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1.
Proc Natl Acad Sci U S A ; 119(28): e2202256119, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35867766

RESUMO

Phenotypic variations in the retinal pigment epithelial (RPE) layer are often a predecessor and driver of ocular degenerative diseases, such as age-related macular degeneration (AMD), the leading cause of vision loss in the elderly. We previously identified the orphan nuclear receptor-related 1 (NURR1), from a nuclear receptor atlas of human RPE cells, as a candidate transcription factor potentially involved in AMD development and progression. In the present study we characterized the expression of NURR1 as a function of age in RPE cells harvested from human donor eyes and in donor tissue from AMD patients. Mechanistically, we found an age-dependent shift in NURR1 dimerization from NURR1-RXRα heterodimers toward NURR1-NURR1 homodimers in primary human RPE cells. Additionally, overexpression and activation of NURR1 attenuated TNF-α-induced epithelial-to-mesenchymal transition (EMT) and migration, and modulated EMT-associated gene and protein expression in human RPE cells independent of age. In vivo, oral administration of IP7e, a potent NURR1 activator, ameliorated EMT in an experimental model of wet AMD and improved retinal function in a mouse model that presents with dry AMD features, impacting AMD phenotype, structure, and function of RPE cells, inhibiting accumulation of immune cells, and diminishing lipid accumulation. These results provide insight into the mechanisms of action of NURR1 in the aging eye, and demonstrate that the relative expression levels and activity of NURR1 is critical for both physiological and pathological functions of human RPE cells through RXRα-dependent regulation, and that targeting NURR1 may have therapeutic potential for AMD by modulating EMT, inflammation, and lipid homeostasis.


Assuntos
Transição Epitelial-Mesenquimal , Degeneração Macular , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares , Epitélio Pigmentado da Retina , Idoso , Animais , Humanos , Lipídeos , Degeneração Macular/metabolismo , Degeneração Macular/patologia , Camundongos , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/química , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Fenótipo , Multimerização Proteica , Epitélio Pigmentado da Retina/metabolismo
2.
Epilepsy Behav ; 150: 109570, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38070412

RESUMO

OBJECTIVE: Epidemiological studies have reported an association between epilepsy and dementia. However, the causal relationship between epilepsy and the risk of dementia is not clear. We aimed to inspect the causal effect of epilepsy on memory loss and dementia. METHODS: We analyzed summary data of epilepsy, memory loss, and dementia from the genome-wide association study (GWAS) using the two-sample Mendelian randomization (MR) method. We used the estimated odds ratio of memory loss and dementia associated with each of the genetically defined traits to infer evidence for a causal relationship with the following exposures: all epilepsy, focal epilepsy (including focal epilepsy with hippocampal sclerosis, lesion-negative focal epilepsy, and focal epilepsy with other lesions), and genetic generalized epilepsy (including childhood absence epilepsy, generalized tonic-clonic seizures alone, Juvenile absence epilepsy, and Juvenile myoclonic epilepsy). RESULTS: According to the result of MR using the inverse variance weighted method (IVW), we found that genetically predicted epilepsy did not causally increase the risk of memory loss and dementia (p > 0.05). Results of the MR-Egger and weighted median method were consistent with the IVW method. CONCLUSIONS: No evidence has been found to support the notion that epilepsy can result in memory loss and dementia. The associations observed in epidemiological studies could be attributed, in part, to confounding or nongenetic determinants.


Assuntos
Demência , Epilepsias Parciais , Epilepsia Tipo Ausência , Humanos , Criança , Análise da Randomização Mendeliana , Estudo de Associação Genômica Ampla , Epilepsia Tipo Ausência/complicações , Epilepsia Tipo Ausência/epidemiologia , Epilepsia Tipo Ausência/genética , Amnésia , Demência/complicações , Demência/epidemiologia , Demência/genética
3.
Int J Mol Sci ; 25(13)2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-39000525

