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1.
Am J Transplant ; 16(9): 2574-88, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26932231

RESUMEN

Fibrosis is a major component of chronic cardiac allograft rejection. Although several cell types are able to produce collagen, resident (donor-derived) fibroblasts are mainly responsible for excessive production of extracellular matrix proteins. It is currently unclear which cells regulate production of connective tissue elements in allograft fibrosis and how basophils, as potential producers of profibrotic cytokines, are involved this process. We studied this question in a fully MHC-mismatched model of heart transplantation with transient depletion of CD4(+) T cells to largely prevent acute rejection. The model is characterized by myocardial infiltration of leukocytes and development of interstitial fibrosis and allograft vasculopathy. Using depletion of basophils, IL-4-deficient recipients and IL-4 receptor-deficient grafts, we showed that basophils and IL-4 play crucial roles in activation of fibroblasts and development of fibrotic organ remodeling. In the absence of CD4(+) T cells, basophils are the predominant source of IL-4 in the graft and contribute to expansion of myofibroblasts, interstitial deposition of collagen and development of allograft vasculopathy. Our results indicated that basophils trigger the production of various connective tissue elements by myofibroblasts. Basophil-derived IL-4 may be an attractive target for treatment of chronic allograft rejection.


Asunto(s)
Basófilos/inmunología , Rechazo de Injerto/etiología , Cardiopatías/etiología , Trasplante de Corazón/efectos adversos , Interleucina-4/fisiología , Aloinjertos , Animales , Femenino , Fibrosis/etiología , Fibrosis/patología , Rechazo de Injerto/patología , Supervivencia de Injerto , Cardiopatías/patología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados
2.
Neuroscience ; 281: 35-43, 2014 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-25241066

RESUMEN

Withdrawal from amphetamine is associated with increased anxiety and sensitivity to stressors which are thought to contribute to relapse. Rats undergoing amphetamine withdrawal fail to exhibit stress-induced increases in serotonin (5-HT) release in the ventral hippocampus and show heightened anxiety-like behaviors. Therefore, we tested the hypothesis that reducing 5-HT levels in the ventral hippocampus is a causal mechanism in increasing anxiety-like behaviors during amphetamine withdrawal. First, we tested whether reducing 5-HT levels in the ventral hippocampus directly increases anxiety behavior. Male rats were bilaterally infused with 5,7-dihydroxytryptamine (5,7-DHT) into the ventral hippocampus, which produced a 83% decrease in ventral hippocampus 5-HT content, and were tested on the elevated plus maze (EPM) for anxiety-like behavior. Reducing ventral hippocampus 5-HT levels decreased the time spent in the open arms of the maze, suggesting that diminished ventral hippocampus 5-HT levels increases anxiety-like behavior. Next, we tested whether increasing 5-HT levels in the ventral hippocampus reverses anxiety behavior exhibited by rats undergoing amphetamine withdrawal. Rats were treated daily with either amphetamine (2.5-mg/kg, i.p.) or saline for 2weeks, and at 2weeks withdrawal, were infused with the selective serotonin reuptake inhibitor paroxetine (0.5µM) bilaterally into the ventral hippocampus and tested for anxiety-like behavior on the EPM. Rats pre-treated with amphetamine exhibited increased anxiety-like behavior on the EPM. This effect was reversed by ventral hippocampus infusion of paroxetine. Our results suggest that 5-HT levels in the ventral hippocampus are critical for regulating anxiety behavior. Increasing 5-HT levels during withdrawal may be an effective strategy for reducing anxiety-induced drug relapse.


Asunto(s)
Trastornos Relacionados con Anfetaminas/metabolismo , Ansiedad/metabolismo , Hipocampo/metabolismo , Serotoninérgicos/farmacología , Serotonina/metabolismo , Síndrome de Abstinencia a Sustancias/metabolismo , 5,7-Dihidroxitriptamina/administración & dosificación , 5,7-Dihidroxitriptamina/farmacología , Anfetamina/administración & dosificación , Anfetamina/farmacología , Animales , Ansiedad/prevención & control , Estimulantes del Sistema Nervioso Central/administración & dosificación , Estimulantes del Sistema Nervioso Central/farmacología , Modelos Animales de Enfermedad , Hipocampo/efectos de los fármacos , Masculino , Paroxetina/administración & dosificación , Paroxetina/farmacología , Ratas , Ratas Sprague-Dawley , Serotoninérgicos/administración & dosificación
3.
Mucosal Immunol ; 7(1): 188-99, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23757302

