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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 267(Pt 1): 120541, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34740004

RESUMO

Charge-transfer complexes (CTC) exhibit promising application in scientific field. A prototype CTC (TTF-TCNQ), formed by charge donating (tetrathiafulvalene) and charge accepting (tetracyanoquinodimethane) molecule, was systematically studied by Raman method. By combining Raman and synchrony X-ray diffraction (XRD), we investigated the high-pressure structures of TTF-TCNQ up to 15 GPa, and did not observe any first-order phase transition. Finally, a detailed evolution of structure for TTF-TCNQ, versus pressure, is provided, offering a new pathway to investigate the structural stability of CTC.


Assuntos
Nitrilas , Transição de Fase , Difração de Raios X
2.
BMC Plant Biol ; 21(1): 477, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34670492

RESUMO

BACKGROUND: Both underground rhizomes/buds and above-ground Moso bamboo (Phyllostachys heterocycla) shoots/culms/branches are connected together into a close inter-connecting system in which nutrients are transported and shared among each organ. However, the starch storage and utilization mechanisms during bamboo shoot growth remain unclear. This study aimed to reveal in which organs starch was stored, how carbohydrates were transformed among each organ, and how the expression of key genes was regulated during bamboo shoot growth and developmental stages which should lay a foundation for developing new theoretical techniques for bamboo cultivation. RESULTS: Based on changes of the NSC content, starch metabolism-related enzyme activity and gene expression from S0 to S3, we observed that starch grains were mainly elliptical in shape and proliferated through budding and constriction. Content of both soluble sugar and starch in bamboo shoot peaked at S0, in which the former decreased gradually, and the latter initially decreased and then increased as shoots grew. Starch synthesis-related enzymes (AGPase, GBSS and SBE) and starch hydrolase (α-amylase and ß-amylase) activities exhibited the same dynamic change patterns as those of the starch content. From S0 to S3, the activity of starch synthesis-related enzyme and starch amylase in bamboo rhizome was significantly higher than that in bamboo shoot, while the NSC content in rhizomes was obviously lower than that in bamboo shoots. It was revealed by the comparative transcriptome analysis that the expression of starch synthesis-related enzyme-encoding genes were increased at S0, but reduced thereafter, with almost the same dynamic change tendency as the starch content and metabolism-related enzymes, especially during S0 and S1. It was revealed by the gene interaction analysis that AGPase and SBE were core genes for the starch and sucrose metabolism pathway. CONCLUSIONS: Bamboo shoots were the main organ in which starch was stored, while bamboo rhizome should be mainly functioned as a carbohydrate transportation channel and the second carbohydrate sink. Starch metabolism-related genes were expressed at the transcriptional level during underground growth, but at the post-transcriptional level during above-ground growth. It may be possible to enhance edible bamboo shoot quality for an alternative starch source through genetic engineering.


Assuntos
Metabolismo dos Carboidratos/genética , Proteínas de Plantas/metabolismo , Poaceae/genética , Amido/metabolismo , Transcriptoma , Enzima Ramificadora de 1,4-alfa-Glucana/genética , Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo , Amilases/genética , Amilases/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/fisiologia , Brotos de Planta/ultraestrutura , Poaceae/crescimento & desenvolvimento , Poaceae/fisiologia , Poaceae/ultraestrutura , Rizoma/genética , Rizoma/crescimento & desenvolvimento , Rizoma/fisiologia , Rizoma/ultraestrutura
3.
ACS Omega ; 6(10): 6861-6870, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33748600

RESUMO

Alginate hydrogels have been widely used as excellent scaffold materials for implantation in biological systems because of their good biocompatibility. However, it is difficult to repair bone defects with these materials because of their poor mechanical properties. The aim of the present study was to fabricate a novel degradable alginate/palygorskite (PAL) composite hydrogel with good mechanical properties and investigate its potential for application in bone defect repair. The modified alginate-based hydrogel with increasing PAL content exhibited better mechanical properties than the original alginate hydrogel. In addition, the resulting composite hydrogel was thoroughly characterized by scanning electron microscopy (SEM). With increasing PAL content, the swelling ratio of the hydrogel increased in PBS (pH = 7.4). In vitro cytocompatibility was evaluated using bone marrow-derived mesenchymal stem cells (BMSCs) to confirm that the developed composite hydrogel was cytocompatible after 1, 3, and 7 days. All these results suggest that the developed composite hydrogel has great potential for bone tissue engineering applications. JWH133 is a selective agonist of cannabinoid receptor type 2 (CB2), which exerts dual anti-inflammatory and anti-osteoclastogenic effects. We co-cultured BMSCs with composite hydrogels loaded with JWH133, and analysis of proliferation and osteogenic differentiation indicated that the composite hydrogel loaded with JWH133 may enhance the osteogenic differentiation of rat BMSCs. Furthermore, we found that the composite hydrogel loaded with JWH133 inhibited osteoclast formation and the mRNA expression of osteoclast-specific markers. In summary, the developed composite hydrogel has a high drug-loading capacity, good biocompatibility, and strong potential as a drug carrier for treating osteoporosis by promoting osteoblast and inhibiting osteoclast formation and function.

