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1.
Chem Biodivers ; : e202401356, 2024 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-39343745

RESUMO

In this study, the volatile components of Erigeron sublyratus essential oils and their anti-inflammatory and cytotoxic activities were investigated for the first time. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that a total of 28 components were identified in the root and aerial part essential oils. Among them, cis-lachnophyllum ester (53.4-64.2%), followed by germacrene D (5.6-8.6%), trans-ß-ocimene (2.6-7.5%), ß-caryophyllene (4.7-6.8%), ß-myrcene (2.0-6.3%), and (E)-ß-famesene (4.8-5.0%) were principal components. The root essential oil significantly inhibited nitric oxide (NO) production on LPS-induced RAW264.7 cells (IC50 = 1.41 ± 0.10 µg/mL) as compared to standard, dexamethasone (IC50 = 5.43 ± 0.54 µg/mL). Besides, both root and aerial part essential oils exhibited cytotoxic activity against MCF-7, SK-LU-1, and HepG2 (IC50 from 1.11 ± 0.04 to 1.70 ± 0.05 µg/mL). Molecular docking simulation results show that (E)-ß-farnesene exhibits the strongest binding energy among the studied compounds with the VEGFR-2 enzyme (ΔG = -7.295 kcal/mol), while δ-cadinene demonstrates the strongest affinity (ΔG = -8.047 kcal/mol) towards the COX-2 enzyme. Furthermore, hydrophobic interactions were indicated to be the main contributors to the binding ability in the studied protein-ligand complex. These findings proposed that E. sublyratus can be exploited for its anti-inflammatory and anti-cytotoxicity potential.

2.
Arch Virol ; 167(10): 2011-2026, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35794492

RESUMO

We conducted nucleotide and amino acid sequence alignment and phylogenetic analysis of porcine circovirus ORF2 (Cap protein) from 17 PCV2-positive clinical samples from nine different northern Vietnamese provinces (Mar 2018-Nov 2020), four local vaccines, and 77 reference strains. We identified one PCV2a (1/17 = 5.9%), five PCV2b (5/17 = 29.9%), and 11 PCV2d (11/17 = 64.7%) isolates, while only PCV2d was detected in 2020. Timeline analysis indicated an increasing predominance of PCV2d nationwide (2018-2020). With strong nodal support (98% for nucleotides and 74% for amino acids), the phylogenetic tree topology revealed a distinct PCV2h clade including recombinant/intermediate strains and local vaccines. The Cap protein sequences from 11 PCV2d field strains had the 2d-genotype-typical motif 86SNPLSV91 in loop CD, the motif TGID in loop GH-HI, and the motif 230PLNPK234 in loop CT. The PCV2h isolates (and vaccines) had the 86SNPLSV91, SAID, and 230L(N/H)PK234 motifs. Selection pressure analysis indicated positive selection at seven sites: A68N in immunoreactive region (IRR)-A; 119G and 130V in IRR-B; and 167L, T190(A/S), 194D and 202F in IRR-C. We identified PCV2h as the genotype of the recombinant strains, which resulted from intergenotype recombination of PCV2a, PCV2b, and PCV2d. The current data provide new information about the diversity, distribution, and dominance of the PCV2 genotype in Vietnam.


Assuntos
Infecções por Circoviridae , Circovirus , Doenças dos Suínos , Vacinas , Animais , Povo Asiático , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/prevenção & controle , Infecções por Circoviridae/veterinária , Genótipo , Humanos , Filogenia , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/prevenção & controle , Vietnã/epidemiologia
3.
Antimicrob Agents Chemother ; 65(8): e0009521, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34031050

