Papilla-like Structures Research Articles

Argentophilic structures of the miracidium of Echinochasmus perfoliatus (Trematoda: Echinostomatidae).

Argentophilic structures of the miracidium of Echinochasmus perfoliatus were described from material collected in the vicinity of Vladivostok, Far East of Russia. Impregnated with 0.5% solution of AgNO3 miracidium showed 21 epidermal plates arranged in four rows: 6 + 9 + 4 + 2. Up to 23 papilla-like structures on the terebratorium were arranged along three axes and in four groups. A single papilla was located at the base of each of ventral and dorsal epidermal plates of the first row. Two papillae were located at the base of each of lateral epidermal plates of the first row. The eyespots were located posterior to the first row of plates. Two excretory pores were located anterior to the last row of plates. The results obtained were compared with the argentophilic structures of closely related species of the genus Echinochasmus.

Innervation of developing human taste buds. An immunohistochemical study.

Morphological changes in developing human gustatory papillae during the 6th to the 23rd postovulatory week have been studied. The general innervation pattern of taste papillae and taste bud primordia was revealed immunohistochemically using antibodies against protein gene product 9.5 (PGP9.5), neurofilament H (NFH), neurofilament L (NFL), neurone-specific enolase (NSE), and tubulin. The autonomic and somatosensory nerve supply has been investigated using antibodies against substance P (SP), calcitonin gene-related peptide (CGRP), tyrosine hydroxylase (TH), neuropeptide Y (NPY), the neuronal form of nitric oxide synthase (n-NOS), and, enzyme histochemically, NADPH-diaphorase. Nerve fibers approach the basal membrane of the lingual epithelium around the 7th postovulatory week and invade the epithelium of papilla-like structures at the 8th week, but some also penetrate the basal membrane of the non-papillary epithelium. They are in close contact with slender epithelial cells that are considered to be the taste bud's progenitor cells. Early human taste buds situated at the anterior part of the tongue do not necessarily require a dermal (later fungiform) papilla. The NADPH-diaphorase reaction revealed positive results in dermal nerve fibers, but the immunohistochemical reaction against n-NOS was negative. Immunohistochemical detection of neuropeptides and vasoactive substances rendered negative results for developmental stages of 7-18 postovulatory weeks. By the 18th week, only SP was detected in dermal papillae, but not in the vicinity of taste buds' primordia. Thus, autonomic and somatosensory nerves seem not to play a key role in formation and maintenance of early human taste buds.

Argentophilic Structures of the Miracidium of Echinostoma trivolvis (Cort, 1914) (Trematoda: Echinostomatidae)

Argentophilic structures of the miracidium of Echinostoma trivolvis were described from 80 specimens reared from material originally collected in eastern Pennsylvania, U.S.A. Miracidia were impregnated with 0.5% aqueous silver nitrate solution. The miracidium has 18 epidermal plates arranged in 4 rows of 6 + 6 + 4 + 2 = 18. Up to 20 papillalike structures on the terebratorium were arranged along 3 axes and in 5 groups. A single papilla was located at the base of each of the 6 epidermal plates of the first row. The eyespots were located posterior to the first row of plates and 2 excretory pores were located anterior to the last row of plates.

Development of the gubernaculum and processus vaginalis in freemartinism: further evidence in support of a specific fetal testis hormone governing male-specific gubernacular development.

