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1.
Nanotechnology ; 35(29)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38593758

RESUMO

To break the resolution limitation of traditional resists, more work is needed on non-chemically amplified resists (non-CARs). Non-CARs based on iodonium salt modified polystyrene (PS-I) were prepared with controllable molecular weight and structure. The properties of the resist can be adjusted by the uploading of iodonium salts on the polymer chain, the materials with a higher proportion of iodonium salts show better lithography performance. By comparing contrast curves and quality of the lithographic patterns, the optimum developing condition of 4-methyl-2-pentanone and ethyl alcohol (v:v = 1:7) was selected. The high-resolution stripes of 15 nm half-pitch (HP) can be achieved by PS-I0.58in e-beam lithography (EBL). PS-I0.58shows the advanced lithography performance in the patterns of 16 nm HP and 18 nm HP stripes with low line edge roughness (3.0 nm and 2.4 nm). The resist shows excellent potential for further pattern transfer, the etch selectivity of resist PS-I0.58to the silicon was close to 12:1. The lithographic mechanism of PS-I was investigated by experimental and theoretical calculation, which indicates the polarity of materials changes results in the solubility switch. This work provides a new option and useful guidelines for the development of high-resolution resist.

2.
Biochem Genet ; 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37651071

RESUMO

The mitochondria are an important organelle in cells responsible for producing energy, and its abnormal function is closely related to the occurrence and development of osteoarthritis. Finding key genes associated with mitochondrial dysfunction in osteoarthritis can provide new ideas for the study of its pathogenesis. Firstly, 371 differential expressed genes (DEGs) were obtained through bioinformatics analysis of the GSE12021 and GSE55235 datasets in the GEO database, and 24 mitochondria-related DEGs (Mito-DEGs) were obtained by crossing differential genes with mitochondrial related genes. Next, KEGG and GO analysis of Mito-DEGs showed that upregulated Mito-DEGs were mainly enriched in small molecule catabolic process and tryptophan metabolism, while downregulated Mito-DEGs were mainly enriched in acetyl-CoA metabolic process and fatty acid biosynthesis. Furthermore, the key genes ME2 and MAOB were obtained through protein-protein interaction network analysis and lasso cox analysis of the 24 Mito-DEGs. In addition, the comparison results of immune cell scores showed differences between T cells CD4 memory resting, T cells regulatory (Tregs), Mast cells resting, and Mast cells activated in the OA group and the control group. More importantly, the potential regulatory mechanisms of key genes were studied through GSEA analysis and their correlation with immune infiltrating cells, immune checkpoints, m6A, and ferroptosis. Finally, in LPS-induced C28/I2 cells, silencing MAOB reduced inflammation injury and inhibited mitochondrial damage. Our research findings suggest that MAOB may hold potential as a target for the diagnosis and treatment of osteoarthritis.

3.
ACS Omega ; 8(30): 26739-26748, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37546582

RESUMO

2-Aminoanthracene was used as a nucleophilic additive in a molecular glass photoresist, bisphenol A derivative (BPA-6-epoxy), to improve advanced lithography performance. The effect of 2-aminoanthracene on BPA-6-epoxy was studied by electron beam lithography (EBL) and extreme ultraviolet lithography (EUVL). The result indicates that the additive can optimize the pattern outline by regulating epoxy cross-linking reaction, avoiding photoresist footing effectively in EBL. The EUVL result demonstrates that 2-aminoanthracene can significantly reduce line width roughness (LWR) for HP (Half-Pitch) 25 nm (from 4.9 to 3.8 nm) and HP 22 nm (from 6.9 to 3.0 nm). The power spectrum density (PSD) curve further confirms the reduction of roughness at medium and high frequency for HP 25 nm and the whole range of frequency for HP 22 nm, respectively. The study offers useful guidelines to improve the roughness of a chemically amplified molecular glass photoresist with epoxy groups for electron beam lithography and extreme ultraviolet lithography.

