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1.
Artigo em Inglês | MEDLINE | ID: mdl-31597487

RESUMO

Introduction: Microwaves (MWs) quickly deliver relatively high temperatures into tumors and cover a large ablation zone. We present a research protocol for using water-cooled double-needle MW ablation arrays for tumor ablation here. Material and methods: Our research program includes computer modeling, tissue-mimicking phantom experiments, and in vitro swine liver experiments. The computer modeling is based on the finite element method (FEM) to evaluate ablation temperature distributions. In tissue-mimicking phantom and in vitro swine liver ablation experiments, the performances of the new device and the single-needle MW device currently used in clinical practice are compared. Results: FEM shows that the maximum transverse ablation diameter (MTAD) is 4.2 cm at 100 W output and 300 s (assessed at the 50 °C isotherm). In the tissue-mimicking phantom, the MTDA is 2.6 cm at 50 W and 300 s in single-needle MW ablation, and 4 cm in double needle MW ablation array. In in vitro swine liver experiments, the MTAD is 2.820 ± 0.127 cm at 100 W and 300 s in single-needle MW ablation, and 3.847 ± 0.103 cm in MW ablation array. Conclusion: A new type of water-cooled MW ablation array is designed and tested, and has potential advantages over currently used devices.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31596568

RESUMO

Regeneration of an injured meniscus continues to be a scientific challenge due to its poor self-healing potential. Tissue engineering provides an avenue for regenerating a severely damaged meniscus. In this study, we first investigated the superiority of five concentrations (0%, 0.5%, 1%, 2%, and 4%) of meniscus extracellular matrix (MECM)-based hydrogel in promoting cell proliferation and the matrix-forming phenotype of meniscal fibrochondrocytes (MFCs). We found that the 2% group strongly enhanced chondrogenic marker mRNA expression and cell proliferation compared to the other groups. Moreover, the 2% group showed the highest glycosaminoglycan (GAG) and collagen production by day 14. We then constructed a hybrid scaffold by 3D printing a wedge-shaped poly(ε-caprolactone) (PCL) scaffold as a backbone, followed by injection with the optimized MECM-based hydrogel (2%), which served as a cell delivery system. The hybrid scaffold (PCL-hydrogel) clearly yielded favorable biomechanical properties close to those of the native meniscus. Finally, PCL scaffold, PCL-hydrogel, and MFCs-loaded hybrid scaffold (PCL-hydrogel-MFCs) were implanted into the knee joints of New Zealand rabbits that underwent total medial meniscectomy. Six months postimplantation we found that the PCL-hydrogel-MFCs group exhibited markedly better gross appearance and cartilage protection than the PCL scaffold and PCL-hydrogel groups. Moreover, the regenerated menisci in the PCL-hydrogel-MFCs group had similar histological structures, biochemical contents, and biomechanical properties as the native menisci in the sham operation group. In conclusion, PCL-MECM-based hydrogel hybrid scaffold seeded with MFCs can successfully promote whole meniscus regeneration, and cell-loaded PCL-MECM-based hydrogel hybrid scaffold may be a promising strategy for meniscus regeneration in the future.