RESUMO

Abiotic stress, especially drought stress, poses a significant threat to terrestrial plant growth, development, and productivity. Although mulberry has great genetic diversity and extensive stress-tolerant traits in agroforestry systems, only a few reports offer preliminary insight into the biochemical responses of mulberry leaves under drought conditions. In this study, we performed a comparative metabolomic and transcriptomic analysis on the "drooping mulberry" (Morus alba var. pendula Dippel) under PEG-6000-simulated drought stress. Our research revealed that drought stress significantly enhanced flavonoid accumulation and upregulated the expression of phenylpropanoid biosynthetic genes. Furthermore, the activities of superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) content were elevated. In vitro enzyme assays and fermentation tests indicated the involvement of flavonol synthase/flavanone 3-hydroxylase (XM_010098126.2) and anthocyanidin 3-O-glucosyltransferase 5 (XM_010101521.2) in the biosynthesis of flavonol aglycones and glycosides, respectively. The recombinant MaF3GT5 protein was found to recognize kaempferol, quercetin, and UDP-glucose as substrates but not 3-/7-O-glucosylated flavonols and UDP-rhamnose. MaF3GT5 is capable of forming 3-O- and 7-O-monoglucoside, but not di-O-glucosides, from kaempferol. This implies its role as a flavonol 3, 7-O-glucosyltransferase. The findings from this study provided insights into the biosynthesis of flavonoids and could have substantial implications for the future diversified utilization of mulberry.


Assuntos
Secas , Flavonoides , Regulação da Expressão Gênica de Plantas , Morus , Folhas de Planta , Proteínas de Plantas , Morus/genética , Morus/metabolismo , Flavonoides/metabolismo , Flavonoides/biossíntese , Folhas de Planta/metabolismo , Folhas de Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Superóxido Dismutase/metabolismo , Superóxido Dismutase/genética , Perfilação da Expressão Gênica , Quempferóis/metabolismo , Oxigenases de Função Mista , Oxirredutases
4.
Inhal Toxicol ; 35(7-8): 214-229, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37339372

RESUMO

BACKGROUND: Exposure to asbestos is associated with malignant and nonmalignant respiratory disease. To strengthen the scientific basis for risk assessment on fibers, the National Institute of Environmental Health Sciences (NIEHS) has initiated a series of studies to address fundamental questions on the toxicology of naturally occurring asbestos and related mineral fibers after inhalation exposure. A prototype nose-only exposure system was previously developed and validated. The prototype system was expanded to a large-scale exposure system in this study for conducting subsequent in vivo rodent inhalation studies of Libby amphibole (LA) 2007, selected as a model fiber. RESULTS: The exposure system consisting of six exposure carousels was able to independently deliver stable LA 2007 aerosol to individual carousels at target concentrations of 0 (control group), 0.1, 0.3, 1, 3, or 10 mg/m3. A single aerosol generator was used to provide aerosol to all carousels to ensure that exposure atmospheres were chemically and physically similar, with aerosol concentration as the only major variable among the carousels. Transmission electron microscopy (TEM) coupled with energy dispersive spectrometry (EDS) and selected area electron diffraction (SAED) analysis of aerosol samples collected at the exposure ports indicated the fiber dimensions, chemical composition, and mineralogy were equivalent across exposure carousels and were comparable to the bulk LA 2007 material. CONCLUSION: The exposure system developed is ready for use in conducting nose-only inhalation toxicity studies of LA 2007 in rats. The exposure system is anticipated to have applicability for the inhalation toxicity evaluation of other natural mineral fibers of concern.


Assuntos
Amiantos Anfibólicos , Amianto , Ratos , Animais , Amiantos Anfibólicos/toxicidade , Fibras Minerais , Aerossóis , Exposição por Inalação/efeitos adversos
5.
Inhal Toxicol ; 35(7-8): 201-213, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37339371

RESUMO

BACKGROUND: Asbestos has been classified as a human carcinogen, and exposure may increase the risk of diseases associated with impaired respiratory function. As the range of health effects and airborne concentrations that result in health effects across asbestos-related natural mineral fiber types are not fully understood, the National Institute of Environmental Health Sciences has established a series of research studies to characterize hazards of natural mineral fibers after inhalation exposure. This paper presents the method development work of this research project. RESULTS: A prototype nose-only exposure system was fabricated to explore the feasibility of generating natural mineral fiber aerosol for in vivo inhalation toxicity studies. The prototype system consisted of a slide bar aerosol generator, a distribution/delivery system and an exposure carousel. Characterization tests conducted using Libby Amphibole 2007 (LA 2007) demonstrated the prototype system delivered stable and controllable aerosol concentration to the exposure carousel. Transmission electron microscopy (TEM) analysis of aerosol samples collected at the exposure port showed the average fiber length and width were comparable to the bulk LA 2007. TEM coupled with energy dispersive spectrometry (EDS) and selected area electron diffraction (SAED) analysis further confirmed fibers from the aerosol samples were consistent with the bulk LA 2007 chemically and physically. CONCLUSIONS: Characterization of the prototype system demonstrated feasibility of generating LA 2007 fiber aerosols appropriate for in vivo inhalation toxicity studies. The methods developed in this study are suitable to apply to a multiple-carousel exposure system for a rat inhalation toxicity testing using LA 2007.


