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1.
Environ Sci Technol ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38832692

RESUMO

Cold heavy oil production with sand (CHOPS) is an extraction process for heavy oil in Canada, with the potential to lead to higher CH4 venting than conventional oil sites, that have not been adequately characterized. In order to quantify CH4 emissions from CHOPS activities, a focused aerial measurement campaign was conducted in the Canadian provinces of Alberta and Saskatchewan in June 2018. Total CH4 emissions from each of 10 clusters of CHOPS wells (containing 22-167 well sites per cluster) were derived using a mass balance computation algorithm that uses in situ wind data measurement on board aircraft. Results show that there is no statistically significant difference in CH4 emissions from CHOPS wells between the two provinces. Cluster-aggregated emission factors (EF) were determined using correspondingly aggregated production volumes. The average CH4 EF was 70.4 ± 36.9 kg/m3 produced oil for the Alberta wells and 55.1 ± 13.7 kg/m3 produced oil for the Saskatchewan wells. Using these EF and heavy oil production volumes reported to provincial regulators, the annual CH4 emissions from CHOPS were estimated to be 121% larger than CHOPS emissions extracted from Canada's National Inventory Report (NIR) for Saskatchewan. The EF were found to be positively correlated with the percentage of nonpiped production volumes in each cluster, indicating higher emissions for nonpiped wells while suggesting an avenue for methane emission reductions. A comparison with recent measurements indicates relatively limited effectiveness of regulations for Saskatchewan compared to those in Alberta. The results of this study indicate the substantial contribution of CHOPS operations to the underreporting observed in the NIR and provide measurement-based EF that can be used to develop improved emissions inventories for this sector and mitigate CH4 emissions from CHOPS operations.

2.
Eur J Med Res ; 29(1): 283, 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38735989

RESUMO

BACKGROUND: It remains unclear whether additional fluid supplementation is necessary during the acute resuscitation period for patients with combined inhalational injury (INHI) under the guidance of the Third Military Medical University (TMMU) protocol. METHODS: A 10-year multicenter, retrospective cohort study, involved patients with burns ≥ 50% total burn surface area (TBSA) was conducted. The effect of INHI, INHI severity, and tracheotomy on the fluid management in burn patients was assessed. Cumulative fluid administration, cumulative urine output, and cumulative fluid retention within 72 h were collected and systematically analyzed. RESULTS: A total of 108 patients were included in the analysis, 85 with concomitant INHI and 23 with thermal burn alone. There was no significant difference in total fluid administration during the 72-h post-burn between the INHI and non-INHI groups. Although no difference in the urine output and fluid retention was shown in the first 24 h, the INHI group had a significantly lower cumulative urine output and a higher cumulative fluid retention in the 48-h and 72-h post-burn (all p < 0.05). In addition, patients with severe INHI exhibited a significantly elevated incidence of complications (Pneumonia, 47.0% vs. 11.8%, p = 0.012), (AKI, 23.5% vs. 2.9%, p = 0.037). For patients with combined INHI, neither the severity of INHI nor the presence of a tracheotomy had any significant influence on fluid management during the acute resuscitation period. CONCLUSIONS: Additional fluid administration may be unnecessary in major burn patients with INHI under the guidance of the TMMU protocol.


Assuntos
Queimaduras , Hidratação , Ressuscitação , Humanos , Hidratação/métodos , Masculino , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Adulto , Queimaduras/terapia , Queimaduras/complicações , Ressuscitação/métodos
3.
ACS Appl Mater Interfaces ; 16(19): 24879-24888, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38695482

