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T Kayano

Publications and source records attributed to T Kayano.

At least 19 recordsLinked to original sources

Ossification of tracheal cartilage in aged humans: a histological and immunohistochemical analysis.

Tracheal cartilage has been considered as permanent cartilage without endochondral ossification. We examined ossification of the tracheal cartilage in 25 adults (mean age 67.8 years; range 20-87 years; male:female = 17:8). Thirteen cases (52%) demonstrated ossification of the tracheal cartilage, accompanied by the formation of lamellar bones with fatty bone marrow. Ossification was observed at the lateral peripheral region of the tracheal cartilage, while vascular invasion into the cartilage was seen even where no ossification was present. Twenty-two cases (88%) showed marked hyalinization in the central region of the tracheal cartilage. Type II collagen was immunolocalized in the cartilage matrix, except for in the central hyalinized area, while type I collagen was immunolocalized around the perichondrium and ossified areas in the tracheal cartilage. Type X collagen immunolocalized on territorial matrices around the lacunae near the ossified regions. These results suggest that tracheal cartilage in aged humans frequently ossifies physiologically, and that aging promotes osteogenesis, even in permanent cartilage.

Adult↗

Cartilage-specific matrix protein chondromodulin-I is associated with chondroid formation in salivary pleomorphic adenomas: immunohistochemical analysis.

Chondromodulin-I (ChM-I) is a novel cartilage-specific matrix protein. In the growth plates of the long bones, ChM-I was shown to be expressed in mature to upper hypertrophic chondrocytes, and to be deposited in the cartilage matrix. As ChM-I strongly inhibits angiogenesis, cartilage is avascular. Also, ChM-I has bifunctional activity against chondrocyte proliferation. On the other hand, pleomorphic adenomas of the salivary glands frequently have chondroid elements. To elucidate the relationship between chondroid formation and hypovascularity in salivary pleomorphic adenomas, we immunohistochemically examined the expression and localization of ChM-I in 35 cases of this tumor. ChM-I was immunolocalized to the lacunae in the chondroid elements of pleomorphic adenomas (100%). Type II collagen and aggrecan were immunolocalized throughout the matrix around lacuna cells of the chondroid element (100%, 91.7%), and ChM-I was infrequently immunolocalized to the spindle-shaped myoepithelial cells in the myxoid element (37.5%). Fibroblast growth factor-2 was strongly immunolocalized to the lacuna cells in the chondroid element (100%), among the neoplastic myoepithelial cells in the myxoid elements (96.9%), and on the basement membranes around the solid nests of neoplastic myoepithelial cells (71.4%). Although CD34 is a marker of endothelial cells, CD34 was expressed in the endothelial cells in only a few areas around the epithelial elements and in the fibrous element of pleomorphic adenomas. No signals for CD34 were observed in chondroid elements in pleomorphic adenomas (P < 0.001), but a few signals were seen in the myxoid elements (P < 0.05). These findings suggested that lacuna cells and neoplastic myoepithelial cells expressed ChM-I, and that this molecule may play an important role in hypovascularity and chondroid differentiation in pleomorphic adenoma. In conclusion, pleomorphic adenoma expressed ChM-I, which is involved in hypovascularity and chondroid formation in this type of tumor.

Adenoma, Pleomorphic↗

Immunohistochemical localization of members of the transforming growth factor (TGF)-beta superfamily in normal human salivary glands and pleomorphic adenomas.

