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1.
ACS Appl Bio Mater ; 7(6): 3629-3635, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38817210

RESUMO

We prepared composite electrodes using TiO2 coated with chlorophylls a and b as photoelectric conversion material and MnO2 as energy storage material and investigated their photoelectrochemical capacitor properties. The coating with the combination of chlorophylls a and b improved the photoelectric conversion function of TiO2, compared with the coating with each alone. Na+ adsorption on MnO2 was enhanced with increasing the chlorophyll coating amount. The reason is that more chlorophylls a and b absorb visible light in different wavelengths to promote an easier photoexcited electron transfer to MnO2, just as they improve the efficiency of photosynthesis reactions in nature.


Assuntos
Clorofila , Eletrodos , Compostos de Manganês , Teste de Materiais , Óxidos , Tamanho da Partícula , Titânio , Titânio/química , Compostos de Manganês/química , Óxidos/química , Clorofila/química , Técnicas Eletroquímicas , Propriedades de Superfície
3.
Artigo em Inglês | MEDLINE | ID: mdl-34429366

RESUMO

BACKGROUND AND OBJECTIVE: To elucidate the relationship between melanoma cell adhesion molecule (MCAM)-expressing lymphocytes and pathogenesis of CNS inflammatory demyelinating diseases (IDDs). METHODS: Patients with multiple sclerosis (MS) (n = 72) and neuromyelitis optica spectrum disorder (NMOSD, n = 29) were included. We analyzed the frequency and absolute numbers of MCAM+ lymphocytes (memory helper T [mTh] cells, naive helper T cells, CD8+ T cells, and B cells) in the peripheral blood (PB) and the CSF of patients with MS and NMOSD, treated with/without disease-modifying drugs (DMDs) or steroids, using flow cytometry. RESULTS: The frequency of MCAM+ cells was higher in the mTh cell subset than that in other lymphocyte subsets. A significant increase in the frequency and the absolute number of MCAM+ mTh cells was observed in the PB of patients with NMOSD, whereas no increase was observed in the PB of patients with MS. The frequency of CSF MCAM+ mTh cells was higher in relapsing patients with MS and NMOSD than that in the control group. Although there was no difference in the frequencies of MCAM+ lymphocytes among the DMD-treated groups, fingolimod decreased the absolute number of MCAM+ lymphocytes. DISCUSSION: MCAM+ mTh cells were elevated in the CSF of relapsing patients with MS and in both the PB and CSF of patients with NMOSD. These results indicate that MCAM contributes to the pathogenesis of MS and NMOSD through different mechanisms. MCAM could be a therapeutic target of CNS IDDs, and further study is needed to elucidate the underlying mechanism of MCAM in CNS IDD pathogenesis.


Assuntos
Esclerose Múltipla , Neuromielite Óptica , Linfócitos T Auxiliares-Indutores/metabolismo , Adulto , Idoso , Antígeno CD146/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/sangue , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/imunologia , Esclerose Múltipla/metabolismo , Esclerose Múltipla Recidivante-Remitente/sangue , Esclerose Múltipla Recidivante-Remitente/líquido cefalorraquidiano , Esclerose Múltipla Recidivante-Remitente/imunologia , Miastenia Gravis/sangue , Miastenia Gravis/líquido cefalorraquidiano , Miastenia Gravis/imunologia , Neuromielite Óptica/sangue , Neuromielite Óptica/líquido cefalorraquidiano , Neuromielite Óptica/imunologia , Adulto Jovem
4.
Sci Rep ; 11(1): 7053, 2021 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-33782421

