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1.
Small ; 20(29): e2311299, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38366314

RESUMO

Silicon (Si) anode has attracted broad attention because of its high theoretical specific capacity and low working potential. However, the severe volumetric changes of Si particles during the lithiation process cause expansion and contraction of the electrodes, which induces a repeatedly repair of solid electrolyte interphase, resulting in an excessive consuming of electrolyte and rapid capacity decay. Clearly known the deformation and stress changing at µÎµ resolution in the Si-based electrode during battery operation provides invaluable information for the battery research and development. Here, an in operando approach is developed to monitor the stress evolution of Si anode electrodes via optical fiber Bragg grating (FBG) sensors. By implanting FBG sensor at specific locations in the pouch cells with different Si anodes, the stress evolution of Si electrodes has been systematically investigated, and Δσ/areal capacity is proposed for stress assessment. The results indicate that the differences in stress evolution are nested in the morphological changes of Si particles and the evolution characteristics of electrode structures. The proposed technique provides a brand-new view for understanding the electrochemical mechanics of Si electrodes during battery operation.

2.
Mikrochim Acta ; 191(5): 279, 2024 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647729

RESUMO

The therapeutic effect of gefitinib on colorectal cancer (CRC) is unclear, but it has been reported that stromal cells in the tumor microenvironment may have an impact on drug sensitivity. Herein, we established a microfluidic co-culture system and explored the sensitivity of CRC cells co-cultured with cancer-associated fibroblasts (CAFs) to gefitinib. The system consisted of a multichannel chip and a Petri dish. The chambers in the chip and dish were designed to continuously supply nutrients for long-term cell survival and create chemokine gradients for driving cell invasion without any external equipment. Using this system, the proliferation and invasiveness of cells were simultaneously evaluated by quantifying the area of cells and the migration distance of cells. In addition, the system combined with live cell workstation could evaluate the dynamic drug response of co-cultured cells and track individual cell trajectories in real-time. When CRC cells were co-cultured with CAFs, CAFs promoted CRC cell proliferation and invasion and reduced the sensitivity of cells to gefitinib through the exosomes secreted by CAFs. Furthermore, the cells that migrated out of the chip were collected, and EMT-related markers were determined by immunofluorescent and western blot assays. The results demonstrated that CAFs affected the response of CRC cells to gefitinib by inducing EMT, providing new ideas for further research on the resistance mechanism of gefitinib. This suggests that targeting CAFs or exosomes might be a new approach to enhance CRC sensitivity to gefitinib, and our system could be a novel platform for investigating the crosstalk between tumor cells and CAFs and understanding multiple biological changes of the tumor cells in the tumor microenvironment.


Assuntos
Antineoplásicos , Proliferação de Células , Técnicas de Cocultura , Neoplasias Colorretais , Gefitinibe , Gefitinibe/farmacologia , Humanos , Técnicas de Cocultura/instrumentação , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Proliferação de Células/efeitos dos fármacos , Antineoplásicos/farmacologia , Fibroblastos Associados a Câncer/efeitos dos fármacos , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Movimento Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Linhagem Celular Tumoral , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Exossomos/metabolismo , Exossomos/química , Exossomos/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos
3.
Angew Chem Int Ed Engl ; 63(10): e202318042, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38225208

RESUMO

Ni-rich layered oxides are promising lithium-ion batteries (LIBs) cathode materials for their high reversible capacity, but they suffer from fast structural degradation during cycling. Here, we report the Ce/Gd incorporated single-crystalline LiNi0.83 Co0.07 Mn0.10 O2 (SC-NCM) cathode materials with significantly enhanced cycling stability. The Gd ions are adequately incorporated in SC-NCM while Ce ions are prone to aggregate in the outer surface, resulting in the formation of a high-entropy zone in the near-surface of SC-NCM, including a Gd doped LiCeO2 (LCGO) shell and Ce/Gd dopant-concentrated layer. The high-entropy zone can effectively inhibit the oxygen evolution and prevent the formation of oxygen vacancies. Meanwhile, it leads to a greatly improved H2-H3 phase transformation reversibility and mitigated stress/strain caused by Li-ion extraction/insertion during (de)lithiation process. The synergetic effects of reduced oxygen vacancies concentration and mitigated stress/strain can effectively prevent the in-plane migration of TM ions, lattice planar gliding as well as the formation of intragranular nanocracks. Consequently, Ce/Gd incorporated SC-NCM (SC-NCM@CG2) delivers a high initial discharge specific capacity of 219.7 mAh g-1 at 0.1 C and an excellent cycling stability with a capacity retention of 90.2 % after 100 cycles at 1.0 C.