RESUMEN

Basophils have been recognized as important inducers of T helper type 2 (Th2) responses. Using the colitis model of adoptive transfer of CD4(+) CD62L(+) T cells into lymphopenic hosts, we have analyzed how basophils regulate T-cell responses and modulate disease activity. Transferred T cells rapidly proliferate, produce large amounts of interleukin (IL)-3, and expand the number of basophils in an IL-3-dependent manner. Depletion of basophils with two different antibodies substantially upregulated Th1 cytokines in transferred T cells at day 8. Increased Th1 cytokine expression persisted until the end of the experiment when basophil-depleted mice showed exacerbation of colitis with more severe loss of weight, histological damage, colonic leukocyte infiltration, and expression of pro-inflammatory cytokines. In vitro, we show that basophil-derived IL-4 and IL-6 downregulates expression of interferon-γ, IL-2, and tumor necrosis factor in T cells. These data show a beneficial role of basophils in a T-cell driven model of autoimmunity.


Asunto(s)
Basófilos/inmunología , Colitis/inmunología , Linfocitos T/inmunología , Traslado Adoptivo , Animales , Basófilos/metabolismo , Colitis/genética , Colitis/metabolismo , Citocinas/sangre , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Linfopenia/inmunología , Linfopenia/metabolismo , Masculino , Ratones , Ratones Noqueados , Fenotipo , Linfocitos T/metabolismo , Células TH1/inmunología , Células TH1/metabolismo
4.
Br J Cancer ; 108(7): 1408-14, 2013 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-23511562

RESUMEN

BACKGROUND: There exists evidence that body mass index (BMI) impacts on the efficacy of aromatase inhibitors in patients with breast cancer. The relationship between BMI and the efficacy of tamoxifen is conflicting. We investigated the impact of BMI on the efficacy of single tamoxifen and tamoxifen plus an aromatase inhibitor in the well-defined prospective study population of the ABCSG-06 trial. METHODS: ABCSG-06 investigated the efficacy of tamoxifen vs tamoxifen plus aminoglutethimide in postmenopausal women with hormone receptor-positive breast cancer. Taking BMI at baseline, patients were classified as normal weight (BMI=18.5-24.9 kg m(-)(2)), overweight (BMI=25-29.9 kg m(-)(2)), and obese (30 kg m(-)(2)) according to WHO criteria. RESULTS: Overweight+obese patients had an increased risk for distant recurrences (hazard ratio (HR): 1.51; Cox P=0·018) and a worse overall survival (OS; HR: 1·49; Cox P=0·052) compared with normal weight patients. Analysing patients treated with single tamoxifen only, no difference between overweight+obese patients and normal weight patients regarding distant recurrence-free survival (HR: 1.35; Cox P=0·24) and OS (HR: 0.99; Cox P=0·97) could be observed. In contrast, in the group of patients treated with the combination of tamoxifen plus aminoglutethimide, overweight+obese patients had an increased risk for distant recurrences (1.67; Cox P=0·03) and a worse OS (1.47; Cox P=0·11) compared with normal weight patients. CONCLUSION: BMI impacts on the efficacy of aromatase inhibitor-based treatment but not single tamoxifen.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Sobrepeso/fisiopatología , Tamoxifeno/uso terapéutico , Anciano , Anciano de 80 o más Años , Aminoglutetimida/administración & dosificación , Aminoglutetimida/efectos adversos , Antineoplásicos Hormonales/administración & dosificación , Antineoplásicos Hormonales/efectos adversos , Antineoplásicos Hormonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Inhibidores de la Aromatasa/administración & dosificación , Inhibidores de la Aromatasa/efectos adversos , Índice de Masa Corporal , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/fisiopatología , Femenino , Humanos , Persona de Mediana Edad , Posmenopausia , Estudios Prospectivos , Receptores de Superficie Celular/biosíntesis , Tamoxifeno/administración & dosificación , Tamoxifeno/efectos adversos , Resultado del Tratamiento
5.
Carbohydr Polym ; 92(2): 1767-75, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-23399218

RESUMEN

PLA biocomposites were prepared using three corn cob fractions and a wood fiber as reference. The composites were characterized by tensile testing, scanning electron microscopy (SEM) and polarization optical microscopy (POM). Micromechanical deformation processes were followed by acoustic emission measurements. The different strength of the components was proved by direct measurements. Two consecutive micromechanical deformation processes were detected in composites containing the heavy fraction of corncob, which were assigned to the fracture of soft and hard particles, respectively. The fracture of soft particles does not result in the failure of the composites that is initiated either by the fracture of hard particles or by matrix cracking. Very large particles debond easily from the matrix resulting in catastrophic failure at very low stresses. At sufficiently large shear stresses large particles break easily during compounding, thus reinforcement depending on interfacial adhesion was practically the same in all composites irrespectively of initial fiber characteristics.


