Oleanane-type saponins from Lysimachia laxa Baudo and their anti-bacterial activities.

Seven new oleanane-type triterpene saponins, lysimaponins A-G, were isolated from aerial parts of Lysimachia laxa Baudo. Their chemical structures have been elucidated by analysis of spectroscopic and chemical methods. All compounds were evaluated for their anti-bacterial effects against Microcystis aeruginosa, Vibrio parahaemolyticus, V. harveyi, V. vulinificus, V. cholerae, and V. alginolyticus. All compounds showed potent anti-bacterial activities against the cyanobacteria M. aeruginosa with IC50 values ranging from 14.4 ± 1.2 to 35.3 ± 2.2 µg/mL. Compounds 1, 2, 4-7 inhibited V. parahaemolyticus with MIC values ranging from 64 to 256 µg/mL. The results suggested that saponins from L. laxa could be potential anti-cyanobacteria agents.

Investigating the effectiveness of web-based HIV self-test distribution and linkage to HIV treatment and PrEP among groups at elevated risk of HIV in Viet Nam provinces: a mixed-methods analysis of implementation from pilot to scale-up.

INTRODUCTION: In Viet Nam, key populations (KPs) face barriers accessing HIV services. Virtual platforms can be leveraged to increase access for KPs, including for HIV self-testing (HIVST). This study compares reach and effectiveness of a web-based HIVST intervention from pilot to scale-up in Viet Nam. METHODS: A mixed-methods explanatory sequential design used cross-sectional and thematic analysis. The pilot launched in Can Tho in November 2020, followed by Hanoi and Nghe An in April 2021. Scale-up included Can Tho and Nghe An, with 21 novel provinces from April to December 2022. After risk assessment, participants registered on the website, receiving HIVST (OraQuick®) by courier, peer educator or self-pick-up. Test result reporting and completing satisfaction surveys were encouraged. Intervention reach was measured through numbers accessing the testing, disaggregated by demographics, and proportion of individuals reporting self-testing post-registration. Effectiveness was measured through numbers reporting self-test results, testing positive and linking to care, and testing negative and using HIVST to manage pre-exposure prophylaxis (PrEP) use. Thematic content analysis of free-text responses from the satisfaction survey synthesized quantitative outcomes. RESULTS: In total, 17,589 participants registered on the HIVST website; 11,332 individuals ordered 13,334 tests. Participants were generally young, aged <25 years (4309/11,332, 38.0%), male (9418/11,332, 83.1%) and men who have sex with men (6437/11,332, 56.8%). Nearly half were first-time testers (5069/11,332, 44.9%). Scale-up participants were two times more likely to be assigned female at birth (scale-up; 1595/8436, 18.9% compared to pilot; 392/3727, 10.5%, p < 0.001). Fewer test results were reported in scale-up compared with pilot (pilot: 3129/4140, 75.6%, scale-up: 5811/9194, 63.2%, p < 0.001). 6.3% of all tests were reactive (pilot: 176/3129, 5.6% reactive compared to scale-up: 385/5811, 6.6% reactive, p = 0.063); of which most linked to care (509/522, 97.5%). One-fifth of participants with a negative test initiated or continued PrEP (pilot; 19.8%, scale-up; 18.5%, p = 0.124). Thematic analysis suggested that community delivery models increased programmatic reach. Live chat may also be a suitable proxy for staff support to increase result reporting. CONCLUSIONS: Web-based self-testing in Viet Nam reached people at elevated risk of HIV, facilitating uptake of anti-retroviral treatment and direct linkage to PrEP initiations. Further innovations such as the use of social-network testing services and incorporating features powered by artificial intelligence could increase the effectiveness and efficiency of the approach.

Five New Furostanol Glycosides from the Fruits of Tribulus terrestris with NO Production Inhibitory Activity.

Eight furostanol glycosides including five undescribed compounds, named tribufurostanosides A-E (1-5), and three known ones (6-8) were isolated from the fruits of Tribulus terrestris L. Their chemical structures were determined by the IR, HR-ESI-MS, 1D-, and 2D-NMR spectra. Furostanols 1-8 significantly inhibited nitric oxide production in LPS activated RAW 264.7 cells with IC50 values ranging from 14.2 to 64.7 µM, compared to that of the positive control compound, dexamethazone (IC50 13.6 µM).