4.
Anal Chem ; 95(2): 1251-1261, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36583760

RESUMO

Liquid biopsy provides non-invasive and real-time detection for cancer diagnosis, but the lack of specific markers targeted to liquid biopsy components, such as circulating tumor cells (CTCs) and exosomes, has impeded its effective utilization in clinical settings. W3 is an aptamer, and its target has been previously demonstrated to be a predictor of colorectal cancer (CRC) metastasis. Herein, we developed a W3-based molecular beacon (MAB-W3-3G) to specifically detect CTCs and exosomes derived from CRC patients by modifying the W3 sequence and adding a fluorescent group FAM at the 5' end and a quencher group BHQ1 at the 3' end, resulting in a detectable green fluorescence only in the presence of the target. MAB-W3-3G retained features similar to those of the original W3, including high specificity and affinity for metastatic CRC cells, as well as excellent plasma stability. Notably, W3 target-positive CTCs were visualized, positive exosomes were quantified in CRC patients' whole blood without any sample pretreatment, and both detections could be finished in one step without any routine washing procedures. For CRC, the W3 target-positive CTC enumeration in metastasis was higher than that in non-metastasis (p < 0.01), and the quantitation of positive exosomes was correlated with CRC patients (p < 0.0001). Moreover, the MAB-W3-3G-based simultaneous detection of CTCs and exosomes was proven to have the potential for more precise clinical diagnosis. In conclusion, MAB-W3-3G could detect CTCs and exosomes in the blood samples of tumor patients with simple manipulation, rapid analysis, and high specificity, providing an effective liquid biopsy tool for the prediction of CRC.


Assuntos
Neoplasias Colorretais , Exossomos , Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patologia , Exossomos/patologia , Neoplasias Colorretais/patologia , Oligonucleotídeos , Biópsia Líquida , Biomarcadores Tumorais
5.
Small ; 19(48): e2303864, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37525330

RESUMO

Silicon (Si) is regarded as one of the most promising anode materials for high-performance lithium-ion batteries (LIBs). However, how to mitigate its poor intrinsic conductivity and the lithiation/delithiation-induced large volume change and thus structural degradation of Si electrodes without compromising their energy density is critical for the practical application of Si in LIBs. Herein, an integration strategy is proposed for preparing a compact micron-sized Si@G/CNF@NC composite with a tight binding and dual-encapsulated architecture that can endow it with superior electrical conductivity and deformation resistance, contributing to excellent cycling stability and good rate performance in thick electrode. At an ultrahigh mass loading of 10.8 mg cm-2 , the Si@G/CNF@NC electrode also presents a large initial areal capacity of 16.7 mA h cm-2 (volumetric capacity of 2197.7 mA h cm-3 ). When paired with LiNi0.95 Co0.02 Mn0.03 O2 , the pouch-type full battery displays a highly competitive gravimetric (volumetric) energy density of ≈459.1 Wh kg-1 (≈1235.4 Wh L-1 ).

