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1.
Emerg Med J ; 20(1): 25-8, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12533362

RESUMO

OBJECTIVES: This study aimed to evaluate the usefulness of a comprehensive drug screening method as a first line diagnostic tool on clinical decision making in patients attending an emergency department for suspected drug overdose in terms of agreement between physicians on patients' disposal. METHODS: Five emergency physicians retrospectively evaluated the records of 142 adult patients, admitted to the emergency department of a community hospital for suspected drug overdose. They were asked for an expert opinion on patients' disposal at the end of the observation period, based on paired records, with/without the results of a comprehensive drug screening. RESULTS: In the absence of the drug screening, a very poor agreement (kappa statistics) was observed between physicians. When the drug screening was available, the interobserver agreement for decision on patients' disposal increased to the fair to good range (global agreement: from 0.238 (0.019) to 0.461 (0.020) (mean(SE)); p<0.001). The agreement also increased when admission to an intensive care unit, to a general ward, and discharge from hospital were separately analysed. The availability of drug screening would have saved 21.7% of hospital admissions and 53.3% of high dependency and/or intensive care unit admissions. CONCLUSION: Comprehensive drug screening adds to decision making for patients attending an emergency department for suspected drug overdose, improving agreement among physicians on patients' disposal and potentially saving hospital resources.


Assuntos
Tomada de Decisões , Overdose de Drogas/diagnóstico , Serviço Hospitalar de Emergência/estatística & dados numéricos , Detecção do Abuso de Substâncias/estatística & dados numéricos , Adulto , Overdose de Drogas/psicologia , Feminino , Hospitais Comunitários , Humanos , Masculino , Auditoria Médica , Variações Dependentes do Observador , Relações Médico-Paciente , Estudos Retrospectivos
2.
Neurosci Lett ; 336(2): 131-3, 2003 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-12499057

RESUMO

The aim of the study was to investigate whether low-frequency repetitive transcranial magnetic stimulation (rTMS) over the unaffected hemisphere can ameliorate visuospatial neglect. We treated three right brain damaged patients with left neglect. 900 pulses (1 Hz frequency) were given over left posterior parietal cortex every other day for 2 weeks. Patients performed a computerized task requiring length judgement of prebisected lines, tachistoscopically presented for 150 ms. With respect to rTMS the task was given 15 days before, at the beginning, at the end and 15 days after. At these times patients performed also line bisection and clock drawing tasks. rTMS induced a significant improvement of visuo-spatial performance that remained quite unchanged 15 days after. Patients performance at Time 3 and 4 improved also as concerns line bisection and clock drawing tasks.


Assuntos
Agnosia/reabilitação , Campos Eletromagnéticos , Lobo Parietal/efeitos da radiação , Desempenho Psicomotor/efeitos da radiação , Percepção Espacial , Percepção Visual , Idoso , Agnosia/etiologia , Isquemia Encefálica/complicações , Potencial Evocado Motor/efeitos da radiação , Humanos , Masculino , Pessoa de Meia-Idade , Lobo Parietal/fisiopatologia , Transtornos da Percepção/etiologia , Transtornos da Percepção/reabilitação , Resultado do Tratamento
3.
Acta Neurol Scand ; 105(3): 152-7, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11886356

RESUMO

OBJECTIVE: To investigate the efficacy of two different high doses of intravenous methylprednisolone (IVMP) during Multiple Sclerosis (MS) relapses. BACKGROUND: Transcranial Magnetic Stimulation (TMS) is the most sensitive neurophysiological ascertainment to quantify motor disability, to follow the recovery from an MS relapse, and to detect the response to treatment. DESIGN AND METHOD: Twenty-four clinically definite relapsing - remitting MS patients presenting a relapse were randomly assigned to a treatment for 5 days with IVMP 1 or 2 g/day. The response to treatment of each patient was evaluated through Expanded Disability Status Scale (EDSS), Medical Research Council (MRC) score, and TMS by means of motor evoked potential (MEP) parameters. RESULTS: Motor threshold (MT), central motor conduction time (CMCT) and MRC showed a higher improvement with the highest dose of IVMP. Silent period and EDSS improved with both treatments. CONCLUSION: The dose of 2 g/day of IVMP is more effective in MS relapse.


