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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 325: 125154, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39316859

RESUMO

Tracing copper ions levels in the environment and subcellular microenvironment is crucial due to the key role copper ions play in physiological and pathological processes. Herein, a novel naphthalimide-fused rhodamine probe Rh-Naph-Cu was prepared through modification with phenylhydrazine to produce a closed and non-fluorescent spirolactam. Based on the copper-induced spirolactam ring-opening and hydrolysis process, Rh-Naph-Cu can be employed as a fluorescence off-on probe for copper ions with high selectivity, high sensitivity (limit of detection: 33.0 nM), broad pH-response range (pH: 5.0-10.0), and color change visible with the naked eye. Rh-Nap-Cu could be made into test strips for the in-situ chromogenic detection of Cu2+. Significantly, Rh-Naph-Cu can be utilized for the detection of copper ions in living HeLa cells and zebrafish, and exhibits excellent lysosomal-targeting ability with high Pearson's correlation coefficient (PCC) of 0.96.

2.
J Fluoresc ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39320633

RESUMO

Mitochondrial membrane potential (MMP) is crucial for mitochondrial function and serves as a key indicator of cellular health and metabolic activity. Traditional lipophilic cationic fluorescence intensity probes are unavoidably influenced by probe concentration, laser intensity, and photobleaching, limiting their accuracy. To address these issues, we designed and synthesized a pair of fluorescence molecules, OR-C8 and SiR-BA, based on the Förster Resonance Energy Transfer (FRET) mechanism, for dual-modality visualization of MMP. OR-C8 anchors to the inner mitochondrial membrane through strong hydrophobic interactions, while SiR-BA is expelled from mitochondria when MMP decreases, thereby regulating the FRET process. During MMP reduction, the fluorescence intensity and lifetime of OR-C8 increase, while the fluorescence intensity of SiR-BA decreases. By combining changes in fluorescence intensity ratio and fluorescence lifetime, dual-modality visualization of MMP was achieved. This method not only accurately reflects MMP changes but also provides a novel tool for in-depth studies of mitochondrial function and related disease mechanisms, offering significant potential for advancing mitochondrial research and therapeutic development.

3.
Materials (Basel) ; 17(18)2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39336377

RESUMO

In this paper, we demonstrate a method of measuring the flexural elastic modulus of ceramics at an intermediate (~millimeter) scale at high temperatures. We used a picosecond laser to precisely cut microbeams from the location of interest in a bulk ceramic. They had a cross-section of approximately 100 µm × 300 µm and a length of ~1 cm. They were then tested in a thermal mechanical analyzer at room temperature, 500 °C, 800 °C, and 1100 °C using the four-point flexural testing method. We compared the elastic moduli of high-purity Al2O3 and AlN measured by our method with the reported values in the literature and found that the difference was less than 5% for both materials. This paper provides a new and accurate method of characterizing the high-temperature elastic modulus of miniature samples extracted from representative/selected areas of bulk materials.

4.
Expert Opin Drug Metab Toxicol ; : 1-9, 2024 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-39316645

RESUMO

BACKGROUND: The gene polymorphisms of the CYP2C9, as well as the substrate specificity of the enzyme, result in different clearances for different substrates by CYP2C9 variants. RESEARCH DESIGNAND METHODS: The CYP2C9 wild type and 38 CYP2C9 variants, expressed in insectmicrosomes, were incubated with azilsartan. The resulting metabolite,O-desethyl azilsartan, was determined by HPLC-MS/MS. The enzyme kineticparameters of the 38 variants were calculated and compared with the wild type.Subsequently, we selected CYP2C9*1, *2, and *3 as target proteins for molecular docking with azilsartan to elucidate the mechanisms underlying changes in enzyme function. RESULTS: Compared with CYP2C9*1, three variants (CYP2C9*29, *39, and *49) exhibited markedlyincreased CLint values (from 170%-275%, *p < 0.05), whereas 28 variants exhibited significantly decreased CLint values (from 3-63%,*p < 0.05). The molecular docking results showed that the binding energy of CYP2C9*2 and *3 was lower than that of the wild type. CONCLUSION: Thisassessment revealed the effect of CYP2C9 gene polymorphisms on azilsartan metabolism, establishing a theoretical basis for further in-vivo studies and clinical applications. This study will help expand the database of CYP2C9 gene-drug pairs and identify appropriate treatment strategies for azilsartan, contributing to the field of precision medicine.

