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1.
ESC Heart Fail ; 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34612024

RESUMO

Myocardial fibrosis detected by cardiac magnetic resonance (CMR) has been reported in patients with desmin-related myopathy, although its characteristics remain unclear. Here, we describe a case of desmin-related restrictive cardiomyopathy wherein CMR imaging revealed myocardial oedema, ischaemia, and fibrosis in the left ventricle; the different types and processes of myocardial injury were detected by CMR. Middle wall left ventricular enhancement may be a feature of late gadolinium enhancement, and the lateral wall is often involved in cases of myocardial injury. CMR is useful for the early detection of cardiac involvement and the prediction of prognosis in patients diagnosed with desmin-related myopathy.

2.
J Cutan Pathol ; 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34622970

RESUMO

Primary cutaneous anaplastic large cell lymphoma (pC-ALCL) is distinguished from systemic anaplastic large cell lymphoma (S-ALCL) with cutaneous involvement. Although pC-ALCL is a unique entity with different genetics, clinical characteristics, and prognosis, its causes are unknown. Herein, we report the case of a Chinese woman with a 4-month history of a gradually enlarged ulcerative mass in her right forearm following an unidentified insect bite. Biopsy revealed an extensive infiltrate with patches of large anaplastic lymphoid cells. These cells were immunohistochemically positive for CD45, CD30, and TIA-1 and negative for CD2, CD3, CD4, CD5, CD20, CD7, CD8, and ALK-1. DUSP22-IRF4 rearrangement was detected whereas TP63 rearrangement was not observed by fluorescence in situ hybridization (FISH). No Epstein-Barr virus-encoded small RNAs (EBERs) were detected by ISH. Rearrangement of monoclonal TCR gene was found using BIOMED-2 polymerase chain reaction. No abnormality was found on the subsequent positron emission tomography-computed tomography (PET-CT) scan. After five cycles of CHOP chemotherapy, the patient achieved complete remission. This is the first report of a unique pC-ALCL with DUSP22-IRF4 rearrangement following an insect bite other than S-ALCL involving the skin. This article is protected by copyright. All rights reserved.

3.
Clin Exp Hypertens ; : 1-6, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34633263

RESUMO

BACKGROUND: To analyze the association between triglyceride-glucose index (TYG index) and hyperuricemia (HUA) in elderly patients with hypertension. METHODS: A total of 428 inpatients with primary hypertension from March 2018 to March 2021 in Qinghai Provincial People's Hospital were retrospectively analyzed. Grouped by sex and serum uric acid. Serum uric acid (SUA), fasting blood glucose (FPG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), serum creatinine (Scr), urea nitrogen (BUN), triglycerides (TG), high-sensitivity C-reactive protein (HS-CRP) and other biochemical indicators were measured, and the TYG index was calculated. The TYG index and SUA levels of each group were compared, and the correlation between TYG index and hyperuricemia was analyzed. Multivariate Logistic regression was performed to analyze the relationship between TYG index and the risk of HUA in elderly patients with hypertension. The ROC curve was used to evaluate the predictive value of TYG index in elderly patients with hypertension associated with HUA. RESULTS: TYG index was significantly higher in the HUA group than in the normal group in both men and women (P < .05). Spearson correlation analysis showed that TYG index positively correlated with TC, TG, FPG, SUA, and LDL-C(r = 0.327, 0.975, 0.412, 0.214, 0.215, P = .000, 0.000, 0.000, 0.000, 0.000), and negatively correlated with age and HDL-C (r = -0.166, -0.248, P = .001, 0.000). Logistic regression analysis showed that Scr, BUN, HS-CRP and TYG index were the risk factors for HUA in elderly patients with hypertension (P < .05).The ROC curve showed an area under the TYG exponential curve of 0.617(95%CI:0.561 ~ 0.673) with a sensitivity of 64.4% and a specificity of 57.4%. CONCLUSION: TYG index in elderly hypertensive patients is closely related to hyperuricemia, and the increase of TYG index is an independent risk factor for HUA in elderly hypertensive patients.