RESUMO

Metformin is widely used for the treatment of type 2 diabetes, and increasing numbers of studies have shown that metformin also ameliorates tumor progression, inflammatory disease, and fibrosis. However, the ability of metformin to improve non-diabetic glomerular disease and chronic kidney disease (CKD) has not been explored. To investigate the effect of metformin on non-diabetic glomerular disease, we used a mouse model of Alport syndrome (Col4a5 G5X) which were treated with metformin or losartan, used as a control treatment. We also investigated the effect of metformin on adriamycin-induced glomerulosclerosis model. Pathological and biochemical analysis showed that metformin or losartan suppressed proteinuria, renal inflammation, fibrosis, and glomerular injury and extended the lifespan in Alport syndrome mice. Transcriptome analysis showed that metformin and losartan influenced molecular pathways-related to metabolism and inflammation. Metformin altered multiple genes including metabolic genes not affected by losartan. Metformin also suppressed proteinuria and glomerular injury in the adriamycin-induced glomerulosclerosis mouse model. Our results showed that metformin ameliorates the glomerular sclerosis and CKD phenotype in non-diabetic chronic glomerular diseases. Metformin may have therapeutic potential for not only diabetic nephropathy but also non-diabetic glomerular disease including Alport syndrome.


Assuntos
Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Nefrite Hereditária/tratamento farmacológico , Animais , Colágeno Tipo IV/genética , Nefropatias Diabéticas/fisiopatologia , Nefropatias Diabéticas/prevenção & controle , Modelos Animais de Doenças , Rim/metabolismo , Camundongos , Nefrite Hereditária/genética , Nefrite Hereditária/fisiopatologia , Fenótipo , Índice de Gravidade de Doença , Transdução de Sinais , Transcriptoma
5.
ChemSusChem ; 14(4): 1166-1175, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33369231

RESUMO

Potassium manganese hexacyanoferrate (KMnHCF) can be used as a positive electrode for potassium-ion batteries because of its high energy density. The effect of particle size and [Fe(CN)6 ]n- vacancies on the electrochemical potassium insertion of KMnHCFs was examined through experimental data and theoretical calculations. When nearly stoichiometric KMnHCF was synthesized and tested, smaller particle sizes were found to be important for achieving superior electrochemical performance in terms of capacity and rate capability. However, even in the case of larger particles, introducing a suitable number of anion vacancies enabled KMnHCF to exhibit comparable electrode performance. Electrochemical tests and density functional theory calculations indicated that anion vacancies contribute to the enhancement of K+ ion diffusion, which realizes good electrochemical performance. Structural design, including crystal vacancies and particle size, is the key to their high performance as a positive electrode.

6.
ACS Appl Bio Mater ; 4(8): 5975-5980, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35006912

RESUMO

A TiO2 electrode was coated with chlorophyll a to regenerate nicotinamide adenine dinucleotide phosphate (NADPH), which can enhance the photovoltages of the electrodes for photoelectrochemical capacitors. The photovoltage of an uncoated TiO2 electrode was high during the first cycle but then steadily reduced owing to the oxidization of NADPH in the electrolyte during the photo-charge-discharge cycling. By contrast, a chlorophyll a-coated TiO2 electrode maintained high photovoltages for 100 cycles. Residual NADPH concentrations after 100 cycles increased from 73% to 90% because of the coating, demonstrating that NADPH was regenerated by photoexcited chlorophyll a similar to a photosynthetic reaction in nature.


Assuntos
Regeneração , Clorofila A , Eletrodos , NADP , Titânio
7.
Chem Commun (Camb) ; 54(60): 8387-8390, 2018 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-29998275

RESUMO

Stable cycling of a 4 V-class potassium-ion battery is demonstrated with a highly concentrated potassium bis(fluorosulfonyl)amide 1,2-dimethoxyethane solution as an electrolyte. Not only graphite and K2Mn[Fe(CN)6] half cells but also graphite//K2Mn[Fe(CN)6] full cells filled with the electrolyte exhibit higher coulombic efficiency and better cyclability than those of KPF6/carbonate ester solutions.