5.
Inorg Chem ; 63(38): 17914-17920, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39258333

RESUMO

α-Cobalt(II) (CoII) hydroxide (compound 1) incorporating cyanuric acid layers was synthesized via the solvothermal method. 1 exhibited two distinct characteristics, which were different from reported α-CoII hydroxides. (i) The presence of abundant consecutive hydrogen bonds between the adjacent hydroxide layers enhanced the driving force of crystallization along the direction of the c axis. Thus, 1 revealed high crystallinity without the disorder phenomenon. (ii) 1 showed low symmetry. The configuration of CoTd sites did not follow the regular triangular net. The low symmetry favored the magnetic anisotropy. Thus, 1 revealed ferrimagnetic behavior with a high Néel temperature (TN = 56.8 K) and coercivity (Hc = 36 kOe at 2 K). The ferrimagnetic behavior of 1 was validated via the Hubbard U correction density functional theory.

6.
bioRxiv ; 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39257757

RESUMO

One of the most common techniques found in a cell biology or tissue engineering lab is the cytotoxicity assay. This can be performed using a variety of different dyes and stains and various protocols to result in a clear indication of dead and live cells within a culture to quantify the viability of a culture and monitor for sudden drops or increases in viability by a drug, material, viral vector, etc introduced into the culture. This assay helps cell biologists determine the health of their culture and what toxicity added substances may add to the culture and whether they are appropriate and safe to use with human cells. However, many of the dyes and stains used for this process are eventually toxic to cells, rendering the cells useless after testing and preventing real time monitoring of the same culture over a period of hours or days. Computation biology is moving cell biology towards novel and innovative techniques such as in silico labeling and dye free labeling using deep learning algorithms. In this work, we investigate whether it is feasible to train a Resnet CNN model to detect morphological changes in human cells that indicate cell death in order to classify cells as live or dead without utilizing a stain or dye. This work also aims to train one CNN model to count all cells regardless of viability status to get a total cell count, and then one CNN model that specifically identifies and counts all of the dead cells for an accurate dead and live cell total by utilizing both pieces of data to determine a general viability percentage for the culture. Additionally, this work explores the use of various image enhancements to understand if this process helps or impedes the deep learning models in their detection of total cells and dead cells.

7.
Food Chem ; 463(Pt 3): 141401, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39326314

RESUMO

This study comparatively studied the effects of three thermal pretreatment methods, i.e., wet-heat (WT), roasting (RT) and microwave (MT), on the quality attributes and irradiation markers of sesame oil obtained from sesame seeds without and with gamma irradiation. Results showed that gamma irradiation had negligible effect on the quality of sesame seeds and their extracted oils. The effects of thermal pretreatments on irradiated and non-irradiated sesame seeds and their oils were similar, little synergistic effects were observed. The RT-treated oils had more carotenoids, chlorophyll, total phenols, tocopherols, and heterocyclic volatiles content, as well as longer oxidation induction time, but darker color compared with their WT- and MT-treated counterparts. All oil samples had identical FTIR spectra. Eight radiolytic hydrocarbons were identified in the irradiated sesame oils. Thermal pretreatments reduced the content of radiolytic hydrocarbons, but did not significantly change their composition. Our study helps to identify products from irradiated sesame seeds.

8.
Nat Nanotechnol ; 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39327512

RESUMO

The success of personalized cancer immunotherapy depends on the initial tumour antigenic presentation to dendritic cells and macrophages. Tumour-derived extracellular vesicles (TEVs) contain abundant tumour antigenic molecules. The presence of anti-phagocytotic signals such as cluster of differentiation 47 (CD47) on the surface of the TEVs, however, leads to evasion of the same dendritic cells and macrophages. Here we show that iron oxide hydroxide nanocomposites can successfully mask TEV surfaces and unblock phagocytosis without affecting extracellular vesicles' elicited immune goals. After internalization, the mask disintegrates in the lysosome, releasing the tumour antigenic cargo. This triggers antigen presentation and promotes dendritic cell activation and maturation and macrophage reprogramming in animal models, leading to a drastic reduction of tumour volume and metastasis, and in human malignant pleural effusion clinical samples. This straightforward masking strategy eliminates the ubiquitous anti-phagocytosis block found in clinical samples and can be applied universally across all patient-specific TEVs as tumour antigenic agents for enhanced immunotherapy.

9.
Huan Jing Ke Xue ; 45(9): 5298-5307, 2024 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-39323148

RESUMO

To understand the structure of the plankton community and the ecological niche characteristics of their dominant species, sampling surveys of plankton were conducted in Baiyangdian Lake in the spring (March), summer (July), and autumn (September) of 2022. The changes in the plankton community during the three seasons were analyzed by constructing ecological network diagrams, non-metric multidimensional scaling analysis (NMDS), and the ecological niche width. The niche overlap of zooplankton dominant species was evaluated by the improved Levins' formula and Petraitis' index. The interspecific connectivity of dominant species was judged using the chi-square test and interspecies connectivity coefficients. The results showed that the niche width of plankton in the whole area was low. Zooplankton was dominated by rotifers, and phytoplankton was dominated by diatoms, cyanobacteria, and green algae. There were significant seasonal changes in the community structures of plankton. Compared with that in summer and autumn, there were fewer species of plankton in spring and lower interspecies connectivity. The overlap of dominant species of zooplankton was high in summer, and the interspecific competition was intensified, whereas the interspecific overlap of phytoplankton was at a low level in all three seasons. There was a significant positive correlation (W > χ20.05) between phytoplankton in summer and autumn, and the community structure was stable. The interdomain ecological network of zooplankton and phytoplankton showed a high negative correlation ratio in autumn, especially between copepods and cladoceras of zooplankton and chlorophyta and cyanophyta of phytoplankton. The plankton species in Baiyangdian Lake were abundant, with obvious seasonal differences. The dominant species were mainly a narrow ecological niche. The plankton community was generally in a stable state, and there was a strong predation relationship between copepods and cladoceras and green algae and cyanobacteria.


Assuntos
Ecossistema , Lagos , Fitoplâncton , Estações do Ano , Zooplâncton , China , Zooplâncton/classificação , Fitoplâncton/classificação , Fitoplâncton/crescimento & desenvolvimento , Animais , Plâncton/classificação , Dinâmica Populacional , Monitoramento Ambiental/métodos , Cianobactérias/crescimento & desenvolvimento , Rotíferos/fisiologia , Rotíferos/crescimento & desenvolvimento , Diatomáceas/crescimento & desenvolvimento
10.
J Biol Chem ; : 107828, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39341499

RESUMO

The connection between SARS-CoV-2 replication-transcription complexes (RTCs) and nucleocapsid (N) protein is critical for regulating genomic RNA replication and virion packaging over the viral life cycle. However, the mechanism that dynamically regulates genomic RNA packaging and replication remains elusive. Here, we demonstrate that the N-terminal domain (NTD) of SARS-CoV-2 nonstructural protein 3 (Nsp3), a core component of viral RTCs, binds N protein and displaces RNA in a concentration-dependent manner. This interaction disrupts liquid-liquid phase separation of N protein driven by N protein-RNA interactions which is crucial for virion packaging and viral replication. We also report a high-resolution crystal structure of the Nsp3 ubiquitin-like domain 1 (Ubl1) at 1.49 Å, which reveals abundant negative charges on the protein surface. Sequence and structural analyses identify several conserved motifs at the Ubl1-N protein interface and a previously unexplored highly negative groove, providing insights into the molecular mechanism of Ubl1-mediated modulation of N protein-RNA binding. Our findings elucidate the mechanism of dynamic regulation of SARS-CoV-2 genomic RNA replication and packaging over the viral life cycle. Targeting the conserved Ubl1-N protein interaction hotspots also promises to aid in the development of broad-spectrum antivirals against pathogenic coronaviruses.

11.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 49(6): 921-931, 2024 Jun 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-39311788

RESUMO

OBJECTIVES: Chronic obstructive pulmonary disease (COPD) is a significant global public health issue. Modern medical treatments have both benefits and limitations, prompting increasing attention from scholars worldwide on traditional ethnic medicine, and the Zangsiwei Qingfei Mixture is a newly developed formula derived from the effective components of classical Tibetan medicine to treat chronic respiratory diseases. This study aims to investigate the clinical efficacy and safety of the Zangsiwei Qingfei Mixture combined with conventional treatment in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). METHODS: Sixty AECOPD patients admitted to the Second Xiangya Hospital of Central South University from May 2021 to May 2023 were enrolled and randomly divided into 2 groups, with 30 patients in each group. The control group received conventional treatment, including bronchodilators, anti-infection agents, expectorants, and oxygen therapy. The experimental group received the Zangsiwei Qingfei Mixture in addition to conventional treatment. The treatment duration was 7 d for both groups. Baseline data such as gender, age, body mass index (BMI), smoking status, Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification, COPD course, and the number of COPD exacerbations in the past year were collected. The primary efficacy indicators were assessed using the modified Medical Research Council (mMRC) dyspnea scale and the modified Borg scale. Secondary indicators included arterial lactic acid (LAC) and serum tumor necrosis factor alpha (TNF-α) levels. Safety indicators included liver and kidney function [alanine transaminase (ALT), aspartate transaminase (AST), serum creatinine (SCr), serum uric acid (SUA)], coagulation function [activated partial thromboplastin time (APTT), prothrombin time (PT), fibrinogen (FIB), and D-dimer]. The generalized linear mixed model (GLMM) was used to evaluate the clinical efficacy and safety of the Zangsiwei Qingfei Mixture. RESULTS: Before treatment, there were no statistically significant differences in general baseline data, grading of mMRC dyspnea scale, score of modified Borg scale, arterial LAC, ALT, AST, SCr, SUA, APTT, FIB, and D-dimer between the 2 groups (all P>0.05). However, serum TNF-α and PT levels in the experimental group were significantly lower than those in the control group (both P<0.05). GLMM analysis showed that after adjusting for pre- and post-treatment, gender, age, BMI, smoking status, GOLD classification, COPD course, and the number of COPD exacerbations in the past year, the experimental group demonstrated significantly lower grading of mMRC dyspnea scale (coefficient=-0.329, P=0.036), score of modified Borg scale (coefficient=-1.077, P=0.001), serum TNF-α level (coefficient=-14.378, P<0.001), and arterial LAC level (coefficient=-0.409, P=0.012) compared to the control group. The Zangsiwei Qingfei Mixture had no significant effect on liver, kidney, or coagulation function indicators (all P>0.05). CONCLUSIONS: The Zangsiwei Qingfei Mixture combined with conventional treatment can improve clinical symptoms and promote homeostasis in AECOPD patients, demonstrating safety and reliability. Combining modern medicine with traditional ethnic medicine offers a feasible approach to treating chronic respiratory diseases in the future.


Assuntos
Medicamentos de Ervas Chinesas , Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Masculino , Feminino , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/efeitos adversos , Resultado do Tratamento , Medicina Tradicional Chinesa/métodos , Idoso , Pessoa de Meia-Idade
12.
Zhongguo Zhong Yao Za Zhi ; 49(15): 4069-4077, 2024 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-39307739

RESUMO

This study investigates the therapeutic effect of hybrid exosomes loaded with sinomenine(SIN) obtained by membrane fusion of milk exosomes with liposomes in collagen-induced arthritis(CIA) rats. Exosomes were isolated from fresh bovine milk by sucrose density gradient centrifugation, while liposomes were prepared using the emulsion solvent evaporation-low temperature curing method. Hybrid exosomes were characterized after membrane fusion through co-incubation: The morphology was detected by transmission electron microscopy, the particle size and potential by nanoparticle size potentiostat, and the expressions of surface characteristic proteins CD63 and TSG101 before and after fusion by Western blot(WB). The drug loading capacity and encapsulation rate of sinomenine were measured after the loading of sinomenine on exosomes by ultrasonic method. The CIA rat model was induced by collagen antibody. The efficacy experiment consisted of the control group, model group, SIN group, SIN-liposome group, SIN-milk exosome group, SIN-hybrid exosome group and positive drug(dexamethasone) group. The changes in body mass of rats during administration were recorded. Besides, the foot swelling, immune organ index, arthritis index, microcirculation index, synovial histopathology, and serum inflammatory factor levels detected by enzyme-linked immunosorbent assay were observed for pharmacodynamical study. Under transmission electron microscopy, both hybrid exosomes and milk exosomes showed saucer-like appearance. After co-incubation, the exosome particle size increased from(97.92±3.42)nm to(132.70±4.07)nm, and the Zeta potential changed from(-2.01±0.33)mV to(-17.90±2.13)mV. WB assay showed that CD63 and TSG101 proteins were normally expressed in milk exosomes and hybrid exosomes. The encapsulation rate of milk exosomes was 31.64%±2.48%, with a drug loading of 2.35%±0.52%, while the hybrid exosomes exhibited an encapsulation rate of 48.21%±3.12% and drug loading of 3.17%±0.36%, as determined by the microplate reader. Pharmacodynamic results showed that compared with the model group, the general condition, swelling degree of foot, arthritis index and immune organ index of all drug administration groups were significantly improved(P<0.05, P<0.01); microvascular comprehensive score and vascular resistance were significantly decreased(P<0.05, P<0.01); serum levels of TNF-α, IL-1ß and IL-6 inflammatory factors were significantly decreased(P<0.01); and the lesions of synovial tissue were improved to some extent. Meanwhile, compared with the SIN group, SIN-liposome group and SIN-milk exosome group, the SIN-hybrid exosome group had a more stable and durable drug effect. The hybrid exosomes obtained by co-incubation of milk-derived exosomes with liposomes successfully improved the drug carrying capacity of exosomes and biocompatibility of liposomes. The hybrid exosomes loaded with sinomenine have good efficacy on CIA model rats, and can effectively solve the problems of TCM such as sinomenine, which have good efficacy but short biological half-life. The study provides new insights for the development of TCM and the treatment of diseases such as rheumatoid arthritis.


Assuntos
Artrite Reumatoide , Exossomos , Lipossomos , Leite , Morfinanos , Animais , Exossomos/química , Ratos , Lipossomos/química , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Leite/química , Bovinos , Morfinanos/química , Morfinanos/administração & dosagem , Morfinanos/farmacologia , Masculino , Humanos , Feminino
13.
Elife ; 132024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39292605

RESUMO

Bumblebees (Bombus terrestris) have been shown to engage in string-pulling behavior to access rewards. The objective of this study was to elucidate whether bumblebees display means-end comprehension in a string-pulling task. We presented bumblebees with two options: one where a string was connected to an artificial flower containing a reward and the other presenting an interrupted string. Bumblebees displayed a consistent preference for pulling connected strings over interrupted ones after training with a stepwise pulling technique. When exposed to novel string colors, bees continued to exhibit a bias towards pulling the connected string. This suggests that bumblebees engage in featural generalization of the visual display of the string connected to the flower in this task. If the view of the string connected to the flower was restricted during the training phase, the proportion of bumblebees choosing the connected strings significantly decreased. Similarly, when the bumblebees were confronted with coiled connected strings during the testing phase, they failed to identify and reject the interrupted strings. This finding underscores the significance of visual consistency in enabling the bumblebees to perform the task successfully. Our results suggest that bumblebees' ability to distinguish between continuous strings and interrupted strings relies on a combination of image matching and associative learning, rather than means-end understanding. These insights contribute to a deeper understanding of the cognitive processes employed by bumblebees when tackling complex spatial tasks.


Assuntos
Compreensão , Animais , Abelhas/fisiologia , Compreensão/fisiologia , Flores/fisiologia , Comportamento Animal/fisiologia , Recompensa
15.
Protein Cell ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39252612

RESUMO

Pyroptosis is an identified programmed cell death that has been highly linked to endoplasmic reticulum (ER) dynamics. However, the crucial proteins for modulating dynamic ER membrane curvature change that trigger pyroptosis are currently not well understood. In this study, a biotin-labeled chemical probe of potent pyroptosis inducer α-mangostin (α-MG) was synthesized. Through protein microarray analysis, reticulon-4 (RTN4/Nogo), a crucial regulator of ER membrane curvature, was identified as a target of α-MG. We observed that chemically induced proteasome degradation of RTN4 by α-MG through recruiting E3 ligase UBR5 significantly enhances the pyroptosis phenotype in cancer cells. Interestingly, the downregulation of RTN4 expression significantly facilitated a dynamic remodeling of ER membrane curvature through a transition from tubules to sheets, consequently leading to rapid fusion of the ER with the cell plasma membrane. In particular, the ER-to-plasma membrane fusion process is supported by the observed translocation of several crucial ER markers to the "bubble" structures of pyroptotic cells. Furthermore, α-MG-induced RTN4 knockdown leads to PKM2-dependent conventional caspase-3/GSDME cleavages for pyroptosis progression. In vivo, we observed that chemical or genetic RTN4 knockdown significantly inhibited cancer cells growth, which further exhibited an antitumor immune response with anti-PD-1. In translational research, RTN4 high expression was closely correlated with the tumor metastasis and death of patients. Taken together, RTN4 plays a fundamental role in inducing pyroptosis through the modulation of ER membrane curvature remodeling, thus representing a prospective druggable target for anticancer immunotherapy.

16.
J Multidiscip Healthc ; 17: 4243-4256, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39228515

RESUMO

Background: Clinical acupuncture decisions are highly operator-dependent and require physician-patient interactions. The Delphi method allows subjective factors such as expert experience and preference of patients to be taken into account in clinical decision making, which is particularly applicable to acupuncture. Currently, the Delphi method is widely used to support clinical decisions in acupuncture. Therefore, it is necessary to provide high-quality and complete descriptions of the Delphi process when making clinical decisions. This study aims to evaluate the quality of the Delphi process in acupuncture, facilitate its standardization and rigor for further clinical decision making in acupuncture. Methods: Articles sourced from six databases were searched systematically to assess the quality of the Delphi consensus process based on the standards for conducting and reporting Delphi studies (CREDES). Descriptive statistics and analysis were presented according to the percentage of each item. Five-score Likert scale was used to evaluate the reporting quality of four domains as well as each item in CREDES by two independent researchers, combined with ICC-value to assess the consistency. Results: A total of 37 qualified articles were included according to eligibility criteria. As for the low reporting rate, the item "External validation" was reported as the lowest positive rate at 32.43% and the item "Prevention of bias" was 48.65%. The item "Adequacy of conclusions", "Definition and attainment of consensus", and "Discussion of limitations" were reported at a positive ratio of 62.16%, 64.86%, and 67.57% individually. The average scores of the four domains based on CREDES from highest to lowest were, respectively, as follows: planning and design (68.75%), reporting (66.07%), rationale for the choice of the Delphi technique (65.54%), study conduct (45.10%). Conclusion: The reporting quality of the Delphi consensus process in acupuncture is acceptable currently, but the reporting rate on some items is still low. Further standardization, including either clearer checklists or study reports, should be developed and strengthened to guide clinical decisions in acupuncture.

17.
Chem Commun (Camb) ; 60(75): 10390-10393, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39224044

RESUMO

A new Ru-catalyzed C-H activation/cyclization reaction for the synthesis of 3-C-glycosyl isocoumarins and 2-glycosyl-4H-chromen-4-ones with carbonyl sulfoxonium ylide glycogen are reported. In this catalytic system, benzoic acid and its derivatives react with carbonyl sulfoxonium ylide glycogen to yield isocoumarin C-glycosides, while 2-hydroxybenzaldehyde substrates react to produce chromone C-glycosides. These reactions were characterized by mild reaction conditions, broad substrate scope, high functional-group compatibility, and high stereoselectivity to yield several high-value isocoumarins and chromone skeleton-containing C-glycosides. The methods were successfully implemented in the context of large-scale reactions and the late-stage modification of complex natural products.

