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1.
BMC Nurs ; 23(1): 623, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39238014

RESUMO

BACKGROUND: The nursing workforce comprises multiple generations, each with unique values, beliefs, and expectations that can influence communication, work ethic, and professional relationships. In Qatar, the generational gap between nurses and nurse managers poses challenges to effective communication and teamwork, impacting job satisfaction and patient outcomes. AIM: This study investigates the generational gap between nurses and nurse managers in Qatar, aiming to identify strategies to enhance collaboration and create a positive work environment. METHODS: A qualitative research design was used, involving semi-structured interviews with 20 participants, including frontline nurses and senior nurse managers. Participants were purposively sampled to represent different generations. Data were collected through face-to-face and virtual interviews, then transcribed and thematically analyzed. FINDINGS: Four key themes emerged: Optimizing the Work Environment: Older generations preferred transformational and situational leadership, while younger nurses valued respect, teamwork, accountability, and professionalism. Strengthening Work Atmosphere through Communication and values: Older nurses favored face-to-face communication, while younger nurses preferred digital tools. Cultivating Respect and Empathy: Younger nurses emphasized fairness in assignments and promotions, while older nurses focused on empathy and understanding. Dynamic Enhancement of Healthcare Systems: Younger nurses were more adaptable to technology and professional development, while older nurses prioritized clinical care and patient outcomes. CONCLUSION: The study reveals significant generational differences in leadership preferences, communication styles, and adaptability to technology. Addressing these gaps through effective leadership, ongoing education, and open communication can improve job satisfaction and patient care.

2.
J Extracell Vesicles ; 13(7): e12476, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38978287

RESUMO

The current study analyzed the intersecting biophysical, biochemical, and functional properties of extracellular particles (EPs) with the human immunodeficiency virus type-1 (HIV-1) beyond the currently accepted size range for HIV-1. We isolated five fractions (Frac-A through Frac-E) from HIV-infected cells by sequential differential ultracentrifugation (DUC). All fractions showed a heterogeneous size distribution with median particle sizes greater than 100 nm for Frac-A through Frac-D but not for Frac-E, which contained small EPs with an average size well below 50 nm. Synchronized and released cultures contained large infectious EPs in Frac-A, with markers of amphisomes and viral components. Additionally, Frac-E uniquely contained EPs positive for CD63, HSP70, and HIV-1 proteins. Despite its small average size, Frac-E contained membrane-protected viral integrase, detectable only after SDS treatment, indicating that it is enclosed in vesicles. Single particle analysis with dSTORM further supported these findings as CD63, HIV-1 integrase, and the viral surface envelope (Env) glycoprotein (gp) colocalized on the same Frac-E particles. Surprisingly, Frac-E EPs were infectious, and infectivity was significantly reduced by immunodepleting Frac-E with anti-CD63, indicating the presence of this protein on the surface of infectious small EPs in Frac-E. To our knowledge, this is the first time that extracellular vesicle (EV) isolation methods have identified infectious small HIV-1 particles (smHIV-1) that are under 50 nm. Collectively, our data indicate that the crossroads between EPs and HIV-1 potentially extend beyond the currently accepted biophysical properties of HIV-1, which may have further implications for viral pathogenesis.


Assuntos
Vesículas Extracelulares , Infecções por HIV , HIV-1 , Humanos , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/virologia , Infecções por HIV/virologia , Infecções por HIV/metabolismo , Vírion/metabolismo , Ultracentrifugação/métodos , Linfócitos T/virologia , Linfócitos T/metabolismo , Tetraspanina 30/metabolismo , Tamanho da Partícula
3.
Br J Nurs ; 33(11): S4-S10, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38850138

RESUMO

HIV in the UK is concentrated in a few key populations, and African migrants are among them. To date, there has been no documented record of the personal experiences of this group to accompany the significant amount of epidemiological data on these communities. There is no record celebrating the contribution, resilience and lived experience of Africans living with HIV in the UK, their allies and their response to the epidemic. A group of African women who are long-standing HIV activists and advocates, much respected for their leadership within the HIV community, considered that it was important to capture and tell these stories to ensure they were accurately recorded in the history of HIV. Their experience spans the story of the African community's experience of HIV in the UK. They formed a steering group and the project aimed to showcase 40 stories to coincide with the 40th anniversary of HIV in 2021.


