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1.
Plant Dis ; 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36366836

RESUMO

The variegated leaves and fragrant flowers of Daphne odora var. marginata Mak. make it a popular garden plant. In May 2020, we found diseased D. odora plants in a greenhouse at the Ganzhou Vegetable and Flower Research Institute, in southeast China; 72% of 1800 plants had Phytophthora blight-like symptoms-shrunken stems, black withered branches, wilted and dropped leaves (Fig 1a), and rotted and dark green roots. The root and stem tissue surfaces were disinfected with 75% ethanol for 30 s followed by 0.1% HgCl2 for 1 min, rinsed thrice with sterile water, and cultured on potato-dextrose agar (PDA) medium at 25°C. Mycelia from the diseased tissue were subcultured on fresh PDA medium, providing three colonies. White colonies (~4.1 mm) were formed after 10 days at 25°C (Fig 1b). Sporangia and chlamydospores were induced by placing actively growing mycelia on PDA medium at 25°C for ~30 days and then at 45°C for ~3 days. Sporangia were ovoid to spherical and 19.33 × 20.99 µm in size (Fig 1c), whereas chlamydospores were spherical and 15.68 × 16.10 µm in size (Fig 1d). All three colonies resembled Phytophthora spp. Genomic DNA was extracted from isolates using the Ezup Column Fungi Genomic DNA Purification Kit (Sangon Biotech [Shanghai] Co. Ltd.), and rDNA-ITS and ß-tubulin were amplified and sequenced. BLAST analysis (GenBank) revealed that the ITS (Accession No. MZ676071) and ß-tubulin (MZ748503) sequences of isolates shared the highest similarity (99-100%) with those of Phytophthora nicotianae (Duccio et al. 2015). A phylogenetic tree of the relationship between our isolate hjt3 and its close relatives within the P. nicotianae species was constructed using the MEGA X neighbor-joining method (Fig 2). The pathogen was identified as P. nicotianae based on morphological and molecular characteristics. Sequencing results of the three samples were consistent, all indicating P. nicotianae. A specimen (JXAU-H2020245) was deposited in the Herbarium of the College of Agronomy, Jiangxi Agricultural University. To confirm pathogenicity, 9-month-old healthy D. odora plants were used for stem and soil inoculation. Stems were cut ~5 cm from the soil with sterilized scalpels and inoculated with 0.8 cm diameter PDA plugs containing actively growing mycelia of isolate hjt3. The soil was sterilized and 0.8 cm PDA plugs containing actively growing mycelia were buried in the soil at ~5 cm; the mycelia were in contact with the roots. Plants in both groups were treated equally; those inoculated with sterile PDA plugs served as controls. There were six plants in each group, with each experiment performed in triplicate. All plants were incubated in a greenhouse at 25-28°C. The stems shrank and began to rot rapidly after 7 days (Fig 3) and the branches turned black and withered within 2 weeks. After soil inoculation, the stems of the inoculated plants blackened and rotted in ~20 days (Fig 4) and the roots rotted and turned dark green (Fig 5). These symptoms rapidly spread to the branches. The control plants did not exhibit any symptoms. Reisolated colonies showed the same morphological traits as the isolates used for inoculation; no target colonies were isolated from the control plants. Phytophthora blight caused by P. nicotianae on D. odora has been reported in Italy (Garibaldi A, 2009) and Korea (Kwon et al. 2005). This is the first detection in China. Therefore, Phytophthora blight on D. odora caused by P. nicotianae should be monitored and controlled to promote the development of the D. odora industry.