RESUMO

Chloroquine (CQ) is the first-line treatment for Plasmodium vivax malaria in most countries where malaria is endemic. Monitoring P. vivax CQ resistance (CQR) is critical but remains challenged by the difficulty to distinguish real treatment failure from reinfection or liver relapse. The therapeutic efficacy of CQ against uncomplicated P. vivax malaria was evaluated in Gia Lai Province, Vietnam. Sixty-seven patients were enrolled and followed for 42 days using microscopy and quantitative PCR. Adequate clinical and parasitological response (ACPR) was 100% (66/66) on day 28 but 75.4% (49/65) on day 42. Eighteen recurrences (27.7%) were detected, with a median time to recurrence of 42 days (interquartile range [IQR], 35 to 42) and blood CQ concentration of <100 ng/ml. Primary infections leading to recurrence occurred in younger individuals (median age for ACPR = 25 years [IQR, 20 to 28]; recurrences = 18 [16 to 21]; P = 0.002) had a longer parasite clearance time (PCT for ACPR = 47.5 h [IQR, 36.2 to 59.8 h]; recurrences = 54.2 [48.4 to 62.0]; P = 0.035) and higher pvcrt gene expression (median relative expression ratio for ACPR = 0.09 [IQR, 0.05 to 0.22]; recurrences = 0.20 [0.15 to 0.56]; P = 0.002), but showed no differences in ex vivo CQ sensitivity. Parasite genotyping by microsatellites, single nucleotide polymorphism (SNP) barcoding, and whole-genome sequencing (WGS) identified a majority of homologous recurrences, with 80% (8/10) showing >98% identity by descent to paired day 0 samples. This study shows that CQ remained largely efficacious to treat P. vivax in Gia Lai; i.e., recurrences occurred late (>day 28) and in the presence of low blood CQ concentrations. However, the combination of both WGS and gene expression analysis (pvcrt) data with clinical data (PCT) allowed us to identify potential emergence of low-grade CQR, which should be closely monitored. (This study has been registered at ClinicalTrials.gov under identifier NCT02610686.).


Assuntos
Antimaláricos , Malária Vivax , Adulto , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Cloroquina/uso terapêutico , Resistência a Medicamentos/genética , Humanos , Malária Vivax/tratamento farmacológico , Plasmodium vivax/genética , Recidiva , Adulto Jovem
4.
J Antimicrob Chemother ; 75(8): 2272-2281, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32437557

RESUMO

BACKGROUND: Artemisinin-based combination therapies (ACTs) have significantly contributed to reduce Plasmodium falciparum malaria burden in Vietnam, but their efficacy is challenged by treatment failure of dihydroartemisinin/piperaquine ACT in Southern provinces. OBJECTIVES: To assess the efficacy of dihydroartemisinin/piperaquine for uncomplicated P. falciparum malaria in Gia Lai, Central Vietnam, and determine parasite resistance to artemisinin (ClinicalTrials.gov identifier NCT02604966). METHODS: Sixty patients received either dihydroartemisinin/piperaquine (4 mg/kg/day, 3 days; n = 33) or artesunate monotherapy (4 mg/kg/day, 3 days; n = 27) followed by dihydroartemisinin/piperaquine (AS + DHA/PPQ). Clinical phenotypes were determined during a 42 day follow-up and analysed together with ex vivo susceptibility to antimalarials and molecular markers of drug resistance. RESULTS: Day 3 positivity rate was significantly higher in the AS + DHA/PPQ arm compared with dihydroartemisinin/piperaquine (70.4% versus 39.4%, P = 0.016). Parasite clearance time was 95.2 h (AS + DHA/PPQ) versus 71.9 h (dihydroartemisinin/piperaquine, P = 0.063) and parasite clearance half-life was 7.4 h (AS + DHA/PPQ) versus 7.0 h (dihydroartemisinin/piperaquine, P = 0.140). Adequate clinical and parasitological response at Day 42 was 100% in both arms. By RT-qPCR, 36% (19/53) patients remained positive until Day 7. No recurrences were detected. kelch13 artemisinin resistance mutations were found in 87% (39/45) of isolates and 50% (20/40) were KEL1/C580Y. The piperaquine resistance marker plasmepsin-2 was duplicated in 10.4% (5/48). Isolates from Day 3-positive patients (n = 18) had higher ex vivo survival rates to artemisinin compounds (P < 0.048) and prevalence of kelch13 mutations (P = 0.005) than Day 3-negative patients (n = 5). The WHO definition of artemisinin resistance was fulfilled in 60% (24/40) of cases. CONCLUSIONS: Although dihydroartemisinin/piperaquine remained effective to treat P. falciparum, the high Day 3 positivity rate and prevalence of KEL1 strains calls for continuous monitoring of dihydroartemisinin/piperaquine efficacy in Central Vietnam.


