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1.
Oncogene ; 30(14): 1664-80, 2011 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-21472018

RESUMO

Wilms' tumor (WT), the most frequent renal solid tumor in children, has been linked to aberrant Wnt signaling. Herein, we demonstrate that different WTs can be grouped according to either sensitivity or resistance to an antibody (Ab) specific to frizzled7 (FZD7), a Wnt receptor. In the FZD7-sensitive WT phenotype, the Ab induced cell death of the FZD7(+) fraction, which in turn depleted primary WT cultures of their clonogenic and sphere-forming cells and decreased in vivo proliferation and survival on xenografting to the chick chorio-allantoic-membrane. In contrast, FZD7-resistant WT in which no cell death was induced showed a different intra-cellular route of the Ab-FZD7 complex compared with sensitive tumors and accumulation of ß-catenin. This coincided with a low sFRP1 and DKK1 (Wnt inhibitors) expression pattern, restored epigenetically with de-methylating agents, and lack of ß-catenin or WTX mutations. The addition of exogenous DKK1 and sFRP1 to the tumor cells enabled the sensitization of FZD7-resistant WT to the FZD7 Ab. Finally, although extremely difficult to achieve because of dynamic cellular localization of FZD7, sorting of FZD7(+) cells from resistant WT, showed them to be highly clonogenic/proliferative, overexpressing WT 'stemness' genes, emphasizing the importance of targeting this fraction. FZD7 Ab therapy alone or in combination with Wnt pathway antagonists may have a significant role in the treatment of WT via targeting of a tumor progenitor population.


Assuntos
Antineoplásicos/farmacologia , Receptores Frizzled/imunologia , Neoplasias Renais/tratamento farmacológico , Receptores Acoplados a Proteínas G/imunologia , Tumor de Wilms/tratamento farmacológico , Proteínas Wnt/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Anticorpos Monoclonais/farmacologia , Antineoplásicos/imunologia , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/farmacologia , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Neoplasias Renais/genética , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Mutação , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Serina-Treonina Quinases/farmacologia , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor/genética , Tumor de Wilms/genética , Tumor de Wilms/imunologia , Tumor de Wilms/patologia , beta Catenina/biossíntese , beta Catenina/genética
2.
Anaesthesiol Reanim ; 15(1): 43-54, 1990.
Artigo em Alemão | MEDLINE | ID: mdl-2182041

RESUMO

Following a short review of the history of regional anaesthesia in children the anatomical and physiological differences to the adult are discussed. The procedure used for instituting a regional block in combination with light general anaesthesia is described. Basically all blocks used in the adult can be performed in children as well. However, it is necessary to consider the anatomical situation in the child as well as the appropriate dosages. With the aid of an electric nerve stimulator it is possible to perform peripheral nerve blocks without the need for child cooperation. The continuous caudal technique in which catheters can be advanced to upper thoracic levels in neonates and young infants, in contrast to adults, is discussed in detail.


Assuntos
Anestesia por Condução/métodos , Adolescente , Anestesia por Condução/instrumentação , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido
3.
Anaesthesiol Reanim ; 14(5): 285-9, 1989.
Artigo em Alemão | MEDLINE | ID: mdl-2684203

RESUMO

Based on early references a survey on old local anaesthetic drugs and their present position is given: procaine, chloroprocaine, tetracaine, amylocaine, stovaine and dibucaine. Furthermore, the historical development of various local anaesthetic methods as well as their influence by modern technical advances and by modern local anaesthetic drugs is pointed out. Finally an outlook on the present position of regional anaesthetic procedures in newborns, infants and children is given.


Assuntos
Anestesia Local/história , Anestésicos Locais/história , Europa (Continente) , História do Século XIX , História do Século XX , Humanos
4.
Langenbecks Arch Chir ; 345: 499-503, 1977 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-593006

RESUMO

There have been no new developments concerning field blocks. The need for limiting the dosage of local anesthetic agents is stressed. Two methods for perivascular block are described and the use of CO2 containing local anesthetic solutions is discussed as well as the employment of peripheral nerve stimulators.


