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1.
J Surg Educ ; 80(9): 1215-1220, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37455191

RESUMO

BACKGROUND: Surgical education is highly dependent on intraoperative communication. Trainers must know the trainee's training level to ensure high-quality surgical training. A systematic preoperative dialogue (Educational Team Time Out, ETO) was established to discuss the steps of each surgical procedure. METHODS: Over 6 months, ETO was performed within a time limit of 3 minutes. Digital surveys on the utility of ETO and its impact on performance were conducted immediately after surgery and at the end of the study period among the staff of the participating disciplines (trainer, trainee, surgical nursing staff, anaesthesiologists, and medical students). The number of surgical substeps performed was recorded and compared with the equivalent period one year earlier. RESULTS: ETO was performed in 64 of the 103 eligible operations (62%). Liver resection (n = 37) was the most frequent procedure, followed by left-sided colorectal surgery (n = 12), partial pancreaticoduodenectomy (n = 6), right-sided hemicolectomies (n = 5), and thyroidectomies (n = 4). Anaesthesiologists most frequently reported that ETO had a direct impact on their work during surgery (90.9%). The influence scores were 46.8% for trainees, 8.8% for trainers, 53.3% for surgical nursing staff and 66.6% for medical students. During the implementation of ETO, a trend towards more assisted substeps in oncologic visceral surgery was seen compared to the corresponding period one year earlier (51% vs.40%; p = 0.11). CONCLUSION: ETO leads to improved intraoperative communication and more performed substeps during complex procedures, which increases motivation and practical training. This concept can easily be implemented in all surgical specialties to improve surgical education.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Internato e Residência , Humanos , Estudos Prospectivos , Currículo , Comunicação
2.
Science ; 284(5421): 1805-11, 1999 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-10364547

RESUMO

Gene-targeted mice lacking the L-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptor subunit GluR-A exhibited normal development, life expectancy, and fine structure of neuronal dendrites and synapses. In hippocampal CA1 pyramidal neurons, GluR-A-/- mice showed a reduction in functional AMPA receptors, with the remaining receptors preferentially targeted to synapses. Thus, the CA1 soma-patch currents were strongly reduced, but glutamatergic synaptic currents were unaltered; and evoked dendritic and spinous Ca2+ transients, Ca2+-dependent gene activation, and hippocampal field potentials were as in the wild type. In adult GluR-A-/- mice, associative long-term potentiation (LTP) was absent in CA3 to CA1 synapses, but spatial learning in the water maze was not impaired. The results suggest that CA1 hippocampal LTP is controlled by the number or subunit composition of AMPA receptors and show a dichotomy between LTP in CA1 and acquisition of spatial memory.


Assuntos
Potenciação de Longa Duração/fisiologia , Aprendizagem em Labirinto , Células Piramidais/fisiologia , Receptores de AMPA/fisiologia , Sinapses/fisiologia , Potenciais de Ação , Animais , Bicuculina/farmacologia , Cálcio/metabolismo , Dendritos/fisiologia , Dendritos/ultraestrutura , Antagonistas GABAérgicos/farmacologia , Expressão Gênica , Marcação de Genes , Genes Precoces , Ácido Glutâmico/farmacologia , Ácido Glutâmico/fisiologia , Hipocampo/citologia , Hipocampo/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Células Piramidais/ultraestrutura , Receptores de AMPA/genética , Receptores de N-Metil-D-Aspartato/fisiologia , Sinapses/ultraestrutura , Transmissão Sináptica
3.
Nat Neurosci ; 5(9): 868-73, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12195431

RESUMO

Gene-targeted mice lacking the AMPA receptor subunit GluR1 (GluR-A) have deficits in hippocampal CA3-CA1 long-term potentiation. We now report that they showed normal spatial reference learning and memory, both on the hidden platform watermaze task and on an appetitively motivated Y-maze task. In contrast, they showed a specific spatial working memory impairment during tests of non-matching to place on both the Y-maze and an elevated T-maze. In addition, successful watermaze and Y-maze reference memory performance depended on hippocampal function in both wild-type and mutant mice; bilateral hippocampal lesions profoundly impaired performance on both tasks, to a similar extent in both groups. These results suggest that different forms of hippocampus-dependent spatial memory involve different aspects of neural processing within the hippocampus.


