Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 166
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Neurosci ; 40(46): 8951-8963, 2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33046552

RESUMO

It has been argued that the dopaminergic system is involved in the attribution of motivational value to reward predictive cues as well as prediction error. To evaluate, dopamine neurons were recorded from male rats performing a Pavlovian approach task containing cues that have both "predictive" and "incentive" properties. All animals learned the predictive nature of the cue (illuminated lever entry into cage), but some also found the cue to be attractive and were motivated toward it ("sign-trackers," STs). "Goal-trackers" (GTs) predominantly approached the location of reward receptacle. Rats were implanted with tetrodes for neural electrophysiological recordings in the ventral tegmental area. Cells were characterized by spike waveform shape and firing rate. Firing rates and magnitudes of responses in relation to Pavlovian behaviors, cue presentation, and reward delivery were assessed. We identified 103 dopamine and 141 nondopamine neurons. GTs and STs both showed responses to the initial lever presentation (CS1) and lever retraction (CS2). However, higher firing rates were sustained during the lever interaction period only in STs. Further, dopamine cells of STs showed a significantly higher proportion of cells responding to both CS1 and CS2. These are the first results to show that neurons from the VTA encode both predictive and incentive cues, support an important role for dopamine neurons in the attribution of incentive salience to reward-paired cues, and underscore the consequences of potential differences in motivational behavior between individuals.SIGNIFICANCE STATEMENT This project serves to determine whether dopamine neurons encode differences in cued approach behaviors and incentive salience. How neurons of the VTA affect signaling through the NAcc and subsequent dopamine release is still not well known. All cues that precede a reward are predictive in nature. Some, however, also have incentive value, in that they elicit approach toward them. We quantified the attribution of incentive salience through cue approach behavior and cue interaction, and the corresponding magnitude of VTA neural firing. We found dopamine neurons of the VTA encode strength of incentive salience of reward cues. This suggests that dopamine neurons specifically in the VTA encode motivation.


Assuntos
Sinais (Psicologia) , Motivação/fisiologia , Neurônios/fisiologia , Recompensa , Área Tegmentar Ventral/fisiologia , Animais , Comportamento Animal/fisiologia , Condicionamento Clássico/fisiologia , Neurônios Dopaminérgicos/fisiologia , Eletrodos Implantados , Fenômenos Eletrofisiológicos , Individualidade , Masculino , Ratos , Ratos Sprague-Dawley
2.
J Shoulder Elbow Surg ; 27(3): 538-544, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29174018

RESUMO

HYPOTHESIS AND BACKGROUND: The classification and treatment of acromioclavicular (AC) joint dislocations remain controversial. The purpose of this study was to determine the interobserver and intraobserver reliability of the Rockwood classification system. We hypothesized poor interobserver and intraobserver reliability, limiting the role of the Rockwood classification system in determining severity of AC joint dislocations and accurately guiding treatment decisions. METHODS: We identified 200 patients with AC joint injuries using the International Classification of Diseases, Ninth Revision code 831.04. Fifty patients met inclusion criteria. Deidentified radiographs were compiled and presented to 6 fellowship-trained upper extremity orthopedic surgeons. The surgeons classified each patient into 1 of the 6 classification types described by Rockwood. A second review was performed several months later by 2 surgeons. A κ value was calculated to determine the interobserver and intraobserver reliability. RESULTS: The interobserver and intraobserver κ values were fair (κ = 0.278) and moderate (κ = 0.468), respectively. Interobserver results showed that 4 of the 50 radiographic images had a unanimous classification. Intraobserver results for the 2 surgeons showed that 18 of the 50 images were rated the same on second review by the first surgeon and 38 of the 50 images were rated the same on second review by the second surgeon. CONCLUSION: We found that the Rockwood classification system has limited interobserver and intraobserver reliability. We believe that unreliable classification may account for some of the inconsistent treatment outcomes among patients with similarly classified injuries. We suggest that a better classification system is needed to use radiographic imaging for diagnosis and treatment of AC joint dislocations.


Assuntos
Articulação Acromioclavicular/lesões , Radiografia/métodos , Luxação do Ombro/classificação , Articulação Acromioclavicular/diagnóstico por imagem , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Luxação do Ombro/diagnóstico por imagem
3.
J Neurosci ; 36(30): 7957-70, 2016 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-27466340

