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1.
Anal Chem ; 94(17): 6473-6481, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35438972

RESUMO

Colorimetric glucose sensors using enzyme-coronated gold nanoparticles have been developed for high-throughput assays to monitor the blood glucose levels of diabetic patients. Although those sensors have shown sensitivity and wide linear detection ranges, they suffer from poor selectivity and stability in detecting blood glucose, which has limited their practical use. To address this limitation, herein, we functionalized glucose-oxidase-coronated gold nanoparticles with an erythrocyte membrane (EM-GOx-GNPs). Because the erythrocyte membrane (EM) selectively facilitates the permeation of glucose via glucose transporter-1 (GLUT1), the functionalization of GOx-GNPs with EM improved the stability, selectivity (3.3- to 15.8-fold higher), and limit of detection (LOD). Both membrane proteins, GLUT1 and aquaporin-1 (AQP1), on EM were shown to be key components for selective glucose detection by treatment with their inhibitors. Moreover, we demonstrated the stability of EM-GOx-GNPs in high-antioxidant-concentration conditions, under long-term storage (∼4 weeks) and a freeze-thaw cycle. Selectivity of the EM-GOx-GNPs against other saccharides was increased, which improved the LOD in phosphate-buffered saline and human serum. Our results indicated that the functionalization of colorimetric glucose sensors with EM is beneficial for improving selectivity and stability, which may make them candidates for use in a practical glucose sensor.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Técnicas Biossensoriais/métodos , Glicemia , Membrana Eritrocítica , Glucose , Glucose Oxidase/metabolismo , Transportador de Glucose Tipo 1 , Ouro/metabolismo , Humanos
2.
Acc Chem Res ; 54(19): 3643-3655, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34516092

RESUMO

Reliable, inexpensive, and rapid diagnostic tools are essential to control and prevent the spread of infectious diseases. Many commercial kits for coronavirus disease 2019 (COVID-19) diagnostics have played a crucial role in the fight against the COVID-19 pandemic. Most current standard in vitro diagnostic (IVD) protocols for infectious diseases are sensitive but time-consuming and require sophisticated laboratory equipment and specially trained personnel. Recent advances in biosensor technology suggest the potential to deliver point-of-care (POC) diagnostics that are affordable and provide accurate results in a short time. The ideal "sample-in-answer-out" type fully integrated POC infection diagnostic platforms are expected to be autonomous or easy-to-operate, equipment-free or infrastructure-independent, and high-throughput or easy to upscale. In this Account, we detail the recent progress made by our group and others in the development of centrifugal microfluidic devices or lab-on-a-disc (LOAD) systems. Unlike conventional pump-based fluid actuation, the centrifugal force generated by spinning the disc induces liquid pumping and no external fluidic interconnects are required. This allows a total fluidic network required for multiple steps of biological assays to be integrated on a disc, enabling fully automated POC diagnostics. Various applications have been demonstrated, including liquid biopsy for personalized cancer management, food applications, and environmental monitoring; here, we focus on IVD for infectious disease. First, we introduce various on-disc unit operation technologies, including reagent storage, sedimentation, filtration, valving, decanting, aliquoting, mixing, separation, serial dilution, washing, and calibration. Such centrifugal microfluidic technologies have already proved promising for micro-total-analysis systems for automated IVD ranging from molecular detection of pathogens to multiplexed enzyme-linked immunosorbent assays (ELISAs) that use raw samples such as whole blood or saliva. Some recent examples of LOAD systems for molecular diagnostics in which some or all steps of the assays are integrated on a disc, including pathogen enrichment, nucleic acid extraction, amplification, and detection, are discussed in detail. We then introduce fully automated ELISA systems with enhanced sensitivity. Furthermore, we demonstrate a toy-inspired fidget spinner that enables electricity-free and rapid analysis of pathogens from undiluted urine samples of patients with urinary tract infection symptoms and a phenotypic antimicrobial susceptibility test for an extreme POC diagnostics application. Considering the urgent need for cost-effective and reliable POC infection diagnostic tools, especially in the current pandemic crisis, the current limitations and future directions of fast and broad adaptation in real-world settings are also discussed. With proper attention to key challenges and leverage with recent advances in bio-sensing technologies, molecular biology, nanomaterials, analytical chemistry, miniaturization, system integration, and data management, LOAD systems hold the potential to deliver POC infection diagnostic tools with unprecedented performance regarding time, accuracy, and cost. We hope the new insight and promise of LOAD systems for POC infection diagnostics presented in this Account can spark new ideas and inspire further research and development to create better healthcare systems for current and future pandemics.