8.
Org Biomol Chem ; 16(14): 2397-2401, 2018 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-29561016

RESUMO

We have developed a novel analog of the GFP chromophore: geo-DAIN. Since geo-DAIN is equipped with an E/Z-photoisomerizable geometrical diarylmethylene moiety instead of benzylidene of the GFP chromophore, different-colored reversible emissions are expected. We synthesized geo-DAIN by a condensation with methyl imidate and N-(diarylmethylene)glycinate. We found the emission from geo-DAIN to be different from that of benzylidene-type analogs; in the powder state, the E- and Z-isomers of geo-DAIN emitted different fluorescence colors.


Assuntos
Compostos de Benzilideno/química , Imidazolinas/química , Compostos de Benzilideno/síntese química , Compostos de Benzilideno/efeitos da radiação , Fluorescência , Proteínas de Fluorescência Verde/química , Imidazolinas/síntese química , Imidazolinas/efeitos da radiação , Isomerismo , Raios Ultravioleta
9.
Cell Chem Biol ; 25(5): 634-643.e4, 2018 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-29526710

RESUMO

Alport syndrome is a hereditary glomerular disease caused by mutation in type IV collagen α3-α5 chains (α3-α5(IV)), which disrupts trimerization, leading to glomerular basement membrane degeneration. Correcting the trimerization of α3/α4/α5 chain is a feasible therapeutic approach, but is hindered by lack of information on the regulation of intracellular α(IV) chain and the absence of high-throughput screening (HTS) platforms to assess α345(IV) trimer formation. Here, we developed sets of split NanoLuc-fusion α345(IV) proteins to monitor α345(IV) trimerization of wild-type and clinically associated mutant α5(IV). The α345(IV) trimer assay, which satisfied the acceptance criteria for HTS, enabled the characterization of intracellular- and secretion-dependent defects of mutant α5(IV). Small interfering RNA-based and chemical screening targeting the ER identified several chemical chaperones that have potential to promote α345(IV) trimer formation. This split luciferase-based trimer formation assay is a functional HTS platform that realizes the feasibility of targeting α345(IV) trimers to treat Alport syndrome.


Assuntos
Autoantígenos/química , Colágeno Tipo IV/química , Avaliação Pré-Clínica de Medicamentos/métodos , Nefrite Hereditária/tratamento farmacológico , Multimerização Proteica/efeitos dos fármacos , Autoantígenos/genética , Colágeno Tipo IV/genética , Células HEK293 , Ensaios de Triagem em Larga Escala/métodos , Humanos , Nefrite Hereditária/genética , Mutação Puntual
10.
Nephrol Dial Transplant ; 33(2): 214-223, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28992339

RESUMO

Background: Alport syndrome (AS) is a hereditary, progressive nephritis caused by mutation of type IV collagen. Previous studies have shown that activation of signal transducer and activator of transcription 3 (STAT3) exacerbates other renal diseases, but whether STAT3 activation exacerbates AS pathology is still unknown. Here we aim to investigate the involvement of STAT3 in the progression of AS. Method: Phosphorylated STAT3 expression was assessed by immunoblotting analysis of kidneys and glomeruli of an AS mouse model (Col4a5 G5X mutant). To determine the effect of blocking STAT3 signaling, we treated AS mice with the STAT3 inhibitor stattic (10 mg/kg i.p., three times per week for 10 weeks; n = 10). We assessed the renal function [proteinuria, blood urea nitrogen (BUN), serum creatinine] and analyzed the glomerular injury score, fibrosis and inflammatory cell invasion by histological staining. Moreover, we analyzed the gene expression of nephritis-associated molecules. Results: Phosphorylated STAT3 was upregulated in AS kidneys and glomeruli. Treatment with stattic ameliorated the progressive renal dysfunction, such as increased levels of proteinuria, BUN and serum creatinine. Stattic also significantly suppressed the gene expression levels of renal injury markers (Lcn2, Kim-1), pro-inflammatory cytokines (Il-6, KC), pro-fibrotic genes (Tgf-ß, Col1a1, α-Sma) and Mmp9. Stattic treatment decreased the renal fibrosis congruently with the decrease of transforming growth factor beta (TGF-ß) protein and increase of antifibrosis-associated markers p-Smad1, 5 and 8, which are negative regulators of TGF-ß signaling. Conclusion: STAT3 inhibition significantly ameliorated the renal dysfunction in AS mice. Our finding identifies STAT3 as an important regulator in AS progression and provides a promising therapeutic target for AS.


Assuntos
Modelos Animais de Doenças , Fibrose/prevenção & controle , Inflamação/prevenção & controle , Nefrite Hereditária/complicações , Insuficiência Renal/prevenção & controle , Fator de Transcrição STAT3/antagonistas & inibidores , Animais , Progressão da Doença , Fibrose/etiologia , Fibrose/metabolismo , Fibrose/patologia , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nefrite Hereditária/metabolismo , Nefrite Hereditária/patologia , Fenótipo , Insuficiência Renal/etiologia , Insuficiência Renal/metabolismo , Insuficiência Renal/patologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
11.
PLoS One ; 12(9): e0183959, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28873450

RESUMO

A seminal study recently demonstrated that bromide (Br-) has a critical function in the assembly of type IV collagen in basement membrane (BM), and suggested that Br- supplementation has therapeutic potential for BM diseases. Because salts of bromide (KBr and NaBr) have been used as antiepileptic drugs for several decades, repositioning of Br- for BM diseases is probable. However, the effects of Br- on glomerular basement membrane (GBM) disease such as Alport syndrome (AS) and its impact on the kidney are still unknown. In this study, we administered daily for 16 weeks 75 mg/kg or 250 mg/kg (within clinical dosage) NaBr or NaCl (control) via drinking water to 6-week-old AS mice (mouse model of X-linked AS). Treatment with 75 mg/kg NaBr had no effect on AS progression. Surprisingly, compared with 250 mg/kg NaCl, 250 mg/kg NaBr exacerbated the progressive proteinuria and increased the serum creatinine and blood urea nitrogen in AS mice. Histological analysis revealed that glomerular injury, renal inflammation and fibrosis were exacerbated in mice treated with 250 mg/kg NaBr compared with NaCl. The expressions of renal injury markers (Lcn2, Lysozyme), matrix metalloproteinase (Mmp-12), pro-inflammatory cytokines (Il-6, Il-8, Tnf-α, Il-1ß) and pro-fibrotic genes (Tgf-ß, Col1a1, α-Sma) were also exacerbated by 250 mg/kg NaBr treatment. Notably, the exacerbating effects of Br- were not observed in wild-type mice. These findings suggest that Br- supplementation needs to be carefully evaluated for real positive health benefits and for the absence of adverse side effects especially in GBM diseases such as AS.


Assuntos
Brometos/efeitos adversos , Nefropatias/metabolismo , Cirrose Hepática , Nefrite Hereditária/metabolismo , Animais , Nitrogênio da Ureia Sanguínea , Brometos/farmacologia , Creatinina/sangue , Modelos Animais de Doenças , Membrana Basal Glomerular/patologia , Rim/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nefrite/patologia , Nitrogênio/sangue , Compostos de Potássio/efeitos adversos , Compostos de Potássio/farmacologia , Proteinúria/metabolismo , Compostos de Sódio/efeitos adversos , Compostos de Sódio/farmacologia
12.
J Toxicol Pathol ; 29(2): 131-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27182119

