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What Is Known and Objective: Allopurinol, the first‐line medication for hyperuricemia is well‐known for its association with severe cutaneous adverse reactions, especially Stevens‐Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). In the current study, we analysed the Vietnamese spontaneous reporting database to identify signals and preventability of allopurinol‐induced SJS/TEN in Vietnam from 2010 to 2019. Methods: Signal generation was assessed using the case/non‐case method. Reporting odds ratios (RORs) and 95% confidence intervals (95% CI) were calculated. Results: Among 72,822 spontaneous ADR reports submitted to the Vietnam National Drug Information and Adverse Drug Reaction Monitoring Centre, 392 reports were on SJS/TEN, of which, 65 cases (16.6%) were related to allopurinol. The signals of allopurinol‐induced SJS/TEN in Vietnam started in 2014 (ROR of 3.531, 95% CI: 1.830–6.810) and annually increased until 2019 (ROR of 11.923, 95% CI: 8.508–16.710). The preventability assessment showed that no allopurinol‐induced SJS/TEN case was definitely unpreventable. 61.6% of the SJS/TEN cases were avoidable because they were associated with inappropriate prescribing such as unapproved indications, too high initial dose and even rechallenging in patients with a history of allopurinol allergy. What Is New and Conclusion: The signals of allopurinol‐induced SJS/TEN in Vietnam started in 2014 and annually increased until 2019. Our first report specifically focusing on the ADR preventability of allopurinol showed that correction of medical errors relating to prescription could prevent more than 60% of SJS/TEN cases in Vietnamese allopurinol users. This is a feasible and practical solution, provided that there would be a systematic change in both healthcare systems and public awareness. [ABSTRACT FROM AUTHOR]

2-Methoxypancracine is a montanine-type alkaloid exhibiting anti-inflammatory, antioxidant, and antibacterial effects. The bulbs of Hippeastrum reticulatum (L'Hér.) Herb. contain large amounts of 2-methoxypancracine. The aim of this study was to develop a HPLC-DAD method to quantify 2-methoxypancracine content in H. reticulatum. The HPLC analysis was carried out using a Poroshell 120 EC-C18 column eluted with acetonitrile and 0.01% methylamine (35:65, v/v) mixture in water at a flow rate of 0.5 mL/min with detection at 205 nm. Method validation was performed to assure its linearity, precision, accuracy, as well as the limit of detection (LOD) and limit of quantitation (LOQ). 2-Methoxypancracine displayed a linear relationship within a range of 2.5 – 103 μg/mL. The developed method was shown to be precise with relative standard deviation less than 2.5%. The average recovery of 2-methoxypancracine was 101.2. The LOD and LOQ values were calculated as 0.08 μg/mL and 0.25 μg/mL, respectively. The concentrations of 2-methoxypancracine in the alkaloid fraction and in the dried powder of H. reticulatum were 28.95%, and 0.0740%, respectively. The validated method provides a useful tool for the quantification of 2-methoxypancracine in H. reticulatum. This is the first report of significant 2-methoxypancracine content in H. reticulatum. [ABSTRACT FROM AUTHOR]

Gymnema is a genus of the Apocynaceae with more than 50 species. Some of its species such as G. sylvestre and G. latifolium have been reported for their medicinal value. In this study, the genetic diversity of 20 samples of four species of Gymnema in Vietnam was evaluated using the Random Amplification of Polymorphic DNA (RAPD) and the internal transcribed spacer of nuclear ribosomal DNA (ITS-rDNA). Amplified bands obtained with primers UBC701, UBC709, and OPC4 were the highest polymorphic in RAPD analysis. The phylogenetic trees were built grouping the 20 samples into four clusters corresponding to the four Gymnema species according to morphological classification. A number of characteristic SNPs were identified for each species which can be used for authentication and differentiation. The results showed the consensus and usefulness of the two barcoding techniques in the molecular identification and characterization of the Gymnema genus. [ABSTRACT FROM AUTHOR]

This research aims to identify the volatile compounds from rhizomes and leaves of Newmania sontraensis. The constituents of essential oil from the rhizomes and leaves of N. sontraensis were analyzed by Gas Chromatography-Mass Spectrometry (GC/MS). Thirty-one compounds were identified in the rhizomes compared to the leaves which showed thirty-two volatile compounds corresponding to 83.28 % and 76.41 % of the oil content, respectively. The chemical composition of the rhizome oil was characterized by hydrocarbon monoterpenes accounting for 36.26 %. The major compounds found in the rhizome oil included β-pinene (22.41%), 1,8-cineole (8.32 %), bicyclogermacrene (6.94 %), α-terpinyl acetate (5.74 %), α-pinene (5.71 %), and camphene (5.58 %). Meanwhile, sesquiterpene hydrocarbons were the main compounds found in the leaf oil accounting for 54.18 %. Bicyclogermacrene (14.60 %), δ-elemene (9.89 %), β-elemene (7.26 %), and α-terpinyl acetate (4.27 %) were determined to be the main components found in leaf oil. This was the first report on the chemical constituents of essential oils from rhizomes and leaves of N. sontraensis. [ABSTRACT FROM AUTHOR]

Subfraction E4.5 (390 mg) was separated on silica gel CC and eluted with gradient solvent mixture of CH SB 2 sb Cl SB 2 sb -MeOH (0->100%) to yield compound B 7 b (17 mg) and four subfractions (Subfrs. The ethyl acetate residue was separated by silica gel CC and eluted with a gradient solvent mixture of CH SB 2 sb Cl SB 2 sb -MeOH to yield 11 fractions (Frs. The I n i -hexane fraction was separated by chromatography column (CC) on silica gel and eluted with solvent gradient of I n i -hexane-ethyl acetate to afford 12 fractions (Frs. Subfraction E4.4 (40 mg) was purified on silica gel CC and eluted with solvent mixture of CH SB 2 sb Cl SB 2 sb -MeOH (9:1) to yield compound B 6 b (2 mg). [Extracted from the article]

Besides the critical functions in hemostasis, thrombosis and the wounding process, platelets have been increasingly identified as active players in various processes in tumorigenesis, including angiogenesis and metastasis. Once activated, platelets can release bioactive contents such as lipids, microRNAs, and growth factors into the bloodstream, subsequently enhancing the platelet–cancer interaction and stimulating cancer metastasis and angiogenesis. The mechanisms of treatment failure of chemotherapeutic drugs have been investigated to be associated with platelets. Therefore, understanding how platelets contribute to the tumor microenvironment may potentially identify strategies to suppress cancer angiogenesis, metastasis, and drug resistance. Herein, we present a review of recent investigations on the role of platelets in the tumor-microenvironment including angiogenesis, and metastasis, as well as targeting platelets for cancer treatment, especially in drug resistance. [ABSTRACT FROM AUTHOR]