Freemartinism occurs in some species of ruminants and affects most female bovine fetuses in heterosexual, multiple pregnancies owing to fusion of the chorionic blood circulations soon after implantation. Maldevelopment of the ovaries and Müllerian ducts have been described and recognized as resulting from exposure of their respective primordia to an excess of anti-Müllerian hormone. The present study aimed to analyse the prenatal growth and development of the gubernaculum in freemartins to find out its possible affliction through foetal testis hormones derived from their male co-twin. Histological sections of young and drawings and photographs of further developed freemartins and control male and female bovine foetuses were analysed. The specimens had been collected earlier for analysis of the time course of male and female gonadal and genital development and its impairment associated with freemartinism. The gubernaculum of 35-40-day-old male and female fetuses was in the initial stage of development and of similar appearance in all specimens. Gubernacula of 60-70-day-old male fetuses differed from those of females of similar age in various respects: the male gubernaculum size was larger and extension of the processus vaginalis was deeper. Freemartins showed an intermediate development with some individuals resembling male and others resembling female agemates. During further development, gubernacula in males developed into muscular cremaster sacs, whereas those in females generally did not develop beyond the size and structural complexity of 70-day-old foetuses. Beyond day 70 of fetal life, gubernaculum development in freemartins definitely showed male characteristics with respect to size and growth of a processus vaginalis with a cremaster muscular wall. The male-like pattern of the outgrowth of the processus vaginalis changed during the second half of prenatal life. Rather than its further deepening as in males, this structure became inverted to become emerging as a papilla-like structure from the inguinal abdomen bottom. An explanation is proposed for this unprecedented inversion, taking into account: (1) the faster and higher reaching rightsided ascent of the kidneys and gonads, (2) the femalelike outgrowth of the cranial gonadal suspensory ligaments, and (3) the absence of scrotum development. The ovaries and mesonephric remnants in developing freemartins, during their ascent together with the kidneys while remaining attached to the bottom of the developing processus vaginalis sacs via the gubernaculum ligament, are proposed to act together to pull up the bottom of the processus vaginalis sacs. From this action, "inverted hernia sacs" result as the irreversible consequence. The data support the concept that foetal testes act, via as an yet unidentified third hormone, to establish malelike development of gubernacula into muscular cremaster sacs. Further work is required to reveal the identity of this hormone. Furthermore, the apparent similarity of the freemartins' inverted processus vaginalis sacs and the fetal rodents' gubernacular cones suggests that the ruminants' and rodents' processus vaginalis are essentially similar structures. Thus there is no longer an urgent need to distinguish between two different types of gubernaculum development and testis descent in rodents and ruminants, respectively, and involving or not fetal gubernacular cones. The present observations may thus contribute to the development of a unified hypothesis for sexually dimorphic development of the gubernaculum throughout the mammalian class.

Systematic implications of male caudal morphology in ascaridoid nematode parasites

In view of earlier results, suggesting a considerable stability in the number and distribution patterns of caudal papillae and papillae-like structures in the male of some ascaridoid species, these features are analysed more generally within the superfamily Ascaridoidea. They include the single pair of phasmids on the tail, four pairs of distal papillae some of which are considered in some cases to occur anterior to the level of the cloaca, two pairs of paracloacal papillae, a median papilla or plaque, and numerous pairs of proximal papillae some of which may be situated posterior to the level of the cloaca. The exceptions to this general pattern and the systematic and phylogenetic significance of caudal morphology are discussed.

Piromyces mae and Piromyces dumbonica, two new species of uniflagellate anaerobic chytridiomycete fungi from the hindgut of the horse and elephant

Vegetative thalli, developing sporangia, and zoospores of two new uniflagellate anaerobic chytridiomycete gut fungi, Piromyces mae sp. nov. and Piromyces dumbonica sp.nov., isolated from manure derived from the hindgut of the horse and elephant, respectively, were examined by light and electron microscopy. Piromyces mae differs from Piromyces communis by having papillae-like structures on the sporangium. Piromyces dumbonica differs from P. communis by its C-shaped elongated circumflagellar ring and characteristic organelle distribution in the zoospores. The circumflagellar rings in both new species are tilted at about 10° towards the spur in both prereleased and free zoospores. Three struts in both species connect the circumflagellar ring to the skirt and connective (a newly described perikinetosomal structure) surrounding the kinetosome opposite to the skirt. The connective interconnects the strut, skirt, scoop, kinetosome, and spur. A general model of the kinetosome and perikinetosomal apparatus is proposed for the gut fungi. This model attempts to unify and clarify previous descriptions of the apparatus in these fungi and shows the limited range of variations reported. Key words: gut fungi, Chytridiomycetes, kinetosomes, perikinetosomal apparatus.

Density of Toruli Tactiles in the Goat (Japanese Saanen)

Toruli Tactiles (TT) were clearly observed to be stained with methylene blue solution, and the density of distribution of TT on the body surface was measured in the goat. TT in the goat were present on the hairy skin as papilla-like structure of about 200 to 300 microns in plane-diameter. A high density of TT on the body surface occurred in the areas from the lateral portion of the arm to forearm, and from the thigh to leg. On the other hand, areas of low density of TT were present in the facial-cranial region except for the buccal-masseteric area, cranial-breast, perineum (male), axilla, inguen, carpus-metacarpus, and tarsus-metatarsus. TT were rarely observed in the ears, on the nose, around the mouth, perianal parts, palms and soles.