Assuntos
Hipocampo/fisiopatologia , Potenciação de Longa Duração/genética , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/metabolismo , Vias Neurais/fisiopatologia , Receptores de AMPA/deficiência , Percepção Espacial/fisiologia , Animais , Feminino , Masculino , Transtornos da Memória/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação/genética , Neurônios/metabolismo , Receptores de AMPA/genética , Sinapses/metabolismo , Transmissão Sináptica/fisiologia
4.
J Pharm Sci ; 90(3): 371-88, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11170030

RESUMO

5-Methyl-2-[(4-methyl-2-nitrophenyl)amino]-3-thiophenecarbonitrile is an example of conformational and color polymorphism. The compound crystallizes in red (R), dark red (DR), light red (LR), and orange (O) modifications. There are two specific goals for this study. One is to characterize the complex thermodynamic relationship among these four known forms, and the other is to use the knowledge of the thermodynamic relationship to control the crystallization of these forms. The different forms were characterized by X-ray powder diffractometry as well as Fourier-transform infrared (FT-IR) and Raman spectroscopy; their complex thermodynamic relationships were determined by thermal analysis, solubility measurements, and slurry conversion studies. According to the solubility results, all forms are enantiotropically related: R is the thermodynamically most stable form above 60 degrees C, O is the most stable form between room temperature and 60 degrees C, LR is the most stable form below -15 degrees C, and DR is metastable throughout the entire temperature range. DR, LR, and O have very similar free energy at ambient temperature, which is the reason for the complex transition behavior. Finally, a schematic energy-temperature diagram was constructed that combines all experimental data in a comprehensive thermodynamic picture and provides insights into how to control the crystallization of the individual forms.


Assuntos
Concentração de Íons de Hidrogênio , Tiofenos/química , Varredura Diferencial de Calorimetria , Cristalização , Cristalografia por Raios X , Conformação Molecular , Análise Espectral , Termodinâmica
7.
Biochem J ; 344 Pt 2: 461-7, 1999 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-10567229

RESUMO

Previous studies have demonstrated that amyloid precursor protein (APP) can bind and reduce Cu(II) to Cu(I), leading to oxidative modification of APP. In the present study we show that adding copper to Chinese-hamster ovary (CHO) cells greatly reduced the levels of amyloid Abeta peptide (Abeta) both in parental CHO-K1 and in copper-resistant CHO-CUR3 cells, which have lower intracellular copper levels. Copper also caused an increase in the secretion of the APP ectodomain, indicating that the large decrease in Abeta release was not due to a general inhibition in protein secretion. There was an increase in intracellular full-length APP levels which paralleled the decrease in Abeta generation, suggesting the existence of two distinct regulating mechanisms, one acting on Abeta production and the other on APP synthesis. Maximal inhibition of Abeta production and stimulation of APP secretion was achieved in CHO-K1 cells at about 10 microM copper and in CHO-CUR3 cells at about 50 microM copper. This dose 'window of opportunity' at which copper promoted the non-amyloidogenic pathway of APP was confirmed by an increase in the non-amyloidogenic p3 fragment produced by alpha-secretase cleavage. Our findings suggest that copper or copper agonists might be useful tools to discover novel targets for anti-Alzheimer drugs and may prove beneficial for the prevention of Alzheimer's disease.


Assuntos
Peptídeos beta-Amiloides/biossíntese , Precursor de Proteína beta-Amiloide/metabolismo , Cobre/farmacologia , Fragmentos de Peptídeos/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Sequência de Aminoácidos , Peptídeos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/genética , Relação Dose-Resposta a Droga , Dados de Sequência Molecular , Fragmentos de Peptídeos/genética , Testes de Precipitina , Proteínas Recombinantes/metabolismo
8.
Cell Mol Biol (Noisy-le-grand) ; 46(4): 785-95, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10875440

RESUMO

Previous studies have demonstrated that adding copper to Chinese-hamster ovary (CHO) cells greatly reduced the levels of beta-amyloid (Abeta) peptide in parental CHO-K1 and in copper resistant CHO-CUR3 cells which have lower intracellular copper levels. In the current study, zinc, the zinc chelator 1,10-phenanthroline or copper chelators bathocuproine and D-penicillamine were added to the culture media of stably transfected CHO cells. The data show that zinc up to concentrations of 50 microM or the presence of 1,10-phenanthroline specifically increased the level of secreted APP in CHO-K1 cells. By contrast, the level of secreted APP in CHO-CUR3 cells remained unaffected. APP holoprotein increased dramatically in CHO-CUR3 cells compared with CHO-K1 cells. The large decrease of Abeta release seen in both cell lines at elevated extracellular zinc levels was due to specific inhibition of secretion. These results indicate that a disturbed zinc-homeostasis may be an important factor influencing APP production, transport and processing.


Assuntos
Precursor de Proteína beta-Amiloide/química , Precursor de Proteína beta-Amiloide/metabolismo , Cobre/metabolismo , Zinco/metabolismo , Zinco/farmacologia , Sequência de Aminoácidos , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Animais , Células CHO , Quelantes/farmacologia , Cricetinae , Relação Dose-Resposta a Droga , Resistência a Medicamentos , Eletroforese em Gel de Poliacrilamida , Sequestradores de Radicais Livres/farmacologia , Humanos , L-Lactato Desidrogenase/metabolismo , Dados de Sequência Molecular , Penicilamina/farmacologia , Fenantrolinas/farmacologia , Testes de Precipitina , Transfecção
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