RESUMO

Upconversion luminescence plays a crucial role in various technological applications, and among the various valence states of lanthanide elements, Ln3+ has the highest stability. The 4f orbitals of these elements are in a fully empty, semifull, or full state. This special 4f electron configuration allows them to exhibit rich discrete energy levels. However, the 4f-4f transition of Ln3+ rare earth ions itself is prohibited, resulting in a lower luminescence efficiency. This limitation greatly hinders the practical application of upconversion luminescence. In this study, we report nanostructured luminescence-enhanced substrate platforms with both semiconductive local surface plasmons and spatially confined domain effects on a single defect semiconductor substrate. By coupling NaYF4:Yb-Er nanoparticle emitters to the surface of Ti3O5 NC-arrays plasmonic nanostructures, an ultrabright luminescence with a 32-fold increase in green emission and a 40-fold increase in red emission was achieved. Furthermore, the fluorescence resonance energy transfer characteristics observed in the R6G/NaYF4/Ti3O5 NC-array composite film enable accurate detection of fluorescent molecules. The results provide an innovative and intelligent approach to enhance the upconversion luminescence intensity of rare-doped nanoparticles and develop highly sensitive molecular detection systems based on the above luminescence enhancement.

4.
Water Res ; 257: 121664, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38678836

RESUMO

Understanding the chemical composition, origin, and molecular structure of dissolved organic matter (DOM) in multi-interface runoff is essential for comprehending the fate of laterally transported DOM in complex soil-epikarst systems of karst hillslopes. Limited information, however, is available for the optical properties and molecular compositions of the transported OM in multiple runoff components on the karst hillslope in relation to land-uses and soil thicknesses. In this study, we conducted a study to observe the changes in the quantity and quality of DOM in multiple interface flow (surface, subsurface, and epikarst) during natural rainfall events in 2022 in karst hillslopes that are covered by different land uses (cropland and shrubland) and soil thicknesses (with mean depths of 66.0 cm for deeper soil and 35.4 cm for shallower soil) in the karst region of southwest China. chemcial compositions of runoff DOM were determined by optical analysis and microbial compositions in runoff were inferred with high-throughput sequencing. The results showed that the soil-epikarst structure was controlling the runoff DOM quantity and quality during rainfall events. A decrease in the aromaticity, humification, unsaturation, and oxidation degree and an increase in carbohydrate, aminosugars, protein, and lipid compounds were found from surface to epikarst flow, indicating that plant-and soil-derived carbon decreased, while the microbially-derived carbon increased. The results were further comfirmed by the higher bacterial richness and diversity, along with fungal diversity in the epikarst flow compared to other runoff components. The bio-labile protein materials (C2) were the most important component of runoff DOM output in karst hillslopes. In surface and subsurface flow, rainfall amount, runoff rate, and discharge significantly affected the DOM concentration and quality during rainfalls, indicating that the dynamics of DOM in runoff from karst hillslopes were predominantly influenced by hydrological processes. Furthermore, the runoff DOM quality in cropland was dominated by lower unsaturation and oxidation degrees and higher protein component, compared to those in shrubland. The compositions of DOM in runoff from hillslope plots with thicker soils were primarily characterized by microbially-derived materials. Our findings were conducive to understanding the mechanism governing the migration of DOM quality and quantity in discharge during multi-interface hydrological processes on karst hillslopes.


Assuntos
Chuva , Solo , Solo/química , China , Monitoramento Ambiental , Compostos Orgânicos/análise , Movimentos da Água
5.
J Inflamm Res ; 17: 1365-1375, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38439928

RESUMO

Objective: To explore the correlation between serum uric acid (SUA) trajectories and new-onset hypertension, to provide scientific basis for the prevention and treatment of hypertension. Methods: The study cohort was composed of 4372 subjects who met the inclusion criteria in the cohort study of Henan physical examination population. According to the SUA values of the subjects' physical examination from 2017 to 2019, three different SUA trajectory groups were determined by R LCTM tools, namely low stability group, medium stability group and high stability group. The incidence of hypertension during physical examination in 2020 was followed up, the cumulative incidence rate in each group was calculated by product limit method, and the correlation between different SUA trajectories and new-onset hypertension was analyzed by Cox proportional hazards regression model. Results: The incidence rate of hypertension increased with the increase of SUA locus, which was 4.65%, 9.18% and 12.43% respectively, and the difference was statistically significant (P<0.001). After adjusting multiple confounding factors, such as gender, waist circumference (WC), blood pressure, body mass index (BMI), fasting plasma glucose (FPG) and blood lipid by Cox proportional hazards regression model, the risk of hypertension in SUA medium stability and high stability group was still 1.476 times (95% CI: 1.089~2.000) and 1.692 times (95% CI: 1.152~2.484) of low-stable SUA group (P<0.05). Conclusion: The risk of hypertension increases with the increase of SUA level in the long-term normal range. It is necessary to carry out the intervention for hypertension with long-term normal high value to avoid the progress of hypertension disease, to achieve the purpose of early prevention of hypertension.

6.
Opt Lett ; 49(5): 1305-1308, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38426999

RESUMO

Temperature characteristics of GaN-based laser diodes are investigated. It is noted that the characteristic temperature of the threshold current (T0) decreases with decreasing lasing wavelength for GaN-based LDs. The performance deteriorates seriously for UV LDs at high temperature. It is ascribed to the increase of carriers escaping from quantum wells due to the lower potential barrier height. In this Letter, AlGaN is used as the barrier layer in UV LDs instead of GaN to improve the temperature characteristic of the threshold current and slope efficiency by increasing the potential barrier height of quantum wells. Based on this structure, a high output power of 4.6 W is obtained at the injection current of 3.8 A; its lasing wavelength is 386.8 nm.

7.
Transl Vis Sci Technol ; 13(2): 5, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38329750

RESUMO

Purpose: To investigate the relationship between Acanthamoeba genotypes, clinical manifestations, and outcomes in Acanthamoeba keratitis (AK) patients. Methods: This retrospective study included 159 culture-confirmed AK patients. Patients' data were collected, including demographics, initial diagnosis, treatments, and clinical features. The genotype of Acanthamoeba was identified through sequencing the Diagnostic Fragment 3 (DF3) region in the small ribosomal subunit RNA genes. The phylogenetic tree was constructed using the ClustalW model and maximum likelihood method. Cases with "poor outcome" were defined based on specific clinical criteria, including corneal perforation, keratoplasty, other eye surgery, duration of anti-amoebic therapy ≥8.0 months, and final visual acuity ≤20/80. "Better outcome" cases were the remainder. The correlation between T4 subtypes, clinical phenotypes, and clinical prognosis were further analyzed. Results: In this study, AK was primarily attributed to the T4A genotype, with a positive correlation between geographical and genetic distances. The primary clinical associated with T4 subtypes was deep stromal infiltration. Results was also showed a significant association between T4 subtypes and clinical outcomes (P = 0.021). Further analysis revealed that T4C was closely associated with a better prognosis (P = 0.040) and T4D with worse outcomes (P = 0.013). Conclusions: In China, AK was predominantly caused by the T4A subtype. Geographical distance positively correlated with genetic distance. Clinical prognosis varied among different subtypes, notably in T4C and T4D. Translational Relevance: This study demonstrated the association between T4 subtypes and clinical phenotypes, as well as the effects of T4 subtypes on clinical prognosis.


Assuntos
Ceratite por Acanthamoeba , Humanos , Ceratite por Acanthamoeba/diagnóstico , Filogenia , Estudos Retrospectivos , Genótipo , China/epidemiologia
8.
J Cosmet Dermatol ; 23(6): 2199-2208, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38400620

