Ultrastructure of four types of striated muscle fibers in the atlantic hagfish (Myxine glutinosa,L.)

Summary Four types of striated muscle fibers with distinctive ultrastructure were defined in the Atlantic hagfish (Myxine glutinosa, L.): white, intermediate, and red fibers of m. parietalis, and red fibers of m. craniovelaris.White fibers are thick, contain very few mitochondria and fat vacuoles, and possess distinct and separate myofibrils with thin Z-disks and distinct M-lines. Intermediate fibers are thinner, possess largely similar myofibrils that often are even better separated due to a higher content of fat vacuoles and especially mitochondria and glycogen granules. Red fibers of m. parietalis contain large amounts of mitochondria, fat vacuoles, and glycogen granules. Their myofibrils possess M-lines, and although branching more, the myofibrils of red fibers conform with a Fibrillenstruktur pattern like those of white and intermediate fibers. Red fibers of m. craniovelaris are very thin, possess many smaller fat vacuoles, and large amounts of mitochondria and glycogen granules. The myofibrils are significantly thinner than in m. parietalis fibers, run as quite independent well separated units, possess thicker Z-disks, and lack M-lines. Large amounts of myosatellite cells are associated with these red fibers.Triads are located near A/I-junctions in all four fiber types and occur irregularly, the density of triads being different in the various fiber types.We are indebted to Dr. Finn Walvig, Biological Station, University of Oslo, Drøbak, for supply of hagfishes, and we also wish to thank Dr. Jan K. S. Jansen, Institute of Physiology, University of Oslo, for valuable suggestions during this study.     

Optical properties of the ocelli of Calliphora erythrocephala and their role in the dorsal light response

The 3 ocelli of the blowfly Calliphora erythrocephala, grouped close together on the top of the head (Fig. 1), have large, extensively overlapping visual fields. Together they view the entire upper hemisphere of the surroundings plus part of the lower hemisphere (Figs. 5, 7). It is shown for the lateral ocelli that despite the underfocussing of the ocellar lens large patterns are imaged on the receptor mosaic. Because of the astigmatism of the lens, patterns in longitudinal orientations are more accurately represented than in others (Fig. 3). Nevertheless, an artifical horizon rotated around the long axis of the animal does not elicit head roll. Likewise, changes of overall brightness in the visual field of the median and one lateral ocellus elicit only weak phasic-tonic dorsal light responses of the animal which supplement the tonic dorsal light responses mediated by the compound eyes (Figs. 9, 10). Our results show that, in Calliphora, the ocelli have little influence on head orientation during flight, and must be assumed to serve other functions.Abbreviations body pitch angle - head-tilt angle - DNOVS descending neuron of the ocellar and vertical cell systems - HR head roll - spatial wavelength - R roll angle - SD standard deviation     

Mitochondrial genetic damage induced in yeast by a photoactivated furocoumarin in combination with ethidium bromide or ultraviolet light

Summary Ethidium bromide (EB) and ultraviolet light (UV) in combination are known to produce a synergistic induction of petite mutants in yeast. Two other agents were combined with EB, 3-Carbethoxypsoralene (3 CPs) activated by 365 nm light or rays. EB in combination with 3 CPs also resulted in an enhanced production of petite mutants. After the photoaddition of 3 CPs in exponential phase cells, recovery of the petite mutation during dark liquid holding was inhibited by the presence of EB producing an enhanced number of petite mutants. The behavior of mitochondrial antibiotic resistance markers after individual and combined treatments with EB and 3 CPs indicates a random loss of markers after EB and a preferential loss of a certain region for the 3 CPs photoaddition. The combination of the two agents leads to an additivity of total drug marker losses rather than a synergistic loss. The combination of EB with rays produced no enhancement in petite induction. A combination of UV and 3 CPs showed a synergistic interaction for petite induction. These results indicate that the three agents, EB, UV and 3 CPs photoaddition may share a common repair step for mitochondrial lesions.     

