Progesterone reduces erectile dysfunction in sleep-deprived spontaneously hypertensive rats

BACKGROUND: Paradoxical sleep deprivation (PSD) associated with cocaine has been shown to enhance genital reflexes (penile erection-PE and ejaculation-EJ) in Wistar rats. Since hypertension predisposes males to erectile dysfunction, the aim of the present study was to investigate the effects of PSD on genital reflexes in the spontaneously hypertensive rat (SHR) compared to the Wistar strain. We also extended our study to examine how PSD affect steroid hormone concentrations involved in genital events in both experimental models. METHODS: The first experiment investigated the effects of PSD on genital reflexes of Wistar and SHR rats challenged by saline and cocaine (n = 10/group). To further examine the impact of the PSD on concentrations of sexual hormones, we performed a hormonal analysis of testosterone and progesterone in the Wistar and in SHR strains. Since after PSD progesterone concentrations decreased in the SHR compared to the Wistar PSD group we extended our study by investigating whether progesterone (25 mg/kg or 50 mg/kg) or testosterone (0.5 mg/kg or 1.0 mg/kg) administration during PSD would have a facilitator effect on the occurrence of genital reflexes in this hypertensive strain. RESULTS: A 4-day period of PSD induced PE in 50% of the Wistar rats against 10% for the SHR. These genital reflexes was potentiated by cocaine in Wistar rats whereas this scenario did not promote significant enhancement in PE and EJ in hypertensive rats, and the percentage of SHR displaying genital reflexes still figured significantly lower than that of the Wistar strain. As for hormone concentrations, both sleep-deprived Wistar and SHR showed lower testosterone concentrations than their respective controls. Sleep deprivation promoted an increase in concentrations of progesterone in Wistar rats, whereas no significant alterations were found after PSD in the SHR strain, which did not present enhancement in erectile responses. In order to explore the role of progesterone in the occurrence of genital reflexes, SHR were treated daily during the sleep deprivation period with progesterone; after the administration of this hormone and challenge with cocaine, we observed a significant increase in erectile events compared with the vehicle PSD SHR+cocaine group. CONCLUSION: Our data showed that the low frequency of genital reflexes found in SHR sleep deprived rats may be attributed to the lower concentrations of progesterone in these rats, based on the observation that progesterone replacement increased genital reflexes in this strain

Mechanical Analysis of Feeding Behavior in the Extinct “Terror Bird” Andalgalornis steulleti (Gruiformes: Phorusrhacidae)

The South American phorusrhacid bird radiation comprised at least 18 species of small to gigantic terrestrial predators for which there are no close modern analogs. Here we perform functional analyses of the skull of the medium-sized (∼40 kg) patagornithine phorusrhacid Andalgalornis steulleti (upper Miocene–lower Pliocene, Andalgalá Formation, Catamarca, Argentina) to assess its mechanical performance in a comparative context. Based on computed tomographic (CT) scanning and morphological analysis, the skull of Andalgalornis steulleti is interpreted as showing features reflecting loss of intracranial immobility. Discrete anatomical attributes permitting such cranial kinesis are widespread phorusrhacids outgroups, but this is the first clear evidence of loss of cranial kinesis in a gruiform bird and may be among the best documented cases among all birds. This apomorphic loss is interpreted as an adaptation for enhanced craniofacial rigidity, particularly with regard to sagittal loading. We apply a Finite Element approach to a three-dimensional (3D) model of the skull. Based on regression analysis we estimate the bite force of Andalgalornis at the bill tip to be 133 N. Relative to results obtained from Finite Element Analysis of one of its closest living relatives (seriema) and a large predatory bird (eagle), the phorusrhacid's skull shows relatively high stress under lateral loadings, but low stress where force is applied dorsoventrally (sagittally) and in “pullback” simulations. Given the relative weakness of the skull mediolaterally, it seems unlikely that Andalgalornis engaged in potentially risky behaviors that involved subduing large, struggling prey with its beak. We suggest that it either consumed smaller prey that could be killed and consumed more safely (e.g., swallowed whole) or that it used multiple well-targeted sagittal strikes with the beak in a repetitive attack-and-retreat strategy