Asunto(s)
Ácido Láctico/química , Lignina/química , Polímeros/química , Poliésteres , Estrés Mecánico , Relación Estructura-Actividad , Resistencia a la Tracción , Madera/química
6.
Brain Res ; 1508: 9-22, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23352668

RESUMEN

Selective-breeding of house mice for increased voluntary wheel-running has resulted in multiple physiological and behavioral changes. Characterizing these differences may lead to experimental models that can elucidate factors involved in human diseases and disorders associated with physical inactivity, or potentially treated by physical activity, such as diabetes, obesity, and depression. Herein, we present ethological data for adult males from a line of mice that has been selectively bred for high levels of voluntary wheel-running and from a non-selected control line, housed with or without wheels. Additionally, we present concentrations of central monoamines in limbic, striatal, and midbrain regions. We monitored wheel-running for 8 weeks, and observed home-cage behavior during the last 5 weeks of the study. Mice from the selected line accumulated more revolutions per day than controls due to increased speed and duration of running. Selected mice exhibited more active behaviors than controls, regardless of wheel access, and exhibited less inactivity and grooming than controls. Selective-breeding also influenced the longitudinal patterns of behavior. We found statistically significant differences in monoamine concentrations and associated metabolites in brain regions that influence exercise and motivational state. These results suggest underlying neurochemical differences between selected and control lines that may influence the observed differences in behavior. Our results bolster the argument that selected mice can provide a useful model of human psychological and physiological diseases and disorders.


Asunto(s)
Conducta Animal/fisiología , Monoaminas Biogénicas/metabolismo , Química Encefálica/genética , Química Encefálica/fisiología , Carrera/fisiología , Carrera/psicología , Ácido 3,4-Dihidroxifenilacético/metabolismo , Análisis de Varianza , Animales , Peso Corporal , Cruzamiento , Dopamina/metabolismo , Ácido Hidroxiindolacético/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Motivación , Actividad Motora/genética , Actividad Motora/fisiología , Selección Genética , Serotonina/metabolismo
7.
J Appl Physiol (1985) ; 109(3): 778-85, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20558760

RESUMEN

We investigated the effects of genetic selection and prolonged wheel access (8 wk) on food consumption and body composition in lines of rats selected for high and low intrinsic (untrained) endurance running capacity (HCR and LCR, respectively) to test the generality of phenotypic correlations between physical activity levels, aerobic capacity, and body composition. HCR rats ran more minutes per day on activity wheels than LCR rats, supporting the hypothesis that voluntary activity and physiological capacity are genetically correlated (self-induced adaptive plasticity). Both treatments (selection and wheel access) significantly affected food consumption. HCR rats consumed and digested more food than LCR rats. Access to running wheels did not result in changes in overall body mass, but lean body mass increased and percent body fat decreased in both lines. Selection for high endurance capacity resulted in hypertrophy of the heart and kidneys and decreased long intestine length. We found significant phenotypic flexibility in a number of organ masses after wheel running. Specifically, access to running wheels resulted in hypertrophy of the heart, liver, kidney, stomach, and small and large intestines in LCR and HCR rats. The selected line×wheel access interaction was significantly greater in HCR rats in relative mass for the heart and lung. Compared with LCR rats, HCR rats fortify wheel running with increased food consumption along with greater hypertrophy of key organs for O2 transport.


