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Dive into the research topics where Fernando Chacón is active.

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Featured researches published by Fernando Chacón.


Chronobiology International | 2005

24‐Hour Changes in ACTH, Corticosterone, Growth Hormone, and Leptin Levels in Young Male Rats Subjected to Calorie Restriction

Fernando Chacón; Ana I. Esquifino; Mario Perello; Daniel P. Cardinali; Eduardo Spinedi; María P. Alvarez

Calorie restriction of young male rats increases plasma prolactin, decreases luteinizing hormone (LH) and testosterone, and disrupts their 24 h secretory pattern. To study whether this could be the consequence of stress, we examined the 24 h variations of plasma adrenocorticotropic hormone (ACTH) corticosterone, growth hormone (GH), leptin, and adrenal corticosterone. Rats were submitted to a calorie restriction equivalent to a 66% of usual intake for 4 weeks, starting on day 35 of life. Controls were kept in individual cages and allowed to eat a normal calorie regimen. Significantly lower ACTH levels were detected in calorie‐restricted rats. Plasma corticosterone levels during the light phase of the daily cycle were significantly higher in calorie‐restricted rats. Time‐of‐day variation in plasma ACTH and corticosterone levels attained significance in calorie‐restricted rats only, with a maximum toward the end of the resting phase. The daily pattern of adrenal gland corticosterone mirrored that of circulating corticosterone; however, calorie restriction reduced its levels. Plasma ACTH and corticosterone correlated significantly in controls only. Calorie restriction decreased plasma GH and leptin, and it distorted 24 h rhythmicity. In a second study, plasma ACTH and corticosterone levels were measured in group‐caged rats, isolated control rats, and calorie‐restricted rats during the light phase of the daily cycle. Plasma ACTH of calorie‐restricted rats was lower, and plasma corticosterone was higher, compared with isolated or group‐caged controls. The changes in the secretory pattern of hormones hereby reported may be part of the neuroendocrine and metabolic mechanisms evolved to maximize survival during periods of food shortage.


Journal of Circadian Rhythms | 2004

24-hour changes in circulating prolactin, follicle-stimulating hormone, luteinizing hormone and testosterone in male rats subjected to social isolation

Ana I. Esquifino; Fernando Chacón; Carlos F. Reyes Toso; Daniel P. Cardinali

Background This work analyzes the effect of social isolation (a mild stressor) on the 24-h variation of pituitary-testicular function in young Wistar rats, assessed by measuring circulating levels of prolactin, FSH, LH and testosterone. Methods Animals were either individually caged or kept in groups (4–5 animals per cage) under a 12:12 h light-dark cycle (lights on at 0800 h) for 30 days starting on day 35 of life. Rats were killed at 4-h intervals during a 24-h cycle, beginning at 0900 h. Results Isolation brought about a decrease in prolactin, LH and testosterone secretion and an increase of FSH secretion. In isolated rats the 24-h secretory pattern of prolactin and testosterone became modified, i.e., the maximum in prolactin seen in control animals at the beginning of the activity span was no longer detected, whereas the maximum in circulating testosterone taking place at 1700 h in controls was phase-delayed to 2100 h in isolated rats. Conclusion Social isolation affects the 24-h variation of pituitary-testicular function in young rats. Secretion of prolactin, LH and testosterone decreases, and secretion of FSH increases, in isolated rats. The maximum in prolactin seen in group-caged rats at the beginning of the activity span is not observed in isolated rats. The maximum in circulating testosterone taking place at the second part of the rest span in controls is phase-delayed to the light-dark transition in isolated rats.


