| [phylogenetic studies on some japanese amphibia by means of immunoelectrophoresis. ii. relationships of some amphibians to japanese pond frogs (author's transl)]. | since the japanese pond frogs (rana nigromaculata and r. brevipoda) are known to be very closely allied with each other in morphological, ecological, physiological or immunological characters, the phylogenetical relationships between the japanese pond frogs and other 10 species of japanese amphibians were investigated by means of immunoelectrophoretic analysis of liver extract. the results obtained are as follows: (1) there are conservative antigens which are commonly found in all species of anu ... | 1978 | 631194 |
| [phylogenetic studies on some japanese amphibia by mean of immunoelectrophoresis. i. relationships of some frogs and newt to toad (author's transl)]. | the phylogenetic relationship among toad, frogs and newt from japan was investigated by means of immunoelectrophoresis. homologous, heterologous and non-identity reactions between rabbit anti-bufo bufo antiserum and antigen from each of 13 species and 2 subspecies of japanese amphibia were examined. the number and positions of arcs appeared in these reactions were compared. the relationship observed in the comparison well coincided with the classification of the upper taxa of amphibia; viz 1) hy ... | 1975 | 808417 |
| cytological and microspectrophotometric analysis of mesodermalized explants of triturus gastrula ectoderm. | using isolated presumptive ectoderm of the newt (triturus pyrrhogaster) embryos as a reactor and extract of rat bone marrow as a mesodermal inductor, changes of cell number and mitotic index of the reactor cells were studied. in early stages of cultivation the increase in cell number in the mesodermalized ectodermal piece was slower than in the non-mesodermalized epidermal piece; but after 24 h it showed abrupt increase and reached a cell population equal to that of the control at 48 h of cultiv ... | 1976 | 978130 |
| architecture of the marrow vasculature in three amphibian species and its significance in hematopoietic development. | architecture of the bone marrow vasculature, particularly that of the femur, was analyzed in three amphibian species in relation to the early phylogeny of marrow hematopoiesis. a dye-injection method and histological techniques, including both serial sectioning and reconstruction methods, were used for this purpose. from these observations the following conclusions may be drawn. (1) marrow hematopoiesis is absent from the femur of the urodelan (triturus pyrrhogaster) and appears first in the fem ... | 1976 | 1083670 |
| [immunocytochemical studies on the pancreatic endocrine cells in the japanese newt (cynopus pyrrhogaster)]. | pancreatic endocrine cells were examined by light and electron microscopic immunocytochemistry to discuss the co-localization of peptides in one cell type. a cells were irregular in shape with an occasional long cytoplasmic process, and contained glucagon-immunoreactive granules with various contours. these granules were 160-300nm in diameter with various density, and also immunoreactive to anti-human pancreatic polypeptide (pp) serum. a part of them were further immunoreactive to anti-somatosta ... | 1992 | 1360408 |
| presence of d-aspartate oxidase and free d-aspartate in amphibian (xenopus laevis, cynops pyrrhogaster) tissues. | 1. this paper is the first report on the presence of d-aspartate oxidase activity and free d-aspartate in the amphibian tissues. 2. the presence of d-aspartate oxidase activity in tissues of clawed toad (xenopus laevis) and japanese newt (cynops pyrrhogaster) was demonstrated by requirements for enzyme activity, selective inhibition with meso-tartrate and substrate specificity. 3. in each animal, the highest activity was found in kidney, followed by liver and brain, and no gender difference in t ... | 1992 | 1424565 |
| comparative study of sexual dimorphism of the innominate bone in rodents and amphibians. | sexual dimorphism in the shape of the innominate bone was demonstrated in the rat, mouse, chinese hamster (cricetulus griseus), frog (ranna nigromaculata), and newt (cynops pyrrhogaster) with a computer-assisted morphometric technique. in the rat, mouse, and hamster, ratios of ischium and pubis widths to the innominate bone length (inl) were larger in the males than in the females; however, the ratio of pubis length to inl was larger in the females than in the males. in the frog, the ratio of di ... | 1992 | 1443668 |
| homologous radioimmunoassay for bullfrog growth hormone. | antiserum against bullfrog growth hormone (fgh) was produced by immunizing rabbits with the highly purified fgh obtained from adenohypophyses of adult bullfrogs. histological studies on bullfrog adenohypophyses revealed that the cells that immunologically reacted with the antiserum against fgh corresponded to the ones positively stained with the antiserum against rat gh. the antiserum together with fgh and 125i-fgh was employed to develop a radioimmunoassay (ria) for fgh. several dilutions of pl ... | 1991 | 1874383 |
| amphibian prolactins: activity in the eft skin transepithelial potential bioassay. | the effects of purified prolactins isolated from frogs (fprl; rana catesbeiana) and newts (nprl; cynops pyrrhogaster) were compared with those of ovine prolactin (oprl) and thyrotropin releasing hormone (trh) in the eft (notophthalmus viridescens) skin transepithelial potential (tep) bioassay. at total doses as low as 0.4 micrograms/animal, both fprl and nprl were as effective as oprl in reducing eft skin tep. by contrast, trh at total doses as high as 400 micrograms/animal was ineffective in al ... | 1991 | 1908395 |
| purification and properties of newt prolactin. | a highly purified prolactin (prl) was obtained from pituitary glands of newts, cynops pyrrhogaster, by extraction of acetone-dried powder with acid acetone and high-performance liquid chromatography (hplc) on mono-q (anion exchange), superose-12 (gel filtration), and tsk-gel ods-120t (reverse-phase) columns with a yield of 4.5 mg per 325 mg of protein starting material. purification was monitored by sds-polyacrylamide gel electrophoresis (page) and western blotting analysis employing antiserum a ... | 1990 | 2295424 |
| how is the flagellar length of mature sperm determined? ii. comparison of tubulin synthesis in spermatids between newt and xenopus in vitro. | in order to elucidate mechanisms that control flagellar length of mature sperm, we studied in synchronous cell suspension cultures flagellar growth, tubulin pool, and tubulin synthesis in round spermatids of xenopus laevis and the newt cynops pyrrhogaster. the average final length of flagella in xenopus round spermatids was 35 mum, almost the same length as that in mature sperm, whereas in the newt round spermatids, the length was 210 mum, almost half that of mature sperm. kinetics of flagellar ... | 1990 | 2298244 |
| gastric leiomyomas in the japanese newt, cynops pyrrhogaster; ultrastructural observations. | nineteen of 700 outwardly healthy captive adult japanese newts, cynops pyrrhogaster, had nodular neoplasms protruding on the gastric serosal surface. these tumours were characterized as sharply circumscribed leiomyomas of the muscularis externa with occasional submucosal involvement. ultrastructural analysis of tumour myocytes revealed irregular-shaped, well-differentiated cells with cytoplasmic processes, and reduced quantities of intracellular myofibrils. they were surrounded by enlarged inter ... | 1990 | 2312798 |
