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1.
Proc Natl Acad Sci U S A ; 121(14): e2308132121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38551841

RESUMO

Tumor necrosis factor (TNF) receptor 1 (TNFR1) plays a pivotal role in mediating TNF induced downstream signaling and regulating inflammatory response. Recent studies have suggested that TNFR1 activation involves conformational rearrangements of preligand assembled receptor dimers and targeting receptor conformational dynamics is a viable strategy to modulate TNFR1 signaling. Here, we used a combination of biophysical, biochemical, and cellular assays, as well as molecular dynamics simulation to show that an anti-inflammatory peptide (FKCRRWQWRMKK), which we termed FKC, inhibits TNFR1 activation allosterically by altering the conformational states of the receptor dimer without blocking receptor-ligand interaction or disrupting receptor dimerization. We also demonstrated the efficacy of FKC by showing that the peptide inhibits TNFR1 signaling in HEK293 cells and attenuates inflammation in mice with intraperitoneal TNF injection. Mechanistically, we found that FKC binds to TNFR1 cysteine-rich domains (CRD2/3) and perturbs the conformational dynamics required for receptor activation. Importantly, FKC increases the frequency in the opening of both CRD2/3 and CRD4 in the receptor dimer, as well as induces a conformational opening in the cytosolic regions of the receptor. This results in an inhibitory conformational state that impedes the recruitment of downstream signaling molecules. Together, these data provide evidence on the feasibility of targeting TNFR1 conformationally active region and open new avenues for receptor-specific inhibition of TNFR1 signaling.


Assuntos
Receptores Tipo I de Fatores de Necrose Tumoral , Transdução de Sinais , Camundongos , Humanos , Animais , Ligantes , Células HEK293 , Fator de Necrose Tumoral alfa/metabolismo , Peptídeos/farmacologia
2.
J Neuroinflammation ; 20(1): 185, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37543564

RESUMO

Microglia are the resident innate immune cells in the brain with a major role in orchestrating immune responses. They also provide a frontline of host defense in the central nervous system (CNS) through their active phagocytic capability. Being a professional phagocyte, microglia participate in phagocytic and autophagic clearance of cellular waste and debris as well as toxic protein aggregates, which relies on optimal lysosomal acidification and function. Defective microglial lysosomal acidification leads to impaired phagocytic and autophagic functions which result in the perpetuation of neuroinflammation and progression of neurodegeneration. Reacidification of impaired lysosomes in microglia has been shown to reverse neurodegenerative pathology in Alzheimer's disease. In this review, we summarize key factors and mechanisms contributing to lysosomal acidification impairment and the associated phagocytic and autophagic dysfunction in microglia, and how these defects contribute to neuroinflammation and neurodegeneration. We further discuss techniques to monitor lysosomal pH and therapeutic agents that can reacidify impaired lysosomes in microglia under disease conditions. Finally, we propose future directions to investigate the role of microglial lysosomal acidification in lysosome-mitochondria crosstalk and in neuron-glia interaction for more comprehensive understanding of its broader CNS physiological and pathological implications.


Assuntos
Doença de Alzheimer , Microglia , Humanos , Microglia/metabolismo , Doenças Neuroinflamatórias , Doença de Alzheimer/metabolismo , Lisossomos/metabolismo , Concentração de Íons de Hidrogênio
3.
Biomacromolecules ; 23(9): 3822-3830, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-35944154

RESUMO

The molecular origin of sickle cell disease (SCD) has been known since 1949, but treatments remain limited. We present the first high-throughput screening (HTS) platform for discovering small molecules that directly inhibit sickle hemoglobin (HbS) oligomerization and improve blood flow, potentially overcoming a long-standing bottleneck in SCD drug discovery. We show that at concentrations far below the threshold for nucleation and rapid polymerization, deoxygenated HbS forms small assemblies of multiple α2ß2 tetramers. Our HTS platform leverages high-sensitivity fluorescence lifetime measurements that monitor these temporally stable prefibrillar HbS oligomers. We show that this approach is sensitive to compounds that inhibit HbS polymerization with or without modulating hemoglobin oxygen binding affinity. We also report the results of a pilot small-molecule screen in which we discovered and validated several novel inhibitors of HbS oligomerization.


