Streptogramin antibiotics are comprised of two distinct chemical components: the type A polyketides and the type B cyclic depsipeptides. Clinical resistance to the type B streptogramins can occur via enzymatic degradation catalyzed by the lyase Vgb or by target modification through the action of Erm ribosomal RNA methyltransferases. We have prepared through chemical and chemo-enzymatic approach...

A major challenge limiting the practical applications of nanomaterials is that the activities of nanostructures (NSs) increase with reduced size, often sacrificing their stability in the chemical environment. Under oxidative conditions, NSs with smaller sizes and higher defect densities are commonly expected to oxidize more easily, since high-concentration defects can facilitate oxidation by en...

Nuclear export of certain HIV-1 mRNAs requires an interaction between the viral Rev protein and the Rev response element (RRE), a structured element located in the Env region of its RNA genome. This interaction is an attractive target for both drug design and gene therapy, exemplified by RevM10, a transdominant negative protein that, when introduced into host cells, disrupts viral mRNA export. ...

In this work, we report a method to process porous silicon to improve its chemical resistance to alkaline solution attacks based on the functionalization of the pore surface by the electrochemical reduction of 4-nitrobenzendiazonium salt. This method provides porous silicon with strong resistance to the etching solutions used in optical lithography and allows the fabrication of tailored metalli...

Advanced transmutation systems require structural materials that are able to withstand high neutron fluxes, high thermal cycling, and high resistance to chemical corrosion. The current candidate materials for such structures are ferritic and ferritic-martensitic steels due to their strong resistance to swelling, good microstructural stability under irradiation, and the retention of adequate duc...

This session will focus on the fate and ecotoxicological effects of antibiotics, antibiotic resistance (AR) development and transfer in the environment and implications for human health. Specifically, we use the term antibiotic to include pharmaceutical agents with antibacterial properties. The scope of the session also extends to other chemical agents that can co-select for antibiotic resistan...

introduction: due to more resistance of pathogenic bacteria to new and current antibiotics researchers are looking to find the agents of herbal with antimicrobial activities in order to replace chemical drugs. methods: the herbal extract of withani somnifera was done by using a rotary vacuum, 20 strains of pseudomonas aeruginosa were isolated from urinary infections hospitalized patients in cit...

copper–silver bimetallic strips were produced by cold roll welding process and were treated by diffusion annealing in the temperature range 250–800 ?c. the interface bonding strength was determined by bending and peeling tests, resistance, conductivity and micro hardness profiles were determined and microstructure in the interface region was observed by optical microscope. electrical resistance...

Except for the chlorinated insecticides, all traditional insecticides and newly introduced IGR-type compounds have been investigated for their modes of action in respect to the resistance in diamondback moth, Plutella xylostella (L.) in Taiwan. Diamondback moth has a very active, efficient, and inducible mixed function oxidases (MFO) system/ complex, which is responsible for the high level of r...

In order to improve the chemical control of diamondback moth, Plutella xylostella (L), in Taiwan, the Taiwan Agricultural Research Institute organized in 1980 a program aimed at analyzing the insecticide resistance and mode of action. After almost five years of study, we have gathered information on the sampling method, resistance, cross resistance, the mode of insecticide action, and the effic...