5-(Hydroxyimino)-4-methoxy-2-(pivaloylimino)thiazolidine-3-acetamide,a reduced nitroheterocyclic derivative with potent schistosomicidal properties

Summary The synthesis and antischistosome properties of 5-(hydroxyimino)-4-methoxy-2-(pivaloylimino)thiazolidine-3-acetamide (1) are described. The compound was prepared by reduction of the nitrothiazoline (2) with stannous chloride in methanol, and represents the first example of a reduced nitroheterocyclic compound showing potent schistosomicidal properties. The possible relationship of compounds such as1 to the as yet unidentified reduced active but toxic entities formed in vivo from nitroheterocyclics like metronidazole is discussed.Acknowledgments. The authors are grateful to Dr A. J. Everett and his staff for the physical chemistry measurements, and to Mr G. Dickerson for the antischistosome testing.     

Selected decrease of haemocytes of the freshwater snailPlanorbarius corneus (L.) (Gastropoda,Pulmonata) after bacteria injection

Summary The decrease of haemolymph phagocytic cells (SH) inPlanorbarius corneus after bacterial injection seems to be mediated by humoral factor(s) released into the haemolymph. SH show different adhesiveness in vitro in the presence of bacterial metabolic products.     

Antibacterial activity in the egg mass of a sea hare

Summary The eggs of a sea hare,Aplysia kurodai, contained antibacterial factors which probably play a role in the defense of eggs against bacterial infection. The active factors were composed of several heat-labile proteins, unrelated to lysozyme, and were produced in the albumen gland.     

1-(Substituted)benzyl-5-aminoimidazole-4-carboxamides are potent orally active inhibitors ofTrypanosoma cruzi in mice

Summary 1-(Substituted)benzyl-5-aminoimidazole-4-carboxamides are potent orally active inhibitors ofTrypanosoma cruzi infections in mice. The most active compounds are the 1-(4-chlorobenzyl)- and 1-(3,4-dichlorobenzyl)-analogs (L-153,094 [2] and L-153,153 [4], resp.) which are approximately 7-fold more potent upon oral administration than nifurtimox (Lampit) in suppressing parasite levels in the blood of mice with acuteTrypanosoma cruzi infections.     

(E)-3-tridecen-2-one,an antibiotic from the interdigital glands of black-tailed deerOdocoileus hemionus columbianus

(E)-3-tridecen-2-one, the major volatile component of interdigital gland extracts from the black-tailed deer,Odocoileus hemionus columbianus, inhibited the growth of gram-positive bacteria and fungi. The bacteria,Propionibacterium acnes, and the fungi,Trichophyton mentagrophytes had a minimum inhibitory concentration (MIC) of 12.5 g/mL and 25 g/mL, respectively.     

Studies onHolothuria polii (Echinodermata) antibacterial proteins. I. Evidence for and activity of a coelomocyte lysozyme

Summary Lysozyme activity has been detected in coelomocyte lysate of the echinodermHolothuria polii. The bacteriolytic reaction was stable when the lysate was heated in acidic buffer but heat-labile in alkaline medium. An incubation temperature of 35°C, acidic pH values (5.2 and 6.2) and an ionic strength of 0.175 were found to be the best conditions for the coelomocyte enzymatic activity. A low level of lysozyme was also evidenced in cell-free coelomic fluid where it could represent a basal defense level of bacteriolytic molecules released by the coelomocytes.Acknowledgments. This work was supported in part by a grant from MRES (C. C.). The authors thank M. Lasségues and F. Lassalles for their help and criticism.     

2-Amino-6-[(1'R,2'S)-1',2'-dihydroxypropyl]-3-methyl-pterin-4-one,a biologically active metabolite from the anthozoanAstroides calycularis Pallas

Summary 2-Amino-6-[(1'R,2'S)-1',2'-dihydroxypropyl]-3-methyl-pterin-4-one (1) has been isolated from the marine anthozoanAstroides calycularis; its structure was illustrated by spectral analyses including 2D-NMR and by partial synthesis.1 appears to possess cell-growth inhibiting activity.29 December 1986Work supported by C.N.R. (Progetto Finalizzato Chimica Fine e Secondaria) and by Ministero Pubblica Istruzione Italy. — Acknowledgments. Mass spectral data were provided by Servizio di Spettrometria di massa del C.N.R. e dell'Università di Napoli. The assistance of the staff is gratefully appreciated. Finally we would like to thank Prof. C. Pietropaolo for supplying chick embryo fibroblasts.     

(Z)-1,17-diaminooctadec-9-ene,a novel aliphatic diamine from coccinellidae

Summary The isolation and structure determination of (Z)-1,17-diaminooctadec-9-ene from several species of Coccinellidae is reported.Maître de Recherches du Fonds National de la Recherche Scientifique.We gratefully acknowledge the Fonds National de la Recherche Scientifique for financial support. We express our sincere thanks to Professor K. S. Hagen for a generous gift ofH. leis conformis.     

