RESUMO
The MICs of erythromycins A, B, C, and D and some of their derivatives were determined against 21 gram-positive and 15 gram-negative microorganisms. Antibacterial activity was confined to gram-positive and very few gram-negative bacteria. Erythromycin B was somewhat less active than erythromycin A, and erythromycin C and D showed about half that activity or even less. Most other derivatives had negligible activity. Determination of potency by diffusion and turbidimetric assays were in line with MICs. The examination of the results of these assays, however, revealed that there are differences between the data of different laboratories, depending on the microorganisms and conditions used.
Assuntos
Bactérias/efeitos dos fármacos , Eritromicina/análogos & derivados , Difusão , Eritromicina/farmacologia , Testes de Sensibilidade Microbiana , Nefelometria e TurbidimetriaRESUMO
Nosiheptide (9671 R.P.) isolated from Streptomyces actuosus 40037 (NRRL 2954) is a sulfur-containing polypeptidic antibiotic, quite different from all the other members of this family. Very active in vitro against gram-positive bacteria, it is inactive in vivo in experimentally infected mice. Not toxic, even at high dose, it may be used as a feed additive for chickens and pigs and it shows a favourable effect on the growth and conversion index.
Assuntos
Antibacterianos , Streptomyces/análise , Ração Animal , Animais , Bactérias/efeitos dos fármacos , Galinhas , Avaliação Pré-Clínica de Medicamentos , Aditivos Alimentares , Espectrometria de Fluorescência , Espectrofotometria Infravermelho , Suínos , Tiazóis/isolamento & purificação , Tiazóis/farmacologiaRESUMO
The C19 and C21 urinary steroids from a virilizing adrenal tumour with high levels of plasma 17alpha-progesterone and its urinary metabolites have been identified and quantitated by gas chromatography and mass spectrometry of sephadex fractions of the total urinary extract. Of the fifty five identified steroids thirteen were new compounds or known compounds not found before in such a case. The actiology of the apparent 21-steroid hydroxylase deficiency is discussed at the light of these analytical results and of the hormonogenesis enzymatic induction of the tumour biopsy.
Assuntos
Adenoma/urina , Neoplasias do Córtex Suprarrenal/urina , Neoplasias das Glândulas Suprarrenais/urina , Cromatografia Gasosa , Corticosteroides , Feminino , Humanos , Espectrometria de MassasRESUMO
The C19 and C21 urinary steroids from a virilizing adrenal tumour with high levels of plasma 17 alpha-hydroxyprogesterone and its urinary metabolites have been identified and quantitated gas chromatography and mass spectrometry of sephadex fractions of the total urinary extract. A of the fifty-five identified steroids thirteen were compounds not found before in such a case. The actiology of the apparent 21-steroid hydroxtlase deficiency is discussed at the light of these analytical results and of the hormonogenesis enzymatic induction of the tumour biopsy.