The pronase resistance of cholesterol-nucleating glycoproteins in human bile

BACKGROUND & AIMS: Many putative pronucleating proteins have been isolated from the biliary concanavalin A (con A)-binding fraction. The pronase resistance of the overall nucleating-promoting activity was almost never taken into consideration. The aim of this study was to identify the major pronase-resistant con A-binding glycoproteins. METHODS: Pronase-treated and -untreated con A-binding glycoproteins were separated on a Superose 12 gel permeation column (Pharmacia, Uppsala, Sweden) and tested in a crystal growth assay. Proteins were identified by amino-terminal sequencing. RESULTS: Con A-binding pronucleating activity eluted in two peaks on the Superose column. This activity was unaltered after pronase treatment. Activity peak I contained too little protein to allow amino-terminal sequencing. In activity peak II, the major pronase-resistant con A-binding glycoproteins were identified as alpha 1-antitrypsin and alpha 1- antichymotrypsin. The 130-kilodalton nucleation promoter was identified as aminopeptidase N, but the full pronase resistance of this protein, reported earlier, was not confirmed. Immunoabsorptive removal of alpha 1-antitrypsin and alpha 1-antichymotrypsin and immunopurification showed that only alpha 1-antichymotrypsin had pronucleating activity. CONCLUSIONS: The pronase resistance of the nucleating-promoting activity of the con A-binding glycoprotein fraction was confirmed. An important part of this activity could be attributed to alpha 1- antichymotrypsin. It is an acute-phase protein, as are many other pronucleating proteins, which might indicate a general mechanism of action in gallstone formation. (Gastroenterology 1996 Jun;110(6):1926-35)     

Morphological variation of layer III pyramidal neurones in the occipitotemporal pathway of the macaque monkey visual cortex

We compared the morphological characteristics of layer III pyramidal neurones in different visual areas of the occipitotemporal cortical 'stream', which processes information related to object recognition in the visual field (including shape, colour and texture). Pyramidal cells were intracellularly injected with Lucifer Yellow in cortical slices cut tangential to the cortical layers, allowing quantitative comparisons of dendritic field morphology, spine density and cell body size between the blobs and interblobs of the primary visual area (V1), the interstripe compartments of the second visual area (V2), the fourth visual area (V4) and cytoarchitectonic area TEO. We found that the tangential dimension of basal dendritic fields of layer III pyramidal neurones increases from caudal to rostral visual areas in the occipitotemporal pathway, such that TEO cells have, on average, dendritic fields spanning an area 5-6 times larger than V1 cells. In addition, the data indicate that V1 cells located within blobs have significantly larger dendritic fields than those of interblob cells. Sholl analysis of dendritic fields demonstrated that pyramidal cells in V4 and TEO are more complex (i.e. exhibit a larger number of branches at comparable distances from the cell body) than cells in V1 or V2. Moreover, this analysis demonstrated that the dendrites of many cells in V1 cluster along specific axes, while this tendency is less marked in extrastriate areas. Most notably, there is a relatively large proportion of neurones with 'morphologically orientation-biased' dendritic fields (i.e. branches tend to cluster along two diametrically opposed directions from the cell body) in the interblobs in V1, as compared with the blobs in V1 and extrastriate areas. Finally, counts of dendritic spines along the length of basal dendrites revealed similar peak spine densities in the blobs and the interblobs of V1 and in the V2 interstripes, but markedly higher spine densities in V4 and TEO. Estimates of the number of dendritic spines on the basal dendritic fields of layer III pyramidal cells indicate that cells in V2 have on average twice as many spines as V1 cells, that V4 cells have 3.8 times as many spines as V1 cells, and that TEO cells have 7.5 times as many spines as V1 cells. These findings suggest the possibility that the complex response properties of neurones in rostral stations in the occipitotemporal pathway may, in part, be attributed to their larger and more complex basal dendritic fields, and to the increase in both number and density of spines on their basal dendrites.      

Presence of the rotavirus antigen in newborn infants at maternity hospitals in Moldavia

Studies conducted on 417 feces samples collected from newborn infants from seven maternity homes revealed the presence of rotavirus in 1.2 to 9.5% of the subjects. The infants get infection during the first 24 to 48 hours of life (1.8%) and the positivity rate reaches a peak the 7th day (9.7%). Enteroviruses were found in 3.4% and enterobacteria in 11.8% of the samples.     

Acute myocardial infarction--a possible complication in polycythemia vera. Case report

A 66-year-old woman with Polycythemia Vera suffered an postero-inferior acute myocardial infarction: this is a relative rare association. The association between primary coronary angioplasty with stent implantation and anti-aggregant and myelosuppressive treatment was followed by important clinical benefits for the patient. To our knowledge, there are rare reports in the literature relating the triad of Polycythemia Vera, acute myocardial infarction and primary coronary angioplasty with stent implantation.