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1.
Proc Natl Acad Sci U S A ; 121(19): e2315168121, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38683997

RESUMO

Accurate prediction of the efficacy of immunotherapy for cancer patients through the characterization of both genetic and phenotypic heterogeneity in individual patient cells holds great promise in informing targeted treatments, and ultimately in improving care pathways and clinical outcomes. Here, we describe the nanoplatform for interrogating living cell host-gene and (micro-)environment (NICHE) relationships, that integrates micro- and nanofluidics to enable highly efficient capture of circulating tumor cells (CTCs) from blood samples. The platform uses a unique nanopore-enhanced electrodelivery system that efficiently and rapidly integrates stable multichannel fluorescence probes into living CTCs for in situ quantification of target gene expression, while on-chip coculturing of CTCs with immune cells allows for the real-time correlative quantification of their phenotypic heterogeneities in response to immune checkpoint inhibitors (ICI). The NICHE microfluidic device provides a unique ability to perform both gene expression and phenotypic analysis on the same single cells in situ, allowing us to generate a predictive index for screening patients who could benefit from ICI. This index, which simultaneously integrates the heterogeneity of single cellular responses for both gene expression and phenotype, was validated by clinically tracing 80 non-small cell lung cancer patients, demonstrating significantly higher AUC (area under the curve) (0.906) than current clinical reference for immunotherapy prediction.


Assuntos
Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patologia , Células Neoplásicas Circulantes/metabolismo , Microfluídica/métodos , Análise de Célula Única/métodos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/sangue , Fenótipo , Linhagem Celular Tumoral , Imunoterapia/métodos , Perfilação da Expressão Gênica/métodos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/sangue , Técnicas Analíticas Microfluídicas/métodos , Técnicas Analíticas Microfluídicas/instrumentação
2.
FASEB J ; 38(5): e23519, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38457249

RESUMO

ARL3 is essential for cilia development, and mutations in ARL3 are closely associated with ciliopathies. In a previous study, we observed distinct phenotypes of retinal dystrophy in patients with heterozygous ARL3T31A and compound heterozygous ARL3T31A/C118F mutations, indicating that different mutation types may exert diverse effects on their functions. Here, we generated transformed immortal fibroblast cells from patients carrying heterozygous ARL3T31A and compound heterozygous ARL3T31A/C118F mutations, and systematically evaluated their cilia morphology and function, which were further validated in ARPE-19 cells. Results showed that both ARL3T31A and ARL3T31A/C118F mutations led to a decrease in cilium formation. The ARL3T31A/C118F mutations caused significantly elongated cilia and impaired retrograde transport, whereas the ARL3T31A mutation did not induce significant changes in fibroblasts. RNA-sequencing results indicated that compared to ARL3T31A , ARL3T31A/C118F fibroblasts exhibited a higher enrichment of biological processes related to neuron projection development, tissue morphogenesis, and extracellular matrix (ECM) organization, with noticeable alterations in pathways such as ECM-receptor interaction, focal adhesion, and TGF-ß signaling. Similar changes were observed in the proteomic results in ARPE-19 cells. Core regulated genes including IQUB, UNC13D, RAB3IP, and GRIP1 were specifically downregulated in the ARL3T31A/C118F group, and expressions of IQUB, NPM2, and SLC38A4 were further validated. Additionally, IQUB showed a rescuing effect on the overlong cilia observed in ARL3T31A/C118F fibroblasts. Our results not only enhance our understanding of ARL3-related diseases but also provide new insights into the analysis of heterozygous and compound heterozygous mutations in genetics.


