Validação do dispositivo automático de medição da pressão arterial, OMRON® M6 Comfort, segundo o Protocolo Internacional da Sociedade Europeia de Hipertensão (2010)

Introdução – A medição da pressão arterial (PA), utilizando dispositivos automáticos, é frequentemente realizada na prática clínica e na automedição, permitindo adquirir informação fiável para o diagnóstico, controlo e tratamento da hipertensão arterial. Porém, muitos dos dispositivos automáticos disponíveis no mercado não estão validados segundo protocolos existentes para o efeito. O objetivo do estudo foi confirmar a validação do dispositivo de medição automática da PA, OMRON® M6 Comfort, segundo o Protocolo Internacional da European Society of Hypertension (ESH), de 2010, para a validação de dispositivos de medição automática da PA em adultos. Metodologia – Foram estudados 33 indivíduos, aos quais foram realizadas 9 medições sequenciais da PA, no braço esquerdo, com um esfignomanómetro aneróide alternando com o dispositivo automático. Seguidamente avaliaram-se as diferenças entre os valores obtidos pelos dispositivos para a pressão arterial sistólica (PAS) e diastólica (PAD), classificando-as em três níveis (≤ 5, ≤ 10 ou ≤ 15 mmHg). O número das diferenças em cada nível foi comparado ao requerido pelo Protocolo (fase 1.1). Para cada sujeito foi ainda determinado o número de diferenças com valores ≤ 5 mmHg. Pelo menos 24 dos 33 indivíduos devem ter 2 ou 3 diferenças com valores ≤ 5 mmHg e no máximo 3 dos 33 indivíduos podem apresentar as 3 diferenças com valores > 5 mmHg (fase 1.2). Resultados – O dispositivo OMRON® M6 Comfort foi aprovado nas fases 1.1 e 1.2 para a PAS e PAD. A média das diferenças entre as medições da PA, determinada pelos dispositivos automático e manual, foi de -0,82 ± 5,62 mmHg para a PAS e 2,14 ± 5,15 mmHg para a PAD. Considerações Finais – O dispositivo OMRON® M6 Comfort é válido para a medição da PA em adultos, de acordo com o Protocolo Internacional da ESH, de 2010. - ABSTRACT - Introduction – The measurement of blood pressure (BP) using automatic devices is often performed in clinical practice and self-measurement allowing the acquisition of reliable information for the diagnosis, monitoring and treatment of hypertension. However not all of the automated devices available in the market are validated in accordance with the existing protocols for this purpose. The purpose of this study was to confirm the validation of the automatic measuring device of the BP, OMRON® M6 Comfort, according to the “European Society of Hypertension International Protocol revision 2010 for the validation of blood pressure measuring devices in adults”. Methodology – The study involved 33 subjects, in each one of them, 9 sequential measurements of BP were performed, in the left arm, with the aneroid sphygmomanometer alternating with the automatic device. Afterwards, the differences on the values obtained by the different devices were evaluated, for systolic blood pressure (SBP) and diastolic (DBP), and these differences were then classified into three levels (≤ 5, ≤ 10 or ≤ 15 mmHg). The number of differences at each level was compared to the number required by the protocol (phase 1.1). For each subject the number of differences with values ≤ 5 mmHg was also determined. At least 24 of the 33 subjects should have 2 or 3 differences with values ≤ 5 mmHg and a maximum of 3 of the 33 subjects may have all differences with values > 5 mmHg (phase 1.2). Results – The device OMRON M6 Comfort ® was approved in phases 1.1 and 1.2 for SBP and DBP. The average difference between measurements of BP, as determined by automatic and manual devices, was -0.82 ± 5.62 mmHg for SBP and 2.14 ± 5.15 mmHg for DBP. Conclusion – The device OMRON M6 Comfort® is valid for measuring BP in adults, according to the ESH International Protocol of 2010.

Regulation of antioxidant enzymes gene expression in the yeast Saccharomyces cerevisiae during stationary phase

Gene expression of three antioxidant enzymes, Mn superoxide dismutase (MnSOD), Cu,Zn superoxide dismutase (Cu,ZnSOD), and glutathione reductase (GR) was investigated in stationary phase Saccharomyces cerevisiae during menadione-induced oxidative stress. Both GR and Cu,ZnSOD mRNA steady state levels increased, reaching a plateau at about 90 min exposure to menadione. GR mRNA induction was higher than that of Cu,ZnSOD (about 14-fold and 9-fold after 90 min, respectively). A different pattern of response was obtained for MnSOD mRNA, with a peak at about 15 min (about 8-fold higher) followed by a decrease to a plateau approximately 4-fold higher than the control value. However, these increased mRNA levels did not result in increased protein levels and activities of these enzymes. Furthermore, exposure to menadione decreased MnSOD activity to half its value, indicating that the enzyme is partially inactivated due to oxidative damage. Cu,ZnSOD protein levels were increased 2-fold, but MnSOD protein levels were unchanged after exposure to menadione in the presence of the proteolysis inhibitor phenylmethylsulfonyl fluoride. These results indicate that the rates of Cu,ZnSOD synthesis and proteolysis are increased, while the rates of MnSOD synthesis and proteolysis are unchanged by exposure to menadione. Also, the translational efficiency for both enzymes is probably decreased, since increases in protein levels when proteolysis is inhibited do not reflect the increases in mRNA levels. Our results indicate that oxidative stress modifies MnSOD, Cu,ZnSOD, and GR gene expression in a complex way, not only at the transcription level but also at the post-transcriptional, translational, and post-translational levels.

Q192R polymorphism of the paraoxonase-1 gene as a risk factor for obesity in Portuguese women

Introduction - Obesity became a major public health problem as a result of its increasing prevalence worldwide. Paraoxonase-1 (PON1) is an esterase able to protect membranes and lipoproteins from oxidative modifications. At the PON1 gene, several polymorphisms in the promoter and coding regions have been identified. The aims of this study were i) to assess PON1 L55M and Q192R polymorphisms as a risk factor for obesity in women; ii) to compare PON1 activity according to the expression of each allele in L55M and Q192R polymorphisms; iii) to compare PON1 activity between obese and normal-weight women. Materials and methods - We studied 75 healthy (35.9±8.2 years) and 81 obese women (34.3±8.2 years). Inclusion criteria for obese subjects were body mass index ≥30 kg/m2 and absence of inflammatory/neoplasic conditions or kidney/hepatic dysfunction. The two PON1 polymorphisms were assessed by real-time PCR with TaqMan probes. PON1 enzymatic activity was assessed by spectrophotometric methods, using paraoxon as a substrate. Results - No significant differences were found for PON1 activity between normal and obese women. Nevertheless, PON1 activity was greater (P<0.01) for the RR genotype (in Q192R polymorphism) and for the LL genotype (in L55M polymorphism). The frequency of allele R of Q192R polymorphism was significantly higher in obese women (P<0.05) and was associated with an increased risk of obesity (odds ratio=2.0 – 95% confidence interval (1.04; 3.87)). Conclusion - 55M and Q192R polymorphisms influence PON1 activity. The allele R of the Q192R polymorphism is associated with an increased risk for development of obesity among Portuguese Caucasian premenopausal women.