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1.
J Neurochem ; 168(7): 1359-1373, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38382918

RESUMO

Ferroptosis has been implicated in several neurological disorders and may be therapeutically targeted. However, the susceptibility to ferroptosis varies in different cells, and inconsistent results have been reported even using the same cell line. Understanding the effects of key variables of in vitro studies on ferroptosis susceptibility is of critical importance to facilitate drug discoveries targeting ferroptosis. Here, we showed that increased cell seeding density leads to enhanced resistance to ferroptosis by reducing intracellular iron levels. We further identified iron-responsive protein 1 (IRP1) as the key protein affected by cell density, which affects the expression of ferroportin or transferrin receptor and results in altered iron levels. Such observations were consistent across different cell lines, indicating that cell density should be tightly controlled in studies of ferroptosis. Since cell densities vary in different brain regions, these results may also shed light on selective regional vulnerability observed in neurological disorders.


Assuntos
Ferroptose , Homeostase , Proteína 1 Reguladora do Ferro , Ferro , Ferro/metabolismo , Ferroptose/fisiologia , Homeostase/fisiologia , Humanos , Proteína 1 Reguladora do Ferro/metabolismo , Proteína 1 Reguladora do Ferro/genética , Contagem de Células , Animais , Receptores da Transferrina/metabolismo , Receptores da Transferrina/genética , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Transporte de Cátions/genética , Camundongos
2.
Opt Express ; 32(10): 17953-17965, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38858963

RESUMO

This article presents a dual-wavelength signal wave output system capable of generating a broad range of adjustable wavelength intervals. The setup involved the creation of a dual-wavelength cascaded Raman laser featuring composite cavities operating at 1176 nm and 1313 nm. Experimental investigations were carried out on an external cavity MgO:PPLN-OPO driven by the cascaded Raman laser. By setting the crystal polarization period to 27.6-34.4 µm and the temperature to 50-130°C, adjustable tunable output of dual-wavelength signal wave at 1176 nm-MgO:PPLN-OPO (1550-2294 nm) and 1313 nm-MgO:PPLN-OPO (1768-2189 nm) was achieved with a wavelength interval of 0-218 nm. Under the conditions of a period of 34.4 µm, temperature of 90°C, and an incident Raman power of 2.6 W, the highest conversion efficiency of Raman to dual-wavelength signal wave (2212, 2182 nm) was 34.2%. Furthermore, the maximum output power of dual-wavelength signal wave was recorded at 1.02 W with an incident Raman power of 3.33 W.

3.
Opt Lett ; 49(6): 1465-1468, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489426

RESUMO

The acousto-optic interaction known as stimulated Brillouin scattering (SBS) has emerged as a fundamental principle for realizing crucial components and functionalities in integrated photonics. However, the main challenge of integrating Brillouin devices is how to effectively confine both optical and acoustic waves. Apart from that, the manufacturing processes for these devices need to be compatible with standard fabrication platforms and streamlined to facilitate their large-scale integration. Here, we demonstrate a novel, to the best of our knowledge, suspended nanowire structure that can tightly confine photons and phonons. Furthermore, tailored for this structure, we introduce a loading-effect-based three-dimensional microfabrication technique, compatible with complementary metal-oxide-semiconductor (CMOS) technology. This innovative technique allows for the fabrication of the entire structure using a single-step lithography exposure, significantly streamlining the fabrication process. Leveraging this structure and fabrication scheme, we have achieved a Brillouin gain coefficient of 1100 W-1m-1 on the silicon-on-insulator platform within a compact footprint. It can support a Brillouin net gain over 4.1 dB with modest pump powers. We believe that this structure can significantly advance the development of SBS on chip, unlocking new opportunities for a large-scale integration of Brillouin-based photonic devices.

4.
Opt Lett ; 49(8): 2177-2180, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621105

RESUMO

Advancements in photonic integration technology have enabled the effective excitation of simulated Brillouin scattering (SBS) on a single chip, boosting Brillouin-based applications such as microwave photonic signal processing, narrow-linewidth lasers, and optical sensing. However, on-chip circuits still require large pump power and centimeter-scale waveguide length to achieve a considerable Brillouin gain, making them both power-inefficient and challenging for integration. Here, we exploit the slow-light effect to significantly enhance SBS, presenting the first, to the best of our knowledge, demonstration of a slow-light Brillouin-active waveguide on the silicon-on-insulator (SOI) platform. By integrating a Bragg grating with a suspended ridge waveguide, a 2.1-fold enhancement of the forward Brillouin gain coefficient is observed in a 1.25 mm device. Furthermore, this device shows a Brillouin gain coefficient of 1,693 m-1W-1 and a mechanical quality factor of 1,080. The short waveguide length reduces susceptibility to inhomogeneous broadening, enabling the simultaneous achievement of a high Brillouin gain coefficient and a high mechanical quality factor. This approach introduces an additional dimension to enhance acousto-optic interaction efficiency in the SOI platform and holds significant potential for microwave photonic filters and high spatial resolution sensing.