RESUMO

The aim of this study was to examine the possible involvement of smooth muscle cell remodeling and the induction of MFG-E8 (milk fat globule protein epidermal growth factor-VIII) in vascular pathophysiology during cocaine administration in cultured cells and rats. Cocaine exerts bifurcate effects on vascular cells; it stimulates vasoconstriction through enhancement of catecholamine release at low doses, while it suppresses cardiovascular functions through inhibition of ion channels at high doses. Short-term exposure to a high concentration of cocaine (3 mM, 24 hr) resulted in cell death of A7r5 rat aorta-derived smooth muscle cells. On the other hand, long-term exposure of the same cells to a low concentration (0.3 mM, ~7 days) resulted in a transient increase in MFG-E8 expression followed by an increased tendency toward cyclin D1, PCNA (proliferating cell nuclear antigen), and CDK4 (cyclin-dependent protein kinase-4) expression. Interestingly, autophagy was not induced, but rather was impaired, in cocaine-treated cells. Increased expressions of MFG-E8, PCNA, and CDK4 were also observed in the aortic vascular cells of rats administered cocaine (50 mg/kg, 2 days, i.v.), confirming that cocaine induced MFG-E8 expression in vivo. Taken together, the results show that MFG-E8 is induced in vascular cells exposed to cocaine, and that this induction is likely to be involved in the vascular toxicity elicited by cocaine abuse.

13.
J Forensic Leg Med ; 22: 90-2, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24485430

RESUMO

A man, who had a medical history of surgical neck clipping 30 years previously, died of traffic accident. The medico-legal autopsy showed subarachnoid hemorrhage and ruptured aneurysm on the lateral side of the clip. Microscopic examination showed the aneurysm was not to be regeneration, but a new de novo aneurysm. We diagnosed the cause of death was traumatic aneurysmal rupture. In addition, we discussed the cause of a newly formed de novo aneurysm which may be affected by past surgical neck clipping.


Assuntos
Aneurisma Roto/patologia , Aneurisma Intracraniano/patologia , Aneurisma Intracraniano/cirurgia , Hemorragia Subaracnoídea Traumática/patologia , Instrumentos Cirúrgicos , Acidentes de Trânsito , Idoso , Evolução Fatal , Patologia Legal , Humanos , Imageamento Tridimensional , Aneurisma Intracraniano/diagnóstico por imagem , Masculino , Tomografia Computadorizada por Raios X , Procedimentos Cirúrgicos Vasculares
14.
Geriatr Gerontol Int ; 14(2): 498-507, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23879479

RESUMO

AIMS: The relationship between hydroxyl radical (·OH) and oxidatively modified macromolecule formations was examined in tissues from young and aged mice. METHODS: To determine the ·OH generation in tissues in vivo using the hydroxylation trapping reaction of ·OH into salicylic acid (SA), analytical conditions for dihydroxybenzoic acid (DHBA) and SA determination, and optimum dosages of SA for administration and time-points of tissue sampling were determined. 2, 3-DHBA levels in tissues from young mice and age-related changes were determined with the oxidatively modified macromolecules. RESULTS: 2, 3-DHBA, a hydroxylation compound of SA, is considered to be suitable for determination of ·OH levels in tissues. Tissue levels of 2, 3-DHBA expressed as a molar ratio to SA, was comparable among tissues, and was in accordance with 8-oxo-2'-deoxyguanosine (8-oxodG) and carbonylated proteins. In the aging process, 2, 3-DHBA levels in the brain and heart increased in the biphasic pattern in accordance with the 8-oxodG and thiobarbituric acid reactive substances (TBARS) levels, whereas levels of carbonylated proteins were not changed with age. CONCLUSIONS: An in vivo method for ·OH measurement using hydroxylation of SA was optimized. However, as a limitation, 2, 3-DHBA, as well as other oxidative stress markers, could be affected by various in vivo factors. The accordance was seen among 2, 3-DHBA, 8-oxodG and carbonylated protein levels in tissues from young mice. The tissue levels of 2, 3-DHBA increased in accordance with the 8-oxodG and TBARS during the aging process.


Assuntos
Radical Hidroxila/metabolismo , Substâncias Macromoleculares/metabolismo , Fatores Etários , Animais , Hidroxilação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ácido Salicílico/metabolismo
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