Protective effect of N-(2-propynyl)-2-(5-benzyloxy-indolyl) methylamine (PF9601N) on mitochondrial permeability transition

PF9601N, N-(2-propynyl)-2-(5-benzyloxy-indolyl) methylamine, an monoamine oxidase (MAO) B inhibitor, has shown neuroprotective properties against dopaminergic toxins. To elucidate the mechanisms involved in this protection, the effect of PF9601N on mitochondria was assessed. PF9601N prevents mitochondrial swelling, drop in the electrical potential and oxidation of sulfhydryl groups, glutathione and pyridine nucleotides induced by Ca²⁺. These observations demonstrate the protective effect of PF9601N on the induction of mitochondrial permeability transition. This protection is due to the interaction of the secondary protonated amino group in the molecule with pore-forming structures and to its antioxidant property, rather than to inhibition of MAO B activity. PF9601N also prevents the release of cytochrome c from mitochondria, suggesting its potential inhibitory effect on mitochondria-mediated apoptosis. The low IC⁵⁰ value for this inhibition, in comparison with deprenyl, make it a more efficient compound than propargylamines and other amines in protecting the bioenergetic functions of mitochondria. Received 9 March 2006; received after revision 10 April 2006; accepted 21 April 2006     

Dual modes of 5-(N-ethyl-N-isopropyl)amiloride modulation of apical dipeptide uptake in the human small intestinal epithelial cell line Caco-2

Selective pharmacological Na⁺/H⁺ exchange (NHE) inhibitors were used to identify functional NHE isoforms in human small intestinal enterocytes (Caco-2) and to distinguish between direct and indirect effects on transport via the intestinal di/tripeptide transporter hPepT1. The relative potencies of these inhibitors to inhibit ²²Na⁺ influx identifies NHE3 and NHE1 as the apical and basolateral NHE isoforms. The Na⁺-dependent (NHE3-sensitive) component of apical dipeptide ([¹⁴C] Gly-Sar) uptake was inhibited by the selective NHE inhibitors with the same order of potency observed for inhibition of apical ²²Na⁺ uptake. However, 5-(N-ethyl-N-isopropyl) amiloride (EIPA) also reduced [¹⁴C]Gly-Sar uptake in the absence of Na⁺ and this inhibition was concentration and pH (maximal at pH 5.5) dependent. NHE3 inhibition by S1611 and S3226 modulates dipeptide uptake indirectly by reducing the transapical driving force (H⁺ electrochemical gradient). EIPA (at 100 μM) has similar effects, but at higher concentrations (>200 μM) also has direct inhibitory effects on hPepT1.Received 28 February 2005; received after revision 20 April 2005; accepted 20 May 2005     

Identification and biological significance of 4-methyl-3Z,5-hexadienoic acid produced by males of the gall-forming tephritidsUrophora cardui (L.) andUrophora stylata (Fab.) (Diptera: Tephritidae)

Summary A new natural substance has been identified in the rectal ampullae of gall-forming fruit flies. The substance was found to be the only volatile compound in the rectal ampulla of maleUrophora cardui andUrophora stylata. GC-MS methods were used to characterize its structure as 4-methyl-3Z,5-hexadienoic acid. Physiological parameters such as the amount of the acid at different ages and under different conditions were investigated. The biological significance of the new volatile as an arresting pheromone was tested in several bioassays. The arrestant function could not be established, but the results gave hints of a territorial function between conspecific males. The results are discussed with respect to gland morphology and predictions of communication models among fruit flies.     

Long-term depression of two primary immune responses induced by a single dose of 5-(3,3-dimethyl-1-triazeno)-imidazole-4-carboxamide (DTIC)

Summary 2 primary immune responses (anti-SRBC antibody response and allograft rejection) have been tested in mice at various time intervals after single doses of either DTIC or cyclophosphamide. The DTIC-induced immunodepression proved to be extremely long-lasting, being still detectable after 2 months.This work was supported by Project NO1-CB 64054 of the U.S.-Italy Cooperative Science Program.     

(S)-(+)-4,4,4-Trifluoro-3-(indole-3-)butyric acid,a novel fluorinated plant growth regulator

Racemic 4,4,4-trifluoro-3-(indole-3-)butyric acid (TFIBA) has been synthesized and shown to inhibitAvena coleoptile elongation. (S)-(+)-TFIBA (fig. 1), which was prepared by an enzymatic method and markedly promotes root growth of Chinese cabbage, lettuce and rice plants, is a novel fluorinated plant growth regulator. Activity of the (S)-(+)-enantiomer of TFIBA was 10-fold greater than that of the (R)-(–)-enantiomer in the first two plant species and 5-fold greater in rice.     

Preliminary observations of a bacteriophage infectingXenorhabdus luminescens (Enterobacteriaceae)

A bacteriophage infective toXenorhabdus luminescens, a bacterial symbiont of heterorhabditid nematodes, was recovered from insects that supported poor nematode development. Plaque tests showed the phage particles to be infective only to primary and not secondary colonies ofX. luminescens. The phage was not infective toX. nenatophilus primaries or secondaries. The bacteriophage particles ranged 80–90 nm in length, with the head ranging from 40 to 50 nm in diameter. Restriction analysis was performed on isolated bacteriophage DNA. This first report of a bacteriophage fromXenorhabdus species has pratical implications since it could be detrimental to cultures ofHeterorhabditis nematodes that are being produced throughout the world for the biological control of insects.     

The C4-dicarboxylate transport system ofRhizobium meliloti and its role in nitrogen fixation during symbiosis with alfalfa (Medicago sativa)

TheRhizobium meliloti C₄-dicarboxylate transport (Dct) system is essential for an effective symbiosis with alfalfa plants. C₄-dicarboxylates are the major carbon source taken up by bacteroids. Genetic analysis of Dct^– mutant strains led to the isolation of thedct carrier genedctA and the regulatory genesdctB anddctD. The carrier genedctA is regulated in free-living cells by the alternative sigma factor RpoN and the two-component regulatory system DctB/D. In addition, DctA is involved in its own regulation, possibly by interacting with DctB. In bacteroids, besides the DctB/DctD system an additional symbiotic activator is thought to be involved indctA expression. Further regulation ofdctA in the free-living state is reflected by diauxic growth of rhizobia, with succinate being the preferred carbon source. The tight coupling of C₄-dicarboxylate transport and nitrogen fixation is revealed by a reduced level of C₄-dicarboxylate transport in nitrogenase negative bacteroids.     

Flavonoid profiles of certain species ofRhynchosia of the family Leguminosae (Fabaceae)

Summary A survey of seventy naturally occurring populations ofRhynchosia representing seven species of different subgenera revealed the occurrence of C-glycosides, O-glycosides, prenylated flavonoids and aglycones.Rhynchosia albiflora (R. cyanosperma) differs in gross morphological features and seed coat color and in its flavonoid composition from the other representative species ofRhynchosia.Acknowledgments. P. Ramachandraiah is grateful to U.G.C., New Delhi, for financial assistance.     

Effects of TA [4-ethoxy-1-(p-tolyl)-s-triazine-2,6-(1H, 3H)-dione] on growth,antheridium differentiation and gibberellin uptake of gametophytes ofAnemia phyllitidis L. Sw.

Summary Synergistic effects of TA on gibberellin-dependent reactions in spermatophytes are not detectable in gametophytes of the fernAnemia phyllitidis where gibberellin substitutes for antheridiogens with regard to induction of male sexual organs and dark germination. In this archegoniate TA caused a significant reduction in growth rate and morphogenesis of the gametophytes, inhibitions that were not abolished by simultaneous application of gibberellin.     

Ancient DNA from Bronze Age bones of European rabbit (Oryctolagus cuniculus)

The European rabbit (Oryctolagus cuniculus) is now widely distributed throughout the world as a result of transportation by man. The original populations, however, were confined to southern France and Spain. In order to investigate the role of human intervention in determining the genetic diversity of rabbit populations, we are studying the origin of rabbits introduced onto a small Mediterranean island (Zembra) near Tunis over 1400 years ago, by examining ancient DNA extracted from rabbit bones found both on Zembra and on the European mainland. Ancient DNA was successfully extracted from rabbit bones found at two archaeological sites dated to at least the Early Bronze Age (more than 3500 years ago) in south-central France, and compared to that found in modern mainland and island populations using a small variable region of the cytochromeb gene. The results confirm that the Zembra Island population is descended from that present over 1400 years ago. The technical aspects of DNA extraction from bones and the implications of this type of research for determining the origin of introduced rabbit populations are discussed.     

Chemical attraction of the eastern yellowjacket,Vespula maculifrons (Hymenoptera: Vespidae)

Summary Workers and queens of the eastern yellowjacket,Vespula maculifrons, are attracted to the artificial long-range attractant pheromone of the predaceous pentatomid,Podisus maculiventris. A 11 mixture of linalool or -terpineol and (E)-2-hexenal is as attractive toV. maculifrons workers as the pheromone.We thank A.S. Menke of the Systematic Entomology Laboratory, USDA, for identifying the yellowjackets. Mention of a company name does not imply endorsement by the US Department of Agriculture.