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Chemical investigation of the hexanes extracts of Ageratina jocotepecana afforded (-)-(5S,9S,10S,13S)-labd-7-en-15-oic acid (1), methyl (-)-(5S,9S,10S,13S)-labd-7-en-15-oate (2), (+)-(5S,8R,9R,10S,13R)-8-hydroxylabdan-15-oic acid (3), and (-)-(5S,9S,10S,13Z)-labda-7,13-dien-15-oic acid (5). The coexistence of (13R)- and (13S)-labdanes in this member of the Asteraceae family was demonstrated by vibration circular dichroism measurements of ester 2 and methyl (+)-(5S,8R,9R,10S,13R)-8-hydroxylabdan-15-oate (4) in comparison to the DFT B3LYP/DGDZVP-calculated spectra. In addition, transformation of 1 and 3 with HClO4 in MeOH yielded epimeric methyl (+)-(5S,10S,13S)-labd-8-en-15-oate (6) and methyl (+)-(5S,10S,13R)-labd-8-en-15-oate (7), respectively, confirming the presence of C-13 epimers in this plant. Diterpene 1 showed remarkable antibacterial activity against Bacillus subtilis (MIC 0.15 mg/mL) and Staphylococcus aureus (MIC 0.78 mg/mL), while diterpene 3 exhibited moderate activities against the same organisms.

A review of some antibacterial products is done motivated by the serious situation arisen by the antimicrobial resistance in bacteria. The attention is focus on those drugs with suitable antimicrobial properties that have prospects to be commercialized in the next years because of they are undergoing a clinical development phase (I, II, III). The search for these antibacterial products has been done by an exhaustive study of conference proceedings and web pages of international congresses on chemotherapy, infectious diseases and new antimicrobial drugs. Some of the new antibacterial products acts on known targets, and they belong to already used families. Furthermore, the great majority acts against the gram-positive bacterium. There is also some limited-spectrum antimicrobial drug whose use would minimize the adverse biological effects.

Numerous procedures used as antibacterial therapy are present in many films and include strategies ranging from different antimicrobial drugs to surgery and supporting measures. Films also explore the correct use and misuse of antimicrobial agents. Side effects and other aspects related to antibacterial therapy have also been reflected in some films. This article refers to the presence of antibacterial agents in different popular movies. There are movies in which antibacterial agents form part of the central plot, while in others it is merely an important part of the plot. In still others, its presence is isolated, and in these it plays an ambient or anecdotal role.

The antibacterial activity of BAY y 3118, a new chlorofluoroquinolone, was determined against 257 strains of anaerobic bacteria and compared with the activities of ofloxacin, ciprofloxacin, sparfloxacin, imipenem, cefoxitin, clindamycin, chloramphenicol, metronidazole, and ornidazole. Overall, BAY y 3118 was the most active agent tested against the Bacteroides fragilis group. Its activity (MIC90, 0.5 mg/L) was 16-fold lower than that of sparfloxacin (MIC90, 8 mg/L), and more than 100-fold lower than that of ofloxacin (MIC90, 64 mg/L) and ciprofloxacin (MIC90, 128 mg/L) against the group. No strains belonging to this group were resistant to metronidazole (MICs range, 0.12-2 mg/L) and ornidazole (MICs range, 0.12-4 mg/L). BAY y 3118 was more active than those quinolones against Prevotella and Porphyromonas spp., Fusobacterium spp., Clostridium perfringens and C. difficile (MIC90, 0.12, 0.06, 0.12 and 0.25 mg/L, respectively). The activity of BAY y 3118 against Peptostreptococcus spp. (MIC90, 1 mg/L) was slightly lower than that of the other Gram-positive bacteria tested. In general, BAY y 3118 was more active than cefoxitin, and it was superior to antianaerobic chemical agents like metronidazole, ornidazole and clindamycin. Pharmacokinetic and clinical trials are required to define the role of BAY y 3118 in the treatment of anaerobic infections.

Corynebacterium group D2 (CGD2) is involved in urinary tract infections in patients with underlying predisposing factors. This microorganism is highly resistant to a number of antimicrobial agents. We tested the activities of 79 antimicrobial agents against CGD2. beta-Lactams, aminoglycosides, and macrolides were ineffective. Fluorinated quinolones showed irregular activities, ofloxacin being the most active one. Doxycycline, rifampin, and mainly glycopeptides (vancomycin and teicoplanin) were the most active antibiotics against CGD2.

The activity of meropenem, a new carbapenem, as well as imipenem, ceftazidime, aztreonam, tobramycin, amikacin and ciprofloxacin against 18 strains of Xanthomonas maltophilia and 23 strains of Pseudomonas aeruginosa resistant to imipenem was tested. All strains of X. maltophilia were resistant to both penems. Ceftazidime, tobramycin and ciprofloxacin were the most active antimicrobial agents against this specie. 17% of imipenem-resistant strains of P. aeruginosa were sensitive to meropenem. Ciprofloxacin, amikacin and aztreonam were the most effective agents against these strains.

The susceptibility of 42 strains of Xanthomonas (Pseudomonas) maltophilia to 37 antibiotics (mainly beta-lactams, aminoglycosides, and fluorinated quinolones) was tested. Xanthomonas maltophilia was resistant to most beta-lactams, with ceftazidime, moxalactam, and ICI-194008 being the most active ones. Aminoglycosides had a very modest activity, with quinolones showing only moderate activity against this species. Trimethoprim/sufamethoxazole was effective against all strains tested. We also tested the synergy of several beta-lactam/beta-lactamase inhibitors against X. maltophilia. Only aztreonam/clavulanic acid at 3:1, 1:1 and, mainly, 2:1 combinations had synergistic activity, decreasing the rate of resistance from 92.8% for aztreonam alone to 32.4% for aztreonam-clavulanic acid at 1:1 and 0% for aztreonam-clavulanic acid at 2:1.

Campylobacter pylori has been associated with the etiology of gastritis and duodenal ulcer. It has been shown that several drugs, among them a variety of antimicrobials, eliminate C. pylori from gastric mucosa at least for a time, resulting in an improvement of the patients' symptoms. The activity of 16 antimicrobials (ampicillin, cefazolin, cefuroxime, cefotaxime, imipenem, aztreonam, tigemonam, erythromycin, vancomycin, nalidixic acid, colistin , norfloxacin, ciprofloxacin, difloxacin, ofloxacin and perfloxacin) was tested against 30 clinical isolates of C. pylori. The antimicrobials showing the highest activity were ampicillin, imipenem and ciprofloxacin, followed by cefazolin, cefuroxime, cefotaxime, aztreonam, tigemonam, erythromycin and difloxacin. Nalidixic acid, colistin and vancomycin were virtually ineffective against C. pylori.

The in vitro activities of amoxicillin, cefuroxime, ceftetrame, cefetamet, cefixime, tigemonam, erythromycin, roxithromycin, and dirithromycin against 30 clinical isolates of Campylobacter pylori were determined by an agar dilution technique. Roxithromycin and amoxicillin (MICs for 90% of isolates tested, 0.01 and 0.06 micrograms/ml, respectively) were the most active antibiotics tested, but all strains were susceptible to all antimicrobial agents tested.