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171.
Gonadotropins and Growth Hormone Family Characterization in an Endangered Siluriform Species,Steindachneridion parahybae (Pimelodidae): Relationship With Annual Reproductive Cycle and Induced Spawning in Captivity
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Renato Massaaki Honji Danilo Caneppele Matias Pandolfi Fabiana Laura Lo Nostro Renata Guimarães Moreira 《Anatomical record (Hoboken, N.J. : 2007)》2015,298(9):1644-1658
The aim of this study was to identify and characterize pituitary cells of Steindachneridion parahybae females in captivity, highlighting the possible relationship with reproductive disorders at this level, since this species shows oocyte final maturation, ovulation and spawning dysfunction in captivity. The localization and distribution of growth hormone (GH), prolactin (PRL), somatolactin (SL), β‐luteinizing hormone (β‐LH), and β‐follicle stimulating hormone (β‐FSH) immunoreactive (‐ir) cells in the adenohypophysis was studied by immunohistochemical and Western blot methods. In addition, cellular morphometric analyses and semi‐quantification of ir‐cells optical density (OD) during the annual reproductive cycle and after artificial induced spawning (AIS) were performed. Results showed that the distribution and general localization of pituitary cell types were similar to that of other teleost species. However, the morphometrical study of adenohypophysial cells showed differences along the reproductive cycle and following AIS. In general, females at the vitellogenic stage presented greater OD values for GH, PRL and SL than at other maturation stages (previtellogenic and regression stages), probably indicating an increased cellular activity during this stage. Conversely, β‐LH OD did not vary during the annual reproductive cycle. After AIS, β‐LH, SL and GH ir‐cells showed an increase in OD values suggesting a possible involvement on oocyte final maturation, ovulation and spawning or a feedback control on the brain‐pituitary‐gonads axis. Reproductive dysfunction in S. parahybae females in captivity may be due to alteration of the synthesis pathways of β‐LH. In addition, GH family of hormones could modulate associated mechanisms that influence the reproductive status in this species. Anat Rec, 298:1644–1658, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
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Joycellane Alline do Nascimento Campos Ribeiro Alexandre Coellho Serquiz Priscila Fabíola dos Santos Silva Patrícia Batista Barra Medeiros Barbosa Tarcísio Bruno Montenegro Sampaio Raimundo Fernandes de Araújo Junior Adeliana Silva de Oliveira Richele Janaina Araújo Machado Bruna Leal Lima Maciel Adriana Ferreira Uch?a Elizeu Antunes dos Santos Ana Heloneida de Araújo Morais 《Clinics (S?o Paulo, Brazil)》2015,70(2):136-143
OBJECTIVES:
Seeds are excellent sources of proteinase inhibitors, some of which may have satietogenic and slimming actions. We evaluated the effect of a trypsin inhibitor from Tamarindus indica L. seeds on weight gain, food consumption and cholecystokinin levels in Wistar rats.METHODS:
A trypsin inhibitor from Tamarindus was isolated using ammonium sulfate (30–60%) following precipitation with acetone and was further isolated with Trypsin-Sepharose affinity chromatography. Analyses were conducted to assess the in vivo digestibility, food intake, body weight evolution and cholecystokinin levels in Wistar rats. Histological analyses of organs and biochemical analyses of sera were performed.RESULTS:
The trypsin inhibitor from Tamarindus reduced food consumption, thereby reducing weight gain. The in vivo true digestibility was not significantly different between the control and Tamarindus trypsin inhibitor-treated groups. The trypsin inhibitor from Tamarindus did not cause alterations in biochemical parameters or liver, stomach, intestine or pancreas histology. Rats treated with the trypsin inhibitor showed significantly elevated cholecystokinin levels compared with animals receiving casein or water.CONCLUSION:
The results indicate that the isolated trypsin inhibitor from Tamarindus reduces weight gain by reducing food consumption, an effect that may be mediated by increased cholecystokinin. Thus, the potential use of this trypsin inhibitor in obesity prevention and/or treatment should be evaluated. 相似文献173.
