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1.
Nature ; 615(7954): 866-873, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36991187

RESUMO

The urban peoples of the Swahili coast traded across eastern Africa and the Indian Ocean and were among the first practitioners of Islam among sub-Saharan people1,2. The extent to which these early interactions between Africans and non-Africans were accompanied by genetic exchange remains unknown. Here we report ancient DNA data for 80 individuals from 6 medieval and early modern (AD 1250-1800) coastal towns and an inland town after AD 1650. More than half of the DNA of many of the individuals from coastal towns originates from primarily female ancestors from Africa, with a large proportion-and occasionally more than half-of the DNA coming from Asian ancestors. The Asian ancestry includes components associated with Persia and India, with 80-90% of the Asian DNA originating from Persian men. Peoples of African and Asian origins began to mix by about AD 1000, coinciding with the large-scale adoption of Islam. Before about AD 1500, the Southwest Asian ancestry was mainly Persian-related, consistent with the narrative of the Kilwa Chronicle, the oldest history told by people of the Swahili coast3. After this time, the sources of DNA became increasingly Arabian, consistent with evidence of growing interactions with southern Arabia4. Subsequent interactions with Asian and African people further changed the ancestry of present-day people of the Swahili coast in relation to the medieval individuals whose DNA we sequenced.


Assuntos
População Africana , Asiático , Genética Populacional , Feminino , Humanos , Masculino , População Africana/genética , Asiático/genética , História Medieval , Oceano Índico , Tanzânia , Quênia , Moçambique , Comores , História do Século XV , História do Século XVI , História do Século XVII , Índia/etnologia , Pérsia/etnologia , Arábia/etnologia , DNA Antigo/análise
2.
N Engl J Med ; 389(3): 215-227, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37467497

RESUMO

BACKGROUND: Natural history studies have correlated serotype-specific anti-capsular polysaccharide (CPS) IgG in newborns with a reduced risk of group B streptococcal disease. A hexavalent CPS-cross-reactive material 197 glycoconjugate vaccine (GBS6) is being developed as a maternal vaccine to prevent invasive group B streptococcus in young infants. METHODS: In an ongoing phase 2, placebo-controlled trial involving pregnant women, we assessed the safety and immunogenicity of a single dose of various GBS6 formulations and analyzed maternally transferred anti-CPS antibodies. In a parallel seroepidemiologic study that was conducted in the same population, we assessed serotype-specific anti-CPS IgG concentrations that were associated with a reduced risk of invasive disease among newborns through 89 days of age to define putative protective thresholds. RESULTS: Naturally acquired anti-CPS IgG concentrations were associated with a reduced risk of disease among infants in the seroepidemiologic study. IgG thresholds that were determined to be associated with 75 to 95% reductions in the risk of disease were 0.184 to 0.827 µg per milliliter. No GBS6-associated safety signals were observed among the mothers or infants. The incidence of adverse events and of serious adverse events were similar across the trial groups for both mothers and infants; more local reactions were observed in the groups that received GBS6 containing aluminum phosphate. Among the infants, the most common serious adverse events were minor congenital anomalies (umbilical hernia and congenital dermal melanocytosis). GBS6 induced maternal antibody responses to all serotypes, with maternal-to-infant antibody ratios of approximately 0.4 to 1.3, depending on the dose. The percentage of infants with anti-CPS IgG concentrations above 0.184 µg per milliliter varied according to serotype and formulation, with 57 to 97% of the infants having a seroresponse to the most immunogenic formulation. CONCLUSIONS: GBS6 elicited anti-CPS antibodies against group B streptococcus in pregnant women that were transferred to infants at levels associated with a reduced risk of invasive group B streptococcal disease. (Funded by Pfizer and the Bill and Melinda Gates Foundation; C1091002 ClinicalTrials.gov number, NCT03765073.).


Assuntos
Infecções Estreptocócicas , Vacinas Estreptocócicas , Streptococcus agalactiae , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Anticorpos Antibacterianos , Imunoglobulina G , Estudos Soroepidemiológicos , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/prevenção & controle , Vacinas Combinadas/administração & dosagem , Vacinas Combinadas/efeitos adversos , Vacinas Combinadas/imunologia , Vacinas Combinadas/uso terapêutico , Vacinas Conjugadas/administração & dosagem , Vacinas Conjugadas/efeitos adversos , Vacinas Conjugadas/imunologia , Vacinas Conjugadas/uso terapêutico , Vacinas Estreptocócicas/administração & dosagem , Vacinas Estreptocócicas/efeitos adversos , Vacinas Estreptocócicas/imunologia , Vacinas Estreptocócicas/uso terapêutico , Imunidade Materno-Adquirida/imunologia
3.
J Neurosci ; 44(20)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38561227

