bluuebunny/crossref_metadata_2025_split huggingface dataset:
Host location by the Japanese beetle: Evidence for a key role for olfaction in a highly polyphagous insect
Authors: Ahmad Sami 
Published: June 2005

AbstractOlfaction plays a key role in host location and possibly also in host preference in a highly polyphagous insect, the Japanese beetle, Popillia japonica Newman. Moreover, this study also shows for the first time that impairment in olfaction by antennectomy affects feeding intensity. This suggests probable integration of olfactory and gustatory inputs in eliciting maximal/optimal feeding response.
Cell interactions and actin synthesis in mammalian oocytes
Authors: Osborn J. C. , Moor R. M. 
Published: June 2005

AbstractIn this study, we have examined the profiles of proteins synthesized by mammalian oocytes in the presence and absence of cumulus cells. The results show that the patterns of protein synthesis are broadly similar in cumulus‐enclosed and denuded oocytes, but that as a consequence of removing the cumulus cells, the presence of a 45,000‐dalton band is greatly reduced. This band, identified by comigration studies on two‐dimensional polyacrylamide gels as actin, is strongly synthesized in both isolated cumulus cells and in oocytes labeled in the presence of cumulus cells, but is only weakly synthesized by oocytes incubated in the absence of cumulus cells. We suggest that the presence of newly synthesized actin in the oocyte is dependent upon cellular cooperation between the cumulus cells and oocytes.
Presence and possible function of root effect hemoglobins in fishes lacking functional swim bladders
Authors: Ingermann Rolf L. , Terwilliger Robert C. 
Published: June 2005

AbstractThe adult hemoglobins of 15 species of teleost and the midgestation fetal hemoglobin of the seaperch Embiotoca lateralis show a pronounced decrease in oxygen‐carrying capacity at low pH, a Root effect. All of these fishes lack a functional swim bladder, which is generally thought to be the likely site of Root effect hemoglobin function. All of the teleosts examined, including the fetal sea perch, however, have a choroid rete, a structure that is proposed to be involved in oxygen secretion to the eye. The data are inconsistent with the generalization that only fishes with swim bladders possess Root effect hemoglobins, and that the only function of Root effect hemoglobins is in the secretion of oxygen to a swim bladder. The data for the fishes examined in this study suggest that a better correlation may exist between Root effect hemoglobins and the presence of a choroid rete. This is consistent with the hypothesis that Root effect hemoglobins may be involved in the physiology of the eye in many fishes.
Characterization of glycoprotein antifreeze biosynthesis in isolated hepatocytes from Pagothenia borchgrevinki
Authors: O'Grady Scott M. , Clarke Andrew , DeVries Arthur L. 
Published: June 2005

AbstractIncorporation of 14C‐leucine and 3H‐alanine into TCA‐precipitable protein, TCA‐soluble protein, and antifreeze glycoproteins (AFGP) was measured in isolated hepatocytes from Pagothenia borchgrevinki Boulenger following acclimation to −1.5°C and + 4°C. The rate of 3H‐alanine incorporation into AFGP followed Michaelis‐Menten kinetics with a Vmax of 4.8 nM·mg protein−1·h−1 at −1.5°C and 7.5 nM·mg protein−1·h−1 at + 4°C. Km values were 27.8 μM and 41.7 μM at −1.5°C and + 4°C, respectively. Incorporation of 14C‐leucine into TCA‐precipitable protein also showed Michaelis‐Menten kinetics with a Vmax of 20 nM·mg protein −1·hr−1 at −1.5°C and 32.3 nM·mg protein −1·hr−1 at + 4°C. Km values were 83.3 μM at −1.5°C and 125 μM at + 4°C. AFGP synthesis was monitored over a 120‐h period by radioimmunoassay in cultures of hepatocyes from cold acclimated fish (− 1.5°C) incubated at both − 1.5°C and + 4°C. The estimated Q10 for AFGP from these data is 3.23. Polyacrylamide gel electrophoresis of antifreeze glycoproteins produced by isolated hepatocytes showed that all four antifreeze fractions normally present in the serum of P. borchgrevinki are also synthesized by isolated hepatocytes. The two major conclusions from these experiments were that 1) P. borchgrevinki, unlike many northern fishes, does not show thermal acclimation, and 2) environmental factors responsible for modification of peptide antifreeze synthesis in northern fishes do not elicit changes in AFGP synthesis in P. borchgrevinki.
Collagens from the skin and cartilage of the larval salamander Ambystoma tigrinum
Authors: Smith Gerald N. , Linsenmayer Thomas F. 
Published: June 2005

AbstractThe major collagens of larval salamander (Ambystoma tigrinum) skin and cartilage were purified and characterized by CM‐cellulose chromatography and amino acid analysis of the component α chains. The collagens are similar to type I (skin) and type II (cartilage) collagens of birds and mammals. The type I molecule has the chain composition (α1)2α2, and the type II molecule is an (α1)3 molecule. Both collagens have lower levels of proline hydroxylation than the collagens isolated from homoiotherms, and generally higher serine contents. The type II collagen molecule has about half of its lysine residues hydroxylated, as in cartilage collagens of other species. Cyanogen bromide digestion of the component α chains followed by CM‐cellulose chromatography or SDS gel electrophoresis of the peptides confirms that each chain is a different gene product and allows identification of the collagens in this species. Similar collagens were isolated from newt (Notophthalmus viridescens) tissues by pepsin extraction and fractional salt precipitation. These data will allow more effective utilization of the regenerating salamander limb for studies of collagen metabolism during regeneration.
The effect of primary and secondary immunization on the lymphoid tissues of the carp, Cyprinus carpio L
Authors: Secombes Christopher J. , Manning Margaret J. , Ellis Anthony E. 
Published: June 2005

AbstractMirror carp immunized with human gamma globulin (HGG) in Freund's complete adjuvant (FCA) show a proliferative response involving cells whose cytoplasm stains deep red with methyl green‐pyronin (pyroninophilic cells). This response occurs particularly in the haemopoietic parenchyma of the pronephros and mesonephros. It peaks at week 3, with the formation of clusters of pyroninophilic cells in the pronephros. Immunization with Aeromonas salmonicida elicited a less intense pyroninophilic response but caused a larger increase in pigment‐containing cells. After a secondary immunization with HGG in FCA, a distinct response was observed in the spleen: Pyroninophilic cells collected within the ellipsoid sheaths in large numbers and formed nodules. The reticulum of such nodules acquired spherical proportions and resembled the white pulp reticulum of the tetrapod spleen. The roles of such pyroninophilic cells and the possibility that aggregations of them may be functionally analogous to homoiotherm germinal centres are discussed.
Control of contour feather growth of Japanese quail
Authors: Honda H. , Tanaka Kumiko , Minamino T. , Konishi T. 
Published: June 2005

AbstractGrowth of a contour feather on a dorsal spinal tract of Japanese quail was investigated using a logistic model, in which feather length is determined by two factors, growth rate and growth period. Final feather lengths were constant under most experimental conditions including those under which the growth rate decreased while the growth period increased. Another experimental condition was discovered in which a feather elongated owing to an increase in growth period.Once a feather had fully grown, its length remained constant. After plucking a feather, a new feather grew and its final length was correlated with the old one. Shortening a growing feather by cutting off a distal part did not affect its growth pattern. In addition, shortening a fully grown feather by cutting off the distal part did not activate its follicle. Plucking a feather during growth stopped and erased the present growing phase and initiated feather growth from the beginning to form a complete feather. Repetition of plucking four or five times did not affect the final length of a feather, but did decrease the growth rate, which was complemented by an elongation of the growth period. Feather formation under a short photoperiod condition (8L:16D) resulted in a longer feather which resulted from elongation of the growth period while the growth rate remained constant.
Hydromineral balance in the chick embryo: Effects of hypophysectomy
Authors: Murphy Michael J. , Brown Stephen C. , Brown Patricia Stocking 
Published: June 2005

AbstractThe developing chick embryo exhibits a regular pattern of accumulation and reabsorption of fluid in its extraembryonic compartments. Fluid volume (measured by dye dilution) peaks at Day 14 in both the allantois (12.4 ml) and the amnion (5.1 ml). The standard experimental procedure of removing 2 ml of albumen at 33–36 hr of incubation does not alter this pattern, but leads to a maximum decrease in fluid volume of ca. 1 ml in both amniotic and allantoic compartments. Although [Na] and [Cl] remain essentially constant in the serum, they steadily decrease in the allantois (remaining substantially below serum levels). In the amnion, [Cl] is maintained above that of serum, whereas [Na] falls below serum [Na] by Day 14. In the Day 12 (stage 38) embryo, hypophysectomy (HX) causes a substantial increase in the allantoic fluid volume and [Na] and [Cl], thus resulting in a 166% increase in total Na and Cl over that of sham‐operated embryos. By contrast, HX did not alter amniotic fluid volume, although it did decrease [Na] and to a lesser degree, [Cl]. Serum [Na], but not [Cl], was reduced by HX. HX abolished the normally steep ionic gradients maintained between the allantois and both serum and amnion. Thus, the most dramatic effects of HX at Day 12 are on the allantois, which accumulates both Na and Cl at the expense of the amnion and serum. This suggests that pituitary hormones may normally act by Day 12 to reduce urinary volume and electrolyte excretion and/or to increase fluid and electrolyte reabsorption from the allantois.
Development of embryonic chick oviducts in organ culture under the influences of steroid hormones
Authors: Kiell Charles S. , Cohen Ira T. , Fell Paul E. 
Published: June 2005

AbstractExplanted oviducts from 13‐ and 16‐day embryonic female chicks responded to estradiol (1 to 4 μg/ml) in the culture medium by forming a thickened epithelium folded into crypts and containing goblet cells and by development of the stroma. In medium containing 3 μg/ml estradiol and 0.125 μg/ml hydrocortisone, 13‐day embryonic oviducts exhibited further development: The columnar epithelial cells formed cilia and tubular glands were formed.
In vivo and in vitro effect of cold on the degree of polymerization of tubulin in toad brain and testis
Authors: Lopez Luis A. , Bertini Francisco 
Published: June 2005

AbstractThe tubulin of both brain and testis of the toad Bufo arenarum was partially depolymerized when the animals were maintained on ice for 90 minutes or 17 hours. Recovery of the animals at room temperature restored the normal degree of polymerization in both organs. Normalization of the polymerization degree also occurred in organs separated from cooled animals and incubated in vitro for 90 minutes at 20°C. When the organs were cooled in vitro, only testicular tubulin underwent depolymerization, and in a degree similar to that occurring by incubation at 20°C. The results suggest that the mechanisms regulating tubulin depolymerization in vivo are different from those taking place in vitro.
Western Fence Lizard (Sceloporus occidentalis) chemical signals. III. An experimental ethogram of conspecific body licking
Authors: Duvall David 
Published: June 2005

AbstractThe loci and frequency of conspecific body licking actions of naturally breeding, adult western fence lizards, Sceloporus occidentalis biseriatus, were catalogued and analyzed in an experimental ethogram procedure. The purpose of the study was to begin to localize regions of the western fence lizard body that might exude or carry conspecific chemical signals, or pheromones, important in social encounters of close physical proximity. Among pairs of males, females, and males and females, male stimulus lizards were licked more than stimulus females on (1) the head and face and (2) the flank‐back region, and this was exhibited equally by both male and female experimental lizards (each pair was composed of an experimental and stimulus lizard). Although male and female stimulus animals were licked equally on their legs, experimental females exhibited higher levels of this action than did experimental males. A few tail licks occurred, but no differences of any type were obtained. The results suggest the possibility that pheromones carried on, or exuded from, certain fence lizard body regions, such as the head and face, for example, may play a releasing or eliciting function in social encounters of close physical proximity. Such cues probably are detected by the tongue‐vomeronasal system.
The adaptive significance of the reversed bohr and root shifts in blood from the marine gastropod, Buccinum undatum
Authors: Brix Ole 
Published: June 2005

AbstractThe adjustments of blood respiratory properties to hypoxic conditions (PWO2 = 30 Torr) have been investigated in relation to salinity acclimation in the marine prosobranch, Buccinum undatum. (1) In whole blood the reversed Bohr effect and the cooperativity of O2 binding are not influenced by acclimation history. (2) Blood from high‐salinity (35%) animals is isoosmotic to the ambient water under normoxic conditions (PWO2 = 150 Torr), but hypoosmotic under hypoxic conditions by a regulated decrease in the Cl− ion concentration of about 90 mM. The lower [Cl−] induces, via the reversed Root effect, an approximate doubling of the amount of hemocyanin‐bound oxygen, when blood pCO2 is increased in the range 1 to 8 Torr. (3) Blood from low‐salinity (20%) animals is also isoosmotic to the ambient water under hypoxic conditions, and the reversed Root effect is present under both normoxic and hypoxic conditions. (4) At both high and low salinity no change in blood hemocyanin concentration is seen in hypoxiaacclimated animals.
Roles of ectodermal and endodermal epithelial cells in hydra morphogenesis: Construction of chimeric strains
Authors: Wanek Nancy , Campbell Richard D. 
Published: June 2005

AbstractA method is described for constructing chimeric hydra that consist of ectoderm from one strain of hydra and endoderm from a different strain. A ring of vitally stained tissue (ectoderm and endoderm) is grafted into an unmarked polyp. Differential movement of the ectoderm and endoderm eventually results in chimeric regions which are visible as marked ectoderm overlying unmarked endoderm and unmarked ectoderm overlying marked endoderm. These chimeric regions are then excised and each is allowed to regenerate, forming a whole chimeric animal. Isolated chimeric regions smaller than 0.5 mm in length were grafted into nitrogen mustard treated animals as hosts for in vivo culturing. Reciprocal chimeras between the 40L strain of H. magnipapillata (40L) and H. attenuata (Ha) were used to illustrate the effectiveness of the method for constructing chimeras. These two strains are different in body morphology, size, and color. The [40L ectoderm/Ha endoderm] chimera has 40L shape but is the size and color of Ha. The [Ha ectoderm/40L endoderm] chimera resembles Ha in body shape but is the size and color of 40L. The stability of these traits indicates that the original parental lineage of the epithelial cells is maintained in the chimeric hydra.
Effect of augmentation of nerve supply upon limb regeneration in the chick embryo
Authors: Fowler Ira , Sisken Betty F. 
Published: June 2005

AbstractLimb regeneration was induced in 4‐day chick embryos by implanting stage 15 neural tube into the amputated stump of the limb. In control animals, amputation alone or amputation with implant of either notochord or somites resulted in development of proximal wing segments only. In experimental animals, more than one‐fourth of the animals containing viable neural tube implants developed proximal, middle, and distal limb segments. These regenerated limb segments contained muscle groups, cartilage models, and nervous structures that approximated the normal situations. Since some new parts regenerated in more than one‐fourth of the cases, it may be concluded that augmentation of nerve supply is an effective method of inducing regeneration in limbs of chick embryos. Volume measurements of the neural tube implant indicate that a “critical mass” of nerve tissue may be necessary for regeneration to occur.
Studies on cockroach flight: The role of continuous neural activation of non‐flight muscles
Authors: Fourtner C. R. , Randall J. B. 
Published: June 2005

AbstractThe primary purpose of this study was to identify the muscles active during flight and determine their temporal relationships in the flight‐cycle, thereby laying the foundations for further investigations of the neural control of flight in the cockroach. The wing‐beat frequency of tethered roaches and the frequency of the flight‐cycle in restrained animals was similar, varying between 23 and 30 beats/second. Intracellular recordings of metathoracic and metacoxal muscle were made simultaneously with electromyograms from the elevators of the wing. Muscles 155, 157, 161, 162, 163, 177A, and 174‐6 were active near the onset of elevator activity; muscles 153, 154, 164, 165, 167, 169, and 177C were active approximately 180° out of phase with the elevators. Muscles 177A and 177C, bifunctional in nature, act as antagonists during flight and as synergists to extend the femur. Since the femur is held flexed during flight, the activity of the femoral flexors, 181A‐C and 182C, was determined during flight. 181A and B showed a bimodal phase distribution while 181C and 182C was almost continuously active during flight. Therefore, the flight‐motor‐program reciprocally drives the elevators and depressors and can continuously drive the motor‐neuronal pool operating the femoral flexor. This continuous drive fixes the femur and permits 177A and 177C to act on the thoracic box.
Time course of changes in fatty acid composition of gills and liver from rainbow trout (Salmo gairdneri) during thermal acclimation
Authors: Sellner Peggy A. , Hazel Jeffrey R. 
Published: June 2005

AbstractRainbow trout (Salmo gairdneri), acclimated to 5°C or 20°C, were reacclimated to water of the opposite temperature. The time course of alterations in fatty acid composition of microsomes from gills and liver was monitored over a 28‐day period. Two to six days were required for maximum changes in fatty acid levels with acclimation to 20°C, whereas 10—17 days were required in the opposite direction. Fatty acids from gill microsomes had lower U/S (ratio of unsaturates to saturates) and UI (unsaturation index) and a shorter average chain length than liver microsomes; these differences were preserved with acclimation. In both tissues the U/S, UI, and chain length increased with cold adaptation and decreased with warm adaptation. In gill microsomes, changes in UI and U/S were due primarily to altered levels of saturated fatty acids and 20:4 (n‐6) and 20:5 (n‐3). The latter two acids, products of the Δ5 desaturation step in PUFA biosynthesis, also contributed to the changes in unsaturation indexes were initially mediated by large but transient changes in levels of saturates and monoenes, whereas changes in polyunsaturated fatty acids of the n‐6 and n‐3 families were delayed 3—6 days. Thus, changes in fatty acid composition that accompany acclimation to a different temperature can be resolved into those metabolic reactions (e.g., Δ5 desaturation) that are of major importance and, in the liver, into temporally more than one mechanism (e.g., altering monoenes and PUFA at different times).
Urea cycle enzymes and glutamate dehydrogenase in Xenopus laevis and Bufo viridis adapted to high salinity
Authors: Lee Anina R. , Silove Michelle , Katz Uri , Balinsky John B. 
Published: June 2005

AbstractXenopus laevis was adapted stepwise to 600 m osmolar sodium chloride. After adaptation, the level of argininosuccinate lyase was raised 9‐fold, carbamoylphosphate synthetase 6‐fold, and ornithine carbamoyltransferase and arginase 3‐fold. Liver glutamate dehydrogenase was also raised 5‐fold; kidney glutamate dehydrogenase was unchanged. In Bufo viridis similarly adapted, there was a 5‐fold increase in argininosuccinate lyase. When Xenopus laevis was adapted to 600 m osmolar sucrose, there was only an increase in argininosuccinate lyase, and that was only 2.4‐fold. This indicates that the increases in urea cycle enzymes are at least in part responses to sodium chloride rather than just to osmotic stress.
Muscle protein phenotypes and the probable evolutionary origin of a unisexual fish, Poecilia formosa, and its triploid derivatives
Authors: Monaco Paul J. , Rasch Ellen M. , Balsano Joseph S. , Turner Bruce J. 
Published: June 2005

AbstractSeveral species‐specific proteins have been identified by polyacrylamide gel electrophoresis (PAGE) of skeletal muscle extracts from the diploid gynogen, Poecilia formosa, its related triploid unisexuals, and their sympatric, bisexual species, P. mexicana and P. latipinna. These water‐soluble, low molecular weight proteins (7,000‐13,000) comigrate with a fraction of purified rabbit parvalbumin on nondenaturing gels and show staining properties similar to rabbit parvalbumins. The electrophoretic patterns of these muscle proteins provide a set of distinctive phenotypic markers for each of the host species involved in naturally occurring breeding complexes with P. mexicana × P. latipinna show no evidence of sexual dimorphisms. Furthermore, the hybrid phenotypes are those that would be predicted from appropriate combinations of parental alleles at three gene loci. The patterns found by PAGE for several generations of pedigreed stocks of P. formosa show strictly matroclinous inheritance of a characteristic muscle protein phenotype and coupled with the electrophoretic patterns of several enzymic proteins reflect the probable hybrid origin of this diploid unisexual. Finally, paternal contributions by P. mexicana to the hybrid genome of triploid unisexuals are clearly demonstrated by comparative analyses of muscle protein phenotypes for P. formosa and its contemporary host species. Our identification of distinctive phenotypic markers in the muscle proteins of several poeciliid species involved in unisexual‐bisexual breeding complexes provides an important new tool for further studies on the adaptive significance of unisexuality, hybridization, and fixed heterozygosity in the evolutionary biology of these fishes.
Peptidase lsozymes of the leopard frog Rana pipiens: Properties and genetics
Authors: Wright David A. , Richards Christina M. 
Published: June 2005

AbstractThe substrate specificity of five peptidases in tissues of the leopard frog, Rana pipiens, corresponds to mammalian peptidases (Pep) A, B, C, D, and S. The inheritance of electrophoretic variants of Pep A, B, C, and D verifies the genetic basis of the variants and the control of the enzymes by separate genetic loci. Electrophoretic patterns of heterozygotes suggest that Pep A, B, and D are dimers, whereas Pep C has a monomer structure. The tissue distribution and developmental patterns suggest that frog peptidases are subject to cellular regulation. Tests of genetic linkage show independent assortment for Pep A and Pep C and for Pep C and Pep D. Pep C is closely linked to superoxide dismutase‐1 (6.87% recommbination), and Pep B is linked to mannose phosphate isomerase (30.4% recommbination).