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1.
Cell ; 173(1): 117-129.e14, 2018 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-29570992

RESUMO

Angiogenesis, the formation of new blood vessels by endothelial cells (ECs), is an adaptive response to oxygen/nutrient deprivation orchestrated by vascular endothelial growth factor (VEGF) upon ischemia or exercise. Hypoxia is the best-understood trigger of VEGF expression via the transcription factor HIF1α. Nutrient deprivation is inseparable from hypoxia during ischemia, yet its role in angiogenesis is poorly characterized. Here, we identified sulfur amino acid restriction as a proangiogenic trigger, promoting increased VEGF expression, migration and sprouting in ECs in vitro, and increased capillary density in mouse skeletal muscle in vivo via the GCN2/ATF4 amino acid starvation response pathway independent of hypoxia or HIF1α. We also identified a requirement for cystathionine-γ-lyase in VEGF-dependent angiogenesis via increased hydrogen sulfide (H2S) production. H2S mediated its proangiogenic effects in part by inhibiting mitochondrial electron transport and oxidative phosphorylation, resulting in increased glucose uptake and glycolytic ATP production.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Aminoácidos Sulfúricos/deficiência , Sulfeto de Hidrogênio/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator 4 Ativador da Transcrição/antagonistas & inibidores , Fator 4 Ativador da Transcrição/genética , Aminoácidos Sulfúricos/metabolismo , Animais , Cistationina gama-Liase/metabolismo , Modelos Animais de Doenças , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isquemia/metabolismo , Isquemia/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica , Condicionamento Físico Animal , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética
2.
Nature ; 603(7903): 871-877, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35322231

RESUMO

Neuroanatomists have long speculated that expanded primate brains contain an increased morphological diversity of inhibitory neurons (INs)1, and recent studies have identified primate-specific neuronal populations at the molecular level2. However, we know little about the developmental mechanisms that specify evolutionarily novel cell types in the brain. Here, we reconstruct gene expression trajectories specifying INs generated throughout the neurogenic period in macaques and mice by analysing the transcriptomes of 250,181 cells. We find that the initial classes of INs generated prenatally are largely conserved among mammals. Nonetheless, we identify two contrasting developmental mechanisms for specifying evolutionarily novel cell types during prenatal development. First, we show that recently identified primate-specific TAC3 striatal INs are specified by a unique transcriptional programme in progenitors followed by induction of a distinct suite of neuropeptides and neurotransmitter receptors in new-born neurons. Second, we find that multiple classes of transcriptionally conserved olfactory bulb (OB)-bound precursors are redirected to expanded primate white matter and striatum. These classes include a novel peristriatal class of striatum laureatum neurons that resemble dopaminergic periglomerular cells of the OB. We propose an evolutionary model in which conserved initial classes of neurons supplying the smaller primate OB are reused in the enlarged striatum and cortex. Together, our results provide a unified developmental taxonomy of initial classes of mammalian INs and reveal multiple developmental mechanisms for neural cell type evolution.


Assuntos
Evolução Biológica , Corpo Estriado , Desenvolvimento Embrionário , Macaca , Neurogênese , Neurônios , Bulbo Olfatório , Animais , Corpo Estriado/crescimento & desenvolvimento , Neurônios Dopaminérgicos , Feminino , Macaca/crescimento & desenvolvimento , Mamíferos , Camundongos , Neurogênese/fisiologia , Bulbo Olfatório/fisiologia , Gravidez , Primatas
3.
N Engl J Med ; 388(1): 9-21, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36449413