6.
Analyst ; 147(1): 187-195, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34874026

RESUMO

Malignant melanoma is regarded as the most aggressive form of skin cancer, and is responsible for most death caused by skin cancer. BRAF mutations occur in approximately 40-50% of melanomas, with V600E being the most common mutation. Testing for BRAF mutations and targeted therapy have markedly improved long-term survival for patients with BRAF-mutated melanoma. Here, we report two aptamers, CH1 and CH5 generated by Cell-SELEX, against BRAF V600E-mutated human melanoma cells A375. The two aptamers exhibited high affinity to target cells with low dissociation constants (Kd) in the nanomolar range. Furthermore, the binding of two aptamers to target cells was independent of incubation temperature, and their molecular targets were demonstrated to be membrane proteins on the cell surface. We also demonstrated that aptamer CH1 was able to bind to metastatic colorectal cancer cells harboring BRAF V600E mutation, indicating a relationship between aptamer CH1 and BRAF V600E-related metastatic cancer. Owing to the structure stability and high selectivity to BRAF V600E-mutated targeting cells, aptamer CH1 holds great potential as a molecular probe for the detection of BRAF V600E-mutated metastatic melanoma.


Assuntos
Melanoma , Proteínas Proto-Oncogênicas B-raf , DNA de Cadeia Simples , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Proteínas de Membrana , Oligonucleotídeos , Proteínas Proto-Oncogênicas B-raf/genética
7.
Anal Bioanal Chem ; 412(30): 8451, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32968853

RESUMO

The authors would like to call the reader's attention to the fact that unfortunately the name of Jianzhang Pan was missing as co-author of this contribution.

8.
Anal Bioanal Chem ; 412(13): 3037-3049, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32249344

RESUMO

The efficacy of targeted therapy is associated with multi-gene mutation status. Carrying out effective multi-genotyping analysis in combination has been a challenge in clinical settings. We therefore developed a droplet-based capillary electrophoresis (CE) system coupled with PCR-restriction fragment length polymorphism (PCR-RFLP) technology to detect multi-gene mutations from a small volume of samples. A 16 × 16 200-nL droplet array for sample encapsulation was constructed on a glass chip. The electrophoresis system consisted of a tapered vertical capillary filled with polyvinylpyrrolidone, a laser-induced fluorescence detector, and a high voltage power supply. Notably, a droplet-based electrokinetic sample introduction method and a "∩" shape capillary were developed to facilitate consecutive droplet sampling using a home-made automatic control module. The DL2000 DNA marker was consecutively separated, achieving high migration time and plate number reproducibility. The system was further applied to detect PCR-RFLP products. For colorectal cancer (CRC) cell lines, KRAS, BRAF, and PIK3CA were genotyped with a sensitivity of 0.25%. For CRC patient specimens, 30 samples were consecutively and automatically multi-genotyped without inter-sample contamination, with a lowest mutation frequency of 0.37%. For the first time, we developed a droplet-based CE system for consecutive DNA analysis with low sample consumption. This automated CE system could be further developed to integrate the full process of gene mutation detection, serving as a more effective platform for individualised therapy.


Assuntos
Neoplasias Colorretais/genética , Eletroforese Capilar/métodos , Mutação , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Linhagem Celular Tumoral , Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias Colorretais/patologia , Genes ras , Humanos , Proteínas Proto-Oncogênicas B-raf/genética , Reprodutibilidade dos Testes
9.
Anal Chem ; 90(5): 3253-3261, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29431425

RESUMO

Angiogenesis is critical for tumor progression and metastasis, and it progresses through orchestral multicellular interactions. Thus, there is urgent demand for high-throughput tumor angiogenesis assays for concurrent examination of multiple factors. For investigating tumor angiogenesis, we developed a microfluidic droplet array-based cell-coculture system comprising a two-layer polydimethylsiloxane chip featuring 6 × 9 paired-well arrays and an automated droplet-manipulation device. In each droplet-pair unit, tumor cells were cultured in 3D in one droplet by mixing cell suspensions with Matrigel, and in the other droplet, human umbilical vein endothelial cells (HUVECs) were cultured in 2D. Droplets were fused by a newly developed fusion method, and tumor angiogenesis was assayed by coculturing tumor cells and HUVECs in the fused droplet units. The 3D-cultured tumor cells formed aggregates harboring a hypoxic center-as observed in vivo-and secreted more vascular endothelial growth factor (VEGF) and more strongly induced HUVEC tubule formation than did 2D-cultured tumor cells. Our single array supported 54 assays in parallel. The angiogenic potentials of distinct tumor cells and their differential responses to antiangiogenesis agent, Fingolimod, could be investigated without mutual interference in a single array. Our droplet-based assay is convenient to evaluate multicellular interaction in high throughput in the context of tumor sprouting angiogenesis, and we envision that the assay can be extensively implementable for studying other cell-cell interactions.


