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1.
Cell ; 180(4): 764-779.e20, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32059779

RESUMO

The heterogeneity of endothelial cells (ECs) across tissues remains incompletely inventoried. We constructed an atlas of >32,000 single-EC transcriptomes from 11 mouse tissues and identified 78 EC subclusters, including Aqp7+ intestinal capillaries and angiogenic ECs in healthy tissues. ECs from brain/testis, liver/spleen, small intestine/colon, and skeletal muscle/heart pairwise expressed partially overlapping marker genes. Arterial, venous, and lymphatic ECs shared more markers in more tissues than did heterogeneous capillary ECs. ECs from different vascular beds (arteries, capillaries, veins, lymphatics) exhibited transcriptome similarity across tissues, but the tissue (rather than the vessel) type contributed to the EC heterogeneity. Metabolic transcriptome analysis revealed a similar tissue-grouping phenomenon of ECs and heterogeneous metabolic gene signatures in ECs between tissues and between vascular beds within a single tissue in a tissue-type-dependent pattern. The EC atlas taxonomy enabled identification of EC subclusters in public scRNA-seq datasets and provides a powerful discovery tool and resource value.


Assuntos
Células Endoteliais/metabolismo , Análise de Célula Única , Transcriptoma , Animais , Encéfalo/citologia , Sistema Cardiovascular/citologia , Células Endoteliais/classificação , Células Endoteliais/citologia , Trato Gastrointestinal/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculos/citologia , Especificidade de Órgãos , RNA-Seq , Testículo/citologia
2.
FASEB J ; 38(7): e23554, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38588175

RESUMO

Bones can form the scaffolding of the body, support the organism, coordinate somatic movements, and control mineral homeostasis and hematopoiesis. The immune system plays immune supervisory, defensive, and regulatory roles in the organism, which mainly consists of immune organs (spleen, bone marrow, tonsils, lymph nodes, etc.), immune cells (granulocytes, platelets, lymphocytes, etc.), and immune molecules (immune factors, interferons, interleukins, tumor necrosis factors, etc.). Bone and the immune system have long been considered two distinct fields of study, and the bone marrow, as a shared microenvironment between the bone and the immune system, closely links the two. Osteoimmunology organically combines bone and the immune system, elucidates the role of the immune system in bone, and creatively emphasizes its interdisciplinary characteristics and the function of immune cells and factors in maintaining bone homeostasis, providing new perspectives for skeletal-related field research. In recent years, bone immunology has gradually become a hot spot in the study of bone-related diseases. As a new branch of immunology, bone immunology emphasizes that the immune system can directly or indirectly affect bones through the RANKL/RANK/OPG signaling pathway, IL family, TNF-α, TGF-ß, and IFN-γ. These effects are of great significance for understanding inflammatory bone loss caused by various autoimmune or infectious diseases. In addition, as an external environment that plays an important role in immunity and bone, this study pays attention to the role of exercise-mediated bone immunity in bone reconstruction.


Assuntos
Osso e Ossos , Osteoclastos , Osteoclastos/metabolismo , Osso e Ossos/metabolismo , Remodelação Óssea , Transdução de Sinais , Sistema Imunitário , Ligante RANK/metabolismo
3.
J Cell Mol Med ; 28(8): e18300, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38613348

RESUMO

The Hippo signalling pathway, an evolutionarily conserved kinase cascade, has been shown to be crucial for cell fate determination, homeostasis and tissue regeneration. Recent experimental and clinical studies have demonstrated that the Hippo signalling pathway is involved in the pathophysiology of ocular diseases. This article provides the first systematic review of studies on the regulatory and functional roles of mammalian Hippo signalling systems in eye diseases. More comprehensive studies on this pathway are required for a better understanding of the pathophysiology of eye diseases and the development of effective therapies.