3.
Theranostics ; 9(17): 5105-5121, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31410204

RESUMO

Heterogeneity of mesenchymal stem cells (MSCs) influences the cell therapy outcome and the application in tissue engineering. Also, the application of subpopulations of MSCs in cartilage regeneration remains poorly characterized. CD146+ MSCs are identified as the natural ancestors of MSCs and the expression of CD146 are indicative of greater pluripotency and self-renewal potential. Here, we sorted a CD146+ subpopulation from adipose-derived mesenchymal stem cells (ADSCs) for cartilage regeneration. Methods: CD146+ ADSCs were sorted using magnetic activated cell sorting (MACS). Cell surface markers, viability, apoptosis and proliferation were evaluated in vitro. The molecular signatures were analyzed by mRNA and protein expression profiling. By intra-articular injections of cells in a rat osteochondral defect model, we assessed the role of the specific subpopulation in cartilage microenvironment. Finally, CD146+ ADSCs were combined with articular cartilage extracellular matrix (ACECM) scaffold for long term (3, 6 months) cartilage repair. Results: The enriched CD146+ ADSCs showed a high expression of stem cell and pericyte markers, good viability, and immune characteristics to avoid allogeneic rejection. Gene and protein expression profiles revealed that the CD146+ ADSCs had different cellular functions especially in regulation inflammation. In a rat model, CD146+ ADSCs showed a better inflammation-modulating property in the early stage of intra-articular injections. Importantly, CD146+ ADSCs exhibited good biocompatibility with the ACECM scaffold and the CD146+ cell-scaffold composites produced less subcutaneous inflammation. The combination of CD146+ ADSCs with ACECM scaffold can promote better cartilage regeneration in the long term. Conclusion: Our data elucidated the function of the CD146+ ADSC subpopulation, established their role in promoting cartilage repair, and highlighted the significance of cell subpopulations as a novel therapeutic for cartilage regeneration.

4.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(8): 1011-1018, 2019 Aug 15.
Artigo em Chinês | MEDLINE | ID: mdl-31407562

RESUMO

Objective: To manufacture a poly (lactic-co-glycolic acid) (PLGA) scaffold by low temperature deposition three-dimensional (3D) printing technology, prepare a PLGA/decellularized articular cartilage extracellular matrix (DACECM) cartilage tissue engineered scaffold by combining DACECM, and further investigate its physicochemical properties. Methods: PLGA scaffolds were prepared by low temperature deposition 3D printing technology, and DACECM suspensions was prepared by modified physical and chemical decellularization methods. DACECM oriented scaffolds were prepared by using freeze-drying and physicochemical cross-linking techniques. PLGA/DACECM oriented scaffolds were prepared by combining DACECM slurry with PLGA scaffolds. The macroscopic and microscopic structures of the three kinds of scaffolds were observed by general observation and scanning electron microscope. The chemical composition of DACECM oriented scaffold was analyzed by histological and immunohistochemical stainings. The compression modulus of the three kinds of scaffolds were measured by biomechanical test. Three kinds of scaffolds were embedded subcutaneously in Sprague Dawley rats, and HE staining was used to observe immune response. The chondrocytes of New Zealand white rabbits were isolated and cultured, and the three kinds of cell-scaffold complexes were prepared. The growth adhesion of the cells on the scaffolds was observed by scanning electron microscope. Three kinds of scaffold extracts were cultured with L-929 cells, the cells were cultured in DMEM culture medium as control group, and cell counting kit 8 (CCK-8) was used to detect cell proliferation. Results: General observation and scanning electron microscope showed that the PLGA scaffold had a smooth surface and large pores; the surface of the DACECM oriented scaffold was rough, which was a 3D structure with loose pores and interconnected; and the PLGA/DACECM oriented scaffold had a rough surface, and the large hole and the small hole were connected to each other to construct a vertical 3D structure. Histological and immunohistochemical qualitative analysis demonstrated that DACECM was completely decellularized, retaining the glycosaminoglycans and collagen typeⅡ. Biomechanical examination showed that the compression modulus of DACECM oriented scaffold was significantly lower than those of the other two scaffolds ( P<0.05). There was no significant difference between PLGA scaffold and PLGA/DACECM oriented scaffold ( P>0.05). Subcutaneously embedded HE staining of the three scaffolds showed that the immunological rejections of DACECM and PLGA/DACECM oriented scaffolds were significantly weaker than that of the PLGA scaffold. Scanning electron microscope observation of the cell-scaffold complex showed that chondrocytes did not obviously adhere to PLGA scaffold, and a large number of chondrocytes adhered and grew on PLGA/DACECM oriented scaffold and DACECM oriented scaffold. CCK-8 assay showed that with the extension of culture time, the number of cells cultured in the three kinds of scaffold extracts and the control group increased. There was no significant difference in the absorbance ( A) value between the groups at each time point ( P>0.05). Conclusion: The PLGA/DACECM oriented scaffolds have no cytotoxicity, have excellent physicochemical properties, and may become a promising scaffold material of tissue engineered cartilage.


