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1.
Angle Orthod ; 81(2): 198-205, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21208069

RESUMO

OBJECTIVE: To collect data regarding Canadian laypersons' perceptions of smile esthetics and compare these data to US data in order to evaluate cultural differences. MATERIALS AND METHODS: Using Adobe Photoshop 7, a digital image of a posed smile of a sexually ambiguous lower face was prepared so that hard and soft tissue could be manipulated to alter buccal corridor (BC), gingival display (GD), occlusal cant (OC), maxillary midline to face discrepancy (MMFD), and lateral central gingival discrepancy (LCGD). Adult Canadian laypersons (n  =  103) completed an interactive computer-based survey of 29 randomized images to compare smile preferences for these variables. The custom survey was developed to display fluid, continuously appearing modifiable smile variables using MATLAB R2008 for presentation. These data were compared with previously published data for US laypersons. Statistical inference was determined using Wilcoxon rank sum tests. RESULTS: Canadian laypersons were more sensitive in detecting deviations from ideal and had a narrower range of acceptability thresholds for BC, GD, OC, MMFD, and LCGD. Ideal esthetic values were significantly different only for BC. CONCLUSIONS: It appears that cultural differences do exist related to smile characteristics. Clinically significant differences in the preference of the smile characteristics were found between Canadian and US laypersons. Canadian laypersons, on average, were more discriminating to deviations from ideal and had a narrower range of acceptability.


Assuntos
Comparação Transcultural , Estética Dentária , Opinião Pública , Sorriso , Adulto , Canadá , Humanos , Processamento de Imagem Assistida por Computador , Estatísticas não Paramétricas , Estados Unidos
2.
Vopr Virusol ; 54(2): 44-7, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19459412

RESUMO

The new highly sensitive test system "DS-EIA-HBsAg-0.01" (Priority Certificate No. 2006129019 of August 10, 2006) in detecting hepatitis B surface antigen (HBsAg) was assessed. The sensitivity of the test was estimated using the federal standards sample HBsAg 42-28-311-06, panels' samples Boston Biomedica Inc. (West Bridgewater, Mass, USA) and ZeptoMetrix Corp. (Buffalo, NY, USA). The findings have indicated that "DS-EIA-HBsAg-0.01" is equally effective in detecting different subtypes of HBsAg during a seroconversion period earlier than alternative assays. Along with its high analytical and diagnostic sensitivity, the system shows a high diagnostic specificity.


Assuntos
Antígenos de Superfície da Hepatite B/análise , Hepatite B/diagnóstico , Kit de Reagentes para Diagnóstico , Hepatite B/imunologia , Humanos , Sensibilidade e Especificidade
3.
Angle Orthod ; 79(3): 428-35, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19413396

RESUMO

OBJECTIVE: To determine the ability to produce comparable superimpositions using hand tracing and digital methods (Dolphin v10). In addition, if the two methods were comparable, we wanted to determine if a difference existed between the best-fit cranial base superimposition and S-N superimpositions using the digital method. METHODS AND MATERIALS: Sixty-four initial (T(1)) and final (T(2)) cephalometric film radiographs were obtained. Cranial base and regional superimpositions were completed independently for each pair of radiographs by either hand tracing and digital methods. To quantitatively evaluate the differences between the two methods, the hand and digital superimpositions were digitized to obtain x-y coordinates of routine cephalometric landmarks at T(2). Linear distance between multiple corresponding (hand and digital) T(2) cephalometric landmark locations (e.g., A point) were measured and defined as the T(2) landmark distance (T(2) LD). Additionally, 61 patient records were used to compare the digital method for best-fit cranial base superimpositions versus S-N superimpositions. A Friedman test was applied to examine for differences. RESULTS: The upper 95% confidence limit for the mean of the T(2) LD for hand and digital superimposition methods was <1 mm for all landmarks except maxillary incisor tip and apex. The upper 95% confidence interval for best-fit vs S-N was >1 mm for most landmarks. CONCLUSION: This study validates the use of superimpositions produced by Dolphin Imaging version 10 and is a necessary step forward toward widespread acceptance of digital superimpositions.


