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1.
Small ; 20(13): e2307694, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37967333

RESUMO

Although adoptive cell-based therapy is illuminated as one of the promising approaches in cancer immunotherapy, it shows low antitumor efficacy because transferred cells adapt and alter toward a pro-tumoral phenotype in response to the tumor's immunosuppressive milieu. Herein, nanoengineered macrophages anchored with functional liposome armed with cholesterol-conjugated Toll-like receptor 7/8 agonist (masked TLR7/8a, m7/8a) are generated to overcome the shortcomings of current macrophage-based therapies and enhance the remodeling of the immunosuppressive tumor microenvironment (TME). The liposome-anchored macrophages (LAMΦ-m7/8a), are fabricated by anchoring dibenzocyclooctyne-modified liposome(m7/8a) onto azido-expressing macrophages via a bio-orthogonal click reaction, are continuously invigorated due to the slow internalization of liposome(m7/8a) and sustained activation. LAMΦ-m7/8a secreted ≈3 and 33-fold more IL-6 and TNF-α than conventional M1-MΦ, maintained the M1 phenotype, and phagocytosed tumor cells for up to 48 h in vitro. Both intratumoral and intravenous injections of LAMΦ-m7/8a induced effective antitumor efficacy when treated in combination with doxorubicin-loaded liposomes in 4T1-tumor bearing mice. It not only increases the infiltration of antigen-specific CD8+ T cells secreting granzyme B, IFN-γ, and TNF-α within the TME, but also reduces myeloid-derived suppressor cells. These results suggest that LAMΦ-m7/8a may provide a suitable alternative to next-generation cell-based therapy platform.


Assuntos
Neoplasias , Receptor 7 Toll-Like , Camundongos , Animais , Linfócitos T CD8-Positivos , Fator de Necrose Tumoral alfa , Lipossomos , Microambiente Tumoral , Macrófagos , Neoplasias/terapia , Imunoterapia/métodos , Adjuvantes Imunológicos , Linhagem Celular Tumoral
2.
Nano Lett ; 23(15): 6859-6867, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37470721

RESUMO

Nanomaterials hybridized with biological components have widespread applications. among many candidates, peptides are attractive in that their peptide sequences can self-assemble with the surface of target materials with high specificity without perturbing the intrinsic properties of nanomaterials. Here, a 1D hybrid nanomaterial was developed through self-assembly of a designed peptide. A hexagonal coiled-coil motif geometrically matched to the diameter of the inorganic nanomaterial was fabricated, whose hydrophobic surface was wrapped along the axis of the hydrophobic core of the coiled coil. Our morphological and spectroscopic analyses revealed rod-shaped, homogeneous peptide-inorganic nanomaterial complexes. Culturing embryonic stem cells on surfaces coated with this peptide-assembled single-chain atomic crystal increased the growth and adhesion of the embryonic stem cells. The hybridized nanomaterial also served as an ECM for brain organoids, accelerating the maturation of neurons. New methods to fabricate hybrid materials through peptide assembly can be applied.


Assuntos
Peptídeos , Células-Tronco Pluripotentes , Peptídeos/farmacologia , Peptídeos/química , Sequência de Aminoácidos , Neurônios , Diferenciação Celular
3.
J Am Chem Soc ; 145(29): 16238-16248, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37462685

RESUMO

Controlling regio- and enantioselectivity in C-H functionalization reactions is of paramount importance due to their versatile synthetic utilities. Herein, we describe a new approach for the asymmetric δ-C(sp3)-H amidation catalysis of dioxazolones using a Cu(I) precursor with a chiral bisoxazoline ligand to access six-membered lactams with high to excellent regio- and enantioselectivity (up to >19:1 rr and >99:1 er). Combined experimental and computational mechanistic studies unveiled that the open-shell character of the postulated Cu-nitrenoids enables the regioselective hydrogen atom abstraction and subsequent enantio-determining radical rebound of the resulting carbon radical intermediates. The synthetic utility of this asymmetric cyclization was demonstrated in the diastereoselective introduction of additional functional groups into the chiral δ-lactam skeleton as well as in the rapid access to biorelevant azacyclic compounds.

