Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 105
Filtrar
1.
Angew Chem Int Ed Engl ; : e202411265, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39183714

RESUMO

The [2+2] cycloaddition reaction between the Si=C double bond of adamantylsilene and the carbonyl group of aliphatic, aromatic or acetylenic ketones and aldehydes is demonstrated. The product of this reaction that is central to a non-ionic version of the Peterson olefination is an unusual four-membered 1,2-silaoxetane heterocycle that was characterized spectroscopically and crystallographically. In the presence of SiO2, the silaoxetane undergoes retro-cycloaddition with the formation of alkene products. As the [2+2] cycloaddition proceeds without the necessity of any base, enolizable ketones can be converted into olefins. In addition, it is shown that the adamantylsilene can be produced in situ by a sila-Peterson reaction, providing valuable input for the development of a new one-pot silicon-based reductive carbonyl-carbonyl cross coupling methodology.

2.
J Extracell Vesicles ; 13(7): e12457, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39007430

RESUMO

Seminal plasma induces immune tolerance towards paternal allogenic antigens within the female reproductive tract and during foetal development. Recent evidence suggests a role for extracellular vesicles in seminal plasma (spEVs). We isolated spEVs from seminal plasma that was donated by vasectomized men, thereby excluding any contributions from the testis or epididymis. Previous analysis demonstrated that such isolated spEVs originate mainly from the prostate. Here we observed that when isolated fluorescently labelled spEVs were mixed with peripheral blood mononuclear cells, they were endocytosed predominantly by monocytes, and to a lesser extent also by T-cells. In a mixed lymphocyte reaction, T-cell proliferation was inhibited by spEVs. A direct effect of spEVs on T-cells was demonstrated when isolated T cells were activated by anti-CD3/CD28 coated beads. Again, spEVs interfered with T cell proliferation, as well as with the expression of CD25 and the release of IFN-γ, TNF, and IL-2. Moreover, spEVs stimulated the expression of Foxp3 and IL-10 by CD4+CD25+CD127- T cells, indicating differentiation into regulatory T-cells (Tregs). Prior treatment of spEVs with proteinase K revoked their effects on T-cells, indicating a requirement for surface-exposed spEV proteins. The adenosine A2A receptor-specific antagonist CPI-444 also reduced effects of spEVs on T-cells, consistent with the notion that the development of Tregs and their immune suppressive functions are under the influence of adenosine-A2A receptor signalling. We found that adenosine is highly enriched in spEVs and propose that spEVs are targeted to and endocytosed by T-cells, after which they may release their adenosine content into the lumen of endosomes, thus allowing endosome-localized A2A receptor signalling in spEVs targeted T-cells. Collectively, these data support the idea that spEVs can prime T cells directly for differentiation into Tregs.


Assuntos
Diferenciação Celular , Vesículas Extracelulares , Sêmen , Linfócitos T Reguladores , Humanos , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Sêmen/metabolismo , Sêmen/imunologia , Masculino , Proliferação de Células , Ativação Linfocitária/imunologia
3.
Heliyon ; 10(11): e32703, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38912482

RESUMO

Cocoa pod husk (CPH) is a major residue of cocoa processing industry, while medicinal plant H. hirsuta is used for treatment of malaria and diabetes mellitus in folk medicine. This study aimed to produce microencapsulated powders from saponin-enriched CPH and H. hirsuta extracts and assess their physicochemical, phytochemical, antioxidant, and α-glucosidase inhibition properties. The findings show that the microencapsulated powders were achieved diserable physicochemical properties (moisture of 3.22-4.76 %, water activity of 0.43-0.46, water solubility index of 74.18-88.77 %, particle size of 254.2-719.7 nm, and zeta potential from -6.97 to -15.1 mV). The phytochemical content of microencapsulated CPH powders gained at high levels (total saponin content of 151.87-193.46 mg EE/g DS, total flavonoid content of 33.80-46.05 mg CE/g DS), total alkaloid content of 15.20-24.23 mg AA/g DS, and total phenolic content of 5.41-6.49 mg GAE/g DS). The antioxidant potential of microencapsulated CPH powders using ARSC and FRAP assays was 15.51-18.20 and 9.61-11.89 mg TE/g DS, respectively, while their α-glucosidase inhibition capacity at 100 µg/mL was found at 51.74-52.16 %. The phytochemical content (except total alkaloid content), antioxidant, and α-glucosidase inhibitory potential of microencapsulated CPH powders were smaller than those of microencapsulated H. hirsuta and combined powders. This study reveals that the microencapsulated CPH and H. hirsuta powders were prospective in reducing hyperglycemia activity. Therefore, this study provided an evidence for further application of CPH and H. hirsuta plant for functional food development.

