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Carbon dots (CDs) are the most promising members of the carbon family with superior properties such as ultrasmall size, high solubility, low cytotoxicity, and inherent fluorescence endows their potential for diverse applications. There are several discovered methods to improve their properties and the extent of their applications. Possible approaches are doping or surface passivation of CDs to enhance their properties, visible light absorption, and quantum yields by controlling their size, morphology, structure, and band gap energy. As an efficient method to improve the intrinsic properties of carbon dots, doping CDs with heteroatoms such as nonmetallic and metallic atoms has received increasing attention from researchers around the globe. Recently, metal ions doped-carbon dots (M-CDs) have emerged as an important one of nanomaterials with numerous applications. In this paper, we will summarize the state-of-the-art knowledge of M-CDs. The synthetic methods for M-CDs, the novel physicochemical properties originating from the doping of metal ions, and their applications in chemical sensing, biological imaging, phototherapy, optoelectronics, and catalysis will also be highlighted. Furthermore, we will describe challenges in preparing M-CDs and an outlook for their future development.

This article proposes a solution to improve office chairs (referred to as IoT chairs) based on IoT technology and LSTM (Long Short – Term Memory) neural networks to monitor and promptly warn via the Internet about questions of abnormal health status of office staff. An IoT circuit with the MCU-ESP8266 module is used to collect weight and an accelerometer sensor embedded in the chair, which can communicate with a computer to monitor the searing time of the user and warn by sound for prolonged sitting. LSTM neural networks built on MATLAB is trained by deep learning techniques to track inappropriate postures of people sitting in chairs, through analyzing signals from sensors. Experiment results on many different scenarios show that the accuracy of capacity of reminding about the status of prolonged sitting is 100% and reliability of the capacity of detecting and warning abnormal health conditions is 94%. Experiments also show that the ability to complete IoT chairs for a popular application is completely feasible.

Bài báo này trình bày phương pháp thiết kế bộ điều khiển trượt dựa vào bộ quan sát nhiễu và chế độ Quasi hệ thống bồn đôi tương tác. Điều khiển mức chất lỏng trong một hệ thống bồn chứa là sự quan tâm lớn trong các ngành công nghiệp chế biến như dầu khí, nhà máy lọc dầu, hóa chất, công nghiệp giấy, các ngành công nghiệp xử lý nước. Bộ điều khiển trượt đảm bảo vị trí mức chất lỏng thực tế bám theo vị trí mong muốn trong thời gian hữu hạn. Bộ quan sát nhiễu sẽ ước lượng nhiễu và thành phần không chắc chắn và phương pháp bù sẽ được thực hiện trong điều khiển hồi tiếp. Chế độ trượt Quasi được sử dụng để khắc phục hiện tượng chattering trong điều khiển trượt. Các kết quả mô phỏng với MATLAB/Simulink cho thấy hiệu quả của bộ điều khiển đề xuất và được so sánh với bộ điều khiển mờ, PID-mờ, điều khiển thích nghi mô hình tham chiếu tối ưu mờ dựa vào các luật Lyapunov và điều khiển trượt sử dụng tích hợp điều kiện với độ vọt lố là 0(%), thời gian tăng đạt 0,3183(s), thời gian xác lập là 0,5102(s) và sai số xác lập bị triệt tiêu.

Ten phenolic constituents, including three new macrocyclic glycosides (

Elaeocarpus hygrophilus Kurz. is a tropical tree that has recently been used for food and medicinal purposes. This study aimed to reveal the phytochemicals and evaluate the anti-influenza viral and neuroprotective effects of different parts of this plant including leaves, stems, fruit peels, and seeds. The study results indicated that the leaf extract was a potential candidate in the inhibition of the influenza viral replication through anti-neuraminidase receptors and attenuation of the glutamate-induced neuronal cell death and cellular oxidative stress. Using molecular networking as well as fragmentation, twenty-six known compounds were dereplicated from the leaves of E. hygrophilus. Molecular docking simulations of target proteins (PDB: 3CL0 and 4CXT) with these predicted compounds indicated that phenolic compounds from the EtOH leaf extract may be considered as active components for treating not only neuraminidase inhibitor-resistant strains but also activating Keap1/Nrf2 pathway. The anti-influenza viral and neuroprotective effects of the leaf extract and the link between the two activities could significantly contribute to the development of natural product drugs for influenza treatment and prevention of neuropsychiatric adverse events. These results suggested further research about the phytochemicals and the bio-guided isolation of the most active fractions from the leaf extract and their respective herbal drug formulations, with effective and secure aspects, to low-income populations of the tropics.