4.
Ann Microbiol ; 71(1)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34744534

RESUMO

PURPOSE: There has been an interest in the microbial azo dye degradation as an optional method for the treatment of azo dye-containing wastes. Tattoo ink is an extremely unique azo dye-rich environment, which have never been explored in terms of microorganisms capable of degrading azo dyes. Previously, we isolated 81 phylogenetically diverse bacteria, belonging to 18 genera and 52 species, contaminated in tattoo inks. In this study, we investigated if these bacteria, which can survive in the azo dye-rich environment, have an ability to degrade azo dyes. METHODS: We conducted a two-step azo dye degradation (or decolorization) assay. In step 1, a high-throughput degradability assay was done for 79 bacterial isolates using Methyl Red and Orange II. In step 2, a further degradation assay was done for 10 selected bacteria with a representative of 11 azo dyes, including 3 commercial tattoo ink azo dyes. Degradation of azo dyes were calculated from measuring optical absorbance of soluble dyes at specific wavelengths. RESULTS: The initial high-throughput azo dye assay (step 1) showed that 79 isolates had a complete or partial degradation of azo dyes; > 90% of Methyl Red and Orange II were degraded within 24 h, by 74 and 20 isolates, respectively. A further evaluation of azo dye degradability for 10 selected isolates in step 2 showed that the isolates, belonging to Bacillus, Brevibacillus, Paenibacillus, and Pseudomonas, exhibited an excellent decolorization ability for a wide range of azo dyes. CONCLUSIONS: This study showed that phylogenetically diverse bacteria, isolated from azo dye-rich tattoo inks, is able to degrade a diverse range of azo dyes, including 3 azo dyes used in commercial tattoo inks. Some of the strains would be good candidates for future studies to provide a systematic understanding of azo dye degradation mechanisms.

5.
Foodborne Pathog Dis ; 18(8): 616-625, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34403269

RESUMO

While Shiga toxin-producing Escherichia coli (STEC) is a major foodborne pathogen worldwide, data on the molecular and phylogenetic properties of STEC isolates from retail beef samples in China remain scant. Fresh retail beef samples (n = 1062) were collected from eight provinces, and STEC isolates were recovered and characterized. PCR data showed that more than 50% of the samples were stx positive, and 82 STEC isolates were recovered from 14.8% (79/535) stx-positive enriched broths. In contrast, all ciprofloxacin resistant isolates (n = 19) and 13 cefotaxime (CTX) resistant isolates were eae positive and belonged to three serotypes: O111:H8, O26:H11, or O157:H7. Point mutations in quinolone resistance-determining regions and plasmid-mediated quinolone resistance determinants were identified in 16 and 20 isolates, respectively. BlaCTX-M and a point mutation (C-42T) in ampC promoter were detected in 15 and 8 of the CTX resistant isolates, respectively. In addition, macrolide resistance gene mphA was identified in eight azithromycin resistant O111:H8 isolates and one O26:H11 isolate. Single nucleotide polymorphism analysis demonstrated that the O26 and O157 isolates had multiple origins, but the O111 isolates were closely related. Taken together, our data demonstrated that several sequence types associated with hemolytic uremic syndrome from the retail beef samples in China had developed into dangerous multidrug resistant pathogens. The resistant phenotype can facilitate their transmission among the farm animals and human beings when there is an antimicrobial selective pressure.