Assuntos
Cefalometria/métodos , Processamento de Imagem Assistida por Computador/métodos , Adolescente , Cefalometria/estatística & dados numéricos , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Incisivo/diagnóstico por imagem , Incisivo/patologia , Masculino , Mandíbula/diagnóstico por imagem , Mandíbula/patologia , Maxila/diagnóstico por imagem , Maxila/patologia , Osso Nasal/diagnóstico por imagem , Osso Nasal/patologia , Radiografia , Sela Túrcica/diagnóstico por imagem , Sela Túrcica/patologia , Base do Crânio/diagnóstico por imagem , Base do Crânio/patologia , Software , Ápice Dentário/diagnóstico por imagem , Ápice Dentário/patologia , Adulto Jovem
4.
Neuroscience ; 161(3): 718-33, 2009 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-19336249

RESUMO

Mu opioid receptor (MOR) signaling in the nucleus accumbens (NAcc) elicits marked increases in the consumption of palatable tastants. However, the mechanism and circuitry underlying this effect are not fully understood. Multiple downstream target regions have been implicated in mediating this effect but the role of the ventral pallidum (VP), a primary target of NAcc efferents, has not been well defined. To probe the mechanisms underlying increased consumption, we identified behavioral changes in rats' licking patterns following NAcc MOR stimulation. Because the temporal structure of licking reflects the physiological substrates modulating consumption, these measures provide a useful tool in dissecting the cause of increased consumption following NAcc MOR stimulation. Next, we used a combination of pharmacological inactivation and lesions to define the role of the VP in hyperphagia following infusion of the MOR-specific agonist [D-Ala2, N-MePhe4, Gly-ol]-enkephalin (DAMGO) into the NAcc. In agreement with previous studies, results from lick microstructure analysis suggest that NAcc MOR stimulation augments intake through a palatability-driven mechanism. Our results also demonstrate an important role for the VP in normal feeding behavior: pharmacological inactivation of the VP suppresses baseline and NAcc DAMGO-induced consumption. However, this interaction does not occur through a serial circuit requiring direct projections from the NAcc to the VP. Rather, our results indicate that NAcc and VP circuits converge on a common downstream target that regulates food intake.


Assuntos
Ingestão de Alimentos/fisiologia , Globo Pálido/fisiologia , Núcleo Accumbens/fisiologia , Receptores Opioides mu/metabolismo , Animais , Cateterismo , Ingestão de Alimentos/efeitos dos fármacos , Ala(2)-MePhe(4)-Gly(5)-Encefalina/administração & dosagem , Comportamento Alimentar/efeitos dos fármacos , Comportamento Alimentar/fisiologia , Agonistas GABAérgicos/administração & dosagem , Globo Pálido/efeitos dos fármacos , Hiperfagia/induzido quimicamente , Hiperfagia/fisiopatologia , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Muscimol/administração & dosagem , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Neurotoxinas/toxicidade , Neurotransmissores/administração & dosagem , Núcleo Accumbens/efeitos dos fármacos , Ácido Quinolínico/toxicidade , Distribuição Aleatória , Ratos , Ratos Long-Evans , Receptores Opioides mu/agonistas , Fatores de Tempo
5.
J Immunoassay Immunochem ; 30(1): 18-39, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19117200

RESUMO

An artificial antigen composed of 12 small antigenic regions derived from the ORF2 and ORF3 HEV proteins was designed. The gene encoding for this artificial antigen was assembled from synthetic oligonucleotides by a new method called Restriction Enzyme-Assisted Ligation (REAL). The diagnostic relevance of this second generation HEV mosaic protein (HEV MA-II) was demonstrated by testing this antigen against a panel of 142 well defined anti-HEV positive and anti-HEV negative serum samples. The data obtained in this study support the substantial diagnostic potential of this HEV mosaic antigen.


Assuntos
Antígenos de Hepatite/imunologia , Vírus da Hepatite E/imunologia , Hepatite E/diagnóstico , Proteínas Recombinantes/imunologia , Proteínas Virais/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Anticorpos Anti-Hepatite/sangue , Anticorpos Anti-Hepatite/imunologia , Antígenos de Hepatite/genética , Hepatite E/imunologia , Humanos , Camundongos , Dados de Sequência Molecular , Oligonucleotídeos/síntese química , Engenharia de Proteínas , Proteínas Recombinantes/genética , Proteínas Virais/genética
6.
Neuroscience ; 155(3): 573-84, 2008 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-18640246

