Relationships of the soluble human A,B, and H antigens of blood group A1B individuals

Summary Ouchterlony double diffusion reactions with precipitating antibodies and lectins provide visual evidence that in saliva of A₁B secretor individuals the A and B antigens are predominantly situated on the same molecule, while the H antigen is on a different molecule.     

Localization of human A,B and H isoantigens in Cynomolgus monkey tissues

Summary The presence and distribution of human A, B and H isoantigens were demonstrated in Cynomolgus monkey (Macaca fascicularis) by means of red cell adherence test. Although no human antigens were found on primate erythrocytes, various epithelial tissues revealed the presence of A, B or H antigenic substance. The distribution and localization was similar to that found in human tissues. Majority of specimens from each individual animal possessed only 1 human type isoantigen with the exception of the salivary and sweat glands, where all animals showed the presence of H antigen in addition to other specificity, and of Brunner's gland, where all sections reacted positively also for A antigen.     

Presence of the H blood group antigen on a carcinoembryonic antigen (CEA). Enzymatic transformation of H to A and B specificities]

The carcinoembryonic antigen (CEA-M) was purified from a hepatic metastasis obtained from a blood group O patient with a cancer of the rectum. Using 125I-labelled-CEA and blood group antisera, H specificity was found on the CEA-M; the addition of anti-H to anti-CEA does not modify the binding of labelled-CEA-M to its antibodies (86%), this result leads us to conclude that H and CEA determinants are carried by the same molecule. However the low percentage of binding (30% with 1/10 anti-H) suggests that only a few CEA-M molecules do carry the H antigenic determinant. Finally, glycosyltransferases were used to modify the H specificity into blood group A and B specificities.     

Cloning of the hepatitis B virus genome in Escherichia coli]

The whole genome of the hepatitis B virus (Dane particles) was inserted in vitro in the genome of the bacteriophage lambda gtWES . LAMBDA B. The recombinant DNA molecule was cloned in E. coli. Amplification of the hybrid bacteriophage enables the preparation of large amounts of hepatitis B virus DNA. The possibilities offered by the utilization of this recombinant bacteriophage are discussed.     

Cannflavin A and B, prenylated flavones from Cannabis sativa L

Two novel prenylated flavones, termed Cannflavin A and B, were isolated from the cannabinoid free ethanolic extract of Cannabis sativa L. Both compounds inhibited prostaglandin E2 production by human rheumatoid synovial cells in culture.     

Structures of the venturicidins A and B

Riassunto Con l'uso combinato di metodi chimici, spettroscopici, e di strutturistica chimica diffrattometrica è stato possibile assegnare le strutture I e II alle venturicidine A e B rispettivamente.     

New antibiotics,trichopolyns A and B: Isolation and biological activity

Summary Polypeptide antibiotics, trichopolyns A and B, were isolated from the culture broth ofTrichoderma polysporum (Link ex Pers) Rifai (TMI 60146). Assessment of biological activity of the antibiotics against microorganisms was made.Acknowledgment. We are most grateful to Central Research Division, Takeda Chemical Industry Co. Limited, for determination of antifungal and antibacterial spectra.     

Gonadotrophin-releasing activity of histones H2A and H2B

We report that histones H2A and H2B possess gonadotrophin-releasing activity in vitro and assess the signal transduction pathways involved in these effects. Perifused and incubated rat anterior pituitary (AP) cells were used, and luteinizing hormone (LH) and follicle stimulating hormone (FSH) were measured by RIA. Perifusion of cells with histone H2A (30 μM) or histone H2B (30 μM), markedly stimulated LH release but failed to elicit any FSH response. Cells incubated with 6 or 30 μM histone H2A showed a dose- and time-dependent stimulatory effect on both LH and FSH release which was blocked by 1 μM peptide MB35, an 86–120 amino acid fragment of histone H2A. Incubation of pituitary cells with gonadotrophin-releasing hormone (GnRH) and histones H2A or H2B showed a stimulatory effect on LH and FSH release which was similar to the sum of the separate effects. Trifluoperazine, as well as ethylene glycol bis(b-aminoethyl ether) N,N,N′,N′-tetraacetic acid (EGTA), alone or in the presence of the calcium ionophore A23187, significantly reduced the response of AP cells to histones. Various cyclic adenosine monophosphate (cAMP) enhancers had no effect on histone-stimulated release of gonadotrophins in incubated AP cells. Our results confirm previous evidence that histones may act as hypophysiotrophic signals. Calcium- and diacylglycerol-associated pathways, but not cAMP, appear to participate in these effects. Received 11 August 1997; received after revision 20 January 1998; accepted 26 January 1998     

Cannflavin A and B,prenylated flavones fromCannabis sativa L.

Summary Two novel prenylat flavones, termed Cannflavin A and B, were isolated from the cannabinoid free ethanolic extract ofCannabis sativa L. Both compounds inhibited prostaglandin E₂ production by human rheumatoid synovial cells in culture.This communication is dedicated to the memory of the late Professor J. W. Fairbairn and the late Dr. J. T. Pickens. We are grateful to the Medical Research Council for a project grant and to Ms J. Elliot of King's College London for NMR spectra.     

Acid degradation of erythromycin A and erythromycin B

Zusammenfassung Es wird die Bildung der 8,9-Anhydroerythromycin A und B 6, 9-Hemiketale aus den entsprechenden Erythromycinen mit Essigsäure bewiesen.     

Okinonellins A and B,two novel furanosesterterpenes,which inhibit cell division of fertilized starfish eggs,from the marine spongeSpongionella sp

Cellular and Molecular Life Sciences - Two novel furanosesterterpenes, okinonellins A (1) and B (2), have been isolated from the spongeSpongionella sp. Both compounds inhibit cell division of...     

Mammalian arylsulfatases A and B: relative rates of hydrolysis of artificial substrates

Rodent and bovine arylsulfatase B hydrolyze 4-methylumbelliferyl sulfate (4MUS) 10- to 30-fold more efficiently than arylsulfatase A. Therefore, 4MUS grossly underestimates arylsulfatase A activity in the presence of excess arylsulfatase B.     

Prianicin A and B,nor-sesterterpenoid peroxide antibiotics from red sea sponges

Summary The antibiotic properties of 2 acidic C₂₄H₄₀O₄ nor-sesterterpenoid peroxides, prianicin A (1) and B (2), against gram-positive and gram-negative bacteria, and against fungi are herein described. They are 4–10 times more effective than tetracycline againstbeta hemolytic Streptococcus, but significantly non-effective against a variety of gram-negative bacteria.Acknowledgment. The authors are grateful to Prof. A. Kjaer of the Organic Chemistry Department of the Technical University of Denmark, for his help and fruitful discussions.     

Mammalian arylsulfatases A and B: relative rates of hydrolysis of artificial substrates

Summary Rodent and bovine arylsulfatase B hydrolyze 4-methylumbelliferyl sulfate (4MUS) 10- to 30-fold more efficiently than arylsulfatase A. Therefore, 4MUS grossly underestimates arylsulfatase A activity in the presence of excess arylsulfatase B.     

Candletoxins A and B, 2 new aromatic esters of 12-deoxy-16-hydroxy-phorbol,from the irritant latex of Euphorbia poisonii Pax

Summary 2 new aromatic esters of 12-deoxy-16-hydroxy-phorbol, known as candletoxins A and B, were isolated from the irritant latex of Euphorbia poisonii Pax. Compound A was identified as 12-deoxy-phorbol-13-O-phenylacetate-16-O--methyl-butyrate-20-acetate, and compound B was the C-20 desacetyl analogue.Acknowledgments. F. J. E. is grateful to the Central Research Fund of the University of London for a travel grant to visit West Africa, and R.J.S. is indebted to the Science Research Council for a research studentship.     

Higher oxygen affinity of sheep Hb C compared to Hb A and Hb B

Summary Sheep which have Hb A, synthesize the perinatal Hb C in response to severe tissue hypoxia. It is known that Hb A displays a higher oxygen affinity than Hb B. The results of this study indicate that Hb C exhibits an oxygen affinity and a Bohr effect higher than those of Hb A and Hb B.Part of this work was supported by a grant of Ministero Pubblica Istruzione.     

Milanjilactones A and B,two novel cytotoxic norditerpene dilactones fromPodocarpus milanjianus Rendle

Summary Two new cytotoxic norditerpene dilactones, milanjilactones A(3) and B(4) have been isolated from the stem bark ofPodocarpus milanjianus Rendle and characterized, on the basis of spectroscopic evidence, as 1,2-dehydro derivatives of nagilactones F(1) and G(2).The authors acknowledge the technical assistance of Ms Teresa K. Lightner. Part 11 in the series Potential Antitumor Agents.     

Constituants amers deBrucea amarissima structures des brucéines A,B et C

Summary Evidence is presented for the structures (II a), (II b) and (II c) for the bruceines A, B and C, the bitter principles isolated from the seeds ofBrucea amarissima.

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18ème Communication sur les constituants amers des Simarubacées; 17ème Communication, voir².     

Vidalols A and B,new anti-inflammatory bromophenols from the Caribbean marine red algaVidalia obtusaloba

Chemical studies of the Caribbean red algaVidalia obtusaloba have resulted in the isolation of two new bromophenolic metabolites, vidalols A and B (1, 2). The new compounds were discovered as part of an organized effort to isolate new naturally-occurring anti-inflammatory agents with a focus upon those which may function through the inhibition of phospholipase A₂.     

Methoxyphenylethylamines as substrates for type A and type B monoamine oxidase

Summary 4-Methoxyphenylethylamine was found to be a specific substrate for type B monoamine oxidase (MAO) in rat brain mitochondria, whereas 3,4-dimethoxyphenylethylamine was common for both types of MAO. These results suggest that O-methylation in the para-position increases the preference of the substrate for type B MAO, while a methoxy-group in the meta-position contributes to the substance being a type A substrate.