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1.
Ann Med Surg (Lond) ; 86(3): 1433-1440, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38463057

RESUMO

Background and objectives: Enhanced recovery after surgery (ERAS) recommends avoiding enteral nutrition (EN) due to undesirable sequelae such as pulmonary aspiration and infections. Not using of EN in nongastric resections under ERAS pathways is often successful. However, parenteral nutrition (PN) alone followed by early postoperative oral feeding in gastric cancer patients, recommended by the ERAS guidelines, has unclear benefit and is only adopted after gastric resection. This study aimed to compute the postoperative outcomes of EN and PN compared to those of the ERAS-recommended nutritional pathway. Our secondary objective was to compare postoperative complications between the two groups. Materials and methods: Of 173 gastrectomy patients, 116 patients were in the combined group (EN and PN), whereas 57 patients were in the PN alone group. Statistical analysis was performed with the Statistical Package for the Social Sciences (SPSS) version 26.0.0 software. The data were analyzed by one-way ANOVA, the independent sample t-test, or, in the case of several independent samples, by the Kruskal-Wallis test. Categorical data were analyzed by Pearson's χ2 test or Fisher's exact test. Results: The observed indices included C-reactive protein (CRP), platelet (PLT), white blood cells (WBC), hemoglobin (Hb), albumin, and PRE-albumin. The secondary outcomes included length of hospital stay (LOS), cost, incidence of pulmonary infection, and total incidence of infection. Conclusion: The combined mode of nutrition is feasible and is not associated with postoperative complications in gastric cancer patients under ERAS.

2.
ACS Appl Mater Interfaces ; 15(13): 16874-16881, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36942855

RESUMO

A high-quality ultrathin dielectric film is important in the field of microelectronics. We designed a composite structure composed of Al2O3/HfO2 with different Al2O3/HfO2 cycles prepared by atomic layer deposition (ALD) to obtain high-quality ultrathin (1-12 nm) dielectric films. Al2O3 protected HfO2 from interacting with the Si substrate and inhibited the crystallization of the HfO2 film. High permittivity material of HfO2 was adopted to guarantee the good insulating property of the composite film. We investigated the physical properties as well as the growth mode of the composite film and found that the film exhibited a layer growth mode. The water contact angle and grazing-incidence small-angle X-ray scattering analyses revealed that the film was formed physically at 3 nm, while the thickness of the electrically stable film was 10 nm from grazing-incidence wide-angle X-ray scattering and dielectric constant analyses. The composite film was applied as a dielectric layer in thin-film transistors (TFTs). The threshold voltage was decreased to 0.27 V compared to the organic field-effect transistor with the single HfO2 dielectric, and the subthreshold swing was as small as 0.05 V/dec with a carrier mobility of 49.2 cm2/V s. The off-current was as low as 10-11 A, and the on/off ratio was as high as 5.5 × 106. This ALD-prepared composite strategy provides a simple and practical way to obtain the high-quality dielectric film, which shows the potential application in the field of microelectronics.

3.
Nat Commun ; 14(1): 1710, 2023 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-36973277

RESUMO

Liver-resident natural killer cells, a unique lymphocyte subset in liver, develop locally and play multifaceted immunological roles. However, the mechanisms for the maintenance of liver-resident natural killer cell homeostasis remain unclear. Here we show that early-life antibiotic treatment blunt functional maturation of liver-resident natural killer cells even at adulthood, which is dependent on the durative microbiota dysbiosis. Mechanistically, early-life antibiotic treatment significantly decreases butyrate level in liver, and subsequently led to defective liver-resident natural killer cell maturation in a cell-extrinsic manner. Specifically, loss of butyrate impairs IL-18 production in Kupffer cells and hepatocytes through acting on the receptor GPR109A. Disrupted IL-18/IL-18R signaling in turn suppresses the mitochondrial activity and the functional maturation of liver-resident natural killer cells. Strikingly, dietary supplementation of experimentally or clinically used Clostridium butyricum restores the impaired liver-resident natural killer cell maturation and function induced by early-life antibiotic treatment. Our findings collectively unmask a regulatory network of gut-liver axis, highlighting the importance of the early-life microbiota in the development of tissue-resident immune cells.