Assuntos
Anemia Falciforme , Hemoglobina Falciforme , Anemia Falciforme/tratamento farmacológico , Anemia Falciforme/metabolismo , Descoberta de Drogas , Hemoglobina Falciforme/química , Hemoglobina Falciforme/metabolismo , Hemoglobinas , Humanos , Oxigênio/metabolismo
4.
Alzheimers Dement ; 15(11): 1489-1502, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31653529

RESUMO

OBJECTIVE: Understanding the heterogeneous pathology in Alzheimer's disease and related tauopathies is one of the most urgent and fundamental challenges facing the discovery of novel disease-modifying therapies. Through monitoring ensembles of toxic and nontoxic tau oligomers spontaneously formed in cells, our biosensor technology can identify tool compounds that modulate tau oligomer structure and toxicity, providing much needed insight into the nature and properties of toxic tau oligomers. BACKGROUND: Tauopathies are a group of neurodegenerative disorders characterized by pathologic aggregation of the microtubule binding protein tau. Recent studies suggest that tau oligomers are the primary toxic species in tauopathies. NEW/UPDATED HYPOTHESIS: We hypothesize that tau biosensors capable of monitoring tau oligomer conformation are able to identify tool compounds that modulate the structure and conformation of these tau assemblies, providing key insight into the unique structural fingerprints of toxic tau oligomers. These fingerprints will provide gravely needed biomarker profiles to improve staging of early tauopathy pathology and generate lead compounds for potential new therapeutics. Our time-resolved fluorescence resonance energy transfer biosensors provide us an exquisitely sensitive technique to monitor minute structural changes in monomer and oligomer conformation. In this proof-of-concept study, we identified a novel tool compound, MK-886, which directly binds tau, perturbs the conformation of toxic tau oligomers, and rescues tau-induced cytotoxicity. Furthermore, we show that MK-886 alters the conformation of tau monomer at the proline-rich and microtubule binding regions, stabilizing an on-pathway oligomer. MAJOR CHALLENGES FOR THE HYPOTHESIS: Our approach monitors changes in the ensemble of assemblies that are spontaneously formed in cells but does not specifically isolate or enrich unique toxic tau species. However, time-resolved fluorescence resonance energy transfer does not provide high-resolution, atomic scale information, requiring additional experimental techniques to resolve the structural features stabilized by different tool compounds. LINKAGE TO OTHER MAJOR THEORIES: Our biosensor technology is broadly applicable to other areas of tauopathy therapeutic development. These biosensors can be readily modified for different isoforms of tau, specific post-translational modifications, and familial Alzheimer's disease-associated mutations. We are eager to explore tau interactions with chaperone proteins, monitor cross-reactivity with other intrinsically disordered proteins, and target seeded oligomer pathology.


Assuntos
Doença de Alzheimer/patologia , Biomarcadores/metabolismo , Transferência Ressonante de Energia de Fluorescência , Tauopatias , Proteínas tau/metabolismo , Encéfalo/patologia , Humanos , Indóis
5.
Pharmaceuticals (Basel) ; 17(5)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38794182

RESUMO

Overcoming the blood-brain barrier (BBB) remains a significant hurdle in effective drug delivery to the brain. While the BBB serves as a crucial protective barrier, it poses challenges in delivering therapeutic agents to their intended targets within the brain parenchyma. To enhance drug delivery for the treatment of neurological diseases, several delivery technologies to circumvent the BBB have been developed in the last few years. Among them, nanoparticles (NPs) are one of the most versatile and promising tools. Here, we summarize the characteristics of NPs that facilitate BBB penetration, including their size, shape, chemical composition, surface charge, and importantly, their conjugation with various biological or synthetic molecules such as glucose, transferrin, insulin, polyethylene glycol, peptides, and aptamers. Additionally, we discuss the coating of NPs with surfactants. A comprehensive overview of the common in vitro and in vivo models of the BBB for NP penetration studies is also provided. The discussion extends to discussing BBB impairment under pathological conditions and leveraging BBB alterations under pathological conditions to enhance drug delivery. Emphasizing the need for future studies to uncover the inherent therapeutic properties of NPs, the review advocates for their role beyond delivery systems and calls for efforts translating NPs to the clinic as therapeutics. Overall, NPs stand out as a highly promising therapeutic strategy for precise BBB targeting and drug delivery in neurological disorders.

6.
ACS Nano ; 18(24): 15452-15467, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38830624

RESUMO

Type 2 diabetes (T2D), a prevalent metabolic disorder lacking effective treatments, is associated with lysosomal acidification dysfunction, as well as autophagic and mitochondrial impairments. Here, we report a series of biodegradable poly(butylene tetrafluorosuccinate-co-succinate) polyesters, comprising a 1,4-butanediol linker and varying ratios of tetrafluorosuccinic acid (TFSA) and succinic acid as components, to engineer lysosome-acidifying nanoparticles (NPs). The synthesized NPs are spherical with diameters of ≈100 nm and have low polydispersity and good stability. Notably, TFSA NPs, which are composed entirely of TFSA, exhibit the strongest degradation capability and superior acidifying properties. We further reveal significant downregulation of lysosomal vacuolar (H+)-ATPase subunits, which are responsible for maintaining lysosomal acidification, in human T2D pancreatic islets, INS-1 ß-cells under chronic lipotoxic conditions, and pancreatic tissues of high-fat-diet (HFD) mice. Treatment with TFSA NPs restores lysosomal acidification, autophagic function, and mitochondrial activity, thereby improving the pancreatic function in INS-1 cells and HFD mice with lipid overload. Importantly, the administration of TFSA NPs to HFD mice reduces insulin resistance and improves glucose clearance. These findings highlight the therapeutic potential of lysosome-acidifying TFSA NPs for T2D.


Assuntos
Células Secretoras de Insulina , Lisossomos , Nanopartículas , Lisossomos/metabolismo , Lisossomos/efeitos dos fármacos , Animais , Nanopartículas/química , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Camundongos , Humanos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/patologia , Masculino , Dieta Hiperlipídica , Camundongos Endogâmicos C57BL , Concentração de Íons de Hidrogênio
7.
Bioeng Transl Med ; 8(1): e10350, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36684106

RESUMO

Membrane proteins (MPs) play key roles in cellular signaling pathways and are responsible for intercellular and intracellular interactions. Dysfunctional MPs are directly related to the pathogenesis of various diseases, and they have been exploited as one of the most sought-after targets in the pharmaceutical industry. However, working with MPs is difficult given that their amphiphilic nature requires protection from biological membrane or membrane mimetics. Polymersomes are bilayered nano-vesicles made of self-assembled block copolymers that have been widely used as cell membrane mimetics for MP reconstitution and in engineering of artificial cells. This review highlights the prevailing trend in the application of polymersomes in MP study and drug discovery. We begin with a review on the techniques for synthesis and characterization of polymersomes as well as methods of MP insertion to form proteopolymersomes. Next, we review the structural and functional analysis of the different types of MPs reconstituted in polymersomes, including membrane transport proteins, MP complexes, and membrane receptors. We then summarize the factors affecting reconstitution efficiency and the quality of reconstituted MPs for structural and functional studies. Additionally, we discuss the potential in using proteopolymersomes as platforms for high-throughput screening (HTS) in drug discovery to identify modulators of MPs. We conclude by providing future perspectives and recommendations on advancing the study of MPs and drug development using proteopolymersomes.

8.
Transl Neurodegener ; 12(1): 29, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-37287072

RESUMO

Lysosomal acidification dysfunction has been implicated as a key driving factor in the pathogenesis of neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. Multiple genetic factors have been linked to lysosomal de-acidification through impairing the vacuolar-type ATPase and ion channels on the organelle membrane. Similar lysosomal abnormalities are also present in sporadic forms of neurodegeneration, although the underlying pathogenic mechanisms are unclear and remain to be investigated. Importantly, recent studies have revealed early occurrence of lysosomal acidification impairment before the onset of neurodegeneration and late-stage pathology. However, there is a lack of methods for organelle pH monitoring in vivo and a dearth of lysosome-acidifying therapeutic agents. Here, we summarize and present evidence for the notion of defective lysosomal acidification as an early indicator of neurodegeneration and urge the critical need for technological advancement in developing tools for lysosomal pH monitoring and detection both in vivo and for clinical applications. We further discuss current preclinical pharmacological agents that modulate lysosomal acidification, including small molecules and nanomedicine, and their potential clinical translation into lysosome-targeting therapies. Both timely detection of lysosomal dysfunction and development of therapeutics that restore lysosomal function represent paradigm shifts in targeting neurodegenerative diseases.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , ATPases Vacuolares Próton-Translocadoras , Humanos , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/tratamento farmacológico , Prognóstico , ATPases Vacuolares Próton-Translocadoras/genética , ATPases Vacuolares Próton-Translocadoras/metabolismo , Lisossomos/metabolismo , Concentração de Íons de Hidrogênio
9.
J Int Med Res ; 51(8): 3000605231192779, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37632450

RESUMO

OBJECTIVE: To investigate the association between seasonality and intentional drug overdose (IDO), a commonly seen method of self-harm in daily emergency medicine practice. METHODS: Cases of IDO were retrospectively selected using the International Classification of Diseases (ICD)-10 coding system (codes T36-T50), in patients who attended the Emergency Department of MacKay Memorial Hospital between January 2018 and August 2019. Data regarding age, sex, arrival time, marital status, vital signs, comorbidities, psychiatric history, social conflicts, substance of overdose, and length of hospital stay by season, were analysed using Student's t-test and χ2-test. RESULTS: Of all included cases (n = 196), IDO occurred most frequently in spring (32.1%), particularly in male patients (28/49 male cases). First-time IDO occurred most frequently in spring (51/133 first-time cases) and most spring cases were first-time IDO (51/63 spring cases). Repeat IDO occurred most frequently in autumn (20/63 repeat cases). Female conflict with father and/or boyfriend, and personality disorder in patients who overdosed, showed seasonality with a spring peak. Hospital admission rate was highest in winter (10/45 winter cases [22.2%]). CONCLUSION: Episodes of IDO exhibited seasonality, with a spring peak, particularly for male patients, female patients in conflict with father and/or boyfriend, and those with personality disorder. Clinicians should pay close attention to the abovementioned patient groups.


Assuntos
Overdose de Drogas , Humanos , Feminino , Masculino , Estudos Retrospectivos , Overdose de Drogas/epidemiologia , Serviço Hospitalar de Emergência , Amigos , Hospitais
10.
Brain Sci ; 13(9)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37759919

RESUMO

Data mining involves the computational analysis of a plethora of publicly available datasets to generate new hypotheses that can be further validated by experiments for the improved understanding of the pathogenesis of neurodegenerative diseases. Although the number of sequencing datasets is on the rise, microarray analysis conducted on diverse biological samples represent a large collection of datasets with multiple web-based programs that enable efficient and convenient data analysis. In this review, we first discuss the selection of biological samples associated with neurological disorders, and the possibility of a combination of datasets, from various types of samples, to conduct an integrated analysis in order to achieve a holistic understanding of the alterations in the examined biological system. We then summarize key approaches and studies that have made use of the data mining of microarray datasets to obtain insights into translational neuroscience applications, including biomarker discovery, therapeutic development, and the elucidation of the pathogenic mechanisms of neurodegenerative diseases. We further discuss the gap to be bridged between microarray and sequencing studies to improve the utilization and combination of different types of datasets, together with experimental validation, for more comprehensive analyses. We conclude by providing future perspectives on integrating multi-omics, to advance precision phenotyping and personalized medicine for neurodegenerative diseases.

