Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 10 de 10
Filter
Add more filters










Publication year range
1.
Langmuir ; 38(31): 9587-9596, 2022 08 09.
Article in English | MEDLINE | ID: mdl-35881583

ABSTRACT

The advanced oxidation process of the photo-Fenton reaction can produce hydroxyl radicals with extremely strong oxidizing properties for the efficient and green degradation of various chemical and microbial pollutants. Herein, we report an approach to fabricating heterogeneous Fenton catalysts of ß-FeOOH nanorods on porous substrates triggered by mussel-inspired coatings of levodopa (3,4-dihydroxy-phenyl-l-alanine, l-DOPA) and polyethylenimine (PEI) for efficient photocatalytic dyes' degradation and sterilization. The l-DOPA-based coatings not only promote the formation and immobilization of ß-FeOOH nanorods on the porous substrates by strong coordination between catechol/carboxyl groups and Fe3+ but also improve the energy band structure of the Fenton catalysts through a valence band blue shift and band gap narrowing. The photo-Fenton catalysts prepared by the l-DOPA-based coatings exhibit high electron transport efficiency and improved utilization of sunlight. Only 2 h of mineralization is needed to fabricate these catalysts with excellent photocatalytic efficiency, in which the degradation efficiency of methylene blue can reach 99% within 30 min, whereas the sterilization efficiency of E. coli/S. aureus can reach 93%/94% within 20 min of the photo-Fenton reaction. Additionally, the prepared catalysts reveal a high photodegradation performance for various dyes including methylene blue, methyl blue, methyl orange, direct yellow, and rhodamine B. Furthermore, the catalysts retain high dye degradation efficiencies of above 90% after five photodegradation cycles, indicating cycling performance and good stability.


Subject(s)
Coloring Agents , Levodopa , Coloring Agents/chemistry , Escherichia coli , Hydrogen Peroxide/chemistry , Iron/chemistry , Methylene Blue , Porosity , Staphylococcus aureus , Sterilization
2.
J Mater Chem B ; 10(34): 6414-6424, 2022 08 31.
Article in English | MEDLINE | ID: mdl-35642602

ABSTRACT

The development of broad-spectrum anti-bacterial tough hydrogels without antibiotics remains a challenge in biomedical applications. In this study, we have synthesized a novel tough anti-bacterial complex hydrogel based on Cu2+ coordination. A swollen and weak poly(acrylamide-co-4-vinylbenzyl-(trihydroxymethyl-phosphonium)chloride) (P(AAm-co-VBzTHPC)) hydrogel was prepared by the radical copolymerization of AAm and VBzTHPC monomer solutions, followed by immersion in CuSO4 solution to coordinate with Cu2+ to form a strong and tough hydrogel. Fourier transform infrared (FTIR) spectra and X-ray photoelectron spectra (XPS) were used to characterize the coordination structure between phosphorus and oxygen atoms in the VBzTHPC monomer and copper ions. The water content and mechanical properties of the obtained hydrogel varied with gel composition. The prepared toughened hydrogel exhibited excellent anti-bacterial performance because of the introduction of copper ion coordination and the slow release of copper ions, with bacterial viability of 5.1% when the mole fraction of VBzTHPC was 10 mol%. Cell viability when cocultured with the toughened hydrogel was above 85% using the Cell Counting Kit-8 (CCK-8) method, indicating the good biocompatibility of the hydrogel. Compared with the control group experiment in vivo, this tough hydrogel can also promote wound healing, making it a promising candidate for wound dressing.


Subject(s)
Copper , Hydrogels , Bacteria , Bandages , Copper/chemistry , Copper/pharmacology , Hydrogels/chemistry , Hydrogels/pharmacology , Ions , Polyelectrolytes
3.
ACS Appl Mater Interfaces ; 13(48): 57000-57008, 2021 Dec 08.
Article in English | MEDLINE | ID: mdl-34816710

ABSTRACT

Porous surfaces have attracted tremendous interest for customized incorporation of functional agents on biomedical devices. However, the versatile preparation of porous structures on complicated devices remains challenging. Herein, we proposed a simple and robust method to fabricate "spongy skin" on diversified polymeric substrates based on non-solvent-induced phase separation (NIPS). Through the swelling and the subsequent phase separation process, interconnected porous structures were directly formed onto the polymeric substrates. The thickness and pore size could be regulated in the ranges of 5-200 and 0.3-0.75 µm, respectively. The fast capillary action of the porous structure enabled controllable loading and sustained release of ofloxacin and bovine albumin at a high loading dosage of 79.9 and 24.1 µg/cm2, respectively. We verified that this method was applicable to diversified materials including polymethyl methacrylate, polystyrene, thermoplastic polyurethane, polylactide acid, and poly(lactic-co-glycolic acid) and can be realized onto TCPS cell culture plates. This NIPS-based method is promising to generate porous surfaces on medical devices for incorporating therapeutic agents.