RESUMO

Human frontocentral event-related potentials (FC-ERPs) are ubiquitous neural correlates of cognition and control, but their generating multiscale mechanisms remain mostly unknown. We used the Human Neocortical Neurosolver's biophysical model of a canonical neocortical circuit under exogenous thalamic and cortical drive to simulate the cell and circuit mechanisms underpinning the P2, N2, and P3 features of the FC-ERP observed after Stop-Signals in the Stop-Signal task (SST; N = 234 humans, 137 female). We demonstrate that a sequence of simulated external thalamocortical and corticocortical drives can produce the FC-ERP, similar to what has been shown for primary sensory cortices. We used this model of the FC-ERP to examine likely circuit-mechanisms underlying FC-ERP features that distinguish between successful and failed action-stopping. We also tested their adherence to the predictions of the horse-race model of the SST, with specific hypotheses motivated by theoretical links between the P3 and Stop process. These simulations revealed that a difference in P3 onset between successful and failed Stops is most likely due to a later arrival of thalamocortical drive in failed Stops, rather than, for example, a difference in the effective strength of the input. In contrast, the same model predicted that early thalamocortical drives underpinning the P2 and N2 differed in both strength and timing across stopping accuracy conditions. Overall, this model generates novel testable predictions of the thalamocortical dynamics underlying FC-ERP generation during action-stopping. Moreover, it provides a detailed cellular and circuit-level interpretation that supports links between these macroscale signatures and predictions of the behavioral race model.


Assuntos
Potenciais Evocados , Modelos Neurológicos , Humanos , Feminino , Masculino , Potenciais Evocados/fisiologia , Adulto , Adulto Jovem , Lobo Frontal/fisiologia , Rede Nervosa/fisiologia , Tálamo/fisiologia , Eletroencefalografia , Desempenho Psicomotor/fisiologia
4.
PLoS Comput Biol ; 20(2): e1011108, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38408099

RESUMO

Biophysically detailed neural models are a powerful technique to study neural dynamics in health and disease with a growing number of established and openly available models. A major challenge in the use of such models is that parameter inference is an inherently difficult and unsolved problem. Identifying unique parameter distributions that can account for observed neural dynamics, and differences across experimental conditions, is essential to their meaningful use. Recently, simulation based inference (SBI) has been proposed as an approach to perform Bayesian inference to estimate parameters in detailed neural models. SBI overcomes the challenge of not having access to a likelihood function, which has severely limited inference methods in such models, by leveraging advances in deep learning to perform density estimation. While the substantial methodological advancements offered by SBI are promising, their use in large scale biophysically detailed models is challenging and methods for doing so have not been established, particularly when inferring parameters that can account for time series waveforms. We provide guidelines and considerations on how SBI can be applied to estimate time series waveforms in biophysically detailed neural models starting with a simplified example and extending to specific applications to common MEG/EEG waveforms using the the large scale neural modeling framework of the Human Neocortical Neurosolver. Specifically, we describe how to estimate and compare results from example oscillatory and event related potential simulations. We also describe how diagnostics can be used to assess the quality and uniqueness of the posterior estimates. The methods described provide a principled foundation to guide future applications of SBI in a wide variety of applications that use detailed models to study neural dynamics.


Assuntos
Teorema de Bayes , Humanos , Simulação por Computador
5.
PLoS Genet ; 18(6): e1010230, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35709096

RESUMO

Central nervous system-expressed long non-coding RNAs (lncRNAs) are often located in the genome close to protein coding genes involved in transcriptional control. Such lncRNA-protein coding gene pairs are frequently temporally and spatially co-expressed in the nervous system and are predicted to act together to regulate neuronal development and function. Although some of these lncRNAs also bind and modulate the activity of the encoded transcription factors, the regulatory mechanisms controlling co-expression of neighbouring lncRNA-protein coding genes remain unclear. Here, we used high resolution NG Capture-C to map the cis-regulatory interaction landscape of the key neuro-developmental Paupar-Pax6 lncRNA-mRNA locus. The results define chromatin architecture changes associated with high Paupar-Pax6 expression in neurons and identify both promoter selective as well as shared cis-regulatory-promoter interactions involved in regulating Paupar-Pax6 co-expression. We discovered that the TCF7L2 transcription factor, a regulator of chromatin architecture and major effector of the Wnt signalling pathway, binds to a subset of these candidate cis-regulatory elements to coordinate Paupar and Pax6 co-expression. We describe distinct roles for Paupar in Pax6 expression control and show that the Paupar DNA locus contains a TCF7L2 bound transcriptional silencer whilst the Paupar transcript can act as an activator of Pax6. Our work provides important insights into the chromatin interactions, signalling pathways and transcription factors controlling co-expression of adjacent lncRNAs and protein coding genes in the brain.


