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1.
Small Methods ; 8(1): e2301158, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37821419

RESUMO

Alloying-type metallic tin is perceived as a potential anode material for K-ion batteries owing to its high theoretical capacity and reasonable working potential. However, pure Sn still face intractable issues of inferior K+ storage capability owing to the mechanical degradation of electrode against large volume changes and formation of intermediary insulating phases K4 Sn9 and KSn during alloying reaction. Herein, the TiC/C-carbon nanotubes (CNTs) is prepared as an effective buffer matrix and composited with Sn particles (Sn-TiC/C-CNTs) through the high-energy ball-milling method. Owing to the conductive and rigid properties, the TiC/C-CNTs matrix enhances the electrical conductivity as well as mechanical integrity of Sn in the composite material and thus ultimately contributes to performance supremacy in terms of electrochemical K+ storage properties. During potassiation process, the TiC/C-CNTs matrix not only dissipates the internal stress toward random radial orientations within the Sn particle but also provides electrical pathways for the intermediate insulating phases; this tends to reduce microcracking and prevent considerable electrode degradation.

2.
Adv Mater ; 35(32): e2209673, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37043776

RESUMO

In the last decade, soft acoustic/vibration sensors have gained tremendous research interest due to their unique ability to detect broadband acoustic/vibration stimuli, potentializing futuristic applications including voice biometrics, voice-controlled human-machine-interfaces, electronic skin, and skin-mountable healthcare devices. Importantly, to benefit most from these sensors, it is inevitable to use machine learning (ML) to process their output signals; with ML, a more accurate and efficient interpretation of original data is possible. This paper is dedicated to offering an overview of recent advances empowering the development of soft acoustic/vibration sensors and their signal processing using ML. First, the key performance parameters of the sensors are discussed. Second, popular transduction mechanisms for the sensors are addressed, followed by an in-depth overview of each type, covering materials used, structural designs, and sensing performances. Third, potential applications of the sensors are elaborated and fourth, a thorough discussion on ML is conducted, exploring different types of ML, specific ML algorithms suitable for processing acoustic/vibration signals, and current trends in ML-assisted applications. Finally, the challenges and potential opportunities in soft acoustic/vibration sensor and ML research are revealed to offer new insights into future prospects in these fields.

3.
Opt Express ; 30(23): 42406-42414, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36366695

RESUMO

We demonstrated that a well-designed nanopatterned cover improves photovoltaic efficiency across a wide range of incident angles (θ). A nanopatterned cover was created using an integrated ray-wave optics simulation to maximize the light absorption of the surface-textured Si photovoltaic device. A hexagonally arranged nanocone array with a 300 nm pitch was formed into a polymer using nanoimprinting, and the nanostructured polymer was then attached to a glass cover with an index-matching adhesive. Angle-resolved current density-voltage measurements on Si photovoltaic devices showed that the nanopatterned glass cover yielded a 2-13% enhancement in power conversion efficiency at θ = 0-60°, which accounted for its broadband antireflective feature. We performed all-season-perspective simulations based on the results of the integrated ray-wave optics simulations and solar altitude database of South Korea, which validated the sustainability of the developed nanopatterned cover during significant seasonal fluctuations.

4.
Food Sci Nutr ; 10(7): 2381-2389, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35844922

RESUMO

Caesalpinia eriostachys Benth. (CE) is native to the Mexico and multiple effects have been observed from several plants belonging to the same family. CE was subjected to extraction with 95% ethanol, and the components were isolated through column chromatography. The structure of the compound was elucidated based on nuclear magnetic resonance (NMR) spectral data, electron ionization-mass (EI-MS) spectroscopy, and liquid chromatography-mass (LC-MS) spectroscopy. In vivo antinociceptive studies were conducted using writhing, 5% formalin, tail-flick, hot-plate, and von Frey filament tests. The ethanolic extract showed a significant effect in the acetic acid-induced pain model and nociceptive behavior in the formalin model (second phase). In hot-plate test and tail-flick test, the results showed no difference compared to the control group. The results suggest that the ethanolic extract may act peripherally to reduce pain. In the streptozotocin (STZ)-induced pain model, the ethanolic extract showed significant effect in the von Frey test model. The n-Hex (Hexane) and MC (Methylene chloride) fractions and isolated compounds, ellagic acid and agathisflavone, showed increased effect. Based on these results, we confirmed that the CE ethanolic extract and their compounds, ellagic acid and agathisflavone, have antinociceptive effect on diabetes mellitus-induced pain. Furthermore, the results of this study might be valuable for identifying compounds with antinociceptive activity from natural products.