5.
Opt Lett ; 49(16): 4541-4544, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39146098

RESUMO

Stimulated Brillouin scattering (SBS) is a nonlinear optical phenomenon mediated from the coupling of photons and phonons. It has found applications in various realms, yet the acousto-optic interaction strength remains relatively weak. Enhancing the SBS with resonant structures could be a promising solution, but this method faces strict constraints in operational bandwidth. Here, we present the first demonstration to our knowledge of the broadband enhancement of Brillouin nonlinearities by a suspended coupled resonator optical waveguide (CROW) on an SOI platform. By comprehensively balancing the Brillouin gain and operational bandwidth, a 3-fold enhancement for the Brillouin gain coefficient (GB) and a broad operational bandwidth of over 80 GHz have been achieved. Furthermore, this 1.1 mm device shows a forward Brillouin gain coefficient of 2422 m-1W-1 and a high mechanical quality factor (Qm) of 1060. This approach marks a pivotal advancement toward wide bandwidth, low energy consumption, and compact integrated nonlinear photonic devices, with potential applications in tunable microwave photonic filters and phonon-based non-reciprocal devices.

6.
Langmuir ; 40(22): 11635-11641, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38775800

RESUMO

The presence of abnormal dopamine (DA) levels may cause serious neurological disorders, therefore, the quantitative analysis of DA and its related research are of great significance for ensuring health. Herein, the bovine serum albumin (BSA) template method has been proposed for the preparation of catalytically high-performance ruthenium dioxide/multiwalled carbon nanotube (RuO2/MWCNT) nanocomposites. The incorporation of MWCNTs has improved the active surface area and conductivity while effectively preventing the aggregation of RuO2 nanoparticles. The outstanding electrocatalytic performance of RuO2/MWCNTs has promoted the electro-oxidation of DA at neutral pH. The electrochemical sensing platform based on RuO2/MWCNTs has demonstrated a wide linear range (0.5 to 111.1 µM), low detection limit (0.167 µM), excellent selectivity, long-term stability, and good reproducibility for DA detection. The satisfactory recovery range of 94.7% to 103% exhibited by the proposed sensing podium in serum samples signifies its potential for analytical applications. The aforementioned results reveal that RuO2/MWCNT nanostructures hold promising aptitude in the electrochemical sensor to detect DA in real samples, further offering broad prospects in clinical and medical diagnosis.


Assuntos
Técnicas Biossensoriais , Dopamina , Técnicas Eletroquímicas , Nanotubos de Carbono , Compostos de Rutênio , Soroalbumina Bovina , Nanotubos de Carbono/química , Dopamina/sangue , Dopamina/análise , Dopamina/química , Humanos , Técnicas Biossensoriais/métodos , Soroalbumina Bovina/química , Técnicas Eletroquímicas/métodos , Compostos de Rutênio/química , Animais , Bovinos , Limite de Detecção
7.
Sensors (Basel) ; 24(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38676138

RESUMO

Soft sensors have been extensively utilized to approximate real-time power prediction in wind power generation, which is challenging to measure instantaneously. The short-term forecast of wind power aims at providing a reference for the dispatch of the intraday power grid. This study proposes a soft sensor model based on the Long Short-Term Memory (LSTM) network by combining data preprocessing with Variational Modal Decomposition (VMD) to improve wind power prediction accuracy. It does so by adopting the isolation forest algorithm for anomaly detection of the original wind power series and processing the missing data by multiple imputation. Based on the process data samples, VMD technology is used to achieve power data decomposition and noise reduction. The LSTM network is introduced to predict each modal component separately, and further sum reconstructs the prediction results of each component to complete the wind power prediction. From the experimental results, it can be seen that the LSTM network which uses an Adam optimizing algorithm has better convergence accuracy. The VMD method exhibited superior decomposition outcomes due to its inherent Wiener filter capabilities, which effectively mitigate noise and forestall modal aliasing. The Mean Absolute Percentage Error (MAPE) was reduced by 9.3508%, which indicates that the LSTM network combined with the VMD method has better prediction accuracy.

