Degradation of bacterial lipopolysaccharide by gut juice os the snail Helix pomatia.

Lipopolysaccharides from several bacteria were selectively degarded by gut juice of the snail Helix pomatia with extensive loss of anticomplementary activity and changes in the electrophoretic pattern in polyacrylamide gels. The gut juice had little effect on ketodeoxyoctonate content or immunodominant sugars. The lipid A moiety of the lipopolysaccharide appeared to be the main site of attack.     

Epithelial homeostasis and the underlying molecular mechanisms in the gut of the insect model <Emphasis Type="Italic">Drosophila melanogaster</Emphasis>

Insects mostly develop on decaying and contaminated organic matter and often serve as vectors of biologically transmitted diseases by transporting microorganisms to the plant and animal hosts. As such, insects are constantly ingesting microorganisms, a small fraction of which reach their epithelial surfaces, mainly their digestive tract, where they can establish relationships ranging from symbiosis to mutualism or even parasitism. Understanding the tight physical, genetic, and biochemical interactions that takes place between intestinal epithelia and either resident or infectious microbes has been a long-lasting objective of the immunologist. Research in this field has recently been re-vitalized with the development of deep sequencing techniques, which allow qualitative and quantitative characterization of gut microbiota. Interestingly, the recent identification of regenerative stem cells in the Drosophila gut together with the initial characterization of Drosophila gut microbiota have opened up new avenues of study aimed at understanding the mechanisms that regulate the dialog between the Drosophila gut epithelium and its microbiota of this insect model. The fact that some of the responses are conserved across species combined with the power of Drosophila genetics could make this organism model a useful tool to further elucidate some aspects of the interaction occurring between the microbiota and the human gut.     

Anoxygene Reaktivierung der Zellvermehrung nach anoxybiotisch hervorgerufener Zytostase (Anabiose)

Summary In cell juice of aerobic fermenting and of only respiring yeast cells, a thermostable respiratory energy reserve is found which under rigorous anoxybiotic conditions effects a generative reactivation in contact with anabiotic fermenting yeast cells, butnot with only respiring ones. Also in cell juice of Jensen sarcoma and other carcinoma tissues, an adequate energy substance is recognized as being able to replace oxygen biologically.     

Digestive enzymes of some earthworms

Summary 4 species of tropical earthworms differed with regard to enzyme activity. The maximum activity of protease and of cellulase occurred in the posterior region of the gut of the earthworms. On the averageOctochaetona surensis shows maximum activity andDrawida calebi shows minimum activity for all the enzymes studied.     

Digestive physiology ofBradynopyga geminata (Odonata: Libellulidae)

Summary The pH of the gut ofB. geminata ranges from 5.5 to 6.8. The midgut is the main source of the digestive enzymes, secreting trypsin-like protease, chymotrypsin, aminopeptidase,a-amylase, maltase, sucrase, lactase and lipase.     

Über eine bakterielle Vorverdauung und eine proteolytische Hauptverdauung im Darm der Nashornkäferlarve (Oryctes nas. L.)

Summary The larva ofOryctes nas. L. shows a bacterial predigestion in the rectal-saccus. The main breakdown of proteins takes place in the middle gut, closely connected with the act of regurgitation.     

Aseptic rearing of the aster leafhopper,Macrosteles fascifrons (Stål), on a chemically defined diet

Summary The normal symbiotic aster leafhoppers,Macrosteles fascifrons, were reared under aseptic conditions on the holidic diet through 5 successive generations with normal rates of development, survival and reproduction. Thus the artificial diet is completely adequate for normal insects and dependence on gut organisms is not part of the physiology of this species.     

Labelling the adults of the tobacco caterpillarSpodoptera littoralis (Boisd.) (Prodenia littura F.; noctuidae: Lepidoptera) with P32

Zusammenfassung Radioaktive Markierung der Larven vonSpodoptera littoralis mittels³²P ist nicht nur in den daraus resultierenden Imagines, sondern auch in den Eiern und den daraus schlüpfenden F1-Räupchen gut nachweisbar.     

Sulla struttura dei cromosomi diAscaris megalocephala Cl. con particolare riguardo all'attacco al fuso

Zusammenfassung Die Untersuchung des Chromosomenzyklus während der Spermatogenese vonAscaris megalocephala bivalens Cl. ergab ein monozentrisches Verhalten der Chromosomen. Ein gut differenziertes Zentromer wird jedoch am Spindelansatz nicht gebildet.     

Nervenzellen im Bereich des ösophagus der Grillen und ihre mögliche Funktion

Summary Multiterminal nerve cells have been found in the foregut of crickets (Acheta domesticus (L.),Gryllus campestris L.) which are sensitive to stretching the wall of the gut. These cells are spontaneously active and they respond to stretch in a phasic-tonic way. Within the ventricular nerves there are also neurones being spontaneously active.     

Isolation of homogentisic acid from urine of alcaptonuric cases by means of an anion-exchanger

Zusammenfassung Die Homogentisinsäure liess sich aus alkaptonurischem Harn selektiv am schwach basischen Anionenaustauscher Anex adsorbieren. Nach der Elution mit Hilfe von 5M Essigsäure betrug die Ausbeute 60%. Die Methode ist auch im präparativen Ausmass gut durchführbar.     

A rapid colorimetric method for the determination of tobacco mosaic virus concentration in plant saps

Zusammenfassung Es wird eine neue kolorimetrische Schnellmethode zur Bestimmung des Nucleoproteidgehaltes von Tabakmosaikvirus im Saft von Tabakblättern beschrieben. Der Saft wird durch die Chloroform-Wasser-Emulsionstechnik geklärt, das Virus-Nucleoproteid durch 2,0M Trichloressigsäure gefällt und dann in 1,0N NaOH gelöst. Die durch Zusatz von Folin-Phenolreagens entstandene Farbe wird kolorimetrisch bestimmt. Die mit der neuen Methode erhaltenen Resultate stimmen gut mit denjenigen von Aktivvirusbestimmungen überein.     

On the decrement function of an action potential in a volume conductor

Zusammenfassung Eine Modifikation der Feldgleichung vonLorente de Nó wird einer Fourier-Transformation unterworfen. Dabei zeigt sich, dass das Dekrement einer jeden Frequenz eineK ₀-Funktion in ihrem eigenen Maßstab darstellt. Die theoretische Dekrementkurve stimmt gut mit der experimentell ausgearbeiteten überein.     

Radiation-induced castration in the female teleostean fish,Heteropneustes fossilis bloch

Zusammenfassung Indischen Katzenwels-Weibchen (Heteropneustes fossilis Bloch) wurden im Februar und April 5µc Co⁶⁰ injiziert, was zur vollständigen Unfruchtbarkeit führte. Alle Fische erholten sich aber innerhalb von 14 Tagen auffallend gut von den Injektionsschäden.     

Caractérisation de laβ-galactosidase d'Helix pomatia par immunoélectrophorèse

Summary Digestive juice ofHelix pomatia was studied by immunoelectrophoresis: after incubation with a chromogenic substrate, 5-bromo-4-chloroindol-3-yl--D-galactopyranoside, two-galactosidases were revealed.     

In vitro metabolism of the trichothecene 4-monoacetoxyscirpenol by fungus- and non-fungus-feeding insects

Summary The metabolism of the trichothecene 4-monoacetoxyscirpenol by intact gut tissue was determined in the fungus-feeding Nitidulid,Carpophilus hemipterus (L.) and the non-fungus-feeding caterpillars, the fall armyworm,Spodoptera frugiperda (J. E. Smith) and the corn earworm,Heliothis zea (Boddie). The primary metabolite was the hydrolysis product scirpentriol. The amount of metabolism by theC. hemipterus larvae was ca 10 times that of the caterpillars on a per mg protein basis, suggesting metabolic adaptation for feeding on fungi that may contain mycotoxins.Acknowledgment. The authors wish to thank S. Taylor for technical assistance.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned.     

On the percutaneous absorption of tribenoside applied topically to the mouse ear

Zusammenfassung Mit Hilfe von radioaktiv markierten Präparaten (6-Benzyl-C¹⁴ bzw. 6-Furanose-H³) wird gezeigt, dass auf die Haut appliziertes Äthyl-3,5,6-tri-O-benzylglucofuranosid (Glyvenol^®) bei der Maus gut resorbiert wird.     

Lucifensin, the long-sought antimicrobial factor of medicinal maggots of the blowfly Lucilia sericata

A novel homologue of insect defensin designated lucifensin (Lucilia defensin) was purified from the extracts of various tissues (gut, salivary glands, fat body, haemolymph) of green bottle fly (Lucilia sericata) larvae and from their excretions/secretions. The primary sequence of this peptide of 40 residues and three intramolecular disulfide bridges was determined by ESI-QTOF mass spectrometry and Edman degradation and is very similar to that of sapecin and other dipteran defensins. We assume that lucifensin is the key antimicrobial component that protects the maggots when they are exposed to the highly infectious environment of a wound during the medicinal process known as maggot therapy. We also believe that lucifensin is that long-sought larger molecular weight antimicrobial factor of the Lucilia sericata excretions/secretions believed to be effective against pathogenic elements of the wound microbial flora.     

Wall development and tetrazolium chloride reduction in heterocysts of blue-green algae,Anabaena ambigua

Zusammenfassung 2,3,5-Triphenyl-Tetrazolium-Chlorid (TTC) wird in den Heterocysten der BlaualgeAnabaena ambigua nur bei einer gut ausgebildeten Zellwand in grösseren Mengen reduziert. In allen übrigen Zellen, auch in den Proheterocysten, ist höchstens eine schwache TTC-Reduktion zu beobachten.

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Our thanks are due to the UGC, CSIR for the financial assistance and to the Head of the Department of Botany, for facilities.     

The infectivity of polyhedra of nuclear polyhedrosis virus (N.P.V.) after passage through gut of an insectpredator

Summary Polyhedral inclusion bodies (P.I.B.) of a nuclear polyhedrosis virus ofHeliothis punctigera (Lep.) were found in excreta ofNabis tasmanicus (Het.), a predator ofH. punctigera. An immunofluorescent counting method was used to estimate numbers of P.I.B. Bioassays demonstrated that no loss of infectivity occurred during passage through the gut.Acknowledgment. I am grateful for the comments and criticism offered by Dr D.E. Pinnock, I thank D.J. Cooper for preparation of materials for the immunofluorescent counting method and J. Hardy for supplying me with eggs ofH. punctigera; all of Department of Entomology, Waite Agricultural Research Institute, Glen Osmond, South Australia.