4.
Artigo em Inglês | MEDLINE | ID: mdl-34639832

RESUMO

The COVID-19 has caused a serious impact on the global economy, and all countries are in a predicament of fighting the epidemic and recovering their economies. Aiming to discuss the impact of the COVID-19 on the economic resilience of urban agglomerations, the economic data of each quarter from June 2019 to September 2020 of the Beijing-Tianjin-Hebei Urban Agglomeration are selected, and the economic development index (EDI) is calculated based on the entropy method. Combining the fundamental conditions of urban agglomerations and industrial policies during the COVID-19, urban economic resilience is discussed by the changing trend of the economic development index (EDI) and dividing into resistance and restoration. The results show that: (1) The economic development level of the urban agglomeration has been affected by the epidemic and has changed significantly. The change of endogenous power is the main cause of change; (2) During the outbreak of the COVID-19, the economic resilience of the Beijing-Tianjin-Hebei urban agglomeration shows four different development types: high resistance and restoration, high resistance but low restoration, low resistance but high restoration, low resistance and restoration cities; (3) High resistance but low restoration, low resistance but high restoration, and low resistance and restoration cities influence each other, but the relationship between cities is mainly dependent; (4) The economic restoration within the urban agglomeration forms a synergy, which promotes the economic recovery and development of the urban agglomeration during the recovery period of the COVID-19. Urban agglomerations should enhance the combined effect of resistance and increase the impact of high resistance and restoration cities on surrounding cities in the future.

5.
Talanta ; 235: 122803, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517661

RESUMO

An electrochemical biosensor for highly sensitive detection of tobacco mosaic virus (TMV) RNA (tRNA) based on click chemistry and photoinduced atom transfer radical polymerization (photoATRP) is developed for the first time. Herein, tRNA is recognized and captured by hairpin DNA immobilized on the gold electrode surface by Au-S self-assembly. Propyl 2-bromoisobutyrate (PBIB), a photoATRP initiator containing an alkyne group, is conjugated to the azide group of hairpin DNA via a Cu(I)-catalyzed azidoalkyl cyclization reaction (CuAAC). Under the irradiation of 470 nm blue light, photoATRP is activated by the photoredox catalyst (eosin Y, EY), resulting in the formation of a large number of electroactive probes (ferrocenylmethyl methacrylate, FMMA), which significantly amplifies the signal. Under the optimal experimental parameters, the strategy has a wide linear detection (0.1 pM-10 nM) (R2 = 0.995) with a limit of detection (LOD) as low as 3.5 fM. In addition, the biosensor also exhibited good selectivity for mismatched bases, excellent stability and reproducibility. Moreover, satisfactory result was achieved when the biosensor was applied to the detection of tRNA from healthy rehmannia total RNA extracts, which demonstrates the great potential of the method in the practical detection of TMV.


Assuntos
Técnicas Biossensoriais , Vírus do Mosaico do Tabaco , Química Click , Técnicas Eletroquímicas , Limite de Detecção , Polimerização , RNA , Reprodutibilidade dos Testes
6.
Mamm Genome ; 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34498136

RESUMO

Although DNA array-based approaches for genome-wide association studies (GWAS) permit the collection of thousands of low-cost genotypes, it is often at the expense of resolution and completeness, as SNP chip technologies are ultimately limited by SNPs chosen during array development. An alternative low-cost approach is low-pass whole genome sequencing (WGS) followed by imputation. Rather than relying on high levels of genotype confidence at a set of select loci, low-pass WGS and imputation rely on the combined information from millions of randomly sampled low-confidence genotypes. To investigate low-pass WGS and imputation in the dog, we assessed accuracy and performance by downsampling 97 high-coverage (> 15×) WGS datasets from 51 different breeds to approximately 1× coverage, simulating low-pass WGS. Using a reference panel of 676 dogs from 91 breeds, genotypes were imputed from the downsampled data and compared to a truth set of genotypes generated from high-coverage WGS. Using our truth set, we optimized a variant quality filtering strategy that retained approximately 80% of 14 M imputed sites and lowered the imputation error rate from 3.0% to 1.5%. Seven million sites remained with a MAF > 5% and an average imputation quality score of 0.95. Finally, we simulated the impact of imputation errors on outcomes for case-control GWAS, where small effect sizes were most impacted and medium-to-large effect sizes were minorly impacted. These analyses provide best practice guidelines for study design and data post-processing of low-pass WGS-imputed genotypes in dogs.