Assuntos
Teste para COVID-19/métodos , COVID-19/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito , Técnicas Biossensoriais/métodos , COVID-19/virologia , Teste para COVID-19/instrumentação , Centrifugação , Humanos , Dispositivos Lab-On-A-Chip , RNA Viral/análise , RNA Viral/isolamento & purificação , RNA Viral/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação
3.
Int J Mol Sci ; 23(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36077321

RESUMO

Activation of microglial cells by intrinsic or extrinsic insult causes neuroinflammation, a common phenomenon in neurodegenerative diseases. Prevention of neuroinflammation may ameliorate many neurodegenerative disease progressions. Dioscorea nipponica Makino (DN) extract can alleviate muscular atrophy and inflammatory diseases; however, the efficacy and mechanism of action in microglial cells remain unknown. The current study investigates the possible anti-inflammatory effects and mechanisms of Dioscorea nipponica Makino ethanol extract and its steroidal saponin dioscin. Our in vitro study shows that Dioscorea nipponica rhizome ethanol extract (DNRE) and dioscin protect against lipopolysaccharide (LPS)-activated inflammatory responses in BV-2 microglial cells by inhibiting phosphorylation and the nuclear translocation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), resulting in the downregulation of pro-inflammatory cytokines and enzymes. Consistent with our previous report of dioscin-mediated enhancement of neurotrophic factors in dopaminergic cells, here we found that dioscin upregulates brain-derived neurotrophic factor (BDNF) and cAMP-response element binding protein (CREB) phosphorylation (pCREB) in the cerebral cortex and hippocampus regions of the mouse brain. Scopolamine treatment increased pro-inflammatory enzyme levels and reduced the expression of BDNF and pCREB in the hippocampus and cortex regions, which led to impaired learning and referencing memory in mice. Pre-treatment of dioscin for 7 days substantially enhanced mice performances in maze studies, indicating amelioration in cognitive deficits. In conclusion, DNRE and its active compound dioscin protect against neurotoxicity most likely by suppressing NF-κB phosphorylation and upregulating neurotrophic factor BDNF.


Assuntos
Dioscorea , Doenças Neurodegenerativas , Animais , Fator Neurotrófico Derivado do Encéfalo , Diosgenina/análogos & derivados , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico , Camundongos , NF-kappa B , Doenças Neuroinflamatórias , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Escopolamina/efeitos adversos
4.
Molecules ; 27(9)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35566180

RESUMO

Autophagy is a cellular homeostatic process by which cells degrade and recycle their malfunctioned contents, and impairment in this process could lead to Parkinson's disease (PD) pathogenesis. Dioscin, a steroidal saponin, has induced autophagy in several cell lines and animal models. The role of dioscin-mediated autophagy in PD remains to be investigated. Therefore, this study aims to investigate the hypothesis that dioscin-regulated autophagy and autophagy-related (ATG) proteins could protect neuronal cells in PD via reducing apoptosis and enhancing neurogenesis. In this study, the 1-methyl-4-phenylpyridinium ion (MPP+) was used to induce neurotoxicity and impair autophagic flux in a human neuroblastoma cell line (SH-SY5Y). The result showed that dioscin pre-treatment counters MPP+-mediated autophagic flux impairment and alleviates MPP+-induced apoptosis by downregulating activated caspase-3 and BCL2 associated X, apoptosis regulator (Bax) expression while increasing B-cell lymphoma 2 (Bcl-2) expression. In addition, dioscin pre-treatment was found to increase neurotrophic factors and tyrosine hydroxylase expression, suggesting that dioscin could ameliorate MPP+-induced degeneration in dopaminergic neurons and benefit the PD model. To conclude, we showed dioscin's neuroprotective activity in neuronal SH-SY5Y cells might be partly related to its autophagy induction and suppression of the mitochondrial apoptosis pathway.


Assuntos
1-Metil-4-fenilpiridínio , Doença de Parkinson , 1-Metil-4-fenilpiridínio/toxicidade , Animais , Apoptose , Autofagia , Linhagem Celular Tumoral , Diosgenina/análogos & derivados , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/etiologia , Doença de Parkinson/metabolismo
5.
Medicina (Kaunas) ; 58(9)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36143952

