Is There Normal Blood Flora?

摘要

Unknown microorganisms, which live as normal flora in every human's blood, were isolated in pure cultures and represented on microscope color microphotographs and electron microscope photographs in the blood of medical professors and associated professors. The aim of this article is to demonstrate 3 methods used as routine procedure in order to isolate normal blood flora in pure cultures. Introduction Indisputably, DNA-analyses are the most important discovery for microbiology (1, 2 ).The imperative condition that each newly discovered microorganism should pass over in silence unless DNA-analysis is not realized turns microbiology upside down, having in mind that tuberculosis, plague, cholera, etc. are found using only their isolation in pure cultures and not DNA-analyses.Pure cultures are the alpha and omega of microbiology in the past, present, and future because they allow a comprehensive study on newly discovered microorganisms, promoting their further DNA-analyses in every laboratory. Material And Methods Classic method for isolation of normal blood flora Liquid medium BBL? Brain Heart Infusion with 0.25% sodium citrate, 20 mg/L gentamicin and 50 mg/L chloramphenicol, is distributed in sterile test tubes, 4.5 ml in each, and is sterilized in autoclave at 121°C, for 15 minutes. 0.5 ml venous human blood is inoculated in a tube and cultured for 30 days, at 37°C.After centrifugation 5 min/3000 rpm/, a Gram's stained slide and a subculture sample on sheep blood agar (as contamination control sample) are prepared.Human blood agar Brain Heart Infusion with 1.2% Noble agar is sterilized at 121°C for 15 min, cooled at 50°C, mixed with 10% outdated human blood for transfusion and poured in plates. Positive blood culture sediment is inoculated evenly on the surface. Accelerate method for isolation of normal blood floraThe inoculated tubes are cultured at 43°C for 14 days instead at 37°C for 30 days .and treated as described above.Rapid method for isolation of normal blood flora with vitamin K3, or vitamin K1, 1g/L0.2 ml blood from a BD Vacutainer? K2E 5.4 mg 3 ml should be taken and 0.4 ml sterile bidistilled water must be added. The mixture is swayed to help erythrocyte hemolysis. After 30 minutes stay at room temperature the hemolytic erythrocytes are cultured in a test tube with 2 ml Brain Heart Infusion BBL? which contains also 1 mg/ml vitamin K3, or vitamin K1 as growth factor, at 43°C, for 3 days and treated as describe above. Results Classic method for isolation of normal blood floraUsing this method color pictures and electron microscope pictures were demonstrated in another articles (3, 4). The microorganisms were observed as spherical bodies inside human erythrocytes, situated as in nests. These unique nests are specific for normal blood flora microorganisms.Culture properties on human blood agar:After 28 days, normal blood microorganisms formed tiny gray colonies, which were almost invisible with a naked eye. The colonies were scanty. They were spherical, soft and easily removable by a loop.