Assuntos
Cílios , Proteômica , Humanos , Cílios/genética , Cílios/metabolismo , Transporte Proteico , Fatores de Ribosilação do ADP/genética , Fatores de Ribosilação do ADP/metabolismo , Mutação , Fibroblastos/metabolismo , Proteínas de Membrana/metabolismo
3.
BMC Public Health ; 24(1): 899, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532400

RESUMO

PURPOSE: To examine the knowledge, attitudes, and practices (KAP) of caregivers of children with Kawasaki disease toward Kawasaki disease. METHODS: This cross-sectional study was conducted at four hospitals in China from March 2023 to June 2023. The KAP scores were evaluated using a self-designed questionnaire (Cronbach's α = 0.840; KMO = 0.7381). Correlations between dimension scores were evaluated by Pearson correlation analysis. A structural equation model (SEM) was used to examine the relationships among factors. RESULTS: Of 643 surveyed, 49.50% were male caregivers. The mean knowledge, attitude, and practice scores were 7.12 ± 2.34 (possible range, 0-11), 29.23 ± 5.67 (possible range, 12-60), and 21.57 ± 5.34 (possible range, 6-30). Knowledge correlated with attitude (r = 0.172, P < 0.001) and practice (r = 0.280, P < 0.001). Attitude was significantly related to practice (r = 0.598, P < 0.001). SEM showed knowledge had a positive effect on attitudes (ß = 0.581, P < 0.001) and practices (ß = 0.786, P < 0.001). In addition, attitudes also positively affected practices (ß = 0.554, P < 0.001). Occupation type (ß = 0.598, P = 0.025) and monthly per capita income (ß=-0.750, P = 0.020) had different effects on attitudes, while monthly per capita income also had negative effects on practices (ß=-0.410, P = 0.021). CONCLUSION: Caregivers of children with Kawasaki disease have moderate knowledge and unfavorable attitudes but proactive practices toward this disease. The results could help design an educational intervention to improve KAP, which could translate into better patient management and outcomes. TRIAL REGISTRATION: Not applicable.


Assuntos
Cuidadores , Síndrome de Linfonodos Mucocutâneos , Criança , Humanos , Masculino , Feminino , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos e Questionários
4.
Luminescence ; 39(1): e4611, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37899383

RESUMO

Recently, lanthanide (Ln) luminescent nanocrystals have attracted increasing attention in various fields such as biomedical imaging, lasers, and anticounterfeiting. However, due to the forbidden 4f-4f transition of lanthanide ions, the absorption cross-section and luminescence brightness of lanthanide nanocrystals are limited. To address the challenge, we constructed an optical oscillator-like system to repeatedly simulate lanthanide nanocrystals to enhance the absorption efficiency of lanthanide ions on excitation photons. In this optical system, the upconversion luminescence (UCL) of Tm3+ emission of ~450 nm excited by a 980 nm laser can be amplified by a factor beyond 104 . The corresponding downshifting luminescence of Tm3+ at 1460 nm was enhanced by three orders of magnitude. We also demonstrated that the significant luminescence enhancement in the designed optical oscillator-like system was general for various lanthanide nanocrystals including NaYF4 :Yb3+ /Ln3+ , NaErF4 @NaYF4 and NaYF4 :Yb3+ /Ln3+ @NaYF4 :Yb3+ @NaYF4 (Ln = Er, Tm, Ho) regardless of the wavelengths of excitation sources (808 and 980 nm). The mechanism study revealed that both elevated laser power in the optical system and multiple excitations on lanthanide nanocrystals were the main reason for the luminescence amplification. Our findings may benefit the future development of low-threshold upconversion and downshifting luminescence of lanthanide nanocrystals and expand their applications.


Assuntos
Elementos da Série dos Lantanídeos , Nanopartículas , Elementos da Série dos Lantanídeos/química , Luminescência , Nanopartículas/química , Luz , Íons
5.
Molecules ; 28(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37175162

