摘要:

The induction potency of various (3-lactams as well as that of ‘nonspecific’ inducers such as the media employed or body fluids were studied in gram-negative clinical isolates and in their resistant corresponding counterparts. In all wild-type isolates quite a few (3-lactams (mainly cefoxitin and imipenem) shared the ability to induce the chromosomal ^-lactamase, whereas all (3-lactams – including 6-APS and 7-CPS clavu-lanic acid, and sulbactam (both (3-lactamase inhibitors), exhibited strong induction potency in their corresponding resistant counterparts. Moreover, all resistant counterparts exhibited the phenomenon of ‘nonspecific’ induction, whereas the wild-type strains did not. Interestingly, in both Proteus vulgaris 4917 W and Providencia rettgeri 862 W wild-type strains most P-lactam compounds were potent inducers, thus providing an explanation for resistance against P-lactamase-unstable compounds. The addition of subinhibitory concentrations of the quinolone compound enoxacin or chloramphenicol did not influence the phenotypic (3-lactamase expression, neither in wild-type strains nor in their resistant counterparts, whereas the addition of clindamycin or gentamicin resulted in a marked decrease of enzyme production in cephalosporinase overproducers, the P. vulgaris and the P. rettgeri

ISSN:0009-3157    

DOI:10.1159/000238634

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

Aztreonam is the first monobactam antibiotic to be used clinically. It is highly resistant to β-lactamases, and although its activity spectrum is similar to that of the aminoglycoside antibiotics, it has no effect on gram-positive bacteria. The current study was undertaken to determine the efficacy of aztreonam in treating gram-negative infections caused by multiresistant microorganisms in patients with known sensitivity to penicillins and cephalosporins. Sixty-six patients presented with urinary tract infection (UTI) and 30 with respiratory tract infection (RTI). All patients received aztreonam, between 4 and 6 g/day in divided doses for 10–14 days. Cure was achieved in 59 (89.3%) patients with UTI; in the group with RTI, 20 patients were cured and 4 improved with treatment. Tolerance to the drug was good in both groups, and in no instance did side effects necessitate modification of the dosing regim

ISSN:0009-3157    

DOI:10.1159/000238720

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

The activity of aztreonam (a β-lactam antibiotic with specific activity against gram-negative bacteria) was evaluated and compared with that of tobramycin in hospitalized patients with severe intra-abdominal infections due to gram-negative pathogens, either alone or in association with other bacteria. Of a total study population of 156 patients, 76 were assigned to treatment with aztreonam + clindamycin, and the remaining 80 were treated with tobramycin + clindamycin. Patients underwent a variety of surgical procedures involving the peritoneal cavity. The final clinical evaluation revealed similar percentages of satisfactory results: 86.8% for the patients in the aztreo-nam-treated group and 86.2% for the tobramycin-treated patients. Among the patients who had a poor therapeutic result, gram-negative bacteria, either alone or associated with gram-positive pathogens, were considered responsible for 50% of the infections in the aztreonam group; the percentage increased to 82% among those treated with tobramycin. The incidence of side effects and laboratory alterations was not significant and was similar in both groups. The results of this study suggest that aztreonam may be an effective and safe drug for the treatment of bacterial infections due to gram-negative pathogens

ISSN:0009-3157    

DOI:10.1159/000238721

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

The involvement of plasma testosterone in patients associated with scalp hair loss accelerated by anticancer drugs including aclarubicin and cisplatin was investigated. Scalp hair loss observed was minor in 12 and severe in 2 out of 31 patients. In patients without significant hair loss, the combination of aclarubicin and cisplatin produced a significant decrease in the plasma testosterone concentration in male patients and a significant increase in female patients 3 days after the anticancer chemotherapy. Six days after the chemotherapy, however, these concentrations returned to pretreat-ment values. Similar changes were observed in patients with minor or severe scalp hair loss induced by these drugs. These results suggest that aclarubicin and/or cisplatin may accelerate scalp hair loss with no adrogenic involvement.

ISSN:0009-3157    

DOI:10.1159/000238635

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

The preliminary results of four multicenter, comparative protocols on the efficacy and safety of aztreonam are discussed. This monobactam antibiotic was used as short-term prophylaxis in patients undergoing colorectal, gynecologic or urologic surgery. When compared with gentamicin in a group of 295 patients undergoing colorectal surgery, aztreonam significantly reduced the incidence of abdominal wound infection (p < 0.025); it also reduced the incidence of perineal wound and intra-abdominal infections, although these differences were not statistically significant. In patients undergoing abdominal and vaginal hysterectomy, aztreonam was compared with cefotaxime (both combined with clindamycin) in 170 and 142 patients, respectively. No difference in the incidence of infection was found between the two treatment regimens. In the 175 patients undergoing transurethral resection of the prostate, aztreonam was compared with placebo. The prophylactic regimen significantly reduced the number of urinary tract infections (p ≤ 0.0001). Its efficacy was particularly evident during the first 10 postoperative days. Side effects experienced by patients taking aztreonam were minor and similar in all three treatment groups studied. Aztreonam (alone or combined with clindamycin) offers a new and efficacious alternative to the standard antibiotic regimens currently used prophylactically in the high-risk postoperative patien