Assuntos
Infecções por HIV , Migrantes , Humanos , Infecções por HIV/psicologia , Infecções por HIV/etnologia , Migrantes/psicologia , Reino Unido , Feminino , População Negra/psicologia , África/etnologia
4.
Bioorg Chem ; 150: 107589, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38941696

RESUMO

Extracellular vesicles (EVs) appear to play an important role in intercellular communication in various physiological processes and pathological conditions such as cancer. Like enveloped viruses, EVs can transport their contents into the nucleus of recipient cells, and a new intracellular pathway has been described to explain the nuclear shuttling of EV cargoes. It involves a tripartite protein complex consisting of vesicle-associated membrane protein-associated protein A (VAP-A), oxysterol-binding protein (OSBP)-related protein-3 (ORP3) and late endosome-associated Rab7 allowing late endosome entry into the nucleoplasmic reticulum. Rab7 binding to ORP3-VAP-A complex can be blocked by the FDA-approved antifungal drug itraconazole. Here, we design a new series of smaller triazole derivatives, which lack the dioxolane moiety responsible for the antifungal function, acting on the hydrophobic sterol-binding pocket of ORP3 and evaluate their structure-activity relationship through inhibition of VOR interactions and nuclear transfer of EV and HIV-1 cargoes. Our investigation reveals that the most effective compounds that prevent nuclear transfer of EV cargo and productive infection by VSV-G-pseudotyped HIV-1 are those with a side chain between 1 and 4 carbons, linear or branched (methyl) on the triazolone region. These potent chemical drugs could find clinical applications either for nuclear transfer of cancer-derived EVs that impact metastasis or viral infection.


Assuntos
Infecções por HIV , Triazóis , Triazóis/química , Triazóis/farmacologia , Triazóis/síntese química , Humanos , Relação Estrutura-Atividade , Estrutura Molecular , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , HIV-1/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Relação Dose-Resposta a Droga , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia
5.
Qatar Med J ; 2024(1): 12, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38654818

RESUMO

Background: End-stage renal disease (ESRD) poses a significant health challenge, with hemodialysis (HD) being the most prevalent therapy. Patients undergoing HD must comply with a strict therapeutic regimen, including dietary control, fluid restriction, and medication adherence. Successful disease management and improved outcomes rely on patients' involvement and participation in their care. Aim: To identify the factors that hinder or facilitate self-care management (SCM) in HD patients. Methodology: This review followed Whittemore and Knafl's integrative review framework. A comprehensive literature search of articles published between 2017 and 2022 was conducted in CINAHL, Medline, and PubMed using the keywords end-stage renal disease, hemodialysis, self-care management, self-care, and self-management. This search yielded 21 suitable articles for review. Results: SCM is influenced by three main factors: facilitators, barriers, and outcomes. Facilitators of SCM include self-care management interventions, patient knowledge, socio-demographic factors, family support, healthcare professionals, peer support, and psychological factors. Barriers encompass psychological and physical conditions. Outcomes include both physiological and psychological aspects. Conclusion: Understanding the factors influencing SCM in HD patients is vital for developing reliable and effective self-care strategies and interventions to enhance both physical and psychological outcomes.