Giovanna Cilluffo Giuliana Ferrante Renato Cutrera Giorgio Piacentini Elisabetta Bignamini Massimo Landi Paola Martucci Luigi Morcaldi Fabio Midulla Giovanni Viegi Stefania La Grutta 《Journal of thoracic disease》2020,12(11):6868
BackgroundPaediatricians rarely devote any time to screening and treatment for parental tobacco use. The present project is part of a Global Alliance against Chronic Respiratory Diseases (GARD)-Italy Demonstration Project, aimed to increase the skills of primary care physicians and paediatricians as “promoter of smoking cessation”. The aims of this study were: (I) to identify latent classes of barriers and incentives for smoking cessation counseling among paediatricians using latent class analysis (LCA); (II) to investigate risk factors for inclusion into the identified classes.MethodsIn 2018, 1,500 Italian paediatricians were invited to complete an online survey on passive smoke exposure in children. LCA was used to discover underlying response patterns, and to identify respondent groups with similar attitudes toward passive smoke exposure in children. Multinomial logistic regression helped investigate which explanatory variables influenced inclusion into a class. A P value <0.05 was considered significant.ResultsThe overall response rate was 71% (n=1,071/1,500). Three classes were identified: Class 1 “passive” (n=226, 21.10%); Class 2 “unmotivated” (n=124, 11.58%); and Class 3 “proactive” (n=721, 67.32%). Assuming Class 3 as reference, ever having been a smoker was borderline associated (P=0.052) with increased probability of inclusion into Class 1 (OR =1.43, 95% CI, 1.00–2.06). Having 6–15 or ≥15 years of work experience versus having less than five years was associated with decreased probability of being in the “passive” class (OR =0.46, 95% CI, 0.22–0.96 and OR =0.49, 95% CI, 0.27–0.87, respectively), as was discussing parents’ addiction to alcohol/drugs (OR =0.50, 95% CI, 0.33–0.76).ConclusionsWe identified three profiles among Italian paediatricians related to barriers and incentives for smoking cessation promotion. Tailored educational interventions for paediatricians are required to promote smoking cessation programs. 相似文献
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Renato Graciano de Paula Alice Maria de Magalhães Ornelas Enyara Rezende Morais William de Castro Borges Massimo Natale Lizandra Guidi Magalhães Vanderlei Rodrigues 《Parasitology research》2014,113(8):2887-2897
The trematode Schistosoma mansoni, an important parasite of humans, is the principle agent of the disease schistosomiasis. In the human host, one of the most important stress factors of this parasite is the oxidative stress generated by both the metabolism of the worm and the immune system of the host. The proteasomal system is responsible for protein homeostasis during oxidative stress. The 26S proteasome is a multicatalytic protease formed by two compartments, a 20S core and regulatory particle 19S, and controls the degradation of intracellular proteins, hence regulating many cellular processes. In the present report, we describe the biochemical characterization and role of the 20S proteasome in the response of adult S. mansoni worms exposed to hydrogen peroxide. Characterization of the response to the oxidative stress included the evaluation of viability, egg production, mortality, tegument integrity, and both expression and activity of proteasome. We observed decreases in viability, egg production as well as 100 % mortality at the higher concentrations of hydrogen peroxide tested. The main changes observed in the tegument of adult worms were peeling as well as the appearance of bubbles and a decrease of spines on the tubercles. Furthermore, there were increases in 26S activity to the same extent as 20S proteasome activity, although there was increase of 20S proteasome content, suggesting that degradation of protein oxidized in adult worms is due to the 20S proteasome. It was demonstrated that adult S. mansoni worms are sensitive to oxidative stress, and that a variety of processes in this parasite are altered under this condition. The work contributes to a better understanding of the mechanisms employed by S. mansoni to survive under oxidative stress. 相似文献
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Ama Z. S. Rohatiner Matthew L. Smith Orietta Spinelli Alessandro Rambaldi Renato Bassan Eros di Bona Francesco Rodeghiero Roberto Raimondi Magnus Björkholm Steve Johnson Adrian C. Newland Jamie D. Cavenagh Finlay Macdougall Rachel Waters Jude Fitzgibbon Tiziano Barbui Andrew Lister 《British journal of haematology》2014,167(5):724-726
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