Chronobiology International | 2004

24-Hour changes in circulating prolactin, follicle-stimulating hormone, luteinizing hormone, and testosterone in young male rats subjected to calorie restriction

Fernando Chacón; Pilar Cano; Daniel P. Cardinali; Ascensión Marcos; Ana I. Esquifino

This work analyzes the effect of calorie restriction on the 24 h variation of pituitary-testicular function in young male Wistar rats by measuring the circulating levels of prolactin, follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone. Control animals were provided an equilibrium calorie diet and the experimental animals a calorie-restriction diet equivalent to 66% of food restriction for four weeks starting on day 35 of life. Different groups of control and experimental rats were killed at 6 h intervals around the clock, beginning 1 h after light on (HALO). Compared to the control animals, the mean secretion of prolactin was augmented and that of LH and testosterone decreased in calorie-restricted rats, whereas FSH release remained unchanged. Significant changes in the 24 h secretory pattern of circulating prolactin, LH, and testosterone occurred in the calorie-restricted rats. These include the appearance of a second maximum of plasma prolactin at 21 HALO, blunting of the LH peak seen at 13 HALO, and phase-shift of the testosterone peak from 13 HALO in controls to 17 HALO in calorie-restricted rats. The significant positive correlation between individual LH and testosterone levels found in controls was no longer observed in calorie-restricted rats. Availability of nutrients presumably affects the mechanisms that modulate the circadian variation of the pituitary-gonadal axis in growing male rats.


BMC Physiology | 2001

Age-dependent changes in 24-hour rhythms of catecholamine content and turnover in hypothalamus, corpus striatum and pituitary gland of rats injected with Freund's adjuvant

Pilar Cano; Daniel P. Cardinali; Fernando Chacón; Patricia O. Castrillón; Carlos A. Reyes Toso; Ana I. Esquifino

BackgroundLittle information is available on the circadian sequela of an immune challenge in the brain of aged rats. To assess them, we studied 24-hour rhythms in hypothalamic and striatal norepinephrine (NE) content, hypothalamic and striatal dopamine (DA) turnover and hypophysial NE and DA content, in young (2 months) and aged (18–20 months) rats killed at 6 different time intervals, on day 18th after Freunds adjuvant or adjuvants vehicle administration.ResultsAging decreased anterior and medial hypothalamic NE content, medial and posterior hypothalamic DA turnover, and striatal NE concentration and DA turnover. Aging also decreased NE and DA content in pituitary neurointermediate lobe and augmented DA content in the anterior pituitary lobe. Immunization by Freunds adjuvant injection caused: (i) reduction of DA turnover in anterior hypothalamus and corpus striatum; (ii) acrophase delay of medial hypothalamic DA turnover in old rats, and of striatal NE content in young rats; (iii) abolition of 24-h rhythm in NE and DA content of neurointermediate pituitary lobe, and in DA content of anterior lobe, of old rats.ConclusionsThe decline in catecholamine neurotransmission with aging could contribute to the decrease of gonadotropin and increase of prolactin release reported in similar groups of rats. Some circadian responses to immunization, e.g. suppression of 24-h rhythms of neurointermediate lobe NE and DA and of anterior lobe DA were seen only in aged rats.


Endocrine | 2004

24-hour pattern of circulating prolactin and growth hormone levels and submaxillary lymph node immune responses in growing male rats subjected to social isolation.

Ana I. Esquifino; María P. Alvarez; Pilar Cano; Fernando Chacón; Carlos F. Reyes Toso; Daniel P. Cardinali

To assess the effect of social isolation of growing rats on 24-h rhythmicity of circulating prolactin and growth hormone (GH) levels and submaxillary lymph node immune responses, male Wistar rats were either individually caged or kept in groups (4–5 animals per cage) for 30 d starting on d 35 of life. Plasma prolactin and GH levels, and submaxillary lymph node lymphocyte subset populations, interferon (IFN)-γ release and mitogenic responses to concanavalin A (Con A) and lipopolysaccharide (LPS) were determined at six time intervals during the 24 h span. Social isolation brought about changes in mean values and 24-h pattern of plasma prolactin and GH levels and lymph node immune responses. After isolation, prolactin and GH mean values decreased, and lymph node T, B, non T-non B, CD8+, and CD4+-CD8+ cells augmented, whereas lymph node CD4+/CD8+ ratio, IFN-γ release and mitogenic responses decreased. Social isolation resulted in disruption of 24 h rhythmicity of every immune parameter tested. CD4+/CD8+ ratio, IFN-γ release and Concanavalin A (Con A) and lipopolysaccharide (LPS) responses correlated significantly with plasma prolactin or GH levels while T/B ratio correlated with plasma prolactin levels only. B, non T-non B, and CD4+-CD8+ cells correlated negatively with plasma prolactin. Modifications in mean value and 24-h rhythmicity of plasma prolactin and GH levels are presumably involved in the effect of social isolation on immune responsiveness.