Harzkonservierte fossile Vogelfedern aus der untersten Kreide

Zusammenfassung Harzkonservierte Fossilien ermöglichen bei Anwendung adäquater Methoden die morphologische Analyse der Feinmerkmale bis zur Auflösungsgrenze des Lichtmikroskops, Beobachtung in verschiedenen Ebenen und Richtungen, und somit konkrete Rückschlüsse auf die Wirkung und Bedeutung der Einzelelemente und des Gesamtgefüges.Eine so eingehende funktionsmorphologische Analyse mit Berücksichtigung der Positionsvariation (graduell verschiedene Gestaltung in gesetzmäßiger Abhängigkeit von der Lage innerhalb der Gesamtfeder) der Einzelelemente wie Abzweigungs-, Knick-, Neigungswinkel, Krümmung, Länge, Dicke, Querschnitt, Dichte, Differenzierungsgrad der verschiedenen Abschnitte von Rhachis, Rami, Radii inklusive Häkchen und Cirren wird erstmals für fossile Vogelfedern geliefert (hier als Abriß zu einer dokumentarisch und thematisch ausführlicheren Darstellung in Stuttgarter Beiträge zur Naturkunde).Diese Federn entstammen der untersten Unterkreide und sind damit nur relativ wenig jünger alsArchaeopteryx. Sie weisen extrem differenzierten Aufbau auf, der auf hohe flugtechnische und wärmeisolierende Leistungsfähigkeit schließen läßt.Die hier vorgelegten funktionsmorphologischen Ermittlungen an fossilen Körperkonturfedern mögen auch zu einer intensiveren Analyse der bis jetzt stark vernachlässigten Untersuchung ganz normaler Körperfedern rezenter Vögel anregen. Erst dann, nach umfassender Kenntnis ihrer Ausgestaltung innerhalb der verschiedensten rezenten Vogelgruppen, läßt sich überzeugend begründen, ob und wieweit die hier vorgelegten Federn dieses Unterkreide-Vogels noch ursprüngliche Elemente (Plesiomorphien) oder ihnen eigene Sonderbildungen (Autapomorphien) aufweisen; das gilt sowohl für morphologische wie für funktionelle Elemente der Gesamtstruktur.

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Resin-preserved fossil bird's feathers from the Lowermost Cretaceous

Summary Parts of some feathers, originating from a single bird, were discovered in our collections of Lower Cretaceous amber from the Lebanon mountains — which, in general, contains the oldest terrestrial microfossils preserved with all morphological details.These contour feathers of the trunk, which are nearly as old as Archaeopteryx (Lowermost Cretaceous: Neocomian/Uppermost Jurassic: Kimmeridigian) were studied with magnifications of 500–900 in several levels by a special technique. (In normal fossils, i.e., impressions, the granulation of the sediment and the fossil's bulky carbon remainders cause a blurred image even at a magnification of merely 100).Special emphasis was laid on the study of the individual elements' gradual variation, depending on the respective position within the total feather (position variation). Where appropriate, an analysis of lengths, quantity, degree of differentiation, angle of inclination, break, and branching, cross-sectional view, curvature, etc. of the rhachis, rami, distal and proximal radii, barbicles, hooklets, etc. were undertaken. [Through measurements of the depth of details the effects caused by a sloping position (apparent variation) may be precisely separated from the real variation.]On the basis of such a detailed knowledge of structure and relative position a thorough functional analysis of the single elements as well as the total system is given.Principal features: The production of plain stability in the feather's center, and of flexibility in its apical and lateral rims; dispersion of forces in case of pressure or a pulling load; function of the hooklets (which donot serve as an interlocking mechanism while the feather is in the normal resting position, but function with increasing braking action only when a neighboring ramus diverges to a precisely defined extent from its resting position) including the mechanism of their unhooking; devices for the avoidance of harmful hooking into contacted parts of other feathers; production of maximal stability by minimal air resistance, and of minute chambers (<0,00001 mm³) with still air for optimal heat isolation.Apart from this abstract, further information, accompanied by numerous figures, will be given in a later paper in Stuttgarter Beiträge zur Naturkunde.

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Veränderte Fassung eines am 11. 10. 1971 gehaltenen Vortrages auf der 83. Jahresversammlung der Deutschen Ornithologengesellschaft in Bonn.     