RESUMO

BACKGROUND: The accumulation of soluble and insoluble aggregated amyloid-beta (Aß) may initiate or potentiate pathologic processes in Alzheimer's disease. Lecanemab, a humanized IgG1 monoclonal antibody that binds with high affinity to Aß soluble protofibrils, is being tested in persons with early Alzheimer's disease. METHODS: We conducted an 18-month, multicenter, double-blind, phase 3 trial involving persons 50 to 90 years of age with early Alzheimer's disease (mild cognitive impairment or mild dementia due to Alzheimer's disease) with evidence of amyloid on positron-emission tomography (PET) or by cerebrospinal fluid testing. Participants were randomly assigned in a 1:1 ratio to receive intravenous lecanemab (10 mg per kilogram of body weight every 2 weeks) or placebo. The primary end point was the change from baseline at 18 months in the score on the Clinical Dementia Rating-Sum of Boxes (CDR-SB; range, 0 to 18, with higher scores indicating greater impairment). Key secondary end points were the change in amyloid burden on PET, the score on the 14-item cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-cog14; range, 0 to 90; higher scores indicate greater impairment), the Alzheimer's Disease Composite Score (ADCOMS; range, 0 to 1.97; higher scores indicate greater impairment), and the score on the Alzheimer's Disease Cooperative Study-Activities of Daily Living Scale for Mild Cognitive Impairment (ADCS-MCI-ADL; range, 0 to 53; lower scores indicate greater impairment). RESULTS: A total of 1795 participants were enrolled, with 898 assigned to receive lecanemab and 897 to receive placebo. The mean CDR-SB score at baseline was approximately 3.2 in both groups. The adjusted least-squares mean change from baseline at 18 months was 1.21 with lecanemab and 1.66 with placebo (difference, -0.45; 95% confidence interval [CI], -0.67 to -0.23; P<0.001). In a substudy involving 698 participants, there were greater reductions in brain amyloid burden with lecanemab than with placebo (difference, -59.1 centiloids; 95% CI, -62.6 to -55.6). Other mean differences between the two groups in the change from baseline favoring lecanemab were as follows: for the ADAS-cog14 score, -1.44 (95% CI, -2.27 to -0.61; P<0.001); for the ADCOMS, -0.050 (95% CI, -0.074 to -0.027; P<0.001); and for the ADCS-MCI-ADL score, 2.0 (95% CI, 1.2 to 2.8; P<0.001). Lecanemab resulted in infusion-related reactions in 26.4% of the participants and amyloid-related imaging abnormalities with edema or effusions in 12.6%. CONCLUSIONS: Lecanemab reduced markers of amyloid in early Alzheimer's disease and resulted in moderately less decline on measures of cognition and function than placebo at 18 months but was associated with adverse events. Longer trials are warranted to determine the efficacy and safety of lecanemab in early Alzheimer's disease. (Funded by Eisai and Biogen; Clarity AD ClinicalTrials.gov number, NCT03887455.).


Assuntos
Doença de Alzheimer , Anticorpos Monoclonais Humanizados , Nootrópicos , Humanos , Atividades Cotidianas , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Cognição/efeitos dos fármacos , Método Duplo-Cego , Nootrópicos/efeitos adversos , Nootrópicos/farmacologia , Nootrópicos/uso terapêutico
4.
Nature ; 578(7796): 621-626, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32051585

RESUMO

The mechanics of the cellular microenvironment continuously modulates cell functions such as growth, survival, apoptosis, differentiation and morphogenesis via cytoskeletal remodelling and actomyosin contractility1-3. Although all of these processes consume energy4,5, it is unknown whether and how cells adapt their metabolic activity to variable mechanical cues. Here we report that the transfer of human bronchial epithelial cells from stiff to soft substrates causes a downregulation of glycolysis via proteasomal degradation of the rate-limiting metabolic enzyme phosphofructokinase (PFK). PFK degradation is triggered by the disassembly of stress fibres, which releases the PFK-targeting E3 ubiquitin ligase tripartite motif (TRIM)-containing protein 21 (TRIM21). Transformed non-small-cell lung cancer cells, which maintain high glycolytic rates regardless of changing environmental mechanics, retain PFK expression by downregulating TRIM21, and by sequestering residual TRIM21 on a stress-fibre subset that is insensitive to substrate stiffness. Our data reveal a mechanism by which glycolysis responds to architectural features of the actomyosin cytoskeleton, thus coupling cell metabolism to the mechanical properties of the surrounding tissue. These processes enable normal cells to tune energy production in variable microenvironments, whereas the resistance of the cytoskeleton in response to mechanical cues enables the persistence of high glycolytic rates in cancer cells despite constant alterations of the tumour tissue.