RESUMO

BACKGROUND: Prevailing tension-reducing suture methods have a spectrum of issues. This study presents a straightforward yet highly efficacious suture technique known as the Split-level Folding, Step-type Tension-relieving Suture technique, which could play a pivotal role in preempting incisional scarring. AIMS: To introduce Split-level Folding, Step-type Tension-relieving Suture technique and assess its effect on scar minimization. METHODS: A retrospective analysis of 64 patients who underwent treatment utilizing the proposed suturing methodology. Assessment parameters included the Patient and Observer Scar Assessment Scale (POSAS), the Vancouver Scar Scale (VSS), scar width, complications, and all evaluated at 6- and 12-month postoperatively. RESULTS: At 12-month follow-up, the POSAS and VSS scores in the normal suture group (32.58 ± 5.43, 3.58 ± 1.39) were considerably higher than the step-type suture group (29.75 ± 3.56, p = 0.0007; 2.78 ± 1.17, p = 0.0006). Moreover, the step-type suture group showcased a significantly narrower average incision scar width (1.62 ± 0.36) than the normal suture group (1.87 ± 0.42, p = 0.0004). This novel tension-relieving suture technique that effectively circumvents the occurrence of persistent localized eversion and other complications often associated with traditional tension-relieving sutures. CONCLUSIONS: The Split-level Folding, Step-type Tension-relieving Suture technique emerges as a highly promising option for averting incisional scarring. This suture method works well for incisions on the chest, back, and extremities, resulting in significantly better long-term outcomes.


Assuntos
Cicatriz , Técnicas de Sutura , Humanos , Técnicas de Sutura/efeitos adversos , Cicatriz/etiologia , Cicatriz/prevenção & controle , Estudos Retrospectivos , Feminino , Adulto , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Seguimentos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Suturas/efeitos adversos , Adulto Jovem
10.
Angew Chem Int Ed Engl ; 63(9): e202315740, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38195825

RESUMO

Nanostructured conjugated polymers are of widespread interest due to their broad applications in organic optoelectronic devices, biomedical sensors and other fields. However, the alignment of conjugated nanostructures perpendicular to a surface remains a critical challenge. Herein, we report a facile method to directly self-assemble a poly(3-(2-ethylhexyl)thiophene), P3EHT-based block copolymer into densely aligned micellar brushes through surface-initiated living crystallization-driven self-assembly. The presence of an ethyl pendant on the side group intrinsically moderates the crystallization rate of the polythiophene main chains, and hence favors the controlled living growth of long conjugated fibers and the subsequent fabrication of conjugated micellar brushes. The corona of the micellar brush can be further decorated with platinum nanoparticles, which enables the formation of erect nanoarrays with heights up to 2700 nm in the dried state. This also renders the micellar brush catalytically active toward hydrogen evolution reaction, which shows a low overpotential of 27 mV at 10 mA cm-2 . Notably, the P3EHT-based micellar brush can simultaneously grow with polyferrocenyldimethylsilane, PFS-based micellar brush on the same surface without any significant interference between the two systems. Thus, these two micellar brushes can be patterned through site-selective immobilization of two types of seeds followed by independent living self-assembly.

12.
Ocul Immunol Inflamm ; 32(1): 79-88, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36622888

RESUMO

PURPOSE: To examine whether corneal epithelial dendritic cells (CEDC) could serve as an indicator to distinguish obstructive meibomian gland dysfunction (MGD) with or without ocular surface inflammation (OSI). METHODS: We performed a case-control study on patients with diagnosed obstructive MGD between August 2017 and November 2019. RESULTS: 30 MGD cases and 25 healthy controls were recruited. The classification of MGD patients with and without OSI was based on the tear pro-inflammatory cytokine levels. Compared with the MGD without OSI and the control group, a higher CEDC density was detected in the MGD with OSI subgroup. The presence of >15.6 cells/mm2 CEDC had a sensitivity of 73% and specificity of 75% for the diagnosis of MGD with OSI. CONCLUSIONS: OSI is not present in all patients with obstructive MGD. Evaluation of CEDC density in the central cornea may help identify whether MGD is concomitant with OSI.


