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1.
Front Bioeng Biotechnol ; 12: 1396892, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38720877

RESUMO

Hydrogel is considered as a promising candidate for wound dressing due to its tissue-like flexibility, good mechanical properties and biocompatibility. However, traditional hydrogel dressings often fail to fulfill satisfied mechanical, antibacterial, and biocompatibility properties simultaneously, due to the insufficient intrinsic bactericidal efficacy and the addition of external antimicrobial agents. In this paper, hydroxyl-contained acrylamide monomers, N-Methylolacrylamide (NMA) and N-[Tris (hydroxymethyl)methyl] acrylamide (THMA), are employed to prepare a series of polyacrylamide hydrogel dressings xNMA-yTHMA, where x and y represent the mass fractions of NMA and THMA in the hydrogels. We have elucidated that the abundance of hydroxyl groups determines the antibacterial effect of the hydrogels. Particularly, hydrogel 35NMA-5THMA exhibits excellent mechanical properties, with high tensile strength of 259 kPa and large tensile strain of 1737%. Furthermore, the hydrogel dressing 35NMA-5THMA demonstrates remarkable inherent antibacterial without exogenous antimicrobial agents owing to the existence of abundant hydroxyl groups. Besides, hydrogel dressing 35NMA-5THMA possesses excellent biocompatibility, in view of marginal cytotoxicity, low hemolysis ratio, and negligible inflammatory response and organ toxicity to mice during treatment. Encouragingly, hydrogel 35NMA-5THMA drastically promote the healing of bacteria-infected wound in mice. This study has revealed the importance of polyhydroxyl in the antibacterial efficiency of hydrogels and provided a simplified strategy to design wound healing dressings with translational potential.

2.
Polymers (Basel) ; 16(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38732663

RESUMO

The research used polyethersulfone (PES) as a membrane material, polyvinylpyrrolidone (PVP) k30 and polyethylene glycol 400 (PEG 400) as water-soluble additives, and dimethylacetamide (DMAc) as a solvent to prepare hollow-fiber ultrafiltration membranes through a nonsolvent-induced phase separation (NIPS) process. The hydrophilic nature of PVP-k30 and PEG caused them to accumulate on the membrane surface during phase separation. The morphology, chemical composition, surface charge, and pore size of the PES membranes were evaluated by SEM, FTIR, zeta potential, and dextran filtration experiments. The paper also investigated how different spinning solution compositions affected membrane morphology and performance. The separation efficiency of membranes with four different morphologies was tested in single-protein and double-protein mixed solutions. The protein separation effectiveness of the membrane was studied through molecular weight cutoff, zeta potential, and static protein adsorption tests. In addition, the operating pressure and pH value were adjusted to improve ultrafiltration process conditions. The PES membrane with an intact sponge-like structure showed the highest separation factor of 11, making it a prime candidate membrane for the separation of bovine serum albumin (BSA) and lysozyme (LYS). The membrane had a minimal static protein adsorption capacity of 48 mg/cm2 and had excellent anti-fouling properties. When pH = 4, the BSA retention rate was 93% and the LYS retention rate was 23%. Furthermore, it exhibited excellent stability over a pH range of 1-13, confirming its suitability for protein separation applications.

3.
J Am Chem Soc ; 146(19): 13499-13508, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38696816

RESUMO

Near-infrared (NIR) circularly polarized light absorbing or emitting holds great promise for highly sensitive and precise bioimaging, biosensing, and photodetectors. Aiming at designing NIR chiral molecular systems with amplified dissymmetry and robust chiroptical response, herein, we present a series of double π-helical dimers with longitudinally extended π-entwined substructures via Ullmann or Yamamoto homocoupling reactions. Circular dichroism (CD) spectra revealed an approximate linear bathochromic shift with the rising number of naphthalene subunits, indicating a red to NIR chiroptical response. Particularly, the terrylene diimide-entwined dimers exhibited the strongest CD intensities, with the maximal |Δε| reaching up to 393 M-1 cm-1 at 666 nm for th-TDI[2]; and a record-high chiroptical response (|ΔΔε|) between the neutral and dianionic species of 520 M-1 cm-1 at 833 nm for th-TDI[2]Cl was achieved upon further reduction to its dianionic state. Time-dependent density functional theory (TDDFT) calculations suggested that the pronounced intensification of the CD spectra originated from a simultaneous enhancement of both electric (µ) and magnetic (m) transition dipole moments, ultimately leading to an overall increase in the rotatory strength (R). Notably, the circularly polarized luminescence (CPL) brightness (BCPL) reached 77 M-1 cm-1 for th-TDI[2]Cl, among the highest values reported for NIR-CPL emitters. Furthermore, all chiral dianions exhibited excellent air stability under ambient conditions with half-life times of up to 10 days in N-methylpyrrolidone (NMP), which is significant for future biological applications and chiroptic switches.

