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1.
Mol Psychiatry ; 29(5): 1253-1264, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38228891

RESUMO

The pathophysiology of autism spectrum disorders (ASDs) is causally linked to postsynaptic scaffolding proteins, as evidenced by numerous large-scale genomic studies [1, 2] and in vitro and in vivo neurobiological studies of mutations in animal models [3, 4]. However, due to the distinct phenotypic and genetic heterogeneity observed in ASD patients, individual mutation genes account for only a small proportion (<2%) of cases [1, 5]. Recently, a human genetic study revealed a correlation between de novo variants in FERM domain-containing-5 (FRMD5) and neurodevelopmental abnormalities [6]. In this study, we demonstrate that deficiency of the scaffolding protein FRMD5 leads to neurodevelopmental dysfunction and ASD-like behavior in mice. FRMD5 deficiency results in morphological abnormalities in neurons and synaptic dysfunction in mice. Frmd5-deficient mice display learning and memory dysfunction, impaired social function, and increased repetitive stereotyped behavior. Mechanistically, tandem mass tag (TMT)-labeled quantitative proteomics revealed that FRMD5 deletion affects the distribution of synaptic proteins involved in the pathological process of ASD. Collectively, our findings delineate the critical role of FRMD5 in neurodevelopment and ASD pathophysiology, suggesting potential therapeutic implications for the treatment of ASD.


Assuntos
Transtorno do Espectro Autista , Modelos Animais de Doenças , Proteínas de Membrana , Transtornos do Neurodesenvolvimento , Animais , Camundongos , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/metabolismo , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Masculino , Neurônios/metabolismo , Comportamento Animal/fisiologia , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Camundongos Knockout , Transtorno Autístico/genética , Transtorno Autístico/metabolismo , Camundongos Endogâmicos C57BL , Comportamento Social , Comportamento Estereotipado , Sinapses/metabolismo , Feminino
2.
Plant Physiol ; 191(4): 2427-2446, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36508351

RESUMO

Salt and drought stresses are major factors limiting soybean (Glycine max [L.] Merr.) growth and development; thus, improving soybean stress tolerance is critical. In this study, both salt stress and drought stress induced mRNA levels of CONSTANS-like 1a (GmCOL1a) and stabilized the GmCOL1a protein. Transgenic 35S:GmCOL1a soybean plants exhibited enhanced salt and drought tolerance, with higher relative water content in leaves, greater proline content, lower malondialdehyde (MDA) content, and less reactive oxygen species (ROS) production compared with wild-type plants; the GmCOL1a knockout co-9 mutant showed opposite phenotypes. In addition, GmCOL1a promoted the expression of genes related to salt tolerance, effectively reducing the Na+/K+ ratio in soybean plants, especially in stems and leaves of 35S:GmCOL1a soybean. Chromatin immunoprecipitation sequencing (ChIP-seq) analysis identified two potential direct targets of GmCOL1a, late embryogenesis abundant (GmLEA) and Δ1-pyrroline-5-carboxylate synthetase (GmP5CS) genes, which were verified by chromatin immunoprecipitation quantitative polymerase chain reaction (ChIP-qPCR), electrophoretic mobility shift assay (EMSA), and transient transcriptional activation assays. GmCOL1a bound directly to the Myc(bHLH)-binding and Che-binding motifs of GmLEA and GmP5CS promoters to stimulate mRNA expression. Analysis of transgenic hairy-root GmP5CS:GmP5CS soybean plants in wild type, co-9, and 35S:GmCOL1a backgrounds further revealed that GmCOL1a enhances salt and drought tolerance by promoting GmP5CS protein accumulation in transgenic soybean hairy roots. Therefore, we demonstrate that GmCOL1a plays an important role in tolerance to abiotic stress in soybean.