RESUMO

BACKGROUND AND OBJECTIVES: Endobronchial ultrasound transbronchial lung biopsy with guide sheath (EBUS-GS-TBLB) has been regarded as a reasonable diagnostic method with an acceptable diagnostic yield. In addition, EBUS-GS-TBLB is considered safer and less invasive compared to percutaneous needle biopsy and thoracoscopic surgery. However, we encountered a case of life-threatening procedure-related fatal infection, which was successfully managed. CASE PRESENTATION: A 61-year-old man with a 30 pack-year smoking history was referred to our clinic with a necrotic lung mass in the right middle lobe on a chest computed tomography scan. EBUS-GS-TBLB was performed for a pathological diagnosis without immediate complications. Eight days after the procedure, the patient visited the hospital with sudden hemoptysis and severe dyspnea with fever. A chest computed tomography revealed a ruptured lung abscess and pneumonia, developed after EBUS-GS-TBLB. Extracorporeal membrane oxygenation (ECMO) and mechanical ventilation were initiated to manage refractory hypoxia. While maintaining ECMO, video-assisted thoracoscopic surgery was performed at the patient's bedside in the intensive care unit. After surgery, the patient's vital signs gradually improved, and a chest computed tomography revealed a reduction in the extent of the lung abscess. RESULTS: Although EBUS-GS-TBLB is minimally invasive and relatively safe when used for the diagnosis of peripheral lung lesions, pulmonary physicians should be aware of this rare but critical complication. CONCLUSIONS: We suggest that the careful prescription of prophylactic antibiotics before EBUS-GS-TBLB would be wise if the mass featured a necrotic, cavitary, or cystic lesion.


Assuntos
Abscesso Pulmonar , Neoplasias Pulmonares , Antibacterianos , Biópsia/métodos , Broncoscopia/métodos , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Abscesso Pulmonar/patologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade
6.
Medicina (Kaunas) ; 58(11)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36363483

RESUMO

Background: Acute eosinophilic pneumonia (AEP) is a rare acute respiratory disease accompanied by fever, shortness of breath, and cough. Although the pathogenesis of the disease is not yet established, the patient's condition improves with a rapid therapeutic response to systemic corticosteroids. Conventional cigarettes or heat-not-burn cigarettes are the most common cause of AEP among young people. Case Presentation: A 22-year-old woman with dyspnea, cough, and fever did not improve after visiting the local medical center and was admitted to the emergency room. The patient denied having any recent travel history or insect bites. She was treated with appropriate antibiotics according to the community acquired pneumonia, but there was no improvement. Chest radiography showed bilateral patches of pulmonary infiltration, and chest computed tomography revealed bilateral multifocal patchy consolidations with multiple small nodular ground-glass opacities and interlobular septal thickening. The bronchoalveolar lavage result was dominantly eosinophilic. The patient's condition improved rapidly after the use of intravenous methylprednisolone and then a change to oral methylprednisolone. Finally, the patient was hospitalized for 9 days, and the duration of use of methylprednisolone including outpatient visits was 14 days. Results: The early treatment of AEP yields a good prognosis, but since the symptoms of AEP are similar to those of infectious diseases such as community-acquired pneumonia, physicians should be meticulous in differentiating AEP from other diseases. Conclusions: Since AEP shows a good response to steroids, early detection using an appropriate diagnostic method is recommended. In addition, there should be strong education against smoking in any form.


Assuntos
Queimaduras , Eosinofilia Pulmonar , Produtos do Tabaco , Feminino , Humanos , Adolescente , Adulto Jovem , Adulto , Eosinofilia Pulmonar/diagnóstico , Eosinofilia Pulmonar/tratamento farmacológico , Eosinofilia Pulmonar/etiologia , Tosse , Temperatura Alta , Metilprednisolona/uso terapêutico , Doença Aguda
7.
Clin Sci (Lond) ; 135(1): 231-257, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33443284

RESUMO

General control non-depressible 5 (GCN5) or lysine acetyltransferase 2A (KAT2A) is one of the most highly studied histone acetyltransferases. It acts as both histone acetyltransferase (HAT) and lysine acetyltransferase (KAT). As an HAT it plays a pivotal role in the epigenetic landscape and chromatin modification. Besides, GCN5 regulates a wide range of biological events such as gene regulation, cellular proliferation, metabolism and inflammation. Imbalance in the GCN5 activity has been reported in many disorders such as cancer, metabolic disorders, autoimmune disorders and neurological disorders. Therefore, unravelling the role of GCN5 in different diseases progression is a prerequisite for both understanding and developing novel therapeutic agents of these diseases. In this review, we have discussed the structural features, the biological function of GCN5 and the mechanical link with the diseases associated with its imbalance. Moreover, the present GCN5 modulators and their limitations will be presented in a medicinal chemistry perspective.


