Vascular contraction of umbilical arteries of pregnant women with preeclampsia

Abstract Objective: Potassium channels have an important role in the vascular adaptation during pregnancy and a reduction in the expression of adenosine triphosphate-sensitive potassium channels (Katp) has been linked to preeclampsia. Activation of Katp induces vasodilation; however, no previous study has been conducted to evaluate the effects of the inhibition of these channels in the contractility of preeclamptic arteries. Glibenclamide is an oral antihyperglycemic agent that inhibits Katp and has been widely used in vascular studies. Methods: To investigate the effects of the inhibition of Katp, umbilical arteries of preeclamptic women and women with healthy pregnancies were assessed by vascular contractility experiments, in the presence or absence of glibenclamide. The umbilical arteries were challenged with cumulative concentrations of potassium chloride (KCl) and serotonin. Results: There were no differences between the groups concerning the maternal age and gestational age of the patients. The percentage of smokers, caucasians and primiparae per group was also similar. On the other hand, blood pressure parameters were elevated in the preeclamptic group. In addition, the preeclamptic group presented a significantly higher body mass index. The newborns of both groups presented similar APGAR scores and weights. Conclusion: In the presence of glibenclamide, there was an increase in the KCl-induced contractions only in vessels from the PE group, showing a possible involvement of these channels in the disorder.

Identification of inappropriate prescribing in a Brazilian nursing home using STOPP/START screening tools and the Beers' Criteria

The objective of this study was to determine the prevalence of Potentially Inappropriate Medication (PIM) use and associated factors, as well as the prevalence of Prescribing Omissions (PO). A cross-sectional study was conducted in a philanthropic Brazilian nursing home involving 46 individuals aged 60 years or older. The following information was collected from medical records and drug prescriptions: gender, age, health conditions and drugs used in the past thirty days. PIM and PO were identified according to the Beers' Criteria and the STOPP/START screening tools. Over one third (37%) of the population used at least one PIM according to the Beers' Criteria (n=17) and 60.9% according to the STOPP tool. A significant association was found between polypharmacy (use of five or more drugs) and use of PIM according to the Beers' Criteria, but not according to the STOPP. Eight residents (17.4%) were exposed to eight PO. This study allowed the diagnosis of a concerning drug utilization profile with use of a high number of PIMs. Thus, there is an evident need to implement strategies for improving geriatric prescription.

O objetivo deste estudo foi determinar a prevalência de uso de medicamentos potencialmente inadequados (MPI) e fatores associados, bem como a prevalência de omissões farmacoterapêuticas (OF). Trata-se de um estudo transversal realizado em uma instituição filantrópica brasileira de longa permanência com 46 indivíduos com 60 anos ou mais. As seguintes informações foram coletadas a partir de prontuários e prescrições: sexo, idade, condições de saúde e medicamentos utilizados nos últimos trinta dias. MPI e OF foram identificados pelo Critério de Beers e as ferramentas de triagem STOPP/START. Mais de um terço (37%) da população utilizou pelo menos, um MPI de acordo com os critérios de Beers (n=17) e 60.9% de acordo com a ferramenta STOPP. Associação estatisticamente significante foi detectada entre a polifarmácia (consumo de cinco ou mais medicamentos) e uso de MPI de acordo com os critérios de Beers, mas não de acordo com o STOPP. Oito residentes (17,4%) foram expostos a oito OF. Este estudo permitiu o diagnóstico de um perfil de utilização de medicamentos preocupante com número elevado de utilização de MPI. Isso indica a necessidade de implementar estratégias para melhorar a qualidade da prescrição geriátrica.

Papel do óxido nítrico na regulação da circulação pulmonar: implicações fisiológicas, fisiopatológicas e terapêuticas / Role of nitric oxide in the control of the pulmonary circulation: physiological, pathophysiological, and therapeutic implications

O nitric oxide (NO, óxido nítrico) é um mediador endógeno vasoativo que contribui para a homeostase vascular pulmonar. O NO é produzido por três isoformas das nitric oxide synthases (NOS, óxido nítrico sintases)-NOS neuronial (nNOS); NOS induzida (iNOS); e NOS endotelial (eNOS)-estando as três presentes no pulmão. Estudos que utilizaram inibidores farmacológicos ou camundongos knockout têm demonstrado que o NO derivado da eNOS desempenha importantes papéis ao modular o tônus vascular pulmonar e atenuar a hipertensão pulmonar. Por outro lado, estudos focados no papel da iNOS têm mostrado que essa isoforma contribui para a fisiopatologia da lesão pulmonar aguda e da síndrome do desconforto respiratório agudo. Esta revisão objetivou delinear o papel desempenhado pelo NO no controle da circulação pulmonar, tanto em condições fisiológicas como fisiopatológicas. Além disso, revisamos as evidências de que a via L-arginina-NO-guanosina monofosfato cíclico seja um importante alvo farmacológico para a terapia de doenças vasculares pulmonares.

Nitric oxide (NO) is an endogenous vasoactive compound that contributes to pulmonary vascular homeostasis and is produced by three nitric oxide synthase (NOS) isoforms-neuronal NOS (nNOS); inducible NOS (iNOS); and endothelial NOS (eNOS)-all three of which are present in the lung. Studies using pharmacological inhibitors or knockout mice have shown that eNOS-derived NO plays an important role in modulating pulmonary vascular tone and attenuating pulmonary hypertension. However, studies focusing on the role of iNOS have shown that this isoform contributes to the pathophysiology of acute lung injury and acute respiratory distress syndrome. This review aimed at outlining the role played by NO in the control of pulmonary circulation, both under physiological and pathophysiological conditions. In addition, we review the evidence that the L-arginine-NO-cyclic guanosine monophosphate pathway is a major pharmacological target in the treatment of pulmonary vascular diseases.