functions in a similar fashion to those reported for Class I mutations.

Characterization of G6PD genotypes and phenotypes on the northwestern Thailand-Myanmar border.

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Germana Bancone

Full Text Available Mutations in the glucose-6-phosphate dehydrogenase (G6PD gene result in red blood cells with increased susceptibility to oxidative damage. Significant haemolysis can be caused by primaquine and other 8-aminoquinoline antimalarials used for the radical treatment of Plasmodium vivax malaria. The distribution and phenotypes of mutations causing G6PD deficiency in the male population of migrants and refugees in a malaria endemic region on the Thailand-Myanmar border were characterized. Blood samples for G6PD fluorescent spot test (FST, G6PD genotyping, and malaria testing were taken from 504 unrelated males of Karen and Burman ethnicities presenting to the outpatient clinics. The overall frequency of G6PD deficiency by the FST was 13.7%. Among the deficient subjects, almost 90% had the Mahidol variant (487G>A genotype. The remaining subjects had Chinese-4 (392G>T, Viangchan (871G>A, Açores (595A>G, Seattle (844G>C and Mediterranean (563C>T variants. Quantification of G6PD activity was performed using a modification of the standard spectrophotometric assay on a subset of 24 samples with Mahidol, Viangchan, Seattle and Chinese-4 mutations; all samples showed a residual enzymatic activity below 10% of normal and were diagnosed correctly by the FST. Further studies are needed to characterise the haemolytic risk of using 8-aminoquinolines in patients with these genotypes.

Neonatal Hyperbilirubinemia in infants with G6PD c.563C > TVariant

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Moiz Bushra

2012-08-01

Full Text Available Abstract Background There is a strong correlation between glucose-6-phosphate dehydrogenase (G6PD deficiency and neonatal hyperbilirubinemia with a rare but potential threat of devastating acute bilirubin encephalopathy. G6PD deficiency was observed in 4–14% of hospitalized icteric neonates in Pakistan. G6PD c.563C > T is the most frequently reported variant in this population. The present study was aimed at evaluating the time to onset of hyperbilirubinemia and the postnatal bilirubin trajectory in infants having G6PD c.563C > T. Methods This was a case–control study conducted at The Aga Khan University, Pakistan during the year 2008. We studied 216 icteric male neonates who were re-admitted for phototherapy during the study period. No selection was exercised. Medical records showed that 32 were G6PD deficient while 184 were G6PD normal. Each infant was studied for birth weight, gestational age, age at the time of presentation, presence of cephalhematoma, sepsis and neurological signs, peak bilirubin level, age at peak bilirubin level, days of hospitalization, whether phototherapy or exchange blood transfusion was initiated, and the outcome. During hospital stay, each baby was tested for complete blood count, reticulocyte count, ABO and Rh blood type, direct antiglobulin test and quantitative G6PD estimation [by kinetic determination of G6PDH]. G6PDgenotype was analyzed in 32 deficient infants through PCR-RFLP analysis and gene sequencing. Results G6PD variants c.563C > T and c.131 C > G were observed in 21 (65% and three (9% of the 32 G6PD deficient infants, respectively. DNA of eight (25% newborns remained uncharacterized. In contrast to G6PD normal neonates, infants with c.563C > T variant had significantly lower enzyme activity (mean ± 1SD; 0.3 ± 0.2 U/gHb vs. 14.0 ± 4.5 U/gHb, p p = 0.008 which peaked earlier after birth (mean ± 1SD 2.9 ± 1.6 vs. 4.3 ± 2.3 days, p = 0.007. No statistically significant

Methods for the field evaluation of quantitative G6PD diagnostics: a review.

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Ley, Benedikt; Bancone, Germana; von Seidlein, Lorenz; Thriemer, Kamala; Richards, Jack S; Domingo, Gonzalo J; Price, Ric N

2017-09-11

Individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency are at risk of severe haemolysis following the administration of 8-aminoquinoline compounds. Primaquine is the only widely available 8-aminoquinoline for the radical cure of Plasmodium vivax. Tafenoquine is under development with the potential to simplify treatment regimens, but point-of-care (PoC) tests will be needed to provide quantitative measurement of G6PD activity prior to its administration. There is currently a lack of appropriate G6PD PoC tests, but a number of new tests are in development and are likely to enter the market in the coming years. As these are implemented, they will need to be validated in field studies. This article outlines the technical details for the field evaluation of novel quantitative G6PD diagnostics such as sample handling, reference testing and statistical analysis. Field evaluation is based on the comparison of paired samples, including one sample tested by the new assay at point of care and one sample tested by the gold-standard reference method, UV spectrophotometry in an established laboratory. Samples can be collected as capillary or venous blood; the existing literature suggests that potential differences in capillary or venous blood are unlikely to affect results substantially. The collection and storage of samples is critical to ensure preservation of enzyme activity, it is recommended that samples are stored at 4 °C and testing occurs within 4 days of collection. Test results can be visually presented as scatter plot, Bland-Altman plot, and a histogram of the G6PD activity distribution of the study population. Calculating the adjusted male median allows categorizing results according to G6PD activity to calculate standard performance indicators and to perform receiver operating characteristic (ROC) analysis.

Kinetic Behaviour of Glucose 6-Phosphate Dehydrogenase and 6-Phosphogluconate Dehydrogenase in Different Tissues of Rainbow Trout (Oncorhynchus mykiss Exposed to Non-Lethal Concentrations of Cadmium

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Olcay Hisar

2009-01-01

Full Text Available The effects of cadmium (Cd on the enzymatic activities of glucose 6-phosphate dehydrogenase (G6PD and 6-phosphogluconate dehydrogenase (6PGD were investigated in the gill, liver and kidney tissues of rainbow trout (Oncorhynchus mykiss. Three test groups of fish were subjected to increasing concentrations (1, 3 and 5 mg/l of cadmium (Cd in vivo, respectively. The G6PD and 6PGD activities in the gill, liver, and kidney tissues of each group of fish were measured on days 1, 3, 5 and 7. G6PD and 6PGD enzyme activities, measured in gill, liver and kidney homogenates, were stimulated by various concentrations (1, 3, and 5 mg/l of cadmium. Although the dose-response pattern of G6PD enzyme activities in liver and kidney tissue was very similar, that in gill was different from both other tissues. The enzyme activity of G6PD enzyme was significantly stimulated after three days (Day 3 in liver and kidney tissues at a dose of 1 mg/l Cd (p p p p p p < 0.05 in liver and kidney tissues at the doses of 3 and 1 mg/l Cd. The stimulation effect of cadmium on the three tissues studied was also calculated; for both of the enzymes (G6PD and 6PGD, the enzyme activity levels were stimulated by approximately 60% and 38% in gills, 68% and 44% in liver, and 67% and 41% in kidneys, respectively, over the base-line enzyme activity of the control groups during the sevenday experimental period. These findings indicate that tissue G6PD and 6PGD enzymes function to protect against cadmium toxicity.

Effect of thoracic x-irradiation on glucose-6-phosphate dehydrogenase activity of the pectoral muscle of guinea pig

International Nuclear Information System (INIS)

Bhatavdekar, J.M.; Shah, V.C.

1981-01-01

The histochemical distribution of glucose-6-phosphate dehydrogenase (G6PD) was observed in the major pectoral muscle of a guinea pig that had received 240 R thoracic X-irradiation. The irradiation effects were studied at 24, 48 and 72 hrs after X-irradiation. Type I fibres of the pectoral muscle were deeply stained showing high activity whereas type II fibres demonstrated minimum enzyme activity. The intermediate fibres had medium levels of G6PD activity. Type II fibres showed more staining at 24 and 48 hrs as compared with control muscle. However, at 72 hrs all three fibre types showed a marked inhibition of G6PD activity. The significance of these changes suggests that muscle G6PD metabolism generally altered after irradiation, but the specific nature of these changes and their causes still remain unclear. (author)

Autoinflammatory Reaction in Dogs Treated for Cancer via G6PD Inhibition

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Jonathan W. Nyce

2017-01-01

Full Text Available Glucose-6-phosphate dehydrogenase (G6PD is an oncoprotein that is overexpressed in cancer cells to provide the NADPH required for their increased anabolism. NADPH, sourced from G6PD fuels nucleotide biosynthesis, maintains redox potential of thioredoxin and glutathione and drives the mevalonate pathway that powers many of the basic mechanisms by which cancer cells escape host control. G6PD is thus a target for cancer treatment being addressed by many groups around the world. We have discovered that systemic inhibition of G6PD by high dose dehydroepiandrosterone (DHEA causes a severe autoinflammatory response in dogs, which does not occur in mice or rats. Since dogs more closely model the human adrenal androgen system than do common laboratory animals, this finding is relevant to the design of G6PD-inhibiting drugs for humans. The autoinflammatory reaction observed closely resembles mevalonate kinase deficiency (MKD, a rare autosomal recessive disease in humans characterized by recurrent febrile attacks, arthralgia, skin rash, and aphthous ulcers of mucocutaneous tissues. In a manner comparable to animal models of MKD, the reconstitution of protein geranylgeranylation blocked the autoinflammatory reaction caused by systemic G6PD inhibition. This autoinflammatory response to systemic G6PD inhibition represents an unexpected result that must be taken into consideration when targeting this oncoprotein.

Glucose-6-phosphate dehydrogenase deficiency in Singapore.

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Quak, S H; Saha, N; Tay, J S

1996-01-01

Glucose-6-phosphate dehydrogenase (G6PD) in man is an X-linked enzyme. The deficiency of this enzyme is one of the most common inherited metabolic disorders in man. In Singapore, three clinical syndromes associated with G6PD deficiency had been described: severe haemolysis in neonates with kernicterus, haemoglobinuria and "viral hepatitis"-like syndrome. The human G6PD monomer consists of 515 amino acids. Only the tetrameric or dimeric forms composed of a single type subunit are catylitically active. The complete amino acid sequence of G6PD had been elucidated in man and various other animals. The region of high homology among the enzymes of various animals is presumably functionally active. Among the Chinese in Singapore, three common molecular variants had been identified: Canton (nt 1376 G --> T), Kaiping (nt 1388 G --> A) and Mediterranean (nt 563 C --> T) in frequencies of 24%, 21% and 10% respectively. In addition, two common mutants (Gaozhou, nt 95 A --> G and Chinese 5, nt 1024 C --> T) have been detected in Singapore Chinese in low frequencies. In Malays, 6 different deficient variants are known in Singapore (3 new, 1 Mahidol, 1 Indonesian and 1 Mediterranean).

X-Linked G6PD Deficiency Protects Hemizygous Males but Not Heterozygous Females against Severe Malaria

OpenAIRE

Guindo, Aldiouma; Fairhurst, Rick M; Doumbo, Ogobara K; Wellems, Thomas E; Diallo, Dapa A

2007-01-01

Editors' Summary Background. “Favism” is a condition that results from a deficiency in an enzyme called glucose-6-phosphate dehydrogenase (G6PD), and this disorder is thought to be the commonest enzyme-deficiency disease worldwide. The disease is named favism after the Italian word for broad beans (fava), which cause a classic reaction when eaten by people with G6PD deficiency. The G6PD enzyme is particularly important in red blood cells, where it protects against damage that can be caused by...

G6PD Deficiency in an HIV Clinic Setting in the Dominican Republic

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Xu, Julia Z.; Francis, Richard O.; Lerebours Nadal, Leonel E.; Shirazi, Maryam; Jobanputra, Vaidehi; Hod, Eldad A.; Jhang, Jeffrey S.; Stotler, Brie A.; Spitalnik, Steven L.; Nicholas, Stephen W.

2015-01-01

Because human immunodeficiency virus (HIV)-infected patients receive prophylaxis with oxidative drugs, those with glucose-6-phosphate dehydrogenase (G6PD) deficiency may experience hemolysis. However, G6PD deficiency has not been studied in the Dominican Republic, where many individuals have African ancestry. Our objective was to determine the prevalence of G6PD deficiency in Dominican HIV-infected patients and to attempt to develop a cost-effective algorithm for identifying such individuals. To this end, histories, chart reviews, and G6PD testing were performed for 238 consecutive HIV-infected adult clinic patients. The overall prevalence of G6PD deficiency (8.8%) was similar in males (9.3%) and females (8.5%), and higher in Haitians (18%) than Dominicans (6.4%; P = 0.01). By logistic regression, three clinical variables predicted G6PD status: maternal country of birth (P = 0.01) and a history of hemolysis (P = 0.01) or severe anemia (P = 0.03). Using these criteria, an algorithm was developed, in which a patient subset was identified that would benefit most from G6PD screening, yielding a sensitivity of 94.7% and a specificity of 97.2%, increasing the pretest probability (8.8–15.1%), and halving the number of patients needing testing. This algorithm may provide a cost-effective strategy for improving care in resource-limited settings. PMID:26240158

Prevalence of glucose-6-phosphate dehydrogenase deficiency in ...

African Journals Online (AJOL)

Background: Glucose-6-phosphate dehydrogenase (G6PD) is a house keeping enzyme which catalyzes the first step in the hexose monophosphate pathway of glucose metabolism. G6PD deficiency is the commonest hemolytic X-linked genetic disease, which affects approximately 400 million people worldwide.

Glucose 6 phosphate dehydrogenase deficiency in adults

International Nuclear Information System (INIS)

Khan, M.

2004-01-01

Objective: To determine the frequency of glucose-6-phosphate dehydrogenase (G6PD) deficiency in adults presented with anemia. Subjects and Methods: Eighteen months admission data was reviewed for G6PD deficiency as a cause of anemia. Anemia was defined by world health organization (WHO) criteria as haemoglobin less than 11.3 gm%. G6PD activity was measured by Sigma dye decolorisation method. All patients were screened for complications of hemolysis and its possible cause. Patients with more than 13 years of age were included in the study. Results: Out of 3600 patients admitted, 1440 were found anaemic and 49 as G6PD deficient. So the frequency of G6PD deficiency in anaemic patients was 3.4% and the overall frequency is 1.36%. G6PD deficiency among males and females was three and six percent respectively. Antimalarials and antibiotics containing sulphonamide group were the most common precipitating factors for hemolysis. Anemia and jaundice were the most common presentations while malaria was the most common associated disease. Acute renal failure was the most severe complication occurring in five patients with two deaths. Conclusion: G6PD deficiency is a fairly common cause of anemia with medicine as common precipitating factor for hemolysis. Such complications can be avoided with early recognition of the disease and avoiding indiscriminate use of medicine. (author)

Genetics Home Reference: glucose-6-phosphate dehydrogenase deficiency

Science.gov (United States)

... deficiency Encyclopedia: Glucose-6-phosphate dehydrogenase test Encyclopedia: Hemolytic anemia Encyclopedia: Newborn jaundice Health Topic: Anemia Health Topic: G6PD Deficiency Health Topic: Newborn Screening Genetic and Rare Diseases Information Center (1 link) Glucose-6-phosphate dehydrogenase ...

Possible association of 3' UTR +357 A>G, IVS11-nt 93 T>C, c.1311 C>T polymorphism with G6PD deficiency.

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Sirdah, Mahmoud M; Shubair, Mohammad E; Al-Kahlout, Mustafa S; Al-Tayeb, Jamal M; Prchal, Josef T; Reading, N Scott

2017-07-01

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common X-linked inherited enzymopathic disorder affecting more than 500 million people worldwide. It has so far been linked to 217 distinct genetic variants in the exons and exon-intron boundaries of the G6PD gene, giving rise to a wide range of biochemical heterogeneity and clinical manifestations. Reports from different settings suggested the association of intronic and other mutations outside the reading frame of the G6PD gene with reduced enzyme activity and presenting clinical symptoms. The present study aimed to investigate any association of other variations apart of the exonic or exonic intronic boundaries in the development of G6PD deficiency. Sixty-seven unrelated Palestinian children admitted to the pediatric hospital with hemolytic crises due to G6PD deficiency were studied. In our Palestinian cohort of 67 [59 males (M) and 8 females (F)] G6PD-deficient children, previously hospitalized for acute hemolytic anemia due to favism, molecular sequencing of the G6PD gene revealed four cases (3M and 1F) that did not have any of the variants known to cause G6PD deficiency, but the 3' UTR c.*+357A>G (rs1050757) polymorphism in association with IVS 11 (c.1365-13T>C; rs2071429), and c.1311C>T (rs2230037). We now provide an additional evidence form Palestinian G6PD-deficient subjects for a possible role of 3' UTR c.*+357 A>G, c.1365-13T>C, and/or c.1311C>T polymorphism for G6PD deficiency, suggesting that not only a single variation in the exonic or exonic intronic boundaries, but also a haplotype of G6PD should considered as a cause for G6PD deficiency.

Reduced prevalence of Plasmodium falciparum infection and of concomitant anaemia in pregnant women with heterozygous G6PD deficiency

NARCIS (Netherlands)

Mockenhaupt, Frank P.; Mandelkow, Jantina; Till, Holger; Ehrhardt, Stephan; Eggelte, Teunis A.; Bienzle, Ulrich

2003-01-01

Glucose-6-phosphate dehydrogenase (G6PD) deficiency confers protection against malaria in children, yet its role in malaria in pregnancy is unknown. In a cross-sectional study among 529 pregnant Ghanaian women, Plasmodium falciparum infection, anaemia and G6PD genotypes were assessed. Of these,

Glucose 6-phosphate dehydrogenase: isoenzymatic pattern in Oesophagostomum venulosum, Trichuris ovis and T. suis.

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Rodriguez, B; Cutillas, C; German, P; Guevara, D

1991-12-01

In the present communication we have studied the isoenzymatic pattern activity of the glucose 6-phosphate dehydrogenase (G6PD) in Oesophagostomum venulosum, Trichuris ovis and T. suis, parasites of Capra hircus (goat), Ovis aries (sheep) and Sus scrofa domestica (pig) respectively, by polyacrylamide gel electrophoresis. Different phenotypes have been observed in the G6PD isoenzymatic pattern activity in males and females of Oesophagostomum venulosum. Furthermore, G6PD activity has been assayed in Trichuris ovis collected from Ovis aries and Capra hircus. No differences have been observed in the isoenzymatic patterns attending to the different hosts. All the individuals exhibited one single band or two bands; this suggests a monomeric condition for G6PD in T. ovis. In T. suis the enzyme G6PD appeared as a single electrophoretic band in about 85.7% of the individuals.

Glucose 6-phosphate dehydrogenase variants in Japan.

Science.gov (United States)

Miwa, S

1980-01-01

Fifty-four cases of glucose 6-phosphate dehydrogenase (G6PD) deficiency have so far been reported in Japan. Among them, 21 G6PD variants have been characterized. Nineteen out of the 21 variants were characterized in our laboratory and G6PD Heian and "Kyoto" by others. G6PD Tokyo, Tokushima, Ogikubo, Kurume, Fukushima, Yokohama, Yamaguchi, Wakayama, Akita, Heian and "Kyoto" were classified as Class 1, because all these cases showed chronic hemolytic anemia and severe enzyme deficiency. All these variants showed thermal instability. G6PD Mediterranean-like, Ogori, Gifu and Fukuoka were classified as Class 2, whereas G6PD Hofu, B(-) Chinese, Ube, Konan, Kamiube and Kiwa belonged to Class 3. All the 6 Class 3 variants were found as the results of the screening tests. The incidence of the deficiency in Japanese seems to be 0.1-0.5% but that of the cases which may slow drug-induced hemolysis would be much less. G6PD Ube and Konan appear to be relatively common in Japan.

Atividade da 6-fosfogliconato desidrogenase em deficientes de glicose-6-fosfato desidrogenase Activity of 6-phosphogluconate dehydrogenase in glucose-6-phosphate dehydrogenase deficiency

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Daniela B. Nicolielo

2006-06-01

to know better the actuation of these enzymes. The goal of this study was to evaluate the 6PGD enzymatic activity on a population with G6PD deficiency, to verify if there is an elevation of the activity of this enzyme, and try to correlate to a possible increase on the number of reticulocytes or the presence of alterations on red series. The research with 2657 male individuals detected 97 deficient for G6PD, which determined a 3.65% prevalence for the Bauru (SP region, with mean enzymatic activity of 1.74 UI.g Hb-1. min-1 at 37ºC, 14,4% of the normal G6PD activity. Mean 6PGD enzymatic activity was 9.5 UI.g Hb-1. min-1 at 37ºC, and was elevated in 47.4% of the G6PD deficient individuals. The result obtained did not confirm the hypothesis that the elevation of the 6PGD enzymatic activity, in G6PD deficient individuals, was due to the presence of an increase of reticulocytes in blood stream, age or erythrocytometric alterations that could denote anemia. The most plausible theory is that the auto-limited hemolysis, imposed by oxidative processes, preserves young erythrocytes that have an elevated enzymatic activity, as naturally these enzymes lose activity with cellular aging.

Erythrocyte glucose-6-phosphate dehydrogenase from Brazilian opossum Didelphis marsupialis

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Barretto O.C. de O.

2006-01-01

Full Text Available In a comparative study of erythrocyte metabolism of vertebrates, the specific activity of glucose-6-phosphate dehydrogenase (G6PD of the Brazilian opossum Didelphis marsupialis in a hemolysate was shown to be high, 207 ± 38 IU g-1 Hb-1 min-1 at 37ºC, compared to the human erythrocyte activity of 12 ± 2 IU g-1 Hb-1 min-1 at 37ºC. The apparent high specific activity of the mixture led us to investigate the physicochemical properties of the opossum enzyme. We report that reduced glutathione (GSH in the erythrocytes was only 50% higher than in human erythrocytes, a value lower than expected from the high G6PD activity since GSH is maintained in a reduced state by G6PD activity. The molecular mass, determined by G-200 Sephadex column chromatography at pH 8.0, was 265 kDa, which is essentially the same as that of human G6PD (260 kDa. The Michaelis-Menten constants (Km: 55 µM for glucose-6-phosphate and nicotinamide adenine dinucleotide phosphate (Km: 3.3 µM were similar to those of the human enzyme (Km: 50-70 and Km: 2.9-4.4, respectively. A 450-fold purification of the opossum enzyme was achieved and the specific activity of the purified enzyme, 90 IU/mg protein, was actually lower than the 150 IU/mg protein observed for human G6PD. We conclude that G6PD after purification from the hemolysate of D. marsupialis does not have a high specific activity. Thus, it is quite probable that the red cell hyperactivity reported may be explained by increased synthesis of G6PD molecules per unit of hemoglobin or to reduced inactivation in the RBC hemolysate.

Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines for rasburicase therapy in the context of G6PD deficiency genotype.

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Relling, M V; McDonagh, E M; Chang, T; Caudle, K E; McLeod, H L; Haidar, C E; Klein, T; Luzzatto, L

2014-08-01

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is associated with development of acute hemolytic anemia (AHA) induced by a number of drugs. We provide guidance as to which G6PD genotypes are associated with G6PD deficiency in males and females. Rasburicase is contraindicated in G6PD-deficient patients due to the risk of AHA and possibly methemoglobinemia. Unless preemptive genotyping has established a positive diagnosis of G6PD deficiency, quantitative enzyme assay remains the mainstay of screening prior to rasburicase use. The purpose of this article is to help interpret the results of clinical G6PD genotype tests so that they can guide the use of rasburicase. Detailed guidelines on other aspects of the use of rasburicase, including analyses of cost-effectiveness, are beyond the scope of this document. Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines are published and updated periodically on https://www.pharmgkb.org/page/cpic to reflect new developments in the field.

Evaluation of Glucose-6-Phosphate Dehydrogenase stability in stored blood samples.

Science.gov (United States)

Jalil, Norunaluwar; Azma, Raja Zahratul; Mohamed, Emida; Ithnin, Azlin; Alauddin, Hafiza; Baya, Siti Noor; Othman, Ainoon

2016-01-01

Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency is the commonest cause of neonatal jaundice in Malaysia. Recently, OSMMR2000-D G6PD Assay Kit has been introduced to quantitate the level of G6PD activity in newborns delivered in Universiti Kebangsaan Malaysia Medical Centre (UKMMC). As duration of sample storage prior to analysis is one of the matters of concern, this study was conducted to identify the stability of G6PD enzyme during storage. A total of 188 cord blood samples from normal term newborns delivered at UKMMC were selected for this study. The cord bloods samples were collected in ethylene-diamine-tetra-acetic acid (EDTA) tubes and refrigerated at 2-8 °C. In addition, 32 out of 188 cord blood samples were spotted on chromatography paper, air-dried and stored at room temperature. G6PD enzyme activities were measured daily for 7 days using the OSMMR2000-D G6PD Assay Kit on both the EDTA blood and dried blood samples. The mean value for G6PD activity was compared between days of analysis using Student Paired T-Test. In this study, 172 out of 188 cord blood samples showed normal enzyme levels while 16 had levels corresponding to severe enzyme deficiency. The daily mean G6PD activity for EDTA blood samples of newborns with normal G6PD activity showed a significant drop on the fourth day of storage (p samples with severely deficient G6PD activity, significant drop was seen on third day of storage (p = 0.002). Analysis of dried cord blood showed a significant reduction in enzyme activity as early as the second day of storage (p = 0.001). It was also noted that mean G6PD activity for spotted blood samples were lower compared to those in EDTA tubes for all days (p = 0.001). Thus, EDTA blood samples stored at 2-8 °C appeared to have better stability in terms of their G6PD enzyme level as compared to dried blood samples on filter paper, giving a storage time of up to 3 days.

Severe acute haemolytic anaemia associated with severe methaemoglobinaemia in a G6PD-deficient man.

Science.gov (United States)

Rehman, Abdul; Shehadeh, Mohanad; Khirfan, Diala; Jones, Akhnuwhkh

2018-03-28

Methaemoglobin is a form of haemoglobin in which the ferrous (Fe 2+ ) ion contained in the iron-porphyrin complex of haem is oxidised to its ferric (Fe 3+ ) state. Methaemoglobinaemia, the presence of methaemoglobin in the blood, is most commonly treated with methylene blue. However, methylene blue cannot be used in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency as it is ineffective in such patients and it can worsen G6PD deficiency haemolysis. We report the case of a 30-year-old man who presented with clinical features of G6PD deficiency-associated haemolysis and was found to have severe methaemoglobinaemia (35%). He was administered blood transfusions and intravenous ascorbic acid. His methaemoglobinaemia resolved within 24 hours. This case demonstrates the successful management of a patient with severe methaemoglobinaemia in the setting of G6PD deficiency haemolysis. Emergency physicians should be aware of the possible co-occurrence of severe methaemoglobinaemia in a patient with G6PD deficiency haemolysis. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Glucose-6-phosphate dehydrogenase and glutathione reductase activity in methemoglobin reduction by methylene blue and cyst amine: study on glucose-6-phosphate dehydrogenase-deficient individuals, on normal subjects and on riboflavin-treated subjects

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Benedito Barraviera

1988-10-01

Full Text Available The authors have standardized methods for evaluation of the activity of the glucose-6-phosphate dehydrogenase and of glutathione reductase. The general principle of the first method was based on methemoglobin formation by sodium nitrite followed by stimulation of the glucose-6-phosphate dehydrogenase with methylene blue. Forty six adults (23 males and 23 females were studied. Subjects were not G6PD deficient and were aged 20 to 30 years. The results showed that methemoglobin reduction by methylene blue was 154.40 and 139.90 mg/min (p<0.05 for males and females, respectively, in whole blood, and 221.10 and 207.85 mg/min (n.s., respectively, in washed red cells. These data showed that using washed red cells and 0.7g% sodium nitrite concentration produced no differences between sexes and also shortened reading time for the residual amount of methemoglobin to 90 minutes. Glutathione reductase activity was evaluated on the basis of the fact that cystamine (a thiol agent binds to the SH groups of hemoglobin, forming complexes. These complexes are reversed by the action of glutathione reductase, with methemoglobin reduction occurring simultaneously with this reaction. Thirty two adults (16 males and 16 females were studied. Subjects were not G6PD deficient and were aged 20 to 30 years. Methemoglobin reduction by cystamine was 81.27 and 91.13 mg/min (p<0.01 for males and females, respectively. These data showed that using washed red cells and 0.1 M cystamine concentration permits a reading of the residual amount of methemoglobin at 180 minutes of incubation. Glutathione reductase activity was evaluated by methemoglobin reduction by cystamine in 14 females before and after treatment with 10 mg riboflavin per day for 8 days. The results were 73.69 and 94.26 jug/min (p<0.01 before and after treatment, showing that riboflavin treatment increase glutathione reductase activity even in normal individuals. Three Black G6PD-deficient individuals (2 males and 1

Biochemical and cytochemical evaluation of heterozygote individuals with glucose-6-phosphate dehydrogenase deficiency

NARCIS (Netherlands)

Gurbuz, Nilgun; Aksu, Tevfik Aslan; van Noorden, Cornelis J. F.

2005-01-01

The aim of this study was to diagnose heterozygous glucose-6-phosphate dehydrogenase (G6PD) deficient females by an inexpensive cytochemical G6PD staining method that is easy to perform, allowing diagnosis of G6PD deficiency without cumbersome genetic analysis. Three subject groups were included in

L-Cysteine in vitro can restore cellular glutathione and inhibits the expression of cell adhesion molecules in G6PD-deficient monocytes.

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Parsanathan, Rajesh; Jain, Sushil K

2018-04-06

L-Cysteine is a precursor of glutathione (GSH), a potent physiological antioxidant. Excess glucose-6-phosphate dehydrogenase (G6PD) deficiency in African Americans and low levels of L-cysteine diet in Hispanics can contributes to GSH deficiency and oxidative stress. Oxidative stress and monocyte adhesion was considered to be an initial event in the progression of vascular dysfunction and atherosclerosis. However, no previous study has investigated the contribution of GSH/G6PD deficiency to the expression of monocyte adhesion molecules. Using human U937 monocytes, this study examined the effect of GSH/G6PD deficiency and L-cysteine supplementation on monocyte adhesion molecules. G6PD/GSH deficiency induced by either siRNA or inhibitors (6AN/BSO, respectively) significantly (p adhesion molecules (ICAM-1, VCAM-1, SELL, ITGB1 and 2); NADPH oxidase (NOX), reactive oxygen species (ROS) and MCP-1 were upregulated, and decreases in levels of GSH, and nitric oxide were observed. The expression of ICAM-1 and VCAM-1 mRNA levels increased in high glucose, MCP-1 or TNF-α-treated G6PD-deficient compared to G6PD-normal cells. L-Cysteine treatment significantly (p adhesion molecules. Thus, GSH/G6PD deficiency increases susceptibility to monocyte adhesion processes, whereas L-cysteine supplementation can restore cellular GSH/G6PD and attenuates NOX activity and expression of cell adhesion molecules.

Demonstration of glucose-6-phosphate dehydrogenase in rat Kupffer cells by a newly-developed ultrastructural enzyme-cytochemistry

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S Matsubara

2009-06-01

Full Text Available Although various tissue macrophages possess high glucose- 6-phosphate dehydrogenase (G6PD activity, which is reported to be closely associated with their phagocytotic/bactericidal function, the fine subcellular localization of this enzyme in liver resident macrophages (Kupffer cells has not been determined.We have investigated the subcellular localization of G6PD in Kupffer cells in rat liver, using a newly developed enzyme-cytochemical (copper-ferrocyanide method. Electron-dense precipitates indicating G6PD activity were clearly visible in the cytoplasm and on the cytosolic side of the endoplasmic reticulum of Kupffer cells. Cytochemical controls ensured specific detection of the enzymatic activity. Rat Kupffer cells abundantly possessed enzyme-cytochemically detectable G6PD activity. Kupffer cell G6PD may play a role in liver defense by delivering NADPH to NADPH-dependent enzymes. G6PD enzyme-cytochemistry may be a useful tool for the study of Kupffer cell functions.

BAG3 elevation inhibits cell proliferation via direct interaction with G6PD in hepatocellular carcinomas.

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Kong, De-Hui; Li, Si; Du, Zhen-Xian; Liu, Chuan; Liu, Bao-Qin; Li, Chao; Zong, Zhi-Hong; Wang, Hua-Qin

2016-01-05

Bcl-2 associated athanogene 3 (BAG3) contains multiple protein-binding motifs to mediate potential interactions with chaperons and/or other proteins, which is possibly ascribed to the multifaceted functions assigned to BAG3. The current study demonstrated that BAG3 directly interacted with glucose 6 phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the pentose phosphate pathway (PPP). BAG3 suppressed the PPP flux, de novo DNA synthesis and cell growth in hepatocellular carcinomas (HCCs). The growth defect of HCCs with forced BAG3 expression can be rescued by enforced G6PD expression. However, BAG3 elevation did not cause a reduction in cellular NADPH concentrations, another main product of G6PD. In addition, supplement of nucleosides alone was sufficient to recover the growth defect mediated by BAG3 elevation. Collectively, the current study established a tumor suppressor-like function of BAG3 via direct interaction with G6PD in HCCs at the cellular level.

Prevalence of G6PD deficiency in selected populations from two previously high malaria endemic areas of Sri Lanka.

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Sharmini Gunawardena

Full Text Available Glucose-6-Phosphate Dehydrogenase (G6PD enzyme deficiency is known to offer protection against malaria and an increased selection of mutant genes in malaria endemic regions is expected. However, anti-malarial drugs such as primaquine can cause haemolytic anaemia in persons with G6PD deficiency. We studied the extent of G6PD deficiency in selected persons attending Teaching Hospitals of Anuradhapura and Kurunegala, two previously high malaria endemic districts in Sri Lanka. A total of 2059 filter-paper blood spots collected between November 2013 and June 2014 were analysed for phenotypic G6PD deficiency using the modified WST-8/1-methoxy PMS method. Each assay was conducted with a set of controls and the colour development assessed visually as well as with a microplate reader at OD450-630nm. Overall, 142/1018 (13.95% and 83/1041 (7.97% were G6PD deficient in Anuradhapura and Kurunegala districts respectively. The G6PD prevalence was significantly greater in Anuradhapura when compared to Kurunegala (P0.05. Severe deficiency (<10% normal was seen among 28/1018 (2.75% in Anuradhapura (7 males; 21 females and 17/1041 (1.63% in Kurunegala (7 males; 10 females. Enzyme activity between 10-30% was observed among 114/1018 (11.20%; 28 males; 86 females in Anuradhapura while it was 66/1041 (6.34%; 18 males; 48 females in Kurunegala. Screening and educational programmes for G6PD deficiency are warranted in these high risk areas irrespective of gender for the prevention of disease states related to this condition.

Kawasaki disease with G6PD deficiency--report of one case and literature review.

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Chen, Chia-Hao; Lin, Li-Yan; Yang, Kuender D; Hsieh, Kai-Sheng; Kuo, Ho-Chang

2014-06-01

Kawasaki disease (KD) is a systemic vasculitis primarily affecting children who are younger than 5 years. The most serious complications are coronary artery aneurysms and sequelae of vasculitis with the subsequent development of coronary artery aneurysm. According to the literature, intravenous immunoglobulin (IVIG) plus high-dose aspirin (acetylsalicylic acid) were standard treatment for KD, whereas low-dose aspirin (3-5 mg/kg/day) was used for thrombocytosis in KD via antiplatelet effect. However, aspirin has been reported to have hemolytic potential in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency. We report a child with G6PD-deficiency who has KD, and review the literature. Copyright © 2012. Published by Elsevier B.V.

THE ASSOCIATION BETWEEN G6PD DEFICIENCY AND TOTAL SERUM BILIRUBIN LEVEL IN ICTERIC NEONATES

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S. Behjati-Ardakani

2007-07-01

Full Text Available "nGlucose-6-phosphate dehydrogenase (G6PD deficiency is the most important disease of the hexose monophosphate pathway. Deficiency of this enzym can lead to hemolysis of red blood cells. Our aim was to study the prevalence of G6PD deficiency in relation to neonatal jaundice. We studied 456 clinically icteric neonates Laboratory investigations included determination of direct and indirect serum bilirubin concentrations, blood group typing, direct coomb's test, hemoglobin, blood smear, reticulocyte count and G6PD level. We divided these neonates to 3 groups based on total serum bilirubin level (TSB: TSB< 20 mg%, TSB=20-25 mg%, and TSB>25 mg%. In only 35 (7.6% of cases G6PD deficiency was diagnosed. All of these babies were male. From 456 icteric neonates, 213 cases belong to group 1 (TSB<20 mg%, 158 cases belong to group 2 (TSB=20-25 mg% and 85 cases belong to group 3 (TSB>25 mg%. 16 neonates from 213 neonates of group 1, 6 neonates from 158 neonates of group 2 and 13 neonates from 85 neonates of group 3 had G6PD deficiency. There was statistically significant difference of prevalence of G6PD deficiency between group 2 and 3 ( 15.3% vs 3.8%( P = 0.001. Between groups 1 vs 2 and 1 vs 3 no statistically significant difference was found. Early detection of this enzymopathy regardless of sex and close surveillance of the affected newborns may be important in reducing the risk of severe hyperbilirubinemia. This emphasizes the necessity of neonatal screening on cord blood samples for G6PD deficiency.

Variant G6PD levels promote tumor cell proliferation or apoptosis via the STAT3/5 pathway in the human melanoma xenograft mouse model

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Hu, Tao; Zhang, Chunhua; Tang, Qiongling; Su, Yanan; Li, Bo; Chen, Long; Zhang, Zheng; Cai, Tianchi; Zhu, Yuechun

2013-01-01

Glucose-6-phosphate dehydrogenase (G6PD), elevated in tumor cells, catalyzes the first reaction in the pentose-phosphate pathway. The regulation mechanism of G6PD and pathological change in human melanoma growth remains unknown. HEM (human epidermal melanocyte) cells and human melanoma cells with the wild-type G6PD gene (A375-WT), G6PD deficiency (A375-G6PD∆), G6PD cDNA overexpression (A375-G6PD∆-G6PD-WT), and mutant G6PD cDNA (A375-G6PD∆-G6PD-G487A) were subcutaneously injected into 5 groups of nude mice. Expressions of G6PD, STAT3, STAT5, cell cycle-related proteins, and apoptotic proteins as well as mechanistic exploration of STAT3/STAT5 were determined by quantitative real-time PCR (qRT-PCR), immunohistochemistry and western blot. Delayed formation and slowed growth were apparent in A375-G6PD∆ cells, compared to A375-WT cells. Significantly decreased G6PD expression and activity were observed in tumor tissues induced by A375-G6PD∆, along with down-regulated cell cycle proteins cyclin D1, cyclin E, p53, and S100A4. Apoptosis-inhibited factors Bcl-2 and Bcl-xl were up-regulated; however, apoptosis factor Fas was down-regulated, compared to A375-WT cells. Moderate protein expressions were observed in A375-G6PD∆-G6PD-WT and A375-G6PD∆-G6PD-G487A cells. G6PD may regulate apoptosis and expression of cell cycle-related proteins through phosphorylation of transcription factors STAT3 and STAT5, thus mediating formation and growth of human melanoma cells. Further study will, however, be required to determine potential clinical applications

The effects of chemical and radioactive properties of Tl-201 on human erythrocyte glucose 6-phosphate dehydrogenase activity

International Nuclear Information System (INIS)

Sahin, Ali; Senturk, Murat; Ciftci, Mehmet; Varoglu, Erhan; Kufrevioglu, Omer Irfan

2010-01-01

Aim: The inhibitory effects of thallium-201 ( 201 Tl) solution on human erythrocyte glucose 6-phosphate dehydrogenase (G6PD) activity were investigated. Methods: For this purpose, erythrocyte G6PD was initially purified 835-fold at a yield of 41.7% using 2',5'-Adenosine diphosphate sepharose 4B affinity gel chromatography. The purification was monitored by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, which showed a single band for the final enzyme preparation. The in vitro and in vivo effects of the 201 Tl solution including Tl + , Fe +3 and Cu +2 metals and the in vitro effects of the radiation effect of the 201 Tl solution and non-radioactive Tl + , Fe +3 and Cu +2 metals on human erythrocyte G6PD enzyme were studied. Enzyme activity was determined with the Beutler method at 340 nm using a spectrophotometer. All purification procedures were carried out at +4 deg. C. Results: 201 Tl solution and radiation exposure had inhibitory effects on the enzyme activity. IC 50 value of 201 Tl solution was 36.86 μl ([Tl + ]: 0.0036 μM, [Cu +2 ]: 0.0116 μM, [Fe +3 ]: 0.0132 μM), of human erythrocytes G6PD. Seven human patients were also used for in vivo studies of 201 Tl solution. Furthermore, non-radioactive Tl + , Fe +3 and Cu +2 were found not to have influenced the enzyme in vitro. Conclusion: Human erythrocyte G6PD activity was inhibited by exposure for up to 10 minutes to 0.057 mCi/kg 201 Tl solution. It was detected in in vitro and in vivo studies that the human erythrocyte G6PD enzyme is inhibited due to the radiation effect of 201 Tl solution.