6.
Cell Commun Signal ; 22(1): 57, 2024 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243233

RESUMO

BACKGROUND: The incidence of melanoma is increasing worldwide. Since metastatic melanoma is highly aggressive, it is important to decipher all the biological aspects of melanoma cells. In this context, we have previously shown that metastatic FEMX-I melanoma cells release small (< 150 nm) extracellular vesicles (EVs) known as exosomes and ectosomes containing the stem (and cancer stem) cell antigenic marker CD133. EVs play an important role in intercellular communication, which could have a micro-environmental impact on surrounding tissues. RESULTS: We report here a new type of large CD133+ EVs released by FEMX-I cells. Their sizes range from 2 to 6 µm and they contain lipid droplets and mitochondria. Real-time video microscopy revealed that these EVs originate from the lipid droplet-enriched cell extremities that did not completely retract during the cell division process. Once released, they can be taken up by other cells. Silencing CD133 significantly affected the cellular distribution of lipid droplets, with a re-localization around the nuclear compartment. As a result, the formation of large EVs containing lipid droplets was severely compromised. CONCLUSION: Given the biochemical effect of lipid droplets and mitochondria and/or their complexes on cell metabolism, the release and uptake of these new large CD133+ EVs from dividing aggressive melanoma cells can influence both donor and recipient cells, and therefore impact melanoma growth and dissemination.


Assuntos
Vesículas Extracelulares , Melanoma , Humanos , Melanoma/patologia , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/patologia , Vesículas Extracelulares/metabolismo , Divisão Celular , Mitocôndrias/metabolismo
7.
Nat Commun ; 14(1): 4588, 2023 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-37563144

RESUMO

The mechanism of human immunodeficiency virus 1 (HIV-1) nuclear entry, required for productive infection, is not fully understood. Here, we report that in HeLa cells and activated CD4+ T cells infected with HIV-1 pseudotyped with VSV-G and native Env protein, respectively, Rab7+ late endosomes containing endocytosed HIV-1 promote the formation of nuclear envelope invaginations (NEIs) by a molecular mechanism involving the VOR complex, composed of the outer nuclear membrane protein VAP-A, hyperphosphorylated ORP3 and Rab7. Silencing VAP-A or ORP3 and drug-mediated impairment of Rab7 binding to ORP3-VAP-A inhibited the nuclear transfer of the HIV-1 components and productive infection. In HIV-1-resistant quiescent CD4+ T cells, ORP3 was not hyperphosphorylated and neither VOR complex nor NEIs were formed. This new cellular pathway and its molecular players are potential therapeutic targets, perhaps shared by other viruses that require nuclear entry to complete their life cycle.


Assuntos
Infecções por HIV , HIV-1 , Humanos , HIV-1/metabolismo , Células HeLa , Linfócitos T CD4-Positivos/metabolismo , Produtos do Gene env/metabolismo , Proteínas de Membrana/metabolismo
8.
Brain Behav Immun ; 111: 277-291, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37100211

RESUMO

Dysregulated inflammation within the central nervous system (CNS) contributes to neuropathology in infectious, autoimmune, and neurodegenerative disease. With the exception of microglia, major histocompatibility complex (MHC) proteins are virtually undetectable in the mature, healthy central nervous system (CNS). Neurons have generally been considered incapable of antigen presentation, and although interferon gamma (IFN-γ) can elicit neuronal MHC class I (MHC-I) expression and antigen presentation in vitro, it has been unclear whether similar responses occur in vivo. Here we directly injected IFN-γ into the ventral midbrain of mature mice and analyzed gene expression profiles of specific CNS cell types. We found that IFN-γ upregulated MHC-I and associated mRNAs in ventral midbrain microglia, astrocytes, oligodendrocytes, and GABAergic, glutamatergic, and dopaminergic neurons. The core set of IFN-γ-induced genes and their response kinetics were similar in neurons and glia, but with a lower amplitude of expression in neurons. A diverse repertoire of genes was upregulated in glia, particularly microglia, which were the only cells to undergo cellular proliferation and express MHC classII (MHC-II) and associated genes. To determine if neurons respond directly via cell-autonomous IFN-γ receptor (IFNGR) signaling, we produced mutant mice with a deletion of the IFN-γ-binding domain of IFNGR1 in dopaminergic neurons, which resulted in a complete loss of dopaminergic neuronal responses to IFN-γ. Our results demonstrate that IFN-γ induces neuronal IFNGR signaling and upregulation of MHC-I and related genes in vivo, although the expression level is low compared to oligodendrocytes, astrocytes, and microglia.


