Platelet enzyme abnormalities in leukemias.

Aim of the Study: The aim of this study was to evaluate platelet enzyme activity in cases of leukemia. Materials and Methods: Platelet enzymes glucose-6-phosphate dehydrogenase (G6PD), pyruvate kinase (PK) and hexokinase (HK) were studied in 47 patients of acute and chronic leukemia patients, 16 patients with acute myeloid leukemia (AML)(13 relapse, three in remission), 12 patients with acute lymphocytic leukemia (ALL) (five in relapse, seven in remission), 19 patients with chronic myeloid leukemia (CML). Results: The platelet G6PD activity was significantly low in cases of AML, ALL and also in CML. G6PD activity was normalized during AML remission. G6PD activity, although persistently low during ALL remission, increased significantly to near-normal during remission (P < 0.05) as compared with relapse (P < 0.01). Platelet PK activity was high during AML relapse (P < 0.05), which was normalized during remission. Platelet HK however was found to be decreased during all remission (P < 0.05). There was a significant positive correlation between G6PD and PK in cases of AML (P < 0.001) but not in ALL and CML. G6PD activity did not correlate with HK activity in any of the leukemic groups. A significant positive correlation was however seen between PK and HK activity in cases of ALL remission (P < 0.01) and CML (P < 0.05). Conclusions: Both red cell and platelet enzymes were studied in 36 leukemic patients and there was no statistically significant correlation between red cell and platelet enzymes. Platelet enzyme defect in leukemias suggests the inherent abnormality in megakaryopoiesis and would explain the functional platelet defects in leukemias.

Changes in incidence and sex ratio of glucose-6-phosphate dehydrogenase deficiency by population drift in Taiwan.

We analyzed data from a single screening center in Taiwan from January 1, 1996 to December 31, 2005 to evaluate the change in incidence and female to male ratio of G6PD deficiency. During the study period, 1,211,632 of 2,667,922 (45.41%) neonates delivered in Taiwan were screened at the National Taiwan University Hospital. Of these, 21,997 neonates (1.82%) were confirmed to have G6PD deficiency. The annual incidence has decreased since 2002, from 1.94% to 1.61%. During this period, the male to female ratio in the screened population was 1.091 (range 1.073-1.098), the incidences in male and female neonates were 2.81% (2.57-3.07%), and 0.7% (0.45-0.95%), respectively. The change in sex ratio of the disease was unrelated to the change in incidence. During 2000-2005, 15-25% of newborns were born from newly immigrated females. G6PD deficiency screening has confirmed a subtle genetic flow in Taiwan. Besides the psychosocial effects, medical issues caused by population movements should be carefully watched in the future in Taiwan.

Level of oxidative stress in the red blood cells of patients with liver cirrhosis.

BACKGROUND & OBJECTIVE: Liver cirrhosis is associated with gastrointestinal haemorrhage and oesophageal variceal bleeding. Altered platelet functions has been reported to be a cause of bleeding complication. We carried out this study to find out the level of oxidative stress in the red blood cells of patients with liver cirrhosis. METHODS: Fifty patients admitted with the complication of liver cirrhosis (with bleeding complications, n=30 and without bleeding complications, n=20) were included in the study. Age and sex matched normal healthy volunteers (n=45) served as controls. The levels of oxyhaemoglobin and methaemoglobin were assayed in the red blood cells. Oxidative stress markers such as lipid peroxides, lipid hydroperoxides and nitric oxide were determined along with enzymatic antioxidants. Membrane bound adenosine triphosphatases, cytosolic glucose-6-phosphate dehydrogenase and NADHmethaemoglobin reductase were also measured. The levels of cholesterol and total phospholipids were assessed in red blood cell membrane. The osmotic fragility of red blood cells was monitored using different concentrations of sodium chloride. RESULTS: The level of methaemoglobin was significantly higher (P < 0.001) in the red blood cells of liver cirrhotic patients with bleeding complication compared to that of non bleeding patients. The activity level of NADH-methaemoglobin reductase was significantly lower (P<0.001) compared to that of normal subjects. Levels of oxidative stress markers including nitric oxide were found to be higher in patients. The levels of enzymatic antioxidants were low except of glutathione peroxidase. The activity levels of adenosine triphosphatases were also found to be significantly lower (P<0.001) in patients compared to normal subjects. A significant alteration (P<0.05) was found in membrane cholesterol/phospholipid ratio of cirrhotic bleeders. Osmotic fragility of red blood cells was also altered in patients. INTERPRETATION & CONCLUSION: In cirrhotic condition red blood cells are subjected to severe oxidative stress with significant alterations in the membrane properties.

