The Experts below are selected from a list of 210 Experts worldwide ranked by ideXlab platform
Cindy S Chu - One of the best experts on this subject based on the ideXlab platform.
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evaluation of a novel quantitative test for glucose 6 phosphate Dehydrogenase Deficiency bringing quantitative testing for glucose 6 phosphate Dehydrogenase Deficiency closer to the patient
American Journal of Tropical Medicine and Hygiene, 2019Co-Authors: Sampa Pal, Pooja Bansil, Germana Bancone, Sevan Hrutkay, Maria Kahn, Gornpan Gornsawun, Pimsupah Penpitchaporn, Cindy S ChuAbstract:Glucose-6-Phosphate Dehydrogenase (G6PD) is an essential enzyme that protects red blood cells from oxidative damage caused by certain drugs, diseases, and foods.1,2 The X-linked human G6PD gene is highly polymorphic with many mutations resulting in reduced enzyme activity in red blood cells or G6PD Deficiency. Exposure to oxidative agents can induce hemolysis in red blood cells with low G6PD activity levels and cause severe anemia, sometimes requiring blood transfusion or causing irreversible renal damage and even mortality, if not managed promptly. Glucose-6-Phosphate Dehydrogenase Deficiency presents clinically in the neonate as jaundice resulting from hyperbilirubinemia; this may lead to kernicterus, a form of brain damage.3,4 Several medications including rasburicase- and 8-aminoquinoline–based antimalarial drugs, such as primaquine, are known to cause clinically significant hemolysis in G6PD-deficient individuals. A high of dose primaquine (a 7-or 14-day regimen) is required to cure patients of Plasmodium vivax malaria. If a patient is not cured of P. vivax, they are at risk of relapse with increasing risk of morbidity and further transmission of the parasite.5,6 Relapse contributes to more than 50% of the disease burden in a community.7,8 A single dose of tafenoquine, another 8-aminoquinoline, when given with chloroquine is capable of curing a patient of P. vivax.9 Tafenoquine, recently approved by the United States Food and Drug Administration (FDA) for radical cure of P. vivax, under the Krintafel label, is indicated for individuals with greater than 70% G6PD activity. Tafenoquine has also been approved by the FDA with a different dosage for prophylaxis, under the Arakoda label, with similar indications for G6PD Deficiency. Many countries will struggle to meet their target malaria elimination goals without broader safe access to radical cure of P. vivax. Diagnostic tests that determine a patient’s G6PD status are needed at or near where they seek treatment.10 Glucose-6-Phosphate Dehydrogenase Deficiency is determined by measuring G6PD activity, adjusted for temperature, in blood normalized for either red blood cell count or hemoglobin. Quantitative testing for G6PD is performed in reference or specialized laboratories using a complex assay on a temperature-regulated instrument because of the large temperature impact on enzyme activity. The most commonly used test for clinical screening is the qualitative fluorescent spot test, which accurately discriminates hemizygous-deficient males and homozygous- or heterozygous-deficient females, who typically have G6PD activity less than 30% of normal. Although this is adequate for males who are either deficient ( 80% activity), it is inadequate to classify females who can be G6PD deficient, intermediate (30–80% activity), or normal.11–15 Quantitative point-of-care G6PD tests that can be used in low-resource settings can impact health on many levels, including reductions in neonatal morbidity and mortality. It can also impact health by providing access to safe, radical, curative treatment for P. vivax malaria, which can then prevent relapse burden, onward malaria transmission, and accelerate malaria elimination.7–10,16 Both qualitative and quantitative G6PD Deficiency tests that can be performed closer to the patients are beginning to emerge.17–19 In 2017, the production of a commonly used reference assay for evaluating new G6PD products, the G6PDH quantitative test by Trinity Biotech, was suspended.20 This study presents the results of a bridging evaluation of the Trinity Biotech kit against a commercially available U.S. Food and Drug Administration–cleared reference assay by Pointe Scientific. The innovative, point-of-care STANDARD G6PD test by SD Biosensor was also evaluated against the same reference assay.
Germana Bancone - One of the best experts on this subject based on the ideXlab platform.