RESUMO

UNLABELLED: There is considerable individual variation in the extent to which reward cues are attributed with incentive salience. For example, a food-predictive conditioned stimulus (CS; an illuminated lever) becomes attractive, eliciting approach toward it only in some rats ("sign trackers," STs), whereas others ("goal trackers," GTs) approach the food cup during the CS period. The purpose of this study was to determine how individual differences in Pavlovian approach responses are represented in neural firing patterns in the major output structure of the mesolimbic system, the ventral pallidum (VP). Single-unit in vivo electrophysiology was used to record neural activity in the caudal VP during the performance of ST and GT conditioned responses. All rats showed neural responses to both cue onset and reward delivery but, during the CS period, STs showed greater neural activity than GTs both in terms of the percentage of responsive neurons and the magnitude of the change in neural activity. Furthermore, neural activity was positively correlated with the degree of attraction to the cue. Given that the CS had equal predictive value in STs and GTs, we conclude that neural activity in the VP largely reflects the degree to which the CS was attributed with incentive salience. SIGNIFICANCE STATEMENT: Cues associated with reward can acquire motivational properties (i.e., incentive salience) that cause them to have a powerful influence on desire and motivated behavior. There are individual differences in sensitivity to reward-paired cues, with some individuals attaching greater motivational value to cues than others. Here, we investigated the neural activity associated with these individual differences in incentive salience. We found that cue-evoked neural firing in the ventral pallidum (VP) reflected the strength of incentive motivation, with the greatest neural responses occurring in individuals that demonstrated the strongest attraction to the cue. This suggests that the VP plays an important role in the process by which cues gain control over motivation and behavior.


Assuntos
Prosencéfalo Basal/fisiologia , Sinais (Psicologia) , Motivação/fisiologia , Rede Nervosa/fisiologia , Plasticidade Neuronal/fisiologia , Recompensa , Potenciais de Ação/fisiologia , Animais , Atenção/fisiologia , Individualidade , Masculino , Ratos , Análise e Desempenho de Tarefas
4.
J Hand Surg Am ; 42(1): 41-46, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28052827

RESUMO

PURPOSE: Among patients who undergo surgical treatment of terrible triad elbow injuries (TTEI), we hypothesized that those who received perioperative glucocorticoid (GC) therapy would have improved postoperative pain and range of motion (ROM) and a similar complication rate compared with patients who did not receive GC therapy. METHODS: We retrospectively identified 26 patients who underwent surgical treatment of TTEI from 2009 to 2015. Thirteen patients received a single intraoperative dose of 10 mg intravenous dexamethasone followed with a 6-day oral methylprednisolone taper course (GC group), and 13 did not (control group). After surgery, patients were placed in an orthosis at 90° flexion with the forearm in pronation for 2 weeks, after which ROM was initiated. Patients were seen in clinic at 2, 6, 12, and 24 weeks after surgery, at which time numeric pain scale scores and ROM data were collected and any complications were noted. RESULTS: Compared with the control group, the GC group had a greater flexion-extension arc of motion at 24 weeks (132.5° vs 105.5°); significant differences were not found at earlier time points. Supination measurements were significantly greater for the GC group at every time point with a difference at final follow-up of 23.2° (61.0° vs. 84.2°). There were 5 complications in the control group (35.8%), 3 of which required additional surgery, and 3 complications in the GC group (23.1%), 1 of which required another surgery. No postoperative infections were found in either group. CONCLUSIONS: Perioperative glucocorticoid administration is associated with improved ROM after surgical treatment of TTEI. Flexion-extension, pronosupination arc of motion, and overall supination were significantly improved. Postoperative pain scores and complication rates were similar between GC and control groups. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Assuntos
Dexametasona/administração & dosagem , Articulação do Cotovelo/cirurgia , Glucocorticoides/administração & dosagem , Luxações Articulares/cirurgia , Metilprednisolona/administração & dosagem , Fraturas do Rádio/cirurgia , Amplitude de Movimento Articular/efeitos dos fármacos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estudos Retrospectivos , Resultado do Tratamento , Lesões no Cotovelo
5.
Arch Dis Child Educ Pract Ed ; 102(4): 182-187, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28289038

RESUMO

This paper explores the challenges of resolving conflicting feelings around talking with a child about their terminal prognosis. When children are left out of such conversations it is usually done with good intent, with a parent wishing to protect their child from anxiety or loss of hope. There is however growing evidence that sensitive, timely, age appropriate information from those with whom children have a good relationship is helpful both for the child and their family. There is no evidence that involving children in sensitive and timely discussions creates significant problems, rather that withholding information may lead to confusion, frustration, distress and anger. The authors discuss ways in which families can be supported to have these significant conversations with their children.