RESUMO

Reward-seeking behavior is controlled by neuronal circuits that include the basolateral nucleus of amygdala (BLA), medial prefrontal cortex (mPFC), nucleus accumbens (NAc) and ventral tegmental area. Using a discriminative stimulus (DS) task in which an intermittently presented cue (DS) directs rats to make an operant response for sucrose, we previously demonstrated that dopamine receptor antagonism in the NAc reduced reinforced cue responding, whereas general inactivation of the NAc increased behavioral responding in the absence of the cue. Because they send major glutamatergic projections to the NAc, the BLA and mPFC may also contribute to reward-seeking behaviors modulated by the NAc. In this study we compare the effects of BLA and mPFC inactivation on rats' performance of a DS task. BLA inactivation by combined GABA(A) and GABA(B) agonists impaired cue responding with minimal effects on operant behavior in the absence of cues. Dorsal medial prefrontal cortex (dmPFC) inactivation also inhibited cue-evoked reward-seeking. In contrast, ventral medial prefrontal cortex (vmPFC) inactivation disinhibited responding to unrewarded cues with less influence on reinforced cue responding. These findings demonstrate that the BLA and dmPFC facilitate cue-evoked reward-seeking, whereas, in the same task the vmPFC exerts inhibitory control over unrewarded behaviors.


Assuntos
Tonsila do Cerebelo/fisiologia , Sinais (Psicologia) , Córtex Pré-Frontal/fisiologia , Reforço Psicológico , Estimulação Acústica/métodos , Tonsila do Cerebelo/efeitos dos fármacos , Análise de Variância , Animais , Baclofeno/farmacologia , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Condicionamento Operante/efeitos dos fármacos , Condicionamento Operante/fisiologia , Discriminação Psicológica/efeitos dos fármacos , Discriminação Psicológica/fisiologia , Relação Dose-Resposta a Droga , Comportamento Exploratório/efeitos dos fármacos , Agonistas GABAérgicos/farmacologia , Masculino , Microinjeções/métodos , Muscimol/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Ratos , Ratos Long-Evans , Tempo de Reação/efeitos dos fármacos , Esquema de Reforço
7.
Vopr Virusol ; 52(3): 13-5, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17601044

RESUMO

Impact of amino acid sequence variation on the antigenic properties of the surface hepatitis B virus antigen HBsAg was studied. Eleven recombinant HBsAg variants of wild (adr, ayw2, adw2, adw4, aywl, adw2) and vaccine escape (adw2 T126S, adw2 Q129L, adw2 Q129R, adw2 T143K, adw2 Q145R, aywl Q145A) were obtained. All the recombinant antigens were tested on a panel of 43 monoclonal antibodies (MAb) specific to different HBsAg determinants. Amino acid sequence variation of the a-determinant of HBsAg was shown to significantly affect its immunological responsiveness and antigenic properties. Amino acid substitution in different positions or in the same position, but for various amino acids may differently affect these properties.


Assuntos
Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/imunologia , Substituição de Aminoácidos/imunologia , Aminoácidos/genética , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Epitopos/imunologia , Variação Genética , Anticorpos Anti-Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Proteínas Recombinantes/imunologia
8.
Neuroscience ; 146(4): 1445-52, 2007 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-17445988

RESUMO

Mu opioid (MOP) agonists acting in the nucleus accumbens (NAcc) robustly enhance consumption of palatable foods. In addition, the effect on consumption of palatable foods produced by MOP agonists acting in the NAcc depends on both recent flavor exposure and the availability of a choice between different-flavored foods. In contrast, kappa opioid (KOP) agonists have variable effects on feeding and KOP agonists have MOP opposing behavioral actions when microinjected at several brain sites. We previously demonstrated that NAcc MOP agonists reverse the devaluation (satiety) effect of pre-feeding for a given flavor; in fact, NAcc MOP agonists selectively increase consumption of a recently sampled food. In contrast, in the present study, we found that the selective KOP agonist U50488 injected into the NAcc of rats reduced consumption of a recently sampled flavor while increasing consumption of the flavor that was not pre-fed. Intra-NAcc U50488 did not affect overall consumption or flavor preference in the absence of pre-feeding. The present data, in conjunction with our previous findings, highlight the robust and opposing role of NAcc MOP and KOP opioid receptors in palatability-based food choice and consumption and raise the possibility that an endogenous KOP agonist acting in the NAcc contributes to the phenomenon of sensory specific satiety.