RESUMO

To efficiently eliminate highly polar organic pollutants from water has always been a difficult issue, especially in the case of ultralow concentrations. Herein, we present the facile synthesis of quinolinecarboxylic acid-linked COF (QCA-COF) via the Doebner multicomponent reaction, possessing multifunction, high specific surface area, robust physicochemical stability, and excellent crystallinity. The marked feature lies in the quinolinyl and carboxyl functions incorporated simultaneously to QCA-COF in one step. The major cis-orientation of carboxyl arms in QCA-COF was speculated by powder X-ray diffraction and total energy analysis. QCA-COF demonstrates excellent adsorption capacity for water-soluble organic pollutants such as rhodamine B (255.7 mg/g), methylene blue (306.1 mg/g), gentamycin (338.1 mg/g), and 2,4-dichlorophenoxyacetic acid (294.1 mg/g) in water. The kinetic adsorptions fit the pseudo-second order model and their adsorption isotherms are Langmuir model. Remarkably, QCA-COF can capture the above four water-soluble organic pollutants from real water samples at ppb level with higher than 95% removal efficiencies and excellent recycling performance.

6.
Angew Chem Int Ed Engl ; 62(49): e202311883, 2023 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-37860881

RESUMO

High-resolution in vivo optical multiplexing in second near-infrared window (NIR-II, 1000-1700 nm) is vital to biomedical research. Presently, limited by bio-tissue scattering, only luminescent probes located at NIR-IIb (1500-1700 nm) window can provide high-resolution in vivo multiplexed imaging. However, the number of available luminescent probes in this narrow NIR-IIb region is limited, which hampers the available multiplexed channels of in vivo imaging. To overcome the above challenges, through theoretical simulation we expanded the conventional NIR-IIb window to NIR-II long-wavelength (NIR-II-L, 1500-1900 nm) window on the basis of photon-scattering and water-absorption. We developed a series of novel lanthanide luminescent nanoprobes with emission wavelengths from 1852 nm to 2842 nm. NIR-II-L nanoprobes enabled high-resolution in vivo dynamic multiplexed imaging on blood vessels and intestines, and provided multi-channels imaging on lymph tubes, tumors and intestines. The proposed NIR-II-L probes without mutual interference are powerful tools for high-contrast in vivo multiplexed detection, which holds promise for revealing physiological process in living body.


Assuntos
Elementos da Série dos Lantanídeos , Nanopartículas , Neoplasias , Humanos , Elementos da Série dos Lantanídeos/química , Imagem Óptica/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Nanopartículas/química
7.
Microb Cell Fact ; 21(1): 144, 2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35842666

RESUMO

BACKGROUND: Filamentous fungi are highly efficient at deconstructing plant biomass by secreting a variety of enzymes, but the complex enzymatic regulation underlying this process is not conserved and remains unclear. RESULTS: In this study, cellulases and xylanases could specifically respond to Avicel- and xylan-induction, respectively, in lignocellulose-degrading strain Trichoderma guizhouense NJAU4742, however, the differentially regulated cellulases and xylanases were both under the absolute control of the same TgXyr1-mediated pathway. Further analysis showed that Avicel could specifically induce cellulase expression, which supported the existence of an unknown specific regulator of cellulases in strain NJAU4742. The xylanase secretion is very complex, GH10 endoxylanases could only be induced by Avicel, while, other major xylanases were significantly induced by both Avicel and xylan. For GH10 xylanases, an unknown specific regulator was also deduced to exist. Meanwhile, the post-transcriptional inhibition was subsequently suggested to stop the Avicel-induced xylanases secretion, which explained the specifically high xylanase activities when induced by xylan in strain NJAU4742. Additionally, an economical strategy used by strain NJAU4742 was proposed to sense the environmental lignocellulose under the carbon starvation condition, that only slightly activating 4 lignocellulose-degrading genes before largely secreting all 33 TgXyr1-controlled lignocellulases if confirming the existence of lignocellulose components. CONCLUSIONS: This study, aiming to explore the unknown mechanisms of plant biomass-degrading enzymes regulation through the combined omics analysis, will open directions for in-depth understanding the complex carbon utilization in filamentous fungi.