Assuntos
Síndromes do Olho Seco , Doenças Palpebrais , Disfunção da Glândula Tarsal , Humanos , Estudos de Casos e Controles , Glândulas Tarsais , Doenças Palpebrais/diagnóstico , Lágrimas , Células Dendríticas , Síndromes do Olho Seco/diagnóstico
13.
Adv Mater ; 36(5): e2309376, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37914405

RESUMO

Covalent triazine frameworks (CTFs) are emerging as a promising molecular platform for photocatalysis. Nevertheless, the construction of highly effective charge transfer pathways in CTFs for oriented delivery of photoexcited electrons to enhance photocatalytic performance remains highly challenging. Herein, a molecular engineering strategy is presented to achieve highly efficient charge separation and transport in both the lateral and vertical directions for solar-to-formate conversion. Specifically, a large π-delocalized and π-stacked Schottky junction (Ru-Th-CTF/RGO) that synergistically knits a rebuilt extended π-delocalized network of the D-A1 -A2 system (multiple donor or acceptor units, Ru-Th-CTF) with reduced graphene oxide (RGO) is developed. It is verified that the single-site Ru units in Ru-Th-CTF/RGO act as effective secondary electron acceptors in the lateral direction for multistage charge separation/transport. Simultaneously, the π-stacked and covalently bonded graphene is regarded as a hole extraction layer, accelerating the separation/transport of the photogenerated charges in the vertical direction over the Ru-Th-CTF/RGO Schottky junction with full use of photogenerated electrons for the reduction reaction. Thus, the obtained photocatalyst has an excellent CO2 -to-formate conversion rate (≈11050 µmol g-1 h-1 ) and selectivity (≈99%), producing a state-of-the-art catalyst for the heterogeneous conversion of CO2 to formate without an extra photosensitizer.

14.
Opt Express ; 31(24): 39695-39702, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38041285

RESUMO

The influence of growth interruption on the surface and luminescence properties of AlGaN/GaN ultraviolet multi-quantum wells (UV MQWs) is investigated. It is found that when the well and barrier layers of MQW samples are continuously grown at the same temperature, they have lower edge dislocation density and flatter surface of MQWs compared to samples with interrupted well and barrier growth. Moreover, continuous growth of well and barrier layers is more conducive to improving the luminescence efficiency of MQWs. This phenomenon is attributed to more impurity incorporation induced by the growth interruption, while a continuous growth of well and barrier can reduce surface diffusion and migration processes of atoms, reducing the defects and surface roughness of MQWs. In addition, the continuous growth of well and barrier can better control the reaction between Al and N atoms, avoiding the formation of excessively high Al content AlGaN at the well/barrier interface, thus improving the luminescence of UV MQWs.

15.
Infect Immun ; 91(11): e0010323, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37874164

RESUMO

In eukaryotes, autophagy is induced as an innate defense mechanism against pathogenic microorganisms by self-degradation. Although trichinellosis is a foodborne zoonotic disease, there are few reports on the interplay between Trichinella spiralissurvival strategies and autophagy-mediated host defense. Therefore, this study focused on the association between T. spiralis and autophagy of host small intestinal cells. In this study, the autophagy-related indexes of host small intestinal cells after T. spiralis infection were detected using transmission electron microscopy, hematoxylin and eosin staining, immunohistochemistry, quantitative real-time polymerase chain reaction, and Western blotting. The results showed that autophagosomes and autolysosomes were formed in small intestinal cells, intestinal villi appeared edema, epithelial compactness was decreased, microtubule-associated protein 1A/1B-light chain 3B (LC3B) was expressed in lamina propria stromal cells of small intestine, and the expression of autophagy-related genes and proteins was changed significantly, indicating that T. spiralis induced autophagy of host small intestinal cells. Then, the effect of T. spiralis on autophagy-related pathways was explored by Western blotting. The results showed that the expression of autophagy-related pathway proteins was changed, indicating that T. spiralis regulated autophagy by affecting autophagy-related pathways. Finally, the roles of T. spiralis serine protease inhibitors (TsSPIs), such as T. spiralis Kazal-type SPI (TsKaSPI) and T. spiralis Serpin-type SPI (TsAdSPI), were further discussed in vitro and in vivo experiments. The results revealed that TsSPIs induced autophagy by influencing autophagy-related pathways, and TsAdSPI has more advantages. Overall, our results indicated that T. spiralis induced autophagy of host small intestinal cells, and its TsSPIs play an important role in enhancing autophagy flux by affecting autophagy-related pathways. These findings lay a foundation for further exploring the pathogenesis of intestinal dysfunction of host after T. spiralis infection, and also provide some experimental and theoretical basis for the prevention and treatment of trichinellosis.