Assuntos
Microambiente Celular , Citoesqueleto/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Glucose/metabolismo , Glicólise , Dureza , Actinas/metabolismo , Actomiosina/metabolismo , Animais , Brônquios/citologia , Bovinos , Diferenciação Celular , Linhagem Celular , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Fosfofrutoquinases/química , Fosfofrutoquinases/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Ribonucleoproteínas/metabolismo , Fibras de Estresse/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
5.
Annu Rev Cell Dev Biol ; 28: 385-410, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23057744

RESUMO

Efforts in the interdisciplinary field of bioengineering have led to innovative methods for investigating the complexities of cell responses in vitro. These approaches have emphasized the reduction of complex multicomponent cellular microenvironments into distinct individual signals as a means to both (a) better construct mimics of in vivo microenvironments and (b) better deconstruct microenvironments to study them. Microtechnology tools, together with advances in biomaterials, have been fundamental to this progress by enabling the tightly controlled presentation of environmental cues and the improved systematic analysis of cellular perturbations. In this review, we describe bioengineering approaches for controlling and measuring cell-environmental interactions in vitro, including strategies for high-throughput analysis. We also describe the mechanistic insights gained by the use of these novel tools, with associated applications ranging from fundamental biological studies, in vitro modeling of in vivo processes, and cell-based therapies.


Assuntos
Técnicas de Cultura de Células , Engenharia Celular/métodos , Fenômenos Biomecânicos , Materiais Biomiméticos , Reatores Biológicos , Adesão Celular , Humanos , Técnicas Analíticas Microfluídicas , Análise Serial de Tecidos/métodos
6.
Proc Natl Acad Sci U S A ; 120(41): e2308941120, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37782785

RESUMO

Impaired lymphatic drainage and lymphedema are major morbidities whose mechanisms have remained obscure. To study lymphatic drainage and its impairment, we engineered a microfluidic culture model of lymphatic vessels draining interstitial fluid. This lymphatic drainage-on-chip revealed that inflammatory cytokines that are known to disrupt blood vessel junctions instead tightened lymphatic cell-cell junctions and impeded lymphatic drainage. This opposing response was further demonstrated when inhibition of rho-associated protein kinase (ROCK) was found to normalize fluid drainage under cytokine challenge by simultaneously loosening lymphatic junctions and tightening blood vessel junctions. Studies also revealed a previously undescribed shift in ROCK isoforms in lymphatic endothelial cells, wherein a ROCK2/junctional adhesion molecule-A (JAM-A) complex emerges that is responsible for the cytokine-induced lymphatic junction zippering. To validate these in vitro findings, we further demonstrated in a genetic mouse model that lymphatic-specific knockout of ROCK2 reversed lymphedema in vivo. These studies provide a unique platform to generate interstitial fluid pressure and measure the drainage of interstitial fluid into lymphatics and reveal a previously unappreciated ROCK2-mediated mechanism in regulating lymphatic drainage.


Assuntos
Molécula A de Adesão Juncional , Vasos Linfáticos , Linfedema , Quinases Associadas a rho , Animais , Camundongos , Biomimética , Citocinas/metabolismo , Células Endoteliais/metabolismo , Junções Intercelulares , Molécula A de Adesão Juncional/metabolismo , Vasos Linfáticos/metabolismo , Linfedema/genética , Linfedema/metabolismo , Quinases Associadas a rho/metabolismo
7.
PLoS Pathog ; 19(6): e1010478, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37262099

RESUMO

Epstein-Barr virus (EBV) is a ubiquitous human γ-herpesvirus that is causally associated with various malignancies and autoimmune disease. Epstein-Barr Nuclear Antigen 1 (EBNA1) is the viral-encoded DNA binding protein required for viral episome maintenance and DNA replication during latent infection in proliferating cells. EBNA1 is known to be a highly stable protein, but the mechanisms regulating protein stability and how this may be linked to EBNA1 function is not fully understood. Proteomic analysis of EBNA1 revealed interaction with Procollagen Lysine-2 Oxoglutarate 5 Dioxygenase (PLOD) family of proteins. Depletion of PLOD1 by shRNA or inhibition with small molecule inhibitors 2,-2' dipyridyl resulted in the loss of EBNA1 protein levels, along with a selective growth inhibition of EBV-positive lymphoid cells. PLOD1 depletion also caused a loss of EBV episomes from latently infected cells and inhibited oriP-dependent DNA replication. Mass spectrometry identified EBNA1 peptides with lysine hydroxylation at K460 or K461. Mutation of K460, but not K461 abrogates EBNA1-driven DNA replication of oriP, but did not significantly affect EBNA1 DNA binding. Mutations in both K460 and K461 perturbed interactions with PLOD1, as well as decreased EBNA1 protein stability. These findings suggest that PLOD1 is a novel interaction partner of EBNA1 that regulates EBNA1 protein stability and function in viral plasmid replication, episome maintenance and host cell survival.


