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1.
Gynecol Oncol ; 143(2): 398-405, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27538367

RESUMEN

BACKGROUND: Forkhead box protein A2 (FOXA2) plays an important in development, cellular metabolism and tumorigenesis. The Cancer Genome Atlas (TCGA) identified a modest frequency of FOXA2 mutations in endometrioid endometrial cancers (EEC). The current study sought to determine the relationship between FOXA2 mutation and clinicopathologic features in EEC and FOXA2 expression. METHODS: Polymerase chain reaction (PCR) amplification and sequencing were used to identify mutations in 542 EEC. Western blot, quantitative reverse transcriptase PCR (qRT-PCR) and immunohistochemistry (IHC) were used to assess expression. Methylation analysis was performed using combined bisulfite restriction analysis (COBRA) and sequencing. Chi-squared, Fisher's exact, Student's t- and log-rank tests were performed. RESULTS: Fifty-one mutations were identified in 49 tumors (9.4% mutation rate). The majority of mutations were novel, loss of function (LOF) (78.4%) mutations, and most disrupted the DNA-binding domain (58.8%). Six recurrent mutations were identified. Only two tumors had two mutations and there was no evidence for FOXA2 allelic loss. Mutation status was associated with tumor grade and not associated with survival outcomes. Methylation of the FOXA2 promoter region was highly variable. Most tumors expressed FOXA2 at both the mRNA and protein level. In those tumors with mutations, the majority of cases expressed both alleles. CONCLUSION: FOXA2 is frequently mutated in EEC. The pattern of FOXA2 mutations and expression in tumors suggests complex regulation and a haploinsufficient or dominant-negative tumor suppressor function. In vitro studies may shed light on how mutations in FOXA2 affect FOXA2 pioneer and/or transcription factor functions in EEC.


Asunto(s)
Carcinoma Endometrioide/patología , Neoplasias Endometriales/genética , Genes Supresores de Tumor , Factor Nuclear 3-beta del Hepatocito/genética , Mutación , Anciano , Endometrio/metabolismo , Femenino , Humanos , Persona de Mediana Edad
2.
Biochem Pharmacol ; 190: 114653, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34129858

RESUMEN

The discovery of the chemical synapse was a seminal finding in Neurobiology but the large body of microscopic interactions involved in synaptic transmission could hardly have been foreseen at the time of these first discoveries. Characterization of the molecular players at work at synapses and the increased granularity at which we can now analyze electrical and chemical signal processing that occur in even the simplest neuronal system are shining a new light on receptor interactions. The aim of this review is to discuss the complexity of some representative interactions between excitatory and inhibitory ligand-gated ion channels and/or G protein coupled receptors, as well as other key machinery that can impact neurotransmission and to explain how such mechanisms can be an important determinant of nervous system function.


Asunto(s)
Canales Iónicos Activados por Ligandos/metabolismo , Red Nerviosa/fisiología , Receptores Acoplados a Proteínas G/metabolismo , Animales , Regulación de la Expresión Génica , Humanos , Canales Iónicos Activados por Ligandos/genética , Receptores Acoplados a Proteínas G/genética
3.
Am J Transplant ; 10(5): 1312-5, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20353461

RESUMEN

BK virus (BKV) has emerged as a major complication of kidney transplantation. Since June 30, 2004, the OPTN in the USA collects BKV as a primary or secondary cause of graft loss and also if treatment for BK virus (TBKV) is administered. In this study, we determined characteristics of those recipients of repeat kidney transplants from the OPTN database, where either (a) a graft loss occurred between June 30, 2004 and December 31, 2008 and database recorded prior TBKV in that allograft or (b) a graft loss between June 30, 2004 and December 31, 2008 was attributed primarily or secondarily due to BKV. In the study time period, 823 graft losses have occurred where TBKV or graft failure attributable to BKV was reported in prior transplant; of these, 126 have received a retransplant as of June 5, 2009. Induction and maintenance immunosuppression usage mirrored current trends. As of June 5, 2009, 118/126 grafts are still functioning, one graft failure attributed to BKV. TBKV was reported in 17.5% of the retransplants. In the retransplants performed through December 31, 2007, 1-year acute rejection rate was 7%, 1-year and 3-year Kaplan-Meier graft survival rates and median GFR were 98.5%, 93.6%, 65.5 and 68.4 mL/min, respectively. Retransplantation after BKV appears to be associated with good results.