Assuntos
Atitude Frente a Morte , Comunicação , Cuidados Paliativos/psicologia , Relações Pais-Filho , Pais/psicologia , Doente Terminal/psicologia , Revelação da Verdade , Adolescente , Criança , Feminino , Humanos , Masculino
6.
Eur J Neurosci ; 44(7): 2431-2445, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27422085

RESUMO

We investigated the potential of deep brain stimulation (DBS) in the central nucleus of the amygdala (CeA) in rats to modulate functional reward mechanisms. The CeA is the major output of the amygdala with direct connections to the hypothalamus and gustatory brainstem, and indirect connections with the nucleus accumbens. Further, the CeA has been shown to be involved in learning, emotional integration, reward processing, and regulation of feeding. We hypothesized that DBS, which is used to treat movement disorders and other brain dysfunctions, might block reward motivation. In rats performing a lever-pressing task to obtain sugar pellet rewards, we stimulated the CeA and control structures, and compared stimulation parameters. During CeA stimulation, animals stopped working for rewards and rejected freely available rewards. Taste reactivity testing during DBS exposed aversive reactions to normally liked sucrose tastes and even more aversive taste reactions to normally disliked quinine tastes. Interestingly, given the opportunity, animals implanted in the CeA would self-stimulate with 500 ms trains of stimulation at the same frequency and current parameters as continuous stimulation that would stop reward acquisition. Neural recordings during DBS showed that CeA neurons were still active and uncovered inhibitory-excitatory patterns after each stimulus pulse indicating possible entrainment of the neural firing with DBS. In summary, DBS modulation of CeA may effectively usurp normal neural activity patterns to create an 'information lesion' that not only decreased motivational 'wanting' of food rewards, but also blocked 'liking' of rewards.


Assuntos
Comportamento Animal/fisiologia , Núcleo Central da Amígdala/fisiologia , Estimulação Encefálica Profunda , Preferências Alimentares/fisiologia , Motivação/fisiologia , Recompensa , Animais , Comportamento Alimentar/fisiologia , Alimentos , Masculino , Núcleo Accumbens/fisiologia , Ratos Sprague-Dawley
7.
Health Expect ; 18(6): 2570-83, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24975503

RESUMO

BACKGROUND: Informed consent is required for both standard cancer treatments and experimental cancer treatments in a clinical trial. Effective and sensitive physician-patient communication about informed consent is difficult to achieve. Our aim was to train doctors in clear, collaborative and ethical communication about informed consent and evaluate the impact of training on doctor behaviour, stress and satisfaction. PARTICIPANTS AND METHODS: Participants were 21 oncologists from 10 Australian/New Zealand (ANZ) centres and 41 oncologists from 10 Swiss/German/Austrian (SGA) centres. Oncologists were randomized to participate in a 1-day workshop or not. Patients were recruited before and after the training. Doctors were asked to submit 1-2 audiotaped consultations before and after training. Doctors completed outcome measures before and after completing the post-training cohort recruitment. RESULTS: Ninety-five consultation interactions were audiotaped. Doctors strongly endorsed the training. ANZ intervention doctors demonstrated a significant increase in collaborative communication (P = 0.03). There was no effect of training on other doctor behaviours. Trained doctors did not demonstrate reduced stress and burnout. Patient outcomes are presented elsewhere. CONCLUSIONS: Training can improve some aspects of the process of obtaining informed consent. Methods to increase the impact of training are required and may include longer training and more intensive follow-up.


Assuntos
Participação do Paciente , Seleção de Pacientes , Relações Médico-Paciente , Neoplasias da Mama/terapia , Competência Clínica , Comunicação , Educação , Educação Médica Continuada , Feminino , Humanos , Consentimento Livre e Esclarecido/psicologia , Masculino , Pessoa de Meia-Idade , Encaminhamento e Consulta , Gravação em Fita
8.
Proc Natl Acad Sci U S A ; 108(27): E255-64, 2011 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-21670308

RESUMO

Multiple signals for reward-hedonic impact, motivation, and learned associative prediction-are funneled through brain mesocorticolimbic circuits involving the nucleus accumbens and ventral pallidum. Here, we show how the hedonic "liking" and motivation "wanting" signals for a sweet reward are distinctly modulated and tracked in this circuit separately from signals for Pavlovian predictions (learning). Animals first learned to associate a fixed sequence of Pavlovian cues with sucrose reward. Subsequent intraaccumbens microinjections of an opioid-stimulating drug increased the hedonic liking impact of sucrose in behavior and firing signals of ventral pallidum neurons, and likewise, they increased incentive salience signals in firing to the reward-proximal incentive cue (but did not alter firing signals to the learned prediction value of a reward-distal cue). Microinjection of a dopamine-stimulating drug instead enhanced only the motivation component but did not alter hedonic impact or learned prediction signals. Different dedicated neuronal subpopulations in the ventral pallidum tracked signal enhancements for hedonic impact vs. incentive salience, and a faster firing pattern also distinguished incentive signals from slower hedonic signals, even for a third overlapping population. These results reveal separate neural representations of wanting, liking, and prediction components of the same reward within the nucleus accumbens to ventral pallidum segment of mesocorticolimbic circuitry.


