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1.
Plants (Basel) ; 13(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38891293

RESUMO

The neglect of Moso bamboo's phenotype variations hinders its broader utilization, despite its high economic value globally. Thus, this study investigated the morphological variations of 16 Moso bamboo populations. The analysis revealed the culm heights ranging from 9.67 m to 17.5 m, with average heights under the first branch ranging from 4.91 m to 7.67 m. The total internode numbers under the first branch varied from 17 to 36, with internode lengths spanning 2.9 cm to 46.4 cm, diameters ranging from 5.10 cm to 17.2 cm, and wall thicknesses from 3.20 mm to 33.3 mm, indicating distinct attributes among the populations. Furthermore, strong positive correlations were observed between the internode diameter, thickness, length, and volume. The coefficient of variation of height under the first branch showed strong positive correlations with several parameters, indicating variability in their contribution to the total culm height. A regression analysis revealed patterns of covariation among the culm parameters, highlighting their influence on the culm height and structural characteristics. Both the diameter and thickness significantly contribute to the internode volume and culm height, and the culm parameters tend to either increase or decrease together, influencing the culm height. Moreover, this study also identified a significant negative correlation between monthly precipitation and the internode diameter and thickness, especially during December and January, impacting the primary thickening growth and, consequently, the internode size.

2.
Molecules ; 29(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731482

RESUMO

An efficient palladium-catalyzed carbonylation of aryl fluorosulfates with aryl formates for the facile synthesis of esters was developed. The cross-coupling reactions proceeded effectively in the presence of a palladium catalyst, phosphine ligand, and triethylamine in DMF to produce the corresponding esters in moderate to good yields. Of note, functionalities or substituents, such as nitro, cyano, methoxycarbonyl, trifluoromethyl, methylsulfonyl, trifluoromethoxy, fluoro, chloro, bromo, methyl, methoxy, N,N-dimethyl, and [1,3]dioxolyl, were well-tolerated in the reactions, which could be kept for late-stage modification. The reactions employing readily available and relatively robust aryl fluorosulfates as coupling electrophiles could potentially serve as an attractive alternative to traditional cross-couplings with the use of aryl halides and pseudohalides as substrates.

3.
Sci Rep ; 14(1): 2686, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302509

RESUMO

Doxorubicin (DOX) is an effective anticancer drug with potent antitumour activity. However, the application of DOX is limited by its adverse reactions, such as depression. Taurine can alleviate depression induced by multiple factors. However, it is still unclear whether and how taurine improves DOX-induced depression. To address this question, the aim of this study was to explore the potential mechanism by which taurine protects against DOX-induced depression. Mice were randomly divided into three groups (n = 8): (1) the control group, (2) the DOX group, and (3) the DOX + taurine group. The open field test (OFT), elevated plus maze test, and forced swim test (FST) were first performed to assess the effects of DOX and taurine on the behaviour of mice. Next, a combined transcriptomic and metabolomic analysis was performed to analyse the possible antidepressive effect of taurine. Taurine pretreatment increased the total distance travelled and speed of mice in the OFT, increased the number of entries into the open arm and the time spent in the open arm, and reduced the immobility time in the FST. In addition, 179 differential genes and 51 differentially abundant metabolites were detected in the DOX + taurine group compared to the DOX group. Furthermore, differential genes and differentially abundant metabolites were found to be jointly involved in 21 pathways, which may be closely related to the antidepressant effect of taurine. Taurine alleviated DOX-induced depressive behaviour. The various pathways identified in this study, such as the serotonergic synapse and the inflammatory mediator regulation of TRP channels, may be key regulatory pathways related to depression and antidepressant effects.