Chemical investigation of the plant Gymnema latifolium led to the isolation of seven undescribed 23-glycosyl oleanane triterpenoids, gymlatinosides GLF1-GLF7, and two known compounds, gymnemosides D and E. The structures of the isolated compounds were elucidated using diverse spectroscopic methods. The extract of G. latifolium and all isolated compounds significantly enhanced 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxyglucose (2-NBDG) uptake into 3T3-L1 adipocytes at 20 μM. Among them, gymlatinosides GLF2 and gymlatinosides GLF4 showed particularly potent stimulatory effects on glucose uptake in a dose-dependent manner. Further investigation revealed that gymlatinosides GLF2 at 20 μM upregulated the expression of phosphorylated AMPK (p-AMPK). The results suggested that gymlatinosides GLF2 may enhance glucose uptake via regulating the AMPK signaling pathway.

With the advent of senolytic agents capable of selectively removing senescent cells in old tissues, the perception of age-associated diseases has been changing from being an inevitable to a preventable phenomenon of human life. In the search for materials with senolytic activity from natural products, six new flavonostilbenes (1-6), three new phenylethylchromanones (7-9), three new phenylethylchromones (10-12), and four known compounds (13-16) were isolated from the roots of Rhamnoneuron balansae. The chemical structures of these isolated compounds were determined based on the interpretation of spectroscopic data, including 1D and 2D NMR, ECD, and HRMS. The absolute configuration of compound 1 was also determined by a Mosher ester analysis and ECD calculations. Compounds 6-8 were shown to selectively destroy senescent cells, and the promoter activity of p16INK4A, a representative senescence marker, was reduced significantly by compound 6. The present results suggest the potential activity of flavonostilbene and phenylethylchromanone skeletons from R. balansae as new senolytics.

The therapeutic efficacy of current cancer vaccines is far from optimal, mainly because of insufficient induction of antigen-specific T cells and because tumor cells can hijack immunosuppressive mechanisms to evade the immune responses. Generating specific, robust, and long-term immune responses against cancer cells and the attenuating of immunosuppressive factors are critical for effective cancer vaccination. Recently, the engineering of exosomes specifically bind to T cells, and then stimulating tumor-specific T-cell immune responses has emerged as a potential alternative strategy for cancer vaccination. In this study, we generated a bifunctional exosome combining the strategy of vaccination and checkpoint blockade. Exosomes prepared from Ovalbumin (OVA)-pulsed, activated dendritic cells were modified with anti-CTLA-4 antibody (EXO-OVA-mAb) to block this inhibitory molecule and to enhance the specificity of the exosomes toward T cells. Our study provides a unique strategy for functionalizing exosome membrane with anti-CTLA-4 antibody via lipid-anchoring method to synergize efficacy of cancer vaccination and immune checkpoint blockade against the tumor. Statement of Significance We designed T-cell-targeting exosomes (EXO-OVA-mAb) decorated with costimulatory molecules, MHCs, antigenic OVA peptide, and anti-CTLA-4 antibody, combining the strategies of vaccines and checkpoint blockade. The exosomes showed enhanced binding to T cells in tumor-draining lymph nodes, effectively induced T-cell activation, and improved the tumor homing of effector T cells, ultimately significantly restraining tumor growth. Thus, EXO-OVA-mAb greatly facilitates T-cell targeting, induces a strong tumor-specific T-cell response, and increased the ratio of effector T cells/regulatory T cells within tumors, resulting in appreciable tumor growth inhibition.