5.
J Cosmet Dermatol ; 21(7): 3117-3126, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34841665

RESUMO

INTRODUCTION: This study investigated the role of natural polymers as moisturizers with low toxicity and biodegradability in the cosmetic and pharmaceutical industries. We isolated a polysaccharide extract from Dendrobium candidum (D. candidum) and determined its efficacy in skin hydration when used as an active cosmetic ingredient. METHODS: The molecular weight distribution of D. candidum polysaccharides was analyzed via gel permeation chromatography (GPC). We performed real-time reverse transcription PCR (RT-PCR) and western blotting assays to investigate the physiological mechanism of the polysaccharides extracted from D. candidum (PDC). Based on in vitro data, the efficacy of PDC in improving skin condition was tested on the face of 21 volunteers. RESULTS: The expression of filaggrin (FLG), caspase-14, and bleomycin hydrolase, which are the major components contributing to skin hydration, was significantly increased in the PDC-treated group. Further, the PDC upregulated the mRNA expression of occludin and claudin-1, which play a key role in epidermal barrier function. In addition, a topical application of PDC markedly increased skin hydration and improved trans-epidermal water loss (TEWL) and skin elasticity after 2 weeks. CONCLUSIONS: It is the first study reporting the efficacy of PDC-mediated FLG mechanism associated with positive skin hydration. PDC can be used as an active ingredient in moisturizers. Long-term application of PDC-based moisturizers may result in significant improvement in elasticity and barrier function.


Assuntos
Dendrobium , Dendrobium/química , Epiderme/metabolismo , Humanos , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia , Pele
6.
Plants (Basel) ; 10(12)2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34961244

RESUMO

We previously reported that Lepechinia meyenii (Walp.) Epling has antioxidant and aldose reductase (AR) inhibitory activities. In this study, L. meyenii was extracted in a 50% MeOH and CH2Cl2/MeOH system. The active extracts of MeOH and 50% MeOH were subjected to fractionation, followed by separation using high-speed counter-current chromatography (HSCCC) and preparative HPLC. Separation and identification revealed the presence of caffeic acid, hesperidin, rosmarinic acid, diosmin, methyl rosmarinate, diosmetin, and butyl rosmarinate. Of these, rosmarinic acid, methyl rosmarinate, and butyl rosmarinate possessed remarkable antioxidant and AR inhibitory activities. The other compounds were less active. In particular, rosmarinic acid is the key contributor to the antioxidant and AR inhibitory activities of L. meyenii; it is rich in the MeOH extract (333.84 mg/g) and 50% MeOH extract (135.41 mg/g) of L. meyenii and is especially abundant in the EtOAc and n-BuOH fractions (373.71-804.07 mg/g) of the MeOH and 50% MeOH extracts. The results clarified the basis of antioxidant and AR inhibitory activity of L. meyenii, adding scientific evidence supporting its traditional use as an anti-diabetic herbal medicine. The HSCCC separation method established in this study can be used for the preparative separation of rosmarinic acid from natural products.

7.
Chem Commun (Camb) ; 57(71): 8929-8932, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34397047

RESUMO

A cyclocyanine (CC)-based organic small molecule two-photon (TP) fluorescent probe (CCNa1) was developed for mitochondrial sodium ion sensing. CCNa1 exhibits a low solvatochromic shift and strong TP fluorescence enhancement at 575 nm upon binding to Na+ and is insensitive to other metal ions and to pH. CCNa1 demonstrated fast cell loading ability, biocompatibility, and sensitive response to mitochondrial Na+ influx in live cells and mouse brain tissue.


Assuntos
Corantes Fluorescentes/química , Mitocôndrias/química , Sódio/análise , Animais , Éteres de Coroa/química , Éteres de Coroa/efeitos da radiação , Éteres de Coroa/toxicidade , Corantes Fluorescentes/efeitos da radiação , Corantes Fluorescentes/toxicidade , Células HeLa , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/efeitos da radiação , Compostos Heterocíclicos de 4 ou mais Anéis/toxicidade , Hipocampo/metabolismo , Humanos , Camundongos , Fótons , Sódio/metabolismo
8.
Foods ; 10(5)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068163

RESUMO

Valeriana rigida Ruiz & Pav. (V. rigida) has long been used as a herbal medicine in Peru; however, its phytochemicals and pharmacology need to be scientifically explored. In this study, we combined the offline 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH)-/ultrafiltration-high-performance liquid chromatography (HPLC) and high-speed counter-current chromatography (HSCCC)/pH-zone-refining counter-current chromatography (pH-zone-refining CCC) to screen and separate the antioxidants and aldose reductase (AR) inhibitors from the 70% MeOH extract of V. rigida, which exhibited remarkable antioxidant and AR inhibitory activities. Seven compounds were initially screened as target compounds exhibiting dual antioxidant and AR inhibitory activities using DPPH-/ultrafiltration-HPLC, which guided the subsequent pH-zone-refining CCC and HSCCC separations of these target compounds, namely 3-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, 5-O-caffeoylquinic acid, 3,4-O-di-caffeoylquinic acid, 3,5-O-di-caffeoylquinic acid, 4,5-O-di-caffeoylquinic acid, and 3,4,5-O-tri-caffeoylquinic acid. These compounds are identified for the first time in V. rigida and exhibited remarkable antioxidant and AR inhibitory activities. The results demonstrate that the method established in this study can be used to efficiently screen and separate the antioxidants and AR inhibitors from natural products and, particularly, the root extract of V. rigida is a new source of caffeoylquinic acids with antioxidant and AR inhibitory activities, and it can be used as a potential functional food ingredient for diabetes.

9.
Molecules ; 26(6)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804199

RESUMO

Neuropathic pain is described as the "most terrible of all tortures that a nerve wound may inflict." The aim of the present study was to demonstrate the antinociceptive effect of Symplocos chinensis f. pilosa Ohwi water extract (SCW) and synthesized derivatives of the isolated compound. The antinociceptive effect was tested using the acetic acid-induced writhing and 5% formalin tests. Antinociceptive effects on neuropathic pain were evaluated using the von Frey test with chronic constriction injury (CCI) and surgical nerve injury (SNI) models and tail-flick test with a vincristine-induced pain model. An Ames test was also conducted. 5-hydroxymethylfurfural (5-HMF) was isolated and derivatives were synthesized with various acid groups. Among the plant water extracts, SCW showed significantly effective activity. Additionally, SCW presented antinociceptive effects in the neuropathic pain models. The SCW water fraction resulted in fewer writhes than the other fractions, and isolated 5-HMF was identified as an effective compound. Because 5-HMF revealed a positive response in the Ames test, derivatives were synthesized. Among the synthesized derivations, 5-succinoxymethylfurfural (5-SMF) showed the best effect in the neuropathic pain model. Our data suggest that SCW and the synthesized compound, 5-SMF, possess effective antinociceptive activity against neuropathic pain.


Assuntos
Ericales/química , Neuralgia/tratamento farmacológico , Extratos Vegetais/farmacologia , Analgésicos/farmacologia , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nervo Isquiático/efeitos dos fármacos
10.
ACS Appl Bio Mater ; 4(3): 2135-2141, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35014342

RESUMO

Stomach cancer is a global health issue because of its incidence and mortality rates worldwide. We developed a near-infrared (NIR) emissive ratiometric two-photon (TP) probe (HCC1) for the quantitative analysis of pH in live cells and human stomach tissues. The probe design is based on a restrained hemicyanine core that controls the intramolecular charge transfer from 2-naphthol, with a suitable pKa value (7.50) under physiological conditions. The probe exhibited improved quantum yield, stability, and TP activity under physiological conditions. In addition, intracellular pH titration (pH 4.0 to 10.0) of HCC1 revealed an ideal intracellular pKa of approximately 7.2, negligible cytotoxicity, and TP excited fluorescence in situ, thereby allowing direct imaging of the cellular pH in live cells and tissues. Ratiometric two-photon microscope imaging with HCC1 of human stomach tissue revealed a clear intratissue pH variation among normal, adenoma, and cancer tissues. Our results demonstrate that HCC1 is useful as an NIR imaging probe for in situ pH-related studies and in cancer research.


Assuntos
Materiais Biocompatíveis/química , Corantes Fluorescentes/química , Fótons , Neoplasias Gástricas/diagnóstico por imagem , Linhagem Celular Tumoral , Humanos , Concentração de Íons de Hidrogênio , Teste de Materiais , Estrutura Molecular , Tamanho da Partícula , Neoplasias Gástricas/patologia
11.
J Phys Chem Lett ; 11(17): 7103-7108, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32787320

RESUMO

Cryogenic ion spectroscopy (CIS) was applied to singly protonated DYYVVR, a tryptic peptide that contains the two active tyrosine residues (Y980 and Y981) of the Janus kinase 3 (JAK3) kinase domain, together with its point mutants (Y980F and Y981F) and phosphorylated peptides (pY980, pY981, and pY980pY981). The two tyrosine chromophores showed distinguishable UV absorption bands at around 35 200 and 35 450 cm-1, respectively. By comparing with the point mutants, the lower electronic band was assigned to the absorption of Y981, and the higher one was assigned to Y980. When phosphorylated, the UV absorption of the phosphorylated chromophore shifts to higher energy above 36 500 cm-1 but the unphosphorylated chromophore gives the absorption in the same region. Conformer-specific IR spectroscopy and density functional theory (DFT) calculations were used to tentatively assign the structure of DYYVVR. Two conformations were found, where Y981 is solvated by the protonated side chain of arginine R984, and the orientation of the carboxylic OH of D979 was different between the two. It is demonstrated that CIS can be used to distinguish the two tyrosine chromophores and to locate the phosphorylation site of a kinase domain.


Assuntos
Oligopeptídeos/química , Proteínas Quinases/química , Prótons , Análise Espectral , Sequência de Aminoácidos , Sítios de Ligação , Modelos Moleculares , Oligopeptídeos/metabolismo , Fosforilação , Domínios Proteicos
12.
Biomol Ther (Seoul) ; 28(5): 397-404, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32576717

RESUMO

Adiponectin secretion-promoting compounds have therapeutic potentials in human metabolic diseases. Diallyl biphenyl-type neolignan compounds, magnolol, honokiol, and 4-O-methylhonokiol, from a Magnolia officinalis extract were screened as adiponectin- secretion promoting compounds in the adipogenic differentiation model of human bone marrow mesenchymal stem cells (hBM-MSCs). In a target identification study, magnolol, honokiol, and 4-O-methylhonokiol were elucidated as PPARα and PPARγ dual modulators. Diallyl biphenyl-type neolignans affected the transcription of lipid metabolism-associated genes in a different way compared to those of specific PPAR ligands. The diallyl biphenyl-type neolignan structure provides a novel pharmacophore of PPARα/γ dual modulators, which may have unique therapeutic potentials in diverse metabolic diseases.

13.
J Ginseng Res ; 44(1): 115-122, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32148394

RESUMO

BACKGROUND: In aged skin, degradation of collagen fibers, which occupy the majority of the extracellular matrix in the dermis, and changes of aquaporin 3 (AQP3) and skin constituents, such as hyaluronic acid and ceramide, cause wrinkles and decrease skin moisturization to contribute to dryness and lower elasticity skin. Red ginseng (RG) is used as a cosmetic and food material and is known to protect from UVB-induced cell death, increase skin hydration, prevent wrinkles, and have an antioxidative effect. But, in general, RG used as a material is the soluble liquid portion in the solvent, and the part that is not soluble in the solvent is discarded. Thus, we made the whole RG into microgranulation and dispersed in water to produce gel form for using entire RG, and it was named red ginseng NaturalGEL (RG NGEL). METHODS: RG NGEL was investigated for matrix metalloproteinases inhibitory activity, induction of Type I collagen, AQP3, hyaluronan synthetase 2, serine palmitoyl transferase, ceramide synthase 3, and filaggrin expression and compared with RG water extract. RESULTS: RG NGEL reduced the levels of UV-induced matrix metalloproteinases and increased Type I collagen in human fibroblast cells and upregulated AQP3, hyaluronan synthetase 2, serine palmitoyl transferase, ceramide synthase 3, and filaggrin expressions in human keratinocytes compared with RG water extract. CONCLUSION: RG NGEL has the potential as an effective reagent for antiaging cosmetics to improve wrinkle formation and skin hydration.

14.
Chem Sci ; 12(1): 427-434, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-34163605

RESUMO

Two-photon photodynamic therapy (TP-PDT) is a promising approach for the treatment of cancer because of its better penetration depth and superior spatial selectivity. Here, we describe an azo group containing cyclized-cyanine derivatives (ACC1 and ACC2) as a two-photon activated, type I based photosensitizer (PS). These small-molecule and heavy atom-free organic dyes showed marked reactive oxygen species (ROS)-generating ability under physiological conditions, as well as fast loading ability into the cells and negligible dark toxicity. Live cell analyses with one- and two-photon microscopy revealed that these dyes showed higher ROS generation ability upon two-photon excitation than upon one-photon excitation via the type I process. The PSs have superior PDT properties compared to conventional Visudyne and 5-ALA under mild conditions. These characteristics allowed for precise PDT at the target region in mimic tumor spheroids, demonstrating that the developed TP PS could be useful in efficient PDT applications and in designing various PSs.

15.
Materials (Basel) ; 12(11)2019 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-31159501

RESUMO

The aim of this work was to study the mechanical strength and microstructure changes of alkali-activated slag mortar (AAS mortar) after being heat treated in the temperature range of 200-1000 °C. The AAS mortar was cured in the ambient condition (20 ± 5 °C, 60 ± 5% RH) (Relative humidity: RH) and high temperature condition (80 °C) for 27 days with three different heating regimes: curing in a dry oven, curing in sealed plastic bags, and in a steam environment. The activator for the AAS synthesis was a mixture of sodium silicate solution (water glass) and sodium hydroxide (NaOH) with a SiO2/Na2O weight ratio of 1, and a dosage of 4% Na2O by slag weight. Thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) incorporated with energy-dispersive X-ray spectroscopy (EDX) were used to assess the mortar microstructure change. The results revealed that the curing method significantly affected the mechanical strength of AAS at temperatures lower than 800 °C. The heat treatment at late age of 28 days was more beneficial for compressive strength enhancement in specimens without using heat curing methods.

16.
Anal Chem ; 90(21): 12937-12943, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30303000

RESUMO

The naphthoimidazolium borane 4 is shown to be a selective probe for HOCl over other reactive oxygen species. Unlike other boronate-reactive oxygen species (ROS) fluorogenic probes that are oxidized by HOCl through a nucleophilic borono-Dakin oxidation mechanism, probe 4 is distinguished by its electrophilic oxidation mechanism involving B-H bond cleavage. Two-photon microscopy experiments in living cells and tissues with the probe 4 demonstrate the monitoring of endogenous HOCl generation and changes in HOCl concentrations generated in the endoplasmic reticulum during oxidative stress situations.


Assuntos
Boranos/química , Retículo Endoplasmático/metabolismo , Corantes Fluorescentes/química , Ácido Hipocloroso/análise , Imidazóis/química , Animais , Boranos/síntese química , Boranos/efeitos da radiação , Linhagem Celular Tumoral , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/efeitos da radiação , Humanos , Hidrólise , Ácido Hipocloroso/metabolismo , Imidazóis/síntese química , Imidazóis/efeitos da radiação , Masculino , Camundongos , Microscopia/métodos , Oxirredução , Células RAW 264.7 , Ratos Sprague-Dawley , Raios Ultravioleta
17.
Phys Chem Chem Phys ; 20(30): 19979-19986, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30022200

RESUMO

UV-UV hole burning and IR dip spectra of l-ß3-homotryptophan were measured by a laser desorption supersonic jet technique as a bottom-up approach to understand the secondary structures of ß-peptides. 14 conformers were found by UV-UV hole burning spectroscopy. The conformers were classified into three groups depending on their hydrogen bonding patterns observed in their conformer-specific IR spectra, and tentatively assigned by comparing with quantum chemical calculations. Group 1 had free OH stretch but no NH2 anti-symmetric stretch vibrational transition and was assigned to NH-π hydrogen bonded structures. Group 2, including the most abundant conformer, showed both free OH and NH2 anti-symmetric stretch vibrations, and belonged to NH-O hydrogen bonded conformations. Group 3 of conformers had hydrogen-bonded OH stretch IR transition and had OH-N hydrogen bonds. The internal hydrogen bond of group 3 is a C6 hydrogen bond due to the additional carbon atom at the ß position and shows a shorter bond length than that of a C5 hydrogen bond. While the OH-N C6 hydrogen bond is stronger than NH-O, the entropic effect prefers the more flexible NH-O hydrogen bonded structure. It is expected that the unnatural C6 hydrogen bond influences the conformations of ß-peptides and builds totally different secondary structures than those of α-peptides.


Assuntos
Triptofano/análogos & derivados , Triptofano/química , Entropia , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Teoria Quântica , Espectrofotometria Infravermelho/métodos
18.
J Cell Mol Med ; 22(9): 4117-4129, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29851245

RESUMO

Phosphatidylinositol 4-phosphate 5-kinase (PIP5K) family members generate phosphatidylinositol 4,5-bisphosphate (PIP2), a critical lipid regulator of diverse physiological processes. The PIP5K-dependent PIP2 generation can also act upstream of the oncogenic phosphatidylinositol 3-kinase (PI3K)/Akt pathway. Many studies have demonstrated various mechanisms of spatiotemporal regulation of PIP5K catalytic activity. However, there are few studies on regulation of PIP5K protein stability. Here, we examined potential regulation of PIP5Kα, a PIP5K isoform, via ubiquitin-proteasome system, and its implication for breast cancer. Our results showed that the ubiquitin ligase NEDD4 (neural precursor cell expressed, developmentally down-regulated gene 4) mediated ubiquitination and proteasomal degradation of PIP5Kα, consequently reducing plasma membrane PIP2 level. NEDD4 interacted with the C-terminal region and ubiquitinated the N-terminal lysine 88 in PIP5Kα. In addition, PIP5Kα gene disruption inhibited epidermal growth factor (EGF)-induced Akt activation and caused significant proliferation defect in breast cancer cells. Notably, PIP5Kα K88R mutant that was resistant to NEDD4-mediated ubiquitination and degradation showed more potentiating effects on Akt activation by EGF and cell proliferation than wild-type PIP5Kα. Collectively, these results suggest that PIP5Kα is a novel degradative substrate of NEDD4 and that the PIP5Kα-dependent PIP2 pool contributing to breast cancer cell proliferation through PI3K/Akt activation is negatively controlled by NEDD4.


Assuntos
Membrana Celular/metabolismo , Regulação Neoplásica da Expressão Gênica , Ubiquitina-Proteína Ligases Nedd4/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Membrana Celular/química , Membrana Celular/efeitos dos fármacos , Proliferação de Células , Fator de Crescimento Epidérmico/farmacologia , Feminino , Edição de Genes , Humanos , Mutação , Ubiquitina-Proteína Ligases Nedd4/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 4,5-Difosfato/metabolismo , Fosforilação/efeitos dos fármacos , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais , Ubiquitinação/efeitos dos fármacos
19.
Appl Radiat Isot ; 115: 8-12, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27295512

RESUMO

A separation study using a (176)Yb target for the preparation of nca (177)Lu, which is a beta-emitting nuclide used not only in radioimmunotherapy applications but also in the treatment of various lesions, has been performed. A material having a better selectivity and separation efficiency for Lu than Yb was developed, and the separation conditions of (177)Lu were derived using this from a neutron irradiated (176)Yb target. The separation material was an organo-ceramic hybrid material containing a phosphate group. Adsorption behavior was determined through batch experiments, and (177)Lu separation from the Yb target was evaluated through column experiments. The Yb target, with a 99.72% in (176)Yb, was irradiated in the irradiation hole of HANARO, which has a thermal neutron flux of 1.6E+14ncm(-2)s(-1). The batch experiments revealed that the organo-ceramic hybrid material (Sol-POS) had a separation factor of 1.6 at 0.5M HCl. Separation was performed through extraction chromatography using a 5mg enriched Yb target, and the separation yield of the NCA (177)Lu was about 78%. If the amount of Yb target is increased to produce curies level (177)Lu, additional purification will be needed.


Assuntos
Lutécio/isolamento & purificação , Radioisótopos/isolamento & purificação , Compostos Radiofarmacêuticos/isolamento & purificação , Adsorção , Quelantes , Cromatografia/métodos , Humanos , Lutécio/uso terapêutico , Nêutrons , Radioisótopos/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico , República da Coreia , Tecnologia Radiológica/instrumentação , Tecnologia Radiológica/métodos , Itérbio/efeitos da radiação
20.
Phys Chem Chem Phys ; 18(16): 11306-22, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27054830

RESUMO

The conformational preferences of a series of short, aromatic-capped, glutamine-containing peptides have been studied under jet-cooled conditions in the gas phase. This work seeks a bottom-up understanding of the role played by glutamine residues in directing peptide structures that lead to neurodegenerative diseases. Resonant ion-dip infrared (RIDIR) spectroscopy is used to record single-conformation infrared spectra in the NH stretch, amide I and amide II regions. Comparison of the experimental spectra with the predictions of calculations carried out at the DFT M05-2X/6-31+G(d) level of theory lead to firm assignments for the H-bonding architectures of a total of eight conformers of four molecules, including three in Z-Gln-OH, one in Z-Gln-NHMe, three in Ac-Gln-NHBn, and one in Ac-Ala-Gln-NHBn. The Gln side chain engages actively in forming H-bonds with nearest-neighbor amide groups, forming C8 H-bonds to the C-terminal side, C9 H-bonds to the N-terminal side, and an amide-stacked geometry, all with an extended (C5) peptide backbone about the Gln residue. The Gln side chain also stabilizes an inverse γ-turn in the peptide backbone by forming a pair of H-bonds that bridge the γ-turn and stabilize it. Finally, the entire conformer population of Ac-Ala-Gln-NHBn is funneled into a single structure that incorporates the peptide backbone in a type I ß-turn, stabilized by the Gln side chain forming a C7 H-bond to the central amide group in the ß-turn not otherwise involved in a hydrogen bond. This ß-turn backbone structure is nearly identical to that observed in a series of X-(AQ)-Y ß-turns in the protein data bank, demonstrating that the gas-phase structure is robust to perturbations imposed by the crystalline protein environment.


Assuntos
Glutamina/química , Peptídeos/química , Conformação Proteica , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
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