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1.
Health (London) ; : 13634593241238869, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38501283

RESUMO

The lived experiences of higher-weight people vary; homogenous samples may fail to capture this diversity. This study develops an in-depth understanding of the lived experiences of higher-weight (Body Mass Index ⩾ 30) older adults (⩾60 years of age) in a Canadian Atlantic province. Participants (n = 11) were interviewed face-to-face using a semi-structured interview guide twice at 2-to-3-month intervals regarding their perceived treatment in social and health situations; how positive and negative healthcare experiences affected their health, lifestyles and healthcare seeking-behaviour; and recommendations in terms of patient experiences, access and inclusion. Participants infrequently reported negative experiences; however, participants' experiences were informed by uptake of moralistic, neoliberal discourses. Thematic content analysis identified two major themes: active citizenship (participants demonstrated internalisation of the imperative for weight loss, healthy lifestyles and active ageing) and bright-siding (participants expressed that a positive attitude could prevent/help cope with stigma). Results suggest that individualistic, rather than collective, political solutions to health and stigma have been taken up by higher-weight older adults in a Canadian Atlantic province, which may hinder attempts at structural reforms addressing stigma.

2.
Contemp Clin Trials Commun ; 36: 101226, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38034839

RESUMO

The prevalence of obesity is increasing among men, and this population remains under-represented in lifestyle and weight management interventions. The current study aims to explore the experiences of men living with obesity (body fat ≥25 %) toward a 12-week supervised online exercise platform. Ten men were interviewed for this qualitative study. Semi-structured, open-ended phone interviews were conducted, and the transcripts were thematically coded using the qualitative data analysis Nvivo QSR software package. The research findings are illustrated using quotes from participants. The results were organized into two main themes: those that removed barriers to exercise and those that improved the enablers of exercise. Eliminating barriers included not purchasing specialized equipment or travelling to a gym facility. The enablers to their success with the program included the structured format of the circuit program and having supervised sessions. By removing barriers and enhancing enablers, the 12-week online exercise circuit program increased compliance to and success of the exercise program for men living with obesity. Future research should explore the long-term effects of an online program for men living with obesity and its appeal beyond COVID-19.

3.
Chemistry ; 29(37): e202300663, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37074872

RESUMO

Gels formed using a perylene bisimide (PBI) as a low molecular weight gelator can show the photothermal effect. Formation of the PBI radical anion results in new absorption bands forming, meaning that subsequent irradiation with a wavelength of light overlapping with the new absorption band leads to heating of the gel. This approach can be used to heat the gel, as well as the surrounding milieu. We show how we can use electrochemical methods as well as multicomponent systems to form the radical anion without the need for UV light, and how we can use the photothermal effect to induce phase transitions in the solutions above the gels by exploiting photothermal behavior.

4.
ACS Nano ; 16(12): 20497-20509, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36441928

RESUMO

Hierarchical self-assembly is an effective means of preparing useful materials. However, control over assembly across length scales is a difficult challenge, often confounded by the perceived need to redesign the molecular building blocks when new material properties are needed. Here, we show that we can treat a simple dipeptide building block as a polyelectrolyte and use polymer physics approaches to explain the self-assembly over a wide concentration range. This allows us to determine how entangled the system is and therefore how it might be best processed, enabling us to prepare interesting analogues to threads and webs, as well as films that lose order on heating and "noodles" which change dimensions on heating, showing that we can transfer micellar-level changes to bulk properties all from a single building block.

5.
Chem Commun (Camb) ; 58(74): 10388-10391, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36039700

RESUMO

A functionalised dipeptide that self-assembles to form wormlike micelles at high pH can be treated as a surfactant. By varying salt concentration, the self-assembled structures and interactions between them change, resulting in solutions with very different shear and extensional viscosity. From these, gel noodles with different mechanical properties can be prepared.


Assuntos
Micelas , Tensoativos , Tensoativos/química , Viscosidade
6.
Chemistry ; 28(49): e202201725, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35722972

RESUMO

A new flavin-based gelator is reported which forms micellar structures at high pH and gels at low pH. This flavin can be used for the photooxidation of thiols under visible light, with the catalytic efficiency being linked to the self-assembled structures present.