8.
Alzheimers Dement ; 20(6): 4185-4198, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38747519

RESUMO

INTRODUCTION: This study addresses the urgent need for non-invasive early-onset Alzheimer's disease (EOAD) prediction. Using optical coherence tomography angiography (OCTA), we present a choriocapillaris model sensitive to EOAD, correlating with serum biomarkers. METHODS: Eighty-four EOAD patients and 73 controls were assigned to swept-source OCTA (SS-OCTA) or the spectral domain OCTA (SD-OCTA) cohorts. Our hypothesis on choriocapillaris predictive potential in EOAD was tested and validated in these two cohorts. RESULTS: Both cohorts revealed diminished choriocapillaris signals, demonstrating the highest discriminatory capability (area under the receiver operating characteristic curve: SS-OCTA 0.913, SD-OCTA 0.991; P < 0.001). A sparser SS-OCTA choriocapillaris correlated with increased serum amyloid beta (Aß)42, Aß42/40, and phosphorylated tau (p-tau)181 levels (all P < 0.05). Apolipoprotein E status did not affect choriocapillaris measurement. DISCUSSION: The choriocapillaris, observed in both cohorts, proves sensitive to EOAD diagnosis, and correlates with serum Aß and p-tau181 levels, suggesting its potential as a diagnostic tool for identifying and tracking microvascular changes in EOAD. HIGHLIGHTS: Optical coherence tomography angiography may be applied for non-invasive screening of Alzheimer's disease (AD). Choriocapillaris demonstrates high sensitivity and specificity for early-onset AD diagnosis. Microvascular dynamics abnormalities are associated with AD.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Biomarcadores , Corioide , Tomografia de Coerência Óptica , Proteínas tau , Humanos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico por imagem , Feminino , Masculino , Peptídeos beta-Amiloides/sangue , Corioide/diagnóstico por imagem , Pessoa de Meia-Idade , Proteínas tau/sangue , Biomarcadores/sangue , Idoso , Fragmentos de Peptídeos/sangue , Estudos de Coortes
9.
Angew Chem Int Ed Engl ; 63(11): e202320036, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38191990

RESUMO

The striking aesthetic appeal of fullerene-like clusters has captured the interest of researchers. Nevertheless, the assembly of fullerene-like polyoxovadanadate (POV) cages remains a significant challenge due to the scarcity of suitable pentagonal motif. Herein, we have successfully synthesized the first fullerene-like all-inorganic POV cage, {(V2 O)V30 Nb12 O102 (H2 O)12 } (V30 Nb12 ), by introducing Nb into the POVs. V30 Nb12 is assembled by 12 heterometallic {(Nb)V5 } pentagons through sharing V centers with Ih symmetry, reminiscent of C60 . To our knowledge, the fullerene-like V30 Nb12 not only represents the highest-nuclearity POV cage but also stands as the first niobovanadate cluster. Notably, V30 Nb12 exhibits excellent solution stability, as confirmed by ESI-MS, FT-IR and UV/Vis spectra. As there is no protection organic ligand on its outer surface, V30 Nb12 can be further modified with Cu-complexes to form a fullerene-like cluster based zigzag chain (Cu-V30 Nb12 ).

10.
Front Psychol ; 15: 1345951, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737957

RESUMO

Introduction: While economics often interprets individual intertemporal choice preferences through the rationality assumption of utility maximization, the reality is that as emotional beings, individuals' preferences for intertemporal behavior are much more diverse and inconsistent. Prior research has predominantly focused on positive or negative emotions based on prospect theory, such as anxiety, anger, disgust, and depression. However, there has been relatively little research on how sadness affects individuals' preferences for immediate and future rewards. Methods: In this study, 170 college students are recruited as participants, and their emotions are primed with a video before engaging in an intertemporal task. Covariance analysis and logit regression model are established to examine the main and interactive effects of sadness on individuals' immediate reward preferences. Results: The findings reveal that sadness led individuals to prefer smaller immediate rewards, demonstrating a more myopic behavioral pattern, but didn't affect time discount rate. As the reward baseline increases, sadness's impact on immediate reward preferences is more pronounced, exacerbating individuals' myopic behavior. Discussion: In conclusion, these findings underscore the importance of considering emotional states in economic decision-making models and suggest avenues for future research to explore the complex dynamics of emotions and intertemporal choices.

