Tropical cyclones likely enhance chemical weathering but suppress atmospheric CO2 consumption in landslide-dominated catchments

Biogeochemistry - The coupling between chemical weathering (including silicate, carbonate and pyrite weathering) and physical erosion is of high interest in active mountain belts. Participation of...     

Novel Method for Detection of Butanolides in Streptomyces coelicolor Culture Broth, Using a His-Tagged Receptor (ScbR) and Mass Spectrometry

γ-Butyrolactone derivative molecules in Streptomyces play a crucial role in cell density control, secondary metabolism, and cell differentiation. As their synthesis level in the cell is very low compared to those of similar N-acyl homoserine lactone molecules from gram-negative bacteria, it is very hard to analyze them even with several hundredfold concentration of the culture broth. We have developed a very quick and easy detection method using an affinity capture technique with His-tagged receptor proteins and electrospray tandem mass spectrometry. Using Streptomyces coelicolor as a model system, SCB1 was detected from only 100 ml of the culture broth after solvent extraction. This method can be further applied to detection and quantitative analysis of butanolides and inhibitor screening of the receptor molecules.     

Global stability of a predator-prey system

In this paper we derive a result to ensure the global stability of a predator-prey system. The method used is quite general and may have applications to other situations.Works were partially supported by the National Science Council of the Republic of China     

Analysis of the structure and expression of the c-myc oncogene in cervical tumor and in cervical tumor-derived cell lines

The structure of the c-myc oncogene in 17 cervical tumors and patient-matched nontumor tissues from Chinese patients residing in Taiwan was analysed. In contrast to recent reports on Mexican patients, none of the samples showed rearrangements and sequence amplification in the c-myc gene. The discrepancy may be explained by different carcinogenesis mechanisms being in operation in different geographic regions. Although no structural alterations in the c-myc gene were found in seven cervical carcinoma cell lines analysed, Northern blot analysis indicated different levels of c-myc gene expression which may be related to the presence of human papillomavirus (HPV) sequence in the cell and suggests a possible c-myc-hpv interaction in some stages of the transformation process.     

A Potent,Selective, Non-Substrate Inhibitor of HSV-I Thymidine Kinase: (±)-9-[[(Z)-2-(Hydroxymethyl)Cyclohexyl]Methyl]Guanine and Related Compounds

Abstract

The title compound was prepared and found to be a potent and selective inhibitor of HSV-I thymidine kinase. This compound delayed the reactivation of latent virus from explanted mouse ganglia but exacerbated the primary HSV-I infection in mice.