Assuntos
Metilprednisolona/farmacologia , Esclerose Múltipla/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Adulto , Relação Dose-Resposta a Droga , Potencial Evocado Motor , Feminino , Humanos , Infusões Intravenosas , Imageamento por Ressonância Magnética , Masculino , Metilprednisolona/administração & dosagem , Esclerose Múltipla/fisiopatologia , Condução Nervosa , Fármacos Neuroprotetores/administração & dosagem , Recidiva , Estimulação Magnética Transcraniana , Resultado do Tratamento
4.
Neurology ; 57(7): 1338-40, 2001 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-11591865

RESUMO

To verify the role of interhemispheric influences on manifestations of neglect, the authors investigated the effects of a transient repetitive transcranial magnetic stimulation (rTMS)-induced disruption of the unaffected hemisphere on contralesional visuospatial neglect in two left- and five right-brain-damaged patients. Parietal rTMS of the unaffected hemisphere during the execution of a computerized task of bisected line's length judgment transiently decreased the magnitude of neglect as expressed in the number of errors.


Assuntos
Lateralidade Funcional , Magnetismo , Transtornos da Percepção/fisiopatologia , Idoso , Atenção , Estimulação Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lobo Parietal/fisiopatologia , Estimulação Luminosa
5.
Exp Brain Res ; 138(4): 452-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11465743

RESUMO

We studied the changes of duration of subsequent silent periods (SPs) during repetitive magnetic stimulation (rTMS) trains of ten stimuli delivered at low (1 Hz) and high (7 Hz) frequencies. The effects at different intensities of stimulation (motor threshold, MT, 115% and 130% above the MT) were also evaluated. rTMS was performed in eight healthy subjects with a figure-of-eight coil placed over the hand motor area. The SP was recorded from abductor pollicis brevis (APB) muscle during a voluntary contraction of 30% of maximum effort. rTMS at 1-Hz frequency progressively decreased the duration of SP, whereas an alternating pattern of smaller and larger values was observed during trains at 7-Hz frequency and higher stimulus intensity. The findings show that rTMS changes the duration of cortical SPs; the effect is probably due to the modulation of intracortical inhibitory interneurons depending on the frequency and intensity of stimulation.


Assuntos
Potencial Evocado Motor/fisiologia , Córtex Motor/fisiologia , Movimento/fisiologia , Contração Muscular/fisiologia , Inibição Neural/fisiologia , Vias Neurais/fisiologia , Estimulação Magnética Transcraniana , Adulto , Estimulação Elétrica/métodos , Eletromiografia , Feminino , Reflexo H , Humanos , Masculino , Córtex Motor/anatomia & histologia , Neurônios Motores/fisiologia , Músculo Esquelético/fisiologia , Vias Neurais/anatomia & histologia , Tempo de Reação/fisiologia
6.
Neuroreport ; 11(7): 1519-21, 2000 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10841369

RESUMO

We applied repetitive transcranial magnetic stimulation (rTMS) in order to induce interference on visuo-spatial perception in 11 healthy subjects. Subjects performed a visuo-spatial task requiring judgements about the symmetry of prebisected lines. Visual stimuli consisted of symmetrically or asymmetrically transected lines, tachystoscopically presented for 50 ms on a computer-monitor. Performance was examined in basal condition and during rTMS trains of 10 stimuli at 25 Hz, delivered through a focal coil over right or left posterior parietal cortex (P5 and P6 sites) and triggered synchronously with visual stimulus. Randomly intermixed sham rTMS trains were employed to control for non-specific effects. Right parietal rTMS induced a significant rightward bias in symmetry judgements as compared with basal and sham rTMS conditions. No differences emerged between other conditions.


Assuntos
Agnosia/fisiopatologia , Lateralidade Funcional/fisiologia , Magnetismo , Lobo Parietal/fisiologia , Percepção Espacial/fisiologia , Adulto , Idoso , Estimulação Elétrica , Humanos , Pessoa de Meia-Idade , Estimulação Luminosa , Desempenho Psicomotor/fisiologia
7.
J Neurol Sci ; 174(2): 122-6, 2000 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10727697

RESUMO

The aim of the study was to assess if the observation of single or more complex muscle movements activates the premotor cortex in man. We stimulated by transcranial magnetic stimulation the right and left motor cortex recording from the abductor pollicis brevis of eight normal subjects, during observation of different movements performed by the examiner: (1) single movements: thumb abduction, arm elevation; (2) motor sequences: finger opposing movements performed in an ordinate sequence: 1-2, 1-3, 1-4, 1-5, 1-2ellipsis, and in a non-consecutive non-repetitive order: 1-3, 1-5, 1-4, 1-2, 1-5, 1-2ellipsis We found an increased excitability of the right cortex during observation of isolated muscle movement regardless of which muscle is moved. At the stimulation of the left cortex, MEPs were significantly increased during observation of complex muscular synergies.