Assuntos
Butiratos , Microbioma Gastrointestinal , Butiratos/farmacologia , Interleucina-18 , Fígado , Células Matadoras Naturais
4.
Artigo em Inglês | MEDLINE | ID: mdl-36636608

RESUMO

Background: Clinacanthus nutans (Burm.f.) Lindau (C. nutans) has been used in the therapy of hepatitis B (HB) and is effective; however, the mechanism of action has not been elucidated. Objective: To investigate the protective effects of C. nutans aqueous extract on the hepatitis B virus (HBV) mouse model based on correlation analysis between gut microbiota and liver metabolomics. Materials and Methods: We firstly constructed the animal model by high-pressure injection of pcDNA3.1(+)/HBV plasmid into the tail vein and treated it with C. nutans. The biomarkers and inflammatory cytokines of HB were detected by enzyme-linked immunosorbent assay and quantitative PCR; the Illumina-MiSeq platform was used for investigating gut microbiota; the LC-MS/MS method was utilized on screening liver tissue metabolites; multiomics joint analysis was performed using the R program. Results: Compared with the modeling group, C. nutans significantly decreased the expression levels of HBsAg, IL-1ß, TNF-α(P < 0.05) in the serum, and cccDNA (P < 0.05) in the liver tissues of mice. C. nutans dramatically reduced the ratio of Firmicutes and Bacteroidetes (P < 0.05) and significantly declined the proportion of Lactobacillaceae and Lactobacillus(P < 0.05), dramatically increasing the relative abundance of Bacteroidales_S24-7_group, Rikenellaceae, and Alistipes(P < 0.05); LC-MS/MS analysis results showed that C. nutans dramatically upregulate hippuric acid, L-histidine, trehalose, D-threitol, and stachyose and downregulate uridine 5'-diphosphate, cholic acid, trimethylamine N-oxide, CDP-ethanolamine, and phosphorylcholine (P < 0.05). The correlation analysis revealed that C. nutans affects the related metabolite levels of hippuric acid and cholic acid through the modulation of crucial bacteria (Alistipes) (P < 0.01), exerting specific anti-inflammatory effects. Conclusion: These results suggest that C. nutans exerts protective effects in HBV model mice, showing the therapeutic potential for anti-HBV infection.

5.
Nanomaterials (Basel) ; 12(6)2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35335766

RESUMO

Superhydrophobicity is the phenomenon of which the water contact angle (WCA) of droplets on a solid surface is greater than 150°. In the present paper, we prepare a superhydrophobic film with a structure similar to the surface of a lotus leaf, which is composed of polydimethylsiloxane (PDMS), zinc oxide (ZnO), a molecular sieve (MS) and 1,2,3,4,8,9,10,11,15,16,17,18,22,23,24,25-hexadecafluorophthalocyanine copper(II) (F16CuPc). The F16CuPc was used as the modifier to reduce the surface energy of the biomimetic micro-nanostructure. With the introduction of F16CuPc, the superhydrophobic properties of the surface were enhanced so that the WCA and water roll-off angle could reach 167.1° and 0.5°, respectively. Scanning electron microscopy, X-ray energy spectrometry, and X-ray photoelectron spectroscopy analyses verified that the enhanced superhydrophobic properties of the film were mainly attributed to the modification of F16CuPc. Finally, thermal, mechanical, and chemical stability studies, as well as the influences of UV and underwater immersion on the superhydrophobic film were investigated. This developed two-step fabrication method may be a potential direction for superhydrophobic surface fabrication due to its simple process, excellent superhydrophobic property, and favorable stability.

6.
Phytochemistry ; 162: 148-156, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30897352

RESUMO

Chlorogenic acids (CGA; including 5-caffeoylquinic acid and its regio-isomers) in Taraxacum antungense Kitag. have antioxidant and anti-inflammatory properties and exert other pharmacological effects. T. antungense hydroxycinnamoyl-CoA quinate hydroxycinnamoyl transferase (TaHQT)1 and TaHQT2, which belong to the BAHD acyltransferase family, are candidates for synthesizing 5-caffeoylquinic acid and that have not been extensively characterized. In this study, we cloned the TaHQT1 and TaHQT2 genes and analysed the properties of the expressed enzymes both in vitro and in vivo. Quantitative reverse transcription PCR analysis revealed that TaHQT1 was highly expressed in the root, whereas the strongest TaHQT2 expression was observed in T. antungense leaves. In Nicotiana benthamiana leaf cells, TaHQT1 and TaHQT2 were localized at the cell periphery as well as in the cytoplasm and nucleus. The 5-caffeoylquinic acid concentrations in T. antungense calli were reduced by TaHQT1 and TaHQT2 knockdown relative to the control. Conversely, inoculation of T. antungense plants tissues with recombinant TaHQT1 and TaHQT2 increased 5-caffeoylquinic acid levels in situ. These in vitro and in vivo findings demonstrate that both HQTs are involved in regulating 5-caffeoylquinic acid biosynthesis in T. antungense, which can be exploited to increase 5-caffeoylquinic acid production in plants for medicinal or other beneficial purposes.


Assuntos
Aciltransferases/genética , Aciltransferases/metabolismo , Regulação da Expressão Gênica de Plantas , Ácido Quínico/análogos & derivados , Taraxacum/genética , Taraxacum/metabolismo , Aciltransferases/química , Sequência de Aminoácidos , Espaço Intracelular/metabolismo , Cinética , Folhas de Planta/metabolismo , Transporte Proteico , Ácido Quínico/metabolismo , Taraxacum/citologia , Taraxacum/enzimologia
7.
Colloids Surf B Biointerfaces ; 160: 500-509, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29017145

RESUMO

It has been widely accepted that cell behaviors can be affected by multiple kinds of biomaterial stimulation signals. Although many literatures have focused on studying the multiple biomaterials stimulatory cues in affecting cellular behaviors, systematic studies on the effects of individual and combination of multiple biomaterials stimulatory cues in regulating cellular behaviors and their potential possible mechanisms have rarely been reported. We hypothesized that tissue engineering scaffolds with enhanced bioactivity can be designed if synergetic effects between different kinds of biomaterial stimulation cues in affecting cells behaviors can be found and applied. To prove our concept, in this study, electrospun nanofibers were used to provide structure cues and bioactive glass (BG) ion extracts were used to provide chemistry cues. The effects of single type of electrospun nanofiber structure cues, single type of BG chemical cues and combined application of the two types of stimulatory cues on behaviors of human dermal fibroblasts (HDFs) and human umbilical vein endothelial cells (HUVECs) were evaluated. Results showed that the nanostructure cues of electrospun nanofibers mainly affected cell morphology and cytoskeleton distribution while the chemistry cues of BG ion extracts played important roles in promoting cell proliferation. Both of the electrospun nanofiber structure and BG chemistry cues contributed to cell differentiation, including extracellular matrix synthesis of HDFs and vascularization of HUVECs. Interestingly, when the two kinds of stimulatory cues were applied together, obvious synergetic effects were observed as the combination of the two stimulatory cues showed the strongest stimulation effects on cell differentiation among all groups. Taken together, it is feasible to simultaneously apply two or more kinds of biomaterial stimulation signals to synergistically affect cell behaviors and enhance tissue regeneration, which is critical for instructing the design of tissue engineering scaffolds or biomaterial substrates with improved bioactivity.


Assuntos
Fibroblastos/citologia , Vidro/química , Células Endoteliais da Veia Umbilical Humana/citologia , Nanoestruturas/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Derme/citologia , Sinergismo Farmacológico , Fibroblastos/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Microscopia Eletrônica de Varredura , Nanofibras/química , Nanofibras/ultraestrutura , Nanoestruturas/ultraestrutura , Engenharia Tecidual/métodos , Alicerces Teciduais/química
8.
Acta Biomater ; 55: 249-261, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28377306

RESUMO

Biomaterials are only used as carriers of cells in the conventional tissue engineering. Considering the multi-cell environment and active cell-biomaterial interactions in tissue regeneration process, in this study, structural signals of aligned electrospun nanofibers and chemical signals of bioglass (BG) ionic products in cell culture medium are simultaneously applied to activate fibroblast-endothelial co-cultured cells in order to obtain an improved skin tissue engineering construct. Results demonstrate that the combined biomaterial signals synergistically activate fibroblast-endothelial co-culture skin tissue engineering constructs through promotion of paracrine effects and stimulation of gap junctional communication between cells, which results in enhanced vascularization and extracellular matrix protein synthesis in the constructs. Structural signals of aligned electrospun nanofibers play an important role in stimulating both of paracrine and gap junctional communication while chemical signals of BG ionic products mainly enhance paracrine effects. In vivo experiments reveal that the activated skin tissue engineering constructs significantly enhance wound healing as compared to control. This study indicates the advantages of synergistic effects between different bioactive signals of biomaterials can be taken to activate communication between different types of cells for obtaining tissue engineering constructs with improved functions. STATEMENT OF SIGNIFICANCE: Tissue engineering can regenerate or replace tissue or organs through combining cells, biomaterials and growth factors. Normally, for repairing a specific tissue, only one type of cells, one kind of biomaterials, and specific growth factors are used to support cell growth. In this study, we proposed a novel tissue engineering approach by simply using co-cultured cells and combined biomaterial signals. Using a skin tissue engineering model, we successfully proved that the combined biomaterial signals such as surface nanostructures and bioactive ions could synergistically stimulate the cell-cell communication in co-culture system through paracrine effects and gap junction activation, and regulated expression of growth factors and extracellular matrix proteins, resulting in an activated tissue engineering constructs that significantly enhanced skin regeneration.