ISSN:0009-3157    

DOI:10.1159/000238722

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

Lonidamine (LND) interferes with the energy mechanisms of neoplastic cells and decreases the oxygen consumption in human and experimental tumors. The present study was performed in advanced non-small cell lung cancer patients, previously untreated, to confirm the preliminary data of activity against this kind of tumor. LND was given orally in three divided doses increasing to 250 mg/m2 over 4 days. Thirty-six patients were evaluable for toxicity and 33 for response. Partial responses were 3 (9%) and stabilization of disease 15 (45,5%). Recorded side effects (testicular pain, nausea and vomiting, skin hyperesthesia) were mostly mild to moderate with the exclusion of myalgias. Chronic treatment was devoid of haematological, renal, cardiac and pulmonary toxicities. LND as single agent seems to be marginally active in advanced non-small cell lung cancer.

ISSN:0009-3157    

DOI:10.1159/000238637

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

Foscarnet is shown to inhibit influenza A virus replication by inhibiting viral RNA synthesis in infected cells. Viral RNA synthesis by isolated nuclei from infected cells was as sensitive to foscarnet as viral RNA synthesis by enzymes from isolated virions or viral cores. It is, therefore, unlikely that the mere association of the polymerase in a replication complex, as in isolated nuclei and infected cells, is the reason for the fact that foscarnet is 10–20 times less active in inhibiting virus replication than cell-free RNA synthesis. We, therefore, tested 44 esters of foscarnet for improved antiviral effect. Of these only a few phenyl esters were more potent than foscarnet itself. These esters did not inhibit the viral RNA polymerase activity and may be hydrolyzed intracellularly to foscarnet. The increased antiviral potency of the phenyl esters was, however, accompanied by increased cellular toxicity, and these compounds, therefore, were less selective antiviral agents than foscarnet. The results suggest that it is not possible to increase the anti-influenza activity of foscarnet by converting it to an este

ISSN:0009-3157    

DOI:10.1159/000238638

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

The in vitro antibacterial activity of aztreonam was compared with that of cefoperazone, cefotaxime, ceftazidime, gentamicin, latamoxef, and ticarcillin against 140 clinical isolates of gram-negative bacteria. The activity of aztreonam against Entero-bacteriaceae is similar to that of cefotaxime and ceftazidime but greater than that of gentamicin, latamoxef, and ticarcillin. The 90% minimum inhibitory concentration (MIC90) of most of these isolates ranges between 0.8 and 1.6 μg/ml. The activity of aztreonam against Pseudomonas aeruginosa is similar to that of cefotaxime and cefoperazone, more active than that of latamoxef, and less active than that of ceftazidime. The minimum bactericidal concentration of aztreonam is equal to or twice the MIC for most strains tested. Time-kill studies of selected strains demonstrated rapid killing when they were exposed to 2–4 times the MIC of aztreonam. The selective spectrum of action of aztreonam makes this drug a useful agent in the therapy of a variety of gram-negative infectio

ISSN:0009-3157    

DOI:10.1159/000238723

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

A multicenter comparative study was carried out to evaluate the efficacy of aztreonam and gentamicin in 186 patients with symptomatic renal or urinary tract infections. Patients were divided randomly into two groups: 94 patients received aztreonam 1 g/day intramuscularly and 92 patients received gentamicin 80 mg i.m. twice daily. The clinical and microbiologic results found a single daily dose of aztreonam to be more effective than gentamicin b.i.d. Furthermore, no evidence of side effects was seen with aztreonam. Such results are generally thought to ensure better compliance in outpatients.

ISSN:0009-3157    

DOI:10.1159/000238724

出版商:S. Karger AG    

年代:1989

数据来源: Karger

摘要:

Gram-negative pneumonia is a frequent complication in hospitalized patients, particularly in those with diminished defenses. The severity of the infections makes it necessary to start immediately an empirical antimicrobial therapy that usually combines a broad-spectrum β-lactam antibiotic with an aminoglycoside (AMG), despite the potential toxicity of this regimen. We have compared the efficacy of a new β-lactam antibiotic, aztreonam, which shows both a specific spectrum of activity against gram-negative bacteria and a very good diffusion into pulmonary tissue, with that of another antibiotic regimen including an AMG. Of a total of 69 patients, 43 were treated with aztreonam and the remaining patients with an AMG. Both groups were comparable with respect to the severity of infection and underlying pathology. Clinical efficacy was similar in the two regimens (81% aztreonam, 62% AMG). However, antimicrobial efficacy was superior in the aztreonam group (88% aztreonam, 65% AMG), although differences disappeared in patients treated with the combination amikacin + cefotaxime or ticarcil-lin in the AMG group. Colonization/superinfection was also similar in both groups, although the selection of gram-negative bacteria occurred more frequently in the AMG group. Our results suggest that aztreonam, in monotherapy, may be a useful alternative for the treatment of gram-negative pneumoni

ISSN:0009-3157    

DOI:10.1159/000238725

出版商:S. Karger AG    

年代:1989

数据来源: Karger