The human phosphoglycerate kinase multigene family. HLA-associated sequences and an X-linked locus containing a processed pseudogene and its functional counterpart

Several phosphoglycerate kinase genes were previously detected in the human genome by blot hybridization with a phosphoglycerate kinase cDNA probe. Using subcloned fragments of the cDNA we estimate the presence of four independent phosphoglycerate kinase genes. These genes have been mapped to both the human X chromosome (band q13) and chromosome 6 (p12-21.1) using a panel of human-rodent somatic cell hybrids and by chromosomal in situ hybridization. The genomic distribution of phosphoglycerate kinase sequences is conserved in man and mouse, not only for the X chromosome, but also for linkage to the respective major histocompatibility complexes. Molecular cloning of X-linked phosphoglycerate kinase sequences led to the identification of a novel intronless phosphoglycerate kinase pseudogene which is localized proximal to the active gene on the X chromosome.     

Control of 3T3 cell proliferation by calcium

Summary When a population of 3T3 mouse cells was subcultured regularly at confluency, the original epitheliodid or stellate cells disappeared and, by the ninth passage, they had been replaced by spindle-shaped cells. The original cells proliferated only when the extracellular calcium concentration exceeded 0.1mm, and their proliferative activity became maximum only when the calcium concentration was 0.5mm. The spindle-shaped cells were much more sensitive to proliferative stimulation by calcium. Although these cells also could not proliferate without extracellular ionic calcium, they proliferated maximally in the presence of as little as 0.05mm calcium. Thus, calcium is a major regulator of the proliferation of 3T3 mouse cells. Moreover, it appears that the sensitivity of the proliferative machinery to the calcium ion can vary greatly within an established cell line.     

Basic equipment requirements for hemodynamic monitoring.

Hemodynamic monitoring in the critically ill patient requires the use of sophisticated electronic devices. To use this equipment one should have a general understanding of the principles involved and the requirements of a reliable system. This communication serves to explain the requirements of the various components of a hemodynamic monitoring system and to demonstrate how they interact to produce accurate and safe electronic signals from mechanical wave forms obtained from the patient.     

Management of acute coronary occlusion during percutaneous transluminal coronary angioplasty: experience of complications in a hospital without on site facilities for cardiac surgery.

OBJECTIVE--To determine whether percutaneous transluminal coronary angioplasty may be safely performed in cardiology centres in the United Kingdom without immediate on site cardiac surgical cover for complications arising at angioplasty. DESIGN--Retrospective review of coronary angioplasties and complications in a hospital without on site cardiac surgical cover. SETTING--All angioplasties were performed in the catheterisation laboratory of the Belfast City Hospital. Revascularisation surgery for complicated coronary angioplasty was performed in the cardiac surgical unit of the Royal Victoria Hospital, 2.4 km away from the catheterisation laboratory. PATIENTS--540 Coronary angioplasties were performed on 512 patients between late 1982 and November 1988. Indications included stable angina, unstable rest angina, and suitable coronary disease at coronary arteriography after myocardial infarction. MAIN OUTCOME MEASURES--In hospital mortality after complicated coronary angioplasty and delay to surgical revascularisation after acute coronary occlusion at angioplasty. RESULTS--Coronary angioplasty was successful in 444 cases (82%). Acute coronary occlusion occurred in 35 cases (6.5%). Twelve patients required urgent revascularisation surgery and were transferred safely to the surgical unit; none of these patients died. A mean delay of 268 minutes (range 180-390 minutes) occurred before revascularisation compared with 273 minutes (range 108-420 minutes) in the Royal Victoria Hospital, where on site surgical cover was available. The principal cause of delay was the wait for a cardiac operating theatre to become available and not the transfer time between hospitals. Five deaths occurred after coronary angioplasty, a mortality of 0.9%. Three deaths were related to acute coronary occlusion. The absence of immediate surgical help did not influence the outcome in any patient. CONCLUSION--With careful selection of patients coronary angioplasty may be safely performed in a hospital without on site cardiac surgical facilities, provided that these are available at a nearby centre.