Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
1.
Exp Neurol ; 378: 114815, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38762093

RESUMO

Effective data management and sharing have become increasingly crucial in biomedical research; however, many laboratory researchers lack the necessary tools and knowledge to address this challenge. This article provides an introductory guide into research data management (RDM), and the importance of FAIR (Findable, Accessible, Interoperable, and Reusable) data-sharing principles for laboratory researchers produced by practicing scientists. We explore the advantages of implementing organized data management strategies and introduce key concepts such as data standards, data documentation, and the distinction between machine and human-readable data formats. Furthermore, we offer practical guidance for creating a data management plan and establishing efficient data workflows within the laboratory setting, suitable for labs of all sizes. This includes an examination of requirements analysis, the development of a data dictionary for routine data elements, the implementation of unique subject identifiers, and the formulation of standard operating procedures (SOPs) for seamless data flow. To aid researchers in implementing these practices, we present a simple organizational system as an illustrative example, which can be tailored to suit individual needs and research requirements. By presenting a user-friendly approach, this guide serves as an introduction to the field of RDM and offers practical tips to help researchers effortlessly meet the common data management and sharing mandates rapidly becoming prevalent in biomedical research.


Assuntos
Pesquisa Biomédica , Gerenciamento de Dados , Disseminação de Informação , Humanos , Pesquisa Biomédica/métodos , Pesquisa Biomédica/normas , Gerenciamento de Dados/métodos , Disseminação de Informação/métodos , Pesquisadores
2.
bioRxiv ; 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37503183

RESUMO

Aberrant angiogenesis could contribute to cognitive impairment, representing a therapeutic target for preventing dementia. However, most angiogenesis studies focus on model organisms. To test the relevance of angiogenesis to human cognitive aging, we evaluated associations of circulating blood markers of angiogenesis with brain aging trajectories in two deeply phenotyped human cohorts (n=435, age 74 + 9) with longitudinal cognitive assessments, biospecimens, structural brain imaging, and clinical data. Machine learning and traditional statistics revealed sex dimorphic associations of plasma angiogenic growth factors with brain aging outcomes. Specifically, angiogenesis is associated with higher executive function and less brain atrophy in younger women (not men), a directionality of association that reverses around age 75. Higher levels of basic fibroblast growth factor, known for pleiotropic effects on multiple cell types, predicted favorable cognitive trajectories. This work demonstrates the relevance of angiogenesis to brain aging with important therapeutic implications for vascular cognitive impairment and dementia.

3.
Sci Rep ; 11(1): 3442, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33564058

RESUMO

Traumatic spinal cord injury (SCI) produces a complex syndrome that is expressed across multiple endpoints ranging from molecular and cellular changes to functional behavioral deficits. Effective therapeutic strategies for CNS injury are therefore likely to manifest multi-factorial effects across a broad range of biological and functional outcome measures. Thus, multivariate analytic approaches are needed to capture the linkage between biological and neurobehavioral outcomes. Injury-induced neuroinflammation (NI) presents a particularly challenging therapeutic target, since NI is involved in both degeneration and repair. Here, we used big-data integration and large-scale analytics to examine a large dataset of preclinical efficacy tests combining five different blinded, fully counter-balanced treatment trials for different acute anti-inflammatory treatments for cervical spinal cord injury in rats. Multi-dimensional discovery, using topological data analysis (TDA) and principal components analysis (PCA) revealed that only one showed consistent multidimensional syndromic benefit: intrathecal application of recombinant soluble TNFα receptor 1 (sTNFR1), which showed an inverse-U dose response efficacy. Using the optimal acute dose, we showed that clinically-relevant 90 min delayed treatment profoundly affected multiple biological indices of NI in the first 48 h after injury, including reduction in pro-inflammatory cytokines and gene expression of a coherent complex of acute inflammatory mediators and receptors. Further, a 90 min delayed bolus dose of sTNFR1 reduced the expression of NI markers in the chronic perilesional spinal cord, and consistently improved neurological function over 6 weeks post SCI. These results provide validation of a novel strategy for precision preclinical drug discovery that is likely to improve translation in the difficult landscape of CNS trauma, and confirm the importance of TNFα signaling as a therapeutic target.