Assuntos
Infecções por Vírus Epstein-Barr , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase , Humanos , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/genética , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/metabolismo , Infecções por Vírus Epstein-Barr/genética , Herpesvirus Humano 4/genética , Lisina/genética , Proteômica , Replicação do DNA , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Replicação Viral , Estabilidade Proteica , Plasmídeos , Origem de Replicação
8.
Proc Natl Acad Sci U S A ; 119(28): e2115867119, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35763565

RESUMO

Liver regeneration is a well-orchestrated process that is typically studied in animal models. Although previous animal studies have offered many insights into liver regeneration, human biology is less well understood. To this end, we developed a three-dimensional (3D) platform called structurally vascularized hepatic ensembles for analyzing regeneration (SHEAR) to model multiple aspects of human liver regeneration. SHEAR enables control over hemodynamic alterations to mimic those that occur during liver injury and regeneration and supports the administration of biochemical inputs such as cytokines and paracrine interactions with endothelial cells. We found that exposing the endothelium-lined channel to fluid flow led to increased secretion of regeneration-associated factors. Stimulation with relevant cytokines not only amplified the secretory response, but also induced cell-cycle entry of primary human hepatocytes (PHHs) embedded within the device. Further, we identified endothelial-derived mediators that are sufficient to initiate proliferation of PHHs in this context. Collectively, the data presented here underscore the importance of multicellular models that can recapitulate high-level tissue functions and demonstrate that the SHEAR device can be used to discover and validate conditions that promote human liver regeneration.


Assuntos
Células Endoteliais , Hepatócitos , Regeneração Hepática , Fígado , Técnicas de Cultura de Células em Três Dimensões , Citocinas , Humanos , Fígado/irrigação sanguínea , Regeneração Hepática/fisiologia
9.
Proc Natl Acad Sci U S A ; 119(37): e2204179119, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36067305

RESUMO

Alzheimer's disease (AD) is characterized by the accumulation of amyloid-ß plaques and Tau tangles in brain tissues. Recent studies indicate that aberrant splicing and increased level of intron retention is linked to AD pathogenesis. Bioinformatic analysis revealed increased retention of intron 11 at the Tau gene in AD female dorsal lateral prefrontal cortex as compared to healthy controls, an observation validated by quantitative polymerase chain reaction using different brain tissues. Retention of intron 11 introduces a premature stop codon, resulting in the production of truncated Tau11i protein. Probing with customized antibodies designed against amino acids encoded by intron 11 showed that Tau11i protein is more enriched in AD hippocampus, amygdala, parietal, temporal, and frontal lobe than in healthy controls. This indicates that Tau messenger RNA with the retained intron is translated in vivo instead of being subjected to nonsense-mediated decay. Compared to full-length Tau441 isoform, ectopically expressed Tau11i forms higher molecular weight species, is enriched in Sarkosyl-insoluble fraction, and exhibits greater protein stability in cycloheximide assay. Stably expressed Tau11i also shows weaker colocalization with α-tubulin of microtubule network in human mature cortical neurons as compared to Tau441. Endogenous Tau11i is enriched in Sarkosyl-insoluble fraction in AD hippocampus and forms aggregates that colocalize weakly with Tau4R fibril-like structure in AD temporal lobe. The elevated level of Tau11i protein in AD brain tissues tested, coupled with biochemical properties resembling pathological Tau species suggest that retention of intron 11 of Tau gene might be an early biomarker of AD pathology.


Assuntos
Doença de Alzheimer , Proteínas tau , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Biomarcadores/análise , Biomarcadores/metabolismo , Encéfalo/metabolismo , Diagnóstico Precoce , Feminino , Humanos , Íntrons/genética , Placa Amiloide/metabolismo , Proteínas tau/análise , Proteínas tau/genética , Proteínas tau/metabolismo
10.
Mol Cancer ; 23(1): 40, 2024 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-38383439