11.
Talanta ; 280: 126707, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39146870

RESUMO

Monitoring lysosomal dynamics in real-time, especially in vivo, poses significant challenges due to the complex and dynamic nature of cellular environments. It is extremely important to construct fluorescent probes with high stability for imaging lysosomes to minimize interference from other cellular components, in order to ensure prolonged imaging. A fluorescent probe (PDB) has been proposed for targeting lysosomes, which was less affected to changes in the cellular microenvironment (such as pH, viscosity and polarity). PDB can be easily prepared by 4'-piperazinoacetophenone and 2-(4-diethylamino)-2-hydroxybenzoyl) benzoicacid, containing a piperazine group for labeling and imaging lysosomes and the high pKa value (∼9.35) allowed PDB to efficiently track lysosomes. The emission wavelength of PDB in aqueous solution was 634 nm (λex = 572 nm, Фf = 0.11). The dynamic process of lysosome induced by starvation and rapamycin was successfully explored by fluorescence imaging. Compared with the commercially available Lyso-Tracker green, the high photostability fluorescent probe can ensure 3D high-fidelity tracking and resist photobleaching. Therefore, PDB, unaffected by the cell microenvironment, successfully achieved long-term tracking of lysosomal movement, even enabling imaging in tumor-bearing mice over 11 days. The strong fluorescence signal, high stability, and long-term tracking capability indicate that PDB has tremendous potential in monitoring biological processes.

12.
Nat Commun ; 15(1): 3877, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719846

RESUMO

Empowering independent control of optical and acoustic modes and enhancing the photon-phonon interaction, integrated photonics boosts the advancements of on-chip stimulated Brillouin scattering (SBS). However, achieving acoustic waveguides with low loss, tailorability, and easy fabrication remains a challenge. Here, inspired by the optical anti-resonance in hollow-core fibers and acoustic anti-resonance in cylindrical waveguides, we propose suspended anti-resonant acoustic waveguides (SARAWs) with superior confinement and high selectivity of acoustic modes, supporting both forward and backward SBS on chip. Furthermore, this structure streamlines the design and fabrication processes. Leveraging the advantages of SARAWs, we showcase a series of breakthroughs for SBS within a compact footprint on the silicon-on-insulator platform. For forward SBS, a centimeter-scale SARAW supports a large net gain exceeding 6.4 dB. For backward SBS, we observe an unprecedented Brillouin frequency shift of 27.6 GHz and a mechanical quality factor of up to 1960 in silicon waveguides. This paradigm of acoustic waveguide propels SBS into a new era, unlocking new opportunities in the fields of optomechanics, phononic circuits, and hybrid quantum systems.

13.
Talanta ; 275: 126141, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38677168

RESUMO

The crucial cellular activities for maintaining normal cell functions heavily rely on the polarity of the endoplasmic reticulum (ER). Understanding how the polarity shifts, particularly in the context of ER autophagy (ER-phagy), holds significant promise for advancing knowledge of disorders associated with ER stress. Herein, a polarity-sensitive fluorescent probe CDI was easily synthesized from the condensation reaction of coumarin and dicyanoisophorone. CDI was composed of coumarin as the electron-donating moiety (D), ethylene and phenyl ring as the π-conjugation bridge, and malononitrile as the electron-accepting moiety (A), forming a typical D-π-A molecular configuration that recognition in the near-infrared (NIR) region. The findings suggested that as the polarity increased, the fluorescence intensity of CDI decreased, and it was accompanied by a redshift of emission wavelength at the excitation wavelength of 524 nm, shifting from 641 nm to 721 nm. Significantly, CDI exhibited a notable ability to effectively target ER and enabled real-time monitoring of ER-phagy induced by starvation or drugs. Most importantly, alterations in polarity can be discerned through in vivo imaging in mice model of rheumatoid arthritis (RA). CDI has been proven effective in evaluating the therapeutic efficacy of drugs for RA. ER fluorescent probe CDI can be optically activated in lysosomes, providing a sensitive tool for studying ER-phagy in biology and diseases.