Assuntos
Inteligência Artificial , Modelos Neurológicos , Traumatismos da Medula Espinal/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Injeções Espinhais , Ratos Long-Evans , Receptores Tipo I de Fatores de Necrose Tumoral/farmacologia , Proteínas Recombinantes/farmacologia , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/patologia
4.
Sci Adv ; 6(32): eaaz6892, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32821816

RESUMO

Neuroimaging biomarkers that can detect white matter (WM) pathology after mild traumatic brain injury (mTBI) and predict long-term outcome are needed to improve care and develop therapies. We used diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI) to investigate WM microstructure cross-sectionally and longitudinally after mTBI and correlate these with neuropsychological performance. Cross-sectionally, early decreases of fractional anisotropy and increases of mean diffusivity corresponded to WM regions with elevated free water fraction on NODDI. This elevated free water was more extensive in the patient subgroup reporting more early postconcussive symptoms. The longer-term longitudinal WM changes consisted of declining neurite density on NODDI, suggesting axonal degeneration from diffuse axonal injury for which NODDI is more sensitive than DTI. Therefore, NODDI is a more sensitive and specific biomarker than DTI for WM microstructural changes due to mTBI that merits further study for mTBI diagnosis, prognosis, and treatment monitoring.

5.
Exp Neurol ; 293: 144-158, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28412220

RESUMO

Peripheral inflammation induces sensitization of nociceptive spinal cord neurons. Both spinal tumor necrosis factor (TNF) and neuronal membrane insertion of Ca2+ permeable AMPA receptor (AMPAr) contribute to spinal sensitization and resultant pain behavior, molecular mechanisms connecting these two events have not been studied in detail. Intrathecal (i.t.) injection of TNF-blockers attenuated paw carrageenan-induced mechanical and thermal hypersensitivity. Levels of GluA1 and GluA4 from dorsal spinal membrane fractions increased in carrageenan-injected rats compared to controls. In the same tissue, GluA2 levels were not altered. Inflammation-induced increases in membrane GluA1 were prevented by i.t. pre-treatment with antagonists to TNF, PI3K, PKA and NMDA. Interestingly, administration of TNF or PI3K inhibitors followed by carrageenan caused a marked reduction in plasma membrane GluA2 levels, despite the fact that membrane GluA2 levels were stable following inhibitor administration in the absence of carrageenan. TNF pre-incubation induced increased numbers of Co2+ labeled dorsal horn neurons, indicating more neurons with Ca2+ permeable AMPAr. In parallel to Western blot results, this increase was blocked by antagonism of PI3K and PKA. In addition, spinal slices from GluA1 transgenic mice, which had a single alanine replacement at GluA1 ser 845 or ser 831 that prevented phosphorylation, were resistant to TNF-induced increases in Co2+ labeling. However, behavioral responses following intraplantar carrageenan and formalin in the mutant mice were no different from littermate controls, suggesting a more complex regulation of nociception. Co-localization of GluA1, GluA2 and GluA4 with synaptophysin on identified spinoparabrachial neurons and their relative ratios were used to assess inflammation-induced trafficking of AMPAr to synapses. Inflammation induced an increase in synaptic GluA1, but not GluA2. Although total GluA4 also increased with inflammation, co-localization of GluA4 with synaptophysin, fell short of significance. Taken together these data suggest that peripheral inflammation induces a PI3K and PKA dependent TNFR1 activated pathway that culminates with trafficking of calcium permeable AMPAr into synapses of nociceptive dorsal horn projection neurons.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Células do Corno Posterior/metabolismo , Radiculopatia/patologia , Receptores de AMPA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Cálcio/metabolismo , Carragenina/toxicidade , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Etanercepte/uso terapêutico , Feminino , Masculino , Camundongos , Células do Corno Posterior/patologia , Células do Corno Posterior/ultraestrutura , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/fisiologia , Radiculopatia/induzido quimicamente , Radiculopatia/tratamento farmacológico , Ratos Sprague-Dawley , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo , Sinaptofisina/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
6.
Spinal Cord ; 55(6): 559-565, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28220822

