Mahidol University

About: Mahidol University is a education organization based out in Bangkok, Nakhon Pathom, Thailand. It is known for research contribution in the topics: Population & Malaria. The organization has 23758 authors who have published 39761 publications receiving 878781 citations.

Recent advances of capillary electrophoresis in pharmaceutical analysis

Abstract: This review covers recent advances of capillary electrophoresis (CE) in pharmaceutical analysis. The principle, instrumentation, and conventional modes of CE are briefly discussed. Advances in the different CE techniques (non-aqueous CE, microemulsion electrokinetic chromatography, capillary isotachophoresis, capillary electrochromatography, and immunoaffinity CE), detection techniques (mass spectrometry, light-emitting diode, fluorescence, chemiluminescence, and contactless conductivity), on-line sample pretreatment (flow injection) and chiral separation are described. Applications of CE to assay of active pharmaceutical ingredients (APIs), drug impurity testing, chiral drug separation, and determination of APIs in biological fluids published from 2008 to 2009 are tabulated.

The plant signal salicylic acid shuts down expression of the vir regulon and activates quormone-quenching genes in Agrobacterium

Abstract: Agrobacterium tumefaciens is capable of transferring and integrating an oncogenic T-DNA (transferred DNA) from its tumor-inducing (Ti) plasmid into dicotyledonous plants. This transfer requires that the virulence genes (vir regulon) be induced by plant signals such as acetosyringone in an acidic environment. Salicylic acid (SA) is a key signal molecule in regulating plant defense against pathogens. However, how SA influences Agrobacterium and its interactions with plants is poorly understood. Here we show that SA can directly shut down the expression of the vir regulon. SA specifically inhibited the expression of the Agrobacterium virA/G two-component regulatory system that tightly controls the expression of the vir regulon including the repABC operon on the Ti plasmid. We provide evidence suggesting that SA attenuates the function of the VirA kinase domain. Independent of its effect on the vir regulon, SA up-regulated the attKLM operon, which functions in degrading the bacterial quormone N-acylhomoserine lactone. Plants defective in SA accumulation were more susceptible to Agrobacterium infection, whereas plants overproducing SA were relatively recalcitrant to tumor formation. Our results illustrate that SA, besides its well known function in regulating plant defense, can also interfere directly with several aspects of the Agrobacterium infection process.

Theories of fertility decline and the evidence from development indicators.

Abstract: Some scholars have however questioned the empirical accuracy or theoretical implications of the three propositions. Hirschman and Mason (1997) for instance raise doubts about Proposition 2 although Mason also accepts Proposition 3. Galloway Hammel and Lee present evidence from nineteenth-century Prussia that is inconsistent with Propositions 2 and 3. Potter Schmertmann and Cavenaghi do the same for twentieth-century Brazil. This article also raises doubts about the accuracy of the three propositions and about their implications. It argues that fertility declines in countries with low development scores can in fact be accommodated by socioeconomic theories. It argues that socioeconomic theories predict only a moderately strong relationship between fertility and development indicators and demonstrates that the relationship between fertility and development is stronger than is generally believed. It then shows that the relationship has also been more stable than commonly thought. The conclusion is that socioeconomic theories fit the evidence from development indicators better than is generally realized. (excerpt)