Assuntos
Depressão , Taurina , Camundongos , Animais , Depressão/induzido quimicamente , Depressão/tratamento farmacológico , Depressão/genética , Taurina/metabolismo , Doxorrubicina/toxicidade , Antidepressivos/farmacologia , Perfilação da Expressão Gênica
4.
Molecules ; 29(4)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38398583

RESUMO

Hydroxylation of aryl sulfonium salts could be realized by utilizing acetohydroxamic acid and oxime as hydroxylative agents in the presence of cesium carbonate as a base, leading to a variety of structurally diverse hydroxylated arenes in 47-95% yields. In addition, the reaction exhibited broad functionality tolerance, and a range of important functional groups (e.g., cyano, nitro, sulfonyl, formyl, keto, and ester) could be well amenable to the mild reaction conditions.

5.
Dement Geriatr Cogn Disord ; 53(2): 74-82, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38408448

RESUMO

INTRODUCTION: Previous studies have indicated a correlation between perceived stress and cognitive decline. However, it remains unknown whether high levels of perceived stress can result in motoric cognitive risk (MCR) syndrome. This study investigated the relationship between perceived stress and MCR in a community-based population. METHODS: The study cohort comprised 852 elderly individuals from the Rugao Longitudinal Aging Cohort. Perceived stress was assessed using the 10-item Perceived Stress Scale (PSS-10), while MCR was defined as the coexistence of subjective memory complaints (SMCs) and slow gait speed. RESULTS: The average age of the study participants is 79.84 ± 4.34 years. The mean score of PSS-10 among participants is 10.32 (range = 0-33; [SD] = 5.71), with a median score of 10.00 (6.00, 14.00). The prevalence of MCR is 9.3%. In the logistic regression analysis, for each 1-SD (5.71) increase in the global PSS-10 score, the risk of MCR increased by 40% (95% CI 1.09-1.80). Additionally, in the aspect of two components of MCR, with a 1-SD increase (5.71) in the global PSS-10 score, there was a 50% (95% CI 1.29-1.75) increase in the risk of SMCs and a 27% (95% CI 1.04-1.55) increase in the risk of slow gait speed. In terms of specific walking speed, there was a reverse correlation between the global PSS-10 score and walking speed (r = -0.14, p < 0.001). CONCLUSIONS: This study provided preliminary evidence that high levels of perceived stress were associated with the risk of MCR in a community-dwelling population.


Assuntos
Envelhecimento , Disfunção Cognitiva , Estresse Psicológico , Humanos , Masculino , Idoso , Feminino , Estresse Psicológico/epidemiologia , Estresse Psicológico/psicologia , Idoso de 80 Anos ou mais , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/psicologia , Envelhecimento/fisiologia , Envelhecimento/psicologia , Estudos Longitudinais , Velocidade de Caminhada , Longevidade , Fatores de Risco , Prevalência , Estudos de Coortes , Transtornos da Memória/epidemiologia , Transtornos da Memória/psicologia , Testes Neuropsicológicos
6.
Brain Behav ; 13(12): e3307, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37934082

RESUMO

OBJECTIVE: Compared logistic regression (LR) with machine learning (ML) models, to predict the risk of ischemic stroke in an elderly population in China. METHODS: We applied 2208 records from the Rugao Longitudinal Ageing Study (RLAS) for ischemic stroke risk prediction assessment. Input variables included 103 phenotypes. For 3-year ischemic stroke risk prediction, we compared the discrimination and calibration of LR model and ML methods, where ML methods include Random Forest (RF), Gaussian kernel Support Vector Machines (SVM), Multilayer perceptron (MLP), K-Nearest Neighbors Algorithm (KNN), and Gradient Boosting Decision Tree (GBDT) to develop an ischemic stroke risk prediction model. RESULTS: Age, pulse, waist circumference, education level, ß2-microglobulin, homocysteine, cystatin C, folate, free triiodothyronine, platelet distribution width, QT interval, and QTc interval were significant induced predictors of ischemic stroke. For ischemic stroke prediction, the ML approach was able to tap more biochemical and ECG-related multidimensional phenotypic indicators compared to the LR model, which placed more importance on general demographic indicators. Compared to the LR model, SVM provided the best discrimination and calibration (C-index: 0.79 vs. 0.71, 11.27% improvement in model utility), with the best performance in both validation and test data. CONCLUSION: In a comparison of LR with five ML models, the accuracy of ischemic stroke prediction was higher by combining ML with multiple phenotypes. Combined with other studies based on elderly populations in China, ML techniques, especially SVM, have shown good long-term predictive performance, inspiring the potential value of ML use in clinical practice.


