From an overall point of view, the epidemiological situation of influenza C virus infections in western Europe is hardly known. In some countries like Spain, no epidemiological survey has been carried out to determine whether influenza C virus does or does not circulate and cause infection in the considered geographical area. We thus decided to perform such a study. A total of 191 serum samples was collected from people (from 1.5 to 80 years old) living in Spain in October 1990. These sera were tested for the presence of antibodies to influenza C virus by hemagglutination-inhibition (HI) tests. Significant HI activity was found in 59.3 to 64.9% of the 191 tested sera and titres ranged from 20 to 320. The high prevalence of antibody as well as the highly significant titres indicate an intense circulation of influenza C virus in Spain. A significant difference was found between children/teenagers and adults.

Rimantadine-resistant and -sensitive influenza A variants were assayed for their sialidase (neuraminidase, EC 3.2.1.18) activity. The kinetic parameters determined (pH optimum, stability against different pH values, thermal stability, activity on methylumbelliferyl- α-D-N-acetylneuraminic acid, N-acetylneuraminyl-lactose, fetuin and bovine submandibular gland mucin as substrates, K(m) with the former substrate, inhibition by two competitive inhibitors, and behavior towards amantadine) revealed the same results for both variants of the virus. Thus, it can be deduced that resistance to rimantadine does not influence the sialidase activity of influenza A virus.

Two forms, I and II, of an acid ß-galactosidase from rabbit spleen were separated by DEAE-cellulose chromatography and then characterized. Both forms of the enzyme showed different heat-stability (form I being heat-labile and form II heat-stable), and different pi (6.7 for form I and 5.3 and 6.7 for form II). Their gel filtration patterns were also different: form I was resolved in a single peak of mol. wt. 75,000, whereas form II was resolved in one or two peaks of mol. wt. 120,000 and greater than 200,000, depending on the pH of elution. However, both forms had similar pH stability and behavior toward α-methyl-ß-D-galactopyranoside, α-methyl-ß-D-glucopyranoside, urea and KC1. Differences in pH optima, optimal temperature and K(m) values were not marked.

During cocaine exposure, the liver undergoes significant morphological and biochemical changes. We report here changes in the ganglioside pattern of rat liver after repeated administration (over 5 hours, one injection per hour) of a moderate dose of cocaine (10 mg/kg body weight). Cocaine exposure results in an accumulation of more complex gangliosides (GM1, GD1a, GD1b, GT1b and GQ1b) and a reduction of precursors (GM3, GM2, GD3 and GD2). Our results suggest that ganglioside biosynthesis could be affected by an alteration of vesicular transport from cis- to trans-Golgi cisternae produced either by cocaine itself or by some product of cocaine metabolism.