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In susceptible strain of Bacteroides fragilis, tetracycline uptake is biphasic. The initial phase is independent of adenosine 5'-triphosphate synthesis, which is coupled to fumarate reduction; this phase is not altered by expression of tetracycline resistance genes in a resistant strain. The second phase appears to occur by active transport, since it is largely reduced by rotenone, an inhibitor of electron transport to fumarate; moreover, this phase is under negative control of the tetracycline resistance gene.

Ninety-two microbiologically documented staphylococcal infections were treated with cefamandole in an open comparative study on the clinical efficacy of this cephalosporin in the therapy of infections caused by both methicillin-susceptible and methicillin-resistant Staphylococcus aureus and coagulase-negative Staphylococcus spp. The majority of the episodes (86 of 92) were treated with cefamandole alone, and six were treated with cefamandole in association with other antibiotics. In the evaluable S. aureus infections, 34 of 46 (73.9%) due to methicillin-susceptible strains and 12 of 16 (75%) due to methicillin-resistant strains responded to therapy. In particular, among the patients infected by methicillin-susceptible S. aureus 6 of 9 cases of septicemia, 0 of 2 cases of endocarditis, 2 of 2 cases of pneumonia, 2 of 3 osteoarticular infections, 8 of 12 cases of peritonitis in patients with chronic renal failure in continuous ambulatory peritoneal dialysis (CAPD), 13 of 15 skin-soft tissue infections, and 3 of 3 urinary tract infections responded to therapy. Among those due to methicillin-resistant strains, cure was achieved in 2 of 4 cases of septicemia, 0 of 1 case of endocarditis, 9 of 10 skin-soft tissue infections, and 1 of 1 urinary tract infection. In the evaluable infections caused by coagulase-negative staphylococci, 9 of 11 (81.8%) due to methicillin-susceptible and 15 of 17 (88.2%) due to methicillin-resistant strains responded to therapy. In particular, among patients infected by methicillin-susceptible, coagulase-negative staphylococci, 4 of 4 cases of septicemia, 0 of 1 case of endocarditis, 1 of 1 case of pneumonia, 1 of 1 case of peritonitis in CAPD, 2 of 3 infections of skin-soft tissue, and 1 of 1 urinary tract infection responded to therapy. Among patients infected by methicillin-resistant, coagulase-negative staphylococci were cured 5 of 6 cases os septicemia, 6 of 6 cases of peritonitis (in CAPD), 4 of 4 infections of skin-soft tissue, and 0 of 1 urinary tract infection.

The transferability of plasmid-mediated tetracycline, erythromycin, and clindamycin resistance was studied in 63 clinical isolates of the Bacteroides fragilis group. Of 48 strains which were tetracycline resistant (Tcr), the regulation of both the expression of Tcr and its transferability was shown to be under inducible control by tetracycline. In 29 of the strains, Tcr was transferable; in the majority of these (26 strains), transferability was inducible (Trai) and it was constitutive (Trac) in only 3 strains. All four possible phenotypes were found (Tci Trai, Tci Trac, Tcc Trai, and Tcc Trac), which indicates independent control of both Tcr expression and its transferability. Resistance to erythromycin and clindamycin was cotransferred with Tcr in 14 of the 48 Tcr strains and transferred independently of Tcr in only 1 strain.