2.
Arch Microbiol ; 204(1): 91, 2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-34962581

RESUMO

Staphylococcus xylosus is a gram-positive bacterium that has attracted much attention due to its increasing clinical appearance, frequently associated with serious multidrug resistance cases. L-lactate dehydrogenase (LDH) has been related to drug resistance in several bacterial species. However, the mechanism of multidrug resistance in S. xylosus remains unclear as well as the involvement of LDH in such resistance. To explore the relationship between multidrug resistance and LDH in S. xylosus, we used tylosin-resistant S. xylosus as the parent strain to construct ldh knockout and complemented strains. Then, we tested their resistance to macrolides, lincosamides, tetracyclines, and aminoglycosides. In addition, the enzyme activity, metabolite content, and transcriptional level of key genes involved in the TCA cycle and thioredoxin system were determined to clarify the mechanism of resistance. We observed that the resistance to multiple antibiotics increased significantly after ldh knockout, especially that to lincomycin, whereas antibiotic sensitivity was partially restored in the complemented strain. The levels of pyruvate, nicotinamide adenine dinucleotide, and reactive oxygen species decreased significantly upon ldh knockout, and the activity of isocitrate dehydrogenase and malate dehydrogenase decreased. These results indicate that the lack of LDH promotes multidrug resistance in S. xylosus by inhibiting the TCA cycle and regulating the thioredoxin system.


Assuntos
L-Lactato Desidrogenase , Staphylococcus , Antibacterianos/farmacologia , Resistência a Múltiplos Medicamentos , L-Lactato Desidrogenase/genética , Staphylococcus/genética
3.
BMC Vet Res ; 15(1): 224, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266490

RESUMO

BACKGROUND: As a kind of opportunist pathogen, Staphylococcus xylosus (S. xylosus) can cause mastitis. Antibiotics are widely used for treating infected animals and tylosin is a member of such group. Thus, the continuous use of antibiotics in dairy livestock enterprise will go a long way in increasing tylosin resistance. However, the mechanism of tylosin-resistant S. xylosus is not clear. Here, isobaric tag for relative and absolute quantitation (iTRAQ)-based quantitative proteomics methods was used to find resistance-related proteins. RESULTS: We compared the differential expression of S. xylosus in response to tylosin stress by iTRAQ. A total of 155 proteins (59 up-regulated, 96 down-regulated) with the fold-change of >1.2 or <0.8 (p value ≤0.05) were observed between the S. xylosus treated with 1/2 MIC (0.25 µg/mL) tylosin and the untreated S. xylosus. Bioinformatic analysis revealed that these proteins play important roles in stress-response and transcription. Then, in order to verify the relationship between the above changed proteins and mechanism of tylosin-resistant S. xylosus, we induced the tylosin-resistant S. xylosus, and performed quantitative PCR analysis to verify the changes in the transcription proteins and the stress-response proteins in tylosin-resistant S. xylosus at the mRNA level. The data displayed that ribosomal protein L23 (rplw), thioredoxin(trxA) and Aldehyde dehydrogenase A(aldA-1) are up-regulated in the tylosin-resistant S. xylosus, compared with the tylosin-sensitive strains. CONCLUSION: Our findings demonstrate the important of stress-response and transcription in the tylosin resistance of S. xylosus and provide an insight into the prevention of this resistance, which would aid in finding new medicines .


Assuntos
Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana/efeitos dos fármacos , Proteoma/análise , Staphylococcus/efeitos dos fármacos , Tilosina/farmacologia , Aldeído Desidrogenase/genética , Aldeído Desidrogenase/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/isolamento & purificação , Farmacorresistência Bacteriana/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Proteômica/métodos , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Staphylococcus/genética , Staphylococcus/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
4.
Proc Natl Acad Sci U S A ; 113(11): 2904-9, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26929327

RESUMO

As a new type of topological materials, ZrTe5 shows many exotic properties under extreme conditions. Using resistance and ac magnetic susceptibility measurements under high pressure, while the resistance anomaly near 128 K is completely suppressed at 6.2 GPa, a fully superconducting transition emerges. The superconducting transition temperature Tc increases with applied pressure, and reaches a maximum of 4.0 K at 14.6 GPa, followed by a slight drop but remaining almost constant value up to 68.5 GPa. At pressures above 21.2 GPa, a second superconducting phase with the maximum Tc of about 6.0 K appears and coexists with the original one to the maximum pressure studied in this work. In situ high-pressure synchrotron X-ray diffraction and Raman spectroscopy combined with theoretical calculations indicate the observed two-stage superconducting behavior is correlated to the structural phase transition from ambient Cmcm phase to high-pressure C2/m phase around 6 GPa, and to a mixture of two high-pressure phases of C2/m and P-1 above 20 GPa. The combination of structure, transport measurement, and theoretical calculations enable a complete understanding of the emerging exotic properties in 3D topological materials under extreme environments.

5.
Opt Lett ; 43(10): 2288-2291, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29762574

RESUMO

Non-polar ZnO thin films are grown on m-plane sapphire substrates by plasma-assisted molecular beam epitaxy. Emission enhancement from non-polar ZnO thin films coated with Al/AlOx has been studied by photoluminescence spectroscopy. AlOx has been used to mediate the surface plasmon (SP) energy of Al nanoparticles. Taking advantage of the resonant coupling between the UV emission of non-polar ZnO film and Al nanoparticle SPs, an 84-fold enhancement of the UV emission and an 8.3-fold enhancement of internal quantum efficiency (ηint) have been achieved under the optimized sputtering time and energy of SPs.

6.
Phys Rev Lett ; 120(3): 037002, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29400497

RESUMO

As a follow-up of our previous work on pressure-induced metallization of the 2H_{c}-MoS_{2} [Chi et al., Phys. Rev. Lett. 113, 036802 (2014)PRLTAO0031-900710.1103/PhysRevLett.113.036802], here we extend pressure beyond the megabar range to seek after superconductivity via electrical transport measurements. We found that superconductivity emerges in the 2H_{a}-MoS_{2} with an onset critical temperature T_{c} of ca. 3 K at ca. 90 GPa. Upon further increasing the pressure, T_{c} is rapidly enhanced beyond 10 K and stabilized at ca. 12 K over a wide pressure range up to 220 GPa. Synchrotron x-ray diffraction measurements evidenced no further structural phase transition, decomposition, and amorphization up to 155 GPa, implying an intrinsic superconductivity in the 2H_{a}-MoS_{2}. DFT calculations suggest that the emergence of pressure-induced superconductivity is intimately linked to the emergence of a new flat Fermi pocket in the electronic structure. Our finding represents an alternative strategy for achieving superconductivity in 2H-MoS_{2} in addition to chemical intercalation and electrostatic gating.

7.
Opt Lett ; 42(24): 5129-5132, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29240154

RESUMO

Zn0.78Mg0.22O thin films were grown on a-plane sapphire substrates by plasma-assisted molecular beam epitaxy. Compared with ZnO, the crystal quality of Zn0.78Mg0.22O thin films degrades significantly, which results in low internal quantum efficiency (ηint). Besides improving the quality of Zn0.78Mg0.22O, an effective method has been used to enhance the internal quantum efficiency and the UV emission of Zn0.78Mg0.22O by sputtering Al nanoparticles. Taking advantage of the resonant coupling between UV emission of Zn0.78Mg0.22O film and Al nanoparticle surface plasmons (SPs), a 59-fold enhancement of the UV emission and a 3.5-fold enhancement of ηint has been achieved under the optimized sputtering time. Moreover, the enhancement ratio is stable after two months. It paves a facile way in fabricating high-efficiency UV optoelectronic devices.

8.
Phys Rev Lett ; 117(14): 146402, 2016 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-27740840

RESUMO

We report a new pressure-induced phase in TaAs with different Weyl fermions than the ambient structure with the aid of theoretical calculations, experimental transport and synchrotron structure investigations up to 53 GPa. We show that TaAs transforms from an ambient I4_{1}md phase (t-TaAs) to a high-pressure hexagonal P-6m2 (h-TaAs) phase at 14 GPa, along with changes of the electronic state from containing 24 Weyl nodes distributed at two energy levels to possessing 12 Weyl nodes at an isoenergy level, which substantially reduces the interference between the surface and bulk states. The new pressure-induced phase can be reserved upon releasing pressure to ambient condition, which allows one to study the exotic behavior of a single set of Weyl fermions, such as the interplay between surface states and other properties.

