A comparative study of cytoarchitecture and serotonergic afferents in the suprachiasmatic nucleus of primates (Cebus apella and Callithrix jacchus) and rats (Wistar and Long Evans strains)

The suprachiasmatic nucleus, an essential diencephalic component of the circadian timing system, plays a role in the generation and modulation of behavioral and neuroendocrine rhythms in mammals. Its cytoarchitecture, neurochemical and hodological characteristics have been investigated in various mammalian species, particularly in rodents. In most species, two subdivisions, based on these aspects and considered to reflect functional specialization within the nucleus, can be recognized. Many studies reveal a typical dense innervation by serotonergic fibers in this nucleus, mainly in the ventromedial area, overlapping the retinal afferents. However, a different pattern occurs in certain animals, which lead us to investigate the distribution of serotonergic afferents in the suprachiasmatic nucleus of the Capuchin monkey, Cebus apella, compared to the marmoset, Callithrix jacchus, and two Rattus norvegicus lines (Long Evans and Wistar), and to reported findings for other mammalian species. Our morphometric data show the volume and length of the suprachiasmatic nucleus along the rostrocaudal axis to be greatest in C. apella > C. jacchus > Long Evans ≥ Wistar rats, in agreement with their body sizes. In C. apella, however, the serotonergic terminals occupy only some 10% of the nucleus' area, less than the 25% seen in the marmoset and rats. The distribution of the serotonergic fibers in C. apella does not follow the characteristic ventral organization pattern seen in the rodents. These findings raise questions concerning the intrinsic organization of the nucleus, as well as regarding the functional relationship between serotonergic input and retinal afferents in this diurnal species. © 2007 Elsevier B.V. All rights reserved.

Alterações reprodutivas em ratos machos expostos perinatalmente aos frutos da Solanum lycocarpum

This work employed pregnant rats treated with Solanum lycocarpum unripe fruits (10% in diet) from gestation day (GD) 06 to post-natal day (PND) 07, for the evaluation of the sperm number, daily sperm production and epididymal sperm transit time of the male offspring at PND 60 and PND 90. No differences were observed in the daily sperm production (DSP) and sperm number in the testis of the exposed males at PND 60 and PND 90. Also, no alterations were observed in sperm transit time in the caput epididymis of the exposed males at PND 60 and PND 90. However, a reduced sperm transit time was observed in the corpus/cauda epididymis of the experimental males at PND 90. The last data may explain the reduced sperm number observed in the corpus/cauda epididymis of the experimental male rats at PND 90. These data show that the male rats exposed to S. lycocarpum fruits during gestation did not present alterations in testis sperm production and number, however the sperm transit time through epididymis was impaired, resulting in a decreased number of spermatozoa in epididymis cauda. We conclude that S. lycocarpum may cause imbalance on hypothalamus-pituitary gland axis.

Perinatal exposure to parasiticide ivermectin: Long-term effects on reproductive parameters of adult male rats

Ivermectin is one of the most widely used antiparasitic drugs globally. The aim of this study was to evaluate the chronic effects of perinatal exposure to ivermectin on male reproductive parameters in rats. Pregnant rats were treated daily by oral gavage with 0.4 or 1.6 mg kg -1 of ivermectin or vehicle, from gestational day 6 until post-natal day 10. In the adulthood stage, there were significant reductions in the relative testicular weight of rats exposed to the low dose and in relative prostate weight of male rats exposed to the high dose of ivermectin. Furthermore, the animals exposed to the low dose also presented an increased seminal vesicle weight compared to controls. However, neither of the ivermectin doses interfered in daily sperm production, sperm number in testis, or sexual behavior of exposed males. In conclusion, perinatal exposure to ivermectin neither altered the male reproductive system development markedly, nor produced any adverse effects on the parameters evaluated. © 2011 Taylor & Francis.

Changes in facial morphology after adenotonsillectomy in mouth-breathing children

Background. Morphological and dentofacial alterations have been attributed to impaired respiratory function. Objective. To examine the influence of mouth breathing (MB) on children facial morphology before and after adenoidectomy or adenotonsillectomy. Methods. Thirty-three MB children who restored nasal breathing (NB) after surgery and 22 NB children were evaluated. Both groups were submitted to lateral cephalometry, at time 1 (T1) before and at time 2 (T2) 28months on average postoperatively. Results. Comparison between the MB and NB groups at T1 showed that mouth breathers had higher inclination of the mandibular plane; more obtuse gonial angle; dolichofacial morphology; and a decrease in the total and inferior posterior facial heights. Twenty-eight months after the MB surgical intervention, they still presented a dolichofacial morphologic pattern. During this period, MB altered the face growth direction and decreased their mandible plane inclination, with reduction in the SN.GoGn, PP.MP, SNGn, and ArGo.GoMe parameters as well as an increase in BaN.PtGn. Conclusion. After the MB rehabilitation, children between 3 and 6years old presented significant normalization in the mandibular growth direction, a decrease in the mandible inclination, and an increase in the posterior facial height. Instead, they still persisted with a dolichofacial pattern when compared with nasal breathers. © 2011 The Authors. International Journal of Paediatric Dentistry © 2011 BSPD, IAPD and Blackwell Publishing Ltd.