Assuntos
RNA Longo não Codificante , Cromatina/genética , Neurônios/metabolismo , Fator de Transcrição PAX6/genética , Fator de Transcrição PAX6/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Fatores de Transcrição/genética
6.
Artigo em Inglês | MEDLINE | ID: mdl-38391112

RESUMO

OBJECTIVES: To assess the impact on patient outcomes of the spondyloarthritis (SpA) and inflammatory bowel disease (IBD) multidisciplinary team (MDT) meetings in a large university hospital. METHODS: A single-centre retrospective observational case-note review was conducted assessing the outcome of all 226 cases discussed at the SpA-IBD MDT meetings in a large UK university hospital between 2017-2022. RESULTS: A total of 226 patients were discussed. It was deemed that 97% of MDT meetings helped to improve communication between teams, and 100% were educational. A total of 57% of discussions led to an instant change of disease management, while 40% of discussions resulted in a treatment plan that avoided the use of dual advanced therapy. This improved patient safety by reducing immunosuppression. The MDT meetings were highly cost and time efficient; 125 referrals between specialists were avoided, and in 51 cases there was a significant chance of reducing future drug costs. A timely investigation or appointment was arranged following 50% of MDT discussions, helping to clarify the diagnosis and optimise patient care. 9% of meetings enabled drugs to be prescribed to patients that are not yet licenced for the other speciality, thereby improving treatment options available in the management of complex cases. CONCLUSION: The MDT meetings have been beneficial for patients, the clinical team and the institution. This approach might be considered by other rheumatology and gastroenterology departments.

7.
Psychooncology ; 33(1): e6243, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37946565

RESUMO

OBJECTIVE: To undertake an economic evaluation of a telehealth psychological support intervention for patients with primary brain tumor (PBT). METHODS: A within-trial cost-utility analysis over 6 months was performed comparing a tailored telehealth-psychological support intervention with standard care (SC) in a randomized control trial. Data were sourced from the Telehealth Making Sense of Brain Tumor (Tele-MAST) trial survey data, project records, and administrative healthcare claims. Quality-adjusted life years (QALYs) were calculated based on the EuroQol-5D-5L. Non-parametric bootstrapping with 2000 iterations was used to determine sampling uncertainty. Multiple imputation was used for handling missing data. RESULTS: The Tele-MAST trial included 82 participants and was conducted in Queensland, Australia during 2018-2021. When all healthcare claims were included, the incremental cost savings from Tele-MAST were -AU$4,327 (95% CI: -$8637, -$18) while incremental QALY gains were small at 0.03 (95% CI: -0.02, 0.08). The likelihood of Tele-MAST being cost-effective versus SC was 87% at a willingness-to-pay threshold of AU$50,000 per QALY gain. When psychological-related healthcare costs were included only, the incremental cost per QALY gain was AU$10,685 (95% CI: dominant, $24,566) and net monetary benefits were AU$534 (95% CI: $466, $602) with a 65% likelihood of the intervention being cost-effective. CONCLUSIONS: Based on this small randomized controlled trial, the Tele-MAST intervention is a cost-effective intervention for improving the quality of life of people with PBT in Australia. Patients receiving the intervention incurred significantly lower overall healthcare costs than patients in SC. There was no significant difference in costs incurred for psychological health services.


Assuntos
Neoplasias Encefálicas , Telemedicina , Humanos , Análise Custo-Benefício , Qualidade de Vida , Custos de Cuidados de Saúde , Neoplasias Encefálicas/terapia , Anos de Vida Ajustados por Qualidade de Vida
8.
Rapid Commun Mass Spectrom ; 38(15): e9775, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38807480