Assuntos
Interferon gama , Doenças Neurodegenerativas , Camundongos , Animais , Interferon gama/metabolismo , Doenças Neurodegenerativas/metabolismo , Sistema Nervoso Central/metabolismo , Astrócitos/metabolismo , Mesencéfalo/metabolismo
9.
Cancer Cell Int ; 23(1): 77, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37072829

RESUMO

BACKGROUND: Metastatic disease is the major cause of cancer-related deaths. Increasing evidence shows that primary tumor cells can promote metastasis by preparing the local microenvironment of distant organs, inducing the formation of the so-called "pre-metastatic niche". In recent years, several studies have highlighted that among the tumor-derived molecular components active in pre-metastatic niche formation, small extracellular vesicles (sEVs) play a crucial role. Regarding liver metastasis, the ability of tumor-derived sEVs to affect the activities of non-parenchymal cells such as Kupffer cells and hepatic stellate cells is well described, while the effects on hepatocytes, the most conspicuous and functionally relevant hepatic cellular component, remain unknown. METHODS: sEVs isolated from SW480 and SW620 CRC cells and from clinical samples of CRC patients and healthy subjects were used to treat human healthy hepatocytes (THLE-2 cells). RT-qPCR, Western blot and confocal microscopy were applied to investigate the effects of this treatment. RESULTS: Our study shows for the first time that TGFß1-carrying CRC_sEVs impair the morphological and functional properties of healthy human hepatocytes by triggering their TGFß1/SMAD-dependent EMT. These abilities of CRC_sEVs were further confirmed by evaluating the effects elicited on hepatocytes by sEVs isolated from plasma and biopsies from CRC patients. CONCLUSIONS: Since it is known that EMT of hepatocytes leads to the formation of a fibrotic environment, a well-known driver of metastasis, these results suggest that CRC_sEV-educated hepatocytes could have an active and until now neglected role during liver metastasis formation.

10.
Cells ; 11(16)2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-36010551

RESUMO

Intercellular communication between cancer cells themselves or with healthy cells in the tumor microenvironment and/or pre-metastatic sites plays an important role in cancer progression and metastasis. In addition to ligand-receptor signaling complexes, extracellular vesicles (EVs) are emerging as novel mediators of intercellular communication both in tissue homeostasis and in diseases such as cancer. EV-mediated transfer of molecular activities impacting morphological features and cell motility from highly metastatic SW620 cells to non-metastatic SW480 cells is a good in vitro example to illustrate the increased malignancy of colorectal cancer leading to its transformation and aggressive behavior. In an attempt to intercept the intercellular communication promoted by EVs, we recently developed a monovalent Fab fragment antibody directed against human CD9 tetraspanin and showed its effectiveness in blocking the internalization of melanoma cell-derived EVs and the nuclear transfer of their cargo proteins into recipient cells. Here, we employed the SW480/SW620 model to investigate the anti-cancer potential of the anti-CD9 Fab antibody. We first demonstrated that most EVs derived from SW620 cells contain CD9, making them potential targets. We then found that the anti-CD9 Fab antibody, but not the corresponding divalent antibody, prevented internalization of EVs from SW620 cells into SW480 cells, thereby inhibiting their phenotypic transformation, i.e., the change from a mesenchymal-like morphology to a rounded amoeboid-like shape with membrane blebbing, and thus preventing increased cell migration. Intercepting EV-mediated intercellular communication in the tumor niche with an anti-CD9 Fab antibody, combined with direct targeting of cancer cells, could lead to the development of new anti-cancer therapeutic strategies.