Timing of a cellular reaction in rice cultivars associated with differing degrees of resistance to Pyricularia oryzae

To clarify the relationship between histological events and lesion formation in incompatible rice and rice blast fungus interaction, penetration frequency, growth of infection hyphae, and cellular reactions were compared in 12 cultivars, each of which showed one of the following four resistant reactions: highly resistant, resistant, moderately resistant, or intermediate. Penetration frequency varied depending on the cultivar, leaf age, and fungal isolate. Papilla-like structures were observed at some unsuccessful penetration sites, but their formation was too restricted to be responsible for the penetration failure of most conidia. Growth of infection hyphae stopped before 24 h in highly resistant cultivars, before 36 h in resistant cultivars, and later than 36 h in moderately resistant cultivars. The growth inhibition of infection hyphae was coincident with the occurrence of a light brown coloration and aniline blue staining of cell walls (B reactions) around infection sites in these cultivars. These results indicate a close relationship between occurrence of B reactions and growth inhibition of infection hyphae and suggest that the time required for B reactions to occur and for growth infection hyphae to stop varies according to degree of host resistance.

Identification of endophytic hyphae of Lophodermium piceae in tissues of green, symptomless Norway spruce needles by immunoelectron microscopy

Antiserum specific for Lophodermium piceae hyphae was obtained by absorbing a rabbit L. piceae antiserum with hyphal material of different fungal isolates. The specificity of this absorbed antiserum was tested with hyphae of endophytic fungi isolated from green, asymptomatic needles of Norway spruce (Picea abies Karst.) using the on-section immunogold labeling technique. With this specific, absorbed antiserum, a homogenous labeling was obtained with cultured hyphae of L. piceae, whereas all other spruce needle endophytes examined remained practically unlabeled. Insignificant cross-reactivity was also observed with needle tissues. The absorbed antiserum was then applied for the immunoelectron microscopical identification of L. piceae hyphae in situ in infected tissues of green, asymptomatic Norway spruce needles. The function of papillalike structures observed in infected needle mesophyll as well as the role of the hyphal sheath surrounding endophytic L. piceae hyphae are discussed in connection with the interaction between L. piceae and asymptomatic Norway spruce needles.

Transitional cells at the junction of seminiferous tubules with the rete testis of the rat: their fine structure, endocytic activity, and basement membrane.

Transitional cells line the intermediate region of rat seminiferous tubules situated between the rete testis and the seminiferous epithelium proper. These tall elongated cells orient themselves in a downstream direction and converge on one another distally in the lumen of the rete testis where they form a distinct papillalike structure through which a narrow patent lumen is apparent. In addition to widely dispersed Golgi apparatus and mitochondria, these cells contain an abundance of microtubules, cisternae of endoplasmic reticulum, and a distinct lobulated nucleus showing clumps of chromatin and a prominent nucleolus. The endocytic activity of these cells was examined by employing adsorptive (cationic ferritin, concanavalin A ferritin) and fluid-phase tracers (native ferritin, horseradish peroxidase-colloidal gold complex, and concanavalin A ferritin in presence of alpha methyl-D-mannoside). Such tracers were injected separately into the lumen of the rete testis, and the animals were killed at 2, 5, 15, and 30 min and 1, 2, and 6 hr after injection. At 2 min, both adsorptive and fluid-phase tracers were found within coated and uncoated pits of the apical plasma membrane of these cells as well as in large, subsurface, uncoated spherical, C-shaped, and tubular membranous elements. At 5 min the tracers were seen in endosomes of different sizes; while at 15 min and 30 min, pale and dense multivesicular bodies of small and large sizes, respectively, were labeled. At 1-hr and longer time intervals secondary lysosomes became labeled. While both fluid-phase and adsorptive tracers followed the same pathway and fate, binding to the apical and lateral plasma membranes of the transitional cells and to the membrane delimiting coated and uncoated pits was observed only with the adsorptive tracers. These results demonstrate that the transitional cells are actively involved in both fluid-phase and adsorptive endocytosis, which may play an important role in modifying the composition of the luminal fluid. The transitional cells of the distal zone of the intermediate region rest on an elaborate basement membrane (BM) complex which includes a thin BM immediately underlying these cells, a thick distal layer of BM, and strands of BM spanning the distance between the two in the form of a loose anastomotic network. Use of antisera against heparan sulfate proteoglycan, laminin, and type IV collagen revealed the presence of all three components within all areas of the BM complex. In the meshes of the anastomotic BM network, extracellular vesicles were observed.(ABSTRACT TRUNCATED AT 400 WORDS)

