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1.
Nano Lett ; 24(11): 3448-3455, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38452056

RESUMO

Unlike graphene derived from graphite, borophenes represent a distinct class of synthetic two-dimensional materials devoid of analogous bulk-layered allotropes, leading to covalent bonding within borophenes instead of van der Waals (vdW) stacking. Our investigation focuses on 665 vdW-stacking boron bilayers to uncover potential bulk-layered boron allotropes through vdW stacking. Systematic high-throughput screening and stability analysis reveal a prevailing inclination toward covalently bonded layers in the majority of boron bilayers. However, an intriguing outlier emerges in δ5 borophene, demonstrating potential as a vdW-stacking candidate. We delve into electronic and topological structural similarities between δ5 borophene and graphene, shedding light on the structural integrity and stability of vdW-stacked boron structures across bilayers, multilayers, and bulk-layered allotropes. The δ5 borophene analogues exhibit metallic properties and characteristics of phonon-mediated superconductors, boasting a critical temperature near 22 K. This study paves the way for the concept of "borophite", a long-awaited boron analogue of graphite.

2.
Angew Chem Int Ed Engl ; 61(36): e202205902, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-35751134

RESUMO

Synthetically directing T-cells against tumors emerges as a promising strategy in immunotherapy, while it remains challenging to smartly engage T cells with tunable immune response. Herein, we report an intelligent molecular platform to engineer T-cell recognition for selective activation to potently kill cancer cells. To this end, we fabricated a hybrid conjugate that uses a click-type DNA-protein conjugation to equip the T cell-engaging antibody with two distinct programmable DNA nanoassemblies. By integrating multiple aptameric antigen-recognitions within a dynamic DNA circuit, we achieved combinatorial recognition of triple-antigens on cancer cells for selective T-cell activation after high-order logic operation. Moreover, by coupling a DNA nanostructure, we precisely defined the valence of the antigen-binding aptamers to tune avidity, realizing effective tumor elimination in vitro and in vivo. Together, we present a versatile and programmable strategy for synthetic immunotherapy.


Assuntos
Neoplasias , Linfócitos T , Anticorpos , Antígenos , DNA/química , Humanos , Imunoterapia , Neoplasias/terapia
3.
Zhen Ci Yan Jiu ; 46(6): 486-91, 2021 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-34190452

RESUMO

As the living standard improves and population aging continues, the traditional cupping manipulations fail to meet the ever-growing demand for high-quality medical and health services. Aiming to address such shortcomings of traditional cupping manipulations as difficulty in achieving real-time temperature control, unsatisfactory negative pressure effect and inconve-nience to observe the internal situation, we have developed a glass cupping device with closed-loop control that could automatically integrate the acupoint-symptom analysis models. This device, composed of two cups, boasts high safety, good sealing and sound economic efficiency. The PT100 thermocouple probe and the pressure sensor equipped with P89C668 single chip microcomputer enable the multimodal integration of temperature and pressure, whose main parameters can be automatically displayed on the LED screen by the built-in data processing device. This glass cupping device with closed-loop control is an updated design for acupuncture and moxibustion based on multidisciplinary resources.


Assuntos
Terapia por Acupuntura , Moxibustão , Pontos de Acupuntura
4.
RSC Adv ; 9(66): 38902-38911, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-35540219

RESUMO

Three cobalt-based coordination polymers [Co(Htatb)(1,3-bimyb)] (1), [Co(Htatb)(bimbp)]·DMF (2), and [Co(Htatb)(1,4-bimyb)]·H2O (3) [H3tatb = 4,4',4''-s-triazine-2,4,6-tribenzoic acid, 1,3-bimyb = 1,3-bis(imidazole-1-ylmethyl)benzene, bimbp = 4,4'-bis(imidazolyl)biphenyl, 1,4-bimyb = 1,4-bis (imidazole-1-ylmethyl)benzene] were synthesized by hydrothermal reactions and characterized by single-crystal X-ray diffraction, thermogravimetric analyses, IR spectroscopy, UV-vis spectroscopy and elemental analysis. Compound 1 shows a double-strand chain structure, due to the intermolecular O-H⋯O hydrogen bonds and aromatic π-π stacking interactions, the adjacent chains are connected to produce a 3D supramolecular structure. Compound 2 shows a 2D structure with a 1D channel. Compound 3 displays a 2D layer structure, furthermore these layers are joined by O-H⋯O hydrogen bonding to generate a four-fold interpenetrating 3D architecture. The fluorescence properties of 1-3 and the magnetic behavior of 1 and 2 have also been investigated. Based on their crystal structures, compounds 1 and 2 were investigated using hybrid DFT methods at the B3LYP/6-31G (d) level. The DFT-BS approach was applied to study the magnetic coupling behavior. The results reveal that the calculated exchange coupling constants J were in good agreement with the experimental data.

5.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 35(3): 275-80, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-23842526

RESUMO

OBJECTIVE: To investigate the methylation Oct4 in orientation induced differentiation in bone marrow mesenchymal stem cells METHODS: Mice BMSCs were isolated and purified from bone marrow by adherent culture,and then identified by morphology and immunocytochemistry.Mouse osteoblastic cells were cultured by bone fragments inoculation,and then identified by alkaline phosphatase(AKP)staining and alizarin red staining.BMSCs were induced to differentiate into osteoblasts in vitro. Indirect immunofluorescence staining and reverse transcription polymerase chain reaction(RT PCR)were used to detect the expressions of Oct4 in BMSCs before and after induction.The methylation status of Oct4 gene in mouse BMSCs was explored by a methylation specific PCR before and after induction RESULTS: The isolated mice BMSCs massively proliferated in vitro and formed cell colones with uniform morphology.Positive expressions of CD29,cKit,and CD44 and negative expression of CD34 were found in the isolated cells.After 10 days[DK]'[DK] induction,both AKP and the alizarin red were positive in cells and osteoblastic cells isolated from mice skull bones.The indirect immunoinfluorescence staining and RT-PCR also showed that the Oct4 expression in the directed differentiation of mouse BMSCs was down-regulated.The CpG island of Otc4 gene promoter in mouse BMSCs became methylated during the induced differentiation. CONCLUSIONS: Mice BMSCs and osteoblasts were successfully cultured in vitro in this studyOct4 may be involved in the maintenance of adult stem cell pluripotency.The down regulated expression of Oct4 gene in mouse BMSCs during the directed differentiation may contribute to the methylation of CpG island in Otc4 gene promoter.


Assuntos
Células da Medula Óssea/citologia , Metilação de DNA , Células-Tronco Mesenquimais/citologia , Fator 3 de Transcrição de Octâmero/metabolismo , Osteoblastos/citologia , Animais , Diferenciação Celular , Células Cultivadas , Ilhas de CpG , Camundongos , Regiões Promotoras Genéticas
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