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INTRODUCTION: Autistic young people and/or those with attention deficit hyperactivity disorder (ADHD) who have co-occurring mental health conditions experience significant challenges when transitioning from child and adolescent mental health services (CAMHS) to adult mental health services (AMHS). However, barriers and facilitators to this service transition are poorly understood for this population. This scoping review aims to synthesise the available evidence on barriers and enablers to the transition from CAMHS to AMHS for autistic young people and/or those with ADHD. METHODS AND ANALYSIS: Arksey and O'Malley's six-step framework for scoping reviews will be used. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist will guide the reporting of this review. Electronic databases of Medline, PsycINFO, CINAHL, Scopus, ProQuest Central and Google Scholar will be searched for relevant articles published in English with no date limitations. Title, abstract and full-text screening will be completed by two independent reviewers. Studies will be eligible for inclusion if the article focuses on (1) adolescents and/or young people (aged 18-24) with a primary diagnosis of autism spectrum disorder and/or ADHD (population) and (2) describes factors associated with service or care transitions (concept) (3) from CAMHS to AMHS (context). Study quality will be evaluated using the Standard Quality Assessment Criteria for Evaluating Primary Research Papers from a Variety of Fields. Data describing the factors that enable or inhibit the transition from CAMHS to AMHS will be extracted and synthesised using the Bronfenbrenner's social ecological model as a framework for organising and reporting results. ETHICS AND DISSEMINATION: Ethics approval is not required. Findings will be disseminated via peer-reviewed publications and presented at conferences. TRIAL REGISTRATION NUMBER: https://doi.org/10.17605/OSF.IO/BZPQF.
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Transtorno do Deficit de Atenção com Hiperatividade , Serviços de Saúde Mental , Transição para Assistência do Adulto , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Adolescente , Serviços de Saúde Mental/organização & administração , Criança , Projetos de Pesquisa , Transtorno Autístico/terapia , Acessibilidade aos Serviços de Saúde , Transtorno do Espectro Autista/terapia , Literatura de Revisão como Assunto , AdultoRESUMO
Nerve sheath tumors (NSTs) are well-recognized primary nervous system tumors, but there is relatively limited information in dogs including comparison of NSTs in different anatomical locations. This retrospective study describes the clinical features and outcomes in a group of dogs with NSTs affecting the cranial nerves or spinal nerves. Thirty dogs were included, 25 with a presumptive diagnosis and five confirmed by histopathologic analysis. Seven dogs also had cytology of tumor samples, which were supportive of the NST diagnosis in four. Eight dogs had cranial nerve-associated NSTs, with six involving the trigeminal nerve. Twenty-two dogs had spinal nerve-associated NSTs including 13 invading the spinal canal and nine peripheral to the spinal canal, with the majority affecting nerves or nerve roots of the brachial plexus. The prognosis was poor, with dogs being euthanized eventually because of disease progression. Among dogs alive 1 week after diagnosis, the median survival time was 4 months but ranged from 2 weeks to >2 years. While there was a broad overlap between NST locations, survival was generally longer for dogs without spinal canal or intracranial involvement. The results expand available information on NSTs in dogs but should be interpreted with caution given the small number of dogs with a definitive diagnosis. Further investigation is warranted to determine how tumor location, invasiveness, and treatments pursued impact outcome.
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A cell committed to proliferation must reshape its metabolism to enable robust yet balanced production of building blocks for the assembly of proteins, lipids, nucleic acids, and other macromolecules, from which two functional daughter cells can be produced. The metabolic remodeling associated with proliferation is orchestrated by a number of pro-proliferative signaling nodes, which include phosphatidylinositol-3 kinase (PI3K), the RAS family of small GTPases, and transcription factor c-myc In metazoan cells, these signals are activated in a paracrine manner via growth factor-mediated activation of receptor (or receptor-associated) tyrosine kinases. Such stimuli are limited in duration and therefore allow the metabolism of target cells to return to the resting state once the proliferation demands have been satisfied. Cancer cells acquire activating genetic alterations within common pro-proliferative signaling nodes. These alterations lock cellular nutrient uptake and utilization into a perpetual progrowth state, leading to the aberrant accumulation and spread of cancer cells.
