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1.
FASEB J ; 38(8): e23590, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38656553

RESUMO

Studies have suggested that microglial IL-6 modulates inflammatory pain; however, the exact mechanism of action remains unclear. We therefore hypothesized that PKCε and MEG2 competitively bind to STAT3 and contribute to IL-6-mediated microglial hyperalgesia during inflammatory pain. Freund's complete adjuvant (FCA) and lipopolysaccharide (LPS) were used to induce hyperalgesia model mice and microglial inflammation. Mechanical allodynia was evaluated using von Frey tests in vivo. The interaction among PKCε, MEG2, and STAT3 was determined using ELISA and immunoprecipitation assay in vitro. The PKCε, MEG2, t-STAT3, pSTAT3Tyr705, pSTAT3Ser727, IL-6, GLUT3, and TREM2 were assessed by Western blot. IL-6 promoter activity and IL-6 concentration were examined using dual luciferase assays and ELISA. Overexpression of PKCε and MEG2 promoted and attenuated inflammatory pain, accompanied by an increase and decrease in IL-6 expression, respectively. PKCε displayed a stronger binding ability to STAT3 when competing with MEG2. STAT3Ser727 phosphorylation increased STAT3 interaction with both PKCε and MEG2. Moreover, LPS increased PKCε, MEG2, pSTAT3Tyr705, pSTAT3Ser727, IL-6, and GLUT3 levels and decreased TREM2 during microglia inflammation. IL-6 promoter activity was enhanced or inhibited by PKCε or MEG2 in the presence of STAT3 and LPS stimulation, respectively. In microglia, overexpression of PKCε and/or MEG2 resulted in the elevation of tSTAT3, pSTAT3Tyr705, pSTAT3Ser727, IL-6, and TREM2, and the reduction of GLUT3. PKCε is more potent than MEG2 when competitively binding to STAT3, displaying dual modulatory effects of IL-6 production, thus regulating the GLUT3 and TREM2 in microglia during inflammatory pain sensation.


Assuntos
Hiperalgesia , Inflamação , Interleucina-6 , Microglia , Proteína Quinase C-épsilon , Fator de Transcrição STAT3 , Animais , Masculino , Camundongos , Adjuvante de Freund , Hiperalgesia/metabolismo , Inflamação/metabolismo , Interleucina-6/metabolismo , Interleucina-6/genética , Lipopolissacarídeos/toxicidade , Lipopolissacarídeos/farmacologia , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Dor/metabolismo , Fosforilação , Ligação Proteica , Proteína Quinase C-épsilon/metabolismo , Proteína Quinase C-épsilon/genética , Receptores Imunológicos/metabolismo , Receptores Imunológicos/genética , Fator de Transcrição STAT3/metabolismo , Proteínas Tirosina Fosfatases não Receptoras/metabolismo
2.
Environ Sci Technol ; 58(11): 5129-5138, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38385684

RESUMO

Attention has been drawn to the associations between PFASs and human cognitive decline. However, knowledge on the occurrence and permeability of PFASs in the brains of patients with cognitive impairment has not been reported. Here, we determined 30 PFASs in paired sera and cerebrospinal fluids (CSFs) from patients with cognitive impairment (n = 41) and controls without cognitive decline (n = 18). We revealed similar serum PFAS levels but different CSF PFAS levels, with lower CSF PFOA (median: 0.125 vs 0.303 ng/mL, p < 0.05), yet higher CSF PFOS (0.100 vs 0.052 ng/mL, p < 0.05) in patients than in controls. Blood-brain transfer rates also showed lower RCSF/Serum values for PFOA and higher RCSF/Serum values for PFOS in patients, implying potential heterogeneous associations with cognitive function. The RCSF/Serum values for C4-C14 perfluoroalkyl carboxylates exhibited a U-shape trend with increasing chain length. Logistic regression analyses demonstrated that CSF PFOS levels were linked to the heightened risk of cognitive impairment [odds ratio: 3.22 (1.18-11.8)] but not for serum PFOS. Toxicity inference results based on the Comparative Toxicogenomics Database suggested that PFOS in CSF may have a greater potential to impair human cognition than other PFASs. Our results contribute to a better understanding of brain PFAS exposure and its potential impact on cognitive function.


