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1.
Eur J Neurosci ; 36(8): 3096-102, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22831399

RESUMEN

Previous studies showed that the mineralocorticoid receptor (MR) is needed for behavioral flexibility in a fear conditioning paradigm. Female mice with forebrain-specific deletion of the MR gene (MR(CaMKCre) ) were unable to show extinction of contextual fear, and could not discriminate between cue and context fear unlike control mice. In the present study, male and female (MR(CaMKCre) ) mice and control littermates were used to study sex-specific fear conditioning, memory performance and extinction. The fear conditioning paradigm assessed both context- and cue-related fear within one experimental procedure. We observed that at the end of the conditioning all mice acquired the fear-motivated response. During the first minutes of the memory test, both male and female MR(CaMKCre) mice remembered and feared the context more than the control mice. Furthermore, female MR(CaMKCre) mice were not able to extinguish this memory even on the second day of memory testing. The female mutants also could not discriminate between cue (more freezing) and context periods (less freezing). In contrast, male MR(CaMKCre) mice and the controls showed extinction and were capable to discriminate, although the MR(CaMKCre) mice needed more time before they started extinction. These findings further support the relevance of MR for behavioral flexibility and extinction of fear-motivated behavior. In conclusion, the loss of MR in the forebrain results in large differences in emotional and cognitive behaviors between female and male mice, which suggests a role of this receptor in the female prevalence of stress- and anxiety-regulated disorders.


Asunto(s)
Miedo/fisiología , Memoria/fisiología , Prosencéfalo/fisiología , Receptores de Mineralocorticoides/fisiología , Caracteres Sexuales , Animales , Señales (Psicología) , Extinción Psicológica , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Prosencéfalo/metabolismo , Receptores de Mineralocorticoides/genética
2.
Neurobiol Learn Mem ; 98(1): 33-40, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22543192

RESUMEN

Corticosteroid effects on cognitive abilities during behavioral adaptation to stress are mediated by two types of receptors. While the glucocorticoid receptor (GR) is mainly involved in the consolidation of memory, the mineralocorticoid receptor (MR) mediates appraisal and initial responses to novelty. Recent findings in humans and mice suggest that under stress, the MR might be involved in the use of different learning strategies. Here, we used male mice lacking the MR in the forebrain (MR(CaMKCre)), which were subjected to 5-10 min acute restraint stress, followed 30 min later by training trials on the circular hole board. Mice had to locate an exit hole using extra- and intra-maze cues. We assessed performance and the use of spatial and stimulus-response strategies. Non-stressed MR(CaMKCre) mice showed delayed learning as compared to control littermates. Prior stress impaired performance in controls, but did not further deteriorate learning in MR(CaMKCre) mice. When stressed, 20-30% of both MR(CaMKCre) and control mice switched from a spatial to a stimulus-response strategy, which rescued performance in MR(CaMKCre) mice. Furthermore, MR(CaMKCre) mice showed increased GR mRNA expression in all CA areas of the hippocampus and an altered basal and stress-induced corticosterone secretion, which supports their role in the modulation of neuroendocrine activity. In conclusion, our data provide evidence for the critical role of MR in the fast formation of spatial memory. In the absence of forebrain MR spatial learning performance was under basal circumstances impaired, while after stress further deterioration of performance was rescued by switching behavior increasingly to a stimulus-response strategy.


Asunto(s)
Adaptación Psicológica/fisiología , Aprendizaje por Laberinto/fisiología , Prosencéfalo/metabolismo , Receptores de Mineralocorticoides/metabolismo , Estrés Fisiológico/fisiología , Estrés Psicológico/metabolismo , Animales , Corticosterona/sangre , Señales (Psicología) , Hipocampo/metabolismo , Masculino , Memoria/fisiología , Ratones , Ratones Transgénicos , Receptores de Mineralocorticoides/genética , Estrés Psicológico/genética
3.
Transl Med UniSa ; 19: 103-108, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31360674