Assuntos
AVC Isquêmico , Humanos , Idoso , Envelhecimento , Algoritmos , China/epidemiologia , Aprendizado de Máquina
7.
Plants (Basel) ; 12(19)2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37836218

RESUMO

The Moso bamboo culm neck, connected with the rhizome and the shoot bud, is an important hub for connecting and transporting the aboveground and belowground systems of bamboo for the shoot bud development and rapid growth. Our previous study revealed that the culm neck generally undergoes six different developmental stages (CNS1-CNS6), according to the primary thickening growth of the underground shoot bud. However, the molecular mechanism of the culm neck development remains unknown. The present study focused on the developmental process of the CNS3-CNS5 stages, representing the early, middle, and late elongation stages, respectively. These stages are densely packed with vascular tissues and consist of epidermis, hypodermis, cortex, and ground tissue. Unlike the hollow structure of the culms, the culm necks are solid structures. As the culm neck continues to grow, the lignin deposition increases noticeably, contributing to its progressive strengthening. For the transcriptome analysis, a total of 161,160 transcripts with an average length of 2373 were obtained from these stages using both PacBio and Illumina sequencing. A total of 92.2% of the reads mapped to the Moso bamboo reference genome. Further analysis identified a total of 5524 novel genes and revealed a dynamic transcriptome. Secondary-metabolism- and transport-related genes were upregulated particularly with the growth of the culm neck. Further analysis revealed the molecular processes of lignin accumulation in the culm neck, which include differentially expressed genes (DEGs) related to cell wall loosening and remodeling and secondary metabolism. Moreover, the upregulations of transcription factors such as MYBH and RSM in the MYB family play crucial roles during critical transitions in the culm neck development, such as changes in the angle between the rhizome and the culm neck. Our new findings provide essential insights into the cellular roadmaps, transcriptional networks, and key genes involved in the culm neck development.

8.
Front Mol Biosci ; 10: 1228771, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37719264

RESUMO

Background: Cold exposure (CE) can effectively modulate adipose tissue metabolism and improve metabolic health. Although previous metabolomics studies have primarily focused on analyzing one or two samples from serum, brown adipose tissue (BAT), white adipose tissue (WAT), and liver samples, there is a significant lack of simultaneous analysis of multiple tissues regarding the metabolic changes induced by CE in mice. Therefore, our study aims to investigate the metabolic profiles of the major tissues involved. Methods: A total of 14 male C57BL/6J mice were randomly assigned to two groups: the control group (n = 7) and the CE group (n = 7). Metabolite determination was carried out using gas chromatography-mass spectrometry (GC-MS), and multivariate analysis was employed to identify metabolites exhibiting differential expression between the two groups. Results: In our study, we identified 32 discriminant metabolites in BAT, 17 in WAT, 21 in serum, 7 in the liver, 16 in the spleen, and 26 in the kidney, respectively. Among these metabolites, amino acids, fatty acids, and nucleotides emerged as the most significantly altered compounds. These metabolites were found to be associated with 12 differential metabolic pathways closely related to amino acids, fatty acids, and energy metabolism. Conclusion: Our study may provide valuable insights into the metabolic effects induced by CE, and they have the potential to inspire novel approaches for treating metabolic diseases.

