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1.
Am J Hum Genet ; 110(2): 284-299, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36693378

RESUMO

Insulin secretion is critical for glucose homeostasis, and increased levels of the precursor proinsulin relative to insulin indicate pancreatic islet beta-cell stress and insufficient insulin secretory capacity in the setting of insulin resistance. We conducted meta-analyses of genome-wide association results for fasting proinsulin from 16 European-ancestry studies in 45,861 individuals. We found 36 independent signals at 30 loci (p value < 5 × 10-8), which validated 12 previously reported loci for proinsulin and ten additional loci previously identified for another glycemic trait. Half of the alleles associated with higher proinsulin showed higher rather than lower effects on glucose levels, corresponding to different mechanisms. Proinsulin loci included genes that affect prohormone convertases, beta-cell dysfunction, vesicle trafficking, beta-cell transcriptional regulation, and lysosomes/autophagy processes. We colocalized 11 proinsulin signals with islet expression quantitative trait locus (eQTL) data, suggesting candidate genes, including ARSG, WIPI1, SLC7A14, and SIX3. The NKX6-3/ANK1 proinsulin signal colocalized with a T2D signal and an adipose ANK1 eQTL signal but not the islet NKX6-3 eQTL. Signals were enriched for islet enhancers, and we showed a plausible islet regulatory mechanism for the lead signal in the MADD locus. These results show how detailed genetic studies of an intermediate phenotype can elucidate mechanisms that may predispose one to disease.


Assuntos
Diabetes Mellitus Tipo 2 , Proinsulina , Humanos , Proinsulina/genética , Proinsulina/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Estudo de Associação Genômica Ampla/métodos , Insulina/genética , Insulina/metabolismo , Glucose , Fatores de Transcrição/genética , Proteínas de Homeodomínio/genética
2.
J Virol ; 98(2): e0157123, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38206036

RESUMO

In pandemic scenarios involving novel human pathogenic viruses, it is highly desirable that vaccines induce strong neutralizing antibodies as quickly as possible. However, current vaccine strategies require multiple immunization doses to produce high titers of neutralizing antibodies and are poorly protective after a single vaccination. We therefore wished to design a vaccine candidate that would induce increased protective immune responses following the first vaccine dose. We hypothesized that antibodies against the receptor-binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike glycoprotein could be increased by drawing upon immunity to a previous infection. We generated a fusion protein containing the influenza H1N1 PR8 virus nucleoprotein (NP) and the SARS-CoV-2 spike RBD. Mice with or without preexisting immunity to PR8 were then vaccinated with NP/RBD. We observed significantly increased SARS-CoV-2 neutralizing antibodies in mice with PR8 immunity compared to mice without preexisting PR8 immunity. Vaccination with NP/RBD protected mice from SARS-CoV-2-induced morbidity and mortality after a single dose. Additionally, we compared SARS-CoV-2 virus titers in the lungs and nasal turbinates 4 days post-challenge of mice vaccinated with NP/RBD. SARS-CoV-2 virus was detectable in the lungs and nasal turbinate of mice without preexisting PR8 immunity, while SARS-CoV-2 virus was completely undetectable in mice with preexisting PR8 immunity. We also found that CD4-positive T cells in mice with preexisting immunity to PR8 play an essential role in producing the increased antibody response against RBD. This vaccine strategy potentially can be modified to target other pathogens of concern and offers extra value in future pandemic scenarios.IMPORTANCEIncreased globalization and changes in human interactions with wild animals has increased the likelihood of the emergence of novel viruses with pandemic potential. Vaccines can be effective in preventing severe disease caused by pandemic viruses. However, it takes time to develop protective immunity via prime-boost vaccination. More effective vaccine designs should quickly induce protective immunity. We propose leveraging preexisting immunity to a different pathogen to boost protection against emerging viruses. We targeted SARS-CoV-2 as a representative pandemic virus and generated a fusion protein vaccine that combines the nucleoprotein from influenza A virus and the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein. Our vaccine design significantly increased the production of RBD-specific antibodies in mice that had previously been exposed to influenza virus, compared to those without previous exposure. This enhanced immunity reduced SARS-CoV-2 replication in mice. Our results offer a vaccine design that could be valuable in a future pandemic setting.


