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1.
Sensors (Basel) ; 24(12)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38931687

RESUMO

Midlife risk factors such as type 2 diabetes mellitus (T2DM) confer a significantly increased risk of cognitive impairment in later life with executive function, memory, and attention domains often affected first. Spatiotemporal gait characteristics are emerging as important integrative biomarkers of neurocognitive function and of later dementia risk. We examined 24 spatiotemporal gait parameters across five domains of gait previously linked to cognitive function on usual-pace, maximal-pace, and cognitive dual-task gait conditions in 102 middle-aged adults with (57.5 ± 8.0 years; 40% female) and without (57.0 ± 8.3 years; 62.1% female) T2DM. Neurocognitive function was measured using a neuropsychological assessment battery. T2DM was associated with significant changes in gait phases and rhythm domains at usual pace, and greater gait variability observed during maximal pace and dual tasks. In the overall cohort, both the gait pace and rhythm domains were associated with memory and executive function during usual pace. At maximal pace, gait pace parameters were associated with reaction time and delayed memory. During the cognitive dual task, associations between gait variability and both delayed memory/executive function were observed. Associations persisted following covariate adjustment and did not differ by T2DM status. Principal components analysis identified a consistent association of slower gait pace (step/stride length) and increased gait variability during maximal-pace walking with poorer memory and executive function performance. These data support the use of spatiotemporal gait as an integrative biomarker of neurocognitive function in otherwise healthy middle-aged individuals and reveal discrete associations between both differing gait tasks and gait domains with domain-specific neuropsychological performance. Employing both maximal-pace and dual-task paradigms may be important in cognitively unimpaired populations with risk factors for later cognitive decline-with the aim of identifying individuals who may benefit from potential preventative interventions.


Assuntos
Diabetes Mellitus Tipo 2 , Marcha , Testes Neuropsicológicos , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Marcha/fisiologia , Diabetes Mellitus Tipo 2/psicologia , Diabetes Mellitus Tipo 2/fisiopatologia , Função Executiva/fisiologia , Cognição/fisiologia , Memória/fisiologia , Idoso
2.
Int J Mol Sci ; 25(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38791279

RESUMO

Immunosuppressive treatment in patients with rheumatic diseases can maintain disease remission but also increase risk of infection. Their response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination is frequently blunted. In this study we evaluated the effect of immunosuppression exposure on humoral and T cell immune responses to SARS-CoV-2 infection and vaccination in two distinct cohorts of patients; one during acute SARS-CoV-2 infection and 3 months later during convalescence, and another prior to SARS-CoV-2 vaccination, with follow up sampling 6 weeks after vaccination. Results were compared between rituximab-exposed (in previous 6 months), immunosuppression-exposed (in previous 3 months), and non-immunosuppressed groups. The immune cell phenotype was defined by flow cytometry and ELISA. Antigen specific T cell responses were estimated using a whole blood stimulation interferon-γ release assay. A focused post-vaccine assessment of rituximab-treated patients using high dimensional spectral cytometry was conducted. Acute SARS-CoV-2 infection was characterised by T cell lymphopenia, and a reduction in NK cells and naïve CD4 and CD8 cells, without any significant differences between immunosuppressed and non-immunosuppressed patient groups. Conversely, activated CD4 and CD8 cell counts increased in non-immunosuppressed patients with acute SARS-CoV-2 infection but this response was blunted in the presence of immunosuppression. In rituximab-treated patients, antigen-specific T cell responses were preserved in SARS-CoV-2 vaccination, but patients were unable to mount an appropriate humoral response.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Rituximab , SARS-CoV-2 , Vacinação , Humanos , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , SARS-CoV-2/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Vacinas contra COVID-19/imunologia , Rituximab/uso terapêutico , Rituximab/farmacologia , Idoso , Adulto , Terapia de Imunossupressão , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Anticorpos Antivirais/imunologia , Imunidade Humoral/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Imunidade Celular/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-38436476