Asunto(s)
Conducta Animal , Composición Corporal/genética , Actividad Motora/genética , Resistencia Física/genética , Animales , Cardiomegalia/genética , Cardiomegalia/patología , Ingestión de Alimentos/genética , Femenino , Genotipo , Hipertrofia , Intestinos/patología , Análisis de los Mínimos Cuadrados , Hígado/patología , Masculino , Fenotipo , Ratas , Ratas Endogámicas , Selección Genética , Estómago/patología , Factores de Tiempo , Volición
9.
Neuroscience ; 158(2): 845-55, 2009 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-19010398

RESUMEN

Stress induced by early life social isolation leads to long-lasting alterations in stress responses and serotonergic activity. Corticotropin-releasing factor (CRF) is a neurotransmitter that mediates stress responses and alters serotonergic activity. We tested the hypothesis that the stress of early life isolation enhances responses to CRF in adulthood by determining the effect of CRF infusions into the dorsal raphe nucleus (dRN) on 5-HT release in the nucleus accumbens (NAc) of adult rats using in vivo microdialysis. Juvenile male rats were either isolated or housed in groups of three for a 3-week period beginning on postnatal day 21 after which, all rats were group-reared for an additional 2 weeks. Following the isolation/re-socialization procedure, infusion of 100 ng CRF into the dRN decreased 5-HT release in the NAc of group-reared rats. This treatment did not significantly affect 5-HT release in the NAc of isolation-reared animals. In contrast, infusion of 500 ng CRF into the dRN transiently increased 5-HT release in the NAc of both group-reared and isolated animals with isolated animals showing a more prolonged serotonergic response. Western blot and immunofluorescent staining for CRF receptors in the dRN showed that CRF(2) receptor levels were increased in the dRN of isolation-reared animals when compared with group-reared rats. Taken together, the results suggest that isolation during the early part of development causes alterations in both CRF receptor levels and CRF-mediated serotonergic activity. These effects may underlie the increased sensitivity to stress observed in isolates.


Asunto(s)
Hormona Liberadora de Corticotropina/farmacología , Hormonas/farmacología , Núcleo Accumbens/efectos de los fármacos , Núcleo Accumbens/metabolismo , Aislamiento Social/psicología , Animales , Animales Recién Nacidos , Conducta Animal , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica Arqueal/efectos de los fármacos , Regulación de la Expresión Génica Arqueal/fisiología , Masculino , Microdiálisis , Ratas , Ratas Sprague-Dawley , Receptores de Hormona Liberadora de Corticotropina/metabolismo , Serotonina/metabolismo
10.
Neuroscience ; 158(2): 412-25, 2009 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-18992791

RESUMEN

Salmonids establish social hierarchies as a result of aggressive social interactions. The establishment of dominant or subordinate status is strongly linked to neuroendocrine responses mediated through the stress axis. In this study, we tested the effects of introcerebroventricular (icv) corticotropin releasing factor (CRF) on the behavioral outcome, plasma cortisol and monoamine function in trout subjected to a socially aggressive encounter. Rainbow trout were treated with an icv injection of artificial cerebrospinal fluid (aCSF), 500 or 2000 ng ovine CRF, or not injected. Fish were allowed to interact with a similarly sized conspecific for 15 min. Following the behavioral interaction, plasma cortisol and central monoamine concentrations were analyzed. Trout treated with CRF were victorious in approximately 66% of the aggressive encounters against aCSF-treated opponents. Trout injected with CRF exhibited a reduction in the total number of attacks and decreased latency to attack. When trout were divided into winners and losers, only victorious CRF-treated fish exhibited a reduced latency to attack and fewer retreats. Social stress increased cortisol levels in both winners and losers of aggressive interaction. This effect was enhanced with the additional stress incurred from icv injection of aCSF. However, icv CRF in addition to social stress decreased plasma cortisol in both winners and losers. While aggression stimulated significant changes in serotonergic and dopaminergic activity, the magnitude and direction were dependent on limbic brain region, CRF dose, and outcome of social aggression. With broad effects on aggressive behavior, anxiety, stress responsiveness, and central monoaminergic activity, CRF plays an important role in modulating the behavioral components of social interaction.