Assuntos
Flavinas , Luz , Catálise , Flavinas/química , Géis/química , Compostos Orgânicos , Oxirredução
7.
J Manipulative Physiol Ther ; 45(8): 551-565, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37341675

RESUMO

OBJECTIVE: The purpose of this paper was to update the previously published 2016 best-practice recommendations for chiropractic management of adults with mechanical low back pain (LBP) in the United States. METHODS: Two experienced health librarians conducted the literature searches for clinical practice guidelines and other relevant literature, and the investigators performed quality assessment of included studies. PubMed was searched from March 2015 to September 2021. A steering committee of 10 experts in chiropractic research, education, and practice used the most current relevant guidelines and publications to update care recommendations. A panel of 69 experts used a modified Delphi process to rate the recommendations. RESULTS: The literature search yielded 14 clinical practice guidelines, 10 systematic reviews, and 5 randomized controlled trials (all high quality). Sixty-nine members of the panel rated 38 recommendations. All but 1 statement achieved consensus in the first round, and the final statement reached consensus in the second round. Recommendations covered the clinical encounter from history, physical examination, and diagnostic considerations through informed consent, co-management, and treatment considerations for patients with mechanical LBP. CONCLUSION: This paper updates a previously published best-practice document for chiropractic management of adults with mechanical LBP.


Assuntos
Quiroprática , Dor Lombar , Manipulação Quiroprática , Adulto , Humanos , Consenso , Dor Lombar/diagnóstico , Dor Lombar/terapia , Exame Físico , Estados Unidos
8.
Chem Sci ; 12(28): 9720-9725, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34349943

RESUMO

Multicomponent supramolecular gels provide opportunities to form materials that are not accessible when using the single components alone. Different scenarios are possible when mixing multiple components, from complete co-assembly (mixing of the components within the self-assembled structures formed) to complete self-sorting such that each structure contains only one of the components. Most examples of multicomponent gels that currently exist form stable gels. Here, we show that this can be used to control the mechanical properties of the gels, but what is probably most exciting is that we show that we can use a magnetic field to control the shape of the crystals. The gelling component aligns in a magnetic field and so results in anisotropic crystals being formed.

9.
Langmuir ; 36(29): 8626-8631, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32614592

RESUMO

It is common to switch between H2O and D2O when examining peptide-based systems, with the assumption being that there are no effects from this change. Here, we describe the effect of changing from H2O to D2O in a number of low-molecular-weight dipeptide-based gels. Gels are formed by decreasing the pH. In most cases, there is little difference in the structures formed at high pH, but this is not universally true. On lowering the pH, the kinetics of gelation are affected and, in some cases, the structures underpinning the gel network are different. Where there are differences in the self-assembled structures, the resulting gel properties are different. We, therefore, show that isotopic control over gel properties is possible.

10.
Macromol Rapid Commun ; 41(10): e2000093, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32297369

RESUMO

The self-assembly of low molecular weight gelators in water usually produces homogeneous hydrogels. However, homogeneous gels are not always desired. Using a photoacid generator, it is shown how to form gels with a transient gradient in stiffness, proved using cavitation and bulk rheology. Small-angle neutron scattering is used to show that the gels formed by photoacid are the result of the same structures as when using a conventional pH trigger. Patterned gels can also be formed, again with transient differences in stiffness.


Assuntos
Hidrogéis/síntese química , Hidrogéis/química , Concentração de Íons de Hidrogênio , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Peso Molecular
11.
Chem Commun (Camb) ; 56(29): 4094-4097, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32162644

RESUMO

The micellar aggregates formed at high pH for dipeptide-based gelators can be varied by using different alkali metal salts to prepare the solutions. The nature of the micellar aggregates directly affects the properties of the resulting gels.


