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1.
Biomed Mater ; 19(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38215488

RESUMO

Heparin recently has been discovered as a novel anti-cancer agent. The combinations of heparin with other agents was reported not only to reduce the undesired effects of free heparin and increase the cellular uptake of the delivered molecules, but also is the basis for the design and development of multi-stimulation response systems to improve their killing cancer cell efficiency at the target positions. This study aimed to design a redox and pH dual-responsive anticancer system based on heparin for cisplatin (CPT) therapy. Heparin was first cross-linked with Poloxamer 407 chains via disulfide bridges to form a redox-sensitive system Hep-P407. CPT was then encapsulated into the Hep-P407 system via the complex of Platin and carboxyl groups to form the redox/pH-responsive system CPT@Hep-P407. The obtained Hep-P407 systems were proved and characterized using specific techniques including1H-NMR, zeta potential, Dynamic Light Scattering (DLS) and Fourier-transform infrared spectroscopy. The dual-responsive behavior to redox and pH of CPT@Hep-P407 was proved through DLS, zeta andin vitrorelease analysis meanwhile its cytotoxicity was investigated using Resazurin assay. The CPT@Hep-P407 system is expected to be a promising redox/pH-responsive anticancer system based on heparin for CPT therapy.


Assuntos
Cisplatino , Heparina , Polietilenoglicóis , Polietilenoimina , Nanogéis , Heparina/química , Oxirredução , Concentração de Íons de Hidrogênio , Sistemas de Liberação de Medicamentos/métodos
2.
ACS Omega ; 8(45): 42429-42439, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38024769

RESUMO

The fundamental goal of this research was to use an environmentally friendly sonochemical method to synthesize a Fe3O4/CuO/chitosan magnetic nanocomposite. The nanocomposites featured particle sizes ranging from 50 to 90 nm, and structural characteristics were thoroughly examined. Moreover, the material displayed selective photodegradation capabilities with MB, achieving an impressive efficiency of nearly 98% within 180 min under specific conditions. Notably, the material's reusability was remarkable, maintaining an efficiency of approximately 88% even after five cycles. The possible photodegradation mechanism was proposed based on the evaluation of energy bands, along with a comprehensive analysis of the impacts on MB photodegradation. Concurrently, adsorption isotherms and kinetic models were evaluated. Additionally, this material exhibited promising antibacterial activity against Saccharomyces cerevisiae, Bacillus subtilis, and Escherichia coli. These findings suggested that the Fe3O4/CuO/chitosan material could be utilized in real-world scenarios for environmental purification due to its ability to function as a photocatalyst and antibacterial agent.

3.
Phys Chem Chem Phys ; 25(41): 28296-28308, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37830378

RESUMO

NaGdF4 nanocrystalline doped with different concentrations of Eu3+ ions were synthesized using the precipitation method. The structure and morphology of the material were investigated through the measurements of the XRD patterns and SEM images, respectively. The optical properties of the NaGdF4:Eu3+ nanocrystalline were studied in the framework of the Judd-Ofelt theory in which the Ωλ parameters were calculated by two methods: the traditional method using the luminescence spectra and the self-referenced method using the luminescence excitation spectra. In NaGdF4:Eu3+ nanocrystalline, the Gd3+ ions in the lattice act as sensitizer centers for the luminescence of Eu3+ ions under excitation at 272 and 310 nm. The energy transfer process from Gd3+ to Eu3+ causes the emission enhancement of Eu3+ ions. Upon excitation by the characteristic wavelengths of Gd3+, the luminescence efficiency of the Eu3+ ions in NaGdF4:Eu3+ is affected by two mechanisms: the emission of Gd3+ ions and the trapping of excited energy by the Eu3+ ions. The energy transfer between Eu3+ ions was also discussed in detail. This process leads to the enhancement of the luminescence bands originating from the 5D0 level. The dominant interaction between the Eu3+ ions in the energy transfer process is the dipole-dipole mechanism, which is determined by fitting the decay curve of the 5D2 level to the Inokuti-Hirayama model.

