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91.
P van Ruitenbeek A Sambeth A Vermeeren SN Young WJ Riedel 《British journal of pharmacology》2009,157(1):92-103
Background and purpose:
Animal studies show that histamine plays a role in cognitive functioning and that histamine H3-receptor antagonists, which increase histaminergic function through presynaptic receptors, improve cognitive performance in models of clinical cognitive deficits. In order to test such new drugs in humans, a model for cognitive impairments induced by low histaminergic functions would be useful. Studies with histamine H1-receptor antagonists have shown limitations as a model. Here we evaluated whether depletion of L-histidine, the precursor of histamine, was effective in altering measures associated with histamine in humans and the behavioural and electrophysiological (event-related-potentials) effects.Experimental approach:
Seventeen healthy volunteers completed a three-way, double-blind, crossover study with L-histidine depletion, L-tyrosine/L-phenylalanine depletion (active control) and placebo as treatments. Interactions with task manipulations in a choice reaction time task were studied. Task demands were increased using visual stimulus degradation and increased response complexity. In addition, subjective and objective measures of sedation and critical tracking task performance were assessed.Key results:
Measures of sedation and critical tracking task performance were not affected by treatment. L-histidine depletion was effective and enlarged the effect of response complexity as measured with the response-locked lateralized readiness potential onset latency.Conclusions and implications:
L-histidine depletion affected response- but not stimulus-related processes, in contrast to the effects of H1-receptor antagonists which were previously found to affect primarily stimulus-related processes. L-histidine depletion is promising as a model for histamine-based cognitive impairment. However, these effects need to be confirmed by further studies. 相似文献92.
Robert F Anda Maxia Dong David W Brown Vincent J Felitti Wayne H Giles Geraldine S Perry Edwards J Valerie Shanta R Dube 《BMC public health》2009,9(1):106-10
Background
To assess the association between adverse childhood experiences (ACEs), including childhood abuse and neglect, and serious household dysfunction, and premature death of a family member. Because ACEs increase the risk for many of the leading causes of death in adults and tend to be familial and intergenerational, we hypothesized that persons who report having more ACEs would be more likely to have family members at risk of premature death. 相似文献93.
94.
95.
D Gall C Roussel I Susa E D'Angelo P Rossi B Bearzatto MC Galas D Blum S Schurmans SN Schiffmann 《The Journal of neuroscience》2003,23(28):9320-9327
Calcium-binding proteins such as calretinin are abundantly expressed in distinctive patterns in the CNS, but their physiological function remains poorly understood. Calretinin is expressed in cerebellar granule cells, which provide the major excitatory input to Purkinje cells through parallel fibers. Calretinin-deficient mice exhibit dramatic alterations in motor coordination and Purkinje cell firing recorded in vivo through unknown mechanisms. In the present study, we used patch-clamp recording techniques in acute slice preparation to investigate the effect of a null mutation of the calretinin gene on the intrinsic electroresponsiveness of cerebellar granule cells at a mature developmental stage. Calretinin-deficient granule cells exhibit faster action potentials and generate repetitive spike discharge showing an enhanced frequency increase with injected currents. These alterations disappear when 0.15 mm of the exogenous fast-calcium buffer BAPTA is infused in the cytosol to restore the calcium-buffering capacity. A proposed mathematical model demonstrates that the observed alterations of granule cell excitability can be explained by a decreased cytosolic calcium-buffering capacity resulting from the absence of calretinin. This result suggests that calcium-binding proteins modulate intrinsic neuronal excitability and may therefore play a role in information processing in the CNS. 相似文献
96.
97.
CAVH is gaining acceptance as an alternative to traditional therapies for renal failure and diuretic-resistant fluid overload in critical care areas. This article describes precise nursing management techniques and provides a detailed care plan for caring for the patient undergoing this emerging treatment modality. 相似文献
98.
Shanta R. Dube Ralph S. Caraballo Satvinder S. Dhingra William S. Pearson Annette K. McClave Tara W. Strine Joyce T. Berry Ali H. Mokdad 《International journal of public health》2009,54(Z1):68-74
Objectives:
To examine the associations between smoking and quit attempts with psychological distress and also by socioeconomic groups. 相似文献99.
100.
An in-frame deletion of the yopH gene in Yersinia pestis CO92 attenuates virulence in both bubonic and pneumonic plague models. When it is used as a live, attenuated vaccine, CO92 delta yopH provides a high degree of protection from parental and respiratory challenge with Y. pestis CO92. 相似文献