RESUMO

BACKGROUND: Although type 2 diabetes mellitus (T2DM) is an established risk factor for cognitive impairment, the underlying mechanisms remain poorly explored. One potential mechanism may be through effects of T2DM on cerebral perfusion. The current study hypothesized that T2DM is associated with altered peripheral and central hemodynamic responses to orthostasis, which may in turn be associated with cognitive impairment in T2DM. METHODS: A novel use of function-on-scalar regression, which allows the entire hemodynamic response curve to be modeled, was employed to assess the association between T2DM and hemodynamic responses to orthostasis. Logistic regression was used to assess the relationship between tissue saturation index (TSI), T2DM, and cognitive impairment. All analyses used cross-sectional data from Wave 3 of The Irish Longitudinal Study on Ageing (TILDA). RESULTS: Of 2 984 older adults (aged 64.3 ±â€…8.0; 55% female), 189 (6.3%) had T2DM. T2DM was associated with many features that are indicative of autonomic dysfunction including a blunted peak heart rate and lower diastolic blood pressure. T2DM was associated with reduced TSI and also with greater odds of impaired performance on the Montreal Cognitive Assessment (odds ratio [OR]: 1.62; confidence interval [CI: 1.07, 2.56]; p = .019). Greater TSI was associated with lower odds of impaired performance (OR: 0.90, CI [0.81-0.99]; p = .047). CONCLUSIONS: T2DM was associated with impaired peripheral and cerebral hemodynamic responses to active stand. Both T2DM and reduced cerebral perfusion were associated with impaired cognitive performance. Altered cerebral perfusion may represent an important mechanism linking T2DM and adverse brain health outcomes in older adults.


Assuntos
Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Humanos , Feminino , Idoso , Masculino , Diabetes Mellitus Tipo 2/complicações , Estudos Longitudinais , Tontura , Estudos Transversais , Disfunção Cognitiva/etiologia , Hemodinâmica
4.
Age Ageing ; 53(2)2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38342754

RESUMO

Alzheimer's Disease (ad) is the most common cause of dementia, and in addition to cognitive decline, it directly contributes to physical frailty, falls, incontinence, institutionalisation and polypharmacy in older adults. Increasing availability of clinically validated biomarkers including cerebrospinal fluid and positron emission tomography to assess both amyloid and tau pathology has led to a reconceptualisation of ad as a clinical-biological diagnosis, rather than one based purely on clinical phenotype. However, co-pathology is frequent in older adults which influence the accuracy of biomarker interpretation. Importantly, some older adults with positive amyloid or tau pathological biomarkers may never experience cognitive impairment or dementia. These strides towards achieving an accurate clinical-biological diagnosis are occurring alongside recent positive phase 3 trial results reporting statistically significant effects of anti-amyloid Disease-Modifying Therapies (DMTs) on disease severity in early ad. However, the real-world clinical benefit of these DMTs is not clear and concerns remain regarding how trial results will translate to real-world clinical populations, potential adverse effects (including amyloid-related imaging abnormalities), which can be severe and healthcare systems readiness to afford and deliver potential DMTs to appropriate populations. Here, we review recent advances in both clinical-biological diagnostic classification and future treatment in older adults living with ad. Advocating for access to both more accurate clinical-biological diagnosis and potential DMTs must be done so in a holistic and gerontologically attuned fashion, with geriatricians advocating for enhanced multi-component and multi-disciplinary care for all older adults with ad. This includes those across the ad severity spectrum including older adults potentially ineligible for emerging DMTs.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Idoso , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/tratamento farmacológico , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/terapia , Disfunção Cognitiva/psicologia , Tomografia por Emissão de Pósitrons , Biomarcadores , Fenótipo , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Peptídeos beta-Amiloides/genética
5.
Eur Geriatr Med ; 15(2): 527-537, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38168729

RESUMO

PURPOSE: Antipsychotic use in Alzheimer disease (AD) is associated with adverse events and mortality. Whilst postulated to cause/exacerbate orthostatic hypotension (OH), the exact relationship between antipsychotic use and OH has never been explored in AD-a group who are particularly vulnerable to neuro-cardiovascular instability and adverse effects of medication on orthostatic blood pressure (BP) behaviour. METHODS: We analysed longitudinal data from an 18-month trial of Nilvadipine in mild-moderate AD. We assessed the effect of long-term antipsychotic use (for the entire 18-month study duration) on orthostatic BP phenotypes measured on eight occasions, in addition to the relationship between antipsychotic use, BP phenotypes and incident falls. RESULTS: Of 509 older adults with AD (aged 72.9 ± 8.3 years, 61.9% female), 10.6% (n = 54) were prescribed a long-term antipsychotic. Over 18 months, long-term antipsychotic use was associated with a greater likelihood of experiencing sit-to-stand OH (ssOH) (OR: 1.21; 1.05-1.38, p = 0.009) which persisted on covariate adjustment. Following adjustment for important clinical confounders, both antipsychotic use (IRR: 1.80, 1.11-2.92, p = 0.018) and ssOH (IRR: 1.44, 1.00-2.06, p = 0.048) were associated with a greater risk of falls/syncope over 18 months in older adults with mild-moderate AD. CONCLUSION: Even in mild-to-moderate AD, long-term antipsychotic use was associated with ssOH. Both antipsychotic use and ssOH were associated with a greater risk of incident falls/syncope over 18 months. Further attention to optimal prescribing interventions in this cohort is warranted and may involve screening older adults with AD prescribed antipsychotics for both orthostatic symptoms and falls.


