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Embryos from dormant and stratified Fraxinus americana seed were incubated with (S)-2-(14)C-abscisic acid (ABA) under a variety of conditions. Both dormant and stratified embryos rapidly metabolize abscisic acid to phaseic acid, dihydrophaseic acid, and an unidentified polar metabolite apparently derived from dihydrophaseic acid. Although the stratified embryos may have an increased capacity to metabolize abscisic acid, our calculations suggest that such an increased capacity would probably not be physiologically significant.Dormant intact seeds also metabolize (S)-2-(14)C-abscisic acid during stratification at 5 C or incubation at 25 C. The metabolites appear to be similar to those observed in excised embryos although by 12 days of stratification a fourth metabolite is observed. More than 90% of the (14)C-abscisic acid was metabolized after 26 days of stratification at 5 C or after 12 days of incubation at 25 C. Stratification at 5 C leads to the breaking of dormancy while incubation at 25 C does not.

Vallée A., Guillon J.-C., Clouet Marcel, Tinelli R., Le Priol A., Saorine A., Lavault R., Nicolas R. Contribution à l’étude des pyélo-néphrites bovines à Corynebacterium renale. In: Bulletin de l'Académie Vétérinaire de France tome 124 n°10, 1971. pp. 463-469.

Aqueous and phenolic extracts and insoluble residues from smooth biotype 1 strains of Brucella abortus and Brucella melitensis were studied for immunologic and biologic comparison. Brucella differ from enterobacteriaceae in a high glucose content and lack of 3-deoxy-D-mannooctulosonic acid (KDO) in aqueous phases, in a rhamnolipid in insoluble residues, and in the high content of nitrogen in extracts made with acetic acid. Some chemical similarities may exist between Pseudomonas and Brucella. Extracts of Brucella, especially phenol extracts of B. melitensis, induce in adult mice a curable wasting disease. None of these fractions sensitize guinea pigs (as determined by dermal hypersensitivity test), but most brucella fractions are allergens for animals already infected with B. abortus. Most of the differences in biologic behavior and in antibody induction between B. abortus and B. melitensis could be associated with an unidentical distribution of similar compounds among the various fractions. In addition, B. abortus differs from B. melitensis in the lack of both galactosamine and methionine.

Changes in the formation of antibodies to sheep red blood cells (sRBC) in the presence of Brucella extracts was studied in mice whose spleen cells were assayed by the Jerne procedure. Two strains of female mice were employed. Brucella extracts were prepared: (i) by trichloroacetic acid extraction (LPSN), (ii) by phenol extraction (LPS), and (iii) by hot acetic acid hydrolysis (Ps). B. abortus LPSN and B. melitensis LPSN or LPS, administered with sRBC, stimulated the specific response to sRBC, but only at high doses of endotoxins. B. abortus LPSN and B. melitensis LPSN suppressed nonspecific responses against horse red blood cells (hRBC), in contrast to the typical events following administration of Serratia marcescens endotoxin (or endotoxins from other ubiquitous organisms). In CD-1 mice, B. abortus Ps depressed the specific anti-sRBC response. Attempts to presensitize mice with abortus LPSN resulted in a stimulation of the response to sRBC, but pretreatment with B. melitensis LPSN had an inhibitory effect. When injected alone, Brucella endotoxins activated anti-sRBC antibody-forming cells but not anti-hRBC cells. B. abortus Ps was unable to modify the background number of anti-sRBC cells and inhibited the hRBC response. These data suggest (i) that there exists a “common antigen” between Brucella cells and sRBC and (ii) that the so-called primary response to endotoxins from ubiquitous organisms represents a secondary response to already naturally sensitized animals.

Tinelli, Regina (Washington University School of Medicine, St. Louis, Mo.), A. M. Michelson, and Jack L. Strominger . Epimerization of thymidine diphosphate glucose in bacterial extracts. J. Bacteriol. 86: 246–251. 1963.—Extracts of Pasteurella pseudotuberculosis type IV and several other bacteria catalyzed the reversible interconversion of thymidine diphosphate (TDP)- d -glucose and TDP- d -galactose. Moreover, extracts of P. pseudotuberculosis catalyzed the synthesis of TDP- d -glucose from thymidine triphosphate and α- d -glucose-1-phosphate. The limitations of these observations and their possible significance are discussed.

Only in 1969 reliable information about glucagon and its different forms was acquired. Some factors are already known to increase or diminish the production both of pancreatic glucagon (nesidioglucagon) and of enteroglucagon. There are various methods for their study. In the present report some results are dealt with that may be of clinical interest, and the possibility of measuring those two kinds of hormones is pointed out as a diagnostic help in reactive and functional hypoglycemic syndromes. Information about glucagon in clinical medicine, however, is still -- on the whole -- scarce and insufficient to throw light on its several physiological and physiopathological aspects.

Embryos from dormant and stratified Fraxinus americana seed were incubated with (S)-2-(14)C-abscisic acid (ABA) under a variety of conditions. Both dormant and stratified embryos rapidly metabolize abscisic acid to phaseic acid, dihydrophaseic acid, and an unidentified polar metabolite apparently derived from dihydrophaseic acid. Although the stratified embryos may have an increased capacity to metabolize abscisic acid, our calculations suggest that such an increased capacity would probably not be physiologically significant.Dormant intact seeds also metabolize (S)-2-(14)C-abscisic acid during stratification at 5 C or incubation at 25 C. The metabolites appear to be similar to those observed in excised embryos although by 12 days of stratification a fourth metabolite is observed. More than 90% of the (14)C-abscisic acid was metabolized after 26 days of stratification at 5 C or after 12 days of incubation at 25 C. Stratification at 5 C leads to the breaking of dormancy while incubation at 25 C does not.