Effects of paraquat on anti-oxidant system in rats.

The toxic effects of paraquat on the anti-oxidant defense system of male albino rats were evaluated, after administering either a single dose (1.5 and 7.5 mg/kg of body weight) or continuous daily doses (same as above, i.e., 1.5 mg/kg and 7.5 mg/kg of body weight) for 3 and 7 days. Glutathione levels in blood cells, liver, lung and kidney tissues decreased in a dose and time dependent manner. Glutathione reductase and glucose-6-phosphate dehydrogenase activity decreased, whereas the activity of glutathione-S-transferase, glutathione peroxidase, catalase and superoxide dismutase increased in paraquat exposure. Malondialdehyde formation also increased in a dose and time dependent manner. The alterations of anti-oxidant system particularly glutathione can be utilized as biomarkers during management of paraquat poisoning.

Histochemical localization of enzymes and lipids in the ovary of a vespertilionid bat, Scotophilus heathi, during the reproductive cycle

O presente estudo descreve as mudanças sazonais na D5 3b hidroxiesteróide desidrogenase (3b-HSD), glicose-6 fosfato desidrogenase (G-6-PD), e lipídios no ovário de um morcego vespertilionidae, Scotophilus heathi. As atividades totais dos lipídios e do 3b-HSD estão restritas às células tecais e intersticiais do ovário. Os lipídios, 3b-HSD e G-6-PD totais, aumentaram significantemente durante a recrudescência, e permaneceram elevados durante a dormência de inverno e o período de acasalamento, quando comparados a outras fases reprodutivas. A alta incidência de atividade de lipídios e enzimas nas células intersticiais durante o período de acasalamento e durante o período de ovulação sugere claramente que estas células estão ativamente envolvidas na esteroidogênese. O declínio da atividade dos lipídios e enzimas durante a dormência de inverno, o qual se correlaciona com os níveis decrescentes da esteroidogênese, podem ser o fator responsável pela longa sobrevivência do folículo de De Graaf no ovário do S. heathi.

New Helicoverpa armigera Hbn cell line from larval hemocyte for baculovirus studies.

A new cell line from the larval hemocytes of H. armigera was established in Grace's medium modified by adding lactalbumin hydrolysate and yeastolate (3.3g/l), and supplemented with fetal bovine serum (20%). The cell line was designated as NIV-HA-1195. The cell population at P-78 consisted mainly of epithelial-like cells (89.36%), fibroblast-like cells (8.31%) and giant cells (2.13%). The population doubling time was 96hr at P-8, 60hr at P-43. The chromosome number ranged from 45 to 200. The cell line is susceptible to the baculoviruses, Autographa californica nucleopolyhedrovirus (AcNPV), Spodoptera litura NPV and the homologous HaNPV. Isoenzyme profile and results of 16S rRNA heteroduplex analysis clearly indicated the species specificity of the new cell line.

Neonatal jaundice in very low birth weight babies.

Very low birth weight (VLBW) neonates born between January 1995 to December 1998, who survived for > 2 days, were studied for the incidence, causes and interventions required for neonatal jaundice. Significant neonatal jaundice was defined as the total serum bilirubin (TSB) level beyond which baby required intervention (phototherapy and/or exchange transfusion) for neonatal jaundice. The incidence of significant neonatal jaundice (NNJ) was 76.6% and 37.3% required exchange transfusion. It was 82.9% at gestational age < or = 28 weeks reduced whereas to 56.9% at gestational age of 35-36 weeks. The incidence was 75.3%, 78.5% and 76.7% in the birth weight group of 750-799 grams, 1000-1249 grams and 1250-1499 grams respectively. Glucose 6 phosphatase dehydrogenase (G-6-PD) deficiency (12.1%) was the commonest cause of jaundice. There is a need for evaluation of prophylactic therapies that enhances liver function or decreases production of bilirubin, which would prevent the rise of TSB to dangerous levels and thus would decrease the need for exchange transfusions.

