Multiple Hepatic Lipoma: A Case Report of Captive Hill Mynah with Iron Storage Disease

The present case describes multiple hepatic lipomas in a common hill mynah (Gracula religiosa). A 21-year-old female captive common hill mynah died without any notable clinical symptoms. An autopsy and histopathological examinations were conducted to determine the exact cause of death. On gross observation, the liver demonstrated a yellowish white surface color and multiple nodules indicating neoplastic lesions. Histopathological assessment found that the nodules purely comprised mature adipocytes. Furthermore, the liver exhibited an excessive accumulation of iron in hepatocytes and Kupffer cells and the infiltration of chronic inflammatory cells, suggesting iron storage disease (ISD). Based on the results, the present case was diagnosed as multiple hepatic lipomas with ISD. To the authors' best knowledge, multiple hepatic lipomas accompanying ISD lesions have not been reported previously. Hence, the present case is the first case report of hepatic multiple lipomas with ISD in veterinary medicine.

Primary well differentiated hepatic liposarcoma in a meerkat (Suricata suricatta)

A 9-year-old female meerkat (Suricata suricatta) succumbed to progressive abdominal distension, anorexia, and depression. Necropsy revealed an extensively distended abdomen with ascites and markedly enlarged liver. The liver had multiple yellowish masses and displaced the thoracic cavity and abdominal organs. There was no evidence of metastatic lesions based on the gross and microscopic findings. Histologically, the liver mass was composed of locally invasive well-differentiated neoplastic adipocytes with Oil Red O-positive lipid vacuoles. Immunohistochemistry revealed positive immunoreactivity to vimentin, S-100 and negative to pancytokeratin, desmin, smooth muscle actin (SMA), ionized calcium-binding adapter molecule 1 (IBA-1). Thus, the primary well differentiated hepatic liposarcoma was diagnosed based on gross, histological and immunohistochemistry results.

Sertoli Cell Tumor (SCT) in a Captive Black Bear (Ursus americanus)

A black bear of 29-year-old (Ursus americanus) died unexpectedly in captivity without any gross lesions or clinical signs. We identified a firm, lobulated, yellowish tan, and well-circumscribed mass embedded inside the testicular tissue at the time of necropsy. The tumor sections exhibited soft necrotic and hemorrhagic areas beneath its capsule. Histologically, the tumor comprised Sertoli cells arranged in tubules and solid sheets supported by prominent fibrous connective tissues. The Sertoli cells were positive for vimentin and ER-β expression, whereas it showed negative staining for inhibin-α, cytokeratin 19, and S-100. To the best of our knowledge, this is the rare case report of testicular Sertoli cell tumor in black bear.

Uterine metastatic rhabdomyosarcoma in a scimitar-horned oryx (Oryx dammah)

A 13-year-old female scimitar-horned oryx (Oryx dammah) died after progressive anorexia, weight loss, and depression. The necropsy showed that the retroperitoneum was compressed by a large white-to-tan uterine mass and on several sections of the mass, the uterine wall was markedly thickened because of ill-defined transmural tumor tissue. Metastatic nodules were detected in the omentum, mesentery, diaphragm, and lung. The genital tract and pulmonary and abdominal nodules exhibited highly pleomorphic sarcoma. The primary and metastatic neoplastic cells showed positive results for vimentin, desmin, and sarcomeric actin, and negative results for smooth muscle actin. Uterine metastatic rhabdomyosarcoma was diagnosed on the basis of the gross, histopathology and immunohistochemistry results.

Instant single-photon Fock state tomography

Heralded single photons are prepared at a rate of approximately 100 kHz via conditional measurements on polarization-nondegenerate biphotons produced in a periodically poled potassium-titanyl phosphate crystal. The single-photon Fock state is characterized using high-frequency pulsed optical homodyne tomography with a fidelity of (57.6+/-0.1)%. The state preparation and detection rates allowed us to perform on-the-fly alignment of the apparatus based on real-time analysis of the quadrature measurement statistics.

Effect of glass phase on the dissolution of hydroxyapatite

Nano size defect formation at grain boundary during the dissolution of hydroxyapatite in water was evaluated by adding several sintering additives for sinterability enhancement. In the case of sintered pure hydroxyapatite, significant dissolution occurred after immersion in distilled water or in simulated body fluid. The dissolution initiated at the grain boundaries creating nano-size defects like small pores that afterwards grew up to micro scale by increasing immersion time. This dissolution resulted in grain separation at the surfaces and finally in fracture. The dissolution concentrated on the grains adjacent to pores rather than those in the dense region. So hydroxyapatite ceramics containing glass powders were prepared to prevent the dissolution by strengthening grain boundary. Calcium silicate and phosphate glasses were added at 0 to 10 mass% and sintered at 1200 degrees C for 2 h in air with moisture protection. Glass phase was incorporated into hydroxyapatite to act as the sintering aid followed by crystallization in order to improve the mechanical properties without reducing biocompatibility. Dissolution tests, as well as X-ray diffraction and SEM showed little decomposition of hydroxyapatite to secondary phases and the fracture toughness increased compared to pure hydroxyapatite.

Morphological and cytochemical characteristics of periodontal Ruffini ending under normal and regeneration processes

Current knowledge on the Ruffini endings, primary mechanoreceptors in the periodontal ligament is reviewed with special reference to their cytochemical features and regeneration process. Morphologically, they are characterized by extensive ramifications of expanded axonal terminals and an association with specialized Schwann cells, called lamellar or terminal Schwann cells, which are categorized, based on their histochemical properties, as non-myelin-forming Schwann cells. Following nerve injury, the periodontal Ruffini endings of the rat incisor ligament can regenerate more rapidly than Ruffini endings in other tissues. During regeneration, terminal Schwann cells associated with the periodontal Ruffini endings migrate into regions where they are never found under normal conditions. Also during regeneration, alterations in the expression level of various bioactive substances occur in both axonal and Schwann cell elements in the periodontal Ruffini endings. Neuropeptide Y, which is not detected in intact periodontal Ruffini endings, is transiently expressed in their regenerating axons. Growth-associated protein-43 (GAP-43) is expressed transiently in both axonal and Schwann cell elements during regeneration, while this protein is localized in the Schwann sheath of periodontal Ruffini endings under normal conditions. The expression of calbindin D28k and calretinin, both belonging to the buffering type of calcium-binding proteins, was delayed in periodontal Ruffini endings, compared to their morphological regeneration. As the importance of axon-Schwann cell interactions has been proposed, further investigations are needed to elucidate their molecular mechanism particularly the contribution of growth factors during the regeneration as well as development of the periodontal Ruffini endings.

The Ruffini ending as the primary mechanoreceptor in the periodontal ligament: its morphology, cytochemical features, regeneration, and development

The periodontal ligament receives a rich sensory nerve supply and contains many nociceptors and mechanoreceptors. Although its various kinds of mechanoreceptors have been reported in the past, only recently have studies revealed that the Ruffini endings--categorized as low-threshold, slowly adapting, type II mechanoreceptors--are the primary mechanoreceptors in the periodontal ligament. The periodontal Ruffini endings display dendritic ramifications with expanded terminal buttons and, furthermore, are ultrastructurally characterized by expanded axon terminals filled with many mitochondria and by an association with terminal or lamellar Schwann cells. The axon terminals of the periodontal Ruffini endings have finger-like projections called axonal spines or microspikes, which extend into the surrounding tissue to detect the deformation of collagen fibers. The functional basis of the periodontal Ruffini endings has been analyzed by histochemical techniques. Histochemically, the axon terminals are reactive for cytochrome oxidase activity, and the terminal Schwann cells have both non-specific cholinesterase and acid phosphatase activity. On the other hand, many investigations have suggested that the Ruffini endings have a high potential for neuroplasticity. For example, immunoreactivity for p75-NGFR (low-affinity nerve growth factor receptor) and GAP-43 (growth-associated protein-43), both of which play important roles in nerve regeneration/development processes, have been reported in the periodontal Ruffini endings, even in adult animals (though these proteins are usually repressed or down-regulated in mature neurons). Furthermore, in experimental studies on nerve injury to the inferior alveolar nerve, the degeneration of Ruffini endings takes place immediately after nerve injury, with regeneration beginning from 3 to 5 days later, and the distribution and terminal morphology returning to almost normal at around 14 days. During regeneration, some regenerating Ruffini endings expressed neuropeptide Y, which is rarely observed in normal animals. On the other hand, the periodontal Ruffini endings show stage-specific configurations which are closely related to tooth eruption and the addition of occlusal forces to the tooth during postnatal development, suggesting that mechanical stimuli due to tooth eruption and occlusion are a prerequisite for the differentiation and maturation of the periodontal Ruffini endings. Further investigations are needed to clarify the involvement of growth factors in the molecular mechanisms of the development and regeneration processes of the Ruffini endings.

Alteration in the expression level of calbindin D28k in the periodontal ligament of the rat molar during experimental tooth movement

The present immunohistochemical study was designed to investigate changes in the distribution and expression level of calbindin D28k in the periodontal ligament during experimental tooth movement in the rat molar to clarify the physiological role of this protein in the ligament. In normal animals, calbindin D28k-like immunoreactivity appeared sparsely in spindle-shaped cells in the alveolar half of the periodontal ligament. Electron microscopic observations showed that these immunoreactive cells were characterized by well-developed rough-surfaced endoplasmic reticulum and phagosomes--which often contained collagen fibers--suggesting that these cells could be categorized as periodontal fibroblasts. Twelve hours following the onset of the experimental tooth movement, cells positive for calbindin D28k increased in number in the periodontal ligament, especially in the alveolar half of the pressured side. Immunoelectron microscopy showed that the calbindin D28k-immunopositive cells had morphological features similar to those of fibroblasts in the normal ligament, and that these cells occasionally made contact with immunonegative macrophage-like cells. Immunopositive cells gradually decreased in number, and the distribution of the cells and intensity of the immunoreactivity returned to normal levels by 14 days following the induction of the experimental tooth movement. The present results suggest that calbindin D28k plays an important role in the homeostasis and cyto-protection of fibroblasts in the periodontal ligament at the initial phase of experimental tooth movement.

Immunohistochemical observation of growth-associated protein 43 (GAP-43) in the developing circumvallate papilla of the rat

The distribution and development of growth-associated protein 43 (GAP-43)-like immunoreactivity (-LI) in the rat circumvallate papilla (CVP) were compared to those of protein gene product 9.5 (PGP 9.5)-LI. In the adult, thick GAP-43-like immunoreactive (-IR) structures gathered densely in the subgemmal region. Some of these further penetrated the apical epithelium and trench wall epithelium. At least two types of GAP-43-IR structures were recognized; taste bud-related and non-gustatory GAP-43-IR neural elements. Immunoelectron microscopy revealed that GAP-43-LI was localized predominantly in the Schwann cells, and a few axons displayed GAP-43-LI in the lamina propria. In the trench epithelium, GAP-43-LI was detected in the cytoplasmic side of the axonal membrane. Some intragemmal GAP-43-IR axons made synaptic-like contacts with taste bud cells. At least four developmental stages were defined on the basis of the changes in distribution of GAP-43-LI. In stage I [embryonic day (E) 16-17] GAP-43-IR structures accumulated at the lamina propria just beneath the newly-formed circumvallate papilla. In stage II (E18-19) GAP-43-IR nerve fibers began to penetrate the apical epithelium. In stage III [E20-postnatal day (P) 0] GAP-43-IR nerve fibers first appeared in the trench wall epithelium. Penetration of GAP-IR nerve fibers occurred in the inner trench wall epithelium first, and then in the outer trench wall epithelium. In stage IV (P1-) the distribution of GAP-43-LI was similar to that observed in the adult; but the density of GAP-43-LI was much higher than in adults. PGP 9.5-LI showed a similar distribution pattern to that of GAP-43-LI, except for round-shaped cells in the apical epithelium at the late embryonic stages, and in taste bud cells and intralingual ganglionic cells which lacked GAP-43-LI. The similarities in distribution patterns of GAP-43-LI and PGP 9.5-LI during the development and mature circumvallate papilla suggest that GAP-43 may be a key neuronal molecule for induction and maintenance of the taste buds.

Growth-associated protein-43 (GAP-43) in the regenerating periodontal Ruffini endings of the rat incisor following injury to the inferior alveolar nerve

Alterations in the levels of growth-associated protein 43 (GAP-43)-like immunoreactivity (-LI) were examined in the lingual periodontal ligament of the rat incisor following two types of injury (resection and crush) to the inferior alveolar nerve (IAN). In normal animals, GAP-43-like immunoreactive (IR) structures were observed as tree-like ramifications in the alveolar half of the lingual periodontal ligament of incisors. Under immunoelectron microscopy, GAP-43-LI appeared in the Schwann sheaths associated with periodontal Ruffini endings; neither cell bodies of the terminal Schwann cells nor axonal profiles showed GAP-43-LI. During regeneration of the periodontal Ruffini endings following resection of the IAN, GAP-43-LI appeared in the cytoplasm of the terminal Schwann cell bodies and axoplasm of the terminals. The distribution of GAP-43-LI in the Ruffini endings returned to almost normal levels on days 28 and 56 following the injury. The changes in the distribution of GAP-43-LI following the crush injury were similar to those following resection; however, expression of GAP-43-LI was slightly higher for the entire experimental period compared with the resection. The transient expression of GAP-43 in the terminal Schwann cells and axonal profiles of the periodontal Ruffini endings following nerve injury suggests that GAP-43 is closely associated with axon-Schwann cells interactions during regeneration.

Carbonic anhydrase isozyme II immunoreactivity in the mechanoreceptive Ruffini endings of the periodontal ligament in rat incisor

The present study describes the distribution of carbonic anhydrase isozyme II (CA II) in the lingual periodontal ligament of the rat incisor. Some thick nerve fibers in the nerve bundle displayed CA II-like immunoreactivity (LI) as well as non-neuronal elements such as osteoclasts. At the alveolar half of the lingual periodontal ligament of the incisor, thick CA II-like immunoreactive (-IR) nerve fibers showed a tree-like raminification, but thin and beaded CA II-IR nerve fibers were rare. Under the electron microscope, CA II-LI were diffusely localized in the axoplasm of the axon terminals surrounded by Schwann sheaths which were immunonegative for CA II. The cell bodies of the terminal Schwann cells associated with the periodontal Ruffini endings did not exhibit CA II-LI. The present immunohistochemical evidence indicates that CA II may participate in the regulation of the intra-neuronal ion in the periodontal Ruffini endings which are thought to be in a state of high neuronal activity.

Immunocytochemical demonstration of beta 1-subunit of Na+/K(+)-ATPase in the mechanoreceptive Ruffini-like endings of the rat incisor ligament

The localization of one of the isoforms of Na+/K(+)-ATPase, the beta 1-subunit, was investigated in the periodontal Ruffini endings of rat incisors by light- and electron-microscopic immunocytochemistry. Immunoreactivity for the rat beta 1-subunit followed the pattern of dendritic terminal arborization in the alveolar half of the lingual periodontal ligament. Ultrastructurally, the reaction products were localized in dilatations of axons, possibly the terminals of Ruffini-like endings in the periodontal ligament. No immunoreactivity was seen in Schwann cells. The immunostaining results support the view that the beta 1-subunit of Na+/K(+)-ATPase is the predominant isoform in sensory neurones, and that this protein is a useful marker for periodontal Ruffini-like endings.

Calbindin D28K-like immunoreactive nerve fibres in the predentine of rat molar teeth

Immunoelectron-microscopy was applied to reveal the existence of nerve fibres and terminals showing calbindin D28k (CB)-like immunoreactivity (IR) in the rat molar tooth pulp. In the root pulp, thick, smooth-surfaced CB-IR nerve fibres were in bundles accompanying the blood vessels. In the coronal pulp, the fibres arborized repeatedly and extensively. CB-IR nerve fibres had a predominantly thick, smooth-surfaced appearance, though parts appeared thin and beaded. Occasionally some thin, varicose CB-IR nerve fibres ran along the odontoblasts, penetrating into the predentine alongside the dentinal tubules. They could be traced for approx. 10-20 microns into the predentine from the pulp-predentine border. Immunoelectron-microscopy revealed that only some of the nerve terminals in the predentine showed CB-IR, and that predentinal CB-IR nerve terminals were located close to the odontoblast processes. No synaptic structures were observed between them. The presence of CB-IR nerve terminals in the predentine suggests that many, if not all, CB-IR nerve fibres could be nociceptors. The CB could be involved in Ca2+ homeostasis during the activation of nociceptors.

Calretinin-like immunoreactivity in the Ruffini endings, slowly adapting mechanoreceptors, of the periodontal ligament of the rat incisor

The distribution and ultrastructural localization of calretinin (CR)-like immunoreactivity (-LI) were investigated in the lingual periodontal ligament of rat incisors. Some thick nerve fibers within the nerve bundle displayed CR-LI; these CR-like immunoreactive (-IR) nerve fibers entered the alveolar half of the lingual periodontal ligament of the incisor where dendritic terminal arborization was exhibited. Thin and beaded CR-IR nerve fibers were rarely observed in the periodontal ligament. Observations of adjacent sections immunostained with protein gene-product 9.5 (PGP 9.5) revealed that most, if not all, PGP 9.5-IR nerve terminals showing a dendritic arborization expressed CR-LI. Immunoelectron microscopic observations showed that electron-opaque immunoreaction products were localized in the axoplasm of the axon terminals, except for the mitochondria, which were surrounded by Schwann sheaths and multiple-layered basal lamina. Neither cell bodies, the cytoplasmic extension of terminal Schwann cells, nor other cellular elements such as periodontal fibroblasts exhibited CR-LI. The present findings suggest that Ruffini endings, an essential mechanoreceptor in the periodontal ligament and categorized as a slowly adapting mechanoreceptor, express CR-LI, and that CR may participate in the Ca2+ homeostasis against external stimuli in the periodontal Ruffini endings.

Regulations of collagen synthesis by ascorbic acid, transforming growth factor-beta and interferon-gamma in human dermal fibroblasts cultured in three-dimensional collagen gel are photoaging- and aging-independent

Decreased collagen synthesis and loss of responsiveness to growth factors are well known phenomena in in vivo or in vitro aged cells. Ascorbic acid and some cytokines such as transforming growth factor-beta and interferon-gamma are important regulators of collagen synthesis. To investigate the responsiveness of fibroblasts with regard to the photoaging and aging process, we examined the effect of ascorbic acid, TGF-beta, and IFN-gamma on collagen synthesis in dermal fibroblasts from three newborn foreskins (1 day old) and in both exposed and unexposed skin fibroblasts from 4 old individuals (60-76 years old) cultured in monolayer and in collagen gel. We demonstrated that basal levels of collagen synthesis decreased with increasing age. Photoaged fibroblasts in collagen gel showed greater basal collagen synthesis than aged fibroblasts in the same individuals, but similar basal collagen synthesis in monolayer cultures. Even though basal levels of collagen synthesis in collagen gel are downregulated in a photoaging- and aging-dependent manner, collagen synthesis by ascorbic acid in collagen gel, and by TGF-beta and IFN-gamma in both monolayer culture and collagen gel were regulated in a photoaging- and aging-independent manner. In monolayer culture, however, the responsiveness to ascorbic acid in newborn fibroblasts was greater than in photoaged and aged fibroblasts. Our results suggest that there are differences in collagen synthesis between photoaged and aged cells, depending on culture conditions. Responsiveness to ascorbic acid, TGF-beta and IFN-gamma related to collagen synthesis in photoaged and aged fibroblasts in collagen gel appears to be the same as in newborn fibroblasts, even though basal levels of collagen synthesis are downregulated in a photoaging- or aging-dependent manner.

Immunohistochemical localization of calbindin D28k in the periodontal Ruffini endings of rat incisors

It was examined whether calbindin D28k (CB) might be located in the rat incisor periodontal Ruffini ending, an essential mechanoreceptor in periodontal ligament, by light- and electron-microscopic immunohistochemistry. Some thick nerve fibers showing CB-like immunoreactivity (LI) entered the lingual half of the periodontal ligament of the incisor and showed the dendritic terminal arborization. Electron-dense immunoreaction products indicating CB-LI were distributed diffusely in axoplasm of the axon terminals, no mitochondria, however, were not labeled. Neither cell bodies nor cytoplasmic extensions of the terminal Schwann cells exhibited CB-LI. CB was presumed to be involved in the maintenance of Ca2+ homeostasis in the mechano-electric transduction in mechanoreceptors in the periodontal ligament.

Regeneration of periodontal primary afferents of the rat incisor following injury of the inferior alveolar nerve with special reference to neuropeptide Y-like immunoreactive primary afferents

Regeneration of primary afferents and the expression of neuropeptide Y (NPY) in the lingual periodontal ligament of the rat incisor were examined following different types of injury (resection or crush) of the inferior alveolar nerve (IAN) combined with superior cervical ganglionectomy. In normal animals, protein gene product 9.5 (PGP 9.5)-like immunoreactivity (-LI) was localized in the middle areas of the alveolus-related part of lingual periodontal ligament; some of these nerve fibers showed terminal ramification and morphologies resembling those of the periodontal Ruffini endings, and very few thin varicose NPY-like immunoreactive (-IR) nerve fibers were detected around the blood vessels. Three days following crush injury of the IAN, the number of PGP 9.5-IR nerve fibers decreased, then increased to the normal levels around 10-15 days following injury. NPY-IR primary afferents first appeared around 5 days following crush injury, increased in number gradually, reaching a peak around 14 days, and then decreased. No NPY-IR primary afferents were detected 56 days following crush injury of the IAN. The terminal morphology of NPY-IR primary afferents observed around 10-14 days following injury was similar to that of PGP 9.5-IR nerve fibers in the normal animals, but less expanded. The changes in distribution of PGP 9.5-IR and NPY-IR nerve fibers following resection were similar to those observed following crush injury but regeneration was slightly delayed. The present results suggest that injury-evoked NPY is closely associated with the regeneration process of mechanoreceptors in the periodontal ligament following injury of the IAN.

Congenital onychodysplasia of the index fingers--Iso-Kikuchi syndrome. A case involving the second toenail

We report a case of congenital onychodysplasia of the index fingers (Iso-Kikuchi syndrome) in a 2-year-old boy who had nail deformities on both index fingers and the left second toe. He had a micronychia of the left index fingernail, malalignment and abnormal lunula of the right index fingernail and micronychia and malalignment of the left second toenail. Congenital onychodysplasia of the index fingers (COIF) is a rare condition characterized by various forms of nail dysplasia commonly involving the index fingers, but not infrequently also the neighbouring fingers such as the middle fingers and thumbs. The five criteria characterizing COIF include the following: (i) congenital occurrence; (ii) unilateral or bilateral index finger involvement; (iii) variability in nail appearance; (iv)possible hereditary involvement; and (v) frequently associated bone abnormalities. The nails of COIF include the full spectrum of nail dysplasia, from an irregular lunula, malalignment, micronychia (hypoplastic and rudimental), polyonychia (split rudimental), and anonychia, specifically affecting the index fingers. Our patient represents various forms of nail dysplasia of the both index fingers and left second toe such as micronychia, malalignment and abnormal lunula. To our knowledge, the association with second toenail dysplasia in COIF has not previously been reported.

The effects of peripheral nerve injury of the masseteric nerve on the levels of calcium binding proteins and neuropeptide Y, and their correlation in the mesencephalic trigeminal nucleus of the rat

Combined retrograde neuronal tracing with FluoroGold (FG) and a double immunofluorescence method was performed to examine the effects of peripheral nerve injury of the masseteric nerve (MassN) on the levels of two calcium binding proteins (CaBPs), parvalbumin (PV) and calbindin D28k (CB), and neuropeptide Y (NPY) in the mesencephalic trigeminal nucleus (MesV) in the rat. In the normal MesV, many medium- to large-sized unipolar PV-like immunoreactive (-IR) cells were detected through the entire rostrocaudal extent, but CB-IR cells were rarely observed. No NPY-IR cells were observed in the normal MesV. The distributions of these three neurochemical markers in the MesV contralateral to the transection of Mass were almost identical to those observed in the normal MesV. Four days following transection and application of FG to the MassN, approximately 52% (572/1104) and 38% (414/1104) of FG-labeled cells (FG cells) in the MesV displayed PV-like immunoreactivity (-LI) and NPY-LI, respectively; Approximately 24% (265/1104) of FG cells showed both PV-LI and NPY-LI. Approximately 47% (265/572) of FG cells with PV-LI showed NPY-LI or 64% (265/414) of FG cells with NPY-LI displayed PV-LI. Fourteen days following transection and application of FG, the percentage of FG cells with PV-LI significantly decreased to 36% (365/1024) compared to that observed 4 days post-injury; approximately 44% (448/1024) of FG cells displayed NPY-LI; approximately 38% (141/365) of FG cells with PV-LI showed NPY-LI and approximately 31% (141/448) of FG cells with NPY-LI displayed PV-LI. In contrast, FG cells showing CB-LI were very rare on 4 days (1%; 15/1182) or 14 days (1%; 16/1085) following MassN transection. The present results indicate that the levels of PV in the MesV decreased 14 days following the MassN injury compared to those observed 4 days post-injury and rapid induction of NPY in the injured MesV neurons, and that the correlation between CaBP and NPY in the MesV following the MassN transection is different from that observed in the trigeminal ganglion, which is equivalent to the MesV, following peripheral nerve injury of the inferior alveolar nerve.

Protein gene-product 9.5 in developing mouse circumvallate papilla: comparison with neuron-specific enolase and calcitonin gene-related peptide

The present study was made to investigate the ontogeny of protein gene-product 9.5 (PGP 9.5)-like immunoreactivity (-LI) in the developing mouse circumvallate papilla (CVP), and its distribution was compared to that of neuron-specific enolase (NSE) and calcitonin gene-related peptide (CGRP). In adult CVP, PGP 9.5-LI was observed in the subgemmal nerve plexus; some thin PGP 9.5-like immunoreactive (-IR) nerve fibers penetrated taste buds and apical epithelium. PGP 9.5-LI was also observed in the spindle-shaped cells in taste buds, and a small number of round- or oval-shaped ganglionic cells in the lamina propria. The distribution of NSE-LI was comparable to that of PGP 9.5-LI. CGRP-LI was observed in the nerve fibers only; distribution of CGRP-IR nerve fibers was similar to that of PGP 9.5-IR nerve fibers, although the number of CGRP-IR nerve fibers was smaller than that of PGP 9.5-IR nerve fibers. At least six developmental stages were defined with regard to the developmental changes in the distribution of PGP 9.5-LI from embryonic day (E) 12 to adulthood: Stage I (E12-13)-a dense nerve plexus of PGP 9.5-IR nerve fibers was detected in the lamina propria beneath the core of newly-formed papilla. Stage II (E14-16) - thin PGP 9.5-IR nerve fibers penetrated the apical epithelium, and a few round-shaped cells in the apical epithelium also displayed PGP 9.5-LI. Stage III (E17-18) - thin PGP 9.5-IR nerve fibers penetrated the inner lateral epithelium of the trench. Stage IV [Postnatal day (P) 0-3] - many PGP 9.5-IR nerve fibers penetrated the outer lateral epithelium of the trench; later in this stage, taste buds appeared. Stage V (P5-10) - a small number of PGP 9.5-IR cells in the taste buds appeared, and their number increased gradually. Stage VI (P14-adult) - the number of PGP 9.5-IR taste cells increased and reached the adult level, while the number of PGP 9.5-IR nerve fibers decreased. The development of NSE-LI was similar to that of PGP 9.5-LI. CGRP-IR nerve fibers were detected at E12 in the lamina propria, and the development of the intraepithelial CGRP-IR nerve fibers was similar to that of PGP 9.5-IR nerve fibers. The present results indicate that invasion by nerve fibers of the epithelium of lingual papillae occurs in a complex manner, and that these nerve fibers may participate in the formation of the taste buds.

Immunoelectron microscopic study on neuropeptide Y in the periodontal ligament of the incisor following peripheral nerve injury to the inferior alveolar nerve in the rat

Immunoelectron microscopic analysis was carried out to examine whether neuropeptide Y (NPY)-like immunoreactivity (-LI) is localized in mechanoreceptors in the lingual periodontal ligament of the rat incisor following peripheral nerve injury to the inferior alveolar nerve (IAN). In the lingual periodontal ligament of normal animals, no NPY-like immunoreactive (-IR) primary afferents were observed, except for a very few sympathetic perivascular nerve fibers which showed NPY-LI. Fourteen days following chronic constriction injury to the IAN combined with sympathectomy of the superior cervical ganglion, thick NPY-IR nerve fibers showing tree-like raminifications were detected in the shear zone between the tooth-related part and alveolus-related part as well as in the alveolus-related part. Immunoelectron microscopy revealed that expanded NPY-IR nerve terminals were covered with several Schwann sheaths and that a part of the axoplasm expanded to the surrounding tissues. These ultrastructural features of NPY-IR structures were identical to those of periodontal Ruffini endings, categorized as slowly adapting mechanoreceptors. Thick (6-8 microns in diameter) NPY-IR axons were also observed without any apparent myelin sheath. The present results provide further evidence that NPY is closely associated with thick axons, probably myelinated nerves and Ruffini endings, following peripheral nerve injury.

Neuropeptide Y-like immunoreactive primary afferents in the periodontal tissues following dental injury in the rat

The distribution of neuropeptide Y (NPY)-like immunoreactive (-IR) nerve fibers in the periodontal tissues following dental injury to the rat maxillary first molar was examined with a combination of dental injury and surgical sympathectomy of the superior cervical ganglion (SCGx). In normal animals, NPY-IR nerve fibers were observed around the blood vessels of the trigeminal ganglion, dental pulp and periodontal tissues. These nerve fibers completely disappeared following SCGx. Fourteen days following dental injury of the maxillary first molar combined with SCGx, a small number NPY-IR cells was observed in the dorsal to middle portion of the maxillary division of the trigeminal ganglion. These were mostly medium- to large-sized cells with a mean +/- SD cross-sectional area of 541.4 +/- 239.3 microns 2. Approx. 50% of these cells had the cross-sectional areas between 400-600 micron 2. In the periodontal tissues of injured first molar, thick NPY-IR nerve fibers showing an irregular appearance were detected in the apical region. Immunoelectron microscopy showed that most NPY-IR nerve fibers near the lower half of the injured periodontal ligament had an axonal diameter of approx. 7-8 microns, and lacked apparent myelin sheaths. Near NPY-IR nerve fibers, many macrophages with phagosomes containing debris of the myelin sheaths were observed. At the oral epithelium covering the injured roots of the maxillary first molar, thick NPY-IR nerve fibers were recognizable and some penetrated the epithelium. No NPY-IR nerve fibers were observed in the dental pulp or periodontal tissues in second and third molars, and ultrastructural views of nerve fibers were almost intact following combined SCGx and dental injury to the first molar. The present results indicate that NPY-IR primary afferents appeared in the periodontal tissues following dental injury, and that NPY may be closely associated with the regeneration process of injured primary afferents.

Distribution and possible origin of galanin-like immunoreactive nerve fibers in the mammalian dental pulp

Human, dog, cat and rat dental pulps were investigated for the presence and distribution of galanin-like immunoreactive (-IR) nerve fibers, and the possible origin of pulpal galanin-IR nerve fibers in the rat was examined. Galanin-IR nerve fibers were present in the dental pulps of all species examined. Two types of galanin-IR nerve fibers were distinguished with regard to morphology; thin varicose nerve fibers and thick smooth-surfaced nerve fibers. Thin varicose galanin-IR nerve fibers were seen to run along the blood vessel in the human, dog and cat root pulp. In the coronal pulp, galanin-IR nerve fibers ran toward the odontoblastic layer but they did not form the subodontoblastic nerve plexus. In rat molar pulp, few galanin-IR nerve fibers were observed; the distribution of these nerve fibers was similar to those in human, dog and cat pulp. In contrast, many thick smooth-surfaced galanin-IR nerve fibers were observed near the blood vessels in incisor pulp of the rat; occasionally a few varicose galanin-IR nerve fibers were also observed. Transection of the inferior alveolar nerve or mandibular nerve caused complete disappearance of galanin-IR nerve fibers in rat dental pulp, while surgical sympathectomy of the superior cervical ganglion did not affect their distribution. The present results indicate that galanin-IR nerve fibers are present in the mammalian dental pulp, and that the intrapulpal galanin-IR nerve fibers in the rat originate from the trigeminal ganglion and are primary afferents.

Ultraviolet B irradiation-enhanced interleukin (IL)-6 production and mRNA expression are mediated by IL-1 alpha in cultured human keratinocytes

Ultraviolet (UV) B radiation may trigger cutaneous inflammatory responses by directly inducing epidermal keratinocytes to elaborate specific cytokines such as interleukin (IL-1) and IL-6. Because IL-1 is a potent inducer of IL-6, one may speculate that the release of IL-6 by keratinocytes after UV exposure is mediated via the release of IL-1 in an autocrine or paracrine manner. We demonstrated that UVB irradiation upregulated IL-1 alpha mRNA at a lower dose (15 mJ/cm2) and then downregulated IL-1 alpha mRNA expression at high doses (30-40 mJ/cm2). The kinetic profile of IL-1alpha mRNA expression showed a biphasic response, with the early increase by 1 h after UV exposure and the secondary increase at 6 h after UV. On the other hand, the expression of IL-6 mRNA was increased with increasing doses of UVB (0-45 m/J/cm2) and showed a single peak at 6 h post UV. These results may indicate that UVB radiation could regulate the expression of IL-1alpha and IL-6 mRNA in keratinocytes by different mechanisms. Our data show that anti-human IL-1alpha antibody inhibits UV-induced IL-6 production and mRNA expression in cultured keratinocytes. The addition of recombinant IL-1alpha to the medium increased IL-6 synthesis and augmented IL-6 production and mRNA expression in cultured human keratinocytes by UVB irradiation. These results support the hypothesis that UVB irradiation-enhanced IL-6 production and mRNA expression may be mediated by IL-1alpha.

Enhanced proliferation and collagen synthesis of human dermal fibroblasts in chronically photodamaged skin

Cutaneous aging can be divided into intrinsic aging and photoaging. We investigated the influence of aging and photoaging on the proliferation and collagen synthesis of human dermal fibroblasts cultured 3-dimensionally in a collagen gel. We examined 11 human dermal fibroblast cell lines cultured from 3 newborn skins (1 day old), and both exposed and unexposed skin from 4 elderly volunteers (60, 60, 73, 76 years old), respectively. Newborn fibroblasts actively proliferated within the attached collagen gels compared with the elderly cell lines. Within the attached collagen gels in the presence of 10% fetal calf serum (FCS), the fibroblasts from exposed skin proliferated rapidly compared with fibroblasts from unexposed skin from the same individuals. In collagen gel and monolayer cultures with 1% FCS, the percentage of collagen synthesized by photoaged and aged fibroblasts decreased significantly compared with that by newborn fibroblasts. When the fibroblasts were cultured three dimensionally in attached collagen gels in the presence of 1% FCS, the relative levels of collagen synthesis by cultured fibroblasts from photoaged skin were increased significantly compared with those of aged skin fibroblasts from the same individuals. These results suggest that fibroblasts of exposed skin may be more active than those of unexposed skin and that the three-dimensional culture of fibroblast can be used as a model to investigate the influence of aging and photoaging on cell functions.

Neuropeptide Y-immunoreactive primary afferents in the dental pulp and periodontal ligament following nerve injury to the inferior alveolar nerve in the rat

The distribution of neuropeptide Y (NPY)-immunoreactive (IR) primary afferents in the dental pulp and periodontal ligament of the rat mandible were examined following combined chronic constriction injury (CCI) of the inferior alveolar nerve (IAN) and sympathectomy of the superior cervical ganglion (SCG). NPY-IR nerve fibers were observed around the blood vessels in the trigeminal ganglion, dental pulp and periodontal ligament in normal animals. Following combined CCI of the IAN and sympathectomy of SCG (SCGx), perivascular NPY-IR nerve fibers originating from SCG disappeared completely, but many NPY-IR nerve fibers coming from the trigeminal ganglion appeared in the dental pulp and periodontal ligament. In the molar dental pulp, thick NPY-IR nerve fibers were observed within the nerve bundle, and some thin NPY-IR nerve fibers ran towards the odontoblast layer; very few NPY-IR nerve fibers were observed in the incisor pulp. In the periodontal ligament of molar, thick NPY-IR nerve fibers appeared at the alveolar part following combined CCI of IAN and SCGx. In the lingual portion of the periodontal ligament of the incisor, many thick NPY-IR nerve fibers were observed. These occasionally showed a tree-like appearance, resembling immature Ruffini endings; slowly adapting mechanoreceptors. The present results indicate that periodontal mechanoreceptors are among the main targets of injury-evoked NPY following IAN injury.

Partial coexistence of neuropeptide Y and calbindin D28k in the trigeminal ganglion following peripheral axotomy of the inferior alveolar nerve in the rat

Immunohistochemistry was applied to examine the correlation between neuropeptide Y (NPY) and the two calcium binding proteins (CaBPs) parvalbumin (PV) and calbindin D28k (CB) in the trigeminal ganglion following peripheral axotomy of the inferior alveolar nerve (IAN) in the rat. Five days following transection and application of FluoroGold (FG) to the cut end of the IAN, approximately 14.8% (80/539) and 18.6% (90/483) of FG-labeled IAN neurons in the trigeminal ganglion showed PV-like immunoreactivity (-LI) and CB-LI, respectively. The mean +/- S.D. area of FG-labeled PV-like immunoreactive (-IR) cells (FG/PV-IR cells) and FG/CB-IR cells were 835.9 +/- 303.1 mu m2 and 712.7 +/- 246.0 mu m2, respectively. FG/PV-IR cells were significantly larger than FG/CB-IR cells. Fourteen days following peripheral axotomy of the IAN, NPY-LI appeared in the medium- to large-sized cells. Double immunostaining revealed that approximately 3.3% (52/1569) of NPY-IR cells in the axotomized trigeminal ganglion displayed PV-LI, while approximately 26.7% (371/1392) of NPY-IR cells displayed CB-LI. The mean +/- S.D. cross-sectional areas of PV-IR and CB-IR trigeminal ganglion cells displaying NPY-LI were 819.5 +/- 265.6 mu m2 and 766.5 +/- 279.7 mu m2, respectively. There were no significant differences in the cross-sectional areas either between NPY/PV-IR cells and NPY/CB-IR cells, or between FG/PV-IR cells and NPY/PV-IR cells, or between FG/CB-IR cells and NPY/CB-IR cells. The present results indicate that injury-evoked medium- to large-sized NPY neurons were a different population from large-sized PV neurons, and NPY was partly co-localized with CB.

Substituent effects on the binding constants of arsenical-dithiol adducts

Proton nuclear magnetic resonance spectroscopy (1H NMR) was used to determine the relative binding constants for several arsenical-dithiol adducts. The compounds investigated were 2,3-dimercaptopropanol (British anti-lewisite; BAL), 1,2-ethane dithiol (ET), and 1,2-propane dithiol (PDT). It was found that PDT has a significantly higher affinity than ET or BAL for phenyldichloroarsine (PDA) in methanol.