Assuntos
Campos Eletromagnéticos , Atividade Motora/fisiologia , Córtex Motor/fisiologia , Adulto , Braço/fisiologia , Dominância Cerebral , Estimulação Elétrica , Potenciais Evocados , Feminino , Dedos/fisiologia , Humanos , Masculino , Rede Nervosa/fisiologia , Polegar/fisiologia
8.
Funct Neurol ; 14(3): 149-54, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10568215

RESUMO

Ten patients with myotonic muscular dystrophy (MD) were examined by auditory event-related potentials (P300 ERPs), spirometric and blood gas analyses: arterial oxygen tension (PaO2), arterial carbon dioxide tension (PaCO2) and arterial oxygen saturation (SaO2). The aim of the study was to analyse the frequency of ERP abnormalities in this disease and to determine whether the neurophysiological evidence of cognitive impairment might be related to the ventilatory function abnormalities frequently described in MD. The mean P300 latency was significantly altered in MD patients compared with controls; P300 latencies did not correlate with spirometric parameters, blood gas values or with age, age at onset, duration or clinical status of the disease. This study provides neurophysiological evidence of cognitive impairment in MD patients. The cognitive deficits are not related to alveolar hypoventilation and appear to be a non progressive feature of the disease.


Assuntos
Potenciais Evocados P300/fisiologia , Distrofia Miotônica/fisiopatologia , Troca Gasosa Pulmonar/fisiologia , Mecânica Respiratória/fisiologia , Espirometria , Adulto , Encéfalo/fisiopatologia , Dióxido de Carbono/sangue , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distrofia Miotônica/diagnóstico , Distrofia Miotônica/genética , Oxigênio/sangue
9.
Electromyogr Clin Neurophysiol ; 39(6): 337-44, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10499203

RESUMO

A neurophysiological (SEP, VEP) follow-up study was carried out in 30 diabetic patients with type I diabetes mellitus of ten or more years duration. This in order to investigate whether one year of improved glucoregulation may influence the progression of central damage. In our series, patients showed a significant decrement of HbA1C levels (p < 0.05) in the one-year follow-up. In the same period the frequency of SEP and VEP abnormalities varied from 10/30 (33%) to 16/30 (53%) and from 8/30 (26%) to 5/30 (16%) respectively. This finding would suggest that prevailing glycaemic control would be a major determinant for the outcome of VEP measurements. SEP alterations, in contrast, tend to progress in a 12 months period despite a considerable improvement in glycaemic control. However, by dividing patients in two groups according mean one year HbA1C less than 8% and more than 8%, the latter group only showed a significant increasing of absolute latencies of each median and tibial SEP components. Our results suggest that VEP abnormalities are still reversible in diabetic patients with improved metabolic control. The acquired abnormalities of somatosensory pathways persist longer, but a strict glycaemic control may influence and retard the progression of central conduction involvement.


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Neuropatias Diabéticas/fisiopatologia , Potenciais Somatossensoriais Evocados/fisiologia , Potenciais Evocados Visuais/fisiologia , Adolescente , Adulto , Glicemia/metabolismo , Criança , Diabetes Mellitus Tipo 1/diagnóstico , Neuropatias Diabéticas/diagnóstico , Feminino , Seguimentos , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Vias Neurais/fisiopatologia , Tempo de Reação/fisiologia , Córtex Somatossensorial/fisiopatologia , Córtex Visual/fisiopatologia
10.
Clin Neurophysiol ; 110(5): 806-12, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10400193

RESUMO

OBJECTIVE: Focal transcranial magnetic stimulation (TMS) was used to study the motor maps of upper limb muscles in 7 adult patients with a history of paralytic poliomyelitis. The aim of the study was to verify the potential for long-term cortical reorganization of a selective peripheral motor neuron lesion suffered early in life. METHODS: Patient selection was based on the prevalent involvement of proximal muscles in only one of the upper limbs. Motor evoked potentials (MEPs) were recorded from deltoid and abductor pollicis brevis (APB) muscles. Each muscle map was characterized by area (no. of excitable positions), volume (the sum of MEP amplitudes at all scalp positions), maximal amplitude (the highest MEP recorded). RESULTS: In the patients, the mean area, volume and maximal amplitude were significantly greater in affected vs. contralateral deltoid (P<0.05) and vs. controls (P<0.01). No significant differences were found in APB map parameters. The APB/deltoid ratio for area was lower in the affected compared with the unaffected side and controls (P = 0.06). Cortical reorganization was not significantly correlated with motor performance. CONCLUSION: These findings are consistent with a rearrangement in human motor pathways targeting muscles affected by a lower motor neuron lesion.


Assuntos
Córtex Motor/fisiopatologia , Poliomielite/fisiopatologia , Adulto , Mapeamento Encefálico , Eletroencefalografia , Feminino , Humanos , Magnetismo , Masculino , Pessoa de Meia-Idade
11.
Electromyogr Clin Neurophysiol ; 39(5): 305-13, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10422001

RESUMO

We performed clinical, radiological (MRI) and neurophysiological (NCV, SEPs, and BAEPs) investigations in 36 unselected patients affected by Systemic Lupus Erythematosus (SLE). Fifteen patients (42%) presented clear neurological events and were considered as definite neuropsychiatric lupus (NPLE); 21 (58%) presented minor subjective complaints or no neurological problems referable to SLE and were considered as no-NPLE. Twenty-three patients (64%) showed neurophysiological abnormalities: 21 (58%) presented central abnormal neurophysiological measurements (including SEP and BAEP values), while 17 (47%) has slowed peripheral nerve conduction. Twenty-six out of 36 patients executed brain MRI examination. High intensity spots (HIS) in deep or subcortical white matter were the most common abnormalities and were present in 19 of the 26 patients (73%). We found that the incidence of neurophysiological and radiological abnormalities did not significantly differ in neurologically symptomatic and asymptomatic patients. Central nervous system impairment evidenced by abnormal N13-20 interpeak intervals (p = 0.05) and HIS (p = 0.01) findings was significantly associated with the presence of cutaneous vasculitis; while peripheral nerve involvement was significantly more frequent in patients with renal failure (p = 0.006).


Assuntos
Potenciais Evocados/fisiologia , Lúpus Eritematoso Sistêmico/fisiopatologia , Imageamento por Ressonância Magnética , Injúria Renal Aguda/fisiopatologia , Adulto , Encefalopatias/diagnóstico , Encefalopatias/fisiopatologia , Córtex Cerebral/patologia , Distribuição de Qui-Quadrado , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Potenciais Somatossensoriais Evocados/fisiologia , Feminino , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico , Masculino , Condução Nervosa/fisiologia , Neurofisiologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Tempo de Reação , Dermatopatias Vasculares/fisiopatologia , Vasculite/fisiopatologia
12.
Electromyogr Clin Neurophysiol ; 39(3): 155-60, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10228882

RESUMO

Median and tibial somatosensory evoked potentials (SEPs) were performed on 12 patients at three and twelve weeks after a first acute stroke, the relationship with motor and functional outcome as measured by British Medical Scale and Barthel Index was searched. Results indicated that the amplitude abnormalities of cortical potentials performed about three weeks after stroke are a good indicator of a poor motor and functional impairment after three months. Moreover changes in amplitude appeared more frequent and permanent than the latency abnormalities.


Assuntos
Transtornos Cerebrovasculares/fisiopatologia , Potenciais Somatossensoriais Evocados/fisiologia , Idoso , Idoso de 80 Anos ou mais , Estimulação Elétrica , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculos/fisiopatologia , Prognóstico , Tempo de Reação/fisiologia
13.
Eur J Neurol ; 5(1): 89-94, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10210817

RESUMO

Somatosensory evoked potentials (SEPs) and brainstem auditory evoked potentials (BAEPs) were recorded in 10 patients with myotonic dystrophy and in 20 sex and age-matched healthy controls. In all patients a brain MRI examination was also performed. In our results, the significantly longer absolute peak latencies of the SEPs and the abnormal increasing of the later components of the BAEPs suggest an involvement of the afferent sensory and central auditory pathways. Brain MRI showed white matter hyperintense lesions (WMHL) in eight patients (80%). No correlations were found between individual abnormal electrophysiological parameters or severity of WMHL and age, age at onset, disease duration or muscular impairment. The total number (SEP + BAEP) of electrophysiological abnormalities significantly correlated with muscular impairment (p < 0.05) and MRI changes (p < 0.005), suggesting a strict pathogenetic linkage between muscular and nervous system alterations in this disease.

