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1.
PLoS One ; 19(4): e0299399, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38607987

RESUMO

In this study, we employed the principle of Relative Mode Transfer Method (RMTM) to establish a model for a single pendulum subjected to sudden changes in its length. An experimental platform for image processing was constructed to accurately track the position of a moving ball, enabling experimental verification of the pendulum's motion under specific operating conditions. The experimental data demonstrated excellent agreement with simulated numerical results, validating the effectiveness of the proposed methodology. Furthermore, we performed simulations of a double obstacle pendulum system, investigating the effects of different parameters, including obstacle pin positions, quantities, and initial release angles, on the pendulum's motion through numerical simulations. This research provides novel insights into addressing the challenges associated with abrupt and continuous changes in pendulum length.


Assuntos
Processamento de Imagem Assistida por Computador , Modalidades de Fisioterapia , Movimento (Física)
2.
Inflammopharmacology ; 32(2): 975-989, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38429613

RESUMO

Fibrosis is a prevailing pathology in chronic diseases and accounts for 45% of deaths in developed countries. This condition is primarily identified by the transformation of fibroblasts into myofibroblasts and the overproduction of extracellular matrix (ECM) by myofibroblasts. Pterostilbene (PTS) is a natural analogue of resveratrol and is most commonly found in blueberries. Research has shown that PTS exerts a wide range of pharmacological effects, such as antioxidant, anti-inflammatory, and anticancer effects. As a result, PTS has the potential to prevent and cure numerous diseases. Emerging evidence has indicated that PTS can alleviate myocardial fibrosis, renal fibrosis, pulmonary fibrosis, hepatic fibrosis, and colon fibrosis via the inhibition of inflammation, oxidative stress, and fibrogenesis effects in vivo and in vitro, and the potential mechanisms are linked to various pathways, including transforming growth factor-ß1 (TGF-ß1)/small mother against decapentaplegic proteins (Smads) signalling, the reactive oxygen species (ROS)-driven Pitx2c/mir-15b pathway, nuclear factor kappa B (NF-κB) signalling, Kelch-like epichlorohydrin-associated protein-1 (Keap-1)/NF-E2-related factor-2 (Nrf2) cascade, the NLR family pyridine structure domain 3 (NLRP3) pathway, the Janus kinase-2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway, and the Src/STAT3 pathway. In this review, we comprehensively summarize the antifibrotic effects of PTS both in vivo and in vitro and the pharmacological mechanisms, pharmacokinetics, and toxicology of PTS and provide insights into and strategies for exploring promising agents for the treatment of fibrosis.


Assuntos
Estresse Oxidativo , Fibrose Pulmonar , Humanos , Fibrose , Fibrose Pulmonar/tratamento farmacológico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Antioxidantes/metabolismo , Cirrose Hepática/metabolismo
3.
Chem Res Toxicol ; 37(3): 451-454, 2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38417054

RESUMO

Alkyl phosphotriester (alkyl-PTE) lesions in DNA are shown to be poorly repaired; however, little is known about how these lesions impact DNA replication in human cells. Here, we investigated how the SP and RP diastereomers of four alkyl-PTE lesions (alkyl = Me, Et, nPr, or nBu) at the TT site perturb DNA replication in HEK293T cells. We found that these lesions moderately impede DNA replication and that their replicative bypass is accurate. Moreover, CRISPR-Cas9-mediated depletion of Pol η or Pol ζ resulted in significantly attenuated bypass efficiencies for both diastereomers of nPr- and nBu-PTE adducts, and the SP diastereomer of Et-PTE. Diminished bypass efficiencies were also detected for the Rp diastereomer of nPr- and nBu-PTE lesions upon ablation of Pol κ. Together, our study uncovered the impact of the alkyl-PTE lesions on DNA replication in human cells and revealed the roles of individual translesion synthesis DNA polymerases in bypassing these lesions.