Assuntos
Aprendizagem/fisiologia , Motivação/fisiologia , Prazer/fisiologia , Recompensa , Anfetamina/farmacologia , Analgésicos Opioides/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Sinais (Psicologia) , Dopamina/farmacologia , Fenômenos Eletrofisiológicos , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Globo Pálido/efeitos dos fármacos , Globo Pálido/fisiologia , Aprendizagem/efeitos dos fármacos , Masculino , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/fisiologia , Ratos , Ratos Sprague-Dawley , Reforço Psicológico
9.
J Hand Surg Am ; 39(7): 1301-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24793227

RESUMO

PURPOSE: To evaluate union and complication rates associated with the use of 2 headless compression screws and bone grafting for the treatment of scaphoid nonunions. METHODS: A total of 19 patients (18 male and 1 female) at an average age of 21 years were treated with open reduction and internal fixation with 2 cannulated, headless, compression screws for scaphoid nonunions. Bone grafting techniques included corticocancellous autograft from the iliac crest in 14 patients, capsular-based vascularized distal radius graft in 3, and medial femoral condyle free vascularized bone graft in 2. Patients were treated an average 19 months after the injury. Fracture nonunions were at the waist (n = 12), proximal third (n = 5), or distal third (n = 2) of the scaphoid. Dorsal (n = 7) and volar (n = 12) surgical approaches were used. RESULTS: All fractures had clinical and radiographic evidence of bone union at an average of 3.6 months. Postoperative computed tomography scans were available in 13 patients and showed union without evidence of screw penetration of the scaphoid cortex. No complications occurred in this series, and no revision procedures have been necessary. CONCLUSIONS: Our results indicate that the use of 2 headless compression screws for the treatment of scaphoid nonunions is safe and effective. A variety of bone grafting techniques can be used with this technique. The use of 2 compression screws may provide superior biomechanical stability and ultimately improve outcomes measured with future long-term comparative studies. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Assuntos
Parafusos Ósseos , Transplante Ósseo/métodos , Fixação Interna de Fraturas/instrumentação , Fraturas não Consolidadas/cirurgia , Osso Escafoide/lesões , Osso Escafoide/cirurgia , Adulto , Artroscopia/métodos , Estudos de Coortes , Terapia Combinada/métodos , Desenho de Equipamento , Feminino , Seguimentos , Fixação Interna de Fraturas/métodos , Consolidação da Fratura/fisiologia , Fraturas não Consolidadas/diagnóstico por imagem , Humanos , Escala de Gravidade do Ferimento , Masculino , Medição da Dor , Estudos Retrospectivos , Medição de Risco , Osso Escafoide/diagnóstico por imagem , Fatores de Tempo , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Adulto Jovem
10.
Br J Cancer ; 108(6): 1273-9, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23449361

RESUMO

BACKGROUND: Despite advances in the treatment of childhood cancer, some children continue to die from their disease. This study aimed to assess the impact of specialist paediatric palliative care services (SPPCSs) on the number of hospital admissions in children who subsequently died from cancer in Yorkshire, UK. METHODS: An extract of patients aged 0-19 years from the Yorkshire Specialist Register of Cancer in Children and Young People (YSRCCYP) diagnosed from 1990 to 2009 were linked to inpatient hospital episodes data and a SPPCS database. Deaths were included if they occurred before 31 August 2011. Differences in hospital admission patterns were assessed using negative binomial regression and presented as incidence rate ratios (IRRs). RESULTS: Of 2508 children on the YSRCCYP, 657 (26%) had died by the censoring date. A total of 211 children had been referred to the local SPPCS, of whom 182 (86%) had subsequently died. Referral to SPPCS was associated with a significant reduction in the rate of planned hospital admissions (IRR=0.60, 95% CI 0.43-0.85). Central nervous system tumours showed significant decreases for all planned and emergency admissions compared with all other diagnostic groups. CONCLUSION: Referral to SPPCS significantly reduced the number of planned hospital admissions for children and young people with cancer before their death, which are often integral to paediatric oncology treatment regimens. Overall, our findings show that SPPCS have a role in reducing hospital admissions during end of life care of paediatric cancer patients with potential personal, social and economic benefits.


Assuntos
Hospitalização/estatística & dados numéricos , Neoplasias/terapia , Cuidados Paliativos , Admissão do Paciente/estatística & dados numéricos , Encaminhamento e Consulta , Especialização/estatística & dados numéricos , Assistência Terminal , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Prognóstico , Adulto Jovem
11.
Eur J Neurosci ; 37(6): 901-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23279008