JMIR Research Protocols | 2016

Transdiagnostic Cognitive Behavioral Therapy Versus Treatment as Usual in Adult Patients With Emotional Disorders in the Primary Care Setting (PsicAP Study): Protocol for a Randomized Controlled Trial

Antonio Cano-Vindel; Roger Muñoz-Navarro; Cristina Mae Wood; Joaquín T Limonero; Leonardo Adrián Medrano; Paloma Ruiz-Rodríguez; Irene Gracia-Gracia; Esperanza Dongil-Collado; Iciar Iruarrizaga; Fernando Chacón; Francisco Santolaya

Background Demand for primary care (PC) services in Spain exceeds available resources. Part of this strong demand is due to the high prevalence of emotional disorders (EDs)—anxiety, depression, and somatic symptom disorders—and related comorbidities such as pain or chronic illnesses. EDs are often under- or misdiagnosed by general practitioners (GPs) and, consequently, treatment is frequently inadequate. Objective We aim to compare the short- and long-term effectiveness of group-delivered transdiagnostic cognitive behavioral therapy (TD-CBT) versus treatment as usual (TAU) in the treatment of EDs in the PC setting in Spain. We also aim to compare the effect of these treatments on disability, quality of life, cognitive-emotional factors, and treatment satisfaction. Methods Here we present the study design of a two-arm, single-blind, randomized controlled trial (N=1126) to compare TAU to TD-CBT for EDs. TAU will consist primarily of pharmacological treatment and practical advice from the GP while TD-CBT will be administered in seven 90-minute group sessions held over a period ranging from 12 to 14 weeks. Psychological assessments are carried out at baseline (ie, pretreatment); posttreatment; and at 3-, 6-, and 12-month follow-up. The study is conducted in approximately 26 PC centers from the National Health System in Spain. Results This study was initiated in December 2013 and will remain open to new participants until recruitment and follow-up has been completed. We expect all posttreatment evaluations to be completed by December 2017, and follow-up will end in December 2018. Conclusions We expect the TD-CBT group to have better results compared to TAU on all posttreatment measures and that this improvement will be maintained during follow-up. This project could serve as a model for use in other areas or services of the National Health System in Spain and even in other countries. ClinicalTrial International Standard Randomized Controlled Trial Number (ISRCTN): 58437086; http://www.isrctn.com/ISRCTN58437086 (Archived by WebCite at http://www.webcitation.org/6mbYjQSn3)


Brain Research | 2001

Effect of local sympathectomy on 24-h changes in mitogenic responses and lymphocyte subset populations in rat submaxillary lymph nodes during the preclinical phase of Freund’s adjuvant arthritis

Ana I. Esquifino; Patricia O. Castrillón; Fernando Chacón; Rodolfo A. Cutrera; Daniel P. Cardinali

Wistar male rats received a bilateral superior cervical ganglionectomy or sham-operation and 10 days later were injected with Freunds complete adjuvant or its vehicle. Two days later, rats were killed at six different time intervals throughout a 24-h cycle. The mitogenic effect of lipopolysaccharide (LPS) and concanavalin A (Con A) and the relative size of lymphocyte subset populations were measured in submaxillary lymph nodes. Cells from sympathectomized lymph nodes showed a lower response to Con A. Freunds adjuvant injection decreased amplitude of daily rhythm in Con A response, an effect prevented by denervation. Generally, ganglionectomy increased Con A response at the early phase of arthritis. Acrophases for Con A and LPS effect occurred at early afternoon and did not change after ganglionectomy. Administration of Freunds adjuvant caused a 10-h advance in acrophase of LPS mitogenic activity, an effect prevented by ganglionectomy. Significant 24-h rhythms were observed in relative size of lymph node B and T cells. Denervation augmented amplitude of rhythm in B cells in adjuvants vehicle-injected rats. As far as T lymphocyte subsets, acrophases occurred at the afternoon (CD4(+) and CD4(+)-CD8(+) cell types) or at night (CD8(+) cell types). Immunization augmented amplitude of 24-h rhythms in CD4(+)-CD8(+) cells regardless of innervation whereas denervation counteracted the suppression of daily rhythm in CD8(+) cells seen in arthritis. The results indicate that some of the changes seen in 24-h organization of immune responses in lymph nodes at an early phase of arthritis are modified by severing the local sympathetic nerves.