Assuntos
Cartilagem Articular , Tecidos Suporte , Animais , Células Cultivadas , Matriz Extracelular , Glicolatos , Glicóis , Ácido Láctico , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Impressão Tridimensional , Coelhos , Ratos , Ratos Sprague-Dawley
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 223: 117355, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31306966

RESUMO

In this paper, ratiometric imaging of lysosomal HOCl was realized with a molecular probe (CR-Ly) based on fluorescence resonance energy transfer by using coumarin as the donor and rhodamine as acceptor. CR-Ly showed high sensitivity and fast response to HOCl. Moreover, CR-Ly exhibited excellent selectivity and sensitivity for HOCl over other biologically relevant species. Furthermore, it was successfully utilized to image the endogenous HOCl with low cytotoxity. And CR-Ly was capable of targeting lysosomes and monitoring lysosomal hypochlorous acid changes owing to the presence of the morpholine moiety. We believe that probe CR-Ly would be helpful to further research on the HOCl-associated diseases in lysosomes.

6.
Food Chem ; 293: 169-177, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151598

RESUMO

Antioxidant molecules in honey contributed to various biological effects, but antioxidant components markers in honey are required to be investigated further. Phenolic compounds, flavonoids and free amino acids were analyzed using UPLC-MS/MS and HPLC-FLD from 39 honey samples, in which fennel honey was firstly investigated. Based on the quantitative composition-activity relationship, the cellular antioxidant activity (CAA) assay of various honeys is closely related with the interaction of some phenolic compounds (isoferulic acid, 3,4-dihydroxy benzoic acid, 4-hydroxy benzoic acid, chlorogenic acid, caffeic acid, gallic acid, cryptochlorogenic acid, p-coumaric acid, salicylic acid), flavonoids (isosakuranetin, sakuranetin, pinocembrin, vitexin, taxifolin, galangin, luteolin, chrysin) and free amino acids (Tyr, Gly, Ile, Glu, Val, Phe, Leu, Asp, His, Pro, Ala). The results would be beneficial for the understanding of the nutritional values, exploitation and utilization of honeys with different floral origins, further contributable to the market development and consumption choice of honey.


Assuntos
Antioxidantes/análise , Mel/análise , Aminoácidos/análise , Aminoácidos/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Flavonoides/química , Análise dos Mínimos Quadrados , Fenóis/análise , Fenóis/química , Espectrometria de Massas em Tandem
7.
Infect Dis Poverty ; 8(1): 49, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31200765

RESUMO

BACKGROUND: Infectious diseases encompass a large spectrum of diseases that threaten human health, and coinfection is of particular importance because pathogen species can interact within the host. Currently, the antagonistic relationship between different pathogens during concurrent coinfections is defined as one in which one pathogen either manages to inhibit the invasion, development and reproduction of the other pathogen or biologically modulates the vector density. In this review, we provide an overview of the phenomenon and mechanisms of antagonism of coinfecting pathogens involving parasites. MAIN BODY: This review summarizes the antagonistic interaction between parasites and parasites, parasites and viruses, and parasites and bacteria. At present, relatively clear mechanisms explaining polyparasitism include apparent competition, exploitation competition, interference competition, biological control of intermediate hosts or vectors and suppressive effect on transmission. In particular, immunomodulation, including the suppression of dendritic cell (DC) responses, activation of basophils and mononuclear macrophages and adjuvant effects of the complement system, is described in detail. CONCLUSIONS: In this review, we summarize antagonistic concurrent infections involving parasites and provide a functional framework for in-depth studies of the underlying mechanisms of coinfection with different microorganisms, which will hasten the development of promising antimicrobial alternatives, such as novel antibacterial vaccines or biological methods of controlling infectious diseases, thus relieving the overwhelming burden of ever-increasing antimicrobial resistance.

