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1.
ACS Appl Mater Interfaces ; 13(46): 55756-55765, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34780161

RESUMO

Robotic hands with tactile perception can perform more advanced and safer operations, such as material recognition. Nanowires with high sensitivity, fast response, and low power consumption are suitable for multifunctional flexible tactile sensors to provide the tactile perception of robotic hands. In this work, we designed a multifunctional soft robotic finger with a built-in nanoscale temperature-pressure tactile sensor for material recognition. The flexible multifunctional tactile sensor integrates a nanowire-based temperature sensor and a conductive sponge pressure sensor to measure the temperature change rate and contact pressure simultaneously. The developed nanoscale temperature and conductive sponge pressure sensor can reach a high sensitivity of 1.196%/°C and 13.29%/kPa, respectively. With this multifunctional tactile sensor, the soft finger can quickly recognize four metals within three contact pressure ranges and 13 materials within a high contact pressure range. By combining tactile information and artificial neural networks, the soft finger can recognize the materials precisely with a high recognition accuracy of 92.7 and 95.9%, respectively. This work proves the application potential of the multifunctional soft robot finger in material recognition.

2.
Psych J ; 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34794208

RESUMO

Previous studies have consistently confirmed the positive relationship between work meaningfulness and one's persistent behavior in the workplace. However, most existing studies have focused on examining the direct effect of work meaningfulness, paid less attention to the condition under which it works well. In this study, we adopted a 2 (work meaningfulness: disclosure vs. non-disclosure) × 2 (level of action identification: high vs. low) between-subject experimental design and investigated the moderating role of action identification level in the relationship between work meaningfulness disclosure and one's persistent behavior. The result indicated that both work characteristics (i.e., work meaningfulness) and personal factors influence work behaviors, since participants who identified their work behaviors at a lower/concrete level benefited more from work meaningfulness disclosure. Given that personal factors have long been neglected in previous work meaningfulness literature, our findings could help advance existing research on work meaningfulness.

3.
Cytotherapy ; 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34598900

RESUMO

BACKGROUND AIMS: Stem cell therapy is a novel therapy being explored for AD. The molecular mechanism of its effect is still unclear. The authors investigated the effects and mechanism by injection of SHEDs into an AD mouse model. METHODS: SHEDs were cultured in vitro and injected into AD SAMP8 mice by caudal vein, and SHEDs labeled via synthetic dye showed in vivo migration to the head. The cognitive ability of SAMP8 mice was evaluated via Barnes maze and new object recognition. The pathological indicators of AD, including Tau, amyloid plaques and inflammatory factors, were examined at the protein or RNA level. Next, macro-proteomics analysis and weighted gene co-expression network analysis (WGCNA) based on protein groups and behavioral data were applied to discover the important gene cluster involved in the improvement of AD by SHEDs, which was further confirmed in an AD model in both mouse and cell lines. RESULTS: SHED treatment improved the cognitive ability and pathological symptoms of SAMP8 mice. Proteomics analysis indicated that these improvements were tightly related to the mitochondria, which was proved through examination of the shape and function of mitochondria both in vivo (SAMP8 brain) and in vitro (SH-SY5Y cells). Finally, the core targets of SHEDs in the mitochondrial pathway, Hook3, Mic13 and MIF, were screened out and confirmed in vivo. CONCLUSIONS: SHED treatment significantly relieved AD symptoms, improved cognitive ability and reversed memory loss in an AD mouse model, possibly through the recovery of dysfunctional mitochondria. These results raise the possibility that SHED may ease the symptoms of AD by targeting the mitochondria.

