Javier Vargas Medrano

The present study is aimed to identify the effect of gratitude as an adaptive regulating mechanism from suicidal ideation (SI) for veterans with mental illness (study 1) and student veterans with posttraumatic stress disorder (PTSD) symptoms (study 2) in the United States. Descriptive statistics and regression analyses were used to examine sociodemographic characteristics and relationships between gratitude and SI. Our study 1 consisted of 156 veterans with mental illness. The mean age for study 1 was 37.85. Our study 2 consisted of 232 student veterans with PTSD symptoms. The mean age for study 2 was 28.43. Higher gratitude scores in study 1 and study 2 were significantly associated with lower SI scores after adjusting for demographics and depression. This study partially supports the association between gratitude and SI in veterans with mental illness. Based on the results from this study, gratitude interventions may be effective in reducing SI when working with veterans with mental illness.

1,2-Dichlorobenzene (1,2-DCB) is a benzene-derived molecule with two Cl atoms that is commonly utilized in the synthesis of pesticides. 1,2-DCB can be absorbed by living creatures and its effects on naturally-occurring enzymatic systems, including the effects on Ca2+-ATPases, have been poorly studied. Therefore, we aimed to study the effect of 1,2-DCB on the Ca2+-ATPase from sarcoplasmic reticulum (SERCA), a critical regulator of intracellular Ca2+ concentration. Concentrations of 0.05–0.2 mM of 1,2-DCB were able to stimulate the hydrolytic activity of SERCA in a medium-containing Ca2+-ionophore. At higher concentrations (0.25–0.75 mM), 1,2-DCB inhibited the ATP hydrolysis to ~80 %. Moreover, ATP hydrolysis and Ca2+ uptake in a medium supported by K-oxalate showed that starting at 0.05 mM,1,2-DCB was able to uncouple the ratio of hydrolysis/Ca2+ transported. The effect of this compound on the integrity of the SR membrane loaded with Ca2+ remained unaffected. Finally, the analysis of phosphorylation of SERCA by [γ-32P]ATP, starting under different conditions at 0° or 25 °C showed a reduction in the phosphoenzyme levels by 1,2-DCB, mostly at 0 °C. The temperature-dependent decreased levels of phosphoenzyme by 1,2-DCB could be due to the acceleration of the dephosphorylation mechanism – E2P · Ca2 state to E2 and Pi, which explains the uncoupling of the ATP hydrolysis from the Ca2+ transport.