4.
Transl Oncol ; 45: 101982, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38718436

RESUMO

Immune checkpoints inhibitors are effective but it needs more precise biomarkers for patient selection. We explored the biological significance of LINC00862 in pan-cancer by bioinformatics. And we studied its regulatory mechanisms using chromatin immunoprecipitation and RNA immunoprecipitation assays etc. TCGA and single-cell sequencing data analysis indicated that LINC00862 was overexpressed in the majority of tumor and stromal cells, which was related with poor prognosis. LINC00862 expression was related with immune cell infiltration and immune checkpoints expression, and had a high predictive value for immunotherapy efficacy. Mechanistically, LINC00862 competitively bound to miR-29c-3p to unleash SIRT1's tumor-promoting function. SIRT1 inhibitor-EX527 were screened by virtual screening and verified by in vitro and vivo assays. Notably, acetyltransferase P300-mediated super-enhancer activity stimulated LINC00862 transcription. Collectively, LINC00862 could be a diagnostic and prognostic biomarker. LINC00862 could also be a predictive biomarker for immunotherapy efficacy. Super-enhancer activity is the driver for LINC00862 overexpression in cervical cancer and gastric cancer.

5.
Bioact Mater ; 38: 31-44, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38699238

RESUMO

Rapid development of checkpoint inhibitors has provided significant breakthroughs for cancer stem cell (CSC) therapy, while the therapeutic efficacy is restricted by hypoxia-mediated tumor immune evasion, especially hypoxia-induced CD47 overexpression in CSCs. Herein, we developed a genetically engineered CSC membrane-coated hollow manganese dioxide (hMnO2@gCMs) to elicit robust antitumor immunity by blocking CD47 and alleviating hypoxia to ultimately achieve the eradication of CSCs. The hMnO2 core effectively alleviated tumor hypoxia by inducing decomposition of tumor endogenous H2O2, thus suppressing the CSCs and reducing the expression of CD47. Cooperating with hypoxia relief-induced downregulation of CD47, the overexpressed SIRPα on gCM shell efficiently blocked the CD47-SIRPα "don't eat me" pathway, synergistically eliciting robust antitumor-mediated immune responses. In a B16F10-CSC bearing melanoma mouse model, the hMnO2@gCMs showed an enhanced therapeutic effect in eradicating CSCs and inhibiting tumor growth. Our work presents a simple, safe, and robust platform for CSC eradication and cancer immunotherapy.

6.
Transplant Direct ; 10(6): e1623, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38757052

RESUMO

Background: Vascularized composite allograft transplantation is a treatment option for complex tissue injuries; however, ischemia reperfusion injury and high acute rejection rates remain a challenge. Hypothermic machine perfusion using acellular storage perfusate is a potential solution. This study evaluated the University of Wisconsin Kidney Preservation Solution-1 (KPS-1) compared with normal saline (NS) for preservation of donor rat hindlimbs subjected to 24 h of ex vivo perfusion cold storage. Methods: Hindlimbs were subjected to 24-h perfusion cold storage with heparinized KPS-1 (n = 6) or heparinized NS (n = 6). Flow, resistance, and pH were measured continuously. At the end of the 24-h period, tissue was collected for histological analysis of edema and apoptosis. Results: KPS-1 perfused limbs showed significantly less edema than the NS group, as evidenced by lower limb weight gain (P < 0.001) and less interfascicular space (P < 0.001). KPS-perfused muscle had significantly less cell death than NS-perfused muscle based on terminal deoxynucleotidyl transferase dUTP nick-end labeling (P < 0.001) and cleaved caspase-3 staining (P = 0.045). During hypothermic machine perfusion, a significant decrease in pH over time was detected in both groups, with a significantly greater decline in pH in the KPS-1 group than in the NS group. There were no significant differences overall and over time in flow rate or vascular resistance between the KPS and NS groups. Conclusions: Perfusion with KPS-1 can successfully extend vascularized composite allograft perfusion cold storage for 24 h in a rat hindlimb model without significant edema or cell death.