Soroprevalência de anticorpos contra Leishmania infantum e outras espécies de protozoários e rickettsia em cães

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Slimmer or Fertile? Pharmacological Mechanisms Involved in Reduced Sperm Quality and Fertility in Rats Exposed to the Anorexigen Sibutramine

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Androgen deprivation from pre-puberty to peripuberty interferes in proteins expression in pubertal and adult rat epididymis

Few studies have focused on experimental testosterone deprivation in immature animals. Therefore, this study used sexually immature rats aiming to evaluate the testes and epididymis histology and proteins expression in these organs on PND50 and 75, after premature antiandrogen exposure, from PND21 to 44. Although the androgen deprivation from pre-puberty up to peripuberty did not alter the histological organization of the testes and epididymis either at puberty or at adulthood, the treatment impaired the expression of specific proteins in epididymal tissue at puberty and adulthood (androgen receptor, calmodulin, Rab11A). These changes may be related to impaired epididymal function, sperm quality and fertility capacity as observed in a previous study. Further studies are necessary to better investigate the molecular mechanisms involved in the impairment on reproductive competence of male rats after precocious hormonal injury. © 2013 Elsevier Inc.

Morphology and initial growth in the germination of dictyosperma album (bory) h. wendl. & drude ex scheffer (Arecaceae) seeds

Dictyosperma album, commonly known as Princess Palm, due to its graceful appearance and its ability to withstand strong hurricane force winds is largely used in landscaping areas. The aim of this work was to describe the diaspores (seeds with the stuck endocarp) morphology and the stages of the D. album germination process. Therefore we concluded that the species germination is of the tubular remote type and begins with the opening of a circular operculum in the fruit endocarp, through which emerges a bulbous and hollow structure, named cotyledonal petiole or embryophore. With the embryo growth, the endosperm is being gradually consumed. The embryo grows approximately up to 10 cm, when the dilation begins in its extremity. Starting from this extensive area, it begins the growth of the primary root and the opening of a longitudinal rift, through which emerges the aerial part that is composed by two sheaths that cover the first juvenile leaf. In this phase, the emergence of secondary roots is observed. The first leaves are simple and lance-shaped.

Excess androgen during perinatal life alters steroid receptor expression, apoptosis, and cell proliferation in the uteri of the offspring

Exposure to environmental chemicals may contribute to reproductive disorders, especially when it occurs in critical periods of development. The female reproductive system can be a target for androgens derived from environmental contaminants or pathological conditions. The purpose of this study was to assess the long-term effects of androgens on uterine tissue after maternal exposure limited to the time of gestation and lactation. Pregnant Wistar rats were treated with testosterone propionate (TP) at 0.05. mg/kg, 0.1. mg/kg, 0.2. mg/kg or corn oil (vehicle), s.c., from gestational day 12 until the end of lactation. The results show changes in the pattern of expression of receptors for estrogen, progesterone, and androgen at all doses tested, and decreases in both apoptosis and cell proliferation indices at 0.1 and 0.2. mg/kg. We conclude that early TP exposure, under these experimental conditions, causes changes in cellular and molecular parameters that are essential for normal uterine function in the adult. © 2013 Elsevier Inc.

A comunicação da informação em sites noticiosos regionais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

I Workshop on Male Reproductive Biology

Proceedings of the I Workshop on Male Reproductive Biology carried out in Brazil, from November 05 to 07, 2007.

Robinson Crusoé, o único livro de Emílio

O artigo investiga os fundamentos do processo de leitura presente no Emílio, de Rousseau, de acordo com os princípios de utilidade e necessidade que sustentam esse “romance educativo”. O Robinson Crusoé, de Daniel Defoe, único livro recomendado pelo preceptor de Emílio, é analisado segundo a perspectiva da educação do “homem natural”. Palavras-chave: Rousseau; leitura; educação; Robinson Crusoé.

As formas hesitantes: a alomorfia na formação do plural dos substantivos em alemão

Analisam-se neste trabalho as ocorrências das chamadas Schwankungen un Doppelformen (formas variantes e formas duplas) enquanto manifestação da escolha subjetiva do falante da língua. Aponta-se para a contaminação do plano morfológico pela ambigüidade criada por essas mesmas formas variantes, resultando, por exemplo, nos diversos alomorfes do caso plural em alemão. Através do arcabouço teórico de E. Nida (1967), pretende-se averiguar a possibilidade de condicionamento nas diversas realizações do plural dos substantivos em alemão.

Perinatal Androgenic Exposure and Reproductive Health Effects Female Rat Offspring

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Serology, isolation, and molecular detection of Leptospira spp. from the tissues and blood of rats captured in a wild animal preservation centre in Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)