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1.
Colloids Surf B Biointerfaces ; 245: 114262, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39303383

RESUMEN

Hydrogel-based tissue clearing technologies have shown significant promise for deep-tissue imaging and subcellular-level optical 3D reconstruction of whole organs. This study proposes a novel approach utilizing a deep eutectic solvent (DES) formulated with glucose and m-xylylene-diamine (MXDA) to create a highly efficient tissue-clearing hydrogel system named the passive hydrogel clearing system (PHCS). PHCS achieved efficient tissue clearing through a single-step tissue gelation process. The resulting hydrogel-tissue complex exhibited thermoreversible properties, transitioning into a sol state upon heating and vice versa upon cooling. Notably, PHCS enabled media embedding, facilitating immunofluorescence histopathology. Additionally, the system demonstrated compatibility with various fluorescent probes, particularly lipophilic dyes. Our study successfully employed PHCS for the reconstruction of vascular structures within the intestine, enabling the generation of a 3D pathology model. These findings suggest that PHCS is a promising novel method for fabricating hydrogels for tissue clearing and holds great potential for application as a mounting medium for morphological imaging.

2.
Carbohydr Polym ; 342: 122384, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39048195

RESUMEN

As the most abundant renewable resource, cellulose fibers are potential candidates for use in health-protective clothing. Herein, we demonstrate a novel strategy for preparing cellulose fiber with prominent antibacterial and antiviral performance by the synergistic effect of amino groups and sulfonic acid groups. Specifically, guanylated chitosan oligosaccharide (GCOS) and N-sulfopropyl chitosan oligosaccharide (SCOS) were synthesized and chemically grafted onto cellulose fibers (CFs) to endow the fibers with antibacterial and antiviral properties. Moreover, a compounding strategy was applied to make the fibers with simultaneously high antibacterial and antiviral activity, especially in short contact time. The bacteriostatic rate (against S. aureus: 95.81 %, against E. coli: 92.07 %, 1 h) of the compounded fibers improved substantially when a few GCOS-CFs were mixed with SCOS-CFs; especially, it was much higher than both the individual GCOS-CFs and SCOS-CFs. By contrast, the improvement of the antiviral properties was less dramatic; however, even a few SCOS-CFs was mixed, the antiviral properties increased pronouncedly. Although the electrostatic interaction between SCOS and GCOS can make the SCOS-GCOS mixture lose some extent of antibacterial activity, the long chains of cellulose restrain the electrostatic interaction between sulfonic and amino groups, leading to their synergistic action and eventually superior antibacterial and antiviral effects.


Asunto(s)
Antibacterianos , Antivirales , Celulosa , Quitosano , Escherichia coli , Staphylococcus aureus , Ácidos Sulfónicos , Antibacterianos/farmacología , Antibacterianos/química , Quitosano/química , Quitosano/farmacología , Antivirales/farmacología , Antivirales/química , Celulosa/química , Celulosa/farmacología , Celulosa/análogos & derivados , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Ácidos Sulfónicos/química , Oligosacáridos/química , Oligosacáridos/farmacología , Pruebas de Sensibilidad Microbiana , Sinergismo Farmacológico , Humanos
3.
Chem Eng J ; 464: 142588, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36992868

RESUMEN

The worldwide spread of COVID-19 has put a higher requirement for personal medical protective clothing, developing protective clothing with sustained antibacterial and antiviral performance is the priority for safe and sustaining application. For this purpose, we develop a novel cellulose based material with sustained antibacterial and antiviral properties. In the proposed method, the chitosan oligosaccharide (COS) was subjected to a guanylation reaction with dicyandiamide in the presence of Scandium (III) triflate; because of the relatively lower molecular weight and water solubility of the COS, GCOS (guanylated chitosan oligosaccharide) with high substitution degree (DS) could be successfully synthetized without acid application. In this instance, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the GCOS were only 1/8 and 1/4 of that of COS. The introduction of GCOS onto the fiber endowed the fiber with extremely high antibacterial and antiviral performance, showing 100% bacteriostatic rate against Staphylococcus aureus and Escherichia coli and 99.48% virus load reduction of bacteriophage MS2. More importantly, the GCOS modified cellulosic fibers (GCOS-CFs) exhibit excellent sustained antibacterial and antiviral properties; namely, 30 washing cycles had negligible effect on the bacteriostatic rate (100%) and inhibition rate of bacteriophage MS2 (99.0%). Moreover, the paper prepared from the GCOS-CFs still exhibited prominent antibacterial and antiviral activity; inferring that the sheeting forming, press, and drying process have almost no effect on the antibacterial and antiviral performances. The insensitive of antibacterial and antiviral activity to water washing (spunlace) and heat (drying) make the GCOS-CFs a potential material applicable in the spunlaced non-woven fabric production.

4.
Int J Biol Macromol ; 231: 123587, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36758766

RESUMEN

The worldwide outbreak of SARS-CoV-2 has attracted extensive attention to antibacterial and antivirus materials. Cellulose is the most potential candidate for the preparation of green, environmentally friendly antibacterial and antiviral materials. Herein, modified cellulosic fibers with sustained antibacterial and antiviral performance was prepared by introducing chitosan oligosaccharide onto the fibers. The two-step method is proved to be more effective than the one-step method for enhanced chitosan oligosaccharide loadings and antibacterial and antiviral activity. In this instance, the modified fibers with 61.77 mg/g chitosan oligosaccharide loadings can inhibit Staphylococcus aureus and Escherichia coli by 100 % after contacting with bacteria for 12 h and reduce the bacteriophage MS2 by 99.19 % after 1 h of contact. More importantly, the modified fibers have washing durable antibacterial and antiviral activity; the modified fibers have 100 % antibacterial and 98.38 % antiviral activity after 20 washing cycles. Benefiting from the excellent performance of the individual fibers, the paper prepared from the modified fibers show great antibacterial (100 %) and antiviral performance (99.01 %) and comparable mechanical strength. The modified fibers have potential applications in the manufacture of protective clothing and protective hygiene products.


Asunto(s)
COVID-19 , Quitosano , Humanos , Quitosano/farmacología , SARS-CoV-2 , Antibacterianos/farmacología , Escherichia coli , Oligosacáridos
5.
Int J Biol Macromol ; 228: 251-260, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36581021

RESUMEN

Recently, cellulose paper based triboelectric nanogenerators (CPTENGs) has gained widely attention due to the development of wearable, green and miniaturized electronic products. Modification of cellulose fibers or paper is a feasible method to improve the output performance of CPTENGs, however, the simple and effective routes to improve the triboelectric property of cellulose paper still remain a challenge. Herein, we report a simple method to prepare PEO/cellulose composite paper (PEO/CCP) via mixing polyethylene oxide (PEO) with cationic cellulose fibers. Benefiting from amino groups and PEO, the composite paper exhibits higher triboelectric positive property and triboelectric charge density, thereby endowing PEO/CCP based TENG with outstanding output performance. The voltage, current and power density peak values of PEO/CCP based TENG exhibited linear relationship with amino groups content; in this instance, the performance of the TENGs can be readily adjusted by the amino groups. The voltage, current and power density of PEO/CCP based TENG can be up to 222.1 V, 4.3 µA, and 217.3 mW•m-2, respectively. Moreover, a human-health detection device based on this TENG can monitor the physiological signals such as eye muscles, respiration, heart beat and wrist pulse, promising potentials for applications in human health-care.


Asunto(s)
Celulosa , Electrónica , Humanos , Frecuencia Cardíaca , Polietilenglicoles
6.
Hematology ; 27(1): 840-848, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35924822

RESUMEN

BACKGROUND: Acute myeloid leukemia (AML) is the most common acute blood malignancy in adults. The complicated and dynamic genomic instability (GI) is the most prominent feature of AML. Our study aimed to explore the prognostic value of GI-related genes in AML patients. METHODS: The mRNA data and mutation data were downloaded from the TCGA and GEO databases. Differential expression analyses were completed in limma package. GO and KEGG functional enrichment was conducted using clusterProfiler function of R. Univariate Cox and LASSO Cox regression analyses were performed to screen key genes for Risk score model construction. Nomogram was built with rms package. RESULTS: We identified 114 DEGs between high TMB patients and low TMB AML patients, which were significantly enriched in 429 GO terms and 13 KEGG pathways. Based on the univariate Cox and LASSO Cox regression analyses, seven optimal genes were finally applied for Risk score model construction, including SELE, LGALS1, ITGAX, TMEM200A, SLC25A21, S100A4 and CRIP1. The Risk score could reliably predict the prognosis of AML patients. Age and Risk score were both independent prognostic indicators for AML, and the Nomogram based on them could also reliably predict the OS of AML patients. CONCLUSIONS: A prognostic signature based on seven GI-related genes and a predictive Nomogram for AML patients are finally successfully constructed.