| comparative studies on the vascular organization of carotid labyrinths of anurans and caudates. | the three-dimensional structures of the carotid labyrinth in five species of anurans representing four families (rana nigromaculata, rana catesbeiana, bufo japonicus, hyla arborea, and xenopus laevis), and three species of caudates representing three families (cynops pyrrhogaster, hynobius nebulosus, ambystoma mexicanum) were compared using vascular corrosion castings and scanning electron microscopy (sem). anuran carotid labyrinths are spherical in shape and are classified into two groups accor ... | 1990 | 2338718 |
| development and application of homologous radioimmunoassay for newt prolactin. | a specific and sensitive homologous radioimmunoassay (ria) for newt (cynops pyrrhogaster) prolactin (prl) was developed. prl isolated from newt pituitary glands was used for generating antiserum in a rabbit, for radioiodination, and for the standard. several dilutions of plasma and pituitary homogenate of newts yielded dose-response curves which were parallel to the standard curve. plasma from hypophysectomized newts showed the least amount of cross-reaction. pituitary homogenates of other speci ... | 1990 | 2354781 |
| cleavage plane determination in amphibian eggs. | in the present study using eggs of cynops pyrrhogaster and xenopus laevis, we examined (1) structural changes in the cytoplasm before the appearance of the cleavage furrow using a cytochemical method, (2) the time of cleavage plane determination depending on the mitotic apparatus (ma), by changing the shape of the eggs, and (3) the time of arrival of the "cleavage stimulus" at the cortex, by injecting colchicine solution or removing cytoplasm. results were as follows: (1) in amphibian eggs the d ... | 1990 | 2356982 |
| amphibian (urodele) myotomes display transitory anterior/posterior and medial/lateral differentiation patterns. | myotome differentiation during mexican axolotl (ambystoma mexicanum) somitogenesis was analyzed by employing anti-actin and anti-myosin monoclonal antibodies as molecular probes. myotome differentiation occurs after segmentation and proceeds in the cranial-to-caudal direction along the somite file. within individual somites myotome differentiation displays distinct polarities. examination of the somite file at the tailbud stage revealed that soon after segmentation, actin/myosin accumulate predo ... | 1989 | 2647546 |
| mauthner neurons survive metamorphosis in anurans: a comparative hrp study on the cytoarchitecture of mauthner neurons in amphibians. | giant medullary neurons were revealed in adult xenopus laevis and rana esculenta following hrp injections to the spinal cord. these neurons were identified as mauthner neurons because (1) they have the same position and orientation as the larval mauthner neurons, i.e., they lie at the level of the viiith nerve root. (2) they have two large dendritic trees that for each species are similar to those of the larval mauthner neurons, (3) they are clearly distinguishable from other large reticular neu ... | 1986 | 3081602 |
| how is the flagellar length of mature sperm determined? i. comparison of flagellar growth in spermatids between newt and xenopus in vitro. | the kinetics of flagellar growth in round spermatids were compared between xenopus laevis and cynops pyrrhogaster in vitro, the latter of which has about 13 times longer flagella in mature sperm than the former. in both species, more than 90% of the spermatids derived from marked primary spermatocytes grew flagella. in xenopus the average flagellar length increased to 28 microns by the 6th day and then stopped growth, while in the newt, flagellar growth did not stop until reaching 107 microns in ... | 1988 | 3371423 |
| total dna transcription in vitro: a procedure to detect highly repetitive and transcribable sequences with trna-like structures. | total dnas from various animals were transcribed in vitro in a hela cell extract, and it was found that one to several discrete rnas were transcribed by rna polymerase iii. with tortoise (geoclemys reevessi) and newt (cynops pyrrhogaster), distinct 6.5s and 8s rnas were transcribed from these respective dnas. representative phage clones carrying the 6.5s and 8s rna genes were isolated from genomic libraries of these animals, and the sequences of these genes were determined. the 5' parts of highl ... | 1986 | 3455763 |
| comparative studies on the electric nature of amphibian gonadotropin. | the isoelectric focusing (ief) profiles of pituitary gonadotropic (gth) activity in six species of adult male amphibians were examined in addition to the newt and bullfrog. the gth activity was measured by two radioreceptor assay (rra) systems; one with xenopus laevis testicular homogenate as the receptor preparation, and the other with anolis carolinensis testicular homogenate, both employing 125i-labeled rat fsh as the radioligand, or by a radioimmunoassay (ria) system for bullfrog basic gth ( ... | 1985 | 3874809 |
| monoamine oxidase in the neurohypophysis of the newt (cynops pyrrhogaster pyrrhogaster), the toad (bufo bufo japonicus) and the tortoise (clemmys japonica). | | 1972 | 4623962 |
| electrical coupling between fat cells in newt fat body and mouse brown fat. | white fat from the newt, triturus pyrrhogaster, fat body, and brown fat from the interscapular fat pad of newborn mice have been tested for the presence of low-resistance intercellular junctions. 42 pairs of amphibian fat cells and 15 pairs of mammalian brown fat cells were found to be "electrically coupled." in most of these cases intracellular deposition of a dye, niagara sky blue: 6b, was used to supplement and confirm direct observations of impalements. coupling was often difficult to find i ... | 1971 | 4938627 |
| experiments on a spontaneously orginated visceral tumor in the newt, triturus pyrrhogaster. | | 1970 | 5278142 |
| cultivation in vitro of the testis cord of the newt, triturus pyrrhogaster. | | 1969 | 5392793 |
| behaviour of histones and cytoplasmic basic proteins during embryogenesis of the japanese newt, triturus pyrrhogaster. | | 1969 | 5408616 |
| lymphosarcomatous disease of the newt, triturus pyrrhogaster. | | 1970 | 5538539 |
| follicle-stimulating hormone (fsh) receptors in the testis of the newt, cynops pyrrhogaster, and comparison of temperature dependency of the receptors with those of the other vertebrates. | | 1980 | 6245987 |
| [evaluation of amputation techniques for the study of limb regeneration in the newt and toad]. | a comparison between forelimb amputations through the radius-ulna and the humerus was made in the adult newt, cynops pyrrhogaster pyrrhogaster and the young toad, xenopus laevis. newts regenerated their forelimbs after the amputations and the new parts resembled the old in structure and function. toads regenerated their forelimbs incompletely after the amputations. the new parts lacked joints and fingers showing a simply elongate pattern. the effect of re-amputation of exposed bone on the regene ... | 1984 | 6468505 |
| comparative study of extracellular fibrils on the ectodermal layer in gastrulae of five amphibian species. | previous studies have shown the presence of a network of extracellular fibrils on the inner surface of the ectodermal layer of the ambystoma maculatum gastrulae. the alignment of the network along the blastopore-animal pole axis has suggested that the network of fibrils guides the migrating mesodermal cells in gastrulae by contact guidance. we have also shown that these fibrils can be deposited on substrata by explanted embryonic fragments and that substrata conditioned in this manner support di ... | 1983 | 6602807 |
| seasonal variation in pituitary gonadotropin in the adult male newt, cynops pyrrhogaster pyrrhogaster, revealed by isoelectric focusing technique and radioreceptor assay. | the seasonal variation in pituitary gonadotropin in the adult male newt, cynops pyrrhogaster pyrrhogaster was investigated by means of isoelectric focusing (ief) coupled with radioreceptor assay (rra), which employed anolis or xenopus testicular homogenates as receptors and 125i-rat fsh as radioligand. in the anolis rra system, the standard curve was obtained with 0.125-16 ng/tube of niamdd rat fsh i-3. purified preparations, chicken lh ief-1, chicken fsh agchd11113a and bullfrog basic gonadotro ... | 1981 | 6796397 |
| the degradation of urate in liver peroxisomes. association of allantoinase with allantoicase in amphibian liver but not in fish and invertebrate liver. | allantoinase and allantoicase were co-purified from frog (rana catesbeiana) liver. the ratio of the two enzyme activities remained constant during purification and was unchanged by a variety of treatments of the purified enzyme. these results suggest that allantoinase and allantoicase are located in the same protein. it was found that the two hepatic enzyme activities are also associated with the same protein in other frogs (xenopus laevis and rana nigromacultata), tadpoles (r. catesbeiana), and ... | 1983 | 6833275 |
| seasonal and geographical changes of spontaneous skin papillomas in the japanese newt cynops pyrrhogaster. | the occurrence of spontaneous skin papillomas in japanese newts (cynops pyrrhogaster) from niigata prefecture in northern japan was monitored over four seasons covering a period of 2 years. of 13,613 newts, 249 were found to possess papillomas. the percentage of newts with papillomas was highest in autumn, ranging from 1.93 to 5.45% of the total average. these values were more than four times as high as values obtained in the other three seasons (0.16 to 0.50%). a total of 12,167 newts were coll ... | 1982 | 7105040 |
| electron microscope study of vertebrate liver innervation. | liver fine structure was studied in various groups of vertebrates to reveal intrahepatic nerves. nerve fibers were found in the connective tissue of the liver in all mammals, birds, and reptiles studied (japanese monkey, crab-eating monkey, rabbit, guinea pig, rat, golden hamster, pigeon, japanese quail, and turtle, pseudemys scripta). nerve fibers also made direct contact with hepatocytes in these animals except for the rat and the golden hamster. intrahepatic nerves were rare or absent in amph ... | 1981 | 7316686 |
| development and application of a homologous radioimmunoassay for xenopus prolactin. | a specific and sensitive homologous radioimmunoassay (ria) for xenopus prolactin (xprl) was developed. prl isolated from x. laevis pituitary glands was used for generating antiserum in a rabbit, for radioligand and for the standard. pituitary homogenates and plasma from adult xenopus produced displacement curves parallel to the xprl standard. plasma from hypophysectomized xenopus showed negligible cross-reactivity. purified prls from other amphibian species such as the bullfrog (rana catesbeiana ... | 1995 | 7657154 |
| promotion of differentiation of newt primary spermatocytes into spermatids by mammalian fsh via sertoli cells. | our previous studies showed that mammalian follicle-stimulating hormone (fsh) promoted the differentiation of primary spermatocytes into elongated spermatids in organ culture of testes fragments from cynops pyrrhogaster. to elucidate the mechanism of fsh action, in this study the testes in the primary spermatocyte stage were dissociated and fractionated into germ and somatic cells, the latter comprising more than 80% sertoli cells. radioreceptor assays showed that fsh bound to somatic cells, ver ... | 1995 | 7673875 |
| sodefrin: a female-attracting peptide pheromone in newt cloacal glands. | a decapeptide called sodefrin was isolated from the abdominal gland of the cloaca of the male red-bellied newt, cynops pyrrhogaster. the native peptide, as well as the synthetic one, had a female-attracting activity. sodefrin was found in the apical portion of the epithelial cells of the abdominal gland. sodefrin is apparently species specific because it did not attract females of cynops ensicauda. this is the first amphibian pheromone to be identified and the first peptide pheromone identified ... | 1995 | 7886452 |
| hormonal control of response to and secretion of sex attractants in japanese newts. | hormonal control of sexual chemoattraction in the newt, cynops pyrrhogaster, was investigated by a water preference test. sexually inert newts injected with prolactin (prl) and human chorionic gonadotropin (hcg) in combination preferred the water in which newts of the opposite sex had been kept, whereas saline-injected specimens did not. this indicates that prl and hcg enhance the response of the newts to attractant(s) secreted by the opposite sex. the water in which prl plus hcg-treated newts h ... | 1994 | 8190778 |
| motion sickness in amphibians. | we explored the question of whether amphibians get motion sickness by exposing anurans (frogs) and urodeles (salamanders) to the provocative stimulus of parabolic aircraft flight. animals were fed before flight, and the presence of vomitus in their containers after flight was used to indicate motion-induced emesis. none of the species that we studied vomited during the 8 to 10 parabolas of each flight. however, at least one specimen from each of the anuran species rana rugosa, rana nigromaculata ... | 1993 | 8216158 |
| hormonal induction of male courtship behavior in the japanese newt, cynops pyrrhogaster. | in the breeding season, the sexually mature male newt, cynops pyrrhogaster, vibrates the tail in front of the female at an early stage of courtship. effects of prolactin (prl), gonadotropin (gth), and sex steroids on this behavior were investigated in the male paired with the female receiving prl and gth. the behavior was elicited in the sexually inert male by injections of prl of bovine, ovine, or bullfrog origin and human chorionic gonadotropin or bullfrog lh and fsh in combination. the effect ... | 1993 | 8294119 |
| comparison of mauthner cell size in sexually developed and undeveloped male red-bellied newts. | differences in mauthner (m) cell size were examined in sexually developed and undeveloped male red-bellied newts, cynops pyrrhogaster. the mean areas of nuclei and cell bodies of m cells and mean maximum and minimum diameters of the cell bodies in the sexually developed males were significantly larger than those in the sexually undeveloped ones. in the hypophysectomized male newts, all these parameters were not significantly different from those in the sexually undeveloped ones. these values wer ... | 1995 | 8586962 |
| [new sex pheromone isolated from the abdominal glands of male newt, cynops pyrrhogaster]. | sodefrin, a novel decapeptide which attracts female newts, cynops pyrrhogaster was isolated from the abdominal gland of the male of the same species. synthetic sodefrin was tested for its activity with sexually active females and males and sexually inert females. it attracted only sexually active females. the effect of sodefrin was blocked by a bilateral nostril plugging with cotton balls soaked in melted vaseline. immunoelectronmicroscopic study using antiserum against sodefrin revealed that so ... | 1995 | 8763038 |
| radioimmunoassay of a newt sex pheromone, sodefrin, and the influence of hormones on its level in the abdominal gland. | a specific and sensitive radioimmunoassay (ria) was developed for the measurement of sodefrin, a female-attracting decapeptide pheromone of the red-bellied newt, cynops pyrrhogaster. sodefrin synthesized according to the amino acid sequence of native sodefrin, isolated from the abdominal glands of the cloaca of the male newt, was used as a reference standard. an antiserum to sodefrin was produced by immunizing a rabbit with synthetic sodefrin that was extended on its c-terminus with cys coupled ... | 1996 | 8954769 |
| female-attracting pheromone in newt cloacal glands. | it has been postulated that male newts emit pheromones that attract females of the same species. female newts of the species cynops pyrrhogaster were attracted to water in which sexually active conspecific males had been kept, but not to water in which abdominal gland-ablated males had been kept, indicating that the attracting pheromone was secreted by or through the abdominal gland of the cloaca. an attempt has been made to isolate and characterize the female-attracting pheromone in the abdomin ... | 1997 | 9370206 |
| cloning of cdna for newt wt1 and the differential expression during spermatogenesis of the japanese newt, cynops pyrrhogaster. | to investigate the function of wilms' tumor 1 (wt1) during spermatogenesis, cdna for newt wt1 homolog was cloned and the expression of wt1 in newt testes was examined. the cdna is 2089 bp in length and encodes 426 amino acid (aa) residues. the deduced aa sequence shares 76 and 79% homology with human and xenopus wt1, respectively. northern blot analysis shows that wt1 mrna, 3.2 and 4.5 kb in length, are expressed in the testis and kidney. both wt1 mrna species are detected in various stages of s ... | 1998 | 9865970 |
| sodefrin: a novel sex pheromone in a newt. | the abdominal gland in the male red-bellied newt, cynops pyrrhogaster, is the source of a female-attracting pheromone. an attempt was made to isolate and characterize the female-attracting pheromone in the abdominal glands of male newts. the active substance, named sodefrin (from the japanese 'sodefuri' which means 'soliciting') has been isolated and shown to be a novel decapeptide with the sequence, ser-ile-pro-ser-lys-asp-ala-leu-leu-lys. its minimum effective concentration in water is 0.1-1.0 ... | 1999 | 10051096 |
| production of a recombinant newt growth hormone and its application for the development of a radioimmunoassay. | complementary dna (cdna) encoding newt (cynops pyrrhogaster) growth hormone (ngh) was cloned from a cdna library constructed from mrnas of newt pituitary glands and was expressed in escherichia coli. based on northern blot analysis using the cdna as a probe, the ngh mrna was estimated to be 940 bases in length. the recombinant ngh (nghr) had a molecular mass of 22 kda as determined by sds-page and possessed considerable bioactivity as determined in a xenopus cartilage assay. using the nghr, we p ... | 2000 | 10620427 |
| expression of helix-loop-helix type negative regulators of differentiation during limb regeneration in urodeles and anurans. | the urodele is capable of regenerating its limb by forming a blastema even in the adult. by contrast, the anuran, which is phylogenetically close to the urodele, loses this ability during metamorphosis and forms blastema-like tissues that develop only into a spike-like structure in the adult. in order to compare the molecular mechanism of the formation and maintenance of the blastema between the urodele and anuran, the genes encoding helix-loop-helix (hlh) type negative regulators of differentia ... | 1999 | 10646803 |
| hormonal control of urodele reproductive behavior. | hormonal control of expression of courtship behavior and of development of structures related to the reproductive behavior in two species of japanese newts, cynops pyrrhogaster and cynops ensicauda, was described. prolactin (prl) and androgen were essential factors for eliciting courtship behavior. in addition, arginine vasotocin markedly enhanced the expression of courtship behavior. prl induced migration to water, in which courtship and oviposition take place, and converted the integument from ... | 2000 | 10874169 |
| molecular cloning, functional characterization, and gene expression of a follicle-stimulating hormone receptor in the testis of newt cynops pyrrhogaster. | we previously demonstrated in vitro that mammalian follicle-stimulating hormone (fsh) stimulates the proliferation of newt secondary spermatogonia and their differentiation into primary spermatocytes. in the current study, we isolated a cdna from newt testis that encodes a fsh receptor (fsh-r). the total sequence homology in the deduced protein of the newt was approximately 70% with mammalian fsh-rs. mammalian cells, transiently transfected with the cloned newt fsh-r cdna, displayed specific bin ... | 2000 | 10944452 |
| newt prolactin and its involvement in reproduction. | the amino acid sequence of newt (cynops pyrrhogaster) prolactin deduced from the nucleotide sequence of its cdna showed a relatively high homology with sequences of chicken and sea turtle prolactins as well as with those of anuran prolactins. cynops prolactin receptor transcripts were detected in various tissues and organs, suggesting that prolactin plays multiple roles in urodeles. urodele prolactin was purified from the pituitaries of c. pyrrhogaster. antiserum against this prolactin was used ... | 2000 | 11149387 |
| an experimental animal model of split cord malformation. | in this study, we examined an experimental animal model of split cord malformation (scm) produced by the surgical induction of a fistula. in cynopus pyrrhogaster neurulae (stage 18.5 +/- 0.5), the neural plate was incised and divided to construct a fistula that mimicked a neurenteric canal. after the procedure, the development of these embryos was examined morphologically and histologically. following incubation, hemicords, hemicords with their own heminotochords, and dermal sinus were observed ... | 2000 | 11182638 |
| toxicity and toxin profiles of the newt, cynops pyrrhogaster from western japan. | a total of 382 specimens of a japanese newt, cynops pyrrhogaster, were collected from western japan during 1996 to 1999, and assayed for their individual, geographical, sexual, seasonal variations, and anatomical distribution of toxicity by mouse. most of the specimens tested showed toxicity scores ranging from 5 to 370 mu/g, where no seasonal, but large individual, sexual, and regional variations of toxicity were clearly recognized. among the parts, skin and muscle showed higher toxicity scores ... | 2001 | 11405279 |
| comparative study of sequential expression of the organizer-related genes in normal cynops pyrrhogaster embryos and mesodermalized ectoderm. | an artificially mesodermalized ectoderm (me) of early cynops pyrrhogaster gastrula acquires the organizer property; the me is able to induce the secondary axis. the expression of organizer-related genes was investigated during the mesodermalizing process of the me. the expression of c. pyrrhogaster organizer-related genes, such as bra, gsc, lim-1, chd and noggin, were analyzed. cynops pyrrhogaster shh expression was also investigated. the organizer-related genes were activated by 12 h after the ... | 2001 | 11473542 |
| astronewt: early development of newt in space. | astronewt experiment explores the effects of earth gravity on the early development of japanese red-bellied newt, cynops pyrrhogaster. since female newts keep spermatophore in cloaca, fertilized eggs could be obtained without mating. fertilization of newt's egg occurs just prior to spawning, so that gonadotrophic cues applied to females in orbit leads to laying eggs fertilized just in space. a property of newt being kept in hibernation at low temperature may be of great help for the space exp ... | 1996 | 11538624 |
| experimental split cord malformations. | to induce experimental split cord malformations (scms) produced through the surgical induction of a dorsal midline fistula. | 2002 | 12053040 |
| an ultrastructural and carotenoid analysis of the red ventrum of the japanese newt, cynops pyrrhogaster. | the ventral skin of the wild japanese newt cynops pyrrhogaster is creamy at metamorphosis, but turns red when mature. the color of the ventral skin of laboratory (lab)-reared newts stays yellow throughout their life. however, the mechanism for the red coloration of this animal still remains unknown. in this study, we have performed ultrastructural and carotenoid analyses of the red ventrum of wild and lab-reared japanese newts. using electron microscopy, we observed a number of xanthophores havi ... | 2002 | 12100492 |
| comparison of the morphology of the inner ear between newts and frogs in relation to their locomotory capability. | the ultrastructural differences between the inner ears of japanese red-bellied newts (cynops pyrrhogaster) and black-spotted pond frogs (rana nigromaculata) were investigated. scanning electron microscopic observations showed apparent morphological differences in the shape of the ampulla cristae and the localization of the striola in the saccular macula. there were differences in the length of the kinocilia of the sensory hairs in each sensory region. in addition, the diameters of the bundles of ... | 2002 | 12130811 |
| experimental analysis of gravitational effects on amphibian gastrulation. | the effects of simulated microgravity on blastopore (bp) formation were analysed in xenopus laevis and cynops pyrrhogaster embryos. simulated microgravity produced by clinostat rotation shifted the bp-forming region toward the vegetal pole, more markedly in cynops embryos than in xenopus embryos. the simulated microgravity induced aggregation of endoderm cells at the center of the embryo and separation between the endoderm and presumptive mesoderm (pm). these findings suggest that clinostat trea ... | 2002 | 12402923 |
| comparative peptidomics of the endocrine pancreas: islet hormones from the clawed frog xenopus laevis and the red-bellied newt cynops pyrrhogaster. | electrospray mass spectrometry coupled with reverse-phase hplc was used to identify peptides in the molecular mass range 3000-6000 da in extracts of the pancreata of the clawed frog xenopus laevis (anura: pipidae) and the red-bellied newt cynops pyrrhogaster (caudata: salamandridae). amino acid sequences of insulins, peptides derived from the post-translational processing of proglucagons and pancreatic polypeptide were determined by automated edman degradation. three molecular forms of insulin w ... | 2002 | 12475387 |
| matrix metalloproteinase-21, the human orthologue for xmmp, is expressed during fetal development and in cancer. | we have characterized a novel human matrix metalloproteinase (mmp-21) from human placenta dna complementary to rna (cdna). the 569 amino acid translation of the cdna includes all the typical features of an mmp family member, namely a signal sequence, a prodomain with a prcgvpd motif, a zinc-binding catalytic domain with an heighvlgl sequence, and a hemopexin-like domain flanked by two cysteine residues. furthermore, mmp-21 has a furin activation sequence, but no transmembrane sequence nor a cyto ... | 2002 | 12490321 |
| cpzpc, a newt zpc molecule, localizes to the inner surface of the egg envelope. | zona pellucida-3 is an essential molecule for the binding of sperm to the egg envelope and for induction of the acrosome reaction in mice. its homologous molecules, zpcs, have been widely identified in the eggs of many vertebrates, except for urodeles. in this study, to investigate the participation of zpc in newt fertilization, we cloned the cdna of newt zpc from the ovary of cynops pyrrhogaster by reverse transcription polymerase chain reaction (rt-pcr). the cdna was constructed from 1,397 nuc ... | 2003 | 12653251 |
| lectin histochemical study on the olfactory organ of the newt, cynops pyrrhogaster, revealed heterogeneous mucous environments in a single nasal cavity. | expression patterns of glycoconjugates were examined by lectin histochemistry in the nasal cavity of the japanese red-bellied newt, cynops pyrrhogaster. its nasal cavity consisted of two components, a flattened chamber, which was the main nasal chamber (mnc), and a lateral diverticulum called the lateral nasal sinus (lns), which communicated medially with the mnc. the mnc was lined with the olfactory epithelium (oe), while the diverticulum constituting the lns was lined with the vomeronasal epit ... | 2003 | 12698361 |
| food habit of the juvenile of the japanese newt cynops pyrrhogaster. | the previous study showed that the red coloration of the ventral skin of the japanese newt cynops pyrrhogaster was associated with the number of carotenoid vesicles and the content of carotenoid in the pigment cell of the skin. to elucidate the mechanism for the red coloration of the skin of the newt, we studied the food habit of the juvenile from the japanese newt cynops pyrrhogaster. sixty-two juveniles were collected in fukue island in nagasaki prefecture from november 2000 to may 2002 and di ... | 2003 | 12867714 |
| studies on amphibian yolk 1. the ultrastructure of the yolk platelet. | the yolk platelets of mature eggs and young embryonic cells of all amphibian species studied (rana pipiens, triturus pyrrhogaster, diemictylus viridescens, rana nigromaculata, and bufo vulgaris) have a superficial layer of fine particles or fibrils (ca. 50 a in diameter), a central main body with a crystalline lattice structure, and an enclosing membrane approximately 70 a in thickness. electron micrographs of the main body reveal hexagonal net (spacing ca. 70 a), square net (spacing ca. 80 a), ... | 1963 | 13962448 |
| a survey of blastocystis infection in anuran and urodele amphibians. | blastocystis infection in amphibians was surveyed in three species of anuran and one species of urodele amphibians captured at two distinct locations in japan. all three species of frogs were highly infected with blastocystis, while 69 individual urodele newts, cynopus pyrrhogaster, were negative for infection. eleven blastocystis isolates (47.8%) were recovered from 23 rana nigromaculata leopard frogs. twenty-three (92%) of 25 rana catesbeiana bullfrogs and all (100%) of 24 bufo japonicus japon ... | 2004 | 15177714 |
| hormonal control of meiosis initiation in the testis from japanese newt, cynops pyrrhogaster. | meiosis is an event that occurs prerequisitely and specifically in gametogenesis. however, the mechanisms of conversion from mitosis to meiosis are poorly understood. i will review the results so far obtained by us using newt testis as a model system, and discuss about the extrinsic mechanism(s) controlling the conversion from mitosis to meiosis. in the newt spermatogonia enter meiosis in the 8th generation after 7 mitotic divisions. we developed organ and reaggregate culture systems with a chem ... | 2004 | 15277712 |
| spatio-temporal expression of a daz-like gene in the japanese newt cynops pyrrhogaster that has no germ plasm. | to investigate the germ cell specification in urodeles, we cloned a daz-like sequence from the japanese newt cynops pyrrhogaster, cydazl, and raised antibodies specific to cydazl. cydazl is a homologue of the human daz (deleted in azoospermia), dazl, and xenopus dazl genes, which are involved in gametogenesis or germ cell specification. during gametogenesis, expression of cydazl mrna and cydazl protein was detected at first in the small previtellogenic oocytes in females but was not localized as ... | 2004 | 15490230 |
| daily and circadian variations of the pineal and ocular melatonin contents and their contributions to the circulating melatonin in the japanese newt, cynops pyrrhogaster. | daily and circadian variations of melatonin contents in the diencephalic region containing the pineal organ, the lateral eyes, and plasma were studied in a urodele amphibian, the japanese newt (cynops pyrrhogaster), to investigate the possible roles of melatonin in the circadian system. melatonin levels in the pineal region and the lateral eyes exhibited daily variations with higher levels during the dark phase than during the light phase under a light-dark cycle of 12 h light and 12 h darkness ... | 2005 | 15684585 |
| generation of transgenic newt cynops pyrrhogaster for regeneration study. | to take advantage of the ample potential for tissue regeneration by the newt, a technique to create transgenic newt was developed. the technique was based on a procedure for producing transgenic xenopus, but modified to adapt to the different sperm morphology and to overcome the refractoriness of newt eggs to activation by normal cleavage. sperm was collected from mature testes early in winter, permeabilized with digitonin, but without treatment of egg extract. efficient egg activation was achie ... | 2005 | 15712266 |
| prolactin acts centrally to enhance newt courtship behavior. | the effects of intracerebroventricular (icv) and intraperitoneal (ip) injections of ovine prolactin (prl), antiserum against newt prl, and antibody against the newt prl receptor on the expression of courtship behavior of male newts, cynops pyrrhogaster, were studied to see whether prl acts centrally or peripherally to induce the behavior. injections of prl by either route into gonadotropin-primed males enhanced the expression of the behavior dose-dependently. the minimum effective amount of ovin ... | 2005 | 15748718 |
| amphibian pheromones and endocrine control of their secretion. | amphibian sex pheromones of 3 urodele (cynops pyrrhogaster, c. ensicauda, and plethodon jordani) and 1 anuran (litoria splendida) species have been isolated and characterized and found to be either small peptides or larger proteins. each pheromone secreted by the male acts on conspecific females. endocrine control of pheromone secretion has been best studied in cynops. the c. pyrrhogaster pheromone, sodefrin, and the c. ensicauda pheromone, silefrin, are generated from their precursor proteins. ... | 2005 | 15891015 |
| differential expression of neurofilament 200-like immunoreactivity in the main olfactory and vomeronasal systems of the japanese newt, cynops pyrrhogaster. | expression of neurofilament 200 (nf200)-like immunoreactivity was examined in the main olfactory system and the vomeronasal system of the japanese newt, cynops pyrrhogaster, using anti-porcine nf200 monoclonal antibody (clone n52) to investigate the differences in phenotypical characteristics between these systems. the entire nasal cavity was a flattened single chamber consisting of the main nasal chamber (mnc) and the lateral nasal sinus (lns) communicating with each other. the olfactory epithe ... | 2005 | 16082118 |
| the outermost layer of egg-jelly is crucial to successful fertilization in the newt, cynops pyrrhogaster. | the significance of egg-jelly layers in internal fertilization was evaluated in the newt, cynops pyrrhogaster. in this species, six egg-jelly layers, j1, j2, j3, j4, j5 and the outermost j6 layers, are accumulated on the surface of the fertilizable eggs in pars convoluta of the oviduct. when a large number of sperm (about 6 x 10(5)) were placed on eggs having different numbers of jelly layers, all the eggs were fully fertilized, although many of the eggs developed abnormally. upon insemination u ... | 2006 | 17068800 |
| isolation, characterization and bioactivity of a region-specific pheromone, [val8]sodefrin from the newt cynops pyrrhogaster. | previous analysis of pcr products derived from total rna from the abdominal gland of the male newt, cynops pyrrhogaster, inhabiting the nara area of japan led to the identification of a gene encoding [val(8)]sodefrin, as well as the female-attracting peptide pheromone, sodefrin. in this study, purification of this sodefrin variant from the abdominal glands of male newts from the nara area was accomplished using gel-filtration chromatography and reversed-phase hplc. amino acid sequence analysis a ... | 2007 | 17275139 |
| characterization of a sperm factor for egg activation at fertilization of the newt cynops pyrrhogaster. | eggs of the newt, cynops pyrrhogaster, arrested at the second meiotic metaphase are activated by sperm at fertilization and then complete meiosis to initiate development. we highly purified a sperm factor for egg activation from a sperm extract with several chromatographies. the purified fraction containing only a 45 kda protein induced egg activation accompanied by an intracellular ca2+ increase when injected into unfertilized eggs. although injection of mouse phospholipase c (plc) zeta-mrna ca ... | 2007 | 17499700 |
| evidence for processing enzymes in the abdominal gland of the newt, cynops pyrrhogaster, that generate sodefrin from its biosynthetic precursor. | sodefrin (ser-ile-pro-ser-lys-asp-ala-leu-leu-lys) is a female-attracting peptide pheromone secreted by the abdominal gland of the male red-bellied newt, cynops pyrrhogaster. sequence analysis of a cdna encoding sodefrin revealed that the peptide is located in the c-terminal region of its precursor protein (residues 177-186 of preprosodefrin) and extended from its c-terminus by the tripeptide sequence ile(187)-ser(188)-ala(189) and flanked at its n-terminus by leu(174)-gly(175)-arg(176). this su ... | 2007 | 17867852 |
| comparison of molecular and cellular events during lower jaw regeneration of newt (cynops pyrrhogaster) and west african clawed frog (xenopus tropicalis). | when mammals, including humans, lose a major part of their lower jaw, they are unable to regenerate the lost structures. urodele amphibians, especially newts, can regenerate their lower jaw after amputation, whereas most anuran amphibians, including the west african clawed frog, can not. in the present study, we investigated the difference between newts and frogs during lower jaw regeneration. one difference was the distribution of myosin heavy chain (mhc) mrna after lower jaw amputation: mhc mr ... | 2008 | 18161063 |
| phylogenic aspects of the amphibian dual olfactory system. | the phylogenic significance of the subdivision of dual olfactory system is reviewed mainly on the basis of our findings by electron microscopy and lectin histochemistry in the three amphibian species. the dual olfactory system is present in common in these species and consists of the projection from the olfactory epithelium (oe) to the main olfactory bulb (mob) and that from the vomeronasal epithelium (vne) to the accessory olfactory bulb (aob). the phylogenic significance of subdivisions in the ... | 2008 | 18250565 |
| a novel non-lens betagamma-crystallin and trefoil factor complex from amphibian skin and its functional implications. | in vertebrates, non-lens betagamma-crystallins are widely expressed in various tissues, but their functions are unknown. the molecular mechanisms of trefoil factors, initiators of mucosal healing and being greatly involved in tumorigenesis, have remained elusive. | 2008 | 18335045 |
| endocrine regulation of reproductive behavior in the newt cynops pyrrhogaster. | hormonal control of the expression of courtship behavior and of secretion of the female-attracting pheromone sodefrin by the male red-bellied newt, cynops pyrrhogaster, together with the hormonal influence on the responsiveness to the pheromone in the female, is reviewed.expression of the initial stage of the courtship behavior, i.e., tail vibration by the male in front of the female, is dependent on prolactin (prl) and androgen. during the courtship, sodefrin seems to be released from the cloac ... | 2000 | 18517290 |
| promotion of spermatogonial proliferation by neuregulin 1 in newt (cynops pyrrhogaster) testis. | we have previously shown that mammalian follicle-stimulating hormone (fsh) promotes the proliferation of spermatogonia and their differentiation into primary spermatocytes in organ culture of newt testis. in the current study, we performed microarray analysis to isolate local factors secreted from somatic cells upon fsh treatment and acting on the germ cells. we identified neuregulin 1 (nrg1) as a novel fsh-upregulated clone homologous to mouse nrg1 known to control cell proliferation, different ... | 2008 | 18586089 |
| hormone-mediated reproductive behavior in the red-bellied newt. | hormonal involvement in the performance of reproductive behavior of the red-bellied newt cynops pyrrhogaster is described. the sexually developed male newt is likely to recognize the sexually responsive female newt by a yet unidentified substance released from the oviduct, secretion of this substance being stimulated by prolactin (prl) and estrogen. at the initial stage of courtship behavior, the male newt vibrates his tail vigorously in front of the female partner. this action is elicited by pr ... | 2009 | 19456338 |
| identification of the sperm motility-initiating substance in the newt, cynops pyrrhogaster, and its possible relationship with the acrosome reaction during internal fertilization. | motility initiation is a key event during internal fertilization of female-stored sperm, although the underlying mechanisms remain unclear. in internally fertilizing urodeles, quiescent sperm initiate motility on the surface of the egg-jelly, a thick extracellular matrix that accumulates around the egg in oviduct. by immunizing mice with egg-jelly extracts, we successfully generated an alpha34 monoclonal antibody (mab) which neutralized sperm motility-initiating activity in the egg-jelly of the ... | 2010 | 20209432 |
| prolactin increases the synthesis of 7alpha-hydroxypregnenolone, a key factor for induction of locomotor activity, in breeding male newts. | we recently found that the japanese red-bellied newt, cynops pyrrhogaster, actively produces 7alpha-hydroxypregnenolone, a previously undescribed amphibian neurosteroid. 7alpha-hydroxypregnenolone stimulates locomotor activity of male newts. locomotor activity of male newts increases during the breeding period as in other wild animals, but the molecular mechanism for such a change in locomotor activity is poorly understood. here we show that the adenohypophyseal hormone prolactin (prl) stimulate ... | 2010 | 20219980 |
| distribution of 7b2 (secretogranin v)-like immunoreactivity in the japanese red-bellied newt (cynops pyrrhogaster) pituitary. | in this study, we examined 7b2 (secretogranin v)-like immunoreactivity (ir) in the japanese red-bellied newt (cynops pyrrhogaster) pituitary. results showed that the pars nervosa was filled with immunoreactive granules. in the pars intermedia, all melanotrophs showed 7b2-ir. in the pars distalis, immunoreactive cells were dispersed, and the 7b2-immunoreactive cells were also immunopositive for the beta-subunit of bullfrog luteinizing hormone (flhbeta). 7b2-ir co-localized with flhbeta-ir in the ... | 2010 | 20434189 |
| the ca2+ increase by the sperm factor in physiologically polyspermic newt fertilization: its signaling mechanism in egg cytoplasm and the species-specificity. | the newt, cynops pyrrhogaster, exhibits physiological polyspermic fertilization, in which several sperm enter an egg before egg activation. an intracellular ca(2+) increase occurs as a ca(2+) wave at each sperm entry site in the polyspermic egg. some ca(2+) waves are preceded by a transient spike-like ca(2+) increase, probably caused by a tryptic protease in the sperm acrosome at the contact of sperm on the egg surface. the following ca(2+) wave was induced by a sperm factor derived from sperm c ... | 2011 | 21237143 |
| comparative morphology of the osteocyte lacunocanalicular system in various vertebrates. | osteocytes are embedded in the bone matrix, and they communicate with adjacent osteocytes, osteoblasts, and osteoclasts through the osteocyte lacunocanalicular system. osteocytes are believed to be essential for the maintenance of bone homeostasis because they regulate mechanical sensing and mineral metabolism in mammalian bones; however, osteocyte morphology in other vertebrates has not been well documented. we conducted a comparative study on the morphology of osteocytes and the lacunocanalicu ... | 2011 | 21499992 |
| Phase-II conjugation ability for PAH metabolism in amphibians: Characteristics and inter-species differences. | The present study examines amphibian metabolic activity - particularly conjugation - by analysis of pyrene (a four ring, polycyclic aromatic hydrocarbon) metabolites using high-performance liquid chromatography (HPLC) with fluorescence detector (FD), a mass spectrometry detector (MS) system and kinetic analysis of conjugation enzymes. Six amphibian species were exposed to pyrene (dissolved in water): African claw frog (Xenopus laevis); Tago's brown frog (Rana tagoi); Montane brown frog (Rana orn ... | 2011 | 21819814 |
| effects of changes in sodium electrochemical potential gradient on p-aminohippurate transport in newt kidney. | 1. the relation between p-aminohippurate uptake and the electrochemical potential gradient of na+ (delta muna+) across the peritubular membrane was examined in newt (triturus pyrrhogaster) kidney. the delta muna+ was modified by changing cellular na+ concentration and/or lowering the electrical potential difference across the peritubular membrane (peritubular membrane potential) 2. elevation of external k+ concentration or addition of alanine at 40 mm to the medium decreased the delta muna+ main ... | 2004 | 534632 |
| transient outward currents and changes of their gating properties after cell activation in thrombocytes of the newt. | 1. the electrical properties of the cell membrane of thrombocytes in the newt, triturus pyrrhogaster, were studied using the whole-cell variation of the patch-electrode voltage-clamp technique. 2. in medium containing ca2+ (1.8 mm), activated thrombocytes became round and then spread on the glass. activation of thrombocytes was inhibited by the removal of external ca2+ and addition of 1 w/v% albumin to the external media. 3. for thrombocytes kept in the resting state, depolarizations more positi ... | 2008 | 2443665 |
| new translation system of mrna coding for neurotransmitter receptors using oocytes of the newt, cynops pyrrhogaster. | eel electroplax mrna was injected into oocytes of newts (cynops pyrrhogaster) and the injection induced synthesis of a nicotinic acetylcholine receptor in the oocyte membrane. the time course of the induction and dose-response relationship of the receptor were recorded electrophysiologically. the receptor responses and their developmental changes were similar to those of xenopus oocytes injected with eel mrna. newt oocytes lived much longer (7-10 days) than xenopus oocytes (3-4 days) under our e ... | 2013 | 3742236 |
| the origin of the luteinizing hormone-releasing hormone (lhrh) neurons in newts (cynops pyrrhogaster): the effect of olfactory placode ablation. | neurons containing luteinizing hormone-releasing hormone (lhrh) are first detected in newt embryos (cynops pyrrhogaster) in the olfactory epithelium and ventromedial portion of the olfactory nerve, after which they sequentially appear in the intracerebral course of the terminal nerve at prometamorphosis, and in the septo-preoptic area at postmetamorphosis. in adults, however, lhrh-immunoreactive cells are rarely seen in the nasal region, and their distribution shifts into the brain, suggesting t ... | 1965 | 1423481 |
| an electrically mediated block to polyspermy in the primitive urodele hynobius nebulosus and phylogenetic comparison with other amphibians. | at fertilization, the egg of the primitive urodele, hynobius nebulosus, produced a fertilization potential which rose from -12 to +47 mv. a similar activation potential was elicited by pricking with a needle, by applying a23187, or by electric shock. the potential change was mediated by an increased permeability to cl-. clamping the egg's membrane potential at +40 mv blocked fertilization, while clamping at +20 mv induced polyspermy. these results indicated the occurrence of an electrical polysp ... | 2009 | 2744241 |
| evidence that the voltage-dependent component in the fertilization process is contributed by the sperm. | to investigate the mechanisms that account for the voltage dependence of fertilization and provide an electrical block to polyspermy, we studied cross-fertilizations between three species of amphibians having different degrees of voltage dependence. anurans, such as the toad bufo japonicus, as well as the primitive urodele hynobius nebulosus, have voltage-dependent fertilization; other urodeles, such as cynops pyrrhogaster, have voltage-independent fertilization (y. iwao, 1989, dev. biol. 134, 4 ... | 2009 | 2744242 |
| cell surface changes during cleavage of newt eggs: scanning electron microscopic studies. | scanning electron microscopic studies were carried out on changes of the cell surface during the first cleavage of eggs of the newt, cynopus (triturus) pyrrhogaster. a dense population of elongated microvilli, which initially covered a double line indicating the initial furrow and stress marks running on each side of it, became located inside the pigmented area a little apart from its border with the unpigmented area when this borderline was established. this finding, together with data of carbo ... | 2014 | 4039355 |
| electron-microscopic observations on the finer structure of basophilic granulocytes of newt (triturus pyrrhogaster). | | 2016 | 4960340 |
| locomotion pattern and trunk musculoskeletal architecture among urodela. | we comparatively examined the trunk musculature and prezygapophyseal angle of mid-trunk vertebra in eight urodele species with different locomotive modes (aquatic siren intermedia, amphiuma tridactylum, necturus maculosus and andrias japonicus; semi-aquatic cynops pyrrhogaster, cynops ensicauda; and terrestrial hynobius nigrescens, hynobius lichenatus and ambystoma tigrinum). we found that the more terrestrial species were characterized by larger dorsal and abdominal muscle weight ratios compare ... | 2015 | 25914411 |
| functional and morphological variety in trunk muscles of urodela. | trunk musculature in urodela species varies by habitat. in this study, trunk musculature was examined in five species of adult salamanders representing three different habitats: aquatic species, amphiuma tridactylum and necturus maculosus; semi-aquatic species, cynops pyrrhogaster; terrestrial species, hynobius nigrescens and ambystoma tigrinum. more terrestrial species have heavier dorsal and ventral trunk muscles than more aquatic forms. by contrast, the lateral hypaxial musculature was strong ... | 2014 | 24065082 |
| learning about non-predators and safe places: the forgotten elements of risk assessment. | a fundamental prerequisite for prey to avoid being captured is the ability to distinguish dangerous stimuli such as predators and risky habitats from non-dangerous stimuli such as non-predators and safe locations. most research to date has focused on mechanisms allowing prey to learn to recognize risky stimuli. the paradox of learned predator recognition is that its remarkable efficiency leaves room for potentially costly mistakes if prey inadvertently learn to recognize non-predatory species as ... | 2011 | 21203793 |
| amphibians have immunoglobulins similar to ancestral igd and iga from amniotes. | we studied the immunoglobulin genes from either the genomes or rnas of amphibians. in particular, we obtained data from one frog genome (nanorana parkeri) and three transcriptomes of the caudata order (andrias davidianus, notophthalmus viridescens and cynops pyrrhogaster). apart from the immunoglobulins igm and igy previously described, we identified several igd related immunoglobulins. the species n. parkeri, n. viridescens and c. pyrrhogaster have two igd genes, while andrias davidianus has th ... | 2016 | 26675067 |