Assuntos
Replicação do DNA , Humanos , Células HEK293
4.
J Nat Prod ; 87(1): 160-165, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-38194474

RESUMO

One novel rearranged pimarane diterpenoid, pestanoid A (1), and two reported molecules, nodulisporenones A (2) and B (3), were discovered from Pestalotiopsis sp. NBUF145 fungus associated with a 62 m deep mesophotic ("twilight") zone Chalinidae sponge. The structures of 1-3 were identified by spectrometry, spectroscopy, quantum-chemical calculations, and X-ray crystallography. Compounds 1 and 2 inhibited bone marrow monocyte osteoclastogenesis in vitro with the IC50 values 4.2 ± 0.2 µM and 3.0 ± 0.4 µM, respectively, without observed cytotoxicity. Both 1 and 2 suppressed the receptor activator of NF-kB ligand-induced MAPK and NF-κB signaling by inhibiting the phosphorylation of ERK1/2-JNK1/2-p38 MAPKs and NF-κB nuclear translocation.


Assuntos
Osteoclastos , Osteogênese , NF-kappa B , Pestalotiopsis , Macrófagos , Abietanos , Ligante RANK
5.
Int Immunopharmacol ; 127: 111333, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38091829

RESUMO

BACKGROUND: In the majority of clinical environments, the treponema pallidum particle agglutination (TPPA) test is known for its higher specificity compared to the rapid plasma reagin (RPR) test and is commonly employed for the diagnosis of syphilis, but their use for serological monitoring after syphilis therapy is controversial. OBJECTIVES: We aim to evaluate whether the TPPA titers is suitable for monitoring syphilis treatment efficacy. METHODS: At first, 232 patients with primary syphilis were recruited. Serological testing was performed at baseline (initial visit) and at 6 months (±1 month) after benzathine penicillin G (BPG) treatment. Second, New Zealand white male rabbits were infected with Treponema pallidum (T. pallidum) to evaluate the changes in TPPA titers after BPG therapy. Finally, we compared the TPPA titers in the culture supernatant of rabbit splenocytes stimulated with T. pallidum with or without BPG. RESULTS: After 6 months of treatment, 150 (64.7%) of 232 primary syphilis patients achieved serological cure, and 82 (35.3%) had adverse outcomes. Among 110 patients with TPPA titers decreased by more than fourfold, 109 of them were serological cure patients (≥4-fold decrease in RPR titers) (P < 0.0001). In the rabbit model of syphilis, the TPPA titers was significantly decreased in the treatment subgroup (P = 0.016) and remained constant (±2-fold) or increased (≥4-fold) in the nontreatment subgroup. In addition, T. pallidum resulted in a positive TPPA titers in the culture supernatant of splenocytes (median titers was 1: 80), while BPG could directly reduce the TPPA titers in the culture supernatant (median titers was 1: 40) (P = 0.032). CONCLUSIONS: A 4-fold or greater decrease in TPPA titers may indicate effective treatment in primary syphilis. Combining TPPA titers with RPR titers results may potentially aid in the early diagnosis of syphilis.


Assuntos
Sífilis , Humanos , Masculino , Animais , Coelhos , Sífilis/diagnóstico , Sífilis/tratamento farmacológico , Treponema pallidum , Penicilina G Benzatina/uso terapêutico , Sorodiagnóstico da Sífilis , Resultado do Tratamento , Aglutinação
6.
Small ; 20(8): e2303473, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37840383

RESUMO

Hierarchical porous materials have attracted the attention of researchers due to their enormous specific surface area, maximized active site utilization efficiency, and unique structure and properties. In this context, metal-organic frameworks (MOFs) offer a unique mix of properties that make them particularly appealing as tunable porous substrates containing highly active sites. This review focuses on recent advances in the types and synthetic strategies of hierarchical porous MOFs and their derived materials. Furthermore, it highlights the relationship between the mass diffusion and transport of hierarchical porous structures and the pore size with examples and simulations, while identifying their potential and limitations. On this basis, how the synthesis conditions affect the structure and electrochemical properties of MOFs based hierarchical porous materials with different structures is discussed, highlighting the prospects and challenges for the synthetization, as well as further scientific research and practical applications. Finally, some insights into current research and future design ideas for advanced MOFs based hierarchical porous materials are presented.