7.
J Hazard Mater ; 416: 125721, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492775

RESUMO

Chlorophenols (CPs) are toxic contaminants that tend to accumulate in textile dyeing sludge and pose a threat to the environment through the disposal process. To comprehensively evaluate CPs in sludge, the characteristics and risks of CPs from five textile dyeing plants (TDPs) were investigated in this study. The total concentration of 19 CPs (Σ19 CPs) varied from 170.90 to 6290.30 ng g-1 dry weight (dw), among which high-chlorine phenols accounted for the greatest proportion. The ecological screening level (ESL) of CPs was used to judge their pollution levels, while the risk quotient (RQ) value and dioxin conversion rate were used to analyze their potential risk. The results indicated that CPs may pose a moderate to high risk to the environment. The Fenton process was used to condition the hazardous sludge, and a higher content of CPs was found after conditioning. A lower rate of CP increase was achieved with a reagent dose of 180 mmol/L, H2O2:Fe2+ = 1:1, pH of 3-4 and reaction time of 30 min. In summary, the work helps to address the general knowledge gap in the textile dyeing industry and provides a reference for further research.


Assuntos
Clorofenóis , Esgotos , Peróxido de Hidrogênio , Indústria Têxtil , Têxteis
8.
Environ Sci Technol ; 55(19): 13186-13197, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34521194

RESUMO

The performance of fresh (PdV/TiO2), sulfur poisoned (Used-S and Used-H), and regenerated (Used-RS and Used-RH) multi-active center catalysts for chlorobenzene catalytic oxidation and selective catalytic reduction (CBCO + SCR) reaction is investigated. The reaction on the catalyst surface is blocked after sulfur poisoning owing to the occupation and deposition of catalyst active centers (mainly Pd centers) by PdSO4 (and/or PdS in a dry environment) and NH4HSO4 species, especially the CBCO process. Sulfates (mainly NH4HSO4) on the sulfur poisoned catalyst surface are partially decomposed after 400 °C thermal regeneration, while the deactivation caused by the formation of PdSO4 species is irreversible. Density functional theory calculation results show that in the PdSO4 and NH4HSO4 generation paths, each step of the elementary reaction has just a small energy barrier to overcome, and the stability of the product for each elementary reaction increases gradually. Even worse, SO2 is easily combined with H2O gas molecules to form H2SO3 in a humid environment, and the energy barrier for conversion of SO32- to SO42- is just 0.041 eV. The two oxygen vacancies (VOx-1 or TiOx-1) provide adsorption sites for CBCO + SCR reaction gas molecules but do not exhibit adsorption properties for SO2, which gives a possible idea for optimization of sulfur resistance. The present work is favorable for further synergistic removal of CB/NOx by the catalyst for anti-SO2 poisoning modification and application in the manufacture industry.

9.
Cancer Biol Ther ; : 1-7, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34570671

RESUMO

Follicular lymphoma (FL) accounts for approximately 35% of all non-Hodgkin lymphomas and can progress to diffuse large B cell lymphoma (DLBCL) at a rate of 2% per year. Here, we present a 56-year-old female patient who was diagnosed with grade 3a FL. Further pathological investigation revealed that the lymphoma had transformed into DLBCL following six courses of R-CHOP regimen, and further disease progression was observed after two courses of R2-GemOx. We ultimately failed to collect hematopoietic stem cells after two courses of R2-ICE. CD-22 CAR-T cell therapy salvaged the patient; however, a new soft tissue mass of 4.8 × 4.1 cm rapidly emerged in the patient's right lung. Following the observation of strong tissue staining of PD-L1 (90%), the patient was administered PD-1 inhibitor and 26 Gy of radiotherapy and has maintained progression-free survival at more than 15 months of follow-up. Transformed FL with strong PD-L1 expression showed a poor response to standard immunochemotherapy. Our findings support the potential benefit of PD-1 inhibitor and combination therapies in this type of transformed FL.