Prevalence and molecular characterization of G6PD deficiency in two Plasmodium vivax endemic areas in Venezuela: predominance of the African A-(202A/376G) variant.

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Vizzi, Esmeralda; Bastidas, Gilberto; Hidalgo, Mariana; Colman, Laura; Pérez, Hilda A

2016-01-11

Glucose-6-phosphate dehydrogenase (G6PD) deficiency causes acute haemolytic anaemia triggered by oxidative drugs such as primaquine (PQ), used for Plasmodium vivax malaria radical cure. However, in many endemic areas of vivax malaria, patients are treated with PQ without any evaluation of their G6PD status. G6PD deficiency and its genetic heterogeneity were evaluated in northeastern and southeastern areas from Venezuela, Cajigal (Sucre state) and Sifontes (Bolívar state) municipalities, respectively. Blood samples from 664 randomly recruited unrelated individuals were screened for G6PD activity by a quantitative method. Mutation analysis for exons 4-8 of G6PD gen was performed on DNA isolated from G6PD-deficient (G6PDd) subjects through PCR-RFLP and direct DNA sequencing. Quantitative biochemical characterization revealed that overall 24 (3.6%) subjects were G6PDd (average G6PD enzyme activity 4.5 ± 1.2 U/g Hb, moderately deficient, class III), while DNA analysis showed one or two mutated alleles in 19 of them (79.2%). The G6PD A-(202A/376G) variant was the only detected in 17 (70.8%) individuals, 13 of them hemizygous males and four heterozygous females. Two males carried only the 376A → G mutation. No other mutation was found in the analysed exons. The G6PDd prevalence was as low as that one shown by nearby countries. This study contributes to the knowledge of the genetic background of Venezuelan population, especially of those living in malaria-endemic areas. Despite the high degree of genetic mixing described for Venezuelan population, a net predominance of the mild African G6PD A-(202A/376G) variant was observed among G6PDd subjects, suggesting a significant flow of G6PD genes from Africa to Americas, almost certainly introduced through African and/or Spanish immigrants during and after the colonization. The data suggest that 1:27 individuals of the studied population could be G6PDd and therefore at risk of haemolysis under precipitating factors

Glucose-6-Phosphate Dehydrogenase: Update and Analysis of New Mutations around the World

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Gómez-Manzo, Saúl; Marcial-Quino, Jaime; Vanoye-Carlo, America; Serrano-Posada, Hugo; Ortega-Cuellar, Daniel; González-Valdez, Abigail; Castillo-Rodríguez, Rosa Angélica; Hernández-Ochoa, Beatriz; Sierra-Palacios, Edgar; Rodríguez-Bustamante, Eduardo; Arreguin-Espinosa, Roberto

2016-01-01

Glucose-6-phosphate dehydrogenase (G6PD) is a key regulatory enzyme in the pentose phosphate pathway which produces nicotinamide adenine dinucleotide phosphate (NADPH) to maintain an adequate reducing environment in the cells and is especially important in red blood cells (RBC). Given its central role in the regulation of redox state, it is understandable that mutations in the gene encoding G6PD can cause deficiency of the protein activity leading to clinical manifestations such as neonatal jaundice and acute hemolytic anemia. Recently, an extensive review has been published about variants in the g6pd gene; recognizing 186 mutations. In this work, we review the state of the art in G6PD deficiency, describing 217 mutations in the g6pd gene; we also compile information about 31 new mutations, 16 that were not recognized and 15 more that have recently been reported. In order to get a better picture of the effects of new described mutations in g6pd gene, we locate the point mutations in the solved three-dimensional structure of the human G6PD protein. We found that class I mutations have the most deleterious effects on the structure and stability of the protein. PMID:27941691

Neonatal nucleated red blood cells in G6PD deficiency.

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Yeruchimovich, Mark; Shapira, Boris; Mimouni, Francis B; Dollberg, Shaul

2002-05-01

The objective of this study is to study the absolute number of nucleated red blood cells (RBC) at birth, an index of active fetal erythropoiesis, in infants with G6PD deficiency and in controls. We tested the hypothesis that hematocrit and hemoglobin would be lower, and absolute nucleated RBC counts higher, in the G6PD deficient and that these changes would be more prominent in infants exposed passively to fava bean through maternal diet. Thirty-two term infants with G6PD deficiency were compared with 30 term controls. Complete blood counts with manual differential counts were obtained within 12 hours of life. Absolute nucleated RBC and corrected leukocyte counts were computed from the Coulter results and the differential count. G6PD deficient patients did not differ from controls in terms of gestational age, birth weight, or Apgar scores or in any of the hematologic parameters studied, whether or not the mother reported fava beans consumption in the days prior to delivery. Although intrauterine hemolysis is possible in G6PD deficient fetuses exposed passively to fava beans, our study supports that such events must be very rare.

Glucose-6-phosphate dehydrogenase in rat lung alveolar epithelial cells. An ultrastructural enzyme-cytochemical study

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S Matsubara

2010-01-01

Full Text Available Glucose-6-phosphate dehydrogenase (G6PD is the key enzyme of the pentose phosphate pathway in carbohydrate metabolism, and it plays an important role in cell proliferation and antioxidant regulation within cells in various organs. Although marked cell proliferation and oxidant/antioxidant metabolism occur in lung alveolar epithelial cells, definite data has been lacking as to whether cytochemically detectable G6PD is present in alveolar epithelial cells. The distribution pattern of G6PD within these cells, if it is present, is also unknown. The purpose of the present study was to investigate the subcellular localization of G6PD in alveolar cells in the rat lung using a newly- developed enzyme-cytochemistry (copper-ferrocyanide method. Type I cells and stromal endothelia and fibroblasts showed no activities. Electron-dense precipitates indicating G6PD activity were clearly visible in the cytoplasm and on the cytosolic side of the endoplasmic reticulum of type II alveolar epithelial cells. The cytochemical controls ensured specific detection of enzyme activity. This enzyme may play a role in airway defense by delivering substances for cell proliferation and antioxidant forces, thus maintaining the airway architecture.

Functional and Biochemical Characterization of Three Recombinant Human Glucose-6-Phosphate Dehydrogenase Mutants: Zacatecas, Vanua-Lava and Viangchan

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Gómez-Manzo, Saúl; Marcial-Quino, Jaime; Vanoye-Carlo, America; Serrano-Posada, Hugo; González-Valdez, Abigail; Martínez-Rosas, Víctor; Hernández-Ochoa, Beatriz; Sierra-Palacios, Edgar; Castillo-Rodríguez, Rosa Angélica; Cuevas-Cruz, Miguel; Rodríguez-Bustamante, Eduardo; Arreguin-Espinosa, Roberto

2016-01-01

Glucose-6-phosphate dehydrogenase (G6PD) deficiency in humans causes severe disease, varying from mostly asymptomatic individuals to patients showing neonatal jaundice, acute hemolysis episodes or chronic nonspherocytic hemolytic anemia. In order to understand the effect of the mutations in G6PD gene function and its relation with G6PD deficiency severity, we report the construction, cloning and expression as well as the detailed kinetic and stability characterization of three purified clinical variants of G6PD that present in the Mexican population: G6PD Zacatecas (Class I), Vanua-Lava (Class II) and Viangchan (Class II). For all the G6PD mutants, we obtained low purification yield and altered kinetic parameters compared with Wild Type (WT). Our results show that the mutations, regardless of the distance from the active site where they are located, affect the catalytic properties and structural parameters and that these changes could be associated with the clinical presentation of the deficiency. Specifically, the structural characterization of the G6PD Zacatecas mutant suggests that the R257L mutation have a strong effect on the global stability of G6PD favoring an unstable active site. Using computational analysis, we offer a molecular explanation of the effects of these mutations on the active site. PMID:27213370

Identification of glucose 6 phosphate dehydrogenase mutations by ...

African Journals Online (AJOL)

Identification of glucose 6 phosphate dehydrogenase mutations by single strand conformation polymorphism and gene sequencing analysis. ... Subject: Six DNA samples from Turkish males confirmed to have G-6-PD deficiency where available for the study. Results: One subject was found to have an abnormal mobility shift ...

Glucose-6-phosphate dehydrogenase deficiency in Nigerian children.

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Olatundun Williams

Full Text Available Glucose-6-phosphate dehydrogenase (G6PD deficiency is the most common human enzymopathy and in Sub-Saharan Africa, is a significant cause of infection- and drug-induced hemolysis and neonatal jaundice. Our goals were to determine the prevalence of G6PD deficiency among Nigerian children of different ethnic backgrounds and to identify predictors of G6PD deficiency by analyzing vital signs and hematocrit and by asking screening questions about symptoms of hemolysis. We studied 1,122 children (561 males and 561 females aged 1 month to 15 years. The mean age was 7.4 ± 3.2 years. Children of Yoruba ethnicity made up the largest group (77.5% followed by those Igbo descent (10.6% and those of Igede (10.2% and Tiv (1.8% ethnicity. G6PD status was determined using the fluorescent spot method. We found that the overall prevalence of G6PD deficiency was 15.3% (24.1% in males, 6.6% in females. Yoruba children had a higher prevalence (16.9% than Igede (10.5%, Igbo (10.1% and Tiv (5.0% children. The odds of G6PD deficiency were 0.38 times as high in Igbo children compared to Yoruba children (p=0.0500. The odds for Igede and Tiv children were not significantly different from Yoruba children (p=0.7528 and 0.9789 respectively. Mean oxygen saturation, heart rate and hematocrit were not significantly different in G6PD deficient and G6PD sufficient children. The odds of being G6PD deficient were 2.1 times higher in children with scleral icterus than those without (p=0.0351. In conclusion, we determined the prevalence of G6PD deficiency in Nigerian sub-populations. The odds of G6PD deficiency were decreased in Igbo children compared to Yoruba children. There was no association between vital parameters or hematocrit and G6PD deficiency. We found that a history of scleral icterus may increase the odds of G6PD deficiency, but we did not exclude other common causes of icterus such as sickle cell disease or malarial infection.

Hypoxia-induced glucose-6-phosphate dehydrogenase overexpression and -activation in pulmonary artery smooth muscle cells: implication in pulmonary hypertension

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Chettimada, Sukrutha; Gupte, Rakhee; Rawat, Dhwajbahadur; Gebb, Sarah A.; McMurtry, Ivan F.

2014-01-01

Severe pulmonary hypertension is a debilitating disease with an alarmingly low 5-yr life expectancy. Hypoxia, one of the causes of pulmonary hypertension, elicits constriction and remodeling of the pulmonary arteries. We now know that pulmonary arterial remodeling is a consequence of hyperplasia and hypertrophy of pulmonary artery smooth muscle (PASM), endothelial, myofibroblast, and stem cells. However, our knowledge about the mechanisms that cause these cells to proliferate and hypertrophy in response to hypoxic stimuli is still incomplete, and, hence, the treatment for severe pulmonary arterial hypertension is inadequate. Here we demonstrate that the activity and expression of glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the pentose phosphate pathway, are increased in hypoxic PASM cells and in lungs of chronic hypoxic rats. G6PD overexpression and -activation is stimulated by H2O2. Increased G6PD activity contributes to PASM cell proliferation by increasing Sp1 and hypoxia-inducible factor 1α (HIF-1α), which directs the cells to synthesize less contractile (myocardin and SM22α) and more proliferative (cyclin A and phospho-histone H3) proteins. G6PD inhibition with dehydroepiandrosterone increased myocardin expression in remodeled pulmonary arteries of moderate and severe pulmonary hypertensive rats. These observations suggest that altered glucose metabolism and G6PD overactivation play a key role in switching the PASM cells from the contractile to synthetic phenotype by increasing Sp1 and HIF-1α, which suppresses myocardin, a key cofactor that maintains smooth muscle cell in contractile state, and increasing hypoxia-induced PASM cell growth, and hence contribute to pulmonary arterial remodeling and pathogenesis of pulmonary hypertension. PMID:25480333

Glucose-6-phosphate dehydrogenase deficiency; the single most ...

African Journals Online (AJOL)

Introduction: Glucose- 6-phosphate dehydrogenase deficiency is the most common enzymatic disorder of the red cell and an important risk factor for neonatal jaundice. Methodology: The aim of the study was to determine the incidence of G-6-PD deficiency among jaundiced neonates, and describe the associated morbidity ...

Glucose-6-phosphate dehydrogenase deficiency in neonatal hyperbilirubinaemia: Hacettepe experıence.

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Celik, H Tolga; Günbey, Ceren; Unal, Sule; Gümrük, Fatma; Yurdakök, Murat

2013-05-01

The aim of this study was to investigate the prevalence of glucose-6-phospate dehydrogenase (G6PD) deficiency in newborn infants with neonatal hyperbilirubinaemia and to compare the clinical features of G6PD-deficient and G6PD-normal newborn infants. A total of 4906 term and preterm neonates with indirect hyperbilirubinaemia were retrospectively evaluated according to demographic, neonatal features, bilirubin levels, erythrocyte G6PD levels, other risk factors and treatments. Among 4906 newborn infants with indirect hyperbilirubinaemia, 55 (1.12%) neonates were G6PD-deficient. In our study, no statistically significant difference was detected between G6PD-deficient and G6PD-normal infants in relation to the time of onset of jaundice, bilirubin levels and duration of phototherapy. However, the incidence of exchange transfusion in G6PD-deficient infants was 16.4% while it was only 3.3% in G6PD normal infants (P G6PD must be ordered to all newborns who are receiving phototherapy and especially to those who are coming from the high incident geographical regions and less responsive to phototherapy. © 2013 The Authors. Journal of Paediatrics and Child Health © 2013 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

Reduced glutathione and glutathione disulfide in the blood of glucose-6-phosphate dehydrogenase-deficient newborns.

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Gong, Zhen-Hua; Tian, Guo-Li; Huang, Qi-Wei; Wang, Yan-Min; Xu, Hong-Ping

2017-07-20

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is commonly detected during mass screening for neonatal disease. We developed a method to measure reduced glutathione (GSH) and glutathione disulfide (GSSG) using tandem mass spectrometry (MS/MS) for detecting G6PD deficiency. The concentration of GSH and the GSH/GSSG ratio in newborn dry-blood-spot (DBS) screening and in blood plus sodium citrate for test confirmation were examined by MS/MS using labeled glycine as an internal standard. G6PD-deficient newborns had a lower GSH content (242.9 ± 15.9 μmol/L)and GSH/GSSG ratio (14.9 ± 7.2) than neonatal controls (370.0 ± 53.2 μmol/L and 46.7 ± 19.6, respectively). Although the results showed a significance of P blood measured using MS/MS on the first day of sample preparation are consistent with G6PD activity and are helpful for diagnosing G6PD deficiency.

Comparison of Spectrophotometry, Chromate Inhibition, and Cytofluorometry Versus Gene Sequencing for Detection of Heterozygously Glucose-6-Phosphate Dehydrogenase-Deficient Females.

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Peters, Anna L; Veldthuis, Martijn; van Leeuwen, Karin; Bossuyt, Patrick M M; Vlaar, Alexander P J; van Bruggen, Robin; de Korte, Dirk; Van Noorden, Cornelis J F; van Zwieten, Rob

2017-11-01

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzyme deficiency worldwide. Detection of heterozygously deficient females can be difficult as residual activity in G6PD-sufficient red blood cells (RBCs) can mask deficiency. In this study, we compared accuracy of 4 methods for detection of G6PD deficiency in females. Blood samples from females more than 3 months of age were used for spectrophotometric measurement of G6PD activity and for determination of the percentage G6PD-negative RBCs by cytofluorometry. An additional sample from females suspected to have G6PD deficiency based on the spectrophotometric G6PD activity was used for measuring chromate inhibition and sequencing of the G6PD gene. Of 165 included females, 114 were suspected to have heterozygous deficiency. From 75 females, an extra sample was obtained. In this group, mutation analysis detected 27 heterozygously deficient females. The sensitivity of spectrophotometry, cytofluorometry, and chromate inhibition was calculated to be 0.52 (confidence interval [CI]: 0.32-0.71), 0.85 (CI: 0.66-0.96), and 0.96 (CI: 0.71-1.00, respectively, and the specificity was 1.00 (CI: 0.93-1.00), 0.88 (CI: 0.75-0.95), and 0.98 (CI: 0.89-1.00), respectively. Heterozygously G6PD-deficient females with a larger percentage of G6PD-sufficient RBCs are missed by routine methods measuring total G6PD activity. However, the majority of these females can be detected with both chromate inhibition and cytofluorometry.

Effects of iron chloride/zeolıte on G6PD of rainbow trout (Oncorhynchus mykiss)'s liver tissue

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Alak, Gonca; Uçar, Arzu; Parlak, Veysel; Kocaman, Esat Mahmut; Atamanalp, Muhammed

2016-04-01

Aquatic ecosystems have been negatively affected by the contamination of ground and surface waters as a result of various activities. Due to the ferrous chloride (FeCl2), which is used as the reducing agent for the organic synthesis reactions in the contamination of water column and sediment, iron salts may be very toxic for some aquatic organisms. In order to minimize these effects, natural products such as zeolite have been widely used in recently years. For this reason, rainbow trout were exposed to FeCl2 and/or zeolite ((FeCl2 (0.002 mg/l)(A), FeCl2+zeolite (0.002 mg/l+1 gr/l) (B), zeolite (1 gr/l) (C) and control (without FeCl2 and/or zeolite (D)). for 28 days and their oxidative stress responses were investigated. At the end of the treatment period, Glucose-6- phosphate dehydrogenase (G6PD) activity was determined in the samples taken from livers. G6PD values for liver tissues were found statistically important in the control and treatment groups (p<0.01).

The first evaluation of glucose-6-phosphate dehydrogenase deficiency (G6PD) gene mutation in malaria-endemic region at South Central Timor (SCT) district, Eastern Indonesia 2015-2016

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Hutagalung, J.; Kusnanto, H.; Supargiyono; Sadewa, A. H.; Satyagraha, A. W.

2018-03-01

Primaquine (PQ) is the only licensed drug effective against P. vivax for specific hypnozoites and as a key drug in the malaria elimination stage. However, PQ can cause severe hemolysis in G6PD deficient individuals. Unfortunately, few epidemiological data of these disorders was in Indonesia. This study aimed to assesses the prevalence and genotyping variant of G6PDd among the people on malaria-endemic. Blood samples from 555 unrelated subjects in eastern Indonesia were for G6PDd by quantitative test and PCR-RFLP-DNA sequencing. All protocols followed by Promega, Madison, USA. The prevalence of malaria and anemia was 32.6% (181/555) and 16% (89/555) with P. vivaxdominant species 52.5% (95/181), respectively. Overall, 16.6% (92/555) subjects were G6PD deficient, including 58.7% (54/92) females and 41.3% (38/92). Among the 92 cases G6PD deficient molecularly studied, the genotype variant Vanua Lava (T10883C) were detected dominant and unknown G6PD deficient (T-13.154-C) in 3 cases. It was high G6PD deficient in eastern Indonesia indicate that diagnosis and management of G6PD deficient are necessary. Obligatory anti-malaria doses for G6PD deficient individuals, population screening, are needed on endemic malaria in eastern Indonesia.

Data on how several physiological parameters of stored red blood cells are similar in glucose 6-phosphate dehydrogenase deficient and sufficient donors

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Vassilis L. Tzounakas

2016-09-01

Full Text Available This article contains data on the variation in several physiological parameters of red blood cells (RBCs donated by eligible glucose-6-phosphate dehydrogenase (G6PD deficient donors during storage in standard blood bank conditions compared to control, G6PD sufficient (G6PD+ cells. Intracellular reactive oxygen species (ROS generation, cell fragility and membrane exovesiculation were measured in RBCs throughout the storage period, with or without stimulation by oxidants, supplementation of N-acetylcysteine and energy depletion, following incubation of stored cells for 24 h at 37 °C. Apart from cell characteristics, the total or uric acid-dependent antioxidant capacity of the supernatant in addition to extracellular potassium concentration was determined in RBC units. Finally, procoagulant activity and protein carbonylation levels were measured in the microparticles population. Further information can be found in “Glucose 6-phosphate dehydrogenase deficient subjects may be better “storers” than donors of red blood cells” [1]. Keywords: G6PD deficiency, Red blood cell storage lesion, Oxidative stress, Cell fragility, Microparticles

[Evaluations of newborn screening program performance and enzymatic diagnosis of glucose-6-phosphate dehydrogenase deficiency in Guangzhou].

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Tang, F; Huang, Y L; Jiang, X; Jia, X F; Li, B; Feng, Y; Chen, Q Y; Tang, C F

2018-05-02

Objective: To reveal the molecular epidemiologic characteristics of glucose-6-phosphate dehydrogenase (G6PD) gene and to evaluate based on the genetic analysis the newborn screening program performance and enzymatic diagnosis of G6PD deficiency in Guangzhou. Methods: G6PD enzyme activities were measured by quantitative fluorescence assay in dry blood spots of 16 319 newborns(8 725 males, 7 594 females) 3-7 days after birth in Guangzhou Newborn Center. They were born in Guangzhou form Oct. 1 to 20, 2016. The cutoff value of G6PD was less than 2.6 U/g Hb in dry blood spots. G6PD deficiency was diagnosed when G6PDblood cells. Genetic analysis of G6PD gene was performed on the dry blood spot samples of 823 newborns (including positive 346, negative 477)with various levels of G6PD enzyme activities through fluorescence PCR melting curve analysis(FMCA) to detect 15 kinds of mutations reported to be common among Chinese.G6PD gene Sanger sequency was performed in seven highly suspicious patients with negative results by FMCA. Results: (1) Using the cutoff value of G6PDT, c.551C>T, c.835A>T hemizygote were found in 3 male's samples, respectively. (3) The estimated prevalence of harboring mutation was 6.0% in males and 13.5% in females according to rates of mutation in samples with various levels of G6PD enzyme activities. Six common mutations were c.1388G>A、c.1376G>T, c.95A> G, c.871G>A, c.1024C>T, c.392G>T, accounting for 95.5% of detected alleles .(4) based on results of G6PD gene analysis, the newborn scereening of G6PD deficiency with cutoff value G6PDblood cells were 95.5%, 97.2%, respectively. Conclusions: The prevalence of G6PD deficiency in males was 6.0% in Guangzhou. Six mutations c.1388G>A, c.1376G>T, c.95A>G, c.871G>A, c.1024C>T, c.392G>T accounted for 95.5%. The cutoff value of G6PD<2.6 U/g Hb innewborn screening program and the criteria of biochemical diagnosis could accurately identify G6PD deficiency . Combined with biochemical and molecular analysis will

Rasburicase-induced Hemolytic Anemia in an Adolescent With Unknown Glucose-6-Phosphate Dehydrogenase Deficiency.

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Akande, Manzilat; Audino, Anthony N; Tobias, Joseph D

2017-01-01

Rasburicase, used in the prevention and treatment of tumor lysis syndrome (TLS), may cause hemolytic anemia and methemoglobinemia in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency. Although routine screening for G6PD deficiency has been recommended, given the turnaround time for test results and the urgency to treat TLS, such screening may not be feasible. We report a case of rasburicase-induced hemolytic anemia without methemoglobinemia in an adolescent with T-cell lymphoblastic lymphoma, TLS, and previously unrecognized G6PD deficiency. Previous reports of hemolytic anemia with rasburicase are reviewed, mechanisms discussed, and preventative strategies presented.

Glucose-6-phosphate dehydrogenase Lodi844C: a study on its expression in blood cells and muscle.

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Ninfali, P; Bresolin, N; Baronciani, L; Fortunato, F; Comi, G; Magnani, M; Scarlato, G

1991-01-01

Glucose-6-phosphate dehydrogenase (G6PD) deficiency was found in erythrocytes, lymphocytes and muscle of an Italian male, whose family has lived for at least three generations in Lodi (Lombardy, northern Italy). The subject was hospitalized for myalgia and dark urine after intense physical exercise, but no sign of anemia and chronic hemolysis were present at rest. Family studies revealed that the mother and the maternal aunt had the same enzymopathy. The enzyme-specific activity in red blood cells was 15% of control and the kinetic properties were the following: slower electrophoretic mobility; biphasic pH activity curve; slightly reduced thermal stability, and increased utilization of the substrate analogs. The analysis of our patient's DNA showed a G----C mutation at nucleotide 844 which causes an Asp----His amino acid change in position 282. This is the same mutation found by De Vita et al. in the G6PD Seattle-like variant. However, by following a new convention, we labelled our variant as G6PD Lodi844C. As far as the muscle is concerned, we found that the enzyme-specific activity in this tissue was 14% of control values, but cultured myotubes and myoblasts revealed a normal level of G6PD as well as skin fibroblasts. On the contrary in the same type of cultured cells obtained from G6PD Mediterranean subjects, the G6PD activity was about 20% of normal. Our results complete the characterization of this mutant enzyme, demonstrate the expression of the deficit in muscle and describe the enzyme behaviour in cultured cells.

Prevalence of glucose-6-phosphate dehydrogenase deficiency and diagnostic challenges in 1500 immigrants in Denmark examined for haemoglobinopathies

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Warny, Marie; Klausen, Tobias Wirenfeldt; Petersen, Jesper

2015-01-01

Similar to the thalassaemia syndromes, glucose-6-phosphate dehydrogenase (G6PD) deficiency is highly prevalent in areas historically exposed to malaria. In the present study, we used quantitative and molecular methods to determine the prevalence of G6PD deficiency in a population of 1508 immigran...

Loss of peroxisomes causes oxygen insensitivity of the histochemical assay of glucose-6-phosphate dehydrogenase activity to detect cancer cells

NARCIS (Netherlands)

Frederiks, Wilma M.; Vreeling-Sindelárová, Heleen; van Noorden, Cornelis J. F.

2007-01-01

Oxygen insensitivity of carcinoma cells and oxygen sensitivity of non-cancer cells in the histochemical assay of glucose-6-phosphate dehydrogenase (G6PD) enables detection of carcinoma cells in unfixed cell smears or cryostat sections of biopsies. The metabolic background of oxygen insensitivity is

Molecular Characterization of Cosenza Mutation among Patients with Glucose-6-Phosphate Dehydrogenase Deficiency in huzestan Province, Southwest Iran

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Kazemi Nezhad, Seyed Reza; Fahmi, Fatemeh; Khatami, Saeid Reza; Musaviun, Mohsen

2011-01-01

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common hereditary enzymatic disorders in human, increases the vulnerability of erythrocytes to oxidative stress. It is also characterized by remarkable molecular and biochemical heterogeneity. According to previous investigations, G6PD Cosenza (G1376C) is a common G6PD mutation in some parts of . Therefore in the present study we have characterized mutation among G6PD deficient individuals in Khuzestan province. In order to identify G6PD Cosenza, we analyzed the G6PD gene in 64 samples out of 231 deficient individuals who had not G6PD Mediterranean mutation, using PCR- restriction fragment length polymorphism (RFLP) method. G6PD Cosenza mutation was found in 6 males of 231 samples, resulting in the relative rate of 2.6% and allele frequency of 0.023 among Khuzestanian G6PD deficient subjects. A comparison of these results with previous findings in some parts of suggests that G6PD Cosenza is a common mutation in Khuzestanian G6PD deficient individuals. PMID:23365477

Screening for glucose-6-phosphate dehydrogenase deficiency in neonates: a comparison between cord and peripheral blood samples.

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AlSaif, Saif; Ponferrada, Ma Bella; AlKhairy, Khalid; AlTawil, Khalil; Sallam, Adel; Ahmed, Ibrahim; Khawaji, Mohammed; AlHathlol, Khalid; Baylon, Beverly; AlSuhaibani, Ahmed; AlBalwi, Mohammed

2017-07-11

The use of cord blood in the neonatal screening for glucose-6-phosphate dehydrogenase (G6PD) deficiency is being done with increasing frequency but has yet to be adequately evaluated against the use of peripheral blood sample which is usually employed for confirmation. We sought to determine the incidence and gender distribution of G6PD deficiency, and compare the results of cord against peripheral blood in identifying G6PD DEFICIENCY neonates using quantitative enzyme activity assay. We carried out a retrospective and cross-sectional study employing review of primary hospital data of neonates born in a tertiary care center from January to December 2008. Among the 8139 neonates with cord blood G6PD assays, an overall incidence of 2% for G6PD deficiency was computed. 79% of these were males and 21% were females with significantly more deficient males (p blood samples (n = 1253) showed a significantly higher mean G6PD value for peripheral than cord blood (15.12 ± 4.52 U/g and 14.52 ± 4.43 U/g, respectively, p = 0.0008). However, the proportion of G6PD deficient neonates did not significantly differ in the two groups (p = 0.79). Sensitivity of cord blood in screening for G6PD deficiency, using peripheral G6PD assay as a gold standard was 98.6% with a NPV of 99.5%. There was no difference between cord and peripheral blood samples in discriminating between G6PD deficient and non-deficient neonates. A significantly higher mean peripheral G6PD assay reinforces the use of cord blood for neonatal screening since it has substantially low false negative results.

Glucose-6-Phosphate Dehydrogenase Enhances Antiviral Response through Downregulation of NADPH Sensor HSCARG and Upregulation of NF-κB Signaling

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Yi-Hsuan Wu

2015-12-01

Full Text Available Glucose-6-phosphate dehydrogenase (G6PD-deficient cells are highly susceptible to viral infection. This study examined the mechanism underlying this phenomenon by measuring the expression of antiviral genes—tumor necrosis factor alpha (TNF-α and GTPase myxovirus resistance 1 (MX1—in G6PD-knockdown cells upon human coronavirus 229E (HCoV-229E and enterovirus 71 (EV71 infection. Molecular analysis revealed that the promoter activities of TNF-α and MX1 were downregulated in G6PD-knockdown cells, and that the IκB degradation and DNA binding activity of NF-κB were decreased. The HSCARG protein, a nicotinamide adenine dinucleotide phosphate (NADPH sensor and negative regulator of NF-κB, was upregulated in G6PD-knockdown cells with decreased NADPH/NADP+ ratio. Treatment of G6PD-knockdown cells with siRNA against HSCARG enhanced the DNA binding activity of NF-κB and the expression of TNF-α and MX1, but suppressed the expression of viral genes; however, the overexpression of HSCARG inhibited the antiviral response. Exogenous G6PD or IDH1 expression inhibited the expression of HSCARG, resulting in increased expression of TNF-α and MX1 and reduced viral gene expression upon virus infection. Our findings suggest that the increased susceptibility of the G6PD-knockdown cells to viral infection was due to impaired NF-κB signaling and antiviral response mediated by HSCARG.

G6PD: The Test

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... a G6PD deficiency if a male inherits the single X chromosome with an altered gene. Since women have two X sex chromosomes, they inherit two ... deficiency. In addition, a mother may pass the single mutated gene to any male children. Rarely do women have two mutated gene copies ( homozygous ), which could ...

Data mining and pathway analysis of glucose-6-phosphate dehydrogenase with natural language processing

Science.gov (United States)

Chen, Long; Zhang, Chunhua; Wang, Yanling; Li, Yuqian; Han, Qiaoqiao; Yang, Huixin; Zhu, Yuechun

2017-01-01

Human glucose-6-phosphate dehydrogenase (G6PD) is a crucial enzyme in the pentose phosphate pathway, and serves an important role in biosynthesis and the redox balance. G6PD deficiency is a major cause of neonatal jaundice and acute hemolyticanemia, and recently, G6PD has been associated with diseases including inflammation and cancer. The aim of the present study was to conduct a search of the National Center for Biotechnology Information PubMed library for articles discussing G6PD. Genes that were identified to be associated with G6PD were recorded, and the frequency at which each gene appeared was calculated. Gene ontology (GO), pathway and network analyses were then performed. A total of 98 G6PD-associated genes and 33 microRNAs (miRNAs) that potentially regulate G6PD were identified. The 98 G6PD-associated genes were then sub-classified into three functional groups by GO analysis, followed by analysis of function, pathway, network, and disease association. Out of the 47 signaling pathways identified, seven were significantly correlated with G6PD-associated genes. At least two out of four independent programs identified the 33 miRNAs that were predicted to target G6PD. miR-1207-5P, miR-1 and miR-125a-5p were predicted by all four software programs to target G6PD. The results of the present study revealed that dysregulation of G6PD was associated with cancer, autoimmune diseases, and oxidative stress-induced disorders. These results revealed the potential roles of G6PD-regulated signaling and metabolic pathways in the etiology of these diseases. PMID:28627690

Molecular Characterization of Cosenza Mutation among Patients with Glucose-6-Phosphate Dehydrogenase Deficiency in Khuzestan Province, Southwest Iran

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Seyed Reza Kazemi Nezhad

2011-03-01

Full Text Available Glucose-6-phosphate dehydrogenase (G6PD deficiency is one of the most common hereditary enzymatic disorders in human, increases the vulnerability of erythrocytes to oxidative stress. It is also characterized by remarkable molecular and biochemical heterogeneity. According to previous investigations, G6PD Cosenza (G1376C is a common G6PD mutation in some parts of Iran. Therefore in the present study we have characterized Cosenza mutation among G6PD deficient individuals in Khuzestan province. In order to identify G6PD Cosenza, we analyzed the G6PD gene in 64 samples out of 231 deficient individuals who had not G6PD Mediterranean mutation, using PCR- restriction fragment length polymorphism (RFLP method. G6PD Cosenza mutation was found in 6 males of 231 samples, resulting in the relative rate of 2.6% and allele frequency of 0.023 among Khuzestanian G6PD deficient subjects. A comparison of these results with previous findings in some parts of Iran suggests that G6PD Cosenza is a common mutation in Khuzestanian G6PD deficient individuals

Point-of-care G6PD diagnostics for Plasmodium vivax malaria is a clinical and public health urgency.

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Baird, J Kevin

2015-12-14

Malaria caused by Plasmodium vivax threatens over 2 billion people globally and sickens tens of millions annually. Recent clinical evidence discredits the long-held notion of this infection as intrinsically benign revealing an often threatening course associated with mortality. Most acute attacks by this species derive from latent forms in the human liver called hypnozoites. Radical cure for P. vivax malaria includes therapy aimed both at the acute attack (blood schizontocidal) and against future attacks (hypnozoitocidal). The only hypnozoitocide available is primaquine, a drug causing life-threatening acute hemolytic anemia in patients with the inherited blood disorder glucose-6-phosphate dehydrogenase (G6PD) deficiency. This disorder affects 400 million people worldwide, at an average prevalence of 8 % in malaria-endemic nations. In the absence of certain knowledge regarding the G6PD status of patients infected by P. vivax, providers must choose between the risk of harm caused by primaquine and that caused by the parasite by withholding therapy. Resolving this dilemma requires the availability of point-of-care G6PD diagnostics practical for use in the impoverished rural tropics where the vast majority of malaria patients seek care.

Modulation of nuclear T3 binding by T3 in a human hepatocyte cell-line (Chang-liver) - T3 stimulation of cell growth but not of malic enzyme, glucose-6-phosphatdehydrogenase or 6-phosphogluconate-dehydrogenase

DEFF Research Database (Denmark)

Matzen, L E; Kristensen, S R; Kvetny, J

1991-01-01

The T3 modulation of nuclear T3 binding (NBT3), the T3 effect on cell growth, and the T3 and insulin effects on malic enzyme (ME), glucose-6-phosphat-dehydrogenase (G6PD) and 6-phosphogluconat-dehydrogenase (G6PD) were studied in a human hepatocyte cell-line (Chang-liver). T3 was bound to a high ...

Single Low Dose Primaquine (0.25 mg/kg Does Not Cause Clinically Significant Haemolysis in G6PD Deficient Subjects.

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Germana Bancone

Full Text Available Primaquine is the only drug consistently effective against mature gametocytes of Plasmodium falciparum. The transmission blocking dose of primaquine previously recommended was 0.75 mg/kg (adult dose 45 mg but its deployment was limited because of concerns over haemolytic effects in patients with glucose-6-phosphate dehydrogenase (G6PD deficiency. G6PD deficiency is an inherited X-linked enzymatic defect that affects an estimated 400 million people around the world with high frequencies (15-20% in populations living in malarious areas. To reduce transmission in low transmission settings and facilitate elimination of P. falciparum, the World Health Organization now recommends adding a single dose of 0.25 mg/kg (adult dose 15 mg to Artemisinin-based Combination Therapies (ACTs without G6PD testing. Direct evidence of the safety of this low dose is lacking. Adverse events and haemoglobin variations after this treatment were assessed in both G6PD normal and deficient subjects in the context of targeted malaria elimination in a malaria endemic area on the North-Western Myanmar-Thailand border where prevalence of G6PD deficiency (Mahidol variant approximates 15%.The tolerability and safety of primaquine (single dose 0.25 mg base/kg combined with dihydroartemisinin-piperaquine (DHA-PPQ given three times at monthly intervals was assessed in 819 subjects. Haemoglobin concentrations were estimated over the six months preceding the ACT + primaquine rounds of mass drug administration. G6PD deficiency was assessed with a phenotypic test and genotyping was performed in male subjects with deficient phenotypes and in all females. Fractional haemoglobin changes in relation to G6PD phenotype and genotype and primaquine round were assessed using linear mixed-effects models. No adverse events related to primaquine were reported during the trial. Mean fractional haemoglobin changes after each primaquine treatment in G6PD deficient subjects (-5.0%, -4.2% and -4

Present status of understanding on the G6PD deficiency and natural selection

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Tripathy V

2007-01-01

Full Text Available G6PD deficiency is a common hemolytic genetic disorder, particularly in the areas endemic to malaria. Individuals are generally asymptomatic and hemolytic anemia occurs when some anti-malarial drugs or other oxidizing chemicals are administered. It has been proposed that G6PD deficiency provides protection against malaria. Maintaining of G6PD deficient alleles at polymorphic proportions is complicated because of the X-linked nature of G6PD deficiency. A comprehensive review of the literature on the hypothesis of malarial protection and the nature of the selection is being presented. Most of the epidemiological, in vitro and in vivo studies report selection for G6PD deficiency. Analysis of the G6PD gene also reveals that G6PD-deficient alleles show some signatures of selection. However, the question of how this polymorphism is being maintained remains unresolved because the selection/fitness coefficients for the different genotypes in the two sexes have not been established. Prevalence of G6PD deficiency in Indian caste and tribal populations and the different variants reported has also been reviewed.

Glucose-6-phosphate dehydrogenase deficiency: an unusual cause of acute jaundice after paracetamol overdose.

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Phillpotts, Simon; Tash, Elliot; Sen, Sambit

2014-11-01

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the commonest human enzyme defect causing haemolytic anaemia after exposure to specific triggers. Paracetamol-induced haemolysis in G6PD deficiency is a rare complication and mostly reported in children. We report the first case (to the best of our knowledge) of acute jaundice without overt clinical features of a haemolytic crisis, in an otherwise healthy adult female following paracetamol overdose, due to previously undiagnosed G6PD deficiency. It is important that clinicians consider this condition when a patient presents following a paracetamol overdose with significant and disproportionate jaundice, without transaminitis or coagulopathy. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

[Neonatal screening of hemoglobinopathies and G6PD deficiency in Catalonia (Spain). Molecular study of sickle cell disease associated with alpha thalassemia and G6PD deficiency].

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Mañú Pereira, María Del Mar; Cabot, Anna; Martínez González, Ana; Sitjà Navarro, Eulalia; Cararach, Vicent; Sabrià, Josep; Boixaderas, Jordi; Teixidor, Roser; Bosch, Albert; López Vílchez, M Angeles; Martín Ibáñez, Itziar; Carrión, Teresa; Plaja, Pere; Sánchez, Mario; Vives Corrons, José Luis

2007-06-30

The prevalence of hemoglobinopathies and glucose-6-phosphate dehidrogenase (G6PD) deficiency in the Catalan neonatal population is increasing due to immigration. Coinheritance of more than a single RBC genetic defect is becoming more frequent and diagnostic pitfalls are also increasing. We intended to demonstrate the need to perform an early diagnosis of sickle cell disease (SCD) by means of neonatal screening, to establish the prevalence of SCD associated with alpha thalassemia and G6PD deficiency and to identify genotypes associated with sickle cell disease and G6PD deficiency. 4,020 blood samples from newborns were screened. For the screening of hemoglobinopathies the high performance liquid chromatography method was used and for G6PD deficiency the fluorescent spot test was employed. We studied the association between betaS gene and alpha thalassaemia del-3.7 Kb. SCD and G6PD deficiency genotypes were established. Prevalence of SCD in population at risk was 1/475 newborns. Prevalence of G6PD deficiency in population at risk was 1/43, and in autochthonous population was 1/527 newborns. In all the cases, sickle hemoglobin was confirmed by ARMS (amplification refractory mutation system). Association between betaS gene and alpha thalassaemia del-3.7 Kb was found in 32.2% of the samples, and an association between betaS gene and G6PD deficiency was observed in 7% of the samples. This study confirms the high prevalence of SCD and G6PD deficiency in population at risk as well as their genetic and clinical heterogeneity. The study of genotype/phenotype relationships allows a better knowledge of molecular mechanism and is useful to establish suitable criteria of diagnosis.