Subject(s)
Biomimetic Materials/chemistry , Polymers/chemistry , Animals , Cattle , Cells, Cultured , Humans , Materials Testing , Ofloxacin/chemistry , Particle Size , Porosity , Serum Albumin, Bovine/chemical synthesis , Surface Properties
4.
Ecotoxicology ; 30(8): 1652-1661, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33161467

ABSTRACT

During the urbanization, human activities have brought great changes to marine biodiversity and microbial communities of coastal water. Shenzhen is a coastal city that has developed rapidly over the past four decades, but the microbial communities and metabolic potential in offshore water are still not well characterized. Here, 16S rRNA gene V4-V5 sequencing was conducted to determine the microbial components from coastal waters in twenty selected areas of Shenzhen. The results showed a significant difference on the microbial composition between the western and eastern waters. Samples from western coast had more abundant Burkholderiaceae, Sporichthyaceae, Aeromonadaceae, and Methylophilaceae compared to eastern coast, and at the genus level, Candidatus Aquiluna, Aeromonas, Arcobacter, Ottowia and Acidibacter were significantly higher in western waters. There was also a notable difference within the western sample group, suggesting the taxa-compositional heterogeneity. Moreover, analysis of environmental factors and water quality revealed that salinity, pH and dissolved oxygen were relatively decreased in western samples, while total nitrogen, total phosphorus, chemical oxygen demand, and harmful marine vibrio were significantly increased compared to eastern waters. The results suggest the coastal waters pollution is more serious in western Shenzhen than eastern Shenzhen and the microbial communities are altered, which can be associated with anthropogenic disturbances.


Subject(s)
Microbiota , Biodiversity , Humans , RNA, Ribosomal, 16S/genetics , Salinity , Seawater , Water Quality
5.
ACS Appl Mater Interfaces ; 12(48): 54094-54103, 2020 Dec 02.
Article in English | MEDLINE | ID: mdl-33211468

ABSTRACT

Mussel-inspired poly(catecholamine) coatings from polydopamine (PDA) have been widely studied to design functional coatings for various materials. The chemical precursor of dopamine (DA), levodopa (l-DOPA, 3,4-dihydroxyphenyl-l-alanine), is known as the main element of mussel adhesive foot protein, but it is relatively hard to be constructed into a desirable coating on a given material surface under the same conditions as those for DA. Herein, we report a codeposition strategy to achieve the rapid fabrication of mussel-inspired coatings by l-DOPAwith polyethyleneimine (PEI) and to deeply understand the formation mechanism of those aggregates and coatings from l-DOPA/PEI. DFT calculations, fluorescence spectra, nuclear magnetic resonance analysis, and liquid chromatography-tandem mass spectrometry identification demonstrate that the formation of l-DOPA/PEI aggregates is effectively accelerated by PEI crosslinking with those intermediates of oxidized l-DOPA, including l-DOPAquinone and 5,6-dihydroxyindole-2-carboxylic acid as well as 5,6-dihydroxyindole, through Michael-addition and Schiff-base reactions. Therefore, we can facilely control the growth rate and the particle size of the l-DOPA/PEI aggregates in the deposition solution by adjusting the concentration of PEI. The coating formation rate of l-DOPA/PEI is four times faster than that of PDA and DA/PEI within 12 h. These l-DOPA/PEI coatings are demonstrated to display potential as structure colors, superhydrophilic surfaces, and antibacterial materials.