Asunto(s)
Agresión/efectos de los fármacos , Conducta Animal/efectos de los fármacos , Monoaminas Biogénicas/metabolismo , Hormona Liberadora de Corticotropina/farmacología , Reacción de Fuga/efectos de los fármacos , Análisis de Varianza , Animales , Encéfalo/anatomía & histología , Encéfalo/metabolismo , Química Encefálica/efectos de los fármacos , Hormona Liberadora de Corticotropina/metabolismo , Relación Dosis-Respuesta a Droga , Jerarquia Social , Hidrocortisona/sangre , Inyecciones Intraventriculares/métodos , Relaciones Interpersonales , Oncorhynchus mykiss , Tiempo de Reacción/efectos de los fármacos
11.
Physiol Behav ; 93(4-5): 1044-54, 2008 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-18304593

RESUMEN

A positive genetic relationship between aerobic capacity and voluntary exercise has been suggested from earlier studies of mice selected for increased wheel-running activity. To further investigate the relationship between aerobic capacity and exercise behavior, wheel-running activity was studied in female rats bidirectionally selected for intrinsic aerobic capacity (high capacity runners - HCR; low capacity runners - LCR). Aerobic capacity was measured using a forced treadmill paradigm; the subpopulations of animals used in this experiment exhibited a 471% difference in endurance capacity. Rats were housed individually, with or without access to running wheels. Wheel-running activity was recorded and analyzed from weeks two through seven during an eight-week trial to determine voluntary activity levels. HCR animals exhibited 33% greater total wheel-running distance per day compared to LCR rats (16,838.7+1337.30 m versus 12,665.8+893.88 m), which was due to the HCR rats exhibiting increases in both running speed and duration over LCR rats. Differences in the intermittency of wheel running were also observed. HCR rats engaged in more bouts of running per day than LCR rats, and trended towards running faster, for more time, and for longer distances during bouts of running than LCR rats. Following the running trial, measurement of plasma corticosterone concentration and striatal dopaminergic activity showed differences between HCR and LCR rats, suggesting a divergence of physiological systems that could potentially influence locomotor behaviors in these lines. These results are consistent with earlier work, and suggest an evolutionarily conserved relationship between physiological capacity and behavioral activity of exercise.


Asunto(s)
Monoaminas Biogénicas/metabolismo , Corticosterona/sangre , Movimiento/fisiología , Condicionamiento Físico Animal/métodos , Selección Genética , Análisis de Varianza , Animales , Conducta Animal , Índice de Masa Corporal , Ratas
12.
Neuroscience ; 141(2): 1047-1055, 2006 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-16713119

RESUMEN

The neurotransmitters serotonin and corticotrophin-releasing factor are thought to play an important role in fear and anxiety behaviors. This study aimed to determine the relationship between corticotrophin-releasing factor-evoked changes in serotonin levels within discrete regions of the limbic system and the expression of fear behavior in rats. The effects of corticotrophin-releasing factor administration to the serotonin cell body regions of the dorsal raphe nucleus on fear behavior, behavioral activity, and extracellular serotonin levels were assessed in freely moving rats with microdialysis probes implanted into the central nucleus of the amygdala and the medial prefrontal cortex. Infusion of corticotrophin-releasing factor (0.5 microg) into the dorsal raphe rapidly induced freezing behavior, which was positively correlated with an immediate increase in serotonin release in the central nucleus of the amygdala. In contrast, cessation of freezing behavior correlated with a delayed and prolonged increase in serotonin release within the medial prefrontal cortex. Our findings suggest that corticotrophin-releasing factor-induced freezing behavior is associated with regionally and temporally distinct serotonergic responses in the limbic system that may reflect differing roles for these regions in the expression of fear/anxiety behavior.


Asunto(s)
Hormona Liberadora de Corticotropina/administración & dosificación , Miedo/fisiología , Sistema Límbico/metabolismo , Núcleos del Rafe/efectos de los fármacos , Serotonina/metabolismo , Análisis de Varianza , Animales , Conducta Animal/efectos de los fármacos , Cromatografía Líquida de Alta Presión/métodos , Reacción Cataléptica de Congelación/efectos de los fármacos , Masculino , Microdiálisis/métodos , Ratas , Ratas Sprague-Dawley
13.
Aktuelle Urol ; 36(2): 136-41, 2005 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-15902574

