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1.
Ann Oncol ; 29(1): 71-83, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29069302

RESUMEN

Checkpoint receptor blockers, known to act by blocking the pathways that inhibit immune cell activation and stimulate immune responses against tumor cells, have been immensely successful in the treatment of cancer. Among several checkpoint receptors of immune cells, cytotoxic T-lymphocyte-associated protein-4 (CTLA-4), programmed cell death protein-1 (PD-1), T-cell immunoglobulin and ITIM domain (TIGIT), T-cell immunoglobulin-3 (TIM-3) and lymphocyte activation gene 3 (LAG-3) are the most commonly targeted checkpoints for cancer immunotherapy. Six drugs including one CTLA-4 blocker (ipilimumab), two PD-1 blockers (nivolumab and pembrolizumab) and three PD-L1 blockers (atezolizumab, avelumab and durvalumab) are approved for the treatment of different types of cancers including both solid tumors such as melanoma, lung cancer, head and neck cancer, bladder cancer and Merkel cell cancer as well as hematological tumors such as classic Hodgkin's lymphoma. The main problem with checkpoint blockers is that only a fraction of patients respond to the therapy. Insufficient immune activation is considered as one of the main reason for low response rates and combination of checkpoint blockers has been proposed to increase the response rates. The combination of checkpoint blockers was successful in melanoma but had significant adverse events. A combination that is selected based on the mechanistic differences between checkpoints and the differences in expression of checkpoints and their ligands in the tumor microenvironment could have a synergistic effect in a given cancer subtype and also have a manageable safety profile. This review aims to help in design of optimal checkpoint blocker combinations by discussing the mechanistic details and outlining the subtle differences between major checkpoints targeted for cancer immunotherapy.


Asunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Inmunoterapia/métodos , Neoplasias/inmunología , Neoplasias/terapia , Animales , Humanos
2.
Faraday Discuss ; 191: 373-389, 2016 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-27460036

RESUMEN

We report on the fabrication of oriented anisotropic metal nanoparticle thin films made by Grazing Incidence Spraying (GIS) and on the anisotropic plasmonic properties of the resulting thin films. Gold nanorods of two different aspect ratios and silver nanowires were self-assembled as a uniaxially aligned monolayer with the GIS approach. In particular, we examine the influence of the nanowire/nanorod length and diameter on the degree of ordering determined by electron microscopy pictures. Furthermore, we show that the anisotropy of the optical properties (probed by polarized UV-visible-near infrared spectroscopy) strongly depend on the quality of alignment. The prepared monolayer thin films have an orientation order parameter of up to 0.83 for silver nanowires, which is reflected in an optical anisotropy of 0.57 in the UV-visible and 0.76 in the near infrared through the selective excitation of transverse and longitudinal surface plasmon resonance modes. The electronic transport in oriented silver nanowire monolayers is also shown to be highly directional, with the sheet resistance varying over almost an order of magnitude depending on the transport direction. Such anisotropic conductive plasmonic thin films may find applications in various fields like biochemical sensing, energy transport and harvesting or optoelectronic devices.

3.
J Viral Hepat ; 18(10): e516-22, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21914071

RESUMEN

Liver steatosis is a main histopathological feature of Hepatitis C (HCV) infection because of genotype 3. Steatosis and/or mechanisms underlying steatogenesis can contribute to hepatocarcinogenesis. The aim of this retrospective study was to assess the impact of infection with HCV genotype 3 on hepatocellular carcinoma (HCC) occurrence in patients with ongoing HCV cirrhosis. Three hundred and fifty-three consecutive patients (193 men, mean age 58 ± 13 years), with histologically proven HCV cirrhosis and persistent viral replication prospectively followed and screened for HCC between 1994 and 2007. Log-rank test and Cox model were used to compare the actuarial incidence of HCC between genotype subgroups. The patients infected with a genotype 3 (n = 25) as compared with those infected with other genotypes (n = 328) had a lower prothrombin activity [78 (interquartile range 60-85) vs 84 (71-195) %, P = 0.03] and higher rate of alcohol abuse (48%vs 29%, P = 0.046). During a median follow-up of 5.54 years [2.9-8.6], 11/25 patients (44%) and 87/328 patients (26%) with a genotype 3 and non-3 genotype, respectively, develop a HCC. HCC incidences were significantly different among the genotype subgroups (P = 0.001). The 5-year occurrence rate of HCC was 34% (95% CI, 1.3-6.3) and 17% (95% CI, 5.7-9.2) in genotype 3 and non-3 genotype groups, respectively (P = 0.002). In multivariate analysis, infection with a genotype 3 was independently associated with an increased risk of HCC occurrence [hazard ratio 3.54 (95% CI, 1.84-6.81), P = 0.0002], even after adjustment for prothrombin activity and alcohol abuse [3.58 (1.80-7.13); P = 0.003]. For patients with HCV cirrhosis and ongoing infection, infection with genotype 3 is independently associated with an increased risk of HCC development.


