Purified mu EBP-E binds to immunoglobulin enhancers and promoters

We describe the purification to apparent homogeneity of the murine immunoglobulin heavy-chain (IgH) enhancer-binding protein mu EBP-E from murine plasmacytoma cells by ion exchange and affinity chromatography. Glycerol gradient sedimentation, UV cross-linking, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis confirm that mu EBP-E is a 45-kilodalton molecular mass protein. Orthophenanthroline-copper chemical nuclease footprinting with purified protein has identified high-affinity binding sites for mu EBP-E within the IgH enhancer at the previously identified site E and at sites within IgH promoters and in the kappa light-chain enhancer. Equilibrium binding studies indicate that the dissociation constants for mu EBP-E binding to site E within the enhancer and to a binding site within the V1 heavy-chain promoter are quite low, about 2 x 10(-11) M. Comparison of four mu EBP-E recognition sequences detects only limited sequence similarity among binding sites.

Water quality control trials: statistical tables for direct comparison between membrane filtration bacterial counts and the multiple tube method with a description of the bacteriological method

Experiments in the quality control of water samples are being conducted in the Public Health Laboratory Service and the water industry in the United Kingdom. The number of distributions which have been made is 7 and 92 laboratories are now participating. The methods used for preparing and distributing samples are described. Some participating laboratories use the multiple tube method and some use membrane filtration to assess the presence of coliforms and Escherichia coli. The results are, therefore, a mixture of estimated numbers and direct colony counts. In order to compare results from these two different laboratory methods statistical tables have been compiled to show the most likely multiple tube result corresponding to each colony count. Tables relating to two commonly used tenfold dilution series are presented. To illustrate how these tables may be used we present results from a typical quality control distribution. The analyses of these results are generally satisfactory but show a tendency for lower counts using the membrane filtration method and more false negative results with E. coli counts.

Surgical procedures in patients during the tenth decade of life

The purpose of this study was to determine the outcome of major surgical procedures in patients 90 years of age or older. The records of 46 patients in this age group who underwent surgical procedures were reviewed to determine the outcome and the postoperative quality of life. Overall, the perioperative mortality was 20%. Mortality was not influenced by such risk factors as diabetes mellitus, chronic obstructive pulmonary disease, renal failure, quantity of blood loss, duration of procedure, or total number of hospital days. However, patients with heart disease had a significantly higher mortality rate (78%). Overall, 39% of the patients experienced a subjective deterioration in their mental status after surgery. Of those patients who were ambulatory before surgery, 73% were ambulatory after surgery. Although this study indicates that the perioperative mortality is high and mental status changes frequent in this very elderly age group, the quality of life and longevity of the majority of these patients are good, and vigorous surgical intervention appears warranted.

Preliminary pulsatile flow bench validation of a thermodilution right ventricular ejection fraction system

A preliminary Pulsatile Flow Bench validation of the REF-1 Right Ventricular Ejection Fraction (RVEF) computer and catheter system was performed to determine the accuracy of the current REF-1 system. These results reflect the accuracy of the current REF-1 system and not the final REF-1 system that will be released at a later date. The Pulsatile Flow Bench cardiac output and ejection fraction ranges included in this study are 1 to 6 Lpm and 15% to 60%, respectively. Currently, plans are being made to increase the flow bench cardiac output range to 10 Lpm with ejection fractions up to 70%. The results of this study show a correlation coefficient of 0.94 (adjusted R-square) between flow bench ejection fractions and REF-1 system ejection fractions. Also, the correlation coefficient between flow bench cardiac output and REF-1 system cardiac output was determined to be 0.99 (adjusted R-square).

Multiple DNA sequence elements are necessary for the function of an immunoglobulin heavy chain promoter

Sequences required for the function of the mouse V1 immunoglobulin heavy chain variable-region (VH) promoter were identified by transient transfection of the normal and mutated promoters into plasmacytoma cells. Our results identify four regions required for normal promoter function: (i) the octamer ATGCAAAT, previously identified by others; (ii) a heptamer, CTAATGA; (iii) a pyrimidine-rich region; and (iv) a region between positions -125 and -251 relative to the transcription start site. Sequence analysis of 19 mouse and human VH 5' flanking regions shows that the heptamer and pyrimidine stretch are strongly conserved. We have also demonstrated that the octamer functions in an orientation independent manner in the VH promoter.

Effect of reduced food intake on blood levels of a hypertensive factor in spontaneously hypertensive rats

We have previously demonstrated the existence of an active component(s) of extracts prepared from rat erythrocytes that stimulates the in vitro uptake of calcium in aortic rings and induces a sustained elevation in the blood pressure of normotensive rats. The apparent concentration of the calcium stimulatory component and the responsiveness of aortic rings to stimulation of calcium uptake by the compound is exaggerated in adult spontaneously hypertensive rats (SHR) compared with normotensive controls. Although no effect was observed on tissue responsiveness to the compound, a decrease in the concentration of the compound was observed in the blood of adult SHR subjected to dietary manipulation designed to blunt the elevation of blood pressure. These data suggest that blood concentration of the active compound may be influenced by external stimuli such as dietary manipulation.

The herpes simplex viruses: the facts health professionals need to know

Herpes labialis and herpes genitalis are described, including the symptoms, complications, treatment, and research of the disease. The article explains how transmission or contraction of the herpes virus occurs, particularly in the hospital setting, and how it can be avoided by the health professional.

The effect of oral potassium supplements on plasma potassium in normokalaemic and hypokalaemic patients

Thirteen out of 44 patients taking bendrofluazide 10 mg daily became hypokalaemic over a period of three months. Oral potassium supplements of 3.6 grams daily (48 mmol) given in addition to bendrofluazide for a further period of 3 months raised plasma potassium level significantly in hypokalaemic patients only. We conclude that where patients on diuretic therapy are followed up with plasma potassium measurements, it is generally necessary to prescribe oral potassium in the presence of hypokalaemia only.