Androgen receptor immunoreactivity in forebrain axons and dendrites in the rat

As members of the steroid receptor superfamily, androgen receptors (ARs) have been traditionally identified as transcription factors. In the presence of ligand, ARs reside in the nucleus, where, upon ligand binding, the receptors dimerize and bind to specific response elements in the promoter region of hormone-responsive genes. However, in this report, we describe the discovery that ARs are also present in axons and dendrites within the mammalian central nervous system. AR expression in axons was identified in the rat brain at the light microscopic level using two different antibodies directed against the N terminus of the AR protein and nickel intensified 3′-3′-diaminobenzidine, and also using fluorescence methods and confocal microscopy. This distribution was confirmed at the ultrastructural level. In addition, AR immunoreactivity was identified in small dendrites at the ultrastructural level. AR-immunoreactive axons were observed primarily in the cerebral cortex and were rare in regions where nuclear AR expression is abundant. The observation that ARs are present in axons and dendrites highlights the possibility that androgens play an important and novel extranuclear role in neuronal function.Peer Reviewe

Adsorption of representative pharmaceutical compounds from hospital wastewater by carbon materials

Pharmaceuticals are a class of emerging environmental contaminants that are extensively and increasingly being used in human and veterinary medicine. The worldwide consumption of these substances has increased in both hospitals and households, which represents a major concern in terms of their potential harmful effects on the environment and human health [1]. Thus, fluoroquinolone antibiotics are widely used in human medicine and animal breeding for preventing and curing diseases. Ciprofloxacin is a wide-spectrum fluoroquinolone antibiotic extensively used in the world, which can generate high contributions to public sewers. Meanwhile, carbamazepine, one of the most widely prescribed psychoactive drugs, shows important endocrine disrupting effects and it is frequently detected in high concentrations in both WWTPs effluents and river water. Because of the removal efficiency of these compounds in the conventional wastewater treatment plants is not complete (ranging from 7-8% for carbamazepine), it is necessary the implementation of tertiary technologies in order to achieve WWTPs effluents with a better quality. Adsorption onto carbon materials has proven as an efficient treatment in the removal of a broad spectrum of micro-pollutants. This work has been focused on the study of equilibrium adsorption of carbamazepine (CBZ) and ciprofloxacin (CPX) from ultrapure water at 30 ºC using carbonaceous materials. Commercial carbon materials (AC-F400 activated carbon, multi-walled carbon nanotubes, MWNT, and carbon nanofibers, CNF) and lab-synthesized activated carbons from peach stones (AC-PS) and rice husk (AC-RH) as precursors have been used. Moreover, carbon adsorbents have been used to treat a real hospital wastewater containing 55 different pharmaceutical compounds. Among them, both CBZ and CPX were found at concentrations of 162.55 and \u3e 40 ng.L-1, respectively. The removal efficiency of quality macroscopic parameters (Total Organic Carbon concentration, TOC, Total Nitrogen concentration, TN, carbonates, CO32-, and aromaticity) and each of the pharmaceuticals contained in the wastewater was evaluated. Large adsorption capacities of CBZ and CPX (around 240 and 200 mg.g-1) were found in 4 hours, using adsorbent doses ranging from 2-3 g.L-1, natural pH, temperature of 30 ºC and stirring rate of 250 rpm. In addition, competitive adsorption experiments using both pollutants in ultrapure water have been performed. The bi-component adsorption systems were reasonably well-fitted by the extended Freundlich model equation. In the treatment of the hospital wastewater, a maximum TOC reduction of 96.5% ([TOC]0 = 110 mg L-1) was achieved by adsorption onto AC-RH activated carbon, since all the studied macroscopic parameters were too efficiently removed. Moreover, by the adsorption treatment, the complete disappearance of all the pharmaceutical compounds (except two of them) was observed. References [1] S. Ortiz de García, G. Pinto Pinto, P. García Encina, R. Irusta Mata, Consumption and occurrence of pharmaceutical and personal care products in the aquatic environment in Spain, Sci. Total Environ. 444 (2013) 451–465

Cómo poner puertas al campo : tres revisiones panorámicas sobre el uso de biomarcadores en prevención personalizada de enfermedades crónicas

Se incluye PDF de la presentación y vídeo del seminario.El seminario trata de dar respuesta a qué biomarcadores hay disponibles o en desarrollo para la prevención personalizada de enfermedades crónicas en la población general. Las revisiones realizadas resumen las principales características y conclusiones de la bibliografía sobre este tema. Abarca los tres principales grupos de enfermedades crónicas:11 tipos de cáncer, 9 enfermedades cardiovasculares y 7 enfermedades neurodegenerativas.N

Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic

This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic

Glial expression of estrogen and androgen receptors after rat brain injury

Estrogens and androgens can protect neurons from death caused by injury to the central nervous system. Astrocytes and microglia are major players in events triggered by neural lesions. To determine whether glia are direct targets of estrogens or androgens after neural insults, steroid receptor expression in glial cells was assessed in two different lesion models. An excitotoxic injury to the hippocampus or a stab wound to the parietal cortex and hippocampus was performed in male rats, and the resultant expression of steroid receptors in glial cells was assessed using double-label immunohistochemistry. Both lesions induced the expression of estrogen receptors (ERs) and androgen receptors (ARs) in glial cells. ERα was expressed in astrocytes immunoreactive (ERα-ir) for glial fibrillary acidic protein or vimentin. AR immunoreactivity colocalized with microglial markers, such as Griffonia simplicifolia lectin-1 or OX-6. The time course of ER and AR expression in glia was studied in the stab wound model. ERα-ir astrocytes and AR-ir microglia were observed 3 days after lesion. The number of ERα-ir and AR-ir glial cells reached a maximum 7 days after lesion and returned to low levels by 28 days postinjury. The studies of ERβ expression in glia were inconclusive; different results were obtained with different antibodies. In sum, these results suggest that reactive astrocytes and reactive microglia are a direct target for estrogens and androgens, respectively. © 2002 Wiley-Liss, Inc.Peer Reviewe

Astroglia play a key role in the neuroprotective actions of estrogen

Peer Reviewe

Space flight affects magnocellular supraoptic neurons of young prepuberal rats: Transient and permanent effects

Effects of microgravity on postural control and volume of extracellular fluids as well as stress associated with space flight may affect the function of hypothalamic neurosecretory neurons. Since environmental modifications in young animals may result in permanent alterations in neuroendocrine function, the present study was designed to determine the effect of a space flight on oxytocinergic and vasopressinergic magnocellular hypothalamic neurons of prepuberal rats. Fifteen-day-old Sprague-Dawley female rats were flown aboard the Space Shuttle Columbia (STS-90, Neurolab mission, experiment 150) for 16 days. Age-matched litters remained on the ground in cages similar to those of the flight animals. Six animals from each group were killed on the day of landing and eight animals from each group were maintained under standard vivarium conditions and killed 18 weeks after landing. Several signs of enhanced transcriptional and biosynthetic activity were observed in magnocellular supraoptic neurons of flight animals on the day of landing compared to control animals. These include increased c-Fos expression, larger nucleoli and cytoplasm, and higher volume occupied in the neuronal perikaryon by mitochondriae, endoplasmic reticulum, Golgi apparatus, lysosomes and cytoplasmic inclusions known as nematosomes. In contrast, the volume occupied by neurosecretory vesicles in the supraoptic neuronal perikarya was significantly decreased in flight rats. This decrease was associated with a significant decrease in oxytocin and vasopressin immunoreactive levels, suggestive of an increased hormonal release. Vasopressin levels, cytoplasmic volume and c-Fos expression returned to control levels by 18 weeks after landing. These reversible effects were probably associated to osmotic stimuli resulting from modifications in the volume and distribution of extracellular fluids and plasma during flight and landing. However, oxytocin levels were still reduced at 18 weeks after landing in flight animals compared to controls. This indicates that space flight during prepuberal age may induce irreversible modifications in the regulation of oxytocinergic neurons, which in turn may result in permanent endocrine and behavioral impairments. © 2001 Elsevier Science B.V. All rights reserved.Peer Reviewe

Seletividade de herbicidas para a cultura de milho (Zea mays) aplicados em diferentes estádios fenológicos da cultura Selectivity to corn crop (Zea mays) of herbicides applied in different crop phenological stages

