bluuebunny/crossref_metadata_2025_split huggingface dataset:
Origin and formation of the royal fat body of the higher termite queens
Authors: Han Sun Heat , Bordereau Christian 
Published: February 2005

AbstractThe formation of the royal fat body was studied by electron microscopy in three species of higher termites (Macrotermes bellicosus, Macrotermes subhyalinus, and Cubitermes fungifaber). The swarming alate imago has a storage fat body typical of most insects. In non‐physogastric young queens, during the fasting period, the adipocytes deplete their reserves and then, along with the increased vitellogenesis, acquire protein‐synthesizing structures (R.E.R.). During the development of physogastry they progressively specialize in protein synthesis and secretion and undergo many cell divisions. The cytological change is paralleled by a spatial reorganization of the fat body. Observations on the transformation of imaginal adipocytes into royal adipocytes show that the royal fat body is derived from the imaginal fat body and not from the tracheal cells as previously claimed.
Histological and enzyme histochemical studies on the nephrons of the freshwater fishes, Cyprinus carpio and Carassius auratus
Authors: Endo Makoto , Kimura Masao 
Published: February 2005

AbstractThe nephrons of carp (Cyprinus carpio) and goldfish (Carassius auratus) were examined histologically and also histochemically for enzymes. In both species the distal and collecting tubules have much wider lumens than do the other renal tubules; thus urine probably flows more slowly in these larger tubules. Enzyme histochemistry shows that epithelium of the neck and proximal and intermediate tubules respires anaerobically. whereas that of the distal and collecting tubules respires aerobically. The distribution of Na‐K‐ATPase in the distal and collecting tubules indicates that they also transport sodium actively. The slow flow of urine and the energy produced by aerobic metabolism probably increase the efficiency of active transport.
Gut‐Associated lymphoid tissue (GALT) in the amphibian urodele Pleurodeles waltl
Authors: Ardavin C. F. , Zapata A. , Villena A. , Solas M. T. 
Published: February 2005

AbstractEven though salamanders are supposed to lack intestinal lymphoid tissue, Pleurodeles waltl shows lymphoid aggregates throughout the gut, especially in the small intestine, as cell infiltrates in the lamina propia. They have a phylogenetic significance in relation to the existence of an intestinal immunologic barrier in vertebrates.
Setiferous structures of male coleoptera
Authors: Faustini D. L. , Halstead D. G. H. 
Published: February 2005

AbstractA scanning electron microscopy study was made of the male setiferous sex patches and analogous structures in 11 families of Coleoptera (Anthribidae, Bruchidae, Ciidae, Cleridae, Coccinellidae, Dermestidae, Leiodidae, Ptinidae, Staphylinidae, Tenebrionidae, and Ostomatidae). These secondary sexual characters appear to have several features in common including relatively long, often ridged, setae, cuticular ducts (frequently cribriform pore plates), and the production of a secretion. It is suggested that these structures may all be concerned with the production, release, and dissemination of pheromones.
An electromyographic study of the function of the jaw adducting muscles inVaranus exanthematicus(varanidae)
Authors: Smith Kathleen K. 
Published: February 2005

AbstractThe function of major features of the skull ofVaranus exanthematicusduring feeding was examined using cineradiography and electromyography. During the initial stages of feeding,Varanusgrabs and orients a prey item in the mouth with no mastication, tearing of the prey, or killing bite. Ingestion is through a highly stereotyped movement, inertial feeding. The tongue plays no role in food transport. Once the prey is in the pharyngeal region, the hyoid apparatus squeezes the prey into the esophagus and stomach. Activity of jaw adducting muscles during prey orientation and inertial feeding is strikingly different. In prey orientation, the adductor musculature is active over long periods, and intermuscular differentiation and unilateral activity are common. During these phases the musculature is producing force against the resistance of the prey item held between the teeth. In inertial feeding, the jaw musculature functions to close the jaws rapidly against little resistance. A consistent pattern of intramuscular differentiation is present, with some portions of the musculature being active during both jaw opening and closing. Activity of the Mm. adductor mandibulae externus and pterygoideus is indistinguishable. Neither meso‐ nor metakinetic movement was observed during inertial feeding; resolution of interacranial movement was less certain during power phases. The quadrate moved during jaw opening and closing in inertial feeding. However, its movement was not linked with that of the palatomaxillary segment. These data are discussed in three contexts: cranial kinesis, intramuscular differentiation, and the mechanics of whole muscles.
An ultrastructural analysis of the mature spermatozoon of Anguispira alternata (say) (pulmonata, stylommatophora)
Authors: Atkinson James W. 
Published: February 2005