Asunto(s)
Virus BK , Enfermedades Renales/virología , Trasplante de Riñón , Técnicas de Laboratorio Clínico , Bases de Datos Factuales , Tasa de Filtración Glomerular , Rechazo de Injerto/virología , Humanos , Terapia de Inmunosupresión , Riñón/virología , Investigación , Tasa de Supervivencia , Estados Unidos
4.
Neurobiol Stress ; 13: 100262, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33344715

RESUMEN

Acute physical or psychological stress can elicit adaptive behaviors that allow an organism maintain homeostasis. However, intense and/or prolonged stressors often have the opposite effect, resulting in maladaptive behaviors and curbing goal-directed action; in the extreme, this may contribute to the development of psychiatric conditions like generalized anxiety disorder, major depressive disorder, or post-traumatic stress disorder. While treatment of these disorders generally focuses on reducing reactivity to potentially threatening stimuli, there are in fact impairments across multiple domains including valence, arousal, and cognition. Here, we use the genetically stress-susceptible 129S1 mouse strain to explore the effects of stress across multiple domains. We find that 129S1 mice exhibit a potentiated neuroendocrine response across many environments and paradigms, and that this is associated with reduced exploration, neophobia, decreased novelty- and reward-seeking, and spatial learning and memory impairments. Taken together, our results suggest that the 129S1 strain may provide a useful model for elucidating mechanisms underlying myriad aspects of stress-linked psychiatric disorders as well as potential treatments that may ameliorate symptoms.

5.
Clin Nephrol ; 72(3): 186-92, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19761723

RESUMEN

BACKGROUND: Leptospirosis is an infrequent disease in the US, with most cases reported in the state of Hawaii. Renal involvement is common (44 - 67%), ranging from a mild prerenal azotemia in anicteric disease to renal failure requiring dialysis in Weil's syndrome (severe leptospirosis with jaundice, renal failure, and hemorrhage). METHODS: To describe the pattern of leptospiral renal disease at our institution, we performed a retrospective analysis (1992 - 2004) of all hospitalized cases of laboratory confirmed leptospirosis presenting with acute kidney injury (AKI), defined as a presenting serum creatinine > 1.5 mg/dl. RESULTS: During this time period, 18 patients were hospitalized with laboratory confirmed leptospirosis. Among these patients, 12 had AKI on presentation, and hemodialysis was required in 3 patients. Renal biopsies were performed in 2 of these patients, revealing acute tubulointerstitial nephritis. Interestingly, the patients who required dialysis did not have Weil's syndrome. They did not exhibit jaundice or hemorrhage, and serum AST (mean 51.7 U/l (range 36 - 60)), ALT (mean 51.0 U/l (range 38 - 64)), and total bilirubin (mean 1.2 mg/dl (range 0.8 - 1.8)) were either within normal limits or only slightly elevated, despite having the worst renal disease. CONCLUSIONS: This series adds to other evidence that severe AKI (requiring dialysis) can complicate anicteric leptospirosis in contrast to the notion that the AKI in anicteric disease is typically mild and prerenal. Leptospirosis should be considered in all patients who present with fever and AKI, especially if associated with thrombocytopenia or travel to an endemic area.


