Effect of tobacco smoke on hydrogen sulfide-induced rat thoracic aorta relaxation

Levels of hydrogen sulfide (H2S), a gaseous signaling molecule, are reduced in the serum of individuals who smoke. We hypothesized that tobacco smoke influenced smooth muscle relaxation by decreasing H2S levels and this effect could also influence expression of cystathionine γ-lyase (CSE) and sulfonylurea receptor-2 (SUR-2). The aim of this study was to explore the effect of tobacco smoke on H2S-mediated rat thoracic aorta relaxation and its possible mechanism. Thirty-two Sprague-Dawley rats were divided into four groups: control (C) group, short-term smoker (SS) group, mid-term smoker (MS) group, and long-term smoker (LS) group. H2S concentrations in serum, action of H2S on rat aortic vascular relaxation, and expression of CSE and SUR-2 in thoracic aortic smooth muscle were measured. Although there was no significant difference in H2S between the C and the SS groups, concentration of H2S was significantly reduced in both the LS and MS groups compared to control (P<0.01). Furthermore, H2S was significantly lower in the LS than in the MS group (P<0.05). Rat aortic vascular relaxation was lower in all three treatment groups compared to the control, with the most significant decrease observed in the LS group (P<0.05 compared to the MS group). Expression of CSE and SUR-2 was reduced in the LS and MS groups compared to control (P<0.05), with the lowest levels observed in the LS group (P<0.05). Therefore, tobacco smoke reduced expression of CSE and SUR-2 in rat thoracic aorta, which may inhibit H2S production and vascular dilation.

Childhood sexual abuse among outpatients attending adult psychiatric outpatient clinics: a case-control study / Abuso sexual infantil entre los pacientes externos que asisten a las clínicas psiquiátricas ambulatorias para adultos: un estudio de caso-control

Only a few studies have focussed on the importance of routine investigation of childhood sexual abuse in outpatients attending adult psychiatric outpatient clinics. The aim of this study is to explore the association between having a history of childhood sexual abuse (CSA) and attending adult Psychiatric Outpatient Clinics in Trinidad. METHODS: This was a case-control study conducted in twelve psychiatric outpatient clinics located throughout Trinidad A questionnaire covering demographic, social, and sexual abuse components was administered by semi-structured interview to 566 participants, of whom 242 were cases, 239 were controls and 85 had incomplete questionnaires. The cases were 242 patients attending psychiatric outpatient clinics in Trinidad and the controls were 239 non-physician staffmembers at the clinics. Results were analyzed using the Stastistical Package for the Social Sciences (SPSS) version 10. RESULTS: Chi-square analyses revealed several significant differences between the cases and control group. Sixty-three (26%) cases and 29 (12.1%) controls experienced CSA (p < 0.000). Twenty-five (39.7%) of the CSA cases had their experiences between the ages of 4 to 8 years and 13 (44.8%) of the CSA controls had their experiences between the ages of 9 to 12 (p < 0.01). Twenty-six (41.3%) of the cases and 3 (10.3%) of the controls had been abused at least 5 times (p < 0.000). Seventeen (58.6%) abused CSA controls reported having been sexually abused as a child only once. CSA with both force and manipulation was reported by 30 (47.6%) CSA cases while 6 (20.7%) CSA controls experienced CSA with force and manipulation (p < 0. 025). The abused CSA cases reported having a smaller social network of 2 persons compared to the abused CSA controls who had a social network of more than 4 persons (p < 0. 05). Of the 92 abused participants, 73.9% were women, and only 52.2% had told someone about the CSA. For the majority of CSA cases and CSA controls, the abuse involved one abuser. CONCLUSION: A positive correlation was established between earlier onset of CSA, repeated abuse (occurring more than 5 times), a limited social network in patients who had CSA and attending adult psychiatric outpatient clinics. Identifying CSA in psychiatric outpatients may lead to early intervention and aid patient management.

Pocos estudios han centrado su atención en la importancia de la investigación de rutina en relación con el abuso sexual infantil en pacientes externos que asisten a las clínicas psiquiátricas ambulatorias para adultos. El objetivo del presente estudio es explorar la relación que existe entre poseer una historia de abuso sexual infantil (ASI) y asistir a las clínicas psiquiátricas ambulatorias para adultos en Trinidad. MÉTODOS: Se trató de un estudio de caso-control realizado en doce clínicas psiquiátricas para pacientes externos, diseminadas por toda Trinidad. Se administró un cuestionario que abarcaba componentes demográficos, sociales y sexuales, mediante entrevistas semi-estructuradas, a 566 participantes, de los cuales 242 fueron casos, 239 fueron controles, y 85 dejaron sus cuestionarios incompletos. Los casos fueron 242 pacientes que asistían a las clínicas externas de psiquiatría, y los controles fueron 239 miembros no médicos del personal en las clínicas. Los resultados fueron analizados usando la versión 10 del Paquete Estadístico para las Ciencias Sociales (SPSS). RESULTADOS: Los análisis de chi-cuadrado revelaron varias diferencias significativas entre los casos y el grupo de control. Sesenta y tres (26%) casos y 29 (12.1%) controles habían experimentado ASI (p < 0.000). Veinticinco (39.7%) de los casos de ASI tuvieron sus experiencias entre las edades de 4 a 18 años y 13 (44.8%) de los controles de ASI tuvieron sus experiencias entre las edades de 9–12 ( p < 0.01). Veintiséis (41.3%) de los casos y 3 (10.3%) de los controles habían sido víctimas de abuso por lo menos 5 veces (p < 0.000). Diecisiete (58.6%) de los controles víctimas de ASI, reportaron haber sido abusados sexualmente cuando niños, una sola vez. ASI con fuerza y manipulación, fue reportado por 30 (47.6%) casos de ASI mientras que 6 (20.7%) controles de ASi, experimentaron ASI con fuerza y manipulación (p < 0.025). Los casos de abuso de ASI, reportaron haber tenido una red social más pequeña de 2 personas, en comparación con los controles de abuso de ASI, que tenían una red social de más de 4 personas (p < 0.05). De los 92 participantes víctimas de abuso, 73.9% eran mujeres, y sólo 52.2% le habían contado a alguien sobre el ASI. Para la mayor parte de los casos de ASI y controles de ASI, en el abuso hubo un solo abusador implicado. CONCLUSIÓN: Se estableció una correlación positiva entre el comienzo más temprano del ASI, la repetición del abuso (que ocurría más de cinco veces), y una limitada red social en pacientes que fueron víctimas de ASI y asistían a las clínicas psiquiátricas ambulatorias. La identificación de ASI en pacientes psiquiátricos externos, puede conducir a una temprana intervención y tratamiento de ayuda al paciente.