Biomedical subjects

Y Atoji

Publications and source records attributed to Y Atoji.

At least 19 recordsLinked to original sources

PubMed2006

Morphology of the intermandibular gland of the Lesser mouse deer, Tragulus javanicus.

The morphology of the intermandibular gland of the Lesser mouse deer (Tragulus javanicus), which plays an important function in marking area and territory and in the reproductive behaviour of the animal, was examined using immunohistochemistry, lectin histochemistry and scanning electron microscopy. The gland was composed of sebaceous and apocrine glandular material. Sebaceous glands occupied a greater area of the total gland and consisted of many large lobules with polyhedral cells having a pale cytoplasm. The sebaceous gland, being holocrine, possessed no special secretory ducts. The apocrine gland was lined by cuboid cells and the secretory products were often seen in the apical portions of the cells. Myoepithelial cells contained actin filaments lining the basal membranes of the apocrine gland and were surrounded by nerve fibres which immunostained with protein gene product 9.5. The secretion of the gland appears to be a mixture of larger amounts of lipid material from sebaceous glands, and glycoconjugates secreted by both sebaceous and apocrine glands. Lectin histochemistry detected these as galactose, N-acetyl-D-galactosamine, N-acetyl-D-glucosamine, D-mannose and D-glucose. The male gland was larger in size and contained more N-acetyl galactosamine and N-acetyl glucosamine in its secretion than the gland of the female. This implied the presence of sexual differences in secretions in the intermandibular gland of the Lesser mouse deer.

Animals↗

PubMed2004

Mechanisms of the hypoglycaemic and immunopotentiating effects of Nigella sativa L. oil in streptozotocin-induced diabetic hamsters.

The aim of this study was to elucidate the mechanisms underlying the hypoglycaemic effect of N. sativa oil (Nigella sativa oil) in streptozotocin (STZ)-induced diabetic hamsters, in terms of hepatic glucose production, and to investigate the possible immunopotentiating effect of N. sativa oil on peritoneal macrophages. Diabetes was induced by intraperitoneal injection of 65 mg/kg body weight of STZ. Treatment with N. sativa oil commenced 6 weeks after induction of diabetes at a dose of 400 mg/kg body weight by gastric gavage. Isolated hepatocytes were collected using collagenase to determine liver glucose production. Phagocytic activity was evaluated by injection of fluorescent latex (2 microm diameter) intraperitoneally, followed 24 h later by collection of peritoneal macrophages. N. sativa oil reduced blood glucose from 391+/-3.0 mg/dl before treatment to 325+/-4.7, 246+/-5.9, 208+/-2.5 and 179+/-3.1 mg/dl after the first, second, third and fourth weeks of treatment, respectively. Hepatic glucose production from gluconeogenic precursors (alanine, glycerol and lactate) was significantly lower in treated hamsters. Treatment with N. sativa oil significantly increased the phagocytic activity and phagocytic index of peritoneal macrophages and lymphocyte count in peripheral blood compared with untreated diabetic hamsters. Our data indicate that the hypoglycaemic effect of N. sativa oil is due to, at least in part, a decrease in hepatic gluconeogenesis, and that the immunopotentiating effect of N. sativa oil is mediated through stimulation of macrophage phagocytic activity either directly or via activation of lymphocytes.

Adjuvants, Immunologic↗

PubMed2002

Isulinotropic properties of Nigella sativa oil in Streptozotocin plus Nicotinamide diabetic hamster.

The present study was designed to investigate the possible insulinotropic properties of Nigella sativa L. (N. sativa) oil in Streptozotocin plus Nicotinamide-induced diabetes mellitus in hamsters. Nicotinamide was injected intraperitoneally 15min before injection of Streptozotocin intravenously. Oral treatment with N. sativa oil began 4 weeks after induction of diabetes. Serum insulin was measured by enzymeimmunoassay. Islets insulin was stained using anti-insulin monoclonal antibody. Significant decrease in blood glucose level together with significant increase in serum insulin level were observed after treatment with N. sativa oil for 4 weeks. Big areas with positive immuno-reactivity for the presence of insulin were observed in the pancreases from N. sativa oil-treated group compared to non-treated one using immunohistochemical staining. Therefore, our data show that the hypoglycemic effect of N. sativa oil in Streptozotocin plus Nicotinamide diabetic hamsters resulted, at least partly, from a stimulatory effect on beta cell function with consequent increase in serum insulin level. These results indicate that N. sativa oil has insulinotropic properties in type 2-like model.

Animals↗

PubMed2001

Avian-to-mammal transmission of an avian rotavirus: analysis of its pathogenicity in a heterologous mouse model.

It has been suggested that group A avian rotaviruses can be transmitted to mammals, but there is no direct evidence that such viruses induce disease in mammals. Suckling mice were orally inoculated with two avian rotaviruses. A pigeon rotavirus, PO-13, was found to induce diarrhea, but a turkey rotavirus, Ty-3, did not. The diarrhea induced by PO-13 was dependent on the age of the mouse. In histopathological examinations, antigens of PO-13 were sporadically detected in absorptive cells in the ileum, and lesions were observed as ballooning degenerations of absorptive cells in a region from the duodenum to the ileum. However, the rotavirus antigen was not detected in the majority of these degenerative cells. These results indicated that PO-13 could infect and induce diarrhea in suckling mice. This is the first evidence of an avian rotavirus being experimentally transmissible to a mammal.

Animals↗

PubMed2001

Distribution of NADPH diaphorase-containing neurons in the pigeon central nervous system.

The aim of the present study was to determine the distribution of nitric oxide-synthesizing neurons in the pigeon brain and spinal cord. Tissue sections were stained for reduced nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d). In the telencephalon, intensely stained neurons with dendrites extending distally were seen in most regions. The ectostriatum was characterized by intensely and diffusely stained neuropil. In the diencephalon, intensely positive neurons were seen in the lateral hypothalamic region and lateral mammillary nucleus. In the mesencephalon, intensely stained, multipolar neurons were abundantly scattered in the central gray, nucleus intercollicularis, reticular formation, nucleus tegmenti pedunculo-pontinus, pars compacta, area ventralis of Tsai, and ansa lenticularis. In the rhombencephalon, positively-stained neurons were found in the pontine nuclei and reticular formation. The cerebellar cortex, except for Purkinje cells, was a preferential region for NADPH-d activity. Positive end-bulbs made contact on somata in the nucleus magnocellularis cochlearis. In the spinal cord, NADPH-d positive neurons were seen in layer II and the marginal nucleus. Our results demonstrated that the distribution of NADPH-d-containing neurons in the pigeon brain and spinal cord is more complex than in other avian species. Our findings indicate that NADPH-d-containing neurons are present in several sensory pathways, including olfactory, visual, auditory, and somatosensory tracts, although some nuclei in each system did not show NADPH-d activity. The wide distribution of NADPH-d activity in the pigeon CNS suggests that nitric oxide modulates sensory transmission in avian central nervous system.

Animals↗

PubMed2001

Innervation of NADPH diaphorase-containing neurons correlated with acetylcholinesterase, tyrosine hydroxylase, and neuropeptides in the pigeon cloaca.

The motility of the avian cloaca is under neural control, but little is known about the neural network that accomplishes this function. This present study was designed to determine the distribution of nitric oxide-synthesising neurons in the pigeon cloaca by enzyme histochemistry for reduced nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d). NADPH-d-positive staining was seen in the neurons and fibres in the cloaca. The highest density of nerve fibres was noted in the coprodeum and the lowest in the proctodeum. In the coprodeum, NADPH-d neurons were found singly, formed small groups of 2-10 neurons, or were seen in plexuses in the muscle layer, lamina propria, or around the arterioles. Several NADPH-d-positive neurons were also observed in the ganglia of the cloaca. NADPH-d fibres ran in the muscle layer, lamina muscularis mucosae and lamina propria, or surrounded blood vessels. The distribution pattern of acetylcholinesterase (AChE)-stained neurons and fibres in the cloaca was similar to that of NADPH-d. Double staining for NADPH-d and AChE showed colocalisation of the 2 enzymes in many neurons of the cloaca. Tyrosine hydroxylase (TH)-immunoreactive nerve fibres originating outside the cloaca were also noted. In the urodeum and proctodeum, neurons or fibres positive for NADPH-d, AChE or TH were scattered in the lamina propria. Nerve fibres immunoreactive for calcitonin-gene related peptide, galanin, methionine-enkephalin, substance P, and vasoactive intestinal peptide were found sparsely in the cloaca. Our results demonstrate that nitrergic neurons constitute a subpopulation which is closely associated with the cholinergic system in the pigeon cloaca.

Acetylcholinesterase↗

PubMed2001

Morphology of the nerve endings in laryngeal mucosa of the horse.

To discuss the significance of laryngeal sensation on various disorders of the horse, we studied the morphological and topographical characteristics of sensory structures in the laryngeal mucosa using immunohistochemistry and immunoelectron microscopy. Various sensory structures, i.e. glomerular endings, taste buds and intraepithelial free nerve endings, were found in the laryngeal mucosa by immunohistochemistry for protein gene product 9.5 (PGP 9.5) and neurofilament 200kD (NF200). Glomerular nerve endings were distributed mainly in the epiglottic mucosa; some endings were also found in the arytenoid region arising from thick nerve fibres running through the subepithelial connective tissue. Some terminals directly contacted the epithelial cells. Taste buds were distributed in the epithelium of the epiglottis and aryepiglottic fold. In the whole mount preparation, the taste buds were supplied by the terminal branching of the thick nerve fibres. In some cases, the taste buds were arranged around the opening of the duct of the epiglottic glands. The intraepithelial free nerve endings were found to be immunoreactive for substance P (SP) and calcitonin gene-related peptide (CGRP). These nerve endings were surrounded by the polygonal stratified epithelial cells in the supraglottic region, and by the ciliated cells in the subglottic region. The density of the intraepithelial free nerve endings was highest in the corniculate process of the arytenoid region and lowest in the vocal cord mucosa. The densities of CGRP- and SP-immunoreactive nerve endings in the arytenoid region were (mean +/- s.d.) 30.6+/-12.0 and 10.0+/-4.9 per unit epithelial length (1 mm), respectively and in the vocal fold mucosa, 1.1+/-0.9 and 0.8+/-0.7, respectively. Approximately one half of the CGRP immunoreactive nerve endings were immunoreactive for SP, and most SP-immunoreactive nerve endings were also immunoreactive for CGRP. Well-developed subepithelial plexus with numerous intraepithelial fibres were observed in flat or round mucosal projections that existed on the corniculate process of the arytenoid region. In conclusion, the laryngeal mucosa of the horse seems to have morphology- and/or location-dependent sensory mechanisms against various endo-and exogenious stimuli.

Animals↗

PubMed2001

Unique occurrence of the 1CF11 carbohydrate epitope in primate saliva.

We examined a large number of individual human and animal saliva samples for the reactivity with ICF11, a mouse monoclonal antibody previously produced for the characterization of human milk mucin and apparently recognizing a certain carbohydrate antigenic structure shared by various human glycoproteins in secretions. The results obtained here confirm the unique occurrence of ICF11 epitope in each and every saliva sample from humans and Old world monkeys as well, though a vast variety was observed among individual saliva samples in the immunological reactivity with ICF11.

Animals↗

PubMed2001

SEM study on the dorsal lingual surface of the lesser dog-faced fruit bat, Cynopterus brachyotis.

The dorsal lingual surface of the lesser dog-faced fruit bat was examined by scanning electron microscopy (SEM). Filiform (Fi), fungiform (Fu) and vallate papillae (V) were observed. The Fi papillae were distributed over the entire dorsal surface of the tongue. The Fi papillae notably differed in morphology by their location on the tongue and could be classified into 5 types: 1) crown-like papillae, 2) giant trifid papillae, 3) scale-like papillae, 4) small conical papillae, and 5) large conical papillae. The Fu papillae were present rounded bodies on the anterior 2/3 of the tongue. The lesser dog-faced fruit bat showed the triangular arrangement of the three V, with the apex of the triangle directed posteriorly.

Animals↗

PubMed2000

Innervation of the pigeon oviduct: correlation of NADPH diaphorase with acetylcholinesterase, tyrosine hydroxylase, and neuropeptides.

The motility of the avian oviduct is controlled by hormones and neurons, but little is microscopically known about a neural network in the oviduct. The present study was investigated to determine the distribution of nitric oxide-synthesizing neurons in the oviduct of the pigeon by histochemistry for nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d). The NADPH-d reaction was seen in the neurons and fibers. NADPH-d neurons were mainly distributed around the arterioles of the intermuscular tissue in the upper oviduct (infundibulum, magnum, and isthmus); in addition, NADPH-d neurons were also seen in the smooth muscle layers and lamina propria in the lower oviduct (uterus and vagina). NADPH-d neurons were found singly or in small groups of two-eight cell bodies. The number of NADPH-d neurons was smallest in the infundibulum, gradually increased toward the vagina. NADPH-d was also shown to be strongly positive in many neurons in the ganglia of the vaginal adventitia. Bundles of NADPH-d fibers ran in the smooth muscle layer, surrounded blood vessels, or connected with small groups of NADPH-d neurons by forming strands. Thin fibers branched from these bundles and constituted a finer network in the smooth muscle layer and lamina propria. Acetylcholinesterase staining in neurons and fibers showed a similar pattern of NADPH-d distribution in the oviduct. By double staining, 70 approximately 77% of neurons showed colocalization of NADPH-d and acetylcholinesterase in the uterus and vagina. Tyrosine hydroxylase immunoreactivity stained only nerve fibers and were distributed largely around blood vessels in the oviduct. Nerve fibers immunoreactive for calcitonin-gene related peptide, galanin, methionine-enkephalin, substance P, or vasoactive intestinal peptide were found sparsely in the oviduct. These results demonstrate that nitrergic neurons make up a large subpopulation of intrinsic neurons that are closely associated with a cholinergic system in the pigeon oviduct, thus suggesting that nitric oxide and acetylcholine could be used to modify the relaxation of the avian oviduct.

Acetylcholinesterase↗

PubMed2000

Calbindin D28k-immunoreactive afferent nerve endings in the laryngeal mucosa.

The distribution of the calbindin D28k in the laryngeal sensory structures was studied by immunohistochemistry, immunoelectronmicroscopy, and double immunofluorescence with calretinin-immunoreactivity. Moreover, origin of the nerve endings were observed using retrograde tracer, fast blue. Immunoreactivity for calbindin D28k was found in the various types of nerve endings in the larynx, namely, laminar nerve endings, nerve endings associated with the taste buds, intraepithelial nerve endings, and endocrine cells. The laminar endings with calbindin D28k-immunoreactivity were observed in the subepithelial connective tissue. In some endings, terminals were expanded. The laminar endings were also observed in the perichondrium of the epiglottic cartilage. In the epiglottic and arytenoid epithelia, thick nerve fibers with calbindin D28k-immunoreactivity ascending to taste buds and intragemmal nerve fibers were also observed. Within the epithelial layer, intraepithelial free nerve endings with calbindin D28k-immunoreactivity were observed. Furthermore, diffuse endocrine cells were observed within the laryngeal epithelium. By immunoelectron microscopy, immunoreaction products in the endings mentioned above were localized in the cytoplasm of the axon terminals and nerve fibers which contained with numerous mitochondria. Out of the 100 laminar endings, 18 endings were immunopositive for both calbindin D28k and calretinin, 33 were positive for calbindin D28k but negative for calretinin, and 49 were positive for only calretinin in the double immunofluorescence microscopy. The nerve fibers associated with the taste buds and the free nerve endings, which immunostained for calbindin D28k, were not stained with antibody against calretinin. After injection of the fast blue in the laryngeal mucosa, fast blue-labeled cells were mainly observed in the nodose ganglia. Of the total number of labeled cell in the nodose and dorsal root ganglia at the level C1 to Th2, 65.1% occurred in nodose ganglia (572/879, n = 6). In the nodose ganglia, 79.7% of labeled cells (456/572) were immunoreacted for calbindin D28k. The distribution of calbindin D28k-immunoreactivity may be differnt from that of calretinin. It is suggested that calbindin D28k have regulatory role on intracellular calcium concentration in the laryngeal sensory corpuscles.

Amidines↗

PubMed2000

Laryngeal endocrine cells: topographic distribution and adaptation to chronic hypercapnic hypoxia.

The morphology, topographic distribution, effects of denervation, and exposure to hypercapnic hypoxia of endocrine cells were examined in rat larynx. The endocrine cells, which were immunoreactive for protein gene product 9.5 (PGP 9.5) and calcitonin gene-related peptide (CGRP), were observed within the epithelial layer of the laryngeal cavity and in the laryngeal gland, while solitary endocrine cells with apical and/or basal cytoplasmic processes appeared near the glottis. After denervation of the left cervical vagosympathetic trunk and the superior laryngeal nerve, the number of mucosal endocrine cells in the denervated side was not significantly different from that in the intact side. After exposure to hypercapnic hypoxia for 3 months, the number of endocrine cells with PGP 9.5 and CGRP was markedly increased. In conclusion, the secretion of laryngeal endocrine cells may be stimulated by CO2 rather than O2. Furthermore, the endocrine cells and the sensory and autonomic nervous system may regulate each other by an axon reflex mechanism. Endocrine cells appear to play a very important role in the local regulation of the laryngeal mucosa.

Animals↗

PubMed2000

Parvalbumin in cortical epithelial cells of the pigeon thymus.

We examined the distribution of parvalbumin in the pigeon thymus by light and electron microscopic immunohistochemistry. Tissues were also examined by conventional electron microscopy to determine the ultrastructure of immunoreactive cells. Parvalbumin immunoreaction was located in epithelial cells of the cortex, which formed dense mesh-like structures. Parvalbumin-positive epithelial cells were classified into 2 types. The first comprised elongated cells. In these, the nucleus was spindle-shaped, oval, or triangular, with a slightly irregular contour and contained rich heterochromatin peripherally. The cytoplasm was pale and processes extended laterally or ramified among the surrounding thymocytes. This type of cell formed the majority of immunoreactive cells. The other cell type consisted of polygonal epithelial cells. The nucleus was oval with deep indentations. Euchromatin occupied a large part of the nucleus. The cytoplasm contained numerous cell organelles compared with the elongated type, in particular, electron-dense vacuoles of various sizes and often bundles of tonofilaments. Both types of epithelial cell were interconnected by desmosomes. No secretory granules were found in the cytoplasm of elongated or polygonal cells. These results indicate the presence of heterogeneous group of parvalbumin-immunoreactive epithelial cells and suggest the likelihood of different functional roles for parvalbumin in the pigeon thymus.

Animals↗

PubMed2000

Morphology of the glomerular nerve endings in the dorsal nasal ligament of the dog.

The nasal atrium appears to be an important sensory site in the dog, yet no literature is available concerning its nerve supply. The present paper demonstrates the occurrence of glomerular nerve endings in the canine nasal atrium, using immunohistochemistry for neurofilament protein (NFP) and for glial fibrillary acidic protein (GFAP). Glomerular nerve endings occurred on the perichondrium of the septal and the dorsal lateral nasal cartilages, and their terminal portions were attached with dense collagen fibril strands of the dorsal nasal ligament. The glomerular endings were derived from a thick parent axon which branched repeatedly. Complicated winding nerve fibers gave rise to numerous thin filamentous terminals. Accumulations of GFAP immunoreactive glial cells were also observed. Immunoelectron microscopy for NFP revealed several axon terminals in the glomerular endings which contained numerous neurofilaments and mitochondria and were incompletely covered by Schwann cell sheaths. The glomerular endings in the dog nasal vestibule are suggested to perceive tensional changes in the nasal dorsal ligament caused by the opening of the nostrils and to be involved in the reflex regulating the activity of the nasal muscles.

Animals↗

PubMed2000

Tyrosine hydroxylase- and neuropeptides-immunoreactive nerves in canine trachea.

OBJECTIVE: To determine distribution of catecholaminergic and peptidergic nerve fibers in canine tracheas by use of immunohistochemistry. SAMPLE POPULATION: 10 tracheas collected from healthy adult dogs after euthanasia. PROCEDURE: Structure of the nerve network and distribution of tyrosine hydroxylase (TH)- and 6 types of neuropeptide-containing nerves in canine tracheas were immunohistochemically studied, using neurochemical markers. RESULTS: Intraepithelial free nerve endings with immunoreactivity for calcitonin gene-related peptide (CGRP) and substance P (SP) were observed. Tyrosine hydroxylase-, SP-, vasoactive intestinal peptide (VIP)-, and galanin (GAL)-immunoreactive nerve fibers were observed within and around the submucosal seromucous gland. In the smooth muscle layer, numerous TH- and GAL-immunoreactive nerve fibers, a moderate number of VIP- and neuropeptide Y (NPY)-immunoreactive nerve fibers, and a few SP- and methionine enkephalin (ENK)-immunoreactive nerve fibers were observed. Numerous nerve cell bodies with VIP and GAL immunoreactivity and a few with SP ENK, and NPY immunoreactivity were observed. Many TH-immunoreactive fibers were arranged in a meshwork around blood vessels. Nerves with CGRP-, SP-, VIP-, GAL-, ENK-, and NPY-immunoreactivity were also observed around blood vessels. CONCLUSIONS: Complex innervation, including catecholamine- and neuropeptide-containing nerves, which may be related to regulation of muscle contraction and glandular secretion, are found in canine tracheas.

Animals↗

PubMed1999

Thymic epithelial cysts in the pigeon.

Medullary epithelial cells forming cysts in the thymus of pigeon chicks were examined in order to clarify these morphological characteristics by immunohistochemical and electron microscopic techniques. Light microscopically, cysts were divided into intracellular and intercellular types. Intracellular cysts were positive for the periodic-acid Schiff reaction, while the intercellular type was not. With immunohistochemical staining for keratin, the edges of the intercellular cysts were moderately stained, whereas the cytoplasm of epithelial cells was weakly positive. Heterophils, eosinophils and lymphocytes were included in most of the intercellular cysts. Ultrastructurally, there were two types of epithelial cells which contained intracellular cysts densely packed with microvilli. They differed with regard to the shape of the rough endoplasmic reticulum and bundles of keratin filaments, and in the presence of large vacuoles. The walls of the intercellular cysts were composed of a single type of epithelial cell with a pale nucleus and bundles of keratin filaments. Small vesicles measuring 150 to 200 nm in diameter were numerous in the apical cytoplasm beneath the microvilli. In intercellular cysts, there were abundant heterophils, eosinophils, lymphocytes and macrophages which mostly appeared to be living cells. This evidence suggests that the intercellular cysts might provide a specific microenvironment for leukocytes in the pigeon thymus.

Animals↗

PubMed1999

Ultrastructure of the thyroid gland of the one-humped camel (Camelus dromedarius).

Follicular epithelium of the thyroid gland of the one-humped camel was examined by light and electron microscopy. It consisted of a single type of epithelial cell which varied from flattened to columnar in shape. Follicular epithelial cells were characterized by the presence of markedly dilated cisternae of rough-surfaced endoplasmic reticulum, well developed Golgi apparatus, abundant small vesicles (150 nm to 200 nm in diameter) in the apical cytoplasm, and electron-dense colloid droplets measuring from 250 nm to 1600 nm. Follicular epithelial cells frequently showed apocrine secretion into colloidal lumens. Apocrine protrusions with smooth surface were dome-like or balloon-like structures and contained a fine granular matrix. These findings indicate that the morphological features of the follicular epithelial cells of the thyroid gland of the camel are essentially similar to those of mammals except for the presence of apocrine secretion, which is unique to the camel.

Animals↗

PubMed1999

Calretinin immunoreactive nerve endings in the trachea and bronchi of the rat.

Nerve endings showing calretinin immunoreactivity were examined in the lower respiratory tract of the adult rat. Tree-like nerve endings were immunostained in the tracheal and bronchial smooth muscle layer. The endings that arose from thick nerve fibers and formed corpuscles composed of many arborized nerve terminals. A few of the nerve endings were also observed in the lamina propria of the tracheal mucosa, close to the epithelial layer. Immunoelectron microscopy revealed that the immunoreactive terminals were filled with mitochondria and scattered among the intermuscular collagen fibrils. Schwann cell sheath and collagen fibrils were intercalated between the smooth muscle cells and nerve endings. The calretinin immunoreactive nerve endings observed in the present study seem to be slowly adapting stretch receptors.

Animals↗