Tributelosides A-D: Four Undescribed Spirostan Glycosides Isolated from the Branches and Leaves of Tribulus terrestris with Their NO Production Inhibitory Activity in LPS Activated RAW 264.7 Cells.

Four undescribed spirostan glycosides, (25S)-5α-spirostan- 12-one-2α,3ß-diol-3-O-ß-D-glucopyranosyl-(1→4)-ß-D-galactopyranoside (1), (25S)-5α-spirostan-12-one-2α,3ß-diol-3-O-ß-D-galatopyranosyl-(1→2)-ß-D-glucopyranosyl- (1→4)-ß-D-galactopyranoside (2), (25S)-5α-spirostan-12-one-2α,3ß-diol-3-O-ß-D-glucopyranosyl-(1→2)-[ß-D-glucopyranosyl-(1→3)]-ß-D-glucopyranosyl-(1→4)-ß-D-galactopyranoside (3), and hecogenin 3-O-ß-D-glucopyranosyl-(1→3)-[ß-D-xylopyranosyl-(1→2)]-ß-D-glucopyranosyl-(1→4)-[α-L-rhamnopyranosyl-(1→2)]-ß-D-galactopyranoside (4), together with eleven known compounds (5-15) were isolated from the branches and leaves of Tribulus terrestris. Their chemical structures were established through spectroscopic methods, including HR-ESI-MS, 1D-, and 2D-NMR spectra. Preliminary biological evaluation on NO production inhibitory activity in LPS activated RAW 264.7 cells showed that compounds 1-3, 5, and 6 had significant inhibitory effects with IC50 values ranging from 2.4 to 18.3 µM, compared to that of the positive control compound, dexamethazone (IC50 13.6 µM).

Hericium VN, an undescribed compound isolated from Hericium erinaceus and its cytotoxic activity on human brain astrocytoma.

Hericium erinaceus is a species of mushroom with high nutritional value that is used mainly as food in tropical countries. Phytochemical study of H. erinaceus led to the isolation of an undescribed compound, named as hericium VN (1), together with nine known compounds, 1-(2-formyl-1-pyrrolyl)butanoic acid (2), herierin III (3), 5'-(methylthio)adenosine (4), adenosine (5), nicotinic acid (6), (22E,24R)-5α,8α-epidioxyergosta-6,9(11),22-trien-3ß-ol (7), 5α,8α-peroxycerevisterol (8), (22E,24R)-5α,8α-epidioxy-egosta-6,22-diene 3-O-ß-D-glucopyranoside (9), and cerevisterol (10) based on extensive analyses of HR-ESI-MS, 1D and 2D NMR spectra. The absolute configuration of compound 1 was determined by experimental combined with calculated electronic circular dichroism spectra. Compound 7 exhibited cytotoxic effects against brain tumor cell line CCF-STTG1 with the IC50 value of 15.50 µM, compared to that of the positive control compound, doxorubicin, which showed IC50 value of 15.84 µM.

Discovery of a novel natural compound, vitekwangin B, with ANO1 protein reduction properties and anticancer potential.

Background: Prostate cancer and non-small cell lung cancer (NSCLC) present significant challenges in the development of effective therapeutic strategies. Hormone therapies for prostate cancer target androgen receptors and prostate-specific antigen markers. However, treatment options for prostatic small-cell neuroendocrine carcinoma are limited. NSCLC, on the other hand, is primarily treated with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors but exhibits resistance. This study explored a novel therapeutic approach by investigating the potential anticancer properties of vitekwangin B, a natural compound derived from Vitex trifolia. Methods: Vitekwangin B was chromatographically isolated from the fruits of V. trifolia. ANO1 protein levels in prostate cancer and NSCLC cells were verified and evaluated again after vitekwangin B treatment. Results: Vitekwangin B did not inhibit anoctamin1 (ANO1) channel function but significantly reduced ANO1 protein levels. These results demonstrate that vitekwangin B effectively inhibited cancer cell viability and induced apoptosis in prostate cancer and NSCLC cells. Moreover, it exhibited minimal toxicity to liver cells and did not affect hERG channel activity, making it a promising candidate for further development as an anticancer drug. Conclusion: Vitekwangin B may offer a new direction for cancer therapy by targeting ANO1 protein, potentially improving treatment outcomes in patients with prostate cancer and NSCLC. Further research is needed to explore its full potential and overcome existing drug resistance challenges.

