Search

We compare a rapid dilution method for the determination of antiviral susceptibility of herpes simplex virus (HSV) with the plaque reduction assay. A total of 84 HSV clinical isolates were studied by both methods to detect in-vitro resistance to acyclovir and foscarnet. The rapid method showed for the detection of HSV isolates resistant to acyclovir and foscarnet, a sensitivity of 96. 8% and 100% and specificity of 100% and 100%, respectively. This method provides an easy and accurate screening procedure for the susceptibility testing of HSV to antiviral agents.

The in-vitro activity of sparfioxacin and eight other antimicrobial agents against 64 non-tuberculous mycobacteria (non-MAI) (40 rapidly growing and 24 slowly growing) was compared with those of ciprofloxacin, ofloxacin, amikacin, tobramycin, cefoxitin, imipenem, clarithromycin and doxycycline. Sparfioxacin presented the same activity as ciprofloxacin, being highly active against rapidly growing mycobactena and showing good in-vitro activity against slowly growing mycobacteria. Amikacin was very active against rapidly growing mycobacteria and clarithromycin presented good activity against all mycobacteria tested. These results suggest that sparfioxacin is a valid agent to be considered in the treatment of Mycobacterium spp. infections.

The redox process undergone by the electrochemically synthesized poly(2,2′-dithiodianiline), poly(DTDA), has been examined in acetonitrile-water mixtures by electrochemical and spectroscopic techniques. The spectroscopic properties of this material are equivalent to those exhibited by the chemically synthesized one. The polymeric structure displays a ladder structure, with S-S bonds serving as interconnections between two adjacent polyaniline chains. The kinetic reversibility of the RS–SR⇌2RS−reaction is very poor for the DTDA monomer species, and this irreversibility is retained in the polymeric material. According to the results presented, the hypothesis that poly(DTDA) could display a high energy density due to the simultaneity of the leucoemeraldine⇌emeraldineand dithiolate⇌disulfideelectrochemical transformations does not seem justified.

The electrochemical oxidation of the aniline dimers 2-aminodiphenylamine (2-adpa) and 4-aminodiphenylamine (4-adpa) has been performed in strongly acidic medium on platinum, graphite, and indium tin oxide electrodes. The resulting films have been characterized by a number of electrochemical, microscopic, and spectroscopic techniques in order to gain some insight on their respective chemical structures. Both poly(2-adpa) and poly(4-adpa) are electroactive species which differ significantly one from another. It was found that aged poly(4-adpa) displayed electrochemical, morphologic and spectroscopic characteristics similar to those shown by polyaniline. On the contrary, poly(2-adpa) is really a mixture of three oligomerization products. The two main oligomers contain both open-ring and cycled phenazine centers, although their chemical structures seem to differ in the cap-end of the chain growth. The third oligomer is a minor product which seems a highly symmetric macrocycle involving several 2-adpa molecules.