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1.
Antibodies cross-reactive with 4 major aflatoxins were demonstrated three weeks after immunization of rabbits with an immunogen which was prepared by conjugating aflatoxin B3 to bovine serum albumin. Aflatoxin B3 was first converted to its hemisuccinate before conjugation to the protein. Tritiated aflatoxin B1 (AFB1) was used as the marker ligand both for antibody titer determination as well as for analysis of antibody specificity. Competitive RIA revealed that the antibodies have good cross-reactivity with aflatoxins B1, B2, G1, and G2 when tritiated AFB1 was used as the marker ligand. The concentrations causing 50% inhibition of binding of3H-AFB1 to the antibodies by unlabeled aflatoxins B1, B2, G1, G2 and B3 were found to be 0.25, 3.34, 0.32, 4.0 and 0.53 ng/assay, respectively. The antibodies could be used for simultaneous analysis of aflatoxins B1 and G1, two of the most important toxic metabolites produced byAspergillus flavus andA. parasiticus.  相似文献   

2.
Riassunto La somministrazione dietetica di vitamina B12 e di acido orotico determina un aumento della incorporazione dellal-serina C14 nello RNA solubile del fegato di pulcino carente di B12, mentre non è in grado di influenzare quella dellal-leucina14C e dellal-metionina14C.  相似文献   

3.
In this study, we examined the effect of intracerebroventricular (i.c.v) injection of melatonin and/or ACTH1–10 and ACTH4–10 on [3H]flunitrazepam binding sites in the cerebral cortex of hypophysectomized rats. Hypophysectomy increased the Bmax (maximum number of binding sites) of benzodiazepine (BNZ) receptors for at least 7 days after surgery, without changing KD (dissociation constant). The i.c.v. injection of melatonin to hypophysectomized rats significantly increased Bmax, whereas the same doses of melatonin were ineffective in sham-operated animals. In both cases, KD values were unchanged. The i.c.v injection of ACTH1–10 to hypophysectomized animals significantly increased Bmax, an effect that was enhanced by simultaneous i.c.v. injection of ACTH1–10+melatonin, reaching higher values of Bmax than the i.c.v. injection of these hormones individually. No significant changes in KD values were found after ACTH1–10 and/or melatonin administration. However, the i.c.v. injection of ACTH4–10 to hypophysectomized rats did not change Bmax, although it significantly increased KD values, indicating a decrease in the BNZ binding affinity. Melatonin injection counteracted this effect of ACTH4–10, returning KD to the control value. Moreover, although the lower dose of i.c.v. melatonin used, 10 ng, was unable to modify Bmax of BNZ binding in the ACTH4–10-injected group, the higher dose, 20 ng, significantly increased Bmax. The results suggest that these ACTH-derived peptides can modulate the effect of melatonin on brain benzodiazepine receptors.  相似文献   

4.
Summary Glutamic acid does not, either in small or in large doses, inhibit the degeneration of the medullary sheath of peripheral nerves in rats, induced within 15 days by addition of 0.25% of isoniazid to their diet. The detoxicating effect of glutamic acid, as described byCedrangolo 1, thus only applies to the general toxic symptoms of the acute INH-intoxication, as is the case for vitamins B2, B12, A, E, K, and niacinamide.  相似文献   

5.
The nest cell lining ofHylaeus bisinuatus (Hymenoptera: Colletidae) was shown by high-resolution solidstate [13C]NMR to be composed of lipid polymer and protein. The lipid polymer was shown by reduction and subsequent GC/MS analysis to be comprised of -hydroxy fatty acids (C20, C22, C24 and C26) and fatty alcohols (C16 to C30). The protein portion of the lining had a silk-like amino acid composition.  相似文献   

6.
The composition of the Dufour gland of the antC. scutellaris has been reinvestigated by gas chromatography/mass spectrometry. The major components of the gland are (2E,5E,12Z)-4-oxoheneicosa-2,5,12-trien-1-ol acetate (1a) its 14 and 16 double bond isomers (1b and1c), and the corresponding (Z,Z)-dienes5a and5b, all containing an acetylated C21 chain. The previously proposed structures1d, 1e, and5c, which are based on an homologous acetylated C23 chain, correspond to minor derivatives present in the gland. Traces of acetylated C19 homologs, tentatively identified as1g-1i, have also been found. The Dufour gland contents of the two other EuropeanCrematogaster species have also been studied.C. auberti is very similar toC. scutellaris in producing mainly1a, 1b and1c, together with the same higher and lower homologs, but it lacks the dienic derivatives5, whereasC. sordidula contains essentially the acetylated C19 compounds1g, 1h, and1i, accompanied by acetylated C17 homologs.  相似文献   