4.
Cell Transplant ; 30: 9636897211042927, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34633878

RESUMO

Stem cells in different types may interact with each other to maintain homeostasis or growth and the interactions are complicated and extensive. There is increasing evidence that mesenchymal-epithelial interactions in early morphogenesis stages of both tooth and hair follicles show many similarities. In order to explore whether stem cells from one tissue could interact with cells from another tissue, a series of experiments were carried out. Here we successfully extracted and identified stem cells from human exfoliated deciduous teeth (SHED) of 8-12 years old kids, and then found that SHED could promote hair regeneration in a mouse model. In vitro, SHED shortened the hair regeneration cycle and promoted the proliferation and aggregation of dermal cells. In vivo, when SHED and skin cells of C57 mice were subcutaneously co-transplanted to nude mice, more hair was formed than skin cells without SHED. To further explore the molecular mechanism, epidermal and dermal cells were freshly extracted and co-cultured with SHED. Then several signaling molecules in hair follicle regeneration were detected and we found that the expression of Sonic Hedgehog (Shh) and Glioma-associated oncogene 1 (Gli1) was up-regulated. It seems that SHED may boost the prosperity of hairs by increase Shh/Gli1 pathway, which brings new perspectives in tissue engineering and damaged tissue repairing.

5.
Dalton Trans ; 50(35): 12301-12307, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34519756

RESUMO

Spinel ferrites are considered practical and promising oxygen evolution reaction (OER) and urea oxidation reaction (UOR) electrocatalysts because of their advantages in the adsorption and activation of electrocatalytic substances. A CeO2 functional metal oxide was used to modify a spinel oxide in order to further improve the electrocatalytic performance of the spinel oxide. In this work, a CeO2@CoFe2O4/NF hybrid nanostructure was synthesized for the first time by typical hydrothermal and calcination methods. In an alkaline medium, CeO2@CoFe2O4/NF displays superior OER activity and needs an overpotential of 213 mV to deliver a current density of 100 mA cm-2, which makes it one of the most active catalysts reported so far. In addition, the as-prepared CeO2@CoFe2O4/NF material needs a potential of 1.40 V at the same current density in 1.0 M KOH with 0.5 M urea, which displays superior UOR activity. The CeO2@CoFe2O4/NF catalyst also displays good durability and the performance of the electrode is negligibly attenuated at a large current intensity of 125 mA cm-2. Experimental results demonstrate that the activity of the CeO2@CoFe2O4/NF catalyst is ascribed to the exposure of more active centers and a faster electron transfer rate. This work develops a novel method for exploiting Earth-abundant, robust and environmentally friendly OER and UOR electrocatalysts.

6.
Dalton Trans ; 50(39): 14001-14008, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34546267

RESUMO

The design and synthesis of hybrid core-shell catalysts is of great significance for obtaining an excellent performance of hydrogen evolution reaction (HER). However, it remains a challenge to explore the exact active sites and research the catalytic mechanism for HER. Here, a series of Ni3S2@MOOH/NF (M = Fe, Ni, Cu, Mn and Co) hybrid structures is firstly in-site grown on Ni foam by the typical hydrothermal and electrodeposition methods. The Ni3S2@NiOOH/NF catalyst with a core-shell structure exhibits a relatively low overpotential of 79 mV for HER at a current density of 10 mA cm-2, which is one of the best catalytic activities reported so far. Moreover, it also shows good stability in the long-term durability test. Various spectral analysis and density functional theory calculations demonstrate that NiOOH is favorable for the adsorption of water molecules, and the S atom at the interface between Ni3S2 and NiOOH is favorable for the adsorption of H intermediates, which strongly accelerates the HER process in alkaline solution. This work provides a general strategy for the synthesis of electrocatalytic materials, which can be used for efficient electrocatalytic water splitting reactions.