G6PD deficiency in Latin America: systematic review on prevalence and variants

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Monteiro, Wuelton M; Val, Fernando FA; Siqueira, André M; Franca, Gabriel P; Sampaio, Vanderson S; Melo, Gisely C; Almeida, Anne CG; Brito, Marcelo AM; Peixoto, Henry M; Fuller, Douglas; Bassat, Quique; Romero, Gustavo AS; Maria Regina F, Oliveira; Marcus Vinícius G, Lacerda

2014-01-01

Plasmodium vivax radical cure requires the use of primaquine (PQ), a drug that induces haemolysis in glucose-6-phosphate dehydrogenase deficient (G6PDd) individuals, which further hampers malaria control efforts. The aim of this work was to study the G6PDd prevalence and variants in Latin America (LA) and the Caribbean region. A systematic search of the published literature was undertaken in August 2013. Bibliographies of manuscripts were also searched and additional references were identified. Low prevalence rates of G6PDd were documented in Argentina, Bolivia, Mexico, Peru and Uruguay, but studies from Curaçao, Ecuador, Jamaica, Saint Lucia, Suriname and Trinidad, as well as some surveys carried out in areas of Brazil, Colombia and Cuba, have shown a high prevalence (> 10%) of G6PDd. The G6PD A-202A mutation was the variant most broadly distributed across LA and was identified in 81.1% of the deficient individuals surveyed. G6PDd is a frequent phenomenon in LA, although certain Amerindian populations may not be affected, suggesting that PQ could be safely used in these specific populations. Population-wide use of PQ as part of malaria elimination strategies in LA cannot be supported unless a rapid, accurate and field-deployable G6PDd diagnostic test is made available. PMID:25141282

G6PD deficiency in Latin America: systematic review on prevalence and variants

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Wuelton M Monteiro

2014-08-01

Full Text Available Plasmodium vivax radical cure requires the use of primaquine (PQ, a drug that induces haemolysis in glucose-6-phosphate dehydrogenase deficient (G6PDd individuals, which further hampers malaria control efforts. The aim of this work was to study the G6PDd prevalence and variants in Latin America (LA and the Caribbean region. A systematic search of the published literature was undertaken in August 2013. Bibliographies of manuscripts were also searched and additional references were identified. Low prevalence rates of G6PDd were documented in Argentina, Bolivia, Mexico, Peru and Uruguay, but studies from Curaçao, Ecuador, Jamaica, Saint Lucia, Suriname and Trinidad, as well as some surveys carried out in areas of Brazil, Colombia and Cuba, have shown a high prevalence (> 10% of G6PDd. The G6PD A-202A mutation was the variant most broadly distributed across LA and was identified in 81.1% of the deficient individuals surveyed. G6PDd is a frequent phenomenon in LA, although certain Amerindian populations may not be affected, suggesting that PQ could be safely used in these specific populations. Population-wide use of PQ as part of malaria elimination strategies in LA cannot be supported unless a rapid, accurate and field-deployable G6PDd diagnostic test is made available.

G6PD deficiency in Latin America: systematic review on prevalence and variants.

Science.gov (United States)

Monteiro, Wuelton M; Val, Fernando F A; Siqueira, André M; Franca, Gabriel P; Sampaio, Vanderson S; Melo, Gisely C; Almeida, Anne C G; Brito, Marcelo A M; Peixoto, Henry M; Fuller, Douglas; Bassat, Quique; Romero, Gustavo A S; Maria Regina F, Oliveira; Marcus Vinícius G, Lacerda

2014-08-01

Plasmodium vivax radical cure requires the use of primaquine (PQ), a drug that induces haemolysis in glucose-6-phosphate dehydrogenase deficient (G6PDd) individuals, which further hampers malaria control efforts. The aim of this work was to study the G6PDd prevalence and variants in Latin America (LA) and the Caribbean region. A systematic search of the published literature was undertaken in August 2013. Bibliographies of manuscripts were also searched and additional references were identified. Low prevalence rates of G6PDd were documented in Argentina, Bolivia, Mexico, Peru and Uruguay, but studies from Curaçao, Ecuador, Jamaica, Saint Lucia, Suriname and Trinidad, as well as some surveys carried out in areas of Brazil, Colombia and Cuba, have shown a high prevalence (> 10%) of G6PDd. The G6PD A-202A mutation was the variant most broadly distributed across LA and was identified in 81.1% of the deficient individuals surveyed. G6PDd is a frequent phenomenon in LA, although certain Amerindian populations may not be affected, suggesting that PQ could be safely used in these specific populations. Population-wide use of PQ as part of malaria elimination strategies in LA cannot be supported unless a rapid, accurate and field-deployable G6PDd diagnostic test is made available.

[Glucose-6-phosphate dehydrogenase deficiency in children: a case report].

Science.gov (United States)

Verdugo L, Patricia; Calvanese T, Marlene; Rodríguez V, Diego; Cárcamo C, Cassandra

2014-02-01

Glucose-6-phosphate dehydrogenase deficiency (G6PD deficiency) is the most common red blood cell (RBC) enzyme disorder. The decrease as well as the absence of the enzyme increase RBC vulnerability to oxidative stress caused by exposure to certain medications or intake of fava beans. Among the most common clinical manifestations of this condition, acute hemolysis, chronic hemolysis, neonatal hyperbilirubinemia, and an asymptomatic form are observed. To analyze the case of a child who presented hemolytic crisis due to favism. A 2 year and 7 month old boy with a history of hyperbilirubinemia during the newborn period with no apparent cause, no family history of hemolytic anemia or parental consanguinity. He presented a prolonged neonatal jaundice and severe anemia requiring RBC transfusion. An intake of fava beans 48 h prior to onset of symptoms was reported. G6PD qualitative determination was compatible with this enzyme deficiency. G6PD deficiency can be highly variable in its clinical presentation, so it is necessary to keep it in mind during the diagnosis of hemolytic anemia at any age.

Five novel glucose-6-phosphate dehydrogenase deficiency haplotypes correlating with disease severity

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Dallol Ashraf

2012-09-01

Full Text Available Abstract Background Glucose-6-phosphate dehydrogenase (G6PD, EC 1.1.1.49 deficiency is caused by one or more mutations in the G6PD gene on chromosome X. An association between enzyme levels and gene haplotypes remains to be established. Methods In this study, we determined G6PD enzyme levels and sequenced the coding region, including the intron-exon boundaries, in a group of individuals (163 males and 86 females who were referred to the clinic with suspected G6PD deficiency. The sequence data were analysed by physical linkage analysis and PHASE haplotype reconstruction. Results All previously reported G6PD missense changes, including the AURES, MEDITERRANEAN, A-, SIBARI, VIANGCHAN and ANANT, were identified in our cohort. The AURES mutation (p.Ile48Thr was the most common variant in the cohort (30% in males patients followed by the Mediterranean variant (p.Ser188Phe detectable in 17.79% in male patients. Variant forms of the A- mutation (p.Val68Met, p.Asn126Asp or a combination of both were detectable in 15.33% of the male patients. However, unique to this study, several of such mutations co-existed in the same patient as shown by physical linkage in males or PHASE haplotype reconstruction in females. Based on 6 non-synonymous variants of G6PD, 13 different haplotypes (13 in males, 8 in females were identified. Five of these were previously unreported (Jeddah A, B, C, D and E and were defined by previously unreported combinations of extant mutations where patients harbouring these haplotypes exhibited severe G6PD deficiency. Conclusions Our findings will help design a focused population screening approach and provide better management for G6PD deficiency patients.

Glucose-6-Phosphate Dehydrogenase Deficiency and Adrenal Hemorrhage in a Filipino Neonate with Hyperbilirubinemia

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Akira Ohishi

2013-05-01

Full Text Available We report on a Filipino neonate with early onset and prolonged hyperbilirubinemia who was delivered by a vacuum extraction due to a prolonged labor. Subsequent studies revealed adrenal hemorrhage and glucose-6-phosphate dehydrogenase (G6PD deficiency. It is likely that asphyxia and resultant hypoxia underlie the occurrence of adrenal hemorrhage and the clinical manifestation of G6PD deficiency and that the presence of the two events explains the early onset and prolonged hyperbilirubinemia of this neonate. Our results represent the importance of examining possible underlying factors for the development of severe, early onset, or prolonged hyperbilirubinemia.

Diagnostic performances of the fluorescent spot test for G6PD deficiency in newborns along the Thailand-Myanmar border: A cohort study.

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Thielemans, Laurence; Gornsawun, Gornpan; Hanboonkunupakarn, Borimas; Paw, Moo Kho; Porn, Pen; Moo, Paw Khu; Van Overmeire, Bart; Proux, Stephane; Nosten, François; McGready, Rose; Carrara, Verena I; Bancone, Germana

2018-01-01

Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an inherited enzymatic disorder associated with severe neonatal hyperbilirubinemia and acute haemolysis after exposure to certain drugs or infections. The disorder can be diagnosed phenotypically with a fluorescent spot test (FST), which is a simple test that requires training and basic laboratory equipment. This study aimed to assess the diagnostic performances of the FST used on umbilical cord blood by locally-trained staff and to compare test results of the neonates at birth with the results after one month of age. Methods : We conducted a cohort study on newborns at the Shoklo Malaria Research Unit, along the Thai-Myanmar border between January 2015 and May 2016. The FST was performed at birth on the umbilical cord blood by locally-trained staff and quality controlled by specialised technicians at the central laboratory. The FST was repeated after one month of age. Genotyping for common local G6PD mutations was carried out for all discrepant results. Results: FST was performed on 1521 umbilical cord blood samples. Quality control and genotyping revealed 10 misdiagnoses. After quality control, 10.7% of the males (84/786) and 1.2% of the females (9/735) were phenotypically G6PD deficient at birth. The FST repeated at one month of age or later diagnosed 8 additional G6PD deficient infants who were phenotypically normal at birth. Conclusions : This study shows the short-comings of the G6PD FST in neonatal routine screening and highlights the importance of training and quality control. A more conservative interpretation of the FST in male newborns could increase the diagnostic performances. Quantitative point-of-care tests might show higher sensitivity and specificity for diagnosis of G6PD deficiency on umbilical cord blood and should be investigated.

TLQP-21 protects human umbilical vein endothelial cells against high-glucose-induced apoptosis by increasing G6PD expression.

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Wei Zhang

Full Text Available Hyperglycemia causes oxidative stress that could damage vascular endothelial cells, leading to cardiovascular complications. The Vgf gene was identified as a nerve growth factor-responsive gene, and its protein product, VGF, is characterized by the presence of partially cleaved products. One of the VGF-derived peptides is TLQP-21, which is composed of 21 amino acids (residues 556-576. Past studies have reported that TLQP-21 could stimulate insulin secretion in pancreatic cells and protect these cells from apoptosis, which suggests that TLQP-21 has a potential function in diabetes therapy. Here, we explore the protective role of TLQP-21 against the high glucose-mediated injury of vascular endothelial cells. Using human umbilical vascular endothelial cells (HUVECs, we demonstrated that TLQP-21 (10 or 50 nM dose-dependently prevented apoptosis under high-glucose (30 mmol/L conditions (the normal glucose concentration is 5.6 mmol/L. TLQP-21 enhanced the expression of NAPDH, resulting in upregulation of glutathione (GSH and a reduction in the levels of reactive oxygen species (ROS. TLQP-21 also upregulated the expression of glucose-6-phosphate dehydrogenase (G6PD, which is known as the main source of NADPH. Knockdown of G6PD almost completely blocked the increase of NADPH induced by TLQP-21, indicating that TLQP-21 functions mainly through G6PD to promote NADPH generation. In conclusion, TLQP-21 could increase G6PD expression, which in turn may increase the synthesis of NADPH and GSH, thereby partially restoring the redox status of vascular endothelial cells under high glucose injury. We propose that TLQP-21 is a promising drug for diabetes therapy.

G6PD Deficiency and Antimalarial Efficacy for Uncomplicated Malaria in Bangladesh: A Prospective Observational Study.

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Benedikt Ley

Full Text Available The Bangladeshi national treatment guidelines for uncomplicated malaria follow WHO recommendations but without G6PD testing prior to primaquine administration. A prospective observational study was conducted to assess the efficacy of the current antimalarial policy.Patients with uncomplicated malaria, confirmed by microscopy, attending a health care facility in the Chittagong Hill Tracts, Bangladesh, were treated with artemether-lumefantrine (days 0-2 plus single dose primaquine (0.75mg/kg on day2 for P. falciparum infections, or with chloroquine (days 0-2 plus 14 days primaquine (3.5mg/kg total over 14 days for P. vivax infections. Hb was measured on days 0, 2 and 9 in all patients and also on days 16 and 30 in patients with P. vivax infection. Participants were followed for 30 days. The study was registered with the clinical trials website (NCT02389374.Between September 2014 and February 2015 a total of 181 patients were enrolled (64% P. falciparum, 30% P. vivax and 6% mixed infections. Median parasite clearance times were 22.0 (Interquartile Range, IQR: 15.2-27.3 hours for P. falciparum, 20.0 (IQR: 9.5-22.7 hours for P. vivax and 16.6 (IQR: 10.0-46.0 hours for mixed infections. All participants were afebrile within 48 hours, two patients with P. falciparum infection remained parasitemic at 48 hours. No patient had recurrent parasitaemia within 30 days. Adjusted male median G6PD activity was 7.82U/gHb. One male participant (1/174 had severe G6PD deficiency (<10% activity, five participants (5/174 had mild G6PD deficiency (10-60% activity. The Hb nadir occurred on day 2 prior to primaquine treatment in P. falciparum and P. vivax infected patients; mean fractional fall in Hb was -8.8% (95%CI -6.7% to -11.0% and -7.4% (95%CI: -4.5 to -10.4% respectively.The current antimalarial policy remains effective. The prevalence of G6PD deficiency was low. Main contribution to haemolysis in G6PD normal individuals was attributable to acute malaria rather

In Vitro Effects of Imidacloprid and Lambda-cyhalothrin on Capoeta capoeta umbla Kidney Glucose 6-Phosphate Dehydrogenase Enzyme

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Mahinur KIRICI

2015-03-01

Full Text Available Pesticide toxicity causes oxidative damage such as DNA damage, enhanced lipid peroxidation, the oxidation of protein sulfydryl groups and enzyme inactivation in the metabolism. In this study, we investigated the in vitro effects on glucose 6-phosphate dehydrogenase (E.C.1.1.49; G6PD from Capoeta capoeta umbla kidney of imidacloprid and lambda-cyhalothrin. For this purpose, the enzymewas purified from kidney of C. c. umbla with a specific activity of 11.26 EU mg-1 proteins and 22.7% yield using hemolysate preparation, ammonium sulfate precipitation and 2',5'-ADP Sepharose 4B affinity gel chromatography methods. In order to control the enzyme purification sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE was done. SDS-PAGE showed a single band for the enzyme. The results of this study suggested that imidacloprid and lambda-cyhalothrin have significant inhibition effect on the activity of G6PD in in vitro. In conclusion, lambda-cyhalothrin inhibits the enzyme activity more than imidacloprid.

Parental discussion of G6PD deficiency and child health: implications for clinical practice.

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Guan, Yue; Roter, Debra L; Huang, Aichu; Erby, Lori A H; Chien, Yin-Hsiu; Hwu, Wuh-Liang

2014-03-01

Parents are encouraged to discuss self-care with children affected by G6PD deficiency; however, little is known about the extent or impact of these discussions on the physical and psychosocial health of these children. The purpose of this study was to examine the nature of parental-child discussions of G6PD deficiency self-care and their relationship to child health. A quantitative cross-sectional survey of 178 Taiwanese parents of children with G6PD deficiency was conducted. The extent of parental-child self-care discussions was assessed in regards to coverage of nine key topics. Parent's G6PD deficiency status, knowledge of haemolytic anaemia symptoms and reported G6PD deficiency education from providers were examined as correlates of parental discussion. Child health was assessed with the child health questionnaire-parent form (Chinese version) and a 13-item haemolytic anaemia symptom list. Self-care discussions were positively correlated with parental G6PD deficiency status (β=2.08, p=0.03), accurate identification of haemolytic anaemia symptoms (β=0.18, p=0.01), the thoroughness and clarity of patient education (β=0.14, pchild age (β=1.04, pchild health (β=1.18, pchild G6PD deficiency self-care discussions are associated with better child health, and parental involvement in these discussions is facilitated by the thoroughness and clarity of patient education received from providers.

Frequency of G6PD Mediterranean in individuals with and without malaria in Southern Pakistan.

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Moiz, Bushra; Arshad, Haroon Muhammad; Raheem, Ahmed; Hayat, Hasan; Karim Ghanchi, Najia; Beg, M Asim

2017-10-24

Pakistan has an estimated annual burden of 1.5 million malaria cases. The current situation calls for an effective malaria control and eradication programme in this country. Currently, primaquine is an attractive option for eliminating reservoirs of Plasmodium vivax hypnozoites and killing gametocytes of Plasmodium falciparum. However, this drug causes haemolysis in individuals who are glucose-6-phosphate (G6PD) deficient. It is important to map G6PD deficiency and malaria distribution in Pakistan to design an effective malaria eradication regimen. Frequency of G6PD deficiency (G6PDd) in malaria patients has not been reported from Pakistan in any meaningful way. The purpose of this study was to evaluate the frequency of G6PD c.563C>T (G6PD Mediterranean) in male individuals with and without falciparum malaria. Two hundred and ten archived DNA samples from males (110 from falciparum malaria patients and 100 from healthy individuals) were utilized in this study. Healthy blood donors were selected based on stringent pre-defined criteria. Patients were confirmed for malaria parasites on microscopy and or immune chromatographic assay detecting P. falciparum histidine-rich protein 2. Parasitaemia was also computed. DNA samples were tested for G6PD c.563C>T mutation through PCR-RFLP according to the previously defined protocol and its allelic frequency was computed. G6PD c.563C>T was observed in four of 110 patients with falciparum malaria and in two of 100 healthy donors. Mean (± SD) haemoglobin, median (IQR) platelet and median (IQR) parasite count in G6PD-deficient malaria-patients were 8.9 ± 0.9 g/dL, 124 × 109/L (IQR 32, 171) and 57,920/μL of blood (IQR 12,920, 540,000) respectively. Cumulative allelic frequency for G6PD 563c.C>T was 0.0285 detected in 6 of 210 X-chromosomes in Southern Pakistan. Frequency for this G6PD allele was 0.0364 in malaria-patients and 0.0200 in healthy individuals. Large studies including females are needed to elucidate the true

Simultaneous demonstration of acid phosphatase and glucose-6-phosphate dehydrogenase in mouse hepatocytes. A novel electron-microscopic dual staining enzyme-cytochemistry

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S Matsubara

2010-01-01

Full Text Available Acid phosphatase (ACPase and glucose-6-phosphate dehydrogenase (G6PD play important roles in cell biology/disease pathophysiology in various organs including the liver. The purpose of the present report is to introduce a new enzymecytochemical method to simultaneously demonstrate the subcellular localization of ACPase and G6PD within the same hepatocyte in the mouse liver. The ultrastructural localization of ACPase and G6PD were demonstrated, with concomitant use of the cerium method and the copper-ferrocyanide method, respectively. ACPase labelings were localized in the lysosomes, and G6PD labelings were visible in the cytoplasm and on the cytosolic side of the endoplasmic reticulum of the hepatocyte. This novel double staining procedure may be a useful histochemical tool for the study of liver functions in both physiological and pathological conditions.

Review of key knowledge gaps in glucose-6-phosphate dehydrogenase deficiency detection with regard to the safe clinical deployment of 8-aminoquinoline treatment regimens: a workshop report.

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von Seidlein, Lorenz; Auburn, Sarah; Espino, Fe; Shanks, Dennis; Cheng, Qin; McCarthy, James; Baird, Kevin; Moyes, Catherine; Howes, Rosalind; Ménard, Didier; Bancone, Germana; Winasti-Satyahraha, Ari; Vestergaard, Lasse S; Green, Justin; Domingo, Gonzalo; Yeung, Shunmay; Price, Ric

2013-03-27

The diagnosis and management of glucose-6-phosphate dehydrogenase (G6PD) deficiency is a crucial aspect in the current phases of malaria control and elimination, which will require the wider use of 8-aminoquinolines for both reducing Plasmodium falciparum transmission and achieving the radical cure of Plasmodium vivax. 8-aminoquinolines, such as primaquine, can induce severe haemolysis in G6PD-deficient individuals, potentially creating significant morbidity and undermining confidence in 8-aminoquinoline prescription. On the other hand, erring on the side of safety and excluding large numbers of people with unconfirmed G6PD deficiency from treatment with 8-aminoquinolines will diminish the impact of these drugs. Estimating the remaining G6PD enzyme activity is the most direct, accessible, and reliable assessment of the phenotype and remains the gold standard for the diagnosis of patients who could be harmed by the administration of primaquine. Genotyping seems an unambiguous technique, but its use is limited by cost and the large range of recognized G6PD genotypes. A number of enzyme activity assays diagnose G6PD deficiency, but they require a cold chain, specialized equipment, and laboratory skills. These assays are impractical for care delivery where most patients with malaria live. Improvements to the diagnosis of G6PD deficiency are required for the broader and safer use of 8-aminoquinolines to kill hypnozoites, while lower doses of primaquine may be safely used to kill gametocytes without testing. The discussions and conclusions of a workshop conducted in Incheon, Korea in May 2012 to review key knowledge gaps in G6PD deficiency are reported here.

Isoniazid acetylating phenotype in patients with paracoccidioidomycosis and its relationship with serum sulfadoxin levels, glucose-6-phosphate dehydrogenase and glutathione reductase activities

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Benedito Barraviera

1991-06-01

Full Text Available The authors evaluated the isoniazid acetylating phenotype and measured hematocrit, hemoglobin, glucose-6-phosphate dehydrogenase and glutathione reductase activities plus serum sulfadoxin levels in 39 patients with paracoccidioidomycosis (33 males and 6 females aged 17 to 58 years. Twenty one (53.84% of the patients presented a slow acetylatingphenotype and 18(46.16% a fast acetylating phenotype. Glucose-6-phosphate- dehydrogenase (G6PD acti vity was decreased in 5(23.80% slow acetylators and in 4(22.22% fast acetylators. Glutathione reductase activity was decreased in 14 (66.66% slow acetylators and in 12 (66.66% fast acetylators. Serum levels of free and total sulfadoxin Were higher in slow acetylator (p Os autores avaliaram o fenótipo acetilador da isoniazida, hematócrito, hemoglobina, atividade da glicose-6- fosfato desidrogenase, glutationa redutase e os níveis séricos de sulfadoxina de 39 doentes com paracoccidíoidomicose, senão 33 do sexo masculino e 6 do feminino, com idades compreendidas entre 17 e 58 anos. Vinte e um (53,84% doentes apresentaram fenótipo acetilador lento e 18 (46,16% rápido. A atividade da glicose-6-fosfato desidrogenase (G6PD esteve diminuída em 5 (23,80% acetiladores lentos e 4 (22,22% rápidos. A atividade da glutationa redutase esteve diminuída em 14 (66,66% acetiladores lentos e 12 (66,66% rápidos. Os níveis séricos de sulfadoxina livre e total foram maiores nos acetiladores lentos (p < 0,02. A análise dos resultados permite concluir que os níveis séricos de sulfadoxina relaciona-se com o fenótipo acetilador. Além disso, os níveis estiveram sempre acima de 50 µg/ml, níveis estes considerados terapêuticos. Por outro lado, a deficiência de glutationa redutase pode estar relacionada com a má absorção intestinal de nutrientes, entre eles riboflavina, vitamina precursora de FAD.

Population screening for glucose-6-phosphate dehydrogenase deficiencies in Isabel Province, Solomon Islands, using a modified enzyme assay on filter paper dried bloodspots

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Landry Losi

2010-08-01

Full Text Available Abstract Background Glucose-6-phosphate dehydrogenase deficiency poses a significant impediment to primaquine use for the elimination of liver stage infection with Plasmodium vivax and for gametocyte clearance, because of the risk of life-threatening haemolytic anaemia that can occur in G6PD deficient patients. Although a range of methods for screening G6PD deficiency have been described, almost all require skilled personnel, expensive laboratory equipment, freshly collected blood, and are time consuming; factors that render them unsuitable for mass-screening purposes. Methods A published WST8/1-methoxy PMS method was adapted to assay G6PD activity in a 96-well format using dried blood spots, and used it to undertake population screening within a malaria survey undertaken in Isabel Province, Solomon Islands. The assay results were compared to a biochemical test and a recently marketed rapid diagnostic test. Results Comparative testing with biochemical and rapid diagnostic test indicated that results obtained by filter paper assay were accurate providing that blood spots were assayed within 5 days when stored at ambient temperature and 10 days when stored at 4 degrees. Screening of 8541 people from 41 villages in Isabel Province, Solomon Islands revealed the prevalence of G6PD deficiency as defined by enzyme activity Conclusions The assay enabled simple and quick semi-quantitative population screening in a malaria-endemic region. The study indicated a high prevalence of G6PD deficiency in Isabel Province and highlights the critical need to consider G6PD deficiency in the context of P. vivax malaria elimination strategies in Solomon Islands, particularly in light of the potential role of primaquine mass drug administration.

Prevalence of glucose-6-phosphate dehydrogenase deficiency and sickle cell trait among blood donors in Riyadh

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Alabdulaali Mohammed

2010-01-01

Full Text Available Background and Aims: Blood donation from glucose-6-phosphate dehydrogenase (G6PD-deficient and sickle cell trait (SCT donors might alter the quality of the donated blood during processing, storage or in the recipient′s circulatory system. The aim of this study was to determine the prevalence of G6PD deficiency and SCT among blood donors coming to King Khalid University Hospital (KKUH in Riyadh. It was also reviewed the benefits and risks of transfusing blood from these blood donors. Materials and Methods: This cross-sectional study was conducted on 1150 blood samples obtained from blood donors that presented to KKUH blood bank during the period April 2006 to May 2006. All samples were tested for Hb-S by solubility test, alkaline gel electrophoresis; and for G6PD deficiency, by fluorescent spot test. Results: Out of the 1150 donors, 23 (2% were diagnosed for SCT, 9 (0.78% for G6PD deficiency and 4 (0.35% for both conditions. Our prevalence of SCT and G6PD deficiency is higher than that of the general population of Riyadh. Conclusion: We recommend to screen all units for G6PD deficiency and sickle cell trait and to defer donations from donors with either of these conditions, unless if needed for special blood group compatibility, platelet apheresis or if these are likely to affect the blood bank inventory. If such blood is to be used, special precautions need to be undertaken to avoid complications in high-risk recipients.

Diagnostic performances of the fluorescent spot test for G6PD deficiency in newborns along the Thailand-Myanmar border: A cohort study [version 1; referees: 2 approved

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Laurence Thielemans

2018-01-01

Full Text Available Background: Glucose-6-phosphate dehydrogenase (G6PD deficiency is an inherited enzymatic disorder associated with severe neonatal hyperbilirubinemia and acute haemolysis after exposure to certain drugs or infections. The disorder can be diagnosed phenotypically with a fluorescent spot test (FST, which is a simple test that requires training and basic laboratory equipment. This study aimed to assess the diagnostic performances of the FST used on umbilical cord blood by locally-trained staff and to compare test results of the neonates at birth with the results after one month of age. Methods: We conducted a cohort study on newborns at the Shoklo Malaria Research Unit, along the Thai-Myanmar border between January 2015 and May 2016. The FST was performed at birth on the umbilical cord blood by locally-trained staff and quality controlled by specialised technicians at the central laboratory. The FST was repeated after one month of age. Genotyping for common local G6PD mutations was carried out for all discrepant results. Results: FST was performed on 1521 umbilical cord blood samples. Quality control and genotyping revealed 10 misdiagnoses. After quality control, 10.7% of the males (84/786 and 1.2% of the females (9/735 were phenotypically G6PD deficient at birth. The FST repeated at one month of age or later diagnosed 8 additional G6PD deficient infants who were phenotypically normal at birth. Conclusions: This study shows the short-comings of the G6PD FST in neonatal routine screening and highlights the importance of training and quality control. A more conservative interpretation of the FST in male newborns could increase the diagnostic performances. Quantitative point-of-care tests might show higher sensitivity and specificity for diagnosis of G6PD deficiency on umbilical cord blood and should be investigated.

Using G6PD tests to enable the safe treatment of Plasmodium vivax infections with primaquine on the Thailand-Myanmar border: A cost-effectiveness analysis.

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Angela Devine

2017-05-01

Full Text Available Primaquine is the only licensed antimalarial for the radical cure of Plasmodium vivax infections. Many countries, however, do not administer primaquine due to fear of hemolysis in those with glucose-6-phosphate dehydrogenase (G6PD deficiency. In other settings, primaquine is given without G6PD testing, putting patients at risk of hemolysis. New rapid diagnostic tests (RDTs offer the opportunity to screen for G6PD deficiency prior to treatment with primaquine. Here we assessed the cost-effectiveness of using G6PD RDTs on the Thailand-Myanmar border and provide the model as an online tool for use in other settings.Decision tree models for the management of P. vivax malaria evaluated the costs and disability-adjusted life-years (DALYs associated with recurrences and primaquine-induced hemolysis from a health care provider perspective. Screening with G6PD RDTs before primaquine use was compared to (1 giving chloroquine alone and (2 giving primaquine without screening. Data were taken from a recent study on the impact of primaquine on P. vivax recurrences and a literature review. Compared to the use of chloroquine alone, the screening strategy had similar costs while averting 0.026 and 0.024 DALYs per primary infection in males and females respectively. Compared to primaquine administered without screening, the screening strategy provided modest cost savings while averting 0.011 and 0.004 DALYs in males and females respectively. The probabilistic sensitivity analyses resulted in a greater than 75% certainty that the screening strategy was cost-effective at a willingness to pay threshold of US$500, which is well below the common benchmark of per capita gross domestic product for Myanmar.In this setting G6PD RDTs could avert DALYs by reducing recurrences and reducing hemolytic risk in G6PD deficient patients at low costs or cost savings. The model results are limited by the paucity of data available in the literature for some parameter values

Noninferiority of glucose-6-phosphate dehydrogenase deficiency diagnosis by a point-of-care rapid test vs the laboratory fluorescent spot test demonstrated by copper inhibition in normal human red blood cells.

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Baird, J Kevin; Dewi, Mewahyu; Subekti, Decy; Elyazar, Iqbal; Satyagraha, Ari W

2015-06-01

Tens of millions of patients diagnosed with vivax malaria cannot safely receive primaquine therapy against repeated attacks caused by activation of dormant liver stages called hypnozoites. Most of these patients lack access to screening for glucose-6-phosphate dehydrogenase (G6PD) deficiency, a highly prevalent disorder causing serious acute hemolytic anemia with primaquine therapy. We optimized CuCl inhibition of G6PD in normal red blood cells (RBCs) to assess G6PD diagnostic technologies suited to point of care in the impoverished rural tropics. The most widely applied technology for G6PD screening-the fluorescent spot test (FST)-is impractical in that setting. We evaluated a new point-of-care G6PD screening kit (CareStart G6PD, CSG) against FST using graded CuCl treatments to simulate variable hemizygous states, and varying proportions of CuCl-treated RBC suspensions to simulate variable heterozygous states of G6PD deficiency. In experiments double-blinded to CuCl treatment, technicians reading FST and CSG test (n = 269) classified results as positive or negative for deficiency. At G6PD activity ≤40% of normal (n = 112), CSG test was not inferior to FST in detecting G6PD deficiency (P = 0.003), with 96% vs 90% (P = 0.19) sensitivity and 75% and 87% (P = 0.01) specificity, respectively. The CSG test costs less, requires no specialized equipment, laboratory skills, or cold chain for successful application, and performs as well as the FST standard of care for G6PD screening. Such a device may vastly expand access to primaquine therapy and aid in mitigating the very substantial burden of morbidity and mortality imposed by the hypnozoite reservoir of vivax malaria. Copyright © 2015 Elsevier Inc. All rights reserved.

What is the role of the second "structural" NADP+-binding site in human glucose 6-phosphate dehydrogenase?

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Wang, Xiao-Tao; Chan, Ting Fai; Lam, Veronica M S; Engel, Paul C

2008-08-01

Human glucose 6-phosphate dehydrogenase, purified after overexpression in E. coli, was shown to contain one molecule/subunit of acid-extractable "structural" NADP+ and no NADPH. This tightly bound NADP+ was reduced by G6P, presumably following migration to the catalytic site. Gel-filtration yielded apoenzyme, devoid of bound NADP+ but, surprisingly, still fully active. Mr of the main component of "stripped" enzyme by gel filtration was approximately 100,000, suggesting a dimeric apoenzyme (subunit Mr = 59,000). Holoenzyme also contained tetramer molecules and, at high protein concentration, a dynamic equilibrium gave an apparent intermediate Mr of 150 kDa. Fluorescence titration of the stripped enzyme gave the K d for structural NADP+ as 37 nM, 200-fold lower than for "catalytic" NADP+. Structural NADP+ quenches 91% of protein fluorescence. At 37 degrees C, stripped enzyme, much less stable than holoenzyme, inactivated irreversibly within 2 d. Inactivation at 4 degrees C was partially reversed at room temperature, especially with added NADP+. Apoenzyme was immediately active, without any visible lag, in rapid-reaction studies. Human G6PD thus forms active dimer without structural NADP+. Apparently, the true role of the second, tightly bound NADP+ is to secure long-term stability. This fits the clinical pattern, G6PD deficiency affecting the long-lived non-nucleate erythrocyte. The Kd values for two class I mutants, G488S and G488V, were 273 nM and 480 nM, respectively (seven- and 13-fold elevated), matching the structural prediction of weakened structural NADP+ binding, which would explain decreased stability and consequent disease. Preparation of native apoenzyme and measurement of Kd constant for structural NADP+ will now allow quantitative assessment of this defect in clinical G6PD mutations.

Mutations of Glucose-6-Phosphate Dehydrogenase Durham, Santa-Maria and A+ Variants Are Associated with Loss Functional and Structural Stability of the Protein

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Gómez-Manzo, Saúl; Marcial-Quino, Jaime; Vanoye-Carlo, America; Enríquez-Flores, Sergio; De la Mora-De la Mora, Ignacio; González-Valdez, Abigail; García-Torres, Itzhel; Martínez-Rosas, Víctor; Sierra-Palacios, Edgar; Lazcano-Pérez, Fernando; Rodríguez-Bustamante, Eduardo; Arreguin-Espinosa, Roberto

2015-01-01

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzymopathy in the world. More than 160 mutations causing the disease have been identified, but only 10% of these variants have been studied at biochemical and biophysical levels. In this study we report on the functional and structural characterization of three naturally occurring variants corresponding to different classes of disease severity: Class I G6PD Durham, Class II G6PD Santa Maria, and Class III G6PD A+. The results showed that the G6PD Durham (severe deficiency), and the G6PD Santa Maria and A+ (less severe deficiency) (Class I, II and III, respectively) affect the catalytic efficiency of these enzymes, are more sensitive to temperature denaturing, and affect the stability of the overall protein when compared to the wild type WT-G6PD. In the variants, the exposure of more and buried hydrophobic pockets was induced and monitored with 8-Anilinonaphthalene-1-sulfonic acid (ANS) fluorescence, directly affecting the compaction of structure at different levels and probably reducing the stability of the protein. The degree of functional and structural perturbation by each variant correlates with the clinical severity reported in different patients. PMID:26633385

Mutations of Glucose-6-Phosphate Dehydrogenase Durham, Santa-Maria and A+ Variants Are Associated with Loss Functional and Structural Stability of the Protein

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Saúl Gómez-Manzo

2015-12-01

Full Text Available Glucose-6-phosphate dehydrogenase (G6PD deficiency is the most common enzymopathy in the world. More than 160 mutations causing the disease have been identified, but only 10% of these variants have been studied at biochemical and biophysical levels. In this study we report on the functional and structural characterization of three naturally occurring variants corresponding to different classes of disease severity: Class I G6PD Durham, Class II G6PD Santa Maria, and Class III G6PD A+. The results showed that the G6PD Durham (severe deficiency, and the G6PD Santa Maria and A+ (less severe deficiency (Class I, II and III, respectively affect the catalytic efficiency of these enzymes, are more sensitive to temperature denaturing, and affect the stability of the overall protein when compared to the wild type WT-G6PD. In the variants, the exposure of more and buried hydrophobic pockets was induced and monitored with 8-Anilinonaphthalene-1-sulfonic acid (ANS fluorescence, directly affecting the compaction of structure at different levels and probably reducing the stability of the protein. The degree of functional and structural perturbation by each variant correlates with the clinical severity reported in different patients.

Clonal evolution following chemotherapy-induced stem cell depletion in cats heterozygous for glucose-6-phosphate dehydrogenase

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Abkowitz, J.L.; Ott, R.M.; Holly, R.D.; Adamson, J.W.

1988-01-01

The number of hematopoietic stem cells necessary to support normal hematopoiesis is not known but may be small. If so, the depletion or damage of such cells could result in apparent clonal dominance. To test this hypothesis, dimethylbusulfan [2 to 4 mg/kg intravenously (IV) x 3] was given to cats heterozygous for the X-linked enzyme glucose-6-phosphate dehydrogenase (G-6-PD). These cats were the daughters of domestic X Geoffroy parents. After the initial drug-induced cytopenias (2 to 4 weeks), peripheral blood counts and the numbers of marrow progenitors detected in culture remained normal, although the percentages of erythroid burst-forming cells (BFU-E) and granulocyte/macrophage colony-forming cells (CFU-GM) in DNA synthesis increased, as determined by the tritiated thymidine suicide technique. In three of six cats treated, a dominance of Geoffroy-type G-6-PD emerged among the progenitor cells, granulocytes, and RBCs. These skewed ratios of domestic to Geoffroy-type G-6-PD have persisted greater than 3 years. No changes in cell cycle kinetics or G-6-PD phenotypes were noted in similar studies in six control cats. These data suggest that clonal evolution may reflect the depletion or damage of normal stem cells and not only the preferential growth and dominance of neoplastic cells

Is GERD a Factor in Osteonecrosis of the Jaw? Evidence of Pathology Linked to G6PD Deficiency and Sulfomucins

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Stephanie Seneff

2016-01-01

Full Text Available Osteonecrosis of the jaw (ONJ, a rare side effect of bisphosphonate therapy, is a debilitating disorder with a poorly understood etiology. FDA’s Adverse Event Reporting System (FAERS provides the opportunity to investigate this disease. Our goals were to analyze FAERS data to discover possible relationships between ONJ and specific conditions and drugs and then to consult the scientific literature to deduce biological explanations. Our methodology revealed a very strong association between gastroesophageal reflux and bisphosphonate-induced ONJ, suggesting acidosis as a key factor. Overgrowth of acidophilic species, particularly Streptococcus mutans, in the oral microbiome in the context of insufficient acid buffering due to impaired salivary glands maintains the low pH that sustains damage to the mucosa. Significant associations between ONJ and adrenal insufficiency, vitamin C deficiency, and Sjögren’s syndrome were found. Glucose 6 phosphate dehydrogenase (G6PD deficiency can explain much of the pathology. An inability to maintain vitamin C and other antioxidants in the reduced form leads to vascular oxidative damage and impaired adrenal function. Thus, pathogen-induced acidosis, hypoxia, and insufficient antioxidant defenses together induce ONJ. G6PD deficiency and adrenal insufficiency are underlying factors. Impaired supply of adrenal-derived sulfated sterols such as DHEA sulfate may drive the disease process.

Mediterranean glucose-6-phosphate dehydrogenase (G6PDC563T) mutation among jordanian females with acute hemolytic crisis

International Nuclear Information System (INIS)

Jabbar, A.A.; Kanakiri, N.; Kamil, M.; Rimawi, H.S.A.

2010-01-01

To evaluate the G6PDC563T Mediterranean mutation among Jordanian females who were admitted to Princess Rahma Teaching Hospital (PRTH) with/or previous history of favism. Study Design: A descriptive study. Place and Duration of Study: Jordanian University of Science and Technology and PRTH, from October 2003 to October 2004. Methodology: After obtaining approval from the Ethics Committee of Jordanian University of Science and Technology, a total of 32 females were included in this study. Samples from 15 healthy individual females were used as a negative control. Blood samples from these patients were collected and analyzed by allele-specific polymerase chain reaction (AS-PCR) to determine the G6PDC563T mutation. Results: Twenty one out of 32 patients were found to be G6PDC563T Mediterranean mutation (65.6%) positive. Three out of 21 patients were homozygous and remaining 18 were heterozygous for G6PDC563T Mediterranean mutation. Eleven (34.4%) out of 32 patients were found to be negative for G6PDC563T mutation indicating the presence of other G6PD mutations in the study sample. Conclusion: G6PDC563T Mediterranean mutation accounted for 65.6% of the study sample with favism in the North of Jordan. There is likely to be another G6PD deficiency variant implicated in acute hemolytic crisis (favism). (author)

Purification and investigation of some kinetic properties of glucose-6-phosphate dehydrogenase from parsley (Petroselinum hortense) leaves.