Discovery of new triterpene glycosides from Dendrobium officinale with their α-glucosidase and α-amylase inhibitory activity.

In this study, seven new pentacyclic triterpene glycosides, named dendrocinaosides A-G (1-7), and six known ones (8-13) were isolated from the whole plants of Dendrobium officinale. Their structures were determined by analyses of HR-ESI-MS, 1D and 2D NMR spectra. Compounds 1-4, 8, and 9 potentially inhibited α-glucosidase and α-amylase activities with the IC50 values ranging from 31.3 ± 2.2 to 42.4 ± 2.5 µM for anti α-glucosidase and from 36.5 ± 1.8 to 56.4 ± 2.0 µM for anti α-amylase activities, respectively, which were lower than that of the positive control, acarbose, showing IC50 values of 47.1 ± 1.4 µM for anti α-glucosidase and 145.7 ± 2.2 µM for anti α-amylase.

Four Undescribed Stilbenoid Derivatives from the Aerial Parts of Dendrobium officinale with their α-Glucosidase and α-Amylase Inhibitory Activity.

In this study, four undescribed bibenzyl derivatives (1-4), together with seven known compounds (5-11) were isolated from the aerial parts of Dendrobium officinale. Their chemical structures were determined to be (7'S,8'S) -9''-acetyldendrocandin U (1), (7'S,8'S) -4'-methoxydendrocandin T (2), (7'R,8'S) -dendrocandin B (3), (1S,2R) -5'''-methoxydendrofindlaphenol C (4) by analyzing of the spectroscopic data including HR-ESI-MS, 1D-, and 2D-NMR spectra. The absolute configurations of compounds 1-4 were determined by the electronic circular dichroism (ECD) spectra. Compounds 1-3, 5, 10 and 11 inhibited α-glucosidase with the IC50 values ranging from 56.3 to 165.3 µM, compounds 1-3, 5, 7-10 inhibited α-amylase with the IC50 values ranging from 65.2 to 177.6 µM.

Undescribed (2-7')-neolignans and polyoxygenated cyclohexene glycosides from the aerial parts of Piper mutabile C. DC. and their inhibitory effects on nitric oxide production.

A phytochemical study of the aerial parts of Piper mutabile C. DC. revealed seven undescribed compounds [two (2-7')-neolignans and five polyoxygenated cyclohexene glycosides] and six known propenylcatechol derivatives. The chemical structures of the isolated compounds were elucidated by extensive HR-ESI-MS and NMR analyses, as well as comparison with the literature. The absolute configurations of the (2-7')-neolignans were confirmed by GIAO 13C NMR calculations with a sorted training set strategy and TD-DFT calculation ECD spectra. The (2-7')-neolignans and polyoxygenated cyclohexene glycosides are unusual in natural sources. Undescribed neolignans 1 and 2 inhibited NO production in RAW 264.7 cells, with respective IC50 values of 14.4 and 9.5 µM.

Undescribed sesquiterpene-diterpene heterodimers from the fruits of Aphanamixis polystachya selectively modulate inflammatory markers in RAW 264.7 cells.

