A potent and selective activator of large-conductance Ca2+-activated K+ channels induces preservation of mitochondrial function after hypoxia and reoxygenation by handling of calcium and transmembrane potential.

AIMS: Ischaemic heart disease remains a significant cause of mortality globally. A pharmacological agent that protects cardiac mitochondria against oxygen deprivation injuries is welcome in therapy against acute myocardial infarction. Here, we evaluate the effect of large-conductance Ca2+-activated K+ channels (BKCa) activator, Compound Z, in isolated mitochondria under hypoxia and reoxygenation. METHODS: Mitochondria from mice hearts were obtained by differential centrifugation. The isolated mitochondria were incubated with a BKCa channel activator, Compound Z, and subjected to normoxia or hypoxia/reoxygenation. Mitochondrial function was evaluated by measurement of O2 consumption in the complexes I, II, and IV in the respiratory states 1, 2, 3, and by maximal uncoupled O2 uptake, ATP production, ROS production, transmembrane potential, and calcium retention capacity. RESULTS: Incubation of isolated mitochondria with Compound Z under normoxia conditions reduced the mitochondrial functions and induced the production of a significant amount of ROS. However, under hypoxia/reoxygenation, the Compound Z prevented a profound reduction in mitochondrial functions, including reducing ROS production over the hypoxia/reoxygenation group. Furthermore, hypoxia/reoxygenation induced a large mitochondria depolarization, which Compound Z incubation prevented, but, even so, Compound Z created a small depolarization. The mitochondrial calcium uptake was prevented by the BKCa activator, extruding the mitochondrial calcium present before Compound Z incubation. CONCLUSION: The Compound Z acts as a mitochondrial BKCa channel activator and can protect mitochondria function against hypoxia/reoxygenation injury, by handling mitochondrial calcium and transmembrane potential.

Photoproperties of favipiravir and its 6-substituted analogues: fluorescence controlled through halogen substitution and tautomerism.

Herein, we have showed the photophysical properties of favipiravir and its 6-substituted analogues. Also, we interpreted the origin of fluorescence of favipiravir and its 6-substituted analogues as a function of tautomerism modulation in ground and excited states. Favipiravir, the 6-fluorine derivative, showed the best photophysical profile, exhibiting a dominant emission wavelength of 430 nm, a high quantum yield (Q.Y.) of 1.0 and a long-lived state (10 ns). Its analogues also showed a maximum emission at 430 nm, but their Q.Y. values were 5-fold lower than that found for favipiravir, decreasing as a function of 6-substitution as follows: F > Cl > Br > I > H. Pyrazines bearing the least electronegative 6-substituent (X = Br, I, H) showed an extra lifetime, which was shorter (0.2-0.3 ns) and less abundant (>15%) than the main lifetime (10 ns, 85%). Further 2D excitation-emission matrix and solvent studies supported that these 3-hydroxy-2-pyrazinecarboxamides present two emissive states. The first of them (λem = 430 nm), which was the most abundant, most fluorescent and long-lived state, was characterized as "locally excited" (LE). Its fluorescence was favored with an increase of the hydrogen-donor nature of the solvent and for pyrazines having a high enolic characteristic. Thus, the high LE-fluorescence of these types of pyrazines depends on the keto-tautomerization of the ground state using a protic solvent and its feasible enol-tautomerization upon excitation. Finally, the second excited state (λem = 536 nm) was suggested as an excited-state intramolecular proton-transfer (ESIPT), and it was observed only, although discretely, for pyrazines bearing the least electronegative 6-substituent.

Perfil biossocial dos indivíduos portadores de doença de chagas atendidos no ambulatório de infectologia do Hospital Couto Maia, Salvador, Bahia / Biosocial profile of patients with chagas disease addmitted at the department of infectious diseases at Couto Maia Hospital, Salvador, Bahia / Perfil biosocial de los individuos portadores de la enfermedad de chagas atendidos en el ambulatorio de enfermedades infecciosas del hospital Couto Maia, Salvador, Bahia

A doença de Chagas é uma zoonose causada pelo protozoário Trypanosoma cruzi, endêmica nas Américas Central e do Sul. O presente estudo teve como objetivo avaliar o perfil biossocial dos pacientes portadores da Doença de Chagas Humana (DCH) atendidos no ambulatório de infectologia do Hospital Couto Maia, unidade de referência localizado em Salvador, Bahia. Trata-se de um estudo de corte transversal, descritivo, realizado de março a junho de 2012, com aplicação de questionário respondido em um único momento por doentesprovenientes de Itaberaba, Bahia. Os resultados evidenciam que, dentre os 28 pacientes estudados, 53,6por cento eram do sexo feminino, com idade de 38 a 84 anos; 42,9por cento eram analfabetos; 87,5por cento responderam receber menos que dois salários mínimos, sendo a agricultura a principalfonte de renda (nenhum paciente referiu ter carteira assinada); 78,6por cento tinham familiares com doença. Encontrou-se ainda a falta assistência sanitária, educação, moradia e saúde para a população estudada. Concluiu-se que a pesquisa pôde reforçar a sustentação dos dados daliteratura a respeito do perfil biossocial dos portadores da doença de Chagas.

Chagas disease is a zoonosis caused by the protozoan Trypanosoma cruzi, endemic in Central and South Americas. The present study aimed to evaluate the bio-social profile of patients with Chagas disease admitted at the Infectious Disease sector at Hospital Couto Maia, a reference hospital located in Salvador, Bahia. This research was conducted between March and June 2012, a questionnaire answered in a single moment was used as method with patients from Itaberaba, Bahia, Brazil. The results show that 28 patients 53.6percent of females aged 38-84 years, 42.9percent were illiterate, 87.5percent answered they received less than two minimum wages (agriculture was their main source of their income), none of the patientsmade any reference to full time jobs with contracts and 78.6percent of respondents has family and relatives affected by the Chagas disease. It can be concluded that this research can reinforce the literature data regarding the socio-cultural profile of patients with Chagas disease.Key words: Chagas disease. Social profile. Epidemiology.

La enfermedad de Chagas es una zoonosis causada por el protozooTrypanosoma cruzi, que es endémica en América Central y del Sur. Este estudio tuvo como objetivo evaluar el perfil biosocial de los pacientes portadores de la Enfermedad de Chagas humana (ECH), atendido en un ambulatorio de enfermedades infecciosas del Hospital Couto Maia, unidad de referencia localizado en Salvador, Bahia. Estudio de enfoque transversal, descriptivo, realizado de marzo a Junio de 2012, con la aplicación de cuestionario respondido en un único momento, por enfermos provenientes de Itaberaba, Bahia. Los resultados muestran que de los 28 pacientes, el 53,6por ciento eran mujeres, con edad entre 38 a 84 años; el42,9por ciento era analfabeto, el 87,5por ciento respondió que reciben menos de dos sueldos base, teniendo la agricultura como principal fuente de renta (ningún paciente refirió poseer registro formal de trabajo) y el 78,6por ciento de los encuestados estaban familiarizados con la enfermedad. Se encontró, aún, que la población estudiada carece de asistencia sanitaria, educación, habitación y salud. Se concluye que la investigación refuerza lo que sostenido por la literatura, con respecto al perfil biosocial de los portadores de la enfermedad de Chagas.