Asunto(s)
Lesión Renal Aguda/etiología , Lesión Renal Aguda/terapia , Leptospirosis/complicaciones , Diálisis Renal , Adulto , Femenino , Humanos , Masculino , Estudios Retrospectivos
6.
Sci Rep ; 7: 39662, 2017 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-28045073

RESUMEN

Pain places a devastating burden on patients and society and current pain therapeutics exhibit limitations in efficacy, unwanted side effects and the potential for drug abuse and diversion. Although genetic evidence has clearly demonstrated that the voltage-gated sodium channel, Nav1.7, is critical to pain sensation in mammals, pharmacological inhibitors of Nav1.7 have not yet fully recapitulated the dramatic analgesia observed in Nav1.7-null subjects. Using the tarantula venom-peptide ProTX-II as a scaffold, we engineered a library of over 1500 venom-derived peptides and identified JNJ63955918 as a potent, highly selective, closed-state Nav1.7 blocking peptide. Here we show that JNJ63955918 induces a pharmacological insensitivity to pain that closely recapitulates key features of the Nav1.7-null phenotype seen in mice and humans. Our findings demonstrate that a high degree of selectivity, coupled with a closed-state dependent mechanism of action is required for strong efficacy and indicate that peptides such as JNJ63955918 and other suitably optimized Nav1.7 inhibitors may represent viable non-opioid alternatives for the pharmacological treatment of severe pain.


Asunto(s)
Canal de Sodio Activado por Voltaje NAV1.7/metabolismo , Dolor/metabolismo , Venenos de Araña/farmacología , Bloqueadores del Canal de Sodio Activado por Voltaje/farmacología , Animales , Línea Celular , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Humanos , Masculino , Dolor/prevención & control , Ratas Sprague-Dawley , Venenos de Araña/química , Bloqueadores del Canal de Sodio Activado por Voltaje/química
7.
Neuroscience ; 133(4): 1073-9, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15964492

RESUMEN

The most ubiquitous form of arrhythmia is respiratory sinus arrhythmia in which the heart beat slows during expiration and heart rate increases during inspiration. Whereas respiratory sinus arrhythmia benefits pulmonary gas exchange respiratory dysfunction presents a major challenge to the cardiorespiratory system. Hypoxia evokes a pronounced bradycardia mediated by increases in parasympathetic cardiac activity. It has been hypothesized that the fatal events in sudden infant death syndrome (SIDS) are exaggerated cardiorespiratory responses to hypoxia. This study tests whether premotor cardiac vagal neurons receive rhythmic respiratory-related excitatory synaptic inputs during normoxia and hypoxia, and if animals exposed to nicotine in the prenatal period have exaggerated responses to hypoxia. Premotor cardiac vagal neurons in the nucleus ambiguus were identified in rats by the presence of a fluorescent tracer in medullary slices that generate rhythmic inspiratory-related motor discharge. Respiratory activity was recorded from the hypoglossal nerve and excitatory synaptic events in cardiac vagal neurons were isolated using patch clamp techniques. Adult female rats were implanted with osmotic minipumps that delivered nicotine at a level approximately equivalent to those that occur in moderate to heavy smokers. During normal eupneic respiration, as well as during hypoxia, premotor cardiac vagal neurons from control animals did not receive any rhythmic respiratory-related excitatory inputs. However in animals exposed to nicotine throughout the prenatal period respiratory bursts during hypoxia dramatically increased the frequency of excitatory synaptic events in cardiac vagal neurons. In summary, in animals exposed to nicotine throughout the prenatal period, but not in unexposed animals, respiratory bursts that occur during hypoxia dramatically increase the frequency of excitatory synaptic events in cardiac vagal neurons. This study establishes a likely neurochemical mechanism for the heart rate responses to hypoxia and a link between prenatal nicotine exposure and exaggerated bradycardia responses during hypoxia that may contribute to sudden infant death syndrome.


