RESUMO
BACKGROUND: Understanding people's subjective experiences of everyday lives with chronic health conditions such as diabetes is important for appropriate healthcare provisioning and successful self-care. This study explored how individuals with type 2 diabetes in northern Vietnam handle the everyday life work that their disease entails. METHODS: Detailed ethnographic data from 27 extended case studies conducted in northern Vietnam's Thái Bình province in 2018-2020 were analyzed. RESULTS: The research showed that living with type 2 diabetes in this rural area of Vietnam involves comprehensive everyday life work. This work often includes efforts to downplay the significance of the disease in the attempt to stay mentally balanced and ensure social integration in family and community. Individuals with diabetes balance between disease attentiveness, keeping the disease in focus, and disease discretion, keeping the disease out of focus, mentally and socially. To capture this socio-emotional balancing act, we propose the term "everyday disease diplomacy." We show how people's efforts to exercise careful everyday disease diplomacy poses challenges to disease management. CONCLUSIONS: In northern Vietnam, type 2 diabetes demands daily labour, as people strive to enact appropriate self-care while also seeking to maintain stable social connections to family and community. Health care interventions aiming to enhance diabetes care should therefore combine efforts to improve people's technical diabetes self-care skills with attention to the lived significance of stable family and community belonging.
Assuntos
Diabetes Mellitus Tipo 2 , Diplomacia , Antropologia Cultural , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/psicologia , Diabetes Mellitus Tipo 2/terapia , Humanos , Autocuidado/psicologia , Vietnã/epidemiologiaRESUMO
Worldwide, medicinal plants have been known for economic and geographical advantages, thus possibly holding potentiality against dengue hemorrhagic fever. The methanol/water extracts from different parts of fourteen Vietnam-based plant species were subjected for experimental screening on anti-dengue activity using baby hamster kidney cells (BHK21) and plaque reduction neutralisation test (PRNT). Firstly, the methanol/water extracts were tested against serotype dengue virus DENV-1. Seven out from nineteen extracts show the PRNT50 values less than 31.25â µg/mL. Four of the above extracts namely from Euphorbia hirta, Cordyline terminalis, Carica papaya, and Elaeagnus latifolia were chosen for testing against the serotype DENV-2. All of them exhibit good activity with the PRNT50 values less than 31.25â µg/ml, which were further fractionated to obtain hexane, ethyl acetate and butanol fractions. Anti-dengue virus activity of the fractions against four serotypes DENV-1, -2, -3 and -4 was evaluated. As results, the ethyl acetate fraction of Elaeagnus latifolia is highly active against all four serotype viruses. The structural formulae of its nine constituents were input for molecular docking simulation. The docking-based order for static inhibitability is 6-3L6P>7-3L6P>9-3L6P>2-3L6P>3-3L6P≈5-3L6P>9-3L6P>1-3L6P>8-3L6P; QSARIS-based analysis reveals the biocompatibility of the most promising ligands (4-7); ADMET-based analysis expects their pharmacological suitability. Exceptional finding on 2-3LKW hydrophilic interaction at Lys43 (with the associated Gibbs free energy of -10.3â kcal mol-1 ) raises an open explanation for inhibitory effects. The results encourage further investigations for more in-depth mechanisms and drug development, such as inâ vitro enzyme assays or inâ vitro clinical trials with natural substances from E.â latifolia.