RESUMO

STUDY DESIGN: Retrospective analysis. OBJECTIVES: To identify multivariate interactions of respiratory function that are sensitive to spinal cord injury level and pharmacological treatment to promote strategies that increase successful liberation from mechanical ventilation. SETTING: United States regional spinal cord injury (SCI) treatment center. METHODS: Retrospective chart review of patients consecutively admitted to Santa Clara Valley Medical Center between May 2013 and December 2014 for ventilator weaning with C1-C5 American Spinal Injury Association Impairment Scale (AIS) A or B SCI, <3 months from injury and who had a tracheostomy in place. A nonlinear, categorical principal component analysis (NL-PCA) was performed to test the multivariate interaction of respiratory outcomes from patients (N=36) being weaned off ventilator support after acute SCI with (N=15) or without (N=21) theophylline treatment. RESULTS: In total, 36 patients met inclusion criteria (2 C1, 5 C2, 11 C3, 14 C4 and 4 C5). The NL-PCA returned three independent components that accounted for 95% of the variance in the data set. Multivariate general linear models hypothesis tests revealed a significant syndromic interaction between theophylline treatment and SCI level (Wilks' Lambda, P=0.028, F (12,64)=2.116, η2=0.256, 1-ß=0.838), with post hoc testing demonstrating a significant interaction on PC1, explained by a positive correlation between improved forced vital capacity and time it took to reach 16 h of ventilator-free breathing. Thirty-three patients (92%) achieved 16 h of ventilator-free breathing (VFB) and 30 patients (83%) achieved 24 h of VFB. CONCLUSIONS: We suspect that some portion of the high success rate of ventilator weaning may be attributable to theophylline use in higher cervical SCI, in addition to our aggressive regimen of high volume ventilation, medication optimization and pulmonary toilet (positive pressure treatments and mechanical insufflation-exsufflation).


Assuntos
Terapia Respiratória , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/terapia , Doença Aguda , Adolescente , Adulto , Idoso , Vértebras Cervicais , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Dinâmica não Linear , Análise de Componente Principal , Estudos Retrospectivos , Teofilina/uso terapêutico , Traqueostomia , Resultado do Tratamento , Vasodilatadores/uso terapêutico , Adulto Jovem
7.
AJNR Am J Neuroradiol ; 38(3): 648-655, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28007771

RESUMO

BACKGROUND AND PURPOSE: Acute markers of spinal cord injury are essential for both diagnostic and prognostic purposes. The goal of this study was to assess the relationship between early MR imaging biomarkers after acute cervical spinal cord injury and to evaluate their predictive validity of neurologic impairment. MATERIALS AND METHODS: We performed a retrospective cohort study of 95 patients with acute spinal cord injury and preoperative MR imaging within 24 hours of injury. The American Spinal Injury Association Impairment Scale was used as our primary outcome measure to define neurologic impairment. We assessed several MR imaging features of injury, including axial grade (Brain and Spinal Injury Center score), sagittal grade, length of injury, maximum canal compromise, and maximum spinal cord compression. Data-driven nonlinear principal component analysis was followed by correlation and optimal-scaled multiple variable regression to predict neurologic impairment. RESULTS: Nonlinear principal component analysis identified 2 clusters of MR imaging variables related to 1) measures of intrinsic cord signal abnormality and 2) measures of extrinsic cord compression. Neurologic impairment was best accounted for by MR imaging measures of intrinsic cord signal abnormality, with axial grade representing the most accurate predictor of short-term impairment, even when correcting for surgical decompression and degree of cord compression. CONCLUSIONS: This study demonstrates the utility of applying nonlinear principal component analysis for defining the relationship between MR imaging biomarkers in a complex clinical syndrome of cervical spinal cord injury. Of the assessed imaging biomarkers, the intrinsic measures of cord signal abnormality were most predictive of neurologic impairment in acute spinal cord injury, highlighting the value of axial T2 MR imaging.


Assuntos
Biomarcadores , Doenças do Sistema Nervoso/diagnóstico por imagem , Traumatismos da Medula Espinal/diagnóstico por imagem , Adulto , Idoso , Vértebras Cervicais/lesões , Estudos de Coortes , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/fisiopatologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Compressão da Medula Espinal/diagnóstico por imagem , Compressão da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/fisiopatologia , Adulto Jovem
8.
Neuroscience ; 148(4): 893-906, 2007 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-17719180

RESUMO

We have previously shown that the spinal cord is capable of learning a sensorimotor task in the absence of supraspinal input. Given the action of brain-derived neurotrophic factor (BDNF) on hippocampal learning, the current studies examined the role of BDNF in spinal learning. BDNF is a strong synaptic facilitator and, in association with other molecular signals (e.g. cAMP-response element binding protein (CREB), calcium/calmodulin activated protein kinase II (CaMKII) and synapsin I), important for learning. Spinally transected rats given shock to one hind leg when the leg extended beyond a selected threshold exhibited a progressive increase in flexion duration that minimized shock exposure, a simple form of instrumental learning. Instrumental learning resulted in elevated mRNA levels of BDNF, CaMKII, CREB, and synapsin I in the lumbar spinal cord region. The increases in BDNF, CREB, and CaMKII were proportional to the learning performance. Prior work has shown that instrumental training facilitates learning when subjects are tested on the contralateral leg with a higher response criterion. Pretreatment with the BDNF inhibitor TrkB-IgG blocked this facilitatory effect, as did the CaMKII inhibitor AIP. Intrathecal administration of BDNF facilitated learning when subjects were tested with a high response criterion. The findings indicate that instrumental training enables learning and elevates BDNF mRNA levels within the lumbar spinal cord. BDNF is both necessary, and sufficient, to produce the enabling effect.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/fisiologia , Condicionamento Operante/fisiologia , Medula Espinal/metabolismo , Ensino , Regulação para Cima/fisiologia , Análise de Variância , Animais , Comportamento Animal , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Proteína de Ligação a CREB/genética , Proteína de Ligação a CREB/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Condicionamento Operante/efeitos dos fármacos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Inibição Psicológica , Masculino , Ratos , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/reabilitação , Sinapsinas/genética , Sinapsinas/metabolismo , Regulação para Cima/efeitos dos fármacos
9.
Neuroscience ; 141(1): 421-31, 2006 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-16678969

RESUMO

Spinal plasticity is known to play a role in central neurogenic pain. Over the last 100 years researchers have found that the spinal cord is also capable of supporting other forms of plasticity including several forms of learning. To study instrumental (response-outcome) learning in the spinal cord, we use a preparation in which spinally transected rats are given shock to the hind leg when the leg is extended. The spinal cord rapidly learns to hold the leg in a flexed position when given this controllable shock. However, if shock is independent of leg position (uncontrollable shock), subjects fail to learn. Uncontrollable shock also impairs future learning. As little as 6 min of uncontrollable shock to either the leg or the tail generates a learning deficit that lasts up to 48 h. Recent data suggest links between the learning deficit and the sensitization of pain circuits associated with inflammation or injury (central sensitization). Here, we explored whether central sensitization and the spinal learning deficit share pharmacological and behavioral features. Central sensitization enhances reactivity to mechanical stimulation (allodynia) and depends on the N-methyl-d-aspartate receptor (NMDAR). The uncontrollable shock stimulus that generates a learning deficit produced a tactile allodynia (Exp. 1) and administration of the NMDAR antagonist MK-801 blocked induction of the learning deficit (Exp. 2). Finally, a treatment known to induce central sensitization, intradermal carrageenan, produced a spinal learning deficit (Exp. 3). The findings suggest that the induction of central sensitization inhibits selective response modifications.


Assuntos
Condicionamento Psicológico/fisiologia , Inibição Psicológica , Plasticidade Neuronal/fisiologia , Nociceptores/fisiopatologia , Medula Espinal/fisiopatologia , Análise de Variância , Animais , Comportamento Animal , Carragenina/farmacologia , Condicionamento Psicológico/efeitos dos fármacos , Maleato de Dizocilpina/farmacologia , Relação Dose-Resposta a Droga , Antagonistas de Aminoácidos Excitatórios/farmacologia , Lateralidade Funcional , Masculino , Modelos Biológicos , Plasticidade Neuronal/efeitos dos fármacos , Nociceptores/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Medula Espinal/citologia , Medula Espinal/efeitos dos fármacos , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/fisiopatologia
10.
Ann Bot ; 96(7): 1293-305, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16243852

RESUMO

BACKGROUND AND AIMS: Little information is available on DNA C-values for the New Zealand flora. Nearly 85 % of the named species of the native vascular flora are endemic, including 157 species of Poaceae, the second most species-rich plant family in New Zealand. Few C-values have been published for New Zealand native grasses, and chromosome numbers have previously been reported for fewer than half of the species. The aim of this research was to determine C-values and chromosome numbers for most of the endemic and indigenous Poaceae from New Zealand. SCOPE: To analyse DNA C-values from 155 species and chromosome numbers from 55 species of the endemic and indigenous grass flora of New Zealand. KEY RESULTS: The new C-values increase significantly the number of such measurements for Poaceae worldwide. New chromosome numbers were determined from 55 species. Variation in C-value and percentage polyploidy were analysed in relation to plant distribution. No clear relationship could be demonstrated between these variables. CONCLUSIONS: A wide range of C-values was found in the New Zealand endemic and indigenous grasses. This variation can be related to the phylogenetic position of the genera, plants in the BOP (Bambusoideae, Oryzoideae, Pooideae) clade in general having higher C-values than those in the PACC (Panicoideae, Arundinoideae, Chloridoideae + Centothecoideae) clade. Within genera, polyploids typically have smaller genome sizes (C-value divided by ploidy level) than diploids and there is commonly a progressive decrease with increasing ploidy level. The high frequency of polyploidy in the New Zealand grasses was confirmed by our additional counts, with only approximately 10 % being diploid. No clear relationship between C-value, polyploidy and rarity was evident.


Assuntos
Poaceae/genética , Núcleo Celular/genética , DNA de Plantas , Citometria de Fluxo , Genoma de Planta , Nova Zelândia , Ploidias
11.
Scand J Immunol ; 62 Suppl 1: 55-61, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15953185

RESUMO

Secreted IgM is a potent adjuvant that concentrates antigen into secondary lymphoid organs and initiates antibody responses, germinal centre formation and is crucial in resolving infections. The current studies investigated the influence of specific IgM on both the quantity and quality of antibody produced in response to T-dependent and T-independent antigens. The addition of IgM to either antigen had no significant effect on the titre or duration of antibody responses. However, the presence of specific IgM led to accelerated affinity maturation when mice were challenged with low doses of IgM-containing immune complexes (IgM-IC) of T-dependent antigens compared with antigen alone. Interestingly, the administration of higher concentrations of IgM-IC increased follicular deposition of antigen but did not result in accelerated affinity maturation or in higher antibody affinities. The administration of IgM complexed with T-independent antigens had no effect on antibody titre, duration or affinity maturation, despite increased antigen deposition in lymphoid follicles. Together, these results demonstrate that IgM accelerates affinity maturation in immune responses to T-dependent antigens and implies an antigen optimum exists for the generation of high affinity antibodies. The data also suggest IgM plays an important role in the induction of CD4 T cells, facilitating germinal centre formation and function.


Assuntos
Afinidade de Anticorpos , Subpopulações de Linfócitos B/imunologia , Imunoglobulina M/fisiologia , Tecido Linfoide/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Formação de Anticorpos , Subpopulações de Linfócitos B/citologia , Subpopulações de Linfócitos B/metabolismo , Imunidade Celular , Tecido Linfoide/citologia , Tecido Linfoide/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/metabolismo
12.
J Neurotrauma ; 21(1): 109-18, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14987470

RESUMO

Researchers studying the impact of treatments designed to facilitate recovery after neural injury face competing demands. On the one hand, because treatment effects often emerge slowly over days, and because researchers seek evidence of stable long-term effects, it is common practice to observe experimental subjects for many weeks after treatment. On the other hand, the cost of performing studies and the need to evaluate a multitude of alternative treatment procedures requires optimal efficiency, pushing researchers towards shorter test procedures. With these issues in mind, researchers have appeared to derive a test window based on previously published methodologies and inspection of their recovery curves, with testing terminated after the recovery curve reaches asymptote (approaches a slope of 0). An alternative procedure is introduced here that evaluates the stability of the data set over time. Using correlational techniques, researchers can determine whether (1) testing should be continued for additional days; or (2) equivalent statistical power can be achieved in fewer days. This provides a rational decision rule to help researchers balance competing demands. Applying these techniques to a procedure that evaluates the impact of acute treatments on recovery from spinal cord injury, it is shown that equal statistical power can be achieved in half the time, greatly increasing the efficiency with which alternative treatments can be evaluated.


Assuntos
Recuperação de Função Fisiológica/fisiologia , Projetos de Pesquisa , Traumatismos da Medula Espinal/fisiopatologia , Animais , Masculino , Atividade Motora/fisiologia , Ratos , Ratos Sprague-Dawley , Sensibilidade e Especificidade , Fatores de Tempo , Índices de Gravidade do Trauma
13.
J Exp Psychol Anim Behav Process ; 27(3): 219-38, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11497322

RESUMO

Brief-moderate shock (3, 0.75 s, 1.0 mA) has opposite effects on different measures of pain, inducing antinociception on the tail-flick test while lowering vocalization thresholds to shock and heat (hyperalgesia) and enhancing fear conditioned by a gridshock unconditioned stimulus (US). This study examined the generality of shock-induced hyperalgesia under a range of conditions and explored parallels to sensitized startle. Reduced vocalization thresholds to shock and antinociception emerged at a similar shock intensity. Severe shocks (3, 25 s, 1.0 mA or 3, 2 s, 3.0 mA) lowered vocalization threshold to shock but increased vocalization and motor thresholds to heat and undermined fear conditioned by a gridshock or a startling tone US. All shock schedules facilitated startle, but only brief-moderate shock inflated fear conditioning. The findings suggest that brief-moderate shock enhances the affective impact of aversive stimuli, whereas severe shocks attenuate pain.


Assuntos
Hiperalgesia/etiologia , Choque/complicações , Afeto , Animais , Comportamento Animal/fisiologia , Condicionamento Psicológico , Medo , Hiperalgesia/diagnóstico , Aprendizagem , Masculino , Nociceptores/fisiologia , Ratos , Ratos Sprague-Dawley , Reflexo de Sobressalto/fisiologia , Vocalização Animal/fisiologia
14.
Psychopharmacology (Berl) ; 153(2): 180-90, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11205417

RESUMO

RATIONALE: The anxiogenic DMCM, an inverse benzodiazepine agonist, was used to explore the relationship between negative affective states and pain. Past work suggests that the outcome obtained may depend on both the intensity of the affective state and the way in which pain is inferred. OBJECTIVES: The present study was designed to test the impact of relatively low doses of DMCM on multiple measures of pain reactivity and learning. METHODS: In experiment 1, systemic injections of 0.00, 0.015, 0.06, and 0.25 mg/kg DMCM were administered before vocalization and tail movements were assessed in response to a gradually incremented shock and radiant heat stimulus. Experiment 2 tested the effects of DMCM on Pavlovian conditioning. DMCM-treated subjects experienced a context paired with an aversive unconditioned stimulus (US) and conditioned freezing was assessed the next day. RESULTS: Experiment 1 showed that DMCM inhibits both a spinal nociceptive reflex (tail-flick to heat) and a supraspinal measure of pain (vocalization to shock). Because these inhibitory effects could reflect a disruption in motor function, experiment 2 employed a remote test based on Pavlovian conditioning. A moderate dose of DMCM undermined learning, implying that the drug decreased the affective impact of the aversive US. CONCLUSIONS: DMCM induces hypoalgesia on a wide range of assays. Furthermore, pharmacologically inducing a negative affective state blocks Pavlovian fear conditioning. It is suggested that DMCM induces a state of panic and that this state inhibits pain.


Assuntos
Afeto/fisiologia , Carbolinas/farmacologia , Agonistas GABAérgicos/farmacologia , Agonistas de Receptores de GABA-A , Aprendizagem/efeitos dos fármacos , Dor/psicologia , Animais , Condicionamento Psicológico/efeitos dos fármacos , Eletrochoque , Masculino , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos
15.
Percept Mot Skills ; 78(3 Pt 2): 1217-8, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7936945

RESUMO

Although athletes frequently report using music while training or before an event, laboratory studies have not detected a beneficial effect, so the influence of positive and negative music on performance of a selected karate drill was investigated in this double-blind study using 14 volunteers from two Shotokan karate schools. Each subject performed a preselected drill three times following positive and negative music and white noise in a random order. Performance of the drill was rated on a 7-item, 5-point scale by 2 rates. Differences among conditions were assessed via a with-in-subject t test for paired scores. The subjects' self-evaluation of their performance was also examined. Enhancement of performance for both types of music over white noise was significant.


Assuntos
Artes Marciais/psicologia , Música , Adolescente , Adulto , Atitude , Criança , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...