bluuebunny/crossref_metadata_2025 huggingface dataset:
Inhibitory effect of Anabaena sp. on in situ filtering rate of Daphnia
Authors: Chow-Fraser Patricia , Sprules W. Gary
Published: August 2008

We found that in situ filtering rates of Daphnia spp. measured in a lake containing Anabaena were significantly lower than those measured in a filament-free lake. Even after accounting for the depressing effects of high nannoplankton biomass concentration, filtering rates in the lake with Anabaena were 64% lower than those from the filament-free lake. We also found that filtering rates for Daphnia pulex in laboratory experiments were lower when Anabaena was present in experimental beakers than when Chlorella was present. When Anabaena was removed from Three Mile Lake water, filtering rates compared closely with predicted rates based on nannoplankton concentration and carapace length alone. Our analysis indicates that the presence of Anabaena filaments depresses Daphnia grazing rates in general, and that the filaments themselves are ingested at a lower rate than algae such as Chlorella.
Duckling production of the Oldsquaw in relation to spring weather and small-rodent fluctuations
Authors: Pehrsson Olof
Published: August 2008

The duckling production of the Oldsquaw (Clangula hyemalis) was studied between 1969 and 1974 in Torne Lapmark in northern Sweden. The degrees of relationship among various indices of reproductive output, climatic factors, and fluctuations in small rodents were estimated. Total brood and duckling production were calculated. A correlation between first observations of broods and time of arrival of spring indicated that the Oldsquaw breeds as early as possible, an adaptation to the utilization of ephemeral lakes. Peaks in duckling production correlated well with peaks in the abundance of small rodents but not as well with climatic variables. Twice as many ducklings were produced during the rodent peak years as during the intervening years, and the densities of the Oldsquaw population were highest the year after these peaks in brood production. The positive correlation between duckling production and population size in small rodents seems to be analogous to grouse–rodent cycles, and both are best explained by the predator-shift or the alternative prey hypothesis.
Avian Haemoproteidae. 23. The haemoproteids of the avian family Coraciidae (rollers)
Authors: Bishop Madonna A. , Bennett Gordon F.
Published: August 2008

The haemoproteids of the avian family Coraciidae are reviewed. Haemoproteus coraciae de Mello and Afonso, 1935 is redescribed; H. coraciae var. benghalensis de Mello and Afonso, 1935, H. coraciae Vallés, 1938 nec de Mello and Afonso, H. velascoi Tendeiro, 1947, H. cruzferreirae Tendeiro, 1947, H. fontesi Tendeiro, 1947, and H. fontesi var. cyanogasteri Tendeiro, 1947 are declared synonyms of H. coraciae and Haemoproteus eurystomae n. sp. is described from Eurystomus orientalis. Haemoproteid records from the Coraciidae are summarized.
Cytogenetic studies in North American minnows (Cyprinidae). XII. Patterns of chromosomal nucleolus organizer region variation among 14 species
Authors: Gold John R. , Amemiya Chris T.
Published: August 2008

The chromosomal nucleolus organizer region (NOR) phenotypes of eight species of North American cyprinid fish are documented. This brings the total number of cyprinid species examined for chromosomal NORs to 14. At least 10 different NOR chromosome phenotypes are identifiable among the 14 species. These interspecific variations include differences in the (haploid) number of chromosomal NORs, the chromosomal location(s) of the NORs, and the type(s) of chromosomes upon which the NOR is located. Intraspecific variations or heteromorphisms of NOR chromosomes also occur, but are of a qualitatively different nature than the NOR variants observed between species. Arrangement of the interspecies NOR differences into phylogenetic hypotheses yields results which are not discordant with present concepts of North American cyprinid taxonomy, and in fact support the hypothesis of a close relationship between the cyprinid genera Notropis and Pimephales. These data suggest that NOR chromosome phenotypes will be useful in resolving problems in cyprinid systematics. The data also show that at least one or more chromosomal changes involving the NOR separate most of the species examined, and that at least nine different chromosomal rearrangements have occurred since the 14 species last shared a common ancestor. This suggests that chromosomal changes in cyprinids have been much more frequent than previously thought.
Resource defense and priority of access to food by the mate in pigeons
Authors: Lefebvre Louis , Henderson Derin
Published: August 2008

When pigeons in a group compete for access to a spatially restricted food source, feeding by one bird may coincide with defense of the area around the source by that bird's mate. Defense while the mate is feeding varies between individuals, between trials, and between sexes, males defending more than females. Priority of access to food, as measured by the time required for 5 min of feeding, is highly correlated with the amount of defense performed by the mate. Satiation reduces but does not abolish defense. Birds within a mated pair have similar positions in the priority of access hierarchy. Pair bonds in pigeons may partially function as reciprocal coalition systems used in competition for resources.
Chromatin distribution pattern and cell functioning
Authors: Sahota T. S. , Peet F. G. , Ibaraki A. , Farris S. H.
Published: August 2008