4.
Food Chem ; 354: 129506, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33744665

RESUMO

Three heat-induced protein aggregates, beta-lactoglobulin fibrils (BLGF), nanoparticles (BLGN), and worm-like aggregates (BLGW) were chosen to probe the effect of disulfide bond and surface hydrophobicity on their gastric digestion behavior. Furthermore, the effect of polysaccharide (dextran sulfate sodium, DSS) on the digestion behavior of the protein aggregates was investigated. Results showed that disulfide bond had a mild restraint on the digestion extent (maximum up to 4.65%), especially when its content was below 1 mol/mol, while the surface hydrophobicity had a stronger influence (up to 8.96%), and there is definitive positive linear relationship between the surface hydrophobicity and the digestion extent. When incorporated with DSS, both the disulfide bond content and surface hydrophobicity of the aggregates decreased, consequently, and the digestion was impeded, confirming the stronger effect from the surface hydrophobicity. The digestion extent of the heat-induced protein aggregates could be modulated linearly by incorporation of polysaccharide.


Assuntos
Sulfato de Dextrana/química , Lactoglobulinas/química , Agregados Proteicos , Digestão , Ditiotreitol/química , Temperatura Alta , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Dodecilsulfato de Sódio/química
5.
Water Sci Technol ; 81(6): 1209-1220, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32597407

RESUMO

It has been proved that the nitrogen can be removed from the sediment in a sediment microbial fuel cell system (SMFCs), but the competition between nitrate and oxygen for electrons would be a key factor that would affect the removal efficiency, and its mechanism is not clear. Based on organic sediment fuel, an SMFC was constructed, and the influence of dissolved oxygen (DO) on nitrogen transformation and cathodic microbial communities was investigated. The results showed that the best total nitrogen removal efficiency of 60.55% was achieved at DO level of 3 mg/L. High DO concentration affected the removal efficiency through the electrons' competition with nitrate, while low DO concentration suppressed the nitrification. Comamonas, Diaphorobacter and Brevundimonas were the three dominant genera responsible for denitrification at DO concentration of 3 mg/L in this study. The establishment of SMFCs for nitrogen removal by regulating DO level would offer a promising method for sediment treatment.


Assuntos
Fontes de Energia Bioelétrica , Desnitrificação , Elétrons , Nitrificação , Nitrogênio , Oxigênio
6.
Int J Mol Med ; 45(5): 1563-1570, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32323752

RESUMO

The expression of anillin mRNA and protein is regulated in a cell cycle­dependent manner. However, the mechanism underlying this process is unclear. Previous studies analyzing the sequence of the 5'­untranslated region of anillin have unveiled several putative p53 binding sites. Therefore, the present study hypothesized that the anillin gene may be repressed by p53 and that the commonly observed mutation (or loss of function) of p53 may serve a role in this phenotype. Bioinformatic analysis of the anillin promoter region revealed potential p53 responsive elements. Of those identified, 2 were able to bind p53 protein, as determined via a chromatin immunoprecipitation assay. Although it was hypothesized that DNA damage and resultant p53 expression would repress anillin expression, the results revealed that anillin mRNA and protein expression levels were negatively regulated by DNA damage in the wild­type p53 cells, but not in the isogenic p53 null cells. Furthermore, DNA sequences encompassing the p53 binding site downregulated luciferase transgenes in a p53 dependent manner. Taken together, these data indicated that anillin was negatively regulated by p53 and that anillin overexpression observed in cancer may be a p53­mediated phenomenon. The data from the present study provided further evidence for the role of p53 in the biologically crucial process of cytokinesis.


Assuntos
Proteínas Contráteis/genética , Regiões Promotoras Genéticas/genética , Elementos de Resposta/genética , Proteína Supressora de Tumor p53/genética , Sítios de Ligação/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina/métodos , Dano ao DNA/genética , Regulação para Baixo/genética , Células HCT116 , Humanos , Luciferases/genética , Células MCF-7 , Mutação/genética , Ligação Proteica/genética
7.
BMC Musculoskelet Disord ; 20(1): 591, 2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31812161

RESUMO

BACKGROUND: Fibroblast-like synoviocytes (FLS) are essential cellular components in inflammatory joint diseases such as osteoarthritis (OA) and rheumatoid arthritis (RA). Despite the growing use of FLS isolated from OA and RA patients, a detailed functional and parallel comparison of FLS from these two types of arthritis has not been performed. METHODS: In the present study, FLS were isolated from surgically removed synovial tissues from twenty-two patients with OA and RA to evaluate their basic cellular functions. RESULTS: Pure populations of FLS were isolated by a sorting strategy based on stringent marker expression (CD45-CD31-CD146-CD235a-CD90+PDPN+). OA FLS and RA FLS at the same passage (P2-P4) exhibited uniform fibroblast morphology. OA FLS and RA FLS expressed a similar profile of cell surface antigens, including the fibroblast markers VCAM1 and ICAM1. RA FLS showed a more sensitive inflammatory status than OA FLS with regard to proliferation, migration, apoptosis, inflammatory gene expression and pro-inflammatory cytokine secretion. In addition, the responses of OA FLS and RA FLS to both the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-α) and the anti-inflammatory drug methotrexate (MTX) were also evaluated here. CONCLUSION: The parallel comparison of OA FLS and RA FLS lays a foundation in preparation for when FLS are considered a potential therapeutic anti-inflammatory target for OA and RA.