Scanning and transmission electron microscopic studies of the surface of Vallisia indica (Monogenea, Polyopisthocotylea)

Ultrastructural studies were carried out on the surface of Vallisia indica, found on the gills of Scomberoides commersonianus in the Indian ocean. Tegumental serrations present on the hump and on the dorsal and ventro-lateral surfaces of the hindbody lie in the same plane as the secondary gill lamellae and may provide anchorage against displacement forces. Elsewhere the tegument is highly folded forming a reticulum of lamellae and microvilli. The surface syncytium of the tegument in the region of the serrations possesses fibrous electron-dense bars, and a continuous fibrous electron-dense terminal web is present beneath the apical plasma membrane in all regions. The haptor consists of two asymmetrical rows of pincer-type clamps and a terminal lappet with a pair of hooks. Each clamp may be withdrawn into a cushion-like pad. Uniciliated sensory structures are found around the mouth and on the body surface, whereas non-ciliated papillae-like structures are present on the haptor and hindbody. A pair of cone-like sensilla is present on the lappet.

The surface topography of Bicotyle vellavoli (Monogenea) from the gills of Pampus chinensis

Ramasamy P. and Hanna R.E.B. 1986. The surface topography of Bicotyle vellavoli (Monogenea) from the gills of Pampus chinensis. International Journal for Parasitology 16: 591–594. The haptor possesses two dissimilar rows of clamps. On one side of the haptor a few large sucker clamps occur while on the other side, a greater number of small pincer-type clamps of uniform size are present. The mouth opens subterminally on the ventral surface. The common genital aperture occurs midventrally while the vaginal pore opens on the dorsal surface. Transverse annulations and tegumental protrusions are present on the body surface of Bicotyle vellavoli but microvilli are absent. Uniciliated sensory structures, presumably rheoreceptors or tangoreceptors occur on the body surface. In contrast, the clamps bear non-ciliated domeshaped papilla-like structures.

Increased papilla formation, a major factor of induced resistance in the barley – Erysiphe graminis f.sp. hordei system

Using two barley cultivars, 'Hanna' and 'Russian No. 12', resistance to Erysiphe graminis DC. f.sp. hordei Em. Marchal induced by preliminary inoculation with a compatible or an incompatible race of the powdery mildew fungus was examined with respect to cellular responses. When the primary leaves of barley seedlings were preliminarily inoculated with a compatible or an incompatible race on the abaxial leaf surface, they became resistant to the disease caused by challenge inoculation with the same pathogen on the adaxial surface. The resistance induced was expressed as decrease of fungal penetration and restriction of hyphal growth. These phenomena seemed to be attributable to the increase of papillae or papillalike structures which do not seem to be responsible for the race-specific resistance. On the basis of these results, it is suggested that the resistance induced may be different from race-specific resistance.

Occurrence of tyloses and their ultrastructural differentiation from similarly configured structures in American elm infected by Ceratocystis ulmi

Tylosis formation in American elm was sparse during development of Ceratocystis ulmi infection in the period of highest tree susceptibility, as observed in numerous periodically sampled field-inoculated trees from 1970–1978. Tyloses are more frequent in greenhouse-grown than in field-grown trees. They are abundant, sometimes in invaded vessels, in field samples collected after acute wilting (in surviving trees) at the end of summer or during the following spring. Aborted, collapsed, or disintegrated tyloses have been observed. The first tylosis wall layer (continuous with the protective layer of the parenchyma cell) is thickened in some tyloses; papilla-like structures are present in others. Often, masses of osmiophilic material are located outside the tylosis, with strands extending into the tylosis wall. An almost translucent, often lamellate layer is deposited in more mature tyloses.Other structures having the external configuration of tyloses but differing from them in organization, form abundantly in vessels shortly after inoculation in both greenhouse- and field-grown trees. Called bubbles, these structures are similar to, and often in continuity with, a coating on inner vessel walls.These observations are discussed in relation to previous ultrastructural observations of infected elms and in general with other plant wilts of fungal origin.

The surface structure of the completely and incompletely orthokeratinized oral epithelium in the rat: a light, scanning and transmission electron microscope study.

Mucosa from the hard and soft palates, molar gingiva, cheek and dorsal surface of the tongue of the rat was examined in the light microscope, following Mallory's triple connective tissue stain, and in the scanning and transmission electron microscopes. The epithelium covering the hard palate, gingiva, the smooth band of mucosa at the junction of the hard and soft palates, intermediate zones of the soft palate, fungiform papilla-like structures in the central zone of the soft palate, the fungiform papillae, and the more superficial part and posterior surfaces of the filiform papillae of the tongue all exhibited complete orthokeratinization. The oral surfaces of the epithelial cells in all these areas had a honeycomb pattern of interconnecting ridges surrounding depressions. Imprints of the overlying cells that had been desquamated were apparent, and the lateral boundaries between the cells were formed by two raised ridges separated by a gap. The epithelium covering the cheek, central zone of the soft palate apart from the fungiform papilla-like structures, lateral zones of the soft palate, gingival crevice, and the mucosa between the fungiform and filiform papillae of the tongue all exhibited incomplete orthokeratinization. The oral surfaces of the epithelial cells in all these areas were relatively smooth and did not exhibit a honeycomb pattern of interconnecting ridges. Imprints of the overlying cells that had been desquamated and the lateral boundaries between the cells were only very occasionally found. In the transmission electron microscope the outlines of the cells were compatible with the surface patterns seen in the scanning electron microscope. The possible relationships between the degree of orthokeratinization and ultrastructure of the various epithelia are discussed.

Growth abnormalities in microorganisms exposed to tobacco leaf extracts.

Unusual cultural changes were observed when several bacterial and yeast strains were grown on a medium containing aqueous extracts of tobacco leaves. In 24–48 h incubation on such a medium, several dark-brown papilla-like structures developed on the surface of normally smooth colonies. Moreover, smaller dark-brown refractile globular bodies were observed in the medium in areas beneath and surrounding the microbial colonies with papilla-like structures. Attempts to demonstrate the viability of these globular bodies failed. The cultural abnormalities observed on tobacco extract medium were unique to this medium since they were not detected in a wide variety of culture media tested. The lowest concentration of tobacco extract (dry wt. basis), which is required for the development of this phenomenon, was determined to be 0.5 mg/ml of medium.

Skin Tags and Ventral Melanism in the Rio Grande Leopard Frog

Leopard frogs from the lower Rio Grande valley of Texas and Mexico normally have mottled throats and pectoral areas which distinguish them from other species of leopard frogs in the United States. Varying melanism of the undersurfaces is due in part to pigment con- centration and dispersion in melanophores under environmental changes. We conclude that these features among others characterize Rana berlandieri Baird and that the species is primarily a Mex- ican member of the pipiens complex. About 1 percent of the Rio Grande population is afflicted with papilla-like structures, termed skin tags, as the result of wounding. A yellow-legged population, believed to be of the same species, occurs in the state of Sina- loa of western Mexico, for which the name forreri Boulenger is available. It is concluded that Rana berlandieri is a Mexican species with several subspecies encircling the central plateau (ex- cept to the north) and entering the United States on its southern borders. This postulates two separate groups of leopard frogs, those in the United States being referred to as Rana pipiens with its subspecies and those of Mexico as Rana berlandieri with its subspecies. * * *

Regeneration of taste buds in the lingual epithelium after excision of the vallate papilla

Taste buds in the tongue are found in the epithelium of gustatory papillae and not in the surrounding epithelium. The buds disappear after denervation, and after reinnervation they appear only in the epithelium of the papilla. In the present study, the vallate papilla was excised in order to determine whether the remaining lingual tissue could regenerate a papilla and taste buds. Innervated and denervated tongues of adult rats were studied 40, 100, and 200 days after excising the papilla. Although papillalike structures were occasionally found, at no time was there definite evidence of normal papilla formation. Furthermore, these structures were similar in the innervated and denervated tongues, so that the nerve played no significant role in their development. Taste buds, however, did appear at all postoperative time intervals but only in the innervated tongues. The buds were present on the top surface of the tongue or in shallow grooves. The results demonstrate that epithelium other than that covering the vallate papilla can give rise to taste buds and that taste bud development does not depend on the presence of a papilla. I concluded that the nerve-epithelial interaction that results in taste bud formation does not require the presence of the original gustatory epithelium or papilla.