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1.
Int J Biol Macromol ; : 133517, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960251

RESUMO

Reducing the risk of wound infection is an urgent issue health priority. Antibacterial polysaccharide-based hydrogels have attracted great attention for infectious wounds, attributed to their safe antimicrobial performance and natural non-toxicity and biodegradability advantages. In this study, the "all-in-one" self-adaptive and injectable cationic guar gum (CG)-based polysaccharide hydrogels (FA-TOB/CG) loaded with bioactive complexes were developed for infectious wound healing. The constructed antioxidant and antibacterial ferulic acid (FA)-tobramycin (TOB) bioactive complexes (FA-TOB) were used as the cross-linking agent and introduced into the CG matrix to construct the FA-TOB/CG hydrogel with a three-dimensional porous structure. The sterilization rates of FA-TOB/CG hydrogel against S. aureus and E. coli reached 98 % and 80 % respectively. In addition, the FA-TOB/CG also exhibits enhanced antioxidant performances (DPPH: > 40 %; ABTS: > 90 %; ·OH: > 50 %). More importantly, FA-TOB/CG hydrogel also showed the ability to sustain the release of FA and TOB. These superiorities of the FA-TOB/CG hydrogel enabled it to provide a moist wound environment and promote wound healing by eliminating bacteria, modulating the local inflammatory response, and accelerating collagen deposition and vascular regeneration. Thus, this study may enlarge a new sight for developing multifunctional dressings by incorporating bioactive complexes into polysaccharide hydrogels for infected wounds.

3.
BMC Plant Biol ; 24(1): 566, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38880875

RESUMO

BACKGROUND: Plants can retain atmospheric particulate matter (PM) through their unique foliar microstructures, which has a profound impact on the phyllosphere microbial communities. Yet, the underlying mechanisms linking atmospheric particulate matter (PM) retention by foliar microstructures to variations in the phyllosphere microbial communities remain a mystery. In this study, we conducted a field experiment with ten Ulmus lines. A series of analytical techniques, including scanning electron microscopy, atomic force microscopy, and high-throughput amplicon sequencing, were applied to examine the relationship between foliar surface microstructures, PM retention, and phyllosphere microbial diversity of Ulmus L. RESULTS: We characterized the leaf microstructures across the ten Ulmus lines. Chun exhibited a highly undulated abaxial surface and dense stomatal distribution. Langya and Xingshan possessed dense abaxial trichomes, while Lieye, Zuiweng, and Daguo had sparsely distributed, short abaxial trichomes. Duomai, Qingyun, and Lang were characterized by sparse stomata and flat abaxial surfaces, whereas Jinye had sparsely distributed but extensive stomata. The mean leaf retention values for total suspended particulate (TSP), PM2.5, PM2.5-10, PM10-100, and PM> 100 were 135.76, 6.60, 20.10, 90.98, and 13.08 µg·cm- 2, respectively. Trichomes substantially contributed to PM2.5 retention, while larger undulations enhanced PM2.5-10 retention, as evidenced by positive correlations between PM2.5 and abaxial trichome density and between PM2.5-10 and the adaxial raw microroughness values. Phyllosphere microbial diversity patterns varied among lines, with bacteria dominated by Sediminibacterium and fungi by Mycosphaerella, Alternaria, and Cladosporium. Redundancy analysis confirmed that dense leaf trichomes facilitated the capture of PM2.5-associated fungi, while bacteria were less impacted by PM and struggled to adhere to leaf microstructures. Long and dense trichomes provided ideal microhabitats for retaining PM-borne microbes, as evidenced by positive feedback loops between PM2.5, trichome characteristics, and the relative abundances of microorganisms like Trichoderma and Aspergillus. CONCLUSIONS: Based on our findings, a three-factor network profile was constructed, which provides a foundation for further exploration into how different plants retain PM through foliar microstructures, thereby impacting phyllosphere microbial communities.