Neurosignals | 2002

Effect of Aging on 24-Hour Changes in Dopamine and Serotonin Turnover and Amino Acid and Somatostatin Contents of Rat Corpus striatum

Ana I. Esquifino; Pilar Cano; Fernando Chacón; Carlos F. Reyes Toso; Daniel P. Cardinali

This study examined the 24-hour changes in a number of transmitters in the corpus striatum of young and middle-aged male Wistar rats. The contents of excitatory amino acids (glutamate, aspartate) and inhibitory amino acids (γ-aminobutyric acid, GABA; taurine, glycine) and of somatostatin were measured in 2-month- and 18- to 20-month-old rats killed at six different time points along the 24-hour cycle. The striatal serotonin and dopamine turnover was also measured. Both young and middle-aged rats showed significant 24-hour variations in striatal glutamate and aspartate contents; only in young rats these variations fitted a cosine function, with acrophase during the first part of rest span. Mesor values of striatal excitatory amino acid contents were lowest in middle-aged rats. Significant 24-hour variations in striatal contents of GABA, taurine, and glycine occurred in young rats, while only striatal GABA exhibited 24-hour changes in middle- aged rats (acrophases during the first part of rest span). For every inhibitory transmitter, the mesor values in middle-aged rats were significantly lower than in young rats. The 24-hour variation of the striatal somatostatin content showed acrophase during the first part of rest span, mesor values and amplitude being lowest in middle-aged rats. Aging rats exhibited significantly higher mesor values of striatal serotonin turnover (34% increase) and lower mesor values of dopamine turnover (69% decrease) than their younger counterparts. Some of the circadian modifications of motor function seen in aging rats could be related to the striatal transmitter changes reported herein.


Estudios De Psicologia | 1999

Estudio sobre las motivaciones de una muestra de voluntarios españoles en el campo del SIDA

María L. Vecina; Fernando Chacón

ResumenEste estudio, realizado con una muestra de 112 voluntarios, pretende conocer la influencia de determinadas variables sociodemograficas como la edad, el nivel de estudios, el tiempo de permanencia en una organizacion, etc. en la importancia concedida a las distintas motivaciones para tomar la decision de ser voluntario. Los resultados muestran que la edad, el tipo de organizacion y el tiempo de permanencia en la misma son variables diferenciado ras de las motivaciones de los voluntarios. Tambien muestran cuatro perfiles motivacionales diferentes que se asocian al distinto tiempo de permanencia de los voluntarios.


Violence Against Women | 2016

Moral Absolutism, Self-Deception, and Moral Self-Concept in Men Who Commit Intimate Partner Violence A Comparative Study With an Opposite Sample

María L. Vecina; Fernando Chacón; J. M. Pérez-Viejo

The objective of this study is to show compatible data with the idea that men who commit intimate partner violence are uninhibited about the moral consequences of their behaviors, probably because they feel certainty about the rightness of their moral values and they strongly deceive themselves to maintain a good moral self-concept, and thus a good level of well-being. To do that, we compare their scores with those obtained by an opposite sample regarding the use of violence, made up of professional male psychologists who work in the social field trying to teach others alternative strategies to violence.

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María L. Vecina

Complutense University of Madrid

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Ana I. Esquifino

Complutense University of Madrid

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Pilar Cano

Complutense University of Madrid

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Daniela Marzana

Catholic University of the Sacred Heart

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Elena Marta

Catholic University of the Sacred Heart

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María P. Alvarez

Complutense University of Madrid

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Antonio Cano-Vindel

Complutense University of Madrid

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Jèrôme Flores

Complutense University of Madrid

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