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1.
Dig Surg ; 41(1): 30-36, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38219712

RESUMO

INTRODUCTION: The usefulness of gadolinium-ethoxybenzyl diethylenetriamine pentaacetate acid-enhanced magnetic resonance imaging (EOB-MRI) in assessing the functional future remnant liver volume (fFRLV) to predict post-hepatectomy liver failure (PHLF) has been previously reported. Herein, we evaluated the efficacy of this technique in patients with hepatocellular carcinoma (HCC) with a major portal vein tumor thrombus (PVTT). METHODS: This study included 21 patients with PVTT in the ipsilateral first-order branch (Vp3) and 30 patients with PVTT in the main trunk/contralateral branch (Vp4). To evaluate fFRLV, the signal intensity (SI) of the remnant liver was determined on T1-weighted images, using both conventional and newly developed methods. The fFRLV was calculated using the SI of the remnant liver and muscle, remnant liver volume, and body surface area. Preoperative factors predicting PHLF (≥grade B) in HCC patients with Vp3/4 PVTT were evaluated. RESULTS: In the Vp3 group, we found fFRLV area under the receiver-operating characteristic curves (AUCs) above 0.70 (AUC = 0.875, 0.750) using EOB-MRI results calculated using either the plot or whole method. None of the parameters in the Vp4 group had an AUC greater than 0.70. CONCLUSION: The fFRLV calculated by EOB-MRI using the whole method can be as useful as the conventional method in predicting PHLF (≥grade B) for HCC patients with Vp3 PVTT.


Assuntos
Carcinoma Hepatocelular , Falência Hepática , Neoplasias Hepáticas , Poliaminas , Trombose , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/patologia , Hepatectomia/métodos , Veia Porta/cirurgia , Gadolínio , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Trombose/patologia , Trombose/cirurgia , Falência Hepática/diagnóstico por imagem , Falência Hepática/etiologia , Imageamento por Ressonância Magnética , Estudos Retrospectivos
2.
Bioorg Med Chem ; 99: 117597, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38262305

RESUMO

Ten-Eleven Translocation (TET) enzymes are Fe(II)/2OG-dependent oxygenases that play important roles in epigenetic regulation, but selective inhibition of the TETs is an unmet challenge. We describe the profiling of previously identified TET1-binding macrocyclic peptides. TiP1 is established as a potent TET1 inhibitor (IC50 = 0.26 µM) with excellent selectivity over other TETs and 2OG oxygenases. TiP1 alanine scanning reveals the critical roles of Trp10 and Glu11 residues for inhibition of TET isoenzymes. The results highlight the utility of the RaPID method to identify potent enzyme inhibitors with selectivity over closely related paralogues. The structure-activity relationship data generated herein may find utility in the development of chemical probes for the TETs.


Assuntos
Dioxigenases , Peptídeos Cíclicos , Humanos , Epigênese Genética , Proteínas de Ligação a DNA/metabolismo , Oxigenases de Função Mista/metabolismo , Dioxigenases/metabolismo , Metilação de DNA , Proteínas Proto-Oncogênicas
3.
Membranes (Basel) ; 13(1)2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36676922

RESUMO

Recently, polymer electrolytes have been developed for high-performance and eco-friendly fuel cells. Among the candidates, eggshell membrane (ESM) has been promising because of its abundance to assemble various energy devices with low cost and its absorption ability of organic materials. In this work, we investigated fuel cells that included ESM-absorbing xanthene-, triphenylmethane-, and azo-type tar dye, which contained abundant hydrophilic groups, as polymer electrolytes. We found out two points: (1) that the fuel cells that included ESM-absorbing xanthene-type dye generated the highest I-V performance, and (2) the basic molecular structures of the tar dyes determined the correlation of the maximum power and proton conductivities.

4.
Polymers (Basel) ; 15(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36679217

RESUMO

Recently, organic polysulfides have been synthesized as cathode active materials exceeding the battery performance of sulfur. However, the conventional organic polysulfides have exhibited capacities lower than the theoretical capacity of sulfur because the π-organic moieties do not conjugate with the sulfur chains. In this work, the organopolysulfides, synthesized via inverse vulcanization using disulfide compounds, exhibited higher capacities equal to the theoretical capacity of sulfur because of enhanced electronic conductivity based on the conjugation between organic moieties and sulfur chains. Furthermore, the organopolysulfide including 1,3-dhitiol-2-thione moiety exhibited the highest capacity because of the enhanced electronic conductivity. This finding will pave the way to develop next-generation rechargeable batteries.

5.
J Am Chem Soc ; 144(44): 20171-20176, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36306265

RESUMO

Visible light, particularly in the blue region of the spectrum, can cause cell dysfunction through the generation of singlet oxygen, contributing to cellular aging and age-related pathologies. Although photooxidation of nucleic acids, lipids, and amino acids has been extensively studied, the magnitude and span of blue-light-induced protein damages within proteome remain largely unknown. Herein we present a chemoproteomic approach to mapping blue-light-damaged proteins in live mammalian cells by exploiting a nucleophilic alkyne chemical probe. A gene ontology enrichment analysis revealed that cell surface proteins are more readily oxidized than other susceptible sets of proteins, including mitochondrial proteins. In particular, the integrin family of cell surface receptors (ITGs) was highly ranked in the mammalian cells tested, including human corneal endothelial cells. The blue-light-oxidized ITGB1 protein was functionally inactive in promoting cell adhesion and proliferation, suggesting that the photodamage of integrins contributes to the blue-light-induced cell dysfunction. Further application of our method to various cells and tissues should lead to a comprehensive analysis of light-sensitive proteins.


Assuntos
Células Endoteliais , Oxigênio Singlete , Animais , Humanos , Oxirredução , Luz , Mamíferos
6.
J Am Chem Soc ; 144(37): 16720-16725, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36094431

RESUMO

Melanin is an organic material biosynthesized from tyrosine in pigment-producing cells. The present study reports a simple method to generate tailored functional materials in mammalian cells by chemically fabricating intracellular melanin. Our approach exploits synthetic tyrosine derivatives to hijack the melanin biosynthesis pathway in pigment-producing cells. Its application was exemplified by synthesizing and using a paramagnetic tyrosine derivative, m-YR, which endowed melanoma cells with responsiveness to external magnetic fields. The mechanical force generated by the magnet-responsive melanin forced the cells to elongate and align parallel to the magnetic power lines. Critically, even non-pigment cells were similarly remote-controlled by external magnetic fields once engineered to express tyrosinase and treated with m-YR, suggesting the versatility of the approach. The present methodology may potentially provide a new avenue for mechanobiology and magnetogenetic studies and a framework for magnetic control of specific cells.


Assuntos
Melaninas , Monofenol Mono-Oxigenase , Animais , Fenômenos Magnéticos , Mamíferos/metabolismo , Melaninas/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Tirosina/metabolismo
7.
ACS Omega ; 7(15): 12637-12642, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35474842

RESUMO

Polymer electrolyte membrane fuel cells have recently attracted considerable attention as sustainable and eco-friendly electricity generation devices from the viewpoint of carbon neutrality. This study focuses on new discoveries related to the application of eggshell membranes to polymer electrolytes in the development of cheaper, more eco-friendly fuel cells. We observed the electricity generation of the fuel cells using an eggshell membrane as a proton-conductive material and a general carbonic acid aqueous solution. This new fuel cell will contribute to the continued improvement of available fuel cells at lower costs.

8.
Sci Rep ; 12(1): 2598, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35173220

RESUMO

This prospective study determined the effects of hypoglycemic stimulation on vascular endothelial function in non-diabetic patients using reactive hyperemia peripheral arterial tonometry (RH-PAT). The study included non-diabetic patients who were hospitalized for an insulin tolerance test (ITT) for the diagnosis of hypoadrenocorticism or hypopituitarism. Vascular endothelial function was assessed using the reactive hyperemia index (RHI) measured by the RH-PAT. We also measured the levels of anterior pituitary hormone, adrenaline, noradrenaline, and dopamine at the time of hypoglycemia. The primary endpoint was a change in the RHI at 120 min after insulin administration. The study included 27 patients. ITT was associated with significant increases in systolic blood pressure, pulse rate, and the blood levels of adrenocorticotropic hormone, cortisol, growth hormone, adrenaline, noradrenaline, and dopamine. RHI significantly decreased after ITT from 2.24 ± 0.51 to 1.71 ± 0.42. A significant inverse correlation was observed between the change in RHI and change in adrenaline (r = - 0.670, p = 0.012). We concluded that hypoglycemic stimulation altered vascular endothelial function, as measured by RH-PAT, even in patients free of glucose intolerance. The observed deterioration in vascular endothelial function correlated with increases in catecholamine levels during hypoglycemia.Trial registration: UMIN000033244.


Assuntos
Endotélio Vascular/fisiopatologia , Hipoglicemia/fisiopatologia , Manometria/métodos , Adulto , Idoso , Artérias , Dopamina/sangue , Epinefrina/sangue , Feminino , Intolerância à Glucose , Teste de Tolerância a Glucose , Humanos , Hiperemia , Hipoglicemia/sangue , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Norepinefrina/sangue , Hormônios Adeno-Hipofisários/sangue , Estudos Prospectivos , Sístole
9.
J UOEH ; 43(1): 97-102, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-33678791

RESUMO

The patient was a 34-year-old woman. Surgical resection and chemotherapy had been performed on diagnosis of malignant melanoma in year X-9. Chronic thyroiditis was diagnosed in year X-8, but her thyroid function was normal. In November of the year X-1, the patient, who had metastasis to the left lung and the left main bronchus and radically unresectable metastases with distant metastases, was treated with the anti-PD-1 antibody nivolumab. In December X-1, we initiated levothyroxine sodium for hypothyroidism after the patient suffered indolent thyroiditis due to nivolumab. In March X, the nivolumab treatment was stopped because it proved to be ineffective, then in April, anorexia, fever, and general malaise were noted. Cortisol 5.0 and ACTH 17.5 were confirmed by blood test, and the patient was diagnosed with adrenal insufficiency and was admitted to the hospital. Head MRI showed no organic lesions, and a stress test showed abnormalities only in a CRH test (low response to both ACTH and cortisol). The patient was diagnosed with isolated ACTH deficiency due to nivolumab. Side effects of thyroid dysfunction due to nivolumab are frequently observed in Japan at a rate of 14.3%, and overseas at 5.9%. However, secondary adrenocortical dysfunction is observed in overseas clinical trials at a frequency of only about 0.3%. There are few reports of such complications, and we report this as a rare case.


Assuntos
Hormônio Adrenocorticotrópico/deficiência , Antineoplásicos Imunológicos/efeitos adversos , Hipotireoidismo/induzido quimicamente , Melanoma/tratamento farmacológico , Nivolumabe/efeitos adversos , Neoplasias Cutâneas/tratamento farmacológico , Adulto , Antineoplásicos Imunológicos/uso terapêutico , Feminino , Humanos , Hidrocortisona/administração & dosagem , Hidrocortisona/uso terapêutico , Hipotireoidismo/tratamento farmacológico , Nivolumabe/uso terapêutico , Resultado do Tratamento
10.
J Diabetes Investig ; 12(2): 290-292, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32603545

RESUMO

Anti-N-methyl-D-aspartate receptor (NMDA-R) encephalitis is an autoimmune disorder in which autoantibodies in the limbic system bind to GluN1 subunits of NMDA-Rs in the brain. We report a rare case of autoimmune polyendocrine syndrome type 3 complicated by anti-NMDA-R encephalitis. After hospitalization for type 1 diabetes, the 39-year-old patient developed various schizophreniform symptoms and seizures after cold-like symptoms. These findings are consistent with the diagnosis of anti-NMDA-R encephalitis. Immune-related encephalitis was suspected at the early phase of the disease, and cerebrospinal fluid was positive for anti-NMDA-R antibody. Early steroid pulse therapy was initiated during the disease course. The condition improved gradually to full recovery. Early detection and treatment of anti-NMDA-R encephalitis should enhance a positive outcome, considering that besides thyroid diseases and type 1 diabetes, various autoimmune diseases are associated with autoimmune polyendocrine syndrome type 3.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato/complicações , Autoanticorpos/imunologia , Poliendocrinopatias Autoimunes/patologia , Adulto , Humanos , Masculino , Poliendocrinopatias Autoimunes/tratamento farmacológico , Poliendocrinopatias Autoimunes/etiologia , Prognóstico
11.
Chembiochem ; 19(9): 979-985, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29665240

RESUMO

The ten-eleven translocation (TET) protein family, consisting of three isoforms (TET1/2/3), have been found in mammalian cells and have a crucial role in 5-methylcytosine demethylation in genomic DNA through the catalysis of oxidation reactions assisted by 2-oxoglutarate (2OG). DNA methylation/demethylation contributes to the regulation of gene expression at the transcriptional level, and recent studies have revealed that TET1 is highly elevated in malignant cells of various diseases and related to malignant alteration. TET1 inhibitors based on a scaffold of thioether macrocyclic peptides, which have been discovered by the random nonstandard peptide integrated discovery (RaPID) system, are reported. The affinity-based selection was performed against the TET1 compact catalytic domain (TET1CCD) to yield thioether macrocyclic peptides. These peptides exhibited inhibitory activity of the TET1 catalytic domain (TET1CD), with an IC50 value as low as 1.1 µm. One of the peptides, TiP1, was also able to inhibit TET1CD over TET2CD with tenfold selectivity, although it was likely to target the 2OG binding site; this provides a good starting point to develop more selective inhibitors.


Assuntos
Metilação de DNA/efeitos dos fármacos , Compostos Macrocíclicos/farmacologia , Oxigenases de Função Mista/antagonistas & inibidores , Peptídeos Cíclicos/farmacologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Sulfetos/farmacologia , Sequência de Aminoácidos , Domínio Catalítico/efeitos dos fármacos , Descoberta de Drogas , Humanos , Compostos Macrocíclicos/química , Oxigenases de Função Mista/química , Oxigenases de Função Mista/metabolismo , Peptídeos Cíclicos/química , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/metabolismo , Sulfetos/química
12.
Yakugaku Zasshi ; 136(2): 191-6, 2016.
Artigo em Japonês | MEDLINE | ID: mdl-26831792

RESUMO

Membrane proteins allow a cell to communicate with its environment by relaying a signal or transporting a molecule through the cell membrane. Elucidation of the three-dimensional structure of a membrane protein provides a greater understanding of its function and mechanisms. Ultimately, this knowledge will enlighten researchers on how these proteins can be regulated to elicit a desired cellular response, which could lead to novel therapeutic medicine. Unfortunately, the determination of the high-resolution crystal structures of transmembrane proteins remains a challenge due to their poor solubility and high conformational flexibility. Additives and cocrystallization ligands are being used to address these problems. In vitro selected macrocyclic peptides have recently been successfully employed as cocrystallization ligands. Although originally intended as inhibitors and drug lead molecules, in vitro selected macrocyclic peptides are now showing that their pharmacodynamic properties also allow them to serve as excellent cocrystallization ligands. Structures for macrocyclic peptide-bound transporters, the multidrug and toxic compound extrusion family transporter from Pyrococcus furiosus (PfMATE) and the ABC transporter subfamily B member 1 from Cyanidioschyzon meraloe (CmABCB1), have been elucidated using X-ray crystallography. The cocrystal structures reveal that the macrocyclic peptides improve crystallization by binding in a similar manner as a small molecule or a biologic. The PfMATE-binding macrocyclic peptides MaD3S and MaD5 bind to the surfaces buried in the center channel of the transporters. Although both transporters possess a center channel and substrate-binding pocket, the CmABCB1-binding macrocyclic peptide, aCAP, binds to the outer surface of the transporter in a similar manner to a biologic.


Assuntos
Proteínas de Membrana Transportadoras/química , Proteínas de Membrana Transportadoras/fisiologia , Complexos Multiproteicos , Peptídeos , Transportadores de Cassetes de Ligação de ATP/química , Transportadores de Cassetes de Ligação de ATP/fisiologia , Comunicação Celular , Membrana Celular/metabolismo , Cristalização , Cristalografia por Raios X , Técnicas In Vitro , Ligantes , Complexos Multiproteicos/química , Complexos Multiproteicos/genética , Complexos Multiproteicos/fisiologia , Peptídeos/química , Peptídeos/genética , Peptídeos/fisiologia , Ligação Proteica , Conformação Proteica , Transdução de Sinais
13.
Colloids Surf B Biointerfaces ; 64(2): 162-9, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-18313904

RESUMO

We developed novel magnetic nano-carriers around 180 nm in diameter for affinity purification. Prepared magnetic nano-carriers possessed uniform core/shell/shell nano-structure composed of 40 nm magnetite particles/poly(styrene-co-glycidyl methacrylate (GMA))/polyGMA, which was constructed by admicellar polymerization. By utilizing relatively large 40 nm magnetite particles with large magnetization, the magnetic nano-carriers could show good response to permanent magnet. Thanks to uniform polymer shell with high physical/chemical stability, the magnetic nano-carriers could disperse in a wide range of organic solvent without disruption of core/shell structure and could immobilize various kinds of drugs. We examined affinity purification using our prepared magnetic nano-carriers with anti-cancer agent methotrexate (MTX) as ligand. Our magnetic nano-carriers showed higher performance compared to commercially available magnetic beads in terms of purification efficiency of target including extent of non-specific binding protein.


Assuntos
Cromatografia de Afinidade , Sistemas de Liberação de Medicamentos , Magnetismo , Nanopartículas/química , Antimetabólitos Antineoplásicos/administração & dosagem , Compostos de Epóxi/química , Compostos Férricos/química , Luz , Metacrilatos/química , Metotrexato/administração & dosagem , Microesferas , Modelos Químicos , Nanopartículas/ultraestrutura , Tamanho da Partícula , Polímeros/química , Espalhamento de Radiação , Estireno/química , Termogravimetria
14.
Colloids Surf B Biointerfaces ; 54(2): 249-53, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17156980

RESUMO

Despite the wide utility of ferrite nanoparticles (FP), a methodology to conjugate heterologous molecules to FP is still limited and characterization of small molecule-conjugated FP is not well known. Here, we describe what kinds of proteins and amino acids are selectively immobilized onto FP when FP is synthesized in the presence of these molecules. Two-dimentional gel electrophoresis (2D SDS-PAGE) showed that proteins with low pI value were selectively bound to FP. Quantitative analyses using HPLC suggested that L-aspartic acid (Asp) and L-cysteine (Cys) were bound to FP selectively among natural amino acids examined. Additional analysis of compounds-conjugated FP revealed that selective binding of Asp to FP was attributed with its molecular structure. It was found that the substructure of amino acid-bound to FP specifically was composed of a defined chelation of two carboxyl groups separated by two carbon atoms as deduced from FT-IR measurement. Thus, we concluded that molecules possessing two carboxyl groups separated by two carbons were bound to FP spontaneously and selectively, which might enable the attachment of free functional groups onto the FP surface if their molecules have functional groups other than carboxyl groups. The resulting complex might be applicable as a chemical tag to immobilize various molecules onto FP.


Assuntos
Compostos Férricos , Nanopartículas , Adsorção , Ácido Aspártico/farmacocinética , Células HeLa , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier
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