4.
PLoS One ; 19(6): e0305869, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38913676

RESUMO

BACKGROUND: This study aimed to measure the preferences for mental health support among health professionals, their willingness to support the mental health of colleagues and associated factors. METHOD: A descriptive cross-sectional study was performed from August to October 2022 within five hospitals located in Hanoi, Vietnam. A total of 244 health professionals participated in the study. Data on socio-economic status, health and COVID-19-related characteristics, Depression Anxiety Stress Scale (DASS-21); and preferences for mental health support services were collected by using a structured self-reported questionnaire. Multivariate logistic regression models were utilized to identify associated factors with the demand for mental support services. RESULTS: 13.9%, 17.1% and 8.6% reported having at least mild depression, anxiety and stress, respectively. There 13.9% did not seek any mental health support during the COVID-19 pandemic. The most common support included talking with friends (52.9%), family (50.8%), colleagues (47.6%) and using social networks/Internet (43.5%). There 31.1% had been aware of mental health services, but only 18.0% used this service at least once. Regarding preferences, 47.3% had a demand for mental support services, and the most preferred service was providing coping skills (25.9%), followed by skills to support others against mental problems (22.2%). Major sources of support included psychiatrists (34.4%), colleagues (29.1%) and family (27.9%). The main preferred channels for support included telephone/mobile phone (35.7%) and Internet (20.9%). Only 12.3% were willing to provide mental support for colleagues during the pandemic. Age, education, perceived mental health status, ever seeking any mental service, and DASS-21 depression score were associated with demand for mental support services. CONCLUSION: This study found a lack of awareness of mental health services for health professionals, as well as moderate levels of demand for this service in this population. Raising awareness and developing tailored mental health support services are important to enhancing the mental well-being of health professionals in Vietnam to prepare for the next pandemic.


Assuntos
COVID-19 , Depressão , Pessoal de Saúde , Serviços de Saúde Mental , Saúde Mental , Humanos , COVID-19/epidemiologia , COVID-19/psicologia , Vietnã/epidemiologia , Masculino , Feminino , Adulto , Estudos Transversais , Pessoal de Saúde/psicologia , Pessoa de Meia-Idade , Depressão/epidemiologia , Ansiedade/epidemiologia , Pandemias , Inquéritos e Questionários , SARS-CoV-2 , Estresse Psicológico/epidemiologia , Apoio Social
5.
Curr Dev Nutr ; 8(6): 102063, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38817706

RESUMO

Background: Adolescent nutrition has faced a policy neglect, partly owing to the gaps in dietary intake data for this age group. The Food Recognition Assistance and Nudging Insights (FRANI) is a smartphone application validated for dietary assessment and to influence users toward healthy food choices. Objectives: This study aimed to assess the feasibility (adherence, acceptability, and usability) of FRANI and its effects on food choices and diet quality in female adolescents in Vietnam. Methods: Adolescents (N = 36) were randomly selected from a public school and allocated into 2 groups. The control group received smartphones with a version of FRANI limited to dietary assessment, whereas the intervention received smartphones with gamified FRANI. After the first 4 wk, both groups used gamified FRANI for further 2 wk. The primary outcome was the feasibility of using FRANI as measured by adherence (the proportion of completed food records), acceptability and usability (the proportion of participants who considered FRANI acceptable and usable according to answers of a Likert questionnaire). Secondary outcomes included the percentage of meals recorded, the Minimum Dietary Diversity for Women (MDDW) and the Eat-Lancet Diet Score (ELDS). Dietary diversity is important for dietary quality, and sustainable healthy diets are important to reduce carbon emissions. Poisson regression models were used to estimate the effect of gamified FRANI on the MDDW and ELDS. Results: Adherence to the application was 82% and the percentage of meals recorded was 97%. Acceptability and usability were 97%. MDDW in the intervention group was 1.07 points (95% CI: 0.98, 1.18; P = 0.13) greater than that in the control (constant = 4.68); however, the difference was not statistically significant. Moreover, ELDS in the intervention was 1.09 (95% CI: 1.01, 1.18; P = 0.03) points greater than in the control (constant = 3.67). Conclusions: FRANI was feasible and may be effective to influence users toward healthy food choices. Research is needed for FRANI in different contexts and at scale.The trial was registered at the International Standard Randomized Controlled Trial Number as ISRCTN 10681553.