Chromatin distribution patterns of the nuclei of the follicular epithelial cell of Dendroctonus pseudotsugae Hopk. (Scolytidae: Coleoptera) were analyzed after creating their digital images. The five cell populations examined consisted of follicular epithelial cells at three different stages of structural and functional differentiation and two populations in which this differentiation was blocked. The results show that chromatin distribution patterns differ when cells are structurally and functionally different but are not different in cells that are structurally, developmentally, and functionally similar. The procedures are capable of detecting minute differences and appear useful for early detection of developmental and functional changes in relation to normal and pathological conditions.
Age-related variation in song repertoire size and repertoire sharing of yellow warblers (Dendroica petechia)
Authors: Cosens Susan E. , Sealy Spencer G.
Published: August 2008

Songs of male yellow warblers (Dendroica petechia), ranging from 1 to 6 years of age, were recorded in the spring and summer of 1984. Recorded repertoire size and number of songs shared with neighbours varied positively with age in the spring but not in summer. Neither clutch initiation date nor fledging success varied with age or number of songs shared but both measures of reproductive success varied with size of recorded song repertoire.
Growth of grey seal (Halichoerus grypus) neonates: differential maternal investment in the sexes
Authors: Kovacs Kit M. , Lavigne D. M.
Published: August 2008

Male grey seals are larger at birth, grow faster during the nursing period, and are weaned at a heavier mass than females. Estimated mean energy expenditure by females from conception to the time of weaning (maternal investment), including the heat increment of gestation, cost of foetal tissue, and energy contained in milk acquired during the nursing period, was greater for male than for female offspring. This pattern of energy investment by female grey seals in their young is consistent with Maynard Smith's model of sexual investment (J. Maynard Smith. Behav. Ecol. Sociobiol. 7: 247–251. 1980).
Thermal acclimation of locomotor performance in anuran amphibians
Authors: Miller Kirk , Zoghby Gregory M.
Published: August 2008

Acclimation is the principal strategy employed by amphibians in coping with environmental temperature changes, yet acclimation has only rarely been shown to affect aspects of whole-organism function in amphibians. We examined the influence of a period of acclimation on the effect of temperature on locomotion in three anuran species. Giant toads, Bufo marinus, moved most quickly at 22 °C, and acclimation to that temperature further improved performance (inverse compensation). Leopard frogs, Ranapipiens, also moved most quickly at 22 °C, but acclimation to 12 °C improved locomotor performance at that temperature (positive compensation). Clawed frogs, Xenopus laevis, in contrast, moved most quickly at 12 °C and acclimation did not affect locomotor performance in this species (no compensation). Thus, while acclimation clearly affects locomotor performance in some anuran species, the direction of change differs among them.
Dimorphisme sexuel et variations morphométriques chez l'hermine, Mustela erminea cicognanii
Authors: Raymond Michel , Bergeron Jean-Marie
Published: August 2008

Lengths and weights were measured in a group of live ermines captured between 1978 and 1981 on agricultural lands in southern Quebec to determine the importance of size dimorphism, as well as evaluating intrasexual variations within a particular group on the one hand, and variations between the populations on the other. Mean weight of males (112,1 g) was nearly twice that of females (59,8 g) and the dimorphism index was 1,9. Mean weights varied significantly between years as a result of the relative abundance of young, especially males. It thus seems that variations either in length or weight are significantly lower in females, even after the effect of the number of young males has been corrected. A comparison of length and weight measurements of individuals in different groups of northeastern North American ermines showed that variability is considerably lower in females. These results agree with the hypothesis that female size is adjusted to that of a dominant prey species.[Journal translation]
Sélection des proies par l'hermine en captivité
Authors: Raymond Michel , Bergeron Jean-Marie
Published: August 2008

Certain aspects of prey selection were studied in ermines (Mustela erminea) kept in an enclosed arena that simulated a temporary meadow. Four males and eight females were involved in the 12-h experiments. Four types of prey were used: (i) meadow voles (Microtus pennsylvanicus), (ii) deer mice (Peromyscus maniculatus), (iii) short-tailed shrews (Blarina brevicauda), and (iv) young albino rats (Rattus norvegicus). Males were more efficient at catching prey than females, both in number of individuals and number of species captured. Meadow voles and rats were the prey captured most regularly and rapidly by both males and females. Males were more efficient at catching deer mice, but shrews were rarely captured. There was a great similarity in the performance of the four males, but considerable variation was observed among the females. No food preference could be detected in these experiments. The results are discussed in relation to food preferences observed during studies of ermines in a natural environment.[Journal translation]
On the morphology of developing eggs of the camel tick Hyalomma dromedarii Koch, 1844
Authors: Gohary M. El , Kamel M. Y. , Madbouly M. H.
Published: August 2008

External egg morphology of the camel tick Hyalomma dromedarii was studied. Injection of egg-laying females with 1% trypan blue resulted in incorporation of vital stain in the oviposited eggs. Daily measurements of fresh eggs revealed changes in egg length and width during embryonic development. Scanning electron microscopy showed the outermost layer of the egg to be spongy and porous containing clear pits of different sizes. An elevated longitudinal hatching ridge encircled the egg chorion. The development of cephalothorax, appendages, Malpighian tubules, and rectal sacs were monitered.
Nemhelix bakeri n.gen., n.sp. (Nematoda: Cosmocercinae) parasite de l'appareil génital de Helix aspersa (Gastropoda: Helicidae) en France
Authors: Morand S. , Petter A. J.
Published: August 2008