Asunto(s)
Tronco Encefálico/citología , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Hipoxia/fisiopatología , Neuronas/efectos de los fármacos , Nicotina/farmacología , Agonistas Nicotínicos/farmacología , 6-Ciano 7-nitroquinoxalina 2,3-diona/farmacología , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Animales , Animales Recién Nacidos , Tronco Encefálico/efectos de los fármacos , Tronco Encefálico/fisiopatología , Interacciones Farmacológicas , Antagonistas de Aminoácidos Excitadores/farmacología , Potenciales Postsinápticos Excitadores/fisiología , Antagonistas del GABA/farmacología , Glicinérgicos/farmacología , Vías Nerviosas/efectos de los fármacos , Vías Nerviosas/fisiología , Neuronas/fisiología , Picrotoxina/farmacología , Ratas , Ratas Sprague-Dawley , Respiración/efectos de los fármacos , Estricnina/farmacología , Valina/análogos & derivados , Valina/farmacología
8.
Arch Gen Psychiatry ; 41(10): 990-7, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6332592

RESUMEN

Information about point prevalence of depression and anxiety disorders from two cross-sectional surveys in Stirling County (Canada) indicates that an overall prevalence rate of 12.5% characterized a year close to midcentury and a prevalence rate of 12.7% characterized another year toward the end of the century's third quarter. The stability of the prevalence rates contrasts sharply with the fact that numerous social changes took place over this period of time in this place of study. There were, however, small trends in the distribution of depression and anxiety by sex and age, especially an increased similarity in the overall rates for men and women in the age range of 40 to 69 years. Hypotheses are offered about social circumstances that may have influenced the diminishing difference between the sexes.


Asunto(s)
Trastornos de Ansiedad/epidemiología , Trastorno Depresivo/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Trastornos de Ansiedad/diagnóstico , Estudios Transversales , Recolección de Datos/métodos , Recolección de Datos/normas , Trastorno Depresivo/diagnóstico , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Factores Sexuales , Estadística como Asunto
9.
Pediatrics ; 69(3): 301-4, 1982 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7199705

RESUMEN

The association between bronchopulmonary dysplasia and sudden infant death syndrome was studied retrospectively in low-birth-weight infants discharged from the neonatal program at Harvard Medical School. The incidence of sudden infant death syndrome was seven times greater in infants with bronchopulmonary dysplasia when compared with a group of control infants without bronchopulmonary dysplasia. Confounding factors, including birth weight, sex, multiple birth, socioeconomic status, and apnea were evaluated. The results indicate that there is an association between bronchopulmonary dysplasia and sudden infant death syndrome.


Asunto(s)
Displasia Broncopulmonar/complicaciones , Muerte Súbita del Lactante/etiología , Apnea/complicaciones , Femenino , Edad Gestacional , Humanos , Lactante , Recién Nacido de Bajo Peso , Recién Nacido , Masculino , Embarazo , Embarazo Múltiple , Estudios Retrospectivos , Factores Socioeconómicos
10.
Pediatrics ; 63(1): 64-72, 1979 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-375171

RESUMEN

A prospective double-blind randomized clinical trial was carried out to determine whether glucocorticoid treatment reduces the risk of respiratory distress syndrome (RDS) in prematurely born infants. There were 127 infants born to 122 mothers who received either steroid (dexamethasone phosphate) or placebo. No differences between groups occurred in risk factors for RDS (eg, prepartum asphyxia, male sex, cesarean section). When those who received a full course of dexamethasone therapy were compared with those who received placebo, a significant reduction was found in risk, severity, and deaths due to RDS. An increased incidence of infection in mothers treated with steroid was evident, particularly after premature rupture of membranes. We conclude that steroids are effective in reducing risk of RDS, but safer and more efficacious approaches for the prevention of RDS should be sought.


Asunto(s)
Dexametasona/uso terapéutico , Síndrome de Dificultad Respiratoria del Recién Nacido/prevención & control , Ensayos Clínicos como Asunto , Método Doble Ciego , Femenino , Humanos , Recién Nacido , Masculino , Placebos , Embarazo , Estudios Prospectivos
11.
J Nucl Med ; 19(5): 553-6, 1978 May.
Artículo en Inglés | MEDLINE | ID: mdl-641580

RESUMEN

Although Co-57 is generally used for testing the field uniformity of scintillation cameras, the various photon energies of other radionuclides require uniform response throughout the entire range of energies to which a scintillation camera can respond. The use of Co-57, however, may not adequately demonstrate the field response, which may be uniform at 122 keV but not at other energies. Two scintillation camera systems were investigated in this regard by storing field-flood images, obtained at several photon energies, in a minicomputer. The stored data were analyzed using the Kolmogorov-Smirnov test, revealing that field uniformity may change with photon energy. One of the scintillation cameras showed a variation in field response with photon energy, whereas the other camera did not. These results, however, should not be extrapolated to other cameras of the same type. If a particular scintillation camera is to be used routinely with several energies, its performance should be tested with each one to provide assurance that valid information is being obtained. The effects of dynamic uniformity field correction remain to be evaluated.


Asunto(s)
Cintigrafía/instrumentación , Control de Calidad
12.
Proc Biol Sci ; 268(1473): 1307-13, 2001 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-11410159

RESUMEN

The influence of noise is unavoidable in all living systems. Its impact on a model of a biological clock, normally running in regular oscillating modes, is examined. It is shown that in a specific system in which endogenous rhythmicity is produced by a beat oscillator acting on a feedback coupled metabolic pool system, noise can act coherently to produce unexpected dynamic behaviour, running from regular over pseudo-regular to irregular time-structures. If the biological system consists of a set of identical weakly coupled cells, stochasticity may lead to phase decoupling producing irregular spatio-temporal patterns. Synchronization via phase resetting can be achieved by external short-time temperature pulses. Explicit results are obtained for the well-studied circadian photosynthesis oscillations in plants performing crassulacean acid metabolism. Because of the generic structure of the underlying nonlinear dynamics they can, however, be regarded as a general property of the influence of noise on nonlinear excitable systems with fixed points occuring close to limit cycles.


Asunto(s)
Relojes Biológicos , Modelos Biológicos , Ritmo Circadiano , Magnoliopsida/metabolismo , Dinámicas no Lineales , Fotosíntesis , Procesos Estocásticos
13.
Chest ; 97(5): 1266-7, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2331933

RESUMEN

Women in the Collaborative Perinatal Project who received theophylline during pregnancy were no more likely to be delivered of a stillborn infant than were women who did not receive theophylline. These findings add to the safety record associated with maternal receipt of theophylline during pregnancy.


Asunto(s)
Asma/tratamiento farmacológico , Muerte Fetal/inducido químicamente , Complicaciones del Embarazo/tratamiento farmacológico , Teofilina/toxicidad , Estudios de Cohortes , Femenino , Muerte Fetal/epidemiología , Humanos , Embarazo , Estudios Prospectivos , Factores de Riesgo , Teofilina/uso terapéutico , Estados Unidos
14.
Ann N Y Acad Sci ; 940: 237-46, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11458681

RESUMEN

Cardiac vagal neurons play a critical role in the control of heart rate and cardiac function. These neurons, which are primarily located in the nucleus ambiguus (NA) and the dorsal motor nucleus of the vagus (DMNX), dominate the neural control of heart rate under normal conditions. Cardiac vagal activity is diminished and unresponsive in many disease states, while restoration of parasympathetic activity to the heart lessens ischemia and arrhythmias and decreases the risk of sudden death. Recent work has demonstrated that cardiac vagal neurons are intrinsically silent and therefore rely on synaptic input to control their firing. To date, three major synaptic inputs to cardiac vagal neurons have been identified. Stimulation of the nucleus tractus solitarius evokes a glutamatergic pathway that activates both NMDA and non-NMDA glutamatergic postsynaptic currents in cardiac vagal neurons. Acetylcholine excites cardiac vagal neurons via three mechanisms, activating a direct ligand-gated postsynaptic nicotinic receptor, enhancing postsynaptic non-NMDA currents, and presynaptically by facilitating transmitter release. This enhancement by nicotine is dependent upon activation of pre- and postsynaptic P-type voltage-gated calcium channels. Additionally, there is a GABAergic innervation of cardiac vagal neurons. The transsynaptic pseudorabies virus that expresses GFP (PRV-GFP) has been used to identify, for subsequent electrophysiologic study, neurons that project to cardiac vagal neurons. Bartha PRV-GFP-labeled neurons retain their normal electrophysiological properties, and the labeled baroreflex pathways that control heart rate are unaltered by the virus.


Asunto(s)
Tronco Encefálico/fisiología , Corazón/inervación , Neuronas/fisiología , Neurotransmisores/fisiología , Sinapsis/fisiología , Nervio Vago/fisiología , Animales , Ácido Glutámico/fisiología , Humanos , Receptores Nicotínicos/fisiología , Nervio Vago/citología , Ácido gamma-Aminobutírico/fisiología
15.
Obstet Gynecol ; 55(1): 60-6, 1980 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6153240

RESUMEN

The maternal serum alpha-fetoprotein (AFP) in 6161 women in routine pregnancy [2771 in a hospital obstetric clinic (group 1) and 3390 in private practices (group 2)] was studied. Group 1 studies enabled the delineation of the normal range of serum AFP, whereas group 2 represented a true screening experience. In group 2, 39 (2.5%) of 1566 women at 16 to 18 weeks' gestation had raised (2.5 times the median or more) serum AFP. Of these 39 women, 3 (7.8%) had neural tube defects (NTDs), 6 (15.4%) had multiple pregnancies, 1 (2.6%) had congenital nephrosis, 7 (17.9%) had spontaneous abortions, 7 (17.9%) had miscellaneous associated factors, and 15 (38.5%) had raised serum AFP for no obvious reason. Only 16 (1%) women had "unnecessary" amniocenteses. None of these aborted subsequently. Analysis of the combined data showed that NTDs were detectable in 87.5% of patients-all 6 with anencephaly and 1 of 2 with spina bifida (1 spina bifida lesion closed); multiple pregnancy was determined in 45% (18/40 cases), and spontaneous abortion ensued in 14.5%. In group 1 a raised serum AFP was associated with a host of complications in 77.3% of the women. Low AFP values had associated complications in 72.2% of cases. Maternal serum AFP screening represents another potentially important tool for early detection of high-risk pregnancy.


Asunto(s)
Defectos del Tubo Neural/diagnóstico , Diagnóstico Prenatal , alfa-Fetoproteínas/análisis , Amniocentesis , Femenino , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Embarazo , Estudios Prospectivos
16.
Brain Res ; 739(1-2): 258-62, 1996 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-8955946

RESUMEN

Heart rate is normally dominated by the activity of the cardioinhibitory parasympathetic nervous system, while abnormally low levels of parasympathetic cardiac activity have been implicated in many cardiovascular diseases including hypertension, heart failure and sudden cardiac death. In this study we have examined the voltage-gated currents in parasympathetic cardiac neurons that were identified with a retrograde fluorescent tracer in visualized sections (250 microns) of nucleus ambiguus. Depolarization of parasympathetic cardiac neurons to potentials more positive than -50 mV evoked a rapidly activating and inactivating inward current which could be blocked by tetrodotoxin (TTX), although in some neurons up to 10 microM was required for complete block. The voltage-dependent inactivation properties of this Na current showed relatively broad inactivation characteristics, a characteristic of TTX-resistant Na channels. Depolarization also elicited biphasic outward currents, which were separated into a transient IA type K current using the specific channel antagonist 4-aminopyridine and a long-lasting delayed rectified K current. These voltage-gated Na and K currents define the action potential firing patterns of parasympathetic cardiac neurons, such as frequency adaptation and spike delay, and also determine the activity of these neurons in response to depolarizing and hyperpolarizing synaptic innervation.


Asunto(s)
Corazón/inervación , Bulbo Raquídeo/fisiología , Neuronas/fisiología , Sistema Nervioso Parasimpático/fisiología , Canales de Potasio/fisiología , Canales de Sodio/fisiología , 4-Aminopiridina/farmacología , Animales , Fibras Autónomas Preganglionares/citología , Fibras Autónomas Preganglionares/efectos de los fármacos , Fibras Autónomas Preganglionares/fisiología , Potenciales Evocados/efectos de los fármacos , Potenciales Evocados/fisiología , Activación del Canal Iónico , Bulbo Raquídeo/citología , Bulbo Raquídeo/efectos de los fármacos , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Inhibición Neural/efectos de los fármacos , Inhibición Neural/fisiología , Neuronas/efectos de los fármacos , Sistema Nervioso Parasimpático/efectos de los fármacos , Canales de Potasio/efectos de los fármacos , Ratas , Canales de Sodio/efectos de los fármacos , Transmisión Sináptica/efectos de los fármacos , Transmisión Sináptica/fisiología , Tetrodotoxina/farmacología
17.
Brain Res ; 792(2): 277-82, 1998 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-9593939

RESUMEN

While it is widely accepted that tonic and reflex changes in cardiac vagal activity play significant roles in cardiovascular function, little is known about the synaptic pathways in the brainstem responsible for the control of cardiac vagal neurons in the nucleus ambiguus (NA). In this study, we identified the principal post-synaptic receptors activated in cardiac vagal neurons upon stimulation of the nucleus tractus solitarius (NTS). Cardiac vagal neurons were identified by the presence of a retrograde fluorescent tracer and were visualized in rat brainstem slices. Perforated patch clamp techniques were used to record post-synaptic currents. NTS stimulation activated glutamatergic currents in cardiac vagal neurons with a typical delay of 8-18 ms. Post-synaptic responses were separated into NMDA and non-NMDA components using D-2-amino-5-phophonovalerate (AP5) and 6-cyano-7-nitroquinoxaline-2, 3-dione (CNQX), respectively. In conclusion, this study characterizes a monosynaptic glutamatergic pathway from NTS that activates NMDA and kainate/AMPA post-synaptic receptors in cardiac vagal neurons.


Asunto(s)
Corazón/inervación , Receptores de N-Metil-D-Aspartato/fisiología , Núcleo Solitario/fisiología , Nervio Vago/química , Nervio Vago/fisiología , 2-Amino-5-fosfonovalerato/farmacología , 6-Ciano 7-nitroquinoxalina 2,3-diona/farmacología , Animales , Antagonistas de Aminoácidos Excitadores/farmacología , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Potenciales Postsinápticos Excitadores/fisiología , Neuronas/efectos de los fármacos , Neuronas/fisiología , Técnicas de Cultivo de Órganos , Sistema Nervioso Parasimpático/química , Sistema Nervioso Parasimpático/citología , Sistema Nervioso Parasimpático/fisiología , Ratas , Núcleo Solitario/citología , Nervio Vago/citología
18.
Pancreas ; 1(3): 224-31, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3575307

RESUMEN

The effect of feeding four synthetic retinoids was evaluated in carcinogen-treated hamsters. Syrian golden hamsters were injected with 20 mg/kg of N-nitrosobis(2-oxopropyl)amine (BOP) and then fed retinoid-supplemented diets for 39 weeks. All retinoid-treated groups grew more slowly than controls, and average survival was shorter in female retinoid-treated groups. A significant incidence of testicular atrophy was noted in male hamsters fed 2-hydroxyethylretinamide or 4-carboxyphenylretinamide. The incidence of pancreatic carcinomas was lower in 12 of 14 retinoid-fed groups than in the corresponding control groups, although the differences approached significance only in groups fed two of the retinoids--male hamsters fed N-4-propionyloxyphenylretinamide and those fed retinylidene dimedone. A low incidence of carcinoma in the control groups limits the conclusions that can be drawn from this study, but it is of note that there was no evidence of promotion.


Asunto(s)
Neoplasias Pancreáticas/tratamiento farmacológico , Retinoides/uso terapéutico , Adenocarcinoma/patología , Animales , Atrofia/inducido químicamente , Carcinógenos , Carcinoma in Situ/patología , Cricetinae , Modelos Animales de Enfermedad , Femenino , Hiperplasia/patología , Masculino , Mesocricetus , Nitrosaminas , Neoplasias Pancreáticas/inducido químicamente , Neoplasias Pancreáticas/patología , Factores Sexuales , Testículo/patología
19.
Neurosci Lett ; 195(3): 163-6, 1995 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-8584200

RESUMEN

This study examines the effect of acetylcholine (Ach) on parasympathetic vagal neurons in the dorsal motor nucleus of the vagus (DMNX). Patch-clamp techniques were utilized to examine voltage and ligand-gated currents in visualized DMNX neurons in an in vitro slice. Ach (100 microM) activated an inward current, -196.4 +/- 56.9 pA at -80 mV (n = 15) that was accompanied by a decrease in membrane resistance of 48.6 +/- 9.2% in a population of DMNX neurons. The reversal potential for this ligand-gated current was -11.3 +/- 11.5 mV. The specific agonist nicotine (200 microM) elicited similar responses. Nicotine decreased membrane resistance by 60.9 +/- 4.3% and activated an inward current (-215.7 +/- 45.7 pA at -80 mV) that reversed at -12.7 +/- 20.4 mV (n = 16). Bethanecol (100 microM), a specific muscarinic agonist, had no effect. Neither Ach or nicotine had any effect on the voltage-gated sodium and outward potassium currents present in these neurons.


Asunto(s)
Acetilcolina/fisiología , Neuronas Motoras/fisiología , Receptores Nicotínicos/fisiología , Nervio Vago/fisiología , Animales , Betanecol/farmacología , Potenciales de la Membrana/fisiología , Neuronas Motoras/ultraestructura , Agonistas Muscarínicos/farmacología , Nicotina/farmacología , Agonistas Nicotínicos/farmacología , Técnicas de Placa-Clamp , Canales de Potasio/fisiología , Ratas , Ratas Sprague-Dawley , Nervio Vago/citología
20.
Am J Surg ; 149(5): 623-6, 1985 May.
Artículo en Inglés | MEDLINE | ID: mdl-3887956

RESUMEN

We have evaluated our experience with computerized tomography and ultrasonography guided percutaneous drainage of extrahepatic abdominal fluid collections in a group of 22 patients. The most common goal was to avoid or delay surgery on abdomens in which reoperation would be difficult, mainly in high-risk patients. Drainage of pancreatic fluid collections or abscesses was also attempted in a small number of the patients. Percutaneous drainage was curative in 69 percent of those with nonpancreatic abscesses but in only 33 percent of those with abscesses associated with the pancreas. There were no complications attributable to the procedure or to delays in subsequent surgical drainage. Two patients died from problems not directly related to the use of percutaneous drainage. Percutaneous catheter drainage of nonpancreatic abdominal abscesses can play a useful role in patients who are carefully selected because they possess a complex abdominal anatomy distorted by previous surgery and infection or they are at high risk if surgical exploration is carried out.


Asunto(s)
Abdomen/cirugía , Absceso/terapia , Drenaje/métodos , Absceso/diagnóstico por imagen , Absceso/etiología , Drenaje/efectos adversos , Humanos , Enfermedades Pancreáticas/complicaciones , Cuidados Posoperatorios , Complicaciones Posoperatorias , Tomografía Computarizada por Rayos X , Ultrasonografía
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