7.
Adv Mater ; 36(7): e2309266, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38019100

RESUMO

Many perovskite oxides (ABO3 ) are considered the most promising alternatives to noble metal catalysts for oxygen reduction reaction (ORR) due to their high intrinsic activities. However, their electrocatalytic performance is often limited by poor electrical conductivity and low specific surface area. Here an electrochemically induced calcium-leaching process is reported to greatly increase the electrochemical surface area (ECSA) of La0.6 Ca0.4 MnO3 (LCMO64). The ECSA of the activated, Ca-deficient LCMO64 is ≈33.84% higher than that of the unactivated materials, demonstrating superior electrocatalytic ORR performance to the benchmark commercial Pt/C catalyst in an alkaline solution. Theoretical analysis coupled with electrochemical surface state probing and pH-dependent microkinetic modeling suggests that this catalyst with the identified most favorable state under ORR operating conditions reaches the Sabatier optimum of alkaline ORR. This reconstructed LCMO64 is among the best-performing ORR catalysts ever reported, providing new insights into the design of advanced perovskite materials with optimal surface chemistry.

8.
Pediatr Rheumatol Online J ; 21(1): 130, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872565

RESUMO

OBJECTIVES: Systemic lupus erythematosus is an autoimmune disease that involves multiple organ systems. One of its major complications, lupus nephritis (LN), is associated with a high mortality rate, and children-onset LN have a more severe course and worse prognosis than adults. Oxidative stress and inflammatory responses are involved in LN development and pathogenesis. Thus, this study aimed to explore the role of signaling regulation of the Nrf2/HMGB1/TLR/NF-κB pathway in LN pathogenesis and unravel the expression of TLR4+CXCR4+ plasma cells subset (PCs) in LN. METHODS: C57BL/6 and MRL/lpr mice were divided into four groups: control, model, vector control, and Nrf2 overexpression groups. The vector control and Nrf2 overexpression groups were injected with adenoviral vectors into the kidney in situ. Pathological changes in kidney tissues were observed by hematoxylin-eosin staining. The expression of Nrf2, HMGB1, TLR4, NF-κB, and downstream inflammatory factors in kidney samples was analyzed by quantitative polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay. The ratios of TLR4+CXCR4+ PC subsets in the blood and kidneys of mice were determined by flow cytometry. RESULTS: In MRL/lpr mice, Nrf2 was downregulated while HMGB1/TLR4/NF-κB pathway proteins were upregulated. Nrf2 overexpression decreased the expression of HMGB1, TLR4, NF-κB, and its downstream inflammatory cytokines (IL-1ß and TNFα). These cytokines were negatively correlated with an increase in Nrf2 content. PC and TLR4 + CXCR4 + PCs in the blood and kidney samples were significantly increased in MRL/lpr mice; however, they were decreased upon Nrf2 overexpression. CONCLUSION: This study showed severe kidney injury in an LN mouse model and an increased ratio of TLR4 + CXCR4 + PCs. Furthermore, we observed that Nrf2 regulates LN immune response through the Nrf2/HMGB1/TLR4/NF-κB pathway, which can be considered an important target for LN treatment. The clinical value of the findings of our study requires further investigation.


Assuntos
Nefrite Lúpica , Fator 2 Relacionado a NF-E2 , Transdução de Sinais , Animais , Criança , Humanos , Camundongos , Citocinas/metabolismo , Proteína HMGB1/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos MRL lpr , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo
9.
Sci Adv ; 9(42): eadi8025, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37851800

RESUMO

The anode corrosion induced by the harsh acidic and oxidative environment greatly restricts the lifespan of catalysts. Here, we propose an antioxidation strategy to mitigate Ir dissolution by triggering strong electronic interaction via elaborately constructing a heterostructured Ir-Sn pair-site catalyst. The formation of Ir-Sn dual-site at the heterointerface and the resulting strong electronic interactions considerably reduce d-band holes of Ir species during both the synthesis and the oxygen evolution reaction processes and suppress their overoxidation, enabling the catalyst with substantially boosted corrosion resistance. Consequently, the optimized catalyst exhibits a high mass activity of 4.4 A mgIr-1 at an overpotential of 320 mV and outstanding long-term stability. A proton-exchange-membrane water electrolyzer using this catalyst delivers a current density of 2 A cm-2 at 1.711 V and low degradation in an accelerated aging test. Theoretical calculations unravel that the oxygen radicals induced by the π* interaction between Ir 5d-O 2p might be responsible for the boosted activity and durability.