Assuntos
Comunicação Celular/fisiologia , Técnicas de Cocultura/métodos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Ensaios de Triagem em Larga Escala/métodos , Neovascularização Patológica/fisiopatologia , Inibidores da Angiogênese/farmacologia , Animais , Comunicação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Células Endoteliais , Cloridrato de Fingolimode/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Microfluídica/métodos , Neovascularização Patológica/tratamento farmacológico , Ratos
10.
BMC Cancer ; 16: 454, 2016 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-27405731

RESUMO

BACKGROUND: The PIK3CA (H1047R) mutation is considered to be a potential predictive biomarker for EGFR-targeted therapies. In this study, we developed a novel PCR-PFLP approach to detect the PIK3CA (H1047R) mutation in high effectiveness. METHODS: A 126-bp fragment of PIK3CA exon-20 was amplified by PCR, digested with FspI restriction endonuclease and separated by 3 % agarose gel electrophoresis for the PCR-RFLP analysis. The mutant sequence of the PIK3CA (H1047R) was spiked into the corresponding wild-type sequence in decreasing ratios for sensitivity analysis. Eight-six cases of formalin-fixed paraffin-embedded colorectal cancer (CRC) specimens were subjected to PCR-RFLP to evaluate the applicability of the method. RESULTS: The PCR-RFLP method had a capability to detect as litter as 0.4 % of mutation, and revealed 16.3 % of the PIK3CA (H1047R) mutation in 86 CRC tissues, which was significantly higher than that discovered by DNA sequencing (9.3 %). A positive association between the PIK3CA (H1047R) mutation and the patients' age was first found, except for the negative relationship with the degree of tumor differentiation. In addition, the highly sensitive detection of a combinatorial mutation of PIK3CA, KRAS and BRAF was achieved using individual PCR-RFLP methods. CONCLUSIONS: We developed a sensitive, simple and rapid approach to detect the low-abundance PIK3CA (H1047R) mutation in real CRC specimens, providing an effective tool for guiding cancer targeted therapy.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias Colorretais/genética , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Fatores Etários , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Análise Mutacional de DNA/métodos , Feminino , Células HT29 , Humanos , Masculino , Pessoa de Meia-Idade
11.
J Pineal Res ; 58(4): 429-38, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25752481

RESUMO

Melatonin induces apoptosis in many different cancer cell lines, including colorectal cancer. However, the precise mechanisms involved remain largely unresolved. In this study, we provide evidence to reveal a new mechanism by which melatonin induces apoptosis of colorectal cancer LoVo cells. Melatonin at pharmacological concentrations significantly suppressed cell proliferation and induced apoptosis in a dose-dependent manner. The observed apoptosis was accompanied by the melatonin-induced dephosphorylation and nuclear import of histone deacetylase 4 (HDAC4). Pretreatment with a HDAC4-specific siRNA effectively attenuated the melatonin-induced apoptosis, indicating that nuclear localization of HDAC4 is required for melatonin-induced apoptosis. Moreover, constitutively active Ca(2+) /calmodulin-dependent protein kinase II alpha (CaMKIIα) abrogated the melatonin-induced HDAC4 nuclear import and apoptosis of LoVo cells. Furthermore, melatonin decreased H3 acetylation on bcl-2 promoter, leading to a reduction of bcl-2 expression, whereas constitutively active CaMKIIα(T286D) or HDAC4-specific siRNA abrogated the effect of melatonin. In conclusion, the present study provides evidence that melatonin-induced apoptosis in colorectal cancer LoVo cells largely depends on the nuclear import of HDAC4 and subsequent H3 deacetylation via the inactivation of CaMKIIα.


