On the distribution of plasma L-asparaginase

Summary The guinea-pig,Cavia porcellus, is unusual in possessing plasma L-asparaginase, an enzyme with anti-tumor activity. 21 additional species have been examined as to the presence of this enzyme: the results confirm and extend its remarkably limited species distribution.This work was supported in part by grant GM/CA 25378 from the National Institute of General Medical Sciences, National Institutes of Health.We are grateful to dr Hanna Hensch, Philadelphia Zoological Garden, and Ms Joan Whitla and Dr Richard J. Montali, National Zoological Park/Smithsonian Institution, for samples of frozen serum.To whom correspondence should be addressed.     

On the distribution of plasma L-asparaginase

The guinea-pig, Cavia porcellus, is unusual in possessing plasma L-asparaginase, an enzyme with anti-tumor activity, 21 additional species have been examined as to the presence of this enzyme: the results confirm and extend its remarkably limited species distribution.     

On the distribution of phytoecdysteroids in plants

The occurrence and levels of phytoecdysteroids in the seeds and other parts of plants grown from the seeds of 180 randomly selected plant species were assessed and compared. Ecdysteroids are frequently detectable in leaves and flowers, but less so in stems, roots and seeds. The seeds of 290 species were assessed for the presence of hydrolysable ecdysteroid conjugates. Low levels of conjugates were detected in a significant number of species, large amounts being present only when levels of free ecdysteroids were high. Individual plants of Arabidopsis thaliana were assessed for the presence of phytoecdysteroids. While plants of this species are generally ecdysteroid negative, individual plants in the population accumulate low levels of ecdysteroids. Extracts of seeds of 50 "ecdysteroid-negative" species were concentrated and partially purified to determine if they possess ecdysteroids at levels below the usual detection levels. Ecdysteroids were detectable by radioimmunoassay in almost all of these concentrated samples. Thus, all lines of evidence point to the conclusion that all species of plants have the capacity to produce at least low levels of phytoecdysteroids. This has important implications for the protection of crop species through enhancing ecdysteroid levels by breeding/genetic modification strategies. Received 2 April 2001; received after revision 4 May 2001; accepted 22 May 2001     

Chemical composition and distribution pattern of crystalline inorganic components in Japanese gymnosperms

Summary It was found that the distribution pattern of calcium oxalate monohydrate present in the leaves of gymnosperms growing in Japan is classified into 2 groups by the technique of the low-temperature plasma ashing method for biological tissues.Acknowledgment. The author expresses his best thanks to the staff of the Koishikawa Botanical Garden, University of Tokyo, for the donation of valuable plant materials for the present work.     

Alternative exon usage selectively determines both tissue distribution and subcellular localization of the acyl-CoA thioesterase 7 gene products

Acyl-CoA thioesterases (ACOTs) catalyze the hydrolysis of acyl-CoAs to free fatty acids and coenzyme A. Recent studies have demonstrated that one gene named Acot7, reported to be mainly expressed in brain and testis, is transcribed in several different isoforms by alternative usage of first exons. Strongly decreased levels of ACOT7 activity and protein in both mitochondria and cytosol was reported in patients diagnosed with fatty acid oxidation defects, linking ACOT7 function to regulation of fatty acid oxidation in other tissues. In this study, we have identified five possible first exons in mouse Acot7 (Acot7a–e) and show that all five first exons are transcribed in a tissue-specific manner. Taken together, these data show that the Acot7 gene is expressed as multiple isoforms in a tissue-specific manner, and that expression in tissues other than brain and testis is likely to play important roles in fatty acid metabolism. Received 5 February 2007: received after revision 3 April 2007; accepted 19 April 2007     

On the distribution in brain of monoamines and of enzymes responsible for their formation

Zusammenfassung Im menschlichen Gehirn kommen grosse Mengen von 3-Hydroxytyramin im Nucleus Caudatus und dem Putamen vor.Injektion von 3,4-Dihydroxyphenylalanin in Kaninchen bringt eine schnelle Akkumulation von 3-Hydroxytyramin in den Gehirnteilen, die reich an Katecholaminen sind, zustande. Die Fähigkeit das akkumulierte 3-Hydroxytyramin abzubauen scheint im ganzen Gehirn dieselbe zu sein.Hemmungsversuche und Aktivitätsuntersuchungen der Fermente in verschiedenen Gehirnteilenin vitro sprechen dafür, dass 5-Hydroxytryptophan und 3,4-Dihydroxyphenylalanin von einem und demselben Ferment decarboxyliert werden.     

Pressure acclimation of the eel and liver membrane composition

Homeoviscous adaptation of membrane fluidity is known to exist in fish living at great depths. Is this adaptation also present in fish living near the surface but experimentally acclimated to high pressure? The composition of mitochondria-rich fractions extracted from the livers of eels acclimated for 15 days at 101 ATA was determined. The results show that pressure induced a significant increase (+100%) of total phospholipids (PL) and cholesterol without a change in their ratio. The increase of PL content was accompanied by a decrease in phosphatidylcholine in favour of phosphatidyl ethanolamine which, due to its preference for the H₁₁ form, is able to compensate for the loss in fluidity induced by pressure.     

7a-Aza-B-homo[7a, 7-d]tetrazole analogues of progesterone and testosterone

Summary The tetrazole analogues of progesterone and testosterone, namely, 7a-aza-B-homo-4-pregneno[7a, 7-d]tetrazole-3,20-dione (5) and 3-oxo-7a-aza-B-homo-4-androsteno[7a, 7-d]tetrazol-17-yl acetate (8), have been prepared which are worthy of biological testing.Part XLIII in the series Steroids and Related Studies. For Part XLII see H. Singh and K.K. Bhutani, Indian J. Chem. in press.     

Carbohydrate composition of the human cataractous lenses

Summary Specific chemical assays, including carbohydrate, hexosamines and hexuronic acid, were determined on the lens insoluble albumoid. It was noticed that the carbohydrate composition varies with age. The significance of carbohydrate in the lens in discussed.This work was supported by the College of Medicine of the University of Lagos, and financed by the British Council. The work was undertaken at the Department of Chemistry and Applied Chemistry, University of Salford, Salford (England).Special thanks are expressed to Dr L. R. Croft and Prof. G. I. Phillip for their help, support and encouragement throughout this study.     

Tensile strength and chemical composition of the middle lamella of the flax fibre

Zusammenfassung Es wurde die Zugkraft nasser Flachsfasern nach Behandlung mit verschiedenen Chemikalien geprüft. Es wurde gefunden, daß die Mittellamelle der Flachsfaser verschiedene miteinander verbundene Systeme enthält, nämlich Pektin, Lignin und eine im Oxalat unlös iche alkaliempfindliche Komponente.     

Oxygen isotopic composition of fogs and rains from the North Atlantic

Riassunto È stata determinata la composizione isotopica dell'ossigeno in campioni di nebbia e di pioggia raccolti principalmente nell'Atlantico nord-occidentale. I risultati mostrano che la nebbia deriva, almeno in buona parte dei casi, da condensazioni parziali di vapor d'acqua in equilibrio con l'acqua oceanica. Il contenuto in O¹⁸ delle piogge misurate varia in relazione alla durata ed alla latitudine.