Assuntos
Ácidos Alcanossulfônicos , Disfunção Cognitiva , Poluentes Ambientais , Fluorocarbonos , Humanos , Ácidos Alcanossulfônicos/toxicidade , Fluorocarbonos/toxicidade , Ácidos Carboxílicos , Permeabilidade
3.
Environ Res ; 251(Pt 2): 118692, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38493856

RESUMO

Overloading of nutrients such as nitrogen causes eutrophication of freshwater bodies. The spread of antibiotic resistance genes (ARGs) poses a threat to ecosystems. However, studies on the enrichment and spread of ARGs from increased nitrogen loading in algal-bacterial symbiotic systems are limited. In this study, the transfer of extracellular kanamycin resistance (KR) genes from large (RP4) small (pEASY-T1) plasmids into the intracellular and extracellular DNA (iDNA, eDNA) of the inter-algal environment of Chlorella pyrenoidosa was investigated, along with the community structure of free-living (FL) and particle-attached (PA) bacteria under different nitrogen source concentrations (0-2.5 g/L KNO3). The results showed that KR gene abundance in the eDNA adsorbed on solid particles (D-eDNA) increased initially and then decreased with increasing nitrogen concentration, while the opposite was true for the rest of the free eDNA (E-eDNA). Medium nitrogen concentrations promoted the transfer of extracellular KR genes into the iDNA attached to algal microorganisms (A-iDNA), eDNA attached to algae (B-eDNA), and the iDNA of free microorganisms (C-iDNA); high nitrogen contributed to the transfer of KR genes into C-iDNA. The highest percentage of KR genes was found in B-eDNA with RP4 plasmid treatment (66.2%) and in C-iDNA with pEASY-T1 plasmid treatment (86.88%). In addition, dissolved oxygen (DO) significantly affected the bacterial PA and FL community compositions. Nephelometric turbidity units (NTU) reflected the abundance of ARGs in algae. Proteobacteria, Cyanobacteria, Bacteroidota, and Actinobacteriota were the main potential hosts of ARGs. These findings provide new insights into the distribution and dispersal of ARGs in the phytoplankton inter-algal environment.


Assuntos
Bactérias , Resistência Microbiana a Medicamentos , Eutrofização , Transferência Genética Horizontal , Microalgas , Simbiose , Microalgas/genética , Microalgas/efeitos dos fármacos , Bactérias/genética , Bactérias/efeitos dos fármacos , Resistência Microbiana a Medicamentos/genética , Chlorella/genética , Chlorella/efeitos dos fármacos , Nitrogênio
4.
BMC Pulm Med ; 24(1): 324, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965571

RESUMO

BACKGROUND: The advent of immunotherapy targeting immune checkpoints has conferred significant clinical advantages to patients with lung adenocarcinoma (LUAD); However, only a limited subset of patients exhibit responsiveness to this treatment. Consequently, there is an imperative need to stratify LUAD patients based on their response to immunotherapy and enhance the therapeutic efficacy of these treatments. METHODS: The differentially co-expressed genes associated with CD8 + T cells were identified through weighted gene co-expression network analysis (WGCNA) and the Search Tool for the Retrieval of Interacting Genes (STRING) database. These gene signatures facilitated consensus clustering for TCGA-LUAD and GEO cohorts, categorizing them into distinct immune subtypes (C1, C2, C3, and C4). The Tumor Immune Dysfunction and Exclusion (TIDE) model and Immunophenoscore (IPS) analysis were employed to assess the immunotherapy response of these subtypes. Additionally, the impact of inhibitors targeting five hub genes on the interaction between CD8 + T cells and LUAD cells was evaluated using CCK8 and EDU assays. To ascertain the effects of these inhibitors on immune checkpoint genes and the cytotoxicity mediated by CD8 + T cells, flow cytometry, qPCR, and ELISA methods were utilized. RESULTS: Among the identified immune subtypes, subtypes C1 and C3 were characterized by an abundance of immune components and enhanced immunogenicity. Notably, both C1 and C3 exhibited higher T cell dysfunction scores and elevated expression of immune checkpoint genes. Multi-cohort analysis of Lung Adenocarcinoma (LUAD) suggested that these subtypes might elicit superior responses to immunotherapy and chemotherapy. In vitro experiments involved co-culturing LUAD cells with CD8 + T cells and implementing the inhibition of five pivotal genes to assess their function. The inhibition of these genes mitigated the immunosuppression on CD8 + T cells, reduced the levels of PD1 and PD-L1, and promoted the secretion of IFN-γ and IL-2. CONCLUSIONS: Collectively, this study delineated LUAD into four distinct subtypes and identified five hub genes correlated with CD8 + T cell activity. It lays the groundwork for refining personalized therapy and immunotherapy strategies for patients with LUAD.