9.
Surg Endosc ; 30(7): 2759-65, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26487219

RESUMO

BACKGROUND: Slow-transit constipation complicated with rectocele is a mixed constipation difficult to treat by surgery. Different hospitals and surgeons may employ different surgical procedures. The present study aims to compare the efficacy of laparoscopic subtotal colectomy (LSC) with posterior vaginal suspension and LSC with transvaginal repair for patients having refractory slow-transit constipation complicated with rectocele. METHODS: This paper is a retrospective study of 64 patients having refractory slow-transit constipation complicated with rectocele. Admitted from January 2002 to December 2012, the 64 patients were non-randomly divided into two groups: patients who underwent LSC with posterior vaginal suspension (Group A, 36 patients) and patients who underwent LSC with transvaginal repair (Group B, 28 patients). RESULTS: There was no statistically significant difference (P > 0.05) in preoperative general characteristics and Wexner constipation score between Group A and Group B. There was no statistically significant difference (P > 0.05) in operative time and intraoperative blood loss between the two groups. One month after the surgery, there was no statistically significant difference (P > 0.05) in early postoperative complications, constipation recurrence rate, degree of improvement in constipation symptoms, and Wexner constipation score between the two groups. But 1-year follow-up results show that there was statistically significant difference (P < 0.05) in constipation recurrence rate, gastrointestinal quality of life index, the degree of improvement in constipation symptoms, and Wexner constipation score between the two groups. CONCLUSION: Compared with the LSC with transvaginal repair, the LSC with posterior vaginal suspension demonstrated better efficacy in treating refractory slow-transit constipation complicated with rectocele.


Assuntos
Colectomia/métodos , Constipação Intestinal/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Complicações Pós-Operatórias/epidemiologia , Retocele/cirurgia , Vagina/cirurgia , Idoso , Perda Sanguínea Cirúrgica , Constipação Intestinal/complicações , Feminino , Humanos , Laparoscopia/métodos , Pessoa de Meia-Idade , Duração da Cirurgia , Qualidade de Vida , Retocele/complicações , Estudos Retrospectivos , Resultado do Tratamento
10.
Food Funct ; 15(9): 4805-4817, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38563411

RESUMO

Fucoxanthin, a carotenoid exclusively derived from algae, exerts its bioactivities with the modulation of the gut microbiota in mice. However, mechanisms through which fucoxanthin regulates the gut microbiota and its derived metabolites/metabolism in humans remain unclear. In this study, we investigated the effects of fucoxanthin on the gut microbiota and metabolism of non-obese individuals using an in vitro simulated digestion-fermentation cascade model. The results showed that about half of the fucoxanthin was not absorbed in the intestine, thus reaching the colon. The gut microbiota from fecal samples underwent significant changes after 48 or 72 hours in vitro fermentation. Specifically, fucoxanthin significantly enhanced the relative abundance of Bacteroidota and Parabacteroides, leading to improved functions of the gut microbiota in its development, glycan biosynthesis and metabolism as well as in improving the digestive system, endocrine system and immune system. The recovery of fucoxanthin during fermentation showed a decreasing trend with the slight bio-conversion of fucoxanthinol. Notably, fucoxanthin supplementation significantly altered metabolites, especially bile acids and indoles in the simulated human gut ecosystem. Correlation analysis indicated the involvement of the gut microbiota in the manipulation of these metabolites by fucoxanthin. Moreover, all these altered metabolites revealed the improvement in the capacity of fucoxanthin in manipulating gut metabolism, especially lipid metabolism. Overall, fucoxanthin determinedly reshaped the gut microbiota and metabolism, implying its potential health benefits in non-obese individuals.


Assuntos
Fezes , Fermentação , Microbioma Gastrointestinal , Xantofilas , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Xantofilas/metabolismo , Xantofilas/farmacologia , Fezes/microbiologia , Masculino , Adulto , Bactérias/metabolismo , Bactérias/classificação , Bactérias/genética
11.
Polymers (Basel) ; 15(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36850175

RESUMO

The ongoing transition from a linear to a circular, low-carbon bioeconomy is crucial for reducing the consumption of global natural resources, minimizing waste generation, reducing carbon emissions, and creating more sustainable growth and jobs, the prerequisites necessary to achieve climate neutrality targets and stop biodiversity loss [...].

12.
Infect Drug Resist ; 16: 1345-1355, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36925724

RESUMO

Purpose: Staphylococcus epidermidis has become one of the most common causes of septicemia. Meanwhile, S. epidermidis has acquired resistance to many antibiotics. Among these, methicillin-resistant S. epidermidis (MRSE) were frequently isolated. Similar to methicillin resistant Staphylococcus aureus (MRSA), they also exhibited multi-resistance, which presented a danger to human health. Patrinia scabiosaefolia as traditional Chinese medicine had strong antibacterial activity against MRSE. However, the mechanism of P. scabiosaefolia against MRSE is not clear. Methods: Here, the morphology of cell wall and cell membrane, production of ß-lactamase and PBP2, energy metabolism, antioxidant system were systematically studied. Results: The data showed that P. scabiosaefolia damaged the cell wall and membrane. In addition, ß-lactamase, energy metabolism and antioxidant system were involved in mechanisms of P. scabiosaefolia against MRSE. Conclusion: These observations provided new understanding of P. scabiosaefolia against MRSE to control MRSE infections.

13.
Polymers (Basel) ; 15(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37112109

RESUMO

The biodegradation path and mechanism of wood varies depending on diverse fungi and tree species, as fungi possess selectivity in degradation of versatile wood components. This paper aims to clarify the actual and precise selectivity of white and brown rot fungi and the biodegradation effects on different tree species. Softwood (Pinus yunnanensis and Cunninghamia lanceolata) and hardwood (Populus yunnanensis and Hevea brasiliensis) were subjected to a biopretreating process by white rot fungus Trametes versicolor, and brown rot fungi Gloeophyllum trabeum and Rhodonia placenta with various conversion periods. The results showed that the white rot fungus Trametes versicolor had a selective biodegradation in softwood, which preferentially convert wood hemicellulose and lignin, but cellulose was retained selectively. Conversely, Trametes versicolor achieved simultaneous conversion of cellulose, hemicellulose and lignin in hardwood. Both brown rot fungi species preferentially converted carbohydrates, but R. placenta had a selectivity for the conversion of cellulose. In addition, morphological observation showed that the microstructures within wood changed significantly, and the enlarged pores and the improved accessibility could be beneficial for the penetration and accessibility of treating substrates. The research outcomes could serve as fundamental knowhows and offer potentials for effective bioenergy production and bioengineering of bioresources, and provide a reference for further application of fungal biotechnology.

14.
Virus Genes ; 45(3): 463-73, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22843323

RESUMO

Porcine circovirus type 2 (PCV2) infection causes postweaning multisystemic wasting syndrome and porcine circovirus-associated diseases in many regions. A total of 77 sequences, including 31 sampled from Henan province of China, were retrieved from GenBank and subjected to amino acid variation and phylogenetic analyses. The two PCV genotypes prevailing in Henan were PCV-2a and PCV-2b with PCV-2b accounting for 93.5 % (29/31) of the Henan isolates. The 31 Henan isolates all shared between 92.7 and 100 % sequence similarity. Amino acid variation analysis of the capsid protein revealed that Henan PCV2 strains tended to accumulate more substitutions within epitopic regions-a substitution pattern consistent with host immune system-mediated selection of virus immune escape variants. The analysed PCV sequences carry evidence of at least six unique recombination events. Selective pressure analysis of the relative recombination-free ORF2 sequences of these viruses revealed evidence of sites that are likely evolving in response to host-driven immune pressures-a finding that coupled with information on the prevalent diversity in Henan PCV2 isolates of known immunoreactive genomic loci will aid in future studies aiming to assess the evolutionary responses of PCV2 in China to the widespread deployment of anti-PCV vaccines in the country.


Assuntos
Circovirus/classificação , Circovirus/genética , Variação Genética , Genoma Viral , Filogenia , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Proteínas do Capsídeo/genética , China , Circovirus/patogenicidade , DNA Viral/genética , Evolução Molecular , Tamanho do Genoma , Genótipo , Dados de Sequência Molecular , Fases de Leitura Aberta , Recombinação Genética , Seleção Genética , Homologia de Sequência do Ácido Nucleico , Suínos/virologia
15.
Zhonghua Yi Xue Za Zhi ; 92(36): 2553-5, 2012 Sep 25.
Artigo em Zh | MEDLINE | ID: mdl-23158797

RESUMO

OBJECTIVE: To explore the causes of postoperative anastomotic leakage of colorectal cancer. METHODS: A total of 1462 cases with colorectal cancer undergoing laparoscopic operation and intestinal anastomosis at our department over the last decade were analyzed retrospectively. Data analysis was performed with SPSS 13.0. The risk factors were analyzed by binary Logistic regression while the annual incidence of anastomotic leakage by trend χ(2) test. RESULTS: Thirty anastomotic leakage occurred in 1462 cases with an incidence rate of 2.1%. There were significant correlations of anastomotic leakage with body built, tumor location, tumor size, operation time (χ(2) = 6.117, 50.167, 36.693, 4.481, P = 0.013, 0.000, 0.000, 0.034). However, there was no correction with gender, age or histological type (P = 0.871, 0.775, 1.000). Then the significance check of binary Logistic regression equation was performed. Tumor location was an independent risk factor of postoperative anastomotic leakage for colorectal cancer. The relative risk was 2.056. The annual incidence of anastomotic leakage was statistically insignificant (χ(2) = 1.827, P = 0.176). And the difference was. CONCLUSIONS: The occurrence of anastomotic leakage after colorectal cancer surgery is significantly correlated with body built, tumor location, tumor size and operation time. And tumor location below peritoneal reversal is an independent risk factor of anastomotic leakage.


Assuntos
Anastomose Cirúrgica/efeitos adversos , Fístula Anastomótica/etiologia , Laparoscopia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
16.
J Colloid Interface Sci ; 606(Pt 1): 192-203, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34388570

RESUMO

Strain-sensitive and conductive hydrogels have attracted extensive research interest due to their potential applications in various fields, such as healthcare monitoring, human-machine interfaces and soft robots. However, low electrical signal transmission and poor tensile properties still limit the application of flexible sensing hydrogels in large amplitude and high frequency motion. In this study, a novel ionic liquid segmental polyelectrolyte hydrogel consisting of acrylic acid (AAc), 1-vinyl-3-butylimidazolium bromide (VBIMBr) and aluminum ion (Al3+) was prepared by molecular design and polymer synthesis. The cationic groups and amphiphilicity of ionic liquid chain segments effectively improve the tensile behavior of the polyelectrolyte hydrogel, with a maximum tensile strength of 0.16 MPa and a maximum breaking strain of 604%. The introduction of ionic liquid segments increased the current carrying concentration of polyelectrolyte hydrogel, and the conductivity reached the initial 4.8 times (12.5 S/m), which is a necessary condition for detecting various amplitude and high frequency limb movements. The flexible electronic sensor prepared by this polyelectrolyte hydrogel efficiently detects the movement of different parts of the human body stably and sensitively, even in extreme environment (-20 °C). These outstanding advantages demonstrate the great potential of this hydrogel in healthcare monitoring and wearable flexible strain sensors.


Assuntos
Líquidos Iônicos , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Humanos , Hidrogéis , Resistência à Tração
17.
Int J Biol Macromol ; 222(Pt A): 1211-1220, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36155785

RESUMO

Currently, hydrogel sensors for health monitoring require external tapes, bandages or adhesives to immobilize them on the surface of human skin. However, these external fixation methods easily lead to skin allergic reactions and the decline of monitoring accuracy. A simple strategy to solve this problem is to endow hydrogel sensors with good adhesion. Inspired by the starch paste adhesion mechanism, a biomass-based hydrogel with good conductivity and high repetitive adhesion strength was prepared by introducing modified starch into polyacrylic acid hydrogel system. The properties of biomass-based hydrogels could be controlled by changing the proportion of amylose and amylopectin. The biomass-based hydrogel exhibited a variety of excellent properties, including good stretchability (1290 %), high adhesion strength (pig skin: 46.51 kPa) and conductivity (2.3 S/m). Noticeably, the repeated adhesive strength of biomass-based hydrogel did not decrease with the increase of adhesion times. The strain sensor based on the biomass-based hydrogel could accurately monitor the large-scale and small movements of the human body, and had broad application prospects in the field of flexible wearable devices.