Assuntos
Vacinas contra COVID-19 , Vacinas contra Influenza , Animais , Humanos , Camundongos , Anticorpos Neutralizantes , Anticorpos Antivirais , Formação de Anticorpos , COVID-19/imunologia , COVID-19/prevenção & controle , Vírus da Influenza A Subtipo H1N1/fisiologia , Vacinas contra Influenza/imunologia , Nucleoproteínas , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/química , Vacinas contra COVID-19/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle
3.
PLoS Genet ; 18(11): e1010477, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36350884

RESUMO

Myelin is essential for rapid nerve impulse propagation and axon protection. Accordingly, defects in myelination or myelin maintenance lead to secondary axonal damage and subsequent degeneration. Studies utilizing genetic (CNPase-, MAG-, and PLP-null mice) and naturally occurring neuropathy models suggest that myelinating glia also support axons independently from myelin. Myelin protein zero (MPZ or P0), which is expressed only by Schwann cells, is critical for myelin formation and maintenance in the peripheral nervous system. Many mutations in MPZ are associated with demyelinating neuropathies (Charcot-Marie-Tooth disease type 1B [CMT1B]). Surprisingly, the substitution of threonine by methionine at position 124 of P0 (P0T124M) causes axonal neuropathy (CMT2J) with little to no myelin damage. This disease provides an excellent paradigm to understand how myelinating glia support axons independently from myelin. To study this, we generated targeted knock-in MpzT124M mutant mice, a genetically authentic model of T124M-CMT2J neuropathy. Similar to patients, these mice develop axonopathy between 2 and 12 months of age, characterized by impaired motor performance, normal nerve conduction velocities but reduced compound motor action potential amplitudes, and axonal damage with only minor compact myelin modifications. Mechanistically, we detected metabolic changes that could lead to axonal degeneration, and prominent alterations in non-compact myelin domains such as paranodes, Schmidt-Lanterman incisures, and gap junctions, implicated in Schwann cell-axon communication and axonal metabolic support. Finally, we document perturbed mitochondrial size and distribution along MpzT124M axons suggesting altered axonal transport. Our data suggest that Schwann cells in P0T124M mutant mice cannot provide axons with sufficient trophic support, leading to reduced ATP biosynthesis and axonopathy. In conclusion, the MpzT124M mouse model faithfully reproduces the human neuropathy and represents a unique tool for identifying the molecular basis for glial support of axons.


Assuntos
Doença de Charcot-Marie-Tooth , Humanos , Camundongos , Animais , Doença de Charcot-Marie-Tooth/genética , Bainha de Mielina/genética , Bainha de Mielina/metabolismo , Axônios/metabolismo , Neuroglia , Camundongos Knockout , Modelos Animais de Doenças , Comunicação
4.
J Neuroinflammation ; 21(1): 189, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095837

RESUMO

BACKGROUND: Infection with the protozoan parasite Toxoplasma gondii leads to the formation of lifelong cysts in neurons that can have devastating consequences in the immunocompromised. In the immunocompetent individual, anti-parasitic effector mechanisms and a balanced immune response characterized by pro- and anti-inflammatory cytokine production establishes an asymptomatic infection that rarely leads to neurological symptoms. Several mechanisms are known to play a role in this successful immune response in the brain including T cell production of IFNγ and IL-10 and the involvement of CNS resident cells. This limitation of clinical neuropathology during chronic infection suggests a balance between immune response and neuroprotective mechanisms that collectively prevent clinical manifestations of disease. However, how these two vital mechanisms of protection interact during chronic Toxoplasma infection remains poorly understood. MAIN TEXT: This study demonstrates a previously undescribed connection between innate neutrophils found chronically in the brain, termed "chronic brain neutrophils" (CBNeuts), and neuroprotective mechanisms during Toxoplasma infection. Lack of CBNeuts during chronic infection, accomplished via systemic neutrophil depletion, led to enhanced infection and deleterious effects on neuronal regeneration and repair mechanisms in the brain. Phenotypic and transcriptomic analysis of CBNeuts identified them as distinct from peripheral neutrophils and revealed two main subsets of CBNeuts that display heterogeneity towards both classical effector and neuroprotective functions in an age-dependent manner. Further phenotypic profiling defined expression of the neuroprotective molecules NRG-1 andErbB4 by these cells, and the importance of this signaling pathway during chronic infection was demonstrated via NRG-1 treatment studies. CONCLUSIONS: In conclusion, this work identifies CBNeuts as a heterogenous population geared towards both classical immune responses and neuroprotection during chronic Toxoplasma infection and provides the foundation for future mechanistic studies of these cells.


