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1.
Phys Rev Lett ; 133(5): 056001, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39159112

RESUMEN

The natural bulk Van der Waals heterostructure compound 6R-TaS_{2} consists of alternate stacking 1T- and 1H-TaS_{2} monolayers, creating a unique system that incorporates charge-density-wave (CDW) order and superconductivity (SC) in distinct monolayers. Here, after confirming that the 2D nature of the lattice is preserved up to 8 GPa in 6R-TaS_{2}, we documented an unusual evolution of CDW and SC by conducting high-pressure electronic transport measurements. Upon compression, we observe a gradual suppression of CDW within the 1T layers, while the SC exhibits a dome-shaped behavior that terminates at a critical pressure P_{c} around 2.9 GPa. By taking account of the fact that the substantial suppression of SC is concomitant with the complete collapse of CDW order at P_{c}, we argue that the 6R-TaS_{2} behaves like a stack of Josephson junctions and thus the suppressed superconductivity can be attributed to the weakening of Josephson coupling associated with the presence of CDW fluctuations in the 1T layers. Furthermore, the SC reversely enhances above P_{c}, implying the development of emergent superconductivity in the 1T layers after the melting of T-layer CDW orders. These results show that the 6R-TaS_{2} not only provides a promising platform to explore emergent phenomena but also serves as a model system to study the complex interactions between competing electronic states.

2.
Plant Dis ; 2022 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-36366836

RESUMEN

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.

3.
Arch Microbiol ; 204(1): 91, 2021 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-34962581

RESUMEN

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.


Asunto(s)
L-Lactato Deshidrogenasa , Staphylococcus , Antibacterianos/farmacología , Resistencia a Múltiples Medicamentos , L-Lactato Deshidrogenasa/genética , Staphylococcus/genética
4.
BMC Vet Res ; 15(1): 224, 2019 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-31266490

RESUMEN

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 .


Asunto(s)
Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana/efectos de los fármacos , Proteoma/análisis , Staphylococcus/efectos de los fármacos , Tilosina/farmacología , Aldehído Deshidrogenasa/genética , Aldehído Deshidrogenasa/metabolismo , Antibacterianos/farmacología , Proteínas Bacterianas/aislamiento & purificación , Farmacorresistencia Bacteriana/genética , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Proteómica/métodos , Proteínas Ribosómicas/genética , Proteínas Ribosómicas/metabolismo , Staphylococcus/genética , Staphylococcus/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
5.
Proc Natl Acad Sci U S A ; 113(11): 2904-9, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26929327

RESUMEN

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.

6.
Opt Lett ; 43(10): 2288-2291, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29762574

RESUMEN

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.

7.
Phys Rev Lett ; 120(3): 037002, 2018 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-29400497

RESUMEN

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.

8.
Opt Lett ; 42(24): 5129-5132, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-29240154

RESUMEN

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.

9.
Phys Rev Lett ; 117(14): 146402, 2016 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-27740840

RESUMEN

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.

10.
Surg Endosc ; 30(7): 2759-65, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26487219

RESUMEN

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.


Asunto(s)
Colectomía/métodos , Estreñimiento/cirugía , Procedimientos de Cirugía Plástica/métodos , Complicaciones Posoperatorias/epidemiología , Rectocele/cirugía , Vagina/cirugía , Anciano , Pérdida de Sangre Quirúrgica , Estreñimiento/complicaciones , Femenino , Humanos , Laparoscopía/métodos , Persona de Mediana Edad , Tempo Operativo , Calidad de Vida , Rectocele/complicaciones , Estudios Retrospectivos , Resultado del Tratamiento
11.
Int J Biol Macromol ; 277(Pt 1): 133998, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39032905

