A chemically defined medium containing 18 amino acids, inorganic salts, rhamnose, choline, and ferric pyrophosphate has been developed. The final concentrations of salts and amino acids were modeled after yeast extract. This medium supported the growth of four serogroups of Legionella pneumophila. Growth in shake cultures at 37 degrees C produced a lag time of approximately 5 h and a generation time of 4 h with a maximum growth yield of 10 9 colony-forming units per ml. A soluble brown pigment was observed in the stationary phase of growth. The optimal pH was 6.3. Rhamnose and choline were stimulatory; arginine, serine, threonine, cysteine, valine, and methionine were essential. Supplemental iron was not required to attain maximum growth, but iron deprivation caused an extended lag phase.
A new, automated technique for the preparation of blood components is described. A system of 3 or 4 integrally connected plastic containers (Optipac) is handled by a new type of extractor (Optipress). The container in which the blood is collected has an outlet at the top and another at the bottom. After normal centrifugation to obtain separation of the blood components, these are squeezed out from the top and bottom simultaneously under control of a photocell. The primary separation step results in three components: a leukocyte-poor red-cell suspension in SAGM medium, CPD plasma, and a buffy-coat preparation. The system has been tested in two laboratories (lab A and lab B). A 'heavy-spin' centrifugation to obtain a maximum yield of cell-poor plasma gave the best removal of leukocytes from the red cells; the remaining leukocyte content was 0.46 +/- 0.25 (lab A) and 0.5 +/- 0.4 (lab B) x 10(9)/red-cell unit. Platelet concentrates can be prepared either the normal way via platelet-rich plasma or from buffy coat. Red-cell 24-hour autologous posttransfusion survival using labeling with 51Cr was 87.5 +/- 4.1% (lab A) after 35 days, and 84.2 +/- 4.2% (lab A) and 77.5 +/- 1.5% (lab B) after 42 days. Red-cell morphology and fluidity compared favorably to previous studies using the same additive solution in traditional plastic-bag systems. The total adenine nucleotide concentration was maintained normal for 42 days.(ABSTRACT TRUNCATED AT 250 WORDS)
Red cells stored under blood bank conditions normally show less than 1% spontaneous in vitro hemolysis even after 5 weeks; larger hemolysis may be found if the cells are suspended and stored in a saline-adenine-glucose (SAG) solution with very little trapped plasma. Delay of the addition of the suspension medium, return of 25 ml plasma after a maximal plasma harvest, addition of mannitol 10-30 mmol.1(-1) to the suspension medium were alternative and effective ways of keeping the spontaneous lysis within normal limits. Mechanical traumatization (centrifugation or shaking) caused considerably more damage to the red cells when these were highly concentrated than when they were diluted. A cell suspension in SAG is a more suitable product for hemotherapy than strongly packed red cell concentrates.
The medium described is a simple yeast extract broth capable of growing large number of Legionella neumophila, the causative organism of Legionnaires disease. Filtration was chosen as a means of sterilization, since medium that was autoclaved did not support growth without the presence of Norite A. The filtered medium gave rapid cell growth and maintained the initial antigen production. The observed generation time was 99 min with a maximum cell population of 2 X 10(2) COLONY-FORMING UNITS PER ML IN APPROXIMATELY 40 H.
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