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1.
Nutrients ; 16(17)2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39275157

RESUMEN

As part of our ongoing research on new anti-diabetic compounds from ethnopharmacologically consumed plants, two previously undescribed lupane-type triterpenoids (1 and 2) with dicarboxylic groups, an undescribed nor-taraxastane-type triterpenoid (3), and 14 known compounds (4-17) were isolated from the leaves of Cleistocalyx operculatus. Extensive spectroscopic analysis (IR, HRESIMS, 1D, and 2D NMR) was used for structure elucidation, while the known compounds were compared to reference data reported in the scientific literature. All the isolates (1-17) were evaluated for their inhibitory effects on the protein tyrosine phosphatase 1B (PTP1B) enzyme. Compounds 6, 9, and 17 showed strong PTP1B inhibitory activities. The mechanism of PTP1B inhibition was studied through enzyme kinetic experiments. A non-competitive mechanism of inhibition was determined using Lineweaver-Burk plots for compounds 6, 9, and 17. Additionally, Dixon plots were employed to determine the inhibition constant. Further insights were gained through a structure-activity relationship study and molecular docking analysis of isolated compounds with the PTP1B crystal structure. Moreover, all isolates (1-17) were tested for their stimulatory effects on the uptake of 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl) amino]-D-glucose (2-NBDG) in differentiated 3T3-L1 adipocyte cells. Compounds 6, 13, and 17 exhibited strong glucose absorption stimulation activity in a dose-dependent manner.


Asunto(s)
Células 3T3-L1 , Glucosa , Simulación del Acoplamiento Molecular , Hojas de la Planta , Proteína Tirosina Fosfatasa no Receptora Tipo 1 , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo , Hojas de la Planta/química , Ratones , Animales , Glucosa/metabolismo , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/aislamiento & purificación , Extractos Vegetales/farmacología , Extractos Vegetales/química , Syzygium/química , Hipoglucemiantes/farmacología , Hipoglucemiantes/química , Relación Estructura-Actividad , Simulación por Computador
2.
Future Sci OA ; 10(1): 2395244, 2024 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-39254097

RESUMEN

The emergence of multicancer early detection (MCED) tests holds promise for improving early cancer detection and public health outcomes. However, positive MCED test results require confirmation through recommended cancer diagnostic imaging modalities. To address these challenges, we have developed a consultation and work-up protocol for definitive diagnostic results post MCED testing, named SPOT-MAS. Developed through circulating tumor DNA (ctDNA) analysis and in line with professional guidelines and advisory board consensus, this protocol standardizes information to aid general practitioners in accessing, interpreting and managing SPOT-MAS results. Clinical effectiveness is demonstrated through a series of identified cancer cases. Our research indicates that the protocol could empower healthcare professionals to confidently interpret circulating tumor DNA test results for 5 common types of cancer, thereby facilitating the clinical integration of MCED tests.


New tests can now screen for multiple types of cancer early, offering hope for better health outcomes. If one of these tests shows a positive result, doctors need to confirm it with imaging tests. We have developed a guide to help doctors understand and confirm these results. This guide could help healthcare professionals interpret results for five common types of cancer, making it easier to use these tests in regular medical practice.

3.
Chem Biodivers ; : e202401934, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39187695

RESUMEN

From the leaves of Tithonia diversifolia,  nine sesquiterpenoids (1-9), including two new ones (1, 2) were isolated and structurally determined. Their chemical structures were elucidated by extensive analyses of HRESIMS and NMR spectral data, as well as comparison with the literature. All of the isolated compounds (except compounds 7, 8, 9) significantly exhibited cytotoxic activity against four human cancer cell lines (KB, HepG2, A549 and MCF7), with IC50 values ranging from 0.29-17.0 µM,  which was in the same range as the positive control ellipticine or even lower. Further, the apoptosis induction of two new compounds 1 and 2 were also investigated and reported. While compound 2 did not induce cell apoptosis in KB cells at test concentrations, compound 1 was found to possess anti-proliferative activity through concentration-dependently inducing cell cycle arrest at S phase, morphological changes, activation of caspase 3, and an increase in the early-stage apoptosis of KB cells at a concentration of 7.26 µM.

4.
Int J Equity Health ; 23(1): 163, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39152438

RESUMEN

BACKGROUND: Approximately 15% of women in low-and middle-income countries experience common perinatal mental disorders. Yet, many women, even if diagnosed with mental health conditions, are untreated due to poor quality care, limited accessibility, limited knowledge, and stigma. This paper describes how mental health-related stigma influences pregnant women's decisions not to disclose their conditions and to seek treatment in Vietnam, all of which exacerbate inequitable access to maternal mental healthcare. METHODS: A mixed-method realist study was conducted, comprising 22 in-depth interviews, four focus group discussions (total participants n = 44), and a self-administered questionnaire completed by 639 pregnant women. A parallel convergent model for mixed methods analysis was employed. Data were analyzed using the realist logic of analysis, an iterative process aimed at refining identified theories. Survey data underwent analysis using SPSS 22 and descriptive analysis. Qualitative data were analyzed using configurations of context, mechanisms, and outcomes to elucidate causal links and provide explanations for complexity. RESULTS: Nearly half of pregnant women (43.5%) would try to hide their mental health issues and 38.3% avoid having help from a mental health professional, highlighting the substantial extent of stigma affecting health-seeking and accessing care. Four key areas highlight the role of stigma in maternal mental health: fear and stigmatizing language contribute to the concealment of mental illness, rendering it unnoticed; unconsciousness, normalization, and low literacy of maternal mental health; shame, household structure and gender roles during pregnancy; and the interplay of regulations, referral pathways, and access to mental health support services further compounds the challenges. CONCLUSION: Addressing mental health-related stigma could influence the decision of disclosure and health-seeking behaviors, which could in turn improve responsiveness of the local health system to the needs of pregnant women with mental health needs, by offering prompt attention, a wide range of choices, and improved communication. Potential interventions to decrease stigma and improve access to mental healthcare for pregnant women in Vietnam should target structural and organizational levels and may include improvements in screening and referrals for perinatal mental care screening, thus preventing complications.


Asunto(s)
Trastornos Mentales , Aceptación de la Atención de Salud , Mujeres Embarazadas , Estigma Social , Humanos , Femenino , Vietnam , Embarazo , Adulto , Mujeres Embarazadas/psicología , Aceptación de la Atención de Salud/psicología , Trastornos Mentales/psicología , Trastornos Mentales/terapia , Encuestas y Cuestionarios , Grupos Focales , Adulto Joven , Accesibilidad a los Servicios de Salud , Investigación Cualitativa , Salud Mental , Adolescente
5.
Artículo en Inglés | MEDLINE | ID: mdl-39152047

RESUMEN

One new compound, methyl 3-((1-((2-carbamoylphenyl)amino)-1-oxopropan-2-yl)amino)-3-oxopropanoate (1), along with nine known secondary metabolites (2-10) were isolated and elucidated chemical structures from the methanol extract of the marine-derived fungus Penicillium chrysogenum VH17. Subsequent bioassays showed the antimicrobial and cytotoxic potential of the isolated compounds. All compounds 1-10 displayed antimicrobial effects against at least one tested reference microorganism with MIC values ranging from 32 to 256 µg mL-1. Furthermore, compound 4 exhibited significant cytotoxicity against all tested cell lines HepG2, A549, and MCF7 with IC50 values of 29.43 ± 1.37, 33.02 ± 1.53, and 36.72 ± 1.88 µM, respectively, whereas compound 3 exhibited weak cytotoxicity against MCF7 and HepG2 cell lines with IC50 values of 87.17 ± 6.31 and 97.32 ± 5.66 µM, respectively.

6.
J Nat Prod ; 87(8): 1903-1913, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39046805

RESUMEN

Four new compounds, racemic chalcone-monoterpene hybrids (1-3) and a chalcone (9), along with nine known compounds (4-8, 10-13), have been isolated from the buds of Cleistocalyx operculatus. The chemical structures of the isolated compounds were identified through NMR data analysis and confirmed by computational methods, including electronic circular dichroism (ECD) calculations, and further synthetic approaches. Compounds 1-5 were synthesized via a Diels-Alder reaction, a process informed by biomimetic condensation studies that combined chalcones and monoterpenes. These synthetic approaches also yielded various unnatural chalcone-monoterpene derivatives (14-23). The inhibitory effects on protein tyrosine phosphatase 1B (PTP1B) of both naturally isolated and synthetically obtained compounds were evaluated. Compounds 4, 9, 13, and 16b exhibited potent PTP1B inhibitory activity, with IC50 values ranging from 0.9 ± 0.2 to 3.9 ± 0.7 µM. The enantiomers (+)-4 and (-)-16b showed enhanced activity compared to their respective enantiomers. Kinetic studies indicate that all active compounds inhibit PTP1B through mixed mechanisms, and molecular docking simulations agree with the experimental assays on PTP1B. Our results suggest that chalcone-meroterpene adducts from the buds of C. operculatus exhibit potential as antidiabetic agents, partly due to their PTP1B enzyme inhibition.


Asunto(s)
Monoterpenos , Proteína Tirosina Fosfatasa no Receptora Tipo 1 , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Estructura Molecular , Monoterpenos/farmacología , Monoterpenos/química , Monoterpenos/aislamiento & purificación , Chalconas/farmacología , Chalconas/química , Chalconas/aislamiento & purificación , Chalcona/farmacología , Chalcona/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Humanos , Syzygium/química
7.
Phys Chem Chem Phys ; 26(26): 18449-18458, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38916072

RESUMEN

In this study, we developed a high-performance non-enzymatic electrochemical sensor based on urchin-like CoP3/Cu3P heterostructured nanorods supported on a three-dimensional porous copper foam, namely, CoP3/Cu3P NRs/CF, for the detection of dopamine. Benefiting from the promising intrinsic catalytic activities of CoP3 and Cu3P, urchin-like microsphere structures, and a large electrochemically active surface area for exposing numerous accessible catalytic active sites, the proposed CoP3/Cu3P NRs/CF shows extraordinary electrochemical response towards the electrocatalytic oxidation of dopamine. As a result, the CoP3/Cu3P NRs/CF sensing electrode has a broad detection window (from 0.2 to 2000 µM), low detection limit (0.51 µM), high electrochemical sensitivity (0.0105 mA µM-1 cm-2), excellent selectivity towards dopamine in the coexistence of some interfering species, and good stability for dopamine determination. More importantly, the CoP3/Cu3P NRs/CF catalyst also exhibits excellent catalytic activity, sensitivity, and selectivity for dopamine detection under simulated human body conditions at a physiological pH of 7.25 (0.1 M PBS) at 36.6 °C.


Asunto(s)
Cobre , Dopamina , Técnicas Electroquímicas , Nanotubos , Dopamina/análisis , Dopamina/química , Cobre/química , Técnicas Electroquímicas/métodos , Nanotubos/química , Porosidad , Catálisis , Cobalto/química , Electrodos , Límite de Detección , Oxidación-Reducción
9.
Fitoterapia ; 177: 106083, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38897253

RESUMEN

In an extensive screening endeavor for anti-coronaviral compounds, we examined 824 tropical plant extracts from the Annonaceae and Rutaceae families. The screening identified an ethyl acetate extract from the aerial parts of Miliusa balansae for its potent inhibitory activity against Human coronavirus HCoV-229E. Subsequent bioassay-guided fractionation of this extract revealed two unreported miliusanes including a complex dimeric structure and seven known compounds, comprising miliusane XXXVI, (+)-miliusol, bistyryls, styryl-pyranones, and the flavonoid rhamnetin. The absolute configuration of the new dimeric miliusane was determined by X-ray crystallography and a putative biogenetic origin was proposed. Investigation of the antiviral effect of these nine phytochemicals within HCoV-229E-infected Huh-7 cells showed that (+)-miliusol and miliusane XXXVI exert antiviral activity at non-cytotoxic concentrations, with IC50 values of 1.15 µM and 19.20 µM, respectively. Furthermore, these compounds significantly inhibited SARS-CoV-2 infection in Vero cells, presenting IC50 values of 11.31 µM for (+)-miliusol and 17.92 µM for miliusane XXXVI. Additionally, both compounds exhibited a potent antiviral effect against the emergent mosquito-borne Zika virus, with IC50 values of 1.34 µM and 23.45 µM, respectively. Time-of-addition assays suggest that their mechanism of action might target later stages of the viral cycle, indicating potential modulation of specific cellular pathways. These findings reinforce the invaluable contribution of medicinal flora as reservoirs of natural antiviral agents and emphasize their prospective role in combatting viruses of medical interest.


Asunto(s)
Antivirales , Antivirales/farmacología , Antivirales/aislamiento & purificación , Antivirales/química , Células Vero , Chlorocebus aethiops , Humanos , Animales , Estructura Molecular , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Componentes Aéreos de las Plantas/química , Rutaceae/química , SARS-CoV-2/efectos de los fármacos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Annonaceae/química
10.
J Colloid Interface Sci ; 670: 12-27, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38749379

RESUMEN

A new catalyst has been developed that utilizes molybdenum oxide (MoO3)/nickel molybdenum oxide (NiMoO4) heterostructured nanorods coupled with Pt ultrafine nanoparticles for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) toward industrial-grade water splitting. This catalyst has been synthesized using a versatile approach and has shown to perform better than noble-metals catalysts, such as Pt/C and RuO2, at industrial-grade current level (≥1000 mA·cm-2). When used simultaneously as a cathode and anode, the proposed material yields 10 mA·cm-2 at a remarkably small cell voltage of 1.55 V and has shown extraordinary durability for over 50 h. Density functional theory (DFT) calculations have proved that the combination of MoO3 and NiMoO4 creates a metallic heterostructure with outstanding charge transfer ability. The DFT calculations have also shown that the excellent chemical coupling effect between the MoO3/NiMoO4 and Pt synergistically optimize the charge transfer capability and Gibbs free energies of intermediate species, leading to remarkably speeding up the reaction kinetics of water electrolysis.

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