8.
Sci Total Environ ; 927: 172333, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38608896

RESUMO

Although ligand-promoted photodissolution of ferrihydrite (FH) has long been known for low molecular weight organic acids (LMWOAs), such as oxalate (Oxa) and malonate (Mal), photochemistry of coprecipitated FH with Oxa and Mal remains unknown, despite the importance of these mineral-organic associations in carbon retention has been acknowledged recently. In this study, ferrihydrite-LMWOAs associations (FLAs) were synthesized under circumneutral conditions. Photo-dissolution kinetics of FLAs were compared with those of adsorbed LMWOAs on FH surface and dissolved Fe-LMWOAs complexes through monitoring Fe(II) formation and organic carbon decay. For aqueous Fe(III)-LMWOAs complexes, Fe(II) yield was controlled by the initial concentration of LMWOAs and nature of photochemically generated carbon-centered radicals. Inner-sphere mononuclear bidentate (MB) configuration dominated while LMWOAs were adsorbed on the FH surface. MB complex of FH-Oxa was more photoreactive, leading to the rapid depletion of Oxa. Oxa can be readsorbed but in the form of binuclear bidentate and outer-sphere complexation, with much lower photoreactivity. While LMWOAs was coprecipitated with FH, the combination mode of LMWOAs with FH includes surface adsorption with a mononuclear bidentate structure and internal physical inclusion. Higher content of LMWOAs in the FLAs promoted the photo-production of Fe(II) as compared to pure FH, while it was not the case for FLAs containing moderate amounts of LMWOAs. The distinct photochemistry of adsorbed and coprecipitated Fe-LMWOAs complexes is attributed to ligand availability and configuration patterns of LMWOAs on the surface or entrapped in the interior structure. The present findings have significant implications for understanding the photochemical redox cycling of iron across the interface of Fe-organic mineral associates.

9.
iScience ; 27(4): 109553, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38623338

RESUMO

Electrocatalytic generation of H2O2 via the 2-electron pathway of oxygen reduction reaction (2e-ORR) is an attractive technology compared to the anthraquinone process due to convenience and environmental friendliness. However, catalysts with excellent selectivity and high activity for 2e-ORR are necessary for practical applications. Reported here is a catalyst comprising boron-doped porous carbon hollow spheres (B-PCHSs) prepared using the hard template method coupled with borate transesterification. In an alkali electrolyte, the selectivity of B-PCHS for 2e-ORR above 90% in range of 0.4-0.7 VRHE and an onset potential of 0.833 V was obtained. Meanwhile, the generation rate of H2O2 reached 902.48 mmol h-1 gcat-1 at 0.4 VRHE under 59.13 mA cm-2 in batch electrolysis. The excellent catalytic selectivity of B-PCHS for 2e-ORR originates from the boron element, and the catalytic activity of B-PCHS for H2O2 generation is contributed to the morphology of porous hollow spheres, which facilitates mass transfer processes.

10.
Int J Biol Macromol ; 268(Pt 1): 131833, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38663703

RESUMO

The emergence and widespread of multidrug-resistant Gram-negative bacteria have posed a severe threat to human health and environmental safety, escalating into a global medical crisis. Utilization of antibiotic adjuvants is a rapid approach to combat bacterial resistance effectively since the development of new antimicrobial agents is a formidable challenge. NhaA, driven by proton motive force, is a crucial secondary transporter on the cytoplasmic membrane of Escherichia coli. We found that 2-Aminoperimidine (2-AP), which is a specific inhibitor of NhaA, could enhance the activity of colistin against sensitive E. coli and reverse the resistance in mcr-1 positive E. coli. Mechanistic studies indicated that 2-AP induced dysfunction in cytoplasmic membrane through the suppression of NhaA, leading to metabolic inhibition and ultimately enhancing the sensitivity of E. coli to colistin. Moreover, 2-AP restored the efficacy of colistin against resistant E. coli in two animal infection models. Our findings reveal the potential of NhaA as a novel target for colistin adjuvants, providing new possibilities for the clinical application of colistin.