Assuntos
Comunicação Celular , Células Endoteliais da Veia Umbilical Humana , Nanofibras , Pele Artificial , Pele , Cicatrização , Animais , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/transplante , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanofibras/química , Nanofibras/uso terapêutico , Pele/lesões , Pele/metabolismo , Pele/patologia
9.
Bioact Mater ; 2(1): 10-18, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29744406

RESUMO

Iron-matrix composites with calcium silicate (CS) bioceramic as the reinforcing phase were fabricated through powder metallurgy processes. The microstructures, mechanical properties, apatite deposition and biodegradation behavior of the Fe-CS composites, as well as cell attachment and proliferation on their surfaces, were characterized. In the range of CS weight percentages selected in this study, the composites possessed compact structures and showed differently decreased bending strengths as compared with pure iron. Immersion tests in simulated body fluid (SBF) revealed substantially enhanced deposition of CaP on the surfaces of the composites as well as enhanced degradation rates as compared with pure iron. In addition, the composite containing 20% CS showed a superior ability to stimulate hBMSCs proliferation when compared to pure iron. Our results suggest that incorporating calcium silicate particles into iron could be an effective approach to developing iron-based biodegradable bone implants with improved biomedical performance.

10.
Am J Transl Res ; 8(4): 1678-94, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27186292

RESUMO

Electrospun nanofibrous sheets get increasing attention in myocardial infarction (MI) treatment due to their good cytocompatibility to deliver transplanted stem cells to infarcted areas and due to mechanical characteristics to support damaged tissue. Cardiac extracellular matrix is essential for implanted cells since it provides the cardiac microenvironment. In this study, we hypothesized high concentrations of cardiac nature protein (NP), namely elastin and collagen, in hybrid polycaprolactone (PCL) electrospun nanofibrous sheets could be effective as cardiac-mimicking patch. Optimal ratio of elastin and collagen with PCL in electrospun sheets (80% NP/PCL) was selected based on cytocompatibility and mechanical characteristics. Bone-marrow (BM) c-kit(+) cells anchoring onto NP/PCL sheets exhibited increased proliferative capacity compared with those seeded on PCL in vitro. Moreover, we examined the improvement of cardiac function in MI mice by cell-seeded cardiac patch. Green Fluorescent Protein (GFP)-labeled BM c-kit(+) cells were loaded on 80% NP/PCL sheets which was transplanted into MI mice. Both 80% NP/PCL and c-kit(+)-seeded 80% NP/PCL effectively improved cardiac function after 4 weeks of transplantation, with reduced infarction area and restricted LV remodeling. C-kit(+)-seeded 80% NP/PCL was even superior to the 80% NP/PCL alone and both superior to PCL. GFP(+) cells were identified both in the sheets and local infarcted area where transplanted cells underwent cardiac differentiation after 4 weeks. To the best of our knowledge, this is the first report that sheets with high concentrations of nature proteins loaded with BM c-kit(+) cells might be a novel promising candidate for tissue-engineered cardiac patch to improve cardiac repair after MI.

11.
J Mater Chem B ; 2(34): 5492-5510, 2014 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32262184

RESUMO

This article presents an overview focusing on the structural control of electrospun membranes on a multilevel scale ranging from the morphology of single nanofibers to the packing and alignment of nanofibers and the patterns and shapes of fibrous scaffolds. The typical structures of electrospun membranes and the specific electrospinning strategies used to produce these structures are reviewed. In addition, potential applications of these controlled structures in tissue engineering and drug delivery are highlighted. Finally, this review concludes with a perspective on the challenges and future directions for the design and fabrication of electrospun scaffolds using controlled structures along with an investigation of the relationship between the structures of electrospun membranes and the cell and drug delivery behaviors.

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