Assuntos
Resistência à Seca , Glycine max , Glycine max/metabolismo , Proteínas de Plantas/metabolismo , Estresse Salino , Tolerância ao Sal/genética , Estresse Fisiológico/genética , Secas , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de Plantas
3.
Plant Physiol ; 193(1): 775-791, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37204820

RESUMO

Flowering time, maturity, and plant height are crucial agronomic traits controlled by photoperiod that affect soybean (Glycine max [L.] Merr.) yield and regional adaptability. It is important to cultivate soybean cultivars of earlier maturity that adapt to high latitudes. GAMYB-binding protein 1 (GmGBP1), a member of the SNW/SKIP family of transcriptional coregulators in soybean, is induced by short days and interacts with transcription factor GAMYB (GmGAMYB) during photoperiod control of flowering time and maturity. In the present study, GmGBP1:GmGBP1 soybean showed the phenotypes of earlier maturity and higher plant height. Chromatin immunoprecipitation sequencing (ChIP-seq) assays of GmGBP1-binding sites and RNA sequencing (RNA-seq) of differentially expressed transcripts in GmGBP1:GmGBP1 further identified potential targets of GmGBP1, including small auxin-up RNA (GmSAUR). GmSAUR:GmSAUR soybean also showed earlier maturity and higher plant height. GmGBP1 interacted with GmGAMYB, bound to the promoter of GmSAUR and promoted the expression of FLOWER LOCUS T homologs 2a (GmFT2a) and FLOWERING LOCUS D LIKE 19 (GmFDL19). Flowering repressors such as GmFT4 were negatively regulated, resulting in earlier flowering and maturity. Furthermore, the interaction of GmGBP1 with GmGAMYB increased the gibberellin (GA) signal to promote height and hypocotyl elongation by activating GmSAUR and GmSAUR bound to the promoter of the GA-positive activating regulator gibberellic acid-stimulated Arabidopsis 32 (GmGASA32). These results suggested a photoperiod regulatory pathway in which the interaction of GmGBP1 with GmGAMYB directly activated GmSAUR to promote earlier maturity and plant height in soybean.


Assuntos
Glycine max , Proteínas de Plantas , Fatores de Transcrição , Hipocótilo/metabolismo , Fotoperíodo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , RNA de Plantas/genética , Transdução de Sinais , Glycine max/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica
4.
Nanotechnology ; 35(15)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38211323

RESUMO

MXene two-dimensional materials have been widely used in energy storage, catalysis, sensing and other fields, Nb2C as a typical two-dimensional MXene material, its exploration in the field of optoelectronics is still in its infancy, especially Nb2C-based photodetectors are still to be developed. This paper demonstrates that two-dimensional films based on few-layer Nb2C have a photoelectric response in the wavelength range from visible to near-infrared. We have found that the light response performance can be easily adjusted by controlling the thickness of the spin-coated film, and that Nb2C photodetectors show great advantages in terms of wide bandwidth, polarization response, high switching ratio, etc. By adjusting the material concentration and sample thickness, the photocurrent can reach up to 330 nA, the switching ratio can reach 410, and the responsivity can reach 8.3 × 10-4A W-1. In the polarization characteristic test, an extinction ratio of 7.6 can be obtained. By adjusting the content of that doped MoS2quantum dot, the dark current can reach 7.6 × 10-13A, and the switching ratio can reach 3 × 105, which can be increased by 700 times. The above results show that the few-layer Nb2C nanosheets can be used as optoelectronic detectors in the visible to near-infrared bands, which further broadens the application prospects of two-dimensional MXene.

5.
J Nat Prod ; 87(6): 1582-1590, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38785214

RESUMO

Bioactivity-based molecular networking-guided fractionation enabled the isolation of three new polycyclic tetramic acids bearing cis-decalin, epicolidines A-C (1-3), along with one known compound, PF 1052 (4), from the endophytic fungus Epicoccum sp. 1-042 collected in Tibet, China. Their structures were assigned on the basis of extensive spectroscopic data, partial hydrolysis, advanced Marfey's method, quantum chemistry calculations, and X-ray diffraction analysis. Compounds 2-4 displayed promising activities against Gram-positive bacteria in vitro. Particularly, compound 4 displayed remarkable potential against vancomycin-resistant Enterococcus faecium (VRE) with an MIC value of 0.25 µg/mL, lower than the MIC (0.5 µg/mL) of the antibiotic combination quinupristin/dalfopristin (Q/D). In a further in vivo study, compound 4 increased the survival rate to 100% in the VRE-G. mellonella infection model at a concentration of 10 mg/kg.