Science.gov (United States)

Coban, T Abdül Kadir; Ciftçi, Mehmet; Küfrevioğlu, O Irfan

2002-05-01

In this study, glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate: NADP+ oxidoreductase, EC 1.1.1.49; G6PD) was purified from parsley (Petroselinum hortense) leaves, and analysis of the kinetic behavior and some properties of the enzyme were investigated. The purification consisted of three steps: preparation of homogenate, ammonium sulfate fractionation, and DEAE-Sephadex A50 ion exchange chromatography. The enzyme was obtained with a yield of 8.79% and had a specific activity of 2.146 U (mg protein)(-1). The overall purification was about 58-fold. Temperature of +4 degrees C was maintained during the purification process. Enzyme activity was spectrophotometrically measured according to the Beutler method, at 340 nm. In order to control the purification of enzyme, SDS-polyacrylamide gel electrophoresis was carried out in 4% and 10% acrylamide for stacking and running gel, respectively. SDS-polyacrylamide gel electrophoresis showed a single band for enzyme. The molecular weight was found to be 77.6 kDa by Sephadex G-150 gel filtration chromatography. A protein band corresponding to a molecular weight of 79.3 kDa was obtained on SDS-polyacrylamide gel electrophoresis. For the enzymes, the stable pH, optimum pH, and optimum temperature were found to be 6.0, 8.0, and 60 degrees C, respectively. Moreover, KM and Vmax values for NADP+ and G6-P at optimum pH and 25 degrees C were determined by means of Lineweaver-Burk graphs. Additionally, effects of streptomycin sulfate and tetracycline antibiotics were investigated for the enzyme activity of glucose-6-phosphate dehydrogenase in vitro.

Glucose-6-Phosphate Dehydrogenase Deficiency A− Variant in Febrile Patients in Haiti

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Carter, Tamar E.; Maloy, Halley; von Fricken, Michael; St. Victor, Yves; Romain, Jean R.; Okech, Bernard A.; Mulligan, Connie J.

2014-01-01

Haiti is one of two remaining malaria-endemic countries in the Caribbean. To decrease malaria transmission in Haiti, primaquine was recently added to the malaria treatment public health policy. One limitation of primaquine is that, at certain doses, primaquine can cause hemolytic anemia in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency (G6PDd). In this study, we genotyped two mutations (A376G and G202A), which confer the most common G6PDd variant in West African populations, G6PDd A−. We estimated the frequency of G6PDd A− in a sample of febrile patients enrolled in an on-going malaria study who represent a potential target population for a primaquine mass drug administration. We found that 33 of 168 individuals carried the G6PDd A− allele (includes A− hemizygous males, A− homozygous or heterozygous females) and could experience toxicity if treated with primaquine. These data inform discussions on safe and effective primaquine dosing and future malaria elimination strategies for Haiti. PMID:24891465

Effect of Punica granatum fruit peel on glucose-6-phosphate dehydrogenase and malate dehydrogenase in amphistome Gastrothylax indicus.

Science.gov (United States)

Aggarwal, Rama; Bagai, Upma

2017-03-01

Increasing anthelmintic resistance and the impact of conventional anthelmintics on the environment, it is important to look for alternative strategies against helminth parasite in sheep. Important lipogenic enzymes like glucose-6-phosphate dehydrogenase (G-6-PDH) and malate dehydrogenase (MDH) show subcellular distribution pattern. Activity of G-6-PDH was largely restricted to cytosolic fraction while MDH was found in both cytosolic and mitochondrial fraction in Gastrothylax indicus. Following in vitro treatment with ethanolic and aqueous extracts of Punica granatum fruit peel and commercial anthelmintic, albendazole G-6-PDH activity was decreased by 19-32 %, whereas MDH was suppressed by 24-41 %, compared to the respective control. Albendazole was quite effective when compared with negative control and both the extracts. The results indicate that phytochemicals of plant may act as potential vermifuge or vermicide.

Deficiencia de glucosa 6-fostato deshidrogenasa en hombres sanos y en pacientes maláricos; Turbo (Antioquia, Colombia Deficiency of glucose-6-phosphate dehydrogenase in healthy men and malaria patients; Turbo (Antioquia, Colombia

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Jaime Carmona-Fonseca

2008-06-01

Full Text Available INTRODUCCIÓN: En América Latina la deficiencia de glucosa 6-fosfato deshidrogenasa (d-G6PD ha sido poco estudiada y en Colombia solo conocemos tres publicaciones antiguas. Urge conocer más la prevalencia de d-G6PD, sobre todo ahora que el tratamiento de la malaria vivax plantea aumentar la dosis diaria o total de primaquina. OBJETIVO: Medir la prevalencia de d-G6PD en poblaciones masculina sana y de enfermos con malaria por Plasmodium vivax, en Turbo (Urabá, departamento de Antioquia, Colombia. METODOLOGÍA: Encuestas de prevalencia, para evaluar la G6PD en dos poblaciones de Turbo (Antioquia: hombres sanos; hombres y mujeres con malaria vivax. Se trabajó con muestras diseñadas con criterios estadístico-epidemiológicos. La actividad enzimática se midió con el método normalizado de Beutler para valorar la G6PD en hemolizados. RESULTADOS: Entre los hombres sanos (n = 508, el intervalo de confianza 95% para el promedio (IC95% estuvo entre 4,15 y 4,51 UI/g hemoglobina y 14,8% presentaron valores por debajo del "límite normal" de INTRODUCTION: Glucose-6-phosphate dehydrogenase (G6PD deficiency in Latin America has not been fully studied and in Colombia only three outdated publications are known. Recent information on the prevalence of G6PD deficiency is required now, because the recommended treatment of vivax malaria requires higher daily or total doses of primaquine. OBJECTIVE: To measure the prevalence of G6PD in a healthy male population and in a Plasmodium vivax infected population in Turbo (Urabá, Antioquia Department, Colombia. METHOD: Prevalence survey to evaluate G6PD in two populations of Turbo (Antioquia: healthy male; male and female with vivax malaria. The work was carried out on population samples selected using statistical and epidemiological criteria. Enzyme activity was measured using Beutler's normalized method to evaluate G6PD after hemolysis. RESULTS: For the healthy male group (n = 508, and with a 95% confidence

Two new glucose 6-phosphate dehydrogenase variants associated with congenital nonspherocytic hemolytic anemia found in Japan: GD(-) Tokushima and GD(-) Tokyo.

Science.gov (United States)

Miwa, S; Ono, J; Nakashima, K; Abe, S; Kageoka, T

1976-01-01

Two new variants of glucose 6-phosphate dehydrogenase (G6PD) deficiency associated with chronic nonspherocytic hemolytic anemia were discovered in Japan. Gd(-) Tokushima was found in a 17-years-old male whose erythrocytes contained 4.4% of normal enzyme activity. Partially purified enzyme revealed a main band of normal electrophoretic mobility with additional two minor bands of different mobility; normal Km G6P, and Km NADP five-to sixfold higher than normal; normal utilization of 2-deoxy-G6P, galactose-6P, and deamino-NADP; marked thermal instability; a normal pH curve; and normal Ki NADPH. The hemolytic anemia was moderate to severe. Gd(-) Tokyo was characterized from a 15-year-old male who had chronic nonspherocytic hemolytic anemia of mild degree. The erythrocytes contained 3% of normal enzyme activity, and partially purified enzyme revealed slow electrophoretic mobility (90% of normal for both a tris-hydrochloride buffer system and a tris-EDTA-borate buffer system, and 70% of normal for a phosphate buffer system); normal Km G6P and Km NADP; normal utilization of 2-deoxy-G6P, galactose-6P, and deamino-NADP; greatly increased thermal instability; a normal pH curve; and normal Ki NADPH. These two variants are clearly different from hitherto described G6PD variants, including the Japanese variants Gd(-) Heian and Gd(-) Kyoto. The mothers of both Gd(-) Tokushima and Gd(-) Tokoyo were found to be heterozygote by an ascorbate-cyanide test.

Combined Effect of L-Cysteine and Vitamin E Injected Pre-Irradiation on Glucose-6-Phosphate Dehydrogenase Activity and Certain products of Glycolysis in Blood of Female Rats

International Nuclear Information System (INIS)

Abdel-Fattah, K.I.; Abou-Safi, H.M.; Kafafy, Y.A.; Ashry, O.M.

1999-01-01

The present work aims to evaluate the protective limits of L-cysteine and vitamin E combination against deleterious effects of gamma radiation on glucose-6-phosphate dehydrogenase activity, liver glycogen, blood glucose, pyruvic and lactic acids and their correlations in adult female rats. Mature female white rats were divided into four groups: 1- Control group. 2- Whole body gamma irradiated group at a dose level two Gy. 3-Group injected with 120 mg/100 g b.wt. L-cysteine+10 mg/100 g b.wt. vitamin E. 4- Group injected with cysteine+ vitamin E one hour before irradiation at 2 Gy dose level. Results revealed that combined administration of cysteine and vitamin E before gamma-irradiation have accelerated the radiation injury on liver glycogen, plasma glucose and G 6 Pd activity, while they showed a protective effect on lactic and pyruvic acids. This could be due to different mechanisms or a biphasic mechanism related to hormonal (like E 2 , T 3 and insulin), enzymatic or metabolic (e.g. oxidation/reduction, catabolic, anabolic factors) control

Triiodothyronine (T3)-associated upregulation and downregulation of nuclear T3 binding in the human fibroblast cell (MRC-5)--stimulation of malic enzyme, glucose-6-phosphate-dehydrogenase, and 6-phosphogluconate-dehydrogenase by insulin, but not by T3

DEFF Research Database (Denmark)

Matzen, L E; Kristensen, S R; Kvetny, J

1991-01-01

The specific nuclear binding of triiodothyronine (T3) (NBT3) and the activity of malic enzyme (ME), glucose-6-phosphate-dehydrogenase (G6PD), and 6-phosphogluconate-dehydrogenase (6PGD) were studied in the human fibroblast cell (MRC-5). The overall apparent binding affinity (Ka) was 2.7 x 10(9) L.......mol-1 estimated from kinetic studies of nuclear T3 binding, and 2.5 x 10(9) L.mol-1 estimated from equilibrium studies. The scatchard plots were curvilinear and composed of a high-affinity binding site with Ka1 3.4 +/- 0.7 x 10(9) L.mol-1 and maximal binding capacity (MBC) MBC1 57.0 +/- 11.9 fmol/mg DNA...... and a low-affinity binding site with Ka2 2.9 +/- 1.1 x 10(8) L.mol-1 and MBC2 124.7 +/- 22.1 fmol/mg DNA (n = 6). Incubation of cells with 6 nmol/L T3 for 20 hours reduced NBT3 to 62.2% +/- 15.7% (P less than .01, n = 11). The Ka estimated from kinetic studies was reduced to 6.7 x 10(7) L.mol-1...

Effect of High-Dose Vitamin C Infusion in a Glucose-6-Phosphate Dehydrogenase-Deficient Patient

Science.gov (United States)

Gerber, Bryan; Kenyon, Katharine; Muthukanagaraj, Purushothaman

2017-01-01

Vitamin C supplementation is generally regarded as benign. There has been a resurgence of interest in the general medical community regarding the use of vitamin C most notably in the care of sepsis. Nonetheless, caution must be taken if supraphysiologic vitamin C supplementation is being administered as it should be considered a medication just like any other. We present a case of hemolysis in a glucose-6-phosphate dehydrogenase- (G6PD-) deficient patient receiving high-dose vitamin C infusions for his rheumatoid arthritis. PMID:29317868

Glucose-6-phosphate dehydrogenase deficiency does not increase the susceptibility of sperm to oxidative stress induced by H2O2.

Science.gov (United States)

Roshankhah, Shiva; Rostami-Far, Zahra; Shaveisi-Zadeh, Farhad; Movafagh, Abolfazl; Bakhtiari, Mitra; Shaveisi-Zadeh, Jila

2016-12-01

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzyme defect. G6PD plays a key role in the pentose phosphate pathway, which is a major source of nicotinamide adenine dinucleotide phosphate (NADPH). NADPH provides the reducing equivalents for oxidation-reduction reductions involved in protecting against the toxicity of reactive oxygen species such as H 2 O 2 . We hypothesized that G6PD deficiency may reduce the amount of NADPH in sperms, thereby inhibiting the detoxification of H 2 O 2 , which could potentially affect their motility and viability, resulting in an increased susceptibility to infertility. Semen samples were obtained from four males with G6PD deficiency and eight healthy males as a control. In both groups, motile sperms were isolated from the seminal fluid and incubated with 0, 10, 20, 40, 60, 80, and 120 µM concentrations of H 2 O 2 . After 1 hour incubation at 37℃, sperms were evaluated for motility and viability. Incubation of sperms with 10 and 20 µM H 2 O 2 led to very little decrease in motility and viability, but motility decreased notably in both groups in 40, 60, and 80 µM H 2 O 2 , and viability decreased in both groups in 40, 60, 80, and 120 µM H 2 O 2 . However, no statistically significant differences were found between the G6PD-deficient group and controls. G6PD deficiency does not increase the susceptibility of sperm to oxidative stress induced by H 2 O 2 , and the reducing equivalents necessary for protection against H 2 O 2 are most likely produced by other pathways. Therefore, G6PD deficiency cannot be considered as major risk factor for male infertility.

Prevalence of thalassaemia, iron-deficiency anaemia and glucose-6-phosphate dehydrogenase deficiency among Arab migrating nomad children, southern Islamic Republic of Iran.

Science.gov (United States)

Pasalar, M; Mehrabani, D; Afrasiabi, A; Mehravar, Z; Reyhani, I; Hamidi, R; Karimi, M

2014-12-17

This study investigated the prevalence of iron-deficiency anaemia, glucose-6-phosphate dehydrogenase (G6PD) deficiency and β-thalassaemia trait among Arab migrating nomad children in southern Islamic Republic of Iran. Blood samples were analysed from 134 schoolchildren aged child had G6PD deficiency. A total of 9.7% of children had HbA2 ≥ 3.5 g/dL, indicating β-thalassaemia trait (10.8% in females and 7.8% in males). Mean serum iron, serum ferritin and total iron binding capacity were similar in males and females. Serum ferritin index was as accurate as Hb index in the diagnosis of iron-deficiency anaemia. A high prevalence of β-thalassaemia trait was the major potential risk factor in this population.

Interesting case of G6PD deficiency anemia with severe hemolysis

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Anupam Chhabra

2013-01-01

Full Text Available Severe hemolysis was observed in a critically ill patient with G6Pd deficiency where the causative trigger could not be identified. We describe one young patient with severe hemolysis treated with two cycles of plasmapheresis which proved to be an effective tool in the treatment. The patient presented with diffuse pain abdomen, vomiting, yellowish discoloration of sclera and skin and acute breathlessness. Hemoglobin 5.4 mg/dl and total (T serum bilirubin 17.08 mg/dl: Direct (D 4.10 mg/dl and Indirect (I 12.98 mg/dl. Subsequently patient started passing black color urine. As the patient developed severe hemolysis and the trigger agent of hemolysis was unknown, two cycles of plasmapheresis were performed with the aim to remove unknown causative agent. Consequently no trace of hemolysis was found and patient stabilized. Plasmapheresis can be used to treat G6PD deficient patients with severe hemolysis due to unidentified trigger agent.

Importance of glucose-6-phosphate dehydrogenase (G6PDH) for vanillin tolerance in Saccharomyces cerevisiae.

Science.gov (United States)

Nguyen, Trinh Thi My; Kitajima, Sakihito; Izawa, Shingo

2014-09-01

Vanillin is derived from lignocellulosic biomass and, as one of the major biomass conversion inhibitors, inhibits yeast growth and fermentation. Vanillin was recently shown to induce the mitochondrial fragmentation and formation of mRNP granules such as processing bodies and stress granules in Saccharomyces cerevisiae. Furfural, another major biomass conversion inhibitor, also induces oxidative stress and is reduced in an NAD(P)H-dependent manner to its less toxic alcohol derivative. Therefore, the pentose phosphate pathway (PPP), through which most NADPH is generated, plays a role in tolerance to furfural. Although vanillin also induces oxidative stress and is reduced to vanillyl alcohol in a NADPH-dependent manner, the relationship between vanillin and PPP has not yet been investigated. In the present study, we examined the importance of glucose-6-phosphate dehydrogenase (G6PDH), which catalyzes the rate-limiting NADPH-producing step in PPP, for yeast tolerance to vanillin. The growth of the null mutant of G6PDH gene (zwf1Δ) was delayed in the presence of vanillin, and vanillin was efficiently reduced in the culture of wild-type cells but not in the culture of zwf1Δ cells. Furthermore, zwf1Δ cells easily induced the activation of Yap1, an oxidative stress responsive transcription factor, mitochondrial fragmentation, and P-body formation with the vanillin treatment, which indicated that zwf1Δ cells were more susceptible to vanillin than wild type cells. These findings suggest the importance of G6PDH and PPP in the response of yeast to vanillin. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Association of glucose-6-phosphate dehydrogenase deficiency and X-linked chronic granulomatous disease in a child with anemia and recurrent infections

OpenAIRE

Agudelo-Florez, P.; Costa-Carvalho, Beatriz Tavares [UNIFESP; Lopez, J. A.; Redher, J.; Newburger, P. E.; Alla-Saad, S. T.; Condino-Neto, A.

2004-01-01

Patients with severe leukocyte G6PD deficiency may present with impairment of NADPH oxidase activity and a history of recurrent infections, mimicking the phenotype of chronic granulomatous disease. We report herein a child with recurrent infections who initially received the diagnosis of G6PD deficiency. His erythrocyte G6PD activity was reduced: 1.8 U/g Hb (normal: 12.1 +/- 2.1 U/g Hb). Further studies revealed that G6PD activity in neutrophils, mononuclear leukocytes, and Epstein-Barr virus...

Subcellular Characterization of Porcine Oocytes with Different Glucose-6-phosphate Dehydrogenase Activities

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Bo Fu

2015-12-01

Full Text Available The in vitro maturation (IVM efficiency of porcine embryos is still low because of poor oocyte quality. Although brilliant cresyl blue positive (BCB+ oocytes with low glucose-6-phosphate dehydrogenase (G6PDH activity have shown superior quality than BCB negative (− oocytes with high G6PDH activity, the use of a BCB staining test before IVM is still controversial. This study aimed to shed more light on the subcellular characteristics of porcine oocytes after selection using BCB staining. We assessed germinal vesicle chromatin configuration, cortical granule (CG migration, mitochondrial distribution, the levels of acetylated lysine 9 of histone H3 (AcH3K9 and nuclear apoptosis features to investigate the correlation between G6PDH activity and these developmentally related features. A pattern of chromatin surrounding the nucleoli was seen in 53.0% of BCB+ oocytes and 77.6% of BCB+ oocytes showed peripherally distributed CGs. After IVM, 48.7% of BCB+ oocytes had a diffused mitochondrial distribution pattern. However, there were no significant differences in the levels of AcH3K9 in the nuclei of blastocysts derived from BCB+ and BCB− oocytes; at the same time, we observed a similar incidence of apoptosis in the BCB+ and control groups. Although this study indicated that G6PDH activity in porcine oocytes was correlated with several subcellular characteristics such as germinal vesicle chromatin configuration, CG migration and mitochondrial distribution, other features such as AcH3K9 level and nuclear apoptotic features were not associated with G6PDH activity and did not validate the BCB staining test. In using this test for selecting porcine oocytes, subcellular characteristics such as the AcH3K9 level and apoptotic nuclear features should also be considered. Adding histone deacetylase inhibitors or apoptosis inhibitors into the culture medium used might improve the efficiency of IVM of BCB+ oocytes.

Immune Thrombocytopenia Resolved by Eltrombopag in a Carrier of Glucose-6-Phosphate Dehydrogenase Deficiency

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Laura Scaramucci

2016-03-01

Full Text Available Eltrombopag, a thrombopoietin mimetic peptide, may provide excellent clinical efficacy in steroid-refractory patients with immune thrombocytopenic purpura (ITP [1,2]. Eltrombopag is generally well tolerated. However, its use in the particular setting of glucose-6-phosphate dehydrogenase (G6PD and history of acute hemolytic anemia (AHA has not been reported so far. A 51-year-old female was diagnosed as having ITP in September 2014. She was not taking any medication and her past history was negative, apart from having been diagnosed a carrier (heterozygous of G6PD deficiency (Mediterranean variant after a familial screening by molecular and biochemical methods. She presented with only slightly reduced (about 50% enzyme level, belonging to World Health Organization-defined class 3 [3,4]. In the following years, the patient experienced some episodes of AHA, which were managed at outside institutions; in particular, a severe episode of AHA, probably triggered by urinary infection and antibiotics [5], had complicated her second and last delivery. The hemolytic episodes were selflimiting and resolved without sequelae. No other causes of hemolysis were documented. When the case came to our attention, a diagnosis of ITP was made; hemolytic parameters were normal, although the G6PD enzyme concentration was not measured. Oral prednisone (1 mg/kg was given with only a transient benefit. The patient was then a candidate for elective splenectomy. However, given her extremely low platelet count, she was started in October 2014 on eltrombopag at 50 mg/day as a bridge to splenectomy. Given that, to the best of our knowledge, the use of this drug has never been reported in the particular setting of G6PD deficiency, the patient was constantly monitored. A prompt platelet increase (178x109/L was observed 1 week after the start of treatment. After she achieved the target platelet count, the dose of eltrombopag was tapered to the lowest effective dose. The patient�

Effects of whole body x-ray irradiation on induction by phenobarbital of rat liver glucose-6-phosphate dehydrogenase and glutathione reductase

Energy Technology Data Exchange (ETDEWEB)

Bitny-Szlachto, S.; Szyszko, A. (Wojskowy Inst. Higieny i Epidemiologii, Warsaw (Poland))

1979-01-01

In rats treated with phenobarbital (3x100 mg/kg, i.p.), liver G-6-P dehydrogenase activity increased by 70% in the cytosol and in the 9.000xg supernatant, and only by 20% in microsomes. Moreover, the phenobarbital treatment increased rat liver GSSG reductase activity by 30%. On the other hand, activity of the liver microsomal G-6-P dehydrogenase was found to increase by some 20% in whole body irradiated, both control and phenobarbital treated rats. In rats irradiated with 600 R prior to the first dose of the inducer there was not noted any increase in G-6-P dehydrogenase of the 9.000xg supernatant, and increase in the cytosol activity dropped to 38%. Thus, induction of the soluble liver G-6-P dehydrogenase by phenobarbital has turned out to be radiosensitive, whereas phenobarbital induction of GSSG reductase was unaffected by irradiation.

Kinetic and thermodynamic study of the reaction catalyzed by glucose-6-phosphate dehydrogenase with nicotinamide adenine dinucleotide

International Nuclear Information System (INIS)

Martin del Campo, Julia S.; Patino, Rodrigo

2011-01-01

Research highlights: → The reaction catalyzed by one enzyme of the pentose phosphate pathway was studied. → A spectrophotometric method is proposed for kinetic and thermodynamic analysis. → The pH and the temperature influences are reported on physical chemical properties. → Relative concentrations of substrates are also important in the catalytic process. - Abstract: The enzyme glucose-6-phosphate dehydrogenase (G6PD, EC 1.1.1.49) from Leuconostoc mesenteroides has a dual coenzyme specificity with oxidized nicotinamide adenine dinucleotide (NAD ox ) and oxidized nicotinamide adenine dinucleotide phosphate as electron acceptors. The G6PD coenzyme selection is determined by the metabolic cellular prevailing conditions. In this study a kinetic and thermodynamic analysis is presented for the reaction catalyzed by G6PD from L. mesenteroides with NAD ox as coenzyme in phosphate buffer. For this work, an in situ spectrophotometric technique was employed based on the detection of one product of the reaction. Substrate and coenzyme concentrations as well as temperature and pH effects were evaluated. The apparent equilibrium constant, the Michaelis constant, and the turnover number were determined as a function of each experimental condition. The standard transformed Gibbs energy of reaction was determined from equilibrium constants at different initial conditions. For the product 6-phospho-D-glucono-1,5-lactone, a value of the standard Gibbs energy of formation is proposed, Δ f G o = -1784 ± 5 kJ mol -1 .

Kinetic and thermodynamic study of the reaction catalyzed by glucose-6-phosphate dehydrogenase with nicotinamide adenine dinucleotide

Energy Technology Data Exchange (ETDEWEB)

Martin del Campo, Julia S. [Departamento de Fisica Aplicada, Centro de Investigacion y de Estudios Avanzados - Unidad Merida, Carretera antigua a Progreso Km. 6, A.P. 73 Cordemex, 97310, Merida, Yucatan (Mexico); Patino, Rodrigo, E-mail: rtarkus@mda.cinvestav.mx [Departamento de Fisica Aplicada, Centro de Investigacion y de Estudios Avanzados - Unidad Merida, Carretera antigua a Progreso Km. 6, A.P. 73 Cordemex, 97310, Merida, Yucatan (Mexico)

2011-04-20

Research highlights: {yields} The reaction catalyzed by one enzyme of the pentose phosphate pathway was studied. {yields} A spectrophotometric method is proposed for kinetic and thermodynamic analysis. {yields} The pH and the temperature influences are reported on physical chemical properties. {yields} Relative concentrations of substrates are also important in the catalytic process. - Abstract: The enzyme glucose-6-phosphate dehydrogenase (G6PD, EC 1.1.1.49) from Leuconostoc mesenteroides has a dual coenzyme specificity with oxidized nicotinamide adenine dinucleotide (NAD{sub ox}) and oxidized nicotinamide adenine dinucleotide phosphate as electron acceptors. The G6PD coenzyme selection is determined by the metabolic cellular prevailing conditions. In this study a kinetic and thermodynamic analysis is presented for the reaction catalyzed by G6PD from L. mesenteroides with NAD{sub ox} as coenzyme in phosphate buffer. For this work, an in situ spectrophotometric technique was employed based on the detection of one product of the reaction. Substrate and coenzyme concentrations as well as temperature and pH effects were evaluated. The apparent equilibrium constant, the Michaelis constant, and the turnover number were determined as a function of each experimental condition. The standard transformed Gibbs energy of reaction was determined from equilibrium constants at different initial conditions. For the product 6-phospho-D-glucono-1,5-lactone, a value of the standard Gibbs energy of formation is proposed, {Delta}{sub f}G{sup o} = -1784 {+-} 5 kJ mol{sup -1}.

INFLUENCE OF SELECTED PHARMACEUTICALS ON ACTIVATED SLUDGE DEHYDROGENASE ACTIVITY

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Agnieszka Tomska

2016-06-01

The aim of this work was to evaluate the effect of selected antibiotics - sulfanilamide and erythromycin on activated sludge dehydrogenase activity with use of trifenyltetrazolinum chloride (TTC test. Dehydrogenases activity is an indicator of biochemical activity of microorganisms present in activated sludge or the ability to degrade organic compounds in waste water. TTC test is particularly useful for the regularity of the course of treatment, in which the presence of inhibitors of biochemical reactions and toxic compounds are present. It was observed that the dehydrogenase activity decreases with the increase of a antibiotics concentration. The lowest value of the dehydrogenase activity equal to 32.4 μmol TF / gMLSS obtained at sulfanilamide concentration 150mg / l. For this sample, an inhibition of dehydrogenase activity was 31%.

Prevalence of anemia, iron deficiency, thalassemia and glucose-6-phosphate dehydrogenase deficiency among hill-tribe school children in Omkoi District, Chiang Mai Province, Thailand.

Science.gov (United States)

Yanola, Jintana; Kongpan, Chatpat; Pornprasert, Sakorn

2014-07-01

The prevalaence of anemia, iron deficiency, thalassemia and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency were examined among 265 hill-tribe school children, 8-14 years of age, from Omkoi District, Chiang Mai Province, Thailand. Anemia was observed in 20 school children, of whom 3 had iron deficiency anemia. The prevalence of G-6-PD deficiency and β-thalassemia trait [codon 17 (A>T), IVSI-nt1 (G>T) and codons 71/72 (+A) mutations] was 4% and 8%, respectively. There was one Hb E trait, and no α-thalassemia-1 SEA or Thai type deletion. Furthermore, anemia was found to be associated with β-thalassemia trait in 11 children. These data can be useful for providing appropriate prevention and control of anemia in this region of Thailand.

The Effects of Fenarimol and Methyl Parathion on Glucose 6-Phosphate Dehydrogenase Enzyme Activity in Rats

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Ferda ARI

2017-10-01

Full Text Available Fenarimol and methyl parathion are pesticides that have been used in agriculture for several years. These pesticides have significant effects on environmental and human health. Therefore, we investigated the effects of methyl parathion and fenarimol on glucose 6-phosphate dehydrogenase (EC 1.1.1.49 enzyme activity in rats. The glucose 6- phosphate dehydrogenase is the first enzyme of the pentose phosphate pathway and it is important in detoxifying reactions by NADPH generated. In this study, wistar albino rats administrated with methyl parathion (7 mg kg–1 and fenarimol (200 mg kg−1 by intraperitoneally for different periods (2, 4, 8, 16, 32, 64, and 72 h. The glucose 6-phosphate dehydrogenase enzyme activity was assayed in liver, kidney, brain, and small intestine in male and female rats. The exposure of fenarimol and methyl parathion caused increase of glucose 6-phosphate dehydrogenase enzyme activity in rat tissues, especially at last periods. We suggest that this increment of enzyme activity may be the reason of toxic effects of fenarimol and methyl parathion.

Oral supplementation of vitamin E reduces osmotic fragility of RBC in hemolytic anemic patients with G6PD deficiency

International Nuclear Information System (INIS)

Sultana, N.; Begum, S.; Begum, N.; Ali, T.

2009-01-01

Vitamin E has role in maintaining the integrity of red cell member by preventing oxidation of polyunsaturated fatty acids, thus protects cells from oxidative stress-induced lysis in G6PD deficiency. Changes in osmotic fragility of RBC and some absolute values like MCV, MCH and MCHC may occur in haemolytic anaemic patients with G6PD deficiency. To observe the effects of vitamin E supplementation on these changes in order to evaluate the role of this anti-oxidant vitamin in reducing chronic haemolysis in G6PD deficient patients. A total number of 102 subjects with age ranged of 5 to 40 years of both sexes were included in the study. Among them 68 were G6PD enzyme deficient patients, of whom 34 were in supplemented group (experimental group) and 34 were in non-supplemented group (control group). The supplemented group received vitamin E supplementation for 60 consecutive days at a dose of 800 IU/day for adult and 400 IU/day for children ?12 years (in a divided dose, i.e., 4 times daily). Age and sex matched 34 apparently healthy subjects with normal blood G6PD level were taken to observe the base line data (healthy control) and also for comparison. All the G6PD deficient patients were selected from Out Patient Department (OPD) of Haematology, Banglabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from July 2005 to June 2006 and all healthy subjects were selected from personal contact. Blood G6PD level, osmotic fragility of RBC were measured by standard techniques and MCV, MCH, and MCHC were obtained by calculation. All the parameters were measured on day 1 of their first visit and also were on day 60 in deficient group. Data were compared among the deficient groups, also in supplemented group just before and after supplementation. Analysis of data was done by appropriate statistical method. Mean starting and completing points of osmotic fragility of RBC were significantly higher but MCV. MCH, MCHC were significantly lower in patients suffering from

Comparison of Three Screening Test Kits for G6PD Enzyme Deficiency: Implications for Its Use in the Radical Cure of Vivax Malaria in Remote and Resource-Poor Areas in the Philippines.

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Fe Esperanza Espino

Full Text Available We evaluated a battery of Glucose-6-Phosphate Dehydrogenase diagnostic point-of-care tests (PoC to assess the most suitable product in terms of performance and operational characteristics for remote areas.Samples were collected in Puerto Princesa City, Palawan, Philippines and tested for G6PD deficiency with a fluorescent spot test (FST; Procedure 203, Trinity Biotech, Ireland, the semiquantitative WST8/1-methoxy PMS (WST; Dojindo, Japan and the Carestart G6PD Rapid Diagnostic Test (CSG; AccessBio, USA. Results were compared to spectrophotometry (Procedure 345, Trinity Biotech, Ireland. Sensitivity and specificity were calculated for each test with cut-off activities of 10%, 20%, 30% and 60% of the adjusted male median.The adjusted male median was 270.5 IU/10(12 RBC. FST and WST were tested on 621 capillary blood samples, the CSG was tested on venous and capillary blood on 302 samples. At 30% G6PD activity, sensitivity for the FST was between 87.7% (95%CI: 76.8% to 93.9% and 96.5% (95%CI: 87.9% to 99.5% depending on definition of intermediate results; the WST was 84.2% (95%CI: 72.1% to 92.5%; and the CSG was between 68.8% (95%CI: 41.3% to 89.0% and 93.8% (95%CI: 69.8% to 99.8% when the test was performed on capillary or venous blood respectively. Sensitivity of FST and CSG (tested with venous blood were comparable (p>0.05. The analysis of venous blood samples by the CSG yielded significantly higher results than FST and CSG performed on capillary blood (p<0.05. Sensitivity of the CSG varied depending on source of blood used (p<0.05.The operational characteristics of the CSG were superior to all other test formats. Performance and operational characteristics of the CSG performed on venous blood suggest the test to be a good alternative to the FST.

Hexose-6-phosphate dehydrogenase contributes to skeletal muscle homeostasis independent of 11β-hydroxysteroid dehydrogenase type 1.

LENUS (Irish Health Repository)

Semjonous, Nina M

2011-01-01

Glucose-6-phosphate (G6P) metabolism by the enzyme hexose-6-phosphate dehydrogenase (H6PDH) within the sarcoplasmic reticulum lumen generates nicotinamide adenine dinucleotide phosphate (reduced) to provide the redox potential for the enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) to activate glucocorticoid (GC). H6PDH knockout (KO) mice have a switch in 11β-HSD1 activity, resulting in GC inactivation and hypothalamic-pituitary-adrenal axis activation. Importantly, H6PDHKO mice develop a type II fiber myopathy with abnormalities in glucose metabolism and activation of the unfolded protein response (UPR). GCs play important roles in muscle physiology, and therefore, we have examined the importance of 11β-HSD1 and GC metabolism in mediating aspects of the H6PDHKO myopathy. To achieve this, we examined 11β-HSD1\\/H6PDH double-KO (DKO) mice, in which 11β-HSD1 mediated GC inactivation is negated. In contrast to H6PDHKO mice, DKO mice GC metabolism and hypothalamic-pituitary-adrenal axis set point is similar to that observed in 11β-HSD1KO mice. Critically, in contrast to 11β-HSD1KO mice, DKO mice phenocopy the salient features of the H6PDHKO, displaying reduced body mass, muscle atrophy, and vacuolation of type II fiber-rich muscle, fasting hypoglycemia, increased muscle glycogen deposition, and elevated expression of UPR genes. We propose that muscle G6P metabolism through H6PDH may be as important as changes in the redox environment when considering the mechanism underlying the activation of the UPR and the ensuing myopathy in H6PDHKO and DKO mice. These data are consistent with an 11β-HSD1-independent function for H6PDH in which sarcoplasmic reticulum G6P metabolism and nicotinamide adenine dinucleotide phosphate-(oxidized)\\/nicotinamide adenine dinucleotide phosphate (reduced) redox status are important for maintaining muscle homeostasis.

LDH and G-6PDH activities in the ovaries of adult female Wistar rats ...

African Journals Online (AJOL)

The present study was designed to evaluate the effects of aqueous extracts of neem (Azadirachta Indica) leaves (which have been documented for its antifertility effect on experimental animals) on glucose-6-phosphate dehydrogenase (G-6PDH) and lactate dehydrogenase (LDH) levels in the ovaries of adult female wistar ...

Glucose-6-phosphate dehydrogenase deficiency in people living in malaria endemic districts of Nepal.

Science.gov (United States)

Ghimire, Prakash; Singh, Nihal; Ortega, Leonard; Rijal, Komal Raj; Adhikari, Bipin; Thakur, Garib Das; Marasini, Baburam

2017-05-23

Glucose-6-phosphate dehydrogenase (G6PD) is a rate limiting enzyme of the pentose phosphate pathway and is closely associated with the haemolytic disorders among patients receiving anti-malarial drugs, such as primaquine. G6PD deficiency (G6PDd) is an impending factor for radical treatment of malaria which affects the clearance of gametocytes from the blood and subsequent delay in the achievement of malaria elimination. The main objective of this study was to assess the prevalence of G6PD deficiency in six malaria endemic districts in Southern Nepal. A cross-sectional population based prevalence survey was conducted in six malaria endemic districts of Nepal, during April-Dec 2013. A total of 1341 blood samples were tested for G6PDd using two different rapid diagnostic test kits (Binax-Now ® and Care Start™). Equal proportions of participants from each district (n ≥ 200) were enrolled considering ethnic and demographic representation of the population groups. Out of total 1341 blood specimens collected from six districts, the overall prevalence of G6PDd was 97/1341; 7.23% on Binax Now and 81/1341; 6.0% on Care Start test. Higher prevalence was observed in male than females [Binax Now: male 10.2%; 53/521 versus female 5.4%; 44/820 (p = 0.003) and Care Start: male 8.4%; 44/521 versus female 4.5%; 37/820 (p = 0.003)]. G6PDd was higher in ethnic groups Rajbanshi (11.7%; 19/162) and Tharu (5.6%; 56/1005) (p = 0.006), major inhabitant of the endemic districts. Higher prevalence of G6PDd was found in Jhapa (22/224; 9.8%) and Morang districts (18/225; 8%) (p = 0.031). In a multivariate analysis, male were found at more risk for G6PDd than females, on Binax test (aOR = 1.97; CI 1.28-3.03; p = 0.002) and Care Start test (aOR = 1.86; CI 1.16-2.97; p = 0.009). The higher prevalence of G6PDd in certain ethnic group, gender and geographical region clearly demonstrates clustering of the cases and ascertained the risk groups within the population. This is the

Prevalence of Sickle Cell Trait and Glucose 6 Phosphate ...

African Journals Online (AJOL)

Blood donation from sickle cell trait (SCT) and glucose-6-phosphate dehydrogenase (G6PD)-deficient donors might alter the quality of the donated blood during processing, storage or in the recipients' circulatory system. The aim of this study was to determine the prevalence of SCT and G6PD deficiency among blood ...

A role for AMPK in the inhibition of glucose-6-phosphate dehydrogenase by polyunsaturated fatty acids

Energy Technology Data Exchange (ETDEWEB)

Kohan, Alison B.; Talukdar, Indrani; Walsh, Callee M. [Department of Biochemistry, West Virginia University, Morgantown, WV (United States); Salati, Lisa M., E-mail: lsalati@hsc.wvu.edu [Department of Biochemistry, West Virginia University, Morgantown, WV (United States)

2009-10-09

Both polyunsaturated fatty acids and AMPK promote energy partitioning away from energy consuming processes, such as fatty acid synthesis, towards energy generating processes, such as {beta}-oxidation. In this report, we demonstrate that arachidonic acid activates AMPK in primary rat hepatocytes, and that this effect is p38 MAPK-dependent. Activation of AMPK mimics the inhibition by arachidonic acid of the insulin-mediated induction of G6PD. Similar to intracellular signaling by arachidonic acid, AMPK decreases insulin signal transduction, increasing Ser{sup 307} phosphorylation of IRS-1 and a subsequent decrease in AKT phosphorylation. Overexpression of dominant-negative AMPK abolishes the effect of arachidonic acid on G6PD expression. These data suggest a role for AMPK in the inhibition of G6PD by polyunsaturated fatty acids.