Assuntos
Analgésicos/farmacologia , Núcleo Accumbens/efeitos dos fármacos , Receptores Opioides kappa/agonistas , Receptores Opioides mu/agonistas , Resposta de Saciedade/efeitos dos fármacos , Análise de Variância , Animais , Comportamento Animal , Preferências Alimentares/efeitos dos fármacos , Masculino , Ratos , Ratos Long-Evans , Receptores Opioides kappa/fisiologia , Receptores Opioides mu/fisiologia , Paladar , Fatores de Tempo
9.
Neuroscience ; 146(1): 19-30, 2007 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-17320293

RESUMO

Opioid signaling in the nucleus accumbens (NAcc) strongly modulates flavor-based food choice. To further investigate the role of opioid signaling in taste reward, we used a sensory specific satiety (SSS) paradigm to devalue specific flavors of nutritionally identical food pellets in rats. In the NAcc, infusion of a mu opioid (MOP) receptor selective agonist selectively increased consumption of a pre-fed flavor, thus reversing the SSS effect. Conversely, blockade of endogenous opioid signaling with the opioid antagonist naltrexone selectively decreased consumption of a recently consumed flavor, potentiating the SSS effect. No enhancement of consumption was observed if a delay of 3 h was imposed following the intra-NAcc MOP agonist indicating that there were no long-term changes in flavor preference. If a delay was introduced between the initial flavor exposure and the intra-NAcc MOP agonist infusion, pellet consumption was increased non-selectively (irrespective of flavor) suggesting that close temporal contiguity between flavor experience and NAcc opioid action is critical for the opioid effect on flavor preference. In contrast to opioid effects, inactivating NAcc neurons by local microinjection of muscimol (a GABAA agonist) increased consumption of both the pre-fed and non-pre-fed flavors equally. These results demonstrate that opioids released in the NAcc during consumption of palatable foods produce a selective and transient increase in preference for a recently sampled flavor.


Assuntos
Analgésicos Opioides/metabolismo , Condicionamento Operante/fisiologia , Preferências Alimentares/fisiologia , Núcleo Accumbens/fisiologia , Transdução de Sinais/fisiologia , Paladar/fisiologia , Analgésicos Opioides/farmacologia , Análise de Variância , Animais , Comportamento Animal , Ingestão de Alimentos/efeitos dos fármacos , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Preferências Alimentares/efeitos dos fármacos , Agonistas GABAérgicos/farmacologia , Masculino , Morfina/farmacologia , Muscimol/farmacologia , Naltrexona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Núcleo Accumbens/efeitos dos fármacos , Ratos , Ratos Long-Evans , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo
10.
Orthod Craniofac Res ; 10(1): 15-21, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17284243

RESUMO

OBJECTIVES: To evaluate the esthetic acceptability range of computer-generated variations in smile arc and buccal corridor. DESIGN: Web-based descriptive study using available subjects. SETTING AND SAMPLE POPULATION: The World Wide Web. Subjects for the main study included 115 lay and 131 orthodontist raters. EXPERIMENTAL VARIABLES: Buccal corridors and smile arcs, each presented for a female and a male image. Buccal corridors were presented as none, ideal and excessive. The smile arc was presented as flat, ideal and excessive. The nine male and female variations, as combinations of the above variables, were each presented twice to evaluate reliability. OUTCOME MEASURE: Acceptability of buccal corridors and smile arcs using the web-based instrument. An arbitrary super majority threshold of acceptability was set at 67% approval. RESULTS: Both laypersons and orthodontists showed good reliability (k >or= 0.70). There was a broad range of acceptability, but laypersons and orthodontists showed no significant differences on the two variables tested. While orthodontists and laypersons both found smiles with excessive buccal corridors to be significantly less acceptable than those with ideal or absent buccal corridors, they were still acceptable over 70% of the time. Flat smile arcs were only acceptable 50-60% of the time, while smiles with ideal and excessive smile arcs were significantly more acceptable 84-95% of the time. When examining buccal corridors and smile arcs together, excessive buccal corridors were significantly less acceptable than ideal or absent buccal corridors regardless of the smile arc. A flat smile arc significantly reduced the acceptability of any buccal corridor to below the threshold of acceptability. CONCLUSIONS: Laypersons and orthodontists have similar preferences when acceptability of buccal corridors and smile arcs are considered. Flat smile arcs are more detrimental to smile esthetics than variations in buccal corridors. Clinicians must realize that although attractiveness may be reduced by variations in buccal corridors and smile arcs, the result may still be acceptable to a majority of people.