RESUMO

RATIONALE: Spironolactone is a steroidal drug prescribed for a variety of medical conditions and is extensively metabolized quickly after administration. Measurement of spironolactone and its metabolites remains challenging using mass spectrometry (MS) due to in-source fragmentation and relatively poor ionization using electrospray ionization. Therefore, improved methods of measurements are needed, particularly in the case of small sample volumes. METHODS: Girard's reagent P (GP) derivatization of spironolactone was employed to improve response and provide an MS-based solution to the measurement of spironolactone and its metabolites. We performed ultra-high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UHPLC-ESI-MS/MS) and ion mobility spectrometry (IMS)-high-resolution mass spectrometry (HRMS) to fully characterize the GP derivatization products. Analytes were studied in positive ionization mode, and MS/MS was performed using nonresonance and resonance excitation collision-induced dissociation. RESULTS: We observed the successful GP derivatization of spironolactone and its metabolites using authentic chemical standards. A signal enhancement of 1-2 orders of magnitude was observed for GP-derivatized versions of spironolactone and its metabolites. Further, GP derivatization eliminated in-source fragmentation. Finally, we performed GP derivatization and ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) in a small volume of murine serum (20 µL) from spironolactone-treated and control animals and observed multiple spironolactone metabolites only in the spironolactone-treated group. CONCLUSIONS: GP derivatization was proven to have advantageous mass spectral performance (e.g., limiting in-source fragmentation, enhancing signals, and eliminating isobaric analytes) for spironolactone and its metabolites. This work and the detailed characterization using ultra-high-performance liquid chromatography-high-resolution tandem mass spectrometry (UHPLC-HRMS/MS) and IMS serve as the foundation for future developments in reaction optimization and/or quantitative assay development.


Assuntos
Espectrometria de Mobilidade Iônica , Espectrometria de Massas por Ionização por Electrospray , Espironolactona , Espectrometria de Massas em Tandem , Espironolactona/química , Espironolactona/sangue , Espironolactona/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Animais , Espectrometria de Massas em Tandem/métodos , Camundongos , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Mobilidade Iônica/métodos , Masculino
9.
Environ Sci Technol ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329046

RESUMO

Labile carbon (C) continuously delivered from the rhizosphere profoundly affects terrestrial nitrogen (N) cycling. However, nitrous oxide (N2O) and dinitrogen (N2) production in agricultural soils in the presence of continuous root C exudation with applied N remains poorly understood. We conducted an incubation experiment using artificial roots to continuously deliver small-dose labile C combined with 15N tracers to investigate N2O and N2 emissions in agricultural soils with pH and organic C (SOC) gradients. A significantly negative exponential relationship existed between N2O and N2 emissions under continuous C exudation. Increasing soil pH significantly promoted N2 emissions while reducing N2O emissions. Higher SOC further promoted N2 emissions in alkaline soils. Native soil-N (versus fertilizer-N) was the main source of N2O (average 67%) and N2 (average 80%) emissions across all tested soils. Our study revealed the overlooked high N2 emissions, mainly derived from native soil-N and strengthened by increasing soil pH, under relatively real-world conditions with continuous root C exudation. This highlights the important role of N2O and N2 production from native soil-N in terrestrial N cycling when there is a continuous C supply (e.g., plant-root exudate) and helps mitigate emissions and constrain global budgets of the two concerned nitrogenous gases.

10.
J Urban Health ; 101(2): 252-261, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38514599

RESUMO

The COVID-19 pandemic introduced additional health challenges for people who use substances (PWUS) amid the overdose crisis. Numerous harm reduction services, including supervised consumption sites (SCS) across Canada, faced shutdowns and reduced operating capacity in order to comply with public health measures. Mobile Overdose Response Services (MORS) are novel overdose prevention technologies that allow those who are unable to access alternative means of harm reduction to consume substances under the virtual supervision of a trained operator. Here, we examine the role of MORS in the context of the COVID-19 pandemic. A total of 59 semi-structured interviews were conducted with the following key interest groups: PWUS, healthcare providers, harm reduction workers, MORS operators, and the general public. Inductive thematic analysis informed by grounded theory was used to identify major themes pertaining to the perception of MORS. As the pandemic shifted the public focus away from harm reduction, many participants viewed MORS as an acceptable strategy to reduce the harms associated with solitary substance and alleviate the sense of isolation driven by social distancing measures. While the pandemic may have increased the utility of MORS, concerns surrounding personal privacy and confidentiality remained. Overall, MORS were perceived as a useful adjunct service to address the unmet needs PWUS during the pandemic and beyond.


Assuntos
COVID-19 , Overdose de Drogas , Redução do Dano , Pesquisa Qualitativa , Humanos , COVID-19/prevenção & controle , COVID-19/epidemiologia , Overdose de Drogas/prevenção & controle , Canadá , Feminino , SARS-CoV-2 , Masculino , Adulto , Unidades Móveis de Saúde , Entrevistas como Assunto , Pandemias , Pessoa de Meia-Idade , Pessoal de Saúde/psicologia
11.
Brain Cogn ; 177: 106164, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38670050