Assuntos
Doença de Alzheimer , Antipsicóticos , Hipotensão Ortostática , Idoso , Feminino , Humanos , Masculino , Acidentes por Quedas/prevenção & controle , Doença de Alzheimer/complicações , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/epidemiologia , Antipsicóticos/efeitos adversos , Hipotensão Ortostática/tratamento farmacológico , Hipotensão Ortostática/epidemiologia , Hipotensão Ortostática/complicações , Síncope/complicações , Idoso de 80 Anos ou mais
6.
Neurobiol Aging ; 134: 94-105, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38043161

RESUMO

Studies examining the relationships between chronic inflammation, cognitive function and cognitive decline in older adults have yielded conflicting results. In a large cohort of older adults free from established dementia (n = 3270; 73.1 ± 7.9 years; 68.4% female), we evaluated the cross-sectional and longitudinal relationships between serum cytokines (IL-6, IL-10, TNF-α) and both global and domain-specific cognitive performance (Repeatable Battery for Assessment of Neuropsychological Status [RBANS]). Higher IL-6 (OR: 1.33; 1.06, 1.66, p = 0.01), TNF-α (OR: 1.35; 1.09, 1.67, p = 0.01) and IL-6:IL-10 Ratio (OR: 1.43; 1.17, 1.74, p = 0.001) were cross-sectionally associated with impaired global RBANS performance. For specific cognitive domains, greatest effect sizes were observed between higher TNF-α levels and poorer visual-spatial and attention performance. In a subset of participants (n = 725; 69.8 ± 5.5 years; 67.0% female) with repeat assessment performed at a median of 5.4 years, only higher baseline IL-6:IL-10 ratio was associated with impaired incident overall, immediate memory and visual-spatial performance. Associations were stronger in females, but not modified by age or APOE genotype.


Assuntos
Disfunção Cognitiva , Interleucina-10 , Humanos , Feminino , Idoso , Masculino , Interleucina-6 , Fator de Necrose Tumoral alfa , Estudos Transversais , Cognição , Inflamação , Testes Neuropsicológicos
7.
Clin Exp Immunol ; 215(2): 177-189, 2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-37917972

RESUMO

Patients with decompensated liver cirrhosis, in particular those classified as Childs-Pugh class C, are at increased risk of severe coronavirus disease-2019 (COVID-19) upon infection with severe acute respiratory coronavirus 2 (SARS-CoV-2). The biological mechanisms underlying this are unknown. We aimed to examine the levels of serum intrinsic antiviral proteins as well as alterations in the innate antiviral immune response in patients with decompensated liver cirrhosis. Serum from 53 SARS-CoV-2 unexposed and unvaccinated individuals, with decompensated liver cirrhosis undergoing assessment for liver transplantation, were screened using SARS-CoV-2 pseudoparticle and SARS-CoV-2 virus assays. The ability of serum to inhibit interferon (IFN) signalling was assessed using a cell-based reporter assay. Severity of liver disease was assessed using two clinical scoring systems, the Child-Pugh class and the MELD-Na score. In the presence of serum from SARS-CoV-2 unexposed patients with decompensated liver cirrhosis there was no association between SARS-CoV-2 pseudoparticle infection or live SARS-CoV-2 virus infection and severity of liver disease. Type I IFNs are a key component of the innate antiviral response. Serum from patients with decompensated liver cirrhosis contained elevated levels of auto-antibodies capable of binding IFN-α2b compared to healthy controls. High MELD-Na scores were associated with the ability of these auto-antibodies to neutralize type I IFN signalling by IFN-α2b but not IFN-ß1a. Our results demonstrate that neutralizing auto-antibodies targeting IFN-α2b are increased in patients with high MELD-Na scores. The presence of neutralizing type I IFN-specific auto-antibodies may increase the likelihood of viral infections, including severe COVID-19, in patients with decompensated liver cirrhosis.