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While differential antibody responses SARS-CoV-2 in patients with inflammatory bowel disease (IBD) receiving infliximab and vedolizumab are well-characterized, the immune pathways underlying these differences remain unknown. Prior to COVID-19 vaccine development, we screened 235 patients with IBD receiving biological therapy for antibodies to SARS-CoV-2 and measured serum cytokines. In seropositive patients, we prospectively collected clinical data. We found a cytokine signature in patients receiving vedolizumab who are seropositive compared with seronegative for SARS-CoV-2 antibodies that may be linked to repeated SARS-CoV-2 infections. However, there were no differences between seropositive and seronegative patients receiving infliximab. In this single-center cohort of patients with IBD with anti-SARS-CoV-2 antibodies at the onset of the COVID-19 pandemic, and therefore without influence of vaccination, there is a cytokine signature in patients receiving vedolizumab but not infliximab. These findings lay the groundwork for further studies on immune consequences of viral infection in patients with IBD, which is postulated to evolve from aberrant host-microbe responses.
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COVID-19 , Doenças Inflamatórias Intestinais , Humanos , SARS-CoV-2 , Vacinas contra COVID-19 , Infliximab/uso terapêutico , Pandemias , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Antivirais , Citocinas , Doenças Inflamatórias Intestinais/tratamento farmacológicoRESUMO
Despite the well-known benefits of physical activity, less than half of adults aged 55-75 years participate in sufficient physical activity. Short bouts of vigorous intermittent lifestyle physical activity (VILPA) accumulated throughout the day can contribute toward the recommended volume of physical activity. A rich characterization of the barriers and facilitators to participation in VILPA is needed to develop targeted interventions. This scoping review aimed to identify barriers and facilitators to participation in different components of VILPA in adults aged 55-75 years, and to map barriers and facilitators to the Theoretical Domains Framework. Within the 18 eligible studies, the most prevalent barriers were related to a person's skills, environmental context, and social influences. Most facilitators were related to a person's goals, social influences, and environmental context. Interventions to promote VILPA should test the effectiveness of behavioral change measures related to the unique barriers and facilitators in this age group.
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Exercício Físico , Estilo de Vida , Humanos , Idoso , Pessoa de Meia-Idade , Exercício Físico/psicologia , Masculino , FemininoRESUMO
Introduction: The key to understanding the COVID-19 correlates of protection is assessing vaccine-induced immunity in different demographic groups. Young people are at a lower risk of COVID-19 mortality, females are at a lower risk than males, and females often generate stronger immune responses to vaccination. Methods: We studied immune responses to two doses of BNT162b2 Pfizer COVID-19 vaccine in an adolescent cohort (n = 34, ages 12-16), an age group previously shown to elicit significantly greater immune responses to the same vaccine than young adults. Adolescents were studied with the aim of comparing their response to BNT162b2 to that of adults; and to assess the impacts of other factors such as sex, ongoing SARS-CoV-2 infection in schools, and prior exposure to endemic coronaviruses that circulate at high levels in young people. At the same time, we were able to evaluate immune responses to the co-administered live attenuated influenza vaccine. Blood samples from 34 adolescents taken before and after vaccination with COVID-19 and influenza vaccines were assayed for SARS-CoV-2-specific IgG and neutralising antibodies and cellular immunity specific for SARS-CoV-2 and endemic betacoronaviruses. The IgG targeting influenza lineages contained in the influenza vaccine were also assessed. Results: Robust neutralising responses were identified in previously infected adolescents after one dose, and two doses were required in infection-naïve adolescents. As previously demonstrated, total IgG responses to SARS-CoV-2 Spike were significantly higher among vaccinated adolescents than among adults (aged 32-52) who received the BNT162b2 vaccine (comparing infection-naïve, 49,696 vs. 33,339; p = 0.03; comparing SARS-CoV-2 previously infected, 743,691 vs. 269,985; p <0.0001) by the MSD v-plex assay. There was no evidence of a stronger vaccine-induced immunity in females compared than in males. Discussion: These findings may result from the introduction of novel mRNA vaccination platforms, generating patterns of immunity divergent from established trends and providing new insights into what might be protective following COVID-19 vaccination.