Assuntos
Proteínas de Escherichia coli/isolamento & purificação , Microbiologia de Alimentos/estatística & dados numéricos , Carne Vermelha/microbiologia , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/isolamento & purificação , Animais , China , Resistência a Múltiplos Medicamentos/genética , Humanos , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Sorogrupo , Fatores de Virulência/genética
6.
Food Res Int ; 143: 110294, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33992393

RESUMO

Complex microbiomes of pit mud (PM) play significant roles in imbuing flavors and qualities of Chinese strong-flavor liquor (CSFL) during fermentation. However, understanding both of the taxonomic and functional diversity of the whole microorganisms in PM still remain a major challenge. Here, PM microbiomes were investigated based on metagenomic sequencing, assembly and binning. Metagenomic data revealed that Euryarchaeota was the predominant phylum, followed by Firmicutes, Proteobacteria, Bacteroidetes and Actinobacteria. For further functional exploration, 703 metagenome-assembled genomes (MAGs), including 304 novel strains, 197 novel species, and 94 novel genera were reconstructed. Three primary groups of Firmicutes (n = 406), Euryarchaeota (n = 130) and Bacteroidetes (n = 74), particularly genus of them Syntrophomonas, Thermacetogenium and Clostridium, methanogens (Methanobacterium, Methanoculleus, and Methanosarcina), Proteiniphilum and Prevotella, contained most of metabolic potential genes. Additionally, Chloroflexi was firstly reported to have potential to be involved in the caproic acid (CA) production. Bacteroidetes could be the key phylum to synthesize terpenes, and Armatimonadetes, Firmicutes, Ignavibacteriae and Verrucomicrobia may possess the same metabolic potential as well. Overall, this study will significantly improve our understanding of the diverse PM microbiome and help guide the future exploration of microbial resources for modifying PM fermentation processes.


Assuntos
Metagenoma , Microbiota , Bactérias/genética , China , Fermentação
7.
Front Microbiol ; 12: 771361, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35095791

RESUMO

Alfalfa (Medicago sativa L.) is one of the most widely cultivated forage crops in the world. China is the second largest producer of alfalfa in terms of the planting area worldwide, with Gansu, Henan, Inner Mongolia, and Shaanxi provinces being the production hubs. Alfalfa viruses have been reported on a small-scale survey in some of these areas, but they have not been well characterized. In the present study, seven viruses were detected in 12 fields of 10 cities/counties of the four abovementioned provinces by high-throughput sequencing and assembly of small RNA. Their incidence, distribution, and genetic diversity were analyzed by enzyme-linked immunosorbent assay, polymerase chain reaction (PCR)/reverse transcription-PCR and clone sequencing. The results showed that alfalfa mosaic virus (AMV), pea streak virus (PeSV), lucerne transient streak virus (LTSV), alfalfa dwarf virus (ADV), Medicago sativa alphapartitivirus 1 (MsAPV1), MsAPV2, and alfalfa leaf curl virus (ALCV) were the main viruses infecting alfalfa in four examined provinces. AMV and MsAPV1 had the highest incidences in all 4 provinces. SDT analysis of the 7 viruses isolated in China revealed a highly conserved among AMV, LTSV, ADV, MsAPV1, MsAPV2, and ALCV, but the sequence was a high variation between China isolates to abroad isolates in PeSV, ADV, and ALCV. To our knowledge, this is the first report of ADV in Inner Mongolia and Gansu, ALCV in Inner Mongolia, MsAPV1 and MsAPV2 in all 4 provinces, and PeSV and LTSV in China. These findings provide a basis for future research on the genetic evolution of alfalfa viruses in China and on strategies to prevent diseases in alfalfa caused by these viruses.