Assuntos
COVID-19 , Interferon Tipo I , Hepatopatias , Transplante de Fígado , Humanos , Anticorpos , Cirrose Hepática
8.
BMJ Open ; 13(12): e077772, 2023 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-38070888

RESUMO

INTRODUCTION: Alzheimer's disease and other dementias affect >50 million individuals globally and are characterised by broad clinical and biological heterogeneity. Cohort and biobank studies have played a critical role in advancing the understanding of disease pathophysiology and in identifying novel diagnostic and treatment approaches. However, further discovery and validation cohorts are required to clarify the real-world utility of new biomarkers, facilitate research into the development of novel therapies and advance our understanding of the clinical heterogeneity and pathobiology of neurodegenerative diseases. METHODS AND ANALYSIS: The Tallaght University Hospital Institute for Memory and Cognition Biobank for Research in Ageing and Neurodegeneration (TIMC-BRAiN) will recruit 1000 individuals over 5 years. Participants, who are undergoing diagnostic workup in the TIMC Memory Assessment and Support Service (TIMC-MASS), will opt to donate clinical data and biological samples to a biobank. All participants will complete a detailed clinical, neuropsychological and dementia severity assessment (including Addenbrooke's Cognitive Assessment, Repeatable Battery for Assessment of Neuropsychological Status, Clinical Dementia Rating Scale). Participants undergoing venepuncture/lumbar puncture as part of the clinical workup will be offered the opportunity to donate additional blood (serum/plasma/whole blood) and cerebrospinal fluid samples for longitudinal storage in the TIMC-BRAiN biobank. Participants are followed at 18-month intervals for repeat clinical and cognitive assessments. Anonymised clinical data and biological samples will be stored securely in a central repository and used to facilitate future studies concerned with advancing the diagnosis and treatment of neurodegenerative diseases. ETHICS AND DISSEMINATION: Ethical approval has been granted by the St. James's Hospital/Tallaght University Hospital Joint Research Ethics Committee (Project ID: 2159), which operates in compliance with the European Communities (Clinical Trials on Medicinal Products for Human Use) Regulations 2004 and ICH Good Clinical Practice Guidelines. Findings using TIMC-BRAiN will be published in a timely and open-access fashion.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doenças Neurodegenerativas , Humanos , Bancos de Espécimes Biológicos , Doença de Alzheimer/diagnóstico , Envelhecimento , Cognição , Doenças Neurodegenerativas/diagnóstico , Hospitais , Disfunção Cognitiva/diagnóstico
10.
BMC Neurol ; 23(1): 289, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532979

RESUMO

BACKGROUND: Over 55 million adults are living with dementia globally, which is projected to reach 157 million by 2050. Mild cognitive impairment (MCI), a syndrome of memory impairment with intact activities of daily living, may precede dementia by several years. Around 5-15% of individuals with MCI convert to dementia annually. Novel treatments which delay progression of MCI to dementia are urgently needed. Transcutaneous vagal nerve stimulation (tVNS) is a non-invasive neuromodulation technique that targets the vagus nerve. Importantly, tVNS has been shown to improve cognition in healthy volunteers, but has not been extensively examined as a potential therapeutic approach in MCI. VINCI-AD will examine the safety and feasibility of tVNS in older adults with MCI. DESIGN: VINCI-AD is an investigator-led, single-site, single-blind, sham-controlled crossover pilot study which aims to assess the safety and feasibility of tVNS in 40 participants with amnestic MCI. All participants will attend for three consecutive study visits during which they will be randomised to receive no stimulation (baseline), active tVNS stimulation (stimulation at cymba conchae of left ear) or sham tVNS stimulation (at earlobe). Safety will be primarily assessed by ascertainment of adverse events. Further safety assessment will examine the impact of acute tVNS on subjective (orthostatic symptoms), peripheral (finometry-based blood pressure) and central (assessed via Near Infrared Spectroscopy [NIRS]) haemodynamic responses to active stand. Feasibility will be determined using a custom-designed occupational assessment of device usability. Exploratory secondary analysis in VINCI-AD will examine the potential impact of acute tVNS on associative memory, spatial memory and inhibitory control to inform sample size estimates for future trials of tVNS in older adults with MCI. DISCUSSION: VINCI-AD will report on the safety (adverse events/haemodynamic responses to active stand) and feasibility of tVNS as a potential therapeutic option in MCI. Detailed reporting of study eligibility and completion rates will be reported. Exploratory analysis will examine the potential cognitive benefits of acute tVNS on cognitive function in MCI to report potential effect sizes that may inform future clinical trials in this cohort. TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT05514756 . Trial Registration Number NCT05514756 (24th August 2022 for this protocol, version 1.0.).