Assuntos
Apoptose/efeitos dos fármacos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Neoplasias Colorretais/metabolismo , Histona Desacetilases/metabolismo , Melatonina/farmacologia , Proteínas Repressoras/metabolismo , Acetilação/efeitos dos fármacos , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Humanos
12.
Zhonghua Yi Xue Za Zhi ; 95(6): 440-3, 2015 Feb 10.
Artigo em Zh | MEDLINE | ID: mdl-25916781

RESUMO

OBJECTIVE: To explore the efficacies and complications of Ahmed glaucoma valve implantation for treating refractory glaucoma. METHODS: A retrospective study of case series was conducted for 24 patients (26 eyes) with refractory glaucoma from February 2001 to July 2008 at our hospital. Ahmed glaucoma valve implantation was performed. Pre- and post-operative best spectacle-corrected visual acuity (BSCVA), intraocular pressure (IOP), number of medications and complications were recorded and analyzed. The follow-up period was 58-159 months. RESULTS: The post-operative values of IOP were 13.02+/-6.79, 11.43+/-5.24 and 18.56+/-6.43 mmHg at 1 day, 1 month and the last follow-up respectively. There were significant difference when compared with pre-operative IOP (37.59+/-10.76 mmHg, P < 0.01). And 65.38% of eyes maintained or gained ≥ 1 line of BSCVA. But there was no significant difference with pre-operative BSCVA (P = 0.110). Twenty eyes required anti-glaucoma drugs after glaucoma valve implantation and the average number of medication was 1.72+/-0.98. There was significant difference with the pre-operative medication number 2.7 ± 0.7 (P = 0.001). The surgical success rate was 73.1%. And the causes of failure were endophthalmitis, corneal endothelial decompensation, persistent conjunctival wound non-healing, glaucoma valve exposure and loss of light perception.Early postoperative complications were ocular hypotony, shallow anterior chamber, hyphema, transient high IOP and tube occlusion. And long-term complications included encapsulated cyst formation, tube exposure, corneal endothelial decompensation and endophthalmitis. CONCLUSIONS: Ahmed glaucoma valve implantation is efficacious for refractory glaucoma.However, clinicians should pay attention to the prevention and treatment of complications.


Assuntos
Glaucoma , Implantação de Prótese , Endoftalmite , Seguimentos , Implantes para Drenagem de Glaucoma , Humanos , Pressão Intraocular , Complicações Pós-Operatórias , Período Pós-Operatório , Estudos Retrospectivos , Tonometria Ocular , Resultado do Tratamento , Acuidade Visual
13.
ACS Appl Mater Interfaces ; 16(20): 26234-26244, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38711193

RESUMO

The huge volume expansion/contraction of silicon (Si) during the lithium (Li) insertion/extraction process, which can lead to cracking and pulverization, poses a substantial impediment to its practical implementation in lithium-ion batteries (LIBs). The development of low-strain Si-based composite materials is imperative to address the challenges associated with Si anodes. In this study, we have engineered a TiSi2 interface on the surface of Si particles via a high-temperature calcination process, followed by the introduction of an outermost carbon (C) shell, leading to the construction of a low-strain and highly stable Si@TiSi2@NC composite. The robust TiSi2 interface not only enhances electrical and ionic transport but also, more critically, significantly mitigates particle cracking by restraining the stress/strain induced by volumetric variations, thus alleviating pulverization during the lithiation/delithiation process. As a result, the as-fabricated Si@TiSi2@NC electrode exhibits a high initial reversible capacity (2172.7 mAh g-1 at 0.2 A g-1), superior rate performance (1198.4 mAh g-1 at 2.0 A g-1), and excellent long-term cycling stability (847.0 mAh g-1 after 1000 cycles at 2.0 A g-1). Upon pairing with LiNi0.6Co0.2Mn0.2O2 (NCM622), the assembled Si@TiSi2@NC||NCM622 pouch-type full cell exhibits exceptional cycling stability, retaining 90.1% of its capacity after 160 cycles at 0.5 C.

