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1.
Int J Environ Health Res ; 32(5): 1164-1174, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-33249915

RESUMEN

This study is part of the health surveillance system set up with the construction of a waste-to-energy (WTE) plant in Turin (Italy). Circulatory and respiratory diseases in emergency room (ER) accesses and first hospital admissions were considered. Main concerns of population living in the area near WTE were to know whether single and repeated peaks in emissions would correspond to adverse health effects. We tackle this issue using spatio-temporal analyses, comparing an exposed group (EXP) living near the WTE with a reference group (NOEXP). Age-standardized rates of ER accesses between EXP and NOEXP were temporally compared, testing whether there have been significantly different changes over time. We also examined the relationship between emission peaks and ER accesses in the following days. Finally, with time-series analysis, we investigated variations in ER accesses and pollutants before and after WTE start-up. No significant relationship has been found for the outcome considered.


Asunto(s)
Contaminantes Ambientales , Incineración , Servicio de Urgencia en Hospital , Hospitales , Italia
2.
Environ Int ; 121(Pt 2): 1087-1097, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30366659

RESUMEN

BACKGROUND: The LIFE MED HISS project aims at setting up a surveillance system on the long term effects of air pollution on health, using data from National Health Interview Surveys and other currently available sources of information in most European countries. Few studies assessed the long term effect of air pollution on hospital admissions in European cohorts. OBJECTIVE: The objective of this paper is to estimate the long term effect of fine particulate matter (PM2.5) and nitrogen dioxide (NO2) on first-ever (incident) cause-specific hospitalizations in Italy. METHODS: We used data from the Italian Longitudinal Study (ILS), a cohort study based on the 1999-2000 National Health Interview Survey (NHIS), followed up for hospitalization (2001-2008) at individual level. The survey contains information on crucial potential confounders: occupational/educational/marital status, body mass index (BMI), smoking habit and physical activity. Annual mean exposure to PM2.5 and NO2 was assigned starting from simulated gridded data at spatial resolution of 4 × 4 km2 firstly integrated with data from monitoring stations and then up-scaled at municipality level. Statistical analyses were conducted using Cox proportional hazard models with robust variance estimator. RESULTS: For each cause of hospitalization we estimated the hazard ratios (HRs) adjusted for confounders with 95% Confidence Interval (CI) related to a 10 µg/m3 increase in pollutants. For PM2.5 and NO2, respectively, we found positive associations for circulatory system diseases [1.05(1.03-1.06); 1.05(1.03-1.07)], myocardial infarction [1.15(1.12-1.18); 1.15(1.12-1.18)], lung cancer [1.18(1.10-1.26); 1.20(1.12-1.28)], kidney cancer [1.24(1.11-1.29); 1.20(1.07-1.33)], all cancers (but lung) [1.06(1.04-1.08); 1.06(1.04-1.08)] and Low Respiratory Tract Infections (LRTI) [1.07 (1.04-1.11); 1.05 (1.02-1.08)]. DISCUSSION: Our results add new evidence on the effects of air pollution on first-ever (incident) hospitalizations, both in urban and rural areas. We demonstrated the feasibility of a low-cost monitoring system based on available data.


Asunto(s)
Contaminación del Aire/análisis , Hospitalización/estadística & datos numéricos , Exposición por Inhalación/estadística & datos numéricos , Humanos , Italia/epidemiología , Estudios Longitudinales
3.
Transplant Proc ; 40(10): 3437-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19100407

RESUMEN

Mast cells (MC) are involved in the pathogenesis of interstitial fibrosis, acute renal transplant rejection, and chronic allograft nephropathy. The aim of this study was to evaluate MC tryptase concentrations in the sera of 58 renal transplant recipients at various times after surgery in relation to graft function. We observed that kidney transplantation patients showed much higher serum tryptase concentrations than healthy controls. We demonstrated a positive correlation between serum tryptase concentration and hemoglobin, hematocrit, red blood cell count, and hepatic cell damage. We were not able to show any direct correlation between serum tryptase concentration and graft function. The clinical relevance of these findings demand further investigation.