8.
Nanoscale ; 11(21): 10229-10238, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31049502

RESUMO

Ultrasensitive and flexible pressure sensors that can perceive and respond to environmental stimuli have attracted considerable attention due to their potential applications in wearable electronics and electronic skin devices. Here, we report a simple and low-cost strategy to fabricate high-performance pressure sensors via constructing a unique conductive/insulating/conductive sandwich-like porous structure (SPS). Interpenetration of the conductive graphene network throughout the porous insulating interlayer produces a highly efficient transition from the non-conductive to the conductive state. Consequently, the SPS sensors exhibit an extreme resistance-switching behavior (resistance change of >105 at 30 kPa), high sensitivity (∼0.67 kPa-1, <1.5 kPa), fast response/recovery time (∼10 and ∼16 ms) and outstanding mechanical stability. Such SPS pressure sensors are applicable for detecting various mechanical deformation modes (press, bend and torsion) and different stress/strain levels (from gait feature, finger/wrist/elbow movement to breathing monitoring and real-time pulse wave), providing a new concept of device design for wearable electronic applications.

9.
Wei Sheng Yan Jiu ; 48(2): 284-288, 2019 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-31133109

RESUMO

OBJECTIVE: A new method for the determination of 16 amino acids in Hulless barley which were planted in the Tibetan plateau of China was established by the amino acid analyzer(AAA), and the amino acid was graded. METHODS: The samples were subjected to hydrolysis by the hydrochloric acid solution containing 0. 05% thioglycolic acid, and were carried out by AAA and hydrolyzed amino acid column PH(4. 6 mm×60 mm, 3 µm). The external standard method was used for quantitative analysis. RESULTS: This hydrolysis pretreatment process could effectively prevent oxidation of methionine. The recoveries were 93. 2%-96. 7%, and the relative standard deviations were no more than 2. 9%(n=6). As the cereal-restricted amino acid, Hulless barley restricted amino acid lysine was the content of up to 0. 367 g/100 g, and the lysine score(AAS) was 62. 4, which was better than the corresponding scores of wheat, glutinous rice, corn and millet. CONCLUSION: The method is accurate, and has good repeatability which could meet the requirements for determination of 16 amino acids in Hulless barley.


Assuntos
Aminoácidos/análise , Hordeum/química , China , Hidrólise , Zea mays
10.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(5): 628-633, 2019 May 15.
Artigo em Chinês | MEDLINE | ID: mdl-31090359

RESUMO

Objective: Electrospinning technique was used to manufacture polycaprolactone (PCL)/collagen typeⅠ nanofibers orientated patches and to study their physical and chemical characterization, discussing their feasibility as synthetic patches for rotator cuff repairing. Methods: PCL patches were prepared by electrospinning with 10% PCL electrospinning solution (control group) and PCL/collagen typeⅠorientated nanofibers patches were prepared by electrospinning with PCL electrospinning solution with 25% collagen type Ⅰ(experimental group). The morphology and microstructure of the two patches were observed by gross and scanning electron microscopy, and the diameter and porosity of the fibers were measured; the mechanical properties of the patches were tested by uniaxial tensile test; the composition of the patches was analyzed by Fourier transform infrared spectroscopy; and the contact angle of the patch surface was measured. Two kinds of patch extracts were co-cultured with the third generation of rabbit tendon stem cells. Cell counting kit 8 (CCK-8) was used to detect the toxicity and cell proliferation of the materials. Normal cultured cells were used as blank control group. Rabbit tendon stem cells were co-cultured with the two patches and stained with dead/living cells after 3 days of in vitro culture, and laser confocal scanning microscopy was used to observe the cell adhesion and activity on the patch. Results: Gross and scanning electron microscopy showed that the two patch fibers were arranged in orientation. The diameter of patch fibers in the experimental group was significantly smaller than that in the control group ( t=26.907, P=0.000), while the porosity in the experimental group was significantly larger than that in the control group ( t=2.506, P=0.032). The tensile strength and Young's modulus of the patch in the experimental group were significantly higher than those in the control group ( t=3.705, P=0.029; t=4.064, P=0.034). Infrared spectrum analysis showed that PCL and collagen type Ⅰ were successfully mixed in the experimental group. The surface contact angle of the patch in the experimental group was (73.88±4.97)°, which was hydrophilic, while that in the control group was (128.46±5.10) °, which was hydrophobic. There was a significant difference in the surface contact angle between the two groups ( t=21.705, P=0.002). CCK-8 test showed that with the prolongation of culture time, the cell absorbance ( A) value increased gradually in each group, and there was no significant difference between the experimental group and the control group at each time point ( P>0.05). Laser confocal scanning microscopy showed that rabbit tendon stem cells could adhere and grow on the surface of both patches after 3 days of culture. The number of cells adhered to the surface of the patches in the experimental group was more than that in the control group, and the activity was better. Conclusion: PCL/ collagen type Ⅰ nanofibers orientated patch prepared by electrospinning technology has excellent physical and chemical properties, cell adhesion, and no cytotoxicity. It can be used as an ideal scaffold material in tendon tissue engineering for rotator cuff repair in the future.


