Publications by authors named "Dinh Thi Quyen"

Through studies of new antimalarial drugs, we identified 1,2,6,7-tetraoxaspiro[7.11]nonadecane (N-89) as a potential drug candidate. Here, we analyzed the antimalarial action of a transdermal formulation (td) of N-89, designed for easy use by children, using Plasmodium berghei-infected mice as a model for malaria patients.

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Despite the recent progress in public health measures, malaria remains a troublesome disease that needs to be eradicated. It is essential to develop new antimalarial medications that are reliable and secure. This report evaluated the pharmacokinetics and antimalarial activity of 1,2,6,7-tetraoxaspiro[7.

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The discovery of new antimalarial drugs can be developed using asynchronized Plasmodium berghei malaria parasites in vivo in mice. Studies on a particular stage are also required to assess the effectiveness and mode of action of drugs. In this report, we used endoperoxide 6-(1,2,6,7-tetraoxaspiro [7.

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We have previously reported 1,2,6,7-tetraoxaspiro [7.11]nonadecane (N-89) as a promising antimalarial compound. In this study, we evaluated the effect of transdermal therapy (tdt) of N-89 in combination (tdct) with other antimalarials as an application for children.

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The discovery of new effective and safe antimalarial drugs is mandatory. In this report, we formulate and evaluate transdermal (td) 1,2,6,7-tetraoxaspiro[7.11]nonadecane (N-89) using the Plasmodium berghei rodent malaria parasite in vivo model.

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The streptokinase (SK) is emerging as an important thrombolytic therapy agent in the treatment of patients suffering from cardiovascular diseases. We reported highly effective renaturation of a SK from S. pyogeness DT7 overexpressed in E.

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Article Synopsis
  • A gene coding for an endo-β-1,4-xylanase (XlnA) from Aspergillus niger was successfully cloned, sequenced, and expressed in Pichia pastoris, showing high similarity to other A. niger strains.
  • The purified enzyme demonstrated a molecular mass of 35.5 kDa, specific activity of 808.5 U/mg, and optimal activity at 50°C and pH 7.0, with good stability under various conditions.
  • The enzyme was effective in breaking down birch wood xylan into oligosaccharides without cellulase or mannanase activity, indicating its potential use as a feed enzyme.
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A novel gene coding for an endo-beta-1,4-mannanase (manA) from Bacillus subtilis strain G1 was cloned and overexpressed in P. pastoris GS115, and the enzyme was purified and characterized. The manA gene consisted of an open reading frame of 1,092 nucleotides, encoding a 364-aa protein, with a predicted molecular mass of 41 kDa.

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A gene coding for an endoglucanase (EglA), of the glycosyl hydrolase family 12 and derived from Aspergillus niger VTCC-F021, was cloned and sequenced. The cDNA sequence, 717 bp, and its putative endoglucanase, a 238 aa protein with a predicted molecular mass of 26 kDa and a pI of 4.35, exhibited 98.

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A newly isolated gene from Ralstonia sp. M1, encoding an esterase, was cloned in Escherichia coli and its nucleotide sequence determined. The 1.

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Article Synopsis
  • The mature lipase LipA and its chaperone DeltaLipBhis were over-expressed in E. coli and effectively purified, with LipA displaying optimal activity between 50-55°C and maintaining significant activity up to 45°C.
  • The enzyme exhibited optimal performance at pH 10.75 for hydrolyzing olive oil and remained stable in an alkaline pH range, while showing resistance to various organic solvents, demonstrating its potential for industrial applications.
  • Metal ions had varying effects on lipase activity, with some enhancing and others inhibiting its function; the enzyme preferentially hydrolyzed triglycerides with shorter acyl chains and demonstrated significant activity with specific oils.
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Article Synopsis
  • The BTL2 lipase gene from Bacillus thermocatenulatus was successfully cloned into a pPICZalphaA vector and integrated into the Pichia pastoris GS115 genome, resulting in efficient extracellular production in a bioreactor.
  • The production yield reached an impressive 309,000 U/L, and the enzyme was purified, showing a specific activity of 23,000 U/mg towards tributyrin.
  • Characterization revealed that the BTL2 lipases produced in Pichia pastoris and Escherichia coli had similar physicochemical properties and high stability in the presence of organic solvents and detergents.
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