Asunto(s)
Carcinoma Hepatocelular/epidemiología , Hepacivirus/clasificación , Hepacivirus/patogenicidad , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/virología , Cirrosis Hepática/complicaciones , Cirrosis Hepática/virología , Anciano , Hígado Graso/complicaciones , Hígado Graso/patología , Hígado Graso/virología , Femenino , Genotipo , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/patología , Humanos , Incidencia , Cirrosis Hepática/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
4.
Nurse Educ Today ; 106: 105042, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34274748

RESUMEN

BACKGROUND: The growing prevalence of chronic illnesses requires nurses to support self-management and help patients integrate the chronic illness into their life. To our knowledge there are currently no training programs that combine the necessary components to adequately enhance nurses' competencies in self-management support. OBJECTIVE: The systematic development and validation of a need-supportive training in self-management support for nurses. DESIGN: A three-phased study, according to van Meijel et al. (2004), with collection of building blocks, design, and validation of the need-supportive character of the training. SETTING AND PARTICIPANTS: Eight training groups with 30 nurses, 34 nursing students and nine social healthcare workers from different nursing colleges in Flanders, Belgium. METHODS: In phase one a literature review, current practice analysis, and problem and needs analysis were performed. In phase two, the INTENSS training intervention was developed, framed within the Self-Determination Theory and the 5A's-Model. The training consisted of a basic training module and a video-interaction guidance module. The intervention was subsequently tested in eight training groups (N = 73). Participants provided feedback during focus group discussions. The intervention was cyclically adapted to trainees' experiences and suggestions. In phase three, we evaluated the need-supportive character of the training intervention. RESULTS: Phase one indicated the need for training, since nurses' application of self-management support was limited and practiced from a narrow medical point of view. In phase two we developed a theory-driven and multifaceted training, building on attitude, knowledge, skills and reflection in the training. The training was framed within the Self-Determination Theory both at the didactical level as well as on content and format. Overall, participants appreciated the building blocks of the training as supporting their basic needs for autonomy, relatedness and competence. CONCLUSIONS: INTENSS, a multifaceted need-supportive training in self-management support was developed, successfully taking into account participants' needs.


Asunto(s)
Enfermeras y Enfermeros , Automanejo , Estudiantes de Enfermería , Actitud del Personal de Salud , Enfermedad Crónica , Humanos
5.
Rev Med Liege ; 64(7-8): 414-7, 2009.
Artículo en Francés | MEDLINE | ID: mdl-19777924

RESUMEN

Solitary lipoma is the most frequent soft tissue tumor, often appearing between 40 and 60 years of age. It is described as "giant" beyond 1 kg of weight and 10 cm of diameter. Its volume is the source of a good many problems in social life (camouflage, difficulties to dress) and causes multiple health problems such as pain, difficulties to sleep, compressions of nerves or vital structures, infections, etc. The diagnosis is primarily clinical. However, it is necessary to systematically exclude a malignant process. Surgical biopsy is recommended if the diagnosis cannot be asserted by the clinic or an imagery. The therapeutic attitude is abstention in case of small volume without functional impairment. Otherwise, total surgical excision is indicated with pathological analysis. We describe the clinical history of a patient suffering from a giant dorsal lipoma.


