摘要:

The studies reported in this paper were undertaken to investigate the hypothesis of Boyd, Covert and Pitman (Chemotherapia 11: 320, 1966) that the augmented toxicity of benzylpenicillin given orally to albino rates fed a synthetic pyridoxine-deficient diet was due to the presence of large amounts of sucrose in that diet. Benzylpenicillin potassium was given orally in a dose of 5.34 g/kg/day to young adult albino rats fed (a) a diet containing 22 % of casein, 69.4 % of sucrose, 4.0 % of salt mix, 2 % of hydrogenated vegetable oil, 2 % of cod liver oil, 0.5 % of wheat germ oil and adequate vitamin supplements (except pyridoxine) or (b) the same diet but with 69.4 % of cornstarch in place of the 69.4 % sucrose. The death rate and clinicopathologic signs of toxicity to benzylpenicillin were significantly greater in rats fed diet (a) than in those fed diet (b). It was concluded that the fulminating toxicity syndrome seen in animals fed diet (a) was due to a combination of the toxicity of subtoxic amounts of dietary sucrose and sublethal amounts of administered benzylpenicillin over the interval studied.

ISSN:0009-3157    

DOI:10.1159/000220659

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

The effect of the alkylating agent tris-(β-chlor- ethyl)-amine on glucose utilization in ascites tumor cells in vitro has been investigated. The influence of the unhydrolyzed and of the hydrolyzed agent was compared. Both affect the observed metabolic para- meters in comparable ways: They cause an increase in the rate of the oxidation of glucose C-6 to CO2, an increase in the level of glycolytic intermediates preceding the glyceraldehyde-phosphate dehydrogenase reaction, and an inhibition of lactic acid formation. In both cases the inhibition of lactic acid formation is counteracted by the addition of nicotinamide. Since the hydrolyzed drug, in contrast to the unhydrolyzed agent, does not exert a carcinostatic effect in vivo, the data provide additional evidence for the view that the cytostatic action is not the consequence of an inhibition of glycolysis

ISSN:0009-3157    

DOI:10.1159/000220660

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

Attempt was made to induce artificial resistance to sodium salt of N-succinyl perimycin using the method of subsequent passages on liquid media containing increasing concentrations of the antibiotic. Artificial resistance appeared late in the course of passages and its degree was rather low. Some physiological properties of the resistant strain and its morbidity curves were investigated, inhibiting and fungi-cidal concentrations of the investigated antibiotic were established as well.

ISSN:0009-3157    

DOI:10.1159/000220661

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

In vitro, antimicrobial activity of dodecyl-di(β- hydroxyethyl)-benzene ammonium chloride (DOBAC) and dodecyl-triphenyl-phosphonium bromide (DTPB), two surface active compounds, was tested in the presence of corticosteroids in doses which have been shown to enhance metabolic activity of bacteria. The experiments were performed with the Warburg technique measuring oxygen consumption of bacterial suspension in resting phase. Staph. aureus and B. pyocyaneus, three strains of each, served as test organisms. On Staph. aureus a marked decrease in antimicrobial activity of DOBAC and DTPB was encountered after addition of corticosteroids (hydrocortisone, methylprednisolone, fluocinolone). A similar, but weaker effect was present in B. pyocyaneus, too. These data suggest that in vitro tests should be performed before different chemotherapeutic are combined in one preparation

ISSN:0009-3157    

DOI:10.1159/000220662

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

Probit analysis was employed as a means for comparing the efficacy of different broad spectrum antibiotic treatments in conditions where uniformly high success rates can be obtained on the guide of experienced clinical judgment. With this method gains in efficacy can be established in terms of speed of effect on recovery or disappearance of symptoms. Relative potency estimate of a test drug compared to a reference drug is also possible under specified conditions. A controlled clinical trial was carried out in 2 series of infants hospitalized with acute lower respiratory tract infections; in the series with a diagnosis of acute bronchitis oral treatments with tetracycline and thiamphenicol (as palmitate) in syrup were compared and in the series with a diagnosis of pneumonia intramuscular treatments with ampicillin, chloramphenicol (as glycinate) and thiamphenicol (as glycinate) were compared. In the oral series a 12 % > shorter recovery time was demonstrated with thiamphenicol compared to tetracycline. In the intramuscular series the bactericidal agent, ampicillin, did not have a more rapid action than the bacteriostatic agents, chloramphenicol and thiamphenicol, on the basis of recovery times; the latter, and especially thiamphenicol brought about more rapid disappearance of dyspnea. This approach is suggested as suitable for comparing antibiotics in clinical practice.