RESUMEN

Camellia oleifera shells (COS) are commonly discarded as an agricultural by-product. Effective utilization of COS can not only reduce environmental pollution but also enhance the value of the tea-oil industry. The unique composition of COS, with high hemicellulose and low cellulose content, makes it suitable for the production of film materials. In this study, COS holocellulose (COSH) was isolated and treated with four different types of dilute acids (15 % acetic acid, gallic acid, citric acid, and 0.5 % sulfuric acid, 1-24 h, 75°-105 °C) to produce barrier films. Among these, citric acid treatment resulted in the strongest and toughest film. By incorporating a brief ultrasonic pretreatment (15 min, 300 w) prior to the citric acid reaction, translucent films were achieved with impressive mechanical properties, showing tensile strength, Young's modulus and elongation at break up to 75.72 MPa, 3306.11 MPa and 8.01 %, respectively. Through a comprehensive analysis of the structure-property relationships, it was discovered that the combined effects of ultrasonic and citric acid treatments disrupted the integrated holocelluose fiber structure and facilitated the formation of a robust hydrogen bond network during the film preparation process. The resulting films exhibited enhanced water vapor barrier properties, antioxidant capacity, and complete decomposition in soil, suggesting the potential application as wraps for fresh fruits.


Asunto(s)
Camellia , Celulosa , Camellia/química , Celulosa/química , Ondas Ultrasónicas , Antioxidantes/química , Ácido Cítrico/química , Ácidos/química , Resistencia a la Tracción , Vapor , Permeabilidad , Agricultura/métodos
12.
Sci Rep ; 14(1): 25232, 2024 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-39448746

RESUMEN

This study investigates the mechanical, thermal, and water absorption properties of high-density polyethylene (HDPE) composites filled with barley straw and varying amounts of waste rubber. The research aims to develop sustainable materials that repurpose agricultural and industrial waste while addressing resource scarcity and waste management challenges. Composites were prepared using a twin-rotor mixer and hydraulic press, with waste rubber content varying from 0 to 20 wt%. Mechanical properties were evaluated through tensile testing, thermal behavior was analyzed using TGA, DTG, and DSC, and long-term water absorption was measured. Results show that increasing waste rubber content from 0 to 20% led to a decrease in tensile strength (11.3 to 8.9 MPa) and tensile modulus (1760 to 790 MPa), while relative extension increased (2.4-5.9%). Thermal analysis revealed a slight reduction in onset degradation temperature (270 °C to 240 °C) and increased char residue (8-18%) with higher rubber content. Water absorption decreased significantly, from 12 to 13% to 6-7% after 600 h of immersion, as waste rubber content increased. These findings demonstrate that incorporating waste rubber into HDPE/barley straw composites results in materials with enhanced flexibility and water resistance at the cost of some strength and stiffness. In conclusion, the results of this study offer a clear pathway for the development of sustainable polymer composites that have broad potential applications across industries like construction, marine infrastructure, automotive, and packaging. By replacing traditional, resource-intensive materials with eco-friendly alternatives, these composites not only provide functional benefits but also support global efforts toward sustainable development and environmental conservation.

13.
Food Funct ; 15(9): 4805-4817, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38563411

RESUMEN

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.


Asunto(s)
Heces , Fermentación , Microbioma Gastrointestinal , Xantófilas , Microbioma Gastrointestinal/efectos de los fármacos , Humanos , Xantófilas/metabolismo , Xantófilas/farmacología , Heces/microbiología , Masculino , Adulto , Bacterias/metabolismo , Bacterias/clasificación , Bacterias/genética
14.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(8): 961-967, 2024 Aug 15.
Artículo en Zh | MEDLINE | ID: mdl-39175318

RESUMEN

Objective: To compare the effectiveness of biplanar vertical fixation and inverted triangle fixation with hollow screw for Pauwels type Ⅲ femoral neck fracture in young and middle-aged patients. Methods: The clinical data of 55 young and middle-aged patients with Pauwels type Ⅲ femoral neck fracture between June 2021 and December 2022 was retrospectively analyzed. All patients were treated with closed reduction and internal fixation with hollow screws, 25 cases were treated with biplanar vertical fixation (study group), 30 cases with inverted triangle fixation (control group). There was no significant difference in gender, age, affected side, cause of injury, underlying diseases, and time from injury to operation between the two groups ( P>0.05). The operation time, intraoperative blood loss, fluoroscopy times, guide needle puncture times, starting time of weight bearing, time of full weight bearing, time of fracture healing, and complications were recorded and compared between the two groups. The hip joint function was evaluated by Harris score at 1 day, 6 months, 12 months after operation, and at last follow-up, and the pain relief was evaluated by visual analogue scale (VAS) score. The femoral neck shortening was measured on the X-ray film at last follow-up. Results: All patients were followed up 12-31 months (mean, 22.0 months), and there was no significant difference in follow-up time between the two groups ( P>0.05). The operation time, intraoperative blood loss, and fluoroscopy times in the study group were higher than those in the control group, but the difference was not significant ( P>0.05). The guide needle puncture times in the study group was more than that in the control group, and the time of starting weight bearing and the time of full weight bearing in the study group were shorter than those in the control group, the differences were significant ( P<0.05). Bony healing was achieved in both groups, and there was no significant difference in fracture healing time between the two groups ( P>0.05). No osteonecrosis of the femoral head and incision-related complication was found in the two groups during follow-up, and the femoral neck shortening length in the study group was significantly shorter than that in the control group at last follow-up ( P<0.05). There was no significant difference in Harris score between the two groups at 1 day after operation ( P>0.05), and the Harris score of the study group was significantly better than that of the control group at other time points ( P<0.05); there was no significant difference in VAS score between the two groups at each time point after operation ( P>0.05). Conclusion: Compared with the inverted triangle fixation, the treatment of Pauwels type Ⅲ femoral neck fracture with biplanar vertical fixation can effectively reduce femoral neck shortening without affecting fracture healing, and improve hip joint function in early stage.


