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1.
J Integr Neurosci ; 23(4): 83, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38682231

RESUMO

BACKGROUND: Much of the existing animal literature on the devaluation task suggests that prior repeated exposure to drugs of abuse during adulthood can impair goal-directed action, but the literature on human drug users is mixed. Also, the initiation of drug use often occurs during adolescence, but examinations of the effects of drug exposure during adolescence on behavior in the devaluation task are lacking. METHODS: We examined whether repeated exposure during adolescence to amphetamine (3 mg/kg injections every-other day from post-natal day 27-45) or ketamine (twice daily 30 mg/kg injections from post-natal day 35-44) would impair behavior in a devaluation test when tested drug-free in adulthood. Rats were trained to press a left lever with a steady cue-light above it for one reinforcer and a right lever with a flashing cue-light above it for a different reinforcer. We tested whether any impairments in goal-directed action could be overcome by compensation between strategies by giving rats information based on lever-location and cue-lights during the test that was either congruent (allowing compensation) or incongruent (preventing compensation between strategies) with the configurations during training. RESULTS: Our results provided no evidence for impairment of goal-directed action during adulthood after adolescent amphetamine or ketamine exposure. CONCLUSIONS: We discuss possible reasons for this discrepancy with the prior literature, including (1) the age of exposure and (2) the pattern in the previous literature that most previous demonstrations of drug exposure impairing devaluation in laboratory animals may be attributed to either drug-associated cues present in the testing environment and/or accelerated habit learning in tasks that predispose laboratory animals towards habit formation with extended training (with training procedures that should resist the formation of habits in the current experiment). However, additional research is needed to examine the effects of these factors, as well a potential role for the particular doses and washout periods to determine the cause of our finding of no devaluation impairment after drug exposure.


Assuntos
Anfetamina , Ketamina , Animais , Ketamina/farmacologia , Ketamina/administração & dosagem , Anfetamina/farmacologia , Anfetamina/administração & dosagem , Masculino , Ratos , Condicionamento Operante/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/farmacologia , Estimulantes do Sistema Nervoso Central/administração & dosagem , Ratos Long-Evans , Comportamento Animal/efeitos dos fármacos , Fatores Etários , Sinais (Psicologia)
2.
Trials ; 25(1): 88, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38279184

RESUMO

BACKGROUND: Respiratory viral illness (RVI)-e.g., influenza, COVID-19-is a serious threat in long-term care (LTC) facilities. Standard infection control measures are suboptimal in LTC facilities because of residents' cognitive impairments, care needs, and susceptibility to loneliness and mental illness. Further, LTC residents living with high degrees of frailty who contract RVIs often develop the so-called atypical symptoms (e.g., delirium, worse mobility) instead of typical cough and fever, delaying infection diagnosis and treatment. Although far-UVC (222 nm) light devices have shown potent antiviral activity in vitro, clinical efficacy remains unproven. METHODS: Following a study to assay acceptability at each site, this multicenter, double-blinded, cluster-randomized, placebo-controlled trial aims to assess whether far-UVC light devices impact the incidence of RVIs in LTC facilities. Neighborhoods within LTC facilities are randomized to receive far-UVC light devices (222 nm) or identical placebo light devices that emit only visible spectrum light (400-700 nm) in common areas. All residents are monitored for RVIs using both a standard screening protocol and a novel screening protocol that target atypical symptoms. The 3-year incidence of RVIs will be compared using intention-to-treat analysis. A cost-consequence analysis will follow. DISCUSSION: This trial aims to inform decisions about whether to implement far-UVC light in LTC facilities for RVI prevention. The trial design features align with this pragmatic intent. Appropriate additional ethical protections have been implemented to mitigate participant vulnerabilities that arise from conducting this study. Knowledge dissemination will be supported through media engagement, peer-reviewed presentations, and publications. TRIAL REGISTRATION: ClinicalTrials.gov NCT05084898. October 20, 2021.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Assistência de Longa Duração , Instalações de Saúde , Instituições de Cuidados Especializados de Enfermagem , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
3.
Artigo em Inglês | MEDLINE | ID: mdl-36483428