RESUMEN

PURPOSE: Identification of prognostic factors for tumor recurrence in nephronsparing surgery and tumor progression after organ-preserving surgery. MATERIAL AND METHODS: From June 1989 to February 2003, 43 patients (47 nephron units) underwent organ-preserving surgery or the upper urinary tract because of urothelial carcinoma, with 26 (60.5 %) having an elective indication (healthy contralateral kidney). RESULTS: The mean follow-up was 39.2 months with a range of 10.6 to 168.3 months. Ipsilateral recurrences occurred in 13 (27.6 %) of reno-ureteral units. Recurrences were significantly more common for tumors located in the renal pelvis or opposite the ureteral origin (p = 0.018). Tumor progression occurred in 8 of 43 patients (18.6 %) and significantly correlated with the T- and G-stage of the primary tumor (p = 0.006 and p = 0.002). Of the 47 conservatively treated reno-ureteral units, 38 (80.8 %) could be preserved. CONCLUSION: Organ-preserving resection of the urothelial carcinoma of the upper urinary tract is an alternative in some patients with well-differentiated superficial tumors. A follow-up for life and a good patient compliance are necessary. Tumors of the renal pelvis have a significantly higher recurrence rate than ureteral tumors. Poorly differentiated tumors should undergo organ-preserving surgery only if the goal is palliation and in patients with solitary kidney after intensive consultation about the high risk of invasive recurrences and the development of metastases.


Asunto(s)
Carcinoma de Células Transicionales/cirugía , Neoplasias Renales/cirugía , Recurrencia Local de Neoplasia/etiología , Nefrectomía/métodos , Neoplasias Ureterales/cirugía , Anciano , Anciano de 80 o más Años , Carcinoma de Células Transicionales/diagnóstico por imagen , Carcinoma de Células Transicionales/patología , Femenino , Humanos , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/patología , Pelvis Renal/patología , Pelvis Renal/cirugía , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Estadificación de Neoplasias , Factores de Riesgo , Análisis de Supervivencia , Uréter/patología , Uréter/cirugía , Neoplasias Ureterales/diagnóstico por imagen , Neoplasias Ureterales/patología , Urografía
14.
Curr Mol Med ; 3(8): 707-17, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14682492

RESUMEN

Glucocorticoids (GC) control cell cycle progression and induce apoptosis in cells of the lymphoid lineage. Physiologically, these phenomena have been implicated in regulating immune functions and repertoire generation. Clinically, they form the basis of inclusion of GC in essentially all chemotherapy protocols for lymphoid malignancies. In spite of their significance, the molecular mechanisms underlying the anti-leukemic GC effects and the clinically important phenomenon of GC resistance are still unknown. This review summarizes recent findings related to GC-induced apoptosis, cell cycle arrest, and GC resistance with particular emphasis on acute lymphoblastic leukemia (ALL). We hypothesize that under conditions of physiological Bcl-2 expression, GC might induce classical programmed cell death by directly perturbing the Bcl-2 rheostat. In the presence of anti-apoptotic Bcl-2 proteins, cell death might result from accumulating catabolic and/or other detrimental GC effects driven by, and critically dependent on, GC receptor (GR) autoinduction. Although still controversial, there is increasing evidence for release of apoptogenic factors through pores in the outer mitochondrial membrane, rather than deltapsiloss-dependent membrane rupture, with maintenance of mitochondrial function at least in the early phase of the death response. GC-induced cell cycle arrest in ALL cells appears to be independent of apoptosis induction and vice versa, and critically depends on repression of both cyclin-D3 and c-myc followed by increased expression of the cyclin-dependent kinase inhibitor, p27Kip1. Since development of GC-resistant clones requires both cell cycle progression and survival, GC resistance might frequently result from structural or regulatory defects in GR expression, perhaps the most efficient means to target both pathways concurrently.


Asunto(s)
Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Resistencia a Antineoplásicos , Glucocorticoides/uso terapéutico , Leucemia Linfoide/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Humanos , Leucemia Linfoide/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo
15.
J Neuroendocrinol ; 15(12): 1122-33, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14636174

RESUMEN

Corticotropin-releasing factor (CRF) coordinates neuroendocrine responses to stressful stimuli; one mechanism through which CRF may modulate hypothalamic-pituitary-adrenal axis activity is via actions on neuromodulatory systems such as serotonergic systems. Recent electrophysiological studies and the distribution of CRF receptors within midbrain and pontine raphé nuclei suggest that stress and CRF may have actions on topographically organized subpopulations of serotonergic neurones. We compared the effects of vehicle or intracerebroventricular r/hCRF injections (0, 0.1, 1 or 10 micro g) in rats previously maintained in home cages or restrained for 1 h, 24 h before injection, on monoamine and monoamine metabolite tissue concentrations in the dorsal (lateral wings, rostral midline, caudal midline), median (rostral, caudal) and interfascicular raphé subdivisions of the midbrain and pontine raphé nuclei, using brain microdissection and high-performance liquid chromatography with electrochemical detection. At the lowest dose studied (0.1 micro g), CRF infusions in previously stressed rats decreased 5-hydroxytryptophan (5-HTP) and 5-hydroxyindoleacetic acid (5-HIAA) concentrations only within the rostral median raphé nucleus. At higher doses, CRF infusions in previously stressed rats increased tissue concentrations of 5-HTP, serotonin (5-HT), or the serotonin metabolite, 5-HIAA, within rostral (but not caudal) regions of the median and dorsal raphé nuclei. By contrast, restraint stress alone had no effect on tissue concentrations of 5-HTP, 5-HT or 5-HIAA measured 24 h later in any subdivision, while CRF injections in rats not previously exposed to restraint stress, with few exceptions, also had no effect. These results suggest that the effects of CRF on serotonergic function are context-dependent, dose-dependent, and regionally specific within subdivisions of the brainstem raphé nuclei.