RESUMO

Recent work has found that the presence of transient, oscillatory burst-like events, particularly within the beta band (15-29 Hz), is more closely tied to disease state and behavior across species than traditional electroencephalography (EEG) power metrics. This study sought to examine whether features of beta events over frontoparietal electrodes were associated with early life stress (ELS) and the related clinical presentation. Eighteen adults with documented ELS (n = 18; ELS + ) and eighteen adults without documented ELS (n = 18; ELS-) completed eyes-closed resting state EEG as part of their participation in a larger childhood stress study. The rate, power, duration, and frequency span of transient oscillatory events were calculated within the beta band at five frontoparietal electrodes. ELS variables were positively associated with beta event rate at Fp2 and beta event duration at Pz, in that greater ELS was associated with higher resting rates and longer durations. These beta event characteristics were used to successfully distinguish between ELS + and ELS- groups. In an independent clinical dataset (n = 25), beta event power at Pz was positively correlated with ELS. Beta events deserve ongoing investigation as a potential disease marker of ELS and subsequent psychiatric treatment outcomes.


Assuntos
Ritmo beta , Eletroencefalografia , Estresse Psicológico , Humanos , Feminino , Adulto , Masculino , Ritmo beta/fisiologia , Estresse Psicológico/fisiopatologia , Eletroencefalografia/métodos , Lobo Frontal/fisiopatologia , Lobo Parietal/fisiopatologia , Adulto Jovem , Pessoa de Meia-Idade
12.
Palliat Med ; : 2692163241261211, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916277

RESUMO

BACKGROUND: Family caregivers of people with high-grade glioma often report high rates of psychological distress, which has been attributed to the unique aspects of the disease and onerous care demands. Clinical practice guidelines advocate for caregiver support from diagnosis through to end-of-life and bereavement. Yet, research has identified that caregivers' support needs are often overlooked. AIM: To explore caregivers' experiences of psychological support and perceptions of what constitutes optimal psychological support for caregivers in the context of high-grade glioma. DESIGN: Qualitative study involving semi-structured interviews with data analysed using reflexive thematic analysis. SETTING/PARTICIPANTS: Eighteen current (n = 11) and bereaved (n = 7) family caregivers (73% female, aged 33-69 years) of adults with high-grade glioma participated. Interviews explored caregivers' perceptions of psychological support. RESULTS: Two major themes were generated. The first theme, 'It was never about me', reflected caregivers prioritise for people with high-grade glioma to be well supported despite experiencing their own unmet psychological support needs. The second theme, 'Continuous, coordinated and personalised support', highlighted the importance of timely and tailored interventions addressing caregivers' practical, educational and emotional support needs throughout the illness journey. CONCLUSIONS: Caregivers commonly prioritise the support needs of people with high-grade gliomas; yet, have their own distinct needs that vary throughout the illness. Primary care providers have a potential role in facilitating timely access to palliative care, practical support and brain tumour-specific psychological support to meet caregivers' diverse needs across the care continuum in the context of high-grade glioma.

13.
J Community Health ; 49(2): 286-295, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37932627

RESUMO

Cigarette smoking significantly contributes to preventable illness, death, and economic costs. Despite overall reduction in national smoking rates, disparities persist between demographic groups and geographic regions. While some studies have explored urban-rural differences in smoking prevalence, gaps exist in understanding localized patterns. This study focuses on examining smoking rates and related factors at the census tract level in McLennan County, Texas, a county that contains a mixture of urban, peri-urban, and rural areas. This study uses census tract level aggregate sociodemographic, smoking, and health-related data from the American Community Survey and the PLACES Project City Health Dashboard. Geospatial analyses mapped co-occurrence of high prevalence of smoking, mental and physical distress, and co-occurrence of lower routine medical check-ups, household income, and education. Multiple linear regression modeled associations between smoking and sociodemographic, and health-related factors. Geospatial analyses identified census tracts with co-occurring high prevalence of smoking, mental and physical distress, and co-occurrence of lower routine medical check-ups, household income, and education level in McLennan County. Regression analyses identified that smoking rates were positively correlated with frequent physical distress (p < 0.0001) and negatively correlated with the proportion of routine medical check-ups (p < 0.0001) and the proportion living in poverty (p = 0.0002). This study found significant variations in smoking rates, physical and mental distress, medical check-ups, and sociodemographic factors between neighboring census tracts which geospatial analyses examining larger geographic units may have overlooked. Future research should focus on obtaining individual-level and community-level data to develop more targeted interventions sensitive to specific community contexts.