Assuntos
Montagem e Desmontagem da Cromatina , Epigênese Genética , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Acetilação , Animais , Antineoplásicos/farmacologia , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Epigênese Genética/efeitos dos fármacos , Histona Acetiltransferases/antagonistas & inibidores , Histona Acetiltransferases/química , Histona Acetiltransferases/genética , Humanos , Lisina , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Neoplasias/patologia , Domínios Proteicos , Processamento de Proteína Pós-Traducional , Relação Estrutura-Atividade , Especificidade por Substrato
8.
Int J Mol Sci ; 22(9)2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33925146

RESUMO

The proton-activated G protein-coupled receptor (GPCR) 4 (GPR4) is constitutively active at physiological pH, and GPR4 knockout protected dopaminergic neurons from caspase-dependent mitochondria-associated apoptosis. This study explored the role of GPR4 in a 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-treated mouse model of Parkinson's disease (PD). In mice, subchronic MPTP administration causes oxidative stress-induced apoptosis in the dopaminergic neurons of the substantia nigra pars compacta (SNpc), resulting in motor deficits. NE52-QQ57, a selective GPR4 antagonist, reduced dopaminergic neuronal loss in MPTP-treated mice, improving motor and memory functions. MPTP and NE52-QQ57 co-treatment in mice significantly decreased pro-apoptotic marker Bax protein levels and increased anti-apoptotic marker Bcl-2 protein levels in the SNpc and striatum. MPTP-induced caspase 3 activation and poly (ADP-ribose) polymerase (PARP) cleavage significantly decreased in the SNpc and striatum of mice co-treated with NE52-QQ57. MPTP and NE52-QQ57 co-treatment significantly increased tyrosine hydroxylase (TH)-positive cell numbers in the SNpc and striatum compared with MPTP alone. NE52-QQ57 and MPTP co-treatment improved rotarod and pole test-assessed motor performance and improved Y-maze test-assessed spatial memory. Our findings suggest GPR4 may represent a potential therapeutic target for PD, and GPR4 activation is involved in caspase-mediated neuronal apoptosis in the SNpc and striatum of MPTP-treated mice.


Assuntos
Doença de Parkinson/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/efeitos adversos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Animais , Apoptose/genética , Encéfalo/metabolismo , Caspase 3/metabolismo , Caspases/metabolismo , Corpo Estriado/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/metabolismo , Doença de Parkinson/fisiopatologia , Parte Compacta da Substância Negra/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/genética , Substância Negra/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
9.
Molecules ; 26(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34066108

RESUMO

Lindera obtusiloba Blume (family, Lauraceae), native to Northeast Asia, has been used traditionally in the treatment of trauma and neuralgia. In this study, we investigated the neuroinflammatory effect of methanol extract of L. obtusiloba stem (LOS-ME) in a scopolamine-induced amnesia model and lipopolysaccharide (LPS)-stimulated BV2 microglia cells. LOS-ME downregulated the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, inflammatory cytokines, and inhibited the phosphorylation of nuclear factor kappa-B (NF-ĸB) and extracellular signal-regulated kinase (ERK) in LPS-stimulated BV2 cells. Male C57/BL6 mice were orally administered 20 and 200 mg/kg of LOS-ME for one week, and 2 mg/kg of scopolamine was administered intraperitoneally on the 8th day. In vivo behavioral experiments (Y-maze and Morris water maze test) confirmed that LOS-ME alleviated cognitive impairments induced by scopolamine and the amount of iNOS expression decreased in the hippocampus of the mouse brain. Microglial hyper-activation was also reduced by LOS-ME pretreatment. These findings suggest that LOS-ME might have potential in the treatment for cognitive improvement by regulating neuroinflammation.


Assuntos
Amnésia/induzido quimicamente , Amnésia/tratamento farmacológico , Anti-Inflamatórios/administração & dosagem , Lindera/química , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Fitoterapia/métodos , Extratos Vegetais/administração & dosagem , Escopolamina/efeitos adversos , Animais , Células Cultivadas , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Hipocampo/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II/metabolismo , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento
10.
Mov Disord ; 35(1): 20-33, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31680318

RESUMO

Excessive activation of microglia and subsequent release of proinflammatory cytokines play a crucial role in neuroinflammation and neurodegeneration in Parkinson's disease (PD). Components of the nucleotide-binding oligomerization domain and leucine-rich-repeat- and pyrin-domain-containing 3 inflammasome complex, leucine-rich-repeat- and pyrin-domain-containing 3, caspase-1, and apoptosis-associated speck-like protein containing a CARD, are highly expressed in activated microglia in PD patient brains. Findings suggest that neurotoxins, aggregation of α-synuclein, mitochondrial reactive oxygen species, and disrupted mitophagy are the key regulators of microglial leucine-rich-repeat- and pyrin-domain-containing 3 inflammasome activation and release of interleukin-1ß and interleukin-18 caspase-1-mediated pyroptotic cell death in the substantia nigra of the brain. Although this evidence suggests the leucine-rich-repeat- and pyrin-domain-containing 3 inflammasome may be a potential drug target for treatment of PD, the exact mechanism of how the microglia sense these stimuli and initiate leucine-rich-repeat- and pyrin-domain-containing 3 inflammasome signaling is unknown. Here, the molecular mechanism and regulation of microglial leucine-rich-repeat- and pyrin-domain-containing 3 inflammasome activation and its role in the pathogenesis of PD are discussed. Moreover, the potential of both endogenous and synthetic leucine-rich-repeat- and pyrin-domain-containing 3 inflammasome modulators, long noncoding RNA, microRNA to develop novel therapeutics to treat PD is presented. Overall, we recommend that the microglial leucine-rich-repeat- and pyrin-domain-containing 3 inflammasome can be a potential target for PD treatment. © 2019 International Parkinson and Movement Disorder Society.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Microglia/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Doença de Parkinson/metabolismo , Transtornos Parkinsonianos/metabolismo , Animais , Encéfalo/metabolismo , Humanos
11.
Analyst ; 145(6): 2125-2132, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-31971165

RESUMO

In the development of enzymatic glucose sensors, accurate glucose sensing has been a challenging task because of the existence of numerous interfering molecules in the blood. Meanwhile, red blood cells (RBCs) selectively uptake glucose via a membrane protein called glucose transporter-1. In this study, we developed the RBC membrane (RBCM)-coated enzymatic glucose sensors that mimic the glucose uptake. The RBCM-coated sensors were examined via scanning electron microscopy, atomic force microscopy, and ATR-FTIR. We optimized the glucose permeability of the RBCM filter by controlling the thickness of the filter. The sensing range of the optimized sensor was 1-15 mM, the detection limit was 0.66 mM, and the sensitivity was 2.978 µA mM-1. Intriguingly, the RBCM-coated sensor was highly accurate and precise, despite the coexistence of glucose and interfering molecules (e.g., mannose, galactose, ascorbic acid, uric acid, and cysteine). For each interfering molecule, the errors of our sensor were 0.8 to 2.3%, which was 4.8-14.2 times more accurate than the uncoated one. A similar result was verified for a human serum sample containing countless interfering molecules. Also, the sensing performance of the sensor was consistent after 4 weeks of storage. The results suggest that applying RBCM may improve the selectivity of various types of glucose sensors including the continuous monitoring system.


Assuntos
Glicemia/análise , Técnicas Eletroquímicas/métodos , Membrana Eritrocítica/química , Eritrócitos/química , Glucose 1-Desidrogenase/química , Glicemia/química , Técnicas Eletroquímicas/instrumentação , Eletrodos , Enzimas Imobilizadas/química , Transportador de Glucose Tipo 1/química , Humanos , Oxirredução
12.
Int J Mol Sci ; 21(20)2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33053856

RESUMO

In Parkinson's disease, mitochondrial oxidative stress-mediated apoptosis is a major cause of dopaminergic neuronal loss in the substantia nigra (SN). G protein-coupled receptor 4 (GPR4), previously recognised as an orphan G protein coupled-receptor (GPCR), has recently been claimed as a member of the group of proton-activated GPCRs. Its activity in neuronal apoptosis, however, remains undefined. In this study, we investigated the role of GPR4 in the 1-methyl-4-phenylpyridinium ion (MPP+) and hydrogen peroxide (H2O2)-treated apoptotic cell death of stably GPR4-overexpressing and stably GPR4-knockout human neuroblastoma SH-SY5Y cells. In GPR4-OE cells, MPP+ and H2O2 were found to significantly increase the expression levels of both mRNA and proteins of the pro-apoptotic Bcl-2-associated X protein (Bax) genes, while they decreased the anti-apoptotic B-cell lymphoma 2 (Bcl-2) genes. In addition, MPP+ treatment activated Caspase-3, leading to the cleavage of poly (ADP-ribose) polymerase (PARP) and decreasing the mitochondrial membrane potential (ΔΨm) in GPR4-OE cells. In contrast, H2O2 treatment significantly increased the intracellular calcium ions (Ca2+) and reactive oxygen species (ROS) in GPR4-OE cells. Further, chemical inhibition by NE52-QQ57, a selective antagonist of GPR4, and knockout of GPR4 by clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 decreased the Bax/Bcl-2 ratio and ROS generation, and stabilised the ΔΨm, thus protecting the SH-SY5Y cells from MPP+- or H2O2-induced apoptotic cell death. Moreover, the knockout of GPR4 decreased the proteolytic degradation of phosphatidylinositol biphosphate (PIP2) and subsequent release of the endoplasmic reticulum (ER)-stored Ca2+ in the cytosol. Our results suggest that the pharmacological inhibition or genetic deletion of GPR4 improves the neurotoxin-induced caspase-dependent mitochondrial apoptotic pathway, possibly through the modulation of PIP2 degradation-mediated calcium signalling. Therefore, GPR4 presents a potential therapeutic target for neurodegenerative disorders such as Parkinson's disease.


Assuntos
Caspases/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Mitofagia , Neurotoxinas/farmacologia , Receptores Acoplados a Proteínas G/deficiência , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Morte Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteólise , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
13.
Int J Mol Sci ; 21(21)2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33147699

RESUMO

Microglia-mediated neuroinflammation is one of the key mechanisms involved in acute brain injury and chronic neurodegeneration. This study investigated the inhibitory effects of 2-hydroxy-4-methylbenzoic anhydride (HMA), a novel synthetic derivative of HTB (3-hydroxy-4-trifluoromethylbenzoic acid) on neuroinflammation and underlying mechanisms in activated microglia in vitro and an in vivo mouse model of Parkinson's disease (PD). In vitro studies revealed that HMA significantly inhibited lipopolysaccharide (LPS)-stimulated excessive release of nitric oxide (NO) in a concentration dependent manner. In addition, HMA significantly suppressed both inducible NO synthase and cyclooxygenase-2 (COX-2) at the mRNA and protein levels in LPS-stimulated BV-2 microglia cells. Moreover, HMA significantly inhibited the proinflammatory cytokines such as interleukin (IL)-1beta, IL-6, and tumor necrosis factor-alpha in LPS-stimulated BV-2 microglial cells. Furthermore, mechanistic studies ensured that the potent anti-neuroinflammatory effects of HMA (0.1, 1.0, and 10 µM) were mediated by phosphorylation of nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) in LPS-stimulated BV-2 cells. In vivo evaluations revealed that intraperitoneal administration of potent neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 20 mg/kg, four times a 1 day) in mice resulted in activation of microglia in the brain in association with severe behavioral deficits as assessed using a pole test. However, prevention of microglial activation and attenuation of Parkinson's disease (PD)-like behavioral changes was obtained by oral administration of HMA (30 mg/kg) for 14 days. Considering the overall results, our study showed that HMA exhibited strong anti-neuroinflammatory effects at lower concentrations than its parent compound. Further work is warranted in other animal and genetic models of PD for evaluating the efficacy of HMA to develop a potential therapeutic agent in the treatment of microglia-mediated neuroinflammatory disorders, including PD.


Assuntos
Benzoatos/farmacologia , Ciclo-Oxigenase 2/metabolismo , Inflamação/tratamento farmacológico , Neurônios/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Administração Oral , Animais , Sobrevivência Celular , Modelos Animais de Doenças , Desenho de Fármacos , Técnicas In Vitro , Lipopolissacarídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Modelos Teóricos , Neuroglia/metabolismo , Óxido Nítrico/metabolismo , Peptídeos/química , Fosforilação , Salicilatos/química , Transdução de Sinais
14.
Respir Res ; 20(1): 142, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286968

RESUMO

BACKGROUND: Virtual bronchoscopy navigation (VBN) is widely used for assistance in the histological examination of lung nodules. However, little is known about the optimal CT radiation dose for VBN. Therefore, we performed an animal study to evaluate the feasibility of low dose CT (LDCT) for VBN. METHODS: Ten pigs underwent standard dose CT (as a reference) and four different LDCT protocols: LDCT 1, 120 kVp, 15 mAs; LDCT 2, 120 kVp, 8 mAs; LDCT 3, 100 kVp, 7 mAs; and LDCT 4, 100 kVp, 4 mAs. As targets for the VBN, 10 mm virtual lesions were created in the central and peripheral bronchi. To assess the performance of the VBN, the navigation direction (direction of reconstructed pathways to the target) and the number of branching's (the number of peripheral bronchi to the target) were evaluated. RESULTS: The mean effective doses significantly differed across the four LDCTs (P <  0.001). For both central and peripheral virtual targets, there were significant differences in the accuracy of the navigation direction and the number of branching's of the VBNs across the four LDCTs (P <  0.001 for all). Regarding the accuracy of the navigation direction and the number of branching's, the areas under the curves of the ROCs were 0.9352 and 0.9324, respectively, for central virtual targets, and 0.8696 and 0.8783, respectively, for peripheral virtual targets. Youden's index indicated that the optimal effective CT scan dose for both central and peripheral virtual targets was 0.238 mSv. CONCLUSIONS: LDCT is feasible for VBN.


Assuntos
Broncoscopia/métodos , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Animais , Estudos de Viabilidade , Feminino , Suínos
15.
Nanotechnology ; 30(8): 085501, 2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30524017

RESUMO

With the rapid development of nanotechnology and its associated waste stream, public concern is growing over the potential toxicity exposure to heavy metal ions poses to the human body and the environment. Herein, we report an extremely sensitive Kelvin probe force microscopy (KPFM)-based platform for detecting nanotoxic materials (e.g. Ag+) accomplished by probing the integrated surface potential differences of a single gold nanoparticle on which an interaction between probe DNA and target DNA occurs. This interaction can amplify the surface potential of the nanoparticle owing to the coordination bond mediated by Ag+ (cytosine-Ag+-cytosine base pairs). Interestingly, compared with conventional methods, this platform is capable of extremely sensitive Ag+ detection (∼1 fM) in a remarkably wide-range (1 fM to 1 µM). Furthermore, this platform enables Ag+ detection in a practical sample (general drinking water), and this KPFM-based technique may have the potential to detect other toxic heavy metal ions and single nucleotide polymorphisms by designing specific DNA sequences.


Assuntos
DNA/química , Água Potável/análise , Ouro/química , Nanopartículas Metálicas/química , Prata/análise , Poluentes Químicos da Água/análise , Sondas de DNA/química , Limite de Detecção , Microscopia de Força Atômica/métodos
16.
BMC Pulm Med ; 19(1): 151, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31474222

RESUMO

BACKGROUND: Myelolipoma is a rare benign tumor composed of mature adipose and hematopoietic tissues. Most myelolipomas are found in the adrenal glands, whereas intrathoracic myelolipoma is extremely rare. In particular, bronchial myelolipoma without the involvement of lung parenchyma has never been reported. CASE PRESENTATION: A previously healthy 38-year-old male developed dyspnea and a productive cough. Computed tomography revealed an endobronchial mass at the right bronchus intermedius and subsequent atelectasis of the right middle and lower lobes. Flexible bronchoscopy found a total obstruction of the right bronchus intermedius due to an endobronchial tumor. Using a rigid bronchoscope, the endobronchial tumor was resected and the base of the tumor was additionally ablated with a diode laser to prevent recurrence. The removed endobronchial tumor was a 13 mm × 20 mm-sized oval-shaped mass and was pathologically diagnosed as bronchial myelolipoma. Chest radiographs, obtained on the day following the procedure, showed an improvement of atelectasis, and accompanying symptoms were immediately improved. Follow-up bronchoscopy performed after 12 months evidenced no recurrence of the bronchial myelolipoma. CONCLUSIONS: We used bronchoscopic intervention in patients with solitary bronchial myelolipoma and there was no evidence of recurrence.


Assuntos
Neoplasias Brônquicas/patologia , Neoplasias Brônquicas/cirurgia , Mielolipoma/patologia , Mielolipoma/cirurgia , Adulto , Broncoscopia , Humanos , Terapia a Laser/métodos , Masculino , Tomografia Computadorizada por Raios X
17.
Nanotechnology ; 29(34): 345604, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-29848798

RESUMO

Amyloid aggregates have emerged as a significant hallmark of neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. Although it has been recently reported that microwave heating induces amyloid aggregation compared with conventional heating methods, the mechanism of amyloid aggregate induction has remained unclear. In this study, we investigated the formation of oligomeric amyloid aggregates (OAAs) by microwave irradiation at microscale volumes of solution. Microwave irradiation of protein monomer solution triggered rapid formation of OAAs within 7 min. We characterized the formation of OAAs using atomic force microscopy, thioflavin T fluorescent assay and circular dichroism. In the microwave system, we also investigated the inhibitory effect on the formation of amyloid aggregates by L-ascorbic acid as well as enhanced amyloid aggregation by silver nanomaterials such as nanoparticles and nanowires. We believe that microwave technology has the potential to facilitate the study of amyloid aggregation in the presence of chemical agents or nanomaterials.


Assuntos
Amiloide/química , Micro-Ondas , Agregados Proteicos , Dicroísmo Circular , Lactoglobulinas/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Prata/química
18.
BMC Pulm Med ; 18(1): 137, 2018 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-30103727

RESUMO

BACKGROUND: The diagnostic yields and safety profiles of transbronchial lung biopsy have not been evaluated in inexperienced physicians using the combined modality of radial probe endobronchial ultrasound and a guide sheath (EBUS-GS). This study assessed the utility and safety of EBUS-GS during the learning phase by referring to a database of performed EBUS-GS procedures. METHODS: From December 2015 to January 2017, all of the consecutive patients who underwent EBUS-GS were registered. During the study period, two physicians with no previous experience performed the procedure. To assess the diagnostic yields, learning curve, and safety profile of EBUS-GS performed by these inexperienced physicians, the first 100 consecutive EBUS-GS procedures were included in the evaluation. RESULTS: The overall diagnostic yield of EBUS-GS performed by two physicans in 200 patients with a peripheral lung lesion was 73.0%. Learning curve analyses showed that the diagnostic yields were stable, even when the procedure was performed by beginners. Complications related to EBUS-GS occurred in three patients (1.5%): pneumothorax developed in two patients (1%) and resolved spontaneously without chest tube drainage; another patient (0.5%) developed a pulmonary infection after EBUS-GS. There were no cases of pneumothorax requiring chest tube drainage, severe hemorrhage, respiratory failure, premature termination of the procedure, or procedure-related mortality. CONCLUSIONS: EBUS-GS is a safe and stable procedure with an acceptable diagnostic yield, even when performed by physicians with no previous experience.


