Biomaterial Database

[Electron microscopic study of the effect of methicillin on phagocytized Staphylococcus aureus cells]. 1981

A S Seleznev, and A S Bykov

Morphological changes in phagocytized cells of Staph. aureus due to methicillin were studied with electron microscopy of ultrathin sections. Peritoneal macrophages of mice obtained by excitation of the abdominal cavity with medium No. 199 followed by infection with 1-milliard staphylococcal suspension were tested. Methicillin was administered in single doses of 2.5, 5, 25 and 50 mg/kg. The doses of 2.5 and 5 mg/kg induced specific changes in some cells. First of all the division septa were affected. After that the cell walls became thinner the cells increased in size, the cytoplasm became electronically less solid. No lysed cells were detected. The use of the doses of 25 and 50 mg/kg entailed polymorphism of the damages. Perforations formed in the bacterial cell wall. The cytoplasm acquired a characteristic granular structure evident of the cell death. With an increase in the dose from 25 to 50 mg/kg no rise in the level of the morphological changes in the bacterial cells was noted. Determination of methicillin concentration in the peritoneal exudate showed that it was 2--4 times higher depending on the dose than the MIC in vitro.

UI	MeSH Term	Description	Entries
D008712	Methicillin	One of the PENICILLINS which is resistant to PENICILLINASE but susceptible to a penicillin-binding protein. It is inactivated by gastric acid so administered by injection.	Penicillin, Dimethoxyphenyl,Methicillin Hydrate, Monosodium Salt,Methicillin Monohydrate, Monosodium Salt,Methicillin Sodium,Meticillin,Metin,Staphcillin,Dimethoxyphenyl Penicillin
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D010403	Penicillin Resistance	Nonsusceptibility of an organism to the action of penicillins.	Penicillin Resistances,Resistance, Penicillin,Resistances, Penicillin
D010587	Phagocytosis	The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (PHAGOCYTES).	Phagocytoses
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D004353	Drug Evaluation, Preclinical	Preclinical testing of drugs in experimental animals or in vitro for their biological and toxic effects and potential clinical applications.	Drug Screening,Evaluation Studies, Drug, Pre-Clinical,Drug Evaluation Studies, Preclinical,Drug Evaluations, Preclinical,Evaluation Studies, Drug, Preclinical,Evaluation, Preclinical Drug,Evaluations, Preclinical Drug,Medicinal Plants Testing, Preclinical,Preclinical Drug Evaluation,Preclinical Drug Evaluations,Drug Screenings,Screening, Drug,Screenings, Drug
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013203	Staphylococcal Infections	Infections with bacteria of the genus STAPHYLOCOCCUS.	Infections, Staphylococcal,Staphylococcus aureus Infection,Staphylococcal Infection,Staphylococcus aureus Infections
D013211	Staphylococcus aureus	Potentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.
D051379	Mice	The common name for the genus Mus.	Mice, House,Mus,Mus musculus,Mice, Laboratory,Mouse,Mouse, House,Mouse, Laboratory,Mouse, Swiss,Mus domesticus,Mus musculus domesticus,Swiss Mice,House Mice,House Mouse,Laboratory Mice,Laboratory Mouse,Mice, Swiss,Swiss Mouse,domesticus, Mus musculus