14.
Clin Ter ; 148(9): 351-92, 1997 Sep.
Artigo em Italiano | MEDLINE | ID: mdl-9410662

RESUMO

After reporting the pathophysiology of denervation the authors deal with the changes that affect nerves while going through reinnervation. A review of the drugs that may help healing and general care to be adopted in order to avoid sequential pathological phenomena related to paralysis are shown. Rehabilitative treatment is discussed, the Authors dwell upon rehabilitation of neurogenous bladder of patients with spina bifida and rehabilitation of patients with paralysis of brachial plexus. Facial paralysis has been discussed before dealing with benefits and complications of electrotherapy. The use of electromagnetotherapy and electromyography are shown with a rich photographic and bibliographic support.


Assuntos
Doenças do Sistema Nervoso Periférico/reabilitação , Plexo Braquial/fisiopatologia , Denervação , Terapia por Estimulação Elétrica/métodos , Humanos , Regeneração Nervosa , Paralisia/reabilitação , Modalidades de Fisioterapia , Disrafismo Espinal/complicações , Disrafismo Espinal/terapia , Bexiga Urinaria Neurogênica/etiologia , Bexiga Urinaria Neurogênica/reabilitação
15.
Electroencephalogr Clin Neurophysiol ; 105(4): 297-301, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9284237

RESUMO

To further define motor nervous system alterations in myotonic dystrophy (MD), motor potentials to transcranial and cervical magnetic stimulation (MEPs) were recorded from the right abductor pollicis brevis muscle in 10 patients with MD and in 10 healthy controls. Cortical and cervical latencies, central motor conduction time (CMCT), stimulus threshold intensity and cortical MEP amplitudes expressed both as absolute values and as %M were analysed. MEP cervical latency, absolute or relative amplitude and excitability threshold did not significantly differ in patients and controls. The mean cortical motor latency and CMCT were significantly prolonged in MD patients with respect to normal subjects. Moreover, CMCTs were found to be significantly related to stimulus threshold intensity (P = 0.03) and only marginally related to absolute cortical amplitude (P = 0.06). These findings are indicative of a central motor delay, also related to decreased excitability of motor neurons, in patients with MD. No correlations were found between individual neurophysiological parameters and age, duration of disease and clinical impairment. Our results suggest that magnetic stimulation studies can detect subclinical dysfunctions of the central motor system in MD patients, as one of the multisystemic manifestations of the disease, rather independent of the primitive muscle damage.


Assuntos
Potencial Evocado Motor/fisiologia , Magnetismo , Distrofia Miotônica/fisiopatologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Clin Ter ; 148(7-8): 313-48, 1997.
Artigo em Italiano | MEDLINE | ID: mdl-9377865

RESUMO

The correct treatment of patients with cerebrovascular accident should be established after understanding the phenomena that affect the cerebral tissue from the beginning of the stroke up to its healing. The cerebral edema pathophysiology, the role played by glutamate and calcium in the brain toxicity, and by neurotrophic factors and neuroplasticity in recovery, are treated. Moreover, changes in mood after a stroke, are related to the side of the lesion. A comment on the different techniques of rehabilitation as part of treatment of patient with brain injury, is given.