Assuntos
Celulases , Hypocreales , Trichoderma , Carbono/metabolismo , Celulases/genética , Celulases/metabolismo , Celulose/metabolismo , Hypocreales/genética , Hypocreales/metabolismo , Trichoderma/genética , Trichoderma/metabolismo , Xilanos/metabolismo
8.
Nucleic Acids Res ; 48(5): 2733-2748, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32009146

RESUMO

Family with sequence similarity (FAM46) proteins are newly identified metazoan-specific poly(A) polymerases (PAPs). Although predicted as Gld-2-like eukaryotic non-canonical PAPs, the detailed architecture of FAM46 proteins is still unclear. Exact biological functions for most of FAM46 proteins also remain largely unknown. Here, we report the first crystal structure of a FAM46 protein, FAM46B. FAM46B is composed of a prominently larger N-terminal catalytic domain as compared to known eukaryotic PAPs, and a C-terminal helical domain. FAM46B resembles prokaryotic PAP/CCA-adding enzymes in overall folding as well as certain inter-domain connections, which distinguishes FAM46B from other eukaryotic non-canonical PAPs. Biochemical analysis reveals that FAM46B is an active PAP, and prefers adenosine-rich substrate RNAs. FAM46B is uniquely and highly expressed in human pre-implantation embryos and pluripotent stem cells, but sharply down-regulated following differentiation. FAM46B is localized to both cell nucleus and cytosol, and is indispensable for the viability of human embryonic stem cells. Knock-out of FAM46B is lethal. Knock-down of FAM46B induces apoptosis and restricts protein synthesis. The identification of the bacterial-like FAM46B, as a pluripotent stem cell-specific PAP involved in the maintenance of translational efficiency, provides important clues for further functional studies of this PAP in the early embryonic development of high eukaryotes.


Assuntos
Células-Tronco Embrionárias Humanas/metabolismo , Nucleotidiltransferases/metabolismo , Polinucleotídeo Adenililtransferase/metabolismo , Células Procarióticas/metabolismo , Animais , Biocatálise , Linhagem Celular , Sobrevivência Celular , Desenvolvimento Embrionário , Humanos , Modelos Moleculares , Nucleotidiltransferases/química , Nucleotidiltransferases/genética , Polinucleotídeo Adenililtransferase/química , Ligação Proteica , Domínios Proteicos , RNA/metabolismo , Especificidade por Substrato , Xenopus
9.
BMC Musculoskelet Disord ; 23(1): 514, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35637468

RESUMO

OBJECTIVE: Cancer-induced bone pain (CIBP) is a kind of pain with complex pathophysiology. Proteinase-activated receptor 2 (PAR-2) is involved in CIBP. This study explored the effects of PAR-2 on CIBP rats. METHODS: CIBP rat model was established by injecting Walker 256 rat breast cancer cells into the left tibia of female Sprague-Dawley rats and verified by tibial morphology observation, HE staining, and mechanical hyperalgesia assay. CIBP rats were injected with PAR-2 inhibitor, ERK activator, and CREB inhibitor through the spinal cord sheath on the 13th day after operation. CIBP behaviors were measured by mechanical hyperalgesia assay. On the 14th day after operation, L4-5 spinal cord tissues were obtained. PAR-2 expression, co-expression of PAR-2 and astrocyte marker GFAP, GFAP mRNA and protein levels and the ERK pathway-related protein levels were detected by Western blot, immunofluorescence double staining, RT-qPCR, and Western blot. RESULTS: CIBP rats had obvious mechanical hyperalgesia and thermal hyperalgesia from the 7th day after modeling; mechanical hyperalgesia threshold and thermal threshold were decreased; PAR-2 was increased in spinal cord tissues and was co-expressed with GFAP. PAR-2 silencing alleviated rat CIBP by inhibiting astrocyte activation. p-ERK/t-ERK and p-CREB/t-CREB levels in CIBP spinal cord were elevated, the ERK/CREB pathway was activated, while the ERK/CREB pathway was inhibited by PAR-2 silencing. The alleviating effect of PAR-2 inhibitor on hyperalgesia behaviors in CIBP rats were weakened by ERK activator, while were partially restored by CREB inhibitor. CONCLUSIONS: PAR-2 knockdown inhibited the ERK/CREB pathway activation and astrocyte activation, thus alleviating CIBP in rats.