18.
Macromol Rapid Commun ; : e2400616, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39240251

RESUMO

With the rapid development of information technology (e.g., Internet of Things (IoT) and artificial intelligence (AI)), piezoelectric sensor (i.e., piezoelectric nanogenerator, PENG) receives an increasing number attention in the field of self-powered wearable devices. Taking piezoelectric fiber as an example, it shows promising application for wearable devices owing to its light weight and high flexibility compared with block electronic devices. However, it still remains a challenge to fabricate low-cost and high-performance piezoelectric fiber via a large-scale but efficient method. In this study, via extrusion molding and leaching, a core-sheath piezoelectric sensor is facilely fabricated, whose core and sheath layer are respectively slender steel wire (i.e., electrode) and PVDF microfibrillar bundle (PMB) (i.e., piezoelectric layer). Such piezoelectric sensor shows decent output performance in both pressing (12.3 V) and bending (0.32 V) mode. Meanwhile, it possesses sensitive stress responsiveness when serving for self-powered sensing. Furthermore, such piezoelectric sensors can realize wearable signal transmission and human motion monitoring, showing promising potential for wearable devices in the future. This work proposes a large-scale but efficient method for fabricating high-performance PVDF microfibril based piezoelectric fiber, opening a new pathway to develop self-powered sensors following the concept of polymer "structuring" processing.

19.
Ying Yong Sheng Tai Xue Bao ; 35(7): 1959-1967, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39233426

RESUMO

The dynamics of soil arthropod communities in annual monoculture grasslands is still unclear, which restricts the understanding of the degradation mechanism of cultivated grasslands. We cultivated two annual gramineae species, Lolium multiflorum and Avena sativa, separately in Hongyuan County, located on the eastern edge of the Qinghai-Tibet Plateau, in April 2019. We investigated soil arthropods, plant communities and soil properties in the cultivated grasslands and natural grassland in the late September every year from 2019 to 2022. The results showed that: 1) The taxonomic composition of soil arthropod communities differed significantly among three grasslands and sampling years. 2) There was no significant difference in the density, taxonomic richness, Shannon index and evenness index of soil arthropod communities among three grasslands. 3) The density of soil arthropod communities significantly fluctuated across years in three grasslands, and the taxonomic richness and Shannon index decreased significantly in the L. multiflorum and A. sativa grasslands, with the evenness index declining significantly only in the fourth year. The Shannon index fluctuated significantly and the evenness index varied little in natural grassland. 4) The above- and below-ground biomass, the contents of soil total P, total K and available N were the main factors influencing the taxonomic composition, density and diversity indices of soil arthropod communities. The results suggested that the cultivation of annual gramineae grasslands have significant effects on taxonomic composition, but not on density and diversity of soil arthropod communities, and those variables change significantly across different years.


Assuntos
Artrópodes , Pradaria , Solo , Animais , Artrópodes/classificação , Artrópodes/crescimento & desenvolvimento , Solo/química , China , Biodiversidade , Dinâmica Populacional , Lolium/crescimento & desenvolvimento , Lolium/classificação , Poaceae/crescimento & desenvolvimento , Poaceae/classificação , Avena/crescimento & desenvolvimento , Avena/classificação , Altitude
20.
Diabetes Obes Metab ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39233493

RESUMO

AIM: Diabetic cognitive impairment (DCI), considered one of the most severe and commonly overlooked complications of diabetes, has shown inconsistent findings regarding the metabolic profiles in DCI patients. This systematic review and meta-analysis aimed to identify dysregulated metabolites as potential biomarkers for early DCI, providing valuable insights into the underlying pathophysiological mechanisms. MATERIALS AND METHODS: A systematic search of four databases, namely PubMed, Embase, Web of Science and Cochrane, was conducted up to March 2024. Subsequently, a qualitative review of clinical studies was performed followed by a meta-analysis of metabolite markers. Finally, the sources of heterogeneity were explored through subgroup and sensitivity analyses. RESULTS: A total of 774 unique publications involving 4357 participants and the identification of multiple metabolites were retrieved. Of these, 13 clinical studies reported metabolite differences between the DCI and control groups. Meta-analysis was conducted for six brain metabolites and two metabolite ratios. The results revealed a significant increase in myo-inositol (MI) concentration and decreases in glutamate (Glu), Glx (glutamate and glutamine) and N-acetylaspartate/creatine (NAA/Cr) ratios in DCI, which have been identified as the most sensitive metabolic biomarkers for evaluating DCI progression. Notably, brain metabolic changes associated with cognitive impairment are more pronounced in type 2 diabetes mellitus than in type 1 diabetes mellitus, and the hippocampus emerged as the most sensitive brain region regarding metabolic changes associated with DCI. CONCLUSIONS: Our results suggest that MI, Glu, and Glx concentrations and NAA/Cr ratios within the hippocampus may serve as metabolic biomarkers for patients with early-stage DCI.

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