Assuntos
Adenocarcinoma de Pulmão , Linfócitos T CD8-Positivos , Neoplasias Pulmonares , Humanos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/imunologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Linfócitos T CD8-Positivos/imunologia , Imunoterapia , Regulação Neoplásica da Expressão Gênica , Perfilação da Expressão Gênica , Linhagem Celular Tumoral
5.
Angew Chem Int Ed Engl ; : e202405396, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38818672

RESUMO

Reactive oxygen species (ROS) play a crucial role in determining photocatalytic reaction pathways, intermediate species, and product selectivity. However, research on ROS regulation in polymer photocatalysts is still in its early stages. Herein, we successfully achieved series of modulations to the skeleton of Pyrene-alkyne-based (Tetraethynylpyrene (TEPY)) conjugated porous polymers (CPPs) by altering the linkers (1,4-dibromobenzene (BE), 4,4'-dibromobiphenyl (IP), and 3,3'-dibromobiphenyl (BP)). Experiments combined with theoretical calculations indicate that BE-TEPY exhibits a planar structure with minimal exciton binding energy, which favors exciton dissociation followed by charge transfer with adsorbed O2 to produce ⋅O2 -. Thus BE-TEPY shows optimal photocatalytic activity for phenylboronic acid oxidation and [3+2] cycloaddition. Conversely, the skeleton of BP-TEPY is significantly distorted. Its planar conjugation decreases, intersystem crossing (ISC) efficiency increases, which makes it more prone for resonance energy transfer to generate 1O2. Therefore, BP-TEPY displays best photocatalytic activity in [4+2] cycloaddition and thioanisole oxidation. Both above reactant conversion and its product selectivity exceed 99 %. This work systematically reveals the intrinsic structure-activity relationship among the skeleton structure of CPPs, excitonic behavior, and selective generation of ROS, providing new insights for the rational design of highly efficient and selective CPPs photocatalysts.

6.
Clin Immunol ; 255: 109734, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37572951

RESUMO

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is a newly defined inflammatory demyelinating disease of the central nervous system. Currently, no immuno-modulatory treatment has been approved for MOGAD. We explored the function of follicular regularoty T (Tfr) and follicular helper T (Tfh) cells in patients with MOGAD. The number of circulating Tfr and Tfh cells and their expression of functional markers were accessed by flow cytometry. Circulating Tfr, Tfh, and B cells were further sorted and co-cultured in vitro to examine the influence of Tfr on Tfh-mediated B cell differentiation. In patients with MOGAD, the percentage of circulating PD-1hi Tfh cells elevated while the frequency of circulating activated Tfr cells decreased significantly. The Tfh/Tfr ratios positively correlated with the percentage of plasmblasts. In vitro, Tfh cells from patients with MOGAD exhibited a stronger capacity to promote the differentiation of plasmablasts through producing interleukin (IL)-21 than non-Tfh cells from patients, whereas Tfr cells suppressed this Tfh-mediated plasmablasts expansion, to a similar extent of IL-1 receptor antagonist (IL-1Ra). In conclusion, we revealed an immune imbalance of Tfr and Tfh cells in MOGAD. Tfr and IL-1Ra could be potential therapeutic targets in MOGAD.


Assuntos
Proteína Antagonista do Receptor de Interleucina 1 , Linfócitos T Auxiliares-Indutores , Humanos , Glicoproteína Mielina-Oligodendrócito , Linfócitos B , Linfócitos T Reguladores , Imunoglobulina G/metabolismo
7.
Neurol Sci ; 44(3): 835-843, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36301362

RESUMO

OBJECTIVE: Lipid abnormalities are important risk factors in patients with large atherosclerotic strokes. Recent studies have shown that non-traditional lipid parameters are crucial to the development of atherosclerosis and are closely related to the clinical outcome of acute ischemic stroke (AIS). Therefore, we aimed to investigate the relationship between non-traditional lipid parameters and carotid plaque stability and stenosis degree in patients with large atherosclerotic stroke. METHODS: We retrospectively analyzed 336 patients with AIS. All patients were divided into the non-plaque group, stable plaque group, and vulnerable plaque group according to ultrasound examination. At the same time, the patients were divided into non-stenosis, mild stenosis, moderate stenosis, and severe stenosis groups according to the degree of stenosis. Non-traditional lipid parameters, including residual lipoprotein cholesterol (RLP-C), non-high-density lipoprotein cholesterol (non-HDL-C), non-HDL-C to high-density lipoprotein cholesterol ratio (non-HDL-C/HDL-C), triglyceride to HDL-C ratio (TG/HDL-C), Castelli's risk index (CRI), and the atherogenic index of plasma (AIP). Receiver operating characteristic (ROC) curves and multivariate logistic regression analyses were used to investigate the associations between the non-traditional lipid parameters and carotid plaque vulnerability. Spearman linear correlation analysis was used to test the correlation between variables and the degree of carotid plaque stenosis. RESULTS: This study population included 336 patients with AIS, of whom 294 had a carotid plaque. Multivariate logistic regression model showed that RLP-C (OR, 3.361; 95%CI, 1.311-8.617), non-HDL-C/HDL-C (OR, 1.699; 95%CI, 1.279-2.258), non-HDL-C (OR, 1.704; 95%CI, 1.143-2.540), CRI-I (OR, 1.573; 95%CI, 1.196-2.068), and CRI-II (OR, 2.022; 95%CI, 1.369-2.985) were independent risk factors for carotid plaque vulnerability. In addition, Spearman correlation analysis showed that the values of RLP-C, non-HDL-C/HDL-C, non-HDL-C, TG/HDL-C, CRI-I, CRI-II, and AIP on admission were positively correlated with the degree of carotid plaque stenosis (all P < 0.001). CONCLUSION: This study provides evidence that non-traditional lipid parameters (LP-C, non-HDL-C/HDL-C, non-HDL-C, CRI-I, and CRI-II) were potential predictors of carotid plaque vulnerability in patients with AIS. However, no significant correlation was observed between TG/HDL-C and AIP. RLP-C, non-HDL-C/HDL-C, non-HDL-C, TG/HDL-C, CRI-I, CRI-II, and AIP were closely related to the degree of carotid plaque stenosis. Non-traditional lipid parameters can be used as novel biomarkers of carotid plaque vulnerability and stenosis.


Assuntos
Aterosclerose , Estenose das Carótidas , AVC Isquêmico , Placa Aterosclerótica , Humanos , Estudos Retrospectivos , AVC Isquêmico/etiologia , AVC Isquêmico/complicações , Placa Aterosclerótica/complicações , Placa Aterosclerótica/diagnóstico por imagem , Artérias Carótidas , Fatores de Risco , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Constrição Patológica
8.
Clin Oral Investig ; 27(3): 1089-1100, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36048254

RESUMO

OBJECTIVES: Soft tissue phenotype modification (STPM) could be performed to maintain peri-implant health. Therefore, the aim of the study was to analyze tissue alteration around implants following soft tissue phenotype modification during implant uncovering surgery. MATERIALS AND METHODS: Patients who had STPM (either pouch roll or modified roll technique) during implant second-stage surgery with at least 12-month follow-up were included. Clinical and radiographic parameters including mucosal tissue thickness (MTT), recession (REC), keratinized mucosa width (KMW), probing pocket depth (PPD), marginal bone loss (MBL), emergence profile, and emergence angle were extracted from 2-week, 2-month, and 12-month visits after second-stage surgery. RESULTS: Twenty-eight patients with 33 implants that fulfilled the inclusion criteria were included. After soft tissue phenotype modification, at 2 weeks, REC was negatively correlated to mean MTT at mid-buccal site (r = - 0.41, p = 0.018) and borderline correlated at mid-lingual site (r = - 0.343, p = 0.051). Stable KMW was maintained from 2 weeks to 12 months with minimal shrinkage rate (3 ~ 14%). MBL change was limited (0.24 ~ 0.47 mm) after STPM. All implants had shallow PPD (≤ 3 mm) with the absence of bleeding on probing. Emergence angle at the mesial side, however, was significantly correlated to surgical techniques, which indicated pouch roll technique would have 6.96 degrees more than modified roll technique (p = 0.024). CONCLUSIONS: Soft tissue phenotype modification, either pouch roll or modified roll technique, during uncovering surgery resulted in favorable clinical outcomes. Thin mucosal tissue thickness and pouch roll technique are the factors related to more recession at 2 weeks. Pouch roll technique could influence the restorative design by having a wide emergence angle at the mesial side. CLINICAL RELEVANCE: Modified and pouch roll techniques during uncovering surgery were viable methods to yield favorable peri-implant health, while the preciseness of pouch roll technique was required to avoid mucosal recession and inadequate restorative design.


Assuntos
Implantes Dentários , Estudos de Coortes , Mucosa
9.
Sensors (Basel) ; 23(24)2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38139566

RESUMO

An accurate estimation of the time difference of arrival (TDOA) is crucial in localization, communication, and navigation. However, a low signal-to-noise ratio (SNR) can decrease the reliability of the TDOA estimation result. Therefore, this study aims to improve the performance of the TDOA estimation of dual-channel sensors for single-sound sources in low-SNR environments. This study introduces the theory of time rearrangement synchrosqueezing transform (TRST) into the time difference of arrival estimation. While the background noise TF points show random time delays, the signal time-frequency (TF) points originating from uniform directions that exhibit identical lags are considered in this study. In addition, the time difference rearrangement synchrosqueezing transform (TDST) algorithm is developed to separate the signal from the background noise by exploiting its distinct time delay characteristics. The implementation process of the proposed algorithm includes four main steps. First, a rough estimation of the time delay is performed by calculating the partial derivative of the short-time cross-power spectrum. Second, a rearrangement operation is conducted to separate the TF points of the signal and noise. Third, the TF points on both sides of the time-delay energy ridge are extracted. Finally, a refined TDOA estimation is realized by applying the inverse Fourier transformation on the extracted TF points. Furthermore, a second-order-based time difference reassigned synchrosqueezing transform algorithm is proposed to improve the robustness of the TDOA estimation by enhancing the TF energy aggregation. The proposed algorithms are verified by simulations and experiments. The results show that the proposed algorithms are more robust and accurate than the existing algorithms.

10.
Sensors (Basel) ; 23(20)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37896441

RESUMO

Recent advances in roller coasters accelerate the creation of complex tracks to provide stimulation and excitement for humans. As the main load-bearing component, tracks are prone to damage such as loose connecting bolts, paint peeling, corroded sleeper welds, corroded butt welds, reduced track wall thickness and surface cracks under complex environments and long-term alternating loads. However, inspection of the roller coaster tracks, especially the high-altitude rolling tracks, is a crucial problem that traditional manual detection methods have difficulty solving. In addition, traditional inspection is labor-intensive, time-consuming, and provides only discrete information. Here, a concept of the multifunctional detection robot with a mechanical structure, electrical control system, camera, electromagnetic ultrasonic probes and an array of eddy current probes for detecting large roller coaster tracks is reported. By optimizing the design layout, integrating multiple systems and completing machine testing, the multifunctional roller coaster track detection robot exhibits outstanding performance in track appearance, thickness and crack detection. This study provides great potential for intelligent detection in amusement equipment, railcar, train and so on.

11.
Int J Mol Sci ; 24(22)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38003525

RESUMO

Pepper (Capsicum annuum L.) is sensitive to low temperatures, with low-temperature stress affecting its plant growth, yield, and quality. In this study, we analyzed the effects of exogenous hydrogen sulfide (H2S) on pepper seedlings subjected to low-temperature stress. Exogenous H2S increased the content of endogenous H2S and its synthetase activity, enhanced the antioxidant capacity of membrane lipids, and protected the integrity of the membrane system. Exogenous H2S also promoted the Calvin cycle to protect the integrity of photosynthetic organs; enhanced the photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), and photosynthesis; and reduced the intercellular CO2 concentration (Ci). Moreover, the activities of superoxide dismutase, peroxidase, catalase, and anti-cyclic glutathione (ASA-GSH) oxidase were improved to decompose excess reactive oxygen species (ROS), enhance the oxidative stress and detoxification ability of pepper seedlings, and improve the resistance to low-temperature chilling injury in 'Long Yun2' pepper seedlings. In addition, the H2S scavenger hypotaurine (HT) aggravated the ROS imbalance by reducing the endogenous H2S content, partially eliminating the beneficial effects of H2S on the oxidative stress and antioxidant defense system, indicating that H2S can effectively alleviate the damage of low temperature on pepper seedlings. The results of transcriptome analysis showed that H2S could induce the MAPK-signaling pathway and plant hormone signal transduction; upregulate the expression of transcription factors WRKY22 and PTI6; induce defense genes; and activate the ethylene and gibberellin synthesis receptors ERF1, GDI2, and DELLA, enhancing the resistance to low-temperature chilling injury of pepper seedlings. The plant-pathogen interaction was also significantly enriched, suggesting that exogenous H2S also promotes the expression of genes related to plant-pathogen interaction. The results of this study provide novel insights into the molecular mechanisms and genetic modifications of H2S that mitigate the hypothermic response.