Assuntos
Bloqueio Nervoso/métodos , Nervos Periféricos/efeitos dos fármacos , Bupivacaína/farmacologia , Dióxido de Carbono/farmacologia , Etidocaína/farmacologia , Humanos , Lidocaína/farmacologia , Mepivacaína/farmacologia
5.
Am J Nephrol ; 9(1): 25-9, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2785761

RESUMO

The notion that parathyroid hormone (PTH) can serve as an immunomodulator was examined. T cell function tests were performed in 3 patients with primary hyperparathyroidism before and 1 month after parathyroidectomy (PTX). Three normal volunteers, age and sex matched, were used as controls. One patient with lipoma of the neck was also examined before and after surgical removal of the lesion. In the primary hyperparathyroidism patients the total T cells were lower, the suppressors were higher and the helper to suppressor ratio was significantly lower than in control subjects. The lectin-stimulated lymphocyte transformation was significantly inhibited. All these abnormalities were restored to normal after PTX. Depressed lymphocyte activity was found also in the patient with lipoma. However, no change occurred after surgery. These results support the assumption that excess blood levels of PTH may have an immunosuppressive effect.


Assuntos
Hiperparatireoidismo/imunologia , Glândulas Paratireoides/cirurgia , Hormônio Paratireóideo/fisiologia , Linfócitos T/imunologia , Adjuvantes Imunológicos , Adulto , Idoso , Feminino , Humanos , Hiperparatireoidismo/cirurgia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Linfócitos T/classificação
6.
Br J Anaesth ; 49(10): 1027-34, 1977 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-921867

RESUMO

Data on the segmental spread of analgesia from three independent studies of caudal extradural blocks in children with three different local anaesthetic agents were examined with multiple regression techniques to find the effects of age on dose requirements. All three studies confirmed the existence of a linear relationship between the spread of analgesia and age. As there were no significant differences between the three regression lines a common regression line was calculated. This may be used as a guideline for predicting dose requirements in the daily routine of anaesthesia. By injecting a mixture of a radio-opaque substance and 4% lignocaine it was shown by comparison of the radiological spread of the solution and the distribution of clinical analgesia that the latter always exceeded the former by four to six segments. This may indicate the occurrence of diffusion.


Assuntos
Anestesia Caudal , Anestesia Epidural , Fatores Etários , Bupivacaína , Criança , Pré-Escolar , Meios de Contraste , Relação Dose-Resposta a Droga , Humanos , Lactente , Lidocaína , Mepivacaína , Modelos Biológicos , Análise de Regressão
7.
Reg Anaesth ; 5(3): 68-72, 1982 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-6812173

RESUMO

The effects of 2 methods of anaesthesia for gynaecological pelviscopic examinations were compared. For this purpose 28 patients were divided into 2 equal groups (A and B). The patients of group A received a general anaesthetic with intubation, relaxation tic was administered. The patients of group B received an epidural anaesthetic block and were allowed to breathe room air spontaneously. During the procedure the cardiovascular system and changes of blood-gases were observed and recorded. No statistically significant differences in pulse rate and blood pressure between the two groups were found. Blood gases taken prior to anaesthesia and at the end of the procedure revealed a statistically significant decline of the pH. The increase in pCO2 in both groups as well as the rise in base excess in group A were significant. There was no significant difference between both groups. Because of the limited number of cases the statistical results have to be regarded with reservation. No anaesthetic complications occurred. The results show that epidural anaesthesia represents a true alternative to general anaesthesia.


