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1.
Acta Neuropathol ; 145(1): 29-48, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36357715

RESUMO

Epitranscriptomic regulation adds a layer of post-transcriptional control to brain function during development and adulthood. The identification of RNA-modifying enzymes has opened the possibility of investigating the role epitranscriptomic changes play in the disease process. NOP2/Sun RNA methyltransferase 2 (NSun2) is one of the few known brain-enriched methyltransferases able to methylate mammalian non-coding RNAs. NSun2 loss of function due to autosomal-recessive mutations has been associated with neurological abnormalities in humans. Here, we show NSun2 is expressed in adult human neurons in the hippocampal formation and prefrontal cortex. Strikingly, we unravel decreased NSun2 protein expression and an increased ratio of pTau/NSun2 in the brains of patients with Alzheimer's disease (AD) as demonstrated by Western blotting and immunostaining, respectively. In a well-established Drosophila melanogaster model of tau-induced toxicity, reduction of NSun2 exacerbated tau toxicity, while overexpression of NSun2 partially abrogated the toxic effects. Conditional ablation of NSun2 in the mouse brain promoted a decrease in the miR-125b m6A levels and tau hyperphosphorylation. Utilizing human induced pluripotent stem cell (iPSC)-derived neuronal cultures, we confirmed NSun2 deficiency results in tau hyperphosphorylation. We also found that neuronal NSun2 levels decrease in response to amyloid-beta oligomers (AßO). Notably, AßO-induced tau phosphorylation and cell toxicity in human neurons could be rescued by overexpression of NSun2. Altogether, these results indicate that neuronal NSun2 deficiency promotes dysregulation of miR-125b and tau phosphorylation in AD and highlights a novel avenue for therapeutic targeting.


Assuntos
Doença de Alzheimer , Células-Tronco Pluripotentes Induzidas , MicroRNAs , Camundongos , Animais , Humanos , Adulto , Metiltransferases/genética , Fosforilação/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , MicroRNAs/genética , Proteínas tau/metabolismo , Mamíferos/metabolismo
2.
Mol Psychiatry ; 27(6): 2813-2820, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35365809

RESUMO

Late-onset Alzheimer's disease (LOAD) is significantly more frequent in Hispanics than in non-Hispanic Whites. Ancestry may explain these differences across ethnic groups. To this end, we studied a large cohort of Caribbean Hispanics (CH, N = 8813) and tested the association between Local Ancestry (LA) and LOAD ("admixture mapping") to identify LOAD-associated ancestral blocks, separately for ancestral components (European [EUR], African [AFR], Native American[NA]) and jointly (AFR + NA). Ancestral blocks significant after permutation were fine-mapped employing multi-ethnic whole-exome sequencing (WES) to identify rare variants associated with LOAD (SKAT-O) and replicated in the UK Biobank WES dataset. Candidate genes were validated studying (A) protein expression in human LOAD and control brains; (B) two animal AD models, Drosophila and Zebrafish. In the joint AFR + NA model, we identified four significant ancestral blocks located on chromosomes 1 (p value = 8.94E-05), 6 (p value = 8.63E-05), 21 (p value = 4.64E-05) and 22 (p value = 1.77E-05). Fine-mapping prioritized the GCAT gene on chromosome 22 (SKAT-O p value = 3.45E-05) and replicated in the UK Biobank (SKAT-O p value = 0.05). In LOAD brains, a decrease of 28% in GCAT protein expression was observed (p value = 0.038), and GCAT knockdown in Amyloid-ß42 Drosophila exacerbated rough eye phenotype (68% increase, p value = 4.84E-09). In zebrafish, gcat expression increased after acute amyloidosis (34%, p value = 0.0049), and decreased upon anti-inflammatory Interleukin-4 (39%, p value = 2.3E-05). Admixture mapping uncovered genomic regions harboring new LOAD-associated loci that might explain the observed different frequency of LOAD across ethnic groups. Our results suggest that the inflammation-related activity of GCAT is a response to amyloid toxicity, and reduced GCAT expression exacerbates AD pathology.


Assuntos
Doença de Alzheimer , Etnicidade , Doença de Alzheimer/genética , Animais , Região do Caribe , Drosophila , Humanos , Polimorfismo de Nucleotídeo Único/genética , Peixe-Zebra
3.
Neurobiol Dis ; 170: 105752, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35569721

RESUMO

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease placing a great burden on people living with it, carers and society. Yet, the underlying patho-mechanisms remain unknown and treatments limited. To better understand the molecular changes associated with AD, genome-wide association studies (GWAS) have identified hundreds of candidate genes linked to the disease, like the receptor tyrosine kinase EphA1. However, demonstration of whether and how these genes cause pathology is largely lacking. Here, utilising fly genetics, we generated the first Drosophila model of human wild-type and P460L mutant EphA1 and tested the effects of Eph/ephrin signalling on AD-relevant behaviour and neurophysiology. We show that EphA1 mis-expression did not cause neurodegeneration, shorten lifespan or affect memory but flies mis-expressing the wild-type or mutant receptor were hyper-aroused, had reduced sleep, a stronger circadian rhythm and increased clock neuron activity and excitability. Over-expression of endogenous fly Eph and RNAi-mediated knock-down of Eph and its ligand ephrin affected sleep architecture and neurophysiology. Eph over-expression led to stronger circadian morning anticipation while ephrin knock-down impaired memory. A dominant negative form of the GTPase Rho1, a potential intracellular effector of Eph, led to hyper-aroused flies, memory impairment, less anticipatory behaviour and neurophysiological changes. Our results demonstrate a role of Eph/ephrin signalling in a range of behaviours affected in AD. This presents a starting point for studies into the underlying mechanisms of AD including interactions with other AD-associated genes, like Rho1, Ankyrin, Tau and APP with the potential to identify new targets for treatment.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Doença de Alzheimer/genética , Animais , Drosophila , Efrinas/genética , Estudo de Associação Genômica Ampla , Humanos , Neurofisiologia , Receptores da Família Eph/genética
4.
Dig Dis Sci ; 64(3): 698-707, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30327963

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is the fastest-growing chronic liver disease. However, little is known about NAFLD inpatient resource utilization and clinical outcomes. AIMS: The aim of this study was to quantify inpatient NAFLD encounters using patient-level data over time. METHODS: This was a retrospective analysis of de-identified data for NAFLD patients from the California Patient Discharge Database from 2006 to 2013. NAFLD patients were identified by ICD9 codes 571.40, 571.41, 571.49, 571.8, and 571.9. RESULTS: NAFLD patients (n = 91,558) were predominantly female (60%), 45-65 years old (44%), and white (53%). Inpatient encounters increased from 8153 in 2006 to 16,457 in 2013 and were associated with a 207% increase in charges ($686 million in 2006 to $1.42 billion in 2013) and average increase in charges of 9.8% per year adjusting for inflation. Comorbidities (obesity, diabetes, hyperlipidemia, cardiovascular disease, other cancer, and renal disease) increased significantly over time (all P < 0.05). From 2006 to 2011, there were 11,463 deaths (1849 for liver-related hospitalizations) (mean follow-up 4.00 ± 2.13 years). The most significant predictors of death were age > 75 (aHR 3.9, P < 0.0001), male gender (aHR 1.10, P < 0.0001), white race (aHR 1.2, P < 0.0001), decompensated cirrhosis (aHR 2.1, P < 0.0001), and cancer other than HCC (aHR 3.2, P < 0.0001). Within the liver-related hospitalization cohort, mortality predictors were similar, except for Hispanic race (aHR 0.92, P < 0.0096) and renal disease (aHR 1.50, P < 0.0001). CONCLUSIONS: The number of NAFLD inpatient encounters increased significantly from 2006 to 2013, as did the inflation-adjusted inpatient charges. The most significant predictors of death were non-liver cancers (HR 3.11, P < 0.0001, CI 3.06-3.16) and age > 75 years (HR 3.94, P < 0.0001, HR 3.86-4.03).


Assuntos
Efeitos Psicossociais da Doença , Gastos em Saúde , Preços Hospitalares , Custos Hospitalares , Pacientes Internados , Hepatopatia Gordurosa não Alcoólica/economia , Hepatopatia Gordurosa não Alcoólica/terapia , Admissão do Paciente/economia , Adolescente , Adulto , Fatores Etários , Idoso , California/epidemiologia , Comorbidade , Bases de Dados Factuais , Feminino , Gastos em Saúde/tendências , Preços Hospitalares/tendências , Custos Hospitalares/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/mortalidade , Admissão do Paciente/tendências , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Adulto Jovem
5.
Exp Dermatol ; 27(5): 449-452, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28453925

RESUMO

The soy isoflavone daidzein is bioconverted to 7,8,4'-trihydroxyisoflavone (7,8,4'-THIF) by microorganisms. Here, we investigated the matrix metalloproteinase (MMP)-1 inhibitory properties of 7,8,4'-THIF that arise through the suppression of UVB-induced MMP-1 expression. 7,8,4'-THIF reduced UVB-induced MMP-1 expression at the transcriptional level in primary human dermal fibroblasts and inhibited UVB-induced transcriptional activity of AP-1, a major activator of MMP-1 expression. Additionally, it was observed that the mitogen-activated protein kinase (MAPK) pathway, a crucial signalling cascade for MMP-1 expression, was suppressed by 7,8,4'-THIF. Protein kinase C iota (PKCι) was suspected to be a direct target of 7,8,4'-THIF. The direct interaction between 7,8,4'-THIF and PKCι was confirmed using pull-down assays and immobilized metal ion affinity-based fluorescence polarization assays. Finally, we observed that 7,8,4'-THIF inhibited UVB-induced MMP-1 expression in a human skin equivalent model. Taken together, these results suggest that 7,8,4'-THIF, a bioconversion product of daidzein, suppresses UVB-induced MMP-1 expression.


Assuntos
Isoenzimas/antagonistas & inibidores , Isoflavonas/farmacologia , Metaloproteinase 1 da Matriz/metabolismo , Proteína Quinase C/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos , Humanos , Envelhecimento da Pele/efeitos dos fármacos , Raios Ultravioleta
6.
Br J Pharmacol ; 181(6): 879-895, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37926507

RESUMO

Intracellular accumulation of hyperphosphorylated misfolded tau proteins are found in many neurodegenerative tauopathies, including Alzheimer's disease (AD). Tau pathology can impact cerebrovascular physiology and function through multiple mechanisms. In vitro and in vivo studies have shown that alterations in the blood-brain barrier (BBB) integrity and function can result in synaptic abnormalities and neuronal damage. In the present review, we will summarize how tau proteostasis dysregulation contributes to vascular dysfunction and, conversely, we will examine the factors and pathways leading to tau pathological alterations triggered by cerebrovascular dysfunction. Finally, we will highlight the role epigenetic and epitranscriptomic factors play in regulating the integrity of the cerebrovascular system and the progression of tauopathy including a few observartions on potential therapeutic interventions. LINKED ARTICLES: This article is part of a themed issue From Alzheimer's Disease to Vascular Dementia: Different Roads Leading to Cognitive Decline. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.6/issuetoc.


Assuntos
Doença de Alzheimer , Tauopatias , Humanos , Doença de Alzheimer/metabolismo , Proteínas tau/metabolismo , Barreira Hematoencefálica/metabolismo , Proteostase
7.
Cell Stem Cell ; 31(5): 676-693.e10, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38626772

RESUMO

Frontotemporal dementia (FTD) is an incurable group of early-onset dementias that can be caused by the deposition of hyperphosphorylated tau in patient brains. However, the mechanisms leading to neurodegeneration remain largely unknown. Here, we combined single-cell analyses of FTD patient brains with a stem cell culture and transplantation model of FTD. We identified disease phenotypes in FTD neurons carrying the MAPT-N279K mutation, which were related to oxidative stress, oxidative phosphorylation, and neuroinflammation with an upregulation of the inflammation-associated protein osteopontin (OPN). Human FTD neurons survived less and elicited an increased microglial response after transplantation into the mouse forebrain, which we further characterized by single nucleus RNA sequencing of microdissected grafts. Notably, downregulation of OPN in engrafted FTD neurons resulted in improved engraftment and reduced microglial infiltration, indicating an immune-modulatory role of OPN in patient neurons, which may represent a potential therapeutic target in FTD.


Assuntos
Demência Frontotemporal , Neurônios , Osteopontina , Proteínas tau , Osteopontina/metabolismo , Osteopontina/genética , Demência Frontotemporal/genética , Demência Frontotemporal/patologia , Demência Frontotemporal/metabolismo , Humanos , Neurônios/metabolismo , Neurônios/patologia , Animais , Proteínas tau/metabolismo , Camundongos , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/patologia , Microglia/metabolismo , Microglia/patologia , Mutação/genética
8.
Front Behav Neurosci ; 15: 634157, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093145

RESUMO

Hyperphosphorylation and the subsequent aggregation of tau protein into neurofibrillary tangles (NFTs) are well-established neuropathological hallmarks of Alzheimer's disease (AD) and associated tauopathies. To further examine the impact and progression of human tau pathology in neurodegenerative contexts, the humanized tau (htau) mouse model was originally created. Despite AD-like tau pathological features recapitulated in the htau mouse model, robustness of behavioral phenotypes has not been fully established. With the ultimate goal of evaluating the htau mouse model as a candidate for testing AD therapeutics, we set out to verify, in-house, the presence of robust, replicable cognitive deficits in the htau mice. The present study shows behavioral data collected from a carefully curated battery of learning and memory tests. Here we report a significant short-term spatial memory deficit in aged htau mice, representing a novel finding in this model. However, we did not find salient impairments in long-term learning and memory previously reported in this mouse model. Here, we attempted to understand the discrepancies in the literature by highlighting the necessity of scrutinizing key procedural differences across studies. Reported cognitive deficits in the htau model may depend on task difficulty and other procedural details. While the htau mouse remains a unique and valuable animal model for replicating late onset AD-like human tau pathology, its cognitive deficits are modest under standard testing conditions. The overarching message is that before using any AD mouse model to evaluate treatment efficacies, it is imperative to first characterize and verify the presence of behavioral deficits in-house.

9.
J Physiol ; 587(Pt 12): 2857-67, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19406876

RESUMO

Experience can shape cortical circuits, especially during critical periods for plasticity. In visual cortex, imbalance of activity from the two eyes during the critical period shifts ocular dominance (OD) towards the more active eye. Inhibitory circuits are crucial in this process: OD plasticity is absent in GAD65KO mice that show diminished inhibition. This defect can be rescued by application of benzodiazepines, which increase GABAergic signalling. However, it is unknown how such changes in inhibition might disrupt and then restore OD plasticity. Since NMDA dependent synaptic plasticity mechanisms are also known to contribute to OD plasticity, we investigated whether NMDA receptor levels and function are also altered in GAD65KO. There are reduced NR2A levels and slower NMDA currents in visual cortex of GAD65KO mice. Application of benzodiazepines, which rescues OD plasticity, also increases NR2A levels. Thus it appears as if OD plasticity can be restored by adding a critical amount of excitatory transmission through NR2A-containing NMDA receptors. Together, these observations can unify competing ideas of how OD plasticity is regulated: changes in either inhibition or excitation would engage homeostatic mechanisms that converge to regulate NMDA receptors, thereby enabling plasticity mechanisms and also ensuring circuit stability.


Assuntos
Dominância Ocular/fisiologia , Glutamato Descarboxilase/genética , Glutamato Descarboxilase/fisiologia , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/fisiologia , Animais , Western Blotting , Densitometria , Diazepam/farmacologia , Eletrofisiologia , Moduladores GABAérgicos/farmacologia , Hibridização In Situ , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Plasticidade Neuronal/genética , Plasticidade Neuronal/fisiologia , Receptores de GABA/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Córtex Visual/fisiologia
10.
J Microbiol Biotechnol ; 28(4): 588-596, 2018 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-29385666

RESUMO

An endo-ß-1,4-glucanase gene, cel9K, was cloned using the shot-gun method from Paenibacillus sp. X4, which was isolated from alpine soil. The gene was 2,994 bp in length, encoding a protein of 997 amino acid residues with a predicted signal peptide composed of 32 amino acid residues. Cel9K was a multimodular enzyme, and the molecular mass and theoretical pI of the mature Cel9K were 103.5 kDa and 4.81, respectively. Cel9K contains the GGxxDAGD, PHHR, GAxxGG, YxDDI, and EVxxDYN motifs found in most glycoside hydrolase family 9 (GH9). The protein sequence showed the highest similarity (88%) with the cellulase of Bacillus sp. BP23 in comparison to the enzymes with reported properties. The enzyme was purified by chromatography using HiTrap Q, CHT-II, and HiTrap Butyl HP. Using SDS-PAGE/activity staining, the molecular mass of Cel9K was estimated to be 93 kDa, which is a truncated form produced by the proteolytic cleavage of its C-terminus. Cel9K was optimally active at pH 5.5 and 50°C and showed a half-life of 59.2 min at 50°C. The CMCase activity was increased to more than 150% in the presence of 2 mM Na⁺, K⁺, and Ba²âº, but decreased significantly to less than 50% by Mn²âº and Co²âº. The addition of Cel9K to a commercial enzyme set (Celluclast 1.5L + Novozym 188) increased the saccharification of the pretreated reed and rice straw powders by 30.4 and 15.9%, respectively. The results suggest that Cel9K can be used to enhance the enzymatic conversion of lignocellulosic biomass to reducing sugars as an additive.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Celulase/química , Celulase/genética , Celulase/metabolismo , Paenibacillus/enzimologia , Paenibacillus/genética , Motivos de Aminoácidos , Sequência de Aminoácidos , Bacillus/enzimologia , Bacillus/genética , Celulase/isolamento & purificação , Clonagem Molecular , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Cinética , Lignina/metabolismo , Metais/metabolismo , Peso Molecular , Oryza , Sinais Direcionadores de Proteínas , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade por Substrato , Açúcares/metabolismo , Temperatura , Fatores de Tempo
11.
PLoS One ; 12(8): e0181603, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28797080

RESUMO

BACKGROUND: In Myanmar, over five million people are infected with hepatitis B virus (HBV) and hepatitis C virus (HCV). Hepatitis has been a recent focus with the development of a National Strategic Plan on Hepatitis and plans to subsidize HCV treatment. METHODS: During a two-day national liver disease symposium covering HCV, HBV, hepatocellular (HCC), and end-stage liver disease (ESLD), physician surveys were administered using the automated response system (ARS) to assess physician knowledge, perceptions of barriers to screening and treatment, and proposed solutions. Multivariate logistic regression was used to estimate odds ratio (OR) relating demography and practice factors with higher provider knowledge and improvement. RESULTS: One hundred two physicians attending from various specialty areas (31.0% specializing in gastroenterology/hepatology and/or infectious disease) were of mixed gender (46.8% male), were younger than or equal to 40 years old (51.1% 20 to 40 years), had less experience (61.6% with ≤10 years of medical practice), were from the metropolitan area of Yangon (72.1%), and saw <10 liver disease patients per week (74.3%). The majority of physicians were not comfortable with treating or managing patients with liver disease. The post-test scores demonstrated an improvement in liver disease knowledge (9.0% ± 27.0) compared to the baseline pre-test scores; no variables were associated with significant improvement in hepatitis knowledge. Physicians identified the cost of diagnostic blood tests and treatment as the most significant barrier to treatment. Top solutions proposed were universal screening policies (46%), removal of financial barriers for treatment (29%), patient education (14%) and provider education (11%). CONCLUSIONS: Physician knowledge improved after this symposium, and many other needs were revealed by the physician input on barriers to care and their solutions. These survey results are important in guiding the next steps to improve liver disease management and future medical education efforts in Myanmar.


Assuntos
Carcinoma Hepatocelular/terapia , Gerenciamento Clínico , Hepatite Viral Humana/terapia , Neoplasias Hepáticas/terapia , Médicos , Adulto , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/economia , Carcinoma Hepatocelular/epidemiologia , Feminino , Custos de Cuidados de Saúde , Hepacivirus/isolamento & purificação , Hepatite B/diagnóstico , Hepatite B/economia , Hepatite B/epidemiologia , Hepatite B/terapia , Vírus da Hepatite B/isolamento & purificação , Hepatite C/diagnóstico , Hepatite C/economia , Hepatite C/epidemiologia , Hepatite C/terapia , Hepatite Viral Humana/diagnóstico , Hepatite Viral Humana/economia , Hepatite Viral Humana/epidemiologia , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/economia , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Mianmar/epidemiologia , Razão de Chances , Inquéritos e Questionários , Adulto Jovem
12.
J Clin Hypertens (Greenwich) ; 18(9): 901-6, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26890041

RESUMO

Objective information that can be passively obtained in an ambulatory setting could be potentially useful for determining appropriate care in blood pressure (BP) management. This study utilized digital medicine (DM) prototypes and telemetric data acquisition to directly confirm medication use and to assess habits of daily living in a hypertensive population. Thirty-seven patients (23 men age 62±9 years) used the system for 6 weeks. DM prototypes consisted of valsartan 80 mg or 160 mg placed in a gelatin hemicapsule with an excipient tablet as a "stopper," with a poppy seed-sized ingestible sensor (IS) made of foodstuff on its external surface and capable of creating a biogalvanic current on ingestion to alert a wearable sensor (WS) that was worn on the torso. Passive data collection included IS ingestion dates and times, daily step count, BP, and weight. Automatic short message service (SMS) reminders were sent whenever BP or weight values were not received. Passive detection of DM ingestion was 98% when compared with directly observed dosing. Mean taking and timing adherence rates were 90% and 83%, respectively, and the average step count at a pace of ≥60 steps per minute was 2.0±1.5 h/d. An automatic SMS was sent and 100% confirmed for 251 BP and 14 weight values that were not received. Mild and transient WS-related skin irritation was the most common device-related adverse event. There were no serious or unanticipated adverse events. Ninety percent of patients did not mind swallowing a DM capsule, and 75% had a positive overall experience with the system. Ambulatory evaluation of medication adherence and habits of daily living appear to be feasible and acceptable using DM and passive acquisition of telemetric data.


Assuntos
Monitorização Ambulatorial da Pressão Arterial/instrumentação , Hipertensão/tratamento farmacológico , Adesão à Medicação/estatística & dados numéricos , Idoso , Estudos de Viabilidade , Feminino , Serviços de Assistência Domiciliar , Humanos , Masculino , Pessoa de Meia-Idade , Assistência Centrada no Paciente
13.
BMJ Open Gastroenterol ; 3(1): e000119, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27933202

RESUMO

BACKGROUND: According to Globocan, Mongolia has the highest worldwide hepatocellular carcinoma (HCC) incidence (78.1/100 000, 3.5× higher than China). AIMS AND METHODS: We conducted an anonymous survey of physicians from major provinces who attended an educational liver symposium, analysing their demography, practice, knowledge, perceptions and proposed solutions. Multivariate logistic regression was used to estimate OR relating demography and practice factors with higher provider knowledge and improvement. RESULTS: Of the 121 attendees, 44-95 (36-79%) responded to each question. Most were female (87%), young (79% age <50), subspecialists (81%), university-affiliated (74%), and practised in urban areas (61%). The mean pretest and post-test scores per physician were 60.4±20.4 and 65.6±21.3, with no observed significant predictors for baseline knowledge or improvement. Most (>80%) noted that <50% of patients who need hepatitis or HCC screening receive it. The main perceived barriers to screening were inability to pay for tests, lack of guidelines and poor patient awareness. Hepatitis treatment rates were low; 83% treated hepatitis C virus in <10 patients in the past year, and 86% treated hepatitis B virus in <10 patients/month. Treatment barriers were multifactorial, with cost as a principal barrier. Proposed solutions were universal screening policies (46%), removal of financial barriers (28%) and provider education (20%). CONCLUSIONS: Physicians from major regions of Mongolia noted low screening for viral hepatitis, even lower treatment rates, financial barriers and the need for increased educational efforts. We advocate broad-based medical education tailored to local needs and based on needs assessment and outcome measurements.

14.
Taehan Kanho Hakhoe Chi ; 34(4): 636-45, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15502429

RESUMO

PURPOSE: A natural disaster negatively affects children's emotional and behavioral adjustment. The purpose of this paper was to examine the prevalence, symptoms, and correlates of PTSD after the occurrence of Typhoon Rusa. METHOD: 261 elementary school children living in Kimcheon, which was a devastated rural area in South Korea by Typhoon Rusa, were selected. Data were collected 4 months after the disaster using the PTSD Reaction Index categories recommended by Frederick, severity of PTSD. RESULT: 12.3% of the children had either moderate or severe PTSD symptoms; 22.7% reported mild symptoms; and the remaining 65% had sub-clinical symptoms of PTSD. The most frequent symptom was recurrent fear(67.0%). 13% to 17.2% of children exhibited difficulty in concentration, sleep disturbance, and guilt feeling. The regression model of severity of PTSD was composed of the level of exposure to traumatic experiences, grade in school, gender, negative coping style, and social support, and explained 34.3% for PTSD symptoms. Exposure to traumatic experiences was the strongest factor of all predictors. CONCLUSION: Emotional support from friends and coping style were correlated with PTSD severity. School-based interventions that emphasizes coping with disaster related problems and problem-solving may prove to be useful, and may aid in building close and supportive ties with teachers, classmates, and friends.


Assuntos
Desastres , Psicologia da Criança , Transtornos de Estresse Pós-Traumáticos/etiologia , Adaptação Psicológica , Atitude Frente a Saúde , Criança , Feminino , Amigos/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Coreia (Geográfico)/epidemiologia , Acontecimentos que Mudam a Vida , Masculino , Modelos Psicológicos , Prevalência , Escalas de Graduação Psiquiátrica , Análise de Regressão , Saúde da População Rural , Serviços de Saúde Escolar , Autocuidado/métodos , Autocuidado/psicologia , Índice de Gravidade de Doença , Apoio Social , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Sobreviventes
15.
PLoS One ; 9(10): e110324, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25337699

RESUMO

Human motor neurons derived from embryonic and induced pluripotent stem cells (hESCs and hiPSCs) are a potentially important tool for studying motor neuron survival and pathological cell death. However, their basic survival requirements remain poorly characterized. Here, we sought to optimize a robust survival assay and characterize their response to different neurotrophic factors. First, to increase motor neuron yield, we screened a small-molecule collection and found that the Rho-associated kinase (ROCK) inhibitor Y-27632 enhances motor neuron progenitor proliferation up to 4-fold in hESC and hiPSC cultures. Next, we FACS-purified motor neurons expressing the Hb9::GFP reporter from Y-27632-amplified embryoid bodies and cultured them in the presence of mitotic inhibitors to eliminate dividing progenitors. Survival of these purified motor neurons in the absence of any other cell type was strongly dependent on neurotrophic support. GDNF, BDNF and CNTF all showed potent survival effects (EC(50) 1-2 pM). The number of surviving motor neurons was further enhanced in the presence of forskolin and IBMX, agents that increase endogenous cAMP levels. As a demonstration of the ability of the assay to detect novel neurotrophic agents, Y-27632 itself was found to support human motor neuron survival. Thus, purified human stem cell-derived motor neurons show survival requirements similar to those of primary rodent motor neurons and can be used for rigorous cell-based screening.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/farmacologia , Fator Neurotrófico Ciliar/farmacologia , Células-Tronco Embrionárias/efeitos dos fármacos , Fator Neurotrófico Derivado de Linhagem de Célula Glial/farmacologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Neurônios Motores/efeitos dos fármacos , 1-Metil-3-Isobutilxantina/farmacologia , Amidas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Colforsina/farmacologia , AMP Cíclico/agonistas , AMP Cíclico/metabolismo , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/enzimologia , Expressão Gênica , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/enzimologia , Neurônios Motores/citologia , Neurônios Motores/enzimologia , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Quinases Associadas a rho/antagonistas & inibidores , Quinases Associadas a rho/genética , Quinases Associadas a rho/metabolismo
16.
Toxicol Sci ; 136(2): 443-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24046278

RESUMO

Atopic dermatitis (AD) is a common allergic disease, imposing large social and economic burdens worldwide. Atopic dermatitis is characterized by eczematous skin lesions and immunoglobulin E (IgE) hypersecretion. We investigated the role of JNK1 on the development of AD in mice. The vitamin D3 analogue MC903, a psoriasis therapeutic drug, was used to induce AD-like symptoms in wild-type (WT) and JNK1-/- mice. The symptoms of AD were less severe in JNK1-/- mice compared with WT mice. JNK1-/- mice showed less ear thickening and infiltration of eosinophils and mast cells in AD-like lesions than did WT mice when treated with MC903. MC903-treated JNK1-/- mice also showed significantly lower level of serum IgE, which was elevated in MC903-treated WT mice. Splenocytes isolated from MC903-treated WT and JNK1-/- mice were stimulated with anti-CD3 and anti-CD28 monoclonal antibodies. Splenocytes from JNK1-/- mice produced lower levels of T-helper (Th2) cytokines (interleukin-4 and -13) and transcription factor GATA-binding protein 3, and produced increased levels of the Th1 cytokines interferon-γ and transcription factor T-box expressed in T cells. Our results indicate that JNK1 plays an important role in the pathogenesis of AD and may be a useful target for therapies to ameliorate AD.


Assuntos
Calcitriol/análogos & derivados , Dermatite Atópica/genética , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Animais , Calcitriol/toxicidade , Citocinas/metabolismo , Dermatite Atópica/induzido quimicamente , Feminino , Imunoglobulina E/sangue , Camundongos , Camundongos Knockout , Proteína Quinase 8 Ativada por Mitógeno/genética , Baço/metabolismo
17.
Biochem Pharmacol ; 86(10): 1468-75, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24021351

RESUMO

Rutin is a well-known flavonoid that exists in various natural sources. Accumulative studies have represented the biological effects of rutin, such as anti-oxidative and anti-inflammatory effects. However, the underlying mechanisms of rutin and its direct targets are not understood. We investigated whether rutin reduced B[a]PDE-induced-COX-2 expression. The transactivation of AP-1 and NF-κB were inhibited by rutin. Rutin also attenuated B[a]PDE-induced Raf/MEK/ERK and Akt activation, but had no effect on the phosphorylation of EGFR. An in vitro kinase assay revealed rutin suppressed EGFR kinase activity. We also confirmed direct binding between rutin and EGFR, and found that the binding was regressed by ATP. The EGFR inhibitor also inhibited the B[a]PDE-induced MEK/ERK and Akt signaling pathways and subsequently, suppressed COX-2 expression and promoter activity, in addition to suppressing the transactivation of AP-1 and NF-κB. In EGFR(-/-)mouse embryonic fibroblast cells, B[a]PDE-induced COX-2 expression was also diminished. Collectively, rutin inhibits B[a]PDE-induced COX-2 expression by suppressing the Raf/MEK/ERK and Akt signaling pathways. EGFR appeared to be the direct target of rutin.


Assuntos
7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido/toxicidade , Inibidores de Ciclo-Oxigenase 2/farmacologia , Ciclo-Oxigenase 2/metabolismo , Poluentes Ambientais/toxicidade , Receptores ErbB/metabolismo , Rutina/farmacologia , Animais , Linhagem Celular , Receptores ErbB/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Camundongos , Camundongos Knockout , NF-kappa B/genética , NF-kappa B/metabolismo , Fosforilação , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica , Quinases raf/metabolismo
18.
Cell Rep ; 4(5): 1035-1048, 2013 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-23994478

RESUMO

Differentiation of astrocytes from human stem cells has significant potential for analysis of their role in normal brain function and disease, but existing protocols generate only immature astrocytes. Using early neuralization, we generated spinal cord astrocytes from mouse or human embryonic or induced pluripotent stem cells with high efficiency. Remarkably, short exposure to fibroblast growth factor 1 (FGF1) or FGF2 was sufficient to direct these astrocytes selectively toward a mature quiescent phenotype, as judged by both marker expression and functional analysis. In contrast, tumor necrosis factor alpha and interleukin-1ß, but not FGFs, induced multiple elements of a reactive inflammatory phenotype but did not affect maturation. These phenotypically defined, scalable populations of spinal cord astrocytes will be important both for studying normal astrocyte function and for modeling human pathological processes in vitro.


Assuntos
Astrócitos/citologia , Células-Tronco Neurais/citologia , Neurônios/citologia , Células-Tronco Pluripotentes/citologia , Medula Espinal/citologia , Animais , Astrócitos/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Humanos , Camundongos , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Fenótipo , Células-Tronco Pluripotentes/metabolismo , Medula Espinal/metabolismo
19.
Clin Ther ; 33(5): 598-607, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21665044

RESUMO

BACKGROUND: Specialty drugs are generally defined as high-cost injectable, infused, oral, or inhaled drugs that require close monitoring. Specialty drugs account for an increasing percentage of total drug expenditures, and management of specialty drugs has become a priority. A Central Texas-based integrated health maintenance organization system implemented a specialty drug benefit to manage expensive specialty drug costs. OBJECTIVES: Our objective was to measure and compare the change in adherence and persistence after implementation of copayment increases for select specialty medications used on a long-term basis (at least 2 years). METHODS: Patients who were long-term users of anti-inflammatory, immunosuppressant, cancer, and multiple sclerosis medications were selected. The intervention group consisted of those whose out-of-pocket payment for specialty medications increased, and the control group consisted of those whose out-of-pocket costs did not change. Adherence, defined by proportion of days covered, was measured every 3 months for 12 months before and after the change. Individual growth model analysis evaluated the changes in adherence. Cox regression analysis determined the difference in persistence between groups. RESULTS: There were 178 and 202 patients in the intervention and control groups, respectively. The growth model showed a small but statistically significant decrease in proportion of days covered of 0.040 after copay changes in the intervention versus control group (P < 0.001) for immunosuppressants. The Cox regression analysis indicated a higher probability of intervention patients on anti-inflammatory drugs (hazard ratio [HR] = 2.53; 95% CI, 1.38-4.62) and immunosuppressants (HR = 3.01; 95% CI, 1.20-7.56) would be nonpersistent compared with those in their control groups. CONCLUSIONS: The move to the specialty formulary allows for closer scrutiny of specialty utilization by pharmacists, who actively monitor utilization and access. Despite the minimal adherence decrease and significant persistence changes with certain drug types, the results indicated relatively more stability with specialty drug use than reported with traditional pharmaceuticals.


Assuntos
Dedutíveis e Cosseguros , Tratamento Farmacológico/economia , Sistemas Pré-Pagos de Saúde/organização & administração , Cooperação do Paciente , Humanos , Estudos Longitudinais , Estudos Retrospectivos
20.
Am J Manag Care ; 17(10): 682-90, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22106461

RESUMO

OBJECTIVES: To measure adherence and assess medical utilization among employees enrolled in a disease management (DM) program offering copayment waivers (value-based insurance design [VBID]). STUDY DESIGN: Retrospective matched case control study. METHODS: Cases were defined as those enrolled in DM, of whom 800 received health education mailings (HEMs) and 476 received telephonic nurse counseling (NC). Controls were eligible for the DM program but did not enroll. Cases and controls were matched 1:1 based on propensity score (n = 2552). Adherence, defined by proportion of days covered, was calculated for 4 diseases using incurred drug claims 1 year before and after the DM program was implemented. Unadjusted and adjusted linear regression compared changes in adherence. Costs and utilization were compared at 1 year and 1.5 years after versus 1 year before implementation. RESULTS: Members receiving NC had improved adherence for antihypertensives, diabetes medications, and statins (ß = 0.050, P = .025; ß = 0.108, P < .001; ß = 0.058, P = .017). Members receiving HEMs had improved adherence only for diabetes medications (ß = 0.052, P = .019). Total healthcare costs for NC members increased by $44 ± $467 versus $1861 ± $401 per member per year (PMPY) for controls (P = .003) at 1.5 years post-implementation. Total healthcare costs for HEM members significantly increased ($1261 ± $199 vs $182 ± $181 PMPY for controls; P < .001) at 1.5 years. CONCLUSION: VBID may be effective in improving medication adherence and reducing total healthcare costs when active counseling is provided to high utilizers of care.


Assuntos
Atenção à Saúde/economia , Planos de Assistência de Saúde para Empregados/economia , Custos de Cuidados de Saúde/estatística & dados numéricos , Seguro Saúde/economia , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/economia , Estudos de Casos e Controles , Atenção à Saúde/estatística & dados numéricos , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/economia , Custos de Medicamentos/estatística & dados numéricos , Humanos , Adesão à Medicação/estatística & dados numéricos , Estudos Retrospectivos , Estados Unidos
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