During an effort to find insulin mimetic compounds, the leaves of Gymnema inodorum were shown to have a stimulatory effect on glucose uptake in 3T3-L1 adipocyte cells. Bioassay-guided fractionation on a 70% ethanol extract of G. inodorum was applied to yield two new (1 and 2) and two known (8 and 9) oleanane triterpenoids with a methyl anthranilate moiety together with five further new oleanane triterpenoids (3-7). The chemical structures of all isolates were determined based on their spectroscopic data, including IR, UV, NMR, and mass spectrometric analysis. The isolated compounds (1-9) were determined for their stimulatory activities on glucose uptake in differentiated 3T3-L1 adipocyte cells using 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-d-glucose (2-NBDG) as a fluorescent-tagged glucose probe. Three compounds (3, 5, and 9) showed stimulatory effects on the uptake of 2-NBDG in 3T3-L1 adipocyte cells. Chemicals with a methyl anthranilate moiety have been considered as crucial contributors of flavor odor in foods, and quantitative analysis showed the content of compound 8 to be 0.90 ± 0.01 mg/g of the total extract. These results suggest that the leaves of G. inodorum have the potential to be used as an antidiabetic functional food or tea.

The major class of bioactive metabolites in Gymnema sylvestre, a popular Ayurvedic medicinal plant for the treatment of diabetes mellitus, is oleanane triterpenoids. In this study, a targeted, biosynthesis-inspired approach using UHPLC-qTOF/MS was implemented to elucidate the whole chemical profile of this plant for the standardization of the Vietnamese G. sylvestre variety. The known compounds were first determined to identify the building blocks of the biosynthetic intermediates and the construction rules for synthesizing oleanane triterpenoids in the plant. These blocks were recombined to build a virtual library of all reasonable compounds consistent with the deduced construction rules. Various techniques, including relative mass defect filtering, multiple key ion analysis, mass fragmentation analysis, and comparison with standard references, were applied to determine the presence of these predicted compounds. Conventional isolation and structure elucidation of six of the new compounds were carried out to identify the new building blocks and validate the assignments. Consequently, 119 peaks were quickly assigned to oleanane triterpenoids, and among them, 77 peaks were predicted to be new compounds based on their molecular formulas and mass fragmentation patterns. All the identified metabolites were then classified into different layers to analyze their logical relationships, and a multilayered chemical profile of the oleanane triterpenoids was constructed. This new approach is expected to be practical for characterizing structures of modular secondary metabolites, such as triterpenoid saponins, and for proposing biosynthetic relationships among compounds of the same class of metabolites in medicinal plants.

Ten phenolic constituents, including three new macrocyclic glycosides (1–3), a new phenolic glycoside (5), a new biphenyl glycoside (6), and five known compounds (4, 7–10), were isolated from a 70% MeOH extract of the leaves of Heliciopsis terminalis by liquid chromatography-tandem mass spectrometry (LC-MS/MS)-guided molecular networking. The chemical structures of new compounds 1–3, 5 and 6 were established based on comprehensive spectroscopic data analysis, including 1D and 2D NMR and HRESIMS techniques. All isolated compounds (1–10) were evaluated for their stimulation of glucose uptake in differentiated 3T3-L1 adipocytes using 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-d-glucose (2-NBDG) as a fluorescent glucose analog. Compounds 3, 6 and 8 showed stimulatory effects on the uptake of 2-NBDG in 3T3-L1 adipocyte cells. Among them, compounds 3 and 6 activated the AMPK signaling pathway in differentiated C2C12 myoblasts.

Bioassay-guided fractionation of the 80% ethanol extract of Gynostemma compressum X. X. ChenD. R. Liang (Cucurbitaceae) resulted in the isolation and identification of eight undescribed triterpenoids, gycomol VN1, gycomol VN2, and gycomosides VN1-6 from the bioactive n-butanol fraction. The structures of these compounds were elucidated by one- and two-dimensional nuclear magnetic resonance spectroscopy, high-resolution electrospray ionisation mass spectrometry, and chemical methods. All isolated compounds were evaluated for their 5'-adenosine monophosphate-activated protein kinase (AMPK) and acetyl-coenzyme A carboxylase (ACC) activation effects on 3T3-L1 cells. Importantly, gycomol VN2, gycomoside VN1, and gycomosides VN3-5 activated the phosphorylation of AMPK and its downstream substrate ACC in 3T3-L1 cells at a dose of 10 μM. These effects imply that the activation of AMPK and ACC by active compounds from G. compressum has considerable potential for the prevention of obesity and its related disorders by activating AMPK signaling pathways.

