Biocompatible chitosan-functionalized upconverting nanocomposites

Simultaneous integration of photon emission and biocompatibility into nanoparticles is an interesting strategy to develop applications of advanced optical materials. In this work, we present the synthesis of biocompatible optical nanocomposites from the combination of near-infrared luminescent lanthanide nanoparticles and water-soluble chitosan. NaYF4:Yb,Er upconverting nanocrystal guests and water-soluble chitosan hosts are prepared and integrated together into biofunctional optical composites. The control of aqueous dissolution, gelation, assembly, and drying of NaYF4:Yb,Er nanocolloids and chitosan liquids allowed us to design novel optical structures of spongelike aerogels and beadlike microspheres. Well-defined shape and near-infrared response lead upconverting nanocrystals to serve as photon converters to couple with plasmonic gold (Au) nanoparticles. Biocompatible chitosan-stabilized Au/NaYF4:Yb,Er nanocomposites are prepared to show their potential use in biomedicine as we find them exhibiting a half-maximal effective concentration (EC50) of 0.58 mg mL–1 for chitosan-stabilized Au/NaYF4:Yb,Er nanorods versus 0.24 mg mL–1 for chitosan-stabilized NaYF4:Yb,Er after 24 h. As a result of their low cytotoxicity and upconverting response, these novel materials hold promise to be interesting for biomedicine, analytical sensing, and other applications

20-Hydroxyecdysone from Dacrycarpus imbricatus bark inhibits the proliferation of acute myeloid leukemia cells

Abstract Objective To investigate the anti-proliferative effects of 20-hydroxyecdysone isolated from the bark of Dacrycarpus imbricatus (Blume) de Laub. Methods Column chromatography was used for isolation of compounds from plant material. The structure of the isolated compound was identified by mass spectrometry and nuclear magnetic resonance techniques, including HSQC, HMBC, NOE-difference experiments. The isolated compound was tested for its anti-proliferative activity in acute myeloid leukemia (AML) and OCI-AML cells. Results Compound 1 was isolated from the ethyl acetate fraction of Dacrycarpus imbricatus barks by column chromatography. Its chemical structure was identified as 20-hydroxyecdysone (20HE), a cholestane-type ecdysteroid, by a combination of mass spectrometry and nuclear magnetic resonance spectrometric analyses. Our goal was to test the anti-proliferative activity of 20HE using the OCI-AML cell line. 20HE significantly decreased OCI cell number at a concentration of 1 mg/mL, whereas lower concentrations were ineffective. Moreover, this decrease was due to partial blockage of the G 1 /S phase of the cell cycle, with a reduction of cells in the G 2 M phase, not due to increased apoptosis. Conclusions This indicates that 20HE significantly decreases the number of cells in the G 1 /S phase of the cell cycle in human AML cells. This is the first time that the anti-proliferative activity of 20HE against a human tumor cell line has been reported

Static and free vibration analyses of laminated composite shells by cell-based smoothed discrete shear gap method (CS-DSG3) using three-node triangular elements

A cell-based smoothed discrete shear gap method (CS-DSG3) using three-node triangular elements was recently proposed to improve the performance of the discrete shear gap method (DSG3) for static and free vibration analyses of isotropic Reissner-Mindlin plates and shells. In this paper, the CS-DSG3 is further extended for static and free vibration analyses of laminated composite shells. In the present method, the first-order shear deformation theory (FSDT) is used in the formulation due to the simplicity and computational efficiency. The accuracy and reliability of the proposed method are verified by comparing its numerical solutions with those of others available numerical results

XÂY DỰNG BỘ CHỈ TIÊU PHÁT TRIỂN BỀN VỮNG VỀ CÁC LĨNH VỰC KINH TẾ, XÃ HỘI VÀ MÔI TRƯỜNG CÁC TỈNH TÂY NGUYÊN

A  sustainable  development  indication  set  plays  a  very  important  role  for  assessing,  monitoring  the  sustainable development  status  in  a  region,  supporting  policy,  decision makers to  propose  confident  decisions  to control  economic, social, and environmental themes toward sustainable developmet. The content, procedure, methodology, and methods to establish the sustainable development indicator set in Tay Nguyen (SDI) were figured out; proposing a list of sustainable development indicators for Tay Nguyen consisting of 77 indicators at regional scale, 70 indicators at provincial scale, 49 indicators at district scale. The  SDI could comprehensively show overall development process toward sustainable by 13 themes (economic field - 3 themes; social field - 5 themes; and environmental field - 5 themes). The paper outlined the SDI’s definition and indicated SDI’s significance through linkages between the sustainable development indicators and sustainable development themes.ReferencesLê Thạc Cán, Trần Thùy Chi, Nguyễn Thế Chinh, Nguyễn Viết Thịnh, Ngô Đăng Trí, Nguyễn Thanh Tuấn, Trần Văn Ý và James Hennessy, 2013. Kết quả bước đầu của Đề tài “Nghiên cứu xây dựng Bộ chỉ tiêu phát triển bền vững các lĩnh vực kinh tế xã hội và môi trường các tỉnh Tây Nguyên”, Tạp chí Khoa học Công nghệ Việt Nam, ISSN 1859-4794. No14, 2013, p 61-64. Dhakal S. 2002. Report on Indicator related research for Kitakyushu Initiative. Ministry of Environment, Japan. Harold A. Linstone, Murray Turoff, 2002. The Delphi Method: Techniques and Applications. Hui-Chun Chu, Gwo-Jen Hwang, 2008. A Delphi-based approach to developing expert systems with the cooperation of multiple experts, Expert Systems with Applications, 34(4), 2826- 840. (SCI). Jean Hugé, Hai Le Trinh, Pham Hoang Hai, Jan Kuilman and Luc Hens, 2009. Sustainability indicators for clean development mechanism projects in Vietnam, Springer Netherlands. Environment, Development and Sustainability, August 2010, Volume 12, Issue 4, pp 561-571. Trần Văn Ý, Lê Thạc Cán, Trần Thùy Chi, Nguyễn Thế Chinh, Ngô Đăng Trí, Nguyễn Viết Thịnh, Nguyễn Thanh Tuấn, 2013. Bộ chỉ tiêu phát triển bền vững về các lĩnh vực kinh tế, xã hội và môi trường các tỉnh Tây Nguyên. Kỷ yếu hội thảo quốc tế lần thứ tư, Việt Nam học, Nhà xuất bản Khoa học xã hội, Hà Nội, ngày 26-28/11/2012, tập IV, 386-400. Bộ Kế hoạch và Đầu tư, 2010. Hệ thống chỉ tiêu thống kê quốc gia (Ban hành theo Quyết định số 43/2010/QĐ/TTg ngày 02 tháng 6 năm 2010 của Thủ tướng Chính phủ). UNDP và MPI, 2005. Identification of a sustainable development indicators set and mechanism for building a sustainable development database in Vietnam (Project VIE/01/021 “Implementation of Vietnam Agenda 21”) United Nations, 2007. Indicators of Sustainable Development: Guidelines and Methodologies. Thủ tướng Chính phủ, 2012. Các chỉ tiêu giám sát và đánh giá phát triển bền vững Việt Nam giai đọan 2011-2020 (Ban hành kèm theo Quyết định số 432/QĐ-TTg ngày 12 tháng 4 năm 2012 của Thủ tướng Chính phủ). Thủ tướng Chính phủ, 2013. Bộ chỉ tiêu giám sát, đánh giá phát triển bền vững địa phương giai đoạn 2013-2020 (Ban hành kèm theo Quyết định số 2157/QĐ-TTg ngày 11 tháng 11 năm 2013 của Thủ tướng Chính phủ). A  sustainable  development  indication  set  plays  a  very  important  role  for  assessing,  monitoring  the  sustainable development  status  in  a  region,  supporting  policy,  decision makers to  propose  confident  decisions  to control  economic, social, and environmental themes toward sustainable developmet. The content, procedure, methodology, and methods to establish the sustainable development indicator set in Tay Nguyen (SDI) were figured out; proposing a list of sustainable development indicators for Tay Nguyen consisting of 77 indicators at regional scale, 70 indicators at provincial scale, 49 indicators at district scale. The  SDI could comprehensively show overall development process toward sustainable by 13 themes (economic field - 3 themes; social field - 5 themes; and environmental field - 5 themes). The paper outlined the SDI’s definition and indicated SDI’s significance through linkages between the sustainable development indicators and sustainable development themes

Diterpenoids from Fokienia hodginsii.

In continuous research on the chemical constituents of the twigs and leaves of Fokienia hodginsii (Dunn) A. Henry et Thomas growing in Highland, Lam Dong province 4 diterpenoids, including 3-oxo-totarol (totarolone, 1), 3β-hydroxytotarol (2), 15-nor-labda-8(17),12E-diene-14-carboxaldehyde-19-oic acid (3) and 13-oxo-15,16-dinorlabda-8(17),11E-diene-19-oic acid (4) were isolated. Their structures were elucidated by the spectroscopic methods and comparison with reported data. This is the first report on the isolation of compounds 1, 2 and 3 from this plant. Keywords. Fokienia hodginsii; totarane; nor-labdane diterpenoid

Terpenoids from Dacrycarpus imbricatus.