10.
J Environ Manage ; 299: 113636, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34467862

RESUMO

BiOBr is a kind of promising photocatalyst because of excellent photoelectric separation efficiency and chemical stability. In order to improving practical application performance, a novel BiOBr ultra-thin nano-roundel (BiOBr-nR) was constructed in water-in-oil (WIO) emulsion microspheres, and prepared by hydrothermal reaction. Its specific surface area was increased by changing microtopography and downsizing. After being characterized by FT-IR, X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), scanning electron microscope (SEM), Brunauer-Emmett-Teller (BET), UV-Vis diffuse reflectance spectra (UV-Vis DRS) and photoluminescence (PL), it indicated the BiOBr-nR, being doped by C and N, is 4-5 times smaller and thinner than that of conventional BiOBr. It was also found that BiOBr-nR has narrower band gap energy (2.78 eV), excellent photocatalytic activity, significant reusability, and stability. The obtained BiOBr-nR photocatalysts were applied to remove organics. It presented excellent photocatalytic activity, the degradation rate of organics got to 99.2%. The mechanism of photodegradation was investigated, which indicated superoxide radicals and holes play a major role in the degradation of organics. Therefore, BiOBr-nR is a kind of environmentally friendly photocatalyst with stable photocatalytic activity, the removal rate still more than 97% after recycling for 10 times. In summary, we found a novel insight for designing and preparation of efficient and recyclable BiOBr photocatalytic materials, which exhibits high photoresponse for purifying the wastewater.


Assuntos
Bismuto , Catálise , Fotólise , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Database (Oxford) ; 20212021 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-34389843

RESUMO

Protein-nucleic acid complexes play essential roles in regulating transcription, translation, DNA replication, repair and recombination, RNA processing and translocation. Site-directed mutagenesis has been extremely useful in understanding the principles of protein-DNA and protein-RNA interactions, and experimentally determined mutagenesis data are prerequisites for designing effective algorithms for predicting the binding affinity change upon mutation. However, a vital challenge in this area is the lack of sufficient public experimentally recognized mutation data, which leads to difficulties in developing computational prediction methods. In this article, we present Nabe, an integrated database of amino acid mutations and their effects on the binding free energy in protein-DNA and protein-RNA interactions for which binding affinities have been experimentally determined. Compared with existing databases and data sets, Nabe is the largest protein-nucleic acid mutation database, containing 2506 mutations in 473 protein-DNA and protein-RNA complexes, and of that 1751 are alanine mutations in 405 protein-nucleic acid complexes. For researchers to conveniently utilize the data, Nabe assembles protein-DNA and protein-RNA benchmark databases by adopting the data-processing procedures in the majority of models. To further facilitate users to query data, Nabe provides a searchable and graphical web page. Database URL: http://nabe.denglab.org.

13.
Neoplasma ; 68(5): 1033-1042, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34427098

RESUMO

It has been reported that cyclin-dependent kinase like 3 (CDKL3) plays a crucial role in cell proliferation and migration in several cancers. However, the function of CDKL3 in triple-negative breast cancer (TNBC) is still unclear. In the present study, immunohistochemistry (IHC) was conducted to detect the CDKL3 expression. CCK-8, flow cytometry, Transwell assays, and mice xenograft models, were performed to explore the roles of CDKL3 on the proliferation and migration of TNBC in vitro and in vivo. Besides, protein chip analysis was used to screen the potential pathways, which was further confirmed by promoter activity assay, western blotting, and CCK-8 assay. Our findings reveal a high expression of CDKL3 in TNBC tissues, which is closely related to a poor prognosis of patients with TNBC. In TNBC cells, CDKL3 knockdown inhibits cell proliferation and migration, whereas CDKL3 overexpression has exactly the opposite effect. Consistently, CDKL3 knockdown induces cell apoptosis in vitro but suppresses tumor growth in vivo. Furthermore, CDKL3 knockdown increases p53 expression and reduces cell viability, and these effects are significantly weakened by the p53 inhibitor, PFT-α. In conclusion, the current study highlights that CDKL3 promotes TNBC progressions via regulating the p53 signaling pathway, suggesting that CDKL3 is a novel therapeutic target for TNBC treatment.