Assuntos
Amiantos Anfibólicos , Amianto , Humanos , Ratos , Animais , Amiantos Anfibólicos/toxicidade , Fibras Minerais , Amianto/análise , Carcinógenos/toxicidade , Aerossóis
6.
Neurosurg Rev ; 46(1): 305, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37982900

RESUMO

Treatment of blood blister-like aneurysms (BBAs) of the supraclinoid internal carotid artery (ICA) with flow diverters (FDs) has become widespread in recent years. However, ruptured blood blister-like aneurysm (BBA) of ICA treatment with flow diverter-assisted coil embolization (FDAC) remains controversial. Moreover, limited direct comparative studies have been conducted between the two treatment modalities, FDs and FDAC, for BBAs. The purpose of this study was to document our experience and evaluate the effectiveness and safety of FDAC. We conducted a retrospective analysis of clinical and radiological information from ten patients who experienced ruptured BBAs of the supraclinoid ICA at our center from January 2021 to February 2023. The technical details of FDAC for ruptured BBAs were described, and the technical steps were named "pipeline embolization device (PED)-Individualized shaping(microcatheter)-Semi deploying-Rivet(coils)-Massage(microwire)" as the PEISSERM technique. Clinical outcomes were assessed using the modified Rankin Scale (mRS), whereas radiological results were determined through angiography. A pooled analysis was implemented, incorporating data from literature sources that reported perioperative and long-term clinical and angiographic outcomes of ruptured BBAs treated with FD and FDAC strategies, along with our data. Data in our analysis pool were categorized into FD and FDAC strategy groups to explore the preferred treatment modalities for BBAs. The PEISSERM technique was utilized to treat ten patients, seven males, and three females, with an average age of 41.7 years. A single PED was deployed in conjunction with coils in all ten patients. All PEDs were documented to have good wall apposition. The immediate postoperative angiograms demonstrated Raymond grade I in ten aneurysms. Angiographic follow-up of nine patients at 4-25 months showed total occlusion of the aneurysms. At the most recent follow-up, the mRS scores of nine patients hinted at a good prognosis. Pooled analysis of 233 ICA-BBA cases of FD revealed a technical success rate of 91% [95% confidence interval (CI), 0.88 to 0.95], a rate of complete occlusion of 79% (95% CI, 0.73 to 0.84), a recurrence rate of 2% (95% CI, 0.00 to 0.04), a rebleed rate of 2% (95% CI, 0.00 to 0.04), and the perioperative stroke rate was 8% (95% CI, 0.04 to 0.11). The perioperative mortality was 4% (95% CI, 0.01 to 0.07). The long-term good clinical outcome rate was 85% (95% CI, 0.80 to 0.90). The mortality rate was 6% (95% CI, 0.03 to 0.09). Results from the subgroup analysis illustrated that the FDAC strategy for BBAs had a significantly higher immediate postoperative complete occlusion rate (P < 0.001), total occlusion rate (P = 0.016), and a good outcome rate (P = 0.041) compared with the FD strategy. The FDAC strategy can yield a higher rate of good outcomes than the FD strategy. The PEISSERM technique employed by the FDAC is a reliable and effective treatment approach as it can minimize the hemodynamic burden of BBA's fragile dome, thereby achieving an excellent occlusion rate. The PEISSERM technique in the FDAC strategy contributes to understanding the BBA's treatment and offers a potentially optimal treatment for BBA.


Assuntos
Aneurisma Roto , Artéria Carótida Interna , Feminino , Masculino , Humanos , Adulto , Artéria Carótida Interna/cirurgia , Estudos Retrospectivos , Aneurisma Roto/cirurgia , Angiografia , Prótese Vascular
7.
Heart Lung Circ ; 32(12): 1434-1442, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38042639

RESUMO

OBJECTIVE: This study systematically assessed circulating proteins to identify new serum biomarkers and risk of hypertension using Mendelian randomisation. METHODS: The associations between 4,782 human circulating proteins and the risk of hypertension were evaluated using two-sample Mendelian randomisation. The FinnGen study demonstrated a link between genetic predisposition and hypertension in 85,438 cases and 223,663 controls. RESULTS: Inverse variance weighted and sensitivity analysis revealed nine proteins in circulation that have a causative effect on hypertension. SMOC1 and TIE1 were determined to be causative factors in the decreased likelihood of developing hypertension, with odds ratios of 0.86 (95% CI 0.81-0.91; p=1.06e-06) and 0.96 (95% CI 0.94-0.98; p=9.39e-05), respectively. NDUFB4, ETHE1, POFUT2, TRIL, ADAM23, GXYLT1, OXT, TPST2, and TMCC3 showed a possible connection to hypertension. CONCLUSIONS: This two-sample Mendelian randomisation study found that SMOC1 and TIE1 are causally linked to hypertension, making them a promising target for therapy.


