Pilot scale exponential growth of Escherichia coli W to high cell concentration with temperature variation

An efficient method to grow Escherichia coli W to high cell concentrations on the pilot scale is described and discussed. The method involves growth linked introduction of glucose and ammonia to the culture, sparging with oxygen, and maintenance of aerobic conditions by gradually decreasing the temperature in the culture in order to keep the oxygen demand within the limits of the capacity of supply. Under these conditions the linear rate of cell mass production is actually the result of exponential growth with a gradually decreasing growth-rate constant. About 10 kg packed cells were produced in a 50 liter working-volume fermentor in one run of 13 hr. The concentration of the cells at the end of the growth was about 47 g dry cells/liter. The expenditure for nutrients was minimal and the controls were of simple automatic nature. From the determined yield constants for glucose, nitrogen, phosphorus, and oxygen it may be inferred that the cells grown by this method are similar to those grown exponentially at constant temperature.     

Clinical technique and success of the esophageal stent to prevent corrosive strictures

Membrane potential, Vm, and K+ (86Rb+) fluxes have been measured simultaneously on individual cells of Acetabularia mediterranea. During resting state (resting potential approx. -170 mV) the K+ influx amounts to 0.24-0.6 pmol-cm-2-s-1 and the K+ efflux to 0.2-1.5 pmol-cm-2s-1. According to the K+ concentrations inside and outside the cell (40:1) the voltage dependent K+ flux (zero at Vm = EK = -90 mV) is stimulated approx. 40-fold for Vm more positive than EK. It is calculated that during one action potential (temporary depolarization to Vm more positive than EK) a cell looses the same amount of K+, which leaks in during 10-20 min in the resting state (Vm = -170 mV). Since action potentials occur spontaneously in Acetabularia, they are therefore suggested to have a significant function for the K+ balance of this alga.     

Polycentric total knee arthroplasty. A two-year follow-up study

Polycentric total knee arthroplasty provided significant relief of pain in 86 per cent of 500 knees. The independence and activity levels of the patients increased dramatically. The frequency of major complications as reflected by reoperation was 10 per cent in this series. There was a 2.8 per cent deep infection rate. One-third of the infected knees were salvaged and two-thirds required arthrodesis. Loosening of a component was noted in 2.4 per cent. After operation the average range of motion was from 6 to 101 degrees of flexion, for a range of 95 degrees; this was a 5-degree increase over average preoperative motion. Ninety-six per cent of the patients expressed satisfaction with the surgical result.     

Idiopathic membranous glomerulonephritis

The only case of idiopathic membranous glomerulonephritis seen out of 106 nephropathic patients biopsied in the two last years at the C. H. 20 de Noviembre, I.S.S.S.T.E., is reported. Twenty-six showed nephrotic syndrome not associated to systemic disease, including the present case, which gave us an incidence of 3.8% of this entity. We were impressed by the low frequency of this disease, so we made a statistical epidemiological analysis localizing it geographically based on the available medical literature. On comparing the results of these studies we confirmed that this disease is significantly low in our environment.