RESUMEN

The European Commission (DG SANTE) launched a call for proposals in November 2017 on strategic initiatives for a Joint Statement in 2018. Ten proposals were voted until December 7th in the European Union Health Policy Platform[1]; the proposal under the theme Smart Healthy Age-Friendly Environments (SHAFE)[2] was the most voted and was confirmed by the European Commission in March 2018. In this context, since March 2018, Cáritas Coimbra and AFEdemy Ltd are thus coordinating one of the three Thematic Networks for 2018, SHAFE, in close cooperation with main partners, such as the European Innovation Partnership on Active and Healthy Ageing (EIP-AHA), the European Innovation Partnership on Smart Cities and Communities (EIP-SCC), the Reference Sites Collaborative Network, the European Covenant on Demographic Change, Eurocities, the European Health Telematics Association (EHTEL), the European Connected Health Alliance (ECHAlliance), the European Construction, Built Environment and Energy Efficient Building Technology Platform (ECTP) and the European Centre for Social Welfare Policy and Research. SHAFE aims to facilitate the creation of healthy and friendly environments for all ages through the use of new technologies, towards the production of a comprehensive and participatory Joint Statement. This document was presented to the European Commission on 12 November 2018, with five main areas of recommendations to the EC, Member States and other local, regional and national organisations and is open for endorsement and implementation from this date onwards.

4.
Endocrinology ; 149(12): 6366-77, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18635659

RESUMEN

In CD1 mice we investigated the hypothalamic-pituitary-adrenal (HPA) axis response to maternal separation for 8 h daily from postnatal d 3 to 5. At d 3 a slow separation-induced corticosterone response developed that peaked after 8 h, and the pups became responsive to stressors. On the second and third day, the response to 8 h separation rapidly attenuated, whereas the response to novelty did not, a pattern reflected by the hypothalamic c-fos mRNA response. If maternal separation and exposure to novelty were combined, then after the third such daily exposure, the sensitivity to the stressor was further enhanced. Meanwhile, basal corticosterone and ACTH levels were persistently suppressed 16 h after pups were reunited with their mothers. To explain the HPA axis desensitization after repeated separation, we found that circulating ghrelin levels increased and glucose levels decreased after all periods of maternal separation, ruling out a role of altered metabolism. Glucocorticoid feedback was not involved either because a glucocorticoid receptor antagonist amplified the corticosterone response after the first but became ineffective after the third separation. In contrast, a mineralocorticoid receptor antagonist decreased and increased corticosterone levels after the first and third period of separation, respectively. In conclusion, the newborn's HPA axis readily desensitizes to repeated daily maternal separation, but continues to respond to novelty in a manner influenced by a central mineralocorticoid receptor- rather than glucocorticoid receptor-mediated mechanism.


Asunto(s)
Conducta Exploratoria/fisiología , Sistema Hipotálamo-Hipofisario/fisiología , Privación Materna , Sistema Hipófiso-Suprarrenal/fisiología , Hormona Adrenocorticotrópica/sangre , Animales , Animales Recién Nacidos , Peso Corporal/fisiología , Corticosterona/sangre , Hormona Liberadora de Corticotropina/genética , Femenino , Ghrelina/genética , Sistema Hipotálamo-Hipofisario/metabolismo , Hibridación in Situ , Ratones , Sistema Hipófiso-Suprarrenal/metabolismo , Proteínas Proto-Oncogénicas c-fos/genética , Receptores de Glucocorticoides/genética , Receptores de Mineralocorticoides/genética , Estrés Psicológico/fisiopatología
5.
Leukemia ; 30(2): 310-7, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26286115

RESUMEN

This nationwide population-based study assessed trends in treatment, trial participation and survival among 1833 adult patients diagnosed with acute lymphoblastic leukemia (ALL) in the Netherlands between 1989 and 2012 reported to the Netherlands Cancer Registry. Patients were categorized into four periods and five age groups (18-24, 25-39, 40-59, 60-69 and ⩾70 years). The application of allogeneic stem cell transplantation (alloSCT), particularly reduced-intensity conditioning (RIC) alloSCT, increased over time up to age 70 years. The inclusion rate in the trials was 67, 66, 55, 58 and 0% for the five age groups. Survival improved over time for patients below 70 years. Five-year relative survival in the period 2007-2012 was 75, 57, 37, 22 and 5% for the five age groups. In that same period, 5-year overall survival among patients aged 18-39 years was 68% for the chemotherapy-alone group and 66% for the alloSCT group. For patients aged 40-69 years, the corresponding estimates were 24 and 41%. Pronounced survival improvement observed among patients aged 18-39 years might mainly be explained by implementation of pediatric-based regimens since 2005, whereas among patients aged 40-69 years, increased application of RIC-alloSCT has contributed significantly to the observed improvement. Outcome of patients aged ⩾70 remains unsatisfactory, indicating a need for specific trials for the elderly.