Asunto(s)
Tornillos Óseos , Fracturas del Cuello Femoral , Fijación Interna de Fracturas , Humanos , Fracturas del Cuello Femoral/cirugía , Fijación Interna de Fracturas/métodos , Fijación Interna de Fracturas/instrumentación , Persona de Mediana Edad , Masculino , Femenino , Resultado del Tratamiento , Adulto , Curación de Fractura , Tempo Operativo
15.
Adv Sci (Weinh) ; : e2408044, 2024 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-39455287

RESUMEN

Osteoporotic fractures are characterized by abnormal inflammation, deterioration of the bone microenvironment, weakened mechanical properties, and difficulties in osteogenic differentiation. The chronic inflammatory state characterized by aging macrophages leads to delayed or non-healing of the fracture or even the formation of bone defects. The current bottleneck in clinical treatment is to achieve strong fixation of the comminuted bone fragments and effective regulation of the complex microenvironment of aging macrophages. Inspired by cement and gravel in concrete infrastructure, a biomimetic bone glue with poly(lactic-co-glycolic acid) microspheres is developed and levodopa/oxidized chitosan hydrogel stabilized on an organic-inorganic framework of nanohydroxyapatite, named DOPM. DOPM is characterized via morphological and mechanical characterization techniques, in vitro experiments with bone marrow mesenchymal stromal cells, and in vivo experiments with an aged SD rat model exhibiting osteoporotic bone defects. DOPM exhibited excellent adhesion properties, good biocompatibility, and significant osteogenic differentiation. Transcriptomic analysis revealed that DOPM improved the inflammatory microenvironment by inhibiting the NF-κB signaling pathway and promoting aging macrophage polarization toward M2 macrophages, thus significantly accelerating bone defect repair and regeneration. This biomimetic bone glue, which enhances osteointegration and reestablishes the homeostasis of aging macrophages, has potential applications in the treatment of osteoporotic bone defects.

16.
Polymers (Basel) ; 15(4)2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36850175

RESUMEN

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 [...].

17.
Infect Drug Resist ; 16: 1345-1355, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36925724

RESUMEN

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.

18.
Polymers (Basel) ; 15(8)2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37112109

RESUMEN

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.

19.
Virus Genes ; 45(3): 463-73, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22843323

RESUMEN

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.


Asunto(s)
Circovirus/clasificación , Circovirus/genética , Variación Genética , Genoma Viral , Filogenia , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Proteínas de la Cápside/genética , China , Circovirus/patogenicidad , ADN Viral/genética , Evolución Molecular , Tamaño del Genoma , Genotipo , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Recombinación Genética , Selección Genética , Homología de Secuencia de Ácido Nucleico , Porcinos/virología
20.
Zhonghua Yi Xue Za Zhi ; 92(36): 2553-5, 2012 Sep 25.
Artículo en Zh | MEDLINE | ID: mdl-23158797

RESUMEN

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.


Asunto(s)
Anastomosis Quirúrgica/efectos adversos , Fuga Anastomótica/etiología , Laparoscopía/efectos adversos , Complicaciones Posoperatorias/etiología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Colorrectales/cirugía , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
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