Asunto(s)
Trasplante de Riñón/patología , Trasplante de Riñón/fisiología , Triptasas/sangre , Adulto , Anciano , Alanina Transaminasa/sangre , Biomarcadores/metabolismo , Ciclosporina/sangre , Ciclosporina/uso terapéutico , Recuento de Eritrocitos , Femenino , Hematócrito , Hemoglobinas/metabolismo , Humanos , Inmunosupresores/sangre , Inmunosupresores/uso terapéutico , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/enzimología , Valores de Referencia , Adulto Joven
4.
Klin Oczna ; 101(4): 261-6, 1999.
Artículo en Polaco | MEDLINE | ID: mdl-10581892

RESUMEN

The authors present the modified associated technique of deep sclerectomy ab externo with implant. The indications, advantages and disadvantages are presented.


Asunto(s)
Glaucoma de Ángulo Abierto/cirugía , Esclerótica/cirugía , Trabeculectomía/métodos , Humanos
5.
Thyroid ; 9(3): 289-95, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10211607

RESUMEN

Autoantibodies reacting with extracellular matrix proteins have been extensively studied in various autoimmune connective tissue diseases. Because of the possibility that such antibodies may play a role in orbital connective tissue inflammation in thyroid-associated ophthalmopathy (TAO), we studied the humoral immune response against specific extracellular matrix (ECM) proteins, namely: collagen types I, III, IV, V (CI, CIII, CIV, CV), fibronectin (FN), and laminin (LM). Anti-ECM antibodies of immunoglobulin G (IgG), IgA, and IgM classes were determined by enzyme linked immunosorbent assay (ELISA). Overall, sera from 50% of patients with TAO contained antibodies reactive against one or more ECM proteins, compared to 27% with Graves' disease (GD) without evident eye involvement, 28% with Hashimoto's thyroiditis (HT), and 9% of normal subjects. Serum anti-CI, anti-CIII, anti-CV and anti-LM levels were significantly (p<0.05) higher in patients with TAO than in normals. Anti-CI, anti-CV and anti-LM reactivity was antigen-specific in most TAO sera, while anti-CIII antibodies cross-reacted with other antigens. Anti-collagen antibodies were mainly of the IgG class. To determine the structural epitopes of these proteins, we performed immunoblotting studies on cyanogenbromide (CNBr)-derived peptides of CI and CV. While sera from 9 of 10 patients with TAO reacted with CI peptides, the response was polyclonal and uniform in all patients. However, only 2 of 10 TAO sera reacted with CV peptides. In conclusion, our study suggests that a variety of ECM proteins (CI, CV, LM) may be secondary autoantigens that are recognized by antibodies in TAO. While these antibodies appear to react with epitopes expressed on both native and denatured proteins, and may therefore have the potential to bind to ECM in vivo, their pathogenic role in TAO remains unknown.


Asunto(s)
Autoanticuerpos/sangre , Proteínas de la Matriz Extracelular/inmunología , Enfermedad de Graves/inmunología , Adolescente , Adulto , Anciano , Especificidad de Anticuerpos , Colágeno/inmunología , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Femenino , Enfermedad de Graves/sangre , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Laminina/inmunología , Masculino , Persona de Mediana Edad , Desnaturalización Proteica/inmunología
6.
Clin Transplant ; 10(1 Pt 1): 63-6, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8652901

RESUMEN

We have recently shown that ketanserin, an antagonist of peripheral serotonin 5-HT2 receptors lowers blood erythropoietin (Epo) levels in some chronic hemodialysis patients. Based on this finding, a preliminary study was undertaken to investigate the effect of a 3-week oral ketanserin administration on serum Epo concentration and relevant hematological parameters in 4 renal allograft recipients with posttransplant erythrocytosis (PTE). We found a marked decrease in Epo concentrations following ketanserin administration, from 48% to 76% of the abnormally elevated pretreatment values with subsequent increases at 3 weeks after discontinuation of the drug in all patients studied. In 3 of them a corresponding decrease or no rise in the erythrocyte count were noted. During the 6-week study period, the need for monthly phlebotomies was eliminated in these patients. It is hypothesized that ketanserin diminishes erythropoietin synthesis and may become a new drug in the treatment of posttransplant erythrocytosis.