Assuntos
Estética Dentária , Lábio/anatomia & histologia , Sorriso/fisiologia , Atitude , Atitude do Pessoal de Saúde , Arco Dental/anatomia & histologia , Feminino , Humanos , Internet , Masculino , Ortodontia , Projetos Piloto , Reprodutibilidade dos Testes , Dente/anatomia & histologia
11.
Neuroscience ; 143(1): 309-17, 2006 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-17049180

RESUMO

Opioid signaling in the nucleus accumbens (NAcc) regulates feeding behavior, having particularly strong effects on consumption of highly palatable foods. Since macronutrient content may contribute to palatability, it is uncertain whether opioid regulation of food consumption is based primarily on its macronutrient content or its flavor per se. In order to isolate the effect of flavor, we manipulated opioid signaling in the NAcc in rats and quantified consumption of differently flavored but nutritionally identical pellets. When pellets of either flavor were presented alone, microinjection of d-Ala(2),N,Me-Phe(4),Gly-ol(5)-enkephalin (DAMGO (a mu opioid receptor (MOP) agonist)) into the NAcc increased consumption of pellets of both flavors equally. When both flavors of pellets were presented simultaneously, however, DAMGO in the NAcc selectively increased, while naltrexone (a non-selective opioid antagonist) in the NAcc selectively decreased, consumption of the more preferred flavor. Systemic naltrexone injection had no flavor specific effects, decreasing consumption of both flavors equally. Non-selective inactivation of NAcc neurons by local microinjection of muscimol (a GABA(A) agonist) increased consumption of both the more- and less-preferred flavors equally. These results indicate that opioid signaling directly regulates a subset of NAcc neurons that can selectively enhance consumption of preferred palatable foods based exclusively on flavor cues.


Assuntos
Analgésicos Opioides/metabolismo , Ingestão de Alimentos/fisiologia , Comportamento Alimentar/efeitos dos fármacos , Núcleo Accumbens/fisiologia , Reforço Psicológico , Analgésicos Opioides/farmacologia , Análise de Variância , Animais , Comportamento Animal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Aromatizantes/farmacologia , Masculino , Naltrexona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Núcleo Accumbens/efeitos dos fármacos , Ratos , Ratos Long-Evans , Fatores de Tempo
12.
Neuroscience ; 135(4): 1025-33, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16165291

RESUMO

The nucleus accumbens is part of the neural circuit that controls reward-seeking in response to reward-predictive cues. Dopamine release in the accumbens is essential for the normal functioning of this circuit. Previous studies have shown that injection of dopamine receptor antagonists into the accumbens severely impairs an animal's ability to perform operant behaviors specified by predictive cues. Furthermore, excitations and inhibitions of accumbens neurons evoked by such cues are abolished by inactivation of the ventral tegmental area, the major dopaminergic input to the accumbens. These results indicate that dopamine is necessary to elicit neural activity in the accumbens that drives the behavioral response to cues. Here we show that accumbens dopamine release is causal to the rats' reward-seeking behavioral response by demonstrating that dopamine in this structure is both necessary and sufficient to promote the appropriate behavioral response to reward-predictive cues.


Assuntos
Comportamento Animal/fisiologia , Sinais (Psicologia) , Dopamina/metabolismo , Núcleo Accumbens/metabolismo , Recompensa , Animais , Comportamento Animal/efeitos dos fármacos , Antagonistas de Dopamina/administração & dosagem , Injeções Intraventriculares , Masculino , Microinjeções , Núcleo Accumbens/efeitos dos fármacos , Ratos , Ratos Long-Evans
13.
APMIS ; 113(7-8): 526-35, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16086823

RESUMO

Human natural killer (NK) cells (CD56+ CD3-) represent crucial components of the innate immune system especially against viral infections and because their activation can modulate the outcome of the adaptive immune response. NKT cells (CD56+CD3+), a lymphocyte T population characterized by expression of surface markers of NK cells, are known to be abundant in the liver and their activation could be associated with hepatic injury. Using three-color flow cytometry to measure surface receptors and intracellular cytokines, we have explored early activation signals and cytokine production in NK and NKT cells within a group of hepatitis B vaccinated and non-vaccinated individuals. A specific increase of the CD56bright cell population, the activation receptor CD69 and IFN-gamma, was observed in NK cells following incubation with recombinant HBsAg in responders to vaccination. Comparable results were observed in NKT cells showing an increment of CD69, CD25, IL-2 and IFN-gamma expression in responder subjects. These parameters were statistically diminished in non-responder individuals (p<0.05) in both groups of cells. These results demonstrate a diminished activation of these cells in non-responders to the vaccine, suggesting that NK and NKT cells play an important role in the immune response following hepatitis B vaccination.


Assuntos
Citocinas/biossíntese , Vacinas contra Hepatite B/administração & dosagem , Células Matadoras Naturais/imunologia , Subpopulações de Linfócitos T/imunologia , Vacinas Sintéticas/administração & dosagem , Adulto , Antígeno CD56/metabolismo , Hepatite B/imunologia , Hepatite B/prevenção & controle , Antígenos de Superfície da Hepatite B/administração & dosagem , Humanos , Imunidade Inata , Interferon gama/biossíntese , Interleucina-2/biossíntese , Ativação Linfocitária , Pessoa de Meia-Idade
14.
J Neurophysiol ; 93(3): 1138-44, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15456805

RESUMO

Microinjection of kappa opioid receptor (KOR) agonists into the rostral ventromedial medulla (RVM) attenuates mu-opioid receptor mediated antinociception and stress-induced analgesia, yet is also reported to have an analgesic effect. To determine how KOR agonists produce both antinociceptive and antianalgesic actions within the RVM, the KOR agonist U69593 was microinjected directly into the RVM while concurrently monitoring tail flick latencies and RVM neuronal activity. Among RVM neurons recorded in vivo, two types show robust changes in activity just prior to the nocifensive tail flick reflex: ON cells burst just prior to a tail flick and their activity is pronociceptive, whereas OFF cells pause just prior to the tail flick and their activity is antinociceptive. Although RVM microinjection of U69593 did not affect tail flick latencies on its own, it did attenuate the on cell burst, an effect blocked by co-injection of the KOR antagonist, nor-binaltorphimine (nor-BNI). Furthermore, U69593 inhibited ongoing activity in subsets of OFF cells (4/11) and NEUTRAL cells (3/9). Microinjection of U69593 into the RVM also attenuated morphine antinociception and suppressed the excitation of off cells. Together with previous in vivo and in vitro studies, these results are consistent with the idea that KOR agonists can be either pronociceptive through direct inhibition of OFF cells, or antianalgesic through both postsynaptic inhibition and presynaptic inhibition of glutamate inputs to RVM OFF cells.


Assuntos
Analgésicos Opioides/farmacologia , Bulbo/citologia , Morfina/farmacologia , Inibição Neural/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Dor/fisiopatologia , Receptores Opioides kappa/fisiologia , Potenciais de Ação/efeitos dos fármacos , Análise de Variância , Animais , Benzenoacetamidas/farmacologia , Interações Medicamentosas , Masculino , Bulbo/fisiopatologia , Microinjeções/métodos , Neurônios/fisiologia , Medição da Dor/métodos , Limiar da Dor/efeitos dos fármacos , Estimulação Física/métodos , Pirrolidinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Opioides kappa/agonistas
15.
Neuroscience ; 121(3): 747-57, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14568033

RESUMO

Drug-associated environmental cues can maintain drug use and contribute to relapse even after long periods of abstinence. We investigated the ability of sensory stimuli that signaled periods of reward availability to sustain cocaine self-administration and trigger the reinstatement of reward-seeking behavior. We demonstrate that lesions of the basolateral amygdala (BLA), a structure strongly implicated in attributing salience to environmental stimuli, significantly reduced the power of predictive cues to elicit reward-seeking behavior. In daily training sessions, a 20 s discriminative stimulus (DS) was presented to rats on a variable interval schedule. If five lever presses were recorded during the DS-on period, then cocaine (0.5 mg/kg) and a conditioned stimulus (CS) were simultaneously delivered. After training, half the animals received excitotoxic lesions of the BLA with quinolinic acid; the other half received saline. Compared with sham-lesioned animals, rats with BLA lesions earned fewer cocaine injections and were less accurate in responding to the DS in the first few days following the lesion. However, they maintained the same cocaine intake as sham-lesioned animals when the DS requirement was lifted. Finally, after seven extinction sessions, reinstatement was measured in response to: 1) i.v. cocaine infusion, 2) DS, 3) CS, 4) a familiar, but non-rewarded cue (S-) or 5) no stimulus. In sham-lesioned animals, cocaine and the DS, but not the CS or the S-, triggered reinstatement. BLA lesions abolished DS-induced reinstatement and significantly attenuated cocaine-induced reinstatement. These results demonstrate 1) that when tested under the same conditions, a discriminative cue which signals reward availability is a more robust trigger of reward-seeking than a Pavlovian CS which signals reward delivery and 2) that the BLA contributes to reinstatement in response to these discriminative cues.


Assuntos
Tonsila do Cerebelo/patologia , Transtornos Relacionados ao Uso de Cocaína/fisiopatologia , Sinais (Psicologia) , Aprendizagem por Discriminação/fisiologia , Tonsila do Cerebelo/fisiopatologia , Animais , Comportamento Animal , Cocaína/administração & dosagem , Condicionamento Operante , Extinção Psicológica , Masculino , Ácido Quinolínico , Ratos , Ratos Long-Evans , Esquema de Reforço , Reforço Psicológico , Autoadministração , Fatores de Tempo
16.
J Neurosci ; 23(21): 7950-7, 2003 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-12944526

RESUMO

Noradrenaline and alpha-adrenoceptors have been implicated in the modulation of pain in various behavioral conditions. Noradrenergic neurons and synaptic inputs are present in neuronal circuits critical for pain modulation, but their actions on neurons in those circuits and consequently the mechanisms underlying noradrenergic modulation of pain remain unclear. In this study, both recordings in vitro and behavioral analyses in vivo were used to examine cellular and behavioral actions mediated by alpha1- and alpha2-adrenoceptors on neurons in the nucleus raphe magnus. We found that alpha1- and alpha2-receptors were colocalized in the majority of a class of neurons (primary cells) that inhibit spinal pain transmission and are excited during opioid analgesia. Activation of the alpha1-receptor depolarized whereas alpha2-receptor activation hyperpolarized these neurons through a decrease and an increase, respectively, in potassium conductance. Blockade of the excitatory alpha1-receptor or activation of the inhibitory alpha2-receptor significantly attenuated the analgesia induced by local opioid application, suggesting that alpha1-receptor-mediated synaptic inputs in these primary cells contribute to their excitation during opioid analgesia. In the other cell class (secondary cells) that is thought to facilitate spinal nociception and is inhibited by analgesic opioids, only alpha1-receptors were present. Blocking the alpha1-receptor in these cells significantly reduced the hyperalgesia (increased pain) induced by opioid abstinence. Thus, state-dependent activation of alpha1-mediated synaptic inputs onto functionally distinct populations of medullary pain-modulating neurons contributes to opioid-induced analgesia and opioid withdrawal-induced hyperalgesia.


Assuntos
Analgésicos Opioides/farmacologia , Hiperalgesia/etiologia , Núcleos da Rafe/fisiologia , Receptores Adrenérgicos alfa 1/fisiologia , Receptores Adrenérgicos alfa 2/fisiologia , Potenciais de Ação , Animais , Células Cultivadas , Condutividade Elétrica , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Masculino , Modelos Neurológicos , Neurônios/química , Neurônios/fisiologia , Norepinefrina/farmacologia , Técnicas de Patch-Clamp , Canais de Potássio/fisiologia , Núcleos da Rafe/citologia , Núcleos da Rafe/efeitos dos fármacos , Ratos , Ratos Wistar , Receptores Adrenérgicos alfa 1/análise , Receptores Adrenérgicos alfa 2/análise , Receptores Opioides mu/agonistas
17.
J Gastroenterol Hepatol ; 17 Suppl 3: S360-4, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12472964

RESUMO

BACKGROUND AND AIM: The purpose of the present study was to develop enzyme immunoassay (EIA) for the detection of IgG anti-hepatitis E virus (HEV) activity using two new recombinant proteins as antigenic targets, and to evaluate these EIA with the aid of statistical methods. METHODS: Two proteins, a mosaic protein and pB166 containing region 452-617 aa of the ORF2 of the HEV Burma strain, were used to develop the new HEV EIA. This EIA was evaluated using several panels of serum specimens obtained from: (i) acutely HEV-infected patients; (ii) patients with non-A, non-C hepatitis; (iii) normal blood donors (NBD) from non-endemic countries; and (iv) experimentally infected chimpanzees. RESULTS: A new HEV EIA was developed using two new recombinant proteins. This assay was able to detect anti-HEV activity in all specimens from acutely HEV-infected patients. When NBD were tested, more than 15% of specimens were found to be IgG anti-HEV positive. All NBD anti-HEV-positive specimens were tested with overlapping synthetic peptides spanning the entire HEV ORF2-encoded protein. More than 90% of the anti-HEV-positive NBD specimens immunoreacted with an average of 15 synthetic peptides derived from different regions of the HEV ORF2 protein. These data suggest that the HEV EIA is at least 90% specific in detecting remote HEV infections. CONCLUSION: The new HEV EIA developed in the present study is a highly specific diagnostic assay for the detection of anti-HEV activity in serum specimens obtained from different epidemiologic settings.


Assuntos
Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/imunologia , Hepatite E/sangue , Técnicas Imunoenzimáticas , Humanos , Proteínas Recombinantes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Proteínas Virais
18.
Immunol Lett ; 83(3): 187-96, 2002 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-12095709

RESUMO

Recombinant DNA containing sequences of HCV NS4 protein was expressed in Escherichia coli cells. Six hybridoma clones producing monoclonal antibodies (MAB) to recombinant NS4 protein (rNS4), aa 1677-1756, were developed. Mapping with a panel of 33 peptides and reciprocal competitive EIA have shown that MAB obtained revealed five antigen determinants, not described earlier: MAB 3F11 and 3F12-one genotype-independent epitope of NS4A (aa 1700-1707) common for genotypes 1, 2 and 3; MAB 1D11-genotype-independent epitope (aa 1713-1728) and MAB 1D3-genotype (subtype 1b)-specific epitope of NS4B (aa 1711-1731); MAB 6B11 and C1-two conformation-dependent determinants in 5-1-1 region. These data indicate that the 5-1-1 region of NS4 protein has a complex antigenic structure and contains at least eight epitopes, including five, revealed in the present work. MAB obtained recognized native viral protein in the cytoplasm of liver cells of patients with chronic hepatitis C. The positive rates of the immunostaining for NS4 antigen using MAB 6B11, 1D11 and 3F12 were 64, 59 and 50%, respectively. It was found that 6B11 MAB to a conformation-dependent epitope much more actively interacts with native NS4 than with the recombinant protein to which MAB was developed. The epitope recognized by 6B11 MAB is highly immunogenic since it induces the B-cell response in all patients investigated with identified anti-NS4 antibodies in blood serum. The MAB panel obtained in this study may become a useful tool for the diagnostic purposes, for the investigation of NS4B function and for the host-viral interactions at the cell level.


Assuntos
Anticorpos Monoclonais/análise , DNA Recombinante , Mapeamento de Epitopos , Hepacivirus/química , Proteínas não Estruturais Virais/análise , Proteínas não Estruturais Virais/imunologia , Animais , Anticorpos Monoclonais/imunologia , Escherichia coli/genética , Feminino , Hepacivirus/imunologia , Hepatite C Crônica/metabolismo , Humanos , Camundongos
19.
Vopr Virusol ; 47(1): 21-5, 2002.
Artigo em Russo | MEDLINE | ID: mdl-11852778

RESUMO

Recombinant protein rNS3 imitating helicase region (1356-1459 amino acid residues) of hepatitis C virus (HCV) was expressed in E. coli cells and used for BALB/c mice immunization. Seven hybrydoma clones producing monoclonal antibodies (MAbs) to rHS3 were obtained. All MAbs reacted in ELISA with NS3 protein from Murex anti-HCV Version III and in immunoblotting from RIBA 3. These MAbs detect 5 individual epitopes, 4 of which were conformational and 1 discontinuous. All MAbs could compete for rNS3 binding with serum antibodies from patients with chronic hepatitis C, which suggests that these MAbs can recognize the natural HCV NS3 protein.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Anti-Hepatite C/imunologia , Proteínas não Estruturais Virais/imunologia , Animais , Anticorpos Monoclonais/isolamento & purificação , Ligação Competitiva , Epitopos/química , Epitopos/isolamento & purificação , Escherichia coli/genética , Vetores Genéticos , Anticorpos Anti-Hepatite C/isolamento & purificação , Hepatite C Crônica/sangue , Hepatite C Crônica/diagnóstico , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Proteínas não Estruturais Virais/biossíntese , Proteínas não Estruturais Virais/genética
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