Assuntos
Proteínas Serina-Treonina Quinases/metabolismo , Neoplasias de Mama Triplo Negativas , Animais , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais , Neoplasias de Mama Triplo Negativas/genética , Proteína Supressora de Tumor p53/genética
14.
Curr Med Imaging ; 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34365951

RESUMO

BACKGROUND: Artificial intelligence (AI)-based automatic lung nodule detection system improves the detection rate of nodules. It is important to evaluate the clinical value of AI system by comparing AI-assisted nodule detection with actu-al radiology reports. OBJECTIVE: To compare the detection rate of lung nodules between the actual radiology reports and AI-assisted reading in lung cancer CT screening. METHODS: Participants in chest CT screening from November to December 2019 were retrospectively included. In the real-world radiologist observation, 14 residents and 15 radiologists participated to finalize radiology reports. In AI-assisted reading, one resident and one radiologist reevaluated all subjects with the assistance of an AI system to lo-cate and measure the detected lung nodules. A reading panel determined the type and number of detected lung nodules between these two methods. RESULTS: In 860 participants (57±7 years), the reading panel confirmed 250 patients with >1 solid nodule, while radiolo-gists observed 131, lower than 247 by AI-assisted reading (p<0.001). The panel confirmed 111 patients with >1 non-solid nodule, whereas radiologist observation identified 28, lower than 110 by AI-assisted reading (p<0.001). The accuracy and sensitivity of radiologist observation for solid nodules were 86.2% and 52.4%, lower than 99.1% and 98.8% by AI-assisted reading, respectively. These metrics were 90.4% and 25.2% for non-solid nodules, lower than 98.8% and 99.1% by AI-assisted reading, respectively. CONCLUSION: Comparing with the actual radiology reports, AI-assisted reading greatly improves the accuracy and sensi-tivity of nodule detection in chest CT, which benefits lung nodule detection, especially for non-solid nodules.

16.
Mol Biol Evol ; 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34289055

RESUMO

Coexistence and cooperation between dogs and humans over thousands of years have supported convergent evolutionary processes in the two species. Previous studies found that Eurasian dogs evolved into a distinct geographic cluster. In this study, we used the genomes of 242 European dogs, 38 Southeast Asian indigenous dogs (SEAI) and 41 grey wolves to identify adaptation of European dogs. We report 86 unique positively selected genes (PSGs) in European dogs, among which is LCT (lactase). LCT encodes lactase which is fundamental for the digestion of lactose. We found that an A-to-G mutation (chr19:38,609,592) is almost fixed in Middle Eastern and European dogs. The results of 2 D SFS support that the mutation is under soft sweep. We inferred that the onset of positive selection of the mutation is shorter than 6,535 years and behind the well-developed dairy economy in central Europe. It increases the expression of LCT by reducing its binding with ZEB1, which would enhance dog's ability to digest milk-based diets. Our study uncovers the genetic basis of convergent evolution between humans and dogs with respect to diet, emphasizing the import of the dog as a bio-medical model for studying mechanisms of the digestive system.

17.
Artigo em Inglês | MEDLINE | ID: mdl-34292452

RESUMO

In recent decades, antibiotics and antibiotic resistance genes (ARGs) have been regarded as emerging pollutants. In Taihu Lake, as a typical representative of freshwater system in China, the ARGs occurrence and abundance was of great importance for ecological risk control and public health protection. In this research, high-throughput sequencing and metagenomics technique were used to investigate the seasonal ARGs profile in overlying water and sediment at typical area of Taihu Lake. Besides, taxonomy pattern of ARGs host bacteria and potential pathogens were identified. The results showed that 33 ARG subtypes and 11 ARG types were detected in research area, among which bacitracin, multidrug and sulfonamides resistance gene were with the highest abundance. The relative abundance of ARGs in overlying water and sediment ranged from 1.68 to 661.05 ppm and from 1.93 to 49.47 ppm, respectively. ARG host (18 bacteria genus) were identified and annotated, among which Clostridium botulinum, Pseudomonas aeruginosa and Klebsiella pneumonia were pathogenic bacteria. The pathogens were mostly detected at Xukou Bay in spring and fall, which might be caused by the inlet water from aquaculture area of Yangcheng Lake. Pseudomonas was the most abundant ARGs host (ant2ib, baca, bl2d_oxa2,mexb, mexf, mexw and oprn), which may facilitate the propagation of ARGs in freshwater system.