AbstractMature spermatozoa from the hermaphroditic duct of adult snails were examined using various techniques of light microscopy as well as scanning and transmission electron microscopy. The sperm are approximately 557 μm in length including a dextrally spiral head approximately 13 μm long. The head consists of an electron‐dense nucleus sculptured into a double‐ridged spiral and an acrosome projecting approximately 0.45 μm beyond the apex of the nucleus. The acrosome consists of a membrane‐bound vesicle approximately 0.1 μm in diameter and a column of homogeneous material which extends along one side of the terminal spiral of the nucleus. This material is separated from the nucleus by the nuclear envelope. The neck region, though similar to that found in other pulmonates, possesses a unique coiled structure surrounding the central doublet of the axoneme. The midpiece axoneme possesses a 9+9+2 configuration anteriorly grading into a 9+2 pattern for the majority of its length. There are three mitochondrial helices – one primary and two secondary – in the midpiece. Only the primary helix persists throughout the midpiece.
The ultrastructure of spermatogenesis in Labidocera aestiva (copepoda: Calanoida)
Authors: Blades‐Eckelbarger P. I. , Youngbluth M. J. 
Published: February 2005

AbstractThe fine structure of spermatogenesis is described for the marine calanoid copepod Labidocera aestiva. The mature spermatozoon is a slightly flattened, disc‐shaped cell without a flagellum or an acrosome.Primary spermatocytes in first meiotic prophase are characterized by large nuclei showing progressive condensation of chromatin. The cytoplasm contains free ribosomes, numerous mitochondria, cytoplasmic vesicles, centrioles, and perinuclear nuage. Densely staining cisternae are associated with the nuage of pachytene and diplotene primary spermatocytes. This association may represent the temporary differentiation of an acrosome. Synaptonemal polycomplexes are frequently present in the nuclei of zygotene, pachytene, and diplotene primary spermatocytes. Many of the intercellular bridges which join the germ cells throughout spermatogenesis appear occluded by systems of transverse membranous cisternae. After the second meiotic telophase, spermatids are incorporated into nongerminal accessory cells that may facilitate the release of spermatids from the testis and regulate the rate of spermatogenesis by phagocytosis.During spermiogenesis the mitochondria become closely applied to the nuclear envelope, the nuclear envelope fragments and forms an elaborate membrane complex, a pentalaminar plasma membrane develops, and electron‐dense material accumulates on the inner and outer surfaces of the plasma membrane in the mature spermatozoon.
Arterial retia related to supply of the central nervous system in two small toothed whales– narwhal (Monodon monoceros) an beluga (Delphinapterus leucas)
Authors: Vogl A. W. , Fisher H. D. 
Published: February 2005

AbstractWe have studied the comparative anatomy of arterial plexuses (retia mirabilia) related to supply of the central nervous system in two closely related species of toothed whales – narwhal (Monodon monoceros) and beluga Delphinaterus leucas). In both species, retia originate from major vessels in the neck, thorax, and lumbar regions, then extend into the neural canal and cranium to supply the spinal cord and brain. The system generally consists of arteries embedded in á matrix of fatty connective tissue. Constituent vessels are only occasionally reated to veins or venous sinuses. Though retial anatomy is similar in the two species, there are two related features that appear species specific: (1) amount of retia originating from the supreme intercostal arteries and (2) thoracic retial size. Both are larger in the narwhal, as are values for hematocrit and hemoglobin concentration, which, in this study, we use as indices of diving ability. Our data are consistent with the hypothesis that the retia are in some way linked to diving ability. The nature of this link is not known; however, we discuss our results in the context of the most popular hyotheses of retial function.
Hamster nasal glands: Their structure, sialic acid content, and vulnerability to actinomycin D
Authors: Adams Don R. 
Published: February 2005

AbstractThis study examines the structure of mucosal glands in the walls of the hamster maxillary recess, compares the histochemical appearance of nasal glands to their sialic acid content, and determines the vulnerability of nasal glands to actinomycin toxicity. Observations were made on plastic‐embedded tissue with light and transmission electron microscopes. Determinations of total sialic acid in mucosal samples were conducted with thiobarbituric acid. Experimental hamsters were administered 0.2 μg of actinomycin D (IP)/gm body weight/day for five days. Types of granules present in the lateral nasal gland (LNG) and glands of the maxillary recess (MRGs) include: 2.0 μm lightly basophilic, lightly electron‐dense granules and 1.5 μm strongly basophilic, electron‐dense granules in the same acinar cell type in both the LNG and MRGs; 1.5 μm metachromatic granules in some acinar cells of the LNG; 1.0 μm moderately electron‐dense granules in cells of MRG ducts; and 0.7 μm electrondense granules in cells of LNG intercalated ducts. Acid glycoproteins, demonstrable by histochemistry, are present in the LNG but not in the MRGs. However, the total sialic acid content of tissues from MRG tissue is greater than that of other tissues measured. A minor number of LNG acini, those with metachromatic granules, have branching basal cytoplasmic projections. Many dark cells are present in striated ducts of the LNG. Histological alteration due to actinomycin‐D toxicity, conspicuous in parotid salivary parenchyma, is greater in MRG than in LNG tissue.
Osteocranial development in the viviparous surfperch Amphistichus argenteus (pisces: Embiotocidae)
Authors: Morris Steven L. , Gaudin Anthony J. 
Published: February 2005

AbstractThe development of the cranial and branchial skeleton of the surfperch Amphistichus argenteus, a member of the family Embiotocidae, is described, and phylogenetic and functional aspects of the skull development of this species are discussed. The earliest bones to appear are those dermal elements of the branchial skeleton involved with feeding, and the bones, both dermal and endochondral, located in the basicranial region of the neurocranium. These are followed by dermal bones associated with the lateral line system and finally by the remainder of the bones of the branchial skeleton and the cartilaginous bones of the otic capsules. The last bone to develop is the ethmoid.
Transformations of osteoclast phenotype in ia rats cured of congenital osteopetrosis
Authors: Marks Sandy C. , Schneider Gary B. 
Published: February 2005

AbstractThe reduced bone resorption characteristic of osteopetrosis is accompanied in the incisors‐absent (ia) rat mutation by a significant increase in osteoclasts of inactive (mutant) phenotype. Restoration of bone resorption in ia rats by transfer of spleen cells from normal littermates is preceded by a transformation of osteoclasts from mutant to normal phenotype.In this investigation the proportions of osteoclasts of normal phenotype have been determined by light microscopy in untreated ia and normal rats and in ia rats treated with various cell populations from normal rats. Significant increases in numbers of osteoclasts of normal phenotype were seen in the mutant skeleton soon after cell treatments that eventually restored bone resorption and cured the disease. No changes in osteoclast phenotype were seen after cell transfers that did not cure the disease.These data establish transformation of osteoclast phenotype as an early event in the recovery from osteopetrosis and suggest that determination of osteoclast phenotype is a reliable predictor of the success of normal cell populations to restore bone resorption in this mutation.
Functional morphology of the head of the inertial suction feeding butterflyfish, Chaetodon miliaris (perciformes, chaetodontidae)
Authors: Motta Philip Jay 
Published: February 2005

AbstractThe structure and mechanism involved in jaw movements are described for an inertial high‐speed suction feeding fish, Chaetodon miliaris. Jaw biomechanics were studied by (1) manipulation of live and fresh‐killed specimens, (2) electrical muscle stimulation of anesthetized live specimens, (3) connective tissue severance experiments of fresh‐killed and live anesthetized specimens, and (4) cine photography of live unimpaired and surgically impaired specimens.Three couplings appear to be involved in jaw opening: a levator operculi‐opercular‐interopercular‐mandible coupling; and epaxial complex and/or hypaxial/sternohyoideus complex‐hyoid apparatus‐uncontracted protractor hyoideus‐mandible coupling. Jaw opening, protrusion, closing of the protruded mouth, and jaw retraction occur in 60–110 msec. Jaw protrusion coincides with mandible depression during opening of the mouth. Closure of the protruded mouth is apparently the result of contractions of pars A1 and A2 of the adductor mandibulae muscle. Pars A3 and Aw may induce retraction of the jaws in the closed‐protruded state. Jaw closure in the retracted, nonprotruded state may involve all branches of the adductor mandibulae.The importance of these findings is discussed in light of previous studies as are some proposed functions of jaw protrusion in this species.
Structural characterization of the hemocytes of Plodia interpunctella
Authors: Beeman Sylvia C. , Wilson Marijo E. , Bulla Lee A. , Consigli Richard A. 
Published: February 2005

AbstractSix types of hemocytes were identified in fifth instars of the Indian meal moth, Plodia interpunctella. The morphology of these cells was characterized by phase contrast and electron microscopy, with Sudan black B, Giemsa, Janus green B, and periodic acid‐Schiff staining. Reaction of the hemocytes with seven fluorescing lectin conjugates revealed distinctive binding patterns by their plasma and nuclear membranes and cytoplasmic inclusions. A direct line of descent from prohemocytes to plasmatocytes to granulocytes is suggested from these morphological observations.
Extraordinary fossorial adaptations in the oligocene palaeanodonts Epoicotherium and Xenocranium (Mammalia)
Authors: Rose Kenneth D. , Emry Robert J. 
Published: February 2005

AbstractNew fossils of the rare Oligocene mammals Xenocranium and Epoicotherium add information on their skulls and provide the first information on their postcranial skeletons. These epoicotheres, the latest surviving palaeanodonts, have numerous fossorial adaptations and must have been predominantly subterranean. Their skeletal specializations are similar to, and equal or surpass in degree of development, those of most living fossorial mammals.Principal modifications of the skull are the expanded, domed occiput with broad lambdoid crests, hypertrophy of the malleus‐incus and related changes in other ear components, reduced eyes, and (in Xenocranium) a flaring, upturned, spatulate snout. The neck was strengthened by synostosis of the 2nd through 5th cervical vertebrae. The forelimb elements have exaggerated crests, processes, and fossae for muscles used in digging or in stabilizing certain joints. The scapula has a high, stout spine with bifid acromion, a “secondary spine,” and an expanded postscapular fossa for attachment of the teres major muscle. The humerus has an elongate pectoral crest, large lesser tuberosity, long entepicondyle, and large hooklike supinator crest. The enormous incurved olecranon process of the ulna provided insertion for the massive triceps and origin for the carpal and digital flexors, and the latter gained mechanical advantage by incorporating in its tendon a large carpal sesamoid. In the greatly shortened hand, digit three is largest, with its metacarpal and proximal phalanx fused and its claw‐bearing ungual‐phalanx very large.These traits indicate that Xenocranium and Epoicotherium were among the most specialized “rapid‐scratch” diggers ever to evolve. Their remarkable convergence to chrysochlorids reflects a similar mode of digging, with extensive use of the snout for loosening and lifting soil when making shallow foraging burrows. For deeper burrowing, the forelimbs probably loosened the soil while the rear limbs moved it behind. Like many extant subterranean mammals, Xenocranium and Epoicotherium were essentially sightless, but they were specialized for low frequency sound reception. Their extinction may have been due to a combination of environmental change and competition with other fossorial animals, such as proscalopine insectivores and rhineurid amphisbaenians.
Digestive anatomy of Halella azteca (Crustacea, Amphipoda)
Authors: Schmitz Eugene H. , Scherrey Patricia M. 
Published: February 2005

AbstractThe digestive tract of the freshwater amphipod Hyalella azteca is a straight but differentiated tube consisting of foregut, midgut, and hindgut divisions. The foregut is subdivided into a tubular esophagus, a cardiac stomach, and a pyloric stomach. The cuticular lining of the cardiac stomach is elaborated into a set of food‐crushing plates and ossicles, the gastric mill, while the pyloric cuticle forms a complex straining and pressing mechanism. Nine caeca arise from the midgut, seven anteriorly and two posteriorly. Four of the anterior caeca, the hepatopancreatic caeca, are believed to be the primary sites of digestion and absorption. The remaining caeca may be absorptive, secretory, or both. The much‐folded hindgut wall is capable of great distention by extrinsic muscle action for water intake to aid in flushing fecal material out of the anus; such action also may stimulate antiperistalsis by intrinsic rectal muscles.
The mechanism of forearm rotation in Varanus exanthematicus
Authors: Landsmeer Johan M. F. 
Published: February 2005

AbstractIn the sprawling gait of Varanus exanthematicus, the bicondylar distal humerus requires both the radius and ulna to rotate in the same direction. The joints between the radius and radiale and between the ulna and ulnare and pisiform accomodate these specific rotations. A ligament system between radius, ulna, radiale, and ulnare causes the radius and ulna to approximate one another during external rotation of the forearm. This approximation is conveyed distally resulting in a narrowing of the hand during external rotation of radius and ulna or during pronation of the free hand. The significance of these and related linkages is discussed.
Seasonal changes in the ultrastructure of the kidney collecting tubule in the lizard Podarcis ( = Lacerta) taurica
Authors: Gabri M. S. 
Published: February 2005

AbstractIn female Podarcis taurica the kidney collecting tubule always consists entirely of mucous‐secreting cells. In males it has a seasonally variable sexual segment and a non variable mucous‐secreting segment. In April the sexual segment is composed of columnar cells with cytoplasm rich in ribosomes and Golgi bodies and apical clusters of large vesicles with fibrous contents. The terminal region of the sexual segment also has pillar‐shaped cells resembling those of the mucous‐secreting segment. By May the accumulation of apical vesicles reaches a maximum, and many cells have apparently extruded their secretion into the lumen. In July all the cells are pillar shaped with dilated endoplasmic reticulum but with few apical vesicles. In September the sexual segment has some cells resembling those of the mucous‐secreting segment and others the sexual segment pillar cells in April. It is suggested that during sexual activity in the spring the sexual segment secretes a spermatozoon‐nutrient protein but subsequently reverts to mucous secretion. The non variable mucous‐secreting regions in both males and females consist of mucous, intermediate, and dark cells. Mucous cells have apical masses of closely packed droplets, whereas dark cells have dense cytoplasm and small, loosely associated apical vesicles. Intermediate cells have some dark cell features but mucous cell apical vesicles. The dark, intermediate, and mucous cells probably represent activity states of a single type. The mucous secretion is interpreted as a protective material which lines the urinary passage and coats the secreted solid urates. Elaborated intercellular spaces in the mucous‐secreting regions may indicate a water absorption capacity in urine concentration.
The functional anatomy of the shoulder of the savannah monitor lizard (Varanus exanthematicus)
Authors: Jenkins Farish A. , Goslow G. E. 
Published: February 2005

AbstractThe excursions of the scapulocoracoid and forelimb and the activity of 18 shoulder muscles were studied by simultaneous cineradiography and electromyography in Savannah Monitor lizards (Varanus exanthematicus) walking on a treadmill at speeds of 0.7–1.1 km/hour. During the propulsive phase, the humerus moves anteroposteriorly 40–55° and rotates a total of 30–40°. Simultaneously, the coracoid translates posteriorly along the tongue‐and‐groove coracosternal joint by a distance equivalent to about 40% the length of the coracoid.Biceps brachii, coraco‐brachialis brevis and longus, the middle and posterior parts of the latissimus dorsi and pectoralis, serratus anterior, serratus anterior superficialis, subscapularis, supracoracoideus, and triceps usually become active during the late swing phase and continue activity throughout most or all of propulsion. The anterior part of the latissimus dorsi is active during the transition from propulsive to swing phases. Brachialis, deltoideus scapularis, levator scapulae, the anterior part of pectoralis, scapulo‐humeralis posterior, and subcoracoideus are active primarily during the swing phase; they are occasionally active during propulsion. Deltoideus clavicularis, scapulo‐humeralis posterior, sternocoracoideus, and the posterior part of the trapezius are biphasic, with activity in both the propulsive and swing phases.A number of shoulder muscles in Varanus exanthematicus and Didelphis virginiana (the Virginia opossum) are similar in attachments, in activity patterns with respect to phases of the step cycle, and in apparent actions. These similarities are interpreted as a pattern inherited from the ancestors of higher tetrapods. The sliding coracosternal joint permits an increase in step length without demanding greater excursion at the shoulder and elbow joints.