Asunto(s)
Leucemia Mieloide Aguda , Adulto , Inestabilidad Genómica , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Mutación , Nomogramas , Pronóstico
7.
Exp Gerontol ; 166: 111897, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35850279

RESUMEN

Ultraviolet radiation (UVB) can result in photodamage to the skin and can seriously threaten health, particularly in the elderly. Oxidative stress and the inflammatory response have been shown to play a significant role in the process. In a previous study, we isolated, purified and identified a polysaccharide from the extract of Dendrobium huoshanense (DHPW1). In this study we evaluated the effect of DHPW1 on ameliorating the UVB photodamage of human immortalized keratinocytes (HaCaT). Cell proliferation and cell scratch assays were used to evaluate the viability of the HaCaT treated with DHPW1, and a fluorescent probe and Western blot analysis were used to examine the production of reactive oxygen species (ROS) and the expression of proinflammatory factors IL-1ß, IL-6, and NF-κB(p65). The results show that, compared with the control group (UVB irradiation only), DHPW1 significantly improved the viability of UVB-irradiated HaCaT and enhanced the migration rate of the cell scratch after 24 h. The scratch-healing rate reached 90 % after 36 h. DHPW1 also significantly inhibited UVB-induced oxidative stress and expression of proinflammatory factors . Compared with the control group, the production of ROS decreased by 49.11 %, and the relative protein expression of IL-6 and NF-κB(p65) decreased by up to 13.30 % and 31.02 %, respectively. It is concluded that DHPW1 can significantly improve viability and wound closure rate of UVB-irradiated HaCaT. In addition, it can reduce the expression of IL-1 and IL-6 by inhibiting the transcription of NF-κB(p65), thereby reducing inflammation and oxidative stress in UVB-irradiated HaCaT.


Asunto(s)
FN-kappa B , Rayos Ultravioleta , Anciano , Línea Celular , Humanos , Interleucina-6/metabolismo , Queratinocitos , FN-kappa B/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Rayos Ultravioleta/efectos adversos
8.
Nanomaterials (Basel) ; 11(5)2021 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-33923021

RESUMEN

Cellulose paper has been functionalized by nanoparticles such as Ag nanoparticles, TiO2, and BaTiO3 for versatile applications including supercapacitor, sensors, photoactivity, and packaging. Herein, zinc oxide (ZnO) nanosheet-modified paper (ZnO@paper) with excellent antibacterial properties was fabricated via a mild ZnCl2-urea eutectic solvent. In this proposed method, cellulose fibers as the raw material for ZnO@paper were treated by an aqueous solvent of ZnCl2-urea; the crystalline region was destroyed and [ZnCl]+-based cations were adsorbed on the surface of cellulose fibers, facilitating more ZnO growth on ZnO@paper. A flexible paper-based triboelectric nanogenerator (P-TENG) was made of ZnO@paper paired with a PTFE film. The P-TENG presents high triboelectric output performance and antibacterial activity. For instance, the output voltage and current of the P-TENG were 77 V and 0.17 µA, respectively. ZnO@paper showed excellent antibacterial activity against E. coli and S. aureus, suggesting that a P-TENG can restrain and kill the bacteria during the working process. The results also indicated that ZnO could improve the surface roughness of cellulose paper, enhancing the output performance of a flexible P-TENG. In addition, the potential application of a P-TENG-based pressure sensor for determining human motion information was also reported. This study not only produced a high-performance P-TENG for fabricating green and sustainable electronics, but also provides an effective and novel method for ZnO@paper preparation.

9.
Hum Reprod ; 30(2): 380-91, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25505012

RESUMEN

STUDY QUESTION: How does the placenta protect the fetus from immune rejection by the mother? SUMMARY ANSWER: The placenta can produce IgG that is glycosylated at one of its Fab arms (asymmetric IgG; aIgG) which can interact with other antibodies and certain leukocytes to affect local immune reactions at the junction between the two genetically distinct entities. WHAT IS KNOWN ALREADY: The placenta can protect the semi-allogenic fetus from immune rejection by the immune potent mother. aIgG in serum is increased during pregnancy and returns to the normal range after giving birth. aIgG can react to antigens to form immune complexes which do not cause a subsequent immune effector reaction, including fixing complements, inducing cytotoxicity and phagocytosis, and therefore has been called 'blocking antibody'. STUDY DESIGN, SIZE, DURATION: Eighty-eight human placentas, four trophoblast cell lines (TEV-1, JAR, JEG and BeWo), primary culture of human placental trophoblasts and a gene knock-out mouse model were investigated in this study. PARTICIPANTS/MATERIALS, SETTING, METHODS: The general approach included the techniques of cell culture, immunohistochemistry, in situ hybridization, immuno-electron microscopy, western blot, quantitative PCR, protein isolation, glycosylation analysis, enzyme digestion, gene sequencing, mass spectrophotometry, laser-guided microdissection, enzyme-linked immunosorbent assay, pulse chase assay, double and multiple staining to analyze protein and DNA and RNA analysis at the cellular and molecular levels. MAIN RESULTS AND THE ROLE OF CHANCE: Three major discoveries were made: (i) placental trophoblasts and endothelial cells are capable of producing IgG, a significant portion of which is aberrantly glycosylated at one of its Fab arms to form aIgG; (ii) the asymmetrically glycosylated IgG produced by trophoblasts and endothelial cells can react to immunoglobulin molecules of human, rat, mouse, goat and rabbit at the Fc portion; (iii) asymmetrically glycosylated IgG can react to certain leukocytes in the membrane and cytoplasm, while symmetric IgG from the placenta does not have this property. LIMITATIONS, REASONS FOR CAUTION: Most of the experiments were performed in vitro. The proposed mechanism calls for verification in normal and abnormal pregnancy. WIDER IMPLICATIONS OF THE FINDINGS: This study identified a number of new phenomena suggesting that aIgG produced by the placenta would be able to react to detrimental antibodies and leukocytes and interfere with their immune reactions against the placenta and the fetus. This opens a new dimension for further studies on pregnancy physiology and immunology. Should the mechanism proposed here be confirmed, it will have a direct impact on our understanding of the physiology and pathology of human reproduction and offer new possibilities for the treatment of many diseases including spontaneous abortion, infertility and pre-eclampsia. It also sheds light on the mechanism of immune evasion in general including that of cancer.


Asunto(s)
Fragmentos Fab de Inmunoglobulinas/metabolismo , Inmunoglobulina G/metabolismo , Inmunomodulación , Modelos Inmunológicos , Placenta/inmunología , Adulto , Animales , Especificidad de Anticuerpos , Línea Celular , Células Cultivadas , Cruzamientos Genéticos , Endotelio Vascular/citología , Endotelio Vascular/inmunología , Endotelio Vascular/metabolismo , Endotelio Vascular/ultraestructura , Femenino , Humanos , Fragmentos Fab de Inmunoglobulinas/análisis , Inmunoglobulina G/análisis , Leucocitos/citología , Leucocitos/inmunología , Leucocitos/metabolismo , Leucocitos/ultraestructura , Ratones Noqueados , Microscopía Inmunoelectrónica , Placenta/citología , Placenta/metabolismo , Placenta/ultraestructura , Placentación , Embarazo , Trofoblastos/citología , Trofoblastos/inmunología , Trofoblastos/metabolismo , Trofoblastos/ultraestructura
10.
J Androl ; 29(6): 661-8, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18676361

RESUMEN

Curcumin, a naturally occurring compound, exhibits anticancer chemopreventive effects. We evaluated the effects and mechanisms of curcumin on the gene expression of prostate-specific antigen (PSA) in human androgen-sensitive prostatic carcinoma cells. LNCaP cells were used to determine the effect of curcumin on PSA expression. Quantitative PSA expression was assessed by reverse transcription polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), and immunoblot assay. The modulation of androgen, interlukin-6 (IL-6), and prostate-derived Ets factor (PDEF) on the PSA gene was identified by transient gene expression assay with the use of a PSA reporter vector. The effect of curcumin on the activity of androgen receptors was evaluated by electrophoretic mobility shift assay (EMSA). Immunoblot assays, RT-PCR, and ELISA indicated that curcumin treatments blocked the stimulation of methyltrienolone (R1881) and IL-6 on PSA gene expression in LNCaP cells. The effects of curcumin appear to be mediated via the androgen response element of PSA gene. Results from immunoblot assay and EMSA revealed the modulation of curcumin on the expression of androgen receptor and androgen receptor binding activity on androgen response element of PSA gene. Although overexpression of PDEF dramatically enhanced PSA gene expression, the results of immunoblot assays and transient reporter assays indicated that curcumin treatments did not affect the gene expression of PDEF. Curcumin inhibits R1881- and IL-6-mediated PSA gene expression in LNCaP cells through down-regulation of the expression and activity of androgen receptors.


Asunto(s)
Andrógenos/metabolismo , Antineoplásicos/farmacología , Curcumina/farmacología , Interleucina-6/metabolismo , Antígeno Prostático Específico/efectos de los fármacos , Neoplasias de la Próstata/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ensayo de Cambio de Movilidad Electroforética , Ensayo de Inmunoadsorción Enzimática , Expresión Génica/efectos de los fármacos , Humanos , Immunoblotting , Masculino , Antígeno Prostático Específico/biosíntesis , Proteínas Proto-Oncogénicas c-ets/biosíntesis , Proteínas Proto-Oncogénicas c-ets/efectos de los fármacos , Receptores Androgénicos/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección
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