7.
Aging (Albany NY) ; 13(18): 22390-22411, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34543233

RESUMO

Studies reveal a linkage of miR-29s in aging and Parkinson's disease (PD). Here we show that the serum levels of miR-29s in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mice exhibited dynamic changes. The role of miR-29b2/c in aging and PD was studied utilizing miR-29b2/c gene knockout mice (miR-29b2/c KO). miR-29b2/c KO mice were characterized by a markedly lighter weight, kyphosis, muscle weakness and abnormal gait, when compared with wild-type (WT) mice. The WT also developed apparent dermis thickening and adipose tissue reduction. However, deficiency of miR-29b2/c alleviated MPTP-induced damages of the dopaminergic system and glial activation in the nigrostriatal pathway and consequently improved the motor function of MPTP-treated KO mice. Knockout of miR-29b2/c inhibited the expression of inflammatory factors in 1-methyl-4-phenylpyridinium (MPP+)-treated primary cultures of mixed glia, primary astrocytes, or LPS-treated primary microglia. Moreover, miR-29b2/c deficiency enhanced the activity of AMPK but repressed the NF-κB p65 signaling in glial cells. Our results show that miR-29b2/c KO mice display the progeria-like phenotype. Less activated glial cells and repressed neuroinflammation might bring forth dopaminergic neuroprotection in miR-29b2/c KO mice. Conclusively, miR-29b2/c is involved in the regulation of aging and plays a detrimental role in Parkinson's disease.

8.
Int J Biochem Cell Biol ; 141: 106086, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34551339

RESUMO

Human umbilical cord mesenchymal stem cells (hUC-MSCs) are a potential clinical material in regenerative medicine applications. Metformin has shown safety and effectiveness as a clinical drug. However, the effect of metformin as a treatment on hUC-MSCs is unclear. Our research aimed to explore the effects of metformin on the osteogenesis, adipogenesis and angiogenesis of hUC-MSCs, and attempted to explain the molecular fluctuations of metformin through the mapping of protein profiles. Proliferation assay, osteogenic and adipogenic differentiation induction, cell cycle, flow cytometry, quantitative proteomics techniques and bioinformatics analysis were used to detect the influences of metformin treatment on hUC-MSCs. Our results demonstrated that low concentrations of metformin promoted the proliferation of hUC-MSCs, but high concentrations of metformin inhibited it. Metformin exhibited promotion of osteogenesis but inhibition of adipogenesis. Metformin treated hUC-MSCs up-regulated the expression of osteogenic marker ALP, OCN and RUNX2, but down-regulated the expression of adipogenic markers PPARγ and LPL. Proteomics analysis found that up-regulation of differentially expressed proteins in metformin treatment group involved the biological process of cell migration in Gene Ontology analysis. Metformin enhanced cell migration of HUVEC in a co-culture system, and hUC-MSCs treated with metformin exhibited stronger angiogenesis in vitro and in vivo compared to the hUC-MSCs group. The results of RT-qPCR revealed that the SCF and VEGFR2 were raised in metformin treatment. This study can promote the application of hUC-MSCs treated with metformin to tissue engineering for vascular reconstruction and angiogenesis.

9.
Stem Cell Res Ther ; 12(1): 457, 2021 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-34391472

RESUMO

Stem cell therapy has shown great efficacy in many diseases. However, the treatment mechanism is still unclear, which is a big obstacle for promoting clinical research. Therefore, it is particularly important to track transplanted stem cells in vivo, find out the distribution and condition of the stem cells, and furthermore reveal the treatment mechanism. Many tracking methods have been developed, including magnetic resonance imaging (MRI), fluorescence imaging, and ultrasound imaging (UI). Among them, MRI and UI techniques have been used in clinical. In stem cell tracking, a major drawback of these technologies is that the imaging signal is not strong enough, mainly due to the low cell penetration efficiency of imaging particles. Cell penetrating peptides (CPPs) have been widely used for cargo delivery due to its high efficacy, good safety properties, and wide delivery of various cargoes. However, there are few reports on the application of CPPs in current stem cell tracking methods. In this review, we systematically introduced the mechanism of CPPs into cell membranes and their advantages in stem cell tracking, discussed the clinical applications and limitations of CPPs, and finally we summarized several commonly used CPPs and their specific applications in stem cell tracking. Although it is not an innovation of tracer materials, CPPs as a powerful tool have broad prospects in stem cell tracking.