Assuntos
Nanofibras , Manguito Rotador , Tecidos Suporte , Animais , Proliferação de Células , Colágeno , Poliésteres , Coelhos , Engenharia Tecidual
11.
J Cancer Res Ther ; 15(2): 329-335, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30964106

RESUMO

Aim: The aim of this study was to investigate the effect of microRNA-1224-5p (miR-1224-5p) on tumor endothelial cells (TECs) of human hepatocellular carcinoma (HCC). Subjects and Methods: Oligonucleotides were chemically synthesized and transfected into TECs using Lipofectamine 2000. TECs were divided into three groups, namely a control (CON) group without transfection, a negative control (NC) group transfected with negative control oligonucleotides and green fluorescent protein (GFP), and a micro-up (MU) group transfected with miR-1224-5p mimic and GFP. The expression of miR-1224-5p was quantified via quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The proliferation of TECs was detected using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and the optical density value at 490 nm was measured after every 24 h. Apoptosis was detected via flow cytometry using a 7-aminoactinomycin/APC Annexin V kit. The migration and invasion of TECs were detected using transwell assay. The tube formation ability was evaluated using the tube formation assay. Results: Oligonucleotides were successfully transduced into TECs, and the expression of miR-1224-5p was specifically upregulated. The results of qRT-PCR analysis showed that the expression of miR-1224-5p was significantly upregulated in the MU group (2-ΔΔCt = 3.27 ± 0.15) than in the CON group (2-ΔΔCt = 1) and NC group (2-ΔΔCt = 1.08 ± 0.11) (P < 0.01). The results of MTT assay showed that the cell proliferation was significantly inhibited in the MU group at four time points than in the CON and NC groups (P < 0.01). Flow cytometry analysis revealed the significant increase in apoptosis of cells from the MU group (19.29% ± 0.95%) than those from the CON (8.73% ± 0.64%) and NC (9.51% ± 0.56%) (P < 0.01) groups. The migration ability was significantly inhibited in MU group (51.0 ± 3.6) as compared with CON (77.7 ± 2.5) and NC (79.2 ± 3.5) groups (P < 0.01). The invasion ability of TECs was significantly inhibited in MU group (9.8 ± 1.3) than in CON (15.8 ± 0.8) and NC (15.4 ± 0.9) groups (P < 0.01). The ability of tube formation of TECs was completely inhibited in MU group but remained unaffected in CON and NC groups. Conclusions: miR-1224-5p may serve as a potential tumor suppressor in HCC. Upregulation in miR-1224-5p expression may decrease proliferation, induce apoptosis, inhibit migration and invasion, and suppress tube formation in TECs of human HCC.


Assuntos
Carcinoma Hepatocelular/genética , Células Endoteliais/metabolismo , Neoplasias Hepáticas/genética , MicroRNAs/genética , Apoptose , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Humanos , Neoplasias Hepáticas/patologia , Neovascularização Patológica/genética , Transfecção
12.
Andrologia ; 51(6): e13285, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31006889

