Weather patterns and asthma epidemics in New York City and New Orleans,U.S.A.

Twenty-five years of data on asthmatic attacks in New Orleans (covering approximately 170,000 asthma attacks) have been analyzed to identify asthma epidemic days, defined as days on which an unusually high number of asthmatic individuals had attacks. Similar data covering three years was obtained for New York City. A preliminary examination of detailed meteoroligical data revealed a consistent meteorological pattern preceding and associated with such asthma epidemic days which consisted of a cold front preceding an asthma epidemic by one to three days followed by a high pressure system. The significance of these meteorological findings and their relationship to other environmental agents such as natural or man-made atmospheric pollutants that are likely to be associated with asthma attacks will be discussed.Presented at the Eighth International Congress of Biometeorology, 9–14 September 1979, Shefayim, Israel.     

New reagents, reactions, and peptidomimetics for drug design.

It has been a major focus in our laboratories to prepare novel reagents and peptidomimetic structures for drug design. We have designed and prepared novel guanidinylation reagents that can be employed in solution or as solid phase reagents. We and others have utilized the reagent 3-(diethoxyphosphoryloxy)-1,2,3-benzotriazin-4(3H)-one (DEPBT) for amide bond formation to couple sterically hindered structures. These couplings proceed with remarkably strong resistance to racemization. In the area of peptidomimetics, we have incorporated novel building blocks to create biologically active compounds. These building blocks include thioether and alkylamine bridges, beta-methylated, and beta,beta-dimethylated amino acid residues. These mimetic structures have been incorporated into specific target molecules such as opioids to obtain cyclic peptidomimetics with potent and selective biological activity.     

Epsilon-alkyllysinase. New assay method, purification, and biological significance

?-Alkyllysinase (EC 1.5.3.4.) has been solubilized and purified approximately 15-fold from rat kidney. Flavin adenine dinucleotide stimulated the partially purified enzyme preparation. The enzyme produces an equimolar amount of l-lysine and formaldehyde from ?-N-monomethyl-l-lysine while consuming half a mole of oxygen. Based on the determination of radioactive formaldehyde from ?-N-mono[¹⁴C]methyl-lysine a new, highly sensitive assay method has been developed. All available evidence indicates that ?-alkyllysinase is identical to histone demethylase which has been previously reported to be rich in rat kidney mitochondria. The ?-alkyllysinase activity in the liver and kidney of a young rat are relatively low, and reaches the adult level during or before puberty. On the other hand, protein methylase III, which methylates histones using S-adenosyl-l-methionine as methyl donor, is high in the young rat liver and kidney, and decreases to the adult level in a pattern opposing that of ?-alkyllysinase. This opposing pattern of change of protein methylase III and ?-alkyllysinase activity is also found in fast-growing Novikoff hepatoma: While ?-alkyllysinase activity is practically nil in the hepatoma, protein methylase III is very high.     

A New Toxic Substance,Teleocidin, Produced by Streptomyces.

In the course of studies on the screening of specific toxic substances produced by Streptomyces against aquatic organisms, it was recognised that a newly isolated Streptmyces, 2A 1563, which was considered to be a variant species of Streptomyces mediocidicus produces a new toxic substance, Teleocidin. Teleocidin was isolated as a white powder resembling crystals with a crystal appearance from the methanol extracts of the cultured mycellium, and showed a specific toxic action toward Japanese killifish and mice, but did not exhibit any inhibition against microorganisms.     

New antibiotics produced by streptoverticillium orinoci,n. sp.

Summary Three new antibiotics, neoantimycin, neaureothin and ochramycin have been isolated from Streptoverticillium orinoci. The systematic position of the organism is discussed.Neoantimycin is related to the antimycin antibiotics group; neoaureothin shows some similarity with aureothin. Ochramycin is an amphoteric compound containing in its molecule an octaene chromophore.The first two antibiotics show a slight antifungal activity only. Ochramycin is active against gram +ve, but not against gram -ve bacteria; its activity against yeasts and fungi is very slight.Toxicity data are reported; no therapeutical effectiveness has been observed in experimental infections in mice.     

New versatile, elastomeric, degradable polymeric materials for medicine.

The present investigation was focused on the cell compatibility of recently developed biodegradable polyesterurethane-foam (DegraPol-foam) to chondrocytes and osteoblasts. Both chondrocytes and osteoblasts, isolated from adult male rats, exhibited relatively high cell adhesion on DegraPol-foam. Scanning electron microscopy (SEM) showed that cells grew on the surface and into the open cell pores of the foam. Morphologically, cells found on the surface of the foam exhibited a flat cell appearance and built a confluent cell multilayer. In contrast, inside the foams cell showed rounded morphology building cell aggregates and cell islets. In addition, chondrocytes and osteoblasts proliferated on the DegraPol-foam and preserved their phenotype for up to 2 weeks. During degradation of these polymers, small crystalline particles of short-chain poly[(R)-3-hydroxybutyric acid] (Mn approximately 2300) (PHB-P) and lysine methyl ester are released. Therefore, lysine methyl ester and PHB-P, as possible degradation products of the polymer, are investigated here for their effects on macrophages and osteoblasts. Results obtained in the present study clearly indicate that macrophages and, to a lesser degree, osteoblasts have the ability to take up (phagocytose) PHB-P. At low concentrations, particles of PHB failed to induce cytotoxic effects or to activate macrophages. Osteoblasts showed only limited PHB-P phagocytosis and no signs of any cellular damage. At high concentrations of PHB-P, the cell viability of macrophages and to a lesser extent of osteoblasts was affected.