Über die Mikrovillibildung im fetalen Rattendünndarm

Zusammenfassung Die Frage, auf welche Weise die Enterocyten des fetalen Rattendünndarms das für die Mikrovillibildung benötigte Membranmaterial liefern, wurde elektronenmikroskopisch untersucht. Es wird angenommen, daß hufeisenförmige Strukturen, die aus mit elektronendichtem Material bedeckten Elementarmembranen bestehen und möglicherweise Längsschnitten durch kappenförmige Gebilde entsprechen, in das apicale Plasmalemm eingebaut werden und für die Bildung der Mikrovillispitzen verantwortlich sind. Diese Annahme gründet sich in erster Linie auf die Feststellung eines nahezu identischen Durchmessers von Hufeisen und Mikrovilli, auf die Lokalisation der Hufeisen im Terminalgespinst und ihr zahlenmäßiges Verhalten während der Mikrovillibildung. Die Hufeisen entstehen im Golgi-Apparat.

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The formation of microvilli in the fetal rat small intestine

Summary The origin of membranes required for the formation of microvilli has been investigated electronmicroscopically in enterocytes of fetal rat small intestine. It is assumed that horseshoe-like structures consisting of unit membranes covered with electron-dense material, which probably represent longitudinal sections through cap-like structures, are incorporated into the apical cell membrane and give rise to the tips of microvilli. This assumption is based chiefly on the almost identical diameters of horseshoes and microvilli, the localization of horseshoes in the terminal web, and the time of appearance and disappearance of horseshoes with regard to development of microvilli. There are indications that the horseshoes originate in the Golgi apparatus.

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.     

Effects of losartan on the collagen degradative enzymes in hypertrophic and congestive types of cardiomyopathic hamsters

The present study was undertaken to determine the effects of AT1 receptor blockade which occurred in response to losartan, on the extracellular matrix (ECM) degradation process in the Bio 14.6 (n = 12) and Bio 53.58 (n = 12) strains which are referred as models of hypertrophic and dilated cardiomyopathy, respectively. The administration of losartan (30 mg/kg/day) in hamsters from 10–20 weeks of age reduced the accumulation of the left ventricular collagen matrix in both of the Bio 14.6 and the Bio 53.58 strains. According to the RTPCR, the levels of mRNA for matrix metalloproteinase (MMP) and the tissue inhibitor of MMP (TIMP) were examined. MMP1, 2, 3, and 9 were more enhanced in both myopathic strains than in the control F1 strains. With losartan, the levels of MMP1, 2, 9, TIMP1 and 2 decreased in the both strains but those for MMP3 did not in Bio 14.6 strains. TIMP3 and 4 mRNA levels did not change in any of the experimental hamsters, whether treated or untreated with losartan. The Western blots also showed similar observations in the both strains as seen in mRNA expressions although MMP2 in the Bio 53.58 strains did not differ between treated and untreated with losartan. Although losartan has an inhibitory effect on collagen accumulation in the development of cardiomyopathy, MMPs (1, 2, 9) and TIMPs (1, 2) seem to be susceptible to responding to losartan in Bio cardiomyopathic hamsters.     

Activation of peritoneal macrophages in patients with gynecological malignancies by sizofiran and recombinant interferon-γ

We investigated the influence of the combined use of sizofiran, a-1,3-glucan and a recombinant interferon- (rIFN-) upon biological activities of peritoneal macrophages (M). The number of peritoneal M and the production of cytokines (interleukin-1, interferon- and tumor necrosis factor) was increased by the combined treatment. Fully activated peritoneal M based on the increased number of elongated pseudopods were observed by electromicroscope. Sizofiran seems to assure a sufficient supply of M to kill tumor cells in the peritoneal cavity and co-administered rIFN- seems to directly stimulate the accumulated M in addition to its direct cytotoxicity against tumor cells. This combination therapy may be a step to the prevention of the recurrence of gynecological malignancies including ovarian cancer, after a negative second-look laparotomy.Abbreviations rIFN- recombinant interferon- - IL-1 interleukin-1 - TNF tumor necrosis factor - SLL second look laparotomy     

Silver staining the chromosome scaffold

Cytological silver-staining procedures reveal the presence of a core running along the chromatid axes of isolated HeLa mitotic chromosomes. In this communication we examine the relationship between this core and the nonhistone chromosome scaffolding, isolated and characterized in previous publications from this laboratory. When chromosomes on coverslips were subjected to the steps used for scaffold isolation in vitro and subsequently stained with silver, the characteristic core staining was unaffected. Control experiments suggested that the core does not contain large amounts of DNA. When scaffolds were isolated in vitro, centrifuged onto electron microscope grids, and stained with silver, they were found to stain selectively under conditions where specific core staining was observed in intact chromosomes. These results suggest that the nonhistone scaffolding is the principal target of the silver stain in chromosomes.     