RESUMO

Objective: To identify preventable factors that contribute to the cross transmission of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) to patients in healthcare facilities. Design: A case-control study was conducted among inpatients on a coronavirus disease 2019 (COVID-19) outbreak unit. Setting: This study was conducted in a medical-surgical unit of a tertiary-care hospital in Nova Scotia in May 2021. Patients: Patients hospitalized on the unit for at least 12 hours and healthcare workers (HCW) working on the unit within 2 weeks of outbreak declaration were included. Methods: Risk factors for SARS-CoV-2 infection were analyzed using simple and multiple logistic regression. Whole-genome sequencing (WGS) was performed to identify SARS-CoV-2 strain relatedness. Network analysis was used to describe patient accommodation. Results: SARS-CoV-2 infections were identified in 21 patients (29.6%) and 11 HCWs (6.6%). WGS data revealed 4 distinct clades of related sequences. Several factors likely contributed to the outbreak, including failure to identify SARS-CoV-2, a largely incomplete or unvaccinated population, and patient wandering behaviors. The most significant risk factor for SARS-CoV-2 infection was room sharing with an infectious patient, which was the only factor that remained statistically significant following multivariate analysis (odds ratio [OR], 9.2l; 95% confidence interval [CI], 2.04-41.67; P = .004). Conclusions: This outbreak likely resulted from admission of 2 patients with COVID-19, with subsequent transmissions to 17 patients and 11 staff. WGS and bioinformatics analyses were critical to identifying previously unrecognized nosocomial transmissions of SARS-CoV-2. This study supports strategies to reduce nosocomial transmissions of SARS-CoV-2, such as single-patient rooms, promotion of COVID-19 vaccination, and infection prevention and control measures including management of wandering behaviors.

4.
J Neurosci ; 41(49): 10080-10090, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34716230

RESUMO

Accumulating evidence in the past decade implicates histone-modifying enzymes, such as class I histone deacetylases (HDACs), in learning and memory and, recently, habit formation. However, it is unclear whether HDACs play roles in complex cognitive function. To address this issue, we examined the role of dorsal striatal HDAC5, a class II HDAC, in reward-guided decision-making and associated neural encoding in rats. We first injected adeno-associated virus to overexpress a nuclear-localized HDAC5 in dorsal striatum (DS). We then recorded neural correlates from dorsolateral striatum (DLS) as rats performed two reward-guided choice tasks, in which we manipulated either the size of or delay to reward. During these tasks, rats first learned which of two options led to the better reward and then reversed those contingencies in a second block of trials. We found that rats with HDAC5 overexpression in DS responded faster and chose higher value reward more often during the first block of trials but were less able to reverse those contingencies in the second block of trials. At the neural level, HDAC5 overexpression in DS elevated and reduced the number of cells in DLS that increased firing to stimuli and reward, respectively, and shifted encoding toward cues that predicted more immediate reward. These results suggest that the HDAC5 overexpression in DS contributes to inflexible decision-making, demonstrating a role of histone-modifying enzymes in complex cognitive function.SIGNIFICANCE STATEMENT HDACs are important for learning and habit formation. Here, we expanded on these functions and found that overexpression of HDAC5 produced faster and more automatic behavior, and related changes in dorsolateral striatal neural firing in rats performing a value-based decision-making task. These results implicate HDAC5 as a potential therapeutic target for psychiatric conditions that impair decision-making and executive function.


Assuntos
Corpo Estriado/metabolismo , Tomada de Decisões/fisiologia , Histona Desacetilases/metabolismo , Animais , Feminino , Masculino , Ratos , Ratos Sprague-Dawley , Recompensa
5.
Pharmacol Biochem Behav ; 200: 173087, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33309825

RESUMO

Methamphetamine (Meth) seeking progressively increases after cessation from drug self-administration (incubation of Meth craving). We have previously shown that both dorsomedial and dorsolateral striatum (DMS and DLS) play critical roles in this incubation in male rats. Moreover, our recent anatomical tracing study examined afferent projections into DMS and demonstrated a novel role of projections from anterior intralaminar nucleus of thalamus (AIT) to DMS in incubation of Meth craving in male rats. Here we investigated projection-specific activation of afferent glutamate projections into DLS associated with incubated Meth seeking in female rats. We trained female rats to self-administer Meth (6-h/d for 10 d). On abstinence day 12, we injected cholera toxin subunit B (CTb, a retrograde tracer) unilaterally into DLS. On abstinence day 26, we tested rats for relapse to Meth seeking and measured Fos (a neuronal activity marker), and double-labeling of CTb and Fos in anterior cingulate cortex, anterior insula cortex, orbitofrontal cortex, basolateral amygdala, AIT, and parafascicular nuclei of thalamus. We observed neuronal activation in both cortical and thalamic regions associated with incubated Meth seeking. At the circuit level, AIT➔DLS projections were strongly activated, followed by other corticostriatal projections. Overall our results suggest that AIT to DLS may play a role in Meth seeking after prolonged abstinence in female rats.