Glucose-6-phosphate dehydrogenase deficiency and the risk of malaria: A meta-analysis and trial sequential analysis

Science.gov (United States)

Sun, Fengmei; Zhang, Juan; Pu, Yuepu

2017-10-01

This study is designed to perform a meta-analysis and trial sequential analysis (TSA) to investigate whether people with G6PD deficiency suffered less malarial infection. We searched from PubMed, Science Direct, Springer Link, CNKI, and Wan Fang databases for case-control study, cohort study or cross section study until April 2017. TSA was used to determine the state of evidence and calculate the required sample size. Eight case-control studies and five cross-sectional studies (30,683participants) were included in this meta-analysis. Compared with normal control group, we found significant protection from severe malaria (OR 0.644, 95% CI [0.493-0.842]; P=0.001) among people with decreasing G6PD activity. People with variations of G6PD gene at nucleotide 202(G6PD A-) were also found to be associated with resistance on severe malaria pooled (OR 0.851, 95% CI [0.779-0.930]; P =0.0001). Sex-stratified test suggested that protection of severe malaria is conferred to both G6PD A-males and heterozygous females (with a single copy of the variant). In conclusion, our study found a significant protection from severe malaria among G6PD deficient people compared to the

Predicting the Kinetic Properties Associated with Redox Imbalance after Oxidative Crisis in G6PD-Deficient Erythrocytes: A Simulation Study

Directory of Open Access Journals (Sweden)

Hanae Shimo

2011-01-01

Full Text Available It is well known that G6PD-deficient individuals are highly susceptible to oxidative stress. However, the differences in the degree of metabolic alterations among patients during an oxidative crisis have not been extensively studied. In this study, we applied mathematical modeling to assess the metabolic changes in erythrocytes of various G6PD-deficient patients during hydrogen peroxide- (H2O2- induced perturbation and predict the kinetic properties that elicit redox imbalance after exposure to an oxidative agent. Simulation results showed a discrepancy in the ability to restore regular metabolite levels and redox homeostasis among patients. Two trends were observed in the response of redox status (GSH/GSSG to oxidative stress, a mild decrease associated with slow recovery and a drastic decline associated with rapid recovery. The former was concluded to apply to patients with severe clinical symptoms. Low max and high mG6P of G6PD were shown to be kinetic properties that enhance consequent redox imbalance.

Rapid diagnostic test for G6PD deficiency in Plasmodium vivax-infected men: a budget impact analysis based in Brazilian Amazon.

Science.gov (United States)

Peixoto, Henry Maia; Brito, Marcelo Augusto Mota; Romero, Gustavo Adolfo Sierra; Monteiro, Wuelton Marcelo; de Lacerda, Marcus Vinícius Guimarães; de Oliveira, Maria Regina Fernandes

2017-01-01

The aim of this study was to estimate the incremental budget impact (IBI) of a rapid diagnostic test to detect G6PDd in male patients infected with Plasmodium vivax in the Brazilian Amazon, as compared with the routine protocol recommended in Brazil which does not include G6PDd testing. The budget impact analysis was performed from the perspective of the Brazilian health system, in the Brazilian Amazon for the years 2013, 2014 and 2015. The analysis used a decision model to compare two scenarios: the first consisting of the routine recommended in Brazil which does not include prior diagnosis of dG6PD, and the second based on the use of RDT CareStart™ G6PD (CS-G6PD) in all male subjects diagnosed with vivax malaria. The expected implementation of the diagnostic test was 30% in the first year, 70% the second year and 100% in the third year. The analysis identified negative IBIs which were progressively smaller in the 3 years evaluated. The sensitivity analysis showed that the uncertainties associated with the analytical model did not significantly affect the results. A strategy based on the use of CS-G6PD would result in better use of public resources in the Brazilian Amazon. © 2016 John Wiley & Sons Ltd.

Triagem neonatal de deficiência de glicose-6-fosfato desidrogenase e prevalência das mutações G202A (G6PD A-) e C563T (G6PD Mediterrâneo) em Mato Grosso/Brasil

OpenAIRE

Maria de Fatima de Carvalho Ferreira

2014-01-01

Objetivos: A deficiência de glicose-6-fosfato desidrogenase (G6PD) está associada a um maior risco de encefalopatia bilirrubínica e de crise hemolítica aguda grave desencadeada por drogas como a primaquina e a dapsona. Conhecer a prevalência dessa deficiência enzimática em área onde a malária e a hanseníase ainda estão presentes e conhecer a prevalência das principais mutações traz subsídios para planejamento de estratégias com vistas à redução de riscos associados a esta deficiência enzimáti...

High-fat diet enhanced retinal dehydrogenase activity, but suppressed retinol dehydrogenase activity in liver of rats

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Mian Zhang

2015-04-01

Full Text Available Evidence has shown that hyperlipidemia is associated with retinoid dyshomeostasis. In liver, retinol is mainly oxidized to retinal by retinol dehydrogenases (RDHs and alcohol dehydrogenases (ADHs, further converted to retinoic acid by retinal dehydrogenases (RALDHs. The aim of this study was to investigate whether high-fat diet (HFD induced hyperlipidemia affected activity and expression of hepatic ADHs/RDHs and RALDHs in rats. Results showed that retinol levels in liver, kidney and adipose tissue of HFD rats were significantly increased, while plasma retinol and hepatic retinal levels were markedly decreased. HFD rats exhibited significantly downregulated hepatic ADHs/RDHs activity and Adh1, Rdh10 and Dhrs9 expression. Oppositely, hepatic RALDHs activity and Raldh1 expression were upregulated in HFD rats. In HepG2 cells, treatment of HFD rat serum inhibited ADHs/RDHs activity and induced RALDHs activity. Among the tested abnormally altered components in HFD rat serum, cholesterol reduced ADHs/RDHs activity and RDH10 expression, while induced RALDHs activity and RALDH1 expression in HepG2 cells. Contrary to the effect of cholesterol, cholesterol-lowering agent pravastatin upregulated ADHs/RDHs activity and RDH10 expression, while suppressed RALDHs activity and RALDH1 expression. In conclusion, hyperlipidemia oppositely altered activity and expression of hepatic ADHs/RDHs and RALDHs, which is partially due to the elevated cholesterol levels.

Glucose-6-phosphate mediates activation of the carbohydrate responsive binding protein (ChREBP)

International Nuclear Information System (INIS)

Li, Ming V.; Chen, Weiqin; Harmancey, Romain N.; Nuotio-Antar, Alli M.; Imamura, Minako; Saha, Pradip; Taegtmeyer, Heinrich; Chan, Lawrence

2010-01-01

Carbohydrate response element binding protein (ChREBP) is a Mondo family transcription factor that activates a number of glycolytic and lipogenic genes in response to glucose stimulation. We have previously reported that high glucose can activate the transcriptional activity of ChREBP independent of the protein phosphatase 2A (PP2A)-mediated increase in nuclear entry and DNA binding. Here, we found that formation of glucose-6-phosphate (G-6-P) is essential for glucose activation of ChREBP. The glucose response of GAL4-ChREBP is attenuated by D-mannoheptulose, a potent hexokinase inhibitor, as well as over-expression of glucose-6-phosphatase (G6Pase); kinetics of activation of GAL4-ChREBP can be modified by exogenously expressed GCK. Further metabolism of G-6-P through the two major glucose metabolic pathways, glycolysis and pentose-phosphate pathway, is not required for activation of ChREBP; over-expression of glucose-6-phosphate dehydrogenase (G6PD) diminishes, whereas RNAi knockdown of the enzyme enhances, the glucose response of GAL4-ChREBP, respectively. Moreover, the glucose analogue 2-deoxyglucose (2-DG), which is phosphorylated by hexokinase, but not further metabolized, effectively upregulates the transcription activity of ChREBP. In addition, over-expression of phosphofructokinase (PFK) 1 and 2, synergistically diminishes the glucose response of GAL4-ChREBP. These multiple lines of evidence support the conclusion that G-6-P mediates the activation of ChREBP.

Glucose-6-Phosphate Dehydrogenase Deficiency and Haemoglobin Drop after Sulphadoxine-Pyrimethamine Use for Intermittent Preventive Treatment of Malaria during Pregnancy in Ghana - A Cohort Study.

Directory of Open Access Journals (Sweden)

Ruth Owusu

Full Text Available Sulphadoxine-Pyrimethamine (SP is still the only recommended antimalarial for use in intermittent preventive treatment of malaria during pregnancy (IPTp in some malaria endemic countries including Ghana. SP has the potential to cause acute haemolysis in G6PD deficient people resulting in significant haemoglobin (Hb drop but there is limited data on post SP-IPTp Hb drop. This study determined the difference, if any in proportions of women with significant acute haemoglobin drop between G6PD normal, partial deficient and full deficient women after SP-IPTp.Prospectively, 1518 pregnant women who received SP for IPTp as part of their normal antenatal care were enrolled. Their G6PD status were determined at enrollment followed by assessments on days 3, 7,14 and 28 to document any adverse effects and changes in post-IPTp haemoglobin (Hb levels. The three groups were comparable at baseline except for their mean Hb (10.3 g/dL for G6PD normal, 10.8 g/dL for G6PD partial deficient and 10.8 g/dL for G6PD full defect women.The prevalence of G6PD full defect was 2.3% and 17.0% for G6PD partial defect. There was no difference in the proportions with fractional Hb drop ≥ 20% as compared to their baseline value post SP-IPTp among the 3 groups on days 3, 7, 14. The G6PD full defect group had the highest median fractional drop at day 7. There was a weak negative correlation between G6PD activity and fractional Hb drop. There was no statistical difference between the three groups in the proportions of those who started the study with Hb ≥ 8g/dl whose Hb level subsequently fell below 8g/dl post-SP IPTp. No study participant required transfusion or hospitalization for severe anaemia.There was no significant difference between G6PD normal and deficient women in proportions with significant acute haemoglobin drop post SP-IPTp and lower G6PD enzyme activity was not strongly associated with significant acute drug-induced haemoglobin drop post SP-IPTp but a larger

Erythrocyte glucose-6-phosphate dehydrogenase deficiency in male newborn babies and its relationship with neonatal jaundice Deficiência de glicose-6-fosfato desidrogenase eritrocitária em recém-nascidos do sexo masculino e sua relação com a icterícia neonatal

Directory of Open Access Journals (Sweden)

Marli Auxiliadora C. Iglessias

2010-01-01

Full Text Available Glucose-6-phosphate dehydrogenase (G6PD deficiency, the commonest red cell enzymopathy in humans, has an X-linked inheritance. The major clinical manifestations are drug induced hemolytic anemia, neonatal jaundice and chronic nonspherocytic hemolytic anemia. The incidence of neonatal hyperbilirubinemia is much greater in G6PD-deficient neonates than babies without this deficiency. The aim of this study was to ascertain the presence of neonatal jaundice in erythrocyte G6PD-deficient male newborns. Samples of umbilical cord blood from a total of 204 male newborns of the Januário Cicco School Maternity located in Natal, Rio Grande do Norte, Brazil were analyzed. The G6PD deficiency was identified by the methemoglobin reduction test (Brewer's test. The deficiency was confirmed by quantitative spectrophotometric assay for enzyme activity and cellulose acetate electrophoresis was used to identify the G6PD variant. Eight newborns were found to be G6PD deficient with four of them exhibiting jaundice during the first 48 hours after birth with bilirubin levels higher than 10 mg/dL. All deficient individuals presented the G6PD A- variant at electrophoresis. Our findings confirmed the association between G6PD deficiency and neonatal jaundice. Hence, early diagnosis of the deficiency at birth is essential to control the appearance of jaundice and to prevent the exposure of these newborns to known hemolytic agents.A deficiência de glicose-6-fosfato desidrogenase (G6PD é a anormalidade enzimática hereditária mais frequente. É transmitida como caráter recessivo ligado ao cromossomo X e as principais manifestações clínicas são hemólise induzida por fármacos, icterícia neonatal e anemia hemolítica não esferocítica. O objetivo do estudo foi determinar a presença de icterícia neonatal em recém-nascidos do sexo masculino deficientes de glicose-6-fosfato desidrogenase. Foram analisadas 204 amostras de sangue umbilical de recém-nascidos do sexo

Prevalence of glucose-6-phosphate dehydrogenase deficiency in ...

African Journals Online (AJOL)

Pradeep Kumar

2016-02-06

Feb 6, 2016 ... Hemolytic anemia; ... G6PD deficiency is the commonest hemolytic X-linked genetic disease, which affects .... tain drugs or infection, can elicit acute hemolysis. ..... down syndrome risk: a meta-analysis from 34 studies.

Cytosolic NADP(+)-dependent isocitrate dehydrogenase status modulates oxidative damage to cells.

Science.gov (United States)

Lee, Su Min; Koh, Ho-Jin; Park, Dong-Chan; Song, Byoung J; Huh, Tae-Lin; Park, Jeen-Woo

2002-06-01

NADPH is an important cofactor in many biosynthesis pathways and the regeneration of reduced glutathione, critically important in cellular defense against oxidative damage. It is mainly produced by glucose 6-phosphate dehydrogenase (G6PD), malic enzyme, and the cytosolic form of NADP(+)-dependent isocitrate dehydrogenase (IDPc). Little information is available about the role of IDPc in antioxidant defense. In this study we investigated the role of IDPc against cytotoxicity induced by oxidative stress by comparing the relative degree of cellular responses in three different NIH3T3 cells with stable transfection with the cDNA for mouse IDPc in sense and antisense orientations, where IDPc activities were 3-4-fold higher and 35% lower, respectively, than that in the parental cells carrying the vector alone. Although the activities of other antioxidant enzymes, such as superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase, and G6PD, were comparable in all transformed cells, the ratio of GSSG to total glutathione was significantly higher in the cells expressing the lower level of IDPc. This finding indicates that IDPc is essential for the efficient glutathione recycling. Upon transient exposure to increasing concentrations of H(2)O(2) or menadione, an intracellular source of free radicals and reactive oxygen species, the cells with low levels of IDPc became more sensitive to oxidative damage by H(2)O(2) or menadione. Lipid peroxidation, oxidative DNA damage, and intracellular peroxide generation were higher in the cell-line expressing the lower level of IDPc. However, the cells with the highly over-expressed IDPc exhibited enhanced resistance against oxidative stress, compared to the control cells. This study provides direct evidence correlating the activities of IDPc and the maintenance of the cellular redox state, suggesting that IDPc plays an important role in cellular defense against oxidative stress.

Glucose-6-phosphate dehydrogenase protects Escherichia coli from tellurite-mediated oxidative stress.

Directory of Open Access Journals (Sweden)

Juan M Sandoval

Full Text Available The tellurium oxyanion tellurite induces oxidative stress in most microorganisms. In Escherichia coli, tellurite exposure results in high levels of oxidized proteins and membrane lipid peroxides, inactivation of oxidation-sensitive enzymes and reduced glutathione content. In this work, we show that tellurite-exposed E. coli exhibits transcriptional activation of the zwf gene, encoding glucose 6-phosphate dehydrogenase (G6PDH, which in turn results in augmented synthesis of reduced nicotinamide adenine dinucleotide phosphate (NADPH. Increased zwf transcription under tellurite stress results mainly from reactive oxygen species (ROS generation and not from a depletion of cellular glutathione. In addition, the observed increase of G6PDH activity was paralleled by accumulation of glucose-6-phosphate (G6P, suggesting a metabolic flux shift toward the pentose phosphate shunt. Upon zwf overexpression, bacterial cells also show increased levels of antioxidant molecules (NADPH, GSH, better-protected oxidation-sensitive enzymes and decreased amounts of oxidized proteins and membrane lipids. These results suggest that by increasing NADPH content, G6PDH plays an important role in E. coli survival under tellurite stress.

Hierarchical Bi{sub 2}WO{sub 6} architectures decorated with Pd nanoparticles for enhanced visible-light-driven photocatalytic activities

Energy Technology Data Exchange (ETDEWEB)

Zhang, Jinniu; Chen, Tianhua [School of Physics and Information Technology, Shaanxi Normal University, Xi’an, 710062 (China); Lu, Hongbing, E-mail: hblu@snnu.edu.cn [School of Physics and Information Technology, Shaanxi Normal University, Xi’an, 710062 (China); Yang, Zhibo; Yin, Feng; Gao, Jianzhi; Liu, Qianru [School of Physics and Information Technology, Shaanxi Normal University, Xi’an, 710062 (China); Tu, Yafang [Department of Physics, Institute for Interdisciplinary Research, Jianghan University, Wuhan, 430056 (China)

2017-05-15

Highlights: • A new kind of Pd decorated Bi{sub 2}WO{sub 6} hierarchical microarchitecture was synthesized. • Pd nanoparticles remarkably improved the photocatalytic activity of Bi{sub 2}WO{sub 6}. • The photo-generated holes and ·O{sub 2}{sup −} played a crucial role in the degradation of RhB. • The photocatalytic enhancement mechanism of the Pd-Bi{sub 2}WO{sub 6} composites was proposed. - Abstract: A new kind of hierarchical Pd-Bi{sub 2}WO{sub 6} architecture decorated with different molar ratios of Pd to Bi, has been fabricated by a hydrothermal process, followed by a chemical deposition method. The photocatalytic activities of the pure Bi{sub 2}WO{sub 6} and Pd-Bi{sub 2}WO{sub 6} nanocatalyst were examined in the degradation of Rhodamine B (RhB) dyes and phenol under visible light. The photocatalytic results showed that the Pd-Bi{sub 2}WO{sub 6} nanocomposites possessed observably enhanced photocatalytic activities. Particularly, the 2.0% Pd loaded Bi{sub 2}WO{sub 6} had the highest photocatalytic activity, exhibiting a nearly complete degradation of 30 mg/L RhB and 10 mg/L phenol within only 50 and 60 min, respectively. In addition, the trapping experiment results indicated that the photo-generated holes (h{sup +}) and ·O{sub 2}{sup −} played a crucial role in the degradation of RhB. According to the experimental results, the photocatalytic degradation mechanism of Pd-Bi{sub 2}WO{sub 6} was also proposed. The enhanced photocatalytic activities were ascribed to the combined effects of the highly efficient separation of electrons and holes, improved visible light utilization and increased BET specific surface areas of the Pd-Bi{sub 2}WO{sub 6} nanocomposites.

EFFECTS OF PARTIAL HEPATECTOMY, PHENOBARBITAL AND 3-METHYLCHOLANTHRENE ON KINETIC-PARAMETERS OF GLUCOSE-6-PHOSPHATE AND PHOSPHOGLUCONATE DEHYDROGENASE IN-SITU IN PERIPORTAL, INTERMEDIATE AND PERICENTRAL ZONES OF RAT-LIVER LOBULES

NARCIS (Netherlands)

Jonges, G. N.; Vogels, I. M. C.; van Noorden, C. J. F.

1995-01-01

Glucose-6-phosphate dehydrogenase (G6PDH) and phosphogluconate dehydrogenase (PGDH) are heterogeneously distributed in liver lobules of female rats. The maximum activity of both enzymes is approximately twice higher in intermediate and pericentral zones than in periportal zones. Enzyme activities

Prevalence of glucose-6-phosphate dehydrogenase deficiency and ...

African Journals Online (AJOL)

. ... while statistical analysis was done using STATA soft- ware version 8 (STATA Corp., College station, TX). Prevalence of G6PD and HbAS in bivariate variables ... Multivariate logis- .... technique (Enevold et al., 2007) found prevalence of.

Glucose 6-phosphate dehydrogenase deficiency and cystic fibrosis

OpenAIRE

Congdon, P. J.; Aggarwal, R. K.; Littlewood, J. M.; Shapiro, H.

1981-01-01

A child born to Pakistani parents is described. He had both cystic fibrosis and G-6PD-deficiency. So far as can be ascertained, the occurrence of both these conditions in the same individual has not previously been reported.

Cytophotometry of glucose-6-phosphate dehydrogenase activity in individual cells

NARCIS (Netherlands)

van Noorden, C. J.; Tas, J.; Vogels, I. M.

1983-01-01

With the aid of thin films of polyacrylamide gel containing purified glucose-6-phosphate dehydrogenase subjected to cytochemical procedures for the enzyme using tetranitro blue tetrazolium, arbitrary units of integrated absorbance obtained with a Barr & Stroud GN5 cytophotometer were converted into

Effects of IL-6 on pyruvate dehydrogenase regulation in mouse skeletal muscle

DEFF Research Database (Denmark)

Biensø, Rasmus Sjørup; Knudsen, Jakob Grunnet; Brandt, Nina

2014-01-01

Skeletal muscle regulates substrate choice according to demand and availability and pyruvate dehydrogenase (PDH) is central in this regulation. Circulating interleukin (IL)-6 increases during exercise and IL-6 has been suggested to increase whole body fat oxidation. Furthermore, IL-6 has been...... reported to increase AMP-activated protein kinase (AMPK) phosphorylation and AMPK suggested to regulate PDHa activity. Together, this suggests that IL-6 may be involved in regulating PDH. The aim of this study was to investigate the effect of a single injection of IL-6 on PDH regulation in skeletal muscle...... in fed and fasted mice. Fed and 16-18 h fasted mice were injected with either 3 ng · g(-1) recombinant mouse IL-6 or PBS as control. Fasting markedly reduced plasma glucose, muscle glycogen, muscle PDHa activity, as well as increased PDK4 mRNA and protein content in skeletal muscle. IL-6 injection did...

Deficiencia de glucosa-6-fosfato deshidrogenasa en un paciente con síndrome de Down

Directory of Open Access Journals (Sweden)

Francisco R. Cammarata Scalisi

2012-07-01

Full Text Available El síndrome de Down, es una alteración genética que ocurre cuando un individuo exhibe todo o una parte específica adicional del cromosoma 21 y es la entidad más frecuentemente asociada a retardo mental. La deficiencia de glucosa-6-fosfato deshidrogenasa, es el defecto enzimático más común en humanos y presenta patrón de herencia ligado al cromosoma X recesivo. Se debe a la mutación del gen G6PD, el cual causa diversos fenotipos bioquímicos y clínicos. Reportamos un caso de lactante menor masculino, evaluado en la Unidad de Genética Médica de la Universidad de Los Andes, con el diagnóstico de deficiencia de glucosa-6-fosfato deshidrogenasa con doble mutación A376G y G202A y síndrome de Down con estudio citogenético 47, XY, +21. Palabras clave:Síndrome de Down; deficiencia de glucosa-6-fosfato deshidrogenasa; G6PD; A37G6; G202A. Glucose-6-phosphate dehydrogenase deficiency in a patient with Down syndrome Abstract Down syndrome, is a genetic disorder that occurring when an individual exhibits all or part of an extra copy of chromosome 21 and the most common entity associated mental retardation. Glucose-6-phosphate dehydrogenase deficiency, is the most common human enzyme defect and has a X-linked recessive inheritance. Due to mutations in the G6PD gene, which cause many biochemical and clinical phenotypes. We reported a case of child male, evaluated in the Unit of Medical Genetics of the University of The Andes, with diagnosis of glucose-6-phosphate dehydrogenase deficiency with double mutation A376G and G202A and Down syndrome with cytogenetic study 47, XY, + 21.

Physiological role of glucose-6-phosphate dehydrogenase in cold acclimation of strawberry (Fragaria × ananassa)

Science.gov (United States)

Zhang, Yong; Yu, Dingqun; Luo, Ya; Wang, Xiaorong; Chen, Qing; Sun, Bo; Wang, Yan; Liu, Zejing; Tang, Haoru

2018-04-01

In recent years, there has been an increasing interest in study of new resistance mechanism in fruit trees. All these regard the climate change and subsequent fruit production. Glucose-6-phosphate dehydrogenase (G6PDH) catalyzes the first and rate-limiting step of the oxidative pentose phosphate pathway (OPPP), and the expression of this enzyme is related to different biotic and abiotic stresses. Under accumulation of low temperature stress, the significant increase in G6PDH activity was found to be closely correlated to the levels of antioxidant enzymes, malondialdehyde (MDA) contents, sugar contents as well as changes of superoxide (O2•-). It is suggested that the enhancement of cold resistance of strawberry, which induced by cold acclimation, related to the significant increase in G6PDH activity. On one hand, G6PDH activates NADPH oxidase to generate reactive oxygen species (ROS); on the other hand, it may be involved in the activation of antioxidant enzymes, and accelerates many other important NADPH-dependent enzymatic reactions. Then further result in the elevation of membrane stability and cold resistance of strawberry. Interestingly, even though the plants were placed again under a temperature of 25°C for 1 d, the higher cold resistance, enzyme activities and soluble sugar content acquired.

Glucose-6-phosphate dehydrogenase deficiency in northern Mexico ...

Indian Academy of Sciences (India)

screening, in which the haplotype analysis was performed. Group B .... Thr65 in the native structure of human G6PD, the same protein .... this mutation has a very low frequency in the Mexican popu- lation, we can predict a significant health impact in the males .... genase deficiency: a systematic review and meta-analysis.

Quantitative aspects of the cytochemical demonstration of glucose-6-phosphate dehydrogenase with tetranitro BT studied in a model system of polyacrylamide films

NARCIS (Netherlands)

van Noorden, C. J.; Tas, J.

1980-01-01

The cytochemical determination of the activity of glucose-6-phosphate dehydrogenase (G6PDH) with tetranitro blue tetrazolium (TNBT) was studied with model films of polyacrylamide gel incorporating purified enzyme. This model system enabled a quantitative study to be made of different parameters

Neonatal screening for sickle cell disease, Glucose-6-PhosphateDehydrogenase deficiency and Alpha-Thalassemia in Qatif and Al-Hasa

International Nuclear Information System (INIS)

Nasserullah, Z.; Srair, Hussain Abu; Al-Jame, A.; Mokhtar, M.; Al-Qatari, G.; Al-Naim, S.; Al-Aqib, A.

1998-01-01

Screening programs to determine the frequency of sickle cell,glucose-6-phosphate dehydrogenase deficiency and alpha-thalassemia gene areavailable in Saudi Arabia, although not used frequently. Greater use of theseprograms will decrease the morbidity and mortality of Saudi children affectedby these disorders. Neonatal hemoglobin electrophoresis andglucose-6-dehydrogenase fluorescent spot tests were performed on new bornbabies delivered between December 1992 and December 1993 at the Qatif CentralHospital and at the King Fahd Hospital in Al-Hasa. Cord blood samples werecollected from babies born in these two hospitals. Babies born in otherhospitals had blood collected in their first visit to Qatif primary carecenters at the time of vaccination. All specimens were sent to Dammam CentralLaboratory. The diagnosis of sickle cell and alpha-thalassemia was based oncellulose acetate electrophoresis and confirmed by agar gel electrophoresisand glucose-6-phosphate dehydrgenase was confirmed by fluorescent spot test.A total of 12,220 infants, including 11,313 Saudis (92.6%), were screenedover a 12-month period. The common phenotype detected in these infantsincluded AF, SFA, SFA Bart's, FS and FS Bart's. In Saudi infants, homozygoussickle cell disease was detected in 2.35% and 1.08% in Qatif and Al-Hasa,respectively. The frequencies of sickle cell gene were 0.1545% and 0.1109% inQatif and Al-Hasa. Alpha-thalassemia genes based on an elevated level of HbBart's were 28% and 16.3% in Qatif and Al-Hasa. The screening for G6PDdeficiency revealed a high prevalence of 30.6% and 14.7% in Qatif andAl-Hasa. In the non-Saudi infants the frequencies were low. The outcome ofthis study indicates that the Saudi populations in Qatif and Al-Hasa are atrisk for hemoglobinopathies and G6PD. Neonatal screening programs areessential and cost effective and should be maintained as a routine practice.(author)

Quantitative cytochemical analysis of glucose-6-phosphate dehydrogenase activity in living isolated hepatocytes of European flounder for rapid analysis of xenobiotic effects

NARCIS (Netherlands)

Winzer, K.; van Noorden, C. J.; Köhler, A.

2001-01-01

There is a great need for rapid but reliable assays to determine quantitatively effects of xenobiotics on biological systems in environmental research. Hepatocytes of European flounder are sensitive to low-dose toxic stress. Glucose-6-phosphate dehydrogenase (G6PDH) is the major source of NADPH in

Hyperbilirubinaemia and erythrocytic glucose 6 phosphate dehydrogenase deficiency in Malaysian children.

Science.gov (United States)

Hon, A T; Balakrishnan, S; Ahmad, Z

1989-03-01

Cord blood from 8,975 babies delivered in Hospital Sultanah Aminah Johor Bahru over a period of eight months (1st August 1985 to 31st March 1986) were screened for G6PD deficiency. The overall incidence was 4.5% in Chinese, 3.5% in Malays and 1.5% in Indian babies. One hundred of these babies were observed in the nursery for seven days and their daily serum bilirubin recorded. The serum bilirubin peaked at 96 hours to a value of 12mg%. None of the babies in the nursery developed a serum bilirubin level of more than 15mg%. Six of the babies with G6PD deficiency that were sent home were readmitted with hyperbilirubinaemia that needed exchange transfusion.

Reaction rate studies of glucose-6-phosphate dehydrogenase activity in sections of rat liver using four tetrazolium salts

NARCIS (Netherlands)

Butcher, R. G.; van Noorden, C. J.

1985-01-01

The reaction rate of glucose-6-phosphate dehydrogenase activity in liver sections from fed and starved rats has been monitored by the continuous measurement at 37 degrees C of the reaction product as it is formed using scanning and integrating microdensitometry. Control media lacked either substrate

Mechanism of NO Photocatalytic Oxidationon g-C3N4 Was Changed by Pd-QDs Modification

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Yuhan Li

2015-12-01

Full Text Available Quantum dot (QD sensitization can increase the light absorption and electronic transmission of photocatalysts. However, limited studies have been conducted on the photocatalytic activity of photocatalysts after modification by noble metal QDs. In this study, we developed a simple method for fabricating Pd-QD-modified g-C3N4. Results showed that the modification of Pd-QDs can improve the NO photocatalytic oxidation activity of g-C3N4. Moreover, Pd-QD modification changed the NO oxidation mechanism from the synergistic action of h+ and O2− to the single action of ·OH. We found that the main reason for the mechanism change was that Pd-QD modification changed the molecular oxygen activation pathway from single-electron reduction to two-electron reduction. This study can not only develop a novel strategy for modifying Pd-QDs on the surface of photocatalysts, but also provides insight into the relationship between Pd-QD modification and the NO photocatalytic oxidation activity of semiconductor photocatalysts.

A highly efficient sorbitol dehydrogenase from Gluconobacter oxydans G624 and improvement of its stability through immobilization.

Science.gov (United States)

Kim, Tae-Su; Patel, Sanjay K S; Selvaraj, Chandrabose; Jung, Woo-Suk; Pan, Cheol-Ho; Kang, Yun Chan; Lee, Jung-Kul

2016-09-16

A sorbitol dehydrogenase (GoSLDH) from Gluconobacter oxydans G624 (G. oxydans G624) was expressed in Escherichia coli BL21(DE3)-CodonPlus RIL. The complete 1455-bp codon-optimized gene was amplified, expressed, and thoroughly characterized for the first time. GoSLDH exhibited Km and kcat values of 38.9 mM and 3820 s(-1) toward L-sorbitol, respectively. The enzyme exhibited high preference for NADP(+) (vs. only 2.5% relative activity with NAD(+)). GoSLDH sequencing, structure analyses, and biochemical studies, suggested that it belongs to the NADP(+)-dependent polyol-specific long-chain sorbitol dehydrogenase family. GoSLDH is the first fully characterized SLDH to date, and it is distinguished from other L-sorbose-producing enzymes by its high activity and substrate specificity. Isothermal titration calorimetry showed that the protein binds more strongly to D-sorbitol than other L-sorbose-producing enzymes, and substrate docking analysis confirmed a higher turnover rate. The high oxidation potential of GoSLDH for D-sorbitol was confirmed by cyclovoltametric analysis. Further, stability of GoSLDH significantly improved (up to 13.6-fold) after cross-linking of immobilized enzyme on silica nanoparticles and retained 62.8% residual activity after 10 cycles of reuse. Therefore, immobilized GoSLDH may be useful for L-sorbose production from D-sorbitol.

G6PD deficiency and absence of α-thalassemia increase the risk for cerebral vasculopathy in children with sickle cell anemia.

Science.gov (United States)

Joly, Philippe; Garnier, Nathalie; Kebaili, Kamila; Renoux, Céline; Dony, Arthur; Cheikh, Nathalie; Renard, Cécile; Ceraulo, Antony; Cuzzubbo, Daniela; Pondarré, Corinne; Martin, Cyril; Pialoux, Vincent; Francina, Alain; Bertrand, Yves; Connes, Philippe

2016-04-01

The aim of this study was to test the association between hematological/genetic factors and cerebral vasculopathy in children with sickle cell anemia (SCA). A group with cerebral vasculopathy (VASC) was composed of children who had stroke (n = 6), silent infarct (n = 11), or an abnormal transcranial Doppler (n = 5). Eighty-four patients had neither positive history of stroke or silent infarct, nor abnormal transcranial Doppler (NORM group). An intermediate group (COND; n = 15) was composed of SCA children with a conditional transcranial Doppler. Biological analyses were performed on samples obtained at steady state and before the beginning of any chronic treatment. The comparisons of the three groups demonstrated a protective effect of α-thalassemia against cerebral vasculopathy through its effects on hemoglobin and reticulocyte levels. Moreover, we observed higher frequency of G6PD deficiency in the VASC group compared with the other groups. Our study confirms the key role of α-thalassemia and G6PD status in the pathophysiology of cerebral vasculopathy in SCA children. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Biochemical characteristics of glucose-6-phosphate dehydrogenase variants among the Malays of Singapore with report of a new non-deficient (GdSingapore) and three deficient variants.

Science.gov (United States)

Saha, N; Hong, S H; Wong, H A; Jeyaseelan, K; Tay, J S

1991-12-01

Biochemical characteristics of one non-deficient fast G6PD variant (GdSingapore) and six different deficient variants (three new, two Mahidol, one each of Indonesian and Mediterranean) were studied among the Malays of Singapore. The GdSingapore variant had normal enzyme activity (82%) and fast electrophoretic mobilities (140% in TEB buffer, 160% in phosphate and 140% in Tris-HCl buffer systems respectively). This variant is further characterized by normal Km for G6P; utilization of analogues (Gal6P, 2dG6P; dAmNADP), heat stability and pH optimum. The other six deficient G6PD variants had normal electrophoretic mobility in TEB buffer with enzyme activities ranging from 1 to 12% of GdB+. The biochemical characteristics identity them to be 2 Mahidol, 1 Indonesian and 1 Mediterranean variants and three new deficient variants.

Improved ethanol electrooxidation performance by shortening Pd-Ni active site distance in Pd-Ni-P nanocatalysts

Science.gov (United States)

Chen, Lin; Lu, Lilin; Zhu, Hengli; Chen, Yueguang; Huang, Yu; Li, Yadong; Wang, Leyu

2017-01-01

Incorporating oxophilic metals into noble metal-based catalysts represents an emerging strategy to improve the catalytic performance of electrocatalysts in fuel cells. However, effects of the distance between the noble metal and oxophilic metal active sites on the catalytic performance have rarely been investigated. Herein, we report on ultrasmall (~5 nm) Pd-Ni-P ternary nanoparticles for ethanol electrooxidation. The activity is improved up to 4.95 A per mgPd, which is 6.88 times higher than commercial Pd/C (0.72 A per mgPd), by shortening the distance between Pd and Ni active sites, achieved through shape transformation from Pd/Ni-P heterodimers into Pd-Ni-P nanoparticles and tuning the Ni/Pd atomic ratio to 1:1. Density functional theory calculations reveal that the improved activity and stability stems from the promoted production of free OH radicals (on Ni active sites) which facilitate the oxidative removal of carbonaceous poison and combination with CH3CO radicals on adjacent Pd active sites.

Soil dehydrogenase activity of natural macro aggregates in a toposequence of forest soil

Directory of Open Access Journals (Sweden)

Maira Kussainova

2013-01-01

Full Text Available The main objective of this study was to determine changes in soil dehydrogenase activity in natural macro aggregates development along a slope in forest soils. This study was carried out in Kocadag, Samsun, Turkey. Four landscape positions i.e., summit, shoulder backslope and footslope, were selected. For each landseape position, soil macro aggregates were separated into six aggregate size classes using a dry sieving method and then dehydrogenase activity was analyzed. In this research, topography influenced the macroaggregate size and dehydrogenase activity within the aggregates. At all landscape positions, the contents of macro aggregates (especially > 6.3 mm and 2.00–4.75 mm in all soil samples were higher than other macro aggregate contents. In footslope position, the soils had generally the higher dehydrogenase activity than the other positions at all landscape positions. In all positions, except for shoulder, dehydrogenase activity was greater macro aggregates of <1 mm than in the other macro aggregate size.

Screening of Glucose-6-Phosphate Dehydrogenase Deficiency in Cord Blood

Directory of Open Access Journals (Sweden)

Can Acipayam

2014-02-01

Aim: Glucose-6-phosphate dehydrogenase deficiency is an important factor in etiology of pathologic neonatal jaundice. The aim of this study was to indicate the significance of screening glucose-6-phosphate dehydrogenase deficiency in the cord blood of neonates and the frequency of this deficiency in the etiology of neonatal hyperbilirubinemia. Material and Method: The study was performed consecutive 1015 neonates were included. Five hundred fifty six (54.8% of them were male and 459 (45.2% were female. The following parameters were recorded: Gender, birth weight, birth height, head circumference and gestational age. The glucose-6-phosphate dehydrogenase level of neonates were measured with quantitative method in cord blood. Also, hemoglobine, hematocrite, red blood cell count and blood group were measured. The following parameters were recorded in cases with jaundice: exchange transfusion, phototherapy, physiologic and pathologic jaundice, peak bilirubin day, maximum bilirubin level, total bilirubin level at the first day of jaundice, beginning time of jaundice. Results: Enzyme deficiency was detected in 133 (13.1% of neonates and 76 (57% of them were male, 57 (43% were female. Significant difference was detected in low glucose-6-phosphate dehydrogenase enzyme level with jaundice group for total bilirubin level at the first day of jaundice, maximum total bilirubin level and pathologic jaundice (p<0.05. Discussion: The ratio of glucose-6-phosphate dehydrogenase deficiency was found in Edirne in this study and this ratio was higher than other studies conducted in our country. For this reason, glucose-6-phosphate dehydrogenase enzyme level in cord blood of neonates should be measured routinely and high risk neonates should be followed up for hyperbilirubinemia and parents should be informed in our region.

Birth control necessary to limit family size in tribal couples with aberrant heterosis of G-6-PD deficiency and sickle cell disorders in India: an urgency of creating awareness and imparting genetic counseling.

Science.gov (United States)

Balgir, R S

2010-06-01

(i) To study the outcome of ignorance and lack of awareness about sickle cell disease and G-6-PD deficiency among Dhelki Kharia tribal families of Orissa, and (ii) to study the reproductive output in relation to clinical genetics and patho-physiological implications. A random genetic study of screening for hemoglobinopathies and G-6-PD deficiency among Dhelki Kharia tribal community in Sundargarh district of Orissa was carried out for intervention during the year 2000-2004. A total of 81 Dhelki Kharia families were screened and six families with double heterozygosity for above genetic anomalies were encountered. About 2-3 ml. intravenous blood samples were collected in EDTA by disposable syringes and needles after taking informed consent from each individual in the presence of a doctor and community leaders and sent to laboratory at Bhubaneswar for hematological investigations. Analysis was carried out following the standard procedures after cross checking for quality control. There were 12 (about 52%) children out of 23 who were either suffering from sickle cell trait or disease in concurrence with G-6-PD deficiency in hemizygous/heterozygous/homozygous condition in Dhelki Kharia tribal community of Orissa. There were on an average 3.83 number of surviving (range 2-6) children per mother in families of G-6-PD deficiency and sickle cell disorders. The average number of children (3.83) born (range 2-6 children) per mother to carrier/affected mother was much higher than the average for India (2.73). It is very difficult to maintain the normal health of an affected child with aberrant anomalies due to exorbitant cost of treatment, frequent transfusions and huge involvement of economy. One of the implications of aberrant heterosis is its adverse affects on routine individual physiology and hard activities. It is suggested to limit the family size in carrier couples to avoid aberrant heterosis of hereditary hemolytic disorders in their offsprings.

Functional Analysis of Mouse G6pc1 Mutations Using a Novel In Situ Assay for Glucose-6-Phosphatase Activity and the Effect of Mutations in Conserved Human G6PC1/G6PC2 Amino Acids on G6PC2 Protein Expression.

Directory of Open Access Journals (Sweden)

Kayla A Boortz

Full Text Available Elevated fasting blood glucose (FBG has been associated with increased risk for development of type 2 diabetes. Single nucleotide polymorphisms (SNPs in G6PC2 are the most important common determinants of variations in FBG in humans. Studies using G6pc2 knockout mice suggest that G6pc2 regulates the glucose sensitivity of insulin secretion. G6PC2 and the related G6PC1 and G6PC3 genes encode glucose-6-phosphatase catalytic subunits. This study describes a functional analysis of 22 non-synonymous G6PC2 SNPs, that alter amino acids that are conserved in human G6PC1, mouse G6pc1 and mouse G6pc2, with the goal of identifying variants that potentially affect G6PC2 activity/expression. Published data suggest strong conservation of catalytically important amino acids between all four proteins and the related G6PC3 isoform. Because human G6PC2 has very low glucose-6-phosphatase activity we used an indirect approach, examining the effect of these SNPs on mouse G6pc1 activity. Using a novel in situ functional assay for glucose-6-phosphatase activity we demonstrate that the amino acid changes associated with the human G6PC2 rs144254880 (Arg79Gln, rs149663725 (Gly114Arg and rs2232326 (Ser324Pro SNPs reduce mouse G6pc1 enzyme activity without affecting protein expression. The Arg79Gln variant alters an amino acid mutation of which, in G6PC1, has previously been shown to cause glycogen storage disease type 1a. We also demonstrate that the rs368382511 (Gly8Glu, rs138726309 (His177Tyr, rs2232323 (Tyr207Ser rs374055555 (Arg293Trp, rs2232326 (Ser324Pro, rs137857125 (Pro313Leu and rs2232327 (Pro340Leu SNPs confer decreased G6PC2 protein expression. In summary, these studies identify multiple G6PC2 variants that have the potential to be associated with altered FBG in humans.