Assuntos
Setor Censitário , Fumar Cigarros , Humanos , Texas/epidemiologia , Fatores Sociodemográficos , Pobreza
14.
Harm Reduct J ; 21(1): 31, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317194

RESUMO

BACKGROUND: In response to the exacerbated rates of morbidity and mortality associated with the overlapping overdose and COVID-19 epidemics, novel strategies have been developed, implemented, operationalized and scaled to reduce the harms resulting from this crisis. Since the emergence of mobile overdose response services (MORS), two strategies have aimed to help reduce the mortality associated with acute overdose including staffed hotline-based services and unstaffed timer-based services. In this article, we aim to gather the perspectives of various key interest groups on these technologies to determine which might best support service users. METHODS: Forty-seven participants from various interested groups including people who use substances who have and have not used MORS, healthcare workers, family members, harm reduction employees and MORS operators participated in semi-structured interviews. Transcripts were coded and analyzed using a thematic analysis approach. RESULTS: Four major themes emerged regarding participant perspectives on the differences between services, namely differences in connection, perceived safety, privacy and accessibility, alongside features that are recommended for MORS in the future. CONCLUSIONS: Overall, participants noted that individuals who use substances vary in their desire for connection during a substance use session offered by hotline and timer-based service modalities. Participants perceived hotline-based approaches to be more reliable and thus potentially safer than their timer-based counterparts but noted that access to technology is a limitation of both approaches.


Assuntos
Overdose de Drogas , Epidemias , Aplicativos Móveis , Humanos , Linhas Diretas , Overdose de Drogas/epidemiologia , Pesquisa Qualitativa , Redução do Dano
15.
Harm Reduct J ; 21(1): 141, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39068494

RESUMO

BACKGROUND: Supervised consumption sites (SCS) and overdose prevention sites (OPS) have been implemented across Canada to mitigate harms associated with illicit substance use. Despite their successes, they still contend with challenges that limit their accessibility and uptake. Overdose response hotlines and apps are novel virtual technologies reminiscent of informal "spotting" methods that may address some of the limitations. Here, we strove to qualitatively examine the factors that may encourage or deter utilization of these virtual services and SCS. METHODS: A total of 52 participants across Canada were recruited using convenience and snowball sampling methods. These included people with lived and living experience of substance use, family members of people with lived experience, healthcare providers, community harm reduction workers, and virtual harm reduction operators. Semi-structured telephone interviews were conducted and inductive thematic analysis was performed to identify the themes pertaining to SCS and virtual harm reduction. RESULTS: Participants viewed overdose response hotline and apps as an opportunity to consume substances without being hindered by logistical barriers (e.g., wait times), fear of law enforcement, invasion of privacy, and more. They also noted that these virtual services provided more flexibility for clients who opt for routes of consumption that are not supported by SCS, such as smoking. Overall, SCS was perceived to be better than virtual services at facilitating social connection, providing additional resources/referrals, as well as prompt response to overdose. CONCLUSION: In sum, participants viewed SCS and virtual services as filling different needs and gaps. This study adds to a growing body of literature which informs how virtual harm reduction services can serve as useful adjunct to more standard harm reduction methods.


Assuntos
Overdose de Drogas , Redução do Dano , Linhas Diretas , Humanos , Canadá , Feminino , Overdose de Drogas/prevenção & controle , Masculino , Adulto , Programas de Troca de Agulhas , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Pessoa de Meia-Idade , Pesquisa Qualitativa , Aplicativos Móveis , Telemedicina
16.
Harm Reduct J ; 21(1): 28, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38308262

RESUMO

INTRODUCTION: Unregulated supply of fentanyl and adulterants continues to drive the overdose crisis. Mobile Overdose Response Services (MORS) are novel technologies that offer virtual supervised consumption to minimize the risk of fatal overdose for those who are unable to access other forms of harm reduction. However, as newly implemented services, they are also faced with numerous limitations. The aim of this study was to examine the facilitators and barriers to the adoption of MORS in Canada. METHODS: A total of 64 semi-structured interviews were conducted between November 2021 and April 2022. Participants consisted of people who use substances (PWUS), family members of PWUS, health care professionals, harm reduction workers, MORS operators, and members of the general public. Inductive thematic analysis was used to identify the major themes and subthemes. RESULTS: Respondents revealed that MORS facilitated a safe, anonymous, and nonjudgmental environment for PWUS to seek harm reduction and other necessary support. It also created a new sense of purpose for operators to positively contribute to the community. Further advertising and promotional efforts were deemed important to increase its awareness. However, barriers to MORS implementation included concerns regarding privacy/confidentiality, uncertainty of funding, and compassion fatigue among the operators. CONCLUSION: Although MORS were generally viewed as a useful addition to the currently existing harm reduction services, it's important to monitor and tackle these barriers by engaging the perspectives of key interest groups.