Characterization of a mouse monoclonal IgG3 antibody to the tumor-associated globo H structure produced by immunization with a synthetic glycoconjugate

Globo H (Fuc12Gal13GalNAc13Gal14Gal14Glc) is a carbohydrate structure that shows enhanced expression in many human carcinomas. From mice immunized with a globo H-KLH (keyhole limpet hemocyanin) synthetic conjugate an IgG3 monoclonal antibody (mAb VK-9) was derived that recognizes the globo H structure. Serological analysis showed that the minimal structure recognized by this mAb was the tetrasaccharide sequence Fuc12Gal13GalNAc13Gal. An isomeric structure with an internal GalNAc linkage was also recognized but less efficiently. mAb VK-9 did not react with many related structures, such as galactosylgloboside, globoside, H type 1, H type 2 blood group structures or fucosyl-gangliotetraosyl ceramide, but did react weakly with globo A ceramide. Not only did mAb VK-9 react with carbohydrate-protein conjugates but it could also recognize globo H-ceramide and human tumor cells expressing globo H. These results suggest that globo H-KLH could be explored as a vaccine in the treatment of carcinoma patients.     

Morphological colour change (2): The effects of total and partial blinding on epidermal ommochrome content in the stick insect,Carausius morosus Br.

Summary Fourth instar larvae of the stick insect,Carausius morosus, kept at 20°C in 16:8 LD, contained about 10 g/animal of epidermal ommochrome. Surgical removal of the ventral half of each eye caused an increase to 110 g/animal. A similar response (90 g/animal) is produced by masking the ventral eye-halves with black varnish. Masking or surgically removing the dorsal half of each eye only caused a slight increase (20 g/animal).The effect of total blinding, either by surgical removal of the eyes or optic lobes, or by electro-coagulation of the eyes, was similar to that of total darkness (40–60 g/animal). The effects of blinding were not enhanced by keeping the insects in total darkness. Eyes that had been destroyed or removed did not regenerate but were replaced by plain cuticle at subsequent moults. Consequently the blinding persisted through the following instars, and the fresh adults contained 300–600 g/animal as compared to 23 g in untreated animals.The results indicate that the effects of illumination on ommochrome pigmentation are mediated entirely through the compound eyes. Removal, destruction or disconnection of eyes or parts of them produced the same response as did lack of light stimulation in the same eyes or parts of eyes when left intact.First communication: J. Comp. Physiol.115, 185–193 (1977)Dedicated to Professor Peter Karlson on the occasion of his 50th birthday     

Electron microscopy of taste buds of the rat

Summary The taste buds of the circumvallate papillae have been examined by electron microscopy in OsO₄-fixed, PTA stained material or after KMnO₄ fixation. The microvilli of the receptor cells have terminal dilatations which presumably give an increased surface area for transduction. The extracellular spaces at the necks of the receptor cells near the bases of the microvilli are interrupted by closed contacts.The synapses have a well defined synaptic cleft suggesting a chemical rather than an electrical mode of transmission. Synaptic membrane specialisations differ from the membrane thickenings of other types of synapse. Presynaptic dense projections are present but there is no well define postsynaptic thickening. Vesicles occur in both pre- and postsynaptic components, but it is debatable whether or not they should be termed synaptic vesicles. Acknowledgements. We are indebted to Professor J. Z. Young, F. R. S., for his stimulating support, and to Mr. S. Waterman for skilled photography.     