Assuntos
Dor do Câncer , Neoplasias , Animais , Feminino , Humanos , Ratos , Astrócitos/metabolismo , Dor do Câncer/etiologia , Dor do Câncer/metabolismo , Hiperalgesia/tratamento farmacológico , Hiperalgesia/etiologia , Sistema de Sinalização das MAP Quinases , Dor/tratamento farmacológico , Dor/etiologia , Ratos Sprague-Dawley
10.
Chem Soc Rev ; 48(3): 850-884, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30565609

RESUMO

Barcode technology can deliver batched information for patient healthcare. For clinical examinations, barcodes serve as reporters for labeling multiple targets, and meanwhile, facilitate improved sensitivity and specificity, thus enabling barcode as a promising alternative to traditional labels for biomarker identification and signal amplification. However, faced with the stringent claims of point-of-care (POC) bioassays, efforts are needed to advance current technologies toward rapidity, robustness, affordability, and user-friendliness. In the past decades, chemists have succeeded in delicate fabrication of the barcode libraries for encoding. Nevertheless, the decoding technologies remain poorly discussed, especially simplified decoding strategies for POC bioassays. Recent emergence of portable cartridges and miniaturized signal-recording devices has brought a promise to merge barcodes-assisted bioassay with POC testing (POCT). This review provides a comprehensive summary on barcode encoding and decoding, with emphasis on their potential use in POCT, facilitated by improved manufacturing and portable devices. Future directions of barcoded bioassays for POCT and current challenges are also presented. We anticipate that this review will be beneficial to promoting barcodes toward broad applications.


Assuntos
Bioensaio/instrumentação , Bioensaio/métodos , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Sistemas Automatizados de Assistência Junto ao Leito/tendências , Animais , Corantes Fluorescentes/química , Humanos , Aplicativos Móveis/tendências , Imagem Óptica/métodos , Medicina de Precisão/métodos , Nanomedicina Teranóstica/métodos
11.
Anal Chem ; 91(10): 6754-6760, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31006238

RESUMO

Fluorescent organic nanoparticles (FONs) are promising alternatives for biological imaging applications owing to the increasing concerns over the potential toxicity and poor degradability of inorganic particles-based probes. However, synthesis of stable, small-sized FONs in aqueous media remains challenging. Inspired by the self-polymerization chemistry of phenolic compounds, we demonstrate ultrafast synthesis of FONs (phenolic compound-derived FONs, PhFONs) from a variety of molecular building blocks including dopamine, norepinephrine, pyrogallol, and gallic acid, simply by nontherml plasma treatment at the aqueous interface. Specifically, using dopamine as the precursor, poly(dopamine) (PD)-FONs featuring a small size of 3 nm are obtained within 1 min. Compositional and structural characterizations confirm the polymeric architectures in PD-FONs. The PhFONs, with multicolor emissions, excellent biocompatibility, high stability, and size-dependent access into cell nucleus, are suitable for live cell imaging and developing nucleus-targeting imaging platforms.


Assuntos
Corantes Fluorescentes/química , Nanopartículas/química , Fenóis/química , Gases em Plasma/química , Polímeros/química , Animais , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/toxicidade , Camundongos , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Células NIH 3T3 , Nanopartículas/toxicidade , Fenóis/toxicidade , Polímeros/síntese química , Polímeros/toxicidade
12.
Adv Exp Med Biol ; 1185: 347-352, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31884636

RESUMO

To investigate whether intravitreal injection of amyloid ß1-42 (Aß1-42) activates the complement system and induces retinal inflammatory responses and malfunction, Aß1-42 was applied intravitreally in mice. The expressions of key components of complement system were determined by real-time PCR. Retinal function was assessed by electroretinography. We found interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in Aß1-42 treated mice retinas increased from day 1 to day 7. Compared with control group, mRNA expression of C1qa and C3 in the Aß1-42 treated retinas increased at days 1 and 7. The level of CFB, CFD, or CFH increased at day 4 and day 7. Regulator of membrane attack complex (MAC), CD59a, increased from day 1 to day 7. The expression of the main complement components in Aß1-42 treated eyes increased at days 4 and 7. Therefore, our results suggested that exogenous Aß1-42 activated CP and AP of the complement system in mice retinas, induced retinal inflammatory responses, and caused retinal malfunction.