4.
Sensors (Basel) ; 23(10)2023 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-37430855

RESUMO

In this study, we introduce a novel design for a three-dimensional (3D) controller, which incorporates the omni-purpose stretchable strain sensor (OPSS sensor). This sensor exhibits both remarkable sensitivity, with a gauge factor of approximately 30, and an extensive working range, accommodating strain up to 150%, thereby enabling accurate 3D motion sensing. The 3D controller is structured such that its triaxial motion can be discerned independently along the X, Y, and Z axes by quantifying the deformation of the controller through multiple OPSS sensors affixed to its surface. To ensure precise and real-time 3D motion sensing, a machine learning-based data analysis technique was implemented for the effective interpretation of the multiple sensor signals. The outcomes reveal that the resistance-based sensors successfully and accurately track the 3D controller's motion. We believe that this innovative design holds the potential to augment the performance of 3D motion sensing devices across a diverse range of applications, encompassing gaming, virtual reality, and robotics.

5.
Molecules ; 28(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36985774

RESUMO

Silver nanoparticles (Ag-NPs) are most effective against pathogens and have widely been studied as antibacterial agents in commodity clothing, medical textile, and other hygiene products. However, prolonged utilization of silver and rapid mutation in bacterium stains has made them resistant to conventional silver agents. On the other hand, strict compliance against excessive utilization of toxic reagents and the current sustainability drive is forcing material synthesis toward green routes with extended functionality. In this study, we proposed an unprecedented chemical-free green synthesis of bioactive Ag-NPs without the incorporation of any chemicals. Cinnamon essential oil (ECO) was used as a bio-reducing agent with and without the mediation of lime extract. A rapid reaction completion with better shape and size control was observed in the vicinity of lime extract when incorporated into the reaction medium. The interaction of natural metabolites and citrus compounds with nanoparticles was established using Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. The application of as-prepared nanoparticles on textiles encompasses extended bioactivity to treated fabric with infused easy-care performance. To the best of our knowledge, this is the first reported instance of utilizing bioactive silver nanoparticles as a functional finish, both as an antimicrobial and as for easy care in the absolute absence of toxic chemicals. The easy-care performance of fabric treated with lime-mediated nanoparticles was found to be 141O, which is around 26% better than bare cotton without any significant loss in fabric strength. Furthermore, to enlighten the sustainability of the process, the development traits were mapped with the United Nations Sustainable Development Goals (SDGs), which show significant influence on SDGs 3, 8, 9, and 14. With the effective suspension of microorganisms, added functionality, and eco-mapping with SDGs with the chemical-free synthesis of nanoparticles, widespread utilization can be found in various healthcare and hygiene products along with the fulfillment of sustainability needs.


Assuntos
Nanopartículas Metálicas , Nanosferas , Prata/farmacologia , Prata/química , Desenvolvimento Sustentável , Nanopartículas Metálicas/química , Antibacterianos/química , Vestuário , Espectroscopia de Infravermelho com Transformada de Fourier , Extratos Vegetais/farmacologia , Extratos Vegetais/química
6.
Sensors (Basel) ; 23(1)2022 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-36616773

RESUMO

Abdominal aortic aneurysm (AAA) is a fatal clinical condition with high mortality. Computed tomography angiography (CTA) imaging is the preferred minimally invasive modality for the long-term postoperative observation of AAA. Accurate segmentation of the thrombus region of interest (ROI) in a postoperative CTA image volume is essential for quantitative assessment and rapid clinical decision making by clinicians. Few investigators have proposed the adoption of convolutional neural networks (CNN). Although these methods demonstrated the potential of CNN architectures by automating the thrombus ROI segmentation, the segmentation performance can be further improved. The existing methods performed the segmentation process independently per 2D image and were incapable of using adjacent images, which could be useful for the robust segmentation of thrombus ROIs. In this work, we propose a thrombus ROI segmentation method to utilize not only the spatial features of a target image, but also the volumetric coherence available from adjacent images. We newly adopted a recurrent neural network, bi-directional convolutional long short-term memory (Bi-CLSTM) architecture, which can learn coherence between a sequence of data. This coherence learning capability can be useful for challenging situations, for example, when the target image exhibits inherent postoperative artifacts and noises, the inclusion of adjacent images would facilitate learning more robust features for thrombus ROI segmentation. We demonstrate the segmentation capability of our Bi-CLSTM-based method with a comparison of the existing 2D-based thrombus ROI segmentation counterpart as well as other established 2D- and 3D-based alternatives. Our comparison is based on a large-scale clinical dataset of 60 patient studies (i.e., 60 CTA image volumes). The results suggest the superior segmentation performance of our Bi-CLSTM-based method by achieving the highest scores of the evaluation metrics, e.g., our Bi-CLSTM results were 0.0331 higher on total overlap and 0.0331 lower on false negative when compared to 2D U-net++ as the second-best.


Assuntos
Angiografia por Tomografia Computadorizada , Trombose , Humanos , Angiografia por Tomografia Computadorizada/métodos , Memória de Curto Prazo , Tomografia Computadorizada por Raios X , Redes Neurais de Computação , Trombose/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos
7.
J Radiol Prot ; 42(3)2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35921807

RESUMO

In line with the activities of Task Group 103 under the International Commission on Radiological Protection (ICRP), the present study was conducted to develop a new set of alimentary tract organs consisting of the oral cavity, oesophagus, stomach, small intestine, and colon for the newborn, 1 year-old, 5 year-old, 10 year-old, and 15 year-old males and females for use in the pediatric mesh-type reference computational phantoms (MRCPs). The developed alimentary tract organs of the pediatric MRCPs, while nearly preserving the original topology and shape of those of the pediatric voxel-type reference computational phantoms (VRCPs) of ICRPPublication 143, present considerable anatomical improvement and include all micrometre-scale target and source regions as prescribed in ICRPPublication 100. To investigate the dosimetric impact of the developed alimentary tract organs, organ doses and specific absorbed fractions were computed for certain external exposures to photons and electrons and internal exposures to electrons, respectively, which were then compared with the values computed using the current ICRP models (i.e. pediatric VRCPs and ICRP-100 stylised models). The results showed that for external exposures to penetrating radiations (i.e. photons >0.04 MeV), there was generally good agreement between the compared values, within a 10% difference, except for the oral mucosa. For external exposures to weakly penetrating radiations (i.e. low-energy photons and electrons), there were significant differences, up to a factor of ∼8300, owing to the geometric difference caused by the anatomical enhancement in the MRCPs. For internal exposures of electrons, there were significant differences, the maximum of which reached a factor of ∼73 000. This was attributed not only to the geometric difference but also to the target mass difference caused by the different luminal content mass and organ shape.


Assuntos
Proteção Radiológica , Telas Cirúrgicas , Criança , Pré-Escolar , Simulação por Computador , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Método de Monte Carlo , Imagens de Fantasmas , Fótons , Doses de Radiação , Proteção Radiológica/métodos , Radiometria/métodos
8.
J Am Chem Soc ; 143(10): 3993-4004, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33663211

RESUMO

Among the central themes in synthetic chemistry is the establishment of novel strategies that usher in the development of more efficient and mild reactions and also expand the chemical space for asymmetric catalysis. Herein, we present an approach to revitalize the Cp*Ir(κ2-LX) system as a catalyst toward alkene difunctionalizations via a nitrenoid-mediated pathway. A key strategy is tuning the orbital symmetry of the key Ir nitrenoid intermediates by ligand modification to impart the desired catalytic activity with the suppression of catalyst deactivation. On the basis of a frontier molecular orbital (FMO) analysis, we systematically engineered a new catalyst system capable of a stepwise nitrenoid transfer to allow for nucleophile incorporation. Using the catalytic protocol, a range of difunctionalized lactams can be produced in a diastereoselective manner with various nucleophiles. Mechanistic investigations revealed that the ligand plays a crucial role in both nitrenoid-delivery and stereoselectivity-determining steps. The current mechanistic platform also enabled the development of new asymmetric methods for introducing two-point chirality in (oxy-alkyl)lactam products with excellent enantioselectivity.

9.
Anal Chem ; 93(34): 11765-11774, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34387479

RESUMO

Microelectrodes are widely used for neural signal analysis because they can record high-resolution signals. In general, the smaller the size of the microelectrode for obtaining a high-resolution signal, the higher the impedance and noise value of the electrodes. Therefore, to improve the signal-to-noise ratio (SNR) of neural signals, it is important to develop microelectrodes with low impedance and noise. In this research, an Au hierarchical nanostructure (AHN) was deposited to improve the electrochemical surface area (ECSA) of a microelectrode. Au nanostructures on different scales were deposited on the electrode surface in a hierarchical structure using an electrochemical deposition method. The AHN-modified microelectrode exhibited an average of 80% improvement in impedance compared to a bare microelectrode. Through electrochemical impedance spectroscopy analysis and impedance equivalent circuit modeling, the increase in the ECSA due to the AHN was confirmed. After evaluating the cell cytotoxicity of the AHN-modified microelectrode through an in vitro test, neural signals from rats were obtained in in vivo experiments. The AHN-modified microelectrode exhibited an approximate 9.79 dB improvement in SNR compared to the bare microelectrode. This surface modification technology is a post-treatment strategy used for existing fabricated electrodes, so it can be applied to microelectrode arrays and nerve electrodes made from various structures and materials.


Assuntos
Nanoestruturas , Animais , Espectroscopia Dielétrica , Impedância Elétrica , Microeletrodos , Ratos , Razão Sinal-Ruído
10.
Int J Mol Sci ; 22(18)2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34575986

RESUMO

Amino acids, as nutrients, are expected to improve sleep disorders. This study aimed to evaluate the generation- and age-dependent sleep-improving effects of γ-aminobutyric acid (GABA) and 5-hydroxytryptophan (5-HTP) coadministration. The differentially expressed genes and generation-related behavior after the administration of a GABA/5-HTP mixture were measured in a Drosophila model, while age-related changes in gene expression and oxidative stress-related parameters were measured in a mouse model. The GABA/5-HTP-treated group showed significant behavioral changes compared to the other groups. Sequencing revealed that the GABA/5-HTP mixture influenced changes in nervous system-related genes, including those involved in the regulation of the expression of behavioral and synaptic genes. Additionally, total sleep time increased with age, and nighttime sleep time in the first- and third-generation flies was significantly different from that of the control groups. The GABA/5-HTP mixture induced significant changes in the expression of sleep-related receptors in both models. Furthermore, the GABA/5-HTP mixture reduced levels of ROS and ROS reaction products in an age-dependent manner. Therefore, the increase in behavioral changes caused by GABA/5-HTP mixture administration was effective in eliminating ROS activity across generations and ages.


Assuntos
5-Hidroxitriptofano/farmacologia , Aminoácidos/farmacologia , Locomoção/efeitos dos fármacos , Transtornos do Sono-Vigília/tratamento farmacológico , Ácido gama-Aminobutírico/farmacologia , Envelhecimento/efeitos dos fármacos , Envelhecimento/genética , Envelhecimento/patologia , Animais , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Locomoção/fisiologia , Camundongos , Nutrientes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transtornos do Sono-Vigília/metabolismo , Transtornos do Sono-Vigília/patologia
11.
Nano Lett ; 19(6): 4043-4051, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31074998

RESUMO

Many two-dimensional (2D) semiconductors represented by transition metal dichalcogenides have tunable optical bandgaps in the visible or near IR-range standing as a promising candidate for optoelectronic devices. Despite this potential, however, their photoreactions are not well understood or controversial in the mechanistic details. In this work, we report a unique thickness-dependent photoreaction sensitivity and a switchover between two competing reaction mechanisms in atomically thin chromium thiophosphate (CrPS4), a two-dimensional antiferromagnetic semiconductor. CrPS4 showed a threshold power density 2 orders of magnitude smaller than that for MoS2 obeying a photothermal reaction route. In addition, reaction cross section quantified with Raman spectroscopy revealed distinctive power dependences in the low and high power regimes. On the basis of optical in situ thermometric measurements and control experiments against O2, water, and photon energy, we proposed a photochemical oxidation mechanism involving singlet O2 in the low power regime with a photothermal route for the other. We also demonstrated a highly effective encapsulation with Al2O3 as a protection against the destructive photoinduced and ambient oxidations.

12.
J Org Chem ; 84(20): 13150-13158, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31322347

RESUMO

Regioselective C-H functionalization on quinolines is of high interest to lead to value-added products. Herein, we describe the development of Ru-catalyzed deoxygenative regioselective C8 arylation of quinoline N-oxides with arylboronic esters. Mechanistic studies revealed that it proceeds in a tandem process of arylation and then deoxygenation, wherein both steps were found to be catalytic with the ruthenium species.

13.
J Nanosci Nanotechnol ; 19(10): 6066-6069, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31026909

RESUMO

In this paper, we proposed and fabricated a polysilicon-based four-terminal synaptic transistor. The device has an asymmetric dual-gate structure. The top gate, which uses a thin SiO2 layer as the gate dielectric, is the input terminal of the synaptic transistor, which receives spikes from pre-synaptic neurons. Meanwhile, a nitride trapping layer was inserted between the channel and the bottom gate to serve as a non-volatile memory. The bottom gate is the node that receives the post-neuron feedback signals and adjusts the synaptic weight. With this double-gate structure, the proposed artificial synapse can perform short-/long-term memory operations. In addition to the basic unit cell characteristics, a highly integrated synapse array structure is also proposed. In our array structure, the top gate is tied in the word-line direction to accept the input signal. Drain contacts are also tied in the same direction. With regard to bit-line direction, the source terminals are tied to carry post-synaptic signals and the bottom gate line receives feedback signals from the post-synaptic neurons.


Assuntos
Dióxido de Silício , Transistores Eletrônicos , Memória de Longo Prazo , Neurônios , Sinapses
14.
Pharm Biol ; 57(1): 65-73, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30707852

RESUMO

CONTEXT: γ-Aminobutyric acid (GABA) is the main inhibitory neurotransmitter and it is well established that activation of GABAA receptors favours sleep. l-Theanine, a naturally occurring amino acid first discovered in green tea, is a well-known anti-anxiety supplement with proven relaxation benefits. OBJECTIVE: This study investigated the potential synergistic sleep enhancement effect of GABA/l-theanine mixture. MATERIALS AND METHODS: Pentobarbital-induced sleep test was applied to find proper concentration for sleep-promoting effect in ICR mice. Electroencephalogram (EEG) analysis was performed to investigate total sleeping time and sleep quality in normal SD rats and caffeine-induced awareness model. Real-time polymerase chain reaction (RT-PCR) was applied to investigate whether the sleep-promoting mechanism of GABA/l-theanine mixture involved transcriptional processes. RESULTS: GABA/l-theanine mixture (100/20 mg/kg) showed a decrease in sleep latency (20.7 and 14.9%) and an increase in sleep duration (87.3 and 26.8%) compared to GABA or theanine alone. GABA/l-theanine mixture led to a significant increase in rapid eye movement (REM) (99.6%) and non-REM (NREM) (20.6%) compared to controls. The use of GABA/l-theanine mixture rather than GABA or l-theanine alone restored to normal levels sleep time and quality in the arousal animal model. The administration of GABA/l-theanine led to increased expression of GABA and the glutamate GluN1 receptor subunit. CONCLUSIONS: GABA/l-theanine mixture has a positive synergistic effect on sleep quality and duration as compared to the GABA or l-theanine alone. The increase in GABA receptor and GluN1 expression is attributed to the potential neuromodulatory properties of GABA/l-theanine combination, which seems to affect sleep behaviour.