Assuntos
Dipeptídeos/química , Géis , Concentração de Íons de Hidrogênio , Hidróxidos/química , Micelas , Sais
12.
Soft Matter ; 15(31): 6340-6347, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31289805

RESUMO

The study of dipeptide-based hydrogels has been the focus of significant effort recently due to their potential for use in a variety of biomedical and biotechnological applications. It is essential to study the mechanical properties in order to fully characterise and understand this type of soft materials. In terms of mechanical properties, the linear elastic modulus is normally measured using traditional shear rheometry. This technique requires millilitre sample volumes, which can be difficult when only small amounts of gel are available, and can present difficulties when loading the sample into the machine. Here, we describe the use of cavitation rheology, an easy and efficient technique, to characterise the linear elastic modulus of a range of hydrogels. Unlike traditional shear rheometry, this technique can be used on hydrogels in their native environment, and small sample volumes are required. We describe our set-up and show how it can be used to probe and understand different types of gels. Gels can be formed by different triggers from the same gelator and this leads to different microstructures. We show that the data from the cavitational rheometer correlates with the underlying microstructure in the gels, which allows a greater degree of understanding of the gels than can be obtained from the bulk measurements.


Assuntos
Dipeptídeos/química , Hidrogéis/química , Módulo de Elasticidade , Fenômenos Mecânicos , Conformação Molecular , Peso Molecular , Álcool de Polivinil/química , Reologia/métodos
13.
Drug Alcohol Rev ; 31(4): 413-21, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22145930

RESUMO

INTRODUCTION AND AIMS: This study describes levels and predictors of community attitudes towards alcohol, support for structural alterations to the drinking context, and intention to increase participation in community sports clubs. DESIGN AND METHODS: Cross-sectional data were obtained from the VicHealth Community Attitudes Survey on Healthy Sporting Environments, administered to a random sample of Victorian adults. Descriptive and multivariate logistic regression analysis was undertaken. RESULTS: Very high support for removing alcohol sponsorship of community sport and for a levy on alcohol advertising was found. The groups most supportive of breaking the nexus between alcohol and community sport were female, older-aged and non-English-speaking citizens and those not involved in sport clubs. If alcohol sales at community sports clubs were reduced, participation may increase among population groups currently identified as least engaged with community sport. DISCUSSION AND CONCLUSIONS: An optimal climate exists for policy reforms to make community sporting environments healthier by reducing the ties with alcohol. If implemented, these reforms may lead to an increase and diversification of participants in community sport.


Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Intoxicação Alcoólica/psicologia , Atitude Frente a Saúde , Meio Social , Esportes/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Coleta de Dados , Feminino , Comportamentos Relacionados com a Saúde , Promoção da Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Opinião Pública , Vitória
14.
Drug Alcohol Rev ; 31(2): 240-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21824209

RESUMO

INTRODUCTION AND AIMS: To identify general and specific features of health information warning labels on alcohol beverage containers that could potentially inform the development and implementation of a new labelling regime in Australia. DESIGN AND METHODS: Mixed methods, including a cross-sectional population survey and a qualitative study of knowledge, attitudes and behaviours regarding alcohol beverage labelling. The population survey used computer-assisted telephone interviews of 1500 persons in Victoria, Australia to gauge the level of support for health information and warning labels. The qualitative study used six focus groups to test the suitability of 12 prototype labels that were placed in situ on a variety of alcohol beverage containers. RESULTS: The telephone survey found 80% to 90% support for a range of information that could potentially be mandated by government authorities for inclusion on labels (nutritional information, alcohol content, health warning, images). Focus group testing of the prototype label designs found that labels should be integrated with other alcohol-related health messages, such as government social advertising campaigns, and specific labels should be matched appropriately to specific consumer groups and beverage types. DISCUSSION AND CONCLUSION: There are high levels of public support for health information and warning labels on alcohol beverages. This study contributes much needed empirical guidance for developing alcohol beverage labelling strategies in an Australian context.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Bebidas Alcoólicas/efeitos adversos , Rotulagem de Medicamentos , Conhecimentos, Atitudes e Prática em Saúde , Adolescente , Adulto , Publicidade , Estudos Transversais , Coleta de Dados , Feminino , Grupos Focais , Promoção da Saúde/métodos , Humanos , Masculino , Opinião Pública , Telefone , Vitória , Adulto Jovem
15.
Health Promot Int ; 26(4): 397-407, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21208939