Assuntos
Overdose de Drogas , Opinião Pública , Humanos , Canadá , Overdose de Drogas/prevenção & controle , Pesquisa Qualitativa , Fentanila , Redução do Dano
17.
J Neurosci ; 42(22): 4470-4487, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35477903

RESUMO

The cortico-basal ganglia circuit is needed to suppress prepotent actions and to facilitate controlled behavior. Under conditions of response conflict, the frontal cortex and subthalamic nucleus (STN) exhibit increased spiking and theta band power, which are linked to adaptive regulation of behavioral output. The electrophysiological mechanisms underlying these neural signatures of impulse control remain poorly understood. To address this lacuna, we constructed a novel large-scale, biophysically principled model of the subthalamopallidal (STN-globus pallidus externus) network and examined the mechanisms that modulate theta power and spiking in response to cortical input. Simulations confirmed that theta power does not emerge from intrinsic network dynamics but is robustly elicited in response to cortical input as burst events representing action selection dynamics. Rhythmic burst events of multiple cortical populations, representing a state of conflict where cortical motor plans vacillate in the theta range, led to prolonged STN theta and increased spiking, consistent with empirical literature. Notably, theta band signaling required NMDA, but not AMPA, currents, which were in turn related to a triphasic STN response characterized by spiking, silence, and bursting periods. Finally, theta band resonance was also strongly modulated by architectural connectivity, with maximal theta arising when multiple cortical populations project to individual STN "conflict detector" units because of an NMDA-dependent supralinear response. Our results provide insights into the biophysical principles and architectural constraints that give rise to STN dynamics during response conflict, and how their disruption can lead to impulsivity and compulsivity.SIGNIFICANCE STATEMENT The subthalamic nucleus exhibits theta band power modulation related to cognitive control over motor actions during conditions of response conflict. However, the mechanisms of such dynamics are not understood. Here we developed a novel biophysically detailed and data-constrained large-scale model of the subthalamopallidal network, and examined the impacts of cellular and network architectural properties that give rise to theta dynamics. Our investigations implicate an important role for NMDA receptors and cortico-subthalamic nucleus topographical connectivities in theta power modulation.


Assuntos
Córtex Motor , Núcleo Subtalâmico , Gânglios da Base , Globo Pálido , Córtex Motor/fisiologia , N-Metilaspartato , Núcleo Subtalâmico/fisiologia
18.
Neuroimage ; 274: 120133, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37094626

RESUMO

STUDY OBJECTIVES: Sleep slow wave activity, as measured using EEG delta power (<4 Hz), undergoes significant changes throughout development, mirroring changes in brain function and anatomy. Yet, age-dependent variations in the characteristics of individual slow waves have not been thoroughly investigated. Here we aimed at characterizing individual slow wave properties such as origin, synchronization, and cortical propagation at the transition between childhood and adulthood. METHODS: We analyzed overnight high-density (256 electrodes) EEG recordings of healthy typically developing children (N = 21, 10.3 ± 1.5 years old) and young healthy adults (N = 18, 31.1 ± 4.4 years old). All recordings were preprocessed to reduce artifacts, and NREM slow waves were detected and characterized using validated algorithms. The threshold for statistical significance was set at p = 0.05. RESULTS: The slow waves of children were larger and steeper, but less widespread than those of adults. Moreover, they tended to mainly originate from and spread over more posterior brain areas. Relative to those of adults, the slow waves of children also displayed a tendency to more strongly involve and originate from the right than the left hemisphere. The separate analysis of slow waves characterized by high and low synchronization efficiency showed that these waves undergo partially distinct maturation patterns, consistent with their possible dependence on different generation and synchronization mechanisms. CONCLUSIONS: Changes in slow wave origin, synchronization, and propagation at the transition between childhood and adulthood are consistent with known modifications in cortico-cortical and subcortico-cortical brain connectivity. In this light, changes in slow-wave properties may provide a valuable yardstick to assess, track, and interpret physiological and pathological development.


Assuntos
Ondas Encefálicas , Neocórtex , Adulto , Humanos , Criança , Eletroencefalografia , Sono/fisiologia , Ondas Encefálicas/fisiologia
19.
Neuroimage ; 274: 120112, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37105338