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adolescente , Adulto , Anciano , Femenino , Trasplante de Células Madre Hematopoyéticas , Humanos , Masculino , Persona de Mediana Edad , Participación del Paciente , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad
6.
Endocrinology ; 146(3): 1458-64, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15591147

RESUMEN

During postnatal development, mice undergo a period of reduced responsiveness of the pituitary-adrenal axis, the stress hyporesponsive period (SHRP), which is largely under control of maternal signals. The present study was designed to test the hypothesis that this quiescence in hypothalamic-pituitary-adrenal (HPA) activity is mediated by glucocorticoid feedback. For this purpose, the role of mineralocorticoid receptors (MR) and glucocorticoid receptors (GR) in control of HPA activity was examined during the SHRP and in response to 24 h of maternal deprivation. Nondeprived or deprived (24 h) CD1 mice on postnatal d 8 were injected sc at 16 and 8 h before testing with the MR antagonist RU28318 or the GR antagonist RU38486. The results showed that, in nondeprived mice, blockade of GR rather than MR triggered a profound increase in anterior pituitary proopiomelanocortin mRNA, circulating ACTH, and corticosterone concentrations. In contrast, CRH mRNA in hypothalamus and GR mRNA in hippocampus and hypothalamus were decreased. Blockade of the GR during the deprivation period amplified the rise in corticosterone induced by maternal deprivation, whereas it reversed the deprivation effect on the other HPA markers, leading to profound increases in plasma ACTH, proopiomelanocortin mRNA expression in the anterior pituitary, CRH mRNA expression in the paraventricular nucleus, and MR mRNA expression in the hippocampus, but not in GR mRNA expression in the hippocampus and paraventricular nucleus. In conclusion, the data suggest that control of postnatal pituitary-adrenal activity during the SHRP involves GR-mediated feedback in the anterior pituitary, which is further potentiated in the absence of the mother.


Asunto(s)
Glándulas Suprarrenales/metabolismo , Adenohipófisis/metabolismo , Receptores de Glucocorticoides/antagonistas & inhibidores , Receptores de Glucocorticoides/fisiología , Espironolactona/análogos & derivados , Hormona Adrenocorticotrópica/sangre , Animales , Animales Recién Nacidos , Corticosterona/metabolismo , Hipocampo/metabolismo , Hipotálamo/metabolismo , Hibridación in Situ , Ratones , Antagonistas de Receptores de Mineralocorticoides/farmacología , Proopiomelanocortina/metabolismo , ARN Mensajero/metabolismo , Espironolactona/farmacología , Temperatura , Factores de Tiempo
7.
Int J Dev Neurosci ; 21(3): 125-32, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12711350

RESUMEN

The main characteristic of the postnatal development of the stress system in the rat is the so-called stress hypo-responsive period (SHRP). Lasting from postnatal day (pnd) 4 to pnd 14, this period is characterized by very low basal corticosterone levels and an inability of mild stressors to induce an enhanced ACTH and corticosterone release. During the last years, the mouse has become a generally used animal in stress research, also due to the wide availability of genetically modified mouse strains. However, very few data are available on the ontogeny of the stress system in the mouse. This study therefore describes the postnatal ontogeny of peripheral and central aspects of the hypothalamic-pituitary-adrenal (HPA) axis in the mouse. We measured ACTH and corticosterone in blood and CRH, urocortin 3 (UCN3), mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) transcripts in the brain at postnatal days 1, 2, 4, 6, 9, 12, 14 and 16. Our results show that we can subdivide the postnatal development of the HPA axis in the mouse in two phases. The first phase corresponds to the SHRP in the rat and lasts from right after birth (pnd 1) until pnd 12. Basal corticosterone levels were low and novelty exposure did not enhance corticosterone or ACTH levels. This period is further characterized by a high expression of CRH in the paraventricular nucleus (PVN) of the hypothalamus. Expression levels of GR in the hippocampus and UCN3 in the perifornical area are low at birth but increase significantly during the SHRP, both reaching the highest expression level at pnd 12. In the second phase, the mice have developed past the SHRP and were now exhibiting enhanced corticosterone basal levels and a response of ACTH and corticosterone to mild novelty stress. CRH expression was decreased significantly, while expression of UCN3 and GR remained high, with a small decrease at pnd 16. The expression of MR in the hippocampus was very dynamic throughout the postnatal development of the HPA axis and changed in a time and subregion specific manner. These results demonstrate for the first time the correlation between the postnatal endocrine development of the mouse and gene expression changes of central regulators of HPA axis function.