Asunto(s)
Hormona Liberadora de Corticotropina/farmacología , Norepinefrina/metabolismo , Núcleos del Rafe/fisiología , Serotonina/metabolismo , Estrés Fisiológico/metabolismo , Estrés Fisiológico/fisiopatología , 5-Hidroxitriptófano/metabolismo , Animales , Ácido Hidroxiindolacético/metabolismo , Masculino , Núcleos del Rafe/anatomía & histología , Núcleos del Rafe/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Restricción Física
16.
Chirurg ; 74(6): 575-8, 2003 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-12883808

RESUMEN

INTRODUCTION: The arterial communication between the superior and inferior mesenteric arteries is important in surgery of the colon and aorta. METHODS: The anastomosis between the median colic artery (ACM) and the superior colic artery (AMS) was studied on 52 cadavers (32 female, 20 male). The length of the artery was measured using a flexible scale, and its diameter was determined at three different locations (origin, middle, end). RESULTS: The median lengths of the arteries were: 6.8 cm (range 3.9-9.7) for ACM, 12.2 cm (range 7-17.4) for ACS, and 23 cm (range 13.6-34.2) for margin artery. The median diameters were: 3.4 mm (range 2.7-4.1) for ACM, 3.1 mm (range 2.1-4.1) for ACS, and 2.7 mm (range 2-3.4) for margin artery. In 9.6% of the cadavers ( n=5), additional anastomoses between the AMS and inferior mesenteric arteries were proven. In 90.4% ( n=47), only margin arteries were found. SUMMARY: The low incidence of an additional communication (Riolan's arch) and possible additional impairment of the blood supply should be taken into account during operation.


Asunto(s)
Colon/irrigación sanguínea , Arteria Mesentérica Inferior/anatomía & histología , Arteria Mesentérica Superior/anatomía & histología , Angiografía , Circulación Colateral , Historia del Siglo XVI , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Arteria Mesentérica Inferior/cirugía , Arteria Mesentérica Superior/cirugía , Valores de Referencia
17.
Brain Behav Evol ; 57(6): 317-27, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11713386

RESUMEN

A social sign stimulus that is sympathetically induced affects aggressive approaches and influences serotonergic, dopaminergic and noradrenergic activity in the brainstem nuclei of Anolis carolinensis. Darkening of postorbital skin via sympathetic activation of adrenal catecholamines and beta(2)-adrenergic receptors provides a visual signal that forms more rapidly in dominant than subordinate males during social interactions. This signal limits aggressive interactions. Males were painted postorbitally with green or black paint and then exposed to a mirror. Aggressive approaches to the mirror were inhibited in males viewing a reflection with darkened eyespots, and increased in males viewing a reflection without eyespots (hidden). Noradrenergic turnover in the raphe and locus ceruleus were greatest in test subjects that viewed a reflection with eyespots hidden by green paint. Perception of darkened eyespots stimulated greater serotonergic turnover in raphe, locus ceruleus and substantia nigra/ventral tegmental area (SN/VTA). Dopaminergic turnover was higher in the raphe and SN/VTA of Anolis that viewed a reflection with darkened eyespots. However, these animals had lower dopamine turnover in the locus ceruleus than isolated and hidden eyespot groups. Of the possible roles of perikarya on central function and behavior, our results suggest feedback, cross-nuclear regulation, and some independence of function between nuclei and the forebrain terminal fields. Decreased serotonergic activity corresponds with increased aggression only in the raphe, suggesting that the raphe nuclei might be important for this behavioral trait. Increased serotonergic, noradrenergic and dopaminergic activities in SN/VTA in Anolis that view a reflected opponent with dark eyespots suggests that the SN/VTA might be directly involved in recognition of this social sign stimulus and the resulting inhibition of aggression.