9.
Org Lett ; 25(34): 6368-6373, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37595017

RESUMO

A chemo-, regio-, and stereoselective reaction of trifluoromethyl enones, phenylsilane, and phosphine oxides through a sequential hydrodefluorination and defluorophosphorylation relay is developed for the synthesis of distinctive gem-fluorophosphine alkenes. This multicomponent reaction occurred under transition-metal-free conditions with good functional group tolerance. Moreover, the preinstalled carbonyl auxiliary is important for tuning the reactivity of ß-trifluoromethyl enones, thereby enabling controllable and selective functionalization of two fluorine atoms in trifluoromethylated enones.

10.
Org Lett ; 25(29): 5525-5529, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37459275

RESUMO

A nickel-catalyzed direct cross-coupling of unactivated aryl fluorides with aryl bromides is realized. The one-pot reaction, which avoids the use of preformed and sensitive organometallic reagents, proceeds effectively via C-F bond cleavage at room temperature in THF in the presence of the phosphine ligand and magnesium powder (with or without TMSCl) to produce the desired biaryls in modest to good yields.

11.
Org Lett ; 25(23): 4388-4393, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37267202

RESUMO

An unprecedented defluorocyclization of perfluorobutyl tetralones with Na2S·9H2O was developed for the synthesis of trifluoromethyl 1,2-dithioles, which provided chemists novel access to biologically and pharmaceutically relevant organofluorides. Successive C(sp3)-F bond functionalization at the perfluoroalkyl chain is vital for the formation of four C-H/C-S/S-S bonds and a five-membered S-heterocycle assembly. Cheap, weakly toxic, and odorless inorganic sulfide Na2S·9H2O acts as both a disulfurating precursor and a hydrodefluorinating reagent in this tandem multi-bond-interconverting reaction.


Assuntos
Tetralonas
12.
Org Lett ; 25(20): 3745-3749, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37167193

RESUMO

The auxiliary function of a carbonyl group in the tunable defluorophosphination and defluorophosphorylation of trifluoromethylated enones with P(O)-containing compounds was demonstrated. Controlled replacement of one or two fluorine atoms in trifluoromethylated enones while maintaining high chemo- and stereoselectivity was achieved under mild conditions, thus enabling diversity-oriented synthesis of skeletally diverse organophosphorus libraries─(Z)-difluoro-1,3-dien-1-yl phosphinates, (1Z,3E)-4-phosphoryl-4-fluoro-buta-1,3-dien-1-yl phosphinates, and (E)-4-phosphoryl-4-fluoro-1,3-but-3-en-1-ones─in good yields with excellent functional group tolerance.

13.
Front Mol Neurosci ; 16: 1146525, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37089694

RESUMO

Objective: Hypertension is a public health challenge worldwide due to its high prevalence and multiple complications. Hypertension-induced damage to the hippocampus leads to behavioral changes and various brain diseases. Despite the multifaceted effects of hypertension on the hippocampus, the mechanisms underlying hippocampal lesions are still unclear. Methods: The 32-week-old spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats were selected as the study subjects. Behavioral experiments such as an open field test (OFT), an elevated plus maze (EPM) test, and the Morris water maze (MWM) test were performed to show the behavioral characteristics of the rats. A comprehensive transcriptomic and metabolomic analysis was performed to understand the changes in the hippocampus at the metabolic and genetic levels. Results: Behavioral tests showed that, compared to WKY rats, SHR showed not only reduced memory capacity but more hyperactive and impulsive behavior. In addition, transcriptomic analysis screened for 103 differentially expressed genes. Metabolomic analysis screened 56 metabolites with significant differences, including various amino acids and their related metabolites. Conclusion: Comprehensive analysis showed that hypertension-induced hippocampal lesions are closely associated with differential metabolites and differential genes detected in this study. The results provide a basis for analyzing the mechanisms of hypertension-induced hippocampal damage.

14.
Org Lett ; 25(10): 1771-1775, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36862539

RESUMO

A straightforward cross-coupling of aryl thioether with aryl bromide with the aid of nickel salt, magnesium, and lithium chloride in tetrahydrofuran at ambient temperature was accomplished. The one-pot reactions proceeded efficiently via C-S bond cleavage to produce the desired biaryls in modest to good yields, avoiding the use of pregenerated or commercial organometallic reagents.