Assuntos
Trichinella spiralis , Triquinelose , Animais , Camundongos , Trichinella spiralis/genética , Trichinella spiralis/metabolismo , Triquinelose/metabolismo , Inibidores de Serina Proteinase/genética , Inibidores de Serina Proteinase/metabolismo , Intestino Delgado , Autofagia , Camundongos Endogâmicos BALB C
16.
ACS Biomater Sci Eng ; 9(11): 6241-6255, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37823558

RESUMO

Novel full-thickness skin substitutes are of increasing interest due to the inherent limitations of current models lacking capillary networks. Herein, we developed a novel full-thickness skin tissue containing blood capillary networks through a layer-by-layer assembly approach using a handy electrospinning apparatus and evaluated its skin wound coverage potential in vivo. The average diameter and thickness of fabricated poly-ε-caprolactone-cellulose acetate scaffolds were easily tuned in the range of 474 ± 77-758 ± 113 nm and 9.43 ± 2.23-29.96 ± 5.78 µm by varying electrospinning distance and duration, as indicated by FE-SEM. Besides, keratinocytes exhibited homogeneous differentiation throughout the fibrous matrix prepared with electrospinning distance and duration of 9 cm and 1.5 min within five-layer (5L) epidermal tissues with thickness of 135-150 µm. Moreover, coculture of vascular endothelial cells, circulating fibrocytes, and fibroblasts within the 5L dermis displayed network formation in vitro, resulting in reduced inflammatory factor levels and enhanced integration with the host vasculature in vivo. Additionally, the skin equivalent grafts consisting of the epidermal layer, biomimetic basement membrane, and vascularized dermis layer with an elastic modulus of approximately 11.82 MPa exhibited accelerated wound closure effect indicative of re-epithelialization and neovascularization with long-term cell survival into the host, which was confirmed by wound-healing rate, bioluminescence imaging activity, and histological analysis. It is the first report of a full-thickness skin equivalent constructed using a battery-operated electrospinning apparatus, highlighting its tremendous potential in regenerative medicine.


Assuntos
Células Endoteliais , Pele , Pele/irrigação sanguínea , Queratinócitos , Cicatrização , Transplante de Pele
17.
Ecotoxicol Environ Saf ; 264: 115466, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37714037

RESUMO

Calcium peroxide (CP) is an oxidizing agent that can gradually release hydrogen peroxide (HP) to achieve selective killing of cyanobacteria in water blooms, and reduce the phosphorus content in the water column. Despite the potential of CP for use in cyanobacterial water bloom disposal, there is a lack of research on the mechanism of oxidative damage on cyanobacterial cells by calcium peroxide. Further studies are required to comprehend the underlying scientific principles and potential risks and benefits of applying this approach to cyanobacteria disposal. In this investigation, we employed varying doses of CP for the treatment of Microcystis aeruginosa (M. aeruginosa), which resulted in the following findings: (1) the HP released from CP can damage the photosystem II of M. aeruginosa, reduce cell photosynthetic pigment content, intensify the degree of membrane lipid peroxidation, and increase the extracellular protein content; (2) CP significantly increased the soluble extracellular polysaccharide (sEPS) and bound extracellular polysaccharide (bEPS) content of cells (p < 0.05), causing the cells to exist as agglomerates and effectively allowing them to flocculate and precipitate, reducing the turbidity of the water body; (3) The increased dose elevated the pH and calcium ions significantly decreased the orthophosphate content, resulting in an increase in extracellular alkaline phosphatase activity, but possibly increasing the total extracellular nitrogen content. These results suggested that CP is an effective chemical algaecide for cyanobacteria, and has the potential to be applied to dispose of cyanobacterial blooms while reducing the phosphorus content of the water column and further inhibiting the growth and proliferation of cells.