O objetivo deste trabalho foi avaliar a seletividade de herbicidas aplicados em condições de pré e pós-emergência da cultura de milho, conduzida sob sistema de semeadura direta, sem a presença de plantas daninhas durante todo o ciclo da cultura. O híbrido utilizado foi o Pioneer 3027, e o delineamento experimental adotado foi em blocos casualizados, com 22 tratamentos e três repetições. Os tratamentos herbicidas utilizados (em g i.a. ha-1), com os respectivos estádios fenológicos (número de folhas definitivas = NF) no momento da aplicação dos respectivos tratamentos herbicidas, foram: atrazine + metolachlor (1.400 + 2.100) em condições de pré-emergência da cultura; (atrazine + metolachlor) + nicosulfuron [(1.000 + 1.500 + 20)] com a cultura apresentando NF = 2; atrazine + óleo vegetal (2.400 + 1.800), NF = 2, 4 e 8; atrazine + simazine (1.250 + 1.250), NF = 2, 4 e 8; nicosulfuron (40 - NF = 2, 4 e 8; 20 - NF = 4 e 8 e 52 - NF = 4 e 8); e (atrazine + óleo vegetal) + nicosulfuron [(800 + 600) + 20; (800 + 600) + 40 e (800 + 600) + 52), NF = 4 e 8]. Foram feitas avaliações visuais de sintomas de fitotoxicidade provocados pelos herbicidas aos 7, 14 e 21 dias após aplicação, usando a escala proposta pela European Weed Research Council, além dos parâmetros relativos aos componentes de produção da cultura e produtividade final. Os resultados obtidos indicaram que a duração dos estádios fenológicos da cultura não foi afetada pelos herbicidas utilizados e que alguns tratamentos herbicidas, quando aplicados no estádio fenológico 2 (NF = 8 ), reduzem o rendimento da cultura, devido à alteração do número de fileiras por espiga, do número de grãos por fileira e da massa de 1.000 grãos de milho, sendo recomendável a aplicação de herbicidas na cultura de milho até o estádio fenológico 1 (NF = 4), para evitar danos à cultura por fitotoxicidade.<br>The objective of this research was to evaluate the selectivity of pre and post-emergence herbicides on corn crop under no-tillage system, kept weed-free throughout the crop cycle. The corn hybrid Pioneer 3027 was sown and the experimental design consisted of randomized blocks with 22 treatments and 3 replications. The following herbicide treatments (in g a.i. ha-1) were applied in the respective phenological stages (number of definitive leaves = NF): atrazine + metolachlor (1,400 + 2,100) under pre-emergence conditions of the crop; (atrazine + metolachlor) + nicosulfuron [(1,000 + 1,500) + 20] with the crop presenting NF = 2; atrazine + vegetal oil (2,400 + 1,800), NF = 2, 4 and 8, atrazine + simazine (1,250 + 1,250), NF = 2, 4 and 8; nicosulfuron (40 - NF = 2, 4 and 8; 20 _ NF = 4 and 8 and 52 _ NF = 4 and 8); (atrazine + vegetal oil) + nicosulfuron [(800 + 600) + 20; (800 + 600) + 40 e (800 + 600) + 52), NF = 4 and 8. Visual evaluations of the phytotoxicity symptoms were performed at 7, 14, and 21 days after each herbicide application, adopting the European Weed Research Council grading, besides parameters related to crop yield components and final yield. The results indicated that the herbicides did not affect the duration of the phenological stage of the crop. When sprayed at the phenological stage 2 (NF = 8), some herbicides reduced crop yield due to the decrease in total number of corn grain rows per ear, total number of grains per row, and mass of 1,000 grains; being thus advisable to apply herbicides in the corn crop from seeding through the phenological stage 1 (NF = 4), in order to avoid phytotoxicity to the corn crop

Classical androgen receptors in non-classical sites in the brain

Androgen receptors are expressed in many different neuronal populations in the central nervous system where they often act as transcription factors in the cell nucleus. However, recent studies have detected androgen receptor immunoreactivity in neuronal and glial processes of the adult rat neocortex, hippocampal formation, and amygdala as well as in the telencephalon of eastern fence and green anole lizards. This review discusses previously published findings on extranuclear androgen receptors, as well as new experimental results that begin to establish a possible functional role for androgen receptors in axons within cortical regions. Electron microscopic studies have revealed that androgen receptor immunoreactive processes in the rat brain correspond to axons, dendrites and glial processes. New results show that lesions of the dorsal CA1 region by local administration of ibotenic acid reduce the density of androgen receptor immunoreactive axons in the cerebral cortex and the amygdala, suggesting that these axons may originate in the hippocampus. Androgen receptor immunoreactivity in axons is also decreased by the intracerebroventricular administration of colchicine, suggesting that androgen receptor protein is transported from the perikaryon to the axons by fast axonal transport. Androgen receptors in axons located in the cerebral cortex and amygdala and originating in the hippocampus may play an important role in the rapid behavioral effects of androgens. © 2008 Elsevier Inc. All rights reserved.Peer Reviewe

Testosterone decreases reactive astroglia and reactive microglia after brain injury in male rats: Role of its metabolites, oestradiol and dihydrotestosterone

Previous studies have shown that the neuroprotective hormone, testosterone, administered immediately after neural injury, reduces reactive astrogliosis. In this study we have assessed the effect of early and late therapy with testosterone or its metabolites, oestradiol and dihydrotestosterone, on reactive astroglia and reactive microglia after a stab wound brain injury in orchidectomized Wistar rats. Animals received daily s.c. injections of testosterone, oestradiol or dihydrotestosterone on days 0-2 or on days 5-7 after injury. The number of vimentin immunoreactive astrocytes and the volume fraction of major histocompatibility complex-II (MHC-II) immunoreactive microglia were estimated in the hippocampus in the lateral border of the wound. Both early and delayed administration of testosterone or oestradiol, but not dihydrotestosterone, resulted in a significant decrease in the number of vimentin-immunoreactive astrocytes. The volume fraction of MHC-II immunoreactive microglia was significantly decreased in the animals that received testosterone or oestradiol in both early and delayed treatments and in animals that received early dihydrotestosterone administration. Thus, both early and delayed administration of testosterone reduces reactive astroglia and reactive microglia and these effects may be at least in part mediated by oestradiol, while dihydrotestosterone may mediate part of the early effects of testosterone on reactive microglia. In conclusion, testosterone controls reactive gliosis and its metabolites, oestradiol and dihydrotestosterone, may be involved in this hormonal effect. The regulation of gliosis may be part of the neuroprotective mechanism of testosterone. © The Authors (2007).Peer Reviewe