Nemhelix bakeri n.gen., n.sp. (Cosmocercinae), from the genital tract of Helix aspersa Miiller (Helicidae) in France, is described. The new genus is characterized by a rounded oral opening without lips. The authors presume that the Cosmocercinae arose in amphibians and became parasites of molluscs secondarily and that the two species became molluscan parasites independently.
The subfamily Chantiinae in the family Phytoseiidae (Acari: Gamasina)
Authors: Chant D. A. , Yoshida-Shaul E.
Published: August 2008

The tribe Chantiini Pritchard and Baker is proposed for elevation to subfamily status in the family Phytoseiidae. Members of the subfamily Chantiinae are characterized by their unique dorsal chaetotaxy: a combination of five pairs of setae (j3, z2, z3, z4, s4) on the lateral area of the podoscutum, which differs from other phytoseiid species that also have five pairs (j3, z2, z4, s4, s6), and from the more common four (j3, z2, z4, s4) or six (j3, z2, z3, z4, s4, s6) pairs in the family. Two genera, Chantia Pritchard and Baker and Diadromus Athias-Henriot new status, are included in the new sub family. The genus Chantia is monotypic, represented by the type-species C. paradoxa Pritchard and Baker. The genus Diadromus includes four species: D. contiguus (Chant) comb, nov., the type species; D. dominiquae (Schicha and Guttierrez) comb, nov.; D. separatus (Wu and Li) comb. nov.; and D. tengi (Wu and Li) comb. nov. The systematic concept of the new subfamily Chantiinae in relation to other subfamilies in the family Phytoseiidae is outlined. Previous systematic concepts concerning the species in the two genera are reviewed. Keys to the female adults of the genera, the species groups, and the species are provided. Descriptions of each genus and species are given.
Somatostatin reduces plasma growth hormone levels during seawater adaptation in coho salmon, Oncorhynchus kisutch
Authors: Sweeting R. M. , McKeown B. A.
Published: August 2008

Plasma growth hormone levels were measured in coho salmon exposed to seawater to examine whether somatostatin has growth hormone release inhibitory action in salmon. Somatostatin (2 μg/10 g body weight) was injected prior to exposure to seawater and samples were taken 6 and 12 h postexposure. The results indicate that somatostatin does have potent growth hormone release inhibitory action in salmon, as it does in other teleosts.
Spontaneous hatching of Fallacohospes inchoatus, an umagillid flatworm from the northeastern Pacific crinoid Florometra serratissima
Authors: Shinn George L.
Published: August 2008

Egg capsules of Fallacophospes inchoatus are roughly tetrahedral in shape, have a hydratable adhesive covering, and typically contain two zygotes and 40–50 yolk cells. Embryos complete development in 40–42 days and hatch spontaneously when kept in seawater at 8–10 ° C. This observation suggests that the suspension-feeding crinoid hosts are infected by eating free-swimming larvae rather than by eating egg capsules that contain embryos, which is the case for deposit-feeding echinoderms that harbour umagillids. The possibility is raised that umagillids originally evolved as parasites of suspension-feeding echinoderms and that the mode of reproduction of crinoid-inhabiting umagillids is primitive for the family.
La majuscule dans la nomenclature biologique
Authors: Chabot Jacques , David Normand
Published: August 2008

On the basis of usage, grammatical rules, and simple logic, the authors propose that the following convention be used in French for the common names of animal and plant species: the noun and the adjective, when it precedes the noun, are written with initial capital letters.
Developmental deformities in the parthenogenetic lizard Cnemidophorus uniparens (Teiidae) and the "anomalous male" phenomenon
Authors: Billy Allen J.
Published: August 2008

Parthenogenetic species of lizard occasionally produce male progeny characterized by developmental defects and low viability. Production of anomalous males is an unresolved problem in sexual differentiation as parthenogenetic female lizards are expected to produce female offspring. The "anomalous male" phenomenon was examined by sexing nonviable embryos produced by the parthenogenetic whiptail lizard Cnemidophorus uniparens. Twenty-six deformed embryos were obtained; all were female except for three which did not possess gonads. Male embryos were not detected. Developmental deformities found in Cnemidophorus embryos included anophthalmia, micropthalmia, encephalocoele, hypoplasia of the lower jaw, head foreshortening, gastroschisis, and malformations of the vertebral column. Several embryos possessed a combination of defects. Four hypotheses are presented to account for production of anomalous males by reptilian parthenoforms. Three hypotheses involve production of sex-reversed males (genetic females). A fourth hypothesis asserts that anomalous males are derived from hybridization events between a female from a unisexual species and a male from a bisexual species. Of the four hypotheses, the hybridization hypothesis has the greatest utility in explaining production of anomalous males by parthenogenetic lizards.
Seasonal changes in feeding motivation of juvenile Atlantic salmon (Salmo salar)
Authors: Metcalfe Neil B. , Huntingford Felicity A. , Thorpe John E.
Published: August 2008

It is known that juvenile Atlantic salmon populations divide into two size categories in their first autumn. The larger fish migrate to sea the next summer, whereas the lower modal group fish remain in freshwaters for at least another year. The size difference arises from a reduced food intake by lower modal group fish in autumn. We experimentally investigated the feeding motivation of lower modal group salmon from July to September of their 1st year. Feeding motivation declined through the season, regardless of competition, food supply, or water temperature. This was evident at each stage in the sequence of capturing prey: orientation was less likely to lead to attack, and an attack was less likely to result in the food being consumed. Fish also reduced the distances over which they would travel to intercept food, and delayed their attacks until passing particles had reached their closest approach. There was thus a general shift in foraging strategy in most fish towards minimizing the costs of obtaining a maintenance ration. It would therefore appear that lower modal group juvenile salmon do not grow during the winter as a result of internal suppression of appetite, which commences in midsummer.
Kroyeria caseyi sp.nov. (Kroyeriidae: Siphonostomatoida), a parasitic copepod infesting gills of night sharks (Carcharhinus signatus (Poey, 1868)) in the western North Atlantic
Authors: Benz George W. , Deets Gregory B.
Published: August 2008

Kroyeria caseyi sp.nov. (Kroyeriidae: Siphonostomatoida) is described from male and female specimens collected from gills of night sharks (Carcharhinus signatus (Poey, 1868)) captured in the western North Atlantic. Kroyeria caseyi is the only known member of the Kroyeriidae that is a mesoparasite, females being found partially embedded in the interbranchial septa of their hosts. Kroyeria caseyi is easily distinguished from other Kroyeria species by the armature of its swimming legs. Additionally, the genital complex of female K. caseyi is extremely long, composing up to 96% of the total body length. With some females reaching over 6 cm long, K. caseyi dwarfs all known congeners. First-stage nauplii collected from ruptured egg sacs are also described.
Eudactylinodes keratophagus sp.nov., the first record of Eudactylinidae Kabata, 1979 (Copepoda: Siphonostomatoida) from horn sharks (Heterodontus francisci (Girard, 1854), and H. mexicanus Taylor and Castro-Aguirre, 1972)
Authors: Deets Gregory B. , Benz George W.
Published: August 2008

Eudactylinodes keratophagus sp.nov. is described from specimens found amongst gill lamellae of the horn sharks Heterodontus francisci and H. mexicanus collected from Pacific waters off southern California and the Sea of Cortez, respectively. This is the first record of a eudactylinid copepod from heterodontid elasmobrachs.
The haemocytes and their classification in the larvae and pupae of Mamestra brassicae (L.) 1758 (Lepidoptera; Noctuidae)
Authors: Pelc Radek
Published: August 2008

Six types of free haemocytes, viz., prohaemocytes, plasmatocytes, granulocytes, spherulocytes, oenocytoids, and cystocytes were distinguished in the haemolymph of larvae of the third to sixth instars, prepupae, and pupae of Mamestra brassicae. The haemolymph also contained sporadic adipohaemocytes (a type of granulocyte). Different observation techniques showed only small differences in proportion between (i) living and (ii) fixed and stained cells, and none of the staining techniques showed any differences in staining capacity among haemocytes taken from different instars and from prepuae and pupae of different ages. Both Giemsa and Pappenheim staining gave similar results except for the spherulocytes and granulocytes. The total cell counts per μL of haemolymph were 15 000 to 22 000. In the larvae and the prepupa, plasmatocytes (25–58%) and granulocytes (28–48%) occurred in the highest proportions. The first five cell types mentioned above were found to divide in larvae; the first three and the oenocytoids also divided in the prepupa.
New taxa of Rhagidiidae (Acari: Prostigmata) from North America. Part I
Authors: Zacharda Miloslav
Published: August 2008

The following taxa of Rhagidiidae from North America are described as new: Lindquistula multisolenidiata sp.n., gen.n., Kouchibouguacia cryptosolendiata sp. n., gen.n., Robustocheles californiensis sp.n., Rhagidia pasadenensis sp.n., Rhagidia compressa sp.n., Parallelorhagidia parva sp.n., and Foveacheles vancouverensis sp.n.
Long-term effects of an insecticide on a stored-wheat ecosystem
Authors: White N. D. G. , Sinha R. N. , Mills J. T.
Published: August 2008

Two granaries near Winnipeg, each containing 141 of dry wheat, were filled in September 1982 and the impact of a contact insecticide on the ecosystem was determined monthly for 27 months. The wheat in one granary was treated with malathion prior to storage and the wheat in the other was left untreated. Variables monitored throughout each bulk included: introduced insect and naturally occurring mite numbers, seed germination, seed-borne mycoflora, insecticide residue levels, and seed temperature and moisture. There were significant differences (P < 0.01) in most variables within granaries between samples from the top of the grain bulk and 1-m depth. Multivariate analysis of variance indicated significantly more (P < 0.01) arthropods and more seed infection by the fungus Penicillium in the control granary. Principal component analysis of data from each granary on each sampling date indicated the first components, which accounted for most of the variation in the systems, mainly involved temperature, moisture, fungi, and insecticide (when present); the second components involved fungi; and the third components involved fungi and arthropods, even in the treated ecosystem. The presence of a contact insecticide in a stored-wheat ecosystem had significant effects on the faunal community and definite but less conspicuous effects on the mycofloral community.
Trophic preferences and feeding morphology of two pulmonate snail species from a small New England pond, U.S.A.
Authors: Kesler David H. , Jokinen Eileen H. , Munns Jr. Wayne R.
Published: August 2008

Pseudosuccinea columella and Physa vernalis, the two dominant snail species inhabiting a small New England pond, are compared on the basis of trophic preferences and food gathering anatomy. While the composition of stomach contents of both pulmonates varied similarly over a year's time, significant differences were found between species. Pseudosuccinea individuals consumed relatively more filamentous algae and sand than did Physa, while Physa ingested a greater proportion of detritus. Pseudosuccinea appears to be omnivorous while Physa appears to be a detritivore. The jaws, radulae, and stomachs (crop-gizzards) of the two species differ markedly and are consistent with dietary differences.
Three-dimensional predator–prey interactions: a computer simulation of bird flocks and aircraft
Authors: Major Peter F. , Dill Lawrence M. , Eaves David M.
Published: August 2008

Three-dimensional interactions between grouped aerial predators (frontal discs of aircraft engines), either linearly arrayed or clustered, and flocks of small birds were studied using interactive computer simulation techniques. Each predator modelled was orders of magnitude larger than an individual prey, but the prey flock was larger than each predator. Expected numbers of individual prey captured from flocks were determined for various predator speeds and trajectories, flock–predator initial distances and angles, and flock sizes, shapes, densities, trajectories, and speeds. Generally, larger predators and clustered predators caught more prey. The simulation techniques employed in this study may also prove useful in studies of predator–prey interactions between schools or swarms of small aquatic prey species and their much larger vertebrate predators, such as mysticete cetaceans.The study also provides a method to study problems associated with turbine aircraft engine damage caused by the ingestion of small flocking birds, as well as net sampling of organisms in open aquatic environments.
Distributional patterns of the ctenophores Pleurobrachia pileus and Beroe cucumis in the Bay of Fundy region, Canada
Authors: Milne W. R. , Corey S.
Published: August 2008

The distribution and relative abundance of Pleurobrachia pileus (O. F. Müller, 1776) and Beroe cucumis (Fabricius, 1780) within the Bay of Fundy and adjacent waters were examined over an 8-year period, either twice (spring and fall, 1975 and 1976) or three times (spring, summer, and fall, 1977 through 1982). Pleurobrachia pileus occurred in all surveys, maintaining a persistent centre of abundance over the southwest Nova Scotia shelf. Secondary centres of occurrence were located within the upper bay and Grand Manan–Maine regions, and were maintained by immigration from the southwest Nova Scotia region. Small P. pileus were abundant during the summer and fall, while larger animals were found in the spring. The larger numbers of smaller ctenophores within the upper bay and Grand Manan–Maine regions may reflect shrinkage of larger animals because of lack of food. Pleurobrachia pileus displayed a lack of significant affinity with the major recurrent group of zooplankton species found within the Bay of Fundy. Beroe cucumis was observed to be an immigrant into the Bay of Fundy in the spring and fall and generally occurred in areas of deeper waters, with recorded abundances usually low.
The relationship between crop size and egg production in Rhodnius prolixus
Authors: Davey K. G. , Maimets I.-K. , Ruegg R. P.
Published: August 2008

Earlier work showed that the number of eggs produced by a virgin female is smaller than that produced by a mated female. The current paper shows that this results not from a difference in rates of egg production, but from the operation of the same linear rate for different times. Denervating the corpus allatum in virgin females extends the time over which the same rate of egg production operates, thus indicating that the inhibition of egg production in virgin females results from a nervous inhibition of the corpus allatum. The initial rate of emptying of the crop is also approximately linear in both virgin and mated females. Later, crop emptying slows in virgins and remains linear in mated females. When these relationships are disturbed by plugging the anus of females before feeding, the rate of crop emptying in virgins more closely resembles that in mated females, and the difference in egg production between mated and virgin females disappears. These results are put into the context of a hypothesis which predicts that the degree of distension of the crop is an important determinant of the length of time that the corpus allatum remains active.
The effect of isoproterenol on isolated muskrat and guinea pig hearts
Authors: McKean Thomas A.
Published: August 2008

Isoproterenol, a β-adrenergic agonist, was given by bolus injection to Langendorff-perfused muskrat and guinea pig hearts. Bolus content ranged from 18 to 29 200 pmol. The hearts responded by increasing left ventricular pressure, heart rate, and release of lactate. The drug threshold was similar for the hearts of the two species but the magnitude of the response differed both at threshold and at saturation doses. The increase in left ventricular pressure and heart rate was greater in guinea pig hearts compared with muskrat hearts. Lactate release was stimulated earlier and increased more in muskrat hearts compared with guinea pig hearts. The weak β-adrenergic stimulation of heart rate and left ventricular pressure in the muskrat may be of benefit when the animal dives to escape a potential predator. Under these conditions of fear, exercise, hypoxia, and diving there would be opposing effects of sympathetic versus vagal stimulation of the myocardium. The sympathetic effect would be to increase myocardial oxygen consumption while the vagal effect would be to reduce it. In the diving mammal the vagal effect predominates and this may be augmented by a blunted rate and pressure response to β-stimulation.
Ferritin as an exogenously derived yolk protein in Helisoma duryi (Mollusca: Pulmonata)
Authors: Miksys S. , Saleuddin A. S. M.
Published: August 2008

The iron storage protein ferritin is identified as a yolk component in Helisoma duryi by histochemistry, electron microscopy, energy dispersive analytical x-ray analysis, and radioimmunoassay. It was found to accumulate in the yolk granules of maturing oocytes when they attained a diameter of 50 μm. Extraction of the protein and its estimation by radioimmunoassay in tissues from reproducing and reproductively inactive (virgin) snails suggest that ferritin is synthesized extragonadally and transported in the blood to maturing oocytes in the ovotestis. Ferritin was also found in the digestive gland and in the mantle, which contains pore cells. Mantle ferritin levels fluctuated with reproductive activity. The possibility that pore cells play a role in regulating vitellogenic ferritin is discussed.
Action d'extraits d'épithélium cicatriciel sur la régénération des doigts chez Rana ridibunda adulte: étude histologique et biométrique
Authors: Revardel J.-L. , Aoussi S. , Chapron C.
Published: August 2008

In Rana ridibunda, the frequency of digit regeneration and the size of the new growths, which depend on the nature of the injured tissues, can be increased experimentally by injecting extracts from the scar epithelium. As in untreated digits, a blastema never forms and the scar epithelial extracts trigger the formation of chondrogenesis centers or stimulate their growth. Ordinary epidermis does not take part in this activity which is thus specific and seems to depend on proteolytic enzymes of the same type as collagenases. Anurans do not usually regenerate or if they do, it is in a rudimentary fashion; this is not due to the nonfunctional state of their scar epithelium, but rather to its insufficient activity and to the predominance of scar fibrous conjonctive tissue (fibroblastic) over chondroblastic tissue, the only type that can promote regeneration.[Journal translation]
Life histories, production, and microdistribution of two caddisflies (Trichoptera) in a Rocky Mountain stream
Authors: Ogilvie Gael A. , Clifford Hugh F.
Published: August 2008

This paper reports results of a 2-year study of the caddisflies Oligophlebodes zelti (Limnephilidae) and Neothremma alicia (Uenoidae) in a first-order Rocky Mountain stream of southern Alberta. The Oligophlebodes population had a univoltine cycle: eggs were oviposited in July and August and hatched in about 20 days, and the larvae grew rapidly during the remainder of the ice-free season. Larvae overwintered in the fourth larval instar and molted to the fifth instar the following spring. Pupation occurred in June, and adults started emerging in mid-July. Annual production for the O. zelti population was 116 mg∙m−2∙year−1. The Neothremma population had a 2-year cycle. Eggs apparently hatched after freeze-up. Larvae overwintered in the second instar. Most of the population achieved the third instar by the following July and the fourth instar by August, and spent the second winter in either the fourth or fifth instar. There was about a 3-week prepupal stage the following July and then emergence in July and August. Annual production for the N. alicia population was 103 mg∙m−2∙year−1. Oligophlebodes zelti and N. alicia larvae fed mainly on fine particulate organic matter and diatoms. Both O. zelti and N. alicia larvae were found on rocks only in fast water areas, but the two populations did not inhabit the same riffles. The riffles inhabited by O. zelti were wider with lower slopes and water velocities than riffles dominated by N. alicia larvae. Correlation analysis, using several parameters, indicated that total periphyton of the rocks might be a major factor accounting for O. zelti's distribution. The microdistribution of the N. alicia population was not correlated with any food source.
A new subfamily, Cydnodromellinae, in the family Phytoseiidae (Acari: Gamasina)
Authors: Chant D. A. , Yoshida-Shaul E.
Published: August 2008

A new subfamily, Cydnodromellinae, is proposed in the family Phytoseiidae. Members of the subfamily are characterized by the unique chaetotaxy of the podoscutum, which has five pairs of setae (j3, z2, z4, s4, s6) on its lateral area, with seta z3 absent. There are two genera in this new subfamily. Platyseiella Muma is monotypic, represented by the type-species, P. platypilis (Chant). Cydnodromella Muma includes three species groups and six species: the negevi group (C. negevi (Swirski and Amitai) comb.nov.), the pilosus group (C. pilosus (Chant), type-species of the genus Cydnodromella), and the alveolaris group (C. alveolaris (De Leon) comb.nov., C. borinquensis (De Leon) comb.nov., C. sanictus (De Leon) comb.nov. and C. tunapunensis (De Leon) comb.nov.). Galendromimus Muma and Typhlodromus (Galendromimus) Muma sensu van der Merwe are designated as junior synonyms of the genus Cydnodromella and Cydnoseius cordiae Muma, Typhlodromus medanicus El Badry, and T. zaheri El Badry are designated as junior synonyms of C. negevi. Systematic concepts pertaining to the species in the two genera are reviewed, and descriptions of each genus, species group, and species are given. Keys to the adult females of the species groups in the genus Cydnodromella and to the species in the alveolaris group are provided.
Prédation de mollusques dulçaquicoles par les larves malacophages de Tetanocera ferruginea Fallen, 1820 (Diptera, Sciomyzidae)
Authors: Manguin Sylvie , Vala Jean Claude , Reidenbach Jean Marie
Published: August 2008

The range of prey of Tetanocera ferruginea larvae has been established from the freshwater snails living in one of its biotopes. Three predator–prey systems were examined, using the most common prey species of the larvae: Planorbis contortus, Lymnaea palustris, and Physa acuta. Analysis in terms of numbers and biomass of ingested prey has revealed the influence of morphology, ethology, and size of prey in these systems. By employing an appropriate dimensional connection with the prey, the data show that T. ferruginea larvae consume, on average, 45 Planorbis, 28 Lymnaea, or 30 Physa. As the Planorbis biomass is less than that of the two other species, the larvae partly compensate by eating more of them and so reduce the differences between the biomass of each prey eaten. When mollusks of similar biomass are used, the observed differences in terms of number of prey and biomass are not significant. In all cases, because of the amount and diversity of mollusks killed during its larvae cycle, T. ferruginea appears to be a most effective predator.
Some ultrastructural aspects of Crithidia guilhermei n.sp. isolated from Phaenicia cuprina (Diptera: Calliphoridae)
Authors: Soares Maurilio J. , Brazil Reginaldo P. , Tanuri Amilcar , Souza Wanderley de
Published: August 2008

A flagellate trypanosomatid was isolated from the fly Phaenicia cuprina captured in Rio de Janeiro, Brazil. It grows well in liver infusion – trypticase medium, in the form of choanomastigotes, typical of the genus Crithidia. Morphometrical data obtained at the light microscopical level indicated that the new isolated Crithidia is smaller than Crithidia luciliae, a parasite isolated from Phaenicia sericata. Transmission electron microscopy of thin sections revealed that this trypanosomatid has a flagellar pocket divided into two compartments, one basal and the other apical, separated by a region of attachment of the flagellum to the cell body. The attachment region was characterized in freeze-fracture replicas. The flagellate has a compact kinetoplast DNA network. As in endosymbiote-containing trypanosomatids previously described, no subpellicular microtubules were seen in the regions where the mitochondria touched the plasma membrane, although no endosymbiotes were found in this flagellate. Electrophoretic mobility of six enzymes showed that the parasite could not be grouped in any of the isoenzymic pattern groups of other Crithidia spp. These observations indicate that the trypanosomatid isolated from P. cuprina is a new species of Crithidia. The flagellate is described as Crithidia guilhermei n.sp.
Nuclear glycogen and lipid in hepatocytes of a fish, Rivulus ocellatus marmoratus
Authors: Thiyagarajah Arunthavarani , Grizzle John M.
Published: August 2008

Prevalence and contents of nuclear deposits in hepatocyte nuclei of laboratory-reared Rivulus ocellatus marmoratus were determined. Hepatocyte nuclei containing beta glycogen particles, lipids, or both glycogen and lipid occurred in 45% of larvae, 11% of juveniles, and 75% of adults. In fish with vacuolated nuclei, mean percentages of hepatocytes with vacuolated nuclei increased with age from 2% in larvae to 90% in adults.
Neural control of the anorexia-cachexia syndrome
Authors: Laviano Alessandro , Inui Akio , Marks Daniel L. , Meguid Michael M. , Pichard Claude , Rossi Fanelli Filippo , Seelaender Marilia
Published: August 2008

The anorexia-cachexia syndrome is a debilitating clinical condition characterizing the course of chronic diseases, which heavily impacts on patients' morbidity and quality of life, ultimately accelerating death. The pathogenesis is multifactorial and reflects the complexity and redundancy of the mechanisms controlling energy homeostasis under physiological conditions. Accumulating evidence indicates that, during disease, disturbances of the hypothalamic pathways controlling energy homeostasis occur, leading to profound metabolic changes in peripheral tissues. In particular, the hypothalamic melanocortin system does not respond appropriately to peripheral inputs, and its activity is diverted largely toward the promotion of catabolic stimuli (i.e., reduced energy intake, increased energy expenditure, possibly increased muscle proteolysis, and adipose tissue loss). Hypothalamic proinflammatory cytokines and serotonin, among other factors, are key in triggering hypothalamic resistance. These catabolic effects represent the central response to peripheral challenges (i.e., growing tumor, renal, cardiac failure, disrupted hepatic metabolism) that are likely sensed by the brain through the vagus nerve. Also, disease-induced changes in fatty acid oxidation within hypothalamic neurons may contribute to the dysfunction of the hypothalamic melanocortin system. Ultimately, sympathetic outflow mediates, at least in part, the metabolic changes in peripheral tissues. Other factors are likely involved in the pathogenesis of the anorexia-cachexia syndrome, and their role is currently being elucidated. However, available evidence shows that the constellation of symptoms characterizing this syndrome should be considered, at least in part, as different phenotypes of common neurochemical/metabolic alterations in the presence of a chronic inflammatory state.
α-Adrenoceptor blockade modifies neurally induced atrial arrhythmias
Authors: Richer Louis-Philippe , Vinet Alain , Kus Teresa , Cardinal René , Ardell Jeffrey L. , Armour John Andrew
Published: August 2008

Our objective was to determine whether neuronally induced atrial arrhythmias can be modified by α-adrenergic receptor blockade. In 30 anesthetized dogs, trains of five electrical stimuli (1 mA; 1 ms) were delivered immediately after the P wave of the ECG to mediastinal nerves associated with the superior vena cava. Regional atrial electrical events were monitored with 191 atrial unipolar electrodes. Mediastinal nerve sites were identified that reproducibly initiated atrial arrhythmias. These sites were then restimulated following 1 h (time control, n = 6), or the intravenous administration of naftopidil (α1-adrenergic blocker: 0.2 mg/kg, n = 6), yohimbine (α2-adrenergic blocker: 1 mg/kg, n = 6) or both ( n = 8). A ganglionic blocker (hexamethonium: 1 mg/kg) was tested in four dogs. Stimulation of mediastinal nerves sites consistently elicited atrial tachyarrhythmias. Repeat stimulation after 1 h in the time-control group exerted a 19% decrease of the sites still able to induce atrial tachyarrhythmias. Hexamethonium inactivated 78% of the previously active sites. Combined α-adrenoceptor blockade inactivated 72% of the previously active sites. Bradycardia responses induced by mediastinal nerve stimulation were blunted by hexamethonium, but not by α1,2-adrenergic blockade. Naftopidil or yohimbine alone eliminated atrial arrhythmia induction from 31% and 34% of the sites (similar to time control). We conclude that heterogeneous activation of the intrinsic cardiac nervous system results in atrial arrhythmias that involve intrinsic cardiac neuronal α-adrenoceptors. In contrast to the global suppression exerted by hexamethonium, we conclude that α-adrenoceptor blockade targets intrinsic cardiac local circuit neurons involved in arrhythmia formation and not the flow-through efferent projections of the cardiac nervous system.
Magnetic Resonance Imaging and Its Usage in Representative Areas of Neurobiological Research
Authors: Shi Chun , Kwong W.H. , Forster E. Lucy , Cho Eric Y.P.
Published: August 2008

This paper summarizes the various methodologies used in magnetic resonance imaging (MRI) and presents the background logic behind these methodologies. The usage of MRI in the study of human subjects and animals is discussed and highlighted. Select examples of animal MR images are presented.
Gastric Inflammatory Fibroid Polyp Treated by Endoscopic Submucosal Dissection
Authors: Hattori Y. , Kobayashi S. , Takahashi H. , Yoneda M. , Inamori M. , Abe Y. , Kubota K. , Saito S. , Nakajima A.
Published: August 2008

The endoscopic examination of a 64-year-old male patient revealed a gastric submucosal tumor in the anterior wall of the gastric antrum. The lesion increased in diameter to 25 mm and was resected completely with endoscopic submucosal dissection (ESD). Histological examination of the submucosal tumor gave a diagnosis of an inflammatory fibroid polyp (IFP). It is suggested that ESD may be an effective and safe therapy for gastric submucosal tumors.
Prolongation of Survival and Improvement in Performance Status following Palliative Chemotherapy in Gastrointestinal Cancer Patients with a Poor Performance Status
Authors: Shitara Kohei , Munakata Masaki , Kasai Masaharu , Muto Osamu , Sakata Yuh
Published: August 2008

Background: The prognosis of advanced gastrointestinal cancer, especially in patients with poor performance status (PS), is generally dismal. Patients with PS 3–4 are almost ineligible for participation in clinical studies. Patients and Methods: From June 2000 to February 2007, 116 patients with poor PS (PS 3 = 73 and PS 4 = 43) were treated with chemotherapy. Retrospective analysis was performed. Results: Of the 107 patients with at least one measurable lesion, a partial response was obtained in 15 patients (14.0%). Of 65 patients with ascites and/or pleural effusion, 12 patients achieved decreased fluid accumulation. A decline in tumor markers was observed in 30 patients. As a result, 38 patients (32.7%) achieved tumor response, a decrease in fluid accumulation or a decline in tumor markers (responders), which resulted in a survival benefit compared to the other 78 patients without effect (6.9 vs. 2.2 months, p < 0.001). PS improvement was seen in 16 patients (13.8%). Conclusions: The results suggest that chemotherapy may be beneficial in gastrointestinal cancer patients with poor PS, as demonstrated by a certain degree of improvement in PS and survival in responders. Further study is required to confirm the benefit of chemotherapy in this patient population.
Inhibition of Apoptotic Signaling and Neointimal Hyperplasia by Tempol and Nitric Oxide Synthase following Vascular Injury
Authors: Jagadeesha Dammanahalli K. , Miller, Jr. Francis J. , Bhalla Ramesh C.
Published: August 2008

Objectives: We hypothesized that redox-mediated apoptosis of medial smooth muscle cells (SMC) during the acute phase of vascular injury contributes to the pathophysiology of vascular disease. Methods: Apoptosis of medial SMC (1–14 days following balloon injury) was identified in rat carotid arteries by in situ DNA labeling. NADPH-derived superoxide and expression of Bcl-xL, Bax, caspase-3 and caspase-9 were assessed. The antioxidant tempol was administered in drinking water throughout the experimental period, and local adenoviral-mediated gene transfer of eNOS was performed prior to vascular injury. Results: Balloon injury increased NADPH-dependent superoxide production, medial SMC apoptosis, Bax-positive medial SMC index, Bax/Bcl-xL ratio, and caspase-3 and caspase-9 expression in the injured arteries. Treatment with tempol or eNOS gene transfer decreased superoxide levels and medial SMC apoptosis, with a concomitant increase in medial SMC density. Inhibition of superoxide was associated with a decreased Bax/Bcl-xL ratio, and caspase-3 and -9 expression. Tempol treatment and eNOS gene therapy significantly reduced neointima formation. Conclusion: Vascular generation of reactive oxygen species participates in Bax activation and medial SMC apoptosis. These effects likely contribute to the shedding of cell-cell adhesion molecules and promote medial SMC migration and proliferation responsible for neointimal hyperplasia.