bluuebunny/crossref_metadata_2025_split huggingface dataset:
Eversible abdominal vesicles and some observations of the male reproductive system of the spoon wing lacewing Palmipenna (Neuroptera: Nemopteridae)
Authors: Walker M. H. , Picker M. D. , Leon B. 
Published: February 2005

AbstractThe anatomy and histology of the abdominal eversible vesicles and the male reproductive tract of the spoonwing lacewing Palmipenna (Neuroptera: Nemopteridae) have been examined. The eversible vesicles open as a pair of large bulbous sacs between tergites five and six, each folding into halves during retraction. They consist of highly pleated cuticle, beneath which are typical gland cells, each having a circular or oval end apparatus surrounded by closely packed microvilli. These communicate to the surface via cuticularized channels. In spite of considerable behavioral observations, male Palmipenna were never noted with everted vesicles. Even during mating trials, where females were presented to males in the field, the vesicles were never everted during the attempted copulation that ensued. Our observations indicate that mate attraction is mediated by the release of a female pheromone. The function of the eversible vesicles and their associated gland cells remains unknown, and their structure appears to be unique to the Nemopteridae. The reproductive tract is similar to that of other Neuroptera, consisting of a pair of five‐lobed testes, a medium‐to‐large pair of seminal vesicles, and three pairs of accessory glands. The major accessory glands are surrounded by circular and longitudinal muscle, and are lined by an epithelium, the cells of which presumably secrete the amorphous rods of material always present in this pair of glands. The sperm in the seminal vesicles are elongate, with a pointed head and a 9 + 9 + 2 configuration in the flagellum. A single spermatophore, similar in shape to that described for other Neuroptera, was found occluding the bursa copulatrix of a teneral female. © 1994 Wiley‐Liss, Inc.
Furrowing surface contraction wave coincident with primary neural induction in amphibian embryos
Authors: Brodland G. Wayne , Gordon Richard , Scott Michael J. , Björklund Natalie K. , Luchka Kurt B. , Martin C. Cristofre , Matuga Cindy , Globus Morton , Vethamany‐Globus Swani , Shu Dongwei 
Published: February 2005

AbstractWe predicted, and have now observed, a surface contraction wave in axolotl (Ambystoma mexicanum) embryos that appears to coincide temporally and spatially with primary neural induction and homoiogenetic induction, and with involution of the chordomesoderm. The wave starts from a focus anterior to the dorsal lip of the blastopore and spreads as an ellipse, until part of it encounters the rim of the blastopore and vanishes there. The remaining are then continues over the dorsal hemisphere until it reforms an ellipse that decreases in size. About 9 to 12 hours after it begins, the wave vanishes at a focus diametrically opposite its point of origin. The wave involves both local contraction and furrowing in the monolayer ectoderm. To a good approximation, the hemispherical portion of the ectoderm traversed by the wave becomes neuroepithelium, while the ectoderm not transversed by the wave becomes epidermis. The wave might provide a mechanism to determine the time and location at which neuroepithelial differentiation occurs. © 1994 Wiley‐Liss, Inc.
Fine structures on the surface of nuptial pads of male hylid and rhacophorid frogs
Authors: Kurabuchi Shingo 
Published: February 2005

AbstractNuptial pads, secondary sexual characteristics of male frogs, develop on the first digit of the hand of Hyla japonica in the family Hylidae and of Rhacophorus schlegelii in the family Rhacophoridae, and on both the first and second digits of the rhacophorids Buergeria buergeri and B. japonica. By scanning electron microscopy (SEM), it was seen that numerous mounds covered the surface of the pads. Mounds were similarly hemispherical in R. schlegelii and B. buergeri and flat in B. japonica. The mounds of H. japonica were irregular in shape and size and some of them stood in rows. Fine columnar protuberances were present all over the surfaces of the mounds in this species. Numerous peg‐like protuberances projected radially upward from the top of the mounds in B. buergeri and B. japonica. Irregular‐shaped, leaf‐like protuberances bearing knobby or rod‐shaped apical protrusions were present on the top of the mounds in R. schlegelii. In pads observed by transmission electron microscopy, the outermost epithelial monolayer of the mounds was generally thick, especially at the top, compared to that of the rest of the skin. Epidermal cells in this layer were well keratinized, devoid of organelles, and contained closely packed, fine filaments within a dense matrix. Apical accessory protuberances projecting from the outermost cells were also packed with dense filamentous materials, showing rigid comb‐like structures. © 1994 Wiley‐Liss, Inc.
Composite, haustellate mouthparts in netwinged beetle and firefly larvae (Coleoptera, Cantharoidea: Lycidae, Lampyridae)
Authors: Cicero Joseph M. 
Published: February 2005