Assuntos
Colistina , Proteínas de Escherichia coli , Escherichia coli , Colistina/farmacologia , Escherichia coli/efeitos dos fármacos , Proteínas de Escherichia coli/metabolismo , Animais , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana/efeitos dos fármacos , Camundongos , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia
11.
Sci Total Environ ; 931: 172833, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38688369

RESUMO

Phthalates acid esters (PAEs) have accumulated in soil and crops like wheat as a result of the widespread usage of plastic films. It is yet unclear, nevertheless, how these dynamic variations in PAE accumulation in wheat tissues relate to rhizosphere bacteria in the field. In this work, a field root-bag experiment was conducted to examine the changes of PAEs accumulation in the rhizosphere soil and wheat tissues under film residue conditions at four different growth stages of wheat, and to clarify the roles played by the microbial community in the alterations. Results showed that the plastic film residues significantly increased the concentrations of PAEs in soils, wheat roots, straw and grains. The maximum ΣPAEs concentration in soils and different wheat tissues appeared at the maturity, with the ΣPAEs concentration of 1.57 mg kg-1, 4.77 mg kg-1, 5.21 mg kg-1, 1.81 mg kg-1 for rhizosphere soils, wheat roots, straw and grains, respectively. The plastic film residues significantly changed the functions and components of the bacterial community, increased the stochastic processes of the bacterial community assembly, and reduced the complexity and stability of the bacterial network. In addition, the present study identified some bacteria associated with plastic film residues and PAEs degradation in key-stone taxa, and their relative abundances were positive related to the ΣPAEs concentration in soils. The PAEs content and key-stone taxa in rhizosphere soil play a crucial role in the formation of rhizosphere soil bacterial communities. This field study provides valuable information for better understanding the role of microorganisms in the complex system consisting of film residue, soil and crops.


Assuntos
Ácidos Ftálicos , Rizosfera , Microbiologia do Solo , Poluentes do Solo , Triticum , Triticum/microbiologia , Poluentes do Solo/análise , Poluentes do Solo/metabolismo , Ácidos Ftálicos/metabolismo , Plásticos/metabolismo , Ésteres/análise , Ésteres/metabolismo , Bactérias/metabolismo , Solo/química , Microbiota , Raízes de Plantas/microbiologia , Raízes de Plantas/metabolismo
12.
ACS ES T Water ; 4(4): 1775-1785, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38633365

RESUMO

This study describes the development of the CHANnelized Optical System II (CHANOS II), an autonomous, in situ sensor capable of measuring seawater dissolved inorganic carbon (DIC) at high frequency (up to ∼1 Hz). In this sensor, CO2 from acidified seawater is dynamically equilibrated with a pH-sensitive indicator dye encapsulated in gas-permeable Teflon AF 2400 tubing. The pH in the CO2 equilibrated indicator is measured spectrophotometrically and can be quantitatively correlated to the sample DIC. Ground-truthed field data demonstrate the sensor's capabilities in both time-series measurements and surface mapping in two coastal sites across tidal cycles. CHANOS II achieved an accuracy and precision of ±5.9 and ±5.5 µmol kg-1. The mean difference between traditional bottle and sensor measurements was -3.7 ± 10.0 (1σ) µmol kg-1. The sensor can perform calibration in situ using Certified Reference Materials (CRMs) to ensure measurement quality. The coastal time-series measurements highlight high-frequency variability and episodic biogeochemical shifts that are difficult to capture by traditional methods. Surface DIC mapping shows multiple endmembers in an estuary and highlights fine-scale spatial variabilities of DIC. The development of CHANOS II demonstrates a significant technological advance in seawater CO2 system sensing, which enables high-resolution, subsurface time-series, and profiling deployments.

13.
Transl Vis Sci Technol ; 13(4): 28, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38648051

RESUMO

Purpose: Retinal and optic nerve diseases have become the primary cause of irreversible vision loss and blindness. However, there is still a lack of thorough evaluation regarding their prevalence in China. Methods: This artificial intelligence-based national screening study applied a previously developed deep learning algorithm, named the Retinal Artificial Intelligence Diagnosis System (RAIDS). De-identified personal medical records from January 2019 to December 2021 were extracted from 65 examination centers in 19 provinces of China. Crude prevalence and age-sex-adjusted prevalence were calculated by mapping to the standard population in the seventh national census. Results: In 2021, adjusted referral possible glaucoma (63.29, 95% confidence interval [CI] = 57.12-68.90 cases per 1000), epiretinal macular membrane (21.84, 95% CI = 15.64-29.22), age-related macular degeneration (13.93, 95% CI = 11.09-17.17), and diabetic retinopathy (11.33, 95% CI = 8.89-13.77) ranked the highest among 10 diseases. Female participants had significantly higher adjusted prevalence of pathologic myopia, yet a lower adjusted prevalence of diabetic retinopathy, referral possible glaucoma, and hypertensive retinopathy than male participants. From 2019 to 2021, the adjusted prevalence of retinal vein occlusion (0.99, 95% CI = 0.73-1.26 to 1.88, 95% CI = 1.42-2.44), macular hole (0.59, 95% CI = 0.41-0.82 to 1.12, 95% CI = 0.76-1.51), and hypertensive retinopathy (0.53, 95% CI = 0.40-0.67 to 0.77, 95% CI = 0.60-0.95) significantly increased. The prevalence of diabetic retinopathy in participants under 50 years old significant increased. Conclusions: Retinal and optic nerve diseases are an important public health concern in China. Further well-conceived epidemiological studies are required to validate the observed increased prevalence of diabetic retinopathy, hypertensive retinopathy, retinal vein occlusion, and macular hole nationwide. Translational Relevance: This artificial intelligence system can be a potential tool to monitor the prevalence of major retinal and optic nerve diseases over a wide geographic area.


Assuntos
Inteligência Artificial , Doenças do Nervo Óptico , Doenças Retinianas , Humanos , China/epidemiologia , Prevalência , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Doenças Retinianas/epidemiologia , Doenças Retinianas/diagnóstico , Doenças do Nervo Óptico/epidemiologia , Doenças do Nervo Óptico/diagnóstico , Adulto Jovem , Adolescente , Programas de Rastreamento/métodos , Idoso de 80 Anos ou mais
14.
Materials (Basel) ; 17(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38673105

RESUMO

Electrosynthesis of H2O2 via both pathways of anodic two-electron water oxidation reaction (2e-WOR) and cathodic two-electron oxygen reduction reaction (2e-ORR) in a diaphragm-free bath can not only improve the generation rate and Faraday efficiency (FE), but also simplify the structure of the electrolysis bath and reduce the energy consumption. The factors that may affect the efficiency of H2O2 generation in coupled electrolytic systems have been systematically investigated. A piece of fluorine-doped tin oxide (FTO) electrode was used as the anode, and in this study, its catalytic performance for 2e-WOR in Na2CO3/NaHCO3 and NaOH solutions was compared. Based on kinetic views, the generation rate of H2O2 via 2e-WOR, the self-decomposition, and the oxidative decomposition rate of the generated H2O2 during electrolysis in carbonate electrolytes were investigated. Furthermore, by choosing polyethylene oxide-modified carbon nanotubes (PEO-CNTs) as the catalyst for 2e-ORR and using its loaded electrode as the cathode, the coupled electrolytic systems for H2O2 generation were set up in a diaphragm bath and in a diaphragm-free bath. It was found that the generated H2O2 in the electrolyte diffuses and causes oxidative decomposition on the anode, which is the main influent factor on the accumulated concentration in H2O2 in a diaphragm-free bath.

15.
BMC Surg ; 24(1): 103, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600472

RESUMO

BACKGROUND: There is no effective consensus on the choice of internal fixation method for the Masquelet technique in the treatment of large segmental bone defects of the distal tibia. Thus, the study aimed to investigate the outcomes of the Masquelet technique combined with double plate fixation in the treatment of large segmental bone defects. METHODS: This was a retrospective study involving 21 patients with large segmental bone defects of the distal tibia who were treated between June 2017 and June 2020. The length of bone defect ranged from 6.0 cm to 11 cm (mean, 8.19 cm). In the first stage of treatment, following complete debridement, a cement spacer was placed to induce membrane formation. In the second stage, double plate fixation and autologous cancellous bone grafting were employed for bone reconstruction. Each patient's full weight-bearing time, bone healing time, and Iowa ankle score were recorded, and the occurrence of any complications was noted. RESULTS: All patients were followed up for 16 to 26 months (mean, 19.48 months). The group mean full weight-bearing time and bone healing time after bone grafting were 2.41 (± 0.37) months and 6.29 (± 0.66) months, respectively. During the treatment, one patient had a wound infection on the medial side of the leg, so the medial plate was removed. The wound completely healed after debridement without any recurrence. After extraction of iliac bone for grafting, one patient had a severe iliac bone defect, which was managed by filling the gap with a cement spacer. Most patients reported mild pain in the left bone extraction area after surgery. The postoperative Iowa ankle score range was 84-94 (P < 0.05). In this cohort, 15 cases were rated as "excellent", and 6 cases as "good" on the Iowa ankle scoring system. CONCLUSION: The Masquelet technique combined with double plate fixation is a safe and effective method for the treatment of large segmental bone defects of the distal tibia.


Assuntos
Procedimentos de Cirurgia Plástica , Fraturas da Tíbia , Humanos , Tíbia/cirurgia , Estudos Retrospectivos , Extremidade Inferior/cirurgia , Fixação Interna de Fraturas , Transplante Ósseo/métodos , Resultado do Tratamento , Fraturas da Tíbia/cirurgia
16.
Nano Lett ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38683656

RESUMO

The efficient cytosolic delivery of the CRISPR-Cas9 machinery remains a challenge for genome editing. Herein, we performed ligand screening and identified a guanidinobenzol-rich polymer to overcome the cascade delivery barriers of CRISPR-Cas9 ribonucleoproteins (RNPs) for genome editing. RNPs were stably loaded into the polymeric nanoparticles (PGBA NPs) by their inherent affinity. The polymer facilitated rapid endosomal escape of RNPs via a dynamic multiple-step cascade process. Importantly, the incorporation of fluorescence in the polymer helps to identify the correlation between cellular uptake and editing efficiency, increasing the efficiency up to 70% from the initial 30% for the enrichment of edited cells. The PGBA NPs efficiently deliver RNPs for in vivo gene editing via both local and systemic injections and dramatically reduce PCSK9 level. These results indicate that PGBA NPs enable the cascade delivery of RNPs for genome editing, showing great promise in broadening the therapeutic potential of the CRISPR-Cas9 technique.

17.
J Agric Food Chem ; 72(18): 10236-10246, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38647353

RESUMO

Arbuscular mycorrhizal (AM) fungi are essential for preserving the multifunctionality of ecosystems. The nitrogen (N)/phosphorus (P) threshold that causes notable variations in the AM fungus community of the soil and plant productivity is still unclear. Herein, a long-term (18 years) field experiment with five N and five P fertilizer levels was conducted to investigate the change patterns of soil AM fungus, multifunctionality, and wheat yield. High-N and -P fertilizer inputs did not considerably increase the wheat yield. In the AM fungal network, a statistically significant positive correlation was observed between ecosystem multifunctionality and the biodiversity of two primary ecological clusters (N: Module #0 and P: Module #3). Furthermore, fertilizer input thresholds for N (92-160 kg ha-1) and P (78-100 kg ha-1) significantly altered the AM fungal community, soil characteristics, and plant productivity. Our study provided a basis for reduced N and P fertilizer application and sustainable agricultural development from the aspect of soil AM fungi.


Assuntos
Fertilizantes , Micorrizas , Nitrogênio , Fósforo , Microbiologia do Solo , Solo , Triticum , Micorrizas/fisiologia , Fósforo/metabolismo , Triticum/microbiologia , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Nitrogênio/metabolismo , Fertilizantes/análise , Solo/química , Biodiversidade , Fazendas , Ecossistema
18.
Artigo em Inglês | MEDLINE | ID: mdl-38591200

RESUMO

BACKGROUND: In the domain of functional gastrointestinal disorders, Functional Dyspepsia (FD) stands out due to its widespread occurrence internationally. Historically, electroacupuncture (EA) has been employed as a therapeutic modality for FD, demonstrating notable clinical efficacy. OBJECTIVES: This research aimed to delve into the impact of EA on stress responses, minor duodenal inflammatory processes, and the integrity of the intestinal barrier within FD-affected rodent models while also elucidating the underlying mechanisms. METHODS: Thirty-six male Wistar rats were evenly distributed into three cohorts: a normal, a modeled FD, and an EA treatment group. The FD condition in the rats, barring those in the normal, was induced through a series of multifactorial procedures. For the EA cohort, the rats received electroacupuncture at the acupoints RN12 (Zhongwan) and ST36 (Zusanli) for 20 minutes daily over a span of one week. The gastric residue rate (GRR), intestinal propulsion rate (IPR), and changes in emotional state were measured in each group of rats. Additionally, serum levels of corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and corticosterone (CORT) were detected, and the duodenal inflammatory condition and intestinal mucosal barrier status were observed through staining and fluorescence. The expression levels of Claudin-1, Junctional Adhesion Molecule 1 (JAM-1), Corticotropin-Releasing Factor (CRF), and Corticotropin-Releasing Factor Receptor 1 (CRF-R1) were also detected. RESULTS: The study demonstrated that EA had a positive effect on body weight and food intake, GRR, and IPR in FD rats. Additionally, the EA group showed a decrease in serum levels of CRH, ACTH, and CORT, as well as a decrease in the number of duodenal mast cells and tryptase content. Furthermore, the expression of tight junction proteins Claudin-1 and JAM-1 was increased in the EA group compared to the model group. EA also reduced the levels of CRF and CRF-R1 in the hypothalamus and duodenum. CONCLUSION: EA has been shown to improve the stress state of FD rats, inhibit the activation of mast cells in the duodenum, and reduce low-grade inflammatory response and damage to the intestinal mucosal barrier. It is believed that EA achieves these effects by modulating the expression of CRF and its receptors in the brain-gut interaction pathway through the CRF signaling pathway. This provides a new approach to treating FD.

19.
Water Res ; 255: 121519, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38552488

RESUMO

Whilst it is generally recognized that phosphate enables to promote the removal of some organic pollutants with peroxymonosulfate (PMS) oxidation, however, there is an ongoing debate as to whether free radicals are involved. By integrating different methodologies, here we provide new insights into the reaction mechanism of the binary mixture of phosphates (i.e., NaH2PO4, Na2HPO3, and NaH2PO2) with peroxymonosulfate (PMS) or hydrogen peroxide (H2O2). Enhanced degradation of organic pollutants and observation of 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) adducts (i.e. DMPOOH and 5,5-dimethyl-2-oxopyrroline-1-oxyl (DMPOX)) with electron paramagnetic resonance (EPR) in most phosphates/PMS system seemly support a radical-dominant mechanism. However, fluorescence probe experiments confirm that no significant amount of hydroxyl radicals (•OH) are produced in such reaction systems. PMS in the phosphate solutions (without any organics) remains relatively stable, but is only consumed while organic substrates are present, which is distinct from a typical radical-dominant Co2+/PMS system where PMS is continuously decomposed. Through density functional theory (DFT) calculation, the energy barriers of the phosphates/PMS reaction processes are greatly decreased when non-radical mechanism dominates. Complementary evidence suggests that the reactive intermediates of PMS-phosphate complex, rather than the free radicals, are capable of oxidizing electron-rich substrates such as DMPO and organic pollutants. Taking the case of phosphate/PMS system as an example, this study demonstrates the necessity of acquisition of lines of evidence for resolving paradoxes in identifying EPR adducts.

20.
Angew Chem Int Ed Engl ; 63(19): e202319997, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38499464

RESUMO

High ambipolar mobility emissive conjugated polymers (HAME-CPs) are perfect candidates for organic optoelectronic devices, such as polymer light emitting transistors. However, due to intrinsic trade-off relationship between high ambipolar mobility and strong solid-state luminescence, the development of HAME-CPs suffers from high structural and synthetic complexity. Herein, a universal design principle and simple synthetic approach for HAME-CPs are developed. A series of simple non-fused polymers composed of charge transfer units, π bridges and emissive units are synthesized via a two-step microwave assisted C-H arylation and direct arylation polymerization protocol with high total yields up to 61 %. The synthetic protocol is verified valid among 7 monomers and 8 polymers. Most importantly, all 8 conjugated polymers have strong solid-state emission with high photoluminescence quantum yields up to 24 %. Furthermore, 4 polymers exhibit high ambipolar field effect mobility up to 10-2 cm2 V-1 s-1, and can be used in multifunctional optoelectronic devices. This work opens a new avenue for developing HAME-CPs by efficient synthesis and rational design.

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