8.
PLoS One ; 14(5): e0210453, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31063499

RESUMO

Germination of seeds during the transportation or after prolonged storage naturally and inevitably decreases because of ageing, but germination potential can be partially restored with seed priming treatments. A novel attempt was made to investigate the effects of combined treatments and to optimize the conditions for naturally aged seeds of tall fescue (Festuca arundinacea Schreb.), orchardgrass (Dactylis glomerata L.) and Russian wild rye (Psathyrostachys juncea (Fisch.) Nevski) using an orthogonal activity level experimental design [factor A: Azospirillum brasilense concentration, factor B: three seed priming treatments (H2O, MgSO4 and H2O2) and factor C: different priming times]. Multivariate regression model analysis was applied to determine the interactive effects of pairwise factors (A and C) and to optimize experimental conditions. The results showed that the mixed treatments positively affected seed germination and seedling growth. The three seed priming treatments were the dominant factors for germination promotion, whereas the bacterial concentration had the largest effect on seedling growth and the activity of superoxide dismutase (SOD), especially root elongation. The malondialdehyde content was reduced, the activities of SOD, peroxidase and catalase were triggered, and ascorbate peroxidase activity was also affected by the co-treatment. The combined results of all determined attributes showed that A. brasilense bio-priming with H2O2 priming constituted the optimal combination. The optimal bacterial concentration of A. brasilense and the time of seed priming were 52.3 × 106 colony forming units (CFU) mL-1 and 17.0 h, respectively.


Assuntos
Azospirillum brasilense/fisiologia , Germinação/fisiologia , Poaceae/fisiologia , Plântula/fisiologia , Sementes/fisiologia , Simbiose , Biomarcadores
9.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 31(12): 1447-1451, 2017 12 15.
Artigo em Chinês | MEDLINE | ID: mdl-29806385

RESUMO

Objective: To introduce a modified technique for treating acute closed Achilles tendon rupture and evaluate the preliminary effectiveness. Methods: Between March 2011 and September 2015, 8 cases (8 sides) with acute closed Achilles tendon rupture were repaired with the laminated bevel suturing technique. All of the patients were male with an average age of 39.3 years (range, 22-58 years), injured in nonprofessional sports. The diagnosis was confirmed by typical signs of positive heel-lift test and Thompson test; the complete rupture of Achilles tendon was determined by color Doppler ultrasound or MRI, and the distance between the stump and calcaneus was 2-5 cm (mean, 3.3 cm). The time from injury to operation was 2-12 days (mean, 4.1 days). With the patient in prone position, a posterior longitudinal incision medial to the tendon was made, the broken stumps of Achilles tendon were divided into 3 layers on the coronal plane, fibers made into strips. The strips were staggered and stacked, stitched side to side with absorbable suture. The ankle joint at the plantar flexion position was fixed with plaster, and early rehabilitation exercise was carried out. Results: The operation time was 70-135 minutes (mean, 99 minutes); the intraoperative blood loss was 5-30 mL (mean, 15.6 mL). All the incisions healed by first intention without infection, except for 1 case who need dressing exchange because of partial delayed healing. All the patients were followed up 6-50 months (mean, 30.5 months). There was no complication of surgical site infection, sural nerve injury, or deep vein thrombosis. The patients could walk normally with powerful raising heels and return to previous sports, without complication of re-rupture. Compared with the contralateral side, the activity of ankle joint dorsiflexion reduced 0-6° (mean, 3°); plantar flexion reduced 1-5° (mean, 2°). At last follow-up, according to Arner-Lindholm score, the surgical results were excellent in 7 cases and good in 1 case, with an excellent and good rate of 100%. Conclusion: Laminated bevel suturing technique is simple for repairing acute closed Achilles tendon rupture without the need of special surgical instruments. It provides enough tensile strength for early rehabilitation exercise to rapid and good recovery.


Assuntos
Tendão do Calcâneo/lesões , Técnicas de Sutura , Traumatismos dos Tendões/cirurgia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Ruptura , Suturas , Resultado do Tratamento , Adulto Jovem
10.
Exp Ther Med ; 9(5): 1589-1592, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26136863

RESUMO

Contaminating bacteria are only found on wound surfaces in the initial stages of open fractures; therefore, effective debridement is critical for bacterial infection prevention and the reduction of inflammatory reactions. Various irrigation solutions are currently being used; however, a comprehensive study on their efficacy is lacking. In the present study, a comparison of the effects of normal saline, iodophor and hydrogen peroxide as the irrigation solutions for debridement of open femur fractures in rat models was conducted. It was revealed that all three solutions were comparably effective in bacterial removal while normal saline was superior in minimizing adverse wound inflammation; therefore, the use of normal saline for routine debridement is recommended in the early-stage treatment of open fractures in the trauma clinic and in relief fieldwork.