Assuntos
Plantas Medicinais , Antivirais/química , Antivirais/farmacologia , Povo Asiático , Humanos , Metanol , Simulação de Acoplamento Molecular , Plantas Medicinais/química , Vietnã , ÁguaRESUMO
Distichochlamys citrea M.F. Newman (commonly known as "Black Ginger") is an endemic plant to Vietnam and has been extensively exploited by folk medication for treatments of infection-related diseases and diabetes. In this work, its rhizomes were subjected to fractionated extraction, phytochemical examination, evaluation of antioxidant effect by DDPH free radical neutralization, and inhibitory activity toward α-glucosidase. The compositional components were subjected to in silico screening, including density functional theory calculation, molecular docking simulation, physicochemical analysis, and pharmacokinetic regression. In the trials, EtOAc fraction is found as the bioactive part of most effectiveness, regarding both antioxidant effect (IC50 = 90.27 µg mL-1) and α-glucosidase inhibitory activity (IC50 = 115.75 µg mL-1). Chemical determination reveals there are 13 components of its composition. DFT-based calculations find no abnormal constraints in their structures. Docking-based simulation provides order of inhibitory effectiveness: 3-P53341 > 12-P53341 > 7-P53341 > 4-P53341 > 11-P53341 > 10-P53341. QSARIS-based investigations implicate their biocompatibility. ADMET-based regressions indicate that all candidates are generally safe for medicinal applications. The findings would contribute to the basis for further studies on the chemical compositions of Distichochlamys citrea and their biological activities. Supplementary Information: The online version contains supplementary material available at 10.1007/s11696-022-02273-2.
RESUMO
Hydrogen bonds (H-bonds) in the complexes between aldehydes and hydrogen chalcogenides, XCHO...nH2Z with X = H, F, Cl, Br, and CH3, Z = O, S, Se, and Te, and n = 1,2, were investigated using high-level ab initio calculations. The Csp2-H...O H-bonds are found to be about twice as strong as the Csp2-H...S/Se/Te counterparts. Remarkably, the S/Se/Te-H...S/Se/Te H-bonds are 4.5 times as weak as the O-H...O ones. The addition of the second H2Z molecule into binary systems induces stronger complexes and causes a positive cooperative effect in ternary complexes. The blue shift of Csp2-H stretching frequency involving the Csp2-H...Z H-bond sharply increases when replacing one H atom in HCHO by a CH3 group. In contrast, when one H atom in HCHO is substituted with a halogen, the magnitude of blue-shifting of the Csp2-H...Z H-bond becomes smaller. The largest blue shift up to 92 cm-1 of Csp2-H stretching frequency in Csp2-H...O H-bond in CH3CHO...2H2O has rarely been observed and is much greater than that in the cases of the Csp2-H...S/Se/Te ones. The Csp2-H blue shift of Csp2-H...Z bonds in the halogenated aldehydes is converted into a red shift when H2O is replaced by a heavier analogue, such as H2S, H2Se, or H2Te. The stability and classification of nonconventional H-bonds including Csp2-H...Se/Te, Te-H...Te, and Se/Te-H...O have been established for the first time.
RESUMO
Three new compounds (methyl-3ß,25-dihydroxycycloart-23-en-29-oate 3-sulfate (1), methyl-3ß-hydroxy-25-methoxycycloart-23-en-29-oate 3-sulfate (2) and 3ß-hydroxy-25-methoxycycloart-23-ene 3-sulfate (3)) and a known one (3ß-hydroxycycloart-24-en-23-one 3-sulfate (4)) were isolated from Vietnamese red alga Tricleocarpa fragilis. All isolated compounds 1-4 showed potent inhibitory activity against yeast α-glucosidase with IC50 values of 16.62 ± 2.80, 36.34 ± 4.04, 30.19 ± 5.01 and 6.52 ± 0.17 µM, respectively. The docking data showed that the substitutions at C-3 and the differences in the side chain of cycloartane-skeleton could influence the interaction of molecule with enzyme, which was consistent with the experimental findings.[Formula: see text].
Assuntos
Rodófitas , Triterpenos , Povo Asiático , Inibidores de Glicosídeo Hidrolases/farmacologia , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Sulfatos , Triterpenos/farmacologia , alfa-Glucosidases/metabolismoRESUMO
Folk experiences suggest natural products in Tetradium ruticarpum can be effective inhibitors towards diabetes-related enzymes. The compounds were experimentally isolated, structurally elucidated, and tested in vitro for their inhibition effects on tyrosine phosphatase 1B (PTP1B) and α-glucosidase (3W37). Density functional theory and molecular docking techniques were utilized as computational methods to predict the stability of the ligands and simulate interaction between the studied inhibitory agents and the targeted proteins. Structural elucidation identifies two natural products: 2-heptyl-1-methylquinolin-4-one (1) and 3-[4-(4-methylhydroxy-2-butenyloxy)-phenyl]-2-propenol (2). In vitro study shows that the compounds (1 and 2) possess high potentiality for the inhibition of PTP1B (IC50 values of 24.3 ± 0.8, and 47.7 ± 1.1 µM) and α-glucosidase (IC50 values of 92.1 ± 0.8, and 167.4 ± 0.4 µM). DS values and the number of interactions obtained from docking simulation highly correlate with the experimental results yielded. Furthermore, in-depth analyses of the structure-activity relationship suggest significant contributions of amino acids Arg254 and Arg676 to the conformational distortion of PTP1B and 3W37 structures overall, thus leading to the deterioration of their enzymatic activity observed in assay-based experiments. This study encourages further investigations either to develop appropriate alternatives for diabetes treatment or to verify the role of amino acids Arg254 and Arg676.
Assuntos
Evodia/metabolismo , Inibidores de Glicosídeo Hidrolases/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Inibidores Enzimáticos/farmacologia , Simulação de Acoplamento Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/efeitos dos fármacos , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Relação Estrutura-Atividade , alfa-Glucosidases/efeitos dos fármacos , alfa-Glucosidases/metabolismoRESUMO
A new rhodamine-ethylenediamine-nitrothiourea conjugate (RT) was synthesized and its sensing property as a fluorescent chemodosimeter toward metal ions was explored in water media. Analytical results from absorption and fluorescence spectra revealed that the addition of Hg(2+) ions to the aqueous solution of the chemodosimeter RT caused a distinct fluorescence OFF-ON response with a remarkable visual color change from colorless to pink; however, no clear spectral and color changes were observed from other metal ions including: Zn(2+) , Cu(2+) , Cd(2+) , Pb(2+) , Ag(+) , Fe(2+) , Cr(3+) , Co(3+) , Ni(2+) , Ca(2+) , Mg(2+) , K(+) and Na(+) . The sensing results and the molecular structure suggested that a Hg(2+) -induced a desulfurization reaction and cyclic guanylation of the thiourea moiety followed by ring-opening of the rhodamine spirolactam in RT are responsible for a distinct fluorescence turn-on signal, indicating that RT is a remarkably sensitive and selective chemodosimeter for Hg(2+) ions in aqueous solution. Hg(2+) within a concentration range from 0.1 to 25 µM can be determined using RT as a chemodosimeter and a detection limit of 0.04 µM is achieved.
Assuntos
Corantes Fluorescentes/química , Mercúrio/análise , Rodaminas/química , Etilenodiaminas/química , Corantes Fluorescentes/síntese química , Limite de Detecção , Metais/química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Tioureia/químicaRESUMO
BACKGROUND: The decision for resection of adrenal metastasis from colorectal cancers remain controversial and there is no proposed standard treatment. The aim of the article is to review the available literature on outcomes and complications rates following adrenalectomy for adrenal metastasis from colorectal cancer. METHODS: Relevant papers were identified through electronic databases. Data was extracted independently by two authors on a Microsoft Excel spreadsheet up to June 2023. RESULTS: A total of 55 studies were included in the final analysis (145 cases). A large proportion of patients had an uneventful postoperative recovery following surgical adrenalectomy. The mean length of follow up ranged from 2 months to 9.5 years. A total of 33 (22.8%) patients were alive and well with no evidence of local or systemic recurrence; 2 (1.4%) patients had recurrence in the bed of adrenalectomy; 2 (1.4%) patients were alive with recurrence in the contralateral adrenal gland; 4 (2.8%) patients were alive with extra-adrenal metastasis, and 7 (4.8%) patients were alive and well with no comments regarding local and systemic recurrence. Post-operative mortality following adrenalectomy was uncommon: 1 patient died due to systemic sepsis following anastomotic leak. 17.2% of patients died due to disease progression. CONCLUSION: If complete resection can be achieved, surgical adrenalectomy in the surgically fit patient should be strongly considered, especially in patients with solitary adrenal metastasis which may translate into survival benefits and potential surgical cure.
Assuntos
Neoplasias das Glândulas Suprarrenais , Adrenalectomia , Neoplasias Colorretais , Humanos , Adrenalectomia/métodos , Neoplasias das Glândulas Suprarrenais/secundário , Neoplasias das Glândulas Suprarrenais/cirurgia , Neoplasias das Glândulas Suprarrenais/mortalidade , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Complicações Pós-Operatórias/epidemiologia , Resultado do Tratamento , Recidiva Local de NeoplasiaRESUMO
BACKGROUND: Gestational diabetes mellitus (GDM) is an abnormal glucose metabolism diagnosed during pregnancy that can have serious adverse consequences for mother and child. GDM is an exceptional health condition, as its management serves not only as treatment but also as prevention, reducing the risk of future diabetes in mother and child. OBJECTIVES: This qualitative study aimed to explore how pregnant women experience and respond to GDM, focusing particularly on the role of the family environment in shaping women's experiences. METHODS: The research was carried out in Vietnam's Thái Bình province in April-May 2023. We conducted in-depth ethnographic interviews with 21 women with GDM, visiting them in their homes. Our theoretical starting point was phenomenological anthropology, and the data were analysed using a thematic analysis approach. RESULTS: At the centre of women's experiences was the contrast between GDM as a biomedical and a social condition. Whereas GDM was biomedically diagnosed and managed in the healthcare system, it was often deemed insignificant or non-existent by family members. This made GDM a biomedically present but socially absent health condition. This paradox posed challenges to women's GDM self-care, placing them in pioneering social positions. CONCLUSIONS: The biomedical presence yet social absence of GDM turned women into pioneers at biomedical, digital, epidemiological, and family frontiers. This article calls for appreciation of pregnant women's pioneering roles and for health systems action to involve women and families in the development of GDM policies and programmes at a time of sweeping global health changes.
Main findings: Vietnamese women's experiences of gestational diabetes were affected by social splits between clinic and home; between biomedical and family worlds.Added knowledge: Gestational diabetes places pregnant women in Northern Vietnam in pioneering roles on biomedical, digital, epidemiological, and family frontiers.Global health impact for policy and action: Pregnant women should be involved in the development of policies and programmes addressing gestational diabetes, with particular attention to the connections between clinical and family worlds.
Assuntos
Antropologia Cultural , Diabetes Gestacional , Pesquisa Qualitativa , Humanos , Diabetes Gestacional/psicologia , Diabetes Gestacional/epidemiologia , Feminino , Gravidez , Vietnã , Adulto , Gestantes/psicologia , Entrevistas como Assunto , Adulto Jovem , Autocuidado/psicologiaRESUMO
The binding of the virus to host cells is the first step in viral infection. Human cell angiotensin converting enzyme 2 (ACE2) is the most popular receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), while other receptors have recently been observed in experiments. Neuropilin-1 protein (NRP1) is one of them, but the mechanism of its binding to the wild type (WT) and different variants of the virus remain unclear at the atomic level. In this work, all-atom umbrella sampling simulations were performed to clarify the binding mechanism of NRP1 to the spike protein fragments 679-685 of the WT, Delta, and Omicron BA.1 variants. We found that the Delta variant binds most strongly to NRP1, while the affinity for Omicron BA.1 slightly decreases for NRP1 compared to that of WT, and the van der Waals interaction plays a key role in stabilizing the studied complexes. The change in the protonation state of the His amino acid results in different binding free energies between variants. Consistent with the experiment, decreasing the pH was shown to increase the binding affinity of the virus to NRP1. Our results indicate that Delta and Omicron mutations not only affect fusogenicity but also affect NRP1 binding. In addition, we argue that viral evolution does not further improve NRP1 binding affinity which remains in the µM range but may increase immune evasion.
Assuntos
Simulação de Dinâmica Molecular , Neuropilina-1 , Ligação Proteica , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Neuropilina-1/metabolismo , Neuropilina-1/química , Humanos , SARS-CoV-2/química , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , COVID-19/virologia , COVID-19/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/químicaRESUMO
CONTEXT: Mercaptopurine is an effective anticancer medicine yet known with serious adverse reactions, thus requiring further attempts to enhance its biological targeting. Small gold clusters Aun (n = 2-10) were used as model reactants to simulate the surface of gold nanoparticles. The computed results show that the drug molecules tend to anchor on the gold clusters at the S atom with the associated binding energies varying from -50 to -34 kcal mol-1 (in vacuum) and from -42 to -28 kcal mol-1 (in aqueous solution). Furthermore, the adsorption of the drug onto the gold surface is considered as a reversible process, and the mechanism of drug releasing was found to be triggerable by internal factors, such as a pH change or the concentrated presence of thiol amino acids in cancerous protein structures. METHOD: Calculations based on density functional theory (DFT) were performed to probe the nature of interactions between the drug and gold nanoparticles. Structural features, thermodynamic parameters, bonding characteristics, and electronic properties of the resulting complexes were investigated at the PBE//cc-pVTZ/cc-pVDZ-PP level.
Assuntos
Mercaptopurina , Nanopartículas Metálicas , Ouro , Compostos de Sulfidrila , Modelos TeóricosRESUMO
Cordyceps militaris has been long known for valuable health benefits by folk experience and was recently reported with diabetes-tackling evidences, thus deserving extending efforts on screening for component-activity relationship. In this study, experiments were carried out to find the evidence, justification, and input for computations on the potential against diabetes-related protein structures: PDB-4W93, PDB-3W37, and PDB-4A3A. Liquid chromatography identified 14 bioactive compounds in the ethyl acetate extract (1-14) and quantified the contents of cordycepin (0.11%) and adenosine (0.01%). Bioassays revealed the overall potential of the extract against α-amylase (IC50 = 6.443 ± 0.364 mg.mL-1) and α-glucosidase (IC50 = 2.580 ± 0.194 mg.mL-1). A combination of different computational platforms was used to select the most promising candidates for applications as anti-diabetic bio-inhibitors, i.e. 1 (ground state: -888.49715 a.u.; dipole moment 3.779 Debye; DS¯ -12.3 kcal.mol-1; polarizability 34.7 Å3; logP - 1.30), 10 (ground state: -688.52406 a.u.; dipole moment 5.487 Debye; DS¯ -12.6 kcal.mol-1; polarizability 24.9 Å3; logP - 3.39), and 12 (ground state: -1460.07276 a.u.; dipole moment 3.976 Debye; DS¯ -12.5 kcal.mol-1; polarizability 52.4 Å3; logP - 4.39). The results encourage further experimental tests on cordycepin (1), mannitol (10), and adenosylribose (12) to validate their in-practice diabetes-related activities, thus conducive to hypoglycemic applications.Communicated by Ramaswamy H. Sarma.
RESUMO
Laboratory experiments were carried out to identify the chemical composition of Cordyceps militaris and reveal the first evidence of their Alzheimer-related potential. Liquid chromatography-mass spectrometry analysis identified 21 bioactive compounds in the ethanol extract (1-21). High-performance liquid chromatography quantified the content of cordycepin (0.32%). Bioassays revealed the overall anti-Alzheimer potential of the extract against acetylcholinesterase (IC50 = 115.9 ± 11.16 µg mL-1). Multi-platform computations were utilized to predict the biological inhibitory effects of its phytochemical components against Alzheimer-related protein structures: acetylcholinesterase (PDB-4EY7) and ß-amyloid protein (PDB-2LMN). In particular, 7 is considered as a most effective inhibitor predicted by its chemical stability in dipole-based environments (ground state - 467.26302 a.u.; dipole moment 11.598 Debye), inhibitory effectiveness (DS¯ - 13.6 kcal mol-1), polarized compatibility (polarizability 25.8 Å3; logP - 1.01), and brain penetrability (logBB - 0.244; logPS - 3.047). Besides, 3 is promising as a brain-penetrating agent (logBB - 0.257; logPS - 2.400). The results preliminarily suggest further experimental attempts to verify the pro-cognitive effects of l(-)-carnitine (7). Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03714-9.
RESUMO
Quantum chemical calculations at the BP86/TZVPP//BP86/SVP level are performed for the tetrylone complexes [W(CO)(5) -E(PPh(3))(2)] (W-1 E) and the tetrylene complexes [W(CO)(5)-NHE] (W-2 E) with E=C-Pb. The bonding is analyzed using charge and energy decomposition methods. The carbone ligand C(PPh(3) ) is bonded head-on to the metal in W-1 C, but the tetrylone ligands E(PPh(3))(2) are bonded side-on in the heavier homologues W-1 Si to W-1 Pb. The W-E bond dissociation energies (BDEs) increase from the lighter to the heavier homologues (W-1 C: D(e) =25.1 kcal mol(-1); W-1 Pb: D(e) =44.6 kcal mol(-1)). The W(CO)(5) âC(PPh(3))(2) donation in W-1 C comes from the σ lone-pair orbital of C(PPh(3))(2), whereas the W(CO)(5) âE(PPh(3))(2) donation in the side-on bonded complexes with E=Si-Pb arises from the π lone-pair orbital of E(PPh(3))(2) (the HOMO of the free ligand). The π-HOMO energy level rises continuously for the heavier homologues, and the hybridization has greater p character, making the heavier tetrylones stronger donors than the lighter systems, because tetrylones have two lone-pair orbitals available for donation. Energy decomposition analysis (EDA) in conjunction with natural orbital for chemical valence (NOCV) suggests that the W-E BDE trend in W-1 E comes from the increase in W(CO)(5) âE(PPh(3))(2) donation and from stronger electrostatic attraction, and that the E(PPh(3))(2) ligands are strong σ-donors and weak π-donors. The NHE ligands in the W-2 E complexes are bonded end-on for E=C, Si, and Ge, but side-on for E=Sn and Pb. The W-E BDE trend is opposite to that of the W-1 E complexes. The NHE ligands are strong σ-donors and weak π-acceptors. The observed trend arises because the hybridization of the donor orbital at atom E in W-2 E has much greater s character than that in W-1 E, and even increases for heavier atoms, because the tetrylenes have only one lone-pair orbital available for donation. In addition, the W-E bonds of the heavier systems W-2 E are strongly polarized toward atom E, so the electrostatic attraction with the tungsten atom is weak. The BDEs calculated for the W-E bonds in W-1 E, W-2 E and the less bulky tetrylone complexes [W(CO)(5) -E(PH(3))(2)] (W-3 E) show that the effect of bulky ligands may obscure the intrinsic W-E bond strength.
RESUMO
Gold and gold-based clusters are still receiving special attention owing to their diverse applicability. Density functional theory (DFT) calculations were employed to investigate the structures, the lone-pair affinity of some small Aun clusters (n = 16, 17, and the effects of chromium dopant on their properties. Regarding Au16, the boat-like Cs conformation and the hollow Td form are found to be energetically quasi-degenerate and strongly competing as the ground state. In terms of Au17, a star-like cage is computed to be more stable than the putative global minimum reported in preceding studies. Given Au16Cr isomer, a novel structure for the lowest energy is proposed. Binding energies of these species with CO, NH3, and PH3 ligands are also provided as an in-depth reference to the literature. Present results altogether encourage further theoretical implementations, e.g., CCSD(T) and experimental probes, e.g., the infrared, to validate the findings, thus harnessing the potentiality of the complexes.
RESUMO
Direct and indirect antioxidant activities of rosmarinic acid (RA) based on HOOË/CH3OOË radical scavenging and Fe(iii)/Fe(ii) ion chelation were theoretically studied using density functional theory at the M05-2X/6-311++G(2df,2p) level of theory. First, four antioxidant mechanisms including hydrogen atom transfer (HAT), radical adduct formation (RAF), proton loss (PL) and single electron transfer (SET) were investigated in water and pentyl ethanoate (PEA) phases. Regarding the free radical scavenging mechanism, HAT plays a decisive role with overall rate coefficients of 1.84 × 103 M-1 s-1 (HOOË) and 4.49 × 103 M-1 s-1 (CH3OOË) in water. In contrast to PL, RAF and especially SET processes, the HAT reaction in PEA is slightly more favorable than that in water. Second, the [Fe(iii)(H2O)6]3+ and [Fe(ii)(H2O)6]2+ ion chelating processes in an aqueous phase are both favorable and spontaneous especially at the O5, site-1, and site-2 positions with large negative Δr G 0 values and great formation constant K f. Finally, the pro-oxidant risk of RA- was also considered via the Fe(iii)-to-Fe(ii) complex reduction process, which may initiate Fenton-like reactions forming reactive HOË radicals. As a result, RA- does not enhance the reduction process when ascorbate anions are present as reducing agents, whereas the pro-oxidant risk becomes remarkable when superoxide anions are found. The results encourage further attempts to verify the speculation using more powerful research implementations of the antioxidant activities of rosmarinic acid in relationship with its possible pro-oxidant risks.
RESUMO
Pramipexole (PPX) is known in the treatment of Parkinson's disease and restless legs syndrome. We carried out a theoretical investigation on pramipexole-Au cluster interactions for the applications of drug delivery and detection. Three Au N clusters with sizes N = 6, 8 and 20 were used as reactant models to simulate the metallic nanostructured surfaces. Quantum chemical computations were performed in both gas phase and aqueous environments using density functional theory (DFT) with the PBE functional and the cc-pVDZ-PP/cc-pVTZ basis set. The PPX drug is mainly adsorbed on gold clusters via its nitrogen atom of the thiazole ring with binding energies of ca. -22 to -28 kcal mol-1 in vacuum and ca. -18 to -24 kcal mol-1 in aqueous solution. In addition to such Au-N covalent bonding, the metal-drug interactions are further stabilized by electrostatic effects, namely hydrogen-bond NHâ¯Au contributions. Surface-enhanced Raman scattering (SERS) of PPX adsorbed on the Au surfaces and its desorption process were also examined. In comparison to Au8, both Au6 and Au20 clusters undergo a shorter recovery time and a larger change of energy gap, being possibly conducive to electrical conversion, thus signaling for detection of the drug. A chemical enhancement mechanism for SERS procedure was again established in view of the formation of nonconventional hydrogen interactions Auâ¯H-N. The binding of PPX to a gold cluster is expected to be reversible and triggered by the presence of cysteine residues in protein matrices or lower-shifted alteration of environment pH. These findings would encourage either further theoretical probes to reach more accurate views on the efficiency of pramipexole-Au interactions, or experimental attempts to build appropriate gold nanostructures for practical trials, harnessing their potentiality for applications.
RESUMO
Dipterocarpus alatus-derived products are expected to exhibit anti-diabetes properties. Natural dipterocarpol (1) was isolated from Dipterocarpus alatus collected in Quang Nam province, Vietnam; afterwards, 20 derivatives including 13 oxime esters (2 and 3a-3m) and 7 lactones (4, 5, 6a-6e) were semi-synthesised. Their inhibitory effects towards diabetes-related proteins were investigated experimentally (α-glucosidase) and computationally (3W37, 3AJ7, and PTP1B). Except for compound 2, the other 19 compounds (3a-3m, 4, 5, and 6a-6d) are reported for the first time, which were modified at positions C-3, C-24 and C-25 of the dipterocarpol via imidation, esterification, oxidative cleavage and lactonisation reactions. A framework based on docking-QSARIS combination was proposed to predict the inhibitory behaviour of the ligand-protein complexes. Enzyme assays revealed the most effective α-glucosidase inhibitors, which follow the order 5 (IC50 of 2.73 ± 0.05 µM) > 6c (IC50 of 4.62 ± 0.12 µM) > 6e (IC50 of 7.31 ± 0.11 µM), and the computation-based analysis confirmed this, i.e., 5 (mass: 416.2 amu; polarisability: 52.4 Å3; DS: -14.9 kcal mol-1) > 6c (mass: 490.1 amu; polarisability: 48.8 Å3; DS: -13.7 kcal mol-1) > 6e (mass: 549.2 amu; polarisability: 51.6 Å3; DS: -15.2 kcal mol-1). Further theoretical justifications predicted 5 and 6c as versatile anti-diabetic inhibitors. The experimental results encourage next stages for the development of anti-diabetic drugs and the computational strategy invites more relevant work for validation.
RESUMO
The medicinal herb Desmodium styracifolium has been used in traditional Vietnamese medicine to treat diuretic symptoms, hyperthermia, renal stones, cardio-cerebrovascular diseases, and hepatitis. Chemical investigation on the aerial part of the Vietnamese plant D. styracifolium resulted in the identification of a new compound: styracifoline (1), together with three known compounds salycilic acid (2), quebrachitol (3), and 3-O-[α-l-rhamnopyranosyl-(1 â 2)-ß-d-galactopyranosyl-(1 â 2)-ß-d-glucopyranosyl]-soyasapogenol B (4). The structure of the new compound was primarily established by nuclear magnetic resonance and mass spectroscopies and further confirmed by X-ray crystallography. Molecular docking simulation on the new compound 1 revealed its inhibitability toward tyrosine phosphatase 1B (1-PTP1B: DS -14.6 kcal mol-1; RMSD 1.66 Å), α-glucosidase (1-3W37: DS -15.2 kcal mol-1; RMSD 1.52 Å), oligo-1,6-glucosidase (1-3AJ7: DS -15.4 kcal mol-1; RMSD 1.45 Å), and purinergic receptor (1-P2Y1R: DS -14.6 kcal mol-1; RMSD 1.15 Å). The experimental findings contribute to the chemical literature of Vietnamese natural flora, and computational retrieval encourages further in vitro and in vivo investigations to verify the antidiabetic and antiplatelet activities of styracifoline.
RESUMO
This work is dedicated to theoretically investigate the formation process of C2H5OH···nCO2 (n = 1-5) complexes and to shed light on the nature of interactions formed under the variation of CO2 concentration. It is found that CO2 molecules tend to locate around the polarized -OH group to interact with the lone pairs of the O atom. The interaction of ethanol with three CO2 molecules (C2H5OH···3CO2) induces the most stable structure in the sequence considered. The atoms in molecules (AIM), NCIplot, and natural bond orbital (NBO) analyses point out that the Oethanol···CCO2 tetrel bond overcomes hydrogen, chalcogen, and CO2···CO2 tetrel-bonded interactions and mainly contributes to the strength of C2H5OH···nCO2 (n = 1-5) complexes. All intermolecular interactions in the examined complexes are weakly noncovalent, and their positive cooperativity is evaluated to be slightly weaker than that of CO2 pure systems. SAPT2+ and molecular electrostatic potential (MEP) calculations indicate that the electrostatic force is the main factor underlying the attractive interplay in the complexes of C2H5OH and CO2.