ABSTRACT
Chlorcyclizine HCl and ciprofloxacin HCl were shown to have anti-HIV activity. They possess virustatic and virucidal activities against HIV, a murine retrovirus (RV) and several other RNA and DNA viruses. These drugs were screened from a large number of compounds on the basis of in vitro mutagenicity and antimetabolite detection tests. Subsequent studies were based on different exo vivo cell cultures. These two compounds were then tested on an animal model, following standard test protocols, using another retrovirus, maintained as Ehrlich's ascites cell tumour virus (EACTV). The animal mortality and protection tests corroborated the findings obtained in vitro, suggesting that these drugs acted synergistically against HIV, exhibiting both virucidal and virustatic properties.
Subject(s)
Anti-Infective Agents/pharmacology , Ciprofloxacin/pharmacology , HIV-1/drug effects , Histamine H1 Antagonists/pharmacology , Piperazines/pharmacology , Animals , Anti-Infective Agents/toxicity , Cells, Cultured , Chlorocebus aethiops , Ciprofloxacin/toxicity , DNA Viruses/drug effects , Drug Synergism , Histamine H1 Antagonists/toxicity , Humans , Male , Mice , Piperazines/toxicity , Retroviridae/drug effects , Vero CellsABSTRACT
Antimicrobial action of penicillin and some of its derivatives including fosfomycin was studied with respect to 225 strains of Gram-positive and Gram negative bacteria. Fosfomycin was found to possess somewhat less activity against Staphylococcus aureus compared with other penicillins; however, it showed powerful activity towards Escherichia coli, Klebsiella spp. and Proteus mirabilis.
Subject(s)
Anti-Bacterial Agents/therapeutic use , Fosfomycin/therapeutic use , Microbial Sensitivity Tests , beta-LactamsABSTRACT
The antibacterial and bactericidal activities of the antihistamine trimeprazine were studied against 243 strains of bacteria which included both Gram positive and Gram negative types. The susceptibility of these bacterial strains to trimeprazine was assessed by determining their minimum inhibitory concentration (MIC) which was found to be between 10 and 100 micrograms/ml. Nineteen strains of Staphylococcus spp. and Salmonella spp. were trimeprazine. Most of the strains belonging to Bacillus spp. and Salmonella spp. were inhibited by less than 100 micrograms/ml. Trimeprazine could also inhibit strains of Shigella spp. Vibrio cholerae and V. parahaemolyticus at 10-100 micrograms/ml. Strains of klebsiella, proteus, pseudomonas and citrobacter were moderately sensitive to trimeprazine. In in vivo studies it was seen that when trimeprazine was used at a concentration of 0.75 and 0.4 micrograms/gm body weight of the mouse both levels offered significant protection to Swiss mice challenged with 50LD50 of virulent strain of S. typhimurium 74. Statistical analysis of the data was found to be significant, p < 0.001 according to chi 2 test.
Subject(s)
Anti-Bacterial Agents/pharmacology , Histamine H1 Antagonists/pharmacology , Trimeprazine/analogs & derivatives , Animals , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , MiceABSTRACT
The antipsychotic drug fluphenazine was obtained in a dry powder form and was screened with respect to 482 strains of bacteria, which included 170 Gram-positive and 326 Gram-negative strains. Nutrient agar plates containing increasing concentrations of fluphenazine (0-200 micrograms/ml) were used for the determination of the minimum inhibitory concentration (MIC) which was demonstrated by inoculating a loopful of an overnight peptone water culture of the organism on nutrient agar plates and determining the MIC against a control. Fluphenazine was detected to possess pronounced action against both Gram-positive and Gram-negative bacteria at 20-100 micrograms/ml. In the in vivo studies it was seen that when fluphenazine was used at a concentration of 1.5 micrograms/g and 3 micrograms/g mouse body weight both the levels offered significant protection to Swiss strain of white mice when challenged with 50 minimum lethal dose (MLD) of a virulent strain of Salmonella typhimurium 74. The in vivo data with fluphenazine were highly significant (p < 0.001) according to the chi-square test.
Subject(s)
Anti-Bacterial Agents/pharmacology , Fluphenazine/pharmacology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Animals , Bacillus/drug effects , Enterobacteriaceae/drug effects , Mice , Microbial Sensitivity Tests , Salmonella Infections, Animal/drug therapy , Salmonella Infections, Animal/mortality , Salmonella typhimurium/drug effects , Staphylococcus/drug effects , Vibrionaceae/drug effectsABSTRACT
Different antibiotics were tested for their capacity to exhibit synergism when used in combination with promazine (Pr), a tranquilizer endowed with powerful antimicrobial property. For this purpose the minimum inhibitory concentration (MIC) of different antibiotics and Pr was first determined by spot inoculation technique on nutrient agar plates to select the concentrations of the antibiotics and Pr to be used as well as the sensitive strains. It was observed that Pr in combination with tetracycline (Tc) demonstrated a marked enhancement of the inhibitory capacity of each drug, both against the Gram-positive and Gram-negative bacteria, following disc diffusion technique. The in vitro findings were further substantiated with the in vivo effects of Pr along with Tc using Salmonella typhimurium NCTC 74 as the challenge strain in mice. The synergism obtained was further corroborated in terms of the increase in the size of their inhibition zones compared with their unaltered individual zones to determine the level of significance. This result was also confirmed by the checkerboard test using doubling dilutions of both the agents.