Assuntos
Hidrogéis , Amido , Humanos , Animais , Suínos , Biomassa , Condutividade Elétrica , Adesivos
18.
Infect Drug Resist ; 15: 883-893, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35281570

RESUMO

Purpose: As a kind of opportunist pathogen, Staphylococcus epidermidis (MRSE) can cause nosocomial infections and easily evolve into resistant bacteria. Among these, methicillin-resistant Staphylococcus epidermidis (MRSE) exhibit significantly higher rates. Our previous study showed that Patrinia scabiosaefolia (PS) possessed strong antibacterial activity against MRSE. However, the mechanism of PS against MRSE is not clear. Methods: Here, a tandem mass tag-based (TMT) proteomic analysis was performed to elucidate the potential mechanism of PS against MRSE. We compared the differential expression proteins of MRSE under PS stress. Results: Based on a fold change of >1.2 or < 1/1.2 (with p value set at <0.05), a total of 248 proteins (128 up-regulated proteins, 120 down-regulated proteins) were identified. Bioinformatic analysis showed that proteins including arginine deiminase (arcA), ornithine carbamoyltransferase (arcB) and carbamate kinase (arcC), serine-tRNA ligase (serS), phenylalanine-tRNA ligase beta and subunit (pheT), DltD (dlt), d-alanyl carrier protein (dlt), accumulation-associated protein (SasG), serine-aspartate repeat-containing protein C (SdrC) and hemin transport system permease protein HrtB (VraG) played important roles in mechanism of PS against MRSE. Conclusion: In summary, these results indicated that arginine deiminase pathway (ADI) pathway, protein synthesis, cell wall synthesis, biofilm formation and uptake of iron were related to mechanisms of PS against MRSE. Our findings provide an insight into the the mechanism of PS against MRSE, and may be valuable in offering new targets to develop more anti-MRSE drugs.

19.
J Phys Condens Matter ; 34(31)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35636404

RESUMO

Two-dimensional transition metal dichalcogenides (TMDs) are important materials for promising electronic devices because they usually exhibit excellent and highly tunable electronic properties. Here, we report on the pressure-driven electronic phase transition in a TMD 1T-Co1.06Te2. High-pressure transport measurements reveal a sign reversal of the Hall coefficients at a critical point ofPC∼ 32 GPa, evidencing a transition from hole band(s) dominated transport into one that is dominated by electron band(s). Synchrotron x-ray diffraction experiments demonstrate that no structural phase transition occurs below 46.3 GPa, indicating an electronic origin of the transition. Moreover, a kink anomaly of the lattice constant ratioc/ais also observed atP=PC. These results might indicate a Lifshitz transition which refers to a change of Fermi surface topology in absence of structural transition.

20.
J Colloid Interface Sci ; 628(Pt A): 287-298, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35940139

RESUMO

The preparation of hydrogel-based wearable sensors for underwater application with high mechanical properties and electrical conductivity is an urgent challenge. Here, a supramolecular hydrogel based on polyionic liquids was designed and prepared for underwater sensing. The introduction of functional ionic liquid structures effectively increased the supramolecular interaction in the hydrogel network, which made the hydrogel successfully resist the interference of external water molecules. Depending on the effect of charge and hydrophobic interactions, this supramolecular hydrogel sensor exhibited high tensile (759 %), high tensile strength (0.23 MPa), high sensitivity (GF = 10.76) and extensive antibacterial properties, even in seawater environment. The obtained hydrogel sensor successfully monitored the swimming posture, which was helpful to digitally reflect the limb movement of athletes during underwater sports. This work made progress in the field of underwater wearable sensors based on hydrogels, and this design of multifunctional hydrogel provided a new idea for the development of functional sensors.


Assuntos
Hidrogéis , Líquidos Iônicos , Antibacterianos , Condutividade Elétrica , Humanos , Hidrogéis/química , Água
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