RESUMO

Data from preclinical and clinical studies have implicated the norepinephrine system in the development and maintenance of post-traumatic stress disorder. The primary source of norepinephrine in the forebrain is the locus coeruleus (LC); however, LC activity cannot be directly measured in humans, and previous research has often relied upon peripheral measures of norepinephrine to infer changes in central LC-norepinephrine function. To directly assess LC-norepinephrine function, we measured single-unit activity of LC neurons in a validated rat model of post-traumatic stress disorder - single prolonged stress (SPS). We also examined tyrosine hydroxylase mRNA levels in the LC of SPS and control rats as an index of norepinephrine utilisation. For electrophysiological recordings, 92 LC neurons were identified from 19 rats (SPS, 12; control, 7), and spontaneous and evoked responses to a noxious event (paw compression) were recorded. Baseline and restraint stress-evoked tyrosine hydroxylase mRNA expression levels were measured in SPS and control rats (n = 16 per group) in a separate experiment. SPS rats showed lower spontaneous activity but higher evoked responses, leading to an enhanced signal-to-noise ratio of LC neurons, accompanied by impaired recovery from post-stimulus inhibition. In concert, tyrosine hydroxylase mRNA expression in the LC of SPS rats tended to be lower at baseline, but was exaggerated following restraint stress. These data demonstrate persistent changes in LC function following stress/trauma in a rat model of post-traumatic stress, as measured by differences in both the electrophysiological properties of LC neurons and tyrosine hydroxylase mRNA transcription.


Assuntos
Locus Cerúleo/metabolismo , Norepinefrina/metabolismo , Estresse Psicológico/fisiopatologia , Potenciais de Ação , Animais , Locus Cerúleo/citologia , Locus Cerúleo/fisiopatologia , Masculino , Inibição Neural , Neurônios/metabolismo , Neurônios/fisiologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Restrição Física , Transtornos de Estresse Pós-Traumáticos/metabolismo , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Estresse Psicológico/metabolismo , Transcrição Gênica , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo
12.
Ann Oncol ; 24(2): 391-397, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23019277

RESUMO

BACKGROUND: The purpose was to investigate patient-doctor agreement on clinical trial discussion cross-culturally. METHODS: In the International Breast Cancer Study Group Trial 33-03 on shared decision-making for early breast cancer in Australian/New Zealand (ANZ) and Swiss/German/Austrian (SGA) centers, doctor and patient characteristics plus doctor stress and burnout were assessed. Within 2 weeks post-consultation about treatment options, the doctor and patient reported independently, whether a trial was discussed. Odds ratios of agreement for covariables were estimated by generalized estimating equations for each language cohort, with doctor as a random effect. RESULTS: In ANZ, 21 doctors and 339 patients were eligible; in SGA, 41 doctors and 427 patients. In cases where the doctor indicated 'no trial discussed', 82% of both ANZ and SGA patients agreed; if the doctor indicated 'trial discussed', 50% of ANZ and 38% of SGA patients agreed, respectively. Factors associated with higher agreement were: low tumor grade and fewer patients recruited into clinical trials in SGA; public institution, patient born in ANZ (versus other), higher doctor depersonalization and personal accomplishment in ANZ. CONCLUSION: There is discordance between oncologists and their patients regarding clinical trial discussion, particularly when the doctor indicates that a trial was discussed. Factors contributing to this agreement vary by culture.


Assuntos
Neoplasias da Mama/terapia , Ensaios Clínicos como Assunto , Tomada de Decisões , Relações Médico-Paciente , Comunicação , Compreensão , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Rememoração Mental , Estresse Psicológico
13.
Nano Lett ; 12(3): 1269-74, 2012 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-22280452

RESUMO

We have developed arrays of nanomechanical systems (NEMS) by large-scale integration, comprising thousands of individual nanoresonators with densities of up to 6 million NEMS per square centimeter. The individual NEMS devices are electrically coupled using a combined series-parallel configuration that is extremely robust with respect to lithographical defects and mechanical or electrostatic-discharge damage. Given the large number of connected nanoresonators, the arrays are able to handle extremely high input powers (>1 W per array, corresponding to <1 mW per nanoresonator) without excessive heating or deterioration of resonance response. We demonstrate the utility of integrated NEMS arrays as high-performance chemical vapor sensors, detecting a part-per-billion concentration of a chemical warfare simulant within only a 2 s exposure period.


Assuntos
Gases/análise , Sistemas Microeletromecânicos/instrumentação , Nanotecnologia/instrumentação , Transdutores , Desenho de Equipamento , Análise de Falha de Equipamento , Integração de Sistemas
14.
Can J Dent Hyg ; 57(2): 123-131, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37464993

RESUMO

Background: Charcoal-based preparations have recently gained popularity, particularly in oral hygiene products such as tooth whitening dentifrices, owing to their abrasive and adsorptive properties. The present in vitro study evaluates the efficacy of a charcoal-based tooth whitening dentifrice compared with a non-charcoal-based whitening dentifrice in removing coffee stains on tooth surfaces. Methods: Thirty-three human extracted tooth specimens were randomly assigned to 1 of 3 study groups: Group 1 (charcoal-based whitening dentifrice [CBWD]), Group 2 (non-charcoal-based whitening dentifrice [NCBWD]), and Group 3 (distilled water [DW]). All tooth specimens were immersed in a prepared coffee extract for 4 weeks to facilitate staining and then mounted on blocks where they were brushed with an electric toothbrush daily for 8 seconds with 1 of the 2 allocated dentifrices or with DW for 4 weeks following staining. Spectrophotometric analysis was conducted using the CIELAB system to measure the L*, a*, and b* values at 3 time points: before staining, after staining, and following the brushing protocol. These values were used to calculate the colour change (ΔE) between time points. Results: Following the coffee staining, the tooth samples' whiteness (ΔL) decreased with the overall colour change (ΔE). Next, there was a significant improvement in the degree of tooth whiteness (ΔL) values following the brushing protocol in all 3 groups (p = 0.003), with the greatest improvement occurring in the CBWD group. However, the overall colour change (ΔE) was not significantly different between the groups. Conclusion: CBWD, NCBWD, and DW were effective in removing coffee stains from the tooth surface. However, the amount of colour change (ΔE) produced by CBWD was not significantly different from NCBWD or DW.


Introduction: Les préparations à base de charbon ont récemment gagné en popularité, en particulier dans les produits d'hygiène buccale comme les dentifrices blanchissants, en raison de leurs propriétés d'abrasion et d'adsorption. La présente étude in vitro évalue l'efficacité d'un dentifrice blanchissant à base de charbon par rapport à un dentifrice blanchissant sans charbon pour éliminer les taches de café sur la surface des dents. Méthodes: Trente-trois spécimens de dents humaines extraites ont été répartis aléatoirement dans 3 groupes d'étude : groupe 1 (dentifrice blanchissant à base de charbon [DBBC]), groupe 2 (dentifrice blanchissant sans charbon [DSC]) et groupe 3 (eau distillée [ED]). Tous les spécimens de dents ont été immergés dans une préparation de café pendant 4 semaines pour permettre la coloration, puis montés sur des blocs où ils ont été brossés quotidiennement à la brosse à dents électrique pendant 8 secondes avec l'un des deux dentifrices testés ou avec de l'eau distillée pour une période de 4 semaines après la coloration. Une analyse spectrophotométrique a été effectuée à l'aide du système CIELAB pour mesurer les valeurs L*, a* et b* à 3 moments précis : avant la coloration, après la coloration et après le protocole de brossage. Ces valeurs ont été utilisées pour calculer le changement de couleur (ΔE) entre les moments précis. Résultats: Après la coloration du café, la blancheur des échantillons de dents (ΔL) a diminué en raison du changement global de couleur (ΔE). Ensuite, il y a eu une amélioration significative du degré de blancheur des dents (ΔL) suivant le protocole de brossage dans les 3 groupes (p = 0,003), la plus grande amélioration ayant eu lieu dans le groupe DBBC. Toutefois, le changement global de couleur (ΔE) n'était pas significativement différent d'un groupe à l'autre. Conclusion: Les DBBC, DSC et l'ED se sont montrés efficaces pour éliminer les taches de café sur la surface des dents. Toutefois, le changement de couleur (ΔE) produit par le DBBC n'était pas significativement différent de celui produit par le DSC ou l'ED.


Assuntos
Dentifrícios , Clareamento Dental , Descoloração de Dente , Humanos , Carvão Vegetal/uso terapêutico , Corantes , Dentifrícios/uso terapêutico , Dióxido de Silício , Fluoreto de Sódio , Coloração e Rotulagem , Clareamento Dental/métodos , Descoloração de Dente/tratamento farmacológico , Café/efeitos adversos
15.
Br J Cancer ; 106(10): 1618-25, 2012 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-22531635

RESUMO

BACKGROUND: In the BIG 1-98 trial objective cognitive function improved in postmenopausal women 1 year after cessation of adjuvant endocrine therapy for breast cancer. This report evaluates changes in subjective cognitive function (SCF). METHODS: One hundred postmenopausal women, randomised to receive 5 years of adjuvant tamoxifen, letrozole, or a sequence of the two, completed self-reported measures on SCF, psychological distress, fatigue, and quality of life during the fifth year of trial treatment (year 5) and 1 year after treatment completion (year 6). Changes between years 5 and 6 were evaluated using the Wilcoxon signed-rank test. Subjective cognitive function and its correlates were explored. RESULTS: Subjective cognitive function and the other patient-reported outcomes did not change significantly after cessation of endocrine therapy with the exception of improvement for hot flushes (P=0.0005). No difference in changes was found between women taking tamoxifen or letrozole. Subjective cognitive function was the only psychosocial outcome with a substantial correlation between year 5 and 6 (Spearman's R=0.80). Correlations between SCF and the other patient-reported outcomes were generally low. CONCLUSION: Improved objective cognitive function but not SCF occur following cessation of adjuvant endocrine therapy in the BIG 1-98 trial. The substantial correlation of SCF scores over time may represent a stable attribute.


