The effect of low dose ionizing radiation exposure on dynamic thiol-disulfide homeostasis and ischemia modified albumin levels: an observational study / Efeito da exposição à radiação ionizante de baixa dose na homeostase dinâmica de tiol-dissulfeto e níveis de albumina modificada por isquemia: estudo observacional

Abstract Background: The primary objective of this study was to investigate the effect of low dose ionizing radiation exposure on thiol/disulfide homeostasis and ischemia modified albumin levels. The secondary objective is to compare thiol/disulfide homeostasis and ischemia modified albumin levels among the personnel exposed to low dose ionizing radiation in anesthesia application areas, in and out of the operation room. Methods: The study included a total of 90 volunteers aged between 18 and 65 years old, with 45 personnel working in a setting with potential for radiation exposure (Exposed Group) and 45 personnel in a setting without radiation exposure (Control Group). Their native thiol, total thiol, disulphide, albumine and IMA levels were measured. Exposed group included personnel who were exposed to radiation outside the operating room - Operation room (−) Group and inside the operating room - Operation room (+) Group. Results: Albumin, native and total thiol levels were significantly lower in the participants exposed to radiation in the anesthesia application area; no statistically significant difference was found in terms of disulfide and ischemia modified albumin levels. In the Operation room (−) Group exposed to radiation, native thiol and total thiol values were significantly lower compared to the Operation room (+) Group. Conclusion: Awareness of being in danger of oxidative stress should be established in personnel exposed to radiation in the anesthesia application area following low dose ionizing radiation exposure, and the necessary measures should be taken.

Resumo Justificativa: O objetivo principal do estudo foi investigar o efeito de exposição à radiação ionizante de baixa dose nos níveis de homeostase tiol/dissulfeto e de albumina modificada por isquemia. O objetivo secundário foi comparar os níveis de homeostase tiol/dissulfeto e albumina modificada por isquemia entre indivíduos expostos à radiação ionizante de baixa dose nas áreas de procedimentos anestésicos, dentro e fora da sala de cirurgia. Método: O estudo incluiu um total de 90 voluntários com idades entre 18 e 65 anos, 45 profissionais que trabalhavam em ambiente de exposição potencial a radiação (Grupo Exposto) e 45 profissionais que trabalhavam em ambiente sem exposição à radiação (Grupo Controle). Foram medidos os níveis de tiol nativo, tiol total, dissulfeto, albumina e albumina modificada por isquemia. O Grupo Exposto era constituído por profissionais expostos a radiação fora da sala de cirurgia - Grupo sala de cirurgia (-) e na sala de cirurgia - Grupo sala de cirurgia (+). Resultados: Os níveis de albumina, tiol nativo e total foram significantemente mais baixos nos participantes expostos à radiação em área de realização de anestesia, e nenhuma diferença estatisticamente significante foi encontrada para os níveis de dissulfeto e albumina modificada por isquemia. No Grupo exposto sala de cirurgia (-), os valores de tiol nativo e tiol total foram significantemente mais baixos quando comparados ao Grupo sala de cirurgia (+). Conclusões: Os profissionais expostos à radiação em área de realização de anestesia devem ser conscientizados quanto ao perigo do estresse oxidativo após exposição à radiação ionizante de baixa dose e medidas cabíveis devem ser instituídas.

The effect of continuous ventilation on thiol-disulphide homeostasis and albumin-adjusted ischemia-modified albumin during cardiopulmonary bypass

Abstract Objective: To investigate the effect of continuous lung ventilation with low tidal volume on oxidation parameters, such as thiol/disulphide homeostasis and albumin-adjusted ischemia-modified albumin (AAIMA), during cardiopulmonary bypass (CBP) in coronary artery bypass grafting (CABG). Methods: Seventy-four patients who underwent elective CABG with CPB were included in the study. Blood samples were taken in the preoperative period, 10 minutes after CPB, and six and 24 hours postoperatively. Patients were assigned to the continuous ventilation group (Group 1, n=37) and the non-ventilated group (Group 2, n=37). The clinical characteristics, thiol/disulphide homeostasis, ischemia-modified albumin (IMA), and AAIMA levels of the patients were compared. Results: A significant difference was found between the groups regarding native thiol, total thiol, and IMA levels at the postoperative 24th hour (P=0.030, P=0.031, and P=0.004, respectively). There was no difference between the groups in terms of AAIMA. AAIMA levels returned to preoperative levels in Groups 1 and 2, at the 6th and 24th postoperative hours, respectively. Length of hospital stay was significantly shorter in Group 1 (P<0.001) than in Group 2. Conclusion: Continuous ventilation during CPB caused an increase in native and total thiol levels, an earlier return of AAIMA levels, and shorter hospital stay. Continuous ventilation may reduce the negative effects of CPB on myocardium (Table 2, Figure 1, and Reference 31).