Common mutations in G6PD of Vietnamese-Kinh deficient patients

African Journals Online (AJOL)

DANG THI LAN ANH

2013-03-20

Mar 20, 2013 ... (2009) found out six mutations in Kinh and Stieng's ethnics population by ... 6. P. D e n z y m e a c tiv ity. (IU. /g. Hb. ) Figure 1. Distribution of patients within the enzyme activity level. step lysis method. This method was improved from method of. Chaimosit ... sent to Sigma Aldrich- Singapore for synthesis.

Photocatalytic C-H Activation and Oxidative Esterification Using Pd@g-C3N4

Data.gov (United States)

U.S. Environmental Protection Agency — Graphitic carbon nitride supported palladium nanoparticles, Pd@g-C3N4, have been synthesized and utilized for the direct oxidative esterification of alcohols using...

Study on the triphenyl tetrazolium chloride– dehydrogenase activity ...

African Journals Online (AJOL)

A quick analysis of the sludge activity method based on triphenyltetrazolium chloride-dehydrogenase activity (TTC-DHA) was developed to change the rule and status of the biological activity of the activated sludge in tomato paste wastewater treatment. The results indicate that dehydrogenase activity (DHA) can effectively ...

AglM and VNG1048G, Two Haloarchaeal UDP-Glucose Dehydrogenases, Show Different Salt-Related Behaviors

OpenAIRE

Kandiba, Lina; Eichler, Jerry

2016-01-01

Haloferax volcanii AglM and Halobacterium salinarum VNG1048G are UDP-glucose dehydrogenases involved in N-glycosylation in each species. Despite sharing >60% sequence identity and the ability of VNG1048G to functionally replace AglM in vivo, these proteins behaved differently as salinity changed. Whereas AglM was active in 2–4 M NaCl, VNG1048G lost much of its activity when salinity dropped below 3 M NaCl. To understand the molecular basis of this phenomenon, each protein was examined by s...

High glucose impairs superoxide production from isolated blood neutrophils

DEFF Research Database (Denmark)

Perner, A; Nielsen, S E; Rask-Madsen, J

2003-01-01

Superoxide (O(2)(-)), a key antimicrobial agent in phagocytes, is produced by the activity of NADPH oxidase. High glucose concentrations may, however, impair the production of O(2)(-) through inhibition of glucose-6-phosphate dehydrogenase (G6PD), which catalyzes the formation of NADPH. This study...... measured the acute effects of high glucose or the G6PD inhibitor dehydroepiandrosterone (DHEA) on the production of O(2)(-) from isolated human neutrophils....

15-hydroxyprostaglandin dehydrogenase activity in vitro in lung and kidney of essential fatty acid-deficient rats

DEFF Research Database (Denmark)

Hansen, Harald S.; Toft, B.S.

1978-01-01

Weanling rats were fed for 6 months on a diet deficient in essential fatty acids: either fat-free, or with 28% (w/w) partially hydrogenated fish oil. Control rats were fed a diet with 28% (w/w) arachis oil for 6 months. 15-Hydroxyprostaglandin dehydrogenase activity was determined as initial rates...... of the two groups on diets deficient in essential fatty acids as compared to the control group. No difference was observed in dehydrogenase activity in the kidneys. The dehydrogenase may be of importance for the regulation of the level of endogenous prostaglandins and, thus, a decrease in activity could...

Purification and characterization of xylitol dehydrogenase with l-arabitol dehydrogenase activity from the newly isolated pentose-fermenting yeast Meyerozyma caribbica 5XY2.

Science.gov (United States)

Sukpipat, Wiphat; Komeda, Hidenobu; Prasertsan, Poonsuk; Asano, Yasuhisa

2017-01-01

Meyerozyma caribbica strain 5XY2, which was isolated from an alcohol fermentation starter in Thailand, was found to catabolize l-arabinose as well as d-glucose and d-xylose. The highest production amounts of ethanol from d-glucose, xylitol from d-xylose, and l-arabitol from l-arabinose were 0.45 g/g d-glucose, 0.60 g/g d-xylose, and 0.61 g/g l-arabinose with 21.7 g/L ethanol, 20.2 g/L xylitol, and 30.3 g/l l-arabitol, respectively. The enzyme with l-arabitol dehydrogenase (LAD) activity was purified from the strain and found to exhibit broad specificity to polyols, such as xylitol, d-sorbitol, ribitol, and l-arabitol. Xylitol was the preferred substrate with K m =16.1 mM and k cat /K m =67.0 min -1 mM -1 , while l-arabitol was also a substrate for the enzyme with K m =31.1 mM and k cat /K m =6.5 min -1  mM -1 . Therefore, this enzyme from M. caribbica was named xylitol dehydrogenase (McXDH). McXDH had an optimum temperature and pH at 40°C and 9.5, respectively. The McXDH gene included a coding sequence of 1086 bp encoding a putative 362 amino acid protein of 39 kDa with an apparent homopentamer structure. Native McXDH and recombinant McXDH exhibited relative activities toward l-arabitol of approximately 20% that toward xylitol, suggesting the applicability of this enzyme with the functions of XDH and LAD to the development of pentose-fermenting Saccharomyces cerevisiae. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Post-irradiation repairing processes of glucose-6-phosphate dehydrogenase and catalase from Hansenula Polymorpha yeast

International Nuclear Information System (INIS)

Postolache, Carmen; Postolache, Cristian; Dinu, Diana; Dinischiotu, Anca; Sahini, Victor Emanuel

2002-01-01

The post-irradiation repairing mechanisms of two Hansenula Polymorpha yeast enzymes, glucose-6-phosphate dehydrogenase and catalase, were studied. The kinetic parameters of the selected enzymes were investigated over one month since the moment of γ-irradiation with different doses in the presence of oxygen. Dose dependent decrease of initial reaction rates was noticed for both enzymes. Small variation of initial reaction rate was recorded for glucose-6-phosphate dehydrogenase over one month, with a decreasing tendency. No significant electrophoretic changes of molecular forms of this enzyme were observed after irradiation. Continuous strong decrease of catalase activity was evident for the first 20 days after irradiation. Partial recovery process of the catalytic activity was revealed by this study. (authors)

Correlation of viral RNA biosynthesis with glucose-6-phosphate dehydrogenase activity and host resistance

Czech Academy of Sciences Publication Activity Database

Šindelář, Luděk; Šindelářová, Milada

2002-01-01

Roč. 215, - (2002), s. 862-869 ISSN 0032-0935 R&D Projects: GA ČR GA522/99/1264 Institutional research plan: CEZ:AV0Z5038910 Keywords : Glucose 6 phosphate dehydrogenase * Nicotiana (viral infection) * Plant viruses Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.960, year: 2002

Structures of the G81A mutant form of the active chimera of (S)-mandelate dehydrogenase and its complex with two of its substrates

Energy Technology Data Exchange (ETDEWEB)

Sukumar, Narayanasami [NE-CAT and Department of Chemistry and Chemical Biology, Cornell University, Building 436E, Argonne National Laboratory, Argonne, IL 60439 (United States); Dewanti, Asteriani [Department of Chemistry and Physics, Western Carolina University, Cullowhee, NC 28723 (United States); Merli, Angelo; Rossi, Gian Luigi [Department of Biochemistry and Molecular Biology, University of Parma, Parma (Italy); Mitra, Bharati [Department of Biochemistry and Molecular Biology, School of Medicine, Wayne State University, Detroit, MI 48201 (United States); Mathews, F. Scott, E-mail: mathews@biochem.wustl.edu [Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St Louis, MO 63110 (United States); NE-CAT and Department of Chemistry and Chemical Biology, Cornell University, Building 436E, Argonne National Laboratory, Argonne, IL 60439 (United States)

2009-06-01

The crystal structure of the G81A mutant form of the chimera of (S)-mandelate dehydrogenase and of its complexes with two of its substrates reveal productive and non-productive modes of binding for the catalytic reaction. The structure also indicates the role of G81A in lowering the redox potential of the flavin co-factor leading to an ∼200-fold slower catalytic rate of substrate oxidation. (S)-Mandelate dehydrogenase (MDH) from Pseudomonas putida, a membrane-associated flavoenzyme, catalyzes the oxidation of (S)-mandelate to benzoylformate. Previously, the structure of a catalytically similar chimera, MDH-GOX2, rendered soluble by the replacement of its membrane-binding segment with the corresponding segment of glycolate oxidase (GOX), was determined and found to be highly similar to that of GOX except within the substituted segments. Subsequent attempts to cocrystallize MDH-GOX2 with substrate proved unsuccessful. However, the G81A mutants of MDH and of MDH-GOX2 displayed ∼100-fold lower reactivity with substrate and a modestly higher reactivity towards molecular oxygen. In order to understand the effect of the mutation and to identify the mode of substrate binding in MDH-GOX2, a crystallographic investigation of the G81A mutant of the MDH-GOX2 enzyme was initiated. The structures of ligand-free G81A mutant MDH-GOX2 and of its complexes with the substrates 2-hydroxyoctanoate and 2-hydroxy-3-indolelactate were determined at 1.6, 2.5 and 2.2 Å resolution, respectively. In the ligand-free G81A mutant protein, a sulfate anion previously found at the active site is displaced by the alanine side chain introduced by the mutation. 2-Hydroxyoctanoate binds in an apparently productive mode for subsequent reaction, while 2-hydroxy-3-indolelactate is bound to the enzyme in an apparently unproductive mode. The results of this investigation suggest that a lowering of the polarity of the flavin environment resulting from the displacement of nearby water molecules caused by

An investigation of the mimetic enzyme activity of two-dimensional Pd-based nanostructures

Science.gov (United States)

Wei, Jingping; Chen, Xiaolan; Shi, Saige; Mo, Shiguang; Zheng, Nanfeng

2015-11-01

In this work, we investigated the mimetic enzyme activity of two-dimensional (2D) Pd-based nanostructures (e.g. Pd nanosheets, Pd@Au and Pd@Pt nanoplates) and found that they possess intrinsic peroxidase-, oxidase- and catalase-like activities. These nanostructures were able to activate hydrogen peroxide or dissolved oxygen for catalyzing the oxidation of organic substrates, and decompose hydrogen peroxide to generate oxygen. More systematic investigations revealed that the peroxidase-like activities of these Pd-based nanomaterials were highly structure- and composition-dependent. Among them, Pd@Pt nanoplates displayed the highest peroxidase-like activity. Based on these findings, Pd-based nanostructures were applied for the colorimetric detection of H2O2 and glucose, and also the electro-catalytic reduction of H2O2. This work offers a promising prospect for the application of 2D noble metal nanostructures in biocatalysis.In this work, we investigated the mimetic enzyme activity of two-dimensional (2D) Pd-based nanostructures (e.g. Pd nanosheets, Pd@Au and Pd@Pt nanoplates) and found that they possess intrinsic peroxidase-, oxidase- and catalase-like activities. These nanostructures were able to activate hydrogen peroxide or dissolved oxygen for catalyzing the oxidation of organic substrates, and decompose hydrogen peroxide to generate oxygen. More systematic investigations revealed that the peroxidase-like activities of these Pd-based nanomaterials were highly structure- and composition-dependent. Among them, Pd@Pt nanoplates displayed the highest peroxidase-like activity. Based on these findings, Pd-based nanostructures were applied for the colorimetric detection of H2O2 and glucose, and also the electro-catalytic reduction of H2O2. This work offers a promising prospect for the application of 2D noble metal nanostructures in biocatalysis. Electronic supplementary information (ESI) available: TEM images, EDX and dispersion stability of Pd-based nanomaterials

Highly active Pd-In/mesoporous alumina catalyst for nitrate reduction.

Science.gov (United States)

Gao, Zhenwei; Zhang, Yonggang; Li, Deyi; Werth, Charles J; Zhang, Yalei; Zhou, Xuefei

2015-04-09

The catalytic reduction of nitrate is a promising technology for groundwater purification because it transforms nitrate into nitrogen and water. Recent studies have mainly focused on new catalysts with higher activities for the reduction of nitrate. Consequently, metal nanoparticles supported on mesoporous metal oxides have become a major research direction. However, the complex surface chemistry and porous structures of mesoporous metal oxides lead to a non-uniform distribution of metal nanoparticles, thereby resulting in a low catalytic efficiency. In this paper, a method for synthesizing the sustainable nitrate reduction catalyst Pd-In/Al2O3 with a dimensional structure is introduced. The TEM results indicated that Pd and In nanoparticles could efficiently disperse into the mesopores of the alumina. At room temperature in CO2-buffered water and under continuous H2 as the electron donor, the synthesized material (4.9 wt% Pd) was the most active at a Pd-In ratio of 4, with a first-order rate constant (k(obs) = 0.241 L min(-1) g(cata)(-1)) that was 1.3× higher than that of conventional Pd-In/Al2O3 (5 wt% Pd; 0.19 L min(-1) g(cata)(-1)). The Pd-In/mesoporous alumina is a promising catalyst for improving the catalytic reduction of nitrate. Copyright © 2015 Elsevier B.V. All rights reserved.

Process Integration for the Disruption of Candida guilliermondii Cultivated in Rice Straw Hydrolysate and Recovery of Glucose-6-Phosphate Dehydrogenase by Aqueous Two-Phase Systems.

Science.gov (United States)

Gurpilhares, Daniela B; Pessoa, Adalberto; Roberto, Inês C

2015-07-01

Remaining cells of Candida guilliermondii cultivated in hemicellulose-based fermentation medium were used as intracellular protein source. Recovery of glucose-6-phosphate dehydrogenase (G6PD) was attained in conventional aqueous two-phase systems (ATPS) was compared with integrated process involving mechanical disruption of cells followed by ATPS. Influences of polyethylene glycol molar mass (M PEG) and tie line lengths (TLL) on purification factor (PF), yields in top (Y T ) and bottom (Y B ) phases and partition coefficient (K) were evaluated. First scheme resulted in 65.9 % enzyme yield and PF of 2.16 in salt-enriched phase with clarified homogenate (M PEG 1500 g mol(-1), TLL 40 %); Y B of 75.2 % and PF B of 2.9 with unclarified homogenate (M PEG 1000 g mol(-1), TLL 35 %). The highest PF value of integrated process was 2.26 in bottom phase (M PEG 1500 g mol(-1), TLL 40 %). In order to optimize this response, a quadratic model was predicted for the response PFB for process integration. Maximum response achieved was PFB = 3.3 (M PEG 1500 g mol(-1), TLL 40 %). Enzyme characterization showed G6P Michaelis-Menten constant (K M ) equal 0.07-0.05, NADP(+) K M 0.02-1.98 and optimum temperature 70 °C, before and after recovery. Overall, our data confirmed feasibility of disruption/extraction integration for single-step purification of intracellular proteins from remaining yeast cells.

An oxygen-vacancy-rich Z-scheme g-C3N4/Pd/TiO2 heterostructure for enhanced visible light photocatalytic performance

Science.gov (United States)

Guo, Yanru; Xiao, Limin; Zhang, Min; Li, Qiuye; Yang, Jianjun

2018-05-01

An oxygen-vacancy-rich Z-scheme g-C3N4/Pd/TiO2 ternary nanocomposite was fabricated using nanotubular titanic acid as precursors via a simple photo-deposition of Pd nanoparticles and calcination process. The prepared nanocomposites were investigated by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-visible diffuse reflectance spectroscopy, respectively. For g-C3N4/TiO2 binary nanocomposites, at the optimal content of g-C3N4 (2%), the apparent photocatalytic activity of 2%g-C3N4/TiO2 was 9 times higher than that of pure TiO2 under visible-light illumination. After deposition of Pd (1 wt%) at the contact interface between g-C3N4 and TiO2, the 2%g-C3N4/Pd/TiO2 ternary nanocomposites demonstrated the highest visible-light-driven photocatalytic activity for the degradation of gaseous propylene, which was 16- and 2-fold higher activities than pure TiO2 and 2%g-C3N4/TiO2, respectively. The mechanism for the enhanced photocatalytic performance of the g-C3N4/Pd/TiO2 photo-catalyst is proposed to be based on the efficient separation of photo-generated electron-hole pairs through Z-scheme system, in which uniform dispersity of Pd nanoparticles at contact interface between g-C3N4 and TiO2 and oxygen vacancies promote charge separation.

D-glucose-6-phosphate dehydrogenase (Entner-Doudoroff enzyme) from Pseudomonas fluorescens

International Nuclear Information System (INIS)

Lessmann, D.; Schimz, K.L.; Kurz, G.

1975-01-01

The existence of two different D-glucose-6-phosphate dehydrogenases in Pseudomonas fluorescens has been demonstrated. Based on their different specificity and their different metabolic regulation one enzyme is appointed to the Entner-Doudoroff pathway and the other to the hexose monophosphate pathway. A procedure is described for the isolation of that D-glucose-6-phosphate dehydrogenase which forms part of the Entner-Doudoroff pathway (Entner-Doudoroff enzyme). A 950-fold purification was achieved with an overall yield of 44%. The final preparation, having a specific activity of about 300μmol NADH formed per min per mg protein, was shown to be homogeneous. The molecular weight of the Entner-Doudoroff enzyme has been determined to be 220,000 by gel permeation chromatography, and that of the other enzyme (Zwischenferment) has been shown to be 265,000. The pI of the Entner-Doudoroff enzyme has been shown to be 5.24 and that of the Zwischenferment 4.27. The Entner-Doudoroff enzyme is stable in the range of pH 6 to 10.5 and shows its maximal acivity at pH 8.9. The Entner-Doudoroff enzyme showed specificity for NAD + as well as for NADP + and exhibited homotropic effects for D-glucose 6-phosphate. It is inhibited by ATP which acts as a negative allosteric effector. Other nucleoside triphosphates as well as ADP are also inhibitory. The enzyme catalyzes the transfer of the axial hydrogen at carbon-1 of β-D-glucopyranose 6-phosphate to the si face of carbon-4 of the nicotinamide ring and must be classified as B-side stereospecific dehydrogenase. (orig.) [de

Orthodontic Force Application in Correlation with Salivary Lactate Dehydrogenase Activity

Directory of Open Access Journals (Sweden)

Erik Husin

2013-07-01

Full Text Available Orthodontic tooth movement generate mechanical forces to periodontal ligament and alveolar bone. The forces correlate with initial responses of periodontal tissues and involving many metabolic changes. One of the metabolic changes detected in saliva is lactate dehydrogenase (LDH activity. Objectives: To evaluate the correlation between orthodontic interrupted force application, lactate dehydrogenase activity and the distance of tooth movement. Methods: upper premolar, pre-retraction of upper canine and 1, 7, 14, 21 and 28 days post-retraction of upper canine with 100g interrupted orthodontic force. Results: duration of force (F=11.926 p 14 and 28 days post-retraction of canine. The region of retraction correlated with the distance of tooth movement (F=7.377 p=0.007. The duration of force correlated with the distance of tooth movement (F=66.554 p=0.000. retraction of canine. Conclusion: This study concluded that orthodontic interrupted force application on canine could increase the distance of tooth movement and LDH activity in saliva.

Central Nervous System Symptoms Due to Transient Methemoglobinemia in a Child With G6PD Deficiency.

Science.gov (United States)

Sharma, Shreya; Srinivasaraghavan, Rangan; Krishnamurthy, Sriram

2017-01-01

The authors herein report a 5-year-old child who presented with massive hemolysis, irritability, and cyanosis. The final diagnosis was glucose-6-phosphate dehydrogenase deficiency with associated central nervous system symptoms probably because of concomitantly acquired methemoglobinemia following oxidant drug exposure. The associated acute-onset anemia would have contributed to the development of cerebral anoxia-related seizures and encephalopathy.

Use of a simplified spectrophotometric method for quantitative determination of glucose-6-phosphate dehydrogenase activity in normal children from two day-care centers of the city of São Paulo

Directory of Open Access Journals (Sweden)

Roberto Muller

2003-06-01

Full Text Available Objective: To evaluate the applicability of a simplified method forquantitative determination of glucose-6-phosphate dehydrogenaseactivity in normal children; to determine the mean, standarddeviation and threshold value under which the enzyme activity isconsidered deficient. Methods: Blood samples were collected from201 children from two day-care centers in the city of São Paulo.The subjects were considered normal based on physicalexamination and laboratory tests. The enzyme activity wasdetermined in red blood cells of normal children using the “TestCombination G-6-PDH®” kit. The following statistical analyses werecarried out: the results were submitted to Student’s t test,Kolmogorov-Smirnov test, lower confidence interval (one-tailedtest and Spearman’s correlation coefficient. Results: The meanhemoglobin value for girls was slightly higher than the mean valuefor boys, but this difference was not statistically significant. Therewas no statistical difference in mean enzyme activities for Caucasianand non-Caucasian children. There was no significant correlation amongenzyme activity levels, red blood cells, hemoglobin levels,hematocrit, reticulocytes, white blood cells and age of patients.The mean enzyme activity for boys was 4.448 U/g Hb, standarddeviation = 1.380 U/g Hb. For girls, the mean enzyme activity was4.531 U/g Hb, standard deviation = 1.386 U/g Hb, and the differencewas not statistically significant. Therefore, the two populationgroups were considered as one single population, presenting amean enzyme activity of 4.490 U/g Hb, standard deviation = 1.380 U/g Hb.Since the distribution curve of enzyme activity values was normal,a lower confidence interval was determined (one-tailed test, witha cutoff point of 2.227 U/g Hb. Conclusion: The method used bySolem proved to be simple, fast, very accurate and useful to detectglucose-6-phosphate dehydrogenase activity and to identifychildren with enzyme deficiency.

Pd@HNTs-CDNS-g-C3N4: A novel heterogeneous catalyst for promoting ligand and copper-free Sonogashira and Heck coupling reactions, benefits from halloysite and cyclodextrin chemistry and g-C3N4 contribution to suppress Pd leaching.

Science.gov (United States)

Sadjadi, Samahe; Heravi, Majid M; Malmir, Masoumeh

2018-04-15

For the first time, a ternary hybrid system composed of halloysite nanotubes, HNTs, cyclodextrin nanosponges, CDNS, and g-C 3 N 4 is prepared and used for immobilization of Pd(0) nanoparticles and development of a heterogeneous catalyst, Pd@HNTs-CDNS-g-C 3 N 4 for promoting ligand and copper-free Sonogashira and Heck coupling reactions in aqueous media. HNT as a porous tubular clay with outstanding thermal, mechanical and textural properties can act as a support for immobilizing Pd nanoparticles. The role of CDNS can be explained on the base of its capability to form inclusion complexe with substrates and bringing them in the vicinity of the catalytic active sites. Regarding the role of g-C 3 N 4 in catalysis, it is proved that its presence can suppress the Pd leaching dramatically. The contribution of each component as well as synergistic effect between them results in high catalytic activity and recyclability (up to 10 reaction runs) of the catalyst. Copyright © 2018 Elsevier Ltd. All rights reserved.

Co-immobilization of cyclohexanone monooxygenase and glucose-6-phosphate dehydrogenase onto polyethylenimine-porous agarose polymeric composite using γ irradiation to use in biotechnological processes

International Nuclear Information System (INIS)

Atia, K.S.

2005-01-01

The co-immobilization of cyclohexanone monooxygenase (CHMO) and glucose-6-phosphate dehydrogenase (G6PDH) was optimized by completely coating, via covalent immobilization, the surface aldehyde groups of porous agarose (glyoxyl-agarose) with amine groups of polyethylenimine (PEI). The highest immobilization efficiency (∼87%) (activity of enzyme per amount of immobilized enzyme) was obtained with a CHMO/G6PDH ratio 2:1. The effects of different ratios of the support to the amount of enzymes (CHMO:G6PDH=2:1), the optimum incubation pH and the incubation time on the enzymatic activity of the enzymes were determined and found to be 5:1, 8.5 and 30 min, respectively. Subjecting the co-immobilized enzymes to doses of γ-radiation (5-100 kGy) resulted in complete loss in the activity of the free enzymes at a dose of 40 kGy, while the co-immobilized ones showed relatively high resistance to γ-radiation up to a dose of 50 kGy

One-step synthesis of PtPdAu ternary alloy nanoparticles on graphene with superior methanol electrooxidation activity

Energy Technology Data Exchange (ETDEWEB)

Zhang Yuzhen; Gu Yonge; Lin Shaoxiong; Wei Jinping; Wang Zaihua [Department of Chemistry, Lanzhou University, Lanzhou 730000 (China); Wang Chunming, E-mail: wangcm@lzu.edu.cn [Department of Chemistry, Lanzhou University, Lanzhou 730000 (China); Du Yongling; Ye Weichun [Department of Chemistry, Lanzhou University, Lanzhou 730000 (China)

2011-10-01

Highlights: > PtPdAu nanoparticles were synthesized on graphene sheets via chemical reduction method. > The prepared PtPdAu nanoparticles were ternary alloy with fcc structure. > The catalyst exhibited superior catalytic activity and stability for MOR in alkaline. - Abstract: Well-dispersed PtPdAu ternary alloy nanoparticles were synthesized on graphene sheets via a simple one-step chemical reduction method in ethylene glycol (EG) and water system, in which EG served as both reductive and dispersing agent. The electrocatalytic activity of PtPdAu/G was tested by methanol oxidation reaction (MOR). The catalyst was further characterized by transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD), which indicated that the as-synthesized PtPdAu nanoparticles with alloy structures were successfully dispersed on the graphene sheets. Electrocatalytic properties of the catalyst for MOR in alkaline have been investigated by cyclic voltammetry (CV), chronoamperometry and Tafel curves. The electrocatalytic activity and stability of PtPdAu/G were superior to PtPd/G, PtAu/G and Pt/G. In addition, the anodic peak current on PtPdAu/G catalyst was proportional to the concentration of methanol in the range of 0.05-1.00 M. This study implies that the prepared catalyst have great potential applications in fuel cells.

Differences in associations between markers of antioxidative defense and asthma are sex specific

DEFF Research Database (Denmark)

Malling, Tine Halsen; Sigsgaard, Torben; Andersen, Helle R

2010-01-01

on a screening questionnaire, random sampling, or both. Serum selenium concentrations and antioxidant enzyme activities (superoxide dismutase, glutathione peroxidase [GPX], glutathione reductase [GR], and glucose-6-phosphate dehydrogenase [G6PD]) in erythrocytes were measured. Asthma was defined as either...

Gaped deficiency distribution and variants in Saudi Arabia: An overview

International Nuclear Information System (INIS)

El-Hazmi, Mohsen A.F.; Warsy, Arjumand S.

2001-01-01

The first report of glucose-6-phosphate dehydrogenase (G6PD) deficiency in Saudi population of the Eastern Province paved the way for extensive investigations to determine the distribution and molecular pathogenesis of G6PD deficiency in Saudis in different parts of the country. During a national study lasting from 1980 to 1993, 24,407 Saudi in 31 different areas of Saudi Arabia screened for G6PD deficiency using spectrophoretic estimation of enzyme activity and electrophoretic separation of the phenotypes. The results in the males and females were separately analyzed and showed a statistically significant difference in the frequency in the male (0.0905) and female (0.041) population (P<0.05). The frequency in the male varied from 0 to 0.398 and in the female from 0 to 0.214. The phenotypes identified included G6PD-A, G6PD-Mediterranean and G6PD-Med-Like with G6PD-B as the normal phenotype in all areas. This study shows that G6PD deficiency is a frequently identified single-gene disorder in Saudi Arabia and G6PD-Mediterranean is the major variant producing the severe deficiency state in this population. (author)

Glucose-6-phosphate dehydrogenase: the key to sex-related xenobiotic toxicity in hepatocytes of European flounder (Platichthys flesus L.)?

NARCIS (Netherlands)

Winzer, Katja; van Noorden, Cornelis J. F.; Köhler, Angela

2002-01-01

The role of glucose-6-phosphate dehydrogenase (G6PDH) in oxidative stress responses was investigated in isolated intact living hepatocytes of immature female and male European flounder (Platichthys flesus L.) because it is the major provider of NADPH needed as reducing power for various

Catalytic properties of thermophilic lactate dehydrogenase and halophilic malate dehydrogenase at high temperature and low water activity.

Science.gov (United States)

Hecht, K; Wrba, A; Jaenicke, R

1989-07-15

Thermophilic lactate dehydrogenases from Thermotoga maritima and Bacillus stearothermophilus are stable up to temperature limits close to the optimum growth temperature of their parent organisms. Their catalytic properties are anomalous in that Km shows a drastic increase with increasing temperature. At low temperatures, the effect levels off. Extreme halophilic malate dehydrogenase from Halobacterium marismortui exhibits a similar anomaly. Increasing salt concentration (NaCl) leads to an optimum curve for Km, oxaloacctate while Km, NADH remains constant. Previous claims that the activity of halophilic malate dehydrogenase shows a maximum at 1.25 M NaCl are caused by limiting substrate concentration; at substrate saturation, specific activity of halophilic malate dehydrogenase reaches a constant value at ionic strengths I greater than or equal to 1 M. Non-halophilic (mitochondrial) malate dehydrogenase shows Km characteristics similar to those observed for the halophilic enzyme. The drastic decrease in specific activity of the mitochondrial enzyme at elevated salt concentrations is caused by the salt-induced increase in rigidity of the enzyme, rather than gross structural changes.

Glucose-6-phosphate dehydrogenase is required for hpa1xoo (harpin protein fragment)-mediated salt stress tolerance in transgenic arabidopsis thaliana

International Nuclear Information System (INIS)

Sang, S.L.; Xie, L.L.; Cui, X.W.; Wang, Z.Y.

2018-01-01

Harpin induces salicylic acid and abscisic acid signaling in plants under biotic and abiotic stress, respectively. Our previous report showed that the effective harpin fragment Hpa1xoo enhanced H2O2 production and pathogen resistance in a transgenic Arabidopsis mutant. In this study, we examined contents of thiobarbituric acid reactive substance (TBARS), H2O2 and glutathione, and glucose-6-phosphate dehydrogenase (G6PDH), glutathione reductase (GR) and glutathione peroxidase (GPX) enzyme activity in Hpa1xoo-expressing Arabidopsis under salt stress. The results revealed increased amounts of TBARS and H2O2 in wild-type (WT) compared to mutant plants under salt stress conditions. In contrast, increased levels were observed in the mutant under stress-free conditions. Moreover, a higher reduced glutathione (GSH) content and ratio of GSH/oxidized glutathione (GSSG) was observed in mutant compared to WT plants under both stress-free and salt stress conditions. In addition, mutant plants exhibited significantly higher G6PDH, GR and GPX activity than WT plants under salt stress. Suppression of G6PDH activity via 6-aminonicotinamide (6-AN, a specific inhibitor of G6PDH) was partly reversed by L-buthionine-sulfoximine (BSO, a specific inhibitor of GSH regeneration) and aggravated by GSH. Combined with previous reports, these findings suggest that the G6PDH enzyme plays a key role in harpin fragment (Hpa1xoo)-mediated salt stress tolerance in transgenic Arabidopsis. (author)

Fecal hydroxysteroid dehydrogenase activities in vegetarian Seventh-Day Adventists, control subjects, and bowel cancer patients.

Science.gov (United States)

Macdonald, I A; Webb, G R; Mahony, D E

1978-10-01

Cell-free extracts were prepared from mixed fecal anaerobic bacteria grown from stools of 14 vegetarian Seventh-Day Adventists, 16 omnivorous control subjects, and eight patients recently diagnosed with cancer of the large bowel. Preparations were assayed for NAD- and NADP-dependent 3alpha-, 7alpha- and 12alpha-hydroxysteroid dehydrogenases with bile salts and androsterone as substrates (eight substrate-cofactor combinations were tested). A significant intergroup difference was observed in the amounts of NAD- and NADP-dependent 7alpha-hydroxysteroid dehydrogenase produced: bowel cancer patients exceeded controls, and controls exceeded Seventh-Day Adventists. Other enzyme activity comparisons were not significant. The pH values of the stools were significantly higher in cancer patients compared to Seventh-Day Adventists; values were 7.03 +/- 0.60 and 6.46 +/- 0.58 respectively. The pH value for controls was 6.66 +/- 0.62. A plot of pH value versus NADP-dependent 7alpha-hydroxysteroid dehydrogenase tended to separate the cancer patients from the other groups. Comparative data suggest that much of the 3alpha-hydroxysteroid dehydrogenase active against bile salt is also active against androsterone.

Neonatal jaundice and glucose-6-phosphate dehydrogenase

OpenAIRE

Leite, Amauri Antiquera [UNESP

2010-01-01

A deficiência de glicose-6-fosfato desidrogenase em neonatos pode ser a responsável pela icterícia neonatal. Este comentário científico é decorrente do relato sobre o tema publicado neste fascículo e que preocupa diversos autores de outros países em relação às complicações em neonatos de hiperbilirrubinemia, existindo inclusive proposições de alguns autores em incluir o teste para identificar a deficiência de glicose-6-fosfato desidrogenase nos recém-nascidos.Glucose-6-phosphate dehydrogenase...

Machine learning prioritizes synthesis of primaquine ureidoamides with high antimalarial activity and attenuated cytotoxicity.

Science.gov (United States)

Levatić, Jurica; Pavić, Kristina; Perković, Ivana; Uzelac, Lidija; Ester, Katja; Kralj, Marijeta; Kaiser, Marcel; Rottmann, Matthias; Supek, Fran; Zorc, Branka

2018-02-25

Primaquine (PQ) is a commonly used drug that can prevent the transmission of Plasmodium falciparum malaria, however toxicity limits its use. We prepared five groups of PQ derivatives: amides 1a-k, ureas 2a-k, semicarbazides 3a,b, acylsemicarbazides 4a-k and bis-ureas 5a-v, and evaluated them for antimalarial activity in vitro against the erythrocytic stage of P. falciparum NF54. Particular substituents, such as trityl (in 2j and 5r) and methoxybenzhydryl (in 3b and 5v) were associated with a favorable cytotoxicity-to-activity ratio. To systematically link structural features of PQ derivatives to antiplasmodial activity, we performed a quantitative structure-activity relationship (QSAR) study using the Support Vector Machines machine learning method. This yielded a highly accurate statistical model (R 2  = 0.776 in cross-validation), which was used to prioritize novel candidate compounds. Seven novel PQ-ureidoamides 10a-g were synthesized and evaluated for activity, highlighting the benzhydryl ureidoamides 10e and 10f derived from p-chlorophenylglycine. Further experiments on human cell lines revealed that 10e and 10f are an order of magnitude less toxic than PQ in vitro while having antimalarial activity indistinguishable from PQ. The toxicity profile of novel compounds 10 toward human cells was particularly favorable when the glucose-6-phosphate dehydrogenase (G6PD) was inhibited, while toxicity of PQ was exacerbated by G6PD inhibition. Our work therefore highlights promising lead compounds for the development of effective antimalarial drugs that may also be safer for G6PD-deficient patients. In addition, we provide computational inferences of antimalarial activity and cytotoxicity for thousands of PQ-like molecular structures. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Rapid screening for glucose-6-phosphate dehydrogenase deficiency and haemoglobin polymorphisms in Africa by a simple high-throughput SSOP-ELISA method

DEFF Research Database (Denmark)

Enevold, Anders; Vestergaard, Lasse S; Lusingu, John

2005-01-01

was available. METHODS: A simple and rapid technique was developed to detect the most prominent single nucleotide polymorphisms (SNPs) in the HbB and G6PD genes. The method is able to detect the different haemoglobin polymorphisms A, S, C and E, as well as G6PD polymorphisms B, A and A- based on PCR......-amplification followed by a hybridization step using sequence-specific oligonucleotide probes (SSOPs) specific for the SNP variants and quantified by ELISA. RESULTS: The SSOP-ELISA method was found to be specific, and compared well to the commonly used PCR-RFLP technique. Identical results were obtained in 98......% (haemoglobin) and 95% (G6PD) of the tested 90 field samples from a high-transmission area in Tanzania, which were used to validate the new technique. CONCLUSION: The simplicity and accuracy of the new methodology makes it suitable for application in settings where resources are limited. It would serve...

PD1/PD1L pathway, HLA-G and T regulatory cells as new markers of immunosuppression in cancers

Directory of Open Access Journals (Sweden)

Paulina Własiuk

2016-10-01

Full Text Available The appropriate function of the immune system depends on the effective regulation of the immune response on multiple levels. The key element of an effective immune response to antigenic stimulation is maintaining a homeostasis between activation and inhibitory function of immunocompetent cells and molecules. In pathological conditions such as chronic infections, autoimmune diseases or cancer there are significant alterations, and prevalence of signals of one type over another. Main markers of these dysfunctions are altered expressions of molecules, such as programmed death-1 (PD-1, Human Leukocyte Antigen G (HLA-G, or changed percentages of T regulatory cells (Treg. These indicators of immune system dysfunction may contribute to disease progression, but also could represent good targets for treatment. Interestingly, in recent years there are many new, interesting reports which showed that the role of PD-1, HLA-G or Treg is ambiguous and not always their higher expression or frequency lead to the progression of disease. Recent studies have shown that Treg can suppress bacteria-driven inflammation which promotes carcinogenesis and thus protect the host from cancer development. Moreover, proliferation of hematological tumor cells expressing ILT-2 receptor can be inhibited by HLA-G, in contrast to solid tumors where HLA-G favors tumor escape. In this paper we present characteristics of expressions of PD-1 and its ligands, HLA-G, and frequency of Treg cells in a variety of physiological and pathological conditions associated with chronic infections, autoimmune diseases and cancer. The understanding of the complex interactions between the functional elements of immune system is essential for a detailed characteristics of the mechanisms leading to the development of diseases and identification of more effective targeted therapies.

Influence of Pd-precursor on the acetoxylation activity of Pd-Sb/TiO{sub 2} catalysts

Energy Technology Data Exchange (ETDEWEB)

Ben-homeid, A. [Benghazi Univ. (Libyan Arab Jamahiriya). Chemistry Dept.; Kalevaru, V.N.; Radnik, J.; Luecke, B.; Martin, A. [Leibniz-Institut fuer Katalyse e.V. an der Universitaet Rostock (Germany)

2013-11-01

The impact of palladium precursors (e.g. chloride-PdCl{sub 2}; acetate-Pd(OAc){sub 2}; nitrate-Pd(NO{sub 3}){sub 2}) on the catalytic properties of Pd-Sb/TiO{sub 2} catalysts used for acetoxylation of toluene has been investigated. The catalysts were characterized by different techniques such as N{sub 2}-adsorption (BET-surface area and pore volume), XRD, TEM, CO-Chemisorption and XPS for better understanding of the catalytic properties of the catalysts. The acetate and nitrate-type precursors exhibited higher surface areas, pore volumes and higher dispersion of Pd, but displayed poor performance compared to chloride precursor. TEM analysis indicated that the size of Pd particles depended upon the nature of Pd-precursor. Among the three, chloride precursor exhibited bigger Pd particles. XPS results revealed that all the fresh catalysts irrespective of Pd-precursor contained Pd in oxidized state (i.e. Pd{sup +2}), while in the spent catalysts such oxidized Pd species were reduced. The catalytic performance was found to depend strongly on the nature of precursor used. Among the three, the catalysts prepared from chloride-type precursor showed much higher overall catalytic activity (68%) than those of nitrate and/or acetate type precursors. Moreover, these two precursors (acetate and nitrate) gave higher total oxidation products due to oxidative decomposition of mainly acetic acid. Furthermore, the catalyst prepared from Cl-precursor revealed easy deactivation due to coke deposition and also due to loss of Pd in the near-surface-region. (orig.)

Toxicity of Nitrification Inhibitors on Dehydrogenase Activity in Soils

OpenAIRE

Ferisman Tindaon; Gero Benckiser; Johannes C. G. Ottow

2011-01-01

The objective of this research was to determine the effects of nitrification inhibitors (NIs) such as 3,4-dimethylpyrazolephosphate=DMPP, 4-Chlor-methylpyrazole phosphate=ClMPP and dicyandiamide,DCD) which might be expected to inhibit microbial activity, on dehydrogenase activity (DRA),in three different soils in laboratory conditions. Dehydrogenase activity were assessed via reduction of 2-p-Iodophenyl-3-p-nitrophenyl-5-phenyltetrazoliumchloride (INT). The toxicity and dose response curve of...

Glucose-6-phosphate dehydrogenase plays a pivotal role in nitric oxide-involved defense against oxidative stress under salt stress in red kidney bean roots.

Science.gov (United States)

Liu, Yinggao; Wu, Ruru; Wan, Qi; Xie, Gengqiang; Bi, Yurong

2007-03-01

The pivotal role of glucose-6-phosphate dehydrogenase (G-6-PDH)-mediated nitric oxide (NO) production in the tolerance to oxidative stress induced by 100 mM NaCl in red kidney bean (Phaseolus vulgaris) roots was investigated. The results show that the G-6-PDH activity was enhanced rapidly in the presence of NaCl and reached a maximum at 100 mM. Western blot analysis indicated that the increase of G-6-PDH activity in the red kidney bean roots under 100 mM NaCl was mainly due to the increased content of the G-6-PDH protein. NO production and nitrate reductase (NR) activity were also induced by 100 mM NaCl. The NO production was reduced by NaN(3) (an NR inhibitor), but not affected by N(omega)-nitro-L-arginine (L-NNA) (an NOS inhibitor). Application of 2.5 mM Na(3)PO(4), an inhibitor of G-6-PDH, blocked the increase of G-6-PDH and NR activity, as well as NO production in red kidney bean roots under 100 mM NaCl. The activities of antioxidant enzymes in red kidney bean roots increased in the presence of 100 mM NaCl or sodium nitroprusside (SNP), an NO donor. The increased activities of all antioxidant enzymes tested at 100 mM NaCl were completely inhibited by 2.5 mM Na(3)PO(4). Based on these results, we conclude that G-6-PDH plays a pivotal role in NR-dependent NO production, and in establishing tolerance of red kidney bean roots to salt stress.

Physiological and fermentation properties of Bacillus coagulans and a mutant lacking fermentative lactate dehydrogenase activity.

Science.gov (United States)

Su, Yue; Rhee, Mun Su; Ingram, Lonnie O; Shanmugam, K T

2011-03-01

Bacillus coagulans, a sporogenic lactic acid bacterium, grows optimally at 50-55 °C and produces lactic acid as the primary fermentation product from both hexoses and pentoses. The amount of fungal cellulases required for simultaneous saccharification and fermentation (SSF) at 55 °C was previously reported to be three to four times lower than for SSF at the optimum growth temperature for Saccharomyces cerevisiae of 35 °C. An ethanologenic B. coagulans is expected to lower the cellulase loading and production cost of cellulosic ethanol due to SSF at 55 °C. As a first step towards developing B. coagulans as an ethanologenic microbial biocatalyst, activity of the primary fermentation enzyme L-lactate dehydrogenase was removed by mutation (strain Suy27). Strain Suy27 produced ethanol as the main fermentation product from glucose during growth at pH 7.0 (0.33 g ethanol per g glucose fermented). Pyruvate dehydrogenase (PDH) and alcohol dehydrogenase (ADH) acting in series contributed to about 55% of the ethanol produced by this mutant while pyruvate formate lyase and ADH were responsible for the remainder. Due to the absence of PDH activity in B. coagulans during fermentative growth at pH 5.0, the l-ldh mutant failed to grow anaerobically at pH 5.0. Strain Suy27-13, a derivative of the l-ldh mutant strain Suy27, that produced PDH activity during anaerobic growth at pH 5.0 grew at this pH and also produced ethanol as the fermentation product (0.39 g per g glucose). These results show that construction of an ethanologenic B. coagulans requires optimal expression of PDH activity in addition to the removal of the LDH activity to support growth and ethanol production.

Glutathionylation regulates cytosolic NADP+-dependent isocitrate dehydrogenase activity.

Science.gov (United States)

Shin, Seoung Woo; Oh, Chang Joo; Kil, In Sup; Park, Jeen-Woo

2009-04-01

Cytosolic NADP+-dependent isocitrate dehydrogenase (IDPc) is susceptible to inactivation by numerous thiol-modifying reagents. This study now reports that Cys269 of IDPc is a target for S-glutathionylation and that this modification is reversed by dithiothreitol as well as enzymatically by cytosolic glutaredoxin in the presence of GSH. Glutathionylated IDPc was significantly less susceptible than native protein to peptide fragmentation by reactive oxygen species and proteolytic digestion. Glutathionylation may play a protective role in the degradation of protein through the structural alterations of IDPc. HEK293 cells treated with diamide displayed decreased IDPc activity and accumulated glutathionylated enzyme. Using immunoprecipitation with an anti-IDPc IgG and immunoblotting with an anti-GSH IgG, we purified and positively identified glutathionylated IDPc from the kidneys of mice subjected to ischemia/reperfusion injury and from the livers of ethanol-administered rats. These results suggest that IDPc activity is modulated through enzymatic glutathionylation and deglutathionylation during oxidative stress.

Determination of dehydrogenase activities involved in D-glucose oxidation in Gluconobacter and Acetobacter strains

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Florencia Sainz

2016-08-01

Full Text Available Acetic acid bacteria (AAB are known for rapid and incomplete oxidation of an extensively variety of alcohols and carbohydrates, resulting in the accumulation of organic acids as the final products. These oxidative fermentations in AAB are catalyzed by PQQ- or FAD- dependent membrane bound dehydrogenases. In the present study, the enzyme activity of the membrane bound dehydrogenases (membrane-bound PQQ-glucose dehydrogenase (mGDH, D-gluconate dehydrogenase (GADH and membrane-bound glycerol dehydrogenase (GLDH involved in the oxidation of D-glucose and D-gluconic acid (GA was determined in six strains of three different species of AAB (three natural and three type strains. Moreover, the effect of these activities on the production of related metabolites (GA, 2-keto-D-gluconic acid (2KGA and 5-keto-D-gluconic acid (5KGA was analyzed. The natural strains belonging to Gluconobacter showed a high mGDH activity and low activity in GADH and GLDH, whereas the A. malorum strain presented low activity in the three enzymes. Nevertheless, no correlation was observed between the activity of these enzymes and the concentration of the corresponding metabolites. In fact, all the tested strains were able to oxidize D-glucose to GA, being maximal at the late exponential phase of the AAB growth (24 h, which coincided with glucose exhaustion and the maximum mGDH activity. Instead, only some of the tested strains were capable of producing 2KGA and/or 5KGA. In the case of G. oxydans strains, no 2KGA production was detected which is related to the absence of GADH activity after 24 h, while in the remaining strains, detection of GADH activity after 24h resulted in a high accumulation of 2KGA. Therefore, it is possible to choose the best strain depending on the desired product composition.Moreover, the sequences of these genes were used to construct phylogenetic trees. According to the sequence of gcd, gene coding for mGDH, Acetobacter and Komagataeibacter were

Enhanced Activity and Selectivity of Carbon Nanofiber Supported Pd Catalysts for Nitrite Reduction

KAUST Repository

Shuai, Danmeng; Choe, Jong Kwon; Shapley, John R.; Werth, Charles J.

2012-01-01

Pd-based catalyst treatment represents an emerging technology that shows promise to remove nitrate and nitrite from drinking water. In this work we use vapor-grown carbon nanofiber (CNF) supports in order to explore the effects of Pd nanoparticle size and interior versus exterior loading on nitrite reduction activity and selectivity (i.e., dinitrogen over ammonia production). Results show that nitrite reduction activity increases by 3.1-fold and selectivity decreases by 8.0-fold, with decreasing Pd nanoparticle size from 1.4 to 9.6 nm. Both activity and selectivity are not significantly influenced by Pd interior versus exterior CNF loading. Consequently, turnover frequencies (TOFs) among all CNF catalysts are similar, suggesting nitrite reduction is not sensitive to Pd location on CNFs nor Pd structure. CNF-based catalysts compare favorably to conventional Pd catalysts (i.e., Pd on activated carbon or alumina) with respect to nitrite reduction activity and selectivity, and they maintain activity over multiple reduction cycles. Hence, our results suggest new insights that an optimum Pd nanoparticle size on CNFs balances faster kinetics with lower ammonia production, that catalysts can be tailored at the nanoscale to improve catalytic performance for nitrite, and that CNFs hold promise as highly effective catalyst supports in drinking water treatment. © 2012 American Chemical Society.

Enhanced Activity and Selectivity of Carbon Nanofiber Supported Pd Catalysts for Nitrite Reduction

KAUST Repository

Shuai, Danmeng

2012-03-06

Pd-based catalyst treatment represents an emerging technology that shows promise to remove nitrate and nitrite from drinking water. In this work we use vapor-grown carbon nanofiber (CNF) supports in order to explore the effects of Pd nanoparticle size and interior versus exterior loading on nitrite reduction activity and selectivity (i.e., dinitrogen over ammonia production). Results show that nitrite reduction activity increases by 3.1-fold and selectivity decreases by 8.0-fold, with decreasing Pd nanoparticle size from 1.4 to 9.6 nm. Both activity and selectivity are not significantly influenced by Pd interior versus exterior CNF loading. Consequently, turnover frequencies (TOFs) among all CNF catalysts are similar, suggesting nitrite reduction is not sensitive to Pd location on CNFs nor Pd structure. CNF-based catalysts compare favorably to conventional Pd catalysts (i.e., Pd on activated carbon or alumina) with respect to nitrite reduction activity and selectivity, and they maintain activity over multiple reduction cycles. Hence, our results suggest new insights that an optimum Pd nanoparticle size on CNFs balances faster kinetics with lower ammonia production, that catalysts can be tailored at the nanoscale to improve catalytic performance for nitrite, and that CNFs hold promise as highly effective catalyst supports in drinking water treatment. © 2012 American Chemical Society.

Kernicterus by glucose-6-phosphate dehydrogenase deficiency: a case report and review of the literature

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Cossio de Gurrola Gladys

2008-05-01

Full Text Available Abstract Introduction Glucose-6-phosphate dehydrogenase deficiency is an X-linked recessive disease that causes acute or chronic hemolytic anemia and potentially leads to severe jaundice in response to oxidative agents. This deficiency is the most common human innate error of metabolism, affecting more than 400 million people worldwide. Case presentation Here, we present the first documented case of kernicterus in Panama, in a glucose-6-phosphate dehydrogenase-deficient newborn clothed in naphthalene-impregnated garments, resulting in reduced psychomotor development, neurosensory hypoacousia, absence of speech and poor reflex of the pupil to light. Conclusion Mutational analysis revealed the glucose-6-phosphate dehydrogenase Mediterranean polymorphic variant, which explained the development of kernicterus after exposition of naphthalene. As the use of naphthalene in stored clothes is a common practice, glucose-6-phosphate dehydrogenase testing in neonatal screening could prevent severe clinical consequences.

High prevalence of Dapsone-induced oxidant hemolysis in North American SCT recipients without glucose-6-phosphate-dehydrogenase deficiency.

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Olteanu, H; Harrington, A M; George, B; Hari, P N; Bredeson, C; Kroft, S H

2012-03-01

Dapsone (4-4'-diaminodiphenylsulfone) is commonly used for Pneumocystis jirovecii pneumonia (PCP) prophylaxis in immunocompromised patients. Oxidant hemolysis is a known complication of dapsone, but its frequency in adult patients who have undergone a SCT for hematological malignancies is not well established. We studied the presence of oxidant hemolysis, by combining examination of RBC morphology and laboratory data, in 30 patients who underwent a SCT and received dapsone for PCP prophylaxis, and compared this group with 26 patients who underwent a SCT and received trimethoprim-sulfamethoxazole (TMP-SMX) for PCP prophylaxis. All patients had normal glucose-6-phosphate dehydrogenase (G6PDH) enzymatic activity. In SCT patients, dapsone compared with TMP-SMX for PCP prophylaxis was associated with a high incidence of oxidant hemolysis (87 vs 0%, PSCT patients is 20-fold higher than the reported rate in the population of HIV-infected patients, and thus much higher than the prevalence of G6PDH variants in the general population. In our patients, it manifested clinically as a lower Hb that was not significant enough to result in increased packed RBC transfusions.

Construction of mutant glucose oxidases with increased dye-mediated dehydrogenase activity.

Science.gov (United States)

Horaguchi, Yohei; Saito, Shoko; Kojima, Katsuhiro; Tsugawa, Wakako; Ferri, Stefano; Sode, Koji

2012-11-02

Mutagenesis studies on glucose oxidases (GOxs) were conducted to construct GOxs with reduced oxidase activity and increased dehydrogenase activity. We focused on two representative GOxs, of which crystal structures have already been reported—Penicillium amagasakiense GOx (PDB ID; 1gpe) and Aspergillus niger GOx (PDB ID; 1cf3). We constructed oxygen-interacting structural models for GOxs, and predicted the residues responsible for oxidative half reaction with oxygen on the basis of the crystal structure of cholesterol oxidase as well as on the fact that both enzymes are members of the glucose/methanol/choline (GMC) oxidoreductase family. Rational amino acid substitution resulted in the construction of an engineered GOx with drastically decreased oxidase activity and increased dehydrogenase activity, which was higher than that of the wild-type enzyme. As a result, the dehydrogenase/oxidase ratio of the engineered enzyme was more than 11-fold greater than that of the wild-type enzyme. These results indicate that alteration of the dehydrogenase/oxidase activity ratio of GOxs is possible by introducing a mutation into the putative functional residues responsible for oxidative half reaction with oxygen of these enzymes, resulting in a further increased dehydrogenase activity. This is the first study reporting the alteration of GOx electron acceptor preference from oxygen to an artificial electron acceptor.

Construction of Mutant Glucose Oxidases with Increased Dye-Mediated Dehydrogenase Activity

Science.gov (United States)

Horaguchi, Yohei; Saito, Shoko; Kojima, Katsuhiro; Tsugawa, Wakako; Ferri, Stefano; Sode, Koji

2012-01-01

Mutagenesis studies on glucose oxidases (GOxs) were conducted to construct GOxs with reduced oxidase activity and increased dehydrogenase activity. We focused on two representative GOxs, of which crystal structures have already been reported—Penicillium amagasakiense GOx (PDB ID; 1gpe) and Aspergillus niger GOx (PDB ID; 1cf3). We constructed oxygen-interacting structural models for GOxs, and predicted the residues responsible for oxidative half reaction with oxygen on the basis of the crystal structure of cholesterol oxidase as well as on the fact that both enzymes are members of the glucose/methanol/choline (GMC) oxidoreductase family. Rational amino acid substitution resulted in the construction of an engineered GOx with drastically decreased oxidase activity and increased dehydrogenase activity, which was higher than that of the wild-type enzyme. As a result, the dehydrogenase/oxidase ratio of the engineered enzyme was more than 11-fold greater than that of the wild-type enzyme. These results indicate that alteration of the dehydrogenase/oxidase activity ratio of GOxs is possible by introducing a mutation into the putative functional residues responsible for oxidative half reaction with oxygen of these enzymes, resulting in a further increased dehydrogenase activity. This is the first study reporting the alteration of GOx electron acceptor preference from oxygen to an artificial electron acceptor. PMID:23203056

Quantitative aspects of the cytochemical demonstration of glucose-6-phosphate dehydrogenase with tetrazolium salts studied in a model system of polyacrylamide films

NARCIS (Netherlands)

van Noorden, C. J.; Tas, J.; Sanders, J. A.

1981-01-01

The enzyme cytochemical demonstration of glucose-6-phosphate dehydrogenase (G6PDH) with several tetrazolium salts has been studied with an artificial model of polyacrylamide films in corporated with the enzyme, which enabled teh correlation of cytochemical and biochemical data. In the model films no

Protective effects of glucose-6-phosphate dehydrogenase on neurotoxicity of aluminium applied into the CA1 sector of rat hippocampus

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Marina D Jovanovic

2014-01-01

Full Text Available Background & objectives: Aluminum (Al toxicity is closely linked to the pathogenesis of Alzheimer′s disease (AD. This experimental study was aimed to investigate the active avoidance behaviour of rats after intrahippocampal injection of Al, and biochemical and immunohistochemical changes in three bilateral brain structures namely, forebrain cortex (FBCx, hippocampus and basal forebrain (BF. Methods: Seven days after intra-hippocampal (CA1 sector injection of AlCl 3 into adult male Wistar rats they were subjected to two-way active avoidance (AA tests over five consecutive days. Control rats were treated with 0.9% w/v saline. The animals were decapitated on the day 12 post-injection. The activities of acetylcholinesterase (AChE and glucose-6-phosphate dehydrogenase (G6PDH were measured in the FBCx, hippocampus and BF. Immunohistochemical staining was performed for transferrin receptors, amyloid β and tau protein. Results: The activities of both AChE and G6PDH were found to be decreased bilaterally in the FBCx, hippocampus and basal forebrain compared to those of control rats. The number of correct AA responses was reduced by AlCl 3 treatment. G6PDH administered prior to AlCl 3 resulted in a reversal of the effects of AlCl 3 on both biochemical and behavioural parameters. Strong immunohistochemical staining of transferrin receptors was found bilaterally in the FBCx and the hippocampus in all three study groups. In addition, very strong amyloid β staining was detected bilaterally in all structures in AlCl 3 -treated rats but was moderate in G6PDH/AlCl 3 -treated rats. Strong tau staining was noted bilaterally in AlCl 3 -treated rats. In contrast, tau staining was only moderate in G6PDH/AlCl 3 -treated rats. Interpretation & conclusions: Our findings indicated that the G6PDH alleviated the signs of behavioural and biochemical effects of AlCl 3 -treatment suggesting its involvement in the pathogenesis of Al neurotoxicity and its potential

Peroxyl radical- and photo-oxidation of glucose 6- phosphate dehydrogenase generates cross-links and functional changes via oxidation of tyrosine and tryptophan residues

DEFF Research Database (Denmark)

Leinisch, Fabian; Mariotti, Michele; Rykær, Martin

2017-01-01

indicate that pathophysiological processes and multiple human diseases are associated with the accumulation of damaged proteins. In this study we investigated the mechanisms and consequences of exposure of the key metabolic enzyme glucose-6-phosphate dehydrogenase (G6PDH) to peroxyl radicals (ROO...

The Enzyme Activity and Substrate Specificity of Two Major Cinnamyl Alcohol Dehydrogenases in Sorghum (Sorghum bicolor), SbCAD2 and SbCAD4.

Science.gov (United States)

Jun, Se-Young; Walker, Alexander M; Kim, Hoon; Ralph, John; Vermerris, Wilfred; Sattler, Scott E; Kang, ChulHee

2017-08-01

Cinnamyl alcohol dehydrogenase (CAD) catalyzes the final step in monolignol biosynthesis, reducing sinapaldehyde, coniferaldehyde, and p -coumaraldehyde to their corresponding alcohols in an NADPH-dependent manner. Because of its terminal location in monolignol biosynthesis, the variation in substrate specificity and activity of CAD can result in significant changes in overall composition and amount of lignin. Our in-depth characterization of two major CAD isoforms, SbCAD2 (Brown midrib 6 [bmr6]) and SbCAD4, in lignifying tissues of sorghum ( Sorghum bicolor ), a strategic plant for generating renewable chemicals and fuels, indicates their similarity in both structure and activity to Arabidopsis ( Arabidopsis thaliana ) CAD5 and Populus tremuloides sinapyl alcohol dehydrogenase, respectively. This first crystal structure of a monocot CAD combined with enzyme kinetic data and a catalytic model supported by site-directed mutagenesis allows full comparison with dicot CADs and elucidates the potential signature sequence for their substrate specificity and activity. The L119W/G301F-SbCAD4 double mutant displayed its substrate preference in the order coniferaldehyde > p -coumaraldehyde > sinapaldehyde, with higher catalytic efficiency than that of both wild-type SbCAD4 and SbCAD2. As SbCAD4 is the only major CAD isoform in bmr6 mutants, replacing SbCAD4 with L119W/G301F-SbCAD4 in bmr6 plants could produce a phenotype that is more amenable to biomass processing. © 2017 American Society of Plant Biologists. All Rights Reserved.

Deletion of the Glucose-6-Phosphate Dehydrogenase Gene KlZWF1 Affects both Fermentative and Respiratory Metabolism in Kluyveromyces lactis▿

Science.gov (United States)

Saliola, Michele; Scappucci, Gina; De Maria, Ilaria; Lodi, Tiziana; Mancini, Patrizia; Falcone, Claudio

2007-01-01

In Kluyveromyces lactis, the pentose phosphate pathway is an alternative route for the dissimilation of glucose. The first enzyme of the pathway is the glucose-6-phosphate dehydrogenase (G6PDH), encoded by KlZWF1. We isolated this gene and examined its role. Like ZWF1 of Saccharomyces cerevisiae, KlZWF1 was constitutively expressed, and its deletion led to increased sensitivity to hydrogen peroxide on glucose, but unlike the case for S. cerevisiae, the Klzwf1Δ strain had a reduced biomass yield on fermentative carbon sources as well as on lactate and glycerol. In addition, the reduced yield on glucose was associated with low ethanol production and decreased oxygen consumption, indicating that this gene is required for both fermentation and respiration. On ethanol, however, the mutant showed an increased biomass yield. Moreover, on this substrate, wild-type cells showed an additional band of activity that might correspond to a dimeric form of G6PDH. The partial dimerization of the G6PDH tetramer on ethanol suggested the production of an NADPH excess that was negative for biomass yield. PMID:17085636

Construction of Mutant Glucose Oxidases with Increased Dye-Mediated Dehydrogenase Activity

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Koji Sode

2012-11-01

Full Text Available Mutagenesis studies on glucose oxidases (GOxs were conducted to construct GOxs with reduced oxidase activity and increased dehydrogenase activity. We focused on two representative GOxs, of which crystal structures have already been reported—Penicillium amagasakiense GOx (PDB ID; 1gpe and Aspergillus niger GOx (PDB ID; 1cf3. We constructed oxygen-interacting structural models for GOxs, and predicted the residues responsible for oxidative half reaction with oxygen on the basis of the crystal structure of cholesterol oxidase as well as on the fact that both enzymes are members of the glucose/methanol/choline (GMC oxidoreductase family. Rational amino acid substitution resulted in the construction of an engineered GOx with drastically decreased oxidase activity and increased dehydrogenase activity, which was higher than that of the wild-type enzyme. As a result, the dehydrogenase/oxidase ratio of the engineered enzyme was more than 11-fold greater than that of the wild-type enzyme. These results indicate that alteration of the dehydrogenase/oxidase activity ratio of GOxs is possible by introducing a mutation into the putative functional residues responsible for oxidative half reaction with oxygen of these enzymes, resulting in a further increased dehydrogenase activity. This is the first study reporting the alteration of GOx electron acceptor preference from oxygen to an artificial electron acceptor.

Prophylactic Role of Spermine in Rats Intoxicated With Lead and/or Gamma Irradiation

International Nuclear Information System (INIS)

Habieb, M.E.; Mohamed, M.A.; Hawas, A.M.; Abu-Khudir, R.; Mohamed, T.M.

2017-01-01

The current study was conducted to investigate the protective effect of spermine, a natural polyamine against toxicity of lead and /or gamma irradiation in male rats. Eight groups of rats were used in this study (control, irradiated group (6 GY), lead (40 mg/kg bw), spermine (10 mg/kg bw), lead plus irradiation, irradiation plus spermine, lead plus spermine, irradiation plus lead co-treated with spermine) for consecutive 14 days. Blood samples were used for complete blood count (CBC) and glucose 6-phosphate-dehydrogenase (G6PD) levels. Moreover, malondialdhyde (MDA), glutathione (GSH), metallothionein (MT) levels and catalase (CAT) activity were investigated in liver, kidney and brain. G6PD activity significantly decreased post exposure to lead and /or gamma irradiation. Hepatic, renal and brain MDA, GSH, MT and CAT were significantly increased in lead intoxicated group, while GSH, MT and CAT activity were significantly decreased in gamma-irradiated group. Spermine administration alleviated changes in CBC, G6PD, MDA, MT and CAT to normal control levels, but with significant increase in G6PD activity and platelets count. In conclusion, spermine acts as an antioxidant and plays a prophylactic role against intoxication with lead and/or gamma irradiation exposure.

High-Throughput, Multiplex Genotyping Directly from Blood or Dried Blood Spot without DNA Extraction for the Screening of Multiple G6PD Gene Variants at Risk for Drug-Induced Hemolysis.

Science.gov (United States)

Tian, Xiaoyi; Zhou, Jun; Zhao, Ye; Cheng, Zhibin; Song, Wenqi; Sun, Yu; Sun, Xiaodong; Zheng, Zhi

2017-09-01

Clinical or epidemiologic screening of single-nucleotide polymorphism markers requires large-scale multiplexed genotyping. Available genotyping tools require DNA extraction and multiplex PCR, which may limit throughput and suffer amplification bias. Herein, a novel genotyping approach has been developed, multiplex extension and ligation-based probe amplification (MELPA), which eliminates DNA extraction and achieves uniform PCR amplification. MELPA lyses blood or dried blood spot and directly captures specific target DNA to 96-well plates using tailed probes. Subsequent enzymatic extension and ligation form target single-nucleotide polymorphism-spanning single-stranded templates, which are PCR-amplified using universal primers. Multiplexed genotyping by single-base primer extension is analyzed by mass spectrometry, with a call rate >97%. MELPA was compared with a commercial assay (iPLEX) for detecting 24 G6PD variants known to be at risk for primaquine-induced hemolysis. MELPA provided results that were more reliable than iPLEX, with higher throughput and lower cost. Genotyping archival blood from 106 malaria patients taking primaquine found 10 G6PD-deficient variants, including 1 patient with a hemizygous Mahidol mutation who had hemolysis. Preemptive G6PD genotyping of 438 dried blood spots from a malaria-endemic area identified three variants. MELPA also enabled pooled genotyping without diluting rare alleles, in which undesired common-allele background increased by sample pooling can be repressed by adding specific common allele blockers. Thus, MELPA represents a high-throughput, cost-effective approach to targeted genotyping at the population level. Copyright © 2017 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

Silencing of cytosolic NADP+-dependent isocitrate dehydrogenase gene enhances ethanol-induced toxicity in HepG2 cells.

Science.gov (United States)

Yang, Eun Sun; Lee, Su-Min; Park, Jeen-Woo

2010-07-01

It has been shown that acute and chronic alcohol administrations increase the production of reactive oxygen species, lower cellular antioxidant levels and enhance oxidative stress in many tissues. We recently reported that cytosolic NADP(+)-dependent isocitrate dehydrogenase (IDPc) functions as an antioxidant enzyme by supplying NADPH to the cytosol. Upon exposure to ethanol, IDPc was susceptible to the loss of its enzyme activity in HepG2 cells. Transfection of HepG2 cells with an IDPc small interfering RNA noticeably downregulated IDPc and enhanced the cells' vulnerability to ethanol-induced cytotoxicity. Our results suggest that suppressing the expression of IDPc enhances ethanol-induced toxicity in HepG2 cells by further disruption of the cellular redox status.

Benfotiamine improves functional recovery of the infarcted heart via activation of pro-survival G6PD/Akt signaling pathway and modulation of neurohormonal response.

Science.gov (United States)

Katare, Rajesh; Caporali, Andrea; Emanueli, Costanza; Madeddu, Paolo

2010-10-01

Benfotiamine (BFT) is a transketolase activator that directs glucose to the pentose phosphate pathway. The present study investigated whether BFT improves the recovery after myocardial infarction (MI) and explored underlying mechanisms of protection. Non-diabetic and streptozotocin-induced type 1 diabetic mice were supplemented with BFT (70 mg/kg/day in drinking water) for 4 weeks and then subjected to MI or sham operation. Cardiac function was monitored by echocardiography. At two weeks post-MI, intra-ventricular pressure was measured by Millar tip-catheter and hearts were collected for biochemical, immunohistochemical and expressional analyses. No treatment effect was observed in sham-operated mice. Post-MI mortality was higher in diabetic mice and hemodynamic studies confirmed the worsening effect of diabetes on functional recovery. Furthermore, diabetic mice demonstrated increased cardiomyocyte apoptosis, reduced reparative angiogenesis, larger scars, enhanced oxidative stress, and blunted activation of the pro-survival VEGF receptor-2/Akt/Pim-1 signaling pathway. BFT improved post-MI survival, functional recovery and neovascularization and reduced cardiomyocyte apoptosis and neurohormonal activation in diabetic as well as in non-diabetic mice. In addition, BFT stimulated the activity of pentose phosphate pathway enzymes, leading to reduction of oxidative stress, phosphorylation/activation of VEGF receptor-2 and Akt and increased Pim-1, pBad and Bcl-2 levels. These effects were contrasted on silencing glucose-6-phosphate dehydrogenase, the key enzyme in pentose phosphate pathway, or inhibiting Akt. BFT benefits post-MI recovery through stimulation of pro-survival mechanisms and containment of neurohormonal response. These results may have implications for the treatment of myocardial ischemia. Copyright © 2010 Elsevier Ltd. All rights reserved.

Intravenous immunoglobulin to treat hyperbilirubinemia in neonates with isolated Glucose-6-Phosphate dehydrogenase deficiency

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Wadah Khriesat

2017-04-01

Full Text Available Background Glucose-6-phosphate dehydrogenase deficiency alone or concomitant with ABO isoimmunisation is a widespread indication for neonatal exchange transfusion. Aims To evaluate the effectiveness of Intravenous Immunoglobulin in the treatment of neonatal hyperbilirubinemia due to glucose-6-phosphate dehydrogenase deficiency. Methods A retrospective cohort study was conducted between 2006 and 2014 at the Jordan University of Science and technology. The medical records of 43 infants admitted to the neonatal intensive care unit for isolated glucose-6- phosphate dehydrogenase deficiency hemolytic disease of the newborns were reviewed. Patients were divided into two groups. Group I, a historical cohort, included newborns born between 2006 and 2010, Treatment included phototherapy and exchange transfusion. Group II included newborns born between 2011 and 2014, where, in addition to phototherapy, intravenous immunoglobulin was administered. The duration of phototherapy and number of exchange transfusions were evaluated. Results Of 412 newborns that were admitted with neonatal hyperbilirubinemia, Glucose-6-phosphate dehydrogenase deficiency was present in 43. Of these, 22, did not receive intravenous immunoglobulin and served as a control group. The other 21 newborns received intravenous immunoglobulin. There was no difference in the demographic characteristics between the two groups. Infants in the control group were significantly more likely to receive exchange blood transfusion than infants in the immunoglobulin treatment group, but were significantly less likely to need phototherapy. Conclusion Intravenous immunoglobulin is an effective alternative to exchange transfusion in infants with glucose-6-phosphate dehydrogenase deficiency hemolytic disease of the newborn. It is suggested that intravenous immunoglobulin may be beneficial as a prophylaxis for infants with hyperbilirubinemia.

Photocatalytic reductive dechlorination of 2-chlorodibenzo-p-dioxin by Pd modified g-C3N4 photocatalysts under UV-vis irradiation: Efficacy, kinetics and mechanism.

Science.gov (United States)

Ding, Jiafeng; Long, Gaoyuan; Luo, Yang; Sun, Runze; Chen, Mengxia; Li, Yajun; Zhou, Yanfang; Xu, Xinhua; Zhao, Weirong

2018-05-09

Polychlorinated dibenzo-p-dioxins (PCDDs), as a group of notorious anthropogenic environmental toxicants, are arguably ubiquitous in nature. In this study, we investigated the photocatalytic reductive dechlorination of 2-chlorodibenzo-p-dioxin (2-CDD) over Pd/g-C 3 N 4 catalysts under UV-vis irradiation. The g-C 3 N 4 and a series of Pd/g-C 3 N 4 catalysts were prepared by thermal polymerization and mechanical mixing-illumination method and characterized by XRD, TEM, BET, SEM and UV-vis DRS analyses. Among all the samples, the Pd/g-C 3 N 4 (5 wt%) yielded the optimal dechlorination activity with a total 2-CDD conversion of 54% within 4 h, and 76% of those converted 2-CDD were evolved to dibenzo-p-dioxin (DD). The kinetics of dechlorination could be described as pseudo-first-order decay model (R 2  > 0.84). Corresponding rate constants (k) increased from 0.052 to 0.17 h -1 with Pd contents up to 5 wt% and decreased to 0.13 h -1 with a 10 wt% of Pd. The enhanced activities originated from the surface plasmonic resonance (SPR) effect of Pd nanoparticles and the formation of Schottky barrier between Pd and g-C 3 N 4 , which extend the spectrum responsive range and suppress the charge recombination of g-C 3 N 4 . This is the first report on the photocatalytic reductive removal of PCDDs and may provide a new approach for PCDDs pollution control. Copyright © 2018 Elsevier B.V. All rights reserved.

9-Hydroxyprostaglandin dehydrogenase activity in the adult rat kidney. Regional distribution and sub-fractionation.

Science.gov (United States)

Asciak, C P; Domazet, Z

1975-02-20

1. Catabolism of prostaglandin F2alpha in the adult rat kidney takes place by the following sequence of enzymatic steps: (1) 15-hydroxyprostaglandin dehydrogenase; (2) prostaglandin delta13-reductase; and (3) 9-hydroxyprostaglandin dehydrogenase. 2. 9-Hydroxyprostaglandin dehydrogenase activity was highest in the cortex with lesser amounts in the medulla and negligible activity detected in the papilla. A similar distribution was observed for 15-hydroxyprostaglandin dehydrogenase and prostaglandin delta13-reductase. 3. Most of the 9-hydroxyprostaglandin dehydrogenase activity in the homogenate was found in the high-speed supernatant as also observed for 15-hydroxyprostaglandin dehydrogenase and prostaglandin delta13-reductase. 4. These observations indicate that the rat kidney contains an abundance of prostaglandin-catabolising enzymes which favour formation of metabolites of the E-type.

Mechanisms of activation of muscle branched-chain alpha-keto acid dehydrogenase during exercise in man

DEFF Research Database (Denmark)

Van Hall, Gerrit; MacLean, D A; Saltin, B

1996-01-01

1. Exercise leads to activation (dephosphorylation) of the branched-chain alpha-keto acid dehydrogenase (BCKADH). Here we investigate the effect of low pre-exercise muscle glycogen content and of branched-chain amino acid (BCAA) ingestion on the activity of BCKADH at rest and after 90 min of one......-leg knee-extensor exercise at 65% maximal one-leg power output in five subjects. 2. Pre-exercise BCAA ingestion (308 mg BCAAs (kg body wt)-1) caused an increased muscle BCAA uptake, a higher intramuscular BCAA concentration and activation of BCKADH both at rest (9 +/- 1 versus 25 +/- 5% for the control...... and BCAA test, respectively) and after exercise (27 +/- 4 versus 54 +/- 7%). 3. At rest the percentage active BCKADH was not different, 6 +/- 2% versus 5 +/- 1%, in the normal and low glycogen content leg (392 +/- 21 and 147 +/- 34 mumol glycosyl units (g dry muscle)-1, respectively). The post...

Candida albicans Hom6 is a homoserine dehydrogenase involved in protein synthesis and cell adhesion

Directory of Open Access Journals (Sweden)

Pei-Wen Tsai

2017-12-01

Full Text Available Background/Purpose: Candida albicans is a common fungal pathogen in humans. In healthy individuals, C. albicans represents a harmless commensal organism, but infections can be life threatening in immunocompromised patients. The complete genome sequence of C. albicans is extremely useful for identifying genes that may be potential drug targets and important for pathogenic virulence. However, there are still many uncharacterized genes in the Candida genome database. In this study, we investigated C. albicans Hom6, the functions of which remain undetermined experimentally. Methods: HOM6-deleted and HOM6-reintegrated mutant strains were constructed. The mutant strains were compared with wild-type in their growth in various media and enzyme activity. Effects of HOM6 deletion on translation were further investigated by cell susceptibility to hygromycin B or cycloheximide, as well as by polysome profiling, and cell adhesion to polystyrene was also determined. Results: C. albicans Hom6 exhibits homoserine dehydrogenase activity and is involved in the biosynthesis of methionine and threonine. HOM6 deletion caused translational arrest in cells grown under amino acid starvation conditions. Additionally, Hom6 protein was found in both cytosolic and cell-wall fractions of cultured cells. Furthermore, HOM6 deletion reduced C. albicans cell adhesion to polystyrene, which is a common plastic used in many medical devices. Conclusion: Given that there is no Hom6 homologue in mammalian cells, our results provided an important foundation for future development of new antifungal drugs. Keywords: Candida albicans, cell adhesion, Hom6, homoserine dehydrogenase, protein synthesis

Aminotransferase and glutamate dehydrogenase activities in lactobacilli and streptococci

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Guillermo Hugo Peralta

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

Highly Stable l-Lysine 6-Dehydrogenase from the Thermophile Geobacillus stearothermophilus Isolated from a Japanese Hot Spring: Characterization, Gene Cloning and Sequencing, and Expression

Science.gov (United States)

Heydari, Mojgan; Ohshima, Toshihisa; Nunoura-Kominato, Naoki; Sakuraba, Haruhiko

2004-01-01

l-Lysine dehydrogenase, which catalyzes the oxidative deamination of l-lysine in the presence of NAD, was found in the thermophilic bacterium Geobacillus stearothermophilus UTB 1103 and then purified about 3,040-fold from a crude extract of the organism by using four successive column chromatography steps. This is the first report showing the presence of a thermophilic NAD-dependent lysine dehydrogenase. The product of the enzyme catalytic activity was determined to be Δ1-piperideine-6-carboxylate, indicating that the enzyme is l-lysine 6-dehydrogenase (LysDH) (EC 1.4.1.18). The molecular mass of the purified protein was about 260 kDa, and the molecule was determined to be a homohexamer with subunit molecular mass of about 43 kDa. The optimum pH and temperature for the catalytic activity of the enzyme were about 10.1 and 70°C, respectively. No activity was lost at temperatures up to 65°C in the presence of 5 mM l-lysine. The enzyme was relatively selective for l-lysine as the electron donor, and either NAD or NADP could serve as the electron acceptor (NADP exhibited about 22% of the activity of NAD). The Km values for l-lysine, NAD, and NADP at 50°C and pH 10.0 were 0.73, 0.088, and 0.48 mM, respectively. When the gene encoding this LysDH was cloned and overexpressed in Escherichia coli, a crude extract of the recombinant cells had about 800-fold-higher enzyme activity than the extract of G. stearothermophilus. The nucleotide sequence of the LysDH gene encoded a peptide containing 385 amino acids with a calculated molecular mass of 42,239 Da. PMID:14766574

The level of glucose-6-phosphate dehydrogenase activity strongly influences xylose fermentation and inhibitor sensitivity in recombinant Saccharomyces cerevisiae strains

DEFF Research Database (Denmark)

Jeppsson, M.; Johansson, B.; Jensen, Peter Ruhdal

2003-01-01

production levels of G6PDH on xylose fermentation. We used a synthetic promoter library and the copper-regulated CUP1 promoter to generate G6PDH-activities between 0% and 179% of the wildtype level. G6PDH-activities of 1% and 6% of the wild-type level resulted in 2.8- and 5.1-fold increase in specific xylose...

Incorporation of 14C glucose into glycogen and glucose-6-phosphate dehydrogenase activity in rat brain following carbon monoxide intoxication

International Nuclear Information System (INIS)

Sikorska, M.; Gorzkowski, B.; Szumanska, G.; Smialek, M.

1975-01-01

Incorporation of 14 C glucose into glycogen and glucose-6-phosphate dehydrogenase activity in rat brain following carbon monoxide intoxication was studied. In brains of rats tested on the 20, 30 and 60th minute of exposure to CO and immediately after removal from the chamber the enzyme activity showed no essential deviation from the control level. In the group of rats tested 1 hour after taking them out from the chamber increase of the enzyme activity was noticed, amounting to about 33% of the control value. The brains tested 24 hours after exposure showed the largest increase of the enzyme activity by about 94%. In the next time periods, 48 and 72 hours after intoxication, the enzyme activity was decreasing. The glycogen content in brains of control animals increased 3 hours after CO intoxication by about 69%. The increase of glycogen synthesis was expressed by increase of the total radioactivity, which amounted to 160% of the control value. (Z.M.)

INFLUENCE OF pH, TEMPERATURE AND DISSOLVED OXYGEN CONCENTRATION ON THE PRODUCTION OF GLUCOSE 6-PHOSPHATE DEHYDROGENASE AND INVERTASE BY Saccharomyces cerevisiae

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J. Abrahão-Neto

1997-03-01

Full Text Available The effect of pH (from 4.0 to 5.0, temperature (T (from 30 oC to 40 oC and dissolved oxygen concentration (DO (from 0.2 to 6.0 mg O2/L on glucose 6-phosphate dehydrogenase (G6PDH (EC 1.1.1.49 and Invertase (EC 3.2.1.26 formation by S. cerevisiae were studied. The best culture conditions for G6PDH and Invertase formation were: 2.55 L culture medium (yeast extract, 3.0 g/L; 5peptone, 5.0 g/L; glucose, 2.0 g/L; sucrose, 15.0 g/L; Na2HPO4.12 H2O, 2.4 g/L; (NH42SO4, 5.1 g/L and MgSO4. 7H2O, 0.075 g/L; 0.45 L inoculum (0.70 g dry cell/L; pH = 4.5; T = 35 oC and DO = 4.0 mg/L. G6PDH was highly sensitive to pH, T and DO variation. The increase in G6PDH production was about three times when the DO ranged from 0.2 to 4.0 mg O2/L. Moreover, by shifting pH from 5.0 to 4.5 and temperature from 30 oC to 35 oC, G6PDH formation increased by 57% and 70%, respectively. Invertase activity (IA of whole cells decreased at least 50% at extremes values of DO (2.0 and 6.0 mg O2/L and pH (4.0 and 5.0. Furthermore, IA oscillated during the fermentation due to the glucose repression/derepression mechanism

Inhibition of the pentose phosphate shunt by 2,3-diphosphoglycerate in erythrocyte pyruvate kinase deficiency.