Assuntos
Oftalmopatias , Animais , Diferenciação Celular , Via de Sinalização Hippo , Homeostase , Mamíferos
4.
J Cell Physiol ; 238(6): 1193-1206, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37120830

RESUMO

White adipose tissue (WAT) is not only an energy storage reservoir that is critical in energy homeostasis but is also a highly metabolically active endocrine organ. WAT can secrete a variety of adipocytokines, including leptin (LEP), adiponectin (APN), resistin, visfatin, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and osteopontin (OPN). It can also synthesize and secrete exosomes, which enhance intercellular communication and participate in various physiological processes in the body. It can also synthesize and secrete exosomes to enhance intercellular communication and participate in a variety of physiological processes in the body. The skeleton is an important organ for protecting internal organs. It forms the scaffolding of the body and gives the body its basic form. It drives muscle contraction to produce movement under the regulation of the nervous system. It is also an important hematopoietic organ; and it is regulated by the cytokines secreted by WAT. As research related to the release of adipocytokines from WAT to affect the skeleton continues to progress, an inextricable link between bone lipid regulation has been identified. In this paper, we review the literature to summarize the structure, function and metabolism of WAT, elaborate the specific molecular mechanisms by which WAT-secreted hormones, cytokines and exosomes regulate skeletal cells, provide a theoretical basis for the in-depth study of WAT cross-organ regulation of bone, and provide new ideas for finding new adipose-secreted targeting factors for the treatment of skeletal diseases.


Assuntos
Tecido Adiposo Branco , Osso e Ossos , Adipocinas/metabolismo , Adiponectina/metabolismo , Tecido Adiposo Branco/metabolismo , Citocinas/metabolismo , Homeostase , Leptina/metabolismo , Osso e Ossos/metabolismo
5.
Diam Relat Mater ; 134: 109775, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36819598

RESUMO

In this study, we introduced H-terminated diamond solution-gate field-effect transistor (H-diamond SGFET) to detect trace SARS-CoV-2 N-protein, which plays an important role in replication and transcription of viral RNA. 1-Pyrenebutyric acid-N-hydroxy succinimide ester (Pyr-NHS) was modified on H-diamond surface as linker, on which the specific antibody of SARS-CoV-2 N-protein was catenated. Fourier transform infrared spectrum, scanning electron microscope and energy dispersive spectrum were utilized to demonstrate the modification of H-diamond with Pyr-NHS and antibody. Shifts of IDS(max) at VGS = -500 mV in transfer characteristics of H-diamond SGFET was observed to determine N-protein concentration in phosphate buffer solution. Good linear relationship between IDS(max) and log10(N-protein) was observed from 10-14 to 10-5 g/mL with goodness of fit R2 = 0.90 and sensitivity of 1.98 µA/Log10 [concentration of N-protein] at VDS = -500 mV, VGS = -500 mV. Consequently, this prepared H-diamond SGFET biosensor may provide a new idea for diagnosis of SARS-CoV-2 due to a wide detection range from 10-14 to 10-5 g/mL and low limit of detection 10-14 g/mL.

6.
Molecules ; 28(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38138468

RESUMO

A large quantity of coal fly ash is generated worldwide from thermal power plants, causing a serious environmental threat owing to disposal and storage problems. In this work, for the first time, coal fly ash is converted into advanced and novel aerogel fibers and high-purity α-Al2O3. Silica-bacterial cellulose composite aerogel fibers (CAFs) were synthesized using an in situ sol-gel process under ambient pressure drying. Due to the unique "nanoscale interpenetrating network" (IPN) structure, the CAFs showed wonderful mechanical properties with an optimum tensile strength of 5.0 MPa at an ultimate elongation of 5.8%. Furthermore, CAFs with a high porosity (91.8%) and high specific surface area (588.75 m2/g) can inherit advanced features, including excellent thermal insulation, stability over a wide temperature range, and hydrophobicity (contact angle of approximately 144°). Additionally, Al2O3 was simultaneously extracted from the coal fly ash to ensure that the coal fly ash was fully exploited. Overall, low-cost woven CAFs fabrics are suitable for wearable applications and offer a great approach to comprehensively use coal fly ash to address environmental threats.