Assuntos
Microcystis , Peróxido de Hidrogênio , Oxidantes , Fósforo
18.
Nat Aging ; 3(10): 1288-1311, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37697166

RESUMO

As important immune cells, microglia undergo a series of alterations during aging that increase the susceptibility to brain dysfunctions. However, the longitudinal characteristics of microglia remain poorly understood. In this study, we mapped the transcriptional and epigenetic profiles of microglia from 3- to 24-month-old mice. We first discovered unexpected sex differences and identified age-dependent microglia (ADEM) genes during the aging process. We then compared the features of aging and reactivity in female microglia at single-cell resolution and epigenetic level. To dissect functions of aged microglia excluding the influence from other aged brain cells, we established an accelerated microglial turnover model without directly affecting other brain cells. By this model, we achieved aged-like microglia in non-aged brains and confirmed that aged-like microglia per se contribute to cognitive decline. Collectively, our work provides a comprehensive resource for decoding the aging process of microglia, shedding light on how microglia maintain brain functions.


Assuntos
Disfunção Cognitiva , Microglia , Feminino , Camundongos , Masculino , Animais , Encéfalo , Envelhecimento/genética , Disfunção Cognitiva/genética , Epigênese Genética
19.
Acta Biomater ; 170: 389-400, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37625678

RESUMO

One of the serious threats to global public health is the bacterial biofilm, which results in numerous persistent and recurrent infections. Herein, we proposed a near-infrared (NIR) light-triggered "nano-domino" system with "dispersing and killing" functionality for biofilm eradication. The nanoplatform was fabricated by the self-assembly of chitosan conjugated with L-arginine (L-Arg, a natural nitric oxide (NO) donor) and indocyanine green (ICG, a phototherapy agent). Using an NIR irradiation "trigger", a series of reactive oxygen species (ROS) including singlet oxygen (1O2), hydrogen peroxide (H2O2), and superoxide anions (·O2-), as well as heat were generated from ICG aggregates. Subsequently, 1O2 and H2O2 catalyzed L-Arg to produce NO, which dispersed the biofilm and reacted with ·O2- to form peroxynitrite to kill bacteria with ROS collaboratively. Meanwhile, the generated heat increased the permeability of bacterial membranes, aggravating the damage to biofilm bacteria. The experiments on biofilm eradication demonstrated that this "nano-domino" system was capable to eradicate over 99.99% of biofilms formed by Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa under 5-min NIR irradiation. Notably, these integrated benefits allowed the system to promote the healing of MRSA biofilm-infected wounds in vivo with negligible toxicity. Overall, this reported NIR-triggered "nano-domino" system holds great promise for addressing the difficulties associated with bacterial biofilm eradication. STATEMENT OF SIGNIFICANCE: Novel agents for biofilm eradication are urgently needed due to the alarming rise in antimicrobial resistance to conventional antibiotics and the critical shortage of new drugs. In this study, we created a nano-domino system that uses near-infrared (NIR) light as a trigger to eradicate mature biofilms. In response to a short-term NIR irradiation, the proposed nanoplatform could generate nitric oxide and peroxynitrite to disperse the biofilm and kill the bacteria inside, respectively, leading to efficient eradication of Methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa biofilms with minimal cytotoxicity. The findings, therefore, indicate that this nanoplatform with enhanced antibiofilm performance might provide a reliable and promising solution to biofilm-related problems.

20.
J Fluoresc ; 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37646873

RESUMO

To promote the application of time-resolved fluorescence in oxidation determination of edible vegetable oil, fluorescence lifetime of chlorophyll α in oxidized edible vegetable oils was recorded and analyzed by simulated microenvironment experiments and spectral methods. It was showed that fluorescence lifetime of chlorophyll α decreased with the increase of polarity in the early stage of oxidation, and increased with the increase of viscosity in the later stage of oxidation. Conjugation effect and hydrogen bonding existed in the microenvironment of oxidized edible vegetable oil were considered to be the factors leading to the increase of fluorescence lifetime. The change mechanism of fluorescence lifetime in oxidized edible vegetable oil was supplied, which was considered to be strong support for the application of time-resolved fluorescence.

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