14.
Front Psychol ; 13: 920782, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795421

RESUMO

This study explores how the academic experience of executives affects green innovation. Using data on executive academic experience from a sample of Chinese listed companies, we explore the relationship between executive academic experience and green innovation using a combination of qualitative and quantitative methods. We find that executive academic experience has a positive impact on green innovation. We also investigate the moderating effect of managerial discretionary factors organizational slack, nature of property rights, and degree of market competition. The results show that organizational slack positively moderates the relationship between senior managers' academic experience and green innovation, and this positive relationship is more significant in state-owned enterprises. The degree of market competition had a negative moderating effect on the positive relationship between academic experience of senior managers and green innovation. Improved general competence and concern for the environment are two possible mechanisms by which senior managers' academic experience affects green innovation. Our findings suggest that academic experience of senior managers is an important factor for green innovation in emerging market firms.

15.
Polymers (Basel) ; 14(15)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35956554

RESUMO

Early diagnosis of metastatic colorectal cancer (mCRC) is extremely critical to improve treatment and extend survival. W3 is an aptamer that can specifically bind to mCRC cells with high affinity. Graphene oxide (GO) is a two-dimensional graphitic carbon nanomaterial, which has widely used in constructing biosensors. In this study, we have developed a no-wash fluorescent aptasensor for one-step and sensitive detection of mCRC LoVo cells. It is based on fluorescence resonance energy transfer (FRET) between GO and the W3 aptamer labeled with 5-carboxyfluorescein (FAM). GO can quench the green fluorescence of the FAM-labeled W3 (FAM-W3). In the presence of the target cells, FAM-W3 preferentially binds the target cells and detaches from the surface of GO, leading to the fluorescence of FAM recovery. It was demonstrated that the fluorescence recovery increases linearly in a wide range of 0~107 cells/mL (R2 = 0.99). The GO-based FAM-labeled W3 aptasensor (denoted as FAM-W3-GO) not only specifically recognizes mCRC cell lines (LoVo and HCT116), but also sensitively differentiates the target cells from mixed cells, even in the presence of only 5% of the target cells. Furthermore, FAM-W3-GO was applied to detect LoVo cells in human whole blood, which showed good reproducibility with an RSD range of 1.49% to 1.80%. Therefore, FAM-W3-GO may have great potential for early diagnosis of mCRC. This strategy of GO-based fluorescent aptasensor provides a simple, one-step, and highly sensitive approach for the detection of mCRC cells.

16.
ACS Appl Mater Interfaces ; 14(46): 51954-51964, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36350880

RESUMO

Silicon (Si) is regarded as one of the most promising anode materials for high-energy-density lithium (Li)-ion batteries (LIBs). However, Li insertion/extraction induced large volume change, which can lead to the fracture of the Si material itself and the delamination/pulverization of electrodes, is the major challenge for the practical application of Si-based anodes. Herein, a facile and scalable multilayer coating approach was proposed for the large-scale fabrication of functionally gradient Si/graphite (Si/Gr) composite electrodes to simultaneously mitigate the volume change-caused structural degradation and realize high capacity by regulating the spatial distributions of Si and Gr particles in the electrodes. Both our experimental characterizations and chemomechanical simulations indicated that, with a parabolic gradient (PG) distribution of Si through the thickness direction that the two Si-poor surface layers guarantee the major mechanical support and the middle Si-rich layer ensures the high capacity, the as-prepared PG-Si/Gr electrode can not only effectively improve the stability of the electrode structure but also efficiently enable high capacity and stable electrochemical reactions. Consequently, the PG-Si/Gr electrode with a mass loading of 3.15 mg cm-2 exhibited a reversible capacity of 579.2 mAh g-1 (1.82 mAh cm-2) after 200 cycles at 0.2C. Even with a mass loading of 8.45 mg cm-2, the PG-Si/Gr anodes still delivered a high reversible capacity of 4.04 mAh cm-2 after 100 cycles and maintained excellent cycling stability. Moreover, when paired with a commercial LiNi0.5Mn0.3Co0.2O2 (NCM532) cathode (9.56 mg cm-2), the PG-Si/Gr||NCM532 full cell revealed an initial reversible areal capacity of 1.64 mAh cm-2 and sustained a stable areal capacity of 0.94 mAh cm-2 at 0.2C after 100 cycles.