Assuntos
Peptídeos beta-Amiloides/administração & dosagem , Proteínas do Sistema Complemento/imunologia , Inflamação/imunologia , Fragmentos de Peptídeos/administração & dosagem , Retina/fisiopatologia , Animais , Antígenos CD59/imunologia , Complexo de Ataque à Membrana do Sistema Complemento/imunologia , Eletrorretinografia , Interleucina-6/imunologia , Injeções Intravítreas , Camundongos , Retina/imunologia , Fator de Necrose Tumoral alfa/imunologia
13.
Anal Chem ; 90(15): 9132-9137, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-30004664

RESUMO

Immunoassays whose readouts rely on chemiluminescence are increasingly useful for a broad range of analytical applications, but they are rarely made into point-of-care (POC) format because of the complex reagents required (some reagents have to be stored in low temperatures, and some reagents have to be freshly made right before the assay). This study reports a self-contained chemiluminescent lateral flow assay (CLFA), which prestores all necessary reagents. This CLFA contains three parts: the normal lateral flow assay (LFA) strip, the chemiluminescence substrate pad, and the polycarbonate (PC) holder. On the LFA strip, we simultaneously labeled horseradish peroxidase (HRP) and antibody on the gold nanoparticles (AuNPs) for the conjugate pad. For the substrate pad, we used sodium perborate as the oxidant and lyophilized the chemiluminescence substrate on the glass fiber, which allows long-term storage. After the transfer of substrate from the substrate pad to the nitrocellulose (NC) membrane, we captured the chemiluminescence signal for the quantification of the targets. The HRP on the AuNPs can amplify the chemiluminescence signal efficiently. We used this CLFA system to detect both macromolecules and small molecules successfully. This self-contained and easily processable device is exceedingly appropriate for rapid detection and is a convenient platform for POC testing.


Assuntos
Técnicas Biossensoriais/instrumentação , Ácido Fólico/análise , Medições Luminescentes/instrumentação , Testes Imediatos , alfa-Fetoproteínas/análise , Anticorpos Imobilizados/química , Colódio/química , Desenho de Equipamento , Ouro/química , Peroxidase do Rábano Silvestre/química , Humanos , Imunoensaio/instrumentação , Nanopartículas Metálicas/química , Substitutos do Leite/química , Fitas Reagentes/análise
14.
Small ; 14(7)2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29265567

RESUMO

The degradation of intervertebral discs (IVD), a typical hierarchical structured tissue, causes serious neck and back pain. The current methods cannot fully reconstitute the unique structure and function of native IVD. In this study, by reverse reconstruction of the structure of native IVD and bioprinting bacterial cellulose (BC) nanofibers with a high-throughput optimized micropattern screening microchip, a total IVD is created that contained type II collagen-based nucleus pulposus (NP) and hierarchically organized and micropatterned BC-based annulus fibrosus (AF), mimicking native IVD tissue. The artificial NP contains rat NP cells, whereas the AF contains concentrically arranged BC layers with aligned micropatterns and attached AF cells in +/-30° alternate directions between adjacent layers. Long-term (3 months) implantation experiments on rats demonstrate the excellent structural (shape maintenance, hydration, tissue integration) and functional (mechanical support and flexibility) performance of the artificial IVD. This study provides a novel strategy for creating highly sophisticated artificial tissues.


Assuntos
Bioimpressão/métodos , Celulose/química , Disco Intervertebral , Animais , Núcleo Pulposo/química , Ratos , Engenharia Tecidual/métodos
15.
Phys Chem Chem Phys ; 19(28): 18167-18171, 2017 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-28692090

RESUMO

Our work investigates the effect of an external magnetic field on different dealloying stages of the formation of a nanoporous magnetic material. The magnetic field first prolongs the Ni rearrangement process at a low magnetic flux density, whereas the trend is reversed and the Ni rearrangement process is shortened at a higher magnetic flux density. The much finer morphology of nanoporous Ni can be prepared by adjusting the external magnetic flux density.

16.
Appl Opt ; 55(31): 8732-8737, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27828268

RESUMO

Three InGaAs photocathode samples with different emission layers were prepared using metal organic chemical vapor deposition and activated by Cs, O. The spectral responsivity curves of the three samples were obtained, and the quantum efficiency formula of the InGaAs photocathodes with multi-sublayers was derived. Results show that the InGaAs samples with thick emission layers have higher spectral responsivity, and the wavelength of the threshold decreases with the decrease of the In component. According to the performance parameters obtained by fitting the quantum efficiency of the experiment, it was found that a higher In component corresponds to a lower electron escape probability. Therefore, it is difficult to prepare InGaAs photocathodes with a high electron escape probability and a long threshold wavelength at the same time. By adding mini transition layers between the sublayers, the interface recombination velocity decreases, and the critical thickness of the sublayers increases. In conclusion, mini transition layers are very important for the preparation of InGaAs photocathodes capable of high performance.

17.
Biosensors (Basel) ; 14(6)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38920583

RESUMO

As a typical biomarker of Alzheimer's disease, rapid and specific detection of tau protein can help improve the early diagnosis and prognosis of the disease. In this study, a simple sandwich electrochemical immunosensor was developed for rapid detection of tau protein. Primary monoclonal antibodies (mAb1) against the middle domain of tau protein (amino acids 189-195) were immobilized on the gold electrode surface through a self-assembled monolayer (SAM) of 3,3'-dithiobis (sulfosuccinimidyl propionate) (DTSSP). Then the tau protein was captured through the specific adsorption between the antigen and the antibody, resulting in a change in the impedance. Secondary monoclonal antibodies (mAb2) against the N-terminal region of tau protein were used for further amplification of the binding reaction between mAb1 and tau protein. A linear correlation between the total change in impedance and the logarithm of tau concentration was found from 2 × 10-6 mg mL-1 to 2 × 10-3 mg mL-1, with a detection limit as low as 1 × 10-6 mg mL-1. No significant interference was observed from human serum albumin. Furthermore, the fabricated sandwich immunosensor successfully detected target tau protein in artificial cerebrospinal fluid (aCSF) samples, indicating good potential for clinical applications in the future.


Assuntos
Doença de Alzheimer , Biomarcadores , Técnicas Biossensoriais , Técnicas Eletroquímicas , Proteínas tau , Doença de Alzheimer/diagnóstico , Humanos , Anticorpos Monoclonais , Ouro/química , Imunoensaio/métodos , Limite de Detecção , Eletrodos
18.
Genome Biol ; 25(1): 122, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741214

RESUMO

BACKGROUND: Pluripotent states of embryonic stem cells (ESCs) with distinct transcriptional profiles affect ESC differentiative capacity and therapeutic potential. Although single-cell RNA sequencing has revealed additional subpopulations and specific features of naive and primed human pluripotent stem cells (hPSCs), the underlying mechanisms that regulate their specific transcription and that control their pluripotent states remain elusive. RESULTS: By single-cell analysis of high-resolution, three-dimensional (3D) genomic structure, we herein demonstrate that remodeling of genomic structure is highly associated with the pluripotent states of human ESCs (hESCs). The naive pluripotent state is featured with specialized 3D genomic structures and clear chromatin compartmentalization that is distinct from the primed state. The naive pluripotent state is achieved by remodeling the active euchromatin compartment and reducing chromatin interactions at the nuclear center. This unique genomic organization is linked to enhanced chromatin accessibility on enhancers and elevated expression levels of naive pluripotent genes localized to this region. In contradistinction, the primed state exhibits intermingled genomic organization. Moreover, active euchromatin and primed pluripotent genes are distributed at the nuclear periphery, while repressive heterochromatin is densely concentrated at the nuclear center, reducing chromatin accessibility and the transcription of naive genes. CONCLUSIONS: Our data provide insights into the chromatin structure of ESCs in their naive and primed states, and we identify specific patterns of modifications in transcription and chromatin structure that might explain the genes that are differentially expressed between naive and primed hESCs. Thus, the inversion or relocation of heterochromatin to euchromatin via compartmentalization is related to the regulation of chromatin accessibility, thereby defining pluripotent states and cellular identity.


Assuntos
Células-Tronco Pluripotentes , Análise de Célula Única , Humanos , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/citologia , Genoma Humano , Eucromatina/genética , Eucromatina/metabolismo , Cromatina/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Embrionárias Humanas/citologia , Heterocromatina/metabolismo , Células-Tronco Embrionárias/metabolismo , Montagem e Desmontagem da Cromatina
19.
J Chromatogr A ; 1713: 464520, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-37995545

RESUMO

Aflatoxins (AFs) exhibit hepatotoxicity, immunotoxicity, and carcinogenicity, and their detection in food has attracted widespread concern. An ordered macroporous metal-organic framework (OM-ZIF-8) based on solid-phase extraction (SPE) was used to extract six AFs from milk products. The SPE conditions, including eluting solvent, eluting volume, amounts of OM-ZIF-8, pH of loading solution, loading solvent, ionic strength, loading flow rate, and elution flow rate, were exhaustively optimized. Under optimal parameters, the six AFs were detected by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The OM-ZIF-8 exhibited satisfactory AFs extraction performance through ordered macropore structure, π-π interaction, coordination interaction, and electrostatic interaction. Furthermore, linearity in the range of 0.01-100 ng mL-1 with low detection limits of 0.002-0.0150 ng mL-1 was obtained, and the relative recoveries of AFs were 80.3-110 % with relative standard deviation ≤8.7 %. Thus, this research provides a promising platform for the analysis of trace AFs in complex foods.


Assuntos
Aflatoxinas , Estruturas Metalorgânicas , Animais , Leite/química , Aflatoxinas/análise , Espectrometria de Massas em Tandem/métodos , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Solventes/análise
20.
Front Psychiatry ; 15: 1392958, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38751414

RESUMO

Background: Pediatric cerebral palsy (CP) is a non-progressive brain injury syndrome characterized by central motor dysfunction and insufficient brain coordination ability. The etiology of CP is complex and often accompanied by diverse complications such as intellectual disability and language disorders, making clinical treatment difficult. Despite the availability of pharmacological interventions, rehabilitation programs, and spasticity relief surgery as treatment options for CP, their effectiveness is still constrained. Electroacupuncture (EA) stimulation has demonstrated great improvements in motor function, but its comprehensive, objective therapeutic effects on pediatric CP remain to be clarified. Methods: We present a case of a 5-year-old Chinese female child who was diagnosed with CP at the age of 4. The patient exhibited severe impairments in motor, language, social, and cognitive functions. We performed a 3-month period of EA rehabilitation, obtaining resting state functional magnetic resonance imaging (rs-fMRI) of the patient at 0 month, 3 months and 5 months since treatment started, then characterized brain functional connectivity patterns in each phase for comparison. Results: After a 12-month follow-up, notable advancements were observed in the patient's language and social symptoms. Changes of functional connectivity patterns confirmed this therapeutic effect and showed specific benefits for different recovery phase: starting from language functions then modulating social participation and other developmental behaviors. Conclusion: This is a pioneering report demonstrating the longitudinal effect of EA stimulation on functional brain connectivity in CP patients, suggesting EA an effective intervention for developmental disabilities (especially language and social dysfunctions) associated with pediatric CP.

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