Assuntos
Anestesia Epidural , Anestesia Geral , Endoscopia/métodos , Pelve , Adulto , Idoso , Gasometria , Dióxido de Carbono/sangue , Feminino , Humanos , Concentração de Íons de Hidrogênio , Pessoa de Meia-Idade
8.
Exp Brain Res ; 140(1): 46-55, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11500797

RESUMO

We recorded local field potentials (LFP) in primary (MI) and supplementary (SMA) motor areas of rhesus monkey cortex in order to compare movement-evoked potentials (mEP) in bimanual and unimanual movements with single-unit activity recorded concurrently. The mEP was often different during bimanual and unimanual movements (a "bimanual-related" effect), but, unlike the single units, the size of the mEP in both MI and SMA was always greater during bimanual movements than during unimanual movements. This increase primarily reflected an increase in the late positive peak of the mEP, a result that may reflect greater overall cortical activation during bimanual movements. In addition, analysis of the mEP revealed differences between MI and SMA not seen in the single-unit activity. mEP in MI had greater contralateral preference than in SMA. Also, SMA mEP was more correlated to the single-unit activity than in MI. This greater correlation was also more apparent in the late peaks of the mEP than in the early peaks and may reflect a greater influence of recurrent activation in SMA than in MI. Our results further reinforce the idea that unimanual and bimanual movements are represented differently both in MI and in SMA and also show that a complex relationship between spikes of individual neurons and LFP may reflect the different input-output relations of different cortical areas.


Assuntos
Potencial Evocado Motor/fisiologia , Lateralidade Funcional/fisiologia , Mãos/fisiologia , Córtex Motor/fisiologia , Movimento/fisiologia , Neurônios/fisiologia , Desempenho Psicomotor/fisiologia , Potenciais de Ação/fisiologia , Animais , Feminino , Macaca mulatta , Vias Neurais/fisiologia , Tempo de Reação/fisiologia
9.
Eur J Neurosci ; 15(8): 1371-80, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11994131

RESUMO

Previous studies have shown that activity of neuronal populations in the primary motor cortex (MI), processed by the population vector method, faithfully predicts upcoming movements. In our previous studies we found that single neurons responded differently during movements of one arm vs. combined movements of the two arms. It was, therefore, not clear whether the population vector approach could produce reliable movement predictions also for bimanual movements. This study tests this question by comparing the predictive quality of population vectors for unimanual and bimanual arm movements. We designed a bimanual motor task that requires coordinated movements of the two arms, in which each arm may move in eight directions, and recorded single unit activity in the MI of two rhesus (Macaca mulatta) monkeys during the performance of unimanual and bimanual arm movements. We analysed the activity of 212 MI cells from both hemispheres and found that, despite bimanual related activity, the directional tuning and preferred directions of most cells were preserved in unimanual and bimanual movements. We demonstrate that population vectors, constructed from the activity of MI cells, predict accurately the direction of movement both for unimanual and for bimanual movements even when the two arms move simultaneously in different directions.


Assuntos
Potenciais de Ação/fisiologia , Braço/inervação , Lateralidade Funcional/fisiologia , Macaca mulatta/fisiologia , Córtex Motor/fisiologia , Movimento/fisiologia , Neurônios/fisiologia , Animais , Braço/fisiologia , Feminino , Macaca mulatta/anatomia & histologia , Córtex Motor/citologia , Neurônios/citologia , Orientação/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Transdução de Sinais/fisiologia , Percepção Espacial/fisiologia
10.
J Neurophysiol ; 88(6): 3498-517, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12466464

RESUMO

Single units were recorded from the primary motor (MI) and supplementary motor (SMA) areas of Rhesus monkeys performing one-arm (unimanual) and two-arm (bimanual) proximal reaching tasks. During execution of the bimanual movements, the task related activity of about one-half the neurons in each area (MI: 129/232, SMA: 107/206) differed from the activity during similar displacements of one arm while the other was stationary. The bulk of this "bimanual-related" activity could not be explained by any linear combination of activities during unimanual reaching or by differences in kinematics or recorded EMG activity. The bimanual-related activity was relatively insensitive to trial-to-trial variations in muscular activity or arm kinematics. For example, trials where bimanual arm movements differed the most from their unimanual controls did not correspond to the ones where the largest bimanual neural effects were observed. Cortical localization established by using a mixture of surface landmarks, electromyographic recordings, microstimulation, and sensory testing suggests that the recorded neurons were not limited to areas specifically involved with postural muscles. By rejecting this range of alternative explanations, we conclude that neural activity in MI as well as SMA can reflect specialized cortical processing associated with bimanual movements.


