Renata da Silva Pereira

A simple and inexpensive automated technique for measurement of serum nitrite/nitrate

OBJECTIVE We described an automated technique for measurement of serum nitrite/nitrate (NO(x)) using the Cobas Mira clinical chemistry analyzer. DESIGN AND METHODS NO(x) was measured by the modified Griess method. Precision, accuracy, linearity, instrument carry-over and lower limit of quantitation (LLOQ) were assessed. RESULTS The automated technique for measurement of serum NO(x) was linear, precise, and accurate. It has a LLOQ of 2.0 μmol/L. CONCLUSION Serum NO(x) measured by the modified Griess method can be applied easily to the Cobas Mira clinical chemistry analyzer.

Assessment of Oxidative, Inflammatory, and Fibrinolytic Biomarkers and DNA Strand Breakage in Hypercholesterolemia

The aim of this study was to assess the levels of oxidative, inflammatory, and fibrinolytic biomarkers as well as DNA strand breakage in hypercholesterolemic subjects. Fasting glucose, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, uric acid, total protein, albumin, apolipoprotein (Apo) A, Apo B, advanced oxidation protein products (AOPP), increased ischemia-modified albumin (IMA), ―SH, NOx, IL-6, and D-dimer levels were assessed, and DNA strand breakage was evaluated using comet assay in 38 patients with hypercholesterolemia and 20 healthy controls. Total cholesterol, triglycerides, LDL cholesterol, Apo A, Apo B, AOPP, IMA, IL-6, and D-dimer concentrations were significantly higher in subjects with hypercholesterolemia. However, NOx and plasma ―SH group concentrations were lower in hypercholesterolemic subjects, while no significant differences were observed with respect to DNA strand breakage between the two groups. Hypercholesterolemia is related to oxidative stress and inflammation. Accordingly, AOPP concentration was higher in subjects with hypercholesterolemia, and we speculate that AOPP can reflect the enhancement of protein oxidation and inflammation.

Assessment of the nickel-albumin binding assay for diagnosis of acute coronary syndrome

Abstract Background: Myocardial ischemia may alter the metal binding capacity of circulating serum albumin. Thus, the aim of this study was to describe an automated method to measure ischemia-induced alterations in the binding capacity of serum albumin for exogenous nickel, and to evaluate the diagnostic characteristics of this assay for the assessment of acute coronary syndrome (ACS) in patients presenting to the emergency room (ER) with acute chest pain. Methods: We assessed the concentrations of cardiac troponin I (cTnI), serum albumin, ischemia-modified albumin (IMA) measured by the cobalt-albumin binding assay (CABA), and by an automated nickel-albumin binding assay (NABA) in the following groups: ACS (n=63) and non-ischemic chest pain (NICP, n=26). Biochemical markers were determined in blood samples obtained from patients within 3 h of ER admission. Results: cTnI, CABA and NABA concentrations were higher in ACS group in comparison to the NICP group. A significant correlation between NABA and CABA was observed (r=0.5387, p<0.001). Areas under the curve for CABA and NABA were 0.7289 and 0.7582, respectively. Both CABA and NABA have the ability to discriminate patients with ACS. However, NABA has a slightly higher ability to discriminate ACS compared with CABA. Conclusions: Patients with ACS have reduced nickel binding to human serum albumin, and NABA may have an important role as an early marker of myocardial ischemia, particularly in patients presenting to the ER with acute chest pain.

A simple, fast and inexpensive automated technique for measurement of plasma nitrite

Renata da Silva Pereira, Sı́lvia Juliane Piva, Etiane Tatsch, Helena Kober, Patrı́cia Gomes, Jarbas Rodrigues de Oliveira and Rafael Noal Moresco* 1 Laboratório de Bioquı́mica Clı́nica, Departamento de Análises Clı́nicas e Toxicológicas, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil 2 Programa de Pós-Graduação em Ciências Farmacêuticas, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil 3 Curso de Farmácia, Centro Universitário Franciscano, Santa Maria, RS, Brazil 4 Laboratório de Biofı́sica Celular e Inflamação, Pontifı́cia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil

Influência dos anticoagulantes e da temperatura de armazenamento sobre os níveis sanguíneos de nitrito

The measurement of nitric oxide metabolites may be useful for better understanding of different physiopathological processes. Thus, the aim of this study was to evaluate the influence of different anticoagulants (EDTA, citrate and heparin) and four-month storage at -20oC on nitrite levels. The serum and plasma samples were analyzed by using the Griess method. The type of sample (serum or plasma) or anticoagulant used in the collection did not influence on nitrite levels significantly, regardless the fact they were fresh or four-month samples stored at -20oC.

A prospective study on Aeromonas in outpatients with diarrhea in the central region of Rio Grande do Sul State

Aeromonas spp. were identified in five (2,7%) of 182 diarrheal stool cultures, A. caviae was predominant, resistant mainly to ampicillin and cephalotin. This is the first study showing the presence of Aeromonas spp. in diarrheal stools of outpatients in the central region of Rio Grande do Sul State, Brazil.

Free and nanoencapsulated vitamin D3: effects on E‐NTPDase and E‐ADA activities in an animal model with induced arthritis

The effect of vitamin D3 in oral solution (VD3) and vitamin D3‐loaded nanocapsules (NC‐VD3) was analysed in animals with complete Freunds adjuvant (CFA) induced arthritis (AR). For this purpose, we evaluated scores for arthritis, thermal hyperalgesia and paw oedema, as well as histological analyses and measurements of the activity of the ectonucleoside triphosphate diphosphohydrolase (E‐NTPDase) and ecto‐adenosine deaminase (E‐ADA) enzymes in rat lymphocytes. Haematological and biochemical parameters were also determined. The doses administered were 120 UI/day of VD3 and 15.84 UI/day of NC‐VD3. Fifteen days after the induction of AR, the groups were treated for 15 days with vitamin D3. The results demonstrated that VD3 was able to reduce arthritis scores, thermal hyperalgesia and paw oedema in rats with CFA‐induced arthritis. However, treatment with NC‐VD3 did not reduce arthritis scores. The histological analyses showed that both formulations were able to reduce the inflammatory changes induced by CFA. The activity of E‐NTPDase in rat lymphocytes was higher in the AR compared with the control group, while the activity of E‐ADA was lower. This effect was reversed after the 15‐day treatment. Data from this study indicates that both forms of vitamin D3 seem to contribute to decreasing the inflammatory process induced by CFA, possibly altering the activities of ectoenzymes. Copyright