15.
Front Microbiol ; 14: 1143156, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36998405

RESUMO

The genus Bannoa is a small group of ballistoconidium-forming yeasts in the family Erythrobasidiaceae (Cystobasidiomycetes). Prior to this study, seven species belonging to this genus have been described and published. In this study, phylogenetic analyzes of Bannoa based on the combined sequences of the small ribosomal subunit (SSU) rRNA gene, the internal transcribed spacer (ITS) regions, the D1/D2 domains of the large subunit rRNA gene (LSU) and the translation elongation factor 1-α gene (TEF1-α) were conducted. Three new species, namely B. ellipsoidea, B. foliicola, and B. pseudofoliicola, were delimited and proposed based on morphological and molecular evidence. B. ellipsoidea was found to be closely related to the type strains of B. guamensis, B. hahajimensis, and B. tropicalis, but with 0.7-0.9% divergence (4-5 substitutions) in the LSU D1/D2 domains and 3.7-4.1% divergence (19-23 substitutions and one-two gaps) in the ITS regions. B. foliicola was found to belong to the same clade as B. pseudofoliicola from which it differed by 0.4% divergence (two substitutions) in the LSU D1/D2 domains and 2.3% divergence (13 substitutions) in the ITS regions. The distinguishing morphological characteristics of the three new species, with respect to closely related taxa, are discussed. The identification of these new taxa significantly increases the number of Bannoa that have been described on the surface of plant leaves. Additionally, a key for the identification of Bannoa species is provided.

16.
Org Lett ; 25(13): 2318-2322, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-36961113

RESUMO

A one-pot, direct cross-coupling of aryl fluorosulfate with aryl bromide, which is step-economical and avoids the use of a preprepared/commercial organometallic reagent, could be accomplished by performing the reaction in THF at room temperature in the presence of nickel catalyst, magnesium turnings, and lithium chloride, giving rise to the corresponding biaryls in moderate to good yields with reasonable functional group compatibility.

17.
J Stroke Cerebrovasc Dis ; 32(5): 107061, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36871437

RESUMO

BACKGROUND: Neuroinflammation after aneurysmal subarachnoid hemorrhage (aSAH) leads to poor outcome of patients. High mobility group box 1 (HMGB1) contributes to inflammation through binding to receptors for advanced glycation end-products (RAGE) in various diseases. We aimed to determine the production of these two factors after aSAH and their relationship with clinical features. METHODS: HMGB1 and soluble RAGE (sRAGE) levels in cerebrospinal fluid (CSF) of aSAH patients and controls were measured, and their temporal courses were observed. The correlation between early concentrations (days 1-3) and clinical symptoms assessed by disease severity scores, neuroinflammation estimated by CSF IL-6 levels, as well as prognosis evidenced by delayed cerebral ischemia (DCI) and 6-month adverse outcome was investigated. Finally, combined analysis of early levels for predicting prognosis was confirmed. RESULTS: CSF HMGB1 and sRAGE levels were higher in aSAH patients than in controls (P < 0.05), and the levels decreased from higher early to lower over time. Their early concentrations were positively associated with disease severity scores, IL-6 levels, DCI and 6-month poor outcome (P < 0.05). HMGB1 ≥ 6045.5 pg/ml (OR = 14.291, P = 0.046) and sRAGE ≥ 572.0 pg/ml (OR = 13.988, P = 0.043) emerged as independent predictors for DCI, while HMGB1 ≥ 5163.2 pg/ml (OR = 7.483, P = 0.043) and sRAGE ≥ 537.3 pg/ml (OR = 12.653, P = 0.042) were predictors for 6-month poor outcome. Combined analysis of them improved predictive values of adverse prognosis. CONCLUSION: CSF HMGB1 and sRAGE levels of aSAH patients were increased early and then varied dynamically, which might act as potential biomarkers for poor outcome, especially when co-analyzed.


Assuntos
Isquemia Encefálica , Proteína HMGB1 , Hemorragia Subaracnóidea , Humanos , Hemorragia Subaracnóidea/complicações , Interleucina-6 , Doenças Neuroinflamatórias , Prognóstico , Biomarcadores/líquido cefalorraquidiano , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Isquemia Encefálica/etiologia , Isquemia Encefálica/complicações , Infarto Cerebral/complicações
18.
Org Lett ; 24(49): 9086-9091, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36458910

RESUMO

A modular multicomponent reaction of readily available fluoroalkyl alkenes, amidines, ammonium carbonate, and water was developed for the facile construction of ß-fluoroalkylated aminovinyl ketones, which provided chemists a novel access to value-added organofluorine compounds. The reaction proceeded regio-/stereoselectively under mild conditions and exhibited good functional group tolerance. Cheap, stable, and low-toxic inorganic salt (NH4)2CO3 was first found to act as both a nitrogen source and a carbonyl equivalent in the multi-bond-forming process.

19.
Transl Stroke Res ; 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36385451

RESUMO

M1 microglial activation is crucial for the pathogenesis of early brain injury (EBI) following subarachnoid hemorrhage (SAH), and there is growing evidence that glucose metabolism is frequently involved in microglial activation. However, the molecular mechanism of glycolysis and its role in M1 microglial activation in the context of EBI are not yet fully understood. In this study, firstly, the relationship between aerobic glycolysis and M1 microglial activation as well as SAH-induced EBI was researched in vivo. Then, intervention on mammalian target of rapamycin (mTOR) was performed to investigate the effects on glycolysis-dependent M1 microglial activation and EBI and its relationship with hypoxia-inducible factor-1α (HIF-1α) in vivo. Next, Hif-1α was inhibited to analyze its role in aerobic glycolysis, M1 microglial activation, and EBI in vivo. Lastly, both in vivo and in vitro, mTOR inhibition and Hif-1α enhancement were administered simultaneously, and the combined effects were further confirmed again. The results showed that aerobic glycolysis and M1 microglial polarization were increased after SAH, and glycolytic inhibition could attenuate M1 microglial activation and EBI. Inhibition of mTOR reduced glycolysis-dependent M1 microglial polarization and EBI severity by down-regulating HIF-1α expression, while enhancement had the opposite effects. Blockading HIF-1α had the similar effects as suppressing mTOR, while HIF-1α agonist worked against mTOR antagonist when administered simultaneously. In conclusion, the present study showed new evidence that aerobic glycolysis induced by mTOR/HIF-1α might promote EBI after SAH by activating M1 microglia. This finding provided new insights for the treatment of EBI.

20.
Dalton Trans ; 51(40): 15354-15360, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36148531

RESUMO

In this study, we fabricated a novel non-enzymatic glucose sensor based on prism-like bimetallic alkaline carboxylate (CoNi-MIM). The morphology and structure of CoNi-MIM were carefully investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The electrochemical glucose oxidation of the synthesized sensor was then explored by cyclic voltammetry (CV) and chronoamperometry in alkaline medium. It was found that CoNi-MIM is the optimal choice with a remarkably high sensitivity of 5024.4 µA mM-1 cm-2, low detection limit of 56.1 nM (S/N = 3), linear response of up to 14.3 mM and excellent selectivity compared to Co-MIM, CoFe-MIM and CoMn-MIM. Furthermore, the as-fabricated sensor demonstrated appreciable practicality for the determination of glucose in real samples. These results indicate that CoNi-MIM holds a good application prospect in non-enzymatic glucose sensing.


Assuntos
Técnicas Eletroquímicas , Glucose , Catálise , Técnicas Eletroquímicas/métodos , Eletrodos , Glucose/química , Espectroscopia Fotoeletrônica , Pós , Difração de Raios X
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