Asunto(s)
Agresión/fisiología , Comunicación Animal , Tronco Encefálico/fisiología , Lagartos/fisiología , Neurotransmisores/fisiología , Conducta Social , Sistema Nervioso Simpático/fisiología , Conducta Agonística/fisiología , Animales , Mapeo Encefálico , Dopamina/fisiología , Masculino , Vías Nerviosas/fisiología , Norepinefrina/fisiología , Serotonina/fisiología , Pigmentación de la Piel/fisiología , Sustancia Negra/fisiología , Área Tegmental Ventral/fisiología
18.
Horm Behav ; 39(3): 195-205, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11300710

RESUMEN

Monoaminergic systems are important modulators of the neuroendocrine, autonomic, and behavioral responses to stress-related stimuli. The male roughskin newt (Taricha granulosa) was used as a model system to investigate the effects of corticotropin-releasing factor (CRF) or corticosterone administration on tissue concentrations of norepinephrine, epinephrine, dopamine, 3,4-dihydroxyphenylacetic acid, serotonin, and 5-hydroxyindoleacetic acid (5-HIAA) in microdissected brain areas. Intracerebroventricular infusion of 25 or 50 ng of CRF increased locomotor activity and site-specifically increased dopamine concentrations within the dorsomedial hypothalamus 30 min after treatment when compared to vehicle-treated controls. In further studies, male newts were treated as follows: (1) no injection, no handling, (2) saline injection, or (3) 10 microg corticosterone and then placed in a novel environment. Monoamine and monoamine metabolite concentrations were similar in the unhandled and saline-injected controls 20 min after treatment. In contrast, corticosterone-injected newts had elevated concentrations of dopamine, serotonin, and 5-HIAA in the dorsomedial hypothalamus (a region that contains dopamine- and serotonin-accumulating neuronal cell bodies in representatives of all vertebrate classes) but not in several other regions studied. These site-specific neurochemical effects parallel neurochemical changes observed in the dorsomedial hypothalamic nucleus of mammals following exposure to a variety of physical and psychological stress-related stimuli. Therefore, these changes may reflect highly conserved, site-specific neurochemical responses to stress and stress-related neurochemicals in vertebrates. Given the important role of the dorsomedial hypothalamus in neuroendocrine, autonomic, and behavioral responses to stress, and a proposed role for this region in fast-feedback effects of glucocorticoids on the hypothalamo-pituitary-adrenal axis, these stress-related monoaminergic changes are likely to have important physiological or behavioral consequences.


Asunto(s)
Antiinflamatorios/farmacología , Corticosterona/farmacología , Hormona Liberadora de Corticotropina/farmacología , Dopamina/metabolismo , Núcleo Hipotalámico Dorsomedial/metabolismo , Serotonina/metabolismo , Animales , Ansiedad/metabolismo , Núcleo Hipotalámico Dorsomedial/efectos de los fármacos , Locomoción/fisiología , Masculino , Salamandridae , Conducta Sexual Animal/fisiología , Estrés Psicológico
20.
Dig Surg ; 17(4): 413-4, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11053955

RESUMEN

BACKGROUND/AIMS: Needles are among the most frequently swallowed foreign bodies. In most cases they are excreted per vias naturales, but in some cases needles can lead to perforation of the stomach or duodenum in adults. METHODS: We report a case of acute appendicitis after perforation of the appendix by a swallowed needle. An appendectomy was performed without any knowledge of the reason for perforation. RESULTS: Inspection of the resected appendix demonstrated a needle of 1.5 cm length inside the lumen of the appendix, which had caused a perforation of the distal end of the appendix. CONCLUSION: As seen in this case a longer-lasting nondiagnosed perforation can lead to extensive local inflammation which could have been avoided by early surgical treatment which should also be considered if the patient has very few symptoms, as in this case.


Asunto(s)
Apendicitis/etiología , Apéndice/lesiones , Cuerpos Extraños/complicaciones , Perforación Intestinal/etiología , Adulto , Apendicectomía , Apendicitis/cirugía , Cuerpos Extraños/diagnóstico , Humanos , Perforación Intestinal/diagnóstico , Masculino , Agujas
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