Assuntos
Glutamatos/farmacologia , Latência do Sono/efeitos dos fármacos , Sono de Ondas Lentas/efeitos dos fármacos , Ácido gama-Aminobutírico/farmacologia , Animais , Sinergismo Farmacológico , Quimioterapia Combinada , Camundongos , Camundongos Endogâmicos ICR , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Receptores de Glutamato/metabolismo
15.
AAPS PharmSciTech ; 18(8): 3129-3139, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28526986

RESUMO

The purpose of the present study was to develop a rebamipide (RBM) gastro-retentive (GR) tablet by implementing quality by design (QbD). RBM GR tablets were prepared using a sublimation method. Quality target product profile (QTPP) and critical quality attributes (CQAs) of the RBM GR tablets were defined according to the preliminary studies. Factors affecting the CQAs were prioritized using failure mode and effects analysis (FMEA). Design space and optimum formulation were established through a mixture design. The validity of the design space was confirmed using runs within the area. The QTPP of the RBM GR tablets was the orally administered GR tablet containing 300 mg of RBM taken once daily. Based on the QTPP, dissolution rate, tablet friability, and floating property were chosen as CQAs. According to the risk assessment, the amount of sustained-release agent, sublimating material, and diluent showed high-risk priority number (RPN) values above 40. Based on the RPN, these factors were further investigated using mixture design methodology. Design space of formulations was depicted as an overlaid contour plot and the optimum formulation to satisfy the desired responses was obtained by determining the expected value of each response. The similarity factor (f2) of the release profile between predicted response and experimental response was 89.463, suggesting that two release profiles are similar. The validity of the design space was also confirmed. Consequently, we were able to develop the RBM GR tablets by implementing the QbD concept. These results provide useful information for development of tablet formulations using the QbD.


Assuntos
Alanina/análogos & derivados , Antiulcerosos/química , Antiulcerosos/metabolismo , Quinolonas/química , Quinolonas/metabolismo , Alanina/química , Alanina/metabolismo , Preparações de Ação Retardada/química , Preparações de Ação Retardada/metabolismo , Composição de Medicamentos , Liberação Controlada de Fármacos , Excipientes , Fármacos Gastrointestinais/química , Fármacos Gastrointestinais/metabolismo , Comprimidos
16.
Proc Natl Acad Sci U S A ; 110(10): 3800-5, 2013 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-23431188

RESUMO

The N-end rule pathway is a proteolytic system in which destabilizing N-terminal residues of short-lived proteins act as degradation determinants (N-degrons). Substrates carrying N-degrons are recognized by N-recognins that mediate ubiquitylation-dependent selective proteolysis through the proteasome. Our previous studies identified the mammalian N-recognin family consisting of UBR1/E3α, UBR2, UBR4/p600, and UBR5, which recognize destabilizing N-terminal residues through the UBR box. In the current study, we addressed the physiological function of a poorly characterized N-recognin, 570-kDa UBR4, in mammalian development. UBR4-deficient mice die during embryogenesis and exhibit pleiotropic abnormalities, including impaired vascular development in the yolk sac (YS). Vascular development in UBR4-deficient YS normally advances through vasculogenesis but is arrested during angiogenic remodeling of primary capillary plexus associated with accumulation of autophagic vacuoles. In the YS, UBR4 marks endoderm-derived, autophagy-enriched cells that coordinate differentiation of mesoderm-derived vascular cells and supply autophagy-generated amino acids during early embryogenesis. UBR4 of the YS endoderm is associated with a tissue-specific autophagic pathway that mediates bulk lysosomal proteolysis of endocytosed maternal proteins into amino acids. In cultured cells, UBR4 subpopulation is degraded by autophagy through its starvation-induced association with cellular cargoes destined to autophagic double membrane structures. UBR4 loss results in multiple misregulations in autophagic induction and flux, including synthesis and lipidation/activation of the ubiquitin-like protein LC3 and formation of autophagic double membrane structures. Our results suggest that UBR4 plays an important role in mammalian development, such as angiogenesis in the YS, in part through regulation of bulk degradation by lysosomal hydrolases.


Assuntos
Proteínas Associadas aos Microtúbulos/fisiologia , Ubiquitina-Proteína Ligases/fisiologia , Saco Vitelino/irrigação sanguínea , Saco Vitelino/enzimologia , Animais , Autofagia/genética , Autofagia/fisiologia , Proteínas de Ligação a Calmodulina/antagonistas & inibidores , Proteínas de Ligação a Calmodulina/genética , Proteínas de Ligação a Calmodulina/fisiologia , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Proteínas do Citoesqueleto/antagonistas & inibidores , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/fisiologia , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Endoderma/irrigação sanguínea , Endoderma/citologia , Endoderma/enzimologia , Feminino , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Mesoderma/irrigação sanguínea , Mesoderma/citologia , Mesoderma/enzimologia , Redes e Vias Metabólicas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/deficiência , Proteínas Associadas aos Microtúbulos/genética , Neovascularização Fisiológica/genética , Gravidez , Ubiquitina-Proteína Ligases/deficiência , Ubiquitina-Proteína Ligases/genética , Saco Vitelino/citologia , Saco Vitelino/embriologia
17.
Chem Pharm Bull (Tokyo) ; 64(10): 1445-1449, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27725499

RESUMO

The aims of this study were to improve in vitro dissolution property of poorly water-soluble everolimus (EVR) for enhanced bioavailability without using organic solvents and characterize the effects of microfluidization and freeze-drying on physicochemical properties of EVR nanosuspension and nanoparticle, respectively. EVR nanosuspension was prepared using microfluidization with various types and concentrations of stabilizers. After that, it was solidified into nanoparticle using freeze-drying with various concentrations of xylitol, a cryoprotectant. The particle size, zeta potential, physical stability, and chemical stability of EVR nanosuspension and nanoparticle were measured. In vitro release of EVR nanoparticle was also measured and compared with that of physical mixture. Zero point five percent (w/w) poloxamer 407 (P407) was chosen as the stabilizer considering particle size, zeta potential, and yield of EVR nanosuspension. Freeze-drying with 1% (w/w) xylitol improved both physical and chemical stability of EVR nanoparticle. In vitro release test showed improved dissolution property compared to that of physical mixture, implying enhanced bioavailability.


Assuntos
Everolimo/química , Microfluídica/métodos , Nanopartículas/química , Liofilização , Tamanho da Partícula , Solubilidade , Propriedades de Superfície
18.
Chem Pharm Bull (Tokyo) ; 64(8): 1108-17, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27477648

RESUMO

The purposes of the present study were to develop a self-microemulsifying drug delivery system (SMEDDS) containing bortezomib, a proteasome inhibitor. The solubility of the drug was evaluated in 15 pharmaceutical excipients. Combinations of oils, surfactants and cosurfactants were screened by drawing pseudo-ternary phase diagrams. The system exhibiting the largest region of microemulsion was considered optimal. Bortezomib SMEDDS spontaneously formed a microemulsion when diluted with an aqueous medium with a median droplet size of approximately 20-30 nm. In vitro release studies showed that the SMEDDS had higher initial release rates for the drug when compared with the raw drug material alone. Measurement of the viscosity, size, and ion conductivity indicated that a phase inversion from water in an oil system to oil in a water system occurred when the weight ratio of the water exceeded 30% of the entire microemulsion system. In a pharmacokinetics study using rats, the bortezomib microemulsion failed to improve the bioavailability of the drug. The reason was assumed to be degradation of the drug in the microemulsion in the gastrointestinal tract. However, bortezomib in Labrasol(®) solution (an aqueous solution containing 0.025% Labrasol(®)) showed significantly increased area under the curve from 0-24 h (AUC0-24 h) and maximum plasma concentration (Cmax) values compared to the drug suspension. The findings of this study imply that oral delivery of a bortezomib and colloidal system containing Labrasol(®) could be an effective strategy for the delivery of bortezomib.


Assuntos
Bortezomib/administração & dosagem , Bortezomib/farmacocinética , Composição de Medicamentos , Sistemas de Liberação de Medicamentos/métodos , Animais , Disponibilidade Biológica , Emulsões , Trato Gastrointestinal/metabolismo , Glicerídeos/química , Masculino , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Solubilidade , Propriedades de Superfície , Viscosidade
19.
BMC Genomics ; 16: 279, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25888140

RESUMO

BACKGROUND: Despite the recent identification of several prognostic gene signatures, the lack of common genes among experimental cohorts has posed a considerable challenge in uncovering the molecular basis underlying hepatocellular carcinoma (HCC) recurrence for application in clinical purposes. To overcome the limitations of individual gene-based analysis, we applied a pathway-based approach for analysis of HCC recurrence. RESULTS: By implementing a permutation-based semi-supervised principal component analysis algorithm using the optimal principal component, we selected sixty-four pathways associated with hepatitis B virus (HBV)-positive HCC recurrence (p < 0.01), from our microarray dataset composed of 142 HBV-positive HCCs. In relation to the public HBV- and public hepatitis C virus (HCV)-positive HCC datasets, we detected 46 (71.9%) and 18 (28.1%) common recurrence-associated pathways, respectively. However, overlap of recurrence-associated genes between datasets was rare, further supporting the utility of the pathway-based approach for recurrence analysis between different HCC datasets. Non-supervised clustering of the 64 recurrence-associated pathways facilitated the classification of HCC patients into high- and low-risk subgroups, based on risk of recurrence (p < 0.0001). The pathways identified were additionally successfully applied to discriminate subgroups depending on recurrence risk within the public HCC datasets. Through multivariate analysis, these recurrence-associated pathways were identified as an independent prognostic factor (p < 0.0001) along with tumor number, tumor size and Edmondson's grade. Moreover, the pathway-based approach had a clinical advantage in terms of discriminating the high-risk subgroup (N = 12) among patients (N = 26) with small HCC (<3 cm). CONCLUSIONS: Using pathway-based analysis, we successfully identified the pathways involved in recurrence of HBV-positive HCC that may be effectively used as prognostic markers.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Hepatite B/diagnóstico , Neoplasias Hepáticas/diagnóstico , Adulto , Algoritmos , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/epidemiologia , Análise por Conglomerados , Bases de Dados Factuais , Intervalo Livre de Doença , Feminino , Hepacivirus/isolamento & purificação , Hepatite B/complicações , Hepatite B/virologia , Vírus da Hepatite B/isolamento & purificação , Humanos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Análise de Componente Principal , Prognóstico , Risco
20.
Phytother Res ; 29(12): 1910-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26400610

RESUMO

Diabetic retinopathy is a major diabetic complication predominantly caused by vascular endothelial growth factor (VEGF)-induced vascular permeability in the retina; however, treatments targeting glycemic control have not been successful. Here, we investigated the protective effect of dammarenediol-II, a precursor of triterpenoid saponin biosynthesis, on VEGF-induced vascular leakage using human umbilical vein endothelial cells (HUVECs) and diabetic mice. We overproduced the compound in transgenic tobacco expressing Panax ginseng dammarenediol-II synthase gene and purified using column chromatography. Analysis of the purified compound using a gas chromatography-mass spectrometry system revealed identical retention time and fragmentation pattern to those of authentic standard dammarenediol-II. Dammarenediol-II inhibited VEGF-induced intracellular reactive oxygen species generation, but it had no effect on the levels of intracellular Ca(2+) in HUVECs. We also found that dammarenediol-II inhibited VEGF-induced stress fiber formation and vascular endothelial-cadherin disruption, both of which play critical roles in modulating endothelial permeability. Notably, microvascular leakage in the retina of diabetic mice was successfully inhibited by intravitreal dammarenediol-II injection. Our results suggest that the natural drug dammarenediol-II may have the ability to prevent diabetic microvascular complications, including diabetic retinopathy.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Retinopatia Diabética/tratamento farmacológico , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Saponinas/farmacologia , Triterpenos/farmacologia , Fator A de Crescimento do Endotélio Vascular/farmacologia , Alquil e Aril Transferases/genética , Animais , Cálcio/metabolismo , Diabetes Mellitus Experimental/complicações , Cromatografia Gasosa-Espectrometria de Massas , Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , Plantas Geneticamente Modificadas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Retina/efeitos dos fármacos , Retina/fisiopatologia , Saponinas/biossíntese , Nicotiana/genética , Nicotiana/metabolismo
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