Experience of taking care of children exposed to HIV: a trajectory of expectations

OBJETIVO: conhecer a experiência do cuidador/mãe em relação ao cuidado para com a criança exposta ao vírus da imunodeficiência humana por transmissão vertical, na trajetória pós-natal. MÉTODO: pesquisa qualitativa, que utilizou o Interacionismo Simbólico como referencial teórico. Foram realizadas entrevistas com 39 cuidadores de crianças expostas ao vírus da imunodeficiência humana e em seguimento em um serviço especializado. Os dados foram analisados pela análise de conteúdo indutiva. RESULTADOS: apreenderam-se quatro categorias que reportam à experiência solitária de manuseio da terapia antirretroviral da criança, no que se refere principalmente à ausência ou incompletude de informações recebidas; estar atento aos cuidados, que incluem o uso da profilaxia para pneumonia, vacinas e outros restritos à interação mãe/criança; querer omitir a presença do vírus da imunodeficiência humana pelo medo do preconceito e olhar o futuro e temer a doença. CONCLUSÃO: a presença do vírus da imunodeficiência humana e a ameaça dessa infecção na criança são capazes de gerar apreensão e tantos outros sentimentos como medo, culpa e ansiedade no cuidador. Os profissionais de saúde precisam trabalhar conjuntamente com a mãe para o enfrentamento das demandas e sofrimentos. Assim, o tratamento para evitar a transmissão vertical será eficiente e a mãe, juntamente à criança, viverá essa trajetória com apoio, apesar da apreensão pelo resultado.OBJETIVO: conocer la experiencia del cuidador/madre en relación al cuidado de niño expuesto al VIH por transmisión vertical en la trayectoria posnatal. MÉTODO: investigación cualitativa, que utilizó el Interaccionismo Simbólico como referencial teórico. Fueron realizadas entrevistas con 39 cuidadores de niños expuestos al VIH y que eran acompañados en un servicio especializado. Los datos fueron analizados por el análisis de contenido inductivo. RESULTADOS: se encontraron cuatro categorías que informan sobre la experiencia solitaria de la administración de la terapia antirretroviral del niño, en lo que se refiere principalmente a: la ausencia o a informaciones incompletas recibidas; al estar atento a los cuidados, que incluyen el uso de la profilaxis para neumonía, vacunas y otros restringidos a la interacción madre-niño; al querer omitir la presencia del VIH por miedo al prejuicio; y al mirar al futuro y temer a la enfermedad. CONCLUSIÓN: la presencia del VIH y la amenaza de infectar al niño son capaces de generar preocupación y varios otros sentimientos en el cuidador, como miedo, culpa y ansiedad. Los profesionales de la salud precisan trabajar conjuntamente con la madre para el enfrentamiento de las demandas y sufrimientos. Así, el tratamiento para evitar la transmisión vertical será eficiente y la madre con el niño vivirán esa trayectoria con apoyo, a pesar de la preocupación por el resultado.'OBJECTIVE: to learn about the experience of caregivers/mothers providing care to infants exposed to HIV through vertical transmission. METHODS: this qualitative study used Symbolic Interactionism as the theoretical framework. A total of 39 caregivers of children exposed to HIV in follow-up at a specialized service were interviewed. Data were analyzed through inductive content analysis. RESULTS: four categories were identified that report on the lonely experience of handling the child's antiretroviral therapy, mainly due to a lack of information or incomplete information; being attentive to required care, such as the use of prophylaxis for pneumonia, vaccines, and other practices restricted to the mother-child interaction; the desire to omit the HIV out of fear of prejudice and fear of the disease, considering future prospects. CONCLUSION: the HIV and the threat this infection may affect the child cause apprehension and feelings such as fear, guilt and anxiety in the caregivers. Healthcare workers need to work together with mothers so they are able to cope with demands and distress. Only then will the treatment to avoid vertical transmission be efficient and will mother and child be supported during the process, despite apprehension with the outcome