6.
World J Stem Cells ; 12(3): 222-240, 2020 Mar 26.
Article in English | MEDLINE | ID: mdl-32266053

ABSTRACT

BACKGROUND: Radiation induces rapid bone loss and enhances bone resorption and adipogenesis, leading to an increased risk of bone fracture. There is still a lack of effective preventive or therapeutic method for irradiation-induced bone injury. Receptor activator of nuclear factor κB ligand (RANKL) provides the crucial signal to induce osteoclast differentiation and plays an important role in bone resorption. However, the mechanisms of radiation-induced osteoporosis are not fully understood. AIM: To investigate the role of CR6-interacting factor-1 (Crif1) in osteoclastogenesis after radiation and its possible mechanism. METHODS: C57BL/6 mice were exposed to Co-60 gamma rays and received 5 Gy of whole-body sublethal irradiation at a rate of 0.69 Gy/min. For in vitro study, mouse bone marrow mesenchymal stem/stromal cells (BM-MSCs) were irradiated with Co-60 at a single dose of 9 Gy. For osteoclast induction, monocyte-macrophage RAW264.7 cells were cocultured with mouse BM-MSCs for 7 d. ClusPro and InterProSurf were used to investigate the interaction interface in Crif1 and protein kinase cyclic adenosine monophosphate (cAMP)-activited catalytic subunit alpha complex. Virtual screening using 462608 compounds from the Life Chemicals database around His120 of Crif1 was carried out using the program Autodock_vina. A tetrazolium salt (WST-8) assay was carried out to study the toxicity of compounds to different cells, including human BM-MSCs, mouse BM-MSCs, and Vero cells. RESULTS: Crif1 expression increased in bone marrow cells after radiation in mice. Overexpression of Crif1 in mouse BM-MSCs and radiation exposure could increase RANKL secretion and promote osteoclastogenesis in vitro. Deletion of Crif1 in BM-MSCs could reduce both adipogenesis and RANKL expression, resulting in the inhibition of osteoclastogenesis. Deletion of Crif1 in RAW264.7 cells did not affect the receptor activator of nuclear factor κB expression or osteoclast differentiation. Following treatment with protein kinase A (PKA) agonist (forskolin) and inhibitor (H-89) in mouse BM-MSCs, Crif1 induced RANKL secretion via the cAMP/PKA pathway. Moreover, we identified the Crif1-protein kinase cyclic adenosine monophosphate-activited catalytic subunit alpha interaction interface by in silico studies and shortlisted interface inhibitors through virtual screening on Crif1. Five compounds dramatically suppressed RANKL secretion and adipogenesis by inhibiting the cAMP/PKA pathway. CONCLUSION: Crif1 promotes RANKL expression via the cAMP/PKA pathway, which induces osteoclastogenesis by binding to receptor activator of nuclear factor κB on monocytes-macrophages in the mouse model. These results suggest a role for Crif1 in modulating osteoclastogenesis and provide insights into potential therapeutic strategies targeting the balance between osteogenesis and adipogenesis for radiation-induced bone injury.

7.
DNA Cell Biol ; 33(11): 793-801, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25068505

ABSTRACT

The aim of this study was to evaluate the associations between the rs3918396 G>A and rs528557 C>G polymorphisms in the disinterring and metalloproteinase domain 33 (ADAM33) gene and asthma risk. We searched CISCOM, CINAHL, Web of Science, PubMed, Google Scholar, EBSCO, Cochrane Library, and CBM databases from inception through August 1st, 2013 without language restrictions. Meta-analysis was performed using the STATA 12.0 software. Crude odds ratios (ORs) with their 95% confidence intervals (95% CI) were calculated. Thirteen case-control studies were included with a total of 7104 asthma patients and 8172 healthy controls. Our meta-analysis results revealed that ADAM33 rs528557 C>G polymorphism was associated with an increased risk of asthma (all p<0.05). However, we found no correlation between the ADAM33 rs3918396 G>A polymorphism and asthma risk (all p>0.05). Subgroup analysis by ethnicity indicated that the ADAM33 rs528557 C>G polymorphism might be strongly associated with an increased risk of asthma among both Caucasian and Asian populations (All p<0.05). No significant association was found between the ADAM33 rs3918396 G>A polymorphism and the risk of asthma among the studied ethnicities (All p>0.05). The present meta-analysis suggests that the ADAM33 rs528557 C>G polymorphism may contribute to susceptibility to asthma. Thus, the ADAM33 rs528557 C>G polymorphism may be utilized as a biomarker for early diagnosis of asthma.


Subject(s)
ADAM Proteins/genetics , Asthma/genetics , Asthma/ethnology , Genetic Predisposition to Disease , Humans , Risk Factors
8.
Tumour Biol ; 35(6): 5659-67, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24570186

ABSTRACT

Increasing scientific evidences suggest that aerobic exercise may improve cancer-related fatigue in breast cancer patients, but many existing studies have yielded inconclusive results. This meta-analysis aimed to derive a more precise estimation of the effects of aerobic exercise on cancer-related fatigue in breast cancer patients receiving chemotherapy. The PubMed, CISCOM, CINAHL, Web of Science, Google Scholar, EBSCO, Cochrane Library, and CBM databases were searched from inception through July 1, 2013 without language restrictions. Crude standardized mean difference (SMD) with 95 % confidence interval (CI) was calculated. Twelve comparative studies were assessed with a total of 1,014 breast cancer patients receiving chemotherapy, including 522 patients in the aerobic exercise group (intervention group) and 492 patients in the usual care group (control group). The meta-analysis results revealed that the Revised Piper Fatigue Scale (RPFS) scores of breast cancer patients in the intervention group were significantly lower than those in the control group (SMD=-0.82, 95% CI=-1.04 ∼ -0.60, P<0.001). However, there was no significant difference in the Functional Assessment of Chronic Illness Treatment-Fatigue scale (FACIT-F) scores between the intervention and control groups (SMD=0.09, 95% CI=-0.07 ∼ 0.25, P=0.224). Subgroup analysis by ethnicity indicated that there were significant differences in RPFS and FACIT-F scores between the intervention and control groups among Asian populations (RPFS: SMD=-1.08, 95% CI=-1.35 ∼ -0.82, P<0.001; FACIT-F: SMD=1.20, 95 % CI=0.70 ∼1.71, P<0.001), but not among Caucasian populations (all P>0.05). The current meta-analysis indicates that aerobic exercise may improve cancer-related fatigue in breast cancer patients receiving chemotherapy, especially among Asian populations.