RESUMO

The present study was designed to investigate the therapeutic effect of bone marrow MSC-derived factors on gonadotropic toxicity induced by busulfan in vivo. The conditioned media (CM) was obtained from MSCs in serum-free incubation for 48 hr and concentrated ~25-fold by ultrafiltration. The CM of HEK 293 cells was treated as control (293-CM). MSC-CM was injected into busulfan mice via caudal veins after 1 day of busulfan treatment for 2 weeks (200 µl per dose/twice weekly). Compared to the 293-CM group, testicular injury was delayed in MSC-CM group, including reduced vacuolations of cells in the basal compartment of the seminiferous epithelium and detachment of cells from basement membrane. Apoptotic spermatogenic cells were significantly decreased in MSC-CM group (p ï¼œ 0.05). Interesting N-cadherin,ICAM-1 and P-cadherin expressions significantly increased in MSC-CM group, while occludin, ZO-1 and connexin 43 expressions showed no difference among MSC-CM, 293-CM and busulfan groups. Present results suggest MSC-secreted factors protect spermatogenesis impairment after busulfan treatment by reducing the apoptosis of spermatogenic cells and enhancing intercellular adhesion molecule expressions.

13.
Pain Res Manag ; 2019: 9017931, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30863475

RESUMO

Chronic postsurgical pain (CPSP) is a chronic pain state that is difficult to be treated clinically. A series of complicated changes have been produced from nociceptive stimulation to the occurrence and development of postsurgical pain. Many mechanisms remain unclear. In order to study the role of intercellular gap junctions in inducing inflammatory microenvironment at the beginning of nociceptor after operation, the model of skin/muscle incision and retraction (SMIR) was established. We observed the changes of the expression of exchange proteins directly activated by cAMP-1 (Epac1) and p120 catenin (p120), the quantities of macrophages and endothelial cells, vascular endothelial permeability, and mechanical withdrawal threshold (MWT). It was found that macrophages and endothelial cells were functionally coupled through Epac1-p120. Adhesive linkage disorder remodeled the chronic, inflammatory, and eutrophic microenvironment at the beginning of nociceptor after operation through macrophages, endothelial cells, and endothelial paracellular pathways. It might be an early event and a key step in peripheral sensitization of CPSP. The expression of p120 in muscle tissue around the incision might become a prognostic marker for the conversion of acute postsurgical pain into CPSP. Targeted intervention of Epac1-p120 might be a clinical strategy for inhibiting the conversion of acute postsurgical pain into CPSP.


Assuntos
Cateninas/metabolismo , Dor Crônica/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Dor Pós-Operatória/metabolismo , Animais , Masculino , Ratos , Ratos Sprague-Dawley
14.
Ecotoxicol Environ Saf ; 172: 423-431, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30735974

RESUMO

The photocatalytic performance of layered double hydroxides (LDH) is usually confined to the slow interface mobility and high recombination rate of photogenerated electron-hole pairs in material. To overcome the low photocatalytic efficiency, novel Ag2O/Ag decorated LDH (LDH-Ag2O/Ag) was successfully synthesized by depositing Ag2O on the surface of LDH and then converted to Ag° nanoparticles in the right position after heat treatment. The as-synthesized LDH-Ag2O/Ag composites were characterized by Powder X-ray diffraction (XRD), Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-visible diffuse reflectance spectra (UV-vis DRS), photoluminescence spectra (PL) and transient photocurrent (TPC) analysis. Compared with virgin LDH, the photocatalytic activities of LDH-Ag2O/Ag composites were enhanced significantly. The optimum photocatalytic efficiency of LDH-Ag10 (0.0184 min-1) was nearly 46 times higher than that of virgin LDH (0.0004 min-1). The result of active species trapping experiments indicated that •OH, h+, and •O2- have an effect on the TC degradation, where •OH played the predominant role during the photocatalytic process. The possible photocatalytic mechanisms involving the charge transfer pathway and reactive species generation during the process of TC degradation were also discussed. The improved photocatalytic activity of LDH-Ag2O/Ag could be attributed to the synergetic effect between LDH and Ag2O/Ag that extended visible light range and reduced photogenerated charge carriers recombination.