Assuntos
Broncoscopia/métodos , Biópsia Guiada por Imagem/instrumentação , Neoplasias Pulmonares/patologia , Pulmão/patologia , Ultrassonografia de Intervenção/métodos , Idoso , Brônquios/diagnóstico por imagem , Brônquios/patologia , Broncoscopia/efeitos adversos , Competência Clínica , Feminino , Humanos , Biópsia Guiada por Imagem/métodos , Curva de Aprendizado , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Pneumotórax/etiologia , República da Coreia , Infecções Respiratórias/etiologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Ultrassonografia de Intervenção/instrumentação
19.
Int J Mol Sci ; 19(11)2018 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-30384504

RESUMO

Bisphenol A (BPA) is synthetic organic compound that exhibits estrogen-like properties and it induces mitochondrial superoxide production. Melatonin (Mela) protects against BPA-mediated cell damage and apoptosis. However, the antioxidative effects of Mela against BPA-induced superoxide production in porcine oocytes are still not known. In this study, we investigated the antioxidative effects of Mela against BPA-derived superoxide on oocyte maturation in pigs. To investigate the effects of the superoxide specific scavenger, Mito-TEMPO, on porcine oocyte maturation in response to BPA exposure apoptosis proteins, we treated the oocytes with Mito-TEMPO (0.1 µM) after pre-treating them with BPA (75 µM) for 22 h. As expected, the reduction in meiotic maturation and cumulus cell expansion of cumulus-oocyte-complexes (COCs) in the BPA (75 µM) treated group was recovered (p < 0.01) by treatment with Mito-TEMPO (0.1 µM). An increase in the levels of mitochondrial apoptotic proteins (AIF, cleaved Cas 3 and cleaved Parp1) in response to BPA-induced damage was also reduced by Mito-TEMPO treatment in porcine COCs. Interestingly, we confirmed the positive effects of Mela with respect to superoxide production upon BPA exposure during oocyte maturation and also confirmed the reduction in mitochondrial apoptosis in Mela (0.1 µM)-treated porcine COCs. These results provide evidence for the first time that antioxidative effects of Mela on BPA-derived superoxide improve porcine oocyte maturation.


Assuntos
Antioxidantes/farmacologia , Compostos Benzidrílicos/farmacologia , Melatonina/farmacologia , Mitocôndrias/metabolismo , Oócitos/metabolismo , Fenóis/farmacologia , Superóxidos/metabolismo , Animais , Feminino , Proteínas Mitocondriais/metabolismo , Suínos
20.
Can J Infect Dis Med Microbiol ; 2018: 1698241, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30224940

RESUMO

PURPOSE: The aim of this pre- and postintervention cohort study was evaluating how effectively rapid pathogen identification with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) detected the causative organisms in sepsis. METHODS: All consecutive adult patients who had bacteremia within 72 h of intensive care unit admission and met ≥2 quick Sequential Organ Failure Assessment criteria at intensive care unit admission were analyzed. The patients whose microorganisms were identified via MALDI-TOF MS between March 2014 and February 2016 formed the postintervention group. The patients whose microorganisms were identified by using conventional methods between March 2011 and February 2013 formed the preintervention group. RESULTS: The postintervention group (n=58) had a shorter mean time from blood draw to receiving the antimicrobial susceptibility results than the preintervention group (n=40) (90.2 ± 32.1 vs. 108.7 ± 43.1 h; p=0.02). The postintervention group was also more likely to have received active antimicrobial therapy by the time the susceptibility report became available (77% vs. 47%; p=0.005). Its 28-day mortality was also lower (40% vs. 70%; p=0.003). Univariate analysis showed that identification via MALDI-TOF MS (odds ratio, 0.28; 95% confidence interval, 0.12-0.66; p=0.004) and active therapy (odds ratio, 0.38; 95% confidence interval, 0.16-0.95; p=0.04) were associated with lower 28-day mortality. CONCLUSION: Rapid microorganism identification via MALDI-TOF MS followed by appropriate antimicrobial therapy may improve the clinical outcomes of patients with sepsis.

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