7.
J Sep Sci ; 44(18): 3429-3440, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34313005

RESUMO

A novel nanodisc-based immobilization method was developed for high-efficient purification and reconstitution of cytochrome P450 in one step. Using membrane scaffold protein containing a histidine tag, charged-nanodiscs were prepared in the form of self-assembly of lipid-protein nanoparticles. Their properties including the particle diameter and its distribution and Zeta potential were controlled well by adjusting molar ratios of phospholipids to membrane scaffold protein. At an optimum lipid-to-membrane scaffold protein molar ratio of 60:1, uniformly regular-shaped and discoidal nanodiscs with an average particle diameter of 10 nm and Zeta potential of -19 mV were obtained. They can be well fractionated by size exclusion chromatography. Charged-nanodiscs were successfully immobilized onto Ni-chelating microspheres via histidine tags with a density of 6.6 mg membrane scaffold protein/mL gel. After being packed in a column, chromatography studies demonstrated that this nanodisc-immobilized chromatographic medium had a specific binding to cytochrome P450 in rat liver microsome. Nanodiscs containing cytochrome P450 can be furthermore eluted from the column with a diameter of about 87.0 nm and height of about 8.0 nm, respectively. The purity of cytochrome P450 after purification increased 25 folds strikingly. This nanodisc-immobilized chromatography method is promising for the one-step purification and reconstitution of membrane protein.


Assuntos
Sistema Enzimático do Citocromo P-450/análise , Sistema Enzimático do Citocromo P-450/isolamento & purificação , Proteínas Imobilizadas/química , Proteínas de Membrana/química , Nanoestruturas/química , Animais , Cromatografia Líquida , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas Imobilizadas/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Microssomos Hepáticos/metabolismo , Ratos , Ratos Sprague-Dawley
8.
Proc Natl Acad Sci U S A ; 115(41): 10351-10356, 2018 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-30249667

RESUMO

VEGF-B was discovered a long time ago. However, unlike VEGF-A, whose function has been extensively studied, the function of VEGF-B and the mechanisms involved still remain poorly understood. Notwithstanding, drugs that inhibit VEGF-B and other VEGF family members have been used to treat patients with neovascular diseases. It is therefore critical to have a better understanding of VEGF-B function and the underlying mechanisms. Here, using comprehensive methods and models, we have identified VEGF-B as a potent antioxidant. Loss of Vegf-b by gene deletion leads to retinal degeneration in mice, and treatment with VEGF-B rescues retinal cells from death in a retinitis pigmentosa model. Mechanistically, we demonstrate that VEGF-B up-regulates numerous key antioxidative genes, particularly, Gpx1 Loss of Gpx1 activity largely diminished the antioxidative effect of VEGF-B, demonstrating that Gpx1 is at least one of the critical downstream effectors of VEGF-B. In addition, we found that the antioxidant function of VEGF-B is mediated mainly by VEGFR1. Given that oxidative stress is a crucial factor in numerous human diseases, VEGF-B may have therapeutic value for the treatment of such diseases.


Assuntos
Antioxidantes/metabolismo , Degeneração Retiniana/genética , Fator B de Crescimento do Endotélio Vascular/metabolismo , Animais , Anticorpos Neutralizantes/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica , Glutationa Peroxidase/genética , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Estresse Oxidativo , Retina/efeitos dos fármacos , Retina/patologia , Degeneração Retiniana/tratamento farmacológico , Retinose Pigmentar/genética , Fator B de Crescimento do Endotélio Vascular/genética , Fator B de Crescimento do Endotélio Vascular/farmacologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Glutationa Peroxidase GPX1
9.
Hong Kong Physiother J ; 41(2): 119-125, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34177200