11.
J Pharm Anal ; 13(8): 836-850, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37719197

RESUMO

Bioinformatic analysis of large and complex omics datasets has become increasingly useful in modern day biology by providing a great depth of information, with its application to neuroscience termed neuroinformatics. Data mining of omics datasets has enabled the generation of new hypotheses based on differentially regulated biological molecules associated with disease mechanisms, which can be tested experimentally for improved diagnostic and therapeutic targeting of neurodegenerative diseases. Importantly, integrating multi-omics data using a systems bioinformatics approach will advance the understanding of the layered and interactive network of biological regulation that exchanges systemic knowledge to facilitate the development of a comprehensive human brain profile. In this review, we first summarize data mining studies utilizing datasets from the individual type of omics analysis, including epigenetics/epigenomics, transcriptomics, proteomics, metabolomics, lipidomics, and spatial omics, pertaining to Alzheimer's disease, Parkinson's disease, and multiple sclerosis. We then discuss multi-omics integration approaches, including independent biological integration and unsupervised integration methods, for more intuitive and informative interpretation of the biological data obtained across different omics layers. We further assess studies that integrate multi-omics in data mining which provide convoluted biological insights and offer proof-of-concept proposition towards systems bioinformatics in the reconstruction of brain networks. Finally, we recommend a combination of high dimensional bioinformatics analysis with experimental validation to achieve translational neuroscience applications including biomarker discovery, therapeutic development, and elucidation of disease mechanisms. We conclude by providing future perspectives and opportunities in applying integrative multi-omics and systems bioinformatics to achieve precision phenotyping of neurodegenerative diseases and towards personalized medicine.

12.
Cancer Biol Ther ; 24(1): 2176692, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36775838

RESUMO

Nimesulide is a nonsteroidal anti-inflammatory drug and a COX-2 inhibitor with antitumor and antiproliferative activities that induces apoptosis in oral, esophagus, breast, and pancreatic cancer cells. Despite being removed from the market due to hepatotoxicity, nimesulide is still an important research tool being used to develop new anticancer drugs. Multiple studies have been done to modify the nimesulide skeleton to develop more potent anticancer agents and related compounds are promising scaffolds for future development. As such, establishing a mechanism of action for nimesulide remains an important part of realizing its potential. Here, we show that nimesulide enhances TRAIL-induced apoptosis in resistant pancreatic cancer cells by promoting clustering of DR5 in the plasma membrane. In this way, nimesulide acts like a related compound, DuP-697, which sensitizes TRAIL-resistant colon cancer cells in a similar manner. Our approach applies a time-resolved FRET-based biosensor that monitors DR5 clustering and conformational states in the plasma membrane. We show that this tool can be used for future high-throughput screens to identify novel, nontoxic small molecule scaffolds to overcome TRAIL resistance in cancer cells.


Assuntos
Inibidores de Ciclo-Oxigenase 2 , Neoplasias Pancreáticas , Humanos , Inibidores de Ciclo-Oxigenase 2/farmacologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Apoptose , Neoplasias Pancreáticas/patologia , Linhagem Celular Tumoral , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Neoplasias Pancreáticas
13.
ACS Bio Med Chem Au ; 3(3): 270-282, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37363080

RESUMO

Tumor necrosis factor (TNF) plays an important role in the pathogenesis of inflammatory and autoimmune diseases such as rheumatoid arthritis and Crohn's disease. The biological effects of TNF are mediated by binding to TNF receptors, TNF receptor 1 (TNFR1), or TNF receptor 2 (TNFR2), and this coupling makes TNFR1-specific inhibition by small-molecule therapies essential to avoid deleterious side effects. Recently, we engineered a time-resolved fluorescence resonance energy transfer biosensor for high-throughput screening of small molecules that modulate TNFR1 conformational states and identified zafirlukast as a compound that inhibits receptor activation, albeit at low potency. Here, we synthesized 16 analogues of zafirlukast and tested their potency and specificity for TNFR1 signaling. Using cell-based functional assays, we identified three analogues with significantly improved efficacy and potency, each of which induces a conformational change in the receptor (as measured by fluorescence resonance energy transfer (FRET) in cells). The best analogue decreased NF-κB activation by 2.2-fold, IκBα efficiency by 3.3-fold, and relative potency by two orders of magnitude. Importantly, we showed that the analogues do not block TNF binding to TNFR1 and that binding to the receptor's extracellular domain is strongly cooperative. Despite these improvements, the best candidate's maximum inhibition of NF-κB is only 63%, leaving room for further improvements to the zafirlukast scaffold to achieve full inhibition and prove its potential as a therapeutic lead. Interestingly, while we find that the analogues also bind to TNFR2 in vitro, they do not inhibit TNFR2 function in cells or cause any conformational changes upon binding. Thus, these lead compounds should also be used as reagents to study conformational-dependent activation of TNF receptors.

14.
Nat Commun ; 14(1): 2573, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37142604

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in the world. High levels of free fatty acids in the liver impair hepatic lysosomal acidification and reduce autophagic flux. We investigate whether restoration of lysosomal function in NAFLD recovers autophagic flux, mitochondrial function, and insulin sensitivity. Here, we report the synthesis of novel biodegradable acid-activated acidifying nanoparticles (acNPs) as a lysosome targeting treatment to restore lysosomal acidity and autophagy. The acNPs, composed of fluorinated polyesters, remain inactive at plasma pH, and only become activated in lysosomes after endocytosis. Specifically, they degrade at pH of ~6 characteristic of dysfunctional lysosomes, to further acidify and enhance the function of lysosomes. In established in vivo high fat diet mouse models of NAFLD, re-acidification of lysosomes via acNP treatment restores autophagy and mitochondria function to lean, healthy levels. This restoration, concurrent with reversal of fasting hyperglycemia and hepatic steatosis, indicates the potential use of acNPs as a first-in-kind therapeutic for NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/metabolismo , Autofagia , Fígado/metabolismo , Lisossomos/metabolismo , Concentração de Íons de Hidrogênio
15.
Biomed Rep ; 16(6): 49, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35620313

RESUMO

Drug overdose is one of the common events encountered in the emergency department (ED). The aim of the present study was to investigate the sex difference and predisposing factors of overdose in the ED. Data of 299 patients with self-poisoning reported at our poison center from January 2018 to August 2019 were retrospectively analyzed. Study cases categorized using the International Classification of Diseases, Tenth Revision coding system, which include codes T36 to T50, were selected. Data were collected including Glasgow Coma Scale scores and vital signs upon arrival (including body temperature, heart rate, systolic blood pressure, and diastolic blood pressure, sex, age, marital status, arrival time, season on admission, previous suicide attempts, psychiatric history, related comorbidities, recent arguments, categories of overdose with or without concurrent ethanol use, length of hospital stay, and survival to discharge) were analyzed. The top three types of substances that were frequently involved in drug overdose were benzodiazepine (42.9%), mixed medications (32.1%), and acetaminophen (6.1%). The 196 enrolled patients were aged 14 to 92 years (mean ± standard deviation, 39.2±18.3), and of these patients, male intentional overdose patients were 8.1 years older than their female counterparts (45.3±19.5 vs. 37.2±17.5, respectively; P<0.05). Most intentional overdose cases occurred during the spring season (n=63, 32.1%), especially in male patients (n=28, 57.1%; P<0.001). Approximately 11.2% (22/196) and 2% (4/196) of the total patients were admitted to the Toxicology ward and intensive care units, respectively. The length of hospital stay was 2±4.1 days. In summary, it is suggested that physicians notify the suicide prevention centers to be on alert for middle-aged men who are facing conflicts, especially during the spring season.

16.
Bioeng Transl Med ; : e10411, 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36248233

RESUMO

In COVID-19, fomite transmission has been shown to be a major route for the spreading of the SARS-CoV-2 virus due to its ability to remain on surfaces for extended durations. Although glove wearing can mitigate the risk of viral transmission especially on high touch points, it is not prevalent due to concerns on diversion of frontline medical resources, cross-contamination, social stigma, as well as discomfort and skin reactions derived from prolonged wearing. In this study, we developed FlexiPalm, a hand-targeted auxiliary personal protective equipment (PPE) against fomite transmission of viruses. FlexiPalm is a unique palmar-side hand protector designed to be skin-conforming and transparent, fabricated from medical-grade polyurethane transparent film material as a base substrate. It serves primarily as a barrier to microbial contamination like conventional gloves, but with augmented comfort and inconspicuousness to encourage a higher public adoption rate. Compared to conventional glove materials, FlexiPalm demonstrated enhanced mechanical durability and breathability, comparable hydrophobicity, and displayed a minimal adsorption of SARS-CoV-2 spike protein and virus-like particles (VLP). Importantly, FlexiPalm was found to bind significantly less viral protein and VLP than artificial human skin, confirming its ability to reduce viral contamination. A pilot study involving participants completing activities of daily living showed a high level of comfort and task completion, illustrating the usability and functionality of FlexiPalm. Moreover, we have demonstrated that surface modification of FlexiPalm with microtextures enables further reduction in viral adsorption, thereby enhancing its functionality. An effective implementation of FlexiPalm will bolster PPE sustainability and lead to a paradigm shift in the global management of COVID-19 and other infectious diseases in general.

17.
Artigo em Inglês | MEDLINE | ID: mdl-35046083

RESUMO

BACKGROUND AND OBJECTIVES: To determine the effects of dimethyl fumarate (DMF) and glatiramer acetate on iron content in chronic active lesions in patients with multiple sclerosis (MS) and in human microglia in vitro. METHODS: This was a retrospective observational study of 34 patients with relapsing-remitting MS and clinically isolated syndrome treated with DMF or glatiramer acetate. Patients had lesions with hyperintense rims on quantitative susceptibility mapping, were treated with DMF or glatiramer acetate (GA), and had a minimum of 2 on-treatment scans. Changes in susceptibility in rim lesions were compared among treatment groups in a linear mixed effects model. In a separate in vitro study, induced pluripotent stem cell-derived human microglia were treated with DMF or GA, and treatment-induced changes in iron content and activation state of microglia were compared. RESULTS: Rim lesions in patients treated with DMF had on average a 2.77-unit reduction in susceptibility per year over rim lesions in patients treated with GA (bootstrapped 95% CI -5.87 to -0.01), holding all other variables constant. Moreover, DMF but not GA reduced inflammatory activation and concomitantly iron content in human microglia in vitro. DISCUSSION: Together, our data indicate that DMF-induced reduction of susceptibility in MS lesions is associated with a decreased activation state in microglial cells. We have demonstrated that a specific disease modifying therapy, DMF, decreases glial activity in chronic active lesions. Susceptibility changes in rim lesions provide an in vivo biomarker for the effect of DMF on microglial activity. CLASSIFICATION OF EVIDENCE: This study provided Class III evidence that DMF is superior to GA in the presence of iron as a marker of inflammation as measured by MRI quantitative susceptibility mapping.


Assuntos
Fumarato de Dimetilo/farmacologia , Acetato de Glatiramer/farmacologia , Imunossupressores/farmacologia , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Doenças Neuroinflamatórias/tratamento farmacológico , Adulto , Células Cultivadas , Feminino , Humanos , Células-Tronco Pluripotentes Induzidas , Masculino , Microglia , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Esclerose Múltipla Recidivante-Remitente/patologia , Doenças Neuroinflamatórias/diagnóstico por imagem , Doenças Neuroinflamatórias/patologia , Estudos Retrospectivos
18.
Artigo em Inglês | MEDLINE | ID: mdl-36041861

RESUMO

The classification of multiple sclerosis (MS) has been established by Lublin in 1996 and revised in 2013. The revision includes clinically isolated syndrome, relapsing-remitting, primary progressive and secondary progressive MS, and has added activity (i.e., formation of white matter lesions or clinical relapses) as a qualifier. This allows for the distinction between active and nonactive progression, which has been shown to be of clinical importance. We propose that a logical extension of this classification is the incorporation of additional key pathological processes, such as chronic perilesional inflammation, neuroaxonal degeneration, and remyelination. This will distinguish MS phenotypes that may present as clinically identical but are driven by different combinations of pathological processes. A more precise description of MS phenotypes will improve prognostication and personalized care as well as clinical trial design. Thus, our proposal provides an expanded framework for conceptualizing MS and for guiding development of biomarkers for monitoring activity along the main pathological axes in MS.


Assuntos
Esclerose Múltipla Crônica Progressiva , Esclerose Múltipla , Doenças do Sistema Nervoso , Biomarcadores , Progressão da Doença , Humanos , Inflamação , Esclerose Múltipla/diagnóstico , Esclerose Múltipla Crônica Progressiva/diagnóstico , Esclerose Múltipla Crônica Progressiva/patologia
19.
Bioeng Transl Med ; 6(3): e10231, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34589603

RESUMO

Tau is a microtubule binding protein which plays an important role in physiological functions but it is also involved in the pathogenesis of Alzheimer's disease and related tauopathies. While insoluble and ß-sheet containing tau neurofibrillary tangles have been the histopathological hallmark of these diseases, recent studies suggest that soluble tau oligomers, which are formed prior to fibrils, are the primary toxic species. Substantial efforts have been made to generate tau oligomers using purified recombinant protein strategies to study oligomer conformations as well as their toxicity. However, no specific toxic tau species has been identified to date, potentially due to the lack of cellular environment. Hence, there is a need for cell-based models for direct monitoring of tau oligomerization and aggregation. This review will summarize the recent advances in the cellular biosensor technology, with a focus on fluorescence resonance energy transfer, bimolecular fluorescence complementation, and split luciferase complementation approaches, to monitor formation of tau oligomers and aggregates in living cells. We will discuss the applications of the cellular biosensors in examining the heterogeneous tau conformational ensembles and factors affecting tau self-assembly, as well as detecting cell-to-cell propagation of tau pathology. We will also compare the advantages and limitations of each type of tau biosensors, and highlight their translational applications in biomarker development and therapeutic discovery.

20.
Artigo em Inglês | MEDLINE | ID: mdl-34639840

RESUMO

The news media, specifically online newspapers, is one of the powerful transmitters of discourse due to its rapid accessibility that contributes to social beliefs and attitudes that often shape our perceptions on dementia and Alzheimer's disease. The media portrayal of dementia is largely heterogeneous, but there is certainly an association between the influence of online news coverage and the social perceptions of dementia that need to be understood more broadly. In this study, we examined the portrayal of dementia in two online newspapers (The New York Times and The Guardian) that might have an influence on dementia discourse by comparing the content and form of the news coverage on dementia across time. This study was guided by three interconnected theoretical understandings: cultivation theory, agenda-setting theory, and spiral of silence theory. A total of 291 published articles featuring dementia from 2014 to 2019 were included in this study and a content analysis of the articles provided insight into the dementia-related news coverage. Our results showed that both newspapers have a decreasing trend in publishing articles related to dementia over time. In addition, dementia-related (modifiable) risk factors as principal news content was significantly associated with the year of publication. Despite a weak association between story categories and newspapers, the majority of articles reported preventive measures as the main story category. Although both newspapers featured more articles with a less negative tone across time when reporting on dementia, derogative wording, as discourse, was commonly used to address the illness. We have provided some insight into understanding how online newspapers potentially affect subjective representations of dementia as well as perpetuate dementia discourse. Finally, we suggest that future study may benefit from establishing a linkage between the depiction of dementia in online newspapers and the contextualization of dementia within cultures.


Assuntos
Doença de Alzheimer , Meios de Comunicação de Massa , Humanos , New York
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