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COVID-19 , Vacinas contra Influenza , Feminino , Masculino , Adulto Jovem , Adolescente , Humanos , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , SARS-CoV-2 , Vacinas Atenuadas , Anticorpos Antivirais , Imunidade Celular , Imunoglobulina G , Reino Unido/epidemiologiaRESUMO
Lactate has long been considered a cellular waste product. However, we found that as extracellular lactate accumulates, it also enters the mitochondrial matrix and stimulates mitochondrial electron transport chain (ETC) activity. The resulting increase in mitochondrial ATP synthesis suppresses glycolysis and increases the utilization of pyruvate and/or alternative respiratory substrates. The ability of lactate to increase oxidative phosphorylation does not depend on its metabolism. Both L- and D-lactate are effective at enhancing ETC activity and suppressing glycolysis. Furthermore, the selective induction of mitochondrial oxidative phosphorylation by unmetabolized D-lactate reversibly suppressed aerobic glycolysis in both cancer cell lines and proliferating primary cells in an ATP-dependent manner and enabled cell growth on respiratory-dependent bioenergetic substrates. In primary T cells, D-lactate enhanced cell proliferation and effector function. Together, these findings demonstrate that lactate is a critical regulator of the ability of mitochondrial oxidative phosphorylation to suppress glucose fermentation.
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Metabolismo Energético , Ácido Láctico , Ácido Láctico/metabolismo , Transporte de Elétrons , Fosforilação Oxidativa , Glicólise/fisiologia , Trifosfato de Adenosina/metabolismoRESUMO
Hepatitis C virus infection (HCV) is prevalent in prisons. Therefore, effective prison HCV services are critical for HCV elimination programmes. We aimed to evaluate the efficacy of a regional HCV prison testing and treatment programme. Between July 2017 and June 2022, data were collected prospectively on HCV test offer and uptake rates, HCV Antibody (HCV-Ab) and HCV-RNA positivity, treatment starts and outcomes for new inmates incarcerated in three prisons. Rates of HCV-Ab and RNA positivity at reception, incidence of new HCV infections and reinfection following treatment were determined. From a total of 39,652 receptions, 33,028 (83.3%) were offered HCV testing and 20,394 (61.7%) completed testing. Including all receptions, 24.5% of tests (n = 4995) were HCV-Ab positive and 8.4% of tests (n = 1713) were HCV-RNA positive. When considering the first test for each individual (median age 34 years; 88.1% male), 14.8% (n = 1869) and 7.2% (n = 905) were HCV-Ab and HCV-RNA positive, respectively. The incidence of new HCV-Ab and RNA positivity was 5.1 and 3.3 per 100 person-years, respectively. Of 1145 HCV viraemic individuals, 18 died within 6 months and 150 were rapidly transferred out of area, leaving 977 individuals with outcomes. Of these, 835 (85.5%) received antivirals and 47 spontaneously cleared the infection, leaving 95 (9.7%) untreated. 607 (72.7%) achieved SVR. 95 patients had reinfection post-treatment (rate 10.1 cases per 100 person-years). Testing for HCV has increased in our prisons and the majority with viraemia are initiated on antiviral treatment. Reassuringly, a significant fall in frequency of HCV-RNA positivity at prison reception was observed suggesting progress towards HCV elimination.
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Hepatite C , Prisioneiros , Abuso de Substâncias por Via Intravenosa , Humanos , Masculino , Adulto , Feminino , Prisões , Reinfecção , Abuso de Substâncias por Via Intravenosa/epidemiologia , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepacivirus/genética , RNA , Inglaterra/epidemiologia , Anticorpos Anti-Hepatite C , Antivirais/uso terapêuticoRESUMO
Introduction: Family studies of antiviral immunity provide an opportunity to assess virus-specific immunity in infected and highly exposed individuals, as well as to examine the dynamics of viral infection within families. Transmission of SARS-CoV-2 between family members represented a major route for viral spread during the early stages of the pandemic, due to the nature of SARS-CoV-2 transmission through close contacts. Methods: Here, humoral and cellular immunity is explored in 264 SARS-CoV-2 infected, exposed or unexposed individuals from 81 families in the United Kingdom sampled in the winter of 2020 before widespread vaccination and infection. Results: We describe robust cellular and humoral immunity into COVID-19 convalescence, albeit with marked heterogeneity between families and between individuals. T-cell response magnitude is associated with male sex and older age by multiple linear regression. SARS-CoV-2-specific T-cell responses in seronegative individuals are widespread, particularly in adults and in individuals exposed to SARS-CoV-2 through an infected family member. The magnitude of this response is associated with the number of seropositive family members, with a greater number of seropositive individuals within a family leading to stronger T-cell immunity in seronegative individuals. Discussion: These results support a model whereby exposure to SARS-CoV-2 promotes T-cell immunity in the absence of an antibody response. The source of these seronegative T-cell responses to SARS-CoV-2 has been suggested as cross-reactive immunity to endemic coronaviruses that is expanded upon SARS-CoV-2 exposure. However, in this study, no association between HCoV-specific immunity and seronegative T-cell immunity to SARS-CoV-2 is identified, suggesting that de novo T-cell immunity may be generated in seronegative SARS-CoV-2 exposed individuals.
