A new automated method for the determination of the Total Antioxidant Capacity (TAC) of human plasma, based on the crocin bleaching assay

BACKGROUND: Antioxidant molecules, which scavenge free radical species to prevent or delay oxidative damage of important macromolecules, membrane lipids and lipoproteins, are prevalent in plasma and other biological fluids. Among them, bilirubin, uric acid and protein thiols are the major endogenous antioxidants, while vitamins C and E, as well as a number of food-derived (poly)aromatic substances, belonging to stilbens, flavonoids and phenolic acids, are the main classes of nutritional antioxidants. Assays for total antioxidant capacity in plasma differ in their type of oxidation source, target and measurement used to detect the oxidized product. METHODS: In the present work we present an automated assay for the estimation of blood total antioxidant capacity (TAC assay), based on the crocin bleaching (oxidation) method. This method was adapted on a modern autoanalyzer, was linear over a wide range of values (0–3 mmol/L), and performed using an end point measurement. RESULTS: The TAC method presented a linear correlation with another automated commercial Total Antioxidant Status (TAS) test. Detection of the interference of different metabolites revealed a significant participation of TAC from uric acid, bilirubin, albumin, a minor interference from ascorbic acid, and no interference from hemoglobin. TAC was not modified by two freeze/thawing cycles, and was stable in samples stored at room temperature for 4 hours. K-EDTA and heparin were the best anticoagulants, while citrate decreased TAC by 20%. Reference values derived from samples of normal blood donors was 1.175 ± 0.007 mmol/L (mean ± SEM), while a diet rich in antioxidants more than doubled this value. CONCLUSIONS: The proposed TAC assay, is fully automated, stable and reliable, and could be of value in the estimation of the AC of plasma. It is further proposed to calculate the antioxidant capacity of plasma after a subtraction of all interference deriving from endogenous and/or exogenous metabolites. The antioxidant capacity of plasma thus calculated can be used as a useful indicator of the antioxidant value of foods and beverages in the daily diet

Relationships of low serum vitamin D3 with anthropometry and markers of the metabolic syndrome and diabetes in overweight and obesity

Low serum 25 hydroxyvitamin D3 (vitamin D3) is known to perturb cellular function in many tissues, including the endocrine pancreas, which are involved in obesity and type II diabetes mellitus (TIIDM). Vitamin D3 insufficiency has been linked to obesity, whether obesity is assessed by body mass index (BMI) or waist circumference (waist). Central obesity, using waist as the surrogate, is associated with the metabolic syndrome (MetSyn), insulin resistance, TIIDM and atherosclerotic cardiovascular disease (CVD). We tested how vitamin D3 was related to measures of fat mass, MetSyn markers, haemoglobin A1c (HbA1c) and MetSyn in a cross-sectional sample of 250 overweight and obese adults of different ethnicities. There were modest inverse associations of vitamin D3 with body weight (weight) (r = -0.21, p = 0.0009), BMI (r = -0.18, p = 0.005), waist (r = -0.14, p = 0.03), [but not body fat % (r = -0.08, p = 0.24)], and HbA1c (r = -0.16, p = 0.01). Multivariable regression carried out separately for BMI and waist showed a decrease of 0.74 nmol/L (p = 0.002) in vitamin D3 per 1 kg/m2 increase in BMI and a decrease of 0.29 nmol/L (p = 0.01) per 1 cm increase in waist, with each explaining approximately 3% of the variation in vitamin D3 over and above gender, age, ethnicity and season

The prevalence of nutritional anemia in pregnancy in an east Anatolian province, Turkey