6.
Nanoscale Adv ; 6(5): 1460-1466, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38419870

RESUMO

These days, photodetectors are a crucial part of optoelectronic devices, ranging from environmental monitoring to international communication systems. Therefore, fabricating these devices at a low cost but obtaining high sensitivity in a wide range of wavelengths is of great interest. This report introduces a simple solution-processed hybrid 2D structure of CuO and rGO for broadband photodetector applications. Particularly, 2D CuO acts as the active material, absorbing light to generate electron-hole pairs, while 2D rGO plays the role of a transport layer, driving charge carriers between two electrodes. Our device exhibits remarkable sensitivity to a wide wavelength range from 395 nm to 945 nm (vis-NIR region). Interestingly, our devices' responsivity and photoconductive gain were calculated (under 395 nm wavelength excitation) to be up to 8 mA W-1 and 28 fold, respectively, which are comparable values with previous publications. Our hybrid 2D structure between rGO and CuO enables a potential approach for developing low-cost but high-performance optoelectronic devices, especially photodetectors, in the future.

7.
Nat Prod Res ; : 1-6, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38353156

RESUMO

A new compound, conamonin A (1), was isolated from the whole plants of Conamomum rubidum with eight known dihydrochalcones (2-9). Their structures were elucidated by a combination of spectroscopic methods as well as by comparison with previously reported data. The absolute configuration of 1 was assigned by TDDFT-ECD method. Compounds 1 and 8 showed inhibitory activity against LPS-induced NO production in the RAW 264.7 cells, with IC50 values of 58.29 ± 2.88 and 81.77 ± 5.99 µM, respectively. Compounds 3/4 and 5/6 exhibited inhibitory effects, with IC50 values of 28.76 ± 1.16 and 29.89 ± 1.79 µg/mL, respectively. Compounds 2, 7-9 exhibited significant cytotoxic activity against human lung carcinoma (the SK-LU-1 cell line) with IC50 values ranging from 9.87 to 17.99 µM. This study offers valuable insights into the chemical constituents and biological activities of Conamomum rubidum, highlighting its potential as a source for discovering new anti-inflammatory and cytotoxic agents.

8.
R Soc Open Sci ; 11(1): 231343, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38298403

RESUMO

Today, nanoscrystals are researched and developed very quickly because of their advantages in many areas of life. One of the potential applications is quantum dot-sensitized solar cells. This is a green, clean, environmentally friendly cell, and has been studied by scientists since 2000. In this study, we fabricated photoanodes with Cu2+ ions co-doped into cadmium sulfide (CdS) and cadmium selenide (CdSe) nanoscrystals by successive ionic layer adsorption and reaction, and chemical bath deposition methods to improve absorption spectral intensity of films. The results showed that the absorption intensity increased by eight times compared with our previous results on Cu2+ ions doped with CdSe nanoscrystals. The CdS:Cu2+ film is optimized at 2% doping, the efficiency is 4.6819%, and the current density is 27.3501 mA.cm-2, which is higher when compared with the Cu2+ ion only doped into the CdSe quantum dot (19.915 mA.cm-2). In addition, the composition of the photoanode was determined by surface and cross-sectional field-emission scanning electron microscope images, and the structure of the film was determined by X-ray diffraction, energy-dispersive X-ray spectroscopy mapping and X-ray photoelectron spectroscopy. Finally, the film's optical properties were studied by ultraviolet-visible spectroscopy, photoluminescence spectroscopy and electrochemical properties by electrochemical impedance spectroscopy. The results obtained have been discussed and presented in great detail.

