RESUMO Objetivo: Avaliar a homeostase dinâmica de tiol/dissulfureto e os níveis de malon dialdeído (MDA) e catalase (CAT) em pacientes com degeneração macular relacionada à idade (DMRI). Todas as análises foram realizadas em amostras de plasma. Métodos: Foram incluídos 32 pacientes com degeneração macular relacionada à idade e 38 controles saudáveis de idade similar. Os níveis de tiol, tiol total, dissulfureto e estado de homeostase de tiol/dissulfureto foram determinados utilizando um novo ensaio automatizado. Os níveis de atividade de MDA e CAT foram também determinados. As porcentagens foram comparadas pelo teste do qui-quadrado. O teste t de Student e o teste U de Mann Whitney foram utilizados para comparar variáveis quantitativas. Resultados: Os níveis de tiol nativo foram significativamente menores (p=0,004) nos pacientes com degeneração macular relacionada à idade (272,02 ± 52,41 µmol/l) do que nos indivíduos saudáveis (307,82 ± 47,18 µmol/l), enquan to os dissulfetos foram significativamente maiores em pacientes com degeneração macular relacionada à idade (21,64 ± 5,59 µmol/l versus 14,48 ± 5,37 µmol/l, respectivamente, p<0,001). A homeostase dinâmica de tiol/dissulfureto também foi significativamente menor nos pacientes com degeneração macular re la cionada à idade (13,41 ± 4,3 µmol/l) versus os controles (versus 25,41 ± 14,52 µmol/l, p<0,001). Não foram observadas diferenças significativas nos níveis de tiol total ou MDA. A atividade média de CAT foi significativamente mais elevada (p=0,043) em doentes com degeneração macular relacionada à idade (0,035 k/ml vs. 0,018 k/ml). Conclusões: O equilíbrio antioxidante/oxidante demonstrado pela homeostase dinâmica de tiol/dissulfeto é deslocado para o lado oxidativo em pacientes com de generação macular relacionada à idade.

ABSTRACT Purpose: We evaluated dynamic thiol/disulfide homeostasis (TDH), malondialdehyde (MDA) levels, and catalase (CAT) activity in patients with age-related macular degeneration (AMD). All analyzes were conducted on plasma samples. Methods: Thirty-two patients with AMD and 38 age-matched healthy controls were included. Native thiol, total thiol, and disulfide levels and TDH status were determined using a novel, automated assay. MDA levels and CAT activity were determined. Percentages were compared using the chi-squared test. The Student's t-test and Mann-Whitney U-test were used to compare quantitative variables. Results: Native thiol levels were significantly lower (p=0.004) in patients with AMD (272.02 ± 52.41 µmol/l) than in healthy individuals (307.82 ± 47.18 µmol/l), whereas disulfide levels were significantly higher (p<0.001) in patients with AMD than in controls (21.64 ± 5.59 vs. 14.48 ± 5.37 µmol/L). Dynamic TDH was also significantly lower (p<0.001) in patients with AMD than in controls (13.41 ± 4.3 vs. 25.41 ± 14.52 µmol/l). No significant differences were evident in total thiol or MDA levels. Mean CAT activity was significantly higher (p=0.043) in patients with AMD compared with controls (0.035 vs. 0.018 k/ml). Conclusions: The antioxidant/oxidant balance demonstrated by dynamic TDH is shifted to the oxidative side in patients with AMD.