ISSN:0009-3157    

DOI:10.1159/000220663

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

Carbenicillin was evaluated in 46 infections, mostly urinary tract and a few systemic, in the majority due to Pseudomonas aeruginosa. Of 39 urinary tract infections 17 were chronic pyelonephritides, 5 acute pyelonephritis, 15 cystitis, 1 urethritis and one kidney stone with infection. 30 were due to Pseudomonas alone, 1 to E. coli, 1 to Proteus, 1 to Staphylococcus, 3 to a combination of Pseudomonas and Proteus or E.coli, 2 to Proteus and E.coli and 1 to Klebsiella and Enterobacteriaceae. Of the 39, 22 showed excellent immediate clinical and bacteriological response, 12 improved and 5 failed. All 3 respiratory tract infections and one otitis (chronic) did not respond, perhaps due to insufficient dosage. Two septicemias showed excellent response with high doses (30 g daily). One had extensive burns and a critical condition. The other was in a more severe state: Pseudomonas septicemia with characteristic rash was superimposed on a severe icterus (mainly hepatocellular, partly hemolytic) with a severe sickle cell anemia crises in a girl with previous splenectomy. Carbenicillin administration was followed by dramatic effect and proved lifesaving. Carbenicillin is a useful agent for Pseudomonas and other Gram-negative infections. Urinary tracts respond fairly easily and patients previously resisting other treatments were finally cured with carbenicillin in moderate doses (3 g daily). Systemic infections require high doses (up to 30 g daily), sometimes assisted by the oral use of probenicid. The drug has been well tolerated, although the high doses present a problem for the veins and a bigger one for the pockets of the patient!

ISSN:0009-3157    

DOI:10.1159/000220664

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

Purine analogues, 8-azaguanine (2.5 µg/ml); 6-thio- guanine (5 µg/ml); 6-mercaptopurine (50 µg/ml); 6- chloropurine (50 µg/ml); and 2,6-diaminopurine (50 µg/ml); inhibited the thymine growth response of Streptococcus faecalis Akt., a Methotrexate (Lederle trade name for 4-amino-N10-CH3-folic acid) resistant mutant of S. faecalis. However, these same concentrations of the purine analogues did not influence the thymine growth response of the parent strain of S. faecalis. The inhibitory effect of 8-azaguanine or of 6-thioguanine on S. faecalis Akt., was of a competitive nature and was reversed by 5 µg/ml each of adenine or guanine or 5 µg/ml each of the nucleosides or nucleotides of adenine or guanine. Pyrimidine analogs 2-thiouracil (100 µg/ml); dithiothymine (500 µg/ml); and isobarbituric acid (100 µg/ml); inhibited the thymine growth response of S. faecalis Akt., but did not influence the thymine growth response of S. faecalis. The inhibitory effect of isobarbituric acid on the thymine growth response was reversed by cytosine (50 µg/ml); uracil (50 µg/ml); deoxycytidine (50 µg/ml); thymine (50 µg/ml); or thymidine (50 µg/ml). The results suggest that the S. faecalis Akt. has acquired de novo purine and pyrimidine biosynthetic pathways and is therefore inhibited by the analogs at lower concentrations. It may be speculated that clinical resistance to methotrexate may be associated with the acquisition of de novo purine biosynthetic capabilities in methotrexate-resistant cells and this opens a new avenue of attack on methotrexate-resi

ISSN:0009-3157    

DOI:10.1159/000220665

出版商:S. Karger AG    

年代:1970

数据来源: Karger

ISSN:0009-3157    

DOI:10.1159/000220666

出版商:S. Karger AG    

年代:1970

数据来源: Karger

ISSN:0009-3157    

DOI:10.1159/000220667

出版商:S. Karger AG    

年代:1970

数据来源: Karger