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COVID-19 , SARS-CoV-2 , Adulto , Humanos , Masculino , Imunidade Celular , Antivirais , FamíliaRESUMO
Lactate has long been considered a cellular waste product. However, we found that as extracellular lactate accumulates, it also enters the mitochondrial matrix and stimulates mitochondrial electron transport chain (ETC) activity. The resulting increase in mitochondrial ATP synthesis suppresses glycolysis and increases the utilization of pyruvate and/or alternative respiratory substrates. The ability of lactate to increase oxidative phosphorylation does not depend on its metabolism. Both L- and D-lactate are effective at enhancing ETC activity and suppressing glycolysis. Furthermore, the selective induction of mitochondrial oxidative phosphorylation by unmetabolized D-lactate reversibly suppressed aerobic glycolysis in both cancer cell lines and proliferating primary cells in an ATP-dependent manner and enabled cell growth on respiratory-dependent bioenergetic substrates. In primary T cells, D-lactate enhanced cell proliferation and effector function. Together, these findings demonstrate that lactate is a critical regulator of the ability of mitochondrial oxidative phosphorylation to suppress glucose fermentation.
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BACKGROUND: Beyond systematic reviews and meta-analyses, there have been no direct studies of serological response to COVID-19 in patients with inflammatory bowel disease (IBD) across continents. In particular, there has been limited data from Asia, with no data reported from India. The ICARUS-IBD (International study of COVID-19 Antibody Response Under Sustained immunosuppression in IBD) consortium assessed serological response to SARS-CoV-2 in patients with IBD in North America, Europe, and Asia. METHODS: The ICARUS-IBD study is a multicenter observational cohort study spanning sites in 7 countries. We report seroprevalence data from 2303 patients with IBD before COVID-19 vaccination between May 2020 and November 2021. SARS-CoV-2 anti-spike and anti-nucleocapsid antibodies were analyzed. RESULTS: The highest and lowest SARS-CoV-2 anti-spike seropositivity rates were found in Asia (81.2% in Chandigarh and 57.9% in Delhi, India; and 0% in Hong Kong). By multivariable analysis, country (India: odds ratio [OR], 18.01; 95% confidence interval [CI], 12.03-26.95; P < .0001; United Kingdom: OR, 2.43; 95% CI, 1.58-3.72; P < .0001; United States: OR, 2.21; 95% CI, 1.27-3.85; P = .005), male sex (OR, 1.46; 95% CI, 1.07-1.99; P = .016), and diabetes (OR, 2.37; 95% CI, 1.04-5.46; P = .039) conferred higher seropositivity rates. Biological therapies associated with lower seroprevalence (OR, 0.22; 95% CI, 0.15-0.33; P < .0001). Multiple linear regression showed associations between anti-spike and anti-nucleocapsid titers with medications (P < .0001) but not with country (P = .3841). CONCLUSIONS: While the effects of medications on anti-SARS-CoV-2 antibody titers in patients with IBD were consistent across sites, geographical location conferred the highest risk of susceptibility to serologically detectable SARS-CoV-2 infection. Over half of IBD patients in India were seropositive prior to vaccination. These insights can help to inform shielding advice, therapeutic choices, and vaccine strategies in IBD patients for COVID-19 and future viral challenges.
In this multinational study of SARS-CoV-2 seroprevalence prior to vaccination, including the first data from India, where over half of patients seroconverted, geographical location conferred the highest risk of susceptibility to serologically detectable infection.
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COVID-19 , Doenças Inflamatórias Intestinais , Humanos , Masculino , SARS-CoV-2 , Vacinas contra COVID-19 , Estudos Soroepidemiológicos , Geografia , Anticorpos AntiviraisRESUMO
Oncogenic mutations in isocitrate dehydrogenases 1 and 2 (IDH1/2) produce 2-hydroxyglutarate (2HG), which inhibits dioxygenases that modulate chromatin dynamics. The effects of 2HG have been reported to sensitize IDH tumors to poly-(ADP-ribose) polymerase (PARP) inhibitors. However, unlike PARP-inhibitor-sensitive BRCA1/2 tumors, which exhibit impaired homologous recombination, IDH-mutant tumors have a silent mutational profile and lack signatures associated with impaired homologous recombination. Instead, 2HG-producing IDH mutations lead to a heterochromatin-dependent slowing of DNA replication accompanied by increased replication stress and DNA double-strand breaks. This replicative stress manifests as replication fork slowing, but the breaks are repaired without a significant increase in mutation burden. Faithful resolution of replicative stress in IDH-mutant cells is dependent on poly-(ADP-ribosylation). Treatment with PARP inhibitors increases DNA replication but results in incomplete DNA repair. These findings demonstrate a role for PARP in the replication of heterochromatin and further validate PARP as a therapeutic target in IDH-mutant tumors.