Although pleomorphic adenoma is the most common type of salivary gland epithelial tumor, it frequently contains "mesenchymal"-like components, including myxoid or chondroid tissues. We reported previously that chondroid tissue formation in pleomorphic adenoma was associated with overexpression of bone morphogenetic proteins (BMPs) by neoplastic myoepithelial cells. BMPs belong to the transforming growth factor (TGF)-beta superfamily, so we hypothesized that pleomorphic adenoma may express TGF-betas and that these molecules may regulate mesenchymal-like tissue formation. To evaluate this hypothesis, we immunohistochemically examined TGF-beta1, -beta2 and -beta3 expression and localization in normal salivary glands and in 43 cases of pleomorphic adenomas. There was no evidence of TGF-beta1 expression in normal salivary glands or pleomorphic adenomas. Signals for TGF-beta2 in the normal salivary glands were observed in the intercalated ducts, while in pleomorphic adenomas they were observed in the inner ductal cells of the tubulo-glandular structures. Signals for TGF-beta3 in the normal salivary glands were observed in mucous cells, whereas in pleomorphic adenomas they were observed in the solid nests of neoplastic myoepithelial cells, in the portion showing squamous metaplasia, and in the inner ductal cells of tubulo-glandular structures. TGF-betas induce ectopic cartilage formation in vivo, but chondroid tissues in pleomorphic adenomas showed only weak TGF-beta3 expression. TGF-beta may be related to differentiation of the inner ductal cells and the neoplastic myoepithelial cells. In conclusion, pleomorphic adenomas expressed TGF-beta2 and -beta3, which may be associated with differentiation of the inner ductal cells and neoplastic myoepithelial cells.

Adenoma, Pleomorphic↗

Analysis of the antiviral activities of natural IFN-alpha preparations and their subtype compositions.

Here we report on the antiviral effects of two commercially available natural interferon-alpha (IFN-alpha) preparations, their subtype compositions, and the effects of combinations of pairs of the subtypes on virally infected cells. Our results show that the antiviral effects of these preparations depend on the target cell and on the infecting virus. The component subtypes vary with the preparations, and combinations of pairs of IFN-alpha subtypes may have synergistic or competitive effects. Our results suggest that optimal preparations of synergistically acting subtypes may provide more therapeutic benefit to patients.

Antiviral Agents↗

Expression of a gibberellin 2-oxidase gene around the shoot apex is related to phase transition in rice.

A major catabolic pathway for gibberellin (GA) is initiated by 2beta-hydroxylation, a reaction catalyzed by GA 2-oxidase. We have isolated and characterized a cDNA, designated Oryza sativa GA 2-oxidase 1 (OsGA2ox1) from rice (Oryza sativa L. cv Nipponbare) that encodes a GA 2-oxidase. The encoded protein, produced by heterologous expression in Escherichia coli, converted GA(1), GA(4), GA(9), GA(20), and GA(44) to the corresponding 2beta-hydroxylated products GA(8), GA(34), GA(51), GA(29), and GA(98), respectively. Ectopic expression of the OsGA2ox1 cDNA in transgenic rice inhibited stem elongation and the development of reproductive organs. These transgenic plants were deficient in endogenous GA(1). These results indicate that OsGA2ox1 encodes a GA 2-oxidase, which is functional not only in vitro but also in vivo. OsGA2ox1 was expressed in shoot apex and roots but not in leaves and stems. In situ hybridization analysis revealed that OsGA2ox1 mRNA was localized in a ring at the basal region of leaf primordia and young leaves. This ring-shaped expression around the shoot apex was drastically decreased after the phase transition from vegetative to reproductive growth. It was absent in the floral meristem, but it was still present in the lateral meristem that remained in the vegetative phase. These observations suggest that OsGA2ox1 controls the level of bioactive GAs in the shoot apical meristem; therefore, reduction in its expression may contribute to the early development of the inflorescence meristem.

Amino Acid Sequence↗

Proteasome-dependent degradation of cytosolic chaperonin CCT.

The chaperonin containing t-complex polypeptide 1 (CCT) is a heterooligomeric molecular chaperone that assists in the folding of actin, tubulin, and other cytosolic proteins. We show here that degradation of CCT in mammalian cells is inhibited by a proteasome-specific inhibitor, lactacystin. When CCT synthesis was inhibited by growth arrest of cells, the decrease in CCT levels was much slower in the presence of lactacystin than in its absence. Pulse-chase experiments indicated that degradation of CCT is inhibited 2- to 2.5-fold by addition of lactacystin. In addition, CCT degradation rate in ts85 cells that produce thermolabile ubiquitin-activating enzyme E1 was reduced 3-fold at the nonpermissive temperature compared to the degradation at the permissive temperature. These results indicate that the ubiquitin-proteasome system is involved in CCT degradation.

Acetylcysteine↗

Dysregulated expression of bcl-2 and bax in oral carcinomas: evidence of post-transcriptional control.