17.
Biosens Bioelectron ; 213: 114451, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35700603

RESUMO

Metastasis is a leading cause of cancer-related deaths. Hence, the discovery of more reliable metastasis-related biomarkers is crucial to improve the survival rate of cancer patients. W3 is an aptamer previously produced by the subtractive cell-SELEX using metastatic colorectal cancer cells as target cells and non-metastatic cells as negative cells. In this study, we aimed to evaluate whether the target molecule of W3 can potentially act as a metastatic biomarker. First, we obtained two cell subpopulations with different expression levels of the target molecule by W3-based cell sorting. Subsequently, we demonstrated that W3high cells have a higher metastatic potential than W3low cells both in vitro and in vivo. Further, immunohistochemical analysis revealed that W3 target expression is positively associated with metastasis and poor prognosis of CRC patients. Using mass spectrometry (MS) combined with pull-down, we identified that Ephrin type-A receptor 2 (EphA2) is the target of W3. EphA2's potential as a metastatic predictor was demonstrated by capturing W3-positive circulating tumor cells from CRC patients using a W3 probe. Based on these results, we put forward a stratagem for cell-SELEX-based biomarker discovery: selecting an aptamer through subtractive cell-SELEX towards the phenotype of interest; evaluating the functional phenotype of the target molecule by aptamer-based target cell sorting and analysis of clinical samples; and identifying the aptamer's target molecule using MS and aptamer-based target enrichment. This stratagem not only shortens the time for the clinical application of aptamers but also enables a more targeted and efficient discovery of biomarkers.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Neoplasias Colorretais , Aptâmeros de Nucleotídeos/química , Biomarcadores Tumorais/genética , Neoplasias Colorretais/diagnóstico , Humanos , Técnica de Seleção de Aptâmeros/métodos
18.
Technol Cancer Res Treat ; 19: 1533033820980074, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33308020

RESUMO

OBJECTIVE: We aimed to identify the expression of Sal-like 4 (SALL4) in breast cancer tissues and to explore the role of this gene in the carcinogenesis of breast cancer cells. METHODS: A total of 62 paired breast cancer and noncancerous tissue samples were obtained from patients with breast cancer. SALL4 expression patterns and their association with clinicopathological characteristics were investigated by qRT-PCR, western blotting, and immunochemistry in breast cancer tissues. After the knockdown of SALL4 by short hairpin RNAs (shRNAs), the proliferative, invasive, and apoptotic abilities of MDA-MB-435 and MDA-MB-468 cells (breast cancer cell lines) were measured by colony formation and CCK-8 assays, wound healing and transwell assays, and flow cytometry, respectively. RESULTS: SALL4 expression was higher in breast cancer tissues than that in the paired noncancerous tissues, and increased SALL4 expression in tumor tissues was closely related to tumor size and lymphatic metastasis. Furthermore, functional experiments revealed that SALL4 knockdown inhibited the cell proliferation, induced cell cycle arrest in G0/G1phase and apoptosis, and decreased the ability of migration and invasion in breast cancer cells. Additionally, our study first demonstrated that SALL4 played a critical role in modulating the tumorigenicity of breast cancer cells via the WNT/ß-catenin signaling pathway. CONCLUSIONS: Our results suggest that the expression of SALL4 is upregulated in breast cancer, and this upregulation is involved in the regulation of cell growth, invasion, and apoptosis. Hence, SALL4 may be a promising target for diagnosis and therapy in patients with breast cancer.


Assuntos
Apoptose/genética , Neoplasias da Mama/genética , Fatores de Transcrição/genética , Adulto , Idoso , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Células Cultivadas , Feminino , Expressão Gênica , Inativação Gênica , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Interferência de RNA , RNA Interferente Pequeno/genética
19.
Talanta ; 199: 634-642, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30952308

RESUMO

Gastric cancer (GC) is associated with high morbidity and mortality rates worldwide. Poorly differentiated GC predicts a poor prognosis and is related to patients' response to chemotherapy and targeted therapy. Therefore, it is very important to accurately evaluate the tumour differentiation status for the treatment of poorly differentiated GC. To develop a molecular probe to analyse poorly differentiated GC, we selected aptamers against poorly differentiated GC by subtractive Cell-SELEX using the poorly differentiated GC cell line BGC-823 as the target and the moderately differentiated GC cell line SGC-7901 as the negative control. After 15 rounds of selection, aptamer PDGC21 exhibited the highest affinity, and the Kd value of the truncated aptamer PDGC21-T was 35.2 ±â€¯1.1 nM. Aptamer PDGC21-T not only specifically bound to the target cells but also bound to other poorly differentiated GC cells. When combined with fluorescent nanoparticle quantum dots (QDs), the PDGC21-T-QD probe could distinguish poorly differentiated GC cells in mixed culture cells and clinical specimens. Furthermore, in a tissue microarray containing 15 cases from patients, there was a higher positive rate in GC tissues compared with adjacent normal tissues; in poorly differentiated tissues, in particular, the fluorescence signal was significantly higher than that in well/moderately differentiated tissues. Therefore, aptamer PDGC21-T holds great potential for use as a molecular imaging probe for the detection of poorly differentiated GC, which is of great significance for diagnosis and treatment.


Assuntos
Aptâmeros de Nucleotídeos/química , DNA de Cadeia Simples/química , Técnica de Seleção de Aptâmeros , Neoplasias Gástricas/diagnóstico por imagem , Diferenciação Celular , Citometria de Fluxo , Humanos , Microscopia de Fluorescência , Neoplasias Gástricas/patologia , Análise Serial de Tecidos , Células Tumorais Cultivadas
20.
Yi Chuan ; 30(2): 209-16, 2008 Feb.
Artigo em Zh | MEDLINE | ID: mdl-18244928

RESUMO

The amylose content of the mutant of autotetraploid indica rice D4063-1 is 5.23% anout, which was half of its origin diploid rice Minghui 63. The whole sequence of Waxy gene of D4063-1 was amplified and sequenced. A base was absent on the Wx of D4063-1 in exon sequence, which resulted in frameshift mutation and terminating codon occurred ahead in the 9 exon. The mutation of Wx also led to the change of some mutation in the 9 exon and terminating codon occurred early. The change of Wx also led to changes of the sites of common restriction endonuclease. The results showed that D4063-1 added two sph sites compared to indica and japonica rice; Compared to japonica rice, D4063-1decreased six Acc sites, and added 4 Xba, a Pst and a Sal restriction sites. Phylogenic analysis showed that the DNA sequence of Waxy gene of D4063-1 was closer to indica rice. We supposed that the Waxy gene of D4063-1 originated from genotype of Wxa. According to the differences of Wx in D4063-1, we deduced the absent base led to RNA splicing obstacle, which was the main cause of low amylose content and it might be related to the soft rice phenotype. Based on analysis of Wx of D4063-1, indica and japonica and according to the special sites of the three species, primers as markers-AUT4063-I were designed to distinguish D4063-1 from other rice. Combining with primer pair F5, dominant and codominant ways were established for discriminating them, and rapid and correct identification of D4063-1 from other rice could be done.


Assuntos
Marcadores Genéticos , Mutação , Oryza/classificação , Oryza/genética , Poliploidia , Amilose/metabolismo , Sequência de Bases , Éxons , Dados de Sequência Molecular , Oryza/metabolismo , Filogenia , RNA de Plantas/química , Alinhamento de Sequência , Análise de Sequência de DNA
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