RESUMO

An Internet survey was conducted among 511 respondents in Victoria, Australia, to ascertain their support for possible government fruit and vegetable promotion policies. The findings suggest that there is a strong and widespread support for policies which encourage country of origin labelling, local and increased production, subsidies, bans and taxes, and communication campaigns. The respondents' Universalism values (e.g. valuing nature, harmony and beauty) were more pervasive predictors of their opinions than their demographic characteristics. The findings suggest that many Australians hold different views to the prevailing neoliberal views of the political establishment.


Assuntos
Comportamento Alimentar , Frutas , Política de Saúde , Opinião Pública , Verduras , Adolescente , Adulto , Austrália , Coleta de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Vitória , Adulto Jovem
16.
J Pain ; 9(1): 11-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17950674

RESUMO

UNLABELLED: Opiate analgesic tolerance is defined as a need for higher doses of opiates to maintain pain relief after prolonged opiate exposure. Though changes in the opioid receptor undoubtedly occur during conditions of opiate tolerance, there is increasing evidence that opiate analgesic tolerance is also caused by pronociceptive adaptations in the spinal cord. We have previously observed increased glutamate release in the spinal cord dorsal horn of neonatal rats made tolerant to the opiate morphine. In this study, we investigate whether spinal substance P (SP) and its receptor, the neurokinin 1 (NK1) receptor, are also modulated by prolonged morphine exposure. Immunocytochemical studies show decreased SP- and NK1-immunoreactivity in the dorsal horn of morphine-treated rats, whereas SP mRNA in the dorsal root ganglia is not changed. Electrophysiological studies show that SP fails to activate the NK1 receptor in the morphine-treated rat. Taken together, the data indicate that chronic morphine treatment in the neonatal rat is characterized by a loss of SP effects on the NK1 receptor in lamina I of the neonatal spinal cord dorsal horn. The results are discussed in terms of compensatory spinal cord processes that may contribute to opiate analgesic tolerance. PERSPECTIVE: This article describes anatomical and physiological changes that occur in the spinal cord dorsal horn of neonatal rats after chronic morphine treatment. These changes may represent an additional compensatory process of morphine tolerance and may represent an additional therapeutic target for the retention and restoration of pain relief with prolonged morphine treatment.


Assuntos
Analgésicos Opioides/farmacologia , Morfina/farmacologia , Dor/tratamento farmacológico , Células do Corno Posterior/efeitos dos fármacos , Receptores da Neurocinina-1/efeitos dos fármacos , Substância P/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Tolerância a Medicamentos/fisiologia , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Imuno-Histoquímica , Nociceptores/efeitos dos fármacos , Nociceptores/metabolismo , Técnicas de Cultura de Órgãos , Dor/metabolismo , Dor/fisiopatologia , Técnicas de Patch-Clamp , Células do Corno Posterior/metabolismo , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores da Neurocinina-1/metabolismo , Substância P/genética , Substância P/metabolismo
17.
J Neurosci ; 26(46): 12033-42, 2006 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17108177

RESUMO

Repeated exposure to opiates produces analgesic tolerance, which limits their clinical usefulness. Whole-cell voltage-clamped lamina I cells in spinal slices from opiate-tolerant neonatal rats show an increase in miniature, spontaneous, and primary afferent-evoked EPSCs when compared with lamina I cells from opiate-naive rat spinal slices. This increased excitation can be blocked by the NMDA receptor (NMDAR) antagonist APV, apparently acting at NMDARs on primary afferents. Consistent with these results, electron microscopy demonstrates an increased incidence of NMDARs in substance P-containing spinal dorsal horn primary afferent terminals in opiate-tolerant rats. Moreover, superfusion of spinal slices from opiate-tolerant rats with NMDA produces a reversible increase in miniature EPSC (mEPSC) frequency in contrast to a decrease in mEPSC frequency produced by NMDA in opiate-naive slices. Finally, NMDAR antagonists inhibit the expression of opiate tolerance both in inhibiting EPSCs in spinal slices and in inhibiting behavioral nociceptive responses to heat. NMDAR antagonists have been reported in many studies to inhibit morphine analgesic tolerance. Our studies suggest that an increase in primary afferent NMDAR expression and activity mediates a hypersensitivity to noxious stimuli and causes the inhibition of opiate efficacy, which defines tolerance.


Assuntos
Analgésicos Opioides/farmacologia , Tolerância a Medicamentos/fisiologia , Dor/metabolismo , Células do Corno Posterior/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Raízes Nervosas Espinhais/metabolismo , Vias Aferentes/efeitos dos fármacos , Vias Aferentes/metabolismo , Vias Aferentes/ultraestrutura , Envelhecimento/fisiologia , Animais , Animais Recém-Nascidos , Diferenciação Celular/fisiologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Gânglios Espinais/ultraestrutura , Microscopia Imunoeletrônica , Neurônios Aferentes/efeitos dos fármacos , Neurônios Aferentes/metabolismo , Neurônios Aferentes/ultraestrutura , Nociceptores/efeitos dos fármacos , Nociceptores/metabolismo , Dor/tratamento farmacológico , Dor/fisiopatologia , Técnicas de Patch-Clamp , Células do Corno Posterior/efeitos dos fármacos , Células do Corno Posterior/ultraestrutura , Terminações Pré-Sinápticas/efeitos dos fármacos , Terminações Pré-Sinápticas/metabolismo , Terminações Pré-Sinápticas/ultraestrutura , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Raízes Nervosas Espinhais/efeitos dos fármacos , Substância P/metabolismo , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
18.
Neurosci Lett ; 407(1): 64-9, 2006 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-16949209

RESUMO

Opioid analgesic tolerance is a phenomenon defined as a need for increasingly higher doses of opiates to maintain suitable pain relief following repeated drug exposure. Research suggests that analgesic tolerance may result from heightened NMDA receptor (NMDAR) activity, but little is known regarding the mechanisms by which this elevated NMDAR activity develops. Recent evidence suggests that glutamate transporter down-regulation follows repeated opiate exposure and contributes to heightened pain sensitivity. Though glutamate transporter inhibition has been shown to increase activity of spinal cord neurons, it is unknown whether this increase contributes to the heightened NMDAR activity that underlies opiate tolerance. We directly tested this hypothesis by comparing the effects of glutamate transporter inhibition on excitatory post-synaptic currents (EPSCs) in the spinal cord dorsal horn of opiate naïve and opiate tolerant rats. We show that non-selective glutamate transporter inhibition increases the rate of spontaneous excitatory post-synaptic currents (sEPSCs) in the opiate naïve, but not opiate tolerant slice. This potentiation occurs in the presence of the sodium channel blocker tetrodotoxin (TTX) and is blocked by the NMDAR antagonist D-2-amino-5-phosphonovalerate (APV). The sEPSC rate is elevated at baseline in the opiate tolerant spinal cord slice compared to the opiate naïve slice, and glutamate transporter inhibition eliminates this difference. Taken together, we conclude that glutamate transporter inhibition directly contributes to heightened NMDAR activity. Furthermore, we propose that the increased neural activity observed in the opiate tolerant slice is due to a state of glutamate transporter down-regulation and resultant heightened NMDAR activity.


Assuntos
Sistema X-AG de Transporte de Aminoácidos/antagonistas & inibidores , Tolerância a Medicamentos/fisiologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Células do Corno Posterior/efeitos dos fármacos , Medula Espinal/citologia , 2-Amino-5-fosfonovalerato/farmacologia , Análise de Variância , Animais , Ácido Aspártico/farmacologia , Esquema de Medicação , Interações Medicamentosas , Antagonistas de Aminoácidos Excitatórios/farmacologia , Técnicas In Vitro , Ácido Caínico/análogos & derivados , Ácido Caínico/farmacologia , Morfina/efeitos adversos , Entorpecentes/efeitos adversos , Técnicas de Patch-Clamp/métodos , Ratos , Ratos Sprague-Dawley , Medula Espinal/efeitos dos fármacos
19.
Behav Brain Res ; 170(2): 302-7, 2006 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-16621055

RESUMO

Sickness behaviors are a set of adaptive responses to infection that include lethargy, anorexia, and, of direct relevance to this work, learning and memory impairments. The proinflammatory cytokine, interleukin-1 beta (IL-1beta) has been proposed as the primary peripheral mediator of these sickness behaviors, though few studies have investigated the effects of peripheral IL-1beta on learning and memory. We used three different versions of the Morris water task (Morris water task), a spatial learning and memory task, to separately assess the effects of peripheral IL-1beta on acquisition, consolidation, and retention of spatial location information. Using a dose that induced anorexia, assessed as a significant reduction in body weight, we observed no performance impairments in the IL-1beta-treated rats across the different versions of the task, suggesting that peripheral IL-1beta alone is insufficient to induce spatial learning and memory impairments in the rat. The observed dissociation of anorexia and cognitive dysfunction suggests that, either spatial learning and memory are not principal components of the sickness response, or cognitive dysfunction requires different or additional peripheral mediator(s).


Assuntos
Anorexia/induzido quimicamente , Interleucina-1/efeitos adversos , Aprendizagem/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Percepção Espacial/efeitos dos fármacos , Análise de Variância , Animais , Comportamento Animal , Peso Corporal/efeitos dos fármacos , Masculino , Ratos , Ratos Long-Evans , Tempo de Reação/efeitos dos fármacos , Retenção Psicológica/efeitos dos fármacos , Natação
20.
Brain Res Bull ; 67(1-2): 24-9, 2005 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-16140159

RESUMO

Sickness behaviour is an adaptive response to infection that includes lethargy, anorexia and of direct relevance to this work, learning and memory impairments. It has been suggested that proinflammatory cytokines may disrupt learning and memory by interfering with memory consolidation [C.R. Pugh, K. Kumagawa, M. Fleshner, L.R. Watkins, S.F. Maier, J.R. Rudy, Selective effects of peripheral lipopolysaccharide administration on contextual and auditory-cue fear conditioning, Brain Behav. Immun. 12 (1998) 212-229]. We tested whether systemic interleukin-1beta is sufficient to induce impairments in memory consolidation by comparing the effects of post-learning administration of interleukin-1beta with, the potent endotoxin, lipopolysaccharide; and saline, on retention of conditioned fear of a context. We administered an acute intraperitoneal injection of lipopolysaccharide, interleukin-1beta or saline immediately following a single conditioning episode in which rats received two tone-shock pairings. Two days following the learning episode, animals were tested for strength of conditioned responding to both the context and tone. Lipopolysaccharide-injected animals, but not interleukin-1beta-injected animals, exhibited less conditioned fear of context compared to saline-treated controls. All groups showed similar conditioned fear of tone. Our results suggest that systemic interleukin-1beta is not sufficient to disrupt memory consolidation, but rather, the synergistic actions of the proinflammatory cytokines released by lipopolysaccharide are required to disrupt memory consolidation.


Assuntos
Interleucina-1/farmacologia , Lipopolissacarídeos/farmacologia , Transtornos da Memória/imunologia , Estimulação Acústica , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Aprendizagem da Esquiva/fisiologia , Comportamento Animal , Condicionamento Psicológico/efeitos dos fármacos , Condicionamento Psicológico/fisiologia , Relação Dose-Resposta a Droga , Medo/efeitos dos fármacos , Medo/fisiologia , Hipocampo/efeitos dos fármacos , Hipocampo/imunologia , Hipocampo/fisiopatologia , Inflamação/complicações , Inflamação/imunologia , Inflamação/fisiopatologia , Injeções Intraperitoneais , Masculino , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/fisiopatologia , Ratos , Ratos Long-Evans
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