AbstractDuring lycid embryogenesis, labral and mandibular anlagen develop separately. Each anterolateral corner of the labrum elongates into a stylet, while the whole of each mandible involutes into a flute that is open to the lateral aspects. The stylets and flutes interlock in such a way as to leave canals, fashioning left and right haustellate apparatuses. During lampyrid embryogenesis, only one pair of anlagen forms instead of two. The pair matures into sharp, arcuate appendages that appear to be typical mandibles, but nevertheless a canal forms internally. The canal is not formed by coadaptation of two appendages; instead, cells within the pair create the canal autonomously. Indications are that the canal is homologous between these two families. It is suggested that in lampyrids, labral and mandibular cell fields develop together in the same anlage but behave according to their own respective programs, forming the canal with morphogenetic movements that are comparable to those of lycids. © 1994 Wiley‐Liss, Inc.
Antennal sensilla of Rhodnius
Authors: Catalá Silvia , Schofield Christopher 
Published: February 2005

AbstractBy scanning electron microscopy, sensilla type and distribution were studied on the antennae of ten species of Rhodnius. No sexual dimorphism was apparent. Intraspecific differences in sensillar pattern were shown to be potentially useful in species determination and to agree with results from biochemical studies and previous morphometric studies in terms of species affinities. © 1994 Wiley‐Liss, Inc.
Mechanism of internal fertilization in Pegea socia (Tunicata, Thaliacea), a salp with a solid oviduct
Authors: Holland L. Z. , Miller R. L. 
Published: February 2005

AbstractThe ovary of the salp Pegea socia (Bosc, 1802) is located at the end of an atrial diverticulum. The ovary consists of a single oocyte encased in a layer of follicle cells and is connected to the atrial epithelium by an oviduct. Transmission electron microscopy shows that the oocyte lacks a vitelline layer, cortical granules, and yolk granules and that the oviduct lacks a continuous lumen. What previous authors thought was a lumen is a line of dense intercellular junctions running down the center of the oviduct. The sperm nucleus in this species, as in other salps, is elongate. The tubular mitochondrion spirals about the sperm nucleus giving it a corkscrew‐shape appearance. Sperm reach the ovary when the oocyte is still at the germinal vesicle stage. Many sperm swim up the atrial diverticulum and burrow through the cells of the atrial epithelium, oviduct, and follicular epithelium. Thus oviduct shortening, which occurs when the oocyte is in the meiotic divisions, is evidently unrelated to sperm moving up the oviduct. All previous authors, who argued either that a continuous lumen is necessary for sperm to move up the oviduct or that sperm bypass the oviduct, were incorrect. © 1994 Wiley‐Liss, Inc.
Effects of the anabolic steroid nandrolone phenylpropionate on craniofacial growth in rats
Authors: Noda Kazunobu , Chang Hong‐Po , Takahashi Ichiro , Kinoshita Zennosuke , Kawamoto Tatsuo 
Published: February 2005

AbstractPrimary testosterone and its derivatives are anabolic steroids used in the treatment of osteoporosis and Turner syndrome. They also enhance fast‐twitch muscle weight in female rats. The present study examines the effect of an anabolic steroid on craniofacial growth and development in rats. Five‐week‐old female Sprague‐Dawley rats (125) were divided into experimental and control groups. The experimental group was injected subcutaneously with 1 mg nandrolone phenylpropionate in the interscapular region on alternate days, whereas those in the control group were injected with a vehicle, arachis oil. Rats were sacrificed at 60 and 120 days of age. Cephalometric analysis of soft X‐ray cephalograms showed that chronic administration of the anabolic steroid, nandrolone phenylpropionate, resulted in: (1) about a 20% increase in body weight, (2) an increase in total skull length, (3) elongation of the maxillary and mandibular incisors, (4) an increase in the depth of the antegonial notch, and (5) downward‐forward growth of the viscerocranium against the neurocranium. These results suggest that nandrolone phenylpropionate may accelerate craniofacial growth and/or induce high functional activity of the masticatory muscles in female rats. © 1994 Wiley‐Liss, Inc.
Cochlear and lagenar ganglia of the chicken
Authors: Fischer Franz Peter , Eisensamer Brigitte , Manley Geoffrey A. 
Published: February 2005

AbstractCochlear and lagenar components of the statoacoustical ganglion in the inner ear of one chicken were studied quantitatively in the TEM. Both myelinated and unmyelinated nerve fibers were present in these two parts of the ganglion and in a putative efferent bundle within the ganglion. The cochlear portion had the lowest, the efferent bundle the highest percentage of unmyelinated fibers. Compared to the other parts of the ganglia, the cochlear fibers had a high degree of homogeneity, especially in fiber size. Some gradients in the baso‐apical direction were found, such as an increase in the size of myelinated cochlear fibers from the base to the apex. Based on the ultrastructure of cellular components, no distinct populations of cell bodies within the statoacoustical ganglion were definable.The ganglion contained some 8,000 cochlear and about 1,200–2,000 lagenar neurons. The putative efferent bundle had only 150–200 fibers. This cannot be the total number of efferents to the hair cells in both the basilar papilla and the lagena. A large number of efferent fibers to the auditory papillae presumably run mingled among the afferent fibers. © 1994 Wiley‐Liss, Inc.
Pigment pattern formation in larval ambystomatid salamanders: Ambystoma talpoideum, Ambystoma barbouri, and Ambystoma annulatum
Authors: Olsson Lennart 
Published: February 2005

AbstractThe pigment pattern formation in embryos and larvae of three ambystomatid salamanders was investigated in an evolutionary context. Early neural crest development was studied with scanning electron microscopy. Pigment cell migration and pattern formation were investigated at the light microscopy level with markers that labelled the two pigment cell types specifically before they were fully differentiated. In all three species, the pigment pattern formation started when xanthophores that had first formed aggregates in the crest migrated ventrally. As previously observed in other species, vertical bars always form by a mechanism involving earlier onset of migration in melanophores than in xanthophores and aggregate formation in the crest. In Ambystoma talpoideum and A. annulatum, a pattern of vertical chromatophore bars formed, which was superimposed on a pattern of horizontal stripes. In Ambystoma barbouri, the tendency to form this pattern was obscured by the high density of melanophores. It is suggested that variation among species may be due to differences in the chromatophore density and in the melanophore/xanthophore ratio. Mapping of the evolution of vertical bars onto existing phylogenies for the group was confounded by controversies about how to interpret the phylogenetic data. On the phylogeny that takes all the available evidence into account, there are two equally parsimonious mappings. Vertical bars have either evolved only once and been lost twice, or evolved twice and been lost once. This rather conservative pattern can be explained both as an effect of stabilizing selection and as a result of developmental constraints. © 1994 Wiley‐Liss, Inc.
Harderian gland ultrastructure of the black sea bottlenose dolphin (Tursiops truncatus ponticus)
Authors: Bodyak Natalie D. , Stepanova Lily V. 
Published: February 2005

AbstractExamination of the Harderian gland structure of the Black Sea bottlenose dolphin, Tursiops truncatus ponticus, at macroscopic, microscopic, and electron microscopic levels shows significant sexual dimorphism. The epithelial cells of male and female glands are different cell types, capable of producing chemically different products. Secretory cells in both sexes contain secretion granules that produce a secretion consisting mainly of proteins and carbohydrates, but thought to be sex‐specific in composition. The female glands also contain lipid secretion granules. It is suggested that in the bottlenose dolphin the Harderian gland functions to produce sexually distinct pheromones and may have other physiological activities, e.g., participating in local immunological or endocrine‐related reactions. © 1994 Wiley‐Liss, Inc.
Migration of intravascular trophoblast cells in uterine arteries of the golden hamster: A scanning electron microscopic study
Authors: Fuller Eugene G. , Highison Gregory J. , Tibbitts F. Donald , Fuller Bradley D. 
Published: February 2005