Assuntos
Antibacterianos , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química , Estrutura Molecular , Ascomicetos/química , Tibet , Animais , Enterococcus faecium/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Pirrolidinonas/farmacologia , Pirrolidinonas/química , Pirrolidinonas/isolamento & purificação
6.
Bioorg Chem ; 147: 107396, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705108

RESUMO

RN-9893, a TRPV4 antagonist identified by Renovis Inc., showcased notable inhibition of TRPV4 channels. This research involved synthesizing and evaluating three series of RN-9893 analogues for their TRPV4 inhibitory efficacy. Notably, compounds 1b and 1f displayed a 2.9 to 4.5-fold increase in inhibitory potency against TRPV4 (IC50 = 0.71 ± 0.21 µM and 0.46 ± 0.08 µM, respectively) in vitro, in comparison to RN-9893 (IC50 = 2.07 ± 0.90 µM). Both compounds also significantly outperformed RN-9893 in TRPV4 current inhibition rates (87.6 % and 83.2 % at 10 µM, against RN-9893's 49.4 %). For the first time, these RN-9893 analogues were profiled in an in vivo mouse model, where intraperitoneal injections of 1b or 1f at 10 mg/kg notably mitigated symptoms of acute lung injury induced by lipopolysaccharide (LPS). These outcomes indicate that compounds 1b and 1f are promising candidates for acute lung injury treatment.


Assuntos
Lesão Pulmonar Aguda , Benzenossulfonamidas , Sulfonamidas , Canais de Cátion TRPV , Relação Estrutura-Atividade , Canais de Cátion TRPV/antagonistas & inibidores , Canais de Cátion TRPV/metabolismo , Lesão Pulmonar Aguda/tratamento farmacológico , Sulfonamidas/química , Sulfonamidas/farmacologia , Sulfonamidas/síntese química , Animais , Camundongos , Humanos , Estrutura Molecular , Relação Dose-Resposta a Droga , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Masculino , Camundongos Endogâmicos C57BL
7.
Environ Res ; 246: 118126, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38199463

RESUMO

Livestock grazing is an influencing factor playing a key role in shaping the plant community, microbial community, and soil properties in grassland ecosystems. Northern China's Loess Plateau has been used for livestock grazing for centuries and is a vulnerable ecosystem. In this study, the fates of bacterial and fungal communities of the typical steppe of the Loess Plateau were investigated under increasing grazing intensities practiced in summer and winter seasons. The results revealed changes in soil physiochemical properties, plant community properties, and microbial diversity in response to alterations in the grazing intensity. The alpha diversity of microbial communities (including bacteria and fungi) exhibited an uneven trend during summer grazing due to an increase in grazing intensity, but it decreased during winter grazing; however, the observed changes were not significant. The beta diversity of the bacterial community was highly influenced by grazing intensity, the summer community clustered near nongrazing, and the winter community presented significantly different results. The beta diversity of the fungal community was not influenced by grazing intensity or season. Grazing induced the growth of fast-growing bacteria (such as Actinobacteria and Firmicutes) and saprophytic fungi and a reduction in overall pathogenic traits. Co-occurrence network analysis and a structural equation model revealed changes in soil and plant properties (such as soil nitrogen level, soil organic carbon level, aboveground biomass, and litter biomass), with an increase in grazing intensity contributing to alterations in bacterial and fungal diversities. This finding demonstrates that grazing intensity can directly affect soil microbes and play an indirect role by modifying soil nutrients and reducing plant biomass, which eventually contributes to changes in microbial communities. Overall, implementing low grazing intensity is suggested for maintaining the microbial community structure the same as that of the native microbiome (ungrazed) in the steppe ecosystems.