Role of native thiol, total thiol and dynamic Disulphide in diagnosis of patient with prostate cancer and prostatitis

ABSTRACT Background: Our study investigates whether Native Thiol, Total Thiol and disulphide levels measured in serum of patients with prostate cancer and prostatitis and of healthy subjects, have any role in differential diagnosis. Materials and Methods: Patients followed up for histopathologically verified diagnosis of prostate cancer and prostatitis in 2016-2017 at the Medicalpark Gaziantep Hospital Urology Clinic were included in the study. Native Thiol (NT), Total Thiol (TT), Dynamic Disulphide (DD) levels in serum were measured by a novel automated method. Results: NT, TT, DD, NT / TT ratios, DD / TT ratio and DD / NT ratio were measured as 118.4 ± 36.8μmoL / L, 150.3 ± 45.3μmoL / L, 15.9 ± 7μmoL / L, 78.8 ± 7μmoL / L, 10.5 ± 3.5μmoL / L, 13.8 ± 5.8μmoL / L respectively in patients with prostate cancer; as 116.4 ± 40.5μmoL / L, 147.5 ± 50.1μmoL / L, 15.5 ± 8.7μmoL / L, 79.7 ± 9μmoL / L, 10.1 ± 4.5μmoL / L, 13.5 ± 7.2μmoL / L in patients with prostatitis and as 144.1 ± 21.2μmoL / L, 191 ± 32.3μmoL / L, 23.4 ± 10.1μmoL / L, 76.1 ± 98.3μmoL / L, 11.9 ± 4.1μmoL / L, 16.4 ± 6.9μmoL / L in healthy subjects. Significant difference was detected between groups of NT, TT and DD levels (p = 0.008, p = 0.001, p = 0.002). No significant difference was detected in terms of the NT / TT, DD / TT and DD / NT rates (p = 0.222, p = 0.222, p = 0.222). Conclusions: Serum NT, TT, DD levels in patients with prostatitis and prostate cancer were found significantly lower compared to the control group. This indicates that just as inflammation, prostate cancer also increases oxidative stress on tissues.

Dynamic thiol/disulfide homeostasis in patients with age-related macular degeneration / Homeostase dinâmica de tiol/dissulfureto em pacientes com degeneração 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: 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.

The effects of ozone on bacterial growth and thiol-disulphide homeostasis in vascular graft infection caused by MRSA in rats

Abstract: Purpose: To investigate the microbiological, inflammatory and oxidant effects of adjuvant ozone administration in experimental rat vascular graft infection model which has not been previously investigated. Methods: Forty adult Wistar rats were divided into Sham, Control, Vancomycin, Ozone, Vancomycin+Ozone groups. Grafts were inoculated with Methicillin-resistant Staphylococcus aureus (MRSA) strain and implanted subcutaneously. Rats were treated intraperitoneally with ozone and /or intramuscularly with vancomycin for 10 days. Grafts were evaluated by quantitative bacterial cultures. Blood samples were harvested for determination of thiol-disulphide and cytokine profiles. Results: There was no significant difference in bacterial counts between Control and Ozone Groups. In the Ozone Group median colony count was significantly higher than the Vancomycin and Vancomycin+Ozone Groups. Total thiol and disulphide levels increased and disulphide/native thiol and disulphide/total thiol ratios decreased in Ozone Group significantly. Albumin levels decreased significantly in Vancomycin and Vancomycin+Ozone Groups compared to the Sham Group. IL-1 and TNF-alpha levels significantly increased in infected rats. Decreased levels of VEGF due to infection reversed by ozone therapy in control and vancomycin groups. Conclusions: We didn't observe any benefit of the agent on MRSA elimination in our model. Likewise, effects of ozone on thiol-disulphide homeostasis and inflammatory cytokines were contradictory.

Pharmacokinetic aspects of Tert-Butylaminoethyl disulfide, an experimental drug against schistosomiasis in mice

Um estudo preliminar da farmacocinética do t-butilamino-etil-dissulfeto foi conduzido utilizando droga fria ou radioativa em duas diferentes doses (35 e 300 mg/Kg). Amostras de plasma ou sangue foram tratadas com ditiotreiol, ácido perclórico, e, após filtraçäo, submetidas a uma subseqüente purificaçäo em um "batch" de resina aniônica. Na etapa final, a droga foi retida em coluna de resina catiônica, eluída com NaCl 1 M e detectada pelo método de Ellman (1958). Alternativamente, a droga radioativa foi detectada por cintilaçäo líquida. Os resultados correspondentes a droga total administrada na menor dose sugeriram um comportamento farmacocinético relacionado ao modelo de um compartimento aberto, com os seguintes parâmetros: área sob a curva intravenosa (ASCI.V.): 671 ñ 14; ASCoral: 150 ñ 40 microng.min.ml-1; constante de eliminaçäo: 0,07 min-1; meia-vida biológica: 9,8 min; volume de distribuiçäo: 0,74 ml/g. Para a dose mais alta, os resultados indicaram aparentemente a ocorrência de um modelo mais complexo e näo adequadamente classificado. Analisados em conjunto os resultados sugerem a ocorrência de um comportamento farmacocinético dose-dependente. A droga é absorvida e eliminada rapidamente, sendo este último processo relacionado principalmente a metabolizaçäo. A droga parece mais tóxica quando administrada via I.V. porque por esta via ela näo sobre metabolismo de primeira passagem e, é, por outro lado rapidamente distribuída para os tecidos. O nível sanguíneo máximo tolerado pelos animais parece ser de 16 microng/ml