Assuntos
Microbiota , Material Particulado , Folhas de Planta , Ulmus , Folhas de Planta/microbiologia , Folhas de Planta/ultraestrutura , Ulmus/microbiologia , Microscopia Eletrônica de Varredura , Bactérias/classificação , Bactérias/genética , Biodiversidade
4.
BMC Plant Biol ; 24(1): 555, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877393

RESUMO

BACKGROUND: Selenium is essential for livestock and human health. The traditional way of adding selenium to livestock diets has limitations, and there is a growing trend to provide livestock with a safe and efficient source of selenium through selenium-enriched pasture. Therefore, this study was conducted to investigate the effects of selenium enrichment on fermentation characteristics, selenium content, selenium morphology, microbial community and in vitro digestion of silage alfalfa by using unenriched (CK) and selenium-enriched (Se) alfalfa as raw material for silage. RESULTS: In this study, selenium enrichment significantly increased crude protein, soluble carbohydrate, total selenium, and organic selenium contents of alfalfa silage fresh and post-silage samples, and it significantly decreased neutral detergent fiber and acid detergent fiber contents (p < 0.05). Selenium enrichment altered the form of selenium in plants, mainly in the form of SeMet and SeMeCys, which were significantly higher than that of CK (p < 0.05). Selenium enrichment could significantly increase the lactic acid content, reduce the pH value, change the diversity of bacterial community, promote the growth of beneficial bacteria such as Lactiplantibacillus and inhibit the growth of harmful bacteria such as Pantoea, so as to improve the fermentation quality of silage. The in vitro digestibility of dry matter (IVDMD), in vitro digestibility of acid detergent fibers (IVADFD) and in vitro digestibility of acid detergent fibers (IVNDFD) of silage after selenium enrichment were significantly higher than those of CK (p < 0.05). CONCLUSION: This study showed that the presence of selenium could regulate the structure of the alfalfa silage bacterial community and improve alfalfa silage fermentation quality. Selenium enrichment measures can change the morphology of selenium in alfalfa silage products, thus promoting the conversion of organic selenium.


Assuntos
Fermentação , Medicago sativa , Microbiota , Selênio , Silagem , Medicago sativa/metabolismo , Silagem/análise , Selênio/metabolismo , Animais , Ração Animal/análise
6.
ACS Biomater Sci Eng ; 10(6): 3935-3945, 2024 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-38741453

RESUMO

Achieving underwater adhesion possesses a significant challenge, primarily due to the presence of interfacial water, which restricts the potential applications of adhesives. In this study, we present a straightforward and environmentally friendly one-pot approach for synthesizing a solvent-free supramolecular TPFe bioadhesive composed of thioctic acid, proanthocyanidins, and FeCl3. The bioadhesive exhibits excellent biocompatibility and photothermal antibacterial properties and demonstrates effective adhesion on various substrates in both wet and dry environments. Importantly, the adhesive strength of this bioadhesive on steel exceeds 1.2 MPa and that on porcine skin exceeds 100 kPa, which is greater than the adhesive strength of most reported bioadhesives. In addition, the bioadhesive exhibits the ability to effectively halt bleeding, close wounds promptly, and promote wound healing in the rat skin wound model. Therefore, the TPFe bioadhesive has potential as a medical bioadhesive for halting bleeding quickly and promoting wound healing in the biomedical field. This study provides a new idea for the development of bioadhesives with firm wet adhesion.


Assuntos
Cicatrização , Animais , Cicatrização/efeitos dos fármacos , Ratos , Suínos , Adesivos Teciduais/química , Adesivos Teciduais/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Ratos Sprague-Dawley , Adesivos/química , Adesivos/farmacologia , Pele/efeitos dos fármacos , Pele/lesões , Pele/patologia , Técnicas de Fechamento de Ferimentos
7.
Polymers (Basel) ; 16(10)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38794508

RESUMO

Bacterial infections have a serious impact on public health. It is urgent to develop antibacterial hydrogels with good biocompatibility to reduce the use of antibiotics. In this study, poly(lipoic acid-co-sodium lipoate)-phytic acid (P(LA-SL)-PA) hydrogels are prepared by a simple mixture of the natural small molecules lipoic acid (LA) and phytic acid (PA) in a mild and green reaction environment. The crosslinking network is constructed through the connection of covalent disulfide bonds as well as the hydrogen bonds, which endow the injectable and self-healing properties. The P(LA-SL)-PA hydrogels exhibit an adjustable compression modulus and adhesion. The in vitro agar plates assay indicates that the antibacterial rate of hydrogels against Escherichia coli and Staphylococcus aureus is close to 95%. In the rat-infected wound model, the P(LA-SL)-PA hydrogels adhere closely to the tissue and promote epithelialization and collagen deposition with a significant effect on wound healing. These results prove that the P(LA-SL)-PA hydrogels could act as effective wound dressings for promoting the healing of infected wounds.

8.
Int J Biol Macromol ; 268(Pt 2): 131637, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38636748

RESUMO

Bacterial-infected wound repair has become a significant public health concern. This study developed a novel 3D-printed piezocatalytic SF-MA/PEGDA/Ag@BT (SPAB) hydrogels were fabricated by using digital light processing. These hydrogels exhibited high consistency, mechanical properties and good biocompatibility. Besides, the SPAB hydrogels exhibited excellent piezocatalytic performance and thus could induce piezoelectric polarization under ultrasound to generate reactive oxygen species (ROS). The SPAB hydrogels possessed an antibacterial rate of 99.23% and 99.96% for Escherichia coli and Staphylococcus aureus, respectively, under 5 min of ultrasonic stimulation (US) in vitro. The US-triggered piezocatalytic performance could increase antibacterial activity and improve the healing process of the infected wound. Therefore, the 3D printed piezocatalytic SPAB hydrogels could be unutilized as wound dressing in the field of bacterial-infected wound repair.


Assuntos
Antibacterianos , Escherichia coli , Hidrogéis , Impressão Tridimensional , Staphylococcus aureus , Cicatrização , Hidrogéis/química , Hidrogéis/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia , Catálise , Animais , Espécies Reativas de Oxigênio/metabolismo , Humanos , Polietilenoglicóis/química , Ondas Ultrassônicas
9.
J Hazard Mater ; 470: 134148, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38565012

RESUMO

There is increasing global concern regarding the pervasive issue of plastic pollution. We investigated the response of Populus × euramericana cv. '74/76' to nanoplastic toxicity via phenotypic, microanatomical, physiological, transcriptomic, and metabolomic approaches. Polystyrene nanoplastics (PS-NPs) were distributed throughout the test plants after the application of PS-NPs. Nanoplastics principally accumulated in the roots; minimal fractions were translocated to the leaves. In leaves, however, PS-NPs easily penetrated membranes and became concentrated in chloroplasts, causing thylakoid disintegration and chlorophyll degradation. Finally, oxidant damage from the influx of PS-NPs led to diminished photosynthesis, stunted growth, and etiolation and/or wilting. By integrating dual-omics data, we found that plants could counteract mild PS-NP-induced oxidative stress through the antioxidant enzyme system without initiating secondary metabolic defense mechanisms. In contrast, severe PS-NP treatments promoted a shift in metabolic pattern from primary metabolism to secondary metabolic defense mechanisms, an effect that was particularly pronounced during the upregulation of flavonoid biosynthesis. Our findings provide a useful framework from which to further clarify the roles of key biochemical pathways in plant responses to nanoplastic toxicity. Our work also supports the development of effective strategies to mitigate the environmental risks of nanoplastics by biologically immobilizing them in contaminated lands.


Assuntos
Nanopartículas , Poliestirenos , Populus , Clorofila/metabolismo , Metabolômica , Multiômica , Nanopartículas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Poliestirenos/toxicidade , Populus/efeitos dos fármacos , Populus/genética , Populus/metabolismo
10.
Int J Biol Macromol ; 264(Pt 2): 130741, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460649

RESUMO

Treatment of diabetic wounds is a major clinical issue. Diabetic wound dressings have higher requirements for anti-oxidant, antibacterial and wound monitoring properties compared to conventional wound dressings. In this study, a novel tannic acid (TA)/quaternized carboxymethyl chitosan (QCMCS)/oxidized sodium alginate (OSA)@carbon quantum dots (CQD) (TA/QCMCS/OSA@CQD) hydrogels for promoting diabetic wound healing and real-time monitoring have been developed. The TA/QCMCS/OSA@CQD hydrogels exhibited excellent self-healing, antibacterial and antioxidant properties. Besides, these hydrogels possessed good biocompatibility and effective hemostasis in a mouse liver injury model and significantly facilitated the healing process in a diabetic wound model. In addition, these hydrogels can reliable and timely measure the diabetic wound pH information by collecting image signals of hydrogels to monitor the healing status. Therefore, the pH responsive TA/QCMCS/OSA@CQD hydrogels could be utilized as wound dressing for promoting diabetic wound healing and real-time monitoring.