10.
Adv Mater ; : e2305508, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37725694

RESUMO

Electrochemical CO2 conversion to value-added multicarbon (C2+ ) chemicals holds promise for reducing CO2 emissions and advancing carbon neutrality. However, achieving both high conversion rate and selectivity remains challenging due to the limited active sites on catalysts for carbon-carbon (C─C) coupling. Herein, porous CuO is coated with amorphous CuSiO3 (p-CuSiO3 /CuO) to maximize the active interface sites, enabling efficient CO2 reduction to C2+ products. Significantly, the p-CuSiO3 /CuO catalyst exhibits impressive C2+ Faradaic efficiency (FE) of 77.8% in an H-cell at -1.2 V versus reversible hydrogen electrode in 0.1 M KHCO3 and remarkable C2 H4 and C2+ FEs of 82% and 91.7% in a flow cell at a current density of 400 mA cm-2 in 1 M KOH. In situ characterizations and theoretical calculations reveal that the active interfaces facilitate CO2 activation and lower the formation energy of the key intermediate *OCCOH, thus promoting CO2 conversion to C2+ . This work provides a rational design for steering the active sites toward C2+ products.

11.
Biomed Pharmacother ; 165: 115191, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37487440

RESUMO

ß-hydroxybutyrate (ß-HB), the most abundant ketone body, is produced primarily in the liver and acts as a substitute energy fuel to provide energy to extrahepatic tissues in the event of hypoglycemia or glycogen depletion. We now have an improved understanding of ß-HB as a signal molecule and epigenetic regulatory factor as a result of intensive research over the last ten years. Because ß-HB regulates various physiological and pathological processes, it may have a potential role in the treatment of metabolic diseases. The liver is the most significant metabolic organ, and the part that ß-HB plays in liver disorders is receiving increasing attention. In this review, we summarize the therapeutic effects of ß-HB on liver diseases and its underlying mechanisms of action. Moreover, we explore the prospects of exogenous supplements and endogenous ketosis including fasting, caloric restriction (CR), ketogenic diet (KD), and exercise as adjuvant nutritional therapies to protect the liver from damage and provide insights and strategies for exploring the treatment of various liver diseases.


Assuntos
Dieta Cetogênica , Cetose , Hepatopatias , Humanos , Ácido 3-Hidroxibutírico/metabolismo , Corpos Cetônicos/metabolismo , Hepatopatias/tratamento farmacológico
12.
Am J Transl Res ; 15(5): 3342-3354, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37303656

RESUMO

Owing to the symbiotic relationship between the microbiota and the human body, the microbiome is considered a "second human genome". Microorganisms are inextricably associated with human diseases and can affect the host phenotype. In the present study, 25 female patients with stage 5 chronic kidney disease (CKD5) undergoing hemodialysis in our hospital and 25 healthy subjects were recruited. The structure of the oral microbiota of the study participants was analyzed using the MiSeq PE300 sequencing platform and high-throughput 16S rDNA sequencing. The microbiota was compared between the groups using QIIME and the stats package in R. In total, 1,336 operational taxonomic units (OTUs) were obtained, and the relative frequencies of 450 OTUs differed significantly between the two groups (P < 0.05), indicating that the samples were rich in OTUs. A comparison of ß-diversity indicated a significant difference in the microbial community structure between the two groups (P < 0.05). These results indicated that the biological diversity of the oral microbiota was highly correlated with CKD5. In this experiment, 189 genera, with significant differences in abundance between the groups (P < 0.05), were found. Furthermore, differences in the structure of the oral microbiota were observed between the groups at the phylum, class, order, family, and genus levels. Collectively, an imbalance in the oral microbiota may accelerate the progression of CKD and cause additional complications.

13.
J Agric Food Chem ; 71(20): 7669-7678, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37159413

RESUMO

Cadmium (Cd) pollution reduces rice production and quality, putting food security and human health at risk. We conducted comparative physiology and metabolomic analyses in two indica rice ('NH199' and 'NH224') to elucidate the Cd-tolerance mechanism. Cd hampered rice growth, induced oxidative stress, and changed the metabolomics profiling of the root. The biochemical and physiological analysis demonstrated that NH224 exhibited a more potent Cd-tolerance ability than NH199. Cd was primarily distributed in root, and NH224 had a lower Cd translocation factor than NH199 by about 24%. The metabolomic analysis revealed 180 and 177 differentially accumulated metabolites between Cd-stressed seedlings and the controls in NH224 and NH199, respectively. In NH224, amino acids biosynthesis, hormone metabolism, lipids-related metabolism, phenylalanine metabolism, and phenylpropanoid biosynthesis pathways were more active and highly associated with antioxidant defense system, biosynthesis of the cell wall and phytochelatins, and maintenance of plasma membrane stability. These findings provide insights into the metabolic profiles of rice following Cd stress and the screening and breeding of Cd-tolerant rice varieties.


Assuntos
Oryza , Poluentes do Solo , Humanos , Oryza/metabolismo , Cádmio/metabolismo , Raízes de Plantas/metabolismo , Melhoramento Vegetal , Antioxidantes/metabolismo , Plântula , Poluentes do Solo/metabolismo
14.
Angew Chem Int Ed Engl ; 62(22): e202217449, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-36959732

RESUMO

Nickel-based catalysts have been regarded as one of the most promising electrocatalysts for urea oxidation reaction (UOR), however, their activity is largely limited by the inevitable self-oxidation reaction of Ni species (NSOR) during the UOR. Here, we proposed an interface chemistry modulation strategy to trigger the occurrence of UOR before the NSOR via constructing a 2D/2D heterostructure that consists of ultrathin NiO anchored Ru-Co dual-atom support (Ru-Co DAS/NiO). Operando spectroscopic characterizations confirm this unique triggering mechanism on the surface of Ru-Co DAS/NiO. Consequently, the fabricated catalyst exhibits outstanding UOR activity with a low potential of 1.288 V at 10 mA cm-2 and remarkable long-term durability for more than 330 h operation. DFT calculations and spectroscopic characterizations demonstrate that the favorable electronic structure induced by this unique heterointerface endows the catalyst energetically more favorable for the UOR than the NSOR.

15.
Adv Mater ; 35(25): e2209954, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36780880

RESUMO

2D transition metal carbides (2D TMCs and MXenes) are promising candidates for applications of energy storage and catalysis. However, producing high-quality, large 2D flakes of Mo2C MXene has been challenging. Here, a new salt-assisted templating approach is reported that enables the direct synthesis of 2D Mo2 C with low defect concentrations. KCl acts as a template to form an intermediate 2D product, facilitating Mo2 C formation without coarsening upon melting. The thickness of the flakes produced can range from monolayer (0.36 nm) to 10 layers (4.55 nm), and the electrocatalytical hydrogen evolution reaction (HER) activity of 2D Mo2 C is inversely proportional to its thickness. The monolayer Mo2 C shows remarkable HER performance with a current density of ≈6800 mA cm- 2 at 470 mV versus reversible hydrogen electrode and an ultrahigh turnover frequency of ≈17 500 s- 1 . This salt-assisted synthesis approach can also produce WC and V8 C7 nanosheets, expanding the family of 2D carbides. The new pathway eliminates the need for layered ceramic precursors, making it a versatile approach to direct synthesis of MXene-like 2D carbides.

16.
Sci Total Environ ; 866: 161373, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36621472

RESUMO

N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPDQ), one of the oxidation products of rubber antioxidant 6PPD, has been identified as a novel toxicant to many organisms. However, an understanding of its underlying toxicity mechanisms remained elusive. In this study, we reported that 6PPDQ could react with deoxyguanosine to form one isomer of 3-hydroxy-1, N2-6PPD-etheno-2'-deoxyguanosine (6PPDQ-dG). Next, by employing an ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method, we found that 6PPDQ-dG could be detected in genomic DNA from 6PPDQ-treated mammalian cells and Chlamydomonas reinhardtii. We observed positive correlations between concentrations of exogenous 6PPDQ and the amounts of 6PPDQ-dG, and a recovery period after removal of 6PPDQ also led to decreased levels of the adduct in both organisms, which suggested potential repair pathways for this adduct in mammalian cells and unicellular algae. Additionally, we extracted the genomic DNA from tissues of frozen capelin and observed substantial amounts of the adduct in roe and gills, as well as livers at a relatively lower level. These results provided insights into the target organs and tissues that 6PPDQ might accumulate or harm fish. Overall, our study provides a new understanding of the mechanisms of toxicity of 6PPDQ in mammalian cells and aqueous organisms.


Assuntos
Antioxidantes , Benzoquinonas , Chlamydomonas reinhardtii , Adutos de DNA , Fenilenodiaminas , Cromatografia Líquida de Alta Pressão , Desoxiguanosina/química , Adutos de DNA/metabolismo , Quinonas , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Fenilenodiaminas/química , Fenilenodiaminas/metabolismo , Fenilenodiaminas/toxicidade , Benzoquinonas/química , Benzoquinonas/metabolismo , Benzoquinonas/toxicidade , Antioxidantes/química , Antioxidantes/metabolismo , Antioxidantes/toxicidade , Chlamydomonas reinhardtii/efeitos dos fármacos , Chlamydomonas reinhardtii/genética , Chlamydomonas reinhardtii/metabolismo , Humanos , Células A549
17.
J Hazard Mater ; 443(Pt A): 130124, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36308928

RESUMO

Plasmonic nanoparticles that self-assemble into highly ordered superlattice nanostructures hold substantial promise for facilitating ultra-trace surface-enhanced Raman scattering (SERS) detection. Herein, we propose a boiling-point evaporation method to synthesize ordered monocrystal-like superlattice Au nanostructures (OML-Au NTs) with a polyhedral morphology. Combined with thermal nanoimprint technology, OML-Au NTs were directly transferred to impact-resistant polystyrene (IPS) flexible SERS substrates, the obtained flexible substrates (donated as OML-Au NTs/IPS) detection limit for R6G molecules as low as 10-13 M. These results were confirmed by simulating the electromagnetic field distribution of ordered/unordered two-dimensional single-layer and three-dimensional aggregated gold nanostructures. The OML-Au NTs/IPS substrates were successfully used to detect and quantify three commonly-used agricultural pesticides, achieving detection limits as low as 10-11 M and 10-12 M, and in situ real-time detection limit reached 0.24 pg/cm2 for thiram on apple peels, which was 3 orders of magnitude lower than the current detection limit. In addition, the Raman intensity from multiple locations showed a relative standard deviation lower than 7 %, exhibiting the reliability necessary for practical applications. As a result, this research demonstrates a highly reproducible method to enable the development of plasmonic nanomaterials with flexible superstructures.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Ouro/química , Análise Espectral Raman/métodos , Nanoestruturas/química
18.
Accid Anal Prev ; 180: 106907, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36455450

RESUMO

Lane-changing trajectory planning (LTP) is an effective concept to control automated vehicles (AVs) in mixed traffic, which can reduce traffic conflicts and improve overall traffic efficiency. To enhance the lane change safety for AVs, a co-evolutionary lane-changing trajectory planning (CLTP) method is proposed to describe the risk minimization process that co-evolves with the dynamic traffic environment in the limited literature. Firstly, the natural driving data of vehicle trajectory on the expressway provided by the High dataset are used to construct the lane-changing samples. To obtain the future traffic environment information, a deep learning neural network is adopted to capture trajectory dynamics in mobility of surrounding vehicles around a lane-changing vehicle. Secondly, the safe interaction between the subject vehicle and the surrounding vehicles is considered to establish a mathematical model for the temporal and spatial risk identification of a lane change event based on the fault tree analysis method. Subsequently, the risk minimization of lane change is considered as the objective. Based on the acceleration and deceleration overtaking rules and the trapezoidal acceleration method, the longitudinal and lateral displacement schemes during a lane change are designed. Finally, the motion parameters of longitudinal and lateral displacement are acquired to form an ideal lane change trajectory using a genetic algorithm. The results show that this method can effectively achieve higher safety of the lane-changing process, and reduce the traffic conflicts and traffic turbulence caused by dangerous lane-changing behaviors. The findings can provide theoretical support for lane change trajectory planning algorithm design of intelligent vehicles.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Humanos , Acidentes de Trânsito/prevenção & controle , Veículos Autônomos , Algoritmos , Aceleração
19.
Artigo em Inglês | MEDLINE | ID: mdl-36586340

RESUMO

The exact levels of some DNA adducts, like N7-deoxyguanosine (N7-dG), can be under-calculated since these adducts may depurinate due to their chemical instability, leading to corresponding nucleobase adducts being released into the cytoplasm. To accurately quantify the levels of DNA adducts, it is necessary to consider those modified nucleobases. However, high levels and diversity of cytoplasmic small molecule metabolites (SMMs) can strongly interfere with the detection of adducts, and it is almost impossible to remove them with nucleobase adducts being well retained. Therefore, we aimed to establish an optimized enrichment method based on solid-phase extraction (SPE) to reduce the co-elution of SMMs with target analytes. In this vein, we employed three bisphenols (BPA, BPF, and BPAF) as examples, prepared corresponding N7-guanine (N7-Gua) adducts, loaded on an Oasis hydrophilic-lipophilic balance ® (HLB) cartridge, used a series of mobile phases containing different percentage of methanol for elution, and evaluated the levels of these adducts in each eluent. First, we found that neutral samples led to the best retention for all three adducts compared with acidified or basified ones. We next employed normal distribution fitting model to characterize the elution of analytes from H2O/methanol with different pHs and observed that neutral mobile phases resulted in more hydrophobic elution for all three adducts. Besides, N7-BPA-Gua and N7-BPF-Gua obtained narrow fitted peaks at neutral pH, while N7-BPAF-Gua had minimized elution windows at low pH. After optimization, we exposed 293T cells to the aforementioned bisphenols and quantified the N7-Gua adducts in the cytoplasm and the corresponding N7-dG adducts in genomic DNA. The results revealed that with the same levels of BPs exposure, BPAF led to the highest levels of adducts in both cytoplasm and genomic DNA samples, followed by BPA and BPF in order. In summary, our research established an appropriate model to describe the elution of DNA adducts in the SPE, applied it to optimize the loading and elution conditions, and discussed the genotoxicity of bisphenols by accurate quantification of both cleaved and uncleaved N7-dG adducts.


Assuntos
Adutos de DNA , Metanol , DNA/química , Guanina/química , Indicadores e Reagentes , Citoplasma/metabolismo , Extração em Fase Sólida , Genômica
20.
Acta Radiol ; : 2841851221142783, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36503262

RESUMO

BACKGROUND: Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a rare autoimmune disease characterized by skin or osteoarticular damage. SAPHO syndrome is often misdiagnosed or missed diagnosis due to lack of overall understanding of the disease by clinicians. PURPOSE: To analyze the clinical symptoms and imaging features of six Han patients with SAPHO syndrome in order to provide reference for doctors to diagnose SAPHO syndrome. MATERIAL AND METHODS: This study retrospectively analyzed the clinical data of six Han patients with SAPHO syndrome. RESULTS: All six Han patients with SAPHO syndrome had severe acne or pustulosis of the hands and feet, and all of them had osteoarticular damage, including five cases involving the sternoclavicular joint. Some patients showed a specific and typical "bull's head" sign on 99mTc-labeled methylene diphosphonate bone imaging. Among the six patients recruited, there was one thoracic vertebra, one cervical vertebra, one sacroiliac joint, and one peripheral joint involvement. Two patients had limited activity due to severe osteoarticular damage. CONCLUSION: Due to the atypical clinical symptoms of SAPHO syndrome, most patients will experience a tortuous and long diagnostic process, while a correct understanding and timely intervention of SAPHO syndrome are essential to improve the prognosis of patients.

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