RESUMO

BACKGROUND: Since the outbreak of the SARS-CoV-2 virus in December 2019, the COVID-19 pandemic continues to threaten global stability. Transmission of SARS-CoV-2 is mostly by respiratory droplets and direct contact but viral RNA fragments have also been detected in the faecal waste of patients with COVID-19. Cleanliness and effective sanitation of public toilets is a concern, as flushing the toilet is potentially an aerosol generating procedure. When the toilets are of the squatting type and without a cover, there exists a risk of viral contamination through the splashing of toilet water and aerosol generation. OBJECTIVE: This study aims to determine whether the cleanliness of public toilets was a concern to the general population during the COVID-19 pandemic, and whether a squatting toilet was preferred to a seated design. METHODS: A questionnaire was designed and posted on "WeChat" contact groups of the investigators. RESULTS: The survey showed that 91% of participants preferred squatting toilets, but that 72% were apprehensive of personal contamination when using public toilets. Over 63% of the respondents had encountered an incidence of water splash and would prefer public toilets to be covered during flushing and 83% of these respondents preferred a foot-controlled device. CONCLUSION: This survey suggests that consideration should be given to the installation of a simple foot-controlled device to cover public squatting toilets to help restrict potential COVID-19 contamination and to meet hygienic expectations of the public.

10.
Proc Natl Acad Sci U S A ; 114(40): 10737-10742, 2017 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-28923916

RESUMO

Ocular neovascularization is a devastating pathology of numerous ocular diseases and is a major cause of blindness. Caveolin-1 (Cav-1) plays important roles in the vascular system. However, little is known regarding its function and mechanisms in ocular neovascularization. Here, using comprehensive model systems and a cell permeable peptide of Cav-1, cavtratin, we show that Cav-1 is a critical player in ocular neovascularization. The genetic deletion of Cav-1 exacerbated and cavtratin administration inhibited choroidal and retinal neovascularization. Importantly, combined administration of cavtratin and anti-VEGF-A inhibited neovascularization more effectively than monotherapy, suggesting the existence of other pathways inhibited by cavtratin in addition to VEGF-A. Indeed, we found that cavtratin suppressed multiple critical components of pathological angiogenesis, including inflammation, permeability, PDGF-B and endothelial nitric oxide synthase expression (eNOS). Mechanistically, we show that cavtratin inhibits CNV and the survival and migration of microglia and macrophages via JNK. Together, our data demonstrate the unique advantages of cavtratin in antiangiogenic therapy to treat neovascular diseases.


Assuntos
Inibidores da Angiogênese/farmacologia , Anticorpos Monoclonais/farmacologia , Caveolina 1/fisiologia , Neovascularização de Coroide/prevenção & controle , MAP Quinase Quinase 4/metabolismo , Fragmentos de Peptídeos/farmacologia , Neovascularização Retiniana/prevenção & controle , Animais , Caveolina 1/farmacologia , Neovascularização de Coroide/metabolismo , Neovascularização de Coroide/patologia , Quimioterapia Combinada , Humanos , Camundongos Knockout , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
11.
Angew Chem Int Ed Engl ; 59(29): 11814-11818, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32270893

RESUMO

A universal approach is demonstrated for realizing dual-wavelength lasing in organic core-shell structured microlaser arrays, which show great promise in serving as all-color laser display panels. By alternately printing hydrophilic and hydrophobic laser dye solutions on preprocessed substrates, precisely patterned core-shell heterostructure arrays were obtained. The spatially separated core and shell independently function as optical resonators to support dual-wavelength tunable lasing in each heterostructure. Such a general method enables to flexibly control the lasing wavelength of the core-shell microlasers across a wide spectral range by systematically designing the gain media. Using as-prepared microlaser arrays as display panels, full-color laser displays were achieved with a color gamut much larger than that of standard RGB space. These results provide insights for design concepts and device construction for novel optoelectronic applications.

12.
Angew Chem Int Ed Engl ; 59(37): 15992-15996, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32519468

RESUMO

Miniaturized lasers with high spectral purity and wide wavelength tunability are crucial for various photonic applications. Here we propose a strategy to realize broadband-tunable single-mode lasing based on a photoisomerization-activated intramolecular charge-transfer (ICT) process in coupled polymer microdisk cavities. The photoisomerizable molecules doped in the polymer microdisks can be quantitatively transformed into a kind of laser dye with strong ICT character by photoexcitation. The gain region was tailored over a wide range through the self-modulation of the optically activated ICT isomers. Meanwhile, the resonant modes shifted with the photoisomerization because of a change in the effective refractive index of the polymer microdisk cavity. Based on the synergetic modulation of the optical gain and microcavity, we realized the broadband tuning of the single-mode laser. These results offer a promising route to fabricate broadband-tunable microlasers towards practical photonic integrations.

13.
J Am Chem Soc ; 141(13): 5116-5120, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30892879

RESUMO

We propose a general approach for obtaining dual-wavelength organic microlasers in amphiphilic Janus resonators, where hydrophilic and hydrophobic dyes can be spatially separated via polarity-driven encapsulation. Low-threshold dual-wavelength lasing was achieved in a single Janus particle with well-modulated output. This universal approach enables flexibly designing the lasing wavelength of the Janus microlasers in the full visible spectrum by systematically altering the encapsulated laser dyes. Our findings demonstrate a promising route to the photonic integration at the micro-/nanoscale that may lead to the innovation of concepts and device architectures for multifunctional optoelectronic applications.

14.
Angew Chem Int Ed Engl ; 58(39): 13803-13807, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31343800

RESUMO

Micro/nanoscale multicolor barcodes with unique identifiability and a small footprint play significant roles in applications such as multiplexed labeling and tracking systems. Now, a strategy is reported to design multicolor photonic barcodes based on 1D Ln-MOF multiblock heterostructures, where the domain-controlled emissive colors and different block lengths constitute the fingerprint of a corresponding heterostructure. The excellent heteroepitaxial growth characteristics of MOFs enable the effective modulation of the coding structures, thereby remarkably increasing the encoding capacity. The as-prepared multicolor barcodes enable an efficient authentication and exhibit great potential in fulfilling the functions of anti-counterfeiting, information security, and so on. The results will pave an avenue to novel hybrid MOFs for optical data recording and security labels.

15.
J Biol Inorg Chem ; 21(2): 213-26, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26714696

RESUMO

As one of the crucial factors of cataract formation, ultraviolet B (UVB) can lead to apoptosis of human lens epithelial cells. Zinc, a cell-protective metal against various toxic compounds, plays an important role in protecting target cells from damage. Nevertheless, it is still unclear whether zinc exhibits protective effect on human lens epithelial cells (HLE B-3) against UVB-induced damage. In this study, we investigated the protective effect of zinc chloride (ZnCl2) on UVB-induced HLE B-3 cell damage, explored the molecular mechanisms using real-time cell electronic sensing system, flow cytometry, real-time quantitative PCR and enzyme-linked immunosorbent assay techniques. The results show that ZnCl2 is a potential inhibitor of UVB-induced HLE B-3 cell damage, and the underlying mechanisms are involved in decreasing the overproduction of reactive oxygen species and mitochondrial dysfunction, promoting intracellular calcium homeostasis recovery, and thus maintaining cell normal physiological functions. Taken together, our findings suggest that appropriate zinc levels have potential for protecting HLE B-3 cells against UVB-induced damage, and this finding may be clinically useful.