9.
Bioorg Med Chem Lett ; 98: 129574, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38052378

RESUMO

Aurones are a minor subgroup of flavonoids. Unlike other subgroups such as chalcones, flavones, and isoflavones, aurones have not been extensively explored as pancreatic lipase inhibitors. In this work, we studied the pancreatic lipase inhibitory potency of synthetic aurone derivatives. Thirty-six compounds belonging to four series (4,6-dihydroxyaurone, 6-hydroxyaurone, 4,6-dialkoxyaurone, and 6-alkoxyaurone) were designed and synthesized. Their in vitro inhibitory activities were determined by spectrophotometric assay in comparison with quercetin and orlistat. Alkoxyaurone derivatives with long-chain (6-10 carbons) alkoxy substituents showed greater potency. Of them, 4,6-dialkoxyaurone 8 displayed the highest activity against pancreatic lipase (IC50 of 1.945 ± 0.520 µM) relative to quercetin (IC50 of 86.98 ± 3.859 µM) and orlistat (IC50 of 0.0334 ± 0.0015 µM). Fluorescence quenching measurement confirmed the affinity of alkoxyaurone derivatives to pancreatic lipase. Kinetic study showed that 8 inhibited lipase through a competitive mechanism (Ki of 1.288 ± 0.282 µM). Molecular docking results clarified the role of long-chain substituents on ring A in interacting with the hydrophobic pockets and pushing the inhibitor molecule closer to the catalytic triad. The findings in this study may contribute to the development of better pancreatic lipase inhibitors with aurone structure.


Assuntos
Lipase , Quercetina , Inibidores Enzimáticos/química , Flavonoides/química , Lipase/antagonistas & inibidores , Simulação de Acoplamento Molecular , Orlistate/farmacologia
10.
Future Virol ; 18(8): 501-516, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38051989

RESUMO

Aim: To generate mRNAs encoding conserved regions within SARS-CoV-2 ORF1ab which can induce strong T-cell responses to overcome the immune invasion of newly emergent variants. Methods: We selected two conserved regions with a high density of T-cell epitopes using immunoinformatics for mRNA synthesis. The ability of testing mRNAs to activate T cells for IFN-γ production was examined by an ELISpot assay and flow cytometry. Results: Two synthesized mRNAs were successfully translated in MDA-MB-231 cells and had comparable potency to the spike mRNA to induce CD4+ and CD8+ T-cell responses in peripheral blood mononuclear cells in 29 out of 34 participants. Conclusion: This study provides a proof-of-concept for the use of SARS-CoV-2 conserved regions to develop booster vaccines capable of eliciting T-cell-mediated immunity.

11.
Lancet Reg Health West Pac ; 40: 100943, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38116497

RESUMO

This study aims to investigate climate change's impact on health and adaptation in Vietnam through a systematic review and additional analyses of heat exposure, heat vulnerability, awareness and engagement, and projected health costs. Out of 127 reviewed studies, findings indicated the wider spread of infectious diseases, and increased mortality and hospitalisation risks associated with extreme heat, droughts, and floods. However, there are few studies addressing health cost, awareness, engagement, adaptation, and policy. Additional analyses showed rising heatwave exposure across Vietnam and global above-average vulnerability to heat. By 2050, climate change is projected to cost up to USD1-3B in healthcare costs, USD3-20B in premature deaths, and USD6-23B in work loss. Despite increased media focus on climate and health, a gap between public and government publications highlighted the need for more governmental engagement. Vietnam's climate policies have faced implementation challenges, including top-down approaches, lack of cooperation, low adaptive capacity, and limited resources.