Asunto(s)
Sistema Hipotálamo-Hipofisario/crecimiento & desarrollo , Sistema Hipófiso-Suprarrenal/crecimiento & desarrollo , Estrés Psicológico/fisiopatología , Hormona Adrenocorticotrópica/sangre , Envejecimiento/metabolismo , Animales , Encéfalo/fisiopatología , Corticosterona/sangre , Hormona Liberadora de Corticotropina/metabolismo , Femenino , Sistema Hipotálamo-Hipofisario/patología , Masculino , Privación Materna , Ratones , Fosfoproteínas/metabolismo , Sistema Hipófiso-Suprarrenal/patología , ARN Mensajero/metabolismo , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/metabolismo , Valores de Referencia , Estrés Psicológico/sangre , Estrés Psicológico/patología , Urocortinas
8.
Int J Dev Neurosci ; 28(2): 217-24, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19897026

RESUMEN

One of the striking characteristics of the developing neuroendocrine system of rats and mice is the stress hypo-responsive period (SHRP), i.e. low basal corticosterone secretion and the inability to increase corticosterone in response to mild stressors during the first 2 weeks of life. However, immediately after 24 h of deprivation from maternal care the response of the hypothalamic-pituitary-adrenal (HPA) axis to mild stressors is enhanced. This study examines in CD1 mouse pups the recovery pattern of markers of HPA axis (re)activity from maternal deprivation (once for 24 h from postnatal days (pnds) 3 to 4). As expected, deprivation induced a profound corticosterone response to novelty immediately after deprivation. In contrast, 1 day after reunion with the mother (pnd 5), this effect was abolished, lasting for at least 3 days. Basal corticosterone remained even below control levels. Corticotropin-releasing hormone (CRH) mRNA expression in the hypothalamic paraventricular nucleus (PVN) was suppressed for 2 days, exceeded control levels at pnds 7 and 8, and subsequently followed the gradual decline observed in controls until pnd 12. Delayed and rather short-lasting changes were found for adrenocorticotropic hormone (low at pnd 5), and glucocorticoid receptor mRNA expression (decreased in the PVN at pnd 4, and in the hippocampal CA1 area at pnd 5). Hippocampal mineralocorticoid receptor mRNA expression was unaffected. From pnds 9 to 13, both deprived and control pups gradually emerged from the SHRP in a similar temporal pattern. In conclusion, maternal deprivation at pnd 3 augments hypo-responsiveness of corticosterone secretion to mild stress for several days, but does not affect the duration of the SHRP. Whether CRH and glucocorticoid receptor changes are cause or consequence remains to be established.


Asunto(s)
Ansiedad de Separación/fisiopatología , Corticosterona/metabolismo , Sistema Hipotálamo-Hipofisario/fisiopatología , Madres , Sistema Hipófiso-Suprarrenal/fisiopatología , Animales , Animales Recién Nacidos , Ratones , Sistema Hipófiso-Suprarrenal/efectos de los fármacos
9.
Appl Opt ; 36(1): 180-213, 1997 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18250660

RESUMEN

The recent developments in light generation and detection techniques have opened new possibilities for optical medical imaging, tomography, and diagnosis at tissue penetration depths of ~10 cm. However, because light scattering and diffusion in biological tissue are rather strong, the reconstruction of object images from optical projections needs special attention. We describe a simple reconstruction method for diffuse optical imaging, based on a modified backprojection approach for medical tomography. Specifically, we have modified the standard backprojection method commonly used in x-ray tomographic imaging to include the effects of both the diffusion and the scattering of light and the associated nonlinearities in projection image formation. These modifications are based primarily on the deconvolution of the broadened image by a spatially variant point-spread function that is dependent on the scattering of light in tissue. The spatial dependence of the deconvolution and nonlinearity corrections for the curved propagating ray paths in heterogeneous tissue are handled semiempirically by coordinate transformations. We have applied this method to both theoretical and experimental projections taken by parallel- and fan-beam tomography geometries. The experimental objects were biomedical phantoms with multiple objects, including in vitro animal tissue. The overall results presented demonstrate that image-resolution improvements by nearly an order of magnitude can be obtained. We believe that the tomographic method presented here can provide a basis for rapid, real-time medical monitoring by the use of optical projections. It is expected that such optical tomography techniques can be combined with the optical tissue diagnosis methods based on spectroscopic molecular signatures to result in a versatile optical diagnosis and imaging technology.

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