Science.gov (United States)

Tomoda, A; Lachant, N A; Noble, N A; Tanaka, K R

1983-07-01

Pentose phosphate shunt activity was studied by the release of 14CO2 from 14C-1-glucose and 14C-2-glucose in the red cells of five patients with pyruvate kinase deficiency and found to be significantly decreased after new methylene blue stimulation when compared to high reticulocyte controls. Incubated Heinz body formation was increased and the ascorbate cyanide test was positive in blood from these patients. The activity of glucose-6-phosphate dehydrogenase (G6PD) as well as that of 6-phosphogluconate dehydrogenase (6PGD) was inhibited to 20% of baseline in normal red cell haemolysate by 4 mM 2,3-diphosphoglycerate at pH 7.1. 2,3-Diphosphoglycerate was a competitive inhibitor with 6-phosphogluconate (Ki=1.05 mM) and a noncompetitive inhibitor with NADP (Ki=3.3 mM) for 6PGD. Since the intracellular concentrations of glucose-6-phosphate, 6-phosphogluconate and NADP are below their Kms for G6PD and 6PGD, the kinetic data suggest that increased concentrations of 2,3-diphosphoglycerate in pyruvate kinase deficient red cells are sufficiently high to suppress pentose phosphate shunt activity. This suppression may be an additional factor contributing to the haemolytic anaemia of pyruvate kinase deficiency, particularly during periods of infection or metabolic stress.

[Intensity of pentose phosphate metabolism of carbohydrates in various brain areas in normal and starved animals].

Science.gov (United States)

Kerimov, B F

2002-01-01

The activities of key enzymes of pentose phosphate pathway, glucose-6-phosphate dehydrogenase (G-6 PD) and 6-phosphogluconate dehydrogenase (6-PGD), were studied in cytoplasmatic fractions of brain cortical (limbic, orbital, sensorimotor cortex) and subcortical (myelencefalon, mesencefalon, hypothalamus) structures of rats subjected to starvation for 1, 2, 3, 5 and 7 days. Short-term starvation (1-3 days) caused activation of 6-GPD and 6-PGD both in cortical and subcortical structures. Long-term starvation for 5-7 days caused a decrease of activities of the pentose phosphate pathway enzymes in all studied structures. It is suggested that enzymes of pentose phosphate pathway in nervous tissues are functionally and metabolically related to glutathione system and during starvation they indirectly participate in the regulation lipid peroxidation processes.

Differential induction of enzymes and genes involved in lipid metabolism in liver and visceral adipose tissue of juvenile yellow catfish Pelteobagrus fulvidraco exposed to copper

International Nuclear Information System (INIS)

Chen, Qi-Liang; Luo, Zhi; Pan, Ya-Xiong; Zheng, Jia-Lang; Zhu, Qing-Ling; Sun, Lin-Dan; Zhuo, Mei-Qin; Hu, Wei

2013-01-01

Highlights: •Cu downregulates lipogenesis and reduces lipid deposition in liver and adipose tissue. •Mechanism of Cu affecting lipid metabolism is determined at the enzymatic and molecular levels. •Cu exposure differentially influences lipid metabolism between liver and adipose tissue. -- Abstract: The present study was conducted to determine the mechanism of waterborne Cu exposure influencing lipid metabolism in liver and visceral adipose tissue (VAT) of juvenile yellow catfish Pelteobagrus fulvidraco. Yellow catfish were exposed to four waterborne copper (Cu) concentrations (2 (control), 24 (low), 71 (medium), 198 (high) μg Cu/l, respectively) for 6 weeks. Waterborne Cu exposure had a negative effect on growth and several condition indices (condition factor, viscerosomatic index, hepatosomatic index and visceral adipose index). In liver, lipid content, activities of lipogenic enzymes (6-phosphogluconate dehydrogenase (6PGD), glucose-6-phosphate dehydrogenase (G6PD), malic enzyme (ME), isocitrate dehydrogenase (ICDH), and fatty acid synthase (FAS)) as well as mRNA levels of 6PGD, G6PD, FAS and sterol-regulator element-binding protein-1 (SREBP-1) genes decreased with increasing Cu concentrations. However, activity and mRNA level of lipoprotein lipase (LPL) gene in liver increased. In VAT, G6PD, ME and LPL activities as well as the mRNA levels of FAS, LPL and PPARγ genes decreased in fish exposed to higher Cu concentrations. The differential Pearson correlations between transcription factors (SREBP-1 and peroxisome proliferators-activated receptor-γ (PPARγ)), and the activities and mRNA expression of lipogenic enzymes and their genes were observed between liver and VAT. Thus, our study indicated that reduced lipid contents in liver and VAT after Cu exposure were attributable to the reduced activities and mRNA expression of lipogenic enzymes and their genes in these tissues. Different response patterns of several tested enzymes and genes to waterborne Cu

Differential induction of enzymes and genes involved in lipid metabolism in liver and visceral adipose tissue of juvenile yellow catfish Pelteobagrus fulvidraco exposed to copper

Energy Technology Data Exchange (ETDEWEB)

Chen, Qi-Liang; Luo, Zhi, E-mail: luozhi99@yahoo.com.cn; Pan, Ya-Xiong; Zheng, Jia-Lang; Zhu, Qing-Ling; Sun, Lin-Dan; Zhuo, Mei-Qin; Hu, Wei

2013-07-15

Highlights: •Cu downregulates lipogenesis and reduces lipid deposition in liver and adipose tissue. •Mechanism of Cu affecting lipid metabolism is determined at the enzymatic and molecular levels. •Cu exposure differentially influences lipid metabolism between liver and adipose tissue. -- Abstract: The present study was conducted to determine the mechanism of waterborne Cu exposure influencing lipid metabolism in liver and visceral adipose tissue (VAT) of juvenile yellow catfish Pelteobagrus fulvidraco. Yellow catfish were exposed to four waterborne copper (Cu) concentrations (2 (control), 24 (low), 71 (medium), 198 (high) μg Cu/l, respectively) for 6 weeks. Waterborne Cu exposure had a negative effect on growth and several condition indices (condition factor, viscerosomatic index, hepatosomatic index and visceral adipose index). In liver, lipid content, activities of lipogenic enzymes (6-phosphogluconate dehydrogenase (6PGD), glucose-6-phosphate dehydrogenase (G6PD), malic enzyme (ME), isocitrate dehydrogenase (ICDH), and fatty acid synthase (FAS)) as well as mRNA levels of 6PGD, G6PD, FAS and sterol-regulator element-binding protein-1 (SREBP-1) genes decreased with increasing Cu concentrations. However, activity and mRNA level of lipoprotein lipase (LPL) gene in liver increased. In VAT, G6PD, ME and LPL activities as well as the mRNA levels of FAS, LPL and PPARγ genes decreased in fish exposed to higher Cu concentrations. The differential Pearson correlations between transcription factors (SREBP-1 and peroxisome proliferators-activated receptor-γ (PPARγ)), and the activities and mRNA expression of lipogenic enzymes and their genes were observed between liver and VAT. Thus, our study indicated that reduced lipid contents in liver and VAT after Cu exposure were attributable to the reduced activities and mRNA expression of lipogenic enzymes and their genes in these tissues. Different response patterns of several tested enzymes and genes to waterborne Cu

21 CFR 864.7360 - Erythrocytic glucose-6-phosphate dehydrogenase assay.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Erythrocytic glucose-6-phosphate dehydrogenase assay. 864.7360 Section 864.7360 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages...

17 beta-hydroxysteroid dehydrogenase activity in canine pancreas

International Nuclear Information System (INIS)

Mendoza-Hernandez, G.; Lopez-Solache, I.; Rendon, J.L.; Diaz-Sanchez, V.; Diaz-Zagoya, J.C.

1988-01-01

The mitochondrial fraction of the dog pancreas showed NAD(H)-dependent enzyme activity of 17 beta-hydroxysteroid dehydrogenase. The enzyme catalyzes oxidoreduction between androstenedione and testosterone. The apparent Km value of the enzyme for androstenedione was 9.5 +/- 0.9 microM, the apparent Vmax was determined as 0.4 nmol mg-1 min-1, and the optimal pH was 6.5. In phosphate buffer, pH 7.0, maximal rate of androstenedione reduction was observed at 37 degrees C. The oxidation of testosterone by the enzyme proceeded at the same rate as the reduction of the androstenedione at a pH of 6.8-7.0. The apparent Km value and the optimal pH of the enzyme for testosterone were 3.5 +/- 0.5 microM and 7.5, respectively

Synthesis of bimetallic Pt-Pd core-shell nanocrystals and their high electrocatalytic activity modulated by Pd shell thickness

Science.gov (United States)

Li, Yujing; Wang, Zhi Wei; Chiu, Chin-Yi; Ruan, Lingyan; Yang, Wenbing; Yang, Yang; Palmer, Richard E.; Huang, Yu

2012-01-01

Bimetallic Pt-Pd core-shell nanocrystals (NCs) are synthesized through a two-step process with controlled Pd thickness from sub-monolayer to multiple atomic layers. The oxygen reduction reaction (ORR) catalytic activity and methanol oxidation reactivity of the core-shell NCs for fuel cell applications in alkaline solution are systematically studied and compared based on different Pd thickness. It is found that the Pd shell helps to reduce the over-potential of ORR by up to 50mV when compared to commercial Pd black, while generating up to 3-fold higher kinetic current density. The carbon monoxide poisoning test shows that the bimetallic NCs are more resistant to the CO poisoning than Pt NCs and Pt black. It is also demonstrated that the bimetallic Pt-Pd core-shell NCs can enhance the current density of the methanol oxidation reaction, lowering the over-potential by 35 mV with respect to the Pt core NCs. Further investigation reveals that the Pd/Pt ratio of 1/3, which corresponds to nearly monolayer Pd deposition on Pt core NCs, gives the highest oxidation current density and lowest over-potential. This study shows for the first time the systematic investigation of effects of Pd atomic shells on Pt-Pd bimetallic nanocatalysts, providing valuable guidelines for designing high-performance catalysts for fuel cell applications.Bimetallic Pt-Pd core-shell nanocrystals (NCs) are synthesized through a two-step process with controlled Pd thickness from sub-monolayer to multiple atomic layers. The oxygen reduction reaction (ORR) catalytic activity and methanol oxidation reactivity of the core-shell NCs for fuel cell applications in alkaline solution are systematically studied and compared based on different Pd thickness. It is found that the Pd shell helps to reduce the over-potential of ORR by up to 50mV when compared to commercial Pd black, while generating up to 3-fold higher kinetic current density. The carbon monoxide poisoning test shows that the bimetallic NCs are more

Purification of 6-phosphogluconate dehydrogenase from parsley (Petroselinum hortense) leaves and investigation of some kinetic properties.

Science.gov (United States)

Demir, Hülya; Ciftçi, Mehmet; Küfrevioğlu, O Irfan

2003-02-01

In this study, 6-phosphogluconate dehydrogenase (E.C.1.1.44; 6PGD) was purified from parsley (Petroselinum hortense) leaves, and analysis of the kinetic behavior and some properties of the enzyme were investigated. The purification consisted of three steps that are preparation of homogenate ammonium sulfate fractionation and on DEAE-Sephadex A50 ion exchange. The enzyme was obtained with a yield of 49% and had a specific activity of 18.3 U (mg proteins)(-1) (Lehninger, A.L.; Nelson, D.L.; Cox, M.M. Principles of Biochemistry, 2nd Ed.; Worth Publishers Inc.: N.Y., 2000, 558-560). The overall purification was about 339-fold. A temperature of +4 degrees C was maintained during the purification process. Enzyme activity was spectrophotometrically measured according to the Beutler method at 340 mn. In order to control the purification of the enzyme, SDS-polyacrylamide gel electrophoresis was carried out in 4% and 10% acrylamide for stacking and running gel, respectively. SDS-polyacrylamide gel electrophoresis showed a single band for enzyme. The molecular weight was found to be 97.5 kDa by Sephadex G-150 gel filtration chromatography. A protein band corresponding to a subunit molecular weight of 24.1 kDa was obtained on SDS-polyacrylamide gel electrophoresis. For the enzymes, the stable pH, optimum pH, and optimum temperature were found as 8.0, 8.0, and 50 degrees C, respectively. In addition, KM and Vmax values for NADP+ and G6-P at optimum pH and 25 degrees C were determined by means of Lineweaver-Burk plots.

Effects of sh-reagents on rat hepatic aldehyde dehydrogenase activity

Energy Technology Data Exchange (ETDEWEB)

Konoplitskaya, K.L.; Kuz' mina, G.I.; Grigor' yeva, M.V.; Poznyakova, T.N.

The liver serves as the primary organ for the oxidation of ingested ethanol via a pathway involving alcohol- and aldehyde dehydrogenase. In view of the problem of alcoholism, three enzymes are of particular interest in understanding the biochemical mechanism that may be involved in alcohol addiction and in the formulation of therapeutic approaches. While alcohol dehydrogenase has been studied in considerable detail, current attention is centered on aldehyde dehydrogenase. A comparative analysis of the effects of a series of SH-active reagents - tetraethylthiuram disulfide (TETD), 5,5-dithiobisnitrobenzoic acid (DTNB), p-chloromercurybenzoate (PCMB), and N-ethylmaleimide (NEM) - were tested for their effects on the activity of aldehyde dehydrogenase of the hepatic mitochondrial (isozymes I and II) and microsomal (isozyme II) fractions of outbred albino rats. DTNB was found to be inhibited by 100 and 50% mitochondrial isozymes I and II, respectively, and by 20%, the microsomal enzyme under the conditions employed. DTNB and NEM inhibited by 30 and 50% isozymes I and II of the mitochondria, but had no effect on the microsomal isozyme. 24 references, 3 figures.

Exercise-induced pyruvate dehydrogenase activation is not affected by 7 days of bed rest

DEFF Research Database (Denmark)

Kiilerich, Kristian; Jørgensen, Stine Ringholm; Biensø, Rasmus Sjørup

2011-01-01

To test the hypothesis that physical inactivity impairs the exercise-induced modulation of pyruvate dehydrogenase (PDH), 6 healthy normally physically active male subjects completed 7 days of bed rest. Before and immediately after the bed rest, the subjects completed an OGTT and a one-legged knee...

`Pd20Sn13' revisited: crystal structure of Pd6.69Sn4.31

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Wilhelm Klein

2015-07-01

Full Text Available The crystal structure of the title compound was previously reported with composition `Pd20Sn13' [Sarah et al. (1981. Z. Metallkd, 72, 517–520]. For the original structure model, as determined from powder X-ray data, atomic coordinates from the isostructural compound Ni13Ga3Ge6 were transferred. The present structure determination, resulting in a composition Pd6.69Sn4.31, is based on single crystal X-ray data and includes anisotropic displacement parameters for all atoms as well as standard uncertainties for the atomic coordinates, leading to higher precision and accuracy for the structure model. Single crystals of the title compound were obtained via a solid-state reaction route, starting from the elements. The crystal structure can be derived from the AlB2 type of structure after removing one eighth of the atoms at the boron positions and shifting adjacent atoms in the same layer in the direction of the voids. One atomic site is partially occupied by both elements with a Pd:Sn ratio of 0.38 (3:0.62 (3. One Sn and three Pd atoms are located on special positions with site symmetry 2. (Wyckoff letter 3a and 3b.

Effect of different mulch materials on the soil dehydrogenase activity (DHA) in an organic pepper crop

Science.gov (United States)

Moreno, Marta M.; Peco, Jesús; Campos, Juan; Villena, Jaime; González, Sara; Moreno, Carmen

2016-04-01

The use biodegradable materials (biopolymers of different composition and papers) as an alternative to conventional mulches has increased considerably during the last years mainly for environmental reason. In order to assess the effect of these materials on the soil microbial activity during the season of a pepper crop organically grown in Central Spain, the soil dehydrogenase activity (DHA) was measured in laboratory. The mulch materials tested were: 1) black polyethylene (PE, 15 μm); black biopolymers (15 μm): 2) Mater-Bi® (corn starch based), 3) Sphere 4® (potato starch based), 4) Sphere 6® (potato starch based), 5) Bioflex® (polylactic acid based), 6) Ecovio® (polylactic acid based), 7) Mimgreen® (black paper, 85 g/m2). A randomized complete block design with four replications was adopted. The crop was drip irrigated following the water demand of each treatment. Soil samples (5-10 cm depth) under the different mulches were taken at different dates (at the beginning of the crop cycle and at different dates throughout the crop season). Additionally, samples of bare soil in a manual weeding and in an untreated control were taken. The results obtained show the negative effect of black PE on the DHA activity, mainly as result of the higher temperature reached under the mulch and the reduction in the gas interchange between the soil and the atmosphere. The values corresponding to the biodegradable materials were variable, although highlighting the low DHA activity observed under Bioflex®. In general, the uncovered treatments showed higher values than those reached under mulches, especially in the untreated control. Keywords: mulch, biodegradable, biopolymer, paper, dehydrogenase activity (DHA). Acknowledgements: the research was funded by Project RTA2011-00104-C04-03 from the INIA (Spanish Ministry of Economy and Competitiveness).

Inhibition of catalase by aminotriazole in vivo results in reduction of glucose-6-phosphate dehydrogenase activity in Saccharomyces cerevisiae cells.

Science.gov (United States)

Bayliak, M; Gospodaryov, D; Semchyshyn, H; Lushchak, V

2008-04-01

The inhibitor of catalase 3-amino-1,2,4-triazole (AMT) was used to study the physiological role of catalase in the yeast Saccharomyces cerevisiae under starvation. It was shown that AMT at the concentration of 10 mM did not affect the growth of the yeast. In vivo and in vitro the degree of catalase inhibition by AMT was concentration- and time-dependent. Peroxisomal catalase in bakers' yeast was more sensitive to AMT than the cytosolic one. In vivo inhibition of catalase by AMT in S. cerevisiae caused a simultaneous decrease in glucose-6-phosphate dehydrogenase activity and an increase in glutathione reductase activity. At the same time, the level of protein carbonyls, a marker of oxidative modification, was not affected. Possible mechanisms compensating the negative effects caused by AMT inhibition of catalase are discussed.

Incorporation of /sup 14/C glucose into glycogen and glucose-6-phosphate dehydrogenase activity in rat brain following carbon monoxide intoxication

Energy Technology Data Exchange (ETDEWEB)

Sikorska, M; Gorzkowski, B; Szumanska, G; Smialek, M [Polska Akademia Nauk, Warsaw. Centrum Medycyny Doswiadczalnej i Klinicznej; Panstwowy Zaklad Higieny, Warsaw (Poland))

1975-01-01

Incorporation of /sup 14/C glucose into glycogen and glucose-6-phosphate dehydrogenase activity in rat brain following carbon monoxide intoxication was studied. In brains of rats tested on the 20, 30 and 60th minute of exposure to CO and immediately after removal from the chamber the enzyme activity showed no essential deviation from the control level. In the group of rats tested 1 hour after taking them out from the chamber increase of the enzyme activity was noticed, amounting to about 33% of the control value. The brains tested 24 hours after exposure showed the largest increase of the enzyme activity by about 94%. In the next time periods, 48 and 72 hours after intoxication, the enzyme activity was decreasing. The glycogen content in brains of control animals increased 3 hours after CO intoxication by about 69%. The increase of glycogen synthesis was expressed by increase of the total radioactivity, which amounted to 160% of the control value.

Characterization of human short chain dehydrogenase/reductase SDR16C family members related to retinol dehydrogenase 10.

Science.gov (United States)

Adams, Mark K; Lee, Seung-Ah; Belyaeva, Olga V; Wu, Lizhi; Kedishvili, Natalia Y

2017-10-01

All-trans-retinoic acid (RA) is a bioactive derivative of vitamin A that serves as an activating ligand for nuclear transcription factors, retinoic acid receptors. RA biosynthesis is initiated by the enzymes that oxidize retinol to retinaldehyde. It is well established that retinol dehydrogenase 10 (RDH10, SDR16C4), which belongs to the 16C family of the short chain dehydrogenase/reductase (SDR) superfamily of proteins, is the major enzyme responsible for the oxidation of retinol to retinaldehyde for RA biosynthesis during embryogenesis. However, several lines of evidence point towards the existence of additional retinol dehydrogenases that contribute to RA biosynthesis in vivo. In close proximity to RDH10 gene on human chromosome 8 are located two genes that are phylogenetically related to RDH10. The predicted protein products of these genes, retinol dehydrogenase epidermal 2 (RDHE2, SDR16C5) and retinol dehydrogenase epidermal 2-similar (RDHE2S, SDR16C6), share 59% and 56% sequence similarity with RDH10, respectively. Previously, we showed that the single ortholog of the human RDHE2 and RDHE2S in frogs, Xenopus laevis rdhe2, oxidizes retinol to retinaldehyde and is essential for frog embryonic development. In this study, we explored the potential of each of the two human proteins to contribute to RA biosynthesis. The results of this study demonstrate that human RDHE2 exhibits a relatively low but reproducible activity when expressed in either HepG2 or HEK293 cells. Expression of the native RDHE2 is downregulated in the presence of elevated levels of RA. On the other hand, the protein encoded by the human RDHE2S gene is unstable when expressed in HEK293 cells. RDHE2S protein produced in Sf9 cells is stable but has no detectable catalytic activity towards retinol. We conclude that the human RDHE2S does not contribute to RA biosynthesis, whereas the low-activity RA-sensitive human RDHE2 may have a role in adjusting the cellular levels of RA in accord with

Analyses of the peripheral immunome following multiple administrations of avelumab, a human IgG1 anti-PD-L1 monoclonal antibody

OpenAIRE

Donahue, Renee N.; Lepone, Lauren M.; Grenga, Italia; Jochems, Caroline; Fantini, Massimo; Madan, Ravi A.; Heery, Christopher R.; Gulley, James L.; Schlom, Jeffrey

2017-01-01

Background Multiple anti-PD-L1/PD-1 checkpoint monoclonal antibodies (MAb) have shown clear evidence of clinical benefit. All except one have been designed or engineered to omit the possibility to mediate antibody-dependent cell-mediated cytotoxicity (ADCC) as a second potential mode of anti-tumor activity; the reason for this is the concern of lysis of PD-L1 positive immune cells. Avelumab is a fully human IgG1 MAb which has been shown in prior in vitro studies to mediate ADCC versus a range...

Phase transformations in the Cu.6 Pd.4 alloy

International Nuclear Information System (INIS)

Imakuma, K.

1977-01-01

Order-disorder and structural transformations in the Cu-Pd 60-40% (Cu. 6 Pd. 4 ) alloy by means of a temperature and time dependent treatment are studied. The structural transformations by x-rays diffraction are also studied, where the bcc, fcc and tetragonal phases were observed. A qualitative analyze of the resistivity kinetics are made [pt

The Diagnostic Significance of Serum Alcohol Dehydrogenase Isoenzymes and Aldehyde Dehydrogenase Activity in Urinary Bladder Cancer Patients.

Science.gov (United States)

Orywal, Karolina; Jelski, Wojciech; Werel, Tadeusz; Szmitkowski, Maciej

2017-07-01

The aim of this study was to investigate a potential role of alcohol dehydrogenase and aldehyde dehydrogenase as tumor markers for urinary bladder cancer. Serum samples were obtained from 41 patients with bladder cancer and 52 healthy individuals. Class III and IV of ADH and total ADH activity were measured by the photometric method. For measurement of class I and II ADH and ALDH activity, the fluorometric method was employed. Significantly higher total activity of ADH was found in sera of both, low-grade and high-grade bladder cancer patients. The diagnostic sensitivity for total ADH activity was 81.5%, specificity 98.1%, positive (PPV) and negative (NPV) predictive values were 97.4% and 92.3% respectively. Area under ROC curve for total ADH activity was 0.848. A potential role of total ADH activity as a marker for bladder cancer, is herein proposed. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Reductive dechlorination of {gamma}-hexachlorocyclohexane using Fe-Pd bimetallic nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Nagpal, Varima; Bokare, Alok D. [Center for Nanobioscience, Agharkar Research Institute, G.G. Agarkar Road, Pune 411004, Maharashtra (India); Chikate, Rajeev C. [Department of Chemistry, MES Abasaheb Garware College, Karve Road, Pune 411004 (India); Rode, Chandrashekhar V. [Chemical Engineering and Process Development Division, National Chemical Laboratory, Pune 411008 (India); Paknikar, Kishore M., E-mail: paknikar@vsnl.com [Center for Nanobioscience, Agharkar Research Institute, G.G. Agarkar Road, Pune 411004, Maharashtra (India)

2010-03-15

Nanoscale Fe-Pd bimetallic particles were synthesized and used for degradation of lindane ({gamma}-hexachlorocyclohexane) in aqueous solution. Batch studies showed that 5 mg/L of lindane was completely dechlorinated within 5 min at a catalyst loading of 0.5 g/L and the degradation process followed first-order kinetics. GC-MS analysis in corroboration with GC-ECD results showed the presence of cyclohexane as the final degradation product. The proposed mechanism for the reductive dechlorination of lindane involves Fe corrosion-induced hydrogen atom transfer from the Pd surface. The enhanced degradation efficiency of Fe-Pd nanoparticles is attributed to: (1) high specific surface area of the nanoscale metal particles (60 m{sup 2}/g), manyfold greater that of commercial grade micro- or milli-scale iron particles ({approx}1.6 m{sup 2}/g); and, (2) increased catalytic reactivity due to the presence of Pd on the surface. Recycling and column studies showed that these nanoparticles exhibit efficient and sustained catalytic activity.

Phrenic and hypoglossal nerve activity during respiratory response to hypoxia in 6-OHDA unilateral model of Parkinson's disease.

Science.gov (United States)

Andrzejewski, Kryspin; Budzińska, Krystyna; Kaczyńska, Katarzyna

2017-07-01

Parkinson's disease (PD) patients apart from motor dysfunctions exhibit respiratory disturbances. Their mechanism is still unknown and requires investigation. Our research was designed to examine the activity of phrenic (PHR) and hypoglossal (HG) nerves activity during a hypoxic respiratory response in the 6-hydroxydopamine (6-OHDA) model of PD. Male adult Wistar rats were injected unilaterally with 6-OHDA (20μg) or the vehicle into the right medial forebrain bundle (MFB). Two weeks after the surgery the activity of the phrenic and hypoglossal nerve was registered in anesthetized, vagotomized, paralyzed, and mechanically ventilated rats under normoxic and hypoxic conditions. Lesion effectiveness was confirmed by the cylinder test, performed before the MFB injection and 14days after, before the respiratory experiment. 6-OHDA lesioned animals showed a significant increase in normoxic inspiratory time. Expiratory time and total time of the respiratory cycle were prolonged in PD rats after hypoxia. The amplitude of the PHR activity and its minute activity were increased in comparison to the sham group at recovery time and during 30s of hypoxia. The amplitude of the HG activity was increased in response to hypoxia in 6-OHDA lesioned animals. The degeneration of dopaminergic neurons decreased the pre-inspiratory/inspiratory ratio of the hypoglossal burst amplitude during and after hypoxia. Unilateral MFB lesion changed the activity of the phrenic and hypoglossal nerves. The altered pre-inspiratory hypoglossal nerve activity indicates modifications to the central mechanisms controlling the activity of the HG nerve and may explain respiratory disorders seen in PD, i.e. apnea. Copyright © 2017 Elsevier Inc. All rights reserved.

Burden of Hemoglobinopathies (Thalassemia, Sickle Cell Disorders and G6PD Deficiency) in Iran, 1990-2010: findings from the Global Burden of Disease Study 2010.

Science.gov (United States)

Rezaei, Nazila; Naderimagham, Shohreh; Ghasemian, Anoosheh; Saeedi Moghaddam, Sahar; Gohari, Kimia; Zareiy, Saeid; Sobhani, Sahar; Modirian, Mitra; Kompani, Farzad

2015-08-01

Hemoglobinopathies are known as the most common genetic disorders in Iran. The paper aims to provide global estimates of deaths and disability adjusted life years (DALYs) due to hemoglobinopathies in Iran by sex and age during 1990 to 2010 and describe the challenges due to limitations of the Global Burden of Disease Study 2010 (GBD 2010). GBD 2010 estimates of the numbers of deaths and years of life lost (YLLs) due to premature mortality were calculated using the Cause of Death Ensemble model (CODEm). Years of life lost due to disability (YLDs) were computed by multiplication of prevalence, the disability weight for occurrence of sequelae, and the duration of symptoms. Prevalence was estimated through a systematic search of published and available unpublished data sources, with a Bayesian meta-regression model developed for GBD 2010. Disability weights were produced using collected data from population-based surveys. Uncertainty from all inputs was incorporated into the computations of DALYs using simulation methods. We aim to prepare and criticize the results of GBD 2010 and provide some recommendations for reaching better conclusions about the burden of hemoglobinopathies in Iran. Between 1990 and 2010, the overall deaths attributed to hemoglobinopathies decreased from 0.51% to 0.36% of total deaths, with the corresponding burden declining from 1% to 0.82% of total DALYs. There was a reduction in deaths and DALYs rates for all ages and the rates attributed to all ages followed the same pattern in Iranian men and women. The highest DALYs for hemoglobinopathies, thalassemia, sickle cell disorder, and glucose-6-phosphate dehydrogenase deficiency (G6PD-D) were found in those aged less than 5 years. The collective burden of all of these hemoglobin disorder was lower in 2010 than in 1990. Although the screening programs in Iran have been very successful in reducing the number of thalassemia patients between 1990 to 2010, in order to provide a better estimation of the

Proteomic strategy for the analysis of the polychlorobiphenyl-degrading cyanobacterium Anabaena PD-1 exposed to Aroclor 1254.

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Hangjun Zhang

Full Text Available The cyanobacterium Anabaena PD-1, which was originally isolated from polychlorobiphenyl (PCB-contaminated paddy soils, has capabilities for dechlorinatin and for degrading the commercial PCB mixture Aroclor 1254. In this study, 25 upregulated proteins were identified using 2D electrophoresis (2-DE coupled with matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS. These proteins were involved in (i PCB degradation (i.e., 3-chlorobenzoate-3,4-dioxygenase; (ii transport processes [e.g., ATP-binding cassette (ABC transporter substrate-binding protein, amino acid ABC transporter substrate-binding protein, peptide ABC transporter substrate-binding protein, putrescine-binding protein, periplasmic solute-binding protein, branched-chain amino acid uptake periplasmic solute-binding protein, periplasmic phosphate-binding protein, phosphonate ABC transporter substrate-binding protein, and xylose ABC transporter substrate-binding protein]; (iii energetic metabolism (e.g., methanol/ethanol family pyrroloquinoline quinone (PQQ-dependent dehydrogenase, malate-CoA ligase subunit beta, enolase, ATP synthase β subunit, FOF1 ATP synthase subunit beta, ATP synthase α subunit, and IMP cyclohydrolase; (iv electron transport (cytochrome b6f complex Fe-S protein; (v general stress response (e.g., molecular chaperone DnaK, elongation factor G, and translation elongation factor thermostable; (vi carbon metabolism (methanol dehydrogenase and malate-CoA ligase subunit beta; and (vii nitrogen reductase (nitrous oxide reductase. The results of real-time polymerase chain reaction showed that the genes encoding for dioxygenase, ABC transporters, transmembrane proteins, electron transporter, and energetic metabolism proteins were significantly upregulated during PCB degradation. These genes upregulated by 1.26- to 8.98-fold. These findings reveal the resistance and adaptation of cyanobacterium to the presence of PCBs, shedding light on the

Inhibition of dehydrogenase activity in petroleum refinery wastewater bacteria by phenolic compounds

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Gideon C. Okpokwasili

2010-04-01

Full Text Available The toxicity of phenol, 2-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol, 2-chlorophenol, 4-chlorophenol, 4-bromophenol and 3,5-dimethylphenol on Pseudomonas, Bacillus and Escherichia species isolated from petroleum refinery wastewater was assessed via inhibition of dehydrogenase enzyme activity. At low concentrations, 2-nitrophenol, 2-chlorophenol, 4-chlorophenol, 4-bromophenol and 3,5-dimethylphenol stimulated dehydrogenase activity and at sufficient concentrations, phenolic compounds inhibited dehydrogenase activities. Generally, phenol is less toxic than substituted phenols. Estimations of the degree of inhibition/stimulation of dehydrogenase activities showed significant dose-dependent responses that are describable by logistic functions. The toxicity thresholds varied significantly (P < 0.05 among the bacterial strains and phenolic compounds. The median inhibitory concentrations (IC50s ranged from 4.118 ± 0.097 mg.L-1 for 4-nitrophenol against Pseudomonas sp. DAF1 to 1407.997 ± 7.091 mg.L-1 for phenol against Bacillus sp. DISK1. This study suggested that the organisms have moderate sensitivity to phenols and have the potential to be used as indicators for assessment of chemical toxicity. They could also be used as catalysts for degradation of phenols in effluents.

Molecular Characterization of Glucose-6-Phosphate ...

African Journals Online (AJOL)

HP

The total prevalence of G6PD deficiency among the subjects was 4.59 % (4/87), all of whom were. Malay males. One of the deficient subjects had G6PD Viangchan, while the other three were G6PD. Mahidol ..... J Paediatr Child Health .1991 ...

On formation mechanism of Pd-Ir bimetallic nanoparticles through thermal decomposition of [Pd(NH3)4][IrCl6

Science.gov (United States)

Asanova, Tatyana I.; Asanov, Igor P.; Kim, Min-Gyu; Gerasimov, Evgeny Yu.; Zadesenets, Andrey V.; Plyusnin, Pavel E.; Korenev, Sergey V.

2013-10-01

The formation mechanism of Pd-Ir nanoparticles during thermal decomposition of double complex salt [Pd(NH3)4][IrCl6] has been studied by in situ X-ray absorption (XAFS) and photoelectron (XPS) spectroscopies. The changes in the structure of the Pd and Ir closest to the surroundings and chemical states of Pd, Ir, Cl, and N atoms were traced in the range from room temperature to 420 °C in inert atmosphere. It was established that the thermal decomposition process is carried out in 5 steps. The Pd-Ir nanoparticles are formed in pyramidal/rounded Pd-rich (10-200 nm) and dendrite Ir-rich (10-50 nm) solid solutions. A d charge depletion at Ir site and a gain at Pd, as well as the intra-atomic charge redistribution between the outer d and s and p electrons of both Ir and Pd in Pd-Ir nanoparticles, were found to occur.

Inhibition of dehydrogenase activity in petroleum refinery wastewater bacteria by phenolic compounds

OpenAIRE

Gideon C. Okpokwasili; Christian Okechukwu Nweke

2010-01-01

The toxicity of phenol, 2-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol, 2-chlorophenol, 4-chlorophenol, 4-bromophenol and 3,5-dimethylphenol on Pseudomonas, Bacillus and Escherichia species isolated from petroleum refinery wastewater was assessed via inhibition of dehydrogenase enzyme activity. At low concentrations, 2-nitrophenol, 2-chlorophenol, 4-chlorophenol, 4-bromophenol and 3,5-dimethylphenol stimulated dehydrogenase activity and at sufficient concentrations, phenolic compounds inhibi...

Serum creatine kinase and lactate dehydrogenase activities in ...

African Journals Online (AJOL)

... in thyroid function are common endocrine disorders affecting 5-10% of individuals over ... Key words: Hyperthyroidism, hypothyroidism, lactate dehydrogenase, serum creatine kinase ... individuals depends on age, race, lean body mass and physical activity. ... measured by radioimmunoassay on AXSYM System (Abbott.

One-pot synthesis of Pd-Pt@Pd core-shell nanocrystals with enhanced electrocatalytic activity for formic acid oxidation

KAUST Repository

Yuan, Qiang

2014-01-01

Well-defined Pd-Pt@Pd core-shell nanocrystals with a Pd-Pt alloy core and a conformal Pd shell of ~2-3 nm were directly synthesized through a one-pot, aqueous solution approach without any preformed Pd or Pt seeds. These Pd-Pt@Pd core-shell nanocrystals show an enhanced electrocatalytic activity for formic acid oxidation compared with commercial Pd black. This journal is © 2014 The Royal Society of Chemistry.

Highly Active, Carbon-supported, PdSn Nano-core, Partially ...

African Journals Online (AJOL)

Carbon-supported, Pt partially covered, PdSn alloy nanoparticles (Pt-PdSn/C) were synthesized via a metathetical reaction of PdSn alloy nanoparticles, and a platinum precursor. The electrochemical activity was evaluated by methanol oxidation. The Pt-PdSn/C catalysts were characterized by transmission electron ...

High-Throughput Screening of Coenzyme Preference Change of Thermophilic 6-Phosphogluconate Dehydrogenase from NADP(+) to NAD(.).

Science.gov (United States)

Huang, Rui; Chen, Hui; Zhong, Chao; Kim, Jae Eung; Zhang, Yi-Heng Percival

2016-09-02

Coenzyme engineering that changes NAD(P) selectivity of redox enzymes is an important tool in metabolic engineering, synthetic biology, and biocatalysis. Here we developed a high throughput screening method to identify mutants of 6-phosphogluconate dehydrogenase (6PGDH) from a thermophilic bacterium Moorella thermoacetica with reversed coenzyme selectivity from NADP(+) to NAD(+). Colonies of a 6PGDH mutant library growing on the agar plates were treated by heat to minimize the background noise, that is, the deactivation of intracellular dehydrogenases, degradation of inherent NAD(P)H, and disruption of cell membrane. The melted agarose solution containing a redox dye tetranitroblue tetrazolium (TNBT), phenazine methosulfate (PMS), NAD(+), and 6-phosphogluconate was carefully poured on colonies, forming a second semi-solid layer. More active 6PGDH mutants were examined via an enzyme-linked TNBT-PMS colorimetric assay. Positive mutants were recovered by direct extraction of plasmid from dead cell colonies followed by plasmid transformation into E. coli TOP10. By utilizing this double-layer screening method, six positive mutants were obtained from two-round saturation mutagenesis. The best mutant 6PGDH A30D/R31I/T32I exhibited a 4,278-fold reversal of coenzyme selectivity from NADP(+) to NAD(+). This screening method could be widely used to detect numerous redox enzymes, particularly for thermophilic ones, which can generate NAD(P)H reacted with the redox dye TNBT.

Radiation target analyses of free and immobilized glucose 6-phosphate dehydrogenase

International Nuclear Information System (INIS)

Kempner, E.S.; Miller, J.H.

2010-01-01

The sensitivity of the enzyme glucose 6-phosphate dehydrogenase to ionizing radiation was examined under several conditions, including the presence of several free-radical scavengers. The enzyme was also irradiated when covalently bound to polyacrylamide beads whose structure is very similar to the polypeptide backbone of proteins. All the enzyme forms were irradiated in the frozen state with high-energy electrons from a linear accelerator. Surviving enzyme activity and surviving monomers were determined; the data were analyzed by target theory. Free-radical scavengers reduced the radiation target size of both the activity and monomers of the free enzyme, but not that of the immobilized enzyme activity. The target size of the activity of the free enzyme was that of a dimer mass, but in the case of the immobilized enzyme it was equal to the smaller mass of the monomer. Free-radical scavengers reduce the target size by modifying radiation energy transfer. The target size of the polyacrylamide-bound enzyme activity was expected to be very large since the connection between polyacrylamide and protein is a peptide bond which permits transfer of radiation-deposited energy. Several explanations concerning energy transfer are suggested for this result.

Icterícia neonatal e deficiência de glicose-6-fosfato desidrogenase Neonatal jaundice and glucose-6-phosphate dehydrogenase

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Amauri Antiquera Leite

2010-01-01

Full Text Available A deficiência de glicose-6-fosfato desidrogenase em neonatos pode ser a responsável pela icterícia neonatal. Este comentário científico é decorrente do relato sobre o tema publicado neste fascículo e que preocupa diversos autores de outros países em relação às complicações em neonatos de hiperbilirrubinemia, existindo inclusive proposições de alguns autores em incluir o teste para identificar a deficiência de glicose-6-fosfato desidrogenase nos recém-nascidos.Glucose-6-phosphate dehydrogenase in newborn babies may be responsible for neonatal jaundice. There is a concern of many authors from other countries in respect to complications in neonates with hyperbilirubinemia; some authors even propose screening for glucose-6-phosphate dehydrogenase deficiency in newborn babies. A scientific report on this subject is published in this issue.