12.
Nat Prod Res ; : 1-7, 2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-37950747

RESUMO

Owing to the challenges of antimicrobial resistance, investigations of new antibiotics from medicinal plants are continuously being conducted. Peperomia pellucida is a pantropical plant used in traditional medicine for the treatment of various disorders. From the ethanol extract of a whole P. pellucida plant, one previously undescribed carotane sesquiterpene (pellucarotine), one known carotane sesquiterpene (daucol), and one phenylpropanoid (dillapiol) were isolated and structurally elucidated. Their structures were determined based on 1D and 2D NMR, HR-ESI-Mass, experimental, and computational electronic circular dichroism spectroscopic data and compared with those reported in the literature. Antimicrobial assay results showed that pellucarotine had an anti-infective effect on Candida albicans with an MIC of 512 µg/mL.

13.
Pak J Biol Sci ; 26(7): 371-379, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37902078

RESUMO

<b>Background and Objective:</b> Isolation and investigation of plant growth promoting bacteria on potato plants can provide significant information for the application of beneficial bacteria in potato production. This study aims to isolate and characterize endophytic bacteria isolated from potato roots. In addition, the potential application of endophytes in promoting potato growth under <i>in vitro</i> conditions was also investigated. <b>Materials and Methods:</b> The roots from 15 healthy potato plants were excised and surface sterilized by NaOCl and finally rinsed by sterilized water. The confirmed surface-sterilized roots were then aseptically cut into small fragments and spread onto the isolation media, followed by incubation at 27°C for up to 3 days. Six isolates that showed differences in colony morphology were selected for further investigation. All isolates were screened for IAA production, nitrogen fixation, and phosphate solubilization. <b>Results:</b> Five of the isolates were identified as <i>Bacillus</i> and isolate 30 was identified as <i>Paenibacillus alvei</i>. All isolates exhibited good IAA production. While Iso-27 had no nitrogen fixation activity, Iso-28 showed the highest level of nitrogen fixation activity (3.59 mg L<sup>1</sup>), four isolates (Iso-9, Iso-10, Iso-11, Iso-28) could solubilize phosphate, ranging from 49.64 g L<sup>1</sup> to 67.98 mg L<sup>1</sup>. After being inoculated with <i>in vitro</i> potato plants, isolates 9, 10, 28, 30, improved the stalk length, root number, fresh mass and dried mass of the potato plants. <b>Conclusion:</b> The four isolates can potentially be applied in <i>in vitro</i> potato culture.


Assuntos
Bacillus , Solanum tuberosum , Ácidos Indolacéticos , Desenvolvimento Vegetal , Fosfatos
14.
Vasc Health Risk Manag ; 19: 663-672, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37872943

RESUMO

Objective: Study on effect of risk factors on over-anticoagulation in patients taking anticoagulant drugs with VKAs (vitamin K antagonists). Methods: Cross-sectional descriptive, prospective research. Study on 79 patients taking anticoagulant drugs with VKAs who had an INR (International Normalized Ratio) index of more than indicated anticoagulation dose with VKAs therapy. Results: A total of 79 patients, mean age 65.65 ± 12.17 years [33:85], the elderly group is common (73.4%). Patients had hemorrhage disorders account for 22.8%. The INR index had an average value was 5.88 ± 3.0 [3.02-23.95]; The INR> 5 level group is a higher risk of bleeding than the INR ≤5 level group, it's the statistical significance (p < 0.001). The risk factors such as drugs to treat dyslipidemia, hyperthyroid, amiodarone, beta blocker, prednisone, NSAIDs (Non-steroidal anti-inflammatory), BMI (Body Mass Index), smoke and alcohol that the risk factors of increasing of bleeding when receiving anticoagulants but it's not statistically significant yet (OR >1, p > 0.05); These patients using coenzyme Q10 and green vegetable nutrition such as cruciferous vegetables (Brassicaceae, Asteraceae) are quite common (31.6% and 35.4%), its effect on coagulation with vitamin K and cause of the increased in risk of bleeding was statistical significantly with OR = 5.28 (CI: 1.72-16.17, p < 0.01), and OR = 2.99 (CI: 1.01-8.80, p < 0.05) respectively. Conclusion: Most patients in over-anticoagulation were the elderly group. Patients had hemorrhage disorders account for 22.8%. The INR> 5 level group was a higher risk of bleeding than the INR ≤5 level group with statistical significance. Patients using Coenzyme Q10 and green vegetable nutrition such as cruciferous vegetables (Brassicaceae, Asteraceae) are quite common, its effect on coagulation and cause of the increased risk of bleeding complication with statistical significance.