<p>Abstract</p> <p>Background</p> <p>Anemia is considered a severe public health problem by World Health Organization when anemia prevalence is equal to or greater than 40% in the population. The purpose of this study was to determine the anemia prevalence with the associated factors in pregnant women and to determine the serum iron, folate and B12 vitamin status in anaemic pregnants in Malatya province.</p> <p>Methods</p> <p>This is a cross-sectional survey. A multi-sage stratified probability-proportional-to-size cluster sampling methodology was used. A total of 823 pregnant women from sixty clusters were studied. Women were administered a questionnaire related with the subject and blood samples were drawn. Total blood count was performed within four hours and serum iron, folate and B12 vitamin were studied after storing sera at -20 C for six months.</p> <p>Results</p> <p>Anemia prevalence was 27.1% (Hb < 11.0 gr/dl). Having four or more living children (OR = 2.2), being at the third trimester (OR = 2.3) and having a low family income (OR = 1.6) were determined as the independent predictors of anemia in pregnancy. Anemia was also associated with soil eating (PICA) in the univariate analysis (p < 0.05). Of anaemic women, 50.0% had a transferrin saturation less than 10% indicating iron deficiency, 34.5% were deficient in B12 vitamin and 71.7% were deficient in folate. Most of the anemias were normocytic-normochromic (56.5%) indicating mixed anemia.</p> <p>Conclusions</p> <p>In Malatya, for pregnant women anemia was a moderate public health problem. Coexisting of iron, folate and B vitamin deficiencies was observed among anaemics. To continue anemia control strategies with reasonable care and diligence was recommended.</p

Treatment of Gaucher disease with an enzyme inhibitor

The hypothesis is offered predicting that Caucher patients could be treated with a drug that slows the synthesis of glucosylceramide, the lipid that accumulates in this disorder. The present therapeutic approach involves augmenting the defective enzyme, glucosylceramide β-glucosidase, with exogenous β-glucosidase isolated from human tissue. This spectacularly expensive mode of treatment should be replaceable with a suitable enzyme inhibitor that simply slows formation of the lipid and matches the rate of synthesis with the rate of the defective, slowly working β-glucosidase. Several drugs that possess this ability are available, the best known of which is 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), a designer inhibitor that resembles the synthase's substrate and product. PDMP has been found to be effective in mice, rats, fish, and a wide variety of cultured cells. Its use, at suitable dosages, seems to be harmless, although long-term tests have not been made. The lack of suitable animal models of Gaucher disease has made it difficult to test the hypothesis adequately, but PDMP does rapidly lower the levels of glucosylceramide in normal animal tissues and the animals evidently do well with the lowered levels of glucosylceramide and its more complex glycolipid metabolites.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45689/1/10719_2004_Article_BF00731489.pd

Total antioxidant activity and trace elements in human milk: the first 4 months of breast-feeding

The content of many nutrients in breast milk are dependent on the nutritional status of the lactating woman. This is particularly true for fat and water-soluble vitamins, some of which have antioxidant properties. The aim of the study entertained herein was to evaluate the changes in total antioxidant status of human milk during the first 4 months of lactation, and to correlate such changes with the contents in specific antioxidant oligoelements (Cu, Zn, Mn and Se). Milk samples were collected from (31) lactating women recruited at the Service of Obstetrics of the Hospital de São João in Porto, after 1, 4, 8, 12 and 16 weeks after birth. The total antioxidant status (TAS) of human milk was measured by the Randox® commercial kit and trace metals by ICP-MS (inductively coupled plasma-mass spectrometry). The results found for TAS and oligoelements under study show a decrease in the concentration of these parameters from 7 days to 4 months of breast-feeding and significant correlations (p < 0.05) were found between TAS and Cu, Zn and Se (not Mn). The decreases of Cu, Zn and Se were also correlated, but not proportional between them, suggesting diverse excretion mechanisms for all. Between primipara and multipara women, a significant difference was found only for Cu and Zn concentrations at 7 days of lactation, but not for the other metals or TAS. With respect to the mother’s age, no correlation was found, either for trace metal concentrations or TAS

Reduced Quantitative Ultrasound Bone Mineral Density in HIV-Infected Patients on Antiretroviral Therapy in Senegal