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evaluation of a novel quantitative test for glucose 6 phosphate Dehydrogenase Deficiency bringing quantitative testing for glucose 6 phosphate Dehydrogenase Deficiency closer to the patient
American Journal of Tropical Medicine and Hygiene, 2019Co-Authors: Sampa Pal, Pooja Bansil, Germana Bancone, Sevan Hrutkay, Maria Kahn, Gornpan Gornsawun, Pimsupah Penpitchaporn, Cindy S ChuAbstract:Glucose-6-Phosphate Dehydrogenase (G6PD) is an essential enzyme that protects red blood cells from oxidative damage caused by certain drugs, diseases, and foods.1,2 The X-linked human G6PD gene is highly polymorphic with many mutations resulting in reduced enzyme activity in red blood cells or G6PD Deficiency. Exposure to oxidative agents can induce hemolysis in red blood cells with low G6PD activity levels and cause severe anemia, sometimes requiring blood transfusion or causing irreversible renal damage and even mortality, if not managed promptly. Glucose-6-Phosphate Dehydrogenase Deficiency presents clinically in the neonate as jaundice resulting from hyperbilirubinemia; this may lead to kernicterus, a form of brain damage.3,4 Several medications including rasburicase- and 8-aminoquinoline–based antimalarial drugs, such as primaquine, are known to cause clinically significant hemolysis in G6PD-deficient individuals. A high of dose primaquine (a 7-or 14-day regimen) is required to cure patients of Plasmodium vivax malaria. If a patient is not cured of P. vivax, they are at risk of relapse with increasing risk of morbidity and further transmission of the parasite.5,6 Relapse contributes to more than 50% of the disease burden in a community.7,8 A single dose of tafenoquine, another 8-aminoquinoline, when given with chloroquine is capable of curing a patient of P. vivax.9 Tafenoquine, recently approved by the United States Food and Drug Administration (FDA) for radical cure of P. vivax, under the Krintafel label, is indicated for individuals with greater than 70% G6PD activity. Tafenoquine has also been approved by the FDA with a different dosage for prophylaxis, under the Arakoda label, with similar indications for G6PD Deficiency. Many countries will struggle to meet their target malaria elimination goals without broader safe access to radical cure of P. vivax. Diagnostic tests that determine a patient’s G6PD status are needed at or near where they seek treatment.10 Glucose-6-Phosphate Dehydrogenase Deficiency is determined by measuring G6PD activity, adjusted for temperature, in blood normalized for either red blood cell count or hemoglobin. Quantitative testing for G6PD is performed in reference or specialized laboratories using a complex assay on a temperature-regulated instrument because of the large temperature impact on enzyme activity. The most commonly used test for clinical screening is the qualitative fluorescent spot test, which accurately discriminates hemizygous-deficient males and homozygous- or heterozygous-deficient females, who typically have G6PD activity less than 30% of normal. Although this is adequate for males who are either deficient ( 80% activity), it is inadequate to classify females who can be G6PD deficient, intermediate (30–80% activity), or normal.11–15 Quantitative point-of-care G6PD tests that can be used in low-resource settings can impact health on many levels, including reductions in neonatal morbidity and mortality. It can also impact health by providing access to safe, radical, curative treatment for P. vivax malaria, which can then prevent relapse burden, onward malaria transmission, and accelerate malaria elimination.7–10,16 Both qualitative and quantitative G6PD Deficiency tests that can be performed closer to the patients are beginning to emerge.17–19 In 2017, the production of a commonly used reference assay for evaluating new G6PD products, the G6PDH quantitative test by Trinity Biotech, was suspended.20 This study presents the results of a bridging evaluation of the Trinity Biotech kit against a commercially available U.S. Food and Drug Administration–cleared reference assay by Pointe Scientific. The innovative, point-of-care STANDARD G6PD test by SD Biosensor was also evaluated against the same reference assay.
Thomas Wieder - One of the best experts on this subject based on the ideXlab platform.
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enhanced erythrocyte apoptosis in sickle cell anemia thalassemia and glucose 6 phosphate Dehydrogenase Deficiency
Cellular Physiology and Biochemistry, 2002Co-Authors: Karl S Lang, Benjamin Roll, Svetlana Myssina, Markus Schittenhelm, Hansgerhard Scheelwalter, Lothar Kanz, Jasmin Fritz, Florian Lang, Stephan M Huber, Thomas WiederAbstract:Erythrocyte diseases such as sickle cell anemia, thalassemia and Glucose-6-Phosphate Dehydrogenase Deficiency decrease the erythrocyte life span, an effect contributing to anemia. Most recently, erythro-cytes have been shown to undergo apoptosis upon increase of cytosolic Ca(2+) activity. The present study has been performed to explore whether sickle cell anemia, thalassemia and Glucose-6-Phosphate Dehydrogenase Deficiency enhance the sensitivity of erythrocytes to osmotic shock, oxidative stress or energy depletion, all maneuvers known to increase cytosolic Ca(2+) activity. To this end, annexin binding as an indicator of apoptosis has been determined by FACS analysis. Erythrocytes from healthy individuals, from patients with sickle cell anemia, thalassemia or Glucose-6-Phosphate Dehydrogenase Deficiency all responded to osmotic shock (up to 950 mOsm by addition of sucrose for 24 hours), to oxidative stress (up to 1.0 mM tetra-butyl-hydroxyperoxide tBOOH) and to energy depletion (up to 48 hours glucose deprivation) with enhanced annexin binding. However, the sensitivity of sickle cells and of Glucose-6-Phosphate Dehydrogenase deficient cells to osmotic shock and of sickle cells, thalassemic cells and Glucose-6-Phosphate Dehydrogenase deficient cells to oxidative stress and to glucose depletion was significantly higher than that of control cells. Annexin binding was further stimulated by Ca(2+) ionophore ionomycin with significantly higher sensitivity of sickle cells and Glucose-6-Phosphate Dehydrogenase deficient cells as compared to intact cells. In conclusion, sickle cells, thalassemic cells and Glucose-6-Phosphate Dehydrogenase deficient erythrocytes are more sensitive to osmotic shock, oxidative stress and/or energy depletion, thus leading to enhanced apoptosis of those cells. The accelerated apoptosis then contributes to the shortened life span of the defective erythrocytes.
S O Osanyintuyi - One of the best experts on this subject based on the ideXlab platform.
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Glucose-6-Phosphate Dehydrogenase Deficiency in a rural Saudi population.
The Journal of tropical medicine and hygiene, 1991Co-Authors: Tahia H. Saleem, B S Mendis, S O OsanyintuyiAbstract:3291 Saudi male blood donors from a non-malarial area of Saudi Arabia were investigated for their Glucose-6-Phosphate Dehydrogenase levels. The prevalence of Glucose-6-Phosphate Dehydrogenase Deficiency in the Al-Kharj area was 1.91% which is one of the lowest recorded in Saudi Arabia.
Sampa Pal - One of the best experts on this subject based on the ideXlab platform.
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evaluation of a novel quantitative test for glucose 6 phosphate Dehydrogenase Deficiency bringing quantitative testing for glucose 6 phosphate Dehydrogenase Deficiency closer to the patient
American Journal of Tropical Medicine and Hygiene, 2019Co-Authors: Sampa Pal, Pooja Bansil, Germana Bancone, Sevan Hrutkay, Maria Kahn, Gornpan Gornsawun, Pimsupah Penpitchaporn, Cindy S ChuAbstract:Glucose-6-Phosphate Dehydrogenase (G6PD) is an essential enzyme that protects red blood cells from oxidative damage caused by certain drugs, diseases, and foods.1,2 The X-linked human G6PD gene is highly polymorphic with many mutations resulting in reduced enzyme activity in red blood cells or G6PD Deficiency. Exposure to oxidative agents can induce hemolysis in red blood cells with low G6PD activity levels and cause severe anemia, sometimes requiring blood transfusion or causing irreversible renal damage and even mortality, if not managed promptly. Glucose-6-Phosphate Dehydrogenase Deficiency presents clinically in the neonate as jaundice resulting from hyperbilirubinemia; this may lead to kernicterus, a form of brain damage.3,4 Several medications including rasburicase- and 8-aminoquinoline–based antimalarial drugs, such as primaquine, are known to cause clinically significant hemolysis in G6PD-deficient individuals. A high of dose primaquine (a 7-or 14-day regimen) is required to cure patients of Plasmodium vivax malaria. If a patient is not cured of P. vivax, they are at risk of relapse with increasing risk of morbidity and further transmission of the parasite.5,6 Relapse contributes to more than 50% of the disease burden in a community.7,8 A single dose of tafenoquine, another 8-aminoquinoline, when given with chloroquine is capable of curing a patient of P. vivax.9 Tafenoquine, recently approved by the United States Food and Drug Administration (FDA) for radical cure of P. vivax, under the Krintafel label, is indicated for individuals with greater than 70% G6PD activity. Tafenoquine has also been approved by the FDA with a different dosage for prophylaxis, under the Arakoda label, with similar indications for G6PD Deficiency. Many countries will struggle to meet their target malaria elimination goals without broader safe access to radical cure of P. vivax. Diagnostic tests that determine a patient’s G6PD status are needed at or near where they seek treatment.10 Glucose-6-Phosphate Dehydrogenase Deficiency is determined by measuring G6PD activity, adjusted for temperature, in blood normalized for either red blood cell count or hemoglobin. Quantitative testing for G6PD is performed in reference or specialized laboratories using a complex assay on a temperature-regulated instrument because of the large temperature impact on enzyme activity. The most commonly used test for clinical screening is the qualitative fluorescent spot test, which accurately discriminates hemizygous-deficient males and homozygous- or heterozygous-deficient females, who typically have G6PD activity less than 30% of normal. Although this is adequate for males who are either deficient ( 80% activity), it is inadequate to classify females who can be G6PD deficient, intermediate (30–80% activity), or normal.11–15 Quantitative point-of-care G6PD tests that can be used in low-resource settings can impact health on many levels, including reductions in neonatal morbidity and mortality. It can also impact health by providing access to safe, radical, curative treatment for P. vivax malaria, which can then prevent relapse burden, onward malaria transmission, and accelerate malaria elimination.7–10,16 Both qualitative and quantitative G6PD Deficiency tests that can be performed closer to the patients are beginning to emerge.17–19 In 2017, the production of a commonly used reference assay for evaluating new G6PD products, the G6PDH quantitative test by Trinity Biotech, was suspended.20 This study presents the results of a bridging evaluation of the Trinity Biotech kit against a commercially available U.S. Food and Drug Administration–cleared reference assay by Pointe Scientific. The innovative, point-of-care STANDARD G6PD test by SD Biosensor was also evaluated against the same reference assay.