Assuntos
Peptídeos Penetradores de Células , Membrana Celular , Rastreamento de Células , Sistemas de Liberação de Medicamentos , Células-Tronco
10.
Cell Prolif ; 54(8): e13094, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34312932

RESUMO

OBJECTIVES: Parkinson's disease (PD) is a common neurodegenerative disorder characterized by the progressive and selective degeneration of dopaminergic neurons. Microglial activation and neuroinflammation are associated with the pathogenesis of PD. However, the relationship between microglial activation and PD pathology remains to be explored. MATERIALS AND METHODS: An acute regimen of MPTP was administered to adult C57BL/6J mice with normal, much reduced or repopulated microglial population. Damages of the dopaminergic system were comprehensively assessed. Inflammation-related factors were assessed by quantitative PCR and Multiplex immunoassay. Behavioural tests were carried out to evaluate the motor deficits in MPTP-challenged mice. RESULTS: The receptor for colony-stimulating factor 1 inhibitor PLX3397 could effectively deplete microglia in the nigrostriatal pathway of mice via feeding a PLX3397-formulated diet for 21 days. Microglial depletion downregulated both pro-inflammatory and anti-inflammatory molecule expression at baseline and after MPTP administration. At 1d post-MPTP injection, dopaminergic neurons showed a significant reduction in PLX3397-fed mice, but not in control diet (CD)-fed mice. However, partial microglial depletion in mice exerted little effect on MPTP-induced dopaminergic injuries compared with CD mice at later time points. Interestingly, microglial repopulation brought about apparent resistance to MPTP intoxication. CONCLUSIONS: Microglia can inhibit PD development at a very early stage; partial microglial depletion has little effect in terms of the whole process of the disease; and microglial replenishment elicits neuroprotection in PD mice.


Assuntos
Intoxicação por MPTP/patologia , Microglia/metabolismo , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/administração & dosagem , Aminopiridinas/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Mediadores da Inflamação/metabolismo , Intoxicação por MPTP/metabolismo , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Pirróis/farmacologia , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo
11.
Dalton Trans ; 50(31): 10880-10887, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34302157

RESUMO

The design and development of robust and environmentally friendly electrocatalytic materials are of great significance to the hydrogen production industry for the electrolysis of water. A series of P-Co3O4@NiCo-LDH/NF materials was firstly successfully synthesized by a hydrothermal method, high temperature calcination and an electrochemical deposition approach when sodium hypophosphite was used as the source of P and Ni(NO3)2·6H2O as the source of nickel and introduced cobalt at the same time. The structure, composition, morphology and electrochemical performance of the P-Co3O4@NiCo-LDH/NF electrocatalytic material were determined by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy and electrochemical performance testing. It is worth noting that the P-Co3O4@NiCo-LDH-2/NF material presents excellent hydrogen evolution reaction performance in 1 M KOH alkaline solution. It only needs an overpotential of 181 mV to drive a current density of 100 mA cm-2, which is one of the best catalytic activities reported so far. The experimental results and theoretical calculations demonstrate that the electrocatalytic activity of the P-Co3O4@NiCo-LDH-2/NF material is attributed to the faster electron transfer rate, exposure of more active sites, optimal water adsorption energy and better electrical conductivity.

12.
Stem Cells Int ; 2021: 8886854, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34194509

RESUMO

Since mesenchymal stem cells derived from human teeth are characterized as having the properties of excellent proliferation, multilineage differentiation, and immune regulation. Dental stem cells exhibit fibroblast-like microscopic appearance and express mesenchymal markers, embryonic markers, and vascular markers but do not express hematopoietic markers. Dental stem cells are a mixed population with different sensitive markers, characteristics, and therapeutic effects. Single or combined surface markers are not only helpful for understanding the subpopulation of mixed stem cell populations according to cell function but also for improving the stable treatment effect of dental stem cells. Focusing on the discovery and characterization of stem cells isolated from human teeth over the past 20 years, this review outlines the effect of marker sorting on cell proliferation and differentiation ability and the assessment of the clinical application potential. Classified dental stem cells from markers and functional molecules can solve the problem of heterogeneity and ensure the efficacy of cell therapy strategies including dentistry, neurologic diseases, bone repair, and tissue engineering.

13.
J Proteomics ; 245: 104280, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34089896

RESUMO

Background The study of molecular profiling of dental pulp stem cells (DPSCs) and periodontal ligament stem cells (PDLSCs) contributes to understanding the high proliferation ability and multi-lineage differentiation potential. Objectives The aim of the study was to compare the protein abundance and specific markers of DPSCs and PDLSCs by protein profiles. Material and methods The DPSCs and PDLSCs extracted from the same tooth were lysed with 3 biological replicates and the protein was collected. Two-dimensional electrophoresis technology and TMT proteomics were used to separate and identify proteins. The data are available via ProteomeXchange with identifier PXD021997. The RT-qPCR detection of mRNA expression revealed a special marker for distinguishing two kinds of dental stem cells. Results Compared with PDLSCs, 962 differential proteins (DAPs) were up-regulated, and 127 were down-regulated in DPSCs. In the up-regulated DAPs, two high-scoring sub-networks were detected for neural-related molecules, which encode cell vesicle transport and mitochondrial energy transfer to regulate cell proliferation and secretion factors. A large number of cell adhesion molecules were distinguished among the highly expressed molecules of PDLSCs, supporting that stem cells provide cell attachment functions. It was interpreted ENPL, HS90A and HS90B were highly expressed in DPSCs, while CKB was highly abundant in PDLSCs. Another cell group confirmed that these molecules can be used as special biomarkers to identify and distinguish between DPSCs and PDLSCs. Conclusions This study can promote the basic research and clinical application of dental stem cells. Significance The high-throughput protein profiles were tested by combining two-dimensional gel proteomics and TMT-based proteomics. The proteomics of DPSCs and PDLSCs without individual difference demonstrated an accurate and comprehensive molecular expression profiles and interpretation of neural application potential, this study promotes the basic research of dental stem cells and clinical application.


Assuntos
Células-Tronco Mesenquimais , Ligamento Periodontal , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Polpa Dentária , Humanos , Proteômica , Células-Tronco
14.
Dalton Trans ; 50(25): 8955-8962, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34109953

RESUMO

The development of high-performance and cost-effective bifunctional water splitting catalysts has enormous significance in the hydrogen production industry from water electrolysis. Herein, an in situ Co and N co-doping method was developed to improve the electrocatalytic performance of Ni3S2 catalysts. The Co-N-Ni3S2/NF is successfully synthesized for the first time by a one-step hydrothermal method, wherein nickel foam, thioacetamide and Co(NO3)2·6H2O are used as the nickel source, sulfur source, nitrogen source and cobalt source. Co-N-Ni3S2/NF exhibits excellent oxygen evolution reaction activity (an overpotential of 285 mV@50 mA cm-2) and hydrogen evolution reaction activity (an overpotential of 215 mV@10 mA cm-2) in 1 M KOH solution. The electrolytic cell displayed a low cell voltage of 1.50 V when the Co-N-Ni3S2/NF material was used as the bifunctional water splitting electrocatalyst, which is one of the best catalysts reported so far. Density functional theory calculations show that Co-N-Ni3S2/NF exhibits stronger water adsorption energy than those of N-Ni3S2/NF, Co-Ni3S2/NF and Ni3S2/NF. It is proved that the doping of Co and N can effectively regulate the electron cloud density of Ni, thus enhancing the electrochemical activity of Co-N-Ni3S2/NF.

15.
PLoS One ; 16(6): e0253981, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34185800

RESUMO

Dynamic compaction is a cost-effective foundation treatment technology, that is widely used in various types and conditions of foundations. However, due to the limitation of natural conditions (water content between 3% and 8%) in north-western China, it is difficult to meet the requirements of the optimal water content during dynamic compaction. To better treat a foundation with a low water content, a series of model tests were carried out by using homemade test equipment to study the influence of the ramming energy and η value on the efficiency of dynamic compaction under a low water content. The results showed that the improvement of the energy level could compensate for the poor effect of dynamic compaction caused by a low water content in arid regions. Compared with that at the optimal water content, the efficiency of dynamic compaction was 58.1% to 66.2% at a low water content and excited the optimal energy level. Increasing the η value was also beneficial to improving the effect of dynamic compaction. Hence, the optimal energy level combined with the appropriate η value is of great merit in treating the foundation of arid regions by using the dynamic compaction method, which provides new parameter suggestions and engineering guidance for dynamic compaction construction in arid areas.


Assuntos
Conservação dos Recursos Hídricos , Solo/química , Recursos Hídricos , Água/química , China , Humanos
16.
Dalton Trans ; 50(19): 6650-6658, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-33908546

RESUMO

Exploiting environmentally friendly and robust electrocatalysts for overall water splitting is of utmost importance in order to alleviate the excessive global energy consumption and climate change. Herein, a simple phosphoselenization method was used to prepare Co2P and CoSe2 coupled nanosheet and nanoneedle composite materials on nickel foam (Co2P/CoSe2/NF). Density functional theory calculations showed that Co2P had a higher water adsorption energy compared with CoSe2, indicating that H2O molecules are strongly adsorbed on the active sites of Co2P, which speeds up the kinetic process of water splitting. The Co2P/CoSe2-300 material displayed superior electrocatalytic activity for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in an alkaline medium. It's worth noting that the Co2P/CoSe2-300 composite material nanoarrays merely needed an ultralow overpotential of 280 mV to drive a current intensity of 100 mA cm-2 for OER. In addition, when a two-electrode system was constructed for overall water splitting, the current intensity of 20 mA cm-2 could be reached while requiring an ultrasmall cell voltage of 1.52 V, which is one of the best catalytic activities reported up to now. Experimental and density functional theory calculations showed that the superior electrocatalytic performance of Co2P/CoSe2-300 could be attributed to its higher electron-transfer rate, higher water adsorption energy, and the synergistic effect of Co2P and CoSe2. Our work provides a novel approach for the one-step construction of composite materials as environmentally friendly and inexpensive water splitting catalysts.

17.
Int J Biol Macromol ; 178: 229-239, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33647340

RESUMO

The construction of protein abundance profiles helps to interpret the clinical applications of stem cells. Dental pulp stem cells (DPSCs) and gingival mesenchymal stem cells (GMSCs) can be isolated from teeth and used as a highly convenient clinical potential material. Here, we aimed to explore commonalities and differences of DPSCs and GMSCs at the protein level. TMT-based quantitative proteomics and two-dimensional gel electrophoresis technology were used in combination to describe the protein profile of DPSCs and GMSCs extracted from the same donor. A total of 2821 proteins were identified by LC-MS/MS, of which 248 differentially abundant proteins (DAPs) were highly expressed in GMSCs while 782 proteins were highly expressed in DPSCs. The biological functions and molecular pathways of DAPs were annotated with GO enrichment and KEGG analysis. The relationship between molecular abundance and cell characteristics including source, proliferation, angiogenesis and inflammation were connected by WGCNA. Special markers, including Calreticulin (CALR), Annexin A5 (ANXA5) and Rho GDP dissociation inhibitor alpha (GDIR1), were proposed to distinguish DPSCs from GMSCs. Our results provide a molecular basis for in-depth understanding of the protein composition and special functions of dental stem cells, and promote the potential clinical application.


Assuntos
Calreticulina/metabolismo , Polpa Dentária , Gengiva , Células-Tronco Mesenquimais , Biomarcadores , Células Cultivadas , Polpa Dentária/citologia , Polpa Dentária/metabolismo , Gengiva/citologia , Gengiva/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo
18.
BMC Vet Res ; 17(1): 112, 2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33676490

RESUMO

BACKGROUND: Dogs are domesticated wolves. Change of living environment, such as diet and veterinary care may affect the gut bacterial flora of dogs. The aim of this study was to assess the gut bacterial diversity and function in dogs compared with captive wolves. We surveyed the gut bacterial diversity of 27 domestic dogs, which were fed commercial dog food, and 31 wolves, which were fed uncooked meat, by 16S rRNA sequencing. In addition, we collected fecal samples from 5 dogs and 5 wolves for shotgun metagenomic sequencing to explore changes in the functions of their gut microbiome. RESULTS: Differences in the abundance of core bacterial genera were observed between dogs and wolves. Together with shotgun metagenomics, the gut microbiome of dogs was found to be enriched in bacteria resistant to clinical drugs (P < 0.001), while wolves were enriched in bacteria resistant to antibiotics used in livestock (P < 0.001). In addition, a higher abundance of putative α-amylase genes (P < 0.05; P < 0.01) was observed in the dog samples. CONCLUSIONS: Living environment of dogs and domestic wolves has led to increased numbers of bacteria with antibiotic resistance genes, with exposure to antibiotics through direct and indirect methods. In addition, the living environment of dogs has allowed the adaptation of their microbiota to a starch-rich diet. These observations align with a domestic lifestyle for domestic dogs and captive wolves, which might have consequences for public health.


Assuntos
Bactérias/classificação , Cães/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Lobos/microbiologia , Amilases/genética , Animais , Antibacterianos , Bactérias/efeitos dos fármacos , China , Dieta/veterinária , Farmacorresistência Bacteriana/genética , RNA Ribossômico 16S/genética , Amido
19.
Chem Asian J ; 16(8): 959-965, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33660405

RESUMO

The development of highly efficient, inexpensive, abundant and non-precious metal electrocatalysts is the lifeblood of the hydrogen production industry, especially the hydrogen production industry by electrolysis of water. A Fe-Co-S/NF bifunctional electrocatalyst with nanoflower-like structure was synthesized on three-dimensional porous nickel foam through one-step hydrothermal and one-step high-temperature sulfuration operations, and the material displays high-efficiency electrocatalytic performance. As a catalyst for the hydrogen evolution reaction, Fe-Co-S/NF can drive a current density of 10 mA/cm2 at an overpotential of 143 mV with a Tafel slope of 80.2 mV/dec. When it was used as an oxygen evolution reaction catalyst, it exhibits good OER reactivity with a low Tafel slope (82.6 mV/dec) and with requiring only 117 mV overpotential to drive current densities up to 50 mA/cm2 . In addition, the Fe-Co-S/NF//Fe-Co-S/NF electrolytic cell was assembled, an electrolysis voltage of 1.64 V is required to drive a current density of 50 mA/cm2 , which is one of the most active catalysts reported so far. This work indicates that the introduction of S, P and Se treating processes could effectively improve electrical conductivity of the material and enhance the catalytic activity of the material. This work offers an effective and convenient method for improving the morphology of the catalyst, increasing the surface area of the catalyst and developing high-efficiency and low-cost catalysts.

20.
Dalton Trans ; 50(8): 2964-2972, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33564801

RESUMO

Electrochemical water splitting has become one of the state of the art approaches to generate hydrogen. It is important to exploit relatively low toxicity, low cost and environmentally friendly water splitting electrocatalysts. A series of Cu-Ni-M (M = S, P and Se) materials were firstly in situ grown on Ni foam and these materials showed excellent water splitting activity. The Cu-Ni-S material shows excellent oxygen evolution reaction performance (200 mV@20 mA cm-2) and the Cu-Ni-P sample shows an effective hydrogen evolution reaction performance (52 mV@10 mA cm-2). When the Cu-Ni-S and Cu-Ni-P materials were assembled into a two-electrode system, the Cu-Ni-S/NF//Cu-Ni-P/NF electrode pairs display superior water splitting activity (1.50 V@20 mA cm-2), which is one of the best electrocatalytic activities reported so far. The experimental analysis demonstrates that the excellent performance of the Cu-Ni-S/NF and Cu-Ni-P/NF materials is attributed to the rapid electron transfer rate, increased electrocatalytically active area, more exposure to active sites and the superior synergistic catalytic factor of Ni2+ and Cu2+. It was found that amorphous oxides were in situ generated on the outside surface of the catalyst through the analysis of the catalyst after the reaction, and they were the real electrocatalytically active centers. Density functional theory demonstrates that the in situ generated Cu-doped NiOOH shows the optimal water adsorption energy compared with NiOOH. This work offers novel views for the design of relatively low toxicity, stable and inexpensive water splitting electrocatalysts.

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