Assuntos
Anticoagulantes , Hemorragia , Humanos , Idoso , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Transversais , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia , Coeficiente Internacional Normatizado , Fatores de Risco , Vitamina K/uso terapêutico , Fibrinolíticos/uso terapêutico
15.
J Phys Chem Lett ; 14(32): 7264-7273, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37555944

RESUMO

The rational design of highly active and stable electrocatalysts toward the hydrogen evolution reaction (HER) is highly desirable but challenging in seawater electrolysis. Herein we propose a strategy of boron-doped three-dimensional Ni2P-MoO2 heterostructure microrod arrays that exhibit excellent catalytic activity for hydrogen evolution in both alkaline freshwater and seawater electrolytes. The incorporation of boron into Ni2P-MoO2 heterostructure microrod arrays could modulate the electronic properties, thereby accelerating the HER. Consequently, the B-Ni2P-MoO2 heterostructure microrod array electrocatalyst exhibits a superior catalyst activity for HER with low overpotentials of 155, 155, and 157 mV at a current density of 500 mA cm-2 in 1 M KOH, 1 M KOH + NaCl, and 1 M KOH + seawater, respectively. It also exhibits exceptional performance for HER in natural seawater with a low overpotential of 248 mV at 10 mA cm-2 and a long-lasting lifetime of over 100 h.

16.
Heliyon ; 9(8): e19148, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37636421

RESUMO

Introduction: Piper lolot is a species of herb used as a popular food in Vietnam. Furthermore, the species has been used as a Vietnamese traditional medicine to treat many diseases. Methods: Chemical constituents in the essential oil from leaves of Piper lolot were determined using GC/MS analysis. The anti-gout and anti-diabetic activities of the essential oil were determined through the inhibitory assays against xanthine oxidase, α-glucosidase and α-amylase enzymes. In addition, molecular docking simulations were used to elucidate the inhibitory mechanism between the main compounds and the enzymes. Results: The dominant constituents of the Piper lolot essential oils were determined as ß-caryophyllene (20.6%), ß-bisabolene (11.6%), ß-selinene (8.4%), ß-elemene (7.7%), trans-muurola-4(14),5-diene (7.4%), and (E)-ß-ocimene (6.7%). The essential oil displayed xanthine oxidase, α-amylase, and α-glucosidase inhibitory activities with IC50 values of 28.4, 130.6, and 59.1 µg/mL, respectively. The anti-gout and anti-diabetic activities of the essential oil from the P. lolot species are reported for the first time. Furthermore, molecular docking simulation was consistent to in vitro experiments. Conclusion: The present study provides initial evidence that the essential oil of P. lolot may be a potential natural source to develop new diabetes preparations.

17.
RSC Adv ; 13(30): 20565-20574, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37435373

RESUMO

In the present study, Lam Dong bentonite clay was utilized as a novel resource to effectively synthesize microporous ZSM-5 zeolite (Si/Al ∼ 40). The effects of aging and hydrothermal treatment on the crystallization of ZSM-5 were carefully investigated. Herein, the aging temperatures of RT, 60, and 80 °C at time intervals of 12, 36, and 60 h, followed by high temperature hydrothermal treatment (170 °C) for 3-18 h were studied. Techniques such as XRD, SEM-EDX, FTIR, TGA-DSC, and BET-BJH were applied to characterize the synthesized ZSM-5. Bentonite clay showed great benefits as a natural resource for ZSM-5 synthesis and is cost efficient, environment friendly, and has a large reserves. The form, size, and crystallinity of ZSM-5 were greatly influenced by aging and hydrothermal treatment conditions. The optimal ZSM-5 product had high purity, crystallinity (∼90%), and porosity (BET ∼380 m2 g-1) as well as thermal stability, which are beneficial for adsorptive and catalytic applications.

18.
RSC Adv ; 13(26): 17587-17594, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37312988

RESUMO

Two styryl-lactone derivatives (1 and 2) were isolated from the aerial parts of Goniothalamus elegans. Compound 1 is a newly discovered natural product, and compound 2 is reported in this plant for the first time. The absolute configuration of 1 was determined based on the ECD spectrum. The two styryl-lactone derivatives were tested for cytotoxicity activity against five cancer cell lines and human embryonic kidney cells. The newly discovered compound demonstrated potent cytotoxicity, with IC50 values ranging from 2.05 to 3.96 µM. Computational methods were also applied to investigate the mechanism of the cytotoxic activity of the two compounds. Density functional theory and molecular mechanisms were used to assess the interaction between protein targets to compound 1 and 2, respectively, through the EGF/EGFR signaling pathway. The results indicated that 1 showed a strong binding affinity for two proteins EGFR and HER-2. Finally, ADMET predictions were used to validate the pharmacokinetics and toxicity of these compounds. The results showed that both compounds are likely to be absorbed in the gastrointestinal tract and penetrate the blood-brain barrier. Based on our findings, these compounds may have potential for further studies to be developed into active ingredients for cancer treatment.

19.
Des Monomers Polym ; 26(1): 171-181, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37313390

RESUMO

In this work, polypyrrole-based nanocomposites doped with graphene oxide, molybdate, and salicylate (PPy/GO/Mo/Sal) were synthesized via in situ electrochemical polymerization to enhance the anti-corrosion protection performance of polymer coatings. The morphology and structures of the coatings were characterized by SEM, EDX, FTIR, Raman spectroscopy, and XRD. The protection abilities of coatings against corrosion were investigated in 0.1 M NaCl solution with EIS potentiodynamic polarization, salt spray test, and open-circuit potential (OCP) measurements. The results showed that with the presence of both molybdate/salicylate and GO in the PPy matrix, the nanocomposite coating exhibited an excellent protection ability against corrosion for low-carbon steel, better than that with only GO as filler. Compared to the nanocomposites doped with only salicylate or salicylate/GO, the one doped with both molybdate/salicylate and GO exhibited the longest protection plateau (ca. 100 h) on the OCP-time curves with some fluctuation points known as the self-healing action of molybdate dopant. It also resulted in a decrease in the corrosion current (Tafel plots), a higher impedance (Bode plot), and a better protection performance in salt spray tests. In this case, the anti-corrosion ability of the coatings was provided through a barrier and self-healing mechanism.

20.
Mycobiology ; 50(5): 389-398, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36404896

RESUMO

Endophytic fungi are promising sources for the production of podophyllotoxin-an important anticancer compound, replacing depleted medical plants. In this study, the endophytes associated with Dysosma difformis-an ethnomedicinal plant species were isolated to explore novel sources of podophyllotoxin. Fifty-three endophytic fungi were isolated and identified by morphological observation and ITS-based rDNA sequencing, assigning them to 27 genera in 3 divisions. Fusarium was found the most prevalent genus with a colonization frequency of 11.11%, followed by Trametes (9.26%) and Penicillium (7.41%). Phylogenetic trees were constructed for the endophytic fungi community in two collection sites, Ha Giang and Lai Chau, revealing the adaptation of the species to the specific tissues and habitats. Cytotoxic activity of endophytic fungal extracts was investigated on cancer cell lines such as SK-LU-1, HL-60, and HepG2, demonstrating strong anti-cancer activity of six isolates belonging to Penicillium, Trametes, Purpureocillium, Aspergillus, and Ganoderma with IC50 value of lower than 10 µg/mL. The presence of podophyllotoxin was indicated in Penicillium, Trametes, Aspergillus and for the first time in Purpureocillium and Ganoderma via high-performance liquid chromatography, which implied them as a potential source of this anti-cancer compound.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA