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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.
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.

4.
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.

5.
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
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
8.
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.
Dermatol Surg ; 50(9): 847-850, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38722745

RESUMEN

BACKGROUND: Chemical reconstruction of skin scars (CROSS) using high concentration trichloroacetic acid (TCA) is a safe, effective, and low-cost treatment for ice pick acne scars. OBJECTIVE: To compare the efficacy and effectiveness of the CROSS technique using 50% TCA and 80% TCA for treating ice pick scars. MATERIALS AND METHODS: A nonrandomized, single-blinded, and self-controlled clinical trial was undertaken. Four CROSS sessions were conducted using 50% TCA on the left hemiface and 80% TCA on the right hemiface. The E' chelle d'Evaluation Clinique des Cicatrices d'Acne (ECCA) acne grading scale was used to assess the scars pretreatment and posttreatment. Complications were evaluated after each session. RESULTS: Thirty-one patients participated in our study. Significant differences were found between pretreatment and posttreatment ECCA scores ( p < .0001) on both hemifaces. Scores were significantly lower on the side treated with 80% TCA; however, there was no statistical significance in mean ECCA score differences (pretreatment minus posttreatment) between the 2 treatment sides. The adverse events were more serious on the sides treated with 80% TCA. CONCLUSION: The CROSS method using TCA was well-tolerated and effective for treating ice pick acne scars. Less severe complications were associated with 50% TCA, whereas efficacy was the same as 80% TCA.


Asunto(s)
Acné Vulgar , Cáusticos , Cicatriz , Ácido Tricloroacético , Humanos , Ácido Tricloroacético/administración & dosificación , Ácido Tricloroacético/efectos adversos , Acné Vulgar/complicaciones , Acné Vulgar/tratamiento farmacológico , Cicatriz/etiología , Cicatriz/terapia , Cicatriz/tratamiento farmacológico , Femenino , Masculino , Adulto , Cáusticos/administración & dosificación , Método Simple Ciego , Adulto Joven , Resultado del Tratamiento , Adolescente
11.
Sci Prog ; 107(2): 368504241253675, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38807531

RESUMEN

Camptothecin (CPT) is an important alkaloid used for anticancer treatment. It is mainly produced by two endangered and overharvested Camptotheca acuminata and Nothapodytes nimmoniana plants. Endophytic fungi are promising alternative sources for CPT production. In the present study, fungi residing within explants of Ixora chinensis were isolated and their CPT-producing capability of their endophytes was verified via thin-layer chromatography, high-performance liquid chromatography, liquid chromatography/high resolution mass spectrometry, and nuclear magnetic resonance analyses and compared with standards. In addition, MTT and sulforhodamine B assays were selected to test the anticancer effect. The endophytic fungi collection of 62 isolates were assigned to 11 genera, with four common genera (Diaporthe, Phyllosticta, Colletotrichum, and Phomopsis) and seven less common genera (Penicillium, Botryosphaeria, Fusarium, Pestalotiopsis, Aspergillus, and Didymella). Moreover, the anticancer activity of extracts was assessed against human lung carcinoma (A549). Among eight potential extracts, only Penicillium sp. I3R2 was found to be a source of CPT, while the remaining seven extracts have not been discovered potential secondary compounds. Thus, other prominent endophytic fungi might be potential candidates of phytochemicals with anticancer properties.


Asunto(s)
Antineoplásicos , Camptotecina , Endófitos , Hongos , Humanos , Camptotecina/farmacología , Camptotecina/química , Camptotecina/biosíntesis , Endófitos/metabolismo , Endófitos/aislamiento & purificación , Endófitos/química , Hongos/aislamiento & purificación , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Células A549 , Línea Celular Tumoral
12.
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.

13.
Health Policy Plan ; 39(6): 541-551, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38597872

RESUMEN

The prevalence of common perinatal mental disorders in Vietnam ranges from 16.9% to 39.9%, and substantial treatment gaps have been identified at all levels. This paper explores constraints to the integration of maternal and mental health services at the primary healthcare level and the implications for the health system's responsiveness to the needs and expectations of pregnant women with mental health conditions in Vietnam. As part of the RESPONSE project, a three-phase realist evaluation study, we present Phase 1 findings, which employed systematic and scoping literature reviews and qualitative data collection (focus groups and interviews) with key health system actors in Bac Giang province, Vietnam, to understand the barriers to maternal mental healthcare provision, utilization and integration strategies. A four-level framing of the barriers to integrating perinatal mental health services in Vietnam was used in reporting findings, which comprised individual, sociocultural, organizational and structural levels. At the sociocultural and structural levels, these barriers included cultural beliefs about the holistic notion of physical and mental health, stigma towards mental health, biomedical approach to healthcare services, absence of comprehensive mental health policy and a lack of mental health workforce. At the organizational level, there was an absence of clinical guidelines on the integration of mental health in routine antenatal visits, a shortage of staff and poor health facilities. Finally, at the provider level, a lack of knowledge and training on mental health was identified. The integration of mental health into routine antenatal visits at the primary care level has the potential help to reduce stigma towards mental health and improve health system responsiveness by providing services closer to the local level, offering prompt attention, better choice of services and better communication while ensuring privacy and confidentiality of services. This can improve the demand for mental health services and help reduce the delay of care-seeking.


Asunto(s)
Servicios de Salud Materna , Servicios de Salud Mental , Atención Primaria de Salud , Humanos , Vietnam , Atención Primaria de Salud/organización & administración , Femenino , Servicios de Salud Mental/organización & administración , Embarazo , Servicios de Salud Materna/organización & administración , Accesibilidad a los Servicios de Salud , Grupos Focales , Trastornos Mentales/terapia , Prestación Integrada de Atención de Salud/organización & administración , Investigación Cualitativa , Estigma Social
14.
Molecules ; 29(7)2024 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-38611738

RESUMEN

The Streptomyces strain G222, isolated from a Vietnamese marine sediment, was confidently identified by 16S rRNA gene sequencing. Its AcOEt crude extract was successfully analyzed using non-targeted LC-MS/MS analysis, and molecular networking, leading to a putative annotation of its chemical diversity thanks to spectral libraries from GNPS and in silico metabolite structure prediction obtained from SIRIUS combined with the bioinformatics tool conCISE (Consensus Annotation Propagation of in silico Elucidations). This dereplication strategy allowed the identification of an interesting cluster of a series of putative cyclic and linear lipopeptides of the lichenysin and surfactin families. Lichenysins (3-7) were isolated from the sub-fraction, which showed significant anti-biofilm activity against Pseudomonas aeruginosa MUC-N1. Their structures were confirmed by detailed 1D and 2D NMR spectroscopy (COSY, HSQC, HMBC, TOCSY, ROESY) recorded in CD3OH, and their absolute configurations were determined using the modified Marfey's method. The isolated lichenysins showed anti-biofilm activity at a minimum concentration of 100 µM. When evaluated for antibacterial activity against a panel of Gram-positive and Gram-negative strains, two isolated lichenysins exhibited selective activity against the MRSA strain without affecting its growth curve and without membranotropic activity. This study highlights the power of the MS/MS spectral similarity strategy using computational methods to obtain a cross-validation of the annotated molecules from the complex metabolic profile of a marine sediment-derived Streptomyces extract. This work provides the first report from a Streptomyces strain of combined cyclic and linear lichenysins and surfactins, known to be characteristic compounds of the genus Bacillus.


Asunto(s)
Sedimentos Geológicos , Espectrometría de Masas en Tándem , Humanos , Cromatografía Liquida , ARN Ribosómico 16S , Vietnam
15.
Sci Data ; 11(1): 321, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38548727

RESUMEN

Flexible bronchoscopy has revolutionized respiratory disease diagnosis. It offers direct visualization and detection of airway abnormalities, including lung cancer lesions. Accurate identification of airway lesions during flexible bronchoscopy plays an important role in the lung cancer diagnosis. The application of artificial intelligence (AI) aims to support physicians in recognizing anatomical landmarks and lung cancer lesions within bronchoscopic imagery. This work described the development of BM-BronchoLC, a rich bronchoscopy dataset encompassing 106 lung cancer and 102 non-lung cancer patients. The dataset incorporates detailed localization and categorical annotations for both anatomical landmarks and lesions, meticulously conducted by senior doctors at Bach Mai Hospital, Vietnam. To assess the dataset's quality, we evaluate two prevalent AI backbone models, namely UNet++ and ESFPNet, on the image segmentation and classification tasks with single-task and multi-task learning paradigms. We present BM-BronchoLC as a reference dataset in developing AI models to assist diagnostic accuracy for anatomical landmarks and lung cancer lesions in bronchoscopy data.


Asunto(s)
Broncoscopía , Neoplasias Pulmonares , Humanos , Inteligencia Artificial , Neoplasias Pulmonares/diagnóstico por imagen , Tórax/diagnóstico por imagen , Puntos Anatómicos de Referencia/diagnóstico por imagen
16.
Chemistry ; 30(26): e202400160, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38446081

RESUMEN

Hydrogen bonds are a versatile tool for creating fibrous, bottlebrush-like assemblies of polymeric building blocks. However, a delicate balance of forces exists between the steric repulsion of the polymer chains and these directed supramolecular forces. In this work we have systematically investigated the influence of structural parameters of the attached polymers on the assembly behaviour of benzene trisurea (BTU) and benzene tris(phenylalanine) (BTP) conjugates in water. Polymers with increasing main chain lengths and different side chain sizes were prepared by reversible addition-fragmentation chain-transfer (RAFT) polymerization of hydroxyethyl acrylate (HEA), tri(ethylene glycol) methyl ether acrylate (TEGA) and oligo(ethylene glycol) methyl ether acrylate (OEGA). The resulting structures were analyzed using small angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). Both BTU and BTP formed fibres with PHEA attached, but a transition to spherical morphologies was observed at degrees of polymerisation (DP) of 70 and above. Overall, the main chain length appeared to be a dominating factor in inducing morphology transitions. Increasing the side chain size generally had a similar effect but mainly impeded any aggregation as is the case of POEGA. Interestingly, BTP conjugates still formed fibres, suggesting that the stronger intermolecular interactions can compensate partially for the steric repulsion.

17.
Access Microbiol ; 6(1)2024.
Artículo en Inglés | MEDLINE | ID: mdl-38361655

RESUMEN

Xanthomonas euvesicatoria the primary causal agent of bacterial spot of pepper (BSP), poses a significant global challenge, resulting in severe defoliation and yield losses for pepper growers. We present the whole genome sequences of eight X. euvesicatoria strains associated with BSP in Vietnam. These genomes contribute to representation of pepper production regions in the global sample of X. euvesicatoria genomes, enabling the development of precise global disease management strategies.

18.
BMJ Open ; 14(2): e075976, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38423779

RESUMEN

OBJECTIVE: Pre-exposure prophylaxis (PrEP) was introduced in Viet Nam in 2017, but data on oral PrEP preference and effective use beyond 3 months are limited. We aimed to evaluate PrEP preferences for PrEP, factors influencing uptake, choice and effective use, as well as barriers to PrEP. METHODS: This is a prospective cohort study in Can Tho, Viet Nam. Participants who were eligible for PrEP and provided informed consent were interviewed at baseline on demographic information, willingness to pay, reasons for choosing their PrEP regimen and the anticipated difficulties in taking PrEP and followed up at 3 months, 6 months and 12 months after PrEP initiation. FINDINGS: Between May 2020 and April 2021, 926 individuals at substantial risk for HIV initiated PrEP. Of whom 673 (72.7%) choose daily PrEP and 253 (27.3%) choose event-driven (ED)-PrEP. The majority of participants were men (92.7%) and only 6.8% were women and 0.5% were transgender women. Median participant age was 24 years (IQR 20-28) and 84.7% reported as exclusively same-sex relationship. The three most common reasons for choosing daily PrEP were effectiveness (24.3%) and unplanning for sex (22.9%). Those opting for ED-PrEP also cited effectiveness (22.7%), as well as convenience (18.0%) and easier effective use (12.0%). Only 7.8% of PrEP users indicated they were unwilling to pay for PrEP and 76.4% would be willing to pay if PrEP were less than US$15 per month. The proportion of user effectively using PrEP at 12 months was 43.1% and 99.2% in daily PrEP and ED-PrEP users, respectively. CONCLUSIONS: ED-PrEP was preferred by more than a quarter of 23.5% of the participants and there was little concern about potential adverse events. High rates of effective use were reported by ED-PrEP users. Future research to inform implementation of PrEP in Viet Nam is needed to develop ways of measuring adherence to ED-PrEP more accurately and to understand and address difficulties in taking daily PrEP use.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Profilaxis Pre-Exposición , Humanos , Masculino , Femenino , Adulto Joven , Adulto , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Homosexualidad Masculina , Estudios Prospectivos , Vietnam , Cumplimiento de la Medicación , Fármacos Anti-VIH/uso terapéutico
19.
Digestion ; 105(2): 140-148, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38190818

RESUMEN

INTRODUCTION: Severe and extensive gastric atrophy, extensive or incomplete gastric intestinal metaplasia, and gastric dysplasia are considered high-risk gastric precancerous lesions (HGPLs). Endoscopic findings based on the endoscopic Kyoto classification (EKC) and the Kimura-Takemoto classification (KTC) have been reported to be significantly associated with HGPLs. This study aimed to compare these two classifications in predicting active Helicobacter pylori (H. pylori) infection and HGPLs. METHODS: This is a cross-sectional study conducted on naïve dyspeptic patients who underwent upper gastrointestinal endoscopy at a tertiary hospital. Endoscopic findings were scored according to the EKC and KTC. Mapping biopsies were taken, and H. pylori infection was determined using a locally validated rapid urease test and histology. The performance of EKC was compared with that of KTC using the area under the receiver operating characteristic curve (AUC) in predicting active H. pylori infection and HGPLs. RESULTS: There were 292 patients with a median age of 46 and a male-to-female ratio of 1:1. The rates of active H. pylori infection and HGPLs were 61.3% and 14.0%, respectively. The EKC was better than the KTC in predicting active H. pylori infection (AUC: 0.771 vs. 0.658, respectively; p < 0.001). However, these two classifications had comparable performance in predicting HGPLs (AUC: 0.792 vs. 0.791, respectively; p = 0.956). CONCLUSION: Compared to EKC, KTC is inferior in predicting active H. pylori infection but has comparable performance in predicting HGPLs.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Lesiones Precancerosas , Neoplasias Gástricas , Humanos , Masculino , Femenino , Estudios Transversales , Gastroscopía , Estómago/patología , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patología , Infecciones por Helicobacter/patología , Lesiones Precancerosas/diagnóstico , Lesiones Precancerosas/patología , Metaplasia/diagnóstico por imagen , Mucosa Gástrica/diagnóstico por imagen , Mucosa Gástrica/patología
20.
Fitoterapia ; 173: 105826, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38219842

RESUMEN

Five undescribed lignans, cleiseberharnins A-D (1-4), cleiseberharside A (5) were isolated from the fruits of Cleistanthus eberhartii (Phyllanthaceae), together with six known aryltetralin lignans, cleistantoxin (6), picroburseranin (7), neocleistantoxin (8), 7-hydroxypicropolygamain (9), cleisindoside D (10), and cleisindoside A (11). Their structures and relative configurations were established by analysis of HRESIMS and NMR data, and quantum chemical calculations of JH,H coupling constants. The absolute configurations of 1-5 were determined by analysis of their experimental CD spectra and comparison with calculated electronic circular dichroism (ECD) spectra. All compounds (1-11) were evaluated for their cytotoxicity against KB, MCF-7, HepG-2, and Lu-1 human cancer cell lines. Among the tested compounds, compounds 6 and 7 showed strong activity against KB, MCF7, HepG2 and Lu-1 cell lines with IC50 values in the range of 0.02-0.62 µM. Compound 1 showed activity against three cancer cell lines KB, HepG2, and Lu-1 with IC50 values of 6.98, 7.61 and 11.75 µM, respectively. Compound 2 exhibited a selective inhibition with moderate cytotoxicity against Lu-1 with IC50 value of 15.30 µM. Compounds 4, 5 and 9 showed moderate activity against the three cancer cell lines with IC50 values in the range of 8.73-19.70 µM.


Asunto(s)
Antineoplásicos Fitogénicos , Antineoplásicos , Lignanos , Malpighiales , Humanos , Línea Celular Tumoral , Frutas/química , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Estructura Molecular , Lignanos/farmacología , Lignanos/química
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