Reactions of periodontal ligament epithelial cell clusters and OX6-immunopositive cells to experimental tooth movement and periodontitis.

BACKGROUND AND OBJECTIVE: The aim of this study was to investigate reactions of periodontal ligament epithelial cell clusters and major histocompatibility complex class II (OX6)-immunopositive cells to simultaneously induced tooth movement and periodontitis employing Waldo's method. MATERIAL AND METHODS: Elastic gums were inserted between the right upper first and second molars of rats. Animals were killed by intracardiac perfusion on days 1, 3, 7 and 14 after the experimental procedures, and maxillary molars were decalcified and processed for OCT compound. Cytokeratin and OX6 antibodies to detect epithelial and immunocompetent cells were used for double-fluorescence immunohistochemistry. Immunostained sections of rat upper molar regions were examined with a fluorescence microscope. RESULTS: Large periodontal ligament epithelial cell clusters appeared and became contiguous with each other, and OX6-immunopositive cells surrounded the clusters over time in the periodontal ligament near the gum insertion site. In the periodontal ligament distant from the gum insertion site, epithelial cell clusters and OX6-immunopositive cells were scattered. After 14 d, thickened epithelium and elongated rete pegs were found close to large epithelial cell clusters in the periodontal ligament near the gum insertion site. CONCLUSION: These findings suggest proliferation and/or aggregation of periodontal ligament epithelial cells, and interaction between OX6-immunopositive cells and the periodontal ligament epithelial cells, in response to tooth movement and periodontal inflammation. This method may be a useful experimental model to elucidate the relationship between rete pegs and periodontal ligament epithelial cell clusters in inflammatory conditions.

[Modified Hardinge approach with limited incision]. / Modifizierter Hardinge-Zugang mit Kurzinzision.

BACKGROUND: The technique of a minimally invasive anterolateral, intracapsular, modified Hardinge approach with transosseous refixation developed by the senior author is described in detail. MATERIAL AND METHODS: Clinical and radiographic data after cemented total hip arthroplasty reveal adequate outcome without increased complication rates despite limited incision technique (average 10 cm). This technique can be safely applied by surgeons in training and performed in acceptable operating times. RESULTS: A comparison of the described technique to a standard incision cannot be made from our data, but current literature suggests the main benefit to be cosmetic. A technically well performed operation with adequate long-term outcome remains far more important than a short incision.

Selective inhibition of human cytochrome P450 3A4 by N-[2(R)-hydroxy-1(S)-indanyl]-5-[2(S)-(1, 1-dimethylethylaminocarbonyl)-4-[(furo[2, 3-b]pyridin-5-yl)methyl]piperazin-1-yl]-4(S)-hydroxy-2(R)-phenylmethy lpentanamide and P-glycoprotein by valspodar in gene transfectant systems.

Our previous report showed that L754.394 and valspodar (PSC833) are potent inhibitors of midazolam hydroxylation in human jejunum microsomes and vectorial transport of vinblastine in Caco-2 cells, respectively. In the present study, to directly examine the interactions of these compounds as well as other substrates with CYP3A4 and P-glycoprotein (P-gp), we performed in vitro inhibition studies using recombinant CYP3A4-expressed microsomes and an MDR1-transfected cell line, LLC-MDR1, respectively. In CYP3A4-expressed microsomes, both L754.394 and ketoconazole, at a concentration less than 0.5 microM, are the most potent inhibitors of the formation of 1'-hydroxymidazolam, a major metabolite of midazolam formed by CYP3A4. The greatest inhibitory effect on the transcellular transport of digoxin in LLC-MDR1 cells was observed in the presence of valspodar (<0.1 microM), followed by verapamil. From a comparison of the IC(50) values, it was shown that L754.394 and valspodar exhibited the highest selectivity for CYP3A4 and P-gp, respectively. To demonstrate such specificity, both midazolam hydroxylation and digoxin transport were observed in CYP3A4 transfected Caco-2 cells, which coexpress both P-gp and CYP3A4, in the presence or absence of L754.394 (0.5 microM) and valspodar (1.0 microM). L754.394 almost completely inhibited midazolam hydroxylation, but not digoxin transport, whereas almost complete inhibition of digoxin transport was observed in the presence of valspodar, but inhibition of the hydroxylation was minimal. Thus, the present study has demonstrated that L754.394 has a specific inhibitory effect on CYP3A4, whereas valspodar is specific for P-gp.

Ultrastructural study of the relationship between the morphogenesis of filiform papillae and the keratinisation of the lingual epithelium in the rat.

Tongues were removed from rat fetuses on d 16 of gestation (E16) and from newborn (P0) and juvenile rats on d 7 (P7) and d 21 (P21) postnatally for examination by light and transmission electron microscopy. In the fetuses at E16, no rudiments of filiform papillae were visible on the dorsal surface of the tongue. No evidence of keratinisation could be recognised over the entire dorsal lingual epithelium. At P0, rudiments of filiform papillae showed a similar distribution to that seen in the adult, but had a more rounded appearance. The columnar structure of cells in the epithelium, with the different degrees of keratinisation as observed in the mature adult, was indistinct, but a keratinised layer was clearly located at the tip of each filiform papilla. In juveniles at P7, the filiform papillae on the anterior part of the tongue were long and slender, and the anterior and posterior cell columns of the filiform papillae and the interpapillary cell columns were clearly distinguishable. In juveniles at P21, the structure of filiform papillae was identical to that in the adult. These results indicate that, in rats, the morphogenesis of filiform papillae advances in parallel with keratinisation of the lingual epithelium from just before birth to a few weeks after birth.

Radioautographic studies on radiosulfate incorporation in the digestive organs of mice.

The sulfate uptake and accumulation in mouse digestive organs were studied by light microscopic radioautography. Two litters of normal ddY mice 30 days after birth, each consisting of 3 animals, were studied. One litter of animals were sacrificed 30 min after the intraperitoneal injections with phosphate buffered Na2(35)SO4, and the other litter animals were sacrificed 12 hr after the injections. Then several digestive organs, the parotid gland, the submandibular gland, the sublingual gland, antrum and fundus of the stomach, the duodenum, the jejunum, the ileum, the caecum, the ascending colon and the descending colon were taken out. The tissues were fixed, dehydrated, embedded in epoxy resin, sectioned, picked up onto glass slides, coated with radioautographic emulsion by a dipping method. AFter the exposure, they were developed, stained with toluidine blue and analyzed by light microscopy. As the results, many silver grains were observed on serous cells of the salivary glands, mucosa and submucosa of the stomach, villous cells and crypt cells of the small intestines and whole mucosa of the large intestines at 30 min after the injection. Then at 12 hr after the injection silver grains were observed on mucous cells of the salivary glands, some of the stomach glands, and mucigen granules of goblet cells in the small intestines and the large intestines. The numbers of silver grains observed in respective organs at 30 min were less than those at 12 hr. From these results, it is concluded that glycoprotein synthesis was demonstrated in several digestive organs by radiosulfate incorporation. In the salivary glands the silver grains were more observed in serous cells at 30 min, while in mucous cells more at 12 hr than 30 min after the injection. In other organs the silver grains were more at 30 min than at 12 hr. These results show the time difference of glycoprotein synthesis in respective organs.

Permeability characteristics of tetragastrins across intestinal membranes using the Caco-2 monolayer system: comparison between acylation and application of protease inhibitors.

PURPOSE: Three types of acyl tetragastrin (TG), acetyl-TG (C2-TG), butyryl-TG (C4-TG) and caproyl-TG (C6-TG) were synthesized and their in vitro intestinal permeability characteristics were examined using Caco-2 monolayers. METHODS: The disappearance of acyl-TGs from the apical side of Caco-2 monolayers was estimated by analyzing degradation and permeation processes in terms of clearance. RESULTS: The amount of native TG transported to the basolateral side was very low due to its large degradation clearance (CLd) on the apical side. Degradation of TG was reduced by chemical modification with fatty acids, which resulted in an increase in the transport of TG across Caco-2 monolayers. In addition, the permeation clearance (CLp) value of carboxyfluorescein (CF), a paracellular transport and undegradable marker, was increased in the presence of acyl-TGs. Furthermore, we investigated the effects of the protease inhibitors bacitracin and gabexate on the transport of TG across Caco-2 monolayers. In the presence of a low concentration (0.1 mM) of protease inhibitor, the CLd value of TG was reduced, but they did not affect its CLp value. However, a higher concentration (1.0 mM) of bacitracin significantly reduced TG degradation on the apical side, and further increased its CLp value. CONCLUSIONS: We demonstrated that acylation of TG made it resistant to intestinal proteases and caused it to enhance absorption of drugs, including itself, across Caco-2 monolayers. Further, bacitracin acted as both a protease inhibitor and an absorption enhancer.

Age-related effects of heat stress on protective enzymes for peroxides and microsomal monooxygenase in rat liver.

To evaluate the age-related response of essential cell functions against peroxidative damage in hyperthermia, we studied the biochemical response to heat stress in both young and aged rats. Passive hyperthermia was immediately observed in rats after exposure to hot environments. In aged rats, the rectal temperature maintained thermal homeostasis and increased to the same degree as in young rats. In these aged animals, the damage from heat stress was more serious than in young animals. In aged rats under normal environmental conditions, hepatic cytosolic glutathione peroxidase (GSH peroxidase) activities were markedly higher than those activities in younger rats. Hepatic cytosolic GSH peroxidase activities were induced by heat stress in young rats but were decreased by hot environments in aged rats. Hepatic catalase activities in young rats were not affected by hot environments, whereas in aged rats, hepatic catalase activities were seriously decreased. Catalase activities in the kidney of aged rats were also reduced by hot environments. Lipid peroxidation in the liver was markedly induced in both young and aged rats. Because the protective enzymes for oxygen radicals in aged rats were decreased by hot environments, lipid peroxidation in the liver was highly induced. In aged rats, lipid peroxidation in intracellular structures such as mitochondria and microsomes was also markedly induced by hot environments. In both young and aged rats, hyperthermia greatly increased the development of hypertrophy and vacuolated degeneration in hepatic cells. In aged rats, both mitochondria and endoplasmic reticulum of the hepatic cells showed serious distortion in shape as a result of exposures to hot environments. Microsomal electron transport systems, such as cytochrome P450 monooxygenase activities, were seriously decreased by heat stress in aged rats but not in young rats. Although the mitochondrial electron transport systems were not affected by acute heat stress in young rats, their activities were simultaneously inhibited after long-lasting heat exposure. In isolated hepatic cells and polymorphonuclear leukocytes in animals, the 70-kDa heat shock-induced proteins were markedly increased by heat stress. In conclusion, the heat stress-inducible oxygen radical damage becomes more severe according to the age of rats. Because aging and hyperthermia have a synergistic effect on lipid peroxidation, protective enzyme activities for oxygen radicals may be essential for surviving and recovering from thermal injury in aged animals and also in humans.

Study by scanning electron microscopy of the morphogenesis of three types of lingual papilla in the rat.

BACKGROUND: Many mammals have four different types of lingual papilla, namely filiform, fungiform, circumvallate, and foliate papillae, on the dorsal or lateral surface of the tongue. However, details of the morphogenesis of these lingual papillae have not been reported. We have investigated the changes in the three-dimensional ultrastructure that occur during the morphogenesis of filiform, fungiform, and circumvallate papillae in rats during fetal and postnatal development. METHODS: Tongues were removed from rat fetuses on days 12 (E12) and 16 (E16) of gestation from newborns (P0) and from juveniles on days 7 (P7) and 14 (P14), and 21 (P21) after birth. Scanning electron microscopy was used for all observations. RESULTS: In fetuses at E12, the rudiments of fungiform papillae could be observed as two rows of bulges that extended bilaterally and parallel to the median sulcus on the anterior half of the dorsal surface of the tongue. In fetuses at E16, the arrangement of the rudiments of fungiform papillae was relatively regular, with a latticelike pattern. At this stage, the outline of the rudiment of the circumvallate papilla could be recognized on the median line between the lingual body and the lingual radix. No rudiments of filiform papillae were visible. At P0, rudiments of filiform papillae were compactly distributed over the dorsal surface in the same way as in the adult. The width of these rudiments was about one-fourth that of fungiform papillae, and their tips were round as compared with those of filiform papillae in the adult. The fungiform and circumvallate papillae were large, and their outlines were somewhat irregular, as in the adult. In juveniles at P7, filiform papillae were long and slender. On the intermolar eminence, filiform papillar structures were quite large. A taste pore was clearly visible at the center of each fungiform papilla at this stage. The shape of the circumvallate papilla was similar to that in the adult. In juveniles at P14 and P21, the shapes of all three types of papilla were almost same as those in the adult. CONCLUSIONS: The rudiments of each of the three different kinds of lingual papilla appeared at a different respective stage of development in rats. The rudiments of the fungiform and circumvallate papillae, which are related to the sense of taste, were visible earlier than those of the filiform papillae, which are not involved in this sense.

Dendritic cells: a novel cellular component of the rat incisor enamel organ appearing in the late stages of enamel maturation.

Immunocompetent cells in the enamel organ of rat incisors were examined immunohistochemically using OX6, ED1, and ED2 monoclonal antibodies known to recognize the Class II MHC molecules, a monocyte-macrophage lineage, and residential macrophages, respectively. The OX6 immunopositive cells (MHC cells) were located exclusively in the enamel maturation zone. MHC cells increased in number in the incisal direction and occasionally extended cytoplasmic processes deep into the ameloblast layer. Migration of MHC cells in the ameloblast layer were also encountered. MHC cells lacked phagolysosomes and could be distinguished from typical macrophages. ED2 immunopositive cells were not seen in the enamel organ. ED1 positive cells displayed identical localization to MHC cells except that some appeared in the transitional zone. MHC cells could not be seen in the enamel organ of rat molar tooth germs. Our data confirmed the presence of a large population of "dendritic" immunocompetent cells in the enamel organ of rat incisors and characterized the ultrastructural features of these cells. Biological significance of the immunocompetent cells in the enamel organ during amelogenesis needs to be clarified.

Three-dimensional ultrastructure of the surface of the tongue of the rat snake, Elaphe climacophora.

BACKGROUND: Many studies have been performed to clarify the relationship between behavioral performance of the tongue and Jacobson's organ. The purpose of the present study was to examine the ultrastructural features of the surface of the tongue of the rat snake, Elaphe climacophora, and to delineate the functional relationship between the tongue and Jacobson's organ from a morphological perspective. METHODS: The three-dimensional ultrastructure of the surface of the tongue of the rat snake Elaphe climacophora was investigated by scanning electron microscopy. RESULTS: Most of the surface of the bifurcated apex of the tongue was relatively smooth. Dome-shaped, hemispherical bulges or microfacets were compactly arranged on the epithelial cell surface over this entire region. Intercellular borders were clearly recognizable as striations. These features were almost the same as those of the dorsal surface of the transitional area between the bifurcated lingual apex and the anterior part of the lingual body. In the posterior half of the lingual body, no microfacets were seen at all. Both microridges and microvilli were compactly distributed on cell surfaces. CONCLUSIONS: No evidence was obtained from our ultrastructural analysis for an important role of the lingual apex in the vomeronasal system. By contrast, the epithelial surface of the body of the tongue appeared suitable for retaining stimulating compounds.

Study by scanning electron microscopy of the morphogenesis of three types of lingual papilla in the mouse.

Tongues were removed from fetuses of mice on the 15th day of gestation (E15), from newborns (P0), from juveniles on the 7th day (P7) and on the 14th day (P14) after birth for examination by scanning electron microscopy. In the fetuses at E15, rudiments of fungiform papillae with a relatively regular, lattice-like pattern were visible on the anterior half of the dorsal surface of the tongue. The outline of the rudiment of a circumvallate papilla could be recognized on the median line between the lingual body and the lingual radix. No rudiments of filiform papillae could be seen. At P0, rudiments of filiform papillae were compactly distributed over the dorsal surface, as are the filiform papillae in the adult, their width was approximately one-third of that of fungiform papillae, and their tips were rounded than those of the filiform papillae in the adult. The fungiform papillae then increased in size and became somewhat irregular in shape. In juveniles at P7, the filiform papillae were long and slender, being relatively large on the intermolar eminence. A taste pore was visible in the center of each fungiform papilla at this stage. The shape of the circumvallate papilla was similar to that in the adult. In juveniles at P14, the shapes of all three types of papilla were almost the same as those in the adult. The rudiments of each of the three kinds of lingual papilla appeared at a different stage of development of mice; rudiments of the fungiform and circumvallate papillae, which are related to the sense of taste, were formed earlier than those of the filiform papillae, which are not involved in taste.

Segregated localization of immunocompetent cells and osteoclasts in the periodontal ligament of the rat molar.

The spatial distribution of dendritic cells, macrophages, and their respective precursor cells in the periodontal ligament of rat molars was examined by means of ACPase enzyme histochemistry and immunohistochemistry. Intense reactions for ACPase were localized in both the multinucleated-and mononucleated cells of the periodontal ligament located exclusively in the portions of physiological bone resorption due to the physiological migration of the molar teeth. Immunohistochemical staining with OX6-monoclonal antibody that recognizes antigen-presenting cells such as dendritic cells and macrophages revealed the localization of immunopositive cells predominantly in the portions of the periodontal ligament that showed only trace reactions for ACPase. On the other hand, a large number of ED1-immunopositive cells, comprising a broad spectrum of cells of monocyte origin including dendritic cells and osteoclasts, displayed an almost even distribution throughout the periodontal ligament. Our current study is the first to show clear-cut in vivo morphological evidence that the cells of the bone-resorbing, osteoclastic cell lineage and those of the non-bone resorbing, macrophagic and/or dendritic cell lineages are exclusively localized in roughly the distal and proximal regions of the periodontal ligament of rat molars, respectively. An advantage is proposed for the use of the rat molar periodontal ligament as an in vivo model system for pursuing differentiation pathways of cells of the monocyte lineage, particularly of the osteoclastic cells.

Responses of immunocompetent cells to cavity preparation in rat molars: an immunohistochemical study using OX6-monoclonal antibody.

Responses of immunocompetent cells, especially class II major histocompatibility complex (MHC) antigen-expressing cells, were investigated after cavity preparation in the erupted upper first molar teeth of rats, by immunohistochemistry using OX6-monoclonal antibody. In control teeth, OX6-immunopositive cells were predominantly located beneath the odontoblast layer in the dental pulp. Cavity preparation caused an acute edematous reaction between the injured odontoblasts and predentin, and most of OX6-immunopositive cells in the affected site shifted away from the pulp-dentin border. After 12-24 hours, many OX6-immunopositive cells accumulated along the pulp-dentin border and extended their cytoplasmic processes into the exposed dentinal tubules. After 72 hours, newly differentiated odontoblasts replaced the degenerated odontoblasts, and few OX6-immunopositive cells remained along the pulp-dentin border. Our data suggest that some of the class II MHC antigen-expressing cells in the dental pulp participate in the initial defense reaction and presumably serve as a biological sensor for the external stimuli arriving through the exposed dentinal tubules.

Immunohistochemical characterization and localization of MHC class II antigen-presenting cells in the periodontal ligament of rat incisors.

Dendritic cells have been identified both in lymphoid and nonlymphoid tissues as non-phagocytic antigen-presenting cells, equipped with extensive flamelike cytoplasmic projections. Our immunohistochemical study revealed presence of a large population of dendritic cells and other immunocompetent cells, showing a region-specific distribution, in the lingual periodontal ligament of continuously erupting rat incisors. This study aims to reveal the kinetics and cytological characterization of immunocompetent cells in the periodontal ligament of rat incisors with special reference to their differentiation pathway in the unique local environment.

The relationship between odontoblasts and immunocompetent cells during dentinogenesis in rat incisors: an immunohistochemical study using OX6-monoclonal antibody.

The relationship between odontoblasts and class II major histocompatibility complex (MHC) antigen-expressing cells in the process of dentinogenesis was studied in rat lower incisors, employing immunohistochemistry using OX6-monoclonal antibody. The dental pulp contained numerous OX6-immunopositive cells that varied in morphology from dendritic to spindle under physiological conditions. Under the electron microscope, these immunopositive cells shared common cytoplasmic features, i.e., multivesicular bodies and characteristic fine tubulovesicular structures in their cytoplasm. At the early stage of dentinogenesis, OX6-immunopositive cells, presumably of the immature type, were located in the subodontoblastic layer. During active dentin formation, the OX6-immunopositive cells increased in number and appeared in the odontoblast layer, associating intimately with fenestrated capillaries situated close to the predentin. These cells showed a dendritic appearance and possessed various sizes of multivesicular bodies and characteristic fine tubulovesicular structures, but never contained typical phagosomes. On the other hand, immunopositive macrophages characterized by typical phagosomes tended to occupy the central portion of the pulp. The results suggest that most, if not all, OX6-immunopositive cells situated deep in the odontoblast layer are dendritic cells playing a role in the defense system of the dental pulp against antigenic molecules arriving from the circulation via the fenestrated capillaries. The increasing number of OX6-immunopositive or immunonegative macrophages appearing near the incisal end of the tooth is thought to be involved in the elimination of degenerated odontoblasts.

[Invasion of esophageal cancer to neighboring structures: diagnosis by CT, conventional MR imaging and cine-MR imaging].

Seventy-four esophageal cancer patients were examined by magnetic resonance (MR) imaging and CT to evaluate invasion to the aorta and tracheobronchial tree. Aortic invasion was evaluated by axial section on MR and CT. A contact angle of less than 60 degrees indicated that the cancer had not invaded to the wall of the aorta (A2 or under). When the contact angle was 60 degrees or greater and irregularity of the contact plane was noted, aortic invasion was considered positive (A3). With this criterion, the accuracy rates of MR and CT were 84% and 78%, respectively. For evaluation of the invasion of esophageal cancer to the aorta, 39 cases were examined by cine-MR imaging. Gradient echo pulse sequence was used. When a low intensity stripe was recognized between the tumor and the wall of the aorta, this was interpreted as a negative finding of direct tumor invasion. Using this criterion, 36 of 39 cases (92%) of esophageal cancer invading to the aortic wall were correctly diagnosed. Tracheobronchial invasion was evaluated according to the deformities of the trachea and bronchi by contiguous cancers. The accuracy rates of MR and CT with this criterion were 96% and 95%, respectively. MR imaging is a useful and reliable means for the evaluation of esophageal cancer invading to the neighboring structures.

[Histopathological changes induced by thermal exposure in the rat liver].

To clarify the effects of a thermal environment on rats, histopathological changes, and temperatures in the rectum and eyes of Fischer strain rats exposed to a thermal environment of 32 degrees C for 2 days or 7 days were investigated. Thermal exposure to 32 degrees C induced elevations in rectal and ocular temperatures. The increased temperature levels persisted during the thermal exposure. Vacuolar degeneration surrounding the hepatic vein was observed in rat livers exposed to 32 degrees C for 7 days. No abnormalities were observed in other organs. These results indicate that thermal exposure to 32 degrees C induces vacuolar degeneration in hepatocytes due to the elevation of body temperature.

Histochemical demonstration of acid phosphatase activity in terminal Schwann cells associated with Ruffini endings in the periodontal ligament of rat incisors.

Histochemical staining for acid phosphatase, a marker for lysosomal elements, distinguished rounded, intensely reactive cells from less reactive fibroblasts and osteoblasts in the lingual periodontal ligament. The highly reactive cells were located exclusively in the alveolar half of the ligament. Double staining for acid phosphatase and S-100 protein confirmed that these reactive cells were identical with the terminal Schwann cells associated with periodontal Ruffini endings. Electron microscopically, reaction products for acid phosphatase were observed in the lysosomes and Golgi apparatus in the paranuclear cytoplasm of the terminal Schwann cells. As the terminal Schwann cells associated with the Ruffini endings are assumed to be capable of synthesizing exportable proteins, acid phosphatase in this type of cell may be involved in the processing of macromolecules in synthetic and/or secretory pathways.

Histochemical localization and X-ray microanalysis of calcium in the rat submandibular gland: demonstration of possible sites for microlith induction.

Rapidly frozen and freeze-substituted submandibular glands of young female rats were embedded in Epon and processed for histochemical demonstration of calcium with the glyoxal bis (2-hydroxyanil) (GBHA) staining method. GBHA staining of thick Epon sections revealed discrete calcium reactions of moderate intensity in practically every secretory granule but not in other compartments of the acinar cells. The saliva in the excretory duct was also reactive with GBHA and showed a drastic decrease in staining intensity toward the distal segments of excretory ducts with larger diameters. In addition, the duct saliva contained numerous tiny particles that were highly GBHA reactive. Stromal cells and cells lining the excretory duct were totally free of reactions. In the acinar cells, X-ray analysis detected distinct peaks for calcium in secretory granules and smaller ones in the Golgi apparatus, while they were undetectable in the rough surfaced endoplasmic reticulum (RER), implicating post-RER calcium loading in the secretory pathway. Electron-dense deposits in the duct saliva showed distinct peaks both for calcium and phosphorus, though these appeared in the acinar secretory granules and other cytoplasmic regions lacked phosphorus. Our observations thus demonstrated physiological calcium in the intra- as well as extracellular compartments of the submandibular gland, and further confirmed drastic changes in chemical composition along the synthetic and secretory pathways of the saliva, by both histochemical and X-ray microanalytical methods. GBHA staining of calcium combined with X-ray microanalysis is useful for an evaluation of the physiology and histo-pathological changes of the salivary glands associated with initial phases of microliths as well as sialoliths formation.

[Evaluation of the invasion of esophageal cancer to the aorta by cine-MR imaging].

We examined the usefulness of cine-MR imaging for evaluation of the invasion of esophageal cancer to the aorta in 12 cases. We used the technique of field echo pulse sequence. When the low intensity stripe was recognized between the tumor and the wall of aorta, we interpreted it as negative finding of the direct tumor invasion. By using this criteria, 11 of the 12 cases (92%) of the esophageal cancer for aortic wall invasion were correctly diagnosed as compared with 75% correct diagnosis by conventional MR imaging.