The phytochemical investigation of the hexane extract from the twigs and leaves of Dacrycarpus imbricatus (Blume) de Laub led to the isolation of a rare sesquiterpene, spathulenol (1) along with three diterpenes named pimaric acid (2), trans-communic acid (3) and cis-communic acid (4). Their structures were determined by combination of spectral analysis and comparison with reported data. This is the first report on isolation of compound 1 from the Podocarpaceae family. Keywords. Dacrycarpus imbricatus, spathulenol, pimaric acid, communic acid

Experience in Using Mobile Laboratory for Monitoring and Diagnostics in the Socialist Republic of Vietnam

The aim was to present the experience of using mobile laboratory for monitoring and diagnostics (MLMD) during the epizootiological monitoring of the northern provinces of Vietnam. MLMD was transferred by Federal Service for Surveillance in the Sphere of Consumers Rights Protection and Human Welfare to the Socialist Republic of Vietnam as part of implementation of cooperation programs on combating infectious diseases. The use of MLMD made it possible to obtain new information on the circulation of pathogens of natural-focal infectious diseases on the territory of Vietnam. It also provided the necessary conditions for conducting research using methods of express diagnostics, bacteriological analysis, performing a full cycle of work – from the receipt of samples to the disinfection and destruction of infected material in compliance with the requirements of biological safety in the field. The effectiveness of using mobile laboratories in response to the emergencies of sanitary and epidemiological nature, both to strengthen stationary laboratory bases and to organize diagnostic studies in remote regions, has been shown. The use of MLMD for the diagnosis of COVID‑19 has been an effective component of countering the new coronavirus infection in Vietnam and significantly increased the volume of testing in the country

A New Megastigmane Glucoside and Other Constituents from Desmodium gangeticum

A new megastigmane glycoside, gangeticoside (1), and three known compounds leonuriside A (2), methyl benzoate 2-O-β-D-glucopyranoside (3), and tortoside A (4) were isolated from the aerial part of Desmodium gangeticum. Their structures were determined by 1D and 2D NMR spectra. The isolated compounds were evaluated for their inhibitory effect on NO production in LPS-stimulated RAW264.7 cells. Among them, compounds 1, 2, and 3 exhibited strong effect with the IC50 values of 22.3, 15.6, 7.3 μM, respectively

Antioxidant, Xanthine Oxidase, α-Amylase and α-Glucosidase Inhibitory Activities of Bioactive Compounds from Rumex crispus L. Root

The root of Rumex crispus L. has been shown to possess anti-gout and anti-diabetic properties, but the compounds responsible for these pharmaceutical effects have not yet been reported. In this study, we aimed to isolate and purify active components from the root of R. crispus, and to evaluate their anti-radical, anti-gout and anti-diabetic capacities. From the ethyl acetate (EtOAc) extract, two compounds, chrysophanol (1) and physcion (2), were isolated by column chromatography with an elution of hexane and EtOAc at a 9:1 ratio. Their structures were identified by spectrometric techniques including gas chromatography-mass spectrometry (GC-MS), electrospray ionization-mass spectrometry (ESI-MS), X-ray diffraction analyses and nuclear magnetic resonance (NMR). The results of bioassays indicated that (1) showed stronger activities than (2). For antioxidant activity, (1) and (2) exhibited remarkable DPPH radical scavenging capacity (IC50 = 9.8 and 12.1 µg/mL), which was about two times stronger than BHT (IC50 = 19.4 µg/mL). The anti-gout property of (1) and (2) were comparable to the positive control allopurinol, these compounds exerted strong inhibition against the activity of xanthine oxidase (IC50 = 36.4 and 45.0 µg/mL, respectively). In the anti-diabetic assay, (1) and (2) displayed considerable inhibitory ability on α-glucosidase, their IC50 values (IC50 = 20.1 and 18.9 µg/mL, respectively) were higher than that of standard acarbose (IC50 = 143.4 µg/mL). Findings of this study highlight that (1) and (2) may be promising agents to treat gout and diabetes, which may greatly contribute to the medicinal properties of Rumex crispus root

Tuning the magnetic phase transition and the magnetocaloric properties of La0.7Ca0.3MnO3 compounds through Sm-doping

In this work, we point out that the width and the nature of the magnetic phase transition, TC value, and as well as magnetocaloric effect in La0.7-xSmxCa0.3MnO3 compounds can be easily modified through Sm-doped into La-site. With an increasing Sm concentration, a systematic decrease in the magnetization, TC, and magnetic entropy change (ΔSm) are observed. The Arrott-plot proveds that the samples with x = 0 and 0.1 undergoing a first-order phase transition. Meanwhile, sample x = 0.2 undergoes a second-order phase transition, which exhibits a high value of the relative cooling power (81.5 J/kg at ΔH = 10 kOe). An analysis of the critical behavior based on the modified Arrott plots method has been done for sample x = 0.2. The results proved a coexistence of the long- and short-range interactions in La0.5Sm0.2Ca0.3MnO3 compound