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Quinolinas , Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Artesunato , Humanos , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Plasmodium falciparum/genética , Quinolinas/uso terapêutico , Vietnã/epidemiologia
5.
Bioorg Med Chem Lett ; 25(2): 254-8, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25499882

RESUMO

Three new ent-kaurane diterpenoids, 7ß,16α,17-trihydroxy-ent-kauran-19-oic acid (1), 7ß,17-dihydroxy-16α-ent-kauran-19-oic acid 19-O-ß-d-glucopyranoside ester (2), 7ß,17-dihydroxy-ent-kaur-15-en-19-oic acid 19-O-ß-d-glucopyranoside ester (3) along with five known compounds, paniculoside IV (4), 16α,17-dihydroxy-ent-kaurane (5), 16ß,17-dihydroxy-ent-kaurane (6), 16ß,17-dihydroxy-ent-kauran-19-al (7), and 16ß,17-dihydroxy-ent-kauran-19-oic acid (8) were isolated from the fruits of Annona glabra. Their chemical structures were elucidated by physical and chemical methods. All compounds were evaluated for inhibitory activity against nitric oxide (NO) production in LPS-stimulated RAW 264.7 macrophages. As the results, compound 3 showed potent inhibitory LPS-stimulated NO production in RAW 264.7 macrophages with the IC50 value of 0.01±0.01µM; compounds 1 and 7 showed significant inhibitory NO production with the IC50 values of 0.39±0.12µM and 0.32±0.04µM, respectively.


Assuntos
Annona , Diterpenos do Tipo Caurano/farmacologia , Frutas , Macrófagos/efeitos dos fármacos , Óxido Nítrico/antagonistas & inibidores , Extratos Vegetais/farmacologia , Animais , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/isolamento & purificação , Lipopolissacarídeos/toxicidade , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/biossíntese , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
6.
Pharm Biol ; 53(11): 1602-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25856711

RESUMO

CONTEXT: Traditional Chinese medicines have attracted increasing interest as potential sources of novel drugs with a wide range of biological and pharmacological activities. Annona glabra Linn (Annonaceae) is used in traditional medicine as an anticancer drug. Phytochemical investigation of this plant led to the isolation of acetogenins, ent-kauranes, peptides, and alkaloids. In addition, compounds exhibited anticancer, anti-HIV-reserve, and antimalaria. OBJECTIVE: Isolation, structure determination, and cytotoxic activity evaluation of compounds from the methanol extract from A. glabra fruits. MATERIALS AND METHODS: Using chromatographic methods to isolate compounds from the A. glabra methanol extract. The cytotoxic activity of compounds was evaluated by a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. In addition, compounds which showed significant cytotoxic activity were chosen for further study apoptosis characteristics. RESULTS: One new, (2E,4E,1'R,3'S,5'R,6'S)-dihydrophaseic acid 1,3'-di-O-ß-d-glucopyranoside, and eight known compounds, (2E,4E,1'R,3'S,5'R,6'S)-dihydrophaseic acid 3'-O-ß-d-glucopyranoside (2), icariside D2 (3), icariside D2 6'-O-ß-d-xylopyranoside (4), 3,4-dimethoxyphenyl O-ß-d-glucopyranoside (5), 3,4-dihydroxybenzoic acid (6), blumenol A (7), cucumegastigmane I (8), and icariside B1 (9), were isolated from the fruits of A. glabra. Icariside D2 (3) was found to show significant cytotoxic activity on the HL-60 cell line with the IC50 value of 9.0 ± 1.0 µM and did not show cytotoxic activity on the Hel-299 normal cell line. The further test indicated that compound 3 induced apoptosis via alteration of expression of apoptosis-related proteins and decreased phosphorylation of AKT in HL-60 cells. DISCUSSION AND CONCLUSION: The results suggested that the constituents from A. glabra may contain effective compounds which can be used as anticancer agents.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Citotoxinas/química , Citotoxinas/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Annona , Antineoplásicos Fitogênicos/toxicidade , Proliferação de Células/efeitos dos fármacos , Citotoxinas/toxicidade , Frutas , Células HL-60 , Humanos , Extratos Vegetais/toxicidade
7.
PLoS One ; 19(4): e0299068, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635820