RESUMO

Finding effective therapeutic targets to treat NRAS-mutated melanoma remains a challenge. Long non-coding RNAs (lncRNAs) recently emerged as essential regulators of tumorigenesis. Using a discovery approach combining experimental models and unbiased computational analysis complemented by validation in patient biospecimens, we identified a nuclear-enriched lncRNA (AC004540.4) that is upregulated in NRAS/MAPK-dependent melanoma, and that we named T-RECS. Considering potential innovative treatment strategies, we designed antisense oligonucleotides (ASOs) to target T-RECS. T-RECS ASOs reduced the growth of melanoma cells and induced apoptotic cell death, while having minimal impact on normal primary melanocytes. Mechanistically, treatment with T-RECS ASOs downregulated the activity of pro-survival kinases and reduced the protein stability of hnRNPA2/B1, a pro-oncogenic regulator of MAPK signaling. Using patient- and cell line- derived tumor xenograft mouse models, we demonstrated that systemic treatment with T-RECS ASOs significantly suppressed the growth of melanoma tumors, with no noticeable toxicity. ASO-mediated T-RECS inhibition represents a promising RNA-targeting approach to improve the outcome of MAPK pathway-activated melanoma.


Assuntos
Melanoma , RNA Longo não Codificante , Humanos , Camundongos , Animais , Melanoma/patologia , RNA Longo não Codificante/genética , Apoptose/genética , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/uso terapêutico , Linhagem Celular Tumoral , Proteínas de Membrana/genética , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo
11.
Adv Funct Mater ; 34(17)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38693998

RESUMO

Although tissue culture plastic has been widely employed for cell culture, the rigidity of plastic is not physiologic. Softer hydrogels used to culture cells have not been widely adopted in part because coupling chemistries are required to covalently capture extracellular matrix (ECM) proteins and support cell adhesion. To create an in vitro system with tunable stiffnesses that readily adsorbs ECM proteins for cell culture, we present a novel hydrophobic hydrogel system via chemically converting hydroxyl residues on the dextran backbone to methacrylate groups, thereby transforming non-protein adhesive, hydrophilic dextran to highly protein adsorbent substrates. Increasing methacrylate functionality increases the hydrophobicity in the resulting hydrogels and enhances ECM protein adsorption without additional chemical reactions. These hydrophobic hydrogels permit facile and tunable modulation of substrate stiffness independent of hydrophobicity or ECM coatings. Using this approach, we show that substrate stiffness and ECM adsorption work together to affect cell morphology and proliferation, but the strengths of these effects vary in different cell types. Furthermore, we reveal that stiffness mediated differentiation of dermal fibroblasts into myofibroblasts is modulated by the substrate ECM. Our material system demonstrates remarkable simplicity and flexibility to tune ECM coatings and substrate stiffness and study their effects on cell function.

12.
J Cardiovasc Electrophysiol ; 35(5): 895-905, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38433304

RESUMO

INTRODUCTION: Cardiac contractility modulation (CCM) is a medical device-based therapy delivering non-excitatory electrical stimulations to the heart to enhance cardiac function in heart failure (HF) patients. The lack of human in vitro tools to assess CCM hinders our understanding of CCM mechanisms of action. Here, we introduce a novel chronic (i.e., 2-day) in vitro CCM assay to evaluate the effects of CCM in a human 3D microphysiological system consisting of engineered cardiac tissues (ECTs). METHODS: Cryopreserved human induced pluripotent stem cell-derived cardiomyocytes were used to generate 3D ECTs. The ECTs were cultured, incorporating human primary ventricular cardiac fibroblasts and a fibrin-based gel. Electrical stimulation was applied using two separate pulse generators for the CCM group and control group. Contractile properties and intracellular calcium were measured, and a cardiac gene quantitative PCR screen was conducted. RESULTS: Chronic CCM increased contraction amplitude and duration, enhanced intracellular calcium transient amplitude, and altered gene expression related to HF (i.e., natriuretic peptide B, NPPB) and excitation-contraction coupling (i.e., sodium-calcium exchanger, SLC8). CONCLUSION: These data represent the first study of chronic CCM in a 3D ECT model, providing a nonclinical tool to assess the effects of cardiac electrophysiology medical device signals complementing in vivo animal studies. The methodology established a standardized 3D ECT-based in vitro testbed for chronic CCM, allowing evaluation of physiological and molecular effects on human cardiac tissues.