Asunto(s)
Eritropoyetina/sangre , Ketanserina/uso terapéutico , Trasplante de Riñón , Policitemia/tratamiento farmacológico , Antagonistas de la Serotonina/uso terapéutico , Adulto , Humanos , Ketanserina/administración & dosificación , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Antagonistas de la Serotonina/administración & dosificación , Trasplante Homólogo
7.
Przegl Lek ; 51(2): 77-81, 1994.
Artículo en Polaco | MEDLINE | ID: mdl-8058973

RESUMEN

Thromboembolic complication are often seen in patients with nephrotic syndrome (NS). A comprehensive study of haemostasis and fibrinolysis has been performed in a group of 39 patients with nephrotic syndrome. We have found increased level of fibrinogen, fibronectin, fibrin monomers, alfa 2 macroglobulin, protein C and C 1 esterase inhibitor, whereas level of alfa 2 antiplasmin, alfa 1 antitrypsin were decreased. Patients with thromboembolic complications had particularly low levels of antithrombin III and histidine rich glycoprotein.


Asunto(s)
Proteínas Sanguíneas/análisis , Hemostasis/fisiología , Síndrome Nefrótico/sangre , Tromboembolia/sangre , Adulto , Femenino , Fibrinólisis/fisiología , Humanos , Masculino , Persona de Mediana Edad , Síndrome Nefrótico/complicaciones , Tromboembolia/etiología
8.
Brain Res Bull ; 24(6): 819-25, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2372699

RESUMEN

The distribution of potentials evoked in and around forelimb MsI by graded electrical stimulation of forelimb nerves has been studied in the raccoon (Procyon lotor). These data have been correlated with cytoarchitectonic characteristics of pericruciate cortical tissue. Potentials evoked by cutaneous nerve stimulation were widely distributed in MsI and SmI, but were smaller in amplitude and of longer latency in MsI than in SmI. Stimulation of ulnar, median or deep radial nerve at 1-1.4T, a strength considered to activate only Group I muscle afferent fibers, caused evoked potentials in a localized region mostly confined to posterior sigmoid gyrus. On the basis of cytoarchitectonic features it is concluded that: a) Anterior sigmoid gyrus, to near the level of the tip of the cruciate sulcus, is area 6 cortex; b) The lateral portion of the posterior sigmoid gyrus, cortex comprising the caudal bank of the cruciate sulcus and cortex surrounding the lateral tip of the cruciate sulcus is area 4 cortex; c) The middle portion of the posterior sigmoid gyrus, almost to the lip of the cruciate sulcus rostrally and extending onto the rostral bank of the ascending coronal and postcruciate sulci caudally, is area 3a cortex. The cortical focus for Group I afferent-evoked potentials coincides with area 3a cortex. It is concluded that forelimb MsI of raccoon is organized in a fashion similar to MsI of cats and monkeys.


Asunto(s)
Miembro Anterior/inervación , Corteza Motora/fisiología , Nervios Periféricos/fisiología , Mapaches/fisiología , Corteza Somatosensorial/fisiología , Animales , Mapeo Encefálico , Estimulación Eléctrica , Potenciales Evocados , Femenino , Masculino , Neuronas Motoras/fisiología , Neuronas Aferentes/fisiología
9.
Brain Res Bull ; 24(6): 827-32, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2372700

RESUMEN

Somatosensory input to 431 neurons in MsI has been studied in unanesthetized, paralyzed raccoons (Procyon lotor). The type of sensory input to neurons in lateral sigmoid gyrus (cytoarchitectonic area 4) and in posterior sigmoid gyrus (areas 4 and 3a) was not significantly different. Of these neurons, 36% were activated by superficial cutaneous stimulation (touch, tap or hair deflection) and 26% by deep stimulation (pressure or joint movement). Mute neurons (not driven by any form of peripheral stimulation tested, or vaguely driven) comprised 38% of the sample. Only 4% of anterior sigmoid gyrus (area 6) neurons responded to superficial or deep stimulation; 96% were mute. The majority of MsI neurons had small (less than or equal to 20 cm2) peripheral receptive fields (PRFs). There was a statistically significant trend for PRF size to decrease along the proximal-distal axis of the forelimb. The area of MsI digit PRFs was significantly larger than the area of SmI digit PRFs. Comparing the data for raccoon MsI with information from the literature for cats and monkeys suggests that the type and amount of somesthetic afferent input to forelimb MsI is related to the behavioral uses to which each animal puts the forelimb.


Asunto(s)
Miembro Anterior/inervación , Mecanorreceptores/fisiología , Nervios Periféricos/fisiología , Mapaches/fisiología , Corteza Somatosensorial/fisiología , Tacto/fisiología , Vías Aferentes/fisiología , Animales , Estimulación Eléctrica , Potenciales Evocados Somatosensoriales , Femenino , Masculino , Neuronas Aferentes/fisiología
10.
Brain Res Bull ; 24(6): 833-7, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2372701

RESUMEN

Motor outflow from forelimb motorsensory cortex (MsI) to forelimb muscle motoneurons in raccoon has been investigated using three approaches: 1) determination of latencies for cortically evoked efferent discharge in forelimb nerves; 2) determination of latencies for cortical facilitation of forelimb monosynaptic reflexes; and 3) intracellular recording of cortically evoked synaptic potentials. All three approaches indicated a major polysynaptic pathway (minimally disynaptic) for corticofugal facilitation or inhibition of cervical motoneurons. Suggestive evidence for a monosynaptic connection between forelimb MsI and cervical motoneurons was found for only one motoneurons. Nevertheless, the motor pathway between MsI and cervical motoneurons was shown to be more efficacious (defined on the basis of central delays) than in the cat under similar experimental conditions. The results are discussed in terms of organization changes in forelimb MsI which appear to be related to the extent to which certain mammals use their forelimbs for manipulating and exploring objects.


Asunto(s)
Miembro Anterior/inervación , Corteza Motora/fisiología , Neuronas Motoras/fisiología , Músculos/inervación , Mapaches/fisiología , Corteza Somatosensorial/fisiología , Potenciales de Acción , Animales , Mapeo Encefálico , Vías Eferentes/fisiología , Humanos , Lactante , Masculino , Tiempo de Reacción
11.
J Neurophysiol ; 61(6): 1131-41, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2746314

RESUMEN

1. The presence and pattern of resting discharge were examined in 100 single neurons of the raccoon main cuneate nucleus (MCN). Of these, 66 were activated, either antidromically or synaptically, by electrical stimulation of the contralateral thalamic ventrobasal complex (VB), and 34 were activated by stimulation of the ipsilateral cerebellum (CB). 2. Forty-one percent of VB-activated neurons displayed a resting discharge, whereas 32% of CB-activated neurons did. Most neurons activated from VB and showing a resting discharge fired in bursts of 2-5 spikes, whereas those activated from CB and showing a resting discharge generally fired as single, irregularly spaced spikes, with occasional bursts in some neurons. 3. All neurons antidromically activated from VB were histologically localized within the clusters region of the MCN, whereas those antidromically activated from CB were confined to its polymorphic region. Neurons synaptically activated from either VB or CB were located in either of these regions. 4. Differences in the proportions of neurons displaying a resting discharge did not vary significantly as a function of type of preparation: methoxyflurane anesthesia, pentobarbital sodium anesthesia, decerebrate (the latter CB-activated only). 5. Although the sample sizes were too small to demonstrate statistical significance, neurons exhibiting a resting discharge were more likely to show a bursting pattern in methoxyflurane-anesthetized preparations than were neurons in pentobarbital sodium-anesthetized preparations. 6. The probability of having no resting discharge, firing in bursts, or firing in single spikes was not related to cutaneous submodality [rapidly adapting (RA), slowly adapting (SA), Pacinian (Pc)], or to receptive field (RF) locus (glabrous versus hairy skin). 7. The overall mean rate of firing (11.8 Hz) was not significantly different for bursting versus nonbursting neurons. 8. In bursting neurons, median interspike intervals (ISIs) varied between 1.3 and 2.3 ms. Most bursting neurons also had a range of short or minimal interburst intervals (MIBIs), characteristic for each neuron, whose medians varied from neuron to neuron between 34 and 90 ms. Distributions of within-burst ISIs and MIBIs had comparable coefficients of variation, varying between 0.031 and 0.223. 9. The application of a mechanical stimulus to a neuron's peripheral RF led to a decrease in interburst intervals, accompanied, depending upon the unit, by either an increase or a decrease in the number of spikes per burst. 10. Results are discussed in terms of the functional significance of resting discharge, including bursting, and possible roles in somatosensory information