Assuntos
Artrite Reumatoide , Autofagia , Retículo Endoplasmático , Corantes Fluorescentes , Animais , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Retículo Endoplasmático/metabolismo , Autofagia/efeitos dos fármacos , Camundongos , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/patologia , Artrite Reumatoide/metabolismo , Imagem Óptica , Humanos , Cumarínicos/química , Cumarínicos/síntese química , Raios Infravermelhos
14.
Org Lett ; 26(11): 2309-2314, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38466078

RESUMO

2-Alkylpyridines are a privileged scaffold throughout the realm of organic synthesis and play a key role in natural products, pharmaceuticals, and agrochemicals. Herein, we report the first B-alkyl Suzuki cross-coupling of 2-pyridyl ammonium salts to access functionalized 2-alkylpyridines. The use of well-defined, operationally simple Pd-NHCs permits for an exceptionally broad scope of the challenging B-alkyl C-N cross-coupling with organoboranes containing ß-hydrogen, representing a novel method for the discovery of highly sought-after molecules for plant protection.

15.
Int J Biol Macromol ; 264(Pt 1): 130536, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432273

RESUMO

Tremella fuciformis polysaccharide (TFPS) is a natural mushroom mucopolysaccharide widely used in health foods, medical care, cosmetic and surgical materials. In this study, we developed an efficient strategy for the repeated batch production of highly bioactive TFPS from the agro-industrial residue cane molasses. Cane molasses contained 39.92 % sucrose (w/w), 6.36 % fructose and 3.53 % glucose, all of which could be utilized by T. fuciformis spores, whereas, the TFPS production efficiency only reached 0.74 g/L/d. Corn cobs proved to be the best immobilized carrier that could tightly absorb spores and significantly shorten the fermentation lag period. The average yield of TFPS in eight repeated batch culture was 5.52 g/L with a production efficiency of 2.04 g/L/d. The average fermentation cycle after optimization was reduced by 61.61 % compared with the initial conditions. Compared to glucose as a carbon source, cane molasses significantly increased the proportion of low-molecular-weight TFPS (TFPS-2) in total polysaccharides from 3.54 % to 17.25 % (w/w). Moreover, TFPS-2 exhibited potent antioxidant capacity against four free radicals (O2-, ABTS+, OH, and DPPH). In conclusion, this study lays the foundation for the efficient conversion of cane molasses and production of TFPS with high bioactivity.


Assuntos
Basidiomycota , Técnicas de Cultura Celular por Lotes , Melaço , Bengala , Polissacarídeos/farmacologia , Polissacarídeos/química , Fermentação , Glucose
16.
Sci Total Environ ; 912: 169600, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38151126

RESUMO

The coexistence of multi-component dissolved organic chemicals causes tremendous challenge in purifying petrochemical wastewater, and stepwise selective adsorption holds the most promise for enhanced treatments. This study is designed to enhance the removal of multiple dissolved organic chemicals by stepwise adsorption. Special attention is given to the selective removal mechanisms for the major pollutant N,N-dimethylformamide (DMF), the sensitive pollutant fluorescent dissolved organic matter (FDOM) and other components. The results indicated that the combination of coal activated carbon and aluminum silica gel produced a synergistic effect and broke the limitation of removing only certain pollutants. Combined removal rates of 80.5 % for the dissolved organic carbon and 86.7 % for the biotoxicity in petrochemical wastewater were obtained with the enhanced two-step adsorption. The adsorption performance of both adsorbents remained stable even after five cycles. The selective adsorption mechanism revealed that hydrophobic organics such as DMF was adsorbed by the macropores of coal activated carbon, while the FDOM was eliminated by π-π stacking, electrostatic interaction and hydrophobic interaction. The hydrophilic organics were removed by the mesopores of aluminum silica gel, the silica hydroxyl groups and hydrophilic interaction. This study provides a comprehensive understanding of the selective adsorption mechanism and enhanced stepwise removal of multiple pollutants in petrochemical wastewater, which will guide the deep treatment of complex wastewater.

17.
Microbiol Spectr ; 12(5): e0018624, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38511949

RESUMO

Inoculation with plant growth-promoting rhizobacteria (PGPR) strains has promoted plant growth and decreased nitrous oxide (N2O) emissions from agricultural soils simultaneously. However, limited PGPR strains can mitigate N2O emissions from agricultural soils, and the microbial ecological mechanisms underlying N2O mitigation after inoculation are poorly understood. In greenhouse pot experiments, the effects of inoculation with Stutzerimonas stutzeri NRCB010 and NRCB025 on tomato growth and N2O emissions were investigated in two vegetable agricultural soils with contrasting textures. Inoculation with NRCB010 and NRCB025 significantly promoted tomato growth in both soils. Moreover, inoculation with NRCB010 decreased the N2O emissions from the fine- and coarse-textured soils by 38.7% and 52.2%, respectively, and inoculation with NRCB025 decreased the N2O emissions from the coarse-textured soil by 76.6%. Inoculation with NRCB010 and NRCB025 decreased N2O emissions mainly by altering soil microbial community composition and the abundance of nitrogen-cycle functional genes. The N2O-mitigating effect might be partially explained by a decrease in the (amoA + amoB)/(nosZI + nosZII) and (nirS + nirK)/(nosZI + nosZII) ratios, respectively. Soil pH and organic matter were key variables that explain the variation in abundance of N-cycle functional genes and subsequent N2O emission. Moreover, the N2O-mitigating effect varied depending on soil textures and individual strain after inoculation. This study provides insights into developing biofertilizers with plant growth-promoting and N2O-mitigating effects. IMPORTANCE: Plant growth-promoting rhizobacteria (PGPR) have been applied to mitigate nitrous oxide (N2O) emissions from agricultural soils, but the microbial ecological mechanisms underlying N2O mitigation are poorly understood. That is why only limited PGPR strains can mitigate N2O emissions from agricultural soils. Therefore, it is of substantial significance to reveal soil ecological mechanisms of PGPR strains to achieve efficient and reliable N2O-mitigating effect after inoculation. Inoculation with Stutzerimonas stutzeri strains decreased N2O emissions from two soils with contrasting textures probably by altering soil microbial community composition and gene abundance involved in nitrification and denitrification. Our findings provide detailed insight into soil ecological mechanisms of PGPR strains to mitigate N2O emissions from vegetable agricultural soils.


Assuntos
Microbiota , Óxido Nitroso , Microbiologia do Solo , Solo , Solanum lycopersicum , Verduras , Óxido Nitroso/metabolismo , Solo/química , Verduras/microbiologia , Verduras/crescimento & desenvolvimento , Solanum lycopersicum/microbiologia , Solanum lycopersicum/crescimento & desenvolvimento , Pseudomonas stutzeri/metabolismo , Pseudomonas stutzeri/crescimento & desenvolvimento , Pseudomonas stutzeri/genética , Agricultura/métodos
18.
Am J Sports Med ; 52(7): 1707-1718, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38702986

RESUMO

BACKGROUND: The tendon-bone interface (TBI) in the rotator cuff has a poor intrinsic capacity for healing, which increases the risk of retear after rotator cuff repair (RCR). However, facilitating regeneration of the TBI still remains a great clinical challenge. Herein, the authors established a novel strategy based on magnetic seeding to enhance the TBI regeneration. HYPOTHESIS: Magnetic seeding bone marrow mesenchymal stem cells labeled with superparamagnetic iron oxide (SPIO-BMSCs) into a biphasic scaffold can promote tendon-bone healing after RCR. STUDY DESIGN: Controlled laboratory study. METHODS: BMSCs were labeled with SPIOs. Prussian blue staining, CCK-8 tests, Western blot, and quantitative reverse transcription polymerase chain reaction (PCR) were used to determine the optimal effect concentration of SPIOs on cell bioactivities and abilities. Then SPIO-BMSCs were magnetically seeded into a biphasic scaffold under a magnetic field. The seeding efficacy was assessed by a scanning electron microscope, and the potential mechanism in chondrogenic differentiation after seeding SPIO-BMSCs into the scaffold was evaluated by Western blot and PCR. Furthermore, the effect of SPIO-BMSC/biphasic scaffold on tendon-bone healing after RCR using a rat model was examined using histological analysis, enzyme-linked immunosorbent assay, and biomechanical evaluation. RESULTS: BMSCs labeled with 100 µg/mL SPIO had no effect on cell bioactivities and the ability of chondrogenic differentiation. SPIO-BMSCs were magnetically seeded into a biphasic scaffold, which offered a high seeding efficacy to enhance chondrogenic differentiation of SPIO-BMSCs via the CDR1as/miR-7/FGF2 pathway for TBI formation in vitro. Furthermore, in vivo application of the biphasic scaffold with magnetically seeded SPIO-BMSCs showed their regenerative potential, indicating that they could significantly accelerate and promote TBI healing with superior biomechanical properties after RCR in a rat rotator cuff tear model. CONCLUSION: Magnetically seeding SPIO-BMSCs into a biphasic scaffold enhanced seeding efficacy to promote cell distribution and condensation. This construct enhanced the chondrogenesis process via the CDR1as/miR-7/FGF2 pathway and further promoted tendon-bone healing after RCR in a rat rotator cuff tear model. CLINICAL RELEVANCE: This study provides an alternative strategy for improving TBI healing after RCR.