Assuntos
Disfunção Cognitiva , Demência , Estimulação do Nervo Vago , Idoso , Humanos , Atividades Cotidianas , Disfunção Cognitiva/terapia , Estudos de Viabilidade , Projetos Piloto , Método Simples-Cego , Nervo Vago/fisiologia , Estimulação do Nervo Vago/efeitos adversos , Estimulação do Nervo Vago/métodos
12.
J Transl Med ; 21(1): 437, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37407981

RESUMO

BACKGROUND: Mucopolysaccharidosis IIIC (MPSIIIC) is one of four Sanfilippo diseases sharing clinical symptoms of severe cognitive decline and shortened lifespan. The missing enzyme, heparan sulfate acetyl-CoA: α-glucosaminide-N-acetyltransferase (HGSNAT), is bound to the lysosomal membrane, therefore cannot cross the blood-brain barrier or diffuse between cells. We previously demonstrated disease correction in MPSIIIC mice using an Adeno-Associated Vector (AAV) delivering HGSNAT via intraparenchymal brain injections using an AAV2 derived AAV-truetype (AAV-TT) serotype with improved distribution over AAV9. METHODS: Here, intraparenchymal AAV was delivered in sheep using catheters or Hamilton syringes, placed using Brainlab cranial navigation for convection enhanced delivery, to reduce proximal vector expression and improve spread. RESULTS: Hamilton syringes gave improved AAV-GFP distribution, despite lower vector doses and titres. AAV-TT-GFP displayed moderately better transduction compared to AAV9-GFP but both serotypes almost exclusively transduced neurons. Functional HGSNAT enzyme was detected in 24-37% of a 140g gyrencephalic sheep brain using AAV9-HGSNAT with three injections in one hemisphere. CONCLUSIONS: Despite variabilities in volume and titre, catheter design may be critical for efficient brain delivery. These data help inform a clinical trial for MPSIIIC.


Assuntos
Mucopolissacaridose III , Animais , Acetiltransferases/genética , Acetiltransferases/metabolismo , Encéfalo , Dependovirus/genética , Modelos Animais de Doenças , Vetores Genéticos , Heparitina Sulfato/metabolismo , Mucopolissacaridoses/genética , Mucopolissacaridoses/terapia , Mucopolissacaridose III/genética , Mucopolissacaridose III/metabolismo , Mucopolissacaridose III/terapia , Ovinos , Terapia Genética
13.
Geriatrics (Basel) ; 8(4)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37489323

RESUMO

Apathy is a complex multi-dimensional syndrome that affects up to 70% of individuals with Alzheimer's disease (AD). Whilst many frameworks to define apathy in AD exist, most include loss of motivation or goal-directed behaviour as the central feature. Apathy is associated with significant impact on persons living with AD and their caregivers and is also associated with accelerated cognitive decline across the AD spectrum. Neuroimaging studies have highlighted a key role of fronto-striatial circuitry including the anterior cingulate cortex (ACC), orbito-frontal cortex (OFC) and associated subcortical structures. Importantly, the presence and severity of apathy strongly correlates with AD stage and neuropathological biomarkers of amyloid and tau pathology. Following from neurochemistry studies demonstrating a central role of biogenic amine neurotransmission in apathy syndrome in AD, recent clinical trial data suggest that apathy symptoms may improve following treatment with agents such as methylphenidate-which may have an important role alongside emerging non-pharmacological treatment strategies. Here, we review the diagnostic criteria, rating scales, prevalence, and risk factors for apathy in AD. The underlying neurobiology, neuropsychology and associated neuroimaging findings are reviewed in detail. Finally, we discuss current treatment approaches and strategies aimed at targeting apathy syndrome in AD, highlighting areas for future research and clinical trials in patient cohorts.

14.
PLoS One ; 18(5): e0285529, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37167234

RESUMO

BACKGROUND: In addition to the clear cardiovascular benefit, there has been renewed interest in the potential of statins in the prevention of cognitive impairment and dementia in older adults. However, whether ongoing statin use can delay cognitive decline or dementia progression in those with established Alzheimer dementia, is unclear. METHODS: Using data from NILVAD, we analysed the association between ongoing statin use and cognitive decline (Alzheimer Disease Assessment Scale-Cognitive Subsection [ADAS-Cog])/dementia progression (Clinical Dementia Rating Scale [CDR-Sb]/Disability Assessment for Dementia [DAD]) over 18 months in older adults with mild-moderate AD. Additionally, we assessed the association between ongoing statin use and adverse events in mild-moderate AD. RESULTS: Over one-third (34.9%) of 510 older adults with mild-moderate AD (aged: 72.9 years; 61.9% female) used a statin for the 18-month study duration. Statin use was not associated with the rate of cognitive decline (ß: -0.67; 95% CI: -1.71, 0.36, p = 0.20) or dementia progression (ß: -0.34; 95% CI -0.71, 0.02; p = 0.07 for CDR-Sb/ ß: -2.00; -5.70, 1.70; p = 0.29 for DAD). Further, ongoing statin use was not associated with adverse events, serious adverse events, unscheduled GP visits, or unscheduled hospitalisation. CONCLUSION: Ongoing statin use was not associated with cognitive decline or dementia progression in mild-moderate AD. Similarly, use was not associated with adverse events including abnormal liver function tests or falls. Whilst safe in those with AD, the current results suggest ongoing statin use does not delay cognitive decline or clinical progression in established AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Inibidores de Hidroximetilglutaril-CoA Redutases , Feminino , Humanos , Idoso , Masculino , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/psicologia , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Disfunção Cognitiva/tratamento farmacológico , Estudos Longitudinais , Testes de Estado Mental e Demência , Progressão da Doença
15.
Front Immunol ; 14: 1170012, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063871

RESUMO

Clinical outcomes from infection with SARS-CoV-2, the cause of the COVID-19 pandemic, are remarkably variable ranging from asymptomatic infection to severe pneumonia and death. One of the key drivers of this variability is differing trajectories in the immune response to SARS-CoV-2 infection. Many studies have noted markedly elevated cytokine levels in severe COVID-19, although results vary by cohort, cytokine studied and sensitivity of assay used. We assessed the immune response in acute COVID-19 by measuring 20 inflammatory markers in 118 unvaccinated patients with acute COVID-19 (median age: 70, IQR: 58-79 years; 48.3% female) recruited during the first year of the pandemic and 44 SARS-CoV-2 naïve healthy controls. Acute COVID-19 was associated with marked elevations in nearly all pro-inflammatory markers, whilst eleven markers (namely IL-1ß, IL-2, IL-6, IL-10, IL-18, IL-23, IL-33, TNF-α, IP-10, G-CSF and YKL-40) were associated with disease severity. We observed significant correlations between nearly all markers elevated in those infected with SARS-CoV-2 consistent with widespread immune dysregulation. Principal component analysis highlighted a pro-inflammatory cytokine signature (with strongest contributions from IL-1ß, IL-2, IL-6, IL-10, IL-33, G-CSF, TNF-α and IP-10) which was independently associated with severe COVID-19 (aOR: 1.40, 1.11-1.76, p=0.005), invasive mechanical ventilation (aOR: 1.61, 1.19-2.20, p=0.001) and mortality (aOR 1.57, 1.06-2.32, p = 0.02). Our findings demonstrate elevated cytokines and widespread immune dysregulation in severe COVID-19, adding further evidence for the role of a pro-inflammatory cytokine signature in severe and critical COVID-19.


Assuntos
COVID-19 , Humanos , Feminino , Idoso , Masculino , Citocinas , Interleucina-10 , Interleucina-33 , SARS-CoV-2 , Interleucina-6 , Fator de Necrose Tumoral alfa , Pandemias , Quimiocina CXCL10 , Interleucina-2 , Fator Estimulador de Colônias de Granulócitos
16.
J Virol ; 96(23): e0125022, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36350154

RESUMO

The appearance of new dominant variants of concern (VOC) of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) threatens the global response to the coronavirus disease 2019 (COVID-19) pandemic. Of these, the alpha variant (also known as B.1.1.7), which appeared initially in the United Kingdom, became the dominant variant in much of Europe and North America in the first half of 2021. The spike (S) glycoprotein of alpha acquired seven mutations and two deletions compared to the ancestral virus, including the P681H mutation adjacent to the polybasic cleavage site, which has been suggested to enhance S cleavage. Here, we show that the alpha spike protein confers a level of resistance to beta interferon (IFN-ß) in human lung epithelial cells. This correlates with resistance to an entry restriction mediated by interferon-induced transmembrane protein 2 (IFITM2) and a pronounced infection enhancement by IFITM3. Furthermore, the P681H mutation is essential for resistance to IFN-ß and context-dependent resistance to IFITMs in the alpha S. P681H reduces dependence on endosomal cathepsins, consistent with enhanced cell surface entry. However, reversion of H681 does not reduce cleaved spike incorporation into particles, indicating that it exerts its effect on entry and IFN-ß downstream of furin cleavage. Overall, we suggest that, in addition to adaptive immune escape, mutations associated with VOC may well also confer a replication and/or transmission advantage through adaptation to resist innate immune mechanisms. IMPORTANCE Accumulating evidence suggests that variants of concern (VOC) of SARS-CoV-2 evolve to evade the human immune response, with much interest focused on mutations in the spike protein that escape from antibodies. However, resistance to the innate immune response is essential for efficient viral replication and transmission. Here, we show that the alpha (B.1.1.7) VOC of SARS-CoV-2 is substantially more resistant to type I interferons than the parental Wuhan-like virus. This correlates with resistance to the antiviral protein IFITM2 and enhancement by its paralogue IFITM3. The key determinant of this is a proline-to-histidine change at position 681 in S adjacent to the furin cleavage site, which in the context of the alpha spike modulates cell entry pathways of SARS-CoV-2. Reversion of the mutation is sufficient to restore interferon and IFITM2 sensitivity, highlighting the dynamic nature of the SARS CoV-2 as it adapts to both innate and adaptive immunity in the humans.


Assuntos
COVID-19 , Interferon Tipo I , Humanos , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Furina/metabolismo , Interferon Tipo I/genética , Interferon Tipo I/metabolismo , Linhagem Celular , Mutação , Proteínas de Membrana/metabolismo , Proteínas de Ligação a RNA/metabolismo
17.
Chem Commun (Camb) ; 58(92): 12803-12806, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36263488

RESUMO

The role of low-frequency (terahertz) vibrational motions on charge carrier dynamics in organic semiconductors (OSCs) is becoming well-known, and efforts are underway to rationally design new materials to mitigate these detrimental effects. However, most efforts have focused on stabilizing the fused-ring semiconducting 'core', often by functionalizing with various side-groups, yet questions regarding the role of such modifications on electron-phonon couplings are still outstanding. In this work, the influence of thiophene rings σ-bonded directly to the π-conjugated cores is explored. The manner in which these groups alter low-frequency vibrational, and resulting electronic, dynamics is quantified using a theoretical approach employing fully-periodic density functional theory (DFT) simulations. Ultimately, these results showcase how the equilibrium geometry and corresponding electronic structure are directly related to detrimental electron-phonon coupling, which have important implications for the design of improved organic optoelectronic materials.

18.
Front Immunol ; 13: 1021351, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36311713

RESUMO

Midlife Type 2 Diabetes Mellitus (T2DM) is associated with an increased risk of Alzheimer Disease (AD) in later life, with altered inflammatory responses postulated as key pathological drivers. Previous studies have demonstrated increased responsiveness to NLR family pyrin domain containing 3 (NLRP3) inflammasome agonists, both in individuals with untreated T2DM in addition to those with established AD. We hypothesised that peripheral NLRP3 inflammasome responses may be altered during the early stages of T2DM-related cognitive dysfunction. Here, we assessed the relationship between NLPR3 responses in peripheral blood mononuclear cells (including to Aß-42, the putative pathogenic protein in AD) and neuropsychological performance in uncomplicated midlife T2DM to identify early signatures of immune dysregulation which may predispose to later cognitive decline. We recruited a cross-sectional cohort of middle-aged adults with uncomplicated T2DM and matched Healthy Controls (HCs) for comprehensive neuropsychological assessment and in vitro PBMC responses to a range of NLRP3 agonists were assessed. T2DM was associated with subtle decrements on neuropsychological tests of delayed memory and executive function (both p<0.05). Overall, there were no differences between T2DM and HCs in immune responses induced by NLRP3 agonists. Further, we observed no relationship between the subtle neuropsychological decrements observed in T2DM and PBMC responsiveness to NLRP3 agonists. Our data suggests that peripheral NLRP3 inflammasome response dysregulation may not play a role in the early stages of cognitive dysfunction in midlife T2DM. Further longitudinal studies are warranted to examine the contribution of peripheral NLRP3 responses towards disease pathology and as cognitive decline accelerates in T2DM.


Assuntos
Doença de Alzheimer , Diabetes Mellitus Tipo 2 , Adulto , Humanos , Pessoa de Meia-Idade , Doença de Alzheimer/metabolismo , Estudos Transversais , Inflamassomos/metabolismo , Leucócitos Mononucleares/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
19.
Sensors (Basel) ; 22(15)2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35957266

RESUMO

Type 2 Diabetes Mellitus (T2DM) in midlife is associated with a greater risk of dementia in later life. Both gait speed and spatiotemporal gait characteristics have been associated with later cognitive decline in community-dwelling older adults. Thus, the assessment of gait characteristics in uncomplicated midlife T2DM may be important in selecting-out those with T2DM at greatest risk of later cognitive decline. We assessed the relationship between Inertial Motion Unit (IMUs)-derived gait characteristics and cognitive function assessed via Montreal Cognitive Assessment (MoCA)/detailed neuropsychological assessment battery (CANTAB) in middle-aged adults with and without uncomplicated T2DM using both multivariate linear regression and a neural network approach. Gait was assessed under (i) normal walking, (ii) fast (maximal) walking and (iii) cognitive dual-task walking (reciting alternate letters of the alphabet) conditions. Overall, 138 individuals were recruited (n = 94 with T2DM; 53% female, 52.8 ± 8.3 years; n = 44 healthy controls, 43% female, 51.9 ± 8.1 years). Midlife T2DM was associated with significantly slower gait velocity on both slow and fast walks (both p < 0.01) in addition to a longer stride time and greater gait complexity during normal walk (both p < 0.05). Findings persisted following covariate adjustment. In analyzing cognitive performance, the strongest association was observed between gait velocity and global cognitive function (MoCA). Significant associations were also observed between immediate/delayed memory performance and gait velocity. Analysis using a neural network approach did not outperform multivariate linear regression in predicting cognitive function (MoCA) from gait velocity. Our study demonstrates the impact of uncomplicated T2DM on gait speed and gait characteristics in midlife, in addition to the striking relationship between gait characteristics and global cognitive function/memory performance in midlife. Further studies are needed to evaluate the longitudinal relationship between midlife gait characteristics and later cognitive decline, which may aid in selecting-out those with T2DM at greatest-risk for preventative interventions.


Assuntos
Diabetes Mellitus Tipo 2 , Idoso , Cognição , Feminino , Marcha , Humanos , Masculino , Pessoa de Meia-Idade , Caminhada , Velocidade de Caminhada
20.
J Am Med Dir Assoc ; 23(9): 1590-1602, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35922016

RESUMO

Older adults in nursing homes are at greatest risk of morbidity and mortality from SARS-CoV-2 infection. Nursing home residents constituted one-third to more than half of all deaths during the early waves of the COVID-19 pandemic. Following this, widespread adaptation of infection prevention and control measures and the supply and use of personal protective equipment resulted in a significant decrease in nursing home infections and deaths. For nursing homes, the most important determinant of experiencing a SARS-CoV-2 outbreak in the first instance appears to be community-transmission levels (particularly with variants of concern), although nursing home size and quality, for-profit status, and sociodemographic characteristics are also important. Use of visitation bans, imposed to reduce the impact of COVID-19 on residents, must be delicately balanced against their impact on resident, friend or family, and staff well-being. The successful rollout of primary vaccination has resulted in a sharp decrease in morbidity and mortality from SARS-CoV-2 in nursing homes. However, emerging evidence suggests that vaccine efficacy may wane over time, and the use of a third or additional vaccine "booster" doses in nursing home residents restores protection afforded by primary vaccination. Ongoing monitoring of vaccine efficacy in terms of infection, morbidity, and mortality is crucial in this vulnerable group in informing ongoing SARS-CoV-2 vaccine boosting strategies. Here, we detail the impact of SARS-CoV-2 on nursing home residents and discuss important considerations in the management of nursing home SARS-CoV-2 outbreaks. We additionally examine the use of testing strategies, nonpharmacologic outbreak control measures and vaccination strategies in this cohort. Finally, the impact of SARS-CoV-2 on the sector is reflected on as we emphasize the need for adoption of universal standards of medical care and integration with wider public health infrastructure in nursing homes in order to provide a safe and effective long-term care sector.


Assuntos
COVID-19 , Idoso , Vacinas contra COVID-19 , Humanos , Assistência de Longa Duração , Casas de Saúde , Pandemias/prevenção & controle , SARS-CoV-2
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