Asunto(s)
Bulbo Raquídeo/fisiología , Neuronas/fisiología , Animales , Cerebelo/fisiología , Estimulación Eléctrica , Femenino , Masculino , Potenciales de la Membrana , Mapaches , Tálamo/fisiología
12.
Am J Sports Med ; 16(1): 64-9, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3344883

RESUMEN

Twenty-two male and female college varsity tennis players trained for 6 weeks, one group using eccentric isokinetic internal and external shoulder rotation, and the second group using concentric isokinetic internal and external shoulder rotation. Subjects pretested and posttested both concentrically and eccentrically, so that training overflow and specificity could be examined. Three maximally hit tennis serves made before and after training, which were analyzed by high speed cinematography to obtain ball velocity, served as a functional performance measurement. Statistical analysis of peak torque (newton meters) and peak torque to body weight ratio have revealed significant concentric strength gains (P less than 0.005) in the concentric as well as the eccentric training groups. Eccentric strength gains were demonstrated by the concentric training group at selected speeds (P less than 0.05 and P less than 0.005) but were not generated in the eccentric group at the P less than 0.05 significance level. Functional test analysis shows an increase in maximal serve velocity at a significance level of P less than 0.005 in the concentric training group, with no significant (P greater than 0.01) increases in the eccentric group.


Asunto(s)
Contracción Isométrica , Contracción Muscular , Educación y Entrenamiento Físico/métodos , Hombro , Deportes , Tenis , Femenino , Humanos , Masculino , Películas Cinematográficas , Distribución Aleatoria , Rotación , Articulación del Hombro/fisiología , Estadística como Asunto , Resistencia a la Tracción
15.
Artículo en Inglés | MEDLINE | ID: mdl-2436997

RESUMEN

1-deamino-8-D-arginine vasopressin (DDAVP) was administered intranasally in a dose of 2 micrograms/kg BW to 17 uremic patients (16 maintained on chronic hemodialysis and 1 treated conservatively). The bleeding time was significantly shortened 120 minutes after DDAVP administration (from 18.1 +/- 7.5 minutes to 12.3 +/- 6.4 minutes p less than 0.001). Factor VIII related antigen (VIII: Ag) did not change. Factor VIII ristocetin cofactor activity (VIII: RCof) significantly increased (from 251.2 +/- 162.0 to 336.5 +/- 167.2 p less than 0.025). Platelet count decreased significantly after DDAVP (from 174.9 +/- 43.8 X 10(9)/l to 155.6 +/- 45.9 X 10(9)/l 30 minutes p less than 0.01 and 129.8 +/- 45.2 X 10(9)/l p less than 0.005 120 minutes after DDAVP). Antithrombin III concentration, and hematocrit did not change. Our data indicate that further clinical studies of intranasal DDAVP in uremic patients during episodes of bleeding are warranted.


Asunto(s)
Tiempo de Sangría , Desamino Arginina Vasopresina/administración & dosificación , Pruebas de Función Plaquetaria , Uremia/fisiopatología , Administración Intranasal , Adulto , Enfermedad Crónica , Factor VIII/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Uremia/sangre , Uremia/tratamiento farmacológico
16.
Somatosens Res ; 2(3): 263-80, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-4001677

RESUMEN

Microelectrodes were used to record the extracellular activity of 80 single neurons of the main cuneate nucleus (MCN) of raccoons anesthetized with either methoxyflurane or pentobarbital sodium. All 80 MCN neurons had peripheral receptive fields (RFs) that lay entirely on the glabrous surfaces of the forepaw and were responsive to light mechanical stimulation. Neurons were characterized according to the nature of their response to mechanical stimulation of their RFs, as well as to their response to electrical stimulation of the contralateral thalamic ventrobasal complex (VB). All antidromically activated neurons (64% of sample) were histologically verified as falling within the clusters region of the MCN, while synaptically activated neurons (19% of sample), as well as neurons not responsive to VB stimulation (17% of sample), were located in both the clusters and the polymorphic regions. Antidromically activated neurons typically responded with a single fixed-latency spike, although a few responded with a burst of 3 or more spikes. Others responded with a single antidromic spike followed by a train of synaptically activated spikes. In these latter neurons, it was often possible to block the synaptic spikes selectively. MCN neurons were classed according to their response to controlled mechanical stimuli as rapidly adapting (RA), slowly adapting (SA), or Pacinian (Pc). The proportions of neurons falling into these categories did not vary significantly with the type of response to thalamic stimulation, and the overall percentages were 56% RA, 24% SA, and 20% Pc. These figures are very similar to those previously obtained in a sample of primary afferent fibers of the raccoon cervical cuneate fasciculus (L. M. Pubols and Pubols, 1973). Absolute displacement, displacement velocity, and force thresholds, which ranged between 4 and 326 micron, 0.01 and 16.3 micron/msec, and 120 and 3600 mg, respectively, are comparable to those previously found for primary afferents supplying mechanoreceptors of the glabrous surfaces of the raccoon's forepaw. Neither displacement nor force thresholds differed for RA versus SA neurons; however, displacement velocity thresholds were significantly lower for SA than for RA neurons.


Asunto(s)
Bulbo Raquídeo/fisiología , Mapaches/fisiología , Piel/inervación , Núcleos Talámicos/fisiología , Vías Aferentes/fisiología , Animales , Fenómenos Biomecánicos , Cerebelo/fisiología , Potenciales Evocados , Femenino , Pie/inervación , Miembro Anterior , Masculino , Estimulación Física , Umbral Sensorial
17.
Brain Res ; 323(1): 164-7, 1984 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-6525506

RESUMEN

The present study demonstrates that fibers originating in the raccoon main cuneate nucleus are not segregated in specific cortical regions of target cerebellar folia as reported in studies of the cat cuneocerebellar tract. This observation supports the hypothesis that exteroceptive and proprioceptive divisions of the raccoon cuneocerebellar tract do not exist as distinct structural entities. The findings of this study do not preclude the possibility that projections from the external and main cuneate nuclei are segregated within the cerebellar cortex on the basis of functional modality rather than nucleus of origin.


Asunto(s)
Cerebelo/anatomía & histología , Bulbo Raquídeo/anatomía & histología , Mapaches/anatomía & histología , Animales , Vías Nerviosas/anatomía & histología
18.
Somatosens Res ; 1(3): 247-64, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6494666

RESUMEN

Electrophysiological experiments were undertaken in order to locate and functionally characterize cells of the raccoon main cuneate nucleus (MCN) that can be activated by electrical stimulation of the cerebellum. A total of 98 such units were studied in pentobarbital sodium-anesthetized, methoxyflurane-anesthetized, or decerebrate preparations. Aside from a greater likelihood of resting discharge in the decerebrate preparations, no appreciable variability in physiological properties of the neurons could be attributed to differences in the type of preparation. Using constant latency of response and ability to be blocked by collision as principal criteria, both antidromically (n = 31) and synaptically (n = 67) activated neurons of the main cuneate nucleus could be identified. A small number of MCN neurons could be activated by both cerebellar and thalamic stimulation, but no unit was antidromically activated from both locations. MCN neurons projecting to the cerebellum are located primarily in the ventral polymorphic cell region of the nucleus at and rostral to the obex, corresponding to the "medial tongue" region of Johnson et al. (1968). In contrast, neurons synaptically activated from the cerebellum are found throughout the dorsoventral extent of the rostral MCN, including the "clusters" region. The majority of antidromically activated units responded to mechanical stimulation of deeper tissues, and most of these were activated by muscle stretch. Only a small portion (13-15%) of either antidromically or synaptically activated units were classed as light touch units with peripheral receptive fields (RFs) restricted to glabrous surfaces of the forepaw. Glabrous skin RFs located on the digital surfaces are smaller than those located on the palm pads. In both cases, RFs are larger than those associated with primary afferent fibers, but toward the low end of the distribution for MCN neurons not activated by cerebellar stimulation. All MCN units activated by cerebellar stimulation, regardless of modality, respond to mechanical stimulation with trains of irregularly spaced single spikes. Glabrous skin cutaneous mechanoreceptive MCN neurons, whether rapidly or slowly adapting, respond to ramp indentations with an instantaneous frequency which may be described as a power function of ramp velocity, with exponents less than one. These values are in the same range as those previously reported for primary afferents of the cuneate fasciculus (Pubols and Pubols, 1973).


Asunto(s)
Cerebelo/fisiología , Bulbo Raquídeo/fisiología , Neuronas Aferentes/fisiología , Mapaches/fisiología , Adaptación Fisiológica , Animales , Estimulación Eléctrica , Potenciales Evocados Somatosensoriales , Estimulación Física , Sinapsis/fisiología , Tálamo/fisiología
19.
J Comp Neurol ; 211(4): 363-76, 1982 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-7174899

RESUMEN

Neurons of the raccoon main (MCN) and external (ECN) cuneate nuclei having terminal fields in the anterior lobe and paramedian lobule of the cerebellum were studied by means of the retrograde transport of horseradish peroxidase (HRP). In the MCN, neurons of the polymorphic regions, but not of the round cell clusters, were labeled following HRP injections of the anterior lobe. HRP-labeled fusiform, triangular, and stellate cells were observed from 3-4 mm caudal to the obex to 2-3 mm rostral to it. The main body of labeled MCN neurons was located in the 1.25 mm immediately rostral to the obex, there forming a recognizable subnucleus in the ventral MCN. The ECN displayed uniform labelling from the anterior lobe with no particular cell type or nuclear region being labeled preferentially. A minor projection to the anterior lobe appeared to originate in the contralateral MCN and ECN. Injections of the paramedian lobule produced MCN labeling similar to that observed after anterior lobe injections, but the majority of labeled ECN neurons were found in the dorsomedial part of the nucleus. In lobule V of the anterior lobe, sagittal zone c contained the greatest density of cuneocerebellar terminals as judged by the degree of retrograde labeling seen in neurons of both the MCN and ECN. This observation was consistent with evoked potentials recorded in the anterior lobe of the raccoon cerebellum. The position of cuneocerebellar neurons in the ventrolateral MCN suggests that the bulk of the information being transferred to the cerebellum by the raccoon MCN is related to deep, rather than cutaneous, modalities.


Asunto(s)
Cerebelo/anatomía & histología , Bulbo Raquídeo/anatomía & histología , Mapaches/anatomía & histología , Animales , Mapeo Encefálico , Corteza Cerebelosa/anatomía & histología , Potenciales Evocados , Miembro Anterior/inervación , Vías Nerviosas/anatomía & histología
20.
Brain Res ; 211(2): 463-7, 1981 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-7237136

RESUMEN

There is a significant positive correlation between peripheral receptive field (RF) area and neuron locus within the rostrocaudal extent of the raccoon cuneate nucleus for units having tactile RFs on the glabrous surfaces of the forepaw digits, larger RFs being associated with more rostrally located neurons, smaller ones with caudally situated neurons, but not for units having tactile RFs on the glabrous surfaces of the palm. For digits and palm, RF areas of neurons of the cuneate nucleus are approximately 40 and 100 times larger, respectively, than RF areas of primary afferent fibers of the cuneate fasciculus.


Asunto(s)
Bulbo Raquídeo/fisiología , Neuronas/fisiología , Tacto , Animales , Miembro Anterior/inervación , Humanos , Mapaches , Piel/inervación
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