Assuntos
Sulfeto de Hidrogênio , Sulfeto de Hidrogênio/farmacologia , Sulfeto de Hidrogênio/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Temperatura , Plântula/genética , Espécies Reativas de Oxigênio/metabolismo , Glutationa/metabolismo
12.
Mol Microbiol ; 115(4): 739-757, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33155333

RESUMO

Both isomeric forms of alanine play a crucial role in bacterial growth and viability; the L-isomer of this amino acid is one of the building blocks for protein synthesis, and the D-isomer is incorporated into the bacterial cell wall. Despite a long history of genetic manipulation of Bacillus subtilis using auxotrophic markers, the genes involved in alanine metabolism have not been characterized fully. In this work, we genetically characterized the major enzymes involved in B. subtilis alanine biosynthesis and identified an alanine permease, AlaP (YtnA), which we show has a major role in the assimilation of D-alanine from the environment. Our results provide explanations for the puzzling fact that growth of B. subtilis does not result in the significant accumulation of extracellular D-alanine. Interestingly, we find that in B. subtilis, unlike E. coli where multiple enzymes have a biochemical activity that can generate alanine, the primary synthetic enzyme for alanine is encoded by alaT, although a second gene, dat, can support slow growth of an L-alanine auxotroph. However, our results also show that Dat mediates the synthesis of D-alanine and its activity is influenced by the abundance of L-alanine. This work provides valuable insights into alanine metabolism that suggests that the relative abundance of D- and L-alanine might be linked with cytosolic pool of D and L-glutamate, thereby coupling protein and cell envelope synthesis with the metabolic status of the cell. The results also suggest that, although some of the purified enzymes involved in alanine biosynthesis have been shown to catalyze reversible reactions in vitro, most of them function unidirectionally in vivo.


Assuntos
Alanina/metabolismo , Sistemas de Transporte de Aminoácidos/genética , Sistemas de Transporte de Aminoácidos/metabolismo , Bacillus subtilis/fisiologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Transaminases/metabolismo , Bacillus subtilis/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Vias Biossintéticas
13.
Opt Express ; 30(22): 40991-41001, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36299022

RESUMO

In this paper, we demonstrate an adaptive liquid lens with a tunable field of view (FOV). The proposed liquid lens consists of an actuator and a lens chamber, the annular sheet is just placed on the liquid-liquid (L-L) interface in order to change the curvature and steer the tilt angle of the interface. Different from the conventional FOV adjustable lens combined with a liquid lens and a liquid prism, the proposed lens requires only one L-L interface to achieve the focal length change and FOV deflection. Moreover, the proposed lens reduces aberrations while maintaining high resolution. The experiments show that the optical power range is -27 m-1 to 30 m-1. It can realize the FOV deflection while tuning the focal length, with an angular resolution of 37"05. The proposed lens can be applied to telescopic system and microscopic system.

14.
Chemistry ; 28(25): e202200666, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35262970

RESUMO

The germylene species (CH{(CMe)(2,6-iPr2 C6 H3 N)}2 )GePCO 1 is shown to react with the Lewis acids (E(C6 F5 )3 E=B, Al). Nonetheless, 1 participates in FLP chemistry with electron deficient alkynes or olefins, acting as an intramolecular FLP. In contrast, in the presence of B(C6 F5 )3 and an electron rich alkyne, 1 behaves as Ge-based nucleophile to effect intermolecular FLP addition to the alkyne. This reactivity demonstrates that the reaction pathway is controlled by the nature of the electrophile and nucleophile generated in solution, as revealed by extensive DFT calculations.

15.
Chemistry ; 28(14): e202104157, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35147254

RESUMO

Perovskite is a promising non-noble catalyst and has been widely investigated for the electrochemical oxygen evolution reaction (OER). However, there is still serious lack of valid approaches to further enhance their catalytic performance. Herein, we propose a spin state modulation strategy to improve the OER electrocatalytic activity of typical perovskite material of LaCoO3 . Specifically, the electronic configuration transition was realized by a simple high temperature thermal reduction process. M-H hysteresis loop results reveal that the reduction treatment can produce more unpaired electrons in 3d orbit by promoting the electron transitions of Co from low spin state to high spin state, and thus lead to the increase of the spin polarization. Electrochemical measurements show that the catalytic performance of LaCoO3 is strongly dependent on its electronic configuration. With the optimized reduction treatment, the overpotential for the OER process in 0.5 M KOH electrolyte solution at 10 mA cm-2 current density was 396 mV, significantly lower than that of the original state. Furthermore, it can mediate efficient OER with an overpotential of 383 mV under an external magnetic field, which is attributed to the appropriate electron filling. Our results show that electron spin state regulation is a new way to boost the OER electrocatalytic activity.

16.
Inorg Chem ; 61(46): 18670-18677, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36346947

RESUMO

The reaction of the germylene chloride (NacNac)GeCl (1, NacNac = CH{(CMe)(2,6-iPr2C6H3N)}2), phenylacetylene, and B(C6F5)3 gives the intermolecular frustrated Lewis pair (FLP) addition product 2. In this case, the Ge(II) center acts as a base. In contrast, the analogous reaction of germylene thiocyanate 3 reacts independently with B(C6F5)3 to give the germylene cation salt [(NacNac)Ge][SCNB(C6F5)3] 4. Subsequent in the presence of alkynes, the Ge(II) cation and γ-C of 4 act as a Lewis acidic and basic center, respectively, to affect the addition of alkynes, affording products [(NacNac)Ge(RCCR')][SCNB(C6F5)3] 5 and 6. Compound 4 also reacts with Me3SiCN to give the cyanide-bridged Ge/B species 7, which also reacts with phenylacetylene to give CN abstraction and intramolecular addition yielding the salt [(NacNac)Ge(PhCCH)][NCB(C6F5)3] 8. Despite the similarity of 1 and 3, DFT calculations show that the highest occupied molecular orbital (HOMO) of 1 is mainly located at the more sterically hindered germylene center, while the HOMO of 3 is located on the less sterically hindered NCS group, prompting markedly different FLP addition products.

17.
Bioorg Chem ; 124: 105818, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35489271

RESUMO

The simultaneous analysis of amino acids (AAs) is crucial for human health, diagnosis and treatment of disease, and nutritional quality evaluation in foodstuffs. Here, we establish an easy and rapid method for the simultaneous analysis of AAs using a single reagent 2-(trifluoromethyl)benzaldehyde (oTFMBA) based on spectral-separation-enabled 19F NMR spectroscopy. oTFMBA, a highly sensitive chemosensor, is capable of analyzing 19 proteinogenic AAs or non-amino acid amines (non-AAs) in a complex mixture by adjusting the pH in a toilless way. The 19F signals of oTFMBA-labeled AAs are distributed over a wide range of ∼ 0.7 ppm, demonstrating oTFMBA with higher resolution for simultaneous analysis of AAs compared to the o-phthaldialdehyde (OPA) method (<0.6 ppm). Additionally, 12 AAs were unambiguously identified in human urine, including Asp, Ser, Gly, Thr, Glu, Arg, Ala, Val, Ile, Tyr, His, and Phe. Furthermore, our method's detection limit for AAs is 5.83 µM, illustrating sensitivity with an ∼100-fold improvement over the OPA method. This work represents an approach to the analysis of AAs or non-AAs in a complicated mixture (even biofluid) using a 19F NMR probe with high sensitivity, which is of great significance for the simultaneous analysis of multiple analytes.


Assuntos
Aminoácidos , Fragmentos de Peptídeos , Aminas , Sequência de Aminoácidos , Humanos , Espectroscopia de Ressonância Magnética , Tripsina
18.
BMC Pregnancy Childbirth ; 22(1): 297, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35392848

RESUMO

BACKGROUND: Fetal growth restriction (FGR) in utero leads to failure of fetus to reach the genetically normal growth potential. Currently available means of treating FGR are limited. And it remains unknown how pregnant women who give birth to FGR fetus differ in gut microbiota composition from normal pregnant women. METHODS: In this case-control study, fecal samples were obtained from maternal rectum in the operation room by an obstetrician under strict aseptic conditions. We compared gut microbiota of 14 pregnant women with FGR and 18 normal controls by performing 16S rDNA amplicon sequencing. RESULTS: We identified significant differences in ß-diversity between the FGR and control groups (P < 0.05). At genus level, Bacteroides, Faecalibacterium and Lachnospira were highly abundant in the FGR subjects, which are significantly enriched in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways related to glycometabolism. CONCLUSION: These findings demonstrated that the distinct composition of the gut microbiota between FGR and normal pregnant women could contribute to an improved understanding of the prevention and treatment of FGR.


Assuntos
Microbioma Gastrointestinal , Estudos de Casos e Controles , Feminino , Retardo do Crescimento Fetal , Feto , Humanos , Gravidez , Gestantes
19.
BMC Public Health ; 22(1): 336, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-35177008

RESUMO

BACKGROUND: Metabolic syndrome has become a major health threat throughout the world, but there are few studies that focus on the effects of housework on human metabolism. This study explores the association between housework and metabolic markers and examines whether there are gender differences in the relationship of housework intensity on these markers. METHODS: We obtained data for 2,624 participants from the China Health and Nutrition Survey and used binary logistic regression to analyze the association between housework and metabolic markers (triglycerides, high- and low-density lipoprotein cholesterol, hemoglobin, blood glucose, cholesterol, and blood pressure). RESULTS: We observed no association between housework and metabolic markers for men. However, we find that women who engaged in housework had a higher risk of triglycerides than those who did not (OR=1.16, 95% CI: 1.16, 4.25). Compared with low-intensity, we also find that women who performed moderate- and high-housework intensity had a higher risk of triglycerides (moderate-intensity: OR=1.78, 95% CI: 1.14, 2.78; high-intensity: OR=1.91, 95% CI: 1.22, 2.98), MetS (OR=1.54, 95% CI: 0.98, 2.43; OR=1.68, 95% CI: 1.07, 2.66), pre-hypertension (OR=1.68, 95% CI: 1.08, 2.62; OR=1.63, 95% CI: 1.04, 2.55), and obesity (OR=1.65, 95% CI: 1.01, 2.70; OR=1.66, 95% CI: 1.01, 2.72). CONCLUSION: In women, we find that housework is positively associated with the metabolic markers, triglycerides, MetS, and pre-hypertension. However, we did not find evidence that this relationship exists in men, f or any biomarkers we considered. One possible explanation is that people who engage in high-intensity housework are more stressed and sleep less, which could be a mechanism by which housework becomes associated with metabolic disease.


Assuntos
Síndrome Metabólica , Pré-Hipertensão , Biomarcadores , Glicemia/metabolismo , China/epidemiologia , Colesterol , HDL-Colesterol , Feminino , Zeladoria , Humanos , Estudos Longitudinais , Masculino , Fatores de Risco , Fatores Sexuais , Triglicerídeos
20.
Mediators Inflamm ; 2022: 2782080, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35125963

RESUMO

METHODS: A rat hyperalgesia model was induced using an intraplantar injection of Freund's complete adjuvant (FCA) or an intrathecal injection of IL-6. Mechanical allodynia was evaluated using von Frey filament tests after intrathecal injections of T-5224 (c-Fos/AP-1 inhibitor), minocycline (Mino, a specific microglia inhibitor), L-2-aminoadipic acid (LAA, an astroglial toxin), PKCε inhibitor peptide, APTSTAT3-9R (STAT3 inhibitor), or anti-IL-6 antibody. The c-Fos, GFAP, Iba-1, PKCε, STAT3, pSTAT3Tyr705 and pSTAT3Ser727, and IL-6 expression at the spinal cord level was assessed by Western blot analysis. The interactive effects of PKCε and STAT3 were determined using immunofluorescence staining and immunoprecipitation in vivo and in vitro. Interleukin-6 promoter activity was examined using luciferase assays. RESULTS: T-5224, Mino, and LAA attenuated FCA- or IL-6-mediated inflammatory pain, with a decrease in c-Fos, GFAP, Iba-1, PKCε, and IL-6 expression. PKCε inhibitor peptide and APTSTAT3-9R reversed FCA-induced nociceptive behavior, while decreasing pSTAT3Ser727, IL-6, c-Fos, GFAP, and Iba-1 expression and PKCε and STAT3 coexpression. Interleukin-6 promoter activity increased in the presence of PKCε and STAT3. The interaction with PKCε increased on phosphorylating STAT3 at Ser727 but not at Tyr705. CONCLUSION: STAT3 phosphorylation at Ser 727 and the interaction with PKCε contribute to hyperalgesia via the IL-6-mediated signaling pathway, thus regulating neuron-glia crosstalk during inflammatory pain.


Assuntos
Hiperalgesia , Interleucina-6 , Animais , Hiperalgesia/metabolismo , Interleucina-6/metabolismo , Neuroglia/metabolismo , Neurônios/metabolismo , Fosforilação , Proteína Quinase C-épsilon/metabolismo , Proteína Quinase C-épsilon/farmacologia , Ratos , Medula Espinal/metabolismo
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