7.
Summary The Noetherian surfaceF 4 (3) , which is represented on a plane by a linear 3 system ofC 9(A 1 3 A 2 3 A 3 3 A 4 3 A 5 3 A 6 3 A 7 3 A 8 3 A 9 2 A 10), possesses generally only one linear pencil of elliptic cubics. IfA i (i=1, 2, , 9) are the basis points of aHalphen pencil ofC 9,A 10 is infinitely near toA 9, and in this caseF 4 (3) is a not trivial example of such a surface with two pencils of elliptic cubics.  相似文献   

8.
Summary Adult, male rats bred for over 10 generations on a soy meal-corn-diet had vitamin B12 values of liver and kidney about 10 times lower than the controls. If the deficient ration was supplemented with 5µg/kg of B12, these values were still about 1/5 of the controls. 3 weeks on the deficient diet lowered the B12 levels in the livers and kidneys of previously undepleted rats to about 1/2, and a similar diet containing 0.1% of iodized casein lowered these levels to about 1/3 of the normal values but did not lower the B12-concentration of organs of already deficient rats.Rats bred on the deficient diet and receiving for 1 month a supplement of 30µg/kg of vitamin B12 or the stock diet with a similar B12-content, had normal B12-levels in livers and kidneys.  相似文献   

9.
Zusammenfassung 1,3-unsubstituierte Hydantoine (I) werden in einem 3-Stufenprozess in 1-substituierte Abkömmlinge (IV) übergeführt: Blockierung der Stellung 3 durch Aminomethylierung, gefolgt von N1-Alkylierung mit anschliessender Entfernung der Schutzgruppe durch Hydrolyse.

This paper represents Part V of the seriesSubstitution in the Hydantoin Ring; preceding Part,L. Trippetta, O. O. Orazi, andR. A. Corral, An. Asoc. quím. argent., in press.  相似文献   

10.
Summary Antibody against aflatoxin M1 was obtained after immunization of rabbits with bovine serum albumin-afla M1 oxime conjugate. The antibody has greatest binding efficiency for afla M1, and was less efficient for afla B1. Cross-reaction of antibody with aflatoxin Q1, aflatoxicol, and aflatoxin B2a was weak. Aflatoxin B2, G1, and G2 and afla B1-guanine adduct showed almost no cross-reaction with the antibody. The sensitivity of the binding assay for aflatoxin M1 detection is in the range of 1–10 ng per assay. Detailed methods for the preparation of the conjugate, production of immune serum, and methods for antibody determination are described.Supported by the College of Agricultural and Life Sciences, North Central Regional project NC-129, the University of Wisconsin-Madison, and by Public Health Service research grant number CA 15064 from the National Cancer Institute, NIH.The authors wish to thank Dr R.C. Garner for providing aflatoxin-B-guanine adduct, and Dr Dennis H. Hseih for providing aflatoxicol and aflatoxin Q1.  相似文献   

11.
Summary Investigation of the host-specific toxin complex fromH. sacchari has led to the isolation of 3 isomeric glycosidic components C39H64O22, each active at 2×10–11 moles. The 3 isomers consist of 4 galactose units linked to an aglycone residue C15H24O2.Acknowledgments. The Boyce Thompson-Cornell group thanks J.F. Rissler, University of Maryland, A.K. Bose, Stevens Institute of Technology, R. Barker and A. Serriani, Cornell University, and C. Grinnalds and J. Golay, Boyce Thompson Institute for help with various aspects of this work. Supported in part by a grant to V.M. from the US Department of Agriculture (8100720). The Zürich group thanks Dr G.A. Strobel, Department of Botany and Microbiology, Montana State University, Bozeman, for supplying a potent toxin-producing strain (M 36), a susceptible clone of sugarcane (51 NG 97), and a reference sample of helminthosporoside, Dr. K. Hostettmann and Mme M. Hostettmann-Kaldas, Pharmazeutisches Institut ETH Zürich, for assistance in developing the DCC separation and Sandoz A.G., Basel, for financial support.  相似文献   

12.
Zusammenfassung Es wird eine neue Methode vorgeschlagen, Acetaldehyd, Propionaldehyd und Butyraldehyd in Gegenwart von CH4, C2H6, C3H8, C2H4, C3H6, C2H2, CO2, CO, N2, H2 und O2 quantitativ zu bestimmen. Die Methode besteht darin, das Gasgemenge mit Hilfe eines Orsatschen Apparates durch eine bei 20°C gesättigte, Chromtrioxyd und Schwefelsäure enthaltende Natriumsulfatlösung zu schicken, welche die oben genannten Aldehyde selektiv absorbiert.  相似文献   

13.
Summary The epicuticular wax of rice, varietyRibe, comprised n-alkanes, esters, aldehydes and free alcohols. The nalkanes contained 4 major chain lengths, C27, C29, C31 and C33. Triacontanal and dotriacontanal were the major aldehydes. Octacosanol comprised 89% of the free alcohols. The esters were mainly esters of C16 to C24 acids with C22 to C30 alcohols.This research was supported by the Consiglio Nazionale delle Ricerche, Rome.  相似文献   

14.
Summary The active transport of blasticidin S into the cells ofBacillus cereus was significantly inhibited by the addition of detoxin D or poisons of energy metabolism.The authors are grateful to Prof. M. Matsuhashi of our Institute for his valuable advice and to Dr I. Yamaguchi, Institute of Physical and Chemical Research, for the gift of labeled blasticidin S. This work is supported in part by a grant from the Ministry of Education, Science and Culture, Government of Japan.This is Part VII of Studies on Detoxin Complex, the Selective Anatagonists of Blasticidin S. For Part VI, see the preceding report.  相似文献   

15.
Summary The quantitative acidimetric investigation (Bjerrum's method) of CuI coordination reactions in homogeneous aqueous medium is feasible by application of the easily accessible, well crystallized stable complex Cu(CH3CN)4ClO4 in 0.1 to 1 molar CH3CN aq., the stability of particles present in the system CuI, CH3CN, H2O being previously established polarographically. The advantage of the new acidimetric method lies in the possibility of investigating CuI in absence of CuII.  相似文献   

16.
Summary The present communication deals with the isolation of acetyl salicylic acid (aspirin) complexes with Bi+3, Zn+2 and UO 2 +2 . The characterization of 12 complexes have been carried out with the help of conductometric, pH metric, elemental analysis and IR spectral studies. Spectrophotometric studies in case of UO 2 +2 (the only colored complex) in range of 4.2 to 5.5 pH show absorption at 490 nm and complex obey Beers Law at the concentration range of 0.01 M to 0.1 M.  相似文献   

17.
Zusammenfassung Die Struktur eines durch säurekatalytische Isomerisation von Ambreinolid entstehenden tricyclischen Ketons C17H26O wurde aufgeklärt.

Therpenes III.

Part II,G. Büchi andR. E. Erickson, J. Amer. chem. Soc.76, 3493 (1954).  相似文献   

18.
Summary Protoplasts derived fromAspergillus flavus are shown to be capable of synthesizing aflatoxins when incubated in a chemically defined medium.14C-Acetate and14C-Versicolorin A, added to protoplasts from 3-day-old mycelium, are incorporated into aflatoxin B1.  相似文献   

19.
Zusammenfassung Die Struktur des Kondensations-produktes aus Anthranilsäure und S-Methyl-2-thiohydantoin, bzw. aus Anthranilsäuremethylester und N-Cyanglycinäthylester5 wurde als die eines 2,5-(1 H, 3 H) Imidazo(2,1-b) chinazolindions bewiesen.

Part X. Hydantoins, thiohydantoins and glycocyamidines. Part IX.K. Lempert, Chem. Ber.,95, 1066 (1962).  相似文献   

20.
Zusammenfassung Aflatoxin B1 hemmt den Einbau von 1-14C-Azetat in die Lipide der menschlichen Haut. Wird aber3H-Azetyl-CoA als Vorstufe für den Lipideinbau verwendet, so kommt es zu keiner merklichen Hemmung. Die Azetataktivierung scheint somit die wichtigste, vom Toxin beeinflussbare Stufe der Lipidsynthese zu sein.  相似文献   

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