Assuntos
Células-Tronco Mesenquimais , Ratos Sprague-Dawley , Lesões do Manguito Rotador , Alicerces Teciduais , Cicatrização , Animais , Lesões do Manguito Rotador/cirurgia , Lesões do Manguito Rotador/terapia , Células-Tronco Mesenquimais/fisiologia , Ratos , Masculino , Manguito Rotador/cirurgia , Transplante de Células-Tronco Mesenquimais , Nanopartículas Magnéticas de Óxido de Ferro , Diferenciação Celular , Condrogênese
19.
Pest Manag Sci ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877543

RESUMO

BACKGROUND: Cationic antimicrobial peptides (AMPs) possess broad-spectrum biological activities with less inclination to inducing antibiotic resistance. Herein a battery of amphiphilic amidines were designed by mimicking the characteristics of AMPs. The antifungal activities and the effects to the hyphal morphology and membrane permeability were investigated. RESULTS: The results indicated the inhibitory rates of ten compounds were over 80% to Botrytis cinerea and ten compounds over 90% to Valsa mali Miyabe et Yamada at 50 mg L-1. The half maximal effective concentration (EC50) values of compound 5g and 6g to V. mali were 1.21 and 1.90 mg L-1 respectively. The protective rate against apple canker of compound 5g reached 93.4% at 100 mg L-1 on twigs, superior to carbendazim (53.3%). When treated with 5g, the cell membrane permeability and leakage of content of V. mali increased, accompanied with the decrease of superoxide dismutase (SOD) and catalase (CAT) level. Concurrently, the mycelial hyphae contracted, wrinkled, and collapsed, providing evidence of membrane perturbation. A three-dimensional quantitative structure-activity relationship (3D-QSAR) between the topic compounds and the EC50 to V. mali was established showing good predictability (r2 = 0.971). CONCLUSION: Amphiphilic amidines can acquire antifungal activities by acting on the plasmic membrane. Compound 5g could be a promising lead in discovering novel fungicidal candidates. © 2024 Society of Chemical Industry.

20.
Sci Total Environ ; 917: 170395, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38307277

RESUMO

In the mangrove growth area, the availability of high-quality optical images is limited throughout the year due to cloud cover, precipitation, and sensor revisiting cycles. In the worst-case scenario, severe conditions may lead to the unavailability of, causing variations in monitoring times for mangroves across different years. This significantly impacts the accuracy of long-term sequence monitoring of mangrove dynamics. To monitor long-term dynamic changes in mangrove spatial distribution, area, and ecology we reconstructed comprehensive time series images from 2000 to 2020 based on Landsat, Sentinel-2, and moderate-resolution imaging spectroradiometer (MODIS) images. We employed neighborhood-similar pixel interpolator (NSPI) strip filling, Fmask and temporal NSPI cloud-removal and filling, and FSDAF model to monitor the long-term dynamic changes in mangrove spatial distribution, area, and ecology. All three methods effectively reconstructed the images, with the FSDAF model exhibiting the greatest accuracy. The reconstructed images suggested that the mangroves demonstrated an overall growth trend from 2000 to 2020, with an increase from 3796.74 ha to 7676.89 ha, an increase of approximately 3880.15 ha over 20 years. Despite this growth, the number of patches gradually increased, the degree of fragmentation consistently worsened, and the landscape shape gradually became irregular. The study area demonstrated pronounced overall heterogeneity, with a gradually increase in the degree of dispersion, indicating evident overall instability. Additionally, the centroid of the mangroves moved towards the ocean, which complicated their growth environment and posed a serious threat to their growth and recovery. Anthropogenic disturbance is the main factor driving changes in mangrove areas. Driving factors that affected the change in mangrove areas were ranked as follows: GDP > highway mileage > population density > precipitation > humidity > wind speed > sunshine > temperature. The results of this study provide comprehensive data for the protection and restoration of mangroves.

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