Resumo Objetivo Investigar se os níveis de peptídeo natriurético pró-cerebral N-terminal (NTproBNP) refletem anormalidades no volume de líquido amniótico (VLA) em fetos normais. Métodos Reunimos 24 mulheres com oligoidrâmnios isolados, 23 com poli-hidrâmnios isolados, e 36 com VLA normal em um centro de referência. Comparamos os níveis de NT-proBNP em amostras venosas umbilicais e características individuais em três grupos. Usamos análise de variância simples (One-way ANOVA) e a análise de variação Kruskal-Wallis para comparação de variáveis contínuas em múltiplos grupos. Quando identificada uma diferença significativa, o teste de Scheffe foi aplicado como uma análise post-hoc. Comparamos proporções usando o teste Qui-quadrado (2). Resultados Idade fértil, índice de massa corporal, ganho de peso na gestação e níveis de NT-proBNP foram similares nos três grupos. Apgar em 1 e 5 minutos correlacionaram significativamente com os níveis de NT-proBNP em todos os recém-nascidos (Spearman's r = 0,23; p = 0,03 e Spearman's r = 0,24; p = 0,02, respectivamente). Os níves de NT-proBNP venoso umbilical não se distinguiram entre os recém-nascidos que precisaram de ventilação mecânica e aqueles que não precisaram (p = 0,595). Conclusões NT-proBNP é um candidato biomolecular que pode contribuir na patogênese de problemas circulatórios fetais e subsequente insuficiência renal. São necessárias futuras investigações.

Abstract Purpose The amniotic fluid volume (AFV) is known as a predictor for the wellness of a fetus. We aimed to investigate whether N-terminal pro-brain natriuretic peptide (NTproBNP) levels reflect AFV abnormalities in otherwise normal fetuses. Methods We recruited 24 women with isolated oligohydramnios, 23 women with isolated polyhydramnios, and 36 women with normal AFV at a tertiary referral center. NT-proBNP levels in umbilical venous samples and the individual characteristics of the three groups were compared. One-way ANOVA and Kruskal-Wallis analysis of variance were used for multi-group comparisons of continuous variables. When a significant difference was detected, the Scheffe test was performed as a post-hoc analysis. Proportions were compared using the Chi-square (2) test. Results Maternal age, body mass indices, weight gained in pregnancy and NT-proBNP levels were similar among the three groups. Apgar scores at 1 and 5 minutes significantly correlated with NT-proBNP levels in all newborns (Spearman's r = 0.23 ; p = 0.03 and Spearman's r = 0.24; p = 0.02, respectively). The umbilical venous NTproBNP levels did not differ between newborns who needed mechanical ventilation and those who didn't (p = 0.595). Conclusions NT-proBNP is a biomolecule that may provide insights into the pathogenesis of fetal circulatory problems and subsequent renal failure. Further investigations are warranted.

OBJECTIVES: To determine the serum and tissue levels of markers of impaired oxidative metabolism and correlate these levels with the histopathology and Alvarado score of acute appendicitis patients. METHOD: Sixty-five acute appendicitis patients (mean age, 31.4±12.06 years; male/female, 30/35) and 30 healthy control subjects were studied. The Alvarado score was recorded. Serum samples were obtained before surgery and 12 hours postoperatively to examine the total antioxidant status, total oxidant status, paraoxonase, stimulated paraoxonase, arylesterase, catalase, myeloperoxidase, ceruloplasmin, oxidative stress markers (advanced oxidized protein products and total thiol level) and ischemia-modified albumin. Surgical specimens were also evaluated. RESULTS: The diagnoses were acute appendicitis (n = 37), perforated appendicitis (n = 8), phlegmonous appendicitis (n = 12), perforated+phlegmonous appendicitis (n = 4), or no appendicitis (n = 4). The Alvarado score of the acute appendicitis group was significantly lower than that of the perforated+phlegmonous appendicitis group (p = 0.004). The serum total antioxidant status, total thiol level, advanced oxidized protein products, total oxidant status, catalase, arylesterase, and ischemia-modified albumin levels were significantly different between the acute appendicitis and control groups. There was no correlation between the pathological extent of acute appendicitis and the tissue levels of the markers; additionally, there was no correlation between the tissue and serum levels of any of the parameters. CONCLUSIONS: The imbalance of oxidant/antioxidant systems plays a role in the pathogenesis acute appendicitis. The Alvarado score can successfully predict the presence and extent of acute appendicitis.