Dos nuevas mutaciones de glucosa 6 fosfato deshidrogenasa, G6PD Santiago y G6PD Calvo Mackenna / Two new glucose 6 phosphate dehydrogenase mutations, G6PD Santiago and G6PD Calvo Mackenna

Se describen dos nuevas mutaciones que producen deficiencia de G6PD, ambas en niños chilenos con anemia hemolíticas crónica no esferocítica (AHCNE). La mutación G6PD Santiago es debida a un cambio de arginina a prolina en el aminoácido 198, lo que lleva a una sustitución de guanina por citosina en el nucleótido 593 del exon 6. En la mutación G6PD Calvo Mackenna hay un cambio de valina a isoleucina en el aminoácido 380, lo que produce una sustitución de adenina por guanina en el nucleotido 1138 del exon 10 de la enzima. Los estudios para el diagnóstico de ellas se realizaron en "The Scripps and Research Institute de La Jolla, California, USA" por gentileza del Dr Ernest Beutler

Lesiones intraepiteliales de cuello uterino: marcadores bioquímicos y virus de papiloma humano / Intraepithelial lesions of the uterine cervix: biochemical markers and human papillomavirus

Con el fin de establecer el valor de ciertos marcadores indicadores del grado de evolución de las neoplasias intraepiteliales cervicales (CIN), se realizó la determinación de glucosa-6-fosfato deshidrogenasa (G6PDH) por enzimoquímica y de antígeno carcinoembrionario (CEA) por inmunomarcación en biopsias y extendidos citológicos, procedentes de cervix uterinos en casos de infección por virus de papiloma humano (HPV) y de CIN de diferentes grados (CIN 1 a CIN 3). La actividad de G6PDH, ensayada en células exfoliadas, fue en aumento desde CIN 1 a CIN 3, donde alcanzó el nivel 3+ en una escala fijada con un máximo de 4+ para el carcinoma pavimentoso. El CEA, demostrado en cortes histológicos y en células exfoliadas de diversas patología de cérvix uterino, varió desde 1+ en las lesiones de bajo grado hasta 3+ en las de alto grado. De los datos obtenidos en G6PDH y CEA, podría inferirse que las lesiones intraepiteliales de cérvix uterino se suceden en forma continua desde la lesión viral hasta CIN 3. Se realizó la tipificación de HPV mediante hibridación in situ. En los condilomas y CIN 1 fue detectado HPV 6/11 episomal y en los CIN 2 se encontraron tipos virales de moderado y alto riesgo predominantemente libres. Todos los CIN 3 fueron positivos para HPV 16/18 en estado integrado. Sin embargo, la presencia de HPV 16/18 no sería un factor por sí mismo suficiente para la completa transformación celular, aunque su presencia sea necesaria para la promoción de la neoplasia cervical

Differences in enzyme activity and biological behavior of three leishmania promastigotes isolated from patients with zoonotic cutaneous leishmaniasis

Zoonotic cutaneous leishmaniasis [ZCL] is reported to cause a spectrum of clinical manifestations. To unravel some of the mechanisms associated with different disease manifestations, enzyme activities were compared among the promastigotes of leishmania isolated from three clinically different forms of ZCL from Isfahan, central Iran. Specific activities of glucose-6-phosphate dehydrogenase, hexokinase, lactate dehydrogenase and acid phosphatase in the promastigotes isolated from a scaly flat ulcer were 5.5, 2.2, 1.6 and 2.6 folds greater respective to those isolated from a small papular lesion. The activity of these enzymes in the promastigotes isolated from a volcano-shaped lesion was notably higher than those isolated from a papular lesion, but lower than those isolated from a scaly flat ulcer. Significant differences were not observed in alkaline phosphatase activity of different isolates. These results may indicate that differences in the clinical manifestation of the lesions in ZCL might be related to certain metabolic pathways of the parasites, growth kinetics in NNN medium and the course of infection in BALB/C mice

frequency of Hb S and glucose-6-phosphate dehydrogenase phenotypes in relation to malaria in western Saudi Arabia

This study was conducted on 6265 Saudi males and females living in six different areas i.e. Yanbu, Makkah, AI-Qunfuda, Bisha, AI-Baha and Jaizan, in western Saudi Arabia. It was conceived to determine and relate the frequency of Hb S and of glucose-6-phosphate dehydrogenase [G-6-PD] deficiency phenotypes in the different areas and to relate them to malaria endemicity. The sickle cell gene was encountered in each of the areas investigated at frequencies ranging from 0.015 in Yanbu to 0.115 in AI-Qunfuda. The normal G-6-PD in each region was G-6-PD-B+, and variants identified included G-6-PD-A+, G-6-PD-A-, G-6-PD-Mediterranean and G-6-PD-Weak. Severe G-6-PD deficiency was encountered in each region and was caused mainly by G-6-PD-Mediterranean at frequencies ranging from 0.0179 to 0.204 in the male population and 0.0064 to 0.1158 in the female population. This paper shows significant differences in the frequencies of G-6-PD phenotypes and Hb S genes within malaria endemic regions

Estandarización de las técnicas para la caracterización de la glucosa 6 fosfato deshidrogenasa eritrocitaria / Standardization techinique for erythrocyte glucose 6 phosphate dehydrogenase characterization

Se comparan dos técnicas bioquímicas para la determinación de los niveles de glutation reducido y su estabilidad. Se establecen los valores normales de las determinaciones utilizadas durante la caracterización de la variente enzímatica en las condiciones de nuestro laboratorio, para lo que se emplea un grupo control. Se concluye que la utilización de un blanco de acetilfenilhidracina permite emplear sin dificultad la técnica del ditiobis para la cuantificación de glutation reducido, la cual resulta más sensible que la del nitroprusiato. Los resultados obtenidos en el grupo control no revelan diferencias significativas con respecto a los encontrados por otros autores

Lactate dehydrogenase and phosphoglucose isomerase in patients with retinoblastoma and congenital cataract

Os autores determinaram a atividade enzimática da desidrogenase láctica (LDH) e da fosfoglicose isomerase (PGI) no humor aquoso (HA) e soro (S) de pacientes com catarata congênita. Encontraram uma diferença estatiscamente significativa entre as médias da desidrogenase láctica no humor aquoso (LDHha), da fosfoglicose isomerase no humor aquoso (PGIha) e da desidrogenase láctica no soro (LDHs) nos dois grupos de pacientes. Dos portadores de retinoblastoma, 75.0%, 70.0%, 10.8% e 8.1% apresentaram aumento de LDHha, PGIha, LDHs e PGIs, respectivamente, quando comparados com os portadores de catarata congênita. No grupo de portadores de catarata congênita, näo houve correlaçäo ente as enzimas no humor aquoso e/ou soro. No grupo de portadores de retinoblastoma, houve uma correlaçäo positiva entre as duas enzimas no humor aquoso e entre as duas enzimas no soro. O padräo isoenzimático da LDH no humor aquoso dos portadores de retinoblatoma apresentou, como fraçöes mais elevadas, as isoenzimas LDH4 e LDH3. Do ponto de vista enzimático, o valor absoluto da LDH e da PGI no humor aquoso constitui o melhor critério para o diagnóstico de retinoblastoma. Resultados falso-negativos foram observados em 25% das dosagens da LDHha e em 30% das dosagens da PGIha

Isoenzyme analyses of Malaysian Schistosoma, S. mekongi and S. japonicum by isoelectric focusing in polyacrylamide gel.

Isoenzyme patterns of adult Malaysian Schistosoma, S. mekongi and S. japonicum strains were analysed by isoelectric focusing (IEF) in polyacrylamide gel. Enzyme patterns obtained from Malaysian Schistosoma homogenates differed from those of S. mekongi and S. japonicum strains. Malaysian Schistosoma was found to differ from S. japonicum by 8 enzymes, namely phosphoglucomutase, phosphoglucoisomerase, malate dehydrogenase, acid phosphatase, hydroxy-butyrate dehydrogenase, hexokinase and alkaline phosphatase, and from S. mekongi by phosphoglucomutase, malate dehydrogenase, aldolase and alkaline phosphatase. These results and the distinct biology of the parasite suggest that Malaysian Schistosoma is a new species in the S. japonicum complex.

Metabolic studies on mycobacteria-I. Demonstration of key enzymes of glycolysis and tricarboxylic acid cycle on polyacrylamide gels.

Polyacrylamide gel electrophoresis (PAGE) technique was standardised to demonstrate some key enzymes of glycolysis, hexose mono phosphate (HMP) pathway and tricarboxylic acid cycle in slow growing mycobacteria (M. avium. M. gastri) as well as in fast growing mycobacteria (M. vaccae, M. phlei). The enzymes studied were lactate dehydrogenase (LDH) glucose-6-phosphate dehydrogenase (G6PD), aconitase, isocitrate dehydrogenase (ICD), succinic dehydrogenase (SDH), fumerase and malate dehydrogenase (MDH). All the three pathways were found to be operative in slow as well as fast growing mycobacteria. Using this technique M. leprae specific MDH activity was demonstrated in the cell free extract of M. leprae. It's (MDH) electrophoretic mobility on gels lies in the range shown by other mycobacterial species studied and was distinct from that of host MDH. It appears that PAGE offers a useful tool for metabolic characterization of M. leprae using infected tissues.