Assuntos
Neutrófilos , Toxoplasmose , Animais , Neutrófilos/imunologia , Neutrófilos/metabolismo , Camundongos , Toxoplasmose/imunologia , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Neurônios/imunologia , Toxoplasma/imunologia , Feminino , Neuroproteção/fisiologia , Masculino , Encéfalo/imunologia , Encéfalo/patologia , Encéfalo/parasitologia
5.
PLoS Genet ; 17(4): e1009455, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33872308

RESUMO

Expression quantitative trait loci (eQTL) studies are used to understand the regulatory function of non-coding genome-wide association study (GWAS) risk loci, but colocalization alone does not demonstrate a causal relationship of gene expression affecting a trait. Evidence for mediation, that perturbation of gene expression in a given tissue or developmental context will induce a change in the downstream GWAS trait, can be provided by two-sample Mendelian Randomization (MR). Here, we introduce a new statistical method, MRLocus, for Bayesian estimation of the gene-to-trait effect from eQTL and GWAS summary data for loci with evidence of allelic heterogeneity, that is, containing multiple causal variants. MRLocus makes use of a colocalization step applied to each nearly-LD-independent eQTL, followed by an MR analysis step across eQTLs. Additionally, our method involves estimation of the extent of allelic heterogeneity through a dispersion parameter, indicating variable mediation effects from each individual eQTL on the downstream trait. Our method is evaluated against other state-of-the-art methods for estimation of the gene-to-trait mediation effect, using an existing simulation framework. In simulation, MRLocus often has the highest accuracy among competing methods, and in each case provides more accurate estimation of uncertainty as assessed through interval coverage. MRLocus is then applied to five candidate causal genes for mediation of particular GWAS traits, where gene-to-trait effects are concordant with those previously reported. We find that MRLocus's estimation of the causal effect across eQTLs within a locus provides useful information for determining how perturbation of gene expression or individual regulatory elements will affect downstream traits. The MRLocus method is implemented as an R package available at https://mikelove.github.io/mrlocus.


Assuntos
Perfilação da Expressão Gênica/estatística & dados numéricos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/estatística & dados numéricos , Locos de Características Quantitativas/genética , Simulação por Computador , Regulação da Expressão Gênica/genética , Humanos , Desequilíbrio de Ligação , Análise da Randomização Mendeliana , Modelos Genéticos , Transcriptoma/genética
6.
Child Care Health Dev ; 50(4): e13303, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38991712

RESUMO

BACKGROUND: Children and young people (CYP) with complex neurodisability experience multiple physical, communication, educational and social challenges, which require complex packages of multidisciplinary care. Part of the holistic care required includes supporting the families and parents/caregivers. The aim of the wider study was to introduce a new programme ('Ubuntu') to parents/caregivers and healthcare professionals (HCPs) in order to test the feasibility and acceptability of the concept and content, with the goal of potential adaptation for the UK in mind. Data collection and analysis uncovered rich data on caregiving journeys, navigation of health services, and perceived service gaps. This paper focuses solely on these topics. Further papers will report on the feasibility and adaptation data. METHODS: Two rounds of semi-structured interviews were conducted with 12 caregivers of CYP with complex neurodisability and six HCPs from a variety of disciplines, recruited from a community child health service in London Borough of Newham, UK in 2020. The interviews included open-ended questions to explore caregiving journeys, experiences of navigating health services and perceived service gaps. Transcripts were analysed using a data-driven inductive thematic analysis. RESULTS: Three themes were identified that related to the aim of understanding caregivers' experiences and unmet needs relating to current service provision. These were (1) Caregiver Mental Health, (2) The Information Gap and (3) The Need for Holistic Support. Mental health difficulties were reported, particularly around the period of diagnosis. Priority needs included the provision of clear information about the diagnosis and services offered, opportunities to forge peer support networks and for services across the community to collaborate. CONCLUSIONS: The delivery of health services for CYP with neurodisability should encompass the broad needs of the family as well as meeting the clinical needs of the CYP.


Assuntos
Cuidadores , Necessidades e Demandas de Serviços de Saúde , Pesquisa Qualitativa , Humanos , Cuidadores/psicologia , Criança , Masculino , Feminino , Adolescente , Reino Unido , Acessibilidade aos Serviços de Saúde , Pré-Escolar , Avaliação das Necessidades , Adulto , Serviços de Saúde da Criança/organização & administração , Crianças com Deficiência/reabilitação , Pais/psicologia , Pessoal de Saúde/psicologia , Adulto Jovem
7.
Int J Mol Sci ; 25(14)2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39063229

RESUMO

Diabetic bone disease (DBD) is a frequent complication in patients with type 2 diabetes mellitus (T2DM), characterised by altered bone mineral density (BMD) and bone turnover marker (BTMs) levels. The impact of different anti-diabetic medications on the skeleton remains unclear, and studies have reported conflicting results; thus, the need for a comprehensive systematic review is of paramount importance. A systematic search was conducted in PubMed and the Cochrane Library. The primary outcomes assessed were changes in BMD in relation to different anatomical sites and BTMs, including mainly P1NP and CTX as well as OPG, OCN, B-ALP and RANK-L. Risk of bias was evaluated using the JADAD score. The meta-analysis of 19 randomised controlled trials comprising 4914 patients showed that anti-diabetic medications overall increased BMD at the lumbar spine (SMD: 0.93, 95% CI [0.13, 1.73], p = 0.02), femoral neck (SMD: 1.10, 95% CI [0.47, 1.74], p = 0.0007) and in total hip (SMD: 0.33, 95% CI [-0.25, 0.92], p = 0.27) in comparison with placebo, but when compared with metformin, the overall effect favoured metformin over other treatments (SMD: -0.23, 95% CI [-0.39, -0.07], p = 0.004). GLP-1 receptor agonists and insulin analogues seem to improve BMD compared to placebo, while SGLT2 inhibitors and thiazolidinediones (TZDs) showed no significant effect, although studies' number cannot lead to safe conclusions. For BTMs, TZDs significantly increased P1NP levels compared to placebo. However, no significant differences were observed for CTX, B-ALP, OCN, OPG, and RANK-L between anti-diabetic drugs and metformin or placebo. High heterogeneity and diverse follow-up durations among studies were evident, which obscures the validity of the results. This review highlights the variable effects of anti-diabetic drugs on DBD in T2DM patients, emphasising the need for long-term trials with robust designs to better understand these relationships and inform clinical decisions.


Assuntos
Biomarcadores , Densidade Óssea , Remodelação Óssea , Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Densidade Óssea/efeitos dos fármacos , Hipoglicemiantes/uso terapêutico , Remodelação Óssea/efeitos dos fármacos , Metformina/uso terapêutico
8.
Clin Sci (Lond) ; 137(10): 773-784, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37219941

RESUMO

Systematic reviews and meta-analysis are the cornerstones of evidence-based decision making and priority setting. However, traditional systematic reviews are time and labour intensive, limiting their feasibility to comprehensively evaluate the latest evidence in research-intensive areas. Recent developments in automation, machine learning and systematic review technologies have enabled efficiency gains. Building upon these advances, we developed Systematic Online Living Evidence Summaries (SOLES) to accelerate evidence synthesis. In this approach, we integrate automated processes to continuously gather, synthesise and summarise all existing evidence from a research domain, and report the resulting current curated content as interrogatable databases via interactive web applications. SOLES can benefit various stakeholders by (i) providing a systematic overview of current evidence to identify knowledge gaps, (ii) providing an accelerated starting point for a more detailed systematic review, and (iii) facilitating collaboration and coordination in evidence synthesis.


Assuntos
Automação , Medicina Baseada em Evidências , Software , Tecnologia , Mineração de Dados , Aprendizado de Máquina
9.
Clin Sci (Lond) ; 137(2): 181-193, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36630537

RESUMO

OBJECTIVE: Existing strategies to identify relevant studies for systematic review may not perform equally well across research domains. We compare four approaches based on either human or automated screening of either title and abstract or full text, and report the training of a machine learning algorithm to identify in vitro studies from bibliographic records. METHODS: We used a systematic review of oxygen-glucose deprivation (OGD) in PC-12 cells to compare approaches. For human screening, two reviewers independently screened studies based on title and abstract or full text, with disagreements reconciled by a third. For automated screening, we applied text mining to either title and abstract or full text. We trained a machine learning algorithm with decisions from 2000 randomly selected PubMed Central records enriched with a dataset of known in vitro studies. RESULTS: Full-text approaches performed best, with human (sensitivity: 0.990, specificity: 1.000 and precision: 0.994) outperforming text mining (sensitivity: 0.972, specificity: 0.980 and precision: 0.764). For title and abstract, text mining (sensitivity: 0.890, specificity: 0.995 and precision: 0.922) outperformed human screening (sensitivity: 0.862, specificity: 0.998 and precision: 0.975). At our target sensitivity of 95% the algorithm performed with specificity of 0.850 and precision of 0.700. CONCLUSION: In this in vitro systematic review, human screening based on title and abstract erroneously excluded 14% of relevant studies, perhaps because title and abstract provide an incomplete description of methods used. Our algorithm might be used as a first selection phase in in vitro systematic reviews to limit the extent of full text screening required.


Assuntos
Algoritmos , Mineração de Dados , Humanos , Mineração de Dados/métodos , Projetos de Pesquisa , Aprendizado de Máquina , Glucose
10.
Brain Behav Immun ; 114: 131-143, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37604212

RESUMO

Within the brain, a pro-inflammatory response is essential to prevent clinical disease due to Toxoplasma gondii reactivation. Infection in the immunocompromised leads to lethal Toxoplasmic encephalitis while in the immunocompetent, there is persistent low-grade inflammation which is devoid of clinical symptoms. This signifies that there is a well-balanced and regulated inflammatory response to T. gondii in the brain. T cells are the dominant immune cells that prevent clinical disease, and this is mediated through the secretion of effector molecules such as perforins and IFN-γ. The presence of cognate antigen, the expression of survival cytokines, and the alteration of the epigenetic landscape drive the development of memory T cells. However, specific extrinsic signals that promote the formation and maintenance of memory T cells within tissue are poorly understood. During chronic infection, there is an increase in extracellular glutamate that, due to its function as an excitatory neurotransmitter, is normally tightly controlled in the CNS. Here we demonstrate that CD8+ T cells from the T. gondii-infected brain parenchyma are enriched for metabotropic glutamate receptors (mGluR's). Characterization studies determined that mGluR+ expression by CD8+ T cells defines a distinct memory population at the transcriptional and protein level. Finally, using receptor antagonists and agonists we demonstrate mGluR signaling is required for optimal CD8+ T cell production of the effector cytokine IFNγ. This work suggests that glutamate is an important environmental signal of inflammation that promotes T cell function. Understanding glutamate's influence on T cells in the brain can provide insights into the mechanisms that govern protective immunity against CNS-infiltrating pathogens and neuroinflammation.

11.
Neural Comput ; 35(12): 1938-1969, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37844325

RESUMO

Prior applications of the cerebellar adaptive filter model have included a range of tasks within simulated and robotic systems. However, this has been limited to systems driven by continuous signals. Here, the adaptive filter model of the cerebellum is applied to the control of a system driven by spiking inputs by considering the problem of controlling muscle force. The performance of the standard adaptive filter algorithm is compared with the algorithm with a modified learning rule that minimizes inputs and a simple proportional-integral-derivative (PID) controller. Control performance is evaluated in terms of the number of spikes, the accuracy of spike input locations, and the accuracy of muscle force output. Results show that the cerebellar adaptive filter model can be applied without change to the control of systems driven by spiking inputs. The cerebellar algorithm results in good agreement between input spikes and force outputs and significantly improves on a PID controller. Input minimization can be used to reduce the number of spike inputs, but at the expense of a decrease in accuracy of spike input location and force output. This work extends the applications of the cerebellar algorithm and demonstrates the potential of the adaptive filter model to be used to improve functional electrical stimulation muscle control.


Assuntos
Algoritmos , Cerebelo , Cerebelo/fisiologia , Aprendizagem/fisiologia , Músculos
12.
Parasite Immunol ; 45(12): e13011, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37776091

RESUMO

The protozoan parasite Toxoplasma gondii infects approximately 2.5 billion people worldwide. Infection induces a rapid dissemination of parasites throughout the body followed by the formation of lifelong cysts within neurons of the host brain. Both stages require a dynamic immune response comprised of both innate and adaptive cells. Neutrophils are a primary responding cell to acute infection and have been observed in the brain during murine chronic infection. Previous studies investigating human neutrophils found that invasion by Toxoplasma tachyzoites inhibits apoptosis of neutrophils, prolonging their survival under inflammatory conditions. Here, we demonstrate the differentiation of two distinct subsets following exposure of human neutrophil-like-cells (HNLC) to Toxoplasma cysts. In vitro stimulation and imaging studies show cyst-specific induction of cytokines and cyst clearance by HNLCs. Further testing demonstrates that aged HNLCs perform less phagocytosis of cysts compared to non-aged HNLCs. In conclusion, this study identifies a novel response of HNLCs to Toxoplasma cysts and may indicate a role for neutrophils in the clearance of cysts during human infection with Toxoplasma.


Assuntos
Anti-Infecciosos , Toxoplasma , Humanos , Animais , Camundongos , Idoso , Neutrófilos , Encéfalo/parasitologia , Citocinas
13.
PLoS Genet ; 16(10): e1008844, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33085661

RESUMO

Balanced mitochondrial fission and fusion play an important role in shaping and distributing mitochondria, as well as contributing to mitochondrial homeostasis and adaptation to stress. In particular, mitochondrial fission is required to facilitate degradation of damaged or dysfunctional units via mitophagy. Two Parkinson's disease factors, PINK1 and Parkin, are considered key mediators of damage-induced mitophagy, and promoting mitochondrial fission is sufficient to suppress the pathological phenotypes in Drosophila Pink1/parkin mutants. We sought additional factors that impinge on mitochondrial dynamics and which may also suppress Pink1/parkin phenotypes. We found that the Drosophila phosphatidylinositol 4-kinase IIIß homologue, Four wheel drive (Fwd), promotes mitochondrial fission downstream of the pro-fission factor Drp1. Previously described only as male sterile, we identified several new phenotypes in fwd mutants, including locomotor deficits and shortened lifespan, which are accompanied by mitochondrial dysfunction. Finally, we found that fwd overexpression can suppress locomotor deficits and mitochondrial disruption in Pink1/parkin mutants, consistent with its function in promoting mitochondrial fission. Together these results shed light on the complex mechanisms of mitochondrial fission and further underscore the potential of modulating mitochondrial fission/fusion dynamics in the context of neurodegeneration.


Assuntos
Proteínas do Citoesqueleto/genética , Proteínas de Drosophila/genética , Proteínas de Ligação ao GTP/genética , Doença de Parkinson/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Proteínas Serina-Treonina Quinases/genética , Ubiquitina-Proteína Ligases/genética , Animais , Modelos Animais de Doenças , Drosophila melanogaster/genética , Regulação da Expressão Gênica/genética , Humanos , Locomoção/genética , Mitocôndrias/genética , Mitocôndrias/patologia , Dinâmica Mitocondrial/genética , Mitofagia/genética , Proteínas Mutantes/genética , Degeneração Neural/genética , Degeneração Neural/patologia , Doença de Parkinson/patologia
14.
J Adolesc ; 95(1): 5-33, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36210652

RESUMO

INTRODUCTION: Bullying victimization has consistently been highlighted as a risk factor for self-injurious thoughts and behaviors (SITBs) in young people. This systematic review of prospective, community-based studies explored associations between bullying victimization (traditional/face-to-face and cyber) across the full spectrum of self-harm and suicidality, in children and young people aged up to (and including) 25 years. Importantly, associations by sex/gender were explored. METHODS: MEDLINE, Embase, PsycINFO, CINAHL and Scopus were searched for articles meeting the inclusion criteria. Articles were screened by title, abstract and full text. Quality appraisal was performed using the Newcastle-Ottawa Scale for cohort studies. Data were synthesized narratively. The protocol is registered on PROSPERO (CRD42021261916) and followed PRISMA 2020 guidelines. RESULTS: A total of 35 papers were included, across 17 countries. Results were presented by bullying type: traditional/face-to-face (n = 25), cyber (n = 7) and/or an aggregate of both types (n = 7). Outcomes included suicidal ideation (n = 17), self-harm (n = 10), suicide attempt (n = 4), NSSI (n = 4), other (n = 7). Studies measured outcomes in under 18s (n = 24), 18-25-year-olds (n = 8) and both under 18s and 18-25-year-olds (n = 3). Studies exploring the role of sex/gender (20%) found some interesting nuances. CONCLUSIONS: Some weak to strong associations between bullying and SITBs were found yet conclusions are tentative due to study heterogeneity (e.g., methods used, conceptualizations and operationalisations of exposures/outcomes). Future research should address methodological issues raised in this review, and further explore gender differences in bullying, including by bullying sub-types (e.g., overt or relational) and victim status (e.g., victim or bully-victim).


Assuntos
Bullying , Vítimas de Crime , Comportamento Autodestrutivo , Humanos , Criança , Adolescente , Idoso , Estudos Prospectivos , Comportamento Autodestrutivo/epidemiologia , Comportamento Autodestrutivo/etiologia , Tentativa de Suicídio , Ideação Suicida
15.
J Med Libr Assoc ; 111(1-2): 566-578, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37312802

RESUMO

Objectives: Information professionals have supported medical providers, administrators and decision-makers, and guideline creators in the COVID-19 response. Searching COVID-19 literature presented new challenges, including the volume and heterogeneity of literature and the proliferation of new information sources, and exposed existing issues in metadata and publishing. An expert panel developed best practices, including recommendations, elaborations, and examples, for searching during public health emergencies. Methods: Project directors and advisors developed core elements from experience and literature. Experts, identified by affiliation with evidence synthesis groups, COVID-19 search experience, and nomination, responded to an online survey to reach consensus on core elements. Expert participants provided written responses to guiding questions. A synthesis of responses provided the foundation for focus group discussions. A writing group then drafted the best practices into a statement. Experts reviewed the statement prior to dissemination. Results: Twelve information professionals contributed to best practice recommendations on six elements: core resources, search strategies, publication types, transparency and reproducibility, collaboration, and conducting research. Underlying principles across recommendations include timeliness, openness, balance, preparedness, and responsiveness. Conclusions: The authors and experts anticipate the recommendations for searching for evidence during public health emergencies will help information specialists, librarians, evidence synthesis groups, researchers, and decision-makers respond to future public health emergencies, including but not limited to disease outbreaks. The recommendations complement existing guidance by addressing concerns specific to emergency response. The statement is intended as a living document. Future revisions should solicit input from a broader community and reflect conclusions of meta-research on COVID-19 and health emergencies.


Assuntos
COVID-19 , Saúde Pública , Humanos , Emergências , Reprodutibilidade dos Testes , Surtos de Doenças
16.
Br J Nurs ; 32(10): S24-S29, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37219975

RESUMO

BACKGROUND: Teleconsultations were introduced for cancer surgery follow-up to ease pressure on hospital services and facilitate patients' access to those services. There is limited evidence on patients' perceptions of this swift shift in service provision. AIMS: The purpose of this qualitative systematic review was to explore patient experiences of teleconsultations within NHS cancer surgery follow-up services to better understand patient perceptions, satisfaction and acceptability of teleconsultations within cancer services. METHODS: Medline, Embase, PubMed and Google Scholar were searched up to 1 July 2022. Qualitative studies were synthesised using the Braun and Clarke framework. FINDINGS: There were three overarching themes: accessibility; patient experience; and consultation. CONCLUSION: Teleconsultations were widely accepted among cancer surgical patients. However, there were reports of a lack of rapport building and emotional support because of the absence of visual cues and patient camaraderie.


Assuntos
Consulta Remota , Humanos , Pacientes , Reino Unido
17.
J Anat ; 241(5): 1219-1234, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34131911

RESUMO

Recent years have seen an evolving appreciation for the role of glial cells in the nervous system. As we move away from the typical neurocentric view of neuroscience, the complexity and variability of central nervous system glia is emerging, far beyond the three main subtypes: astrocytes, oligodendrocytes, and microglia. Yet the diversity of the glia found in the peripheral nervous system remains rarely discussed. In this review, we discuss the developmental origin, morphology, and function of the different populations of glia found in the peripheral nervous system, including: myelinating Schwann cells, Remak Schwann cells, repair Schwann cells, satellite glia, boundary cap-derived glia, perineurial glia, terminal Schwann cells, glia found in the skin, olfactory ensheathing cells, and enteric glia. The morphological and functional heterogeneity of glia found in the periphery reflects the diverse roles the nervous system performs throughout the body. Further, it highlights a complexity that should be appreciated and considered when it comes to a complete understanding of the peripheral nervous system in health and disease.