11.
J Nanosci Nanotechnol ; 14(4): 2810-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24734694

RESUMO

The cationic PLL-Fe2o3/SiO2-siRNA nanoparticles with an average crystallite size of about 20 nm were prepared and delivered into primary rat neurons for knockdown of gene expression. Primary rat fetal neurons were scratched to simulate the injury of central nervous system and then were transfected with PLL-Fe2O3/SiO2-siRNA nanoparticles. Optical microscopy, fluorescence microscopy, Western blotting, immunofluorescence, and MTT assays were employed to test the cytotoxicity, the efficiency of encapsulation and targeted gene silencing. The results indicated that the PLL-Fe2O3/SiO2-siRNA nanoparticles have a remarkable efficiency of encapsulation and targeted gene silencing with negligible cytotoxicity. It could be concluded that the PLL-Fe2O3/SiO2 nanoparticles are a promising delivery carrier of siRNA.


Assuntos
Compostos Férricos/química , Inativação Gênica , Nanopartículas/química , Neurônios/metabolismo , Polilisina/química , RNA Interferente Pequeno/metabolismo , Dióxido de Silício/química , Animais , Western Blotting , Cátions , Morte Celular , Permeabilidade da Membrana Celular , Proliferação de Células , Células Cultivadas , Feminino , Imunofluorescência , Neurônios/citologia , Ratos , Ratos Sprague-Dawley , Difração de Raios X
12.
J Nanosci Nanotechnol ; 14(3): 2670-3, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24745283

RESUMO

The alpha-Fe2O3 nanotubes with diameters of 400-700 nm were prepared by calcination of electrospun precursors. The morphology of alpha-Fe2O3 nanotubes is mainly influenced by the water content in solution and heating rate during the calcination process. When the water content is about 17 wt.%, heating rate is 5 degrees C/min and calcination temperature at 500 degrees C for 2 h, the optimized alpha-Fe2O3 nanotubes are obtained. These alpha-Fe2O3 nanotubes have a magnetization (M(s)) of 0.36 emu x (9-1) and coercivity (H(o)) of 1942 Oe and can be used in the nanospace technology.

13.
J Nanosci Nanotechnol ; 13(4): 2835-41, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23763168

RESUMO

Magnetic Ni0.5Zn0.5Fe2O4 nanoparticles were synthesized by the facile citrate-gel process. Their morphology, chemical composition, microstructure, and magnetic properties were investigated by XRD, TEM, EDX, BET, and VSM. The as-prepared magnetic Ni0.5Zn0.5Fe2O4 nanoparticles consisting of grains about 20 nm were characterized with specific surface area of 49.0 m2/g and magnetization of 46.1 A m2/kg. The arsenic(V) adsorption onto these magnetic Ni0.5Zn0.5Fe2O4 nanoparticles at room temperature was determined by the ICP-AES measurement of arsenic(V) in aqueous solution. The results show that the pseudo-second-order kinetic model is fitted well to describe the arsenic(V) adsorption process with a determination coefficient (R2 = 0.9862). By comparing with the two- and three-parameter models for adsorption isotherms of arsenic(V) onto the magnetic Ni0.5Zn0.5Fe2O4 nanoparticles at room temperature, the Temkin and Redlich-Peterson model can be used to evaluate the arsenic(V) adsorption isotherm at room temperature. The arsenic(V) equilibrium adsorption quantity is up to 7.2 mg/g for these magnetic Ni0.5Zn0.5Fe2O4 nanoparticles when the initial arsenic(V) concentration is 3 mg/L in aqueous solution.


Assuntos
Arsênio/química , Nanopartículas Metálicas , Termodinâmica , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Magnetismo , Microscopia Eletrônica de Transmissão , Soluções , Temperatura , Água
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