Background: Bone status in HIV-infected patients on antiretroviral treatment (ART) is poorly documented in resource-limited settings. We compared bone mineral density between HIV-infected patients and control subjects from Dakar, Senegal. Methods: A total of 207 (134 women and 73 men) HIV-infected patients from an observational cohort in Dakar (ANRS 1215) and 207 age-and sex-matched controls from the general population were enrolled. Bone mineral density was assessed by quantitative ultrasound (QUS) at the calcaneus, an alternative to the reference method (i.e. dual X-absorptiometry), often not available in resource-limited countries. Results: Mean age was 47.0 (+/- 8.5) years. Patients had received ART for a median duration of 8.8 years; 45% received a protease inhibitor and 27% tenofovir; 84% had undetectable viral load. Patients had lower body mass index (BMI) than controls (23 versus 26 kg/m(2), P<0.001). In unadjusted analysis, QUS bone mineral density was lower in HIV-infected patients than in controls (difference: -0.36 standard deviation, 95% confidence interval (CI): -0.59;-0.12, P = 0.003). Adjusting for BMI, physical activity, smoking and calcium intake attenuated the difference (-0.27, CI: -0.53; -0.002, P = 0.05). Differences in BMI between patients and controls explained a third of the difference in QUS bone mineral density. Among patients, BMI was independently associated with QUS bone mineral density (P<0.001). An association between undetectable viral load and QUS bone density was also suggested (beta = 0.48, CI: 0.02; 0.93; P = 0.04). No association between protease inhibitor or tenofovir use and QUS bone mineral density was found. Conclusion: Senegalese HIV-infected patients had reduced QUS bone mineral density in comparison with control subjects, in part related to their lower BMI. Further investigation is needed to clarify the clinical significance of these observations

Vitamin D Deficiency and Its Health Consequences in Africa

Africa is heterogeneous in latitude, geography, climate, food availability, religious and cultural practices, and skin pigmentation. It is expected, therefore, that prevalence of vitamin D deficiency varies widely, in line with influences on skin exposure to UVB sunshine. Furthermore, low calcium intakes and heavy burden of infectious disease common in many countries may increase vitamin D utilization and turnover. Studies of plasma 25OHD concentration indicate a spectrum from clinical deficiency to values at the high end of the physiological range; however, data are limited. Representative studies of status in different countries, using comparable analytical techniques, and of relationships between vitamin D status and risk of infectious and chronic diseases relevant to the African context are needed. Public health measures to secure vitamin D adequacy cannot encompass the whole continent and need to be developed locally

Evaluation of the OptiMAL Test for Rapid Diagnosis of Malaria

This study evaluated the ability of a newly developed rapid test for laboratory diagnosis of malaria. OptiMAL is a rapid test that utilizes a dipstick coated with monoclonal antibodies against the intracellular parasite dehydrogenase (PLDH). The differentiation of Plasmodium species is based on antigenic differences between the PLDH forms. Blood samples from 62 of clinically diagnosed patients were examined using the microscopy of Giemsa-stained blood films and the OptiMAL test. The blood films indicated that 27% of the patients were positive for P.falciparum (including one case of mixed infection with P. malariae), while the OptiMAL test recorded 34% for P. falciparum. The OptiMAL test failed to diagnose malaria at concentrations less than 100 per microliter of blood, while those missed by microscopy may be due to sequestration of the parasite coupled with low parasite density. The OptiMAL test was modified by using fingerprick instead of venepuncture and this simplifies the test both in terms of cost and trained personnel. There was no significant difference between the two methods (x2 = 1.513;P>0.05), but the OptiMAL test has the advantages of being faster, requires almost no specialized laboratory experience and extremely sensitive and specific even in field situations. We conclude that the OptiMAL test is an effective tool for the rapid diagnosis of malaria. (Af. J. of Clinical and Experimental Microbiology: 2003 4(1): 14-17