Assuntos
Neuroglia , Células de Schwann , Astrócitos , Sistema Nervoso Central , Nervos Periféricos
18.
J Public Health (Oxf) ; 44(4): e506-e513, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-35731995

RESUMO

OBJECTIVES: Exposure to high in fat, sugar or salt (HFSS) food imagery is associated with unhealthy consumption, and subsequently obesity, among young people. We report and compare the results of two content analyses, one of popular children's television channels in the UK and the other of a selection of children's programmes available on video-on-demand (VOD) services. METHODS: Content analysis of 3 days' worth of programmes on two popular children's television channels broadcast on UK television (CBeebies and Milkshake as well as a sample of children's programmes available on the VOD platforms (Netflix and Amazon Prime) using 1-min interval coding. RESULTS: In children's television channels, HFSS content was seen in 181 episodes (36%) and in 417 intervals (13%) on terrestrial television, 'Milkshake' had a significantly higher proportion of broadcasts, which contained HFSS content than 'CBeebies'. In VOD platforms, HFSS content was seen in 82 episodes (72% of the total number of episodes), across 459 intervals (19% of the total number of intervals), with no significant difference in the proportion of programmes containing HFSS content between Netflix and Amazon Prime. CONCLUSIONS: HFSS content is common in both popular UK children's television channels and children programmes on VOD services and is likely having an effect on HFSS consumption in children. Legislative opportunities to prevent this exposure are being missed.


Assuntos
Publicidade , Televisão , Criança , Humanos , Adolescente , Obesidade/prevenção & controle , Reino Unido , Alimentos
19.
J Obstet Gynaecol Can ; 44(3): 303-308, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34563712

RESUMO

Studies show poor maternal and fetal outcomes associated with prenatal cannabis use. With the legalization of cannabis in Canada, it is of timely importance to increase awareness of the effects of its use in pregnancy. An anonymous, online questionnaire was used to assess the pregnant population's knowledge, beliefs, and risk perceptions concerning cannabis. Additionally, educational materials on the effects of prenatal cannabis use were evaluated. A potential knowledge gap was found among 9%-19% of participants, who reported that cannabis posed no risk of harm to the pregnant person or fetus. Moreover, minor changes could improve the effectiveness of educational resources.


Assuntos
Cannabis , Canadá , Feminino , Humanos , Avaliação das Necessidades , Ontário , Gravidez , Cuidado Pré-Natal , Inquéritos e Questionários
20.
Proc Natl Acad Sci U S A ; 116(8): 3183-3192, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30723152

RESUMO

The positioning of chromosomes in the nucleus of a eukaryotic cell is highly organized and has a complex and dynamic relationship with gene expression. In the human malaria parasite Plasmodium falciparum, the clustering of a family of virulence genes correlates with their coordinated silencing and has a strong influence on the overall organization of the genome. To identify conserved and species-specific principles of genome organization, we performed Hi-C experiments and generated 3D genome models for five Plasmodium species and two related apicomplexan parasites. Plasmodium species mainly showed clustering of centromeres, telomeres, and virulence genes. In P. falciparum, the heterochromatic virulence gene cluster had a strong repressive effect on the surrounding nuclear space, while this was less pronounced in Plasmodium vivax and Plasmodium berghei, and absent in Plasmodium yoelii In Plasmodium knowlesi, telomeres and virulence genes were more dispersed throughout the nucleus, but its 3D genome showed a strong correlation with gene expression. The Babesia microti genome showed a classical Rabl organization with colocalization of subtelomeric virulence genes, while the Toxoplasma gondii genome was dominated by clustering of the centromeres and lacked virulence gene clustering. Collectively, our results demonstrate that spatial genome organization in most Plasmodium species is constrained by the colocalization of virulence genes. P. falciparum and P. knowlesi, the only two Plasmodium species with gene families involved in antigenic variation, are unique in the effect of these genes on chromosome folding, indicating a potential link between genome organization and gene expression in more virulent pathogens.


Assuntos
Genoma de Protozoário/genética , Heterocromatina/genética , Malária Falciparum/genética , Plasmodium falciparum/genética , Animais , Centrômero/genética , Regulação da Expressão Gênica/genética , Genômica , Humanos , Malária Falciparum/parasitologia , Plasmodium berghei/genética , Plasmodium berghei/patogenicidade , Plasmodium falciparum/patogenicidade , Plasmodium knowlesi/genética , Plasmodium knowlesi/patogenicidade , Plasmodium vivax/genética , Plasmodium vivax/patogenicidade , Telômero/genética , Toxoplasma/genética , Toxoplasma/patogenicidade
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