Assuntos
Estimulantes do Sistema Nervoso Central/farmacologia , Corpo Estriado/metabolismo , Comportamento de Procura de Droga/efeitos dos fármacos , Núcleos Intralaminares do Tálamo/metabolismo , Metanfetamina/farmacologia , Transtornos Relacionados ao Uso de Anfetaminas/metabolismo , Animais , Córtex Cerebral/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Fissura/efeitos dos fármacos , Feminino , Núcleos Intralaminares do Tálamo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Autoadministração/métodos , Tálamo/efeitos dos fármacos , Tálamo/metabolismo
6.
Addict Biol ; 26(2): e12927, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32570285

RESUMO

One of the main challenges in treating opioid-use disorders is relapse during abstinence, triggered by re-exposure to drug-associated cues. Previous studies have demonstrated that drug-seeking in rats progressively increases over time during withdrawal (incubation of drug craving). Here, we used male rats and examined neural mechanisms underlying incubation of craving to oxycodone, a commonly abused prescription opioid, and we focused on orbitofrontal cortex (OFC), a brain region previously implicated in incubation of heroin craving. We first used neuronal activity marker Fos and measured neuronal activation in OFC (ventral and lateral OFC) associated with day-1 and day-15 relapse tests. Next, we determined the effect of pharmacological reversible inactivation of OFC on incubated oxycodone seeking on withdrawal day 15. Finally, we determined the effect of reversible inactivation of OFC on nonincubated oxycodone seeking on withdrawal day 1. We found that lever presses during relapse tests were higher on withdrawal day 15 than on withdrawal day 1 (incubation of oxycodone craving). Incubation of oxycodone craving is accompanied with a time-dependent increase of Fos protein expression in both ventral and lateral OFC. Lastly, OFC inactivation decreased oxycodone seeking on withdrawal day 15 but had no effect on withdrawal day 1. Together with the previous heroin study, results here show that OFC plays a critical role in incubation of opioid craving.


Assuntos
Fissura/efeitos dos fármacos , Comportamento de Procura de Droga/efeitos dos fármacos , Oxicodona/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Animais , Genes fos/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley
7.
J Clin Microbiol ; 58(7)2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32321781

RESUMO

Compared to the standard two-tiered testing (STTT) algorithm for Lyme disease serology using an enzyme immunoassay (EIA) followed by Western blotting, data from the United States suggest that a modified two-tiered testing (MTTT) algorithm employing two EIAs has improved sensitivity to detect early localized Borrelia burgdorferi infections without compromising specificity. From 2011 to 2014, in the Canadian province of Nova Scotia, where Lyme disease is hyperendemic, sera submitted for Lyme disease testing were subjected to a whole-cell EIA, followed by C6 EIA and subsequently IgM and/or IgG immunoblots on sera with EIA-positive or equivocal results. Here, we evaluate the effectiveness of the MTTT algorithm compared to the STTT approach in a Nova Scotian population. Retrospective chart reviews were performed on patients testing positive with the whole-cell and C6 EIAs (i.e., the MTTT algorithm). Patients were classified as having Lyme disease if they had a positive STTT result, a negative STTT result but symptoms consistent with Lyme disease, or evidence of seroconversion on paired specimens. Of the 10,253 specimens tested for Lyme disease serology, 9,806 (95.6%) were negative. Of 447 patients who tested positive, 271 charts were available for review, and 227 were classified as patients with Lyme disease. The MTTT algorithm detected 25% more early infections with a specificity of 99.56% (99.41 to 99.68%) compared to the STTT. These are the first Canadian data to show that serology using a whole-cell sonicate EIA followed by a C6 EIA (MTTT) had improved sensitivity for detecting early B. burgdorferi infection with specificity similar to that of two-tiered testing using Western blots.