18.
BMC Biol ; 19(1): 118, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34130700

RESUMO

BACKGROUND: Species domestication is generally characterized by the exploitation of high-impact mutations through processes that involve complex shifting demographics of domesticated species. These include not only inbreeding and artificial selection that may lead to the emergence of evolutionary bottlenecks, but also post-divergence gene flow and introgression. Although domestication potentially affects the occurrence of both desired and undesired mutations, the way wild relatives of domesticated species evolve and how expensive the genetic cost underlying domestication is remain poorly understood. Here, we investigated the demographic history and genetic load of chicken domestication. RESULTS: We analyzed a dataset comprising over 800 whole genomes from both indigenous chickens and wild jungle fowls. We show that despite having a higher genetic diversity than their wild counterparts (average π, 0.00326 vs. 0.00316), the red jungle fowls, the present-day domestic chickens experienced a dramatic population size decline during their early domestication. Our analyses suggest that the concomitant bottleneck induced 2.95% more deleterious mutations across chicken genomes compared with red jungle fowls, supporting the "cost of domestication" hypothesis. Particularly, we find that 62.4% of deleterious SNPs in domestic chickens are maintained in heterozygous states and masked as recessive alleles, challenging the power of modern breeding programs to effectively eliminate these genetic loads. Finally, we suggest that positive selection decreases the incidence but increases the frequency of deleterious SNPs in domestic chicken genomes. CONCLUSION: This study reveals a new landscape of demographic history and genomic changes associated with chicken domestication and provides insight into the evolutionary genomic profiles of domesticated animals managed under modern human selection.

19.
Sci Rep ; 11(1): 13121, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162899

RESUMO

This study examines the specific effect of Tween 80 on the conversion of anthracene (ANT) in laccase medium system regarding surfactant chemical changes and mechanism. The conversion rate and degradation products of ANT were investigated in different concentrations of Tween 80 solution. Between Tween 80 concentration 0-40 critical micelle concentrations (CMC), the kinetic parameter-k (h-1) and corresponding half-life T1/2 decreased with increasing concentration. When Tween 80 was above 20 CMC the laccase-medium system converted > 95% of ANT to anthraquinone within 12 h. During the entire enzymatic reaction, the laccase activity in the system increased with increasing Tween 80 concentration. Combined with GC/MS analysis of the product, it was speculated that hydrogens belonging to the ether-oxygen bond and carbon-carbon double bond α-CH of Tween 80, were removed by the laccase-media system, promoting its degradation. Additionally, enhanced activity caused by oxygen free radicals (ROS) such as RO• and ROO•, continuously oxidized Tween 80, which in turn produced free radicals while converting ANT. This study provides new theoretical support toward the application of surfactants in the elimination of polycyclic aromatic hydrocarbons.

20.
Food Chem ; 364: 130382, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34186476

RESUMO

In this work, polyacrylic acid modified ferroferric oxide (Fe3O4-PAA) was synthesized via a one-step hydrothermal method. The magnetic nanospheres modified with carboxyl groups were combined with epsilon-polylysine (EPL) via an EDC/NHS coupling reaction to obtain Fe3O4-PAA-EPL nanospheres. Fe3O4-PAA-EPL was employed as an antibacterial agent against Alicyclobacillus acidoterrestris and characterized by XRD, FTIR, XPS, VSM, SEM and TEM techniques. Experimental results showed the minimum inhibition concentration (MIC) of Fe3O4-PAA-EPL against A. acidoterrestris was 1.25 mg mL-1. Furthermore, A. acidoterrestris treated with Fe3O4-PAA-EPL nanospheres obviously lysed. Morphological analysis of bacteria supported by SEM indicated that the cell membrane of A. acidoterrestris was damaged, revealing that Fe3O4-PAA-EPL is an effective antibacterial agent. Additionally, the nanospheres with excellent magnetism can be simply separated from a reaction system via an external magnet. The construction of magnetic nanospheres with satisfactory antibacterial activity provides an effective and new method to control A. acidoterrestris.


Assuntos
Alicyclobacillus , Nanosferas , Antibacterianos/farmacologia , Fenômenos Magnéticos , Polilisina
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