Assuntos
Transtornos Cerebrovasculares/reabilitação , Neurobiologia , Atividades Cotidianas , Transtornos Cerebrovasculares/fisiopatologia , Transtornos Cerebrovasculares/psicologia , Terapia Cognitivo-Comportamental , Humanos , Estilo de Vida , Modalidades de Fisioterapia , Resultado do Tratamento
18.
Acta Neurol Scand ; 95(6): 346-50, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9228268

RESUMO

Nerve conduction velocities (NCVs), somatosensory (SEPs) and auditory evoked potentials (BAEPs) were recorded in 9 patients with facio-scapulo-humeral dystrophy (FSHD) and in 20 age-matched controls. In FSHD patients a significant increase of the nerve distal sensory latencies and of the absolute SEP latencies revealed a subclinical involvement of the afferent sensory pathways, as well as the abnormal slowing of the later components of the BAEPs, pointed to a central auditory dysfunction. Moreover all patients underwent brain MRI that showed the presence of white matter hyperintense lesions in 4 of them (44%). No correlations were found between individual or total number of SEP and BAEP abnormal electrophysiological parameters and severity of WMHL, age, age at onset, duration of the disease or muscular impairment. These findings make the interpretation and pathophysiology of the nervous damage in FSHD rather uncertain. More studies are required to better define the aspects of neurogenic involvement in this type of muscular dystrophy.


Assuntos
Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Potenciais Somatossensoriais Evocados/fisiologia , Distrofias Musculares/fisiopatologia , Condução Nervosa/fisiologia , Adulto , Braço , Doenças Auditivas Centrais/etiologia , Doenças Auditivas Centrais/fisiopatologia , Encéfalo/patologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Face , Feminino , Variação Genética/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Nervo Mediano/fisiopatologia , Pessoa de Meia-Idade , Distrofias Musculares/complicações , Índice de Gravidade de Doença , Ombro , Nervo Tibial/fisiopatologia
19.
Hepatology ; 8(5): 1079-83, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3417228

RESUMO

The galactose elimination capacity, a measure of the functional liver cell mass, and liver volume were measured in 50 normal subjects of five different age groups (less than 50, 51 to 60, 61 to 70, 71 to 80 and greater than 81 years). The volume of the liver was evaluated by ultrasonography. All subjects had normal routine liver function tests and no history of liver disease. Galactose elimination progressively decreased from 3.05 +/- 0.58 (S.D.) mmoles per min in younger subjects to 1.83 +/- 0.24 mmoles per min in subjects over 81 (p less than 0.00003), without any change in the apparent volume of distribution of the sugar. Similarly, the estimated volume of the liver decreased from 110 +/- 14 units to 75 +/- 13 units with increasing age (p less than 0.0002). Both galactose elimination capacity and the estimated liver volume inversely correlated with age (r = -0.728 and r = -0.579, respectively) whereas a positive correlation was observed between galactose elimination and the estimated liver volume (r = 0.520). Part correlation analysis confirmed that age, when entered in a multiple regression already containing body weight and estimated liver volume as independent variables, had a significant effect on liver function, whereas no significant independent effect of liver volume was present. Both age and body weight had a significant independent effect on the estimated liver volume. The maximum functional capacity of the liver, measured by galactose elimination, is reduced in the elderly. Although several factors may play a role, our data suggest that aging is associated with a slight decline in the intrinsic metabolic activity of the hepatic parenchyma.


Assuntos
Envelhecimento/metabolismo , Galactose/farmacocinética , Fígado/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Peso Corporal , Jejum , Humanos , Fígado/anatomia & histologia , Pessoa de Meia-Idade , Tamanho do Órgão , Estudos Prospectivos , Valores de Referência , Fatores de Tempo
20.
Metabolism ; 36(11): 1096-100, 1987 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3312939

RESUMO

The effects of glucose-induced hyperinsulinemia on plasma amino acid levels were measured in 50 subjects divided into five age groups. Following an oral glucose load the plasma levels of most amino acids decreased, the decline being more pronounced for the three branched-chain amino acids (valine, isoleucine, and leucine). A progressive insulin resistance was proved on the basis of an age-related impaired glucose tolerance and a normal or increased insulin response. The plasma disappearance of branched-chain amino acids significantly correlated with age (r = -.514). The effects of the prevailing plasma insulin on branched-chain amino acids, measured by the ratio of amino acid changes per total insulin response, progressively declined in older subjects (P = .0005), and strictly correlated with age (r = .652). Insulin resistance in the elderly similarly affects glucose and branched-chain amino acid metabolism, with possible relevant effects on whole-body protein turnover.


Assuntos
Idoso de 80 Anos ou mais , Idoso , Aminoácidos de Cadeia Ramificada/sangue , Glicemia/análise , Resistência à Insulina , Insulina/sangue , Envelhecimento , Aminoácidos/sangue , Glucose/administração & dosagem , Humanos , Pessoa de Meia-Idade
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