Assuntos
Borrelia burgdorferi , Doença de Lyme , Algoritmos , Anticorpos Antibacterianos , Humanos , Técnicas Imunoenzimáticas , Imunoglobulina M , Doença de Lyme/diagnóstico , Nova Escócia , Estudos Retrospectivos , Sensibilidade e Especificidade , Testes Sorológicos
8.
Brain Behav ; 9(9): e01378, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31364821

RESUMO

BACKGROUND: Methamphetamine (Meth) seeking progressively increases after withdrawal (incubation of Meth craving). We previously demonstrated a role of anterior intralaminar nucleus of thalamus (AIT) to dorsomedial striatum (DMS) projections in this incubation. Here, we examined molecular alterations in DMS and AIT neurons activated (identified by neuronal activity marker Fos) during "incubated" Meth-seeking relapse test after prolonged withdrawal. METHODS: We trained male rats to self-administer Meth or saline (control condition) for 10 days (6 hr/day). Using fluorescence-activated cell sorting, we examined gene expression in Fos-positive (activated during a 2-hr relapse test) and Fos-negative (nonactivated) DMS and AIT neurons. RESULTS: In DMS, we found increased mRNA expressions of immediate early genes (IEGs) (Arc, Egr1, Npas4, Fosb), Trkb, glutamate receptors subunits (Gria3, Grin1, Grin2b, Grm1), and epigenetic enzymes (Hdac3, Hdac5, Crebbp) in Fos-positive neurons, compared with Fos-negative neurons. In AIT, we found that fewer genes (Egr1, Fosb, TrkB, Grin1, and Hdac5) exhibited increased mRNA expression in Fos-positive neurons. Unexpectedly, in both brain regions, gene alterations described above also occurred in drug-naïve saline self-administration control rats. CONCLUSIONS: These results demonstrated that transcriptional regulations in Fos-positive neurons activated during the relapse tests are brain region-specific but are not uniquely associated with drug exposure during the self-administration training.


Assuntos
Corpo Estriado/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Metanfetamina/administração & dosagem , Proteínas Proto-Oncogênicas c-fos/metabolismo , Síndrome de Abstinência a Substâncias/genética , Síndrome de Abstinência a Substâncias/metabolismo , Tálamo/metabolismo , Animais , Corpo Estriado/efeitos dos fármacos , Fissura/fisiologia , Modelos Animais de Doenças , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-fos/genética , Ratos , Ratos Sprague-Dawley , Autoadministração , Tálamo/efeitos dos fármacos
9.
Appetite ; 136: 160-172, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30721744

RESUMO

The current study sought to understand how long-term exposure to diets high in saturated fat and refined sugar affected impulsive choice behavior, discrimination abilities, incentive motivation, food preferences, and liking of fat and sugar in male rats. The results showed that 8 weeks of dietary exposure impaired impulsive choice behavior; rats exposed to diets high in processed fat or sugar were more sensitive to changes in delay, a marker of impulsivity. For the high-fat group, these deficits in impulsive choice may stem from poor time discrimination, as their performance was impaired on a temporal discrimination task. The high-fat group also showed reduced magnitude sensitivity in the impulsive choice task, and they earned fewer rewards during lever press training indicating potentially reduced incentive motivation. The high-fat group also developed a preference for high-fat foods compared to the chow and high-sugar group who both preferred sugar. In contrast, dietary exposure did not alter the liking of fat or sugar as measured by a taste reactivity task. Together, the results suggest that the alterations in impulsive choice, time discrimination, incentive motivation, and food preferences induced by consumption of a high-fat diet could make individuals vulnerable to overeating, and thus obesity.


Assuntos
Comportamento de Escolha/efeitos dos fármacos , Gorduras na Dieta/farmacologia , Sacarose Alimentar/farmacologia , Preferências Alimentares/efeitos dos fármacos , Comportamento Impulsivo/efeitos dos fármacos , Motivação/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Dieta Hiperlipídica/métodos , Aprendizagem por Discriminação/efeitos dos fármacos , Masculino , Modelos Animais , Ratos , Ratos Sprague-Dawley , Recompensa
10.
Emerg Infect Dis ; 24(1): 165-166, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29260666

RESUMO

In Canada, Hansen disease (leprosy) is rare and not considered in diagnoses for nonimmigrant patients. We report Mycobacterium leprae infection in a Canadian man whose sole travel was to Florida, USA. The M. leprae isolate was identified as armadillo-associated genotype 3I-2-v1. Travelers to the southern United States should avoid contact with armadillos.


Assuntos
Hanseníase/diagnóstico , Hanseníase/epidemiologia , Idoso , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Canadá , Dapsona/administração & dosagem , Dapsona/uso terapêutico , Quimioterapia Combinada , Florida , Humanos , Hansenostáticos/administração & dosagem , Hansenostáticos/uso terapêutico , Hanseníase/microbiologia , Masculino , Mycobacterium leprae , Ofloxacino/administração & dosagem , Ofloxacino/uso terapêutico , Rifampina/administração & dosagem , Rifampina/uso terapêutico , Viagem
11.
Int J Radiat Oncol Biol Phys ; 99(1): 90-93, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28816169

RESUMO

PURPOSE: To determine the impact on long-term survival from the addition of brachytherapy to external beam radiation therapy (EBRT) in patients with prostate cancer. METHODS AND MATERIALS: Between 1992 and 1997, 104 men with cT2-3, surgically staged node-negative prostate cancer were randomized to receive either EBRT (40 Gy/20 fractions) with iridium implant (35 Gy/48 hours) or EBRT alone (66 Gy/33 fractions) to the prostate. According to T stage, Gleason score, and prostate-specific antigen level, 60% of patients had high-risk disease. Substantial improvements in biochemical control at 8 years have previously been reported. Additional follow-up was collected on deaths and metastases. RESULTS: Median follow-up was 14 years. Five patients were lost to follow-up. All other patients have been followed a minimum of 13 years. There have been 75 deaths, including 21 from prostate cancer and 25 from second cancers. No patients developing a second cancer have died from prostate cancer. There was no difference in overall survival between the 2 treatment groups: 34 deaths (67%) in the implant arm and 41 (77%) in the EBRT arm (hazard ratio [HR] 1.00, 95% confidence interval [CI] 0.63-1.59). Similarly, there was no difference in prostate cancer-specific deaths: 9 (18%) patients in the implant arm compared with 12 (23%) in the EBRT arm (HR 0.79, 95% CI 0.34-1.87). There was no statistically significant difference in the number of patients developing metastatic disease: 10 (20%) in the implant arm and 15 (28%) in the EBRT arm (HR 0.70, 95% CI 0.32-1.57). Improvements in biochemical control were maintained (HR 0.53, 95% CI 0.31-0.88). CONCLUSIONS: Despite a dramatic reduction of biochemical recurrence rates, the addition of iridium implant to EBRT did not translate into improved overall survival or prostate cancer-specific survival.


Assuntos
Braquiterapia/métodos , Radioisótopos de Irídio/uso terapêutico , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/radioterapia , Causas de Morte , Seguimentos , Humanos , Masculino , Segunda Neoplasia Primária/mortalidade , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
13.
J Clin Oncol ; 23(6): 1192-9, 2005 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-15718316

RESUMO

PURPOSE: To determine if iridium implant (IM) and external-beam radiation therapy (EBRT) is better than standard EBRT in locally advanced prostate cancer. METHODS: Patients with T2 and T3 prostate cancer with no evidence of metastatic disease were randomly assigned to EBRT of 66 Gy in 33 fractions during 6.5 weeks or to IM of 35 Gy delivered to the prostate during 48 hours plus EBRT of 40 Gy in 20 fractions during 4 weeks. The primary outcome consisted of biochemical or clinical failure (BCF). BCF was defined by biochemical failure, clinical failure, or death as a result of prostate cancer. Secondary outcomes included 2-year postradiation biopsy positivity, toxicity, and survival. RESULTS: Between 1992 and 1997, 51 patients were randomly assigned to receive IM plus EBRT, and 53 patients were randomly assigned to receive EBRT alone. The median follow-up was 8.2 years. In the IM plus EBRT arm, 17 patients (29%) experienced BCF compared with 33 patients (61%) in the EBRT arm (hazard ratio, 0.42; P = .0024). Eighty-seven patients (84%) had a postradiation biopsy; 10 (24%) of 42 in the IM plus EBRT arm had biopsy positivity compared with 23 (51%) of 45 in the EBRT arm (odds ratio, 0.30; P = .015). Overall survival was 94% in the IM plus EBRT arm versus 92% in the EBRT arm. CONCLUSION: The combination of IM plus EBRT was superior to EBRT alone for BCF and postradiation biopsy. This trial provides evidence that higher doses of radiation delivered in a shorter duration result in better local as well as biochemical control in locally advanced prostrate cancer.


Assuntos
Adenocarcinoma/radioterapia , Braquiterapia , Irídio/uso terapêutico , Neoplasias da Próstata/radioterapia , Adenocarcinoma/mortalidade , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/mortalidade , Dosagem Radioterapêutica , Radioterapia Conformacional
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