Assuntos
Técnicas Eletrofisiológicas Cardíacas , Contração Miocárdica , Miócitos Cardíacos , Contração Miocárdica/genética , Contração Miocárdica/fisiologia , Engenharia Tecidual , Humanos , Miócitos Cardíacos/fisiologia , Células-Tronco Pluripotentes/fisiologia , Perfilação da Expressão Gênica
13.
Phys Biol ; 21(3)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38452380

RESUMO

Understanding the structural and functional development of human-induced pluripotent stem-cell-derived cardiomyocytes (hiPSC-CMs) is essential to engineering cardiac tissue that enables pharmaceutical testing, modeling diseases, and designing therapies. Here we use a method not commonly applied to biological materials, small angle x-ray scattering, to characterize the structural development of hiPSC-CMs within three-dimensional engineered tissues during their preliminary stages of maturation. An x-ray scattering experimental method enables the reliable characterization of the cardiomyocyte myofilament spacing with maturation time. The myofilament lattice spacing monotonically decreases as the tissue matures from its initial post-seeding state over the span of 10 days. Visualization of the spacing at a grid of positions in the tissue provides an approach to characterizing the maturation and organization of cardiomyocyte myofilaments and has the potential to help elucidate mechanisms of pathophysiology, and disease progression, thereby stimulating new biological hypotheses in stem cell engineering.


Assuntos
Células-Tronco Pluripotentes Induzidas , Miofibrilas , Humanos , Raios X , Diferenciação Celular/fisiologia , Miócitos Cardíacos/fisiologia , Células-Tronco Pluripotentes Induzidas/fisiologia , Engenharia Tecidual/métodos
14.
J Natl Compr Canc Netw ; 22(7): 438-446, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-39236750

RESUMO

The NCCN Guidelines for Colorectal Cancer (CRC) Screening describe various colorectal screening modalities as well as recommended screening schedules for patients at average or increased risk of developing sporadic CRC. They are intended to aid physicians with clinical decision-making regarding CRC screening for patients without defined genetic syndromes. These NCCN Guidelines Insights focus on select recent updates to the NCCN Guidelines, including a section on primary and secondary CRC prevention, and provide context for the panel's recommendations regarding the age at which to initiate screening in average-risk individuals and those with increased risk based on personal history of childhood, adolescent, and young adult cancer.


Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Humanos , Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer/normas , Detecção Precoce de Câncer/métodos , Programas de Rastreamento/métodos , Programas de Rastreamento/normas
15.
Cerebrovasc Dis ; 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402856

RESUMO

INTRODUCTION: Reporting of sex and gender analysis in medical research has been shown to improve quality of the science and ensures findings are applicable to women and men. There is conflicting evidence on whether efforts by funding agencies and medical journals to encourage reporting of sex and gender analysis has resulted in tangible improvements. This study mapped the inclusion of sex and gender analysis in stroke and dementia research conducted in the Asia-Pacific region. METHODS: A systematic search for Asia-Pacific stroke and dementia research was conducted in PubMed and papers included from the period 2012 to 2022. Eligible studies were reviewed for inclusion of a primary sex or gender focus and categorized by type of sex and gender analysis. Author gender was determined using an algorithm and its associations with inclusion of sex and gender analysis examined. RESULTS: Total Asia-Pacific publications increased from 109 in 2012 to 313 in 2022, but the rate of studies with a primary sex or gender focus did not increase significantly (R2 = 0.06, F(1,9) = 0.59, p = 0.46). Australia, China, India, Japan and South Korea produced the most publications over the study period and were the only countries with at least 50 publications. The impact of author gender was mixed, with female first authorship associated with inclusion of sex or gender analysis and last female authorship associated with studies having a primary sex or gender focus. CONCLUSIONS: In the Asia-Pacific, brain health research is currently centered around high income countries and efforts are needed to ensure research findings are applicable through out the region. While there was a general increase in brain health publications over the last decade, the rate of sex and gender analysis was unchanged. This demonstrates that even with efforts in some countries in place, there is currently a lack of progress in the Asia-Pacific region to produce more research focusing on sex and gender analysis.

