In a recent series of papers, Miller and co-workers were able to show that His(pi-Me)-based, terminally protected peptides are potent catalysts of the asymmetric acyl transfer reaction, useful for ...the kinetic resolution of alcohols. In a structure-supporting solvent, one of the most active compounds, an Aib-containing tetrapeptide, is folded in a doubly intramolecularly H-bonded beta-hairpin motif incorporating a type-II' beta-turn conformation. In this work, we have expanded the study of the Miller tetrapeptide by examining a set of analogues and shorter sequences (dipeptide amides), characterized by chiral C(alpha)-tetrasubstituted alpha-amino acids of diverging bulkiness and optical configuration. Peptide synthesis in solution, conformational analysis by FT-IR absorption and (1)H NMR techniques, and screening of catalytic activity as well have been performed. Our results confirm the close relationship between the beta-hairpin 3D-structure and the catalytic activity of the peptides. A tetrapeptide analogue slightly more selective than the Miller compound has been found. However, the terminally protected, industrially more appealing, dipeptide amides are poorly effective.
Teats lesions caused by parapox virus occurred in a dairy cattle farm. In the present paper, the clinical course of the disease, the lesions and the laboratory investigation are described. The ...infection overspread entirely to milking cows during four weeks since the time of first lesion outbreak. During a period of about two months, we observed a clinical recovery from lesions on the teats; moreover, we did not observe any difference for quantity and quality of milk yield
In seguito all'isolamento di parapox virus in corso di telite in bovini da latte, si e' voluto descrivere l'evoluzione dell'infezione con particolare riferimento alla tipologia di lesioni riscontrate, agli accertamenti diagnostici utilizzati e agli interventi igienico-sanitari adottati. L'infezione si e' diffusa a tutte le bovine in lattazione in un periodo di quattro settimane dalla prima manifestazione delle lesioni cutanee. Nell'arco di circa 2 mesi, si e' osservata la guarigione clinica dei capezzoli colpiti dalle lesioni e durante tale periodo non si sono riscontrate variazioni nella quantita' e qualita' del latte prodotto
The AA report of an episode characterised by high mortality in canary birds belonging to a private aviary. Sudden episodes of mortality in the nestling birds, characterised by anorexia, depression ...and swelling of the abdomen which often appeared reddish, resulted in mortality of 90% of the young birds. Routine bacteriological and parasitological investigations resulted negative. Virological investigations performed on primary chick embryo liver and fibroblast cells and on the MDCC-MSB1 cell line did not result in the isolation of any virus. On the contrary, circovirus-like particles could be identified in negative contrast electron microscopy from pooled organ samples
Gli AA descrivono un episodio caratterizzato da elevata mortalita' in canarini facenti parte di un gruppo amatoriale. Improvvisi episodi di mortalita' nei novelli, caratterizzati da anoressia, depressione e rigonfiamento dell'addome, che spesso appariva arrossato, esitavano in mortalita' nel 90% dei soggetti colpiti. Gli esami batteriologici e parassitologici di routine sono risultati negativi. Gli esami virologici condotti su cellule primarie di fegato e fibroblasti di embrione di pollo e su cellule in linea continua MDCC-MSB1 non hanno permesso l'isolamento di alcun virus. Al contrario, l'esame al microscopio elettronico in colorazione negativa di un pool di organi ha permesso di osservare particelle circovirus-like
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