Assuntos
Ecossistema , Microbiota , Estações do Ano , Carbono/análise , Solo/química , Biomassa , Microbiologia do Solo , Plantas , Bactérias
8.
Immun Ageing ; 21(1): 15, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378602

RESUMO

BACKGROUND: With the development of Hematopoietic Stem Cell Transplantation (HSCT) technology, increasing numbers of elderly patients were undergoing allogeneic HSCT and elderly patients with hematologic malignancies could benefit most from it. Preformed donor-specific human leukocyte antigen (HLA) antibodies (DSA) were associated with graft failure in HLA-mismatched allogeneic HSCT and the absence of DSA was the main criterion of selecting the donor. Except for sensitization events such as transfusion, pregnancy or previous transplantation, ageing affects the humoral immune response both quantitatively and qualitatively. To evaluate the prevalence and distribution of anti-HLA and antibodies of MHC class I chain related antigens A (MICA) specificities in different age groups before initial HSCT would provide HLA and MICA specific antibody profiles under the impact of ageing, which could provide meaningful information in the process of selecting suitable HLA-mismatched donors by avoiding preformed DSA. RESULTS: There were no significant differences in the distribution of anti-HLA class I, class II and anti-MICA antibodies among the three age groups in this study except that a significant lower negative ratio of anti-HLA class I, class II antibodies and higher positive rate of MICA antibodies with maximum mean fluorescent intensity (MFI) > 5000 in the elderly than in young age group. The distribution of antibody specificities against HLA -A, -B, -C, -DR, -DQ, -DP and MICA antigens in the three age groups were generally consistent. The anti-HLA class I antibody specificities with higher frequencies were A80,A68;B76,B45;Cw17, which were unlikely to become DSA in Chinese. Anti-HLA class II antibody specificities were more likely to become potential DSA than class I.DR7, DR9, DQ7, DQ8 and DQ9 were most likely to become potential DSA. CONCLUSIONS: The prevalence of anti-HLA and anti-MICA antibodies increased slightly as age increased. While ageing had a small impact on the distribution of antibody specificity frequencies against HLA-A, -B, -C, -DR,-DQ, -DP and MICA antigens in recipients awaiting initial HSCT from East China. The risk of developing preformed DSA was basically consistent in the three age groups and the elderly group might be more favorable in HLA-mismatched HSCT due to higher positive rate of anti-MICA antibody.

9.
BMC Geriatr ; 24(1): 208, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424506

RESUMO

OBJECTIVE: To evaluate the dynamics of basic activity of daily living (BADL) in older patients with acute lower respiratory tract infections (LRTIs) during acute phase and to investigate risk factors associated with decreased physical function at discharge. METHODS: We conducted a prospective cohort study of patients aged 65 years and older who were hospitalized for acute LRTIs between April 15, 2020 and January 15, 2023. All patients received geriatric assessment at admission, including emotion, cognition, frailty, physical function status and so on. The BADL was also evaluated by the Barthel Index (BI) at two weeks before admission by recall (baseline status), at admission and at discharge. Based on the BI grades at baseline and at discharge, patients were classified into two groups: ADL decline and no ADL decline. Multivariable adjusted logistic regression models were used to evaluate the risk factors of decreased physical function. RESULTS: A total of 364 older survivors with LRTIs were included in the analysis. The median age was 74 years (IQR 61.0-82.0), 231 (62.6%) were male, the median length of stay was 10 days. In the geriatric assessment, 139 patients (38.2%) were classified as frailty, 137 patients (37.6%) experienced insomnia, 60 patients (16.5%) exhibited cognitive impairments, and 37 patients (10.2%) were defined as malnutrition. Additionally, 30 patients (8.2%) dealt with emotional disorders. On average, patients were taking 3 medications, and Charlson Comorbidity Index score was 4. 72 patients (19.8%) had function decline at discharge. In the multivariable analysis, frailty status had an odds ratio of 4.25 (95% CI 1.31-19.26) for decreased physical function and cognitive impairment had an odds ratio of 2.58 (95% CI 1.27-5.19). CONCLUSIONS: About 20% older patients with LRTIs experienced functional decline at discharge. Compared to age, severity of diseases and length of stay, frailty and cognitive impairment performed better at predicting the function decline. The apply of geriatric assessment may contribute to enhance the quality of management and treatment for patients with the older with LRTIs.