RESUMO

Adolescence is a stage of development characterized by neurodevelopmental specialization of cognitive processes. In particular, working memory continues to improve through adolescence, with increases in response accuracy and decreases in response latency continuing well into the twenties. Human electroencephalogram (EEG) studies indicate that gamma oscillations (35-65 Hz) during the working memory delay period support the maintenance of mnemonic information guiding subsequent goal-driven behavior, which decrease in power with development. Importantly, recent electrophysiological studies have shown that gamma events, more so than sustained activity, may underlie working memory maintenance during the delay period. However, developmental differences in gamma events during working memory have not been studied. Here, we used EEG in conjunction with a novel spectral event processing approach to investigate age-related differences in transient gamma band activity during a memory guided saccade (MGS) task in 164 10- to 30-year-olds. Total gamma power was found to significantly decrease through adolescence, replicating prior findings. Results from the spectral event pipeline showed age-related decreases in the mean power of gamma events and trial-by-trial power variability across both the delay period and fixation epochs of the MGS task. In addition, we found that while event number decreased with age during the fixation period, the developmental decrease during the delay period was more dramatic, resulting in an increase in event spiking from fixation to delay in adolescence but not adulthood. While average power of the transient gamma events was found to mediate age-related differences in total gamma power in the fixation and delay periods, the number of gamma events was related to total power in only the delay period, suggesting that the power of gamma events may underlie the sustained gamma activity seen in EEG literature while the number of events may directly support age-related improvements in working memory maintenance. Our findings provide compelling new evidence for mechanistic changes in neural processing characterized by refinements in neural function as behavior becomes optimized in adulthood.


Assuntos
Eletroencefalografia , Memória de Curto Prazo , Humanos , Adolescente , Memória de Curto Prazo/fisiologia , Tempo de Reação/fisiologia , Eletroencefalografia/métodos
20.
Am J Obstet Gynecol ; 228(2): 161-177, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36027953

RESUMO

OBJECTIVE: This sequential, prospective meta-analysis sought to identify risk factors among pregnant and postpartum women with COVID-19 for adverse outcomes related to disease severity, maternal morbidities, neonatal mortality and morbidity, and adverse birth outcomes. DATA SOURCES: We prospectively invited study investigators to join the sequential, prospective meta-analysis via professional research networks beginning in March 2020. STUDY ELIGIBILITY CRITERIA: Eligible studies included those recruiting at least 25 consecutive cases of COVID-19 in pregnancy within a defined catchment area. METHODS: We included individual patient data from 21 participating studies. Data quality was assessed, and harmonized variables for risk factors and outcomes were constructed. Duplicate cases were removed. Pooled estimates for the absolute and relative risk of adverse outcomes comparing those with and without each risk factor were generated using a 2-stage meta-analysis. RESULTS: We collected data from 33 countries and territories, including 21,977 cases of SARS-CoV-2 infection in pregnancy or postpartum. We found that women with comorbidities (preexisting diabetes mellitus, hypertension, cardiovascular disease) vs those without were at higher risk for COVID-19 severity and adverse pregnancy outcomes (fetal death, preterm birth, low birthweight). Participants with COVID-19 and HIV were 1.74 times (95% confidence interval, 1.12-2.71) more likely to be admitted to the intensive care unit. Pregnant women who were underweight before pregnancy were at higher risk of intensive care unit admission (relative risk, 5.53; 95% confidence interval, 2.27-13.44), ventilation (relative risk, 9.36; 95% confidence interval, 3.87-22.63), and pregnancy-related death (relative risk, 14.10; 95% confidence interval, 2.83-70.36). Prepregnancy obesity was also a risk factor for severe COVID-19 outcomes including intensive care unit admission (relative risk, 1.81; 95% confidence interval, 1.26-2.60), ventilation (relative risk, 2.05; 95% confidence interval, 1.20-3.51), any critical care (relative risk, 1.89; 95% confidence interval, 1.28-2.77), and pneumonia (relative risk, 1.66; 95% confidence interval, 1.18-2.33). Anemic pregnant women with COVID-19 also had increased risk of intensive care unit admission (relative risk, 1.63; 95% confidence interval, 1.25-2.11) and death (relative risk, 2.36; 95% confidence interval, 1.15-4.81). CONCLUSION: We found that pregnant women with comorbidities including diabetes mellitus, hypertension, and cardiovascular disease were at increased risk for severe COVID-19-related outcomes, maternal morbidities, and adverse birth outcomes. We also identified several less commonly known risk factors, including HIV infection, prepregnancy underweight, and anemia. Although pregnant women are already considered a high-risk population, special priority for prevention and treatment should be given to pregnant women with these additional risk factors.


Assuntos
COVID-19 , Doenças Cardiovasculares , Infecções por HIV , Hipertensão , Complicações na Gravidez , Nascimento Prematuro , Gravidez , Recém-Nascido , Feminino , Humanos , COVID-19/epidemiologia , Nascimento Prematuro/epidemiologia , Estudos Prospectivos , Magreza , SARS-CoV-2 , Resultado da Gravidez/epidemiologia , Fatores de Risco , Complicações na Gravidez/epidemiologia , Período Pós-Parto
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