On the role of the invariant glutamine at position 54 in the human choriogonadotropin β subunit

The twelve Cys and eight of the non-Cys residues are invariant in the glycoprotein hormone subunits from a variety of mammalian species. -Gin-54 of human lutropin (hLH) and choriogonadotropin (hCG) is one of these invariant amino acid residues. A single AG mutation in the LH gene of a patient presenting with hypogonadism resulted in the replacement of Gin-54 with Arg [1]. The authors also reported that an expressed mutant of hLH, with Arg replacing Gin-54, associated with the subunit, but there was no demonstrable binding of the mutant hormone to receptor. We have replaced Gin-54 in hCG with Glu and with Lys using site-directed mutagenesis. The expression plasmids pRSV-hCG (wild-type and mutants) were transiently transfected into CHO cells containing a stably integrated gene for bovine , and the media were analyzed for holoproteins, which were characterizedin vitro using competitive binding and steroidogenic assays with MA-10 cells. hCG(Glu-54) bound to almost as well as hCG wild-type, and the resulting heterodimer competed with [¹²⁵l]hCG binding to the LH/CG receptor and stimulated progesterone production to the same extent as the wild-type control. However, the apparent potencies, as judged by ED₅₀s, were less than those of the wild-type control, the effect being more pronounced in binding than in steroidogenesis. In contrast, hCG(Lys-54) associated very poorly with . Our results suggest that while Gin-54 in hCG participates in receptor binding, its major function appears to involve binding. Such dual functionality leads to interesting models for holoprotein formation and receptor binding.     

The contribution of size-fractionated plankton to biomass and primary production of phytoplankton in saline–alkaline ponds

Primary productivity, biomass and chlorophyll-a of size fractionated phytoplankton (<0.22 m, <3 m, <8 m, <10 m, <40 m, <64 m, <112 m and <200 m) were estimated in 6 ponds and 5 experimental enclosures. The results showed that the planktonic algae less than 10 m are important in the biomass and production of phytoplankton in saline–alkaline ponds. The production of size fractionated phytoplankton corresponding to <112 m, <10 m and <3 m in saline–alkaline ponds were 10.5 ± 6.6 , 8.6 ± 5.4 and 0.33 ± 0.1 mgC l^–1 d^–1, respectively. Mean community respiration rate was 1.80 ± 0.73, 1.69 ± 0.90 and 1.38 ± 1.12 mgC l^–1 d^–1, respectively. The average production of phytoplankton corresponding to micro- (10–112 m), nano- (3–10 m) and pico- (<3 m) were 1.61, 8.30 and 0.33 mgC l^–1 d^–1, respectively. The ratio of those to the total phytoplankton production was 15%, 79% and 3%, respectively. The mean respiration rate of the different size groups was 0.11, 0.31 and 1.38 mgC l^–1 d^–1; the ratio of those to total respiration of phytoplankton was 6%, 17% and 77%, respectively. The production of size-fractionated phytoplankton corresponding to <200 m, <10 m and <3 m in enclosures was 2.19 ± 1.63, 2.08 ± 1.75 and 0.22 ± 0.08 mgC l^–1 d^-1, respectively. Mean community respiration rates were 1.25 ± 1.55, 1.17 ± 1.42 and 0.47 ± 0.32 mgC l^–1 d^–1, respectively. The average production of phytoplankton corresponding to micro- (10–200 m), nano- (3–10 m) and pico- (<3 m) plankton was 0.11, 1.86 and 0.22 mgC l^–1 d^–1, respectively. The ratio of those to the total production of phytoplankton was 5%, 85% and 10%, respectively. The mean respiration rate of different size groups were 0.08, 0.72 and 0.46 mgC l^–1 d^–1, the ratio of those to total respiration of phytoplankton was 6%, 57% and 37%, respectively. The concentrations of chlorophyll-a of the phytoplankton in the corresponding size of micro- (10–112 m), nano- (3–10 m) and pico- (<3 m) plankton in the experimental ponds were 19.3, 98.2 and 11. 9 g l^–1, respectively. The ratio of those to the total chlorophyll-a was 15%, 76% and 9%, respectively. The concentrations of chlorophyll-a of phytoplankton micro- (10–200 m), nano- (3–10 m) and pico- (<3 m) plankton in enclosures were 1.7, 34.3 and 3.0 g l^–1, respectively. The ratio of those to the total chlorophyll-a was 4%, 88% and 8%, respectively.     

Transmembrane electron transport and the neutral theory of evolution

Based on the concept of pairs of basic functional states the evolution of the first chemiosmotic mechanism of energy conversion is discussed in terms of point mutations, gene duplications and of the neutral theory of evolution. A model for estimating the overall probability of the evolutionary step in question is presented, both for the selectionist and neutralist position. It is concluded that, concerning the present stage of knowledge, the evolution of transmembrane electron transport is an unsolved problem in evolutionary biology.     

Fine structure of the Malpighian tubes in the blood-sucking insect,Triatoma infestans Klug

Summary The ultrastructure of the distal cells in the Malpighian tubes ofTriatoma infestans Klug differs from that of the proximal cells in terms of types of striated border, and distribution of mitochondria and laminated concretions. This is in accordance with published data for another blood-sucking insect,Rhodnius prolixus Stahl. Other observations, however, elucidate cytoplasmic structures not yet reported inReduviidae insects. Layered membranous formations ending in spiral configurations are found in both cell types giving rise to layered membranous globules. Bundles of fibers made up of tubuli occur in the apical regions of the proximal cells in fasted animals. Glycogen deposits surround vacuole-like areas which are probably representing a stage in the formation of laminated concretions. Several globule types [lysosome-like structures, and layered membranous globules sometimes containing cell organelles (cytolysomes?)], are present in the distal and proximal cells, whereas laminated concretions are displayed only by the distal cells. The different globules are ascribed to various stages in the excretion of substances and the elimination of organelles. No special ultrastructural findings could be related to the diversified nuclear phenotypes previously described in the Malpighian tubes ofT. infestans.     

Ortstreue, Altersaufbau und Mortalit?t einer Population des Baumpiepers(Anthus t. trivialis)

Zusammenfassung 1. Von den in einer intensiv untersuchten Population des Baumpiepers in Nordbelgien beringten Nestlingen kehrten 24 junge und 3 junge zurück. 12 von 17 farbberingten Jungvögeln stammten dabei aus Erstbruten.2. 6 und die beiden waren Heimatansiedler, 1 Fremdansiedler, 6 geburtsortstreu und 2 Geburtsorts-Rücksiedler.3. Die mittlere Entfernung des Revieres vom Geburtsnest betrug bei den geburtsortstreuen 184±118 m, bei den anderen 818±368 m.4. Alte zeigen größere Umsiedlungsentfernungen als alte .5. Einjährige haben in der Population einen sehr hohen Anteil.6. 79 % der und 50 % der kehrten wieder in die Population zurück.7. Die Population umfaßte durchschnittlich 42 Brutpaare. Der Anteil an ledigen Altvögeln betrug 7 %. Die Siedlungsdichte erreichte einen Wert von 3,6 Brutpaaren pro 10 ha (ohne Gewässer).8. Angaben zu Paartreue, Paarauflösung, Bigynie und Paarbildung werden mitgeteilt.9. Aus den Rückkehrzahlen errechnet sich eine durchschnittliche Mortalität der jungen von etwa 65 %, eine Lebenserwartung von einem Jahr und ein Durchschnittsalter von 1,5 Jahren.10. 2,5 % der gelegten Eier bzw. 4,6 % der ausgeflogenen Jungvögel erbrachten brutreife Rückkehrer.11. Für alte errechnet sich eine Mortalität von 47,5 %, für alte von 66,7 % und eine Lebenserwartung von 1,6 bzw. 1,0 Jahren.12. Zum Erhalt der Population müssen jährlich etwa 46 % der ausgeflogenen Jungvögel bis zum nächsten Jahr überleben.13. Die untersuchte Population ist durchschnittlich aus 4,6 % geburtsortstreuen Jungvögeln, 41,3 % fremden Jungvögeln, 37,4 % ortstreuen Altvögeln und 16,7 % unbekannter Altvögel zusammengesetzt.

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Site-tenacity, age structure and mortality in a population of the tree pipit(Anthus t. trivialis) in northern Belgium

Summary 1. 24 first year and 3 first year , ringed as nestlings, returned in next years. 12 of 17 colour-ringed birds came from first broods.2. 6 and the 2 were Heimatansiedler, 1 Fremdansiedler, 6 geburtsortstreu and 2 Geburtsorts-Rücksiedler.3. The mean distances between the first territory and the birth nest of the geburtsortstreue and of the other were 818±368 m and 184±118 m respectively.4. Adult showed greater settling distances than adult .5. The percentage of first year was very high.6. 79 % and 50 % returned to their breeding population in next years.7. The mean density of the population was 42 pairs or 3,6 pro 10 ha. Unpaired adults amounted 7 %.8. Data on pair formation, mate-faithfulness and bigyny are treated.9. Calculation of mortality from the data of returned birds yielded a mortality of young of 65 %, a life expectancy of one year and a mean life time of 1,5 years.10. Sexual mature individuals derived from 2,5 % of all eggs laid and from 4,6 % of all youngs fledged.11. The computed mortality of adult is 47,5 % and of adult 66,7 %. The life expectancy is 1,6 and 1,0 years for adult and respectively.12. Allowing for the annual losses of adults a survival rate of first year birds of about 46 % is necessary.13. The mean annual composition of the population should be: 4,6 % geburtsortstreue juveniles, 41,3 % non-autochthonous juveniles, 37,4 % ortstreue adults and 16,7 % unknown adults.

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Mit Unterstützung des Nat. Fonds v. Wetenschappelijk Onderzcek, Brüssel.     

Trois nouveaux Nadejdolepis Spasskii & Sasskaya, 1954 (Cestoda: Hymenolepididae) parasites de Charadrii (Aves) de Tasmanie

Three species of Nadejdolepis from Tasmania, Australia, are described and illustrated. N. burgessi n. sp., a parasite of Charadrius ruficapillus, is 4-6 mm long, with rostellar nitiduloid hooks 63-66 m long, a short evaginated cirrus 13-16 m long with a short collar of thin spines 1 m long, a narrow and tubular sclerotinoid vagina 40-50 long and 3-4 m in diameter with a little ampulla 3-5 m in diameter at the proximal end, and a membranous atrial segment with smooth, short (1 m) and compact spines which are sometimes difficult to observe. N. smithi n. sp., a parasite of 40-50 long and 3-4 m in diameter with a little ampulla 3-5 m in diameter at the proximal end, and a membranous atrial segment with smooth, short (1 m) and compact spines which are     

Evolutionary origin of the class A and class C β-lactamases

Summary The protein sequences of 18 class A -lactamases and 2 class C -lactamases were analyzed to produce a rooted phylogenetic tree using the DD peptidase of Streptomyces R61 as an outgroup. This tree supports the penicillin-binding proteins as the most likely candidate for the ancestoral origin of the class A and class C -lactamases, these proteins diverging from a common evolutionary origin close to the DD peptidase. The actinomycetes are clearly shown as the origin of the class A -lactamases found in other non-actinomycete species. The tree also divides the -lactamases from the Streptomyces into two subgroups. One subgroup is closer to the DD peptidase root. The other Streptomyces subgroup shares a common branch point with the rest of the class A -lactamases, showing this subgroup as the origin of the non-actinomycete class A -lactamases. The non-actinomycete class A -lactamase phylogenetic tree suggests a spread of these -lactamases by horizontal transfer from the Streptomyces into the non-actinomycete gram-positive bacteria and thence into the gram-negative bacteria. The phylogenetic tree of the Streptomyces class A -lactamases supports the possibility that horizontal transfer of class A -lactamases occurred within the Streptomyces.     

Killing ofLegionella pneumophila by human serum and iron-binding agents

The inhibitory effect of serum on the growth and survival ofLegionella pneumophila Bloomington 2 was investigated. When incubated in the presence of 20%–50% normal human serum for 10 h, viability was decreased by >99%. Heat-inactivated or <40% normal serum supplemented with 50 M iron was not inhibitory. The addition of guinea pig complement to heat-inactivated serum resulted in killing of approximately 98% of the cells. Growth in buffered yeast extract broth was inhibited by the addition of ferric iron-binding compounds. Minimum bactericidal concentrations at 37°C were 10 M apotransferrin, 35 M 1,10-phenanthroline, and 50 M deferoxamine. Addition of iron chelators to normal serum did not accelerate killing. Egg yolk-passaged virulent strains and agar-grown avirulent strains exhibited similar serum sensitivity. Results of this study indicate that complement and serum transferrin are antagonistic to the growth ofLegionella in serum.