Aphanapolystachones A-C (1-3), three undescribed sesquiterpene-diterpene heterodimers, were obtained from the fruits of Aphanamixis polystachya. Their structures and absolute configurations were identified by extensive analysis of HR-ESI-MS, NMR, experimental and TD-DFT calculated ECD spectra. The biosynthetic pathway of them was also proposed, which is produced by key intermolecular Diels-Alder [4 + 2]-cycloaddition reaction between a guaiane sesquiterpene and an acyclic diterpene. Compounds 1-3 inhibited NO production in LPS activated RAW 264.7 cells with the IC50 values of 1.7 ± 0.2, 3.0 ± 0.3, 5.3 ± 0.3 µM, respectively, lower than that of the positive control L-NMMA (31.5 ± 2.6 µM). In addition, compounds 1-3 significantly reduced IL-6 secretion at diluted concentration of 0.4 µM.

Four Undescribed compounds Isolated from the Aerial Parts of Phyllanthus cochinchinensis with Antimicrobial Activity and NO Production Inhibitory Activity in LPS Activated RAW 264.7 Cells.

Four previously undescribed compounds named phyllancosides A and B (1 and 2), and phyllancochines A and B (3 and 4) together with ten known compounds (5-14) were isolated from the aerial parts of Phyllanthus cochinchinensis Spreng. Their chemical structures were elucidated on the basis of comprehensive analysis of IR, HR-ESI-MS, 1D and 2D NMR spectra. The absolute configurations of 1 and 2 were determined by electronic circular dichroism (ECD) spectra. Compounds 3, 4, and 10 showed antimicrobial activity against E. faecalis, S. aureus, and B. cereus with the MIC values in range of 32-256 µg/mL. Compound 11 inhibited E. faecalis and B. cereus, and 7 inhibited S. aureus with the MIC values in range of 64-128 µg/mL. In addition, compounds 1, 3, 4, 8, and 9 showed significantly NO production inhibitory activity in LPS activated RAW 264.7 cells with IC50 values ranging from 36.57 to 56.34 µM.

Undescribed Triterpenes from the Leaves of Syzygium myrsinifolium with Their α-Glucosidase and α-Amylase Inhibition Activity.

Two undescribed triterpenes, syzyfolium A (1) and syzyfolium B (2), together with twelve known compounds, terminolic acid (3), actinidic acid (4), piscidinol A (5), threo-dihydroxydehydrodiconiferyl alcohol (6), lariciresinol-4-O-ß-D-glucoside (7), icariol A2 (8), 14ß,15ß-dihydroxyklaineanone (9), garcimangosone D (10), (+)-catechin (11), myricetin-3-O-α-L-rhamnopyranoside (12), quercitrin (13), and 3, 4, 5-trimethoxyphenyl-(6'-O-galloyl)-O-ß-D-glucopyranoside (14) were isolated from the leaves of Syzygium myrsinifolium. Their chemical structures were determined by IR, HR-ESI-MS, 1D and 2D NMR spectra. Compounds 3 and 4 inhibited significantly α-glucosidase with IC50 values of 23.99 and 36.84, respectively, and compounds 1 and 2 inhibited significantly α-amylase with IC50 values of 35.48 and 43.65 µM, respectively.

Four New Steroidal Saponins from the Roots of Dracaena cambodiana with NO Production Inhibition Activity in LPS Activated RAW 264.7 Cells.

Seven steroidal saponins including three new 16,23-cyclocholestanes (1-3) and one new pregane (4) were isolated from the roots of Dracaena cambodiana Pierre ex Gagnep. Their chemical structures were elucidated to be (23R,25R)-26-O-ß-D-glucopyranosyl-16,23-cyclocholesta-5,17(20)-dien-22-one-3ß,16α,26-triol-3-O-α-L-rhamnopyranosyl-(1→2)-[α-L-rhamnopyranosyl-(1→3)]-ß-D-glucopyranoside (1), (23R,25R)-26-O-ß-D-glucopyranosyl-16,23-cyclocholesta-5,17,20(22)-trien-3ß,22,26-triol-3-O-α-L-rhamnopyranosyl-(1→3)-ß-D-glucopyranoside (2), (23R,25R)-16,23-cyclocholesta-5,16,20(22)-trien-3ß,22,26-triol-3-O-α-L-rhamnopyranosyl-(1→3)-ß-D-glucopyranoside (3), 3ß-[(O-α-L-rhamnopyranosyl-(1→3)-[α-L-rhamnopyranosyl-(1→2)]-ß-D-gluco-pyranosyl)oxy]-pregna-5,17(20)-diene-16-one-20-carboxylic acid 4''''-O-ß-D-glucopyranosylisopentyl ester (4), cambodianoside A (5), diosbulbiside C (6), and diosbulbiside D (7), by IR, HR-ESI-MS, 1D and 2D NMR spectra. Compounds 1 and 4-7 inhibited nitric oxide (NO) production in lipopolysaccharide activated RAW 264.7 cells with IC50 values ranging from 19.03±1.84 to 67.92±3.81 µM, whereas compounds 2 and 3 were inactive with IC50 values over 100 µM.

Interactions between climate change, urban infrastructure and mobility are driving dengue emergence in Vietnam.

Dengue is expanding globally, but how dengue emergence is shaped locally by interactions between climatic and socio-environmental factors is not well understood. Here, we investigate the drivers of dengue incidence and emergence in Vietnam, through analysing 23 years of district-level case data spanning a period of significant socioeconomic change (1998-2020). We show that urban infrastructure factors (sanitation, water supply, long-term urban growth) predict local spatial patterns of dengue incidence, while human mobility is a more influential driver in subtropical northern regions than the endemic south. Temperature is the dominant factor shaping dengue's distribution and dynamics, and using long-term reanalysis temperature data we show that warming since 1950 has expanded transmission risk throughout Vietnam, and most strongly in current dengue emergence hotspots (e.g., southern central regions, Ha Noi). In contrast, effects of hydrometeorology are complex, multi-scalar and dependent on local context: risk increases under either short-term precipitation excess or long-term drought, but improvements in water supply mitigate drought-associated risks except under extreme conditions. Our findings challenge the assumption that dengue is an urban disease, instead suggesting that incidence peaks in transitional landscapes with intermediate infrastructure provision, and provide evidence that interactions between recent climate change and mobility are contributing to dengue's expansion throughout Vietnam.

Three Undescribed Iridoid Derivatives Isolated from the Fruits of Vitex trifolia with Their Cytotoxic and Antimicrobial Activities.

Vitex trifolia L. is a medicinal plant and widely distributed in the northern mountainous areas of Vietnam. Phytochemical study on the fruits of this plant led to the isolation of nine iridoid derivatives (1-9) including three undescribed compounds (1-3). Their structures were elucidated to be 3''-hydroxyscrophuloside A1 (1), 3''-hydroxycallicoside D (2), 2'-p-hydroxybenzoylaucubin (3), 6'-p-hydroxybenzoylmussaenosidic acid (4), nishindaside (5), agnuside (6), 10-O-vanilloylaucubin (7), 6'-O-p-hydroxybenzoyl-gardoside (8), and buddlejoside B (9) based on extensive analyses of HR-ESI-MS, 1D and 2D NMR spectra. Compounds 1, 2, 4, and 8 significantly posessed anti-barterial activity against Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa strains with MIC values in range of 16-64 µg/mL. At concentration of 20 µM, compounds 1-9 did not show cytotoxic effects against human lung cancer cells (PC9).

Undescribed 2,9-deoxyflavonoids and flavonol-diamide [3+2] adduct from the leaves of Aglaia odorata Lour. Inhibit nitric oxide production.

Phytochemical study on the methanol extract of Aglaia odorata leaves resulted in the isolation of four previously undescribed compounds, including three 2,9-deoxyflavonoids and one flavonol-diamide [3 + 2] adduct, and 13 known compounds. The chemical structures of the four undescribed compounds were elucidated on the basis of their IR, HR-ESI-MS, 1D and 2D NMR, and ECD spectra. The results revealed an unprecedented 2,9-deoxyflavonoid framework, which was confirmed by TD-DFT, ECD, and GIAO 13C-NMR calculations using sorted training set methods. The 17 compounds were examined for their ability to inhibit NO production activity in cultured lipopolysaccharide-activated RAW264.7 cells with aglaodoratas A-C, odorine, and epi-odorine inhibiting NO production, with IC50 values in the range of 16.2-24.3 µM. The other investigated compounds had either weak or no activity.

Two new lignan glycosides from Acanthus ilicifoliusL. with their NO inhibition and cytotoxic activity.

A phytochemical investigation of the methanolic extract of aerial parts of the Acanthus ilicifolius led to the isolation of two new lignan glycosides, acaniliciosides A and B (1 and 2), together with ten known compounds (3-12). The structures of isolated compounds were elucidated based on HR-ESI-MS, 1D and 2D NMR spectroscopic data. The absolute configurations of two new compounds were established by CD spectra. With the exception of compound 12, other compounds inhibited NO production in LPS activated RAW264.7 cells with IC50 values of 2.14-28.18 µM, as potent as that of the positive control of NG-monomethyl-L-arginine acetate (L-NMMA, IC50 of 32.50 µM). In addition, compounds 5-8 showed cytotoxic effects against SK-LU-1 and HepG2 cell lines with the IC50 values ranging from 16.48 to 76.40 µM compared to the positive control (ellipticine) with the IC50 values ranging from 1.23 to 1.46 µM.

An economic evaluation of Wolbachia deployments for dengue control in Vietnam.

INTRODUCTION: Dengue is a major public health challenge and a growing problem due to climate change. The release of Aedes aegypti mosquitoes infected with the intracellular bacterium Wolbachia is a novel form of vector control against dengue. However, there remains a need to evaluate the benefits of such an intervention at a large scale. In this paper, we evaluate the potential economic impact and cost-effectiveness of scaled Wolbachia deployments as a form of dengue control in Vietnam-targeted at the highest burden urban areas. METHODS: Ten settings within Vietnam were identified as priority locations for potential future Wolbachia deployments (using a population replacement strategy). The effectiveness of Wolbachia deployments in reducing the incidence of symptomatic dengue cases was assumed to be 75%. We assumed that the intervention would maintain this effectiveness for at least 20 years (but tested this assumption in the sensitivity analysis). A cost-utility analysis and cost-benefit analysis were conducted. RESULTS: From the health sector perspective, the Wolbachia intervention was projected to cost US$420 per disability-adjusted life year (DALY) averted. From the societal perspective, the overall cost-effectiveness ratio was negative, i.e. the economic benefits outweighed the costs. These results are contingent on the long-term effectiveness of Wolbachia releases being sustained for 20 years. However, the intervention was still classed as cost-effective across the majority of the settings when assuming only 10 years of benefits. CONCLUSION: Overall, we found that targeting high burden cities with Wolbachia deployments would be a cost-effective intervention in Vietnam and generate notable broader benefits besides health gains.

Dimethylbutyrylated Dibenzocyclooctadiene Lignans from the Fruits of Schisandra cauliflora Inhibit NO Production in LPS-Activated RAW264.7 Cells.

From the fruits of Schisandra cauliflora, five new dimethylbutyrylated dibenzocyclooctadiene lignans, named schisandracaurins A-E, were isolated using separation and chromatographic techniques. Their structures were determined by extensive analyses of HR-ESI-MS, NMR, and ECD spectra. The schisandracaurins A-E potentially inhibited NO production in LPS-activated RAW264.7 cells with their IC50 values from 21.4 to 30.3 µM.

Dual Emission Carbon Dots for Simultaneous Detections of Pb2+ and Fe3+ Ions in Water Via Distinct Sensing Mechanisms.

Herein, dual-emission carbon dots (DE-CDs) were synthesized using a one-pot hydrothermal method. DE-CDs exhibited two well-separated peaks at 433 and 513 nm under ultraviolet excitation. The prepared DE-CDs offer selective detection of Fe3+ ions via inner filter effect (IFE) and Pb2+ ions via aggregation-induced enhancement (AIE). The obtained DE-CDs showed a good affinity for both Fe3+ and Pb2+ ions in the presence of various interfering ions. The limits of detection were 0.797 ppm and 4.739 ppm for Pb2+ and Fe3+, respectively. The finding reveals the huge potential of DE-CDs for the selective detection of multiple targets in one solution.