Assuntos
Hipertensão , Humanos , Biomarcadores , Hipertensão/epidemiologia , Hipertensão/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Estudo de Associação Genômica Ampla , Proteínas Mitocondriais , Proteínas de Transporte Nucleocitoplasmático
8.
J Neuroinflammation ; 19(1): 162, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35725625

RESUMO

BACKGROUND: Peripheral nerve inflammation or lesion can affect contralateral healthy structures, and thus result in mirror-image pain. Supraspinal structures play important roles in the occurrence of mirror pain. The anterior cingulate cortex (ACC) is a first-order cortical region that responds to painful stimuli. In the present study, we systematically investigate and compare the neuroimmune changes in the bilateral ACC region using unilateral- (spared nerve injury, SNI) and mirror-(L5 ventral root transection, L5-VRT) pain models, aiming to explore the potential supraspinal neuroimmune mechanism underlying the mirror-image pain. METHODS: The up-and-down method with von Frey hairs was used to measure the mechanical allodynia. Viral injections for the designer receptors exclusively activated by designer drugs (DREADD) were used to modulate ACC glutamatergic neurons. Immunohistochemistry, immunofluorescence, western blotting, protein microarray were used to detect the regulation of inflammatory signaling. RESULTS: Increased expressions of tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6) and chemokine CX3CL1 in ACC induced by unilateral nerve injury were observed on the contralateral side in the SNI group but on the bilateral side in the L5-VRT group, representing a stronger immune response to L5-VRT surgery. In remote ACC, both SNI and L5-VRT induced robust bilateral increase in the protein level of Nav1.6 (SCN8A), a major voltage-gated sodium channel (VGSC) that regulates neuronal activity in the mammalian nervous system. However, the L5-VRT-induced Nav1.6 response occurred at PO 3d, earlier than the SNI-induced one, 7 days after surgery. Modulating ACC glutamatergic neurons via DREADD-Gq or DREADD-Gi greatly changed the ACC CX3CL1 levels and the mechanical paw withdrawal threshold. Neutralization of endogenous ACC CX3CL1 by contralateral anti-CX3CL1 antibody attenuated the induction and the maintenance of mechanical allodynia and eliminated the upregulation of CX3CL1, TNF-α and Nav1.6 protein levels in ACC induced by SNI. Furthermore, contralateral ACC anti-CX3CL1 also inhibited the expression of ipsilateral spinal c-Fos, Iba1, CD11b, TNF-α and IL-6. CONCLUSIONS: The descending facilitation function mediated by CX3CL1 and its downstream cascade may play a pivotal role, leading to enhanced pain sensitization and even mirror-image pain. Strategies that target chemokine-mediated ACC hyperexcitability may lead to novel therapies for the treatment of neuropathic pain.


Assuntos
Hiperalgesia , Neuralgia , Animais , Gânglios Espinais/metabolismo , Giro do Cíngulo/metabolismo , Hiperalgesia/metabolismo , Interleucina-6/metabolismo , Mamíferos/metabolismo , Neuralgia/metabolismo , Doenças Neuroinflamatórias , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
9.
Neuroradiology ; 63(8): 1283-1292, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33611621

RESUMO

PURPOSE: The importance of supplementary motor area (SMA) for motor function and compensation for primary motor area (M1) has received increased attention. METHODS: We used diffusion tensor imaging (DTI) and transcranial magnetic stimulation (TMS) to evaluate structure and function of corticospinal projection originating from SMA. Fibers of corticospinal projection originating from M1 (CST) and SMA (ACST) were analyzed. ACST originating from mesial SMA area formed separate white matter bundles leaving the anterior part of M1 area, which then entered the posterior limb of the internal capsule. Projection and overlap of both CST and ACST were detected on medulla. RESULTS: Fibers of contralesional ACST were more than that of ipsilesional ACST in patients with SMA tumors (p<0.05). In patients with SMA tumor, all patients experienced temporary akinesia postoperatively. Seven hundred forty-one fibers of ipsilateral ACST and no fibers of ipsilateral CST were detected in the patient with M1 glioma, while most of contralateral limb movement was preserved. MEP could be evoked by stimulating SMA area as well as M1 area. ACST originated from SMA area and projected to the medial medulla. CONCLUSION: SMA area and ACST integrity contributed to contralateral motor function and were a compensation for M1 lesion and damaged CST.


Assuntos
Córtex Motor , Imagem de Tensor de Difusão , Humanos , Cápsula Interna , Córtex Motor/diagnóstico por imagem , Tratos Piramidais/diagnóstico por imagem , Estimulação Magnética Transcraniana
10.
Bioorg Chem ; 114: 105097, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34171594

RESUMO

Novel mansonone F derivative MSN54 (9-bromo-2,3-diethylbenzo[de]chromene-7,8-dione) exhibited significant cytotoxicity against twelve human tumor cell lines in vitro, with particularly strong potency against HL-60/MX2 cell line resistant to Topo II poisons. MSN54 was found to have IC50 of 0.69 and 1.43 µM against HL-60 and HL-60/MX2 cells, respectively. The resistance index is 10 times lower than that of the positive control VP-16 (etoposide). Various biological assays confirmed that MSN54 acted as a Topo IIα specific non-intercalative catalytic inhibitor. Furthermore, MSN54 exhibited good antitumor efficacy and low toxicity at a dose of 5 mg/kg in A549 tumor xenograft models. Thus, compound MSN54 is a promising candidate for the development of novel antitumor agents.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Ligação a Poli-ADP-Ribose/antagonistas & inibidores , Inibidores da Topoisomerase II/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA Topoisomerases Tipo II/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Relação Estrutura-Atividade , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/química
11.
Int J Mol Sci ; 21(8)2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32326149

RESUMO

Vasculogenesis and angiogenesis are physiological mechanisms occurring throughout the body. Any disruption to the precise balance of blood vessel growth necessary to support healthy tissue, and the inhibition of abnormal vessel sprouting has the potential to negatively impact stages of development and/or healing. Therefore, the identification of key regulators of these vascular processes is critical to identifying therapeutic means by which to target vascular-associated compromises and complications. Nuclear receptors are a family of transcription factors that have been shown to be involved in modulating different aspects of vascular biology in many tissues systems. Most recently, the role of nuclear receptors in ocular biology and vasculopathies has garnered interest. Herein, we review studies that have used in vitro assays and in vivo models to investigate nuclear receptor-driven pathways in two ocular vascular diseases associated with blindness, wet or exudative age-related macular degeneration, and proliferative diabetic retinopathy. The potential therapeutic targeting of nuclear receptors for ocular diseases is also discussed.


Assuntos
Suscetibilidade a Doenças , Neovascularização Patológica/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Biomarcadores , Gerenciamento Clínico , Humanos , Imuno-Histoquímica , Degeneração Macular/etiologia , Degeneração Macular/metabolismo , Degeneração Macular/patologia , Terapia de Alvo Molecular , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Neovascularização Retiniana/etiologia , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia , Transdução de Sinais
12.
Neurobiol Dis ; 130: 104456, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31028871

RESUMO

Injury associated pain involves subjective perception and emotional experience. The anterior cingulate cortex (ACC) is a key area involved in the affective component of pain processing. However, the neuroimmune mechanisms underlying enhanced ACC excitability following peripheral nerve injury are still not fully understood. Our previous work has shown that tumor necrosis factor-alpha (TNF-α) overexpression leads to peripheral afferent hyperexcitability and synaptic transmission potentiation in spinal cord. Here, we aimed to reveal the potential role of ACC TNF-α in ACC hyperexcitability and neuropathic pain. c-Fos, a widely used neuronal activity marker, was induced especially in contralateral ACC early [postoperative (PO) 1 h] and later (PO day 7 and 10) during the development of neuropathic pain. Spared nerve injury (SNI) elevated TNF-α level in contralateral ACC from PO day 5 to 14, delayed relative to decreased ipsilateral paw withdrawal threshold apparent from PO day 1 to 14. Microinjection of anti-TNF-α antibody into the ACC completely eliminated c-Fos overexpression and greatly attenuated pain aversion and mechanical allodynia induced by SNI, suggesting an important role of ACC TNF-α in the pain aversiveness and pain maintenance. Furthermore, modulating ACC pyramidal neurons via a Gi-coupled human M4 muscarinic receptor (hM4Di) or a Gq-coupled human M3 muscarinic receptor (hM3Dq), a type of designer receptors exclusively activated by designer drugs (DREADD), greatly changed the ACC TNF-α level and the mechanical paw withdrawal threshold. The positive interactions between TNF-α and ACC neurons might modulate the cytokine microenvironment thus contribute to the neuropathic pain.