Assuntos
Inibidores da Aromatase/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Cognição/efeitos dos fármacos , Antagonistas de Estrogênios/efeitos adversos , Nitrilas/efeitos adversos , Tamoxifeno/efeitos adversos , Triazóis/efeitos adversos , Neoplasias da Mama/patologia , Neoplasias da Mama/psicologia , Feminino , Humanos , Letrozol , Estadiamento de Neoplasias , Qualidade de Vida
16.
Ann Oncol ; 23(5): 1138-1144, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21986093

RESUMO

BACKGROUND: Estrogen Receptor 1 (ESR1) aberrations may be associated with expression of estrogen receptor (ER) or progesterone receptor (PgR), human epidermal growth factor receptor-2 (HER2) or Ki-67 labeling index and prognosis. PATIENTS AND METHODS: ESR1 was assessed in 1129 (81%) of 1396 postmenopausal Danish women with early breast cancer randomly assigned to receive 5 years of letrozole, tamoxifen or a sequence of these agents in the Breast International Group 1-98 trial and who had ER ≥ 1% after central review. RESULTS: By FISH, 13.6% of patients had an ESR1-to-Centromere-6 (CEN-6) ratio ≥ 2 (amplified), and 4.2% had ESR1-to-CEN-6 ratio <0.8 (deleted). Deletion of ESR1 was associated with significantly lower levels of ER (P < 0.0001) and PgR (P = 0.02) and more frequent HER2 amplification. ESR1 deletion or amplification was associated with higher-Ki-67 than ESR1-normal tumors. Overall, there was no evidence of heterogeneity of disease-free survival (DFS) or in treatment effect according to ESR1 status. However, significant differences in DFS were observed for subsets based on a combination of ESR1 and HER2 status (P = 0.02). CONCLUSIONS: ESR1 aberrations were associated with HER2 status, Ki-67 labeling index and ER and PgR levels. When combined with HER2, ESR1 may be prognostic but should not be used for endocrine treatment selection in postmenopausal women with endocrine-responsive early breast cancer.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Carcinoma/diagnóstico , Carcinoma/tratamento farmacológico , Receptor alfa de Estrogênio/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/fisiologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma/metabolismo , Carcinoma/patologia , Estudos de Coortes , Dinamarca , Receptor alfa de Estrogênio/análise , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pós-Menopausa/genética , Pós-Menopausa/metabolismo , Valor Preditivo dos Testes , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
17.
J Surg Orthop Adv ; 21(3): 117-21, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23199937

RESUMO

Although introduced more than 20 years ago, endoscopic carpal tunnel release (ECTR) continues to generate debate and controversy among surgeons. This review examines a single surgeon's technique for ECTR over the past 13 years to better understand the effects of a surgeon's experience on outcomes. A retrospective review was performed on a case series of 129 patients ages 25 to 89 years old who underwent an ECTR at Duke University. Ninety-six percent of patients reported improvement in nerve symptoms. There were no nerve complications in the series. The billed cost of ECTR at Duke University was 9% less than standard open release and the average return to work by report by patients was 3 weeks. Previous recommendations against ECTR have focused on increased complication rates and cost, with no reported differences in long-term clinical outcomes. The results demonstrate increased success and lower complication rates for this series of patients. This may indicate a significant correlation between a surgeon's expertise and outcomes for ECTR.


Assuntos
Síndrome do Túnel Carpal/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Endoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
18.
J Surg Orthop Adv ; 21(4): 242-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23327850

RESUMO

Athletic patients with osteonecrosis of the femoral head have few desirable therapeutic options that preserve athletic ability. Because these patients are usually young and healthy, any procedure that avoids total hip arthroplasty would be most desirable. This study prospectively evaluated 15 patients (19 hips) who presented with an average age of 28.5 (range, 12 to 46) years and stages 2 (6/19), 3 (2/19), 4 (9/19), and 5 (2/19) of osteonecrosis of the femoral head. All patients were treated with free vascularized fibular autografting (FVFG) to the femoral head. Postoperative evaluations of pain symptoms and functional activity showed improvements in all patients. The average follow-up time was 8 years. Harris hip scores significantly increased from an average preoperative score of 75.3 to an average postoperative score of 94.8. Seventy-five percent of patients were able to return to their sport after recovery and all patients reported being satisfied with the procedure and would repeat their decision to have surgery. Three patients' hips were converted to arthroplasty at 3, 11, and 17 years post-FVFG. The results demonstrate that FVFG is a successful therapeutic treatment in athletes with osteonecrosis of the femoral head. It reduces pain, increases activity, and allows most patients to return to their sport, an achievement often not possible with other treatment options.


Assuntos
Necrose da Cabeça do Fêmur/cirurgia , Cabeça do Fêmur/cirurgia , Fíbula/transplante , Adolescente , Adulto , Idoso , Criança , Feminino , Necrose da Cabeça do Fêmur/diagnóstico por imagem , Necrose da Cabeça do Fêmur/reabilitação , Humanos , Pessoa de Meia-Idade , Radiografia , Recuperação de Função Fisiológica , Esportes , Transplante Autólogo , Adulto Jovem
19.
J Hand Surg Am ; 36(7): 1142-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21620585

RESUMO

PURPOSE: The purpose of this study was to investigate whether ambulatory surgery centers can deliver lower-cost care and to identify sources of those cost savings. METHODS: We performed a cost identification analysis of outpatient volar plating for closed distal radius fractures at a single academic medical center. Multiple costs and time measures were taken from an internal database of 130 consecutive patients and were compared by venue of treatment, either an inpatient facility or an ambulatory, stand-alone surgery facility. The relationships between total cost and operative time and multiple variables, including fracture severity, patient age, gender, comorbidities, use of bone graft, concurrent carpal tunnel release, and surgeon experience, were examined, using multivariate analysis and regression modeling to identify other cost drivers or explanatory variables. RESULTS: The mean operative cost was considerably greater at the inpatient facility ($7,640) than at the outpatient facility ($5,220). Cost drivers of this difference were anesthesia services, post-anesthesia care unit, and operating room costs. Total surgical time, nursing time, set-up, and operative times were 33%, 109%, 105%, and 35% longer, respectively, at the inpatient facility. There was no significant difference between facilities for the additional variables, and none of those variables independently affected cost or operative time. CONCLUSIONS: The only predictor of cost and time was facility type. This study supports the use of ambulatory stand-alone surgical facilities to achieve efficient resource utilization in the operative treatment of distal radius fractures. We also identified several specific costs and time measurements that differed between facilities, which can serve as potential targets for tertiary facilities to improve utilization. TYPE OF STUDY/LEVEL OF EVIDENCE: Economic and Decisional Analysis III.


Assuntos
Procedimentos Cirúrgicos Ambulatórios/economia , Redução de Custos , Custos Hospitalares , Hospitalização/economia , Fraturas do Rádio/cirurgia , Centros Médicos Acadêmicos , Procedimentos Cirúrgicos Ambulatórios/métodos , Análise de Variância , Análise Custo-Benefício , Feminino , Fixação Interna de Fraturas/economia , Fixação Interna de Fraturas/métodos , Custos de Cuidados de Saúde , Hospitalização/estatística & dados numéricos , Humanos , Tempo de Internação/economia , Modelos Lineares , Masculino , Análise Multivariada , North Carolina , Radiografia , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/economia , Estudos Retrospectivos , Traumatismos do Punho/diagnóstico por imagem , Traumatismos do Punho/economia , Traumatismos do Punho/cirurgia
20.
J Neurosci ; 29(39): 12220-8, 2009 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-19793980

RESUMO

Pavlovian cues for rewards become endowed with incentive salience, guiding "wanting" to their learned reward. Usually, cues are "wanted" only if their rewards have ever been "liked," but here we show that mesocorticolimbic systems can recompute "wanting" de novo by integrating novel physiological signals with a cue's preexisting associations to an outcome that lacked hedonic value. That is, a cue's incentive salience can be recomputed adaptively. We demonstrate that this recomputation is encoded in neural signals coursing through the ventral pallidum. Ventral pallidum neurons do not ordinarily fire vigorously to a cue that predicts the previously "disliked" taste of intense salt, although they do fire to a cue that predicts the taste of previously "liked" sucrose. Yet we show that neural firing rises dramatically to the salt cue immediately and selectively when that cue is encountered in a never-before-experienced state of physiological salt depletion. Crucially, robust neural firing to the salt cue occurred the first time it was encountered in the new depletion state (in cue-only extinction trials), even before its associated intense saltiness has ever been tasted as positively "liked" (salt taste had always been "disliked" before). The amplification of incentive salience did not require additional learning about the cue or the newly positive salt taste. Thus dynamic recomputation of cue-triggered "wanting" signals can occur in real time at the moment of cue re-encounter by combining previously learned Pavlovian associations with novel physiological information about a current state of specific appetite.


Assuntos
Biologia Computacional/métodos , Motivação , Potenciais de Ação/fisiologia , Animais , Condicionamento Clássico/fisiologia , Sinais (Psicologia) , Aprendizagem/fisiologia , Masculino , Rede Nervosa/fisiologia , Ratos , Ratos Sprague-Dawley , Recompensa
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA