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1.
Stress ; 27(1): 2374768, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38975691

RESUMO

Stress has been linked to the development of irritable bowel syndrome (IBS), and various methods have been explored to model IBS in combination with other stimuli. However, it remains unclear whether stress alone can induce IBS in animals. This study aimed to investigate the impact of chronic unpredictable mild stress (CUMS) on gastrointestinal sensation and function in mice and assess the potential of CUMS as a modeling approach for IBS. To evaluate the mice's behavior, we conducted open field test, sucrose preference test and weighed the mice, revealing that CUMS indeed induced anxiety and depression in the mice and caused weight loss. Further analyses, including fecal analysis, a total gastrointestinal transport test, and a colon propulsion test, demonstrated that CUMS led to abnormal defecation and disruptions in gastrointestinal motility in the mice. Additionally, the abdominal withdrawal reflex test indicated an increase in visceral sensitivity in CUMS-exposed mice. Histological examination using hematoxylin and eosin staining revealed no significant histological alterations in the colons of CUMS-exposed mice, but it did show a minor degree of inflammatory cell infiltration. In summary, the findings suggest that CUMS can replicate IBS-like symptoms in mice, offering a novel top-down approach to modeling IBS.


Assuntos
Modelos Animais de Doenças , Motilidade Gastrointestinal , Síndrome do Intestino Irritável , Estresse Psicológico , Animais , Estresse Psicológico/fisiopatologia , Estresse Psicológico/complicações , Masculino , Camundongos , Síndrome do Intestino Irritável/fisiopatologia , Motilidade Gastrointestinal/fisiologia , Ansiedade/fisiopatologia , Depressão/fisiopatologia , Camundongos Endogâmicos C57BL , Comportamento Animal , Defecação , Colo/fisiopatologia , Colo/patologia
2.
Int J Biol Macromol ; 257(Pt 1): 128648, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38061518

RESUMO

Interfacing cellulose nanocrystals (CNCs) with fluorescent materials provides more possibilities for constructing of sensory/imaging platforms in biomedical applications. In this work, by harnessing the efficient extraction accompanied modification of CNCs and adjustable optical properties of carbon dots (CDs), we report the constructions and emission wavelength tuning of fluorescent CNCs (F-CNCs) composed of CNC nano-scaffolds and CDs. The as-prepared CNCs are densely decorated with citric acid (CA), which plays the role of carbon source for the in-situ synthesis of CDs on CNCs. For the F-CNCs carrying blue, green, and red emissive CDs, ethylenediamine (EDA), urea, and thiourea are the N or N/S sources. Fingerprints of chemical groups, morphological characters, and redox activities are resolved to elaborate the optical mechanisms of CDs with varying emission colors. The emission wavelength is adjusted by either changing the particle size or introducing new emission centers. Both are primarily achieved via precursor engineering. The F-CNCs reveal quantum yields (QYs) >22 % and negligible fluorescence quenching (< 6 %) upon continuous excitation as long as 24 h. Benefited from their cell membrane penetration capability, the F-CNCs with different emission wavelengths were challenged for multiplexed cytoplasm imaging.


Assuntos
Nanopartículas , Pontos Quânticos , Pontos Quânticos/química , Corantes Fluorescentes/química , Celulose/química , Nanopartículas/química , Carbono/química
3.
Nanomaterials (Basel) ; 13(21)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37947715

RESUMO

Tuning the optical properties of carbon dots (CDs) and figuring out the mechanisms underneath the emissive phenomena have been one of the most cutting-edge topics in the development of carbon-based nanomaterials. Dual-emissive CDs possess the intrinsic dual-emission character upon single-wavelength excitation, which significantly benefits their multi-purpose applications. Explosive exploitations of dual-emissive CDs have been reported during the past five years. Nevertheless, there is a lack of a systematic summary of the rising star nanomaterial. In this review, we summarize the synthesis strategies and optical mechanisms of the dual-emissive CDs. The applications in the areas of biosensing, bioimaging, as well as photoelectronic devices are also outlined. The last section presents the main challenges and perspectives in further promoting the development of dual-emissive CDs. By covering the most vital publications, we anticipate that the review is of referential significance for researchers in the synthesis, characterization, and application of dual-emissive CDs.

4.
Appl Opt ; 62(24): 6350-6357, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37706825

RESUMO

Laser focusing is an important parameter that affects the characteristics of laser-induced plasma. Focusing lenses with different F-numbers form different energy density distributions near the surface of a sample, thus affecting the characteristics of plasma. In this study, the plasma generated by a nanosecond laser ablation of a micro-alloy steel certified sample at 1 atm of air was investigated. We compare the spectrally integrated plasma images obtained at different defocusing distances for short- and long-focus lenses and investigate the optical emission spectra of laser-induced plasma on steel alloy by using focusing lenses with different F-numbers. With an increase in the defocusing distance, the plasma plume changes from flat to hemispherical and then splitting occurs. The spectral line intensity increases first and then decreases, then increases slightly, and finally decreases gradually. For the long-focus lens, when the focal point is above the sample surface, the laser beam strongly interacts with air over a longer distance, leading to longer air plasma and weaker sample plasma compared with the short-focus lens. Thus, the relative intensity of the second peak in the spectral line intensity, according to the defocusing distance, gradually decreases with increasing F-number. We also obtain two-dimensional spatial distributions of the spectral line intensity according to the F-number and defocusing distance. The optimal defocusing distances for all focusing lenses occur when the focal point is below the sample surface. The relation between the optimal defocusing distance and F-number follows a single- exponential decay function.

5.
Brain Res Bull ; 201: 110700, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37414302

RESUMO

Electroacupuncture (EA) has been shown to enhance the recovery of symptoms in rheumatoid arthritis (RA); however, the underlying mechanism remains unclear. Both the pathogenesis of RA and the therapeutic effects of EA are closely associated with the metabolic activity of the brain. In this study, we investigated the effect of EA at the "Zusanli" acupoint (ST36) on a rat model of collagen-induced rheumatoid arthritis (CIA). The results demonstrated that EA effectively alleviated joint swelling, synovial hyperplasia, cartilage erosion, and bone destruction in CIA rats. Additionally, the metabolic kinetics study revealed a significant increase in the 13C enrichment of GABA2 and Glu4 in the midbrain of CIA rats treated with EA. Correlation network analysis showed that changes in Gln4 levels in the hippocampus were strongly associated with the severity of rheumatoid arthritis. Immunofluorescence staining of c-Fos in the midbrain's periaqueductal gray matter (PAG) and hippocampus demonstrated increased c-Fos expression in these regions following EA treatment. These findings suggest that GABAergic and glutamatergic neurons in the midbrain, along with astrocytes in the hippocampus, may play vital roles in the beneficial effects of EA on RA. Furthermore, the PAG and hippocampus brain regions hold potential as critical targets for future RA treatments. Overall, this study provides valuable insights into the specific mechanism of EA in treating RA by elucidating the perspective of cerebral metabolism.


Assuntos
Artrite Reumatoide , Eletroacupuntura , Ratos , Animais , Ratos Sprague-Dawley , Cinética , Artrite Reumatoide/terapia , Artrite Reumatoide/induzido quimicamente , Substância Cinzenta Periaquedutal
6.
CNS Neurosci Ther ; 29 Suppl 1: 31-42, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36585803

RESUMO

AIMS: Patients with acute liver injury (ALI) can develop cognitive dysfunction (CD). The study investigated the role of gut microbiota and cerebral metabolism in ALI mice with and without CD. METHODS: Male C57BL/6 mice that received thioacetamide were classified into ALI mice with (susceptible) or without (unsusceptible) CD-like phenotypes by hierarchical cluster analysis of behavior. The role of gut microbiota was investigated by 16S ribosomal RNA gene sequencing and feces microbiota transplantation (FMT). 1 H-[13 C] NMR and electrophysiology were used to detect the changes in cerebral neurotransmitter metabolic and synaptic transition in neurons or astrocytes. RESULTS: Apromixlay 55% (11/20) of mice developed CD and FMT from the susceptible group transmitted CD to gut microbiota-depleted mice. Alloprevotella was enriched in the susceptible group. GABA production was decreased in the frontal cortex, while hippocampal glutamine was increased in the susceptible group. Altered Escherichia. Shigella and Alloprevotella were correlated with behaviors and cerebral metabolic kinetics and identified as good predictors of ALI-induced CD. The frequencies of both miniature inhibitory and excitatory postsynaptic currents in hippocampal CA1 and prefrontal cortex were decreased in the susceptible group. CONCLUSION: Altered transmitter metabolism and synaptic transmission in the hippocampus and prefrontal cortex and gut microbiota disturbance may lead to ALI-induced CD.


Assuntos
Disfunção Cognitiva , Microbioma Gastrointestinal , Camundongos , Masculino , Animais , Microbioma Gastrointestinal/fisiologia , Camundongos Endogâmicos C57BL , Fígado , Transplante de Microbiota Fecal
7.
Heliyon ; 9(12): e22645, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38213597

RESUMO

Objective: This study aimed to explore whether acupuncture and moxibustion can enhance the immune response by increasing the expression of the endogenous adjuvant HSP70 mRNA. Method: Forty Wistar rats were divided into four groups: model immune acupuncture group (A), model immune control group (B), normal immune acupuncture group (C), and normal immune control group (D). Model immune groups A and B were induced by injecting d-galactose for 6 weeks. Rats in groups A and C were then treated with low-frequency electroacupuncture (EA) at Zusanli (ST36), Guanyuan (CV4), and Baihui (GV20) and moxibustion for 3 weeks. Subsequently, all rats were observed for 2 more weeks. At the 12th week, diphtheria antitoxin titers were determined using the Vero cell trace neutralization method, CD4+T/CD8+T cell ratios in peripheral blood were examined by flow cytometry, and the relative expression of spleen cell HSP70 mRNA was measured by RT-PCR. Results: Compared with the normal immune control, the diphtheria antitoxin titer, CD4+T/CD8+T cell ratio, and expression of spleen cell HSP70 mRNA significantly decreased in the model immune control group (P < 0.01). However, the model immune acupuncture group showed a significant increase in antitoxin titer (P < 0.01) and elevated CD4+T/CD8+T cell ratio and HSP70 mRNA expression (P < 0.05) after EA and moxibustion intervention. Conclusion: Acupuncture and moxibustion may enhance the humoral immune response (diphtheria antitoxin titer) and cellular immune response (peripheral blood CD4+T/CD8+T cell ratio) by increasing the expression of the endogenous adjuvant HSP70 mRNA, suggesting that acupuncture may serve as a new vaccine adjuvant.

8.
Carbohydr Polym ; 298: 120073, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36241317

RESUMO

In this work, a versatile cellulose nanocrystal­carbon dots (CNC-CDs) architecture is prepared and applied in environmental remediation and biological sensing. The citric acid (CA) is employed to extract CNCs and in-situ synthesize blue-emissive CDs. The carboxyl-rich surface of CNC-CDs enables the chelation of Hg2+ and fluorescence quenching of CDs, realizing the detection and adsorption of Hg2+ with a film comprised of the architecture. The limit of detection (LOD) is measured as 12.8 nM with satisfying retention efficiency. The versatility of CNC-CDs is demonstrated by the fabrication of a fluorescence resonance energy transfer (FRET) sensor using m-tetrakis(4-sulfonatophenyl)porphine (TSPP) as FRET acceptor and Fe3+ receptor. Fluorescence of the sensor is responsive to Fe3+ in a ratiometric manner, which significantly contributes to the visualized and sensitive Fe3+ detection (6.9 nM). In combination with excellent biocompatibility, the FRET sensor is capable of imaging intracellular Fe3+.


Assuntos
Mercúrio , Nanopartículas , Pontos Quânticos , Carbono , Celulose , Ácido Cítrico , Corantes Fluorescentes
9.
Anal Bioanal Chem ; 414(26): 7741-7751, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36056266