16.
Arterioscler Thromb Vasc Biol ; 43(3): 427-442, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36700429

RESUMO

BACKGROUND: Considerable evidence links dietary salt intake with the development of hypertension, left ventricular hypertrophy, and increased risk of stroke and coronary heart disease. Despite extensive epidemiological and basic science interrogation of the relationship between high salt (HS) intake and blood pressure, it remains unclear how HS impacts endothelial cell (EC) and vascular structure in vivo. This study aims to elucidate HS-induced vascular pathology using a differential systemic decellularization in vivo approach. METHODS: We performed systematic molecular characterization of the endothelial glycocalyx and EC proteomes in mice with HS (8%) diet-induced hypertension versus healthy control animals. Isolation of eGC and EC compartments was achieved using differential systemic decellularization in vivo methodology. Altered protein expression in hypertensive compared to normal mice was characterized by liquid chromatography tandem mass spectrometry. Proteomic results were validated using functional assays, microscopic imaging, and histopathologic evaluation. RESULTS: Proteomic analysis revealed a significant downregulation of eGC and associated proteins in HS diet-induced hypertensive mice (among 1696 proteins identified in this group, 723 were markedly decreased in abundance, while only 168 were increased in abundance. Bioinformatic analysis indicated substantial derangement of the eGC layer, which was subsequently confirmed by fluorescent and electron microscopy assessment of vessel damage ex vivo. In the EC fraction, HS-induced hypertension significantly altered protein mediators of contractility, metabolism, mechanotransduction, renal function, and the coagulation cascade. In particular, we observed dysregulation of integrin subunits α2, α2b, and α5, which was associated with arterial wall inflammation and substantial infiltration of CD68+ monocyte-macrophages. Consequently, HS-induced hypertensive mice also displayed reduced vascular integrity of multiple organs including lungs, kidneys, and heart. CONCLUSIONS: These findings provide novel molecular insight into HS-induced structural changes in eGC and EC composition that may increase cardiovascular risk and potentially guide the development of new diagnostics and therapeutic interventions.


Assuntos
Hipertensão , Cloreto de Sódio na Dieta , Camundongos , Animais , Cloreto de Sódio na Dieta/efeitos adversos , Proteômica , Mecanotransdução Celular , Pressão Sanguínea/fisiologia
17.
Nat Rev Mol Cell Biol ; 18(12): 715, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29093558
18.
BMC Geriatr ; 24(1): 698, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39179981

RESUMO

BACKGROUND: Housing has been associated with dementia risk and disability, but associations of housing with differential patterns of neuropsychiatric symptoms (NPS) among dementia-free older adults remain to be explored. The present study sought to explore the contribution of housing status on NPS and subsyndromes associated with cognitive dysfunction in community-dwelling dementia-free elderly in Singapore. METHODS: A total of 839 dementia-free elderly from the Epidemiology of Dementia in Singapore (EDIS) study aged ≥ 60 were enrolled in the current study. All participants underwent clinical, cognitive, and neuropsychiatric inventory (NPI) assessments. The housing status was divided into three categories according to housing type. Cognitive function was measured by a comprehensive neuropsychological battery. The NPS were assessed using 12-term NPI and were grouped into four clinical subsyndromes: psychosis, hyperactivity, affective, and apathy. Associations of housing with composite and domain-specific Z-scores, as well as NPI scores, were assessed using generalized linear models (GLM). Binary logistic regression models analysed the association of housing with the presence of NPS and significant NPS (NPI total scores ≥ 4). RESULTS: Better housing status (5-room executive apartments, condominium, or private housing) was associated with better NPS (OR = 0.49, 95%CI = 0.24 to 0.98, P < 0.05) and significant NPS profile (OR = 0.20, 95%CI = 0.08 to 0.46, P < 0.01), after controlling for demographics, risk factors, and cognitive performance. Compared with those living in 1-2 room apartments, older adults in better housing had lower total NPI scores (ß=-0.50, 95%CI=-0.95 to -0.04, P = 0.032) and lower psychosis scores (ß=-0.36, 95%CI=-0.66 to -0.05, P = 0.025), after controlling for socioeconomic status (SES) indexes. Subgroup analysis indicated a significant correlation between housing type and NPS in females, those of Malay ethnicity, the more educated, those with lower income, and those diagnosed with cognitive impairment, no dementia (CIND). CONCLUSIONS: Our study showed a protective effect of better housing arrangements on NPS, especially psychosis in a multi-ethnic Asian geriatric population without dementia. The protective effect of housing on NPS was independent of SES and might have other pathogenic mechanisms. Improving housing could be an effective way to prevent neuropsychiatric disturbance among the elderly.


