Calcium homeostasis behavior and cardiac function on left ventricular remodeling by pressure overload

Sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) and sarcolemmal Na+/Ca2+ exchanger (NCX1) structures are involved in heart cell Ca2+ homeostasis. Previous studies have shown discrepancies in their function and expression in heart failure. The goal of this study was to evaluate heart function and hypertrophied muscle Ca2+-handling protein behavior under pressure overload. Twenty male Wistar rats were divided into two groups: Aortic stenosis (AoS), induced by a clip placed at the beginning of the aorta, and Control (Sham). After 18 weeks, heart function and structure were evaluated by echocardiogram. Myocardial function was analyzed by isolated papillary muscle (IPM) at basal condition and Ca2+ protein functions were evaluated after post-pause contraction and blockage with cyclopiazonic acid in IPM. Ca2+-handling protein expression was studied by western blot (WB). Echocardiogram showed that AoS caused concentric hypertrophy with enhanced ejection fraction and diastolic dysfunction inferred by dilated left atrium and increased relative wall thickness. IPM study showed developed tension was the same in both groups. AoS showed increased stiffness revealed by enhanced resting tension, and changes in Ca2+ homeostasis shown by calcium elevation and SERCA2a blockage maneuvers. WB revealed decreased NCX1, SERCA2a, and phosphorylated phospholambam (PLB) on serine-16 in AoS. AoS had left ventricular hypertrophy and diastolic dysfunction compared to Sham; this could be related to our findings regarding calcium homeostasis behavior: deficit in NCX1, SERCA2a, and phosphorylated PLB on serine-16.

Neonatal administration of citalopram delays somatic maturation in rats

We investigated the somatic maturation of neonate rats treated during the suckling period with citalopram, a selective serotonin reuptake inhibitor. Groups with 6 male neonates were randomly assigned to different treatments 24 h after birth. Each litter was suckled by one of the dams until the 21st postnatal day. Body weight, head axis and tail length were measured daily from the 1st to the 21st postnatal day. Time of ear unfolding, auditory conduit opening, incisor eruption, and eye opening was determined. Pups received 5 mg (Cit5), 10 mg (Cit10) or 20 mg/kg (Cit20) citalopram sc, or saline (0.9 percent NaCl, w/v, sc). Compared to saline, body weight was lower (24.04 percent, P < 0.01) for Cit10 from the 10th to the 21st day and for Cit20 from the 6th to the 21st day (38.19 percent, P < 0.01). Tail length was reduced in the Cit20 group (15.48 percent, P < 0.001) from the 8th to the 21st day. A reduction in mediolateral head axis (10.53 percent, P < 0.05) was observed from the 11th to the 21st day in Cit10 and from the 6th to the 21st day in Cit20 (13.16 percent, P < 0.001). A reduction in anteroposterior head axis was also observed in the Cit20 group (5.28 percent, P < 0.05) from the 13th to the 21stday. Conversely, this axis showed accelerated growth from the 12th to the 21stday in the Cit5 group (13.05 percent, P < 0.05). Auditory conduit opening was delayed in the Cit5 and Cit20 groups and incisor eruption was delayed in all citalopram groups. These findings show that citalopram injected during suckling to rats induces body alterations and suggest that the activity of the serotoninergic system participates in growth mechanisms.

Prevalência de carrapatos em cäes de áreas rurais da regiäo norte do Estado do Paraná / Prevalence of ticks on dogs from rural areas at northern region of Paraná

During January and February, 2000, 133 dogs from 21 farms located in eight diferent counties at the northern region of Paraná, Brazil, were examined for ticks. Ticks found on dogs were collected and identified. Information about dog rearing system was also obtained. Fifty-five ticks were collected on 19 dogs (14.3 per cent) from 11 farms (52.4 per cent). Four species were identified: Rhipicephalus sanguineus (20 ticks on nine dogs from seven farms), Boophilus microplus (15 ticks on five dogs from five farms), Amblyomma ovale (nine ticks on six dogs from four farms) and Amblyomma aureolatum (11 ticks on three dogs from one farm). The results are discussed considering the behavior of some dogs used to stroll into the woods and pasture areas whereas other dogs remained closer to the human facilities

Isolamento de Niocardia asteroides de lesäo granulomatosa em carne bovina / Isolation of Niocardia asteroides of granulomatous lesions in bovine meat

Os produtos de origem animal desempenham importante papel na alimentaçäo humana devido ao seu valor protéico, porém deve-se evitar que sirvam de vias de transmissäo de doenças aos seus consumidores. A interaçäo dinâmica entre o serviço de inspeçäo de carnes e as técnicas laboratoriais diagnósticas deve ser mantida na profilaxia das doenças veiculadas por alimentos. Relata um caso de contaminaçäo bacteriana de tecido muscular de bovino destinado ao consumo humano. Macroscopicamente observaram-se lesöes granulomatosas semelhantes àquelas associadas à tuberculose. Colheu-se 2,0g do material e, utilizando-se a técnica de descontaminaçäo de Petroff (OPS 1993), tentou-se o isolamento de Mycobacterium ssp, a partir dos meios de Lowenstein-Jensen e de Stonebrink-Lesslie a 37§C. Outro fragmento foi colhido e fixado em formol a 10 por cento para exame histopatológico. Após sete dias de cultivo observou-se no meio de Lowenstein-Jensen a presença de colônias rugosas com pigmento alaranjado. No exame bacteriológico observou-se micélios que se fragmentavam formando bacilos Gram positivos. No corte histológico, corado em Hematoxilina-Eosina, verificaram-se estruturas granulomatosas. Foi identificado Nocardia asteroides a partir das colônias isoladas. Estes microrganismos säo considerados saprófitas, telúricos capazes de causar infecçöes inicialmente pulmonares, disseminando-se posteriormente para outros órgäos, como: rins, baço, fígado, cérebro e ocasionalmente de desenvolver micetomas. Sem auxílio de profissionais integrados e capacitados para diagnosticar esta patologia, haveria maior risco para o consumidor. Conclui-se, portanto, que a crescente integraçäo entre os profissionais de saúde pública e saúde animal permite o aprimoramento das práticas diagnósticas e de prevençäo das zoonoses.

Tratamento com inibidor de recaptura de serotonina, no período neonatal, reduz agressividade intraespecífica em ratos adultos / Neonatal treatment with selectiv serotonin reuptake inihibitor reduces intraespecific aggression in rats

A maioria dos estudos sugerem que serotonina (5_HT) inibe agressão em ratos. O tratamento com inibidor de recaptura de serotonina aumenta sua disponibilidade sináptica no cérebro. Entretanto as consequências deste tratamento durante o período pós-natal sobre as respostas agressivas na vida adulta não são claras. No presente trabalho, os autores investigaram o comportamento agressivo de ratos adultos tratados com citalopram, um potente inibidor de recaptura de serotonina, durante o aleitamento. Os resultados indicaram que a administração repetida de citolopram no início da vida diminuiu o ganho de peso no período pós-natal e reduz o comportamento agressivo de ratos adultos