AbstractIntravascular trophoblast (IVT) cells, derived from the trophoblast of the developing hamster embryo, are known to migrate in retrograde fashion into the uterine arteries. There they migrate to a certain point, destroy and replace the endothelial lining, and modify the smooth muscle of the arteries. The dilated vessels that result presumably enhance the flow of blood to the placental exchange area. The morphology of IVT cells in the hamster placenta was investigated by scanning and transmission electron microscopy. Although occasional single migrating cells were observed, the IVT generally appear as sheets of large, contiguous, sometimes overlapping cells that spread over the endothelial surfaces of the uterine central terminal arteries and vascular knot arteries. This process seems to be aided by the appearance of filopodia, which make contact either with other intravascular trophoblast cells or the endothelium. After consolidation, the IVT cells act as a functional part of the vessel lining and are readily distinguished from the surrounding endothelium by their numerous microvilli. The final distribution of the IVT cells is patchy rather than uniform. © 1994 Wiley‐Liss, Inc.
Basilar papilla of the canary and zebra finch: A quantitative scanning electron microscopical description
Authors: Gleich Otto , Manley Geoffrey A. , Mandl Alexandra , Dooling Robert J. 
Published: February 2005

AbstractMorphological parameters of the apical surface of canary and zebra finch basilar papillae were quantitatively evaluated by scanning electron microscopy. The papillar length is ∼ 1.6 mm in both species. The zebra‐finch papilla has a larger number of hair cells and is wider in the apical half of the papilla as compared to the canary. These two small songbird species have the smallest number of hair cells and the smallest papillae of the bird species investigated to date. The orientation of the hair cells is much more homogenous as compared to other species. Also, the discrepancy in the number of stereovilli of neural and abneural hair cells is much larger than in other bird species. A detailed analysis of gradients across the papilla in the canary revealed that anatomical parameters change in the neural half, whereas they remain rather constant in the abneural half of the papilla. There were, however, no obvious borders that separated distinct hair cell populations in either species. © 1994 Wiley‐Liss, Inc.
Ultrastructure of the tubular accessory gland in Haemaphysalis longicornis (Acari: Ixodidae)
Authors: Kakuda Hiroyuki , Koga Takashi , Mori Takayuki , Shiraishi Satoshi 
Published: February 2005

AbstractThe paired tubular accessory glands in Haemaphysalis longicornis open at the junction of the cervical and the vestibular parts of vagina via short and narrow ducts. The pseudostratified columnar glandular epithelium covered by the muscle layer consists of both secretory and supporting cells. As feeding proceeds, the secretory cells increase in volume. In ovipositing females, well‐developed rough endoplasmic reticulum, the Golgi complex, and membranebound granules that are undergoing exocytosis suggest that the secretory cells are involved in protein synthesis. However, in virgin females that fed 10 days, only small dense granules and no secretion activity were observed. The secretions from the tubular accessory gland may be released into the genital tract during the egg passage through the vagina. However, the supporting cells located between the secretory cells become slender during feeding, cohere to each other at the luminal side, and have a very narrow attachment at the basement membrane. Supporting cells probably help maintain secretory cell shape especially during granular discharge into the lumen. © 1994 Wiley‐Liss, Inc.
Epidermal glands in squamata: Fine structure of pre‐cloacal glands in Amphisbaena alba (Amphisbaenia, Amphisbaenidae)
Authors: Antoniazzi M. M. , Jared C. , Junqueira L. C. U. 
Published: February 2005

AbstractThe femoral or cloacal region in lizards and amphisbaenians displays epidermal glands; these are commonly used for purposes of systematics. In spite of being recognized as semiochemical sources (Maderson [1986] Plenum Press, pp. 13–25), their precise role remains uncertain. The glands of lizards are assumed to be principally associated with reproduction and the demarcation of territory. Their function in amphisbaenians remains unknown. The histology of these glands has only been described for lizards. There are no ultrastructural studies of glands of either type. This study concentrates on the fine morphology of the pre‐cloacal glands in Amphisbaena alba using routine histological and ultrastructural techniques. The pre‐cloacal glands of amphisbaenians are, like those of lizards (Chiu and Maderson [1975] J. Morphol. 147:23–40), made up by a layer of germinative cells and various layers of polyhedral cells. The latter display three well‐characterized stages of differentiation. Granules form and pass through two distinct stages. Thereafter, the granules fuse in the third stage. The glandular secretion is formed by cellular units that constitute the plug. Comparison of these morphological data with those available for lizards allows speculation about the function of the glands in amphisbaenians. © 1994 Wiley‐Liss, Inc.
Structure and function of the frontal pit of Lipoptena spp. (Diptera: Hippoboscidae)
Authors: Visagie Elize J. , Schmidt R. 
Published: February 2005

AbstractScanning electron microscopy and histological techniques were used to study the structure and possible function of the frontal pit present in the frons of Lipoptena annalizeae. In the adult fly the opening leads into a closed sclerotized tube (torma) within a sclerite (fulcrum), to which the cibarial pump muscles are attached enabling the retraction of the proboscis. A method for softening the heads of Lipoptena for histological studies is also described. © 1994 Wiley‐Liss, Inc.
Fate and composition of cytopiasmic droplet of hamster epididymal spermatozoa
Authors: Cortadellas Núria , Durfort Merce 
Published: February 2005

AbstractObservations on sperm maturation in the hamster (Mesocricetus auratus) epididymis revealed that the cytoplasmic droplet migrates from the proximal position of the sperm flagellum to the end of the midpiece. This process begins in the testis or vas efferens and ends in the cauda region of the epididymis. A study of different regions of the epididymis and vas deferens demonstrated that the cytoplasmic droplet is not released from the sperm into the luminal fluid. An ultrastructural study of the cytoplasmic droplet demonstrated changes in its morphology as its position moved distally along the midpiece. Membranous components called saccules or vesicles, believed to be remnants of the Golgi apparatus present in the cytoplasmic droplet, changed their morphology during the migration process. Inclusion bodies within vesicles were released to the lumen at the levels of the cauda epididymis and the vas deferens. © 1994 Wiley‐Liss, Inc.
Comparative morphology of caecilian sperm (Amphibia: Gymnophiona)
Authors: Wake Marvalee H. 
Published: February 2005

AbstractThe morphology of mature sperm from the testes of 22 genera and 29 species representing all five families of caecilians (Amphibia: Gymnophiona) was examined at the light microscope level in order to: (1) determine the effectiveness of silver‐staining techniques on long‐preserved, rare material, (2) assess the comparative morphology of sperm quantitatively, (3) compare patterns of caecilian sperm morphology with that of other amphibians, and (4) determine if sperm morphology presents any characters useful for systematic analysis. Although patterns of sperm morphology are quite consistent intragenerically and intrafamilially, there are inconsistencies as well. Two major types of sperm occur among caecilians: those with very long heads and pointed acrosomes, and those with shorter, wider heads and blunt acrosomes. Several taxa have sperm with undulating membranes on the flagella, but limitations of the technique likely prevented full determination of tail morphology among all taxa. Cluster analysis is more appropriate for these data than is phylogenetic analysis. © 1994 Wiley‐Liss, Inc.
Regional and age variations in growing tendon
Authors: Curwin Sandra L. , Roy Roland R. , Vailas Arthur C. 
Published: February 2005

AbstractGastrocnemius tendons of 10 White Leghorn chickens at 6, 8, and 12 weeks of age were divided into proximal, middle, and distal portions to assess regional variability in composition and growth. Body weight increases ∼ 150% during the period examined, whereas the lateral gastrocnemius muscle and tendon increase ∼ 193% and 227%, respectively. No significant changes in cellularity (DNA concentration) or hydroxypyridinium (OHP) crosslinks occur with increasing age. Hydroxyproline (HYP) concentration increases by 12 weeks of age, as hexuronate, glucosamine, and galactosamine decrease. Composition shows some regional variation: the distal region of the tendon has a lower HYP concentration, and increased GAGs and OHP crosslinks compared to either the proximal or middle regions, which do not differ from each other. The mean collagen fibril diameter increases with age, but the oldest tendons also contain more small diameter fibrils (<40 nm). There is a unimodal fibril distribution at all three ages, although this has broadened by 12 weeks. The data from this study suggest that rapid tendon growth occurs throughout the time period examined and that changes characteristic of mature tendon, such as increased OHP crosslink concentration, have not yet developed in hatchlings because of the large amount of new tissue being produced. Whereas all three regions of the tendon are similar in size, composition of the distal region differs from that of the proximal and middle regions, suggesting that this portion of the tendon should be avoided when sampling a tendon. © 1994 Wiley‐Liss, Inc.