Assuntos
Neoplasias do Colo , Vesículas Extracelulares , Comunicação Celular , Neoplasias do Colo/patologia , Vesículas Extracelulares/metabolismo , Humanos , Fragmentos Fab das Imunoglobulinas/metabolismo , Tetraspanina 29/metabolismo , Microambiente Tumoral
11.
Brain Commun ; 4(2): fcac048, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35350555

RESUMO

Progressive cognitive decline in Alzheimer's disease correlates closely with the spread of tau protein aggregation across neural networks of the cortical mantle. We tested the hypothesis that heritable factors may influence the rate of propagation of tau pathology across brain regions in a model system, taking advantage of well-defined genetically diverse background strains in mice. We virally expressed human tau locally in the hippocampus and the entorhinal cortex neurons and monitored the cell-to-cell tau protein spread by immunolabelling. Interestingly, some strains showed more tau spreading than others while tau misfolding accumulated at the same rate in all tested mouse strains. Genetic factors may contribute to tau pathology progression across brain networks, which could help refine mechanisms underlying tau cell-to-cell transfer and accumulation, and potentially provide targets for understanding patient-to-patient variability in the rate of disease progression in Alzheimer's disease.

12.
Sci Rep ; 11(1): 19718, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34611233

RESUMO

In patients with acute ischemic stroke, pial collaterals play a key role in limiting neurological disability by maintaining blood flow to ischemic penumbra. We hypothesized that patient with poor pial collaterals will have greater corneal nerve and endothelial cell abnormalities. In a cross-sectional study, 35 patients with acute ischemic stroke secondary to middle cerebral artery (MCA) occlusion with poor (n = 12) and moderate-good (n = 23) pial collaterals and 35 healthy controls underwent corneal confocal microscopy and quantification of corneal nerve and endothelial cell morphology. In patients with MCA stroke, corneal nerve fibre length (CNFL) (P < 0.001), corneal nerve fibre density (CNFD) (P = 0.025) and corneal nerve branch density (CNBD) (P = 0.002) were lower compared to controls. Age, BMI, cholesterol, triglycerides, HDL, LDL, systolic blood pressure, NIHSS and endothelial cell parameters did not differ but mRS was higher (p = 0.023) and CNFL (p = 0.026) and CNBD (p = 0.044) were lower in patients with poor compared to moderate-good collaterals. CNFL and CNBD distinguished subjects with poor from moderate-good pial collaterals with an AUC of 72% (95% CI 53-92%) and 71% (95% CI 53-90%), respectively. Corneal nerve loss is greater in patients with poor compared to moderate-good pial collaterals and may act as a surrogate marker for pial collateral status in patients with ischemic stroke.


Assuntos
Biomarcadores , Circulação Cerebrovascular , Circulação Colateral , Córnea/inervação , AVC Isquêmico/complicações , AVC Isquêmico/diagnóstico , Adulto , Idoso , Estudos de Casos e Controles , Córnea/patologia , Células Endoteliais/metabolismo , Feminino , Humanos , AVC Isquêmico/etiologia , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
13.
J Extracell Vesicles ; 10(10): e12132, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34429859

RESUMO

Extracellular vesicles (EVs) are mediators of intercellular communication under both healthy and pathological conditions, including the induction of pro-metastatic traits, but it is not yet known how and where functional cargoes of EVs are delivered to their targets in host cell compartments. We have described that after endocytosis, EVs reach Rab7+ late endosomes and a fraction of these enter the nucleoplasmic reticulum and transport EV biomaterials to the host cell nucleoplasm. Their entry therein and docking to outer nuclear membrane occur through a tripartite complex formed by the proteins VAP-A, ORP3 and Rab7 (VOR complex). Here, we report that the antifungal compound itraconazole (ICZ), but not its main metabolite hydroxy-ICZ or ketoconazole, disrupts the binding of Rab7 to ORP3-VAP-A complexes, leading to inhibition of EV-mediated pro-metastatic morphological changes including cell migration behaviour of colon cancer cells. With novel, smaller chemical drugs, inhibition of the VOR complex was maintained, although the ICZ moieties responsible for antifungal activity and interference with intracellular cholesterol distribution were removed. Knowing that cancer cells hijack their microenvironment and that EVs derived from them determine the pre-metastatic niche, small-sized inhibitors of nuclear transfer of EV cargo into host cells could find cancer therapeutic applications, particularly in combination with direct targeting of cancer cells.


Assuntos
Vesículas Extracelulares/efeitos dos fármacos , Vesículas Extracelulares/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo , Itraconazol/farmacologia , Membrana Nuclear/metabolismo , Proteínas de Transporte Vesicular/metabolismo , proteínas de unión al GTP Rab7/metabolismo , Transporte Ativo do Núcleo Celular , Antifúngicos/farmacologia , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Colestenonas/farmacologia , Endocitose , Endossomos/metabolismo , Proteínas de Ligação a Ácido Graxo/química , Humanos , Cetoconazol/farmacologia , Modelos Moleculares , Saponinas/farmacologia , Proteínas de Transporte Vesicular/química , proteínas de unión al GTP Rab7/química
15.
Cells ; 9(9)2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32825578

RESUMO

Extracellular membrane vesicles (EVs) are emerging as new vehicles in intercellular communication, but how the biological information contained in EVs is shared between cells remains elusive. Several mechanisms have been described to explain their release from donor cells and the initial step of their uptake by recipient cells, which triggers a cellular response. Yet, the intracellular routes and subcellular fate of EV content upon internalization remain poorly characterized. This is particularly true for EV-associated proteins and nucleic acids that shuttle to the nucleus of host cells. In this review, we will describe and discuss the release of EVs from donor cells, their uptake by recipient cells, and the fate of their cargoes, focusing on a novel intracellular route wherein small GTPase Rab7+ late endosomes containing endocytosed EVs enter into nuclear envelope invaginations and deliver their cargo components to the nucleoplasm of recipient cells. A tripartite protein complex composed of (VAMP)-associated protein A (VAP-A), oxysterol-binding protein (OSBP)-related protein-3 (ORP3), and Rab7 is essential for the transfer of EV-derived components to the nuclear compartment by orchestrating the particular localization of late endosomes in the nucleoplasmic reticulum.


Assuntos
Transporte Biológico/fisiologia , Comunicação Celular/fisiologia , Endossomos/metabolismo , Vesículas Extracelulares/metabolismo , Humanos
16.
Medicine (Baltimore) ; 99(28): e20694, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32664066

RESUMO

INTRODUCTION: Recurrent ischemic strokes (IS) make up to one-third of all strokes. Nine out of 10 strokes are due to modifiable risk factors. Thus, it seems that standard management strategies of modifiable risk factors are yet to improve. Hence, we planned a randomized controlled trial assessing nurses or pharmacists-led aggressive control of comorbidities and their prognostic impact on IS and transient ischemic attacks (TIA). METHODS/DESIGN: Prospective study to optimize the health of patients with TIAs and stroke admitted to the Hamad General Hospital (PROMOTE HEALTH) is an assessor-blinded, open-label, randomized, two-arm, controlled trial. Eligible patients have IS or TIA, and an additional modifiable risk factor (Hypertension or dyslipidemia) attending the stroke ward or clinic at the Weill Cornell-affiliated Hamad General Hospital. Stroke specialists will offer the control group the currently practiced best risk factor management strategies. Whereas, in the intervention arm, with the assistance of a nurse and a pharmacist, we will make aggressive attempts to meet targets of defined risk factors. The primary outcomes are the mean difference in blood pressure (BP) and low-density lipoprotein. Whereas myocardial infarction, recurrent stroke events, and mortality serve as the study's secondary outcomes. We require 200 patients per study arm to achieve a power of 80% and an alpha level of <0.05. The Medical Research Center and the Institutional Review Board have approved the study, and it was prospectively registered in a trial registry. DISCUSSION: A significant proportion of strokes are due to modifiable preventable risk factors. Despite having the right preventive strategies aimed at mitigating these risk factors, a sizeable proportion of strokes are due to recurring events. This prompted the medical community to evaluate aggressive means of addressing these risk factors. The nurse or pharmacist-led management of comorbidities has been proven to be of value in the management of diabetes and hypertension. It will be of value to demonstrate the effectiveness of utilizing this additional task force in aggressively managing IS or TIA patients with an overarching goal of improving their prognosis. If our intervention proves to be efficacious, this would have a substantial impact on the current stroke practices and guidelines. Additionally, it will invite further research in the area. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov NCT02868723, last updated on September 2018.


Assuntos
Ataque Isquêmico Transitório/prevenção & controle , Acidente Vascular Cerebral/prevenção & controle , Humanos , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Prevenção Secundária
17.
Nat Med ; 26(8): 1256-1263, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32572268

RESUMO

Alzheimer's disease (AD) causes unrelenting, progressive cognitive impairments, but its course is heterogeneous, with a broad range of rates of cognitive decline1. The spread of tau aggregates (neurofibrillary tangles) across the cerebral cortex parallels symptom severity2,3. We hypothesized that the kinetics of tau spread may vary if the properties of the propagating tau proteins vary across individuals. We carried out biochemical, biophysical, MS and both cell- and animal-based-bioactivity assays to characterize tau in 32 patients with AD. We found striking patient-to-patient heterogeneity in the hyperphosphorylated species of soluble, oligomeric, seed-competent tau. Tau seeding activity correlates with the aggressiveness of the clinical disease, and some post-translational modification (PTM) sites appear to be associated with both enhanced seeding activity and worse clinical outcomes, whereas others are not. These data suggest that different individuals with 'typical' AD may have distinct biochemical features of tau. These data are consistent with the possibility that individuals with AD, much like people with cancer, may have multiple molecular drivers of an otherwise common phenotype, and emphasize the potential for personalized therapeutic approaches for slowing clinical progression of AD.


Assuntos
Doença de Alzheimer/genética , Disfunção Cognitiva/genética , Agregação Patológica de Proteínas/genética , Proteínas tau/genética , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Disfunção Cognitiva/patologia , Feminino , Heterogeneidade Genética , Humanos , Masculino , Pessoa de Meia-Idade , Emaranhados Neurofibrilares/genética , Emaranhados Neurofibrilares/metabolismo , Emaranhados Neurofibrilares/patologia , Fosforilação , Agregação Patológica de Proteínas/patologia , Índice de Gravidade de Doença
18.
Nature ; 577(7790): 399-404, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31915375

RESUMO

Alzheimer's disease is an incurable neurodegenerative disorder in which neuroinflammation has a critical function1. However, little is known about the contribution of the adaptive immune response in Alzheimer's disease2. Here, using integrated analyses of multiple cohorts, we identify peripheral and central adaptive immune changes in Alzheimer's disease. First, we performed mass cytometry of peripheral blood mononuclear cells and discovered an immune signature of Alzheimer's disease that consists of increased numbers of CD8+ T effector memory CD45RA+ (TEMRA) cells. In a second cohort, we found that CD8+ TEMRA cells were negatively associated with cognition. Furthermore, single-cell RNA sequencing revealed that T cell receptor (TCR) signalling was enhanced in these cells. Notably, by using several strategies of single-cell TCR sequencing in a third cohort, we discovered clonally expanded CD8+ TEMRA cells in the cerebrospinal fluid of patients with Alzheimer's disease. Finally, we used machine learning, cloning and peptide screens to demonstrate the specificity of clonally expanded TCRs in the cerebrospinal fluid of patients with Alzheimer's disease to two separate Epstein-Barr virus antigens. These results reveal an adaptive immune response in the blood and cerebrospinal fluid in Alzheimer's disease and provide evidence of clonal, antigen-experienced T cells patrolling the intrathecal space of brains affected by age-related neurodegeneration.


Assuntos
Doença de Alzheimer/imunologia , Linfócitos T CD8-Positivos/imunologia , Líquido Cefalorraquidiano/imunologia , Idoso , Sequência de Aminoácidos , Estudos de Coortes , Humanos , Memória Imunológica , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T/química , Receptores de Antígenos de Linfócitos T/imunologia , Análise de Sequência de Proteína
19.
Int J Stroke ; 15(1): 85-89, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30789323

RESUMO

BACKGROUND: Atrial fibrillation is an important risk factor for stroke but there are limited data on atrial fibrillation-related stroke from the Middle East. METHODS: We interrogated the Qatar Stroke Database to establish the occurrence, clinical features, and outcomes of atrial fibrillation-related stroke at Hamad General Hospital, the sole provider of acute stroke care in Qatar. RESULTS: A total of 4079 patients (81.4% male, mean age 55.4 ± 13.3 years) were enrolled in the stroke database between January 2014 and 21 October 2017. Atrial fibrillation was present in 260 (6.4%) patients, of whom 106 (2.6%) had newly diagnosed atrial fibrillation. The National Institute of Health Stroke Scale (NIHSS) was significantly higher (7.9 + 7.0 (median 6; IQR 11) vs. 5.9 + 6.4 (median 4; IQR 6), P < 0.001) in atrial fibrillation patients. The modified Rankin Score (mRS) (P < 0.001) and mortality at 90-day follow-up (P = 0.002) were significantly higher in atrial fibrillation compared to non-atrial fibrillation stroke patients. CONCLUSION: We demonstrate a low rate of atrial fibrillation and stroke in Qatar, perhaps reflecting the relatively young age of these patients. Atrial fibrillation-related strokes had higher admission NIHSS, greater disability, and higher mortality at 90 days when compared to non-atrial fibrillation strokes.


Assuntos
Fibrilação Atrial/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Fibrilação Atrial/diagnóstico , Comorbidade , Bases de Dados Factuais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Catar/epidemiologia , Acidente Vascular Cerebral/diagnóstico
20.
Front Neurol ; 10: 251, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30941096

RESUMO

Stroke attacks were found to be present at a younger age in patients from Southeast Asia (SE) and the Middle East (ME) resident in the state of Qatar. Extracellular vesicles (EVs), which are small membrane vesicles with pro-thrombotic properties, may contribute to the high risk of stroke in this population. Thus, total and cell-specific medium size EVs were counted by flow cytometry in platelet-free plasma from healthy volunteers and patients with transient ischemic attacks (TIA) and acute ischemic stroke (AIS) from SE and ME. Acutely, within 48 h of attacks, there was an increase in total endothelial EVs in TIA (6.73 ± 1.77; P = 0.0156; n = 21) and AIS (11.23 ± 1.95; P = 0.0007; n = 66) patients compared to controls (2.04 ± 0.78; n = 24). Similar increases were also evident in EVs originating from platelets, erythrocytes, granulocytes, and leukocytes. Compared to controls, there was also an increase in EVs derived from activated endothelial cells, platelets, granulocytes, leukocytes, and pro-coagulant EVs (Annexin V+) at 5 and 30-days following the acute events, while a decrease was observed in erythrocyte-derived EVs. This is the first study characterizing EVs in TIA and AIS patients from ME and SE showing an increase in EVs associated with endothelial and platelet cell activation, which may contribute to the elevated risk of stroke at a younger age in this population.

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