Subject(s)
Antineoplastic Agents/adverse effects , Breast Neoplasms/drug therapy , Exercise , Fatigue/prevention & control , Asian People , Breast Neoplasms/complications , Breast Neoplasms/psychology , Case-Control Studies , Female , Humans , Publication Bias , Quality of Life
9.
Genes Chromosomes Cancer ; 53(5): 422-31, 2014 May.
Article in English | MEDLINE | ID: mdl-24532317

ABSTRACT

It has been previously demonstrated that genistein exhibits anticancer activity against breast cancer. However, the precise mechanisms underlying the anticancer effect of genistein, in particular the epigenetic basis, remain unclear. In this study, we investigated whether genistein could modulate the DNA methylation status and expression of cancer-related genes in breast cancer cells. We treated MCF-7 and MDA-MB-231 human breast cancer cells with genistein in vitro. We found that genistein decreased the levels of global DNA methylation, DNA methyltransferase (DNMT) activity and expression of DNMT1. Yet, the expression of DNMT3A and DNMT3B showed no significant change. Using molecular modeling, we observed that genistein might directly interact with the catalytic domain of DNMT1, thus competitively inhibiting the binding of hemimethylated DNA to the catalytic domain of DNMT1. Furthermore, genistein decreased DNA methylation in the promoter region of multiple tumor suppressor genes (TSGs) such as ataxia telangiectasia mutated (ATM), adenomatous polyposis coli (APC), phosphatase and tensin homolog (PTEN), mammary serpin peptidase inhibitor (SERPINB5), and increased the mRNA expression of these genes. However, we detected no significant changes in the DNA methylation status or mRNA expression of stratifin (SFN). These results suggest that the anticancer effect of genistein on breast cancer may be partly due to its ability to demethylate and reactivate methylation-silenced TSGs through direct interaction with the DNMT1 catalytic domain and inhibition of DNMT1 expression.


Subject(s)
Antineoplastic Agents/pharmacology , Breast Neoplasms/genetics , DNA Methylation/drug effects , Genes, Tumor Suppressor , Genistein/pharmacology , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Line, Tumor/drug effects , Cell Survival/drug effects , DNA (Cytosine-5-)-Methyltransferase 1 , DNA (Cytosine-5-)-Methyltransferases/genetics , DNA (Cytosine-5-)-Methyltransferases/metabolism , Epigenesis, Genetic , Female , Genome, Human , Humans , Models, Molecular
10.
Protein Pept Lett ; 19(4): 375-87, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22185507

ABSTRACT

Many proteins bear multi-locational characteristics, and this phenomenon is closely related to biological function. However, most of the existing methods can only deal with single-location proteins. Therefore, an automatic and reliable ensemble classifier for protein subcellular multi-localization is needed. We propose a new ensemble classifier combining the KNN (K-nearest neighbour) and SVM (support vector machine) algorithms to predict the subcellular localization of eukaryotic, Gram-negative bacterial and viral proteins based on the general form of Chou's pseudo amino acid composition, i.e., GO (gene ontology) annotations, dipeptide composition and AmPseAAC (Amphiphilic pseudo amino acid composition). This ensemble classifier was developed by fusing many basic individual classifiers through a voting system. The overall prediction accuracies obtained by the KNN-SVM ensemble classifier are 95.22, 93.47 and 80.72% for the eukaryotic, Gram-negative bacterial and viral proteins, respectively. Our prediction accuracies are significantly higher than those by previous methods and reveal that our strategy better predicts subcellular locations of multi-location proteins.


Subject(s)
Amino Acids/chemistry , Bacterial Proteins/classification , Databases, Protein , Viral Proteins/classification , Algorithms , Bacterial Proteins/chemistry , Cluster Analysis , Computational Biology , Dipeptides , Eukaryota , Oligopeptides/chemistry , Sequence Analysis, Protein , Support Vector Machine , Viral Proteins/chemistry
SELECTION OF CITATIONS
SEARCH DETAIL
...