Effect of the polychlorinated biphenyl preparation, Aroclor 1242, on the quantity of neurosecretory material in the medulla terminalis X-organ of the fiddler crab, Uca pugilator.

Exposure of the fiddler crab, Uca pugilator, to the PCB preparation, Aroclor 1242, produces an increase in the quantity of neurosecretory material in the medulla terminalis X-organ. This Aroclor apparently inhibits release, but not synthesis, of one or more neurohormones.     

In vivo inhibition of citrate cleavage enzyme by polychlorinated biphenyls

Summary Polychlorinated biphenyls (Aroclor 1254, PCB) administered in the diet (0.01%, w/v) to rats inhibited citrate cleavage enzyme. The results suggest that the decreased activity might in part account for decreased fatty acid synthesis in the livers of PCB-treated rats.This research was supported by a grant from the National Institutes of Health (ES-00040). Aroclor 1254 was a gift of Monsanto Company, St. Louis, Missouri, USA.     

Polychlorinated biphenyl-induced modification of lymphocyte response to plant mitogens in rats

Summary In PCB-treated rats total white cell and differential counts and lymphocyte proliferative response to PWM were unaltered. The lymphocyte response to PHA was increased in treated animals.Acknowledgements. Supported by grants from the Medical Research Council of Canada. We thank the Monsanto Chemical Co., St. Louis, Mo., for donating Aroclor 1254 and Dr.P. Cano for the protein determinations and electrophoresis.     

The occurrence of 5-hydroxytryptamine in the holothurian,Pentacter crassa

Summary 5-Hydroxytryptamine (5-HT) and hypoxanthine were isolated chromatographically from the holothurianPentacter crassa. This study was initiated as a result of the observed hypotensive activity of aP. crassa extract. This activity was also encountered in extracts of the holothuriansThelenota ananus andStichopus chloronatus and can be attributed to 5-HT.     

Sterols of the brine shrimp,Artemia salina,from Mono Kake,California

Zusammenfassung Artemia salina vom Mono-See, Kalifornien, U.S.A., enhält Cholesterin und Cholestanol als ihr hauptsächlichstes Sterin. Diese Zusammensetzung ist ähnlich wie die jenige von im Laboratorium erzeugten Salz-Krabben und zwar trotzdem das Wasser des Mono-Sees ein pH von 9.6 und einen Salzgehalt von 2.23M hat¹⁶.

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Acknowledgment. This work was supported, in part, by a grant from the Long Beach (California) Heart Association.     

On the question of American eels,Anguilla rostrata versus European eels,Anguilla anguilla

Zusammenfassung Der amerikanische AalAnguilla rostrata (2n=38; 20M+18A) gehört einer anderen Spezies an als der europäischeAnguilla anguilla (2n=38; 32M+6A).

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This work was supported in part by a grant No. CA 05138 from the National Cancer Institute, U.S. Public Health Service.     

Helmholtz,the conservation of force and the conservation of vis viva

This paper investigates the relationship between Helmholtz's formulation of the principle of the conservation of force and the two principles well known in rational mechanics as the principle of vis viva and the principle of the conservation of vis viva. An examination of the relevant literature from Leibniz to Duhamel reveals both Helmholtz's indebtedness to that tradition and his creative refashioning of it as he endeavoured to craft an argument that would both prohibit the construction of a perpetuum mobile and the efficacy of a supposed vital force and demonstrate the necessity of an ontology of mass points subject to attractive and repulsive central forces depending solely on distance.     

Biosynthesis, immunity, regulation, mode of action and engineering of the model lantibiotic nisin

This review discusses the state-of-the-art in molecular research on the most prominent and widely applied lantibiotic, i.e., nisin. The developments in understanding its complex biosynthesis and mode of action are highlighted. Moreover, novel applications arising from engineering either nisin itself, or from the construction of totally novel dehydrated and/or lanthionine-containing peptides with desired bioactivities are described. Several challenges still exist in understanding the immunity system and the unique multiple reactions occurring on a single substrate molecule, carried out by the dehydratase NisB and the cyclization enzyme NisC. The recent elucidation of the 3-D structure of NisC forms the exciting beginning of further 3-D-structure determinations of the other biosynthetic enzymes, transporters and immunity proteins. Advances in achieving in vitro activities of lanthionine-forming enzymes will greatly enhance our understanding of the molecular characteristics of the biosynthesis process, opening up new avenues for developing unique and novel biocatalytic processes. Received 9 April 2007; received after revision 31 August 2007; accepted 28 September 2007     

Effect of bacterial antigens,propranolol, and insulin on the susceptibility of mice to hypothermic stress

Zusammenfassung Bordetella pertussis hat zwei Komponenten, eine mit derselben Wirkung wie Endotoxin vonSalmonella typhosa mit sofortiger kältesensibilisierender Wirkung, die andere mit einer um 5 Tage verspäteten Sensibilisierung. Beide Komponenten können hypoglykämisch wirken.

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This work was supported in part by Public Health Service Research Grant No. CC00223 from the Center for Disease Control, Atlanta, Georgia, through the Massachusetts Health Research Institute.     

G-banding patterns of the housefly,Musca domestica,autosomes and sex chromosomes

Summary G-banding patterns were found on the X-chromosomes of the housefly. This indicates the presence of major gene loci on these chromosomes, i.e. sex-linked genes. G-banding patterns were also found on the Y-chromosome of 2 preparations. The first polyploid cell (a tetraploid, 2n=24) forMusca domestica was observed in one of the banding preparations.     

Chitin in the epidermal cuticle of a vertebrate (Paralipophrys trigloides,Blenniidae, Teleostei)

Lectin binding, endo-chitinase binding and enzymatic degradation studies show that the epidermal cuticle of the bony fishParalipophrys trigloides (Blenniidae) is chitinous. This is the first evidence that a vertebrate species possesses a chitinous tissue. Recently aXenopus gene has been identified which has significant sequence similarity to the catalytic domain of yeast chitin synthase III, a chitin producing enzyme^1,2. Taken together these two findings imply that chitin synthesis capability may be a basic vertebrate feature.     

Phylogenetic relationship of the Brasilian leptodactylid frog generaCraspedoglossa,Cycloramphus andZachaenus

Summary Based on immunological comparisons of the serum albumins ofCraspedoglossa andZachaenus with antisera to albumin of several species ofCycloramphus, it is concluded that morphological and biochemical evolutionary rates have not been comparable within the study group. Taken together, the morphological and biochemical information demonstrate that whileZachaenus is a genetic member of theCycloramphus lineage, it has attained generic status.This study was supported by NSF grant No. DEB78-23396, the Amazon Ecosystem Research Program, Smithsonian Institution, the Fluid Research Fund, Smithsonian Institution, and the Museu de Zoologia da Universidade de São Paulo.The authors gratefully acknowledge the following colleagues for their help in procuring frog samples: R.I. Crombie, M.C. Duchêne, F.I. McCullough, F.C. do Val and P.E. Vanzolini.     

Peroxidase activity in the sponge,Iotrochota birotulata

Summary The spongeIotrochota birotulata contains a peroxidase which was partially characterized. This is the first report of a peroxidase in Porifera, originally thought to be devoid of such enzymatic activity.This study was supported by grant No. CA 21992 from the National Cancer Institute, DHEW.     

In situ hybridization of rDNA on chromosomes of the honeybee,Apis mellifera L.

DNA probes containing the repeated rDNA region ofDrosophila melanogaster (coding for e.g. 28S and 18S rRNA) hybridized in situ to distinct regions of two heterologous mitotic chromosomes of the honeybee, identifying the nucleolus organizing regions (NORs). The method allows a rapid establishment of a physical map ofApis mellifera using other DNA probes ofDrosophila. This is the first report on well-defined chromosomal markers in the honeybee.     

Desiccation in the black dragon,Hagenius brevistylus Selys

Summary Hagenius brevistylus lost mass by evaporation in a moderately desiccating environment at the rate of 20.4 mg h^–1, and died of desiccation in less than 1 day at a body mass of 79.8% of their normally hydrated mass. It was estimated thatHagenius minimally would have to consume the equivalent of 60% of its body mass each day to meet its daily water requirements. This amount of food is equivalent to that necessary to power flight of a dragonfly for 4.6h.This research was financed in part by a grant from the American Philosophical Society to C.R.T., and was conducted at the University of Michigan Biological Station, Douglas Lake (USA).     

Karyotype and chromosome banding in the reed frogHyperolius viridiflavus ommatostictus (Amphibia,Anura, Hyperoliidae)

Summary C-banding and mithramycin staining were used to characterize the karyotypes of 10 specimens of the African reed frogHyperolius viridiflavus ommatostictus from Tanzania. The diploid chromosome number is 2n=24. Although no heteromorphic sex chromosomes were present in the mitotic karyotypes, in many diakineses of male meiosis one or two bivalents exhibited an end-to-end arrangement. In the laboratory 7 out of 24 females changed sex spontaneously. This indicates that an XY/XX system of sex determination operates inH. viridiflavus ommatostictus.This study was supported by the Deutsche Forschungsgemeinschaft (Schm 484/2-4). We thank K. E. Linsenmair and C. M. Richards for helpful comments on an earlier draft.     

Identification of 2-deoxyecdysone from the mite,Tyrophagus putrescentiae

2-Deoxyecdysone was purified from the miteTyrophagus putrescentiae and monitored by a radioimmunoassay. The compound was identified by GC-MS and LC-MS. This is the first report of an endogenous ecdysteroid from a mite.     

Emerging roles of the oxysterol-binding protein family in metabolism, transport, and signaling

OSBP (oxysterol-binding protein) and ORPs (OSBP-related proteins) constitute an enigmatic eukaryotic protein family that is united by a signature domain that binds oxysterols, sterols, and possibly other hydrophobic ligands. The human genome contains 12 OSBP/ORP family members genes, while that of the budding yeast Saccharomyces cerevisiae encodes seven OSBP homologues (Osh). Of these, Osh4 (also referred to as Kes1) has been the most widely studied to date. Recently, three-dimensional crystal structures of Osh4 with and without sterols bound within the core of the protein were determined. The core consists of 19 anti-parallel β-sheets that form a near-complete β-barrel. Recent work has suggested that Osh proteins facilitate the non-vesicular transport of sterols in vivo and in vitro, while other evidence supports a role for Osh proteins in the regulation of vesicular transport and lipid metabolism.This article will review recent advances in the study of ORP/Osh proteins and will discuss future research issues regarding the ORP/Osh family. Received 17 July 2007; received after revision 14 August 2007; accepted 12 September 2007     

Structure revision and cytotoxicity of the germacranolide,stizolicin, fromStizolophus balsamitus (Asteraceae)

Summary The structure of the cytotoxic sesquiterpene lactone, stizolicin, reisolated fromStizolophus balsamitus (Centaurea b.) was revised to atrans, trans germacranolide (1) on the basis of simultaneous application of lanthanide shift reagent and NOE in the NMR.The authors acknowledge the use of the Purdue University Biomedical Magnetic Resonance Laboratory (NIH grant No. RR01077). Support of contract No. N01-CM-97296 and Grant No. CA-33326 from the National Cancer Institute, HHS is gratefully acknowledged. This is paper 18 in the series Potential Antitumor Agents.