4.
Environ Res ; 237(Pt 2): 117018, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37657605

RESUMO

Distribution patterns of 10 phthalic acid diesters (PAEs) and four cyclic volatile methylsiloxanes (cVMSs) were investigated in fine particulate matter (PM0.1 and PM0.5) collected from Bac Ninh, an industrial province in Vietnam during September-October in 2021. Total concentrations of PAEs found in PM0.1 and PM0.5 were in the ranges of 1.76-372 (median: 34.0 ng/m3) and 2.23-895 ng/m3 (median: 15.4 ng/m3), respectively. Among PAEs, di-n-butyl phthalate (DBP) was the most abundant compound found in PM0.1, whereas, di-2-(ethyl)hexyl phthalate (DEHP) was measured at the highest concentration in PM0.5. Total concentrations of cVMSs measured in PM0.1 and PM0.5 were in the ranges of method quantification limit (MQL)-203 (median: 2.10 ng/m3) and MQL-537 ng/m3 (median: 0.389 ng/m3), respectively. Among cVMSs, decamethylcyclopentasiloxane (D5) was found at the highest concentration in both PM0.1 and PM0.5 fractions of particulate matter. The concentration ratios between PAEs and cVMSs in PM0.1/PM0.5 were greater than 1 (except di-n-octyl phthalate: DnOP), suggesting that these chemicals tend to sorb to PM0.1 more preferentially than PM0.5. Among sampling locations, high concentrations of PAEs and cVMSs were found at traffic intersections (Que Vo district) and a craft village (Tu Son city). Relatively stronger correlations existed between cVMSs pairs in PM0.1 and PM0.5 (correlation coefficient: 0.73-1) than those of PAEs (-0.83-0.90). The human exposure doses to PAEs and cVMSs through inhalation of particulate matter were estimated based on the measured concentrations in PM0.1 and PM0.5 fractions. The estimated exposure doses of PAEs and cVMSs for infants (7.1 ng/kg-bw/d and 2.5 ng/kg-bw/d) were higher than those for adults (2.6 ng/kg-bw/d and 0.9 ng/kg-bw/d).

5.
Artigo em Inglês | MEDLINE | ID: mdl-35368752

RESUMO

Atopic dermatitis (AD) is a common inflammatory skin disease, which can be worsened under sleep deprivation (SD) conditions. This study investigated the efficacy and the mechanism of action of the traditional herbal formula Seungmagalgeun-tang (SMGGT) on the inflammation and behavioral changes in a mouse model of AD exposed to SD. SMGGT decreased levels of IgE, TNF-α, IL-4, IL-13, and mast cell infiltration and reduced the expression of CD3 in the mouse skin. SMGGT also reversed the SD-induced increase in corticosterone and decrease in melatonin level. Furthermore, SMGGT reduced the immobility time in the tail suspension test significantly. HaCaT cells and HMC-1 cells were used to investigate the effects of SMGGT on cell signaling pathways. In TNF-α/IFN-γ (TI) treated HaCaT cells, SMGGT reduced production of TARC/CCL17 and MDC/CCL22 and suppressed the p38 MAPK, STAT1, and NF-κB pathways. In substance P (SP)/CRH-stimulated HMC-1 cells, SMGGT decreased VEGF production and inhibited ERK phosphorylation. Network pharmacology and molecular docking analysis revealed that puerarin and paeoniflorin might contribute to the effects of SMGGT by targeting several AD-related molecules and pathways. Puerarin and paeoniflorin exerted anti-inflammatory effects by decreasing production of MDC/CCL22 and IL-6 in TI-treated HaCaT cells and VEGF production in SP/CRH-stimulated HMC-1 cells. This study suggests that SMGGT with puerarin and paeoniflorin as main bioactive components alleviates skin inflammation and depression-like behavior in a sleep-deprived mouse model of AD.

6.
Plants (Basel) ; 11(3)2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35161369

RESUMO

The phytochemical constituents from the roots of Millettia speciosa were investigated by chromatographic isolation, and their chemical structures were characterized using the MS and NMR spectroscopic methods. A total of 10 compounds, including six triterpenoids, two flavonoids, and two phenolic compounds, were identified from the roots of M. speciosa. Out of the isolated compounds, eight showed inhibitory effects on NO production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells, with IC50 values ranging from 43.9 to 449.5 µg/mL. Ursane-type triterpenes significantly suppressed NO production compared to the remaining compounds. In addition, these compounds also exhibited remarkable inhibitory effects on α-glucosidase. Among the tested compounds, 4, 5, and 10 exhibited excellent α-glucosidase inhibition, with IC50 values ranging from 1.1 to 2.2 µg/mL. Almost all of the test compounds showed little or no acetylcholinesterase inhibition, except for 5, which showed moderate anti-acetylcholinesterase activity in vitro. The molecular docking study of α-glucosidase inhibition by 3-5 and 10 was conducted to observe the interactions of these molecules with the enzyme. Compounds 4, 5, and 10 exhibited a better binding affinity toward the targeted receptor and the H-bond interactions located at the entrance of the enzyme active site pocket in comparison to those of 3 and the positive control acarbose. Our findings evidence the pharmacological potential of this species and suggest that the phytochemicals derived from the roots of M. speciosa may be promising lead molecules for further studies on the development of anti-inflammatory and anti-diabetes drugs.

7.
PLoS One ; 15(5): e0233119, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32437454

RESUMO

The present study investigated the internal consistency reliability, construct validity, and item response characteristics of a newly developed Vietnamese version of the Kessler 6 (K6) scale among hospital nurses in Hanoi, Vietnam. The K6 was translated into the Vietnamese language following a standard procedure. A survey was conducted of nurses in a large general hospital in Hanoi, Vietnam, using a questionnaire including the Vietnamese K6, other scales (DASS21, health-related QOL, self-rated health, and psychosocial work environment), and questions about demographic variables. Internal consistency reliability (Cronbach's alpha coefficient) was calculated. A confirmatory factor analysis was conducted. Eleven hypotheses were tested (as Pearson's correlations with the K6) to assess the scale's construct validity. Item response theory (IRT) analysis was conducted to identify the item response characteristics. The Cronbach's alpha coefficient was 0.864. The explanatory and confirmatory factor analyses indicated a one-factor structure. Most hypotheses tested for construct validity were supported. IRT analysis indicated that response categories were located in order according to severity. K6 provided reliable information regarding higher levels of psychological distress. The findings suggest that the Vietnamese version of the K6 is a reliable and valid instrument to measure psychological distress among hospital nurses in Vietnam.


Assuntos
Hospitais , Enfermeiras e Enfermeiros , Autorrelato , Inquéritos e Questionários , Tradução , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Vietnã
8.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20078030

RESUMO

ObjectivesHealth care system of many countries are facing a surging burden of COVID-19. Although Vietnam has successfully controlled the COVID-19 pandemic to date, there is a sign of initial community transmission. An estimate of possible scenarios to prepare health resources in the future is needed. We used modelling methods to estimate impacts of mitigation measures on the COVID-19 pandemic in Vietnam. MethodsSEIR model built in the COVIDSIM1.1 tool was adopted using available data for estimation. The herd immunization scenario was with no intervention implemented. Other scenarios consisted of isolation and social distancing at different levels (25%, 50%, 75% and 10%, 20%, 30%, respectively). Outcomes include epidemic apex, daily new and cumulative cases, deaths, hospitalized patients and ICU beds needed. ResultsBy April 8, 2020, there would be 465 infected cases with COVID-19 in Viet Nam, of those 50% were detected. Cumulatively, there would be 1,400 cases and 30 deaths by end of 2020, if 75% of cases was detected and isolated, and 30% of social distancing could be maintained. The most effective intervention scenario is the detection and isolation of 75% infected cases and reduction of 10% social contacts. This will require an expansion of testing capacity at health facilities and in the community, posing a challenge to identify high-risk groups to prioritized testing. ConclusionsIn a localized epidemic setting, the expansion of testing should be the key measure to control the epidemic. Social distancing plays a significant role to prevent further transmission to the community.

10.
Artigo em Vietnamês | WPRIM (Pacífico Ocidental) | ID: wpr-820

RESUMO

Background: Can Gio mangrove forest is bio-diversified area. There is few studies on medical arthropod in Can Gio mangrove forest until now. Objective: To study bio-diversified feature and identify species with disease transmitting role. Subject and Method: In 2007, medical arthropod surveys were conducted at 3 sites located in the natural conserve zone- Can Gio mangrove forest. A cross-sectional study was used. Results and Conclusions: A total of samples of 6178 individuals of medical arthropod belonging to 65 species have been collected, including 3 species of flea (Siphonaptera), 1 species of ticks (Ixodidae), 6 species of chiggers (Trombiculidae), 6 species of mites (Gamasoidea), 25 species of flies (Muscoidea) and 24 species of mosquitoes (Culicidae). They belong to 37 genus, 17 families, 3 orders (Siphonaptera, Acarina and Diptera), and 2 classes (Insecta and Arachnida). 20 species having epidemiological role were found in Can Gio mangrove forest. The rate of Anopheles epiroticus biting human at night indoor, outdoor and daytime indoor is rather high, especially at the end of dry season at centre of the forest.


Assuntos
Áreas Alagadas
11.
Artigo em Vietnamês | WPRIM (Pacífico Ocidental) | ID: wpr-804

RESUMO

Background: In the period 2006-2010, a investigation on medical arthropod has been conducted\r\n', u'Objective: 1) To determine species composition and distribution of medical arthropod. 2) To find species transmitted disease \r\n', u'Subject and method: The cross sectional, descriptive and analytic investigation was conducted in 3 communes along the Ho Chi Minh road in Cao Bang province. \r\n', u'Results and conclusion: : A total of 3.437 of samples of medical arthropod belonging to 96 species have been collected including: three species of flea (Siphonaptera), two species of tick (Ixodoidea), four species of chigges (Trombiculidae), ten species of mites (Gamasoidea), twenty four species of flies (Muscoidea), and fifty-three species of mosquito (Culicidae). They belong to 39 genuses, 17 families, 3 orders: (Siphonaptera, Acarina and Diptera); two classes (Insecta and Arachnida). \r\n', u'Some species having epidemiological role such as Aedes albopictus, Culex tritaeniorhyncus, Cx. quinquefasciatus, Cx. vishnui ... were predominant at all study sites. Anopheles minimus, the main malaria vector, was mainly collected in cattle- sheds in Truong Ha and Bach Dang communes. \r\n', u'

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