Assuntos
Luz , Óxidos/química , Compostos de Prata/química , Tetraciclina/química , Antibacterianos/química , Catálise , Hidróxidos/química , Microscopia Eletrônica de Transmissão , Espectroscopia Fotoeletrônica , Difração de Raios X
15.
J Agric Food Chem ; 67(8): 2235-2244, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30724068

RESUMO

To explore the regulatory factor of light quality affecting exopolysaccharide (EPS) production, transcriptome analysis of Nostoc flagelliforme cells exposed to red light (R), blue light (B), and mixed light (B/R = 15:7) (BR) with white fluorescent light as control was performed. The differentially expressed genes mainly enriched in carbohydrate metabolism and energy metabolism. Significant enrichment in the oxidation-reduction process and energy metabolism indicated that intracellular redox homeostasis was disrupted. An assay of reactive oxygen species (ROS) and malondialdehyde contents demonstrated light quality induced oxidative stress. To illustrate the relationship between ROS level and EPS accumulation, the effects of the exogenous addition of ROS scavenger N-acetyl cysteine and inducer H2O2 on the oxidation-reduction level and EPS production were compared. The results revealed that light quality regulated EPS biosynthesis via the intracellular ROS level directly other than oxidative stress. Understanding such relationships might provide guidance for efficient EPS production to regulate the intracellular redox level.


Assuntos
Nostoc/metabolismo , Polissacarídeos Bacterianos/biossíntese , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Meios de Cultura/metabolismo , Peróxido de Hidrogênio/metabolismo , Luz , Nostoc/genética , Nostoc/crescimento & desenvolvimento , Nostoc/efeitos da radiação , Oxirredução , Estresse Oxidativo/efeitos da radiação
16.
Int J Mol Sci ; 20(1)2019 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-30626061

RESUMO

As a promising energy plant for biodiesel, Jatropha curcas is a tropical and subtropical shrub and its growth is affected by one of major abiotic stress, chilling. Therefore, we adopt the phosphoproteomic analysis, physiological measurement and ultrastructure observation to illustrate the responsive mechanism of J. curcas seedling under chilling (4 °C) stress. After chilling for 6 h, 308 significantly changed phosphoproteins were detected. Prolonged the chilling treatment for 24 h, obvious physiological injury can be observed and a total of 332 phosphoproteins were examined to be significantly changed. After recovery (28 °C) for 24 h, 291 phosphoproteins were varied at the phosphorylation level. GO analysis showed that significantly changed phosphoproteins were mainly responsible for cellular protein modification process, transport, cellular component organization and signal transduction at the chilling and recovery periods. On the basis of protein-protein interaction network analysis, phosphorylation of several protein kinases, such as SnRK2, MEKK1, EDR1, CDPK, EIN2, EIN4, PI4K and 14-3-3 were possibly responsible for cross-talk between ABA, Ca2+, ethylene and phosphoinositide mediated signaling pathways. We also highlighted the phosphorylation of HOS1, APX and PIP2 might be associated with response to chilling stress in J. curcas seedling. These results will be valuable for further study from the molecular breeding perspective.


Assuntos
Temperatura Baixa , Jatropha/metabolismo , Jatropha/fisiologia , Fosfoproteínas/metabolismo , Proteínas de Plantas/metabolismo , Proteômica/métodos , Plântula/metabolismo , Estresse Fisiológico , Motivos de Aminoácidos , Sequência de Aminoácidos , Ontologia Genética , Jatropha/ultraestrutura , Anotação de Sequência Molecular , Fosfopeptídeos/metabolismo , Fosfoproteínas/química , Fosforilação , Folhas de Planta/metabolismo , Folhas de Planta/ultraestrutura , Proteínas de Plantas/química , Mapas de Interação de Proteínas , Plântula/anatomia & histologia , Plântula/fisiologia , Plântula/ultraestrutura
17.
Anal Chim Acta ; 1052: 124-130, 2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30685030

RESUMO

In this paper, we synthesized a ratiometric fluorescence probe (IRh-Ly) for lysosomal hypochlorous acid (HOCl) by adopting a through-bond energy transfer (TBET) strategy on rhodamine-imidazo[1,5-a]pyridine platform. IRh-Ly showed brilliant selectivity, rapid response for HOCl. The probe also exhibited high sensitivity with the detection limit calculated to be 10.2 nM. Moreover, we demonstrated its successful application of detecting lysosomal HOCl in living RAW264.7 cells. Notably, the morpholine was integrated into the fluorescent probe IRh-Ly and the results revealed that IRh-Ly could target lysosome and detect the lysosomal HOCl. All the unique features made IRh-Ly particularly suitable for ratiometric HOCl detection and bio-imaging applications.


Assuntos
Transferência de Energia , Corantes Fluorescentes/metabolismo , Ácido Hipocloroso/metabolismo , Lisossomos/metabolismo , Animais , Camundongos , Morfolinas/química , Morfolinas/metabolismo , Imagem Óptica , Células RAW 264.7
18.
Tissue Eng Part B Rev ; 25(3): 187-201, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30608012

RESUMO

IMPACT STATEMENT: This article primarily reviews the applications of three-dimensional printing in cartilage tissue engineering at different anatomical locations and summarizes their strengths and limitations. In addition, we believe that four-dimensional concept and biological microenvironment should not be ignored for functional cartilage regeneration in the future. Finally, we hope the review provide scientist inspiration with constructing anisotropic tissue-engineered organ or tissue.

19.
Anal Chim Acta ; 1046: 185-191, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30482298

RESUMO

A rhodamine B-based derivative (RL1) was developed as a specific fluorescent probe for HOCl. Meanwhile, morpholine moiety was introduced into the probe. It was found that the probe could display highly selective, sensitive and naked-eye detection upon the addition of HOCl. And the detection limit (LOD) was calculated to be as low as 2.8 nM. Furthermore, cellular confocal microscopic studies revealed that the introduction of morpholine moiety realized the lysosome-targeting capability. Moreover, RL1 was successfully applied for the imaging of endogenous HOCl with low cytotoxicity. Therefore, all the desirable features made probe RL1 particularly suitable for HOCl detection in aqueous buffer solution samples as well as the bio-imaging applications.


Assuntos
Corantes Fluorescentes/química , Ácido Hipocloroso/análise , Lisossomos/química , Rodaminas/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Corantes Fluorescentes/farmacologia , Limite de Detecção , Camundongos , Microscopia Confocal , Microscopia de Fluorescência , Estrutura Molecular , Imagem Óptica , Células RAW 264.7 , Rodaminas/farmacologia , Relação Estrutura-Atividade
20.
Wei Sheng Yan Jiu ; 47(5): 804-814, 2018 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-30593310

RESUMO

OBJECTIVE: To establish a method for the determination of five nucleosides, including adenosine( A), guanosine( G), cytidine( C), uridine( U), inosine( I), and five nucleotides, including cytidine monophosphate( CMP), uridine monophosphate( UMP), adenosin monophosphate( AMP), inosine monphosphate( IMP), guanosine monophosphate( GMP), from milk powder products by ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry( UPLCMS/MS). METHODS: After hydrolysis with warm water, the sample was deproteinated by25% acetic acid in water. The analysis was performed on a T3 column( 2. 1 mm × 100 mm, 1. 8 µm) and gradiently eluted using 0. 1% formic acid in both acetonitrile and water as the mobile phase. The samples were determined by mass spectrometry in the positive ion mode with the multiple reaction monitoring mode, quantified by the external standard method. RESULTS: Five kinds of nucleosides and five kinds of nucleotides were separated within ten minutes. IMP and GMP were linear in the concentration range of 10-1000 ng/m L, and theother nucleosides and nucleotides were linear in the concentration range of 5-1000 ng/m L. The limits of detection for five nucleasides and nucleatides were in the range of 0. 002-0. 150 mg/kg. Recoveries of five nucleasides and nucleatides at different levels were in ranges of 89%-121%, with the relative standard deviations were in ranges of 0. 91%-8. 84%( n = 6). CONCLUSION: This method is fast, accurate and sensitive and the preprocessing is simple, which can be used for determination of five nucleosides and five nuclestides in milk powder products effectively.


Assuntos
Leite , Nucleosídeos , Nucleotídeos , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Leite/química , Nucleosídeos/análise , Nucleotídeos/análise , Espectrometria de Massas em Tandem
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