Assuntos
Cristalino/efeitos dos fármacos , Cristalino/efeitos da radiação , Raios Ultravioleta , Zinco/farmacologia , Cálcio/metabolismo , Linhagem Celular , Cloretos/administração & dosagem , Homeostase , Humanos , Técnicas In Vitro , Cristalino/citologia , Espécies Reativas de Oxigênio/metabolismo , Compostos de Zinco/administração & dosagem
16.
Arch Biochem Biophys ; 560: 44-51, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25051343

RESUMO

Zinc (Zn), the second abundant trace element in living organisms, plays an important role in regulating cell metabolism, signaling, proliferation, gene expression and apoptosis. Meanwhile, the overload of Zn will disrupt the intracellular calcium homeostasis via impairing mitochondrial function. However, the specific molecular mechanism underlying zinc-induced calcium regulation remains poorly understood. In the present study, using zinc chloride (ZnCl2) as a stressor, we investigated the effect of exogenous Zn(2+) in regulating murine photoreceptor cell viability, reactive oxygen species (ROS), cell cycle distribution and calcium homeostasis as well as plasma membrane calcium ATPase (PMCA) isoforms (PMCA1 and PMCA2, i.e., ATP2B1, ATP2B2) expression. We found that the exogenous Zn(2+) in the exposure range (31.25-125.0 µmol/L) results in the overgeneration of ROS, cell cycle arrest at G2/M phases, elevation of cytosolic [Ca(2+)], inactivation of Ca(2+)-ATPase and reduction of both PMCA1 and PMCA2 in 661 W cells, and thus induces cell death. In conclusion, ZnCl2 exposure can elevate the cytosolic [Ca(2+)], disrupt the intracellular calcium homeostasis, further initiate Ca(2+)-dependent signaling pathway in 661 W cells, and finally cause cell death. Our results will facilitate the understanding of cell death induced by the zinc ion-mediated calcium homeostasis disruption.


Assuntos
Cálcio/metabolismo , Cloretos/farmacologia , Homeostase/efeitos dos fármacos , Células Fotorreceptoras/citologia , Células Fotorreceptoras/efeitos dos fármacos , Compostos de Zinco/farmacologia , Animais , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Camundongos , Células Fotorreceptoras/metabolismo , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo
17.
Angew Chem Int Ed Engl ; 53(18): 4561-6, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24683064

RESUMO

As macroscopic three dimensional (3D) architectures show increasing significance, much effort has been devoted to the hierarchical organization of 1D nanomaterials into serviceable macroscopic 3D assemblies. How to assemble 1D nanoscale building blocks into 3D hierarchical architectures is still a challenge. Herein we report a general strategy based on the use of ice as a template for assembling 1D nanostructures with high efficiency and good controllability. Free-standing macroscopic 3D Ag nanowire (AgNW) assemblies with hierarchical binary-network architectures are then fabricated from a 1D AgNW suspension for the first time. The microstructure of this 3D AgNW network endows it with electrical conductivity and allows it to be made into stretchable and foldable conductors with high electromechanical stability. These properties should make this kind of macroscopic 3D AgNW architecture and it composites suitable for electronic applications.


Assuntos
Condutividade Elétrica , Gelo , Fenômenos Mecânicos , Nanoestruturas/química , Nanofios/química , Prata/química
18.
Gels ; 10(4)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38667686

RESUMO

Aerogel fibers, characterized by their ultra-low density and ultra-low thermal conductivity, are an ideal candidate for personal thermal management as they hold the potential to effectively reduce the energy consumption of room heating and significantly contribute to energy conservation. However, most aerogel fibers have weak mechanical properties or require complex manufacturing processes. In this study, simple continuous silk fibroin-agarose composite aerogel fibers (SCAFs) were prepared by mixing agarose with silk fibroin through wet spinning and rapid gelation, followed by solvent replacement and supercritical carbon dioxide treatment. Among them, the rapid gelation of the SCAFs was achieved using agarose physical methods with heat-reversible gel properties, simplifying the preparation process. Hydrophobic silk fibroin-agarose composite aerogel fibers (HSCAFs) were prepared using a simple chemical vapor deposition (CVD) method. After CVD, the HSCAFs' gel skeletons were uniformly coated with a silica layer containing methyl groups, endowing them with outstanding radial elasticity. Moreover, the HSCAFs exhibited low density (≤0.153 g/cm3), a large specific surface area (≥254.0 m2/g), high porosity (91.1-94.7%), and excellent hydrophobicity (a water contact angle of 136.8°). More importantly, they showed excellent thermal insulation performance in low-temperature (-60 °C) or high-temperature (140 °C) environments. The designed HSCAFs may provide a new approach for the preparation of high-performance aerogel fibers for personal thermal management.

