Kidney Fragments Research Articles

Determination of protein and lipid lost during osmic acid fixation of tissues and cellular particulates.

Heart and kidney fragments and liver mitochondria and microsomes were prepared for electron microscopy by standard methods. The fixative, dehydration and embedding mediums each were analyzed separately for protein and lipid removed. It was demonstrated that protein and lipid were lost from mitochondria and microsomes and that protein was lost from tissue fragments during their preparation for electron microscopic examination. The significance of these results with respect to investigations concerned with the correlation of function to morphology is discussed.

Monolayer tissue cultures. II. Poliomyelitis virus assay in roller tube cultures of trypsin-dispersed monkey kidney.

SummaryThe preparation of roller tube cultures of trypsin-dispersed monkey kidney cells and their utilization for the assay of poliomyelitis viruses has been described. Data have been presented that show that cultures prepared in the manner described are more sensitive indicators of the presence of poliomyelitis virus infectivity than are cultures prepared from minced kidney fragments.

Poliomyelitis virus in tissue culture. VI. Use of kidney epithelium grown on glass.

Summary1. Monkey kidney epithelial cells can be cultured on glass without a plasma clot. The kidney fragments are induced to adhere to the wall of the test tube by preheating of the tube (45°C), and partial drying after introduction of tissue. These cultures compare well with cultures prepared in plasma clots, and respond as readily to the introduction of poliomyelitis virus. A great advantage is realized in the simplicity of preparation of these cultures, and their incubation in stationary racks. Exclusive of preliminary preparations and subsequent stoppering of the tubes, two trained workers can prepare well over 1000 cultures in 1 hour. About 2000 such cultures can be provided from a single monkey. 2. Bottle cultures can be prepared by the same technic, and have yielded poliomyelitis virus titers of about 10-6 per 0.1 ml inoculum. Titers in tubes or bottles reach their maximum in 24 to 72 hours depending upon the dose of virus inoculated. 3. After a culture has grown to satisfactory dimensions, origina...

Media and methods for separation and cultivation of oral spirochetes

Methods and media are described for the separation of oral spirochetes from associated bacteria and for maintenance of such separated cultures. The primary culture technique utilizes special small, deep Petri dishes and a “hormone” agar clarified with the aid of filtration through glass wool and sintered glass, enriched with 30 per cent ascitic fluid and 0.1 per cent cysteine hydrochloride, and containing minced fresh guinea pig kidney. Inoculation was made into a well in the center of the plate, and after anaerobic incubation separated spirochetes were easily obtained through the sterile agar surface. The “hormone”-ascitic fluid-cysteine-kidney (AFK) medium proved more satisfactory for cultivation of spirochetes than several others tested. Serum ultrafiltrate, alone or diluted with Simms' salt solution, was less satisfactory than ascitic fluid. Media containing 1 or 10 per cent of ascitic fluid, or 1 per cent of defibrinated or laked rabbit blood, were also less useful. Omission of kidney resulted in distinct diminution of growth, but kidney fragments could be replaced by a clear aqueous kidney extract. The agar concentration could be reduced from 1.2 per cent to 0.1 per cent without appreciable impairment of growth, but elimination of agar yielded erratic results. Neither the “hormone” base nor several other bases tried yielded consistent growth in agar-free media. A commercial dehydrated heart infusion base gave growth nearly equal to that obtained with the “hormone” base, but fresh tissue or extract was found to be more essential with the former. The findings with 25 separated strains of oral spirochetes, 15 of which were studied in subculture, did not permit adequate classification of the strains because of variability in morphology and growth characteristics. Such findings may be inherent in the Noguchi technique, upon which the present methods were based, like nearly all other methods for growing oral spirochetes. This and other unsolved problems in this field are discussed.