RESUMO

This prospective observational study aimed to assess the impact of behavioral therapy on dysphagia in patients with acute ischemic stroke undergoing nasogastric tube feeding. The study was conducted between June 2020 and May 2022 at the Neurological Center of Bach Mai Hospital, Vietnam, with a sample size of 230 patients divided into two groups: a normal and a behavioral therapy group. The normal therapy group received routine care and treatment based on standard protocols, while the behavioral therapy group underwent daily swallowing exercises for approximately 60 minutes. The Gugging Swallowing Screen (GUSS) was utilized to screen individuals with dysphagia, and the difference-in-differences (DID) method was adopted to estimate the effect of behavioral therapy on dysphagia patients. The study concluded that behavioral therapy improved dysphagia in patients with acute ischemic stroke undergoing nasogastric tube feeding. This study highlights the potential of behavioral therapy as an effective intervention for dysphagia rehabilitation in stroke patients.


Assuntos
Transtornos de Deglutição , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/terapia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Deglutição , Terapia Comportamental
8.
Front Immunol ; 15: 1364161, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38803504

RESUMO

Introduction: Atherosclerosis, a leading cause of global cardiovascular mortality, is characterized by chronic inflammation. Central to this process is the NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome, which significantly influences atherosclerotic progression. Recent research has identified that the olfactory receptor 2 (Olfr2) in vascular macrophages is instrumental in driving atherosclerosis through NLRP3- dependent IL-1 production. Methods: To investigate the effects of Corilagin, noted for its anti-inflammatory attributes, on atherosclerotic development and the Olfr2 signaling pathway, our study employed an atherosclerosis model in ApoE-/- mice, fed a high-fat, high-cholesterol diet, alongside cellular models in Ana-1 cells and mouse bone marrow-derived macrophages, stimulated with lipopolysaccharides and oxidized low-density lipoprotein. Results: The vivo and vitro experiments indicated that Corilagin could effectively reduce serum lipid levels, alleviate aortic pathological changes, and decrease intimal lipid deposition. Additionally, as results showed, Corilagin was able to cut down expressions of molecules associated with the Olfr2 signaling pathway. Discussion: Our findings indicated that Corilagin effectively inhibited NLRP3 inflammasome activation, consequently diminishing inflammation, macrophage polarization, and pyroptosis in the mouse aorta and cellular models via the Olfr2 pathway. This suggests a novel therapeutic mechanism of Corilagin in the treatment of atherosclerosis.


Assuntos
Aterosclerose , Glucosídeos , Taninos Hidrolisáveis , Inflamassomos , Macrófagos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Transdução de Sinais , Animais , Taninos Hidrolisáveis/farmacologia , Taninos Hidrolisáveis/uso terapêutico , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Camundongos , Transdução de Sinais/efeitos dos fármacos , Inflamassomos/metabolismo , Glucosídeos/farmacologia , Glucosídeos/uso terapêutico , Macrófagos/metabolismo , Macrófagos/imunologia , Macrófagos/efeitos dos fármacos , Masculino , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE
9.
Sci Rep ; 14(1): 19007, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152137

RESUMO

In this paper, we study the formation of optical bistability (OB) and optical multistability (OM) in a degenerate four-level atomic system by an external magnetic field that is excited by a probe laser field, a coupling laser field and a signal laser field. The coupling field can cause electromagnetically induced transparency (EIT) for the probe field in the atomic medium, while the signal field and/or external magnetic field can switch between single-EIT and two-EIT regimes. Based on these properties, OB and OM effects can be formed at two different frequency regions of the probe field (two channels). By adjusting the magnetic field or the intensity and the frequency of laser fields, the threshold intensity and the width of OB or OM can also be changed simply. The model can be useful for experimental observations and applications in modern photonic devices.

10.
J Microbiol Biotechnol ; 33(6): 797-805, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-36908274

RESUMO

Species belonging to the Vernonia (Asteraceae), the largest genus in the tribe Vernonieae (consisting of about 1,000 species), are widely used in food and medicine. These plants are rich sources of bioactive sesquiterpene lactones and steroid saponins, likely including many as yet undiscovered chemical components. A phytochemical investigation resulted in the separation of three new stigmastane-type steroidal saponins (1 - 3), designated as vernogratiosides A-C, from whole plants of V. gratiosa. Their structures were elucidated based on infrared spectroscopy (IR), one-dimensional (1D) and two-dimensional nuclear magnetic resonance (2D NMR), high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), and electronic circular dichroism analyses (ECD), as well as chemical reactivity. Molecular docking analysis of representative saponins with α-glucosidase inhibitory activity was performed. Additionally, the intended substances were tested for their ability to inhibit α-glucosidase activity in a laboratory setting. The results suggested that stigmastane-type steroidal saponins from V. gratiosa are promising candidate antidiabetic agents.


Assuntos
Saponinas , Vernonia , Vernonia/química , Saponinas/farmacologia , Saponinas/química , alfa-Glucosidases , Estrutura Molecular , Simulação de Acoplamento Molecular
11.
J Nat Med ; 77(4): 928-938, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37294499

RESUMO

Plants of the Schisandra genus are commonly used in folk medicinal remedies. Some Schisandra species and their lignans have been reported to improve muscle strength. In the present study, four new lignans, named schisacaulins A-D, together with three previously described compounds ananonin B, alismoxide, and pregomisin were isolated from the leaves of S. cauliflora. Their chemical structures were determined by extensive analyses of HR-ESI-MS, NMR, and ECD spectra. Schisacaulin D and alismoxide significantly stimulated skeletal muscle cell proliferation by increasing the number of fused myotubes and expression of myosin heavy chain (MyHC) which may be good candidates for the treatment of sarcopenia.


Assuntos
Lignanas , Schisandra , Schisandra/química , Lignanas/química , Folhas de Planta/química , Proliferação de Células , Músculo Esquelético
12.
Nat Prod Res ; 36(20): 5370-5375, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34039230

RESUMO

Two new iridoid glycosides link with phenylpropanoids, rehmanniosides G (1) and H (2) along with 11 known compounds, 6-O-(E)-caffeoylajugol (3), 6-O-(E)-feruloylajugol (4), verbasoside (5), jionoside C (6), acteoside (7), leucosceptoside A (8), brachynoside (9), jionoside B1 (10), jionoside A1 (11), isoacteoside (12) and isomartynoside (13) were isolated from the roots of Rehmannia glutinosa (Gaertn.) DC. Their chemical structures were elucidated on the basis of extensive spectroscopic methods, including 1D, 2D NMR and mass spectra. Compounds 7 - 11 showed significant inhibitory α-glucosidase with IC50 values ranging from 261.4 to 408.7 µM (acarbose, IC50 of 204.2 ± 19.9 µM).[Formula: see text].


Assuntos
Rehmannia , Acarbose , Glicosídeos/química , Glicosídeos/farmacologia , Glicosídeos Iridoides/química , Glicosídeos Iridoides/farmacologia , Espectroscopia de Ressonância Magnética , Rehmannia/química , alfa-Glucosidases
13.
Nat Prod Res ; 36(9): 2314-2320, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33930986

RESUMO

Chemical investigation of the roots of Codonopsis javanica resulted in isolation of 12 compounds, including one new polyacetylene, codojavanyol (1), one new phenolic glycoside, codobenzyloside (7), and 10 known compounds, (2E,8E)-9-(tetrahydro-2H-pyran-2-yl)nona-2,8-diene-4,6-diyl-1-ol (2), lobetyol (3), lobetyolin (4), lobetyolinin (5), cordifolioidyne B (6), benzyl-α-L-arabinopyranosyl (1-6)-ß-D-glucopyranoside (8), (Z)-8-ß-D-glucopyranosyloxycinnamic acid (9), syringin (10), syringaresinol (11), and tryptophan (12). Their structures were elucidated by 1 D and 2 D NMR and MS spectroscopic analyses in comparison with the data reported in the literature. The stereochemistry of the C-2' position of 1 was identified based on time-dependent density functional theory (TDDFT) electronic circular dichroism (ECD) calculation. Among the isolates, compounds 3-5 were shown to have weak cytotoxicity toward three human carcinoma cell lines, including lung (A549), liver (HepG2), and breast (MCF7), with the induction of 41.4 to 55.6% cell death at the concentration of 100 µM.


Assuntos
Codonopsis , Codonopsis/química , Glicosídeos/química , Humanos , Estrutura Molecular , Fenóis/análise , Raízes de Plantas/química , Polímero Poliacetilênico
14.
Nat Prod Res ; 36(9): 2349-2355, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33092429

RESUMO

Phytochemical investigation of the branches and leaves of Alchornea annamica led to isolation of ten secondary metabolites, including two new megastigmane glucosides alnamicosides A (1) and B (2). The structure elucidation was confirmed by 1 D and 2 D NMR, ECD as well as HR-QTOF-MS experiments. The megastigmane derivatives 1 - 3 exhibited inhibitory effects on LPS-induced NO production in RAW264.7 cells with IC50 values of 78.72 ± 1.90, 77.40 ± 9.40 and 82.16 ± 4.56 µM, respectively. This is the first report on chemical constituents and biological activity of the plant A. annamica.


Assuntos
Euphorbiaceae , Animais , Euphorbiaceae/química , Camundongos , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Folhas de Planta/química , Células RAW 264.7
15.
Nat Prod Res ; : 1-8, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36255129

RESUMO

Phytochemical study on the methanol extract of the stems and leaves of Kadsura induta led to the isolation of six dibenzocyclooctadiene lignans, including three new compounds named kadsindutalignans A-C (1-3), and three known ones, heteroclitalignan B (4), kadsuphilin C (5) and kadsulignan E (6). Their structures were elucidated based on extensive spectroscopic analyses, including HRESIMS, 1D- (1H NMR and 13C NMR), 2D-NMR (HSQC, HMBC, 1H-1H COSY and NOESY), and experimental circular dichroism (CD) spectra. All the isolates inhibited NO production in LPS-activated RAW264.7 cells with IC50 values in the range from 5.67 ± 0.54 µM to 38.19 ± 2.03 µM, compared to that of the positive control of NG-monomethyl-L-arginine acetate (L-NMMA) with an IC50 value of 8.90 ± 0.48 µM. Interestingly, the new compound 2 showed potential inhibition of NO production with an IC50 value of 5.67 ± 0.54 µM, which was higher than that of the positive control.

16.
Nat Prod Res ; 35(21): 3931-3938, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32237915

RESUMO

Three new pregnane glycosides, drevoluosides O-Q (1-3) along with five known volubiloside C (4), dreageoside A11 (5), 17ß-marsdenin (6), stavaroside H (7), and hoyacarnoside G (8) were isolated from the methanol extract of the Dregea volubilis leaves. Their structures were elucidated by chemical and spectroscopic methods. Compounds 6-8 showed significant anti α-glucosidase activity with the inhibitory percentages ranging from 32.6 to 47.1% at the concentration of 200 µM. Compound 3 showed significant inhibitory α-amylase activity with IC50 value of 51.3 ± 2.1 µM.


Assuntos
Inibidores de Glicosídeo Hidrolases , alfa-Glucosidases , Inibidores de Glicosídeo Hidrolases/farmacologia , Glicosídeos/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta , Pregnanos/farmacologia , alfa-Amilases
17.
Plants (Basel) ; 9(10)2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33053736

RESUMO

Anoectochilus roxburghii is a wild edible species and has been traditionally used for a wide range of diseases in many countries. Our research aims to find the optimal light-emitting diode (LED) lighting conditions to improve the growth and development of A. roxburghii seedling at the acclimation stage. Two-month-old explants were cultured under the various lighting conditions including red (R), blue (B), BR (one blue: four red), BRW151 (one blue: five red: one white), BRW142 (one blue: four red: two white), and fluorescent lamp (FL). The results showed that the lighting conditions not only affect the growth and morphology of plants but also the accumulation of total flavonoids. Single wavelengths (B or R LED) inhibited the growth and secondary biosynthesis of A. roxburghii, while the BR LED showed an enhancement in both growth and biomass accumulation. A. roxburghii plants were grown under BR LED light has average plant height (7.18 cm), stem diameter (17.6mm), number of leaves (5.78 leaves/tree), leaf area (4.67 cm2), fresh weight (0.459 g/tree), dry matter percentages (11.69%), and total flavonoid (1.811 mg/g FW) is considered to be superior to FL lamps and other LEDs in the experiment. This indicates that both blue and red wavelengths are required for the normal growth of A. roxburghii. To learn more about how light affects flavonoid biosynthesis, we evaluated the expression of genes involved in this process (pal, chs, chi, and fls) and found that BR LED light enhances the expression level of chi and fls genes compared to fluorescent lamps (1.18 and 1.21 times, respectively), leading to an increase in the flavonoid content of plant. Therefore, applying BR LED during in vitro propagation of A. roxburghii could be a feasible way to improve the medicinal value of this plant.

18.
BMJ Glob Health ; 5(4): e002166, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32337087

RESUMO

Development of a robust technical assistance system is an essential component of a sustainable HIV response. Vietnam's National HIV Program is transitioning from a largely donor-funded programme to one primarily supported by domestic resources. Telehealth interventions are increasingly being used for training, mentoring and expert consultation in high-resource settings and hold significant potential for use as a tool to build HIV health worker capacity in low and middle-income countries. We designed, implemented and scaled up a novel HIV telehealth programme for Vietnam, with the goal of building a sustainable training model to support the country's HIV workforce needs. Over a 4-year period, HIV telehealth programmes were initiated in 17 public institutions with participation of nearly 700 clinical sites across 62 of the 63 provinces in the country. The telehealth programme was used to deliver certificate training courses, provide clinical mentoring and case-based learning, support programme implementation, provide coaching in quality improvement and disseminate new guidelines and policies. Programme evaluation demonstrated improved health worker self-reported competence in HIV care and treatment and high satisfaction among the programme participants. Lessons learnt from Vietnam's experience with telehealth can inform country programmes looking to develop a sustainable approach to HIV technical assistance and health worker capacity building.


Assuntos
Infecções por HIV , Telemedicina , Infecções por HIV/epidemiologia , Infecções por HIV/terapia , Pessoal de Saúde , Humanos , Avaliação de Programas e Projetos de Saúde , Vietnã
19.
BMJ Open ; 9(5): e027076, 2019 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-31061047

RESUMO

OBJECTIVE: To provide the first ever published estimates of the price and expenditure elasticities of demand for beer and wine in Vietnam and thereby contribute to policy initiatives aimed at reducing the excessive consumption of alcohol. METHODS: We use a linear approximation of the Almost Ideal Demand System and data from the Vietnam Household Living Standards Survey for 2010, 2012 and 2014. RESULTS: We find that the demand for beer and wine in Vietnam is price and expenditure inelastic with average price elasticities of -0.283 and -0.317 and average expenditure elasticities of 0.401 and 0.156, respectively. That is, we find that beer and wine consumption decline whenever their respective prices increase and their consumption increases whenever expenditure rises. CONCLUSIONS: The results of the study lend confidence to calls for increased taxation of alcoholic products on public health grounds in Vietnam.


Assuntos
Cerveja/economia , Comércio/estatística & dados numéricos , Fatores Socioeconômicos , Impostos/estatística & dados numéricos , Vinho/economia , Adulto , Características da Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Vietnã
20.
Open Access Maced J Med Sci ; 7(24): 4292-4296, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-32215080

RESUMO

BACKGROUND: Dry eye (DE) can effect on quality of life by pain, inability to perform certain activities that require prolonged attention (driving, reading,…) and productivity at work and finally effect to Q0L associated with DE. OSDI is scale questionnaire is created team to measure the quality of life related to ocular surface disease. AIM: To describe the dry eye disease according to OSDI scale and related factors of this disease. METHODS: A cross-sectional descriptive study was carried out on outpatients (≥ 16-year-old) who were examined and diagnosed with dry eyes at Vietnam National Institute Of Ophthalmology from April to July 2018. Data was collected using the OSDI questionnaire. RESULTS: The average age of participants was 44.6 years; 80.9% of patients were female; 39.9% were identified having mild dry eye. The related factors have been identified that associated with severe dry eye, including age OR = 1.03 (95% CI: 1.01-1.05, p = 0.005), binocular good vision OR = 0.11 (95% CI: 0.05-0.23; p < 0.0001), medical history OR = 17.09 (95% CI: 2.24-130.25; p < 0.0001), chronic conjunctivitis OR = 0.36 (95% CI: 0.14-0.91; p = 0.027), refractive errors OR = 0.14 (95% CI: 0.04-0.48; p < 0.0001), Sjogren's syndrome OR = 31.13 (95% CI: 7.08-136.76; p < 0.0001). CONCLUSION: Several related factors have been identified associated with severe dry eye, including: age, binocular good vision, medical history, chronic conjunctivitis, refractive errors, Sjogren's syndrome.

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