Melicope pteleifolia has long been consumed as a popular vegetable and tea in Southeast Asian countries, including Malaysia and southern mainland China, and is effective in the treatment of colds and inflammation. In the search for active metabolites that can explain its traditional use as an antipyretic, six new phloroacetophenone derivatives (3-8) along with seven known compounds (1, 2, and 9-13) were isolated from the leaves of M. pteleifolia. Their chemical structures were confirmed by extensive spectroscopic analysis including NMR, IR, ECD, and HRMS. All compounds isolated from the leaves of M. pteleifolia (1-13) have a phloroacetophenone skeleton. Notably, the new compound 8 contains an additional cyclobutane moiety in its structure. The bioactivities of the isolated compounds were evaluated, and compounds 1, 6, and 7 inhibited tumor necrosis factor-α-induced prostaglandin E2. Moreover, the major constituent, 3,5-di-C-β-d-glucopyranosyl phloroacetophenone (1), was found to be responsible for the antipyretic activity of M. pteleifolia based on in vivo experiments.

As part of an ongoing study of new insulin mimetic agents from medicinal plants, the 70% EtOH extract of Symplocos cochinchinensis was found to have a stimulatory effect on glucose uptake in 3T3-L1 adipocyte cells. The intensive targeted isolation of this active extract resulted in ten new hydroxyoleoside-type compounds conjugated with a phenolic acid and monoterpene (1–6 and 8–11), as well as four known compounds (7 and 12–14). The chemical structures of the new compounds were determined based on spectroscopic data analysis (1H and 13C NMR, HSQC, HMBC, NOESY and MS). The absolute configurations of the isolated compounds were determined by electronic circular dichroism (ECD) analysis of derivatives obtained after a series of reactions, such as those with dirhodium (ІІ) tetrakis (trifluoroacetate) and dimolybdenum (ІІ) tetraacetate. In vitro, compounds 3, 7 and 8 moderately increased the 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-D-glucose (2-NBDG) uptake level in differentiated 3T3-L1 adipocytes. For further studies, we evaluated their effects on the expression of glucose transporter-4 (GLUT4), its translocation, protein tyrosine phosphatase 1B (PTP1B) inhibition and expression of phosphorylated Akt. Our results strongly suggest that the traditional uses of this plant can be described as active constituents by hydroxyoleoside-type compounds.

A library of extracted natural materials (Korea Bioactive Natural Material Bank) have been screened to discover candidates for the treatment of non-alcoholic liver disease (NAFLD), and the 70% ethanol extract of Sicyos angulatus was found to inhibit hepatic lipid accumulation. Bioassay–guided fractionation of this bioactive extract yielded five previously undescribed flavonoid glycosides and one previously undescribed flavonolignan glycoside along with seven known flavonoid glycosides. The chemical structures of these compounds were elucidated by a combination of extensive spectroscopic analysis, including MS, NMR and UV techniques. Eight compounds of all isolated compounds showed inhibitory effects on the lipid accumulation induced by high concentrations of palmitic acid and glucose in HepG2 cells. Four selected compounds were tested for lipid content in a dose-dependent manner (10, 20 and 40 μM), and among those compounds, kaempferol 3-O-β- d -glucopyranosyl-7-O-α- l -rhamnopyranoside showed the strongest inhibition of hepatic lipid production in HepG2 cells. In an oil-red O staining assay, five compounds were shown to reduce hepatic lipid accumulation better than what was observed in the vehicle control group. The present study suggests a new class of chemical entities for developing bioactive agents for the treatment of diseases caused by fat accumulation in the liver.

This paper presents an adaptive fuzzy proportional integral sliding mode control (AFPISMC) for two-tank interacting system (TTIS). In order to maintain the desired liquid level of the TTIS and meet the reference values for attenuated chattering problems, this paper proposes a combination of a sliding mode control (SMC) with a proportional integral (PI) sliding surface and a fuzzy inference system. Fuzzy logic and the universal approximation theorem of fuzzy systems are used to approximate the uncertain function in the PISMC. The stability of the control system is proved by the Lyapunov theory. The simulation results of the proposed method in MATLAB/Simulink were compared to a fuzzy control, a sliding mode control with conditional integrals, a fuzzy-PID control, and a conventional PID control. The comparison results showed that the proposed controller was most effective when the rising time reached 0.2375 s, the percent of overshoot was 0%, the steady state error converged to zero, the settling time was 0.4612 s, and chattering was reduced.

As part of ongoing research to find new antidiabetic agents from medicinal plants, the chemical composition of Gynostemma longipes, an ethnomedicinal plant used to treat type 2 diabetes mellitus by local communities in Vietnam, was investigated. Ten new dammarane triterpenes, including two 3,4- seco-dammarane analogues, secolongipegenins S1 and S2 (1 and 2), a 3,4- seco-hexanordammarane, secolongipegenin S3 (3), two hexanordammarane glycosides, longipenosides ND1 and ND2 (4 and 5), and five other dammarane glycosides, longipenosides GL1-GL5 (6-10), were isolated from a 70% EtOH extract of the whole G. longipes plant. The structures of the new compounds were elucidated using diverse spectroscopic methods. All of the isolates were evaluated for their stimulatory activities on glucose uptake in differentiated 3T3-L1 adipocyte cells using 2-[ N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose as a fluorescent-tagged glucose probe. The stimulant activities on glucose uptake by the test compounds were mediated via the activation of the AMPK pathway using differentiated mouse C2C12 skeletal myoblasts. Consequently, compounds 1, 2, and 4 enhanced glucose uptake and GLUT4 translocation significantly by regulating the AMPK signaling pathway.

In this study, nanocrystalline ZnNdxFe2−xO4 ferrites with x = 0.0, 0.01, 0.03 and 0.05 were fabricated and used as a catalyst for dye removal potential. The effect of Nd3+ ions substitution on the structural, optical and photo-Fenton activity of ZnNdxFe2−xO4 has been investigated. The addition of Nd3+ ions caused a decrease in the grain size of ferrites, the reduction of the optical bandgap energies and thus could be well exploited for the catalytic study. The photocatalytic activity of the ferrite samples was evaluated by the degradation of Rhodamine B (RhB) in the presence of H2O2 under visible light radiation. The results indicated that the ZnNdxFe2−xO4 samples exhibited higher removal efficiencies than the pure ZnFe2O4 ferrites. The highest degradation efficiency was 98.00%, attained after 210 min using the ZnNd0.03Fe1.97O4 sample. The enhanced photocatalytic activity of the ZnFe2O4 doped with Nd3+ is explained due to the efficient separation mechanism of photoinduced electron and holes. The effect of various factors (H2O2 oxidant concentration and catalyst loading) on the degradation of RhB dye was clarified.

With the advent of senolytic agents capable of selectively removing senescent cells in old tissues, the perception of age-associated diseases has been changing from being an inevitable to a preventable phenomenon of human life. In the search for materials with senolytic activity from natural products, six new flavonostilbenes (

This research was conducted to evaluate the effect of $\alpha$-amylase and glucoamylase mixture at various hydrolysis time (0,4,6,8 and 12 hours) to morphological characteristics and physical properties of porous corn starch granules. Scanning Electron Microscopy (SEM) showed the number and size of holes on the surface of starch granules increased with hydrolysis time; moreover, starch granule structure was broken at 8 and 12 hours. The hydrolyzed level of starch granules was increased gradually with reaction time; the highest hydrolysis value was 63.534% in 12 hours of reaction. The results indicated that porous starch had higher adsorption capacity than native starch which was showed in higher oil and water holding ability. Additionally, swelling and solubility of porous corn starch were increased with the prolonging of hydrolysis time and higher than that of native starch samples. Color value tended to increase with increasing hydrolysis time; however, the difference was very small. The results also indicated that viscosity and transmittance of the hydrolyzed starch sample decreased as the hydrolysis time increased as well as lower than native starch. Thus, porous corn starch could be a potential ingredient in the food field.

Senescent cells drive atherosclerosis at all stages and contribute to cardiovascular disease. However, the markers in these senescent aortic plaques have not been well studied, creating a huge obstacle in the exploration of a precise and efficient system for atherosclerosis treatment. Recently, CD9 has been found to induce cellular senescence and aggravated atherosclerotic plaque formation in apolipoprotein E knockout (ApoE-/-) mice. In the present study, this result has been leveraged to develop CD9 antibody-modified, hyaluronic acid-coated mesoporous silica nanoparticles with a hyaluronidase-responsive drug release profile. In invitro models of senescent foamy macrophages and senescent endothelial cells stimulated with oxidized high-density-lipoprotein, the CD9 antibody-modified mesoporous silica nanoparticles exhibit high cellular uptake; reduce the reactive oxygen species level, high-density lipoprotein oxidation, and production of TNF-α and IL-6; and attenuate the senescence process, contributing to improved cell viability. In vivo experiment demonstrated that these nanoparticles can successfully target the senescent lesion areas, deliver the anti-senescence drug rosuvastatin to the senescent atherosclerotic plaques (mainly endothelial cells and macrophages), and alleviate the progression of atherosclerosis in ApoE-/- mice. By providing deep insight regarding the markers in senescent atherosclerotic plaque and developing a nano-system targeting this lesion area, the study proposes a novel and an accurate therapeutic approach for mitigating atherosclerosis through senescent cell clearance.

Ethnopharmacological relevance G. pentaphyllum, also known as Jiao-Gu-Lan, has been used traditionally as folk remedies for many diseases, including diabetes mellitus, metabolic syndrome, aging, and neurodegenerative diseases in China and some countries in East and Southeast Asia. It is considered as an “immortality herb” in Guizhou Province, because it was consumed regularly by the elderly native inhabitants. Other species of the same genus Gynostemma such as G. longipes and G. laxum have been used as alternatives to G. pentaphyllum in ethno-medicine in Vietnam and other Asian countries. Aim of the review The review aims to summarize up-to-date study results on Gynostemma species, including traditional usage, phytochemical profile, pharmacological activities, and toxicological studies, in order to suggest future research orientation and therapeutic applications on acute and chronic diseases. Materials and methods The relevant literature on the genus Gynostemma was gathered from secondary databases (Web of Science and PubMed), books, and official websites. The latest literature cited in this review was published in February 2020. Results The genus Gynostemma has been widely used in traditional medicine, mainly for treatment of diabetes, hypertension, obesity, and hepatosteatosis. To date, 328 dammarane-type saponins were isolated and structurally elucidated from Gynostemma species. Crude extracts, saponin-rich fractions (gypenosides), and pure compounds were reported to show a wide range of pharmacological activities in both in vitro and in vivo experiments. The most notable pharmacological effects were anti-cancer, cardioprotective, hepatoprotective, neuroprotective, anti-diabetic, anti-obesity, and anti-inflammatory activities. Toxicological studies were conducted only on G. pentaphyllum, showing that the plant extracts were relatively safe in both acute and long-term toxicity experiments at the given dosage while no toxicological studies were reported for the other species. Conclusions The review summarizes current studies on traditional uses, phytochemistry, biological properties, and toxicology of medicinal Gynostemma species. Till now, the majority of publications still focused only on G. pentaphyllum. However, the promising preliminary data of other Gynostemma species indicated the research potential of this genus, both in phytochemical and pharmacological aspects. Furthermore, clinical data are required to evaluate the efficacy and undesired effects of crude extracts, standard saponin fractions, and pure compounds prepared from Gynostemma medicinal plants.