Assuntos
Artrite Reumatoide/cirurgia , Osteoartrite/cirurgia , Membrana Sinovial/patologia , Sinoviócitos/imunologia , Apoptose/imunologia , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Movimento Celular/imunologia , Proliferação de Células , Células Cultivadas , Citometria de Fluxo , Humanos , Hiperplasia/patologia , Metotrexato/farmacologia , Osteoartrite/imunologia , Osteoartrite/patologia , Cultura Primária de Células , Membrana Sinovial/citologia , Membrana Sinovial/imunologia , Sinoviócitos/efeitos dos fármacos , Sinoviócitos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
8.
Carbohydr Polym ; 224: 115170, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472872

RESUMO

The emulsification properties of the standard (STD), matured (EM2 and EM10) and fractionated gum arabic samples via phase separation induced molecular fractionation were investigated to find out how the content of arabinogalactan protein (AGP) complex affects the resulting emulsion properties. Phase separation and the accompanying molecular fractionation were induced by mixing with different hydrocolloids including hyaluronan (HA), carboxymethyl cellulose (CMC), and maltodextrin (MD). Increase of AGP content from 11 to 28% resulted in the formation of emulsions with relatively smaller droplet sizes and better stability. Further increase in the AGP content to 41% resulted in the formation of emulsions with larger droplets. In spite of the larger droplets sizes, these emulsions were extremely stable. In addition, the emulsions prepared with GA higher AGP content better stability in the presence of ethanol. The results indicate that AGP content plays a vital role in emulsion stability and droplet size.


Assuntos
Goma Arábica/química , Mucoproteínas/química , Emulsões , Etanol/química , Ácido Hialurônico/química , Proteínas de Plantas/química
9.
ACS Appl Mater Interfaces ; 11(12): 11936-11946, 2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30843685

RESUMO

Hydrophilic-hydrophobic core-shell microparticles are highly appealing for a variety of industrial applications (foods, pharmaceutics, cosmetics, biomedicines, etc.) owing to their unique properties of moisture resistance and controlled release. However, the fabrication of such structured microparticles proves to be nontrivial due to the difficulty in assembling two materials of distinctly different hydrophilicities and hydrophobicities. This paper reports a facile method to fabricate hydrophilic-hydrophobic core-shell microparticles using all-natural food-grade polysaccharides and proteins, based on a novel principle of gel-network-restricted antisolvent precipitation. Immersion of microgel beads prepared from hydrophilic polysaccharides (i.e., alginates, κ-carrageenan, agarose) into a hydrophobic protein solution (i.e., zein in 70% aqueous ethanol) enables slow and controllable antisolvent precipitation of a protein layer around the microbead surface, leading to the formation of a hydrophilic-hydrophobic core-shell structure. The method applies to various gelling systems and can easily tailor the particle size and shell thickness. The resulting freeze-dried microparticles demonstrate restricted swelling in water, improved moisture resistance, and sustained release of encapsulants, with great potential in applications such as protection of unstable and/or hygroscopic compounds and delivery and controlled release of drugs, bioactives, flavors, etc. The method is rather universal and can be extended to prepare more versatile core-shell structures using a large variety of hydrophilic and hydrophobic materials.

10.
Exp Ther Med ; 6(1): 216-222, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23935749

RESUMO

In the field of hip arthroplasties, the secondary fixation of the implants depends directly on the quality of the primary stability. A good acetabular fit and metaphyseal filling between the prostheses and implants improve the initial stabilization, and optimize the transmission of forces to the bone. A precise knowledge of the three-dimensional acetabular or femoral shape is essential to the selection of adapted implants. A total of 63 patients diagnosed with developmental dysplasia were analyzed by three-dimensional computed tomography (3DCT), and the preoperative radiographic and 3DCT images were used to assess the acetabular/femoral deformities and variations of the hips. All joints were classified as Crowe type I, and bilateral measurements were taken for 10 patients. The acetabular abnormalities were classified according to the type of deficiency and the section angles of the acetabulum, with 26 hips (36%) classified as an anterior deficiency, 13 hips (18%) as a posterior deficiency and 34 hips (46%) as a lateral deficiency. The femoral side deformities were divided into three types according to the anteversion angle of the femur. A gradual increase in anteversion angle led to secondary rotational anomalies, and a narrowing of the canal at the isthmus. A total of 35 hips (48%) were classified as an F1 type deficiency, femur anteversion angle (FAVA) <30°; 32 hips (44%) as F2-type, 30°≤ FAVA ≤40°, with mild abnormalities of the femoral canal rotation and the diameter of the isthmus; and 6 hips (8%) as F3 type, FAVA >40°, with significant abnormalities of the femoral canal rotation and the diameter of the isthmus. This novel classification for adult acetabular dysplasia may provide a useful guide for surgery, and enable an improved selection of a suitable prosthesis.

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