Assuntos
Quitosana , Diabetes Mellitus , Polifenóis , Animais , Camundongos , Alginatos , Antibacterianos , Antioxidantes , Carbono , Modelos Animais de Doenças , Hidrogéis , Concentração de Íons de Hidrogênio
11.
Bioact Mater ; 34: 64-79, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38186961

RESUMO

Given post-operative aseptic loosening in orthopedic disease treatment, osteointegration occurs at the bone-implant interface as a holistic process, including immunoregulation (e.g., macrophage polarization), angiogenesis and osteogenesis in sequence. In order to achieve early rapid and satisfactory osseointegration, different nano-shaped (nanocone, nanopolyhedron and nanoflower abbr. NC, NP & NF) cerium oxide (CeO2-x) coatings, endowed with "nanozyme-like" activities for multiple free radical elimination and osteoimmunology regulation, were hydrothermally synthesized on titanium alloy (TC4). In vitro cell experiments showed that nano-CeO2-x coated TC4 not only induced polarization of RAW264.7 cells toward M2 phenotype, but also promoted angiogenesis and vascularization of endothelial cells along with differentiation and mineralization of osteogenic precursor cells. Improvements in M2-polarized macrophage, angiogenesis, and bone regeneration were further confirmed in a rat femoral condyle model. Among the above three nano-morphologies, NF exhibited the best osseoinetegration. RNA sequencing and mechanism exploration suggested that the inhibition of PI3K-AKT signaling pathway was essential for immunomodulatory capacity of NF. In conclusion, it provided promising insights into the immunomodulatory exploitation of orthopedic implants.

12.
Carbohydr Polym ; 329: 121795, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38286559

RESUMO

Triple-negative breast cancer (TNBC) poses a serious threat to women's life and health due to its high malignancy, strong invasiveness, and propensity for early recurrence and metastasis. Therefore, there is an urgent need to develop a highly effective and low-toxic TNBC treatment scheme to enhance the anti-cancer efficacy and prolong the survival of patients. In this work, we designed and synthesized a chemodynamic therapy (CDT) agent (HA-Fc-Mal). The chemo/chemodynamic (CT/CDT) nanoparticle (HCM@DOX) based on hyaluronic acid induces ferroptosis and apoptotic for TNBC therapy was constructed via self-assembled of HA-Fc-Mal and doxorubicin (DOX). HCM@DOX orderly realized the TNBC targeting, controlled DOX release, GSH depletion and induce ROS erupt. In vivo and in vitro experiments confirmed that HCM@DOX inhibited the growth of 4 T1 tumors through ferroptosis and apoptosis, and the tumor inhibition rate was as high as 81.87 %. In addition, HCM@DOX significantly inhibited lung metastasis and exhibited excellent biosafety. Overall, our findings offer a new strategy for TNBC therapy using a CT/CDT nanoparticle that induces ferroptosis and apoptosis.


Assuntos
Ferroptose , Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Ácido Hialurônico/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Apoptose , Linhagem Celular Tumoral
13.
Int J Biol Macromol ; 257(Pt 2): 128611, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38070811

RESUMO

The R2R3-MYB gene family play an important role in plant growth, development and stress responses. In this study, a total of 122 PcoR2R3-MYB genes were identified and grouped into 26 clades in pear. And these PcoMYBs were unevenly distributed among 17 chromosomes. The sequence characteristics, conversed motifs, exon/intron structures, classification, duplication events and cis-acting elements were also investigated. The gene duplication events showed that segmental duplication may play key roles in expansion of the PcoMYB gene family. Pyrus hopeiensis, which is a valuable wild resource, has strong cold resistance. An integrative analyses of miRNA and mRNA showed that PhMYB62 was involved in regulating low-temperature stress in P. hopeiensis flower organs. Subcellular localization analysis showed that PhMYB62 protein was specifically localized to the nucleus. The result of DAP-seq showed that PhMYB62 responded to low-temperature stress in P. hopeiensis by regulating TFs, which were associated with plant stress resistance, and POD, GAUT12, AUX28 and CHS genes. Subsequently, yeast one-hybrid verified that PhMYB62 could bind and activate the promoter of POD gene. The current study would provide a comprehensive information for further functional research on the stress-responsive R2R3-MYB gene candidates in pear, and may help to identify the genes associated with cold resistance for the cultivation of cold-resistant pear varieties.


Assuntos
Pyrus , Pyrus/genética , Pyrus/metabolismo , Genoma de Planta , Genes myb , Fatores de Transcrição/metabolismo , Temperatura , Família Multigênica , Flores/genética , Filogenia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/química
14.
J Ethnopharmacol ; 319(Pt 3): 117346, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37879506

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Cryptotanshinone is the main bioactive component of Salvia miltiorrhiza, with various mechanisms of action, including antioxidant, anti-inflammatory, cardiovascular protection, neuroprotection, and hepatoprotection. Salvia miltiorrhiza is used clinically by gynecologists in China. AIM OF THE STUDY: Polycystic ovary syndrome (PCOS) has a significant impact on women's quality of life, leading to infertility and reproductive disorders. Hence, this study aims to assess the pharmacological activity of cryptotanshinone in the treatment of PCOS and investigate its therapeutic mechanism. MATERIALS AND METHODS: Human chorionic gonadotropin (HCG) combined with insulin is used to simulate a PCOS-like rat model and attempt to discover the abnormal changes that occur and the means by which the pathway acts in this model. RESULTS: The transcriptome sequencing method is used to identify 292 differential genes that undergo significant changes, of which 219 were upregulated and 73 were downregulated. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of the signaling pathways reveals that differential expressed genes are significantly enriched in 23 typical pathways. Estrogen signaling pathways are screened in the cryptotanshinone and model groups, and significant differential changes in Fos, ALOX12, and AQP8 are found. This suggests that these signaling pathways and molecules may be the main signaling targets for regulating the differences in endometrial tissue. CONCLUSION: These results indicate that cryptotanshinone has targets for regulating the proliferation of endometrial tissue via estrogen signaling pathways in PCOS-like rats, providing an experimental basis for the clinical application of cryptotanshinone in the treatment of PCOS.


Assuntos
Síndrome do Ovário Policístico , Feminino , Ratos , Humanos , Animais , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/metabolismo , Qualidade de Vida , Endométrio/metabolismo , Estrogênios/metabolismo
15.
Adv Healthc Mater ; 13(7): e2302901, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38102773

RESUMO

Bone metastases severely threaten the lives of patients. Although surgical treatment combined with adjuvant chemotherapy significantly improves the survival rate of patients, tumor recurrence, or metastasis after surgical resection and bone defects caused by surgical treatment remain major challenges for clinicians. Given the abovementioned clinical requirements, barium titanate-containing iron-coated porous titanium alloy scaffolds have been proposed to promote bone defect repair and inhibit tumor recurrence. Fortunately, in vitro and in vivo experimental research confirms that barium titanate containing iron-coated porous titanium alloy scaffolds promote osteogenesis and bone reconstruction in defect repair via mechanoelectric conversion and inhibit tumor recurrence via photothermal effects. Furthermore, the underlying and intricate mechanisms of bone defect repair and tumor recurrence prevention of barium titanate-containing iron-coated porous titanium alloy scaffolds are explored. A win-win strategy for mechanoelectrical conversion and photothermal functionalization provides promising insights into bone reconstruction of tumor-resected defects.


Assuntos
Alicerces Teciduais , Titânio , Humanos , Titânio/farmacologia , Porosidade , Bário , Recidiva Local de Neoplasia , Osteogênese , Ligas , Ferro
16.
Front Plant Sci ; 14: 1278715, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023849

RESUMO

Objective: This study aimed to analyze the fermentation quality, microbial community, and volatile metabolites of oat silage harvested at two different stages, while examining the correlation between microorganisms and volatile metabolites. Methods: Oats were harvested at two growth stages (pre-heading [PRH] and post-heading [POH] stages), followed by 90 days of natural fermentation, with 6 replicates per treatment. Pre- and post-silage samples were randomly selected for nutrient composition, fermentation parameters, microbial population, and high-throughput sequencing analysis. Volatile metabolomics analysis was also performed on samples after 90 days of fermentation to detect differences in flavor quality after silage. Results: The effect of growth stage on the nutrient content of oats was significant, with pre-heading oats having higher crude protein and post-heading oats having higher water soluble carbohydrates content (p < 0.05). Following a 90-day fermentation period, the pH and ammonia nitrogen/total nitrogen levels in the PRH-90 (silage from pre-heading oats after 90 days of fermentation) group demonstrated a significant decrease (p < 0.05), whereas the lactic acid content was notably higher compared to the POH-90 (silage from post-heading oats after 90 days of fermentation) group (p <0.05). Lactiplantibacillus dominated in the PRH-90 group and Enterococcus dominated in the POH-90 group, with abundances of (> 86%) and (> 87%), respectively. The differential volatile metabolites of the two treatment groups were dominated by esters and terpenoids, and the differences in flavor were mainly concentrated in sweet, green, and fruity odors. The results of Kyoto encyclopedia of genes and genomes pathway enrichment analysis demonstrated three major metabolic pathways: phenylpropanoid biosynthesis, phenylalanine metabolism, and biosynthesis of secondary metabolites. Specific microorganisms were significantly correlated with flavor indicators and flavor metabolites. Lactiplantibacillus was significantly positively correlated with flavor substances indicating sweet and fruity flavors, contributing to good flavor, while Enterococcus was significantly and positively correlated with flavor substances indicating bad flavors. Conclusion: In summary, growth stage had significant effects on nutritional components, fermentation parameters and flavor quality of oats, with the fermentation process dominated by Lactiplantibacillus leading to good flavor, while the fermentation process dominated by Enterococcus led to the development of poor flavor.

17.
Opt Lett ; 48(13): 3407-3410, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37390142

RESUMO

Acoustic splitters and electromagnetic splitters can be applied in various fields (e.g., navigation and interference detection). However, there is still a lack of study of structures that can simultaneously split acoustic and electromagnetic beams. In this study, a novel, to the best of our knowledge, electromagnetic-acoustic splitter (EAS) based on copper plates is proposed, which can simultaneously produce identical beam-splitting effects for transverse magnetic (TM)-polarized electromagnetic and acoustic waves. Different from previous beam splitters, the beam splitting ratio of the proposed passive EAS can be simply tuned by changing the incident angle of the input beam, i.e., a tunable splitting ratio can be achieved without additional energy consumption. The simulated results verify that the proposed EAS can create two transmitted split beams with a tunable splitting ratio for both electromagnetic and acoustic waves. This may have applications in dual-field navigation/detection, which can provide additional information and higher accuracy compared with single-field navigation/detection.


Assuntos
Acústica , Cobre , Som , Fenômenos Eletromagnéticos
18.
Adv Mater ; 35(29): e2210981, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37060549

RESUMO

Remote temperature control can be obtained by a long-focus thermal lens that can focus heat fluxes into a spot far from the back surface of the lens and create a virtual thermal source/sink in the background material, around which the temperature field distribution can be remotely controlled by varying the parameters of the thermal lens. However, because of the lack of negative thermal conductivity, existing thermal lenses have extremely short focal lengths and cannot be used to remotely control the temperature field around the virtual thermal source/sink. In this study, a general approach is proposed to equivalently realize materials with negative thermal conductivity using elaborately distributed active thermal metasurfaces (ATMSs). Subsequently, the proposed ATMS is used to implement a novel thermal lens with a long focal length designed using transformation thermodynamics, and finally realize the ATMS with realistic materials and experimentally verify the performance of the designed long-focus thermal lens (measured focal length of 19.8 mm) for remote heating/cooling. The proposed method expands the scope of the thermal conductivity and provides new pathways to realize unprecedented thermal effects with effective negative thermal conductivity, such as "thermal surface plasmon polaritons," a thermal superlens, the thermal tunneling effect, and the thermal invisible gateway.

19.
J Biomed Mater Res B Appl Biomater ; 111(7): 1398-1406, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36883804

RESUMO

A novel 3D-printed biodegradable cage composed of polycaprolactone (PCL) and beta-tricalcium phosphate (ß-TCP) in a mass ratio of 50:50, with stable resorption patterns and mechanical strength has been developed for lumbar interbody fusion. This is a prospective cohort study to evaluate the short- and mid-term safety and efficacy of this biodegradable cage in posterior lumbar interbody fusion (PLIF) surgery. This was a prospective single-arm pilot clinical trial in 22 patients with a follow-up time of 1, 3, 6, and 12 months, postoperatively. Clinical outcomes were assessed using the Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ) and Visual analogue scale (VAS) for leg pain and low back pain. Radiological examination included X-ray, CT scan, and three-dimensional reconstruction to evaluate surgical indications, intervertebral space height (ISH), intervertebral bone fusion and cage degradation. A total of 22 patients was included, with an average age of 53.5 years. Among 22 patients, one patient lost to follow-up and one patient withdrew from the clinical trial because of cage retropulsion. The remaining 20 patients showed significant improvement in clinical and imaging outcomes compared to the preoperative period. The overall mean VAS for back decreased from 5.85 ± 0.99 preoperatively to 1.15 ± 0.86 at the 12-month follow-up (p < .001); the VAS for leg decreased from 5.75 ± 1.11 to 1.05 ± 0.76 (p < .001); the JOA score improved from 13.8 ± 2.64 to 26.45 ± 2.46 (p < .001). The mean intervertebral space height (ISH) increased from 11.01 ± 1.75 mm preoperatively to 12.67 ± 1.89 mm at the 12-month follow-up and the bone fusion reached 95.2% (20/21 disc segments). Partial resorption (inferior to 50% compared with the initial cage size) were found in all cages (21/21). The clinical and radiological assessments showed that the application of 3D-printed biodegradable PCL/ß-TCP cages in PLIF yielded satisfactory results at the 12-month follow-up. In the future, long-term clinical observations and controlled clinical trials are required to further validate the safety and efficacy of this novel cage.


Assuntos
Vértebras Lombares , Fusão Vertebral , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Fusão Vertebral/métodos , Impressão Tridimensional , Resultado do Tratamento
20.
Microorganisms ; 11(2)2023 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-36838303

RESUMO

The aim of this study was to evaluate the effects of cellulase (CE) and lactic acid bacteria (LAB) on Caragana korshinskii silage by analyzing the fermentation parameters, chemical composition, and bacterial community. The Caragana korshinskii was harvested at the fruiting period and treated with cellulase and LAB alone as a control treatment with no additive (CK). The ensiling performance and bacterial community were determined after 3, 7, 15, 30, and 60 days of fermentation process. Compared with the CK group, the pH, dry matter loss, and ammonia nitrogen content were significantly (p < 0.05) decreased in the LAB and CE treatments. Compared with the CK and LAB group, the contents of acid detergent fiber, neutral detergent fiber, and acid detergent lignin in the CE group decreased significantly (p < 0.05), and the water-soluble carbohydrates, acetic acid, and lactic acid concentrations increased significantly (p < 0.05). At the genus level of microorganisms, the addition of cellulase and LAB significantly reduced the microbial diversity. Compared with the CK group (78.05%), the relative abundance of Lactiplantibacillus in the CE group (90.19%) and LAB group (88.40%) significantly (p < 0.05) increased. The relative abundance of Pediococcus in the CE group (3.66%) and LAB group (2.14%) was significantly (p < 0.05) lower than that in the CK group (14.73%). Predicted functional profiling of 16S rRNA genes revealed that the addition of cellulase and LAB increased the pyruvate metabolic pathway during Caragana korshinskii silage, thereby increasing the accumulation of lactic acid concentration. The addition of cellulase expressed a better advantage in the biosynthetic capacity of lysine. In summary, the addition of cellulase and LAB could adjust the bacterial community to improve the silage quality of Caragana korshinskii, and the addition of cellulase exhibited better results than the LAB additives.

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