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1.
Nature ; 630(8015): 59-63, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38750357

RESUMO

Ab initio calculations have an essential role in our fundamental understanding of quantum many-body systems across many subfields, from strongly correlated fermions1-3 to quantum chemistry4-6 and from atomic and molecular systems7-9 to nuclear physics10-14. One of the primary challenges is to perform accurate calculations for systems where the interactions may be complicated and difficult for the chosen computational method to handle. Here we address the problem by introducing an approach called wavefunction matching. Wavefunction matching transforms the interaction between particles so that the wavefunctions up to some finite range match that of an easily computable interaction. This allows for calculations of systems that would otherwise be impossible owing to problems such as Monte Carlo sign cancellations. We apply the method to lattice Monte Carlo simulations15,16 of light nuclei, medium-mass nuclei, neutron matter and nuclear matter. We use high-fidelity chiral effective field theory interactions17,18 and find good agreement with empirical data. These results are accompanied by insights on the nuclear interactions that may help to resolve long-standing challenges in accurately reproducing nuclear binding energies, charge radii and nuclear-matter saturation in ab initio calculations19,20.

2.
ACS Meas Sci Au ; 3(6): 393-403, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38145025

RESUMO

With the definition of therapeutics now encompassing transplanted or engineered cells and their molecular products, there is a growing scientific necessity for analytics to understand this new category of drugs. This Perspective highlights the recent development of new measurement science on label-free single cell analysis, nanosensor chemical cytometry (NCC), and their potential for cellular therapeutics and precision medicine. NCC is based on microfluidics integrated with fluorescent nanosensor arrays utilizing the optical lensing effect of a single cell to real-time extract molecular properties and correlate them with physical attributes of single cells. This new class of cytometry can quantify the heterogeneity of the multivariate physicochemical attributes of the cell populations in a completely label-free and nondestructive way and, thus, suggest the vein-to-vein conditions for the safe therapeutic applications. After the introduction of the NCC technology, we suggest the technological development roadmap for the maturation of the new field: from the sensor/chip design perspective to the system/software development level based on hardware automation and deep learning data analytics. The advancement of this new single cell sensing technology is anticipated to aid rich and multivariate single cell data setting and support safe and reliable cellular therapeutics. This new measurement science can lead to data-driven personalized precision medicine.

3.
Arch Pharm Res ; 46(3): 192-205, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36840853

RESUMO

Induction of the brown adipocyte-like phenotype in white adipocytes (fat browning) is considered a promising therapeutic strategy to treat obesity. Naringin, a citrus flavonoid, has antioxidant, anti-inflammatory, and anticancer activities. We examined the application of naringin as an anti-obesity compound based on an investigation of its induction of fat browning in 3T3-L1 adipocytes. Naringin did not induce lipid accumulation in differentiated 3T3-L1 adipocytes. Additionally, naringin reduced the expression levels of proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein alpha (C/EBPα) involved in adipogenesis during lipid metabolism and increased the levels of PPARα and adiponectin involved in fatty acid oxidation. The expression levels of fat browning markers uncoupling protein 1 (UCP1; involved in thermogenesis) and PR domain containing 16 (PRDM16) increased. In addition, naringin treatment resulted in the activation of PPARγ coactivator 1-alpha (PGC-1α), a factor related to UCP1 transcription and mitochondrial biogenesis. Moreover, the expression of beige adipocyte-specific genes such as Cd137, Cited1, Tbx1, and Tmem26 was also induced. The small multi-lipid droplets characteristic of beige adipocytes indicated that naringin treatment increased the levels of all lipolysis markers (hormone-sensitive lipase [HSL], adipose triglyceride lipase [ATGL], perilipin [PLIN], and protein kinase A [PKA]). Adenosine monophosphate-activated protein kinase (AMPK) and UCP1 levels increased by treatment with naringin alone; this was possibly mediated by the stimulation of the AMPK signaling pathway. According to mechanistic studies, naringin activated the thermogenic protein UCP1 via the AMPK signaling pathway. In conclusion, naringin induces fat browning and is a promising therapeutic agent for metabolic disorders based on the regulation of lipid metabolism.


Assuntos
Proteínas Quinases Ativadas por AMP , PPAR gama , Animais , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Células 3T3-L1 , PPAR gama/metabolismo , Adipócitos Marrons/metabolismo , Transdução de Sinais , Obesidade/metabolismo , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
4.
J Control Release ; 354: 244-259, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36596340

RESUMO

Nanoparticle (NP) technology holds significant promise to mediate targeted drug delivery to specific organs in the body. Understanding the 3D biodistribution of NPs in heterogeneous environments such as the tumor tissue can provide crucial information on efficacy, safety and potential clinical outcomes. Here we present a novel end-to-end workflow, VIOLA, which makes use of tissue clearing methodology in conjunction with high resolution imaging and advanced 3D image processing to quantify the spatiotemporal 3D biodistribution of fluorescently labeled ACCURIN® NPs. Specifically, we investigate the spatiotemporal biodistribution of NPs in three different murine tumor models (CT26, EMT6, and KPC-GEM) of increasing complexity and translational relevance. We have developed new endpoints to characterize NP biodistribution at multiple length scales. Our observations reveal that the macroscale NP biodistribution is spatially heterogeneous and exhibits a gradient with relatively high accumulation at the tumor periphery that progressively decreases towards the tumor core in all the tumor models. Microscale analysis revealed that NP extravasation from blood vessels increases in a time dependent manner and plateaus at 72 h post injection. Volumetric analysis and pharmacokinetic modeling of NP biodistribution in the vicinity of the blood vessels revealed that the local NP density exhibits a distance dependent spatiotemporal biodistribution which provide insights into the dynamics of NP extravasation in the tumor tissue. Our data represents a comprehensive analysis of NP biodistribution at multiple length scales in different tumor models providing unique insights into their spatiotemporal dynamics. Specifically, our results show that NPs exhibit a dynamic equilibrium with macroscale heterogeneity combined with microscale homogeneity.


Assuntos
Nanopartículas , Neoplasias , Viola , Animais , Camundongos , Distribuição Tecidual , Sistemas de Liberação de Medicamentos
5.
Nanomaterials (Basel) ; 12(10)2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35630927

RESUMO

Understanding the long-term stability of MoS2 is important for various optoelectronic applications. Herein, we show that the long-term exposure to an oxygen atmosphere for up to a few months results in zigzag (zz)-directional line unzipping of the MoS2 basal plane. In contrast to exposure to dry or humid N2 atmospheres, dry O2 treatment promotes the initial formation of line defects, mainly along the armchair (ac) direction, and humid O2 treatment further promotes ac line unzipping near edges. Further incubation of MoS2 for a few months in an O2 atmosphere results in massive zz-directional line unzipping. The photoluminescence and the strain-doping plot based on two prominent bands in the Raman spectrum show that, in contrast to dry-N2-treated MoS2, the O2-treated MoS2 primarily exhibits hole doping, whereas humid-O2-treated MoS2 mainly exists in a neutral charge state with tension. This study provides a guideline for MoS2 preservation and a further method for generating controlled defects.

6.
Int J Toxicol ; 40(1): 40-51, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33148080

RESUMO

Clinical use of the chemotherapeutic agent vincristine (VCR) is limited by chemotherapy-induced peripheral neuropathy (CiPN). A new formulation of VCR encapsulated by nanoparticles has been proposed and developed to alleviate CiPN. We hypothesized in nonclinical animals that the nanoparticle drug would be less neurotoxic due to different absorption and distribution properties to the peripheral nerve from the unencapsulated free drug. Here, we assessed whether VCR encapsulation in nanoparticles alleviates CiPN using behavioral gait analysis (CatWalk), histopathologic and molecular biological (RT-qPCR) approaches. Adult male C57BL/6 mice were assigned to 3 groups (empty nanoparticle, nano-VCR, solution-based VCR, each n = 8). After 15 days of dosing, animals were euthanized for tissue collection. It was shown that intraperitoneal administration of nano-VCR (0.15 mg/kg, every other day) and the empty nanoparticle resulted in no changes in gait parameters; whereas, injection of solution-based VCR resulted in decreased run speed and increased step cycle and stance (P < 0.05). There were no differences in incidence and severity of degeneration in the sciatic nerves between the nano-VCR-dosed and solution-based VCR-dosed animals. Likewise, decreased levels of a nervous tissue-enriched microRNA-183 in circulating blood did not show a significant difference between the nano- and solution-based VCR groups (P > 0.05). Empty nanoparticle administration did not cause any behavioral, microRNA, or structural changes. In conclusion, this study suggests that the nano-VCR formulation may alleviate behavioral changes in CiPN, but it does not improve the structural changes of CiPN in peripheral nerve. Nanoparticle properties may need to be optimized to improve biological observations.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Comportamento Animal/efeitos dos fármacos , Marcha/efeitos dos fármacos , Nanopartículas/toxicidade , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Vincristina/toxicidade , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL
7.
Technol Health Care ; 26(S1): 291-306, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29710757

RESUMO

This study was conducted according to the method presented in the Republic of Korea Pharmacopoeia 11th Revision, aseptic test method to evaluate the suitability of sterilization for a sterile needle (4 Pin Multi-needle). In this study, four tests were conducted: sterility test, cytotoxicity test, acute toxicity test, skin sensitization test. First, in the aseptic test, the microorganism was not proliferated in the aseptic test of the medium. As a result of the performance test of the medium, it was confirmed that the microorganism developed within 3 days and the fungus was evident within 5 days. Based on this, it was confirmed that the medium was suitable, and as a result of the aseptic test, the development of microorganisms was not observed during the total culture period. Based on these results, tests were conducted which were confirmed to be suitable for aseptic testing because the development of bacteria on the provided samples was not recognized. For cytotoxicity tests ISO10993-5; 2009 (Biological Evaluation of Medical Devices, Part 5: Test for in vitro Cytotoxicity). As a result, the MEM eluate of the test substance caused very slight cytotoxicity to the fibroblasts of the mouse and was judged to be Grade 1 (Slightly cytotoxic) according to the judgment standard of ISO 10993-5. On the other hand, solvent control, negative control and positive control showed the expected results on the test. Acute Toxicity Test Results: It was judged that there was no systemic toxicity change when ICR mice were treated with 50 mL/kg B.W. of the eluate of sterile injectable needle for 72 hours. Skin sensitization test result: The Hartley guinea pig was evaluated as a substance which is evaluated as a substance which does not induce any skin reaction when skin sensitization is applied to the dissected material of the sterile injectable needle and is weak in skin sensitivity. Based on the above tests, we will study the stability and efficacy of more reliable medical devices based on the verification and performance of medical devices.


Assuntos
Mesoterapia/métodos , Agulhas/microbiologia , Esterilização/métodos , Animais , Dermatite Alérgica de Contato/microbiologia , Fibroblastos/microbiologia , Cobaias , Camundongos , Reprodutibilidade dos Testes , República da Coreia , Testes Cutâneos , Esterilização/normas , Testes de Toxicidade
8.
J Biomed Mater Res A ; 87(4): 913-20, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-18228250

RESUMO

Mapping the drug distribution in a polymeric film and following the subsequent changes that result during and after drug release is important to better understand the mechanism of drug release. This understanding leads to more efficiently designed tailor-made release profiles for drug-containing biomedical devices. Coherent anti-Stokes Raman scattering (CARS) microscopy was used for in situ imaging of local drug distribution in polymeric films, taking advantage of the three-dimensional (3D) resolution, high speed, high sensitivity, and noninvasiveness of the technology. Additionally, the morphological changes of poly(styrene-b-isobutylene-b-styrene) (SIBS) films during paclitaxel release were characterized by scanning electron microscopy, and drug release was quantitatively determined by high performance liquid chromatography. The time-dependent changes in the 3D distribution of paclitaxel in the polymer film were visualized using CARS microscopy. CARS images showed that the paclitaxel was uniformly distributed throughout the SIBS matrix. Changes in the paclitaxel distribution during release were monitored using depth intensity profiles and showed that, upon exposure of the paclitaxel-loaded film to a release medium, the quantitative CARS intensity of paclitaxel decreased. These results indicate that paclitaxel was dissolved and depleted from the SIBS film during in vitro drug elution, supporting the use of CARS microscopy as an effective nondestructive technique for chemical imaging of paclitaxel elution dynamics in polymer films.


Assuntos
Antineoplásicos Fitogênicos , Paclitaxel , Polímeros , Análise Espectral Raman/métodos , Estirenos , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/metabolismo , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Teste de Materiais , Paclitaxel/química , Paclitaxel/metabolismo , Polímeros/química , Polímeros/metabolismo , Stents , Estirenos/química , Estirenos/metabolismo , Propriedades de Superfície
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