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Proteína BRCA1 , Neoplasias , Humanos , Proteína BRCA1/genética , Heterocromatina/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Proteína BRCA2/genética , Recombinação Homóloga/genética , Neoplasias/tratamento farmacológico , Neoplasias/genética , Mutação , Isocitrato Desidrogenase/genéticaRESUMO
Pathogen infection and tissue injury are universal insults that disrupt homeostasis. Innate immunity senses microbial infections and induces cytokines/chemokines to activate resistance mechanisms. Here, we show that, in contrast to most pathogen-induced cytokines, interleukin-24 (IL-24) is predominately induced by barrier epithelial progenitors after tissue injury and is independent of microbiome or adaptive immunity. Moreover, Il24 ablation in mice impedes not only epidermal proliferation and re-epithelialization but also capillary and fibroblast regeneration within the dermal wound bed. Conversely, ectopic IL-24 induction in the homeostatic epidermis triggers global epithelial-mesenchymal tissue repair responses. Mechanistically, Il24 expression depends upon both epithelial IL24-receptor/STAT3 signaling and hypoxia-stabilized HIF1α, which converge following injury to trigger autocrine and paracrine signaling involving IL-24-mediated receptor signaling and metabolic regulation. Thus, parallel to innate immune sensing of pathogens to resolve infections, epithelial stem cells sense injury signals to orchestrate IL-24-mediated tissue repair.
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Citocinas , Ferimentos e Lesões , Animais , Camundongos , Imunidade Adaptativa , Quimiocinas , Epiderme , Imunidade Inata , Ferimentos e Lesões/imunologiaRESUMO
Cancer-associated fibroblasts (CAF) are a major cell type in the stroma of solid tumors and can exert both tumor-promoting and tumor-restraining functions. CAF heterogeneity is frequently observed in pancreatic ductal adenocarcinoma (PDAC), a tumor characterized by a dense and hypoxic stroma that features myofibroblastic CAFs (myCAF) and inflammatory CAFs (iCAF) that are thought to have opposing roles in tumor progression. While CAF heterogeneity can be driven in part by tumor cell-produced cytokines, other determinants shaping CAF identity and function are largely unknown. In vivo, we found that iCAFs displayed a hypoxic gene expression and biochemical profile and were enriched in hypoxic regions of PDAC tumors, while myCAFs were excluded from these regions. Hypoxia led fibroblasts to acquire an inflammatory gene expression signature and synergized with cancer cell-derived cytokines to promote an iCAF phenotype in a HIF1α-dependent fashion. Furthermore, HIF1α stabilization was sufficient to induce an iCAF phenotype in stromal cells introduced into PDAC organoid cocultures and to promote PDAC tumor growth. These findings indicate hypoxia-induced HIF1α as a regulator of CAF heterogeneity and promoter of tumor progression in PDAC. SIGNIFICANCE: Hypoxia in the tumor microenvironment of pancreatic cancer potentiates the cytokine-induced inflammatory CAF phenotype and promotes tumor growth. See related commentary by Fuentes and Taniguchi, p. 1560.
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Fibroblastos Associados a Câncer , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Citocinas/metabolismo , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia , Fibroblastos/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Fenótipo , Microambiente Tumoral , Neoplasias PancreáticasRESUMO
AIM: This study explored caregiver-reported first signs of autism and caregiver experiences of reporting these signs to health professionals using a multiple methods approach. BACKGROUND: Within the Australian context, children who have been diagnosed with autism represent a significant proportion of individuals requiring access to disability services. Due to the importance of accessing early intervention services to support future outcomes, it is vital that first signs are noticed, reported, and the diagnosis process begun as soon as possible. METHOD: Phase 1 of the study included a secondary analysis of a survey of caregivers, while phase 2 consisted of focus groups of caregivers of children on the autism spectrum. RESULTS: Survey data indicated that most children were aged 12-18 months when first signs were noticed, with first signs noticed earlier in females than males. Children were age 2-6 years when caregivers sought advice and received a diagnosis. Uncertainty and a lack of information often left caregivers feeling frustrated and under-supported when seeking advice and diagnosis. Despite first signs being recognised early by caregivers, barriers to information and seeking help and support resulted in significant delays in receiving a diagnosis. CONCLUSIONS: The study provides valuable consideration of the caregiver perspective regarding reported first signs of autism and the additional challenges faced by caregivers living in regional and rural areas. By being more informed of what caregivers first notice, health professionals may also be able to provide better support and advice to caregivers in regard to access to diagnosis and early intervention services.