Assuntos
Braço/fisiologia , Atividade Motora/fisiologia , Córtex Motor/fisiologia , Neurônios/fisiologia , Animais , Comportamento Animal/fisiologia , Eletromiografia , Eletrofisiologia , Feminino , Macaca mulatta , Músculo Esquelético/fisiologia , Desempenho Psicomotor/fisiologia
11.
Nature ; 395(6699): 274-8, 1998 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-9751054

RESUMO

Many voluntary movements involve coordination between the limbs. However, there have been very few attempts to study the neuronal mechanisms that mediate this coordination. Here we have studied the activity of cortical neurons while monkeys performed tasks that required coordination between the two arms. We found that most neurons in the primary motor cortex (MI) show activity specific to bimanual movements (bimanual-related activity), which is strikingly different from the activity of the same neurons during unimanual movements. Moreover, units in the supplementary motor area (SMA; the area of cortex most often associated with bimanual coordination) showed no more bimanual-related activity than units in MI. Our results challenge the classic view that MI controls the contralateral (opposite) side of the body and that SMA is responsible for the coordination of the arms. Rather, our data suggest that both cortical areas share the control of bilateral coordination.


Assuntos
Córtex Motor/fisiologia , Desempenho Psicomotor/fisiologia , Animais , Eletromiografia , Extremidades/fisiologia , Feminino , Macaca mulatta , Neurônios Motores/fisiologia
12.
Plant Physiol ; 127(3): 986-97, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11706180

RESUMO

The expression of light-regulated genes in plants is controlled by different classes of photoreceptors that act through a variety of signaling molecules. During photomorphogenesis, the early light-induced protein (Elip) genes are among the first to be induced. To understand the light signal transduction pathways that regulate Elip expression, the two Elip genes, Elip1 and Elip2, in Arabidopsis were studied, taking advantage of the genetic tools available for studying light signaling in Arabidopsis. Using two independent quantitative reverse transcriptase-PCR techniques, we found that red, far-red, and blue lights positively regulate expression of the Elip genes. Phytochrome A and phytochrome B are involved in this signaling. The cryptochrome or phototropin photoreceptors are not required for blue-light induction of either Elip gene, suggesting the involvement of an additional, unidentified, blue-light receptor. Although the COP9 signalosome, a downstream regulator, is involved in dark repression of both Elips, Elip1 and Elip2 show different expression patterns in the dark. The transcription factor HY5 promotes the light induction of Elip1, but not Elip2. A defect in photosystem II activity in greening of hy5 seedlings may result from the loss of Elip1. Heat shock positively controlled Elip1 and Elip2 in a light-independent fashion. This induction is independent of HY5, indicating that heat shock and light activate transcription of the Elip genes through independent pathways.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Proteínas de Drosophila , Proteínas do Olho , Regulação da Expressão Gênica de Plantas , Células Fotorreceptoras de Invertebrados , Células Fotorreceptoras , Proteínas de Plantas/genética , Arabidopsis/metabolismo , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/efeitos da radiação , Fatores de Transcrição de Zíper de Leucina Básica , Clorofila/metabolismo , Clorofila/efeitos da radiação , Criptocromos , Proteínas de Ligação a DNA , Escuridão , Flavoproteínas/metabolismo , Flavoproteínas/efeitos da radiação , Fatores de Transcrição de Choque Térmico , Proteínas de Choque Térmico , Luz , Complexos de Proteínas Captadores de Luz , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/efeitos da radiação , Complexo de Proteínas do Centro de Reação Fotossintética , Complexo de Proteína do Fotossistema II , Fitocromo/metabolismo , Fitocromo/efeitos da radiação , Fitocromo A , Fitocromo B , Proteínas de Plantas/metabolismo , Proteínas de Plantas/efeitos da radiação , Receptores Acoplados a Proteínas G , Transdução de Sinais , Fatores de Transcrição
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