Assuntos
Fragilidade , Idoso , Humanos , Masculino , Feminino , Estudos Prospectivos , Hospitalização , Fatores de Risco , Avaliação Geriátrica , Hospitais , Atividades Cotidianas
10.
Ecotoxicol Environ Saf ; 281: 116600, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38896901

RESUMO

Arsenic pollution control technology in water was important to ensure environmental health and quality safety of agricultural products. Therefore, the adsorption performance of three adsorbents for chitosan, sepiolite, and Zeolitic Imidazolate Framework-8 (ZIF-8) were investigated in arsenate contaminated water. The results revealed that the adsorption capacity of ZIF-8 was higher than that of chitosan and sepiolite. The analysis of adsorption isotherm models showed that the behavior of ZIF-8 was more consistent with the Langmuir model. Furthermore, the adsorption mechanisms of three adsorbents for arsenate were investigated by Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The analysis of FTIR showed that ZIF-8 maintained the stability of the interaction with arsenate by forming As-O chemical bonds. However, the effect of chitosan and sepiolite with arsenate was mainly physical adsorption. The analysis of XPS showed that the absorption of ZIF-8 with arsenate involved metal sites and nitrogen through the characteristic peak and the change of the binding energy. Furthermore, the impact of microplastics as a widespread coexistence pollutant in the water on adsorbent performance was investigated. The results indicated that the adsorption capacity of ZIF-8 was almost not affected by microplastics. The maximum adsorption amount of arsenate was changed from 73.45 mg/g to 81.89 mg/g. However, the maximum adsorption amount of chitosan and sepiolite decreased by 31.4 % and 11.6 %, respectively. The analysis of FTIR and XPS revealed that ZIF-8 enhances arsenate adsorption by forming N-O-As bonds in the presence of microplastics. This study provides scientific evidence for the management of arsenate pollution in water bodies, especially in complex water bodies containing microplastics.

11.
Chem Biodivers ; 21(5): e202400300, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38430215

RESUMO

Sea buckthorn, a traditional medicinal plant, has been used for several years in China for the prevention and treatment of various diseases, a practice closely associated with its significant antioxidant activity. The aim of this study was to investigate the protective effects of sea buckthorn flavonoids on vascular endothelial cells in an oxidative stress environment. We isolated and extracted active compounds from sea buckthorn and investigated their impact on endothelial nitric oxide synthase (eNOS) activity through the PI3K/AKT-eNOS signaling pathway through a combination of network pharmacology and cellular experiments, elucidating the regulatory effects of these compounds on endothelial cell functions. Three flavonoids, named Fr.4-2-1, Fr.4-2-2 and Fr.4-2-3, were obtained from sea buckthorn. The results of network pharmacology indicated that they might exert their effects by regulating the PI3K-AKT signaling pathway. In vitro results showed that all three flavonoids were effective in alleviating the degree of oxidative stress in cells, among which Fr.4-2-1 exerted its antioxidant effects by modulating the PI3K/AKT-eNOS pathway. Flavonoids in sea buckthorn can effectively inhibit oxidative stress-induced cellular damage, preserving the integrity and functionality of endothelial cells, which is crucial for maintaining vascular health and function.


Assuntos
Flavonoides , Hippophae , Óxido Nítrico Sintase Tipo III , Estresse Oxidativo , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Hippophae/química , Óxido Nítrico Sintase Tipo III/metabolismo , Flavonoides/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Humanos , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Substâncias Protetoras/química , Substâncias Protetoras/isolamento & purificação
12.
Molecules ; 29(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38731458

RESUMO

Utilizing hydrogen as a viable substitute for fossil fuels requires the exploration of hydrogen storage materials with high capacity, high quality, and effective reversibility at room temperature. In this study, the stability and capacity for hydrogen storage in the Sc-modified C3N4 nanotube are thoroughly examined through the application of density functional theory (DFT). Our finding indicates that a strong coupling between the Sc-3d orbitals and N-2p orbitals stabilizes the Sc-modified C3N4 nanotube at a high temperature (500 K), and the high migration barrier (5.10 eV) between adjacent Sc atoms prevents the creation of metal clusters. Particularly, it has been found that each Sc-modified C3N4 nanotube is capable of adsorbing up to nine H2 molecules, and the gravimetric hydrogen storage density is calculated to be 7.29 wt%. It reveals an average adsorption energy of -0.20 eV, with an estimated average desorption temperature of 258 K. This shows that a Sc-modified C3N4 nanotube can store hydrogen at low temperatures and harness it at room temperature, which will reduce energy consumption and protect the system from high desorption temperatures. Moreover, charge donation and reverse transfer from the Sc-3d orbital to the H-1s orbital suggest the presence of the Kubas effect between the Sc-modified C3N4 nanotube and H2 molecules. We draw the conclusion that a Sc-modified C3N4 nanotube exhibits exceptional potential as a stable and efficient hydrogen storage substrate.

13.
Angew Chem Int Ed Engl ; 63(29): e202405382, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38682252

RESUMO

Isotactic polythioesters (PTEs) that are thioester analogs to natural polyhydroxyalkanoates (PHAs) have attracted growing attention due to their distinct properties. However, the development of chemically synthetic methods for preparing isotactic PTEs has long been an intricate endeavour. Herein, we report the successful synthesis of perfectly isotactic PTEs via stereocontrolled ring-opening polymerization. This binaphthalene-salen aluminium (SalBinam-Al) catalyst promoted a robust polymerization of rac-α-substituted-ß-propiothiolactones (rac-BTL and rac-PTL) with highly kinetic resolution, affording perfectly isotactic P(BTL) and P(PTL) with Mn up to 276 kDa. Impressively, the isotactic P(BTL) formed a supramolecular stereocomplex with improved thermal property (Tm=204 °C). Ultimately, this kinetic resolution polymerization enabled the facile isolation of enantiopure (S)-BTL, which could efficiently convert to an important pharmaceutical building block (S)-2-benzyl-3-mercapto-propanoic acid. Isotactic P(PTL) served as a tough and ductile material comparable to the commercialized polyolefins. This synthetic system allowed to access of isotactic PTEs, establishing a powerful platform for the discovery of sustainable plastics.

14.
Anal Chem ; 95(2): 1385-1394, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36577018

RESUMO

To fully understand the function of the phytohormone indole-3-acetic acid (IAA) in regulating plant growth and development, we need to monitor their levels and distribution with high spatial and temporal resolution. In this work, an anthracene-based fluorescent biosensor for IAA was prepared using bovine serum albumin (BSA) as a bio-template. The single linear oxygen (1O2) specifically produced by IAA catalyzed with horseradish peroxidase (HRP) turns on the fluorescence of the probe, enabling specific trace sensing of IAA in the presence of multiple structural analogues. The presence of the bio-template BSA extends the biocompatibility of the probe, enabling visual monitoring of the level and distribution signal of endogenous IAA of plants in the field of bioimaging. In addition, the strategy has shown potential for application in portable paper-based sensors and in vivo fluorescent flower culture. This work provides a technical and theoretical basis for exploring the growth regulatory mechanisms of IAA in plants at the molecular level.


Assuntos
Ácidos Indolacéticos , Plantas , Ácidos Indolacéticos/química , Peroxidase do Rábano Silvestre/química , Reguladores de Crescimento de Plantas , Corantes , Oxigênio
15.
Opt Express ; 31(19): 31221-31230, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37710646

RESUMO

A complex phase space and ray method is proposed to present intuitive interpretation of unique intensity profiles, parabolic accelerating trajectories, and distinctive phase shifts of Airy beam and its exponentially decaying version (i.e., finite-energy Airy beam). In the complex phase space, finite-energy Airy beam manifests itself as a complex parabolic phase space curve (PSC) which represents a cluster of light rays with complex wave vectors. The complex ray cluster converges to a complex parabolic caustic curve in complex coordinate space. For infinite-energy Airy beam, phase space, PSC, light ray and caustic curve change to real values. In the paraxial condition, Airy beams can maintain parabolic form of PSC and keep constant ray density, which guarantees the non-diffraction property of Airy beam and approximate non-diffraction property of finite-energy Airy beam. From the evolution of vertexes of parabolic PSC along a parabolic trajectory in phase space, one can also give the parabolic caustic curve for Airy beam and the complex parabolic caustic curve for exponentially decaying Airy beam. Further, the special phase and decay factors in the propagating solution of complex amplitude of Airy beams can be directly derived from the phase shifts of light ray cluster along transverse and longitudinal directions. The proposed phase space and ray method can present intuitive comprehension to distinctive propagating characteristics of Airy beams including intensity and phase, without resort to solving wave equation or diffracting integral formula.

16.
Opt Express ; 31(2): 1813-1831, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785208

RESUMO

The image reconstruction for Fourier-domain optical coherence tomography (FD-OCT) could be achieved by iterative methods, which offer a more accurate estimation than the traditional inverse discrete Fourier transform (IDFT) reconstruction. However, the existing iterative methods are mostly A-line-based and are developed on CPU, which causes slow reconstruction. Besides, A-line-based reconstruction makes the iterative methods incompatible with most existing image-level image processing techniques. In this paper, we proposed an iterative method that enables B-scan-based OCT image reconstruction, which has three major advantages: (1) Large-scale parallelism of the OCT dataset is achieved by using GPU acceleration. (2) A novel image-level cross-domain regularizer was developed, such that the image processing could be performed simultaneously during the image reconstruction; an enhanced image could be directly generated from the OCT interferogram. (3) The scalability of the proposed method was demonstrated for 3D OCT image reconstruction. Compared with the state-of-the-art (SOTA) iterative approaches, the proposed method achieves higher image quality with reduced computational time by orders of magnitude. To further show the image enhancement ability, a comparison was conducted between the proposed method and the conventional workflow, in which an IDFT reconstructed OCT image is later processed by a total variation-regularized denoising algorithm. The proposed method can achieve a better performance evaluated by metrics such as signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), while the speed is improved by more than 30 times. Real-time image reconstruction at more than 20 B-scans per second was realized with a frame size of 4096 (axial) × 1000 (lateral), which showcases the great potential of the proposed method in real-world applications.

17.
Environ Sci Technol ; 57(39): 14602-14610, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37713478

RESUMO

Deep-sea sediments (>1000 m) are often considered to be the ultimate sink for black carbon (BC), and the long-term buried BC in these sediments is believed to potentially provide a negative feedback effect on climate warming. The burial flux of BC in marine sediments is predominantly estimated based on soot BC (SBC) in most studies, frequently ignoring the contribution of char BC (CBC). While this methodology may result in an underestimation of the BC burial flux, the precise extent of this underestimation is yet to be determined. This study used the benzene poly(carboxylic acid) (BPCA) method and chemothermal oxidation (CTO) method to analyze CBC and SBC in four deep-sea sediment cores from the Zhongnan seamount in the South China Sea, respectively. The CBC content increased from 0.026 ± 0.010% at the seamount upper part (1432 m) to 0.039 ± 0.012% at the seamount foot (4278 m), constituting approximately 25 to 42% of the SBC content. The content disparity between CBC and SBC diminishes as depth increases. In deep-sea sediments, biogeochemical factors influence the variation of CBC molecules with depth. In the seamount middle-upper part (1432 and 2465 m), highly condensed CBC gradually accumulated along the core downward profile. In the sediment core profile of the seamount middle-lower part (3497 m), benzenetricarboxylic acid and benzenetetracarboxylic acid content decreased while the BC condensation degree rose, i.e., less condensed CBC was preferentially consumed. Afterward, CBC molecules reached a relatively stable state at the seamount foot. This study reveals that CBC possesses the capacity for long-term carbon sequestration in deep-sea sediments, and its content is not negligible.


Assuntos
Sedimentos Geológicos , Fuligem , Sedimentos Geológicos/química , Fuligem/análise , Ácidos Carboxílicos , Carbono , China , Monitoramento Ambiental/métodos
18.
J Clin Periodontol ; 50(11): 1476-1486, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37596796

RESUMO

AIM: The study aimed to provide evidence of the relationship between probiotics consumption and periodontitis. MATERIALS AND METHODS: A total of 4577 adults who participated in the National Health and Nutrition Examination Survey (NHANES) during 2009-2014 were included in the study. The weighted prevalence of periodontitis was compared among different groups, and a weighted binary logistic regression analysis was conducted to explore the relationship between probiotic consumption and periodontitis. Receiver operating characteristic (ROC) curves were used to assess the role of probiotic consumption in the periodontitis prediction model. RESULTS: Participants who consumed probiotics had a significantly lower prevalence of periodontitis than those who did not (41.08% vs. 27.83%, p < .001). After fully adjusting for all factors, the odds ratio associated with periodontitis for consuming probiotics was 0.70 (95% confidence interval 0.54-0.92, p = .01) when compared with those who did not consume probiotics. A predictive model including age, sex, ethnicity, poverty income ratio, smoking status and probiotics had 77.0% sensitivity and 60.3% specificity in detecting periodontitis in US adults and achieved an area under the ROC curve of 0.749. CONCLUSIONS: These results indicate that consuming probiotics is associated with a reduced risk of periodontitis.


Assuntos
Periodontite , Probióticos , Adulto , Humanos , Inquéritos Nutricionais , Periodontite/epidemiologia , Periodontite/prevenção & controle , Fumar/epidemiologia , Renda , Probióticos/uso terapêutico , Prevalência
19.
Lipids Health Dis ; 22(1): 186, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37924128

RESUMO

BACKGROUND: The elevation of TyG is considered an important factor in promoting the progression of non-alcoholic fatty liver disease (NAFLD), but its impact on the degree of liver steatosis remains unclear. This study aims to explore the relationship between TyG and TyG-related indices, such as triglyceride glucose-body mass index (TyG-BMI), with the degree of liver fat accumulation. METHODS: From January 2021 to March 2022, 1171 participants underwent health check-ups, and all underwent FibroScan transient elastography. The analysis focused on identifying the factors that contribute to the onset of NAFLD and the degree of hepatic steatosis. RESULTS: The predictive value of TyG-BMI (OR = 1.039, 95% CI 1.031-1.046) in triggering NAFLD development was greater than that of TyG alone. The areas under the curve for TyG-BMI and TyG were calculated at 0.808 and 0.720, respectively. TyG-BMI (OR = 1.034, P < 0.001) was identified as a main independent factor affecting hepatic steatosis severity. With each incremental increase in TyG-BMI, the likelihood of experiencing an increase in the extent of hepatic steatosis was 1.034 times higher than that of the preceding unit. CONCLUSIONS: The TyG-BMI showed higher accuracy in predicting NAFLD than did the TyG, and was more closely linked to the severity of hepatic steatosis. Therefore, it can be included as a parameter in health management centers and should be widely used to screen and evaluate patients with NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Glucose , Índice de Massa Corporal , Triglicerídeos
20.
J Ind Microbiol Biotechnol ; 49(6)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36370454

RESUMO

2-Phenylethanol (2- PE) is an aromatic alcohol with wide applications, but there is still no efficient microbial cell factory for 2-PE based on Escherichia coli. In this study, we constructed a metabolically engineered E. coli capable of de novo synthesis of 2-PE from glucose. Firstly, the heterologous styrene-derived and Ehrlich pathways were individually constructed in an L-Phe producer. The results showed that the Ehrlich pathway was better suited to the host than the styrene-derived pathway, resulting in a higher 2-PE titer of ∼0.76 ± 0.02 g/L after 72 h of shake flask fermentation. Furthermore, the phenylacetic acid synthase encoded by feaB was deleted to decrease the consumption of 2-phenylacetaldehyde, and the 2-PE titer increased to 1.75 ± 0.08 g/L. As phosphoenolpyruvate (PEP) is an important precursor for L-Phe synthesis, both the crr and pykF genes were knocked out, leading to ∼35% increase of the 2-PE titer, which reached 2.36 ± 0.06 g/L. Finally, a plasmid-free engineered strain was constructed based on the Ehrlich pathway by integrating multiple ARO10 cassettes (encoding phenylpyruvate decarboxylases) and overexpressing the yjgB gene. The engineered strain produced 2.28 ± 0.20 g/L of 2-PE with a yield of 0.076 g/g glucose and productivity of 0.048 g/L/h. To our best knowledge, this is the highest titer and productivity ever reported for the de novo synthesis of 2-PE in E. coli. In a 5-L fermenter, the 2-PE titer reached 2.15 g/L after 32 h of fermentation, suggesting that the strain has the potential to efficiently produce higher 2-PE titers following further fermentation optimization.


Assuntos
Proteínas de Escherichia coli , Álcool Feniletílico , Escherichia coli/genética , Escherichia coli/metabolismo , Álcool Feniletílico/metabolismo , Glucose/metabolismo , Engenharia Metabólica/métodos , Fermentação , Estirenos/metabolismo , Oxirredutases do Álcool/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo
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