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Transtorno do Espectro Autista , Transtorno Autístico , Masculino , Criança , Feminino , Humanos , Transtorno Autístico/diagnóstico , Cuidadores , Austrália , Emoções , Inquéritos e QuestionáriosRESUMO
Despite suicide ideation being one of the most frequently reported health issues impacting tertiary students, there is a paucity of research evaluating the efficacy of preventive interventions aimed at improving mental health outcomes for students studying at two tertiary institutes. The current study evaluated the efficacy of the "Talk-to-Me" Mass Open Online Course (MOOC) in improving tertiary students' abilities to support the mental health of themselves and their peers via a randomised controlled trial design, comparing them to a waitlist control group. Overall, 129 tertiary students (M = 25.22 years, SD = 7.43; 80% female) undertaking a health science or education course at two Western Australian universities were randomly allocated to either "Talk-to-Me" (n = 66) or waitlist control (n = 63) groups. The participants' responses to suicidal statements (primary outcome), knowledge of mental health, generalised self-efficacy, coping skills, and overall utility of the program (secondary outcomes) were collected at three timepoints (baseline 10-weeks and 24-weeks from baseline). Assessment time and group interaction were explored using a random-effects regression model, examining changes in the primary and secondary outcomes. Intention-to-treat analysis (N = 129) at 10-weeks demonstrated a significant improvement in generalised self-efficacy for "Talk-to-Me" compared to the control group (ES = 0.36, p = .04), with only the "Talk-to-Me" participants reporting increased knowledge in responding to suicidal ideation (primary outcome). This change was sustained for 24 weeks. Findings provide preliminary evidence suggesting that the "Talk-to-Me" MOOC can effectively improve tertiary students' mental health and knowledge of how to support themselves and others in distress. ACTRN12619000630112, registered 18-03-2019, anzctr.org.au.
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Estudantes , Prevenção do Suicídio , Feminino , Humanos , Masculino , Austrália , Educação em Saúde , Saúde Mental , Estudantes/psicologia , Estudos Cross-OverRESUMO
Mature forests provide important wildlife habitat and support critical ecosystem functions globally. Within the dry conifer forests of the western United States, past management and fire exclusion have contributed to forest conditions that are susceptible to increasingly severe wildfire and drought. We evaluated declines in conifer forest cover in the southern Sierra Nevada of California during a decade of record disturbance by using spatially comprehensive forest structure estimates, wildfire perimeter data, and the eDaRT forest disturbance tracking algorithm. Primarily due to the combination of wildfires, drought, and drought-associated beetle epidemics, 30% of the region's conifer forest extent transitioned to nonforest vegetation during 2011-2020. In total, 50% of mature forest habitat and 85% of high density mature forests either transitioned to lower density forest or nonforest vegetation types. California spotted owl protected activity centers (PAC) experienced greater canopy cover decline (49% of 2011 cover) than non-PAC areas (42% decline). Areas with high initial canopy cover and without tall trees were most vulnerable to canopy cover declines, likely explaining the disproportionate declines of mature forest habitat and within PACs. Drought and beetle attack caused greater cumulative declines than areas where drought and wildfire mortality overlapped, and both types of natural disturbance far outpaced declines attributable to mechanical activities. Drought mortality that disproportionately affects large conifers is particularly problematic to mature forest specialist species reliant on large trees. However, patches of degraded forests within wildfire perimeters were larger with greater core area than those outside burned areas, and remnant forest habitats were more fragmented within burned perimeters than those affected by drought and beetle mortality alone. The percentage of mature forest that survived and potentially benefited from lower severity wildfire increased over time as the total extent of mature forest declined. These areas provide some opportunity for improved resilience to future disturbances, but strategic management interventions are likely also necessary to mitigate worsening mega-disturbances. Remaining dry mature forest habitat in California may be susceptible to complete loss in the coming decades without a rapid transition from a conservation paradigm that attempts to maintain static conditions to one that manages for sustainable disturbance dynamics.