A study was conducted to investigate the gene expression of bcl-2 and bax in oral squamous cell carcinomas. We used reverse-transcriptase-polymerase chain reaction (RT-PCR) to evaluate the expression of bcl-2 and bax mRNAs and the ratio of bcl-2/bax mRNA, and employed immunohistochemistry to investigate the bcl-2- and bax-encoded proteins. It was observed that the expression level of bcl-2 mRNA or bax mRNA was not consistent with their protein level in some cases. Higher expression of bcl-2 mRNA and stronger immunostaining of bcl-2 protein were found in oral squamous cell carcinomas than in the adjacent histologically normal oral epithelium. These findings were more prominent in poorly differentiated carcinomas. No significant differences in bax mRNA and protein were observed between carcinomas and the adjacent histologically normal oral epithelium. However, poorly differentiated carcinomas showed very weak immunostaining for bax. The ratio of bcl-2/bax mRNA was higher in carcinomas than in the adjacent histologically normal oral epithelium, and higher ratios were seen in most of poorly differentiated carcinomas. This study supplies indirect evidence of post-transcriptional control of bcl-2 and bax expression, and suggests that dysregulated expression of bcl-2 and bax may be related to the differentiation of oral squamous cell carcinomas.

Adult↗

Differential diagnosis of calcium pyrophosphate dihydrate deposition of the temporomandibular joint.

Calcium pyrophosphate dihydrate (CPPD) deposition disease (pseudogout) of the temporomandibular joint (TMJ) is rare. It is characterized by the presence of crystal deposits that are birefringent under polarized light. Although these crystals are characteristically weakly birefringent, some other crystals such as those of calcium oxalate, synthetic steroids, and ethylenediaminetetraacetic acid are also birefringent. The differential diagnosis should therefore be based on a quantitative analysis of crystals or observation of the crystal structure in calcified sections. We present a case of CPPD deposition disease of the TMJ and report on the value of such an analysis to substantiate the diagnosis.

Biopsy↗

cDNA cloning and molecular analysis of papaya small GTP-binding protein, pgp1.

In the course of papaya EST collection, one clone (pRA4-3) encoding partial sequence of papaya small GTP-binding protein gene, pgp1, was obtained. Based on the sequence information of pRA4-3, the entire coding region of pgp1 was cloned using the 3'RACE PCR technique. ORF of pgp1 is 636bp long and deduced molecular weight of the protein is 23,311. Phylogenetic analysis showed that PGP1 belongs to YPT/RAB group of the small GTP-binding protein and is a homologue of RAB2. Southern analysis showed that there are several pgp1-related genes in papaya genome. Northern analysis showed that pgp1 was expressed equally in stems of seedlings that were grown under light and dark conditions. This result shows that PGP1 is not involved in the phytochrome-mediated signal transduction as an auxin signal transducer in stems of papaya seedlings.

Amino Acid Sequence↗

An inherited prion disease with a PrP P105L mutation: clinicopathologic and PrP heterogeneity.

OBJECTIVE: To clarify a clinical and neuropathologic phenotype of an inherited prion disease associated with a missense mutation at codon 105 in the prion protein (PrP) gene that was originally described as a variant of Gerstmann-Sträussler-Scheinker disease demonstrating spastic paraparesis. METHODS: Two siblings from a Japanese family are described. PrP gene analyses, neuropathologic studies with immunohistochemistry, and Western blot analysis of the PrP were performed. RESULTS: Both patients showed a missense (proline-->leucine) mutation at codon 105 and a methionine/valine polymorphism at codon 129 of the PrP gene. Clinically, Patient 1 presented with progressive spastic paraparesis, ataxia, and dementia. Patient 2, the sister of Patient 1, showed prominent action myoclonus and dementia. Neuropathologically, multiple PrP-positive amyloid plaques and diffuse PrP deposition in the deep cortical layers were found in the cerebral cortex with primarily frontal dominant atrophy in both patients. Tau-positive pathologic structures including neurofibrillary tangles, neuropil threads, and dystrophic neurites around the plaques were abundant in the brain of Patient 2. In contrast, the tau pathology was scarce in Patient 1. Western blot analysis of the brain showed different patterns of detergent-insoluble PrP fragments between the patients. CONCLUSIONS: Despite the identical codon 105 mutation and codon 129 polymorphism of the PrP gene, remarkable clinical and neuropathologic differences, and PrP heterogeneity were present between the affected siblings. The phenotypic variability might be related to PrP heterogeneity.

Amino Acid Substitution↗

Spinal cord herniation into an extensive extradural meningeal cyst: postoperative analysis of intracystic flow by phase-contrast cine MRI.

We report a patient with idiopathic spinal cord herniation who underwent postoperative myelography and phase-contrast cine magnetic resonance imaging (MRI) to clarify the condition of the ventral cystic lesion into which the spinal cord had been herniated. This 58-year-old man showed symptoms and signs compatible with Brown-Séquard syndrome. A myelogram and MRI showed that the spinal cord was incarcerated in a small space, and this finding led to the diagnosis of spinal cord herniation. In the operation, the herniated spinal cord was returned to the initial intradural space, and the dural defect was enlarged to prevent recurrence of the herniation. After the operation, leg muscle strength improved and bladder and bowel dysfunction resolved, but analgesia was unchanged. Postoperative myelography revealed a very large extradural cystic lesion, which extended from C2 to L1 vertebral level. A cerebrospinal fluid (CSF) flow study of the intradural space disclosed a near-normal pattern, but the intracystic CSF dynamics were abnormal. In the intracystic space at just the upper level of the lesion, cranial flow (reverse directional flow in comparison with the intradural flow) was seen in the systolic cycle after momentary fast caudal flow, and these CSF dynamics may have been related to the spinal cord herniation.

Brown-Sequard Syndrome↗

Expression of bone matrix proteins, osteonectin and osteopontin, in salivary pleomorphic adenomas.

Osteonectin (OSN) is a glycoprotein involved in the early steps of the mineralization of skeletal tissue, while osteopontin (OPN) is a protein involved in normal and pathological calcifications. OSN and OPN are non-collageneous bone matrix proteins expressed by some epithelial tumor cells in exceptional cases. We immunohistochemically investigated the presence and the distribution of OSN and OPN in 43 pleomorphic adenomas to elucidate the production of their molecules by modified myoepithelial cells. In normal salivary glands, OSN was immunolocalized in the striated ducts, while OPN was not expressed. In pleomorphic adenomas, the inner layer of tubulo-glandular structures and modified myoepithelial cells in the myxoid areas showed moderate positivity for OSN (83.7%). OSN was expressed in all of the lacuna cells in the chondroid areas. OPN was strongly expressed in the stroma of the myxoid and hyaline areas of the pleomorphic adenomas (65.1%), but there was no expression of OPN in the chondroid area. All cases of pleomorphic adenomas expressed type IV collagen. These findings suggested that OSN was related to the production of the type IV collagen by modified myoepithelial cells, whereas OPN was involved in the stromal formation of myxoid or hyaline tissues in pleomorphic adenomas. In summary, pleomorphic adenomas expressed the bone matrix proteins OSN and OPN.

Adenoma, Pleomorphic↗

Immunohistochemical localization of the bone morphogenetic protein-6 in salivary pleomorphic adenomas.

Salivary pleomorphic adenomas are often associated with chondroid tissue formation. We have found that bone morphogenetic proteins (BMP), especially BMP-2, may play an important role in ectopic chondrogenesis in this tumor. Bone morphogenetic protein-6 was reported to be related to the osteogenic metastasis of prostatic carcinomas. The relationship between BMP-6 expression and chondroid tissue formation is investigated. Twenty-three pleomorphic adenomas were examined immunohistochemically. The overexpression of BMP-6 was observed in 10 pleomorphic adenomas of the major salivary glands (43. 5%), and no evidence of BMP-6 expression in any of the nine pleomorphic adenomas of the palate. Bone morphogenetic protein-6 was immunolocalized in the lacuna cells of the chondroid tissue, in which type II collagen was localized. Bone morphogenetic protein-6 was expressed in inner ductal cells of the tubulo-glandular structures in the pleomorphic adenomas. This finding indicates that BMP-6 may be associated with the differentiation of inner ductal cells. Bone morphogenetic protein-6 was expressed weakly in neoplastic myoepithelial cells in the myxoid areas, which may be related to the production of extracellular matrices. Bone morphogenetic protein-6 has a role in chondroid formation, and also tubulo-glandular differentiation in pleomorphic adenomas. In conclusion, a large portion of pleomorphic adenomas of the salivary gland origin, but not of palate origin, was shown to overexpress BMP-6 protein.

Adenoma, Pleomorphic↗

Expression of bone morphogenetic proteins in salivary pleomorphic adenomas.

Salivary pleomorphic adenomas are often associated with chondroid tissue formation. We investigated the relationship between chondroid tissue formation and the expression of bone morphogenetic proteins (BMPs), which are strong inducers of ectopic bone and cartilage formation. Fifteen pleomorphic adenomas and seven normal salivary glands were examined genetically and immunohistochemically. Semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis showed that BMP-1, BMP-2, BMP-3, BMP-4, and BMP-7 mRNAs were overexpressed in 10 (66.7%), 9 (60.0%), 1 (6.7%), 8 (53.3%), and 12 (80.0%), respectively, of the 15 pleomorphic adenomas. Overexpression of BMP-2 mRNA was observed in pleomorphic adenomas. Marked chondroid formation or expression of type II collagen was frequently observed in pleomorphic adenomas that overexpressed BMP-2 mRNA. Immunohistochemically, BMP-2 was detected in modified myoepithelial cells aroud chondroid tissue and basement membranes. These results suggest that BMPs, and expecially BMP-2, have a role in chondroid formation in pleomorphic adenomas.

Adenoma, Pleomorphic↗

Evolutionary origin of two genes for chloroplast small heat shock protein of tobacco.

Two different cDNA clones for the chloroplast small heat shock protein (smHSP) were isolated from tobacco (Nicotiana tabacum cv. Petit Havana SR1). One of the cDNAs (type I) has a full-length open reading frame (ORF) of the smHSP of 26.6 kDa. By contrast, the other one (type II) contains an additional nucleotide that causes the frame shift inside a putative ORF for the smHSP. If this nucleotide is neglected, type II cDNA encodes the smHSP that is 89% identical to that encoded by type I cDNA. Southern blot and polymerase chain reaction (PCR) analyses with genomic DNA indicated that tobacco has two different smHSP genes while two ancestors of tobacco, N. sylvestris and N. tomentosiformis, have a single gene that each corresponds to one of the two genes of tobacco. It was also found that one of the tobacco genes has an ORF for the smHSP disrupted by nucleotide insertion in the same way as type II cDNA, while both ancestor genes have a functional ORF. These results suggest that the two smHSP genes of tobacco had been derived from the two ancestor species, and that one of the two genes had been disrupted by nucleotide insertion during the course of the evolution of tobacco. Northern blot and reverse transcription (RT)-PCR analyses demonstrated that both the tobacco genes are expressed upon heat stress, exhibiting different dependences on temperature.

Base Sequence↗

Immunohistochemical localization of fibroblast growth factors (FGFs) and FGF receptor-1 in human normal salivary glands and pleomorphic adenomas.

Basic and acidic fibroblast growth factors (bFGF and aFGF) are heparin-binding growth factors, and promote fibrogenesis and angiogenesis. We investigated the immunohistochemical localization of bFGFE, aFGF, and FGF receptor-1 in pleomorphic adenomas. In the normal salivary glands, bFGF was localized in the basement membranes of intercalated ducts, acini and basal cells of the excretory ducts, while aFGF was localized focally in the intercalated ductal cells and basal cells of the excretory ducts. In pleomorphic adenomas, bFGF was immunolocalized in the basement membranes around the solid nests of myoepithelial cells, around the neoplastic myoepithelial cells in the myxoid areas, and in the lacuna cells in the chondroid areas. In contrast, chondroid areas exhibited no immunoreactivity with aFGE. Positive signals for aFGF were localized in luminal cells of the tubuloglandular structures in pleomorphic adenomas. FGF receptor-1 immunolocalized in the lacuna cells and myoepithelial cells in the solid and myxoid areas. These observations suggest that bFGF and FGF receptor-1 produced by myoepithelial cells inhibited terