Peptides from live yeast cell derivative stimulate wound healing

Live yeast cell derivative is an alcoholic extract from yeast (Saccharomyces cerevisiae) that has previously been shown by three groups of workers to stimulate wound healing. Live yeast cell derivative is a complex mixture, and it was not known which of its many components was responsible for the biological activity. This study describes the separation and analysis of the major components, one of which is a peptide fraction that stimulates wound healing. The fraction consists of a mixture of peptides from 6000 to 17,000 d. It causes angiogenesis in a chick embryo yolk sac membrane assay and in a rabbit cornea assay, and it dramatically stimulates wound healing in the "Schilling/Hunt" wire mesh cylinder model at concentrations 25-fold lower than those required for the intact live yeast cell derivative.

Influence of local anesthetic solution on postdural puncture headache

A total of 2,511 patients who received spinal anesthesia for cesarean delivery were observed for the development of postdural puncture headache (PDPH); 804 patients received a mixture of tetracaine and procaine, 942 received bupivacaine-glucose, and 765 received lidocaine-glucose. They were observed for the development of PDPH for a minimum of 72 h. PDPH occurred in 9.54% of patients who received lidocaine-glucose during the first 36 h compared with 7.64% of patients who received bupivacaine-glucose and 5.85% of patients who received tetracaine-procaine. The differences between all groups was statistically significant. No differences were found in the percentage of patients who ultimately required epidural blood patch for relief of symptoms after 36 h.

Endothelial cell-stimulating angiogenesis factor in vitreous from extraretinal neovascularizations

The presence of endothelial cell-stimulating angiogenic factor (ESAF) in diseased human vitreous humour has been established. The molecular mass and chromatographic behavior of this material and its property of activating procollagenase indicate it to be identical to the ESAF isolated from other sources. The biological activity of ESAF from human vitreous was demonstrated by its ability to induce positive responses in the rabbit corneal pocket, and in the chick chorioallantoic membrane and yolk sac membrane tests.

Factors influencing the in vitro translocation of the Escherichia coli maltose-binding protein

An in vitro system has been utilized to study the translocation of newly synthesized Escherichia coli maltose-binding protein (MBP) into inverted membrane vesicles. Approximately 40% of precursor MBP (pMBP) synthesized with a wild-type signal peptide was imported into vesicles. However, MBP species with even minor alterations in the signal peptide hydrophobic core were imported into vesicles with an efficiency much lower than predicted from in vivo studies. Posttranslational import of wild-type pMBP into vesicles could be demonstrated if membranes were added after the termination of protein synthesis. However, if vesicles were present throughout the synthesis reaction, most pMBP import occurred either cotranslationally or very soon after completion of synthesis. The wild-type pMBP rapidly became incompetent for posttranslational translocation upon continued incubation in the absence of membranes, whereas pMBP species with altered folding properties remained competent for significantly longer periods. The rate of in vitro pMBP folding was affected by the nature of the signal peptide. The evidence suggests that one or more soluble factors may interact with the newly synthesized pMBP to help maintain it in a translocation-competent state and to promote its entrance into the export pathway.

Anesthetic-related maternal mortality, 1954 to 1985

This is a population-based study of the safety of obstetrical anesthesia in the Commonwealth of Massachusetts between 1954 and 1985. We used data collected by the state Committee on Maternal Mortality, which was founded in 1941. There were a total of 37 maternal deaths during the study period due to anesthetic-related complications. During the same time period, there were 886 maternal deaths. Thus, anesthetic-related mortality comprised 4.2% of all deaths, and the mortality rate was 1.5 per 100,000 live births between 1955 and 1964, 1.5 per 100,000 live births between 1965 and 1974, and 0.4 per 100,000 live births between 1975 and 1984. In the first decade of this study, aspiration during administration of a mask anesthetic was the primary cause of death. During the second decade, cardiovascular collapse associated with regional anesthesia was the primary cause of death. During the last decade of this study, all deaths were associated with general endotracheal anesthesia. As a result of this study and having identified the changes in the standard of care in Massachusetts that led to the reduction in maternal mortality, we offer recommendations to further improve the safety of anesthesia for childbirth in this country.

Purified secB protein of Escherichia coli retards folding and promotes membrane translocation of the maltose-binding protein in vitro

The efficient export of a subset of Escherichia coli envelope proteins is dependent upon the product of the secB gene. Previous studies indicated that SecB promotes the export of the periplasmic maltose-binding protein (MBP) by preventing premature folding of the precursor MBP in the cytoplasm into an export-incompetent form. In this study, SecB has been purified to homogeneity and shown to be a soluble, cytoplasmic, multimeric protein composed of identical 17-kDa subunits. SecB was required for efficient in vitro translocation of MBP into inverted membrane vesicles. The addition of purified SecB to an in vitro system prepared from SecB- cells significantly enhanced MBP translocation. The purified protein also quantitatively retarded folding of precursor MBP into a stable, protease-resistant conformation in the absence of membranes. Finally, the inclusion of excess purified SecB in a SecB+ in vitro system significantly prolonged the time in which precursor MBP remained competent for posttranslational import into membrane vesicles.

Neovascularisation and its role in the osteoarthritic process

In osteoarthritis angiogenesis is involved in the reinitiation of cartilage growth and mineralisation. A number of heparin binding protein growth factors have been proposed as angiogenic factors, but none of them is specific for microvessel cells. Another factor which is specific for microvessel cells, is of low molecular weight and non-profit has been called endothelial cell stimulating angiogenic factor (ESAF). ESAF has been found in significantly increased amounts in sera and synovial fluids of osteoarthritic patients and dogs. In addition to its angiogenic activity ESAF is able to activate neutral prometalloproteinases and to reactive the active enzyme-inhibitor complex. The implication of these observations in the pathogenesis of osteoarthritis is discussed.

The antifolding activity of SecB promotes the export of the E. coli maltose-binding protein

Evidence is presented that the E. coli secB gene encodes a soluble protein that interacts with the mature region of the precursor maltose-binding protein (MBP), and promotes MBP export by preventing premature folding of the newly synthesized polypeptide into an export-incompetent form. The interaction of SecB with MBP was indicated by the finding that synthesis of various export-defective MBP species interfered with normal protein export by limiting SecB availability. The antifolding activity of SecB was demonstrated by the following: the defect in MBP export in SecB- cells was suppressed by mutational alterations affecting MBP folding; export of a mutant MBP that is accomplished in a strictly posttranslational mode was totally blocked in SecB- cells; and the rate of folding of wild-type MBP synthesized in vitro was found to be accelerated when SecB was absent and greatly retarded when excess SecB was present.

Bovine and human pineal glands contain substantial quantities of endothelial cell stimulating angiogenic factor

Using a quantitative assay the amount of a low Mr endothelial cell stimulating angiogenesis factor (ESAF) has been determined in human pineal glands and bovine brain, retina, pineal gland, liver and kidney. Pineal glands contain approximately ten times as much ESAF as the retina or grey and white matter from the cerebral cortex and a hundred times as much as highly vascular tissues such as liver and kidney. The relevance of these findings to the highly vascular nature of the pineal gland is discussed.

[Idiopathic bi-auricular dilatation manifested by total cardiac failure. Apropos of a case confirmed by nuclear magnetic resonance]

Idiopathic bilateral atrial dilatation is extremely rare. We are reporting a case in a 79 year-old patient, presenting a picture of total cardiac insufficiency. The positive diagnosis was established by bi-dimensional sonography and right angiography. Nuclear magnetic resonance confirmed the diagnosis and specified the size of the various cavities. From a rhythm standpoint, there was an atrial fibrillation without conduction disorders. The main factor of the cardiac insufficiency seems to be a low atrio-ventricular output, since the valvular insufficiency due to annular dilatation is only a secondary factor. The etiology is unknown, but a congenital origin seems most probable without excluding the possibility of an acquired structural disorder.

Increased procollagenase activating angiogenic factor in the vitreous humour of oxygen treated kittens

Previous studies have demonstrated an increase in a low molecular weight angiogenic factor (ESAF) present in the retinae of kittens with oxygen induced retinopathy. The present paper describes differences in the quantity of ESAF extracted from the vitreous humour of control and oxygen treated animals and proposes a mechanism for the induction of intravitreal neovascularisation.

Epiphyseal growth plate cartilage and chondrocytes in mineralising cultures produce a low molecular mass angiogenic procollagenase activator

We have investigated one aspect of the biochemical control of angiogenesis in the mammalian growth plate. This is the first report of an angiogenic compound from normal growing skeletal tissue. The active agent was indistinguishable from ESAF (endothelial cell-stimulating angiogenic factor), previously identified from tumour, retina and synovial fluid. 1. Using a procollagenase activation assay, ESAF was detected in low molecular weight extracts of growth plate cartilage from two species (foetal calf and young rabbit). ESAF content declined with increasing age of the foetal calf growth plate cartilage. 2. Rabbit growth plate chondrocytes in high density culture also produced ESAF 24-48 h after calcification of the culture. Inhibition of alkaline phosphatase in these cultures reduced the stimulation of ESAF production. These findings suggest that ESAF production occurs as a stage in chondrocyte differentiation which is linked with the onset of matrix calcification. A model is proposed for the control of angiogenesis in the growth plate.

Schistosoma mansoni: stimulation of artificial granuloma formation in vivo by carbohydrate determinants

A subset of Schistosoma mansoni egg glycoproteins that share a common carbohydrate epitope recognized by monoclonal antibody 128C3 was shown to induced formation of hepatic granulomata when conjugated to Sepharose beads and injected into the portal circulation of naive mice. Concanavalin-binding egg glycoproteins exhibited more granuloma-inducing activity than did total egg extract, although deglycosylated egg proteins also induced granulomata; thus, both amino acid and carbohydrate epitopes appeared to be involved. Glycoproteins derived from adult male worms also were active, indicating that immunological processes responsible for granuloma formation may not be absolutely stage specific.

Urinary glycosaminoglycan excretion in systemic sclerosis subsets compared with normal controls

Urinary glycosaminoglycan (GAG) excretion was studied in 30 patients with established systemic sclerosis and compared with 30 normal controls. There was no significant difference in excretion values in the patient group as a whole, but in the group defined as 'incomplete CREST' urinary GAG values were lower than the group with 'diffuse disease' and controls.