Asunto(s)
Dorso/patología , Dorso/cirugía , Lipoma/patología , Adulto , Biopsia , Diagnóstico Diferencial , Femenino , Humanos , Lipoma/complicaciones , Lipoma/cirugía , Calidad de Vida , Escápula/patología , Resultado del Tratamiento
6.
Eur J Vasc Endovasc Surg ; 36(4): 449-51, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18524650

RESUMEN

INTRODUCTION: Groin lymphatic fistulas are a troublesome finding after limb revascularization surgery. Its management represents a difficult task for the clinician. REPORT: We report our experience in the treatment of such a condition with negative-pressure wound therapy (NPWT) in a 70-year-old man which benefited from extra-anatomic prosthetic axillofemoral bypass. After a week of treatment, the fistula dried up and closure was obtained with simple suture under local anaesthesia. Follow-up at 9 months showed stable coverage without any sign of leakage. DISCUSSION: This study depicts NPWT as an effective non-invasive treatment in the management of groin lymphocutaneous fistula.


Asunto(s)
Fístula Cutánea/terapia , Fístula/terapia , Ingle , Enfermedades Linfáticas/terapia , Terapia de Presión Negativa para Heridas , Anciano , Implantación de Prótesis Vascular/efectos adversos , Arteria Femoral/cirugía , Humanos , Masculino
7.
Acta Chir Belg ; 108(3): 298-303, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18710102

RESUMEN

As the incidence of breast cancer increases, breast reconstruction is more and more often proposed and its indications are viewed in terms of quality of life. In the past, delayed reconstruction was the rule. Progress in reconstructive techniques currently allows performing immediate reconstruction in selected cases, even when the operative field has to be irradiated. These new techniques generally improve the result of breast reconstruction. Moreover, expansion of screening techniques allows detection of small tumors for which a conservative excision is sufficient. Nevertheless, this kind of less aggressive surgery may require a reconstructive procedure in order to maximise the aesthetic result.


Asunto(s)
Neoplasias de la Mama/cirugía , Carcinoma/cirugía , Mamoplastia/métodos , Implantes de Mama , Femenino , Humanos , Mamoplastia/normas , Mamoplastia/tendencias , Satisfacción del Paciente , Radioterapia Adyuvante , Colgajos Quirúrgicos/irrigación sanguínea , Colgajos Quirúrgicos/fisiología , Factores de Tiempo
8.
Acta Chir Belg ; 107(6): 703-5, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18274191

RESUMEN

The authors report their experience in the treatment of a posttraumatic enterocutaneous fistula with negative-pressure therapy. After sustaining an epigastric shot wound, a 33-year-old woman underwent three consecutive laparotomies, which eventually led to an open abdomen with the interposition of a surgical mesh. Enterocutaneous fistulae were subsequently documented and vacuum-assisted closure therapy was instituted along with total parenteral nutrition and systemic antibiotics. Development of a suitable granulation bed and closure of the fistulae were noted after two weeks of treatment and a split-thickness skin graft was applied to the wound. Follow-up at 8 months showed stable coverage and a return to normal enteral feeding.


Asunto(s)
Fístula Intestinal/cirugía , Terapia de Presión Negativa para Heridas , Adulto , Femenino , Tejido de Granulación/patología , Humanos , Nutrición Parenteral , Trasplante de Piel
9.
Neurobiol Aging ; 26(1): 103-14, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15585350

RESUMEN

Age-dependent cognitive impairments have been correlated with functional and structural modifications in the hippocampal formation. In particular, the brain endogenous steroid pregnenolone-sulfate (Preg-S) is a cognitive enhancer whose hippocampal levels have been linked physiologically to cognitive performance in senescent animals. However, the mechanism of its actions remains unknown. Because neurogenesis is sensitive to hormonal influences, we examined the effect of Preg-S on neurogenesis, a novel form of plasticity, in young and old rats. We demonstrate that in vivo infusion of Preg-S stimulates neurogenesis and the expression of the polysialylated forms of NCAM, PSA-NCAM, in the dentate gyrus of 3- and 20-month-old rats. These influences on hippocampal plasticity are mediated by the modulation of the gamma-aminobutyric acid receptor complex A (GABA(A)) receptors present on hippocampal neuroblasts. In vitro, Preg-S stimulates the division of adult-derived spheres suggesting a direct influence on progenitors. These data provide evidence that neurosteroids represent one of the local secreted signals controlling hippocampal neurogenesis. Thus, therapies which stimulate neurosteroidogenesis could preserve hippocampal plasticity and prevent the appearance of age-related cognitive disturbances.


Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Hipocampo/citología , Molécula L1 de Adhesión de Célula Nerviosa/metabolismo , Plasticidad Neuronal/efectos de los fármacos , Neuronas/efectos de los fármacos , Pregnenolona/farmacología , Ácidos Siálicos/metabolismo , Factores de Edad , Análisis de Varianza , Animales , Bromodesoxiuridina/metabolismo , Recuento de Células/métodos , Relación Dosis-Respuesta a Droga , Hipocampo/efectos de los fármacos , Hipocampo/fisiología , Inyecciones Intraventriculares/métodos , Masculino , Microscopía Inmunoelectrónica/métodos , Neuronas/metabolismo , Neuronas/ultraestructura , Ratas , Ratas Sprague-Dawley , Receptores de GABA-A/metabolismo , Factores de Tiempo
10.
Hypertension ; 21(5): 714-23, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8491506

RESUMEN

We report on five 6-month experiments during which five colonies of four male and four female rats were exposed to psychosocial stress. Monthly blood pressure measurements by a tail-cuff method showed a modest (10 mm Hg) increase in two studies using Sprague-Dawley rats. In two further studies using the more aggressive Long-Evans strain, terminal direct carotid arterial pressures were taken as well, and in one study the differences exceeded 20 mm Hg. A fifth study used the Wistar-Kyoto, hyperactive (WKHA) strain developed by Hendley, and no differences were observed. Heart and adrenal weights; adrenal catecholamine synthetic enzymes; and heart, aortic, and kidney histology were measured and showed significant changes, which for the most part paralleled blood pressure changes. Social instability and the associated blood pressure changes were made more severe by periodic mixing of males from different colonies. This had no effect on the peaceable WKHA rats, some effect on the Sprague-Dawley rats, and a severe effect on the Long-Evans rats. The WKHA rats failed to show blood pressure changes despite stress-induced increases in heart and adrenal weights. Thus, different types of psychosocial stress and different genetics combine to induce a variety of neuroendocrine changes, not all of which necessarily lead to increased blood pressure.


Asunto(s)
Presión Sanguínea , Hipertensión/etiología , Ratas Endogámicas , Estrés Psicológico/complicaciones , Glándulas Suprarrenales/metabolismo , Glándulas Suprarrenales/patología , Agresión/fisiología , Animales , Conducta Animal , Peso Corporal , Catecolaminas/biosíntesis , Enfermedad Crónica , Femenino , Hipertensión/fisiopatología , Masculino , Miocardio/patología , Tamaño de los Órganos , Ratas , Ratas Endogámicas WKY , Ratas Sprague-Dawley , Valores de Referencia , Estrés Psicológico/psicología
11.
Clin Exp Metastasis ; 18(2): 171-8, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11235993

RESUMEN

Several matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) were studied in highly invasive (MDA-MB-231) and slightly invasive (MCF-7, T47D, BT-20) breast cancer cell lines. Investigations were carried out at the protein level and/or at the mRNA level, either in cells cultured as monolayers on plastic, or in cells seeded on a thin layer of Matrigel basement membrane matrix. Analysis of MMP expression by RT-PCR showed expression of MMP-1. MMP-3, and MMP-13 in highly invasive MDA-MB-231 cells, but not in slightly invasive cell lines. The extracellular secretion of MMP-1 and MMP-3 by MDA-MB 231 cells could be also shown by ELISA. TIMP-1 and TIMP-2 mRNAs were found in all cell lines, however, the extracellular secretion of both TIMPs was much higher in MDA-MB-231 cells than in the other cell lines. When the cells were cultured on Matrigel matrix, MMP-9 expression was induced in MDA-MB-231 cells only, as assessed by RT-PCR and zymography experiments. The invasive potential of MDA-MB-231 cells evaluated in vitro through Matrigel was significantly inhibited by the MMP inhibitor BB-2516, by 25% and 50% at the concentrations of 2 x 10(-6) M and 10(-5) M, respectively. In conclusion, our data show that highly invasive MDA-MB-231 cells but not slightly invasive T47D, MCF-7 and BT-20 cells express MMP-1, MMP-3, MMP-9 and MMP-13. MMP-9 which is specifically up-regulated by cell contact to Matrigel, may play a key role in the invasiveness of MDA-MB-231 cells through basement membranes.


Asunto(s)
Neoplasias de la Mama/enzimología , Metaloproteinasas de la Matriz/metabolismo , Invasividad Neoplásica , Secuencia de Bases , Membrana Basal/enzimología , Neoplasias de la Mama/patología , Colágeno , Cartilla de ADN , Combinación de Medicamentos , Ensayo de Inmunoadsorción Enzimática , Ácidos Hidroxámicos/farmacología , Laminina , Inhibidores de la Metaloproteinasa de la Matriz , Proteoglicanos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Inhibidores Tisulares de Metaloproteinasas/metabolismo , Células Tumorales Cultivadas
12.
Psychoneuroendocrinology ; 22(8): 563-73, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9483702

RESUMEN

Stress in males via the hypothalamic-pituitary-adrenal (HPA) axis may set into motion varied physiological alterations, including dysfunction of the hypothalamic-pituitary-gonadal (HPG) axis. However, the influence of the HPA on the HPG axis may not always be inhibitory. Presence or absence of stimuli of sexual significance that typically activates the HPG axis may alter the influence of the adrenal axis on gonadal axes. In this project, we used male rats and chronic social stimulation that included brief or extended periods with female rats to examine HPA-HPG axes interactions. In experiment 1, we used intact males and a 'chronic social stress' paradigm developed in our previous research that induces social instability by daily changing the membership of group-housed males with females. Thymus weight was reduced and corticosterone levels were marginally increased by chronic social stress, indicating a HPA axis hyperactivity. The HPG axis was also activated as shown by the increased weight of the androgen-sensitive sex structures. These results indicate that when these two axes are stimulated together, neither interferes with nor suppresses activities of the other. Implants of corticosterone pellets to adrenalectomized animals that maintained constant, high corticosterone levels failed to reverse the gonadal hyperactivity induced by sexual stimulation. In a second experiment, we studied the influence of different intensity of sexual stimulations on HPA-HPG axes interactions. Increased corticosterone levels and adrenal weight, indicating a HPA hyperactivity, failed to inhibit HPG hyperactivity as measured by the increased sexual organs weight, whatever the sexual intensity of the stimulation. This work demonstrates that the gonadal axis is freed from suppression when sexual stimulation occurs together with stress. The general conclusion is that the nature of complex social settings is important in determining interactions between the two neuroendocrine axes.


Asunto(s)
Glándulas Suprarrenales/fisiopatología , Conducta Social , Estrés Psicológico/fisiopatología , Testículo/fisiopatología , Adrenalectomía , Animales , Peso Corporal/fisiología , Enfermedad Crónica , Corticosterona/administración & dosificación , Corticosterona/sangre , Corticosterona/farmacología , Implantes de Medicamentos , Femenino , Masculino , Tamaño de los Órganos/fisiología , Próstata/patología , Próstata/fisiopatología , Ratas , Ratas Wistar , Conducta Sexual Animal/fisiología , Estrés Psicológico/patología , Testículo/patología
13.
Brain Res ; 649(1-2): 348-52, 1994 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-7953651

RESUMEN

Using social instability and cohabitation with females as chronic stress, we observed that neuroendocrine systems were differentially activated according to the experimental design. We show here that amphetamine self-administration, a paradigm to study the reinforcing effects of psychostimulants, is also differentially affected by these conditions. Coexistence with females increases amphetamine self-administration and this effect is reduced when social instability is superimposed. On the other hand, locomotor response to amphetamine is not modified by either social factor, suggesting a specific involvement of a subset of dopaminergic neurons.


Asunto(s)
Anfetamina/administración & dosificación , Estrés Psicológico/psicología , Anfetamina/farmacología , Animales , Ambiente , Femenino , Masculino , Actividad Motora/efectos de los fármacos , Ratas , Ratas Wistar , Autoadministración , Conducta Social
14.
Brain Res ; 547(1): 7-12, 1991 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-1860073

RESUMEN

In this study, we attempted to find out whether a social stress-induced increase in the vulnerability to acquire amphetamine self-administration was associated with a change in number of hippocampal corticosteroid receptors. This was examined in two types of sex-mixed colonies of rats. Animals were maintained for 4 weeks in: (1) 'stable social condition', membership did not change after constitution of the colony; (2) 'unstable social condition', the males were changed daily in a random design. The animals living in the 'stable social' conditions had: (1) a lower number of hippocampal type I corticosteroid receptors; (2) a longer duration of the increase in plasma corticosterone after exposure to novelty; (3) a higher vulnerability to acquire amphetamine self-administration. These findings suggest that a decrease in hippocampal type I corticosteroid receptors may be one of the biological mechanisms responsible for the impaired corticosterone feedback control observed in vulnerable animals. These findings throw more light on the role of hypothalamo-pituitary-adrenal axis in the modulation of adaptive behavior. The availability of drugs which are specific for corticosteroid receptors could represent a new approach to the therapy of certain behavioral disturbances.


Asunto(s)
Anfetamina/farmacología , Corticosterona/fisiología , Receptores de Glucocorticoides/metabolismo , Estrés Psicológico/psicología , Adrenalectomía , Animales , Ambiente , Retroalimentación , Femenino , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Sistema Hipotálamo-Hipofisario/fisiopatología , Masculino , Sistema Hipófiso-Suprarrenal/fisiopatología , Ratas , Ratas Endogámicas , Autoadministración , Estrés Psicológico/metabolismo
15.
Eur Cytokine Netw ; 5(5): 449-53, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7880975

RESUMEN

After one hour incubation with interleukin-1 beta (IL-1 beta), the uptake of alpha-(methylamino) isobutyric acid (MeAIB) by human osteoarthritic synovial cells appeared significantly increased. This effect, observed with 0.1 to 5 ng/ml of cytokine, was inhibited by cycloheximide, indicating that protein synthesis is involved. In addition, this effect seems mediated by a pertussis toxin-sensitive G protein. Finally, intracellular cAMP concentration measurements, the use of a phorbol ester, protein kinase inhibitors and forskolin+3-isobutyl-1-methylxantine (IBMX) provided evidence that a cAMP-dependent protein kinase is associated with interleukin-1 beta-mediated alpha-(methylamino) isobutyric acid uptake.


Asunto(s)
AMP Cíclico/metabolismo , Interleucina-1/farmacología , Sulfonamidas , Membrana Sinovial/efectos de los fármacos , Membrana Sinovial/metabolismo , beta-Alanina/análogos & derivados , Transporte Biológico Activo/efectos de los fármacos , Células Cultivadas , Proteínas Quinasas Dependientes de AMP Cíclico/efectos adversos , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Cicloheximida/farmacología , Proteínas de Unión al GTP/metabolismo , Humanos , Interleucina-1/administración & dosificación , Isoquinolinas/farmacología , Cinética , Osteoartritis/metabolismo , Toxina del Pertussis , Biosíntesis de Proteínas , Transducción de Señal , Factores de Virulencia de Bordetella/farmacología , beta-Alanina/farmacocinética
16.
Life Sci ; 63(2): 87-96, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9674942

RESUMEN

In order to study the genetic factors involved in the neuroendocrine responses to stress, we have compared the intensity of the hypothalamic-pituitary-adrenal (HPA) axis and sympathetic nervous system activation following a 60 minute-restraint stress or after a 10 minute-exposure to a novel environment in three rat strains : outbred Wistar, inbred Brown Norway and Fischer 344, and F1 hybrid Brown Norway x Fischer 344 rats. The basal activity of the HPA axis did not differ between the four groups of rats whereas Brown Norway rats had the lowest release of corticosterone following restraint stress. Although differences in plasma adrenocorticotropic hormone failed to reach significance after exposure to a novel environment, the lowest level of corticosterone was found in Brown Norway rats. This lower release of corticosterone in Brown Norway rats has probably an adrenal origin as suggested by the ratios of corticosterone to ACTH levels following exposure to a novel environment: 632 +/- 222, 200 +/- 45, 636 +/- 89, 258 +/- 65 in Wistar, Brown Norway, Fischer 344 and F1 hybrids, respectively. This trait was dominant over the "adrenal responsive" phenotype of the Fischer 344 rat strain. In response to novelty, the lowest levels of prolactin and renin activity were found in plasma of Brown Norway and Wistar rats and the highest in Fischer 344 and F1 hybrid Brown Norway x Fischer 344 rats, the "high response" phenotype of the Fischer 344 strain being dominant. No strain-related difference was found in plasma glucose and either adrenal tyrosine hydroxylase or phenylethanolamine N-methyl transferase activity. Taken together, these data suggest that 1) genetic factors might contribute to the interindividual differences in neuroendocrine responses to stress and 2) subsets of these responses are controlled by specific genetic factors.


Asunto(s)
Sistema Hipotálamo-Hipofisario/fisiopatología , Sistema Hipófiso-Suprarrenal/fisiopatología , Estrés Fisiológico/fisiopatología , Sistema Nervioso Simpático/fisiopatología , Glándulas Suprarrenales/anatomía & histología , Glándulas Suprarrenales/enzimología , Médula Suprarrenal/metabolismo , Médula Suprarrenal/fisiopatología , Hormona Adrenocorticotrópica/sangre , Animales , Glucemia/metabolismo , Peso Corporal/fisiología , Corticosterona/sangre , Sistema Hipotálamo-Hipofisario/metabolismo , Masculino , Tamaño de los Órganos/fisiología , Feniletanolamina N-Metiltransferasa/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Prolactina/sangre , Ratas , Ratas Endogámicas BN , Ratas Endogámicas F344 , Ratas Wistar , Renina/sangre , Estrés Fisiológico/sangre , Tirosina 3-Monooxigenasa/metabolismo
17.
Life Sci ; 50(10): 723-31, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1738299

RESUMEN

The influence of a chronic social stress upon immunity was investigated in Wistar rats, submitted for four weeks to two different behavioral situations, balanced in a factorial design: housing with three females and membership rotation. The combination of these two factor led to adrenal enlargement (43.3%), thymus involution (39.5%) and increased basal corticosterone levels, all indices of activation of the hypothalamic-hypophysis-adrenal axis. However, neither natural killer cell activity, splenocyte reactivity to mitogen nor the rate of spontaneous development of antibodies against Mycoplasma pulmonis, a common pathogen of the respiratory tract, were changed in the endocrine activated animals. Analysis of the data on kinetics of stress at 1, 7 and 28 days after the initial mixing of the animals gave the same results. These data question the immunosuppressant activity usually conferred to corticosteroids, at least when adrenal hyperactivity is induced by chronic environmental stressors.


Asunto(s)
Corticosterona/fisiología , Estrés Psicológico/inmunología , Estrés Psicológico/fisiopatología , Glándulas Suprarrenales/patología , Animales , Anticuerpos Antibacterianos/biosíntesis , Enfermedad Crónica , Corticosterona/metabolismo , Femenino , Células Asesinas Naturales/fisiología , Activación de Linfocitos/fisiología , Masculino , Mycoplasma/inmunología , Tamaño de los Órganos , Ratas , Ratas Endogámicas , Bazo/inmunología , Bazo/patología , Estrés Psicológico/patología , Timo/patología
18.
Physiol Behav ; 58(6): 1181-8, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8623018

RESUMEN

The role of stress in the etiology of high blood pressure and the biological mechanisms involved are still not clear. We have recently developed a paradigm of chronic social stress based on social instability and cohabitation with females, in which the different neuroendocrine responses to stress can be independently triggered. In this work, we used a telemetry technique to record blood pressure and heart rate chronically in freely moving undisturbed rats to study the influence of chronic social stress on blood pressure and heart rate in normotensive rats (Wistar and Long-Evans) and in Borderline Hypertensive Rats (BHR). No increase of blood pressure could be seen for one month of social stress in either strain. Wistar and Long-Evans rats were fully sensitive to social pressure, as shown by the changes in body weight, but may lack a specific vulnerability of the cardiovascular system. Conversely, Borderline Hypertensive rats have the genetic predisposition to develop hypertension but do not appear to be sensitive to social stimulations in the present experimental conditions. The experimental protocol used here should allow further investigation of the various possible sources of failure to induce chronic cardiovascular changes by social stress, such as blood pressure measurement techniques, social stress protocols, and genetic aspects of psychobiological and cardiovascular vulnerability to stress.


Asunto(s)
Presión Sanguínea/fisiología , Ritmo Circadiano/fisiología , Frecuencia Cardíaca/fisiología , Hipertensión/fisiopatología , Relaciones Interpersonales , Animales , Femenino , Masculino , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Ratas Wistar , Factores de Tiempo
19.
Physiol Behav ; 47(6): 1099-105, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1975698

RESUMEN

After four weeks of individual housing, male Wistar rats (selected for high or low spontaneous aggressiveness by multiple round-robin encounters) were housed three per cage and submitted to four weeks of chronic social stress consisting of changing membership in the social groups by daily rotation of the animals among cages every day according to a random permutation procedure. In addition, half the males in each condition were housed with three females. Each environmental condition triggered different neuroendocrine changes. Cohabitation with females increased the hypothalamo-pituitary-adrenocortical axis activity, including enlargement of adrenals and increased circulating corticosterone levels. On the other hand, daily rotation of the rats between different social groups activated part of the sympathetic nervous system, such as increased phenylethanolamine N-methyl transferase (PNMT) activity in the adrenals. The level of aggressiveness, however, had no direct influence but interacted with environmental factors on such neuroendocrine measures as circulating testosterone or plasma renin activity. These results indicate that during chronic stress, there is no single, unique response by the animal, but a highly complex set of neuroendocrine changes, dependent on the interaction between individual characteristics (the level of aggressiveness is an example) and situational factors.


Asunto(s)
Nivel de Alerta/fisiología , Sistema Hipotálamo-Hipofisario/fisiología , Sistema Hipófiso-Suprarrenal/fisiología , Medio Social , Agresión/fisiología , Conducta Agonística/fisiología , Animales , Corticosterona/sangre , Femenino , Feniletanolamina N-Metiltransferasa/fisiología , Ratas , Ratas Endogámicas , Conducta Sexual Animal/fisiología , Sistema Nervioso Simpático/fisiología , Tirosina 3-Monooxigenasa/fisiología
20.
Neurotox Res ; 6(7-8): 571-80, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15639789

RESUMEN

Environmental challenges profoundly modify phenotypes and disrupt inherent developmental programs both at functional and structural levels. As an example, we have studied the impact of these environmental influences on adult neurogenesis in the dentate gyrus. Neurogenesis results from an inherent program, participates to hippocampal network organization and, as a consequence, to the various functional abilities depending on this region, including memories. In preclinical studies of aging we have shown that phenotypes vulnerable to the development of spatial memory disorders are characterized by lower hippocampal neurogenesis. We have hypothesized that these interindividual variations in functional expression of neurogenesis in senescent subjects could be predicted early in life. Indeed, a behavioral response (novelty-induced locomotor reactivity) and a biological trait (hypothalamo-pituitary-adrenal axis activity), which are predictive of cognitive impairments later in life, are related to neurogenesis in young adult rats. This suggests that subjects starting off with an impaired neurogenesis, here rats that are high reactive to stress, are predisposed for the development of age-related cognitive disorders. We have further shown that these inter-individual differences result from early deleterious life events. Indeed, prenatal stress orients neurogenesis in pathological ways for the entire life, and precipitates age-related cognitive impairments. Altogether these data suggest first that hippocampal neurogenesis plays a pivotal role in environmentally-induced vulnerability to the development of pathological aging, and second that environmental challenges and life events orient structural developments, leading to different phenotypes.


Asunto(s)
Señales (Psicología) , Ambiente , Hipocampo/citología , Orientación/fisiología , Animales , Diferenciación Celular/fisiología , Conducta Exploratoria/fisiología , Hipocampo/fisiología , Humanos , Conducta Espacial/fisiología , Tiempo
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