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1.
Ethics Med Public Health ; 26: 100860, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36467267

RESUMO

Background and aims: Healthcare workers (HCWs) throughout the world have been exposed to economic and existential stress during the Covid-19 pandemic. The American Medical Association (AMA) has documented that increased healthcare burden correlates with increased stress, burnout, and psychological burden in HCWs. However, limits on personnel, time, and in person interactions make it challenging to assess mental health outcomes during a pandemic. This pilot study used virtual technology to efficiently assess these outcomes. Setting: Data were collected based on voluntary participation in the Coping with Covid-19 for Caregivers Survey created by AMA. The survey was sent out to approximately 300 participants who included local physicians, medical residents, medical students, and allied health professionals and students who attended a virtual Mental Health Summit. Methods: The AMA developed survey included questions about demographics, overall stress, fear of infection and transmission of the virus, perceived anxiety or depression due to Covid-19, work overload, childcare issues, and sense of meaning and purpose. The AMA allows for up to five additional questions to be added to their survey, therefore five questions regarding support service utilization, perseverance, and resilience during the Covid-19 pandemic, and two items to further understand students' areas of medical interest. The survey was administered using an online platform through the AMA. The data were analyzed using descriptive statistics. Results: There were 81 survey respondents. Based on the results of the survey, "high stress" was found in 52 (64%) participants. 66 (81%) were afraid (moderately or to a great extent) of exposure or transmission, 61 (75%) described high levels of anxiety or depression, and 67 (84%) noted work overload. Despite this increase in stress, most respondents (77%) said they were not likely to reduce their devoted hours to clinical care or research in the next 12 months, and 81% answered that they would not leave their practice or research within two years. Conclusion: Covid-19 has negatively affected the well-being of HCWs. This is a similar trend seen during other times of healthcare strain. Mental health support, work modulation, and various provisions should be explored as means to reduce Covid-19-related negative impacts. The use of an online summit and online data collection methods were appropriate for collecting data on the impact of the Covid-19 pandemic on mental health. This pilot study supports the larger scale implementation of this technology for health informatics research.

2.
Psychopharmacology (Berl) ; 232(4): 745-54, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25138647

RESUMO

RATIONALE: Cocaine addiction is characterized by alternating cycles of abstinence and relapse and loss of control of drug use despite severe negative life consequences associated with its abuse. OBJECTIVE: The objective of the present study was to elucidate critical neural circuits involved in individual vulnerabilities to resumption of cocaine self-administration following prolonged abstinence. METHODS: The subjects were three female rhesus monkeys in prolonged abstinence following a long history of cocaine self-administration. Initial experiments examined the effects of acute cocaine administration (0.3 mg/kg, IV) on functional brain connectivity across the whole brain and in specific brain networks related to behavioral control using functional magnetic resonance imaging in fully conscious subjects. Subsequently, these subjects were allowed to resume cocaine self-administration to determine whether loss of basal connectivity within specific brain networks predicted the magnitude of resumption of cocaine intake following prolonged abstinence. RESULTS: Acute cocaine administration robustly decreased global functional connectivity and selectively impaired top-down prefrontal circuits that control behavior, while sparing connectivity of striatal areas within limbic circuits. Importantly, impaired connectivity between prefrontal and striatal areas during abstinence predicted cocaine intake when these subjects were provided renewed access to cocaine. CONCLUSIONS: Based on these findings, loss of prefrontal to striatal functional connectivity may be a critical mechanism underlying the negative downward spiral of cycles of abstinence and relapse that characterizes cocaine addiction.


Assuntos
Cocaína/administração & dosagem , Corpo Estriado/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Animais , Transtornos Relacionados ao Uso de Cocaína/fisiopatologia , Corpo Estriado/patologia , Feminino , Macaca mulatta , Imageamento por Ressonância Magnética , Vias Neurais/efeitos dos fármacos , Córtex Pré-Frontal/patologia , Autoadministração , Fatores Sexuais , Síndrome de Abstinência a Substâncias/patologia
3.
Horm Behav ; 61(2): 181-90, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22197270

RESUMO

3,4-methylenedioxymethamphetamine (MDMA) is a substituted phenethylamine that is widely abused as the street drug "ecstasy". Racemic MDMA (S,R(+/-)-MDMA) and its stereoisomers elicit complex spectrums of psychobiological, neurochemical, and hormonal effects. In this regard, recent findings demonstrated that S,R(+/-)-MDMA and its stereoisomer R(-)-MDMA elicit increases in striatal extracellular serotonin levels and plasma levels of the hormone prolactin in rhesus monkeys. In the present mechanistic study, we evaluated the role of the serotonin transporter and the 5-HT(2A) receptor in S,R(+/-)-MDMA- and R(-)-MDMA-elicited prolactin secretion in rhesus monkeys through concurrent microdialysis and plasma analysis determinations and drug interaction experiments. Concurrent neurochemical and hormone determinations showed a strong positive temporal correlation between serotonin release and prolactin secretion. Consistent with their distinct mechanisms of action and previous studies showing that the serotonin transporter inhibitor fluoxetine attenuates the behavioral and neurochemical effects of S,R(+/-)-MDMA, pretreatment with fluoxetine attenuated serotonin release elicited by either S,R(+/-)-MDMA or R(-)-MDMA. As hypothesized, at a dose that had no significant effects on circulating prolactin levels when administered alone, fluoxetine also attenuated prolactin secretion elicited by S,R(+/-)-MDMA. In contrast, combined pretreatment with both fluoxetine and the selective 5-HT(2A) receptor antagonist M100907 was required to attenuate prolactin secretion elicited by R(-)-MDMA, suggesting that this stereoisomer of S,R(+/-)-MDMA elicits prolactin secretion through both serotonin release and direct agonism of 5-HT(2A) receptors. Accordingly, these findings inform our understanding of the neuropharmacology of both S,R(+/-)-MDMA and R(-)-MDMA and the regulation of prolactin secretion.


Assuntos
Alucinógenos/farmacologia , N-Metil-3,4-Metilenodioxianfetamina/sangue , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Prolactina/sangue , Prolactina/metabolismo , Serotoninérgicos/farmacologia , Animais , Feminino , Fluorbenzenos/farmacologia , Fluoxetina/farmacologia , Alucinógenos/sangue , Macaca mulatta , Microdiálise , Piperidinas/farmacologia , Serotoninérgicos/sangue , Antagonistas da Serotonina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacocinética , Estereoisomerismo , Fatores de Tempo
4.
J Pharmacol Exp Ther ; 334(2): 642-50, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20466795

RESUMO

3,4-Methylenedioxymethamphetamine (MDMA) is an amphetamine derivative that elicits complex biological effects in humans. One plausible mechanism for this phenomenon is that racemic MDMA is composed of two stereoisomers that exhibit qualitatively different pharmacological effects. In support of this, studies have shown that R(-)-MDMA tends to have hallucinogen-like effects, whereas S(+)-MDMA tends to have psychomotor stimulant-like effects. However, relatively little is known about whether these stereoisomers engender different endocrine and neurochemical effects. In the present study, the endocrine and neurochemical effects of each stereoisomer and the racemate were assessed in four rhesus monkeys after intravenous delivery at doses (1-3 mg/kg) that approximated voluntary self-administration by rhesus monkeys and human recreational users. Specifically, fluorescence-based enzyme-linked immunosorbent assay was used to assess plasma prolactin concentrations, and in vivo microdialysis was used to assess extracellular dopamine and serotonin concentrations in the dorsal striatum. R(-)-MDMA, but not S(+)-MDMA, significantly increased plasma prolactin levels and the effects of S,R(+/-)-MDMA were intermediate to each of its component stereoisomers. Although S(+)-MDMA did not alter prolactin levels, it did significantly increase extracellular serotonin concentrations. In addition, S(+)-MDMA, but not R(-)-MDMA, significantly increased dopamine concentrations. Furthermore, as in the prolactin experiment, the effects of the racemate were intermediate to each of the stereoisomers. These studies demonstrate the stereoisomers of MDMA engender qualitatively different endocrine and neurochemical effects, strengthening the inference that differences in these stereoisomers might be the mechanism producing the complex biological effects of the racemic mixture of MDMA in humans.


Assuntos
Estimulantes do Sistema Nervoso Central/farmacologia , Corpo Estriado/efeitos dos fármacos , Dopamina/metabolismo , Alucinógenos/farmacologia , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Prolactina/metabolismo , Serotonina/metabolismo , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Estimulantes do Sistema Nervoso Central/química , Corpo Estriado/metabolismo , Espaço Extracelular/metabolismo , Feminino , Alucinógenos/química , Ácido Homovanílico/metabolismo , Macaca mulatta , Microdiálise , N-Metil-3,4-Metilenodioxianfetamina/química , Estereoisomerismo , Relação Estrutura-Atividade
5.
J Pharmacol Exp Ther ; 331(2): 717-23, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19684254

RESUMO

3,4-Methylenedioxymethamphetamine (MDMA) is a substituted phenethylamine more commonly known as the drug of abuse "ecstasy." The acute and persistent neurochemical effects of MDMA in the mice are distinct from those in other species. MDMA shares biological effects with both amphetamine-type stimulants and mescaline-type hallucinogens, which may be attributable to distinct effects of its two enantiomers, both of which are active in vivo. In this regard, among the substituted phenethylamines, R(-)-enantiomers tend to have hallucinogen-like effects, whereas S(+)-enantiomers tend to have stimulant-like effects. In the present study, mice were trained to discriminate S(+)- or R(-)-MDMA from vehicle. Drug substitution tests were then undertaken with the structurally similar phenethylamine dopamine/norepinephrine releaser S(+)-amphetamine, the structurally dissimilar tropane nonselective monoamine reuptake inhibitor cocaine, the structurally similar phenethylamine 5-hydroxytryptamine (5-HT)(2A) agonist 2,5-dimethoxy-4-(n)-propylthiophenethylamine (2C-T-7), and the structurally dissimilar mixed action tryptamine 5-HT(2A) agonist/monoamine reuptake inhibitor N,N-dipropyltryptamine (DPT). S(+)-amphetamine fully substituted in the S(+)-MDMA-treated animals but did not substitute for the R(-)-MDMA cue. 2C-T-7 fully substituted in the R(-)-MDMA-trained animals but did not substitute for the S(+)-MDMA cue. Cocaine and DPT substituted for both training drugs, but whereas cocaine was more potent in S(+)-MDMA-trained mice, DPT was more potent in R(-)-MDMA-trained mice. These data suggest that qualitative differences in the discriminative stimulus effects of each stereoisomer of MDMA exist in mice and further our understanding of the complex nature of the interoceptive effects of MDMA.


Assuntos
Estimulantes do Sistema Nervoso Central/farmacologia , Discriminação Psicológica/efeitos dos fármacos , Alucinógenos/farmacologia , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Anfetaminas/farmacologia , Animais , Cocaína/farmacologia , Condicionamento Operante/efeitos dos fármacos , Aprendizagem por Discriminação/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Camundongos , N-Metil-3,4-Metilenodioxianfetamina/química , Fenetilaminas/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Estereoisomerismo , Triptaminas/farmacologia
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