ACTIVITY OF AMPICILLIN IN VITRO COMPARED WITH OTHER ANTIBIOTICS

New N-Alkylated Heterocyclic Compounds as Prospective NDM1 Inhibitors: Investigation of In Vitro and In Silico Properties

A new family of pyrazole-based compounds (1–15) was synthesized and characterized using different physicochemical analyses, such as FTIR, UV-Visible, ¹H, ¹³C NMR, and ESI/LC-MS. The compounds were evaluated for their in vitro antifungal and antibacterial activities against several fungal and bacterial strains. The results indicate that some compounds showed excellent antibacterial activity against E. coli, S. aureus, C. freundii, and L. monocytogenes strains. In contrast, none of the compounds had antifungal activity. Molecular electrostatic potential (MEP) map analyses and inductive and mesomeric effect studies were performed to study the relationship between the chemical structure of our compounds and the biological activity. In addition, molecular docking and virtual screening studies were carried out to rationalize the antibacterial findings to characterize the modes of binding of the most active compounds to the active pockets of NDM1 proteins.

Microbial Resistance Movements: An Overview of Global Public Health Threats Posed by Antimicrobial Resistance, and How Best to Counter

Antibiotics changed medical practice by significantly decreasing the morbidity and mortality associated with bacterial infection. However, infectious diseases remain the leading cause of death in the world. There is global concern about the rise in antimicrobial resistance (AMR), which affects both developed and developing countries. AMR is a public health challenge with extensive health, economic, and societal implications. This paper sets AMR in context, starting with the history of antibiotics, including the discovery of penicillin and the golden era of antibiotics, before exploring the problems and challenges we now face due to AMR. Among the factors discussed is the low level of development of new antimicrobials and the irrational prescribing of antibiotics in developed and developing countries. A fundamental problem is the knowledge, attitude, and practice (KAP) regarding antibiotics among medical practitioners, and we explore this aspect in some depth, including a discussion on the KAP among medical students. We conclude with suggestions on how to address this public health threat, including recommendations on training medical students about antibiotics, and strategies to overcome the problems of irrational antibiotic prescribing and AMR.

A review of the microbiology of amoxycillin/clavulanic acid over the 15 year period 1978-1993

A review of the published literature over the period 1978-1993 was undertaken to assess any changes in the prevalence of beta-lactamase-producing bacterial pathogens and also any changes in the susceptibility in these pathogens to amoxycillin/clavulanate. The review has involved the examination of over 1500 publications. The review shows that in general there has been an increase in the frequency of beta-lactamase-producing pathogens resistant to ampicillin and amoxycillin but there is no evidence for any significant increase in resistance to amoxycillin/clavulanate over the period of the review.

Aminoglycoside-resistant enterococci

Thirty-four recent clinical isolates of Streptococcus faecalis were tested for sensitivity to amoxycillin, benzylpenicillin, streptomycin, kanamycin, gentamicin, tobramycin, and amikacin. Amoxycillin was two- to four-fold more active than benzylpenicillin and all strains were inhibited by low concentrations of the penicillins. The aminoglycosides were less active against the enterococci than were the penicillins and a significant number of strains were insensitive or relatively insensitive to one or more of the aminoglycosides. Thus, eight (23%) strains showed a high level of resistance to streptomycin and kanamycin (MIC greater 5000 microng/ml) but were sensitive to gentamicin, tobramycin, and amikacin. In addition, two strains of Strep. faecalis, isolated at different hospitals from patients who had received topical gentamicin therapy, were relatively resistant to gentamicin (MIC250 to 500 microng/ml) and were less sensitive also to the other aminoglycosides. Bactericidal synergy was demonstrated by amoxycillin/aminoglycoside combinations against the enterococci, provided that the test strain of Strep. faecalis was sensitive to the aminoglycoside in the combination. An exception to this was the combination of amoxycillin plus amikacin which was not synergistic against kanamycin-resistant strains of Strep. faecalis although these organisms were sensitive to amikacin in the growth inhibition tests. The gentamicin-resistant strains showed variable responses to amoxycillin/aminoglycoside combinations in tests for bactericidal synergy and were generally less sensitive than typical strains of Strep. faecalis.

5-hydroxy-7-chlortetracycline. I. Preparation, isolation, and physicochemical properties

Studies on pivampicillin hydrochloride and ampicillin trihydrate, administered in capsules to healthy volunteers, indicated that pivampicillin was absorbed more efficiently from the gastrointestinal tract than ampicillin. Average peak concentrations of ampicillin in the serum after doses equimolar to 250 mg of ampicillin were 6.8 μg/ml at 56 min with pivampicillin and 1.96 μg/ml at 1 h 24 min with ampicillin. The maximal concentration after pivampicillin treatment was also higher than that recorded when twice the equimolar dose of ampicillin, which averaged 3.2 μg/ml at 1 h 42 min, was used. The urinary excretion of ampicillin, expressed as a percentage of the administered dose, averaged 67 to 73 and 25 to 29% after administration of pivampicillin and ampicillin, respectively. The bioavailability of ampicillin, taken as the area under the serum curve, obtained with pivampicillin at a 250-mg ampicillin dose level was superior to that obtained with a 500-mg dose of ampicillin. Comparison of a suspension intended for children, containing the pivampicillin free base with a suspension of ampicillin trihydrate, emphasized the difference recorded for the capsule preparations. Administration of pivampicillin with a meal rich in fat and protein had no depressant effect on the absorption. Concurrent administration of probenecid caused higher and prolonged concentrations of ampicillin in the serum.

Sensitivity of Gram-negative bacilli to ampicillin after six years' clinical use

A total of 1,102 clinical isolates of Gram-negative bacilli was obtained from four hospitals during 1967 and these cultures were tested for sensitivity to ampicillin. Approximately 80% of the strains of Escherichia coli and 90% of the strains of Proteus mirabilis, the two organisms most frequently isolated, were sensitive to ampicillin. Klebsiella-Enterobacter species and Pseudomonas aeruginosa were generally insensitive. Comparison of these results with data obtained in an earlier study with Gram-negative organisms isolated in 1961 showed that there had been no significant increase in the incidence of resistance of Gram-negative bacilli to ampicillin during the period 1961-67. The majority of ampicillin-resistant strains of E. coli isolated in 1967 transferred ampicillin resistance to a sensitive strain of E. coli K12. Only four ampicillin-resistant strains of E. coli isolated in 1961 were available for transferable resistance tests but all four strains transferred ampicillin resistance. Infective or transferable resistance was therefore a feature of ampicillin resistance of certain Gram-negative bacteria before ampicillin became generally available for clinical use.