Assuntos
Demência , Humanos , Masculino , Feminino , Idoso , Singapura/epidemiologia , Demência/epidemiologia , Demência/etnologia , Demência/psicologia , Demência/prevenção & controle , Idoso de 80 Anos ou mais , Vida Independente , Habitação , Testes Neuropsicológicos , Pessoa de Meia-Idade , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etnologia , Disfunção Cognitiva/psicologia
19.
BMC Health Serv Res ; 24(1): 1127, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39334395

RESUMO

BACKGROUND: Despite progress in stroke therapy (e.g., revascularisation interventions by thrombolysis and/or thrombectomy, organised stroke care), many stroke survivors will have impairment of neurological function. We aimed to compare the cost-effectiveness of an oral natural formulation, MLC601, versus placebo in functional recovery among subjects receiving standard of care after an ischemic stroke of intermediate severity assessed with NIH Stroke Scale at baseline (b-NIHSS 8-14). METHODS: A Markov cohort model with a 2-year time horizon was developed to simulate patients from a published randomised placebo-controlled clinical trial of MLC601 in their post-stroke functional recovery assessed by modified Rankin Score (mRS), from a health system perspective. Transition probabilities were derived from a multi-centre clinical trial in South East Asia. As cost and utility data were not collected in the trial, therefore we extracted them from the published literature. The main outcomes were incremental cost, incremental quality-adjusted life-year (QALY) gained, and incremental cost-effectiveness ratio (ICER). Besides base-case and sensitivity analyses, we performed subgroup analyses to explore the heterogeneity of patients with poor-prognosis factors (b-NIHSS 10-14, stroke onset to treatment time > 48 h, rehabilitation during first 3 month). All costs are expressed in 2022 Euro and USD, with an annual discount rate of 3% applied to costs and QALYs. RESULTS: Base-case analysis showed that MLC601 was cost-effective compared with placebo, with €5,080 saved and 0.45 QALY gained, resulting in an ICER of -€11,352.50 per QALY gained. Similarly, results from subgroup analyses indicated that the use of MLC601 was a dominant strategy in all subgroups with poor-prognosis factors. Sensitivity analyses revealed the results were robust. CONCLUSION: Compared with placebo on top of standard stroke care, MLC601 was cost-effective in post-stroke functional recovery over two years. Due to the lack of cost and utility data from the study population, the results might not be generalizable to other settings. Further studies with country-specific data are needed to confirm the results of this study. TRIAL REGISTRATION: URL http://www. CLINICALTRIALS: gov . Unique identifier NCT00554723 November 7, 2007.


Assuntos
Análise Custo-Benefício , Cadeias de Markov , Anos de Vida Ajustados por Qualidade de Vida , Recuperação de Função Fisiológica , Acidente Vascular Cerebral , Humanos , Feminino , Masculino , Acidente Vascular Cerebral/tratamento farmacológico , Idoso , Pessoa de Meia-Idade , Medicamentos de Ervas Chinesas
20.
Psychiatry Clin Neurosci ; 78(4): 229-236, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38113307

RESUMO

AIM: Recovery from stroke is adversely affected by neuropsychiatric complications, cognitive impairment, and functional disability. Better knowledge of their mutual relationships is required to inform effective interventions. Network theory enables the conceptualization of symptoms and impairments as dynamic and mutually interacting systems. We aimed to identify interactions of poststroke complications using network analysis in diverse stroke samples. METHODS: Data from 2185 patients were sourced from member studies of STROKOG (Stroke and Cognition Consortium), an international collaboration of stroke studies. Networks were generated for each cohort, whereby nodes represented neuropsychiatric symptoms, cognitive deficits, and disabilities on activities of daily living. Edges characterized associations between them. Centrality measures were used to identify hub items. RESULTS: Across cohorts, a single network of interrelated poststroke complications emerged. Networks exhibited dissociable depression, apathy, fatigue, cognitive impairment, and functional disability modules. Worry was the most central symptom across cohorts, irrespective of the depression scale used. Items relating to activities of daily living were also highly central nodes. Follow-up analysis in two studies revealed that individuals who worried had more densely connected networks than those free of worry (CASPER [Cognition and Affect after Stroke: Prospective Evaluation of Risks] study: S = 9.72, P = 0.038; SSS [Sydney Stroke Study]: S = 13.56, P = 0.069). CONCLUSION: Neuropsychiatric symptoms are highly interconnected with cognitive deficits and functional disabilities resulting from stroke. Given their central position and high level of connectedness, worry and activities of daily living have the potential to drive multimorbidity and mutual reinforcement between domains of poststroke complications. Targeting these factors early after stroke may have benefits that extend to other complications, leading to better stroke outcomes.


Assuntos
Transtornos Cognitivos , Disfunção Cognitiva , Acidente Vascular Cerebral , Humanos , Depressão/psicologia , Atividades Cotidianas/psicologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Transtornos Cognitivos/complicações , Disfunção Cognitiva/complicações , Cognição
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