RESUMO

Exploring sensors based on Förster resonance energy transfer (FRET) systems enables the continuous development of biological sensing technologies. Herein, we report the construction of a FRET sensor with dual-emissive quantum dots (QDs) and meso-tetra(4-sulfonatophenyl) porphine (TSPP). The sensor is composed of mesial green-emissive QDs with a thick silica shell (gQD@SiO2) and circumjacent blue-emissive QDs coated with ultra-thin silica spacer, on which is linked TSPP (bQD@SiO2-TSPP). The gQD@SiO2 endows the sensor with a fluorescent background. Due to the ultra-thin silica spacing, coupled with the superior resonance effect of bQD fluorescence and the Soret-band absorption of TSPP, the FRET efficiency is highly sensitive to the chelation state of TSPP. Relying on the absorbance transition of TSPP complexed with Fe(III), the FRET sensor is applied for ultra-sensitive Fe(III) detection. In aqueous solution, the sensor is demonstrated to linearly detect Fe(III) in the range of 0-1 µM, with a limit of detection (LOD) of 40 nM. More importantly, reliable Fe(III) detection can be achieved via the specific complexation of Fe(III) by TSPP and the ratiometric fluorescent response. As such, the inter-/intra-day precisions in standard samples, as well as the recovery rate in biological matrices, are fully validated. The excellent analytical performance, in combination with the excellent biocompatibility of the FRET sensor, allows semi-quantitative Fe(III) imaging in living cells.


Assuntos
Porfirinas , Pontos Quânticos , Transferência Ressonante de Energia de Fluorescência/métodos , Compostos Férricos , Dióxido de Silício
10.
Medicine (Baltimore) ; 101(29): e29218, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35866802

RESUMO

BACKGROUND: Irritable bowel syndrome (IBS) is a common functional bowel disorder. Many systematic reviews/meta-analyses indicate that acupuncture and related therapies are effective for IBS. However, the robustness of the results in the systematic reviews and meta-analyses has not been evaluated. This scoping review aims to ascertain the credibility of current evidence of acupuncture therapy for IBS, to provide clinical research investigators with reliable information. METHODS: Searches of China National Knowledge Infrastructure (CNKI), China Science and Technology Journal Database (VIP), China Biology Medicine disc (CBMdisc), and Wanfang Database since the establishment of the database to February 2022. Study selection and data extraction will be conducted by 2 reviewers, and the quality will be assessed by 2 trained reviewers. We will use Assessment of Multiple Systematic Reviews-2 (AMSTAR2) for methodological quality assessment, Preferred Reporting Items for Systematic Reviews and Meta-Analyses for report quality assessment, Grading of Recommendations, Assessment, Development, and Evaluation for the quality of evidence assessment, and the Risk of Bias in Systematic Reviews for the bias assessment. RESULTS: The results will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: INPLASY202210117. CONCLUSION: This scoping review will provide comprehensive evidence of acupuncture for patients with irritable bowel syndrome. ETHICS AND DISSEMINATION: This scoping review does not require ethical approval as it is a secondary assessment of available literature.


Assuntos
Terapia por Acupuntura , Síndrome do Intestino Irritável , Terapia por Acupuntura/métodos , China , Gerenciamento de Dados , Bases de Dados Factuais , Humanos , Síndrome do Intestino Irritável/terapia , Projetos de Pesquisa , Literatura de Revisão como Assunto , Revisões Sistemáticas como Assunto
11.
Biosens Bioelectron ; 197: 113781, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34781178

RESUMO

Demand on the quick screening of gastric cancer (GC) has significantly stimulated the development of biomarker sensing techniques. Herein, we report the novel fluorescent paper-based analytical devices (PADs) for detections of GC-related microRNA-21 (miRNA-21) and circular RNA from Hippocampus Abundant Transcript 1 gene (circRNA-HIAT1) with prominent reliability and sensitivity. The PADs, constructed by in-situ synthesis of blue-emissive carbon dots (CDs) and conjugations of probe DNAs, exhibit the superior uniformity and stability. In the presence of targets, rolling circle amplifications (RCA) are triggered to generate long DNA strands for the assemblies of green-/red-emissive labels. Consequently, remarkable blue-to-green and blue-to-red emission color transitions of the PADs are achieved, implementing the color-analysis of miRNA-21 and circRNA-HIAT1, respectively. Benefited from the efficient RCA, coupled with the drastic ratiometric fluorescent changes, the limit of detections (LODs) of PADs are found to be several fM with the upper limit of the linear detection range at 1 nM. More importantly, the fluorescent PADs possess excellent specificity, as well as anti-interference capability in biological settings, enabling their applications in accurate GC screening with plasma samples. Overall, the proposed fluorescent PADs are featured with robust sensing platform, facile signal readout, and exceptional dual-type RNA sensing performance, holding high potential in point-of-care testing (POCT).


Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Neoplasias Gástricas , Carbono , Detecção Precoce de Câncer , Corantes Fluorescentes , Humanos , RNA , Reprodutibilidade dos Testes , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética
12.
Polymers (Basel) ; 12(10)2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33019518

RESUMO

In this study, a polyol ester from levulinic acid (LA) and trimethylolpropane (TMP) was synthesized by enzymatic catalysis in a solvent-free system. The total conversion of TMP reached up to 84% on average after lipase recycling for five times. The produced ester showed excellent lubrication properties, such as high viscosities at 40 °C (86.53 mm2/s) and 100 °C (8.91 mm2/s), a good viscosity index (49), a low pour point (-27 °C), and a high flash point (223 °C). The frictional wear behavior was evaluated on a four-ball test machine (FTM) by adding the ester into a reference mineral oil. The blend with 10% ester showed a smaller wear scar diameter (WSD) (0.62 mm) when compared with that of pure mineral oil (0.78 mm). The results demonstrated that the obtained ester has huge potential as biolubricant basestock.

13.
Chemosphere ; 78(5): 614-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19913876

RESUMO

We examined physicochemical and biological parameters in order to assess their effectiveness as stability and maturity indicators during the forced-aeration composting process of chicken manure mixed with different amounts of sawdust, yielding initial C/N ratios of 12, 18 and 28. The composting mixture with initial C/N ratio of 28 maintained the temperature exceeding 55 degrees C for more than 3d, but the period with temperature above 55 degrees C in the bottom layer of the composting mixtures with initial C/N ratios of 12 and 18 did not meet the requirement of pathogen destruction. The final electrical conductivity in three composting mixtures did not exceed the limit value of 3000microScm(-1) for stable composts. Only the final NH(4)(+)-N of composting mixture with an initial C/N ratio of 28 did not exceed the limit value of 400mgkg(-1) to be considered a stable compost. The NO(3)(-) content in the three composting mixtures increased with the composting time, and a more pronounced increase was found in the composting mixture with an initial C/N ratio of 28. The final specific oxygen uptake rate was 2.38, 2.35, 0.70mgh(-1)g(-1) organic matter for composting mixtures of initial C/N ratio of 12, 18 and 28, respectively, which suggested a higher stability in composting mixture of initial C/N ratio of 28. The final germination index in composting mixture of initial C/N ratio of 28 was 94%; however, the germination indices in the composting mixtures of initial C/N ratio of 12, 18 were never over 80%.


Assuntos
Esterco , Nitratos/metabolismo , Compostos de Amônio Quaternário/metabolismo , Animais , Bactérias Aeróbias , Biodegradação Ambiental , Galinhas , Concentração de Íons de Hidrogênio , Nitratos/química , Compostos de Amônio Quaternário/química , Temperatura , Madeira
14.
Bioresour Technol ; 101(6): 1899-903, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19897360

RESUMO

The composting of chicken manure and sawdust has been investigated in forced-aeration composting systems at aeration rates of 0.3, 0.5, and 0.7 l min(-1)kg(-1) organic matter (OM), corresponding to pile A, pile B, and pile C. The temperature exceeding 55 degrees C in pile A and pile B remained more than three consecutive days, but only 2 days were above 55 degrees C in pile C. The final electrical conductivity (EC) did not exceed the limit content of 3000 micros cm(-1) in the three piles, and the cation exchange capacity (CEC) met the requirement maturity degree of over 60 c mol kg(-1). The OM loss contents in pile A, pile B, and pile C were 14%, 15.4%, and 12.8%, respectively, corresponding to the final C/N ratio of 17.1, 16.2, and 18.3. The final NH(4)(+)-N content in pile A did not meet the limit value of 400 mg kg(-1), respectively, and the NO(3)(-)-N was 1942, 2190, and 1638 mg kg(-1) in pile A, pile B, and pile C. The final germination index (GI) for pile A, pile B, and pile C was 90.2%, 95.2%, and 79.4%.


Assuntos
Esterco , Amônia/química , Animais , Bactérias Aeróbias , Biodegradação Ambiental , Carbono/química , Galinhas , Condutividade Elétrica , Concentração de Íons de Hidrogênio , Nitratos/química , Nitrogênio/química , Temperatura , Fatores de Tempo , Madeira
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