19.
ACS Appl Mater Interfaces ; 16(20): 26757-26767, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38722961

RESUMO

Aerogel fibers are good thermal insulators, suitable for weaving, and show potential as the next generation of intelligent textiles that can effectively reduce heat consumption for personal thermal management. However, the production of continuous aerogel fibers from biomass with sufficient strength and radial elasticity remains a significant challenge. Herein, continuous gel fibers were produced via wet spinning using agarose (AG) as the matrix, 2,2,2,6,6-tetramethylpiperidine-1-oxyl radical-oxidized cellulose nanofibers (TOCNs) as the reinforcing agent, and no other chemical additives by utilizing the gelling properties of AG. Supercritical drying and chemical vapor deposition (CVD) were then used to produce hydrophobic AG-TOCN aerogel fibers (HATAFs). During CVD, the HATAF gel skeleton was covered with an isostructural silica coating. Consequently, the HATAFs can recover from radial compression under 60% strain. Moreover, the HATAFs have low densities (≤0.14 g cm-3), high porosities (≥91.8%), high specific surface areas (≥188 m2 g-1), moderate tensile strengths (≤1.75 MPa), excellent hydrophobicity (water contact angles of >130°), and good thermal insulating properties at different temperatures. Thus, HATAFs are expected to become a new generation of materials for efficient personal thermal management.

20.
Mol Cell Biochem ; 382(1-2): 263-72, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23817774

RESUMO

Ultraviolet B (UVB) could lead to the apoptosis of human lens epithelial cell and be hypothesized to be one of the important factors of cataractogenesis. In the human lens, Ca(2+)-ATPase is a major determinant of calcium homeostasis. Plasma membrane calcium ATPase1 (PMCA1) is a putative "housekeeping" isoform and is widely expressed in all tissues and cells, which plays an important role in calcium homeostasis. However, the effects of UVB-irradiation on the expression of PMCA1 and the cellular calcium homeostasis are still unclear. In the present study, we cultured human lens epithelial cells (HLE B-3) in vitro and investigated the effects of UVB irradiation on the expression of PMCA1 and the intracellular calcium homeostasis using real-time cell electronic sensing system, flow cytometry, fluo-3/AM probes, real-time quantitative PCR, and enzyme-linked immunosorbent assay techniques. We found that UVB irradiation could induce human lens epithelial cell death, cause intracellular calcium ion (Ca(2+)) elevation, inhibit Ca(2+)-ATPase activity and decrease the expression of PMCA1 at gene and protein levels, suggesting that the downregulation of PMCA1 and the disruption of calcium homeostasis may play important roles in UVB-induced HLE B-3 cell apoptosis.


Assuntos
Cálcio/metabolismo , Células Epiteliais/enzimologia , Células Epiteliais/efeitos da radiação , Homeostase/efeitos da radiação , Cristalino/citologia , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Raios Ultravioleta , Anexina A5/metabolismo , Linhagem Celular , Ensaio de Imunoadsorção Enzimática , Fluorescência , Humanos , Peróxido de Hidrogênio/metabolismo , Radical Hidroxila/metabolismo , Espaço Intracelular/metabolismo , Espaço Intracelular/efeitos da radiação , Potencial da Membrana Mitocondrial/efeitos da radiação , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Propídio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
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