Assuntos
Giro do Cíngulo/metabolismo , Neuralgia/metabolismo , Limiar da Dor/fisiologia , Células Piramidais/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Humanos , Hiperalgesia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Traumatismos dos Nervos Periféricos/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Sprague-Dawley , Regulação para Cima
13.
Opt Express ; 27(22): 32649-32658, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684473

RESUMO

We propose and experimentally demonstrate an ytterbium-doped fiber laser emitting the single high-order cylindrical vector beams with a high efficiency and a high modal purity based on adaptive modal gain control. By the combination of a high-order pump with a self-designed ytterbium-ring doped fiber, modal dependent gain was tailored and specific transverse mode can be selected in the laser cavity. A model based on multimode propagation-rate equations is built up to demonstrate the behaviors of transverse mode competition in the fiber laser. Modal dependent gain of high-order mode pump are simulated numerically, which agree well with our experiment results. The slope efficiency of the fiber laser reaches 79.61% with a low threshold of 47.73mw. The purity of the generated high-order CVBs are in excess of 95%. Such a strategy enables the controllability of modal gain in a fiber laser and reveals the potential to offer a new and promising way to achieve a high-power fiber laser with an arbitrary single high-order transverse modes output.

14.
Bioorg Chem ; 91: 103131, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31377387

RESUMO

For the development of novel anticancer agents, we designed and synthesized a total of 37 perimidine o-quinone derivatives containing the o-quinone group at the A or B ring and different substituents (alkyl groups, aryl groups or heterocycles) at the C ring of the compounds. The structure-activity relationships (SARs) were established based on the cytotoxicity data of compounds from the HL-60, Huh7, Hct116, and Hela cell lines. The cytotoxicity results showed that most compounds exhibited potent cytotoxicity. In particular, compound b-12 showed the best anti-proliferative activity (IC50 ≤ 1 µM) against four cancer cell lines and strong potency against the HL-60/MX2 (0.47 µM) cell line, which is resistant to Topo II poisons. Further studies showed that b-12 exhibited potent Topo IIα inhibitory activity (IC50 = 7.54 µM) compared with Topo I, which acted as a class of non-intercalative Topo IIα catalytic inhibitor by inhibiting the ATP binding site of Topo II. Cell apoptosis and cell cycle assays confirmed that b-12 could induce the apoptosis of Huh7 cells in a dose-dependent manner.


Assuntos
Antineoplásicos/farmacologia , Quinazolinas/farmacologia , Quinonas/farmacologia , Inibidores da Topoisomerase II/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA Topoisomerases Tipo II/química , DNA Topoisomerases Tipo II/metabolismo , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Ligação Proteica , Quinazolinas/síntese química , Quinazolinas/metabolismo , Quinonas/síntese química , Quinonas/metabolismo , Relação Estrutura-Atividade , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/metabolismo
15.
Appl Opt ; 58(30): 8290-8294, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674501

RESUMO

This study proposes a new method for the preparation of novel MXenes/metal composites with unique chemical properties using reducing agent action. The effect of the reduction reaction time on the preparation conditions of ${{\rm Ti}_3}{{\rm C}_2}{{\rm T}_x}/{\rm Au}$Ti3C2Tx/Au nanocomposites is studied, and the contribution of the prepared nanocomposites to the surface Raman reinforcement is analyzed. This study further explores the application of MXene in surface-enhanced Raman spectroscopy.

16.
Neurocrit Care ; 31(3): 501-506, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31161421

RESUMO

BACKGROUND AND OBJECTIVE: The aim of the study is to investigate the value of serum iron and hemoglobin levels for predicting acute seizures following aneurysmal subarachnoid hemorrhage (aSAH). METHODS: Clinical and laboratorial data from patients with ruptured intracranial aneurysms were collected in the retrospective study. Age, sex, symptom onset, history of diabetes and hypertension, history of coronary artery disease, temperature, Hunt-Hess grade, Fisher grade, aneurysm location, hemoglobin, serum potassium, sodium, calcium, phosphorus, and iron were collected. Acute seizures were determined as seizures within 1 week following aSAH. Propensity score matching (PSM) analyses were performed to correct imbalances in patient characteristics between seizure and non-seizure groups. RESULTS: A total of 760 patients were included. Incidence of acute seizures following aSAH was 6.4%. In the univariate analysis, significant differences were detected in age, admission Hunt-Hess grade, Fisher grade, hemoglobin, serum sodium, and serum iron between seizure and non-seizure groups. In multivariate logistic regression model, lower serum iron was considered as a risk factor for acute seizures (OR 0.182, 95% CI 0.084-0.393, p = 0.000), as well as lower hemoglobin (OR 0.977, 95% CI 0.962-0.993, p = 0.004) and higher serum sodium (OR 1.072, 95% CI 1.003-1.145, p = 0.039). After PSM, there were no significant differences in age, admission Hunt-Hess grade, Fisher grade, and serum sodium between seizure and non-seizure groups. The matched seizure group had lower serum iron and hemoglobin levels compared with the matched non-seizure group (p < 0.05). The optimal cutoff value for serum iron and hemoglobin levels as a predictor of acute seizure after aSAH was determined as 9.9 mmol/L (sensitivity was 81.63% and the specificity was 65.40%) and 119 g/L (sensitivity was 63.27% and the specificity was 70.18%), respectively. CONCLUSIONS: Serum iron and hemoglobin levels were inversely associated with a high risk of acute seizures following aSAH.


Assuntos
Anemia Ferropriva/sangue , Hemoglobinas/metabolismo , Ferro/sangue , Convulsões/sangue , Hemorragia Subaracnóidea/sangue , Adulto , Anemia/sangue , Anemia/epidemiologia , Anemia Ferropriva/epidemiologia , Feminino , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Ruptura Espontânea , Convulsões/epidemiologia , Convulsões/etiologia , Hemorragia Subaracnóidea/epidemiologia , Hemorragia Subaracnóidea/etiologia , Hemorragia Subaracnóidea/fisiopatologia
17.
J Neurochem ; 145(2): 154-169, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29423951

RESUMO

Previous work from our laboratory showed that motor nerve injury by lumbar 5 ventral root transection (L5-VRT) led to interleukin-6 (IL-6) over-expression in bilateral spinal cord, and that intrathecal administration of IL-6 neutralizing antibody delayed the induction of mechanical allodynia in bilateral hind paws. However, early events and upstream mechanisms underlying spinal IL-6 expression following L5-VRT require elucidation. The model of L5-VRT was used to induce neuropathic pain, which was assessed with von Frey hairs and the plantar tester in adult male Sprague-Dawley rats. Calpain-2 (CALP2, a calcium-dependent protease) knockdown or over-expression and microglia depletion were conducted intrathecally. Western blots and immunohistochemistry were performed to explore the possible mechanisms. Here, we provide the first evidence that both IL-6 and CALP2 levels are increased in lumbar spinal cord within 30 min following L5-VRT. IL-6 and CALP2 co-localized in both spinal dorsal horn (SDH) and spinal ventral horn. Post-operative (PO) increase in CALP2 in ipsilateral SDH was evident at 10 min PO, preceding increased IL-6 at 20 min PO. Knockdown of spinal CALP2 by intrathecal CALP2-shRNA administration prevented VRT-induced IL-6 overproduction in ipsilateral spinal cord and alleviated bilateral mechanical allodynia. Spinal microglia activation also played a role in early IL-6 up-regulation. Macrophage/microglia markers ED1/Iba1 were increased at 30 min PO, while glial fibrillary acidic protein (astrocyte) and CNPase (oligodendrocyte) markers were not. Increased Iba1 was detected as early as 20 min PO and peaked at 3 days. Morphology changed from a small soma with fine processes in resting cells to an activated ameboid shape. Depletion of microglia using Mac-1-saporin partially prevented IL-6 up-regulation and attenuated VRT-induced bilateral mechanical allodynia. Taken together, our findings provide evidence that increased spinal cord CALP2 and microglia cell activation may have early causative roles in IL-6 over-expression following motor nerve injury. Agents that inhibit CALP2 and/or microglia activation may therefore prove valuable for treating neuropathic pain.


Assuntos
Calpaína/biossíntese , Interleucina-6/biossíntese , Microglia/metabolismo , Neurônios Motores/metabolismo , Neuralgia/metabolismo , Raízes Nervosas Espinhais/lesões , Animais , Axotomia , Hiperalgesia/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Medula Espinal/metabolismo , Raízes Nervosas Espinhais/metabolismo , Regulação para Cima
19.
J Biol Chem ; 291(48): 25255-25263, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27765815

RESUMO

Alcoholic liver disease is a pathological condition caused by overconsumption of alcohol. Because of the high morbidity and mortality associated with this disease, there remains a need to elucidate the molecular mechanisms underlying its etiology and to develop new treatments. Because peroxisome proliferator-activated receptor-ß/δ (PPARß/δ) modulates ethanol-induced hepatic effects, the present study examined alterations in gene expression that may contribute to this disease. Chronic ethanol treatment causes increased hepatic CYP2B10 expression inPparß/δ+/+ mice but not in Pparß/δ-/- mice. Nuclear and cytosolic localization of the constitutive androstane receptor (CAR), a transcription factor known to regulate Cyp2b10 expression, was not different between genotypes. PPARγ co-activator 1α, a co-activator of both CAR and PPARß/δ, was up-regulated in Pparß/δ+/+ liver following ethanol exposure, but not in Pparß/δ-/- liver. Functional mapping of the Cyp2b10 promoter and ChIP assays revealed that PPARß/δ-dependent modulation of SP1 promoter occupancy up-regulated Cyp2b10 expression in response to ethanol. These results suggest that PPARß/δ regulates Cyp2b10 expression indirectly by modulating SP1 and PPARγ co-activator 1α expression and/or activity independent of CAR activity. Ligand activation of PPARß/δ attenuates ethanol-induced Cyp2b10 expression in Pparß/δ+/+ liver but not in Pparß/δ-/- liver. Strikingly, Cyp2b10 suppression by ligand activation of PPARß/δ following ethanol treatment occurred in hepatocytes and was mediated by paracrine signaling from Kupffer cells. Combined, results from the present study demonstrate a novel regulatory role of PPARß/δ in modulating CYP2B10 that may contribute to the etiology of alcoholic liver disease.


Assuntos
Hidrocarboneto de Aril Hidroxilases/biossíntese , Família 2 do Citocromo P450/biossíntese , Regulação Enzimológica da Expressão Gênica , Hepatopatias Alcoólicas/metabolismo , Fígado/metabolismo , PPAR delta/metabolismo , PPAR beta/metabolismo , Regiões Promotoras Genéticas , Fator de Transcrição Sp1/metabolismo , Esteroide Hidroxilases/biossíntese , Animais , Hidrocarboneto de Aril Hidroxilases/genética , Família 2 do Citocromo P450/genética , Etanol/toxicidade , Hepatócitos/metabolismo , Hepatócitos/patologia , Células de Kupffer/metabolismo , Células de Kupffer/patologia , Fígado/patologia , Hepatopatias Alcoólicas/genética , Hepatopatias Alcoólicas/patologia , Camundongos , Camundongos Knockout , PPAR delta/genética , PPAR beta/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Transcrição Sp1/genética , Esteroide Hidroxilases/genética
20.
Immunology ; 150(4): 456-467, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27935639

RESUMO

The peroxisome proliferator-activated receptor-ß/δ (PPARß/δ) is known to have multiple anti-inflammatory effects, typically observed in endothelial cells, macrophages, T cells and B cells. Despite the fact that mast cells are important mediators of inflammation, to date, the role of PPARß/δ in mast cells has not been examined. Hence, the present study examined the hypothesis that PPARß/δ modulates mast cell phenotype. Bone-marrow-derived mast cells (BMMCs) and peritoneal mast cells from Pparß/δ+/+ mice expressed higher levels of high-affinity IgE receptor (FcεRI) compared with Pparß/δ-/- mice. BMMCs from Pparß/δ+/+ mice also exhibited dense granules, associated with higher expression of enzymes and proteases compared with Pparß/δ-/- mice. Resting BMMCs from Pparß/δ+/+ mice secreted lower levels of inflammatory cytokines, associated with the altered activation of phospholipase Cγ1 and extracellular signal-regulated kinases compared with Pparß/δ-/- mice. Moreover, the production of cytokines by mast cells induced by various stimuli was highly dependent on PPARß/δ expression. This study demonstrates that PPARß/δ is an important regulator of mast cell phenotype.


Assuntos
Células da Medula Óssea/fisiologia , Diferenciação Celular , Mastócitos/fisiologia , PPAR delta/metabolismo , PPAR beta/metabolismo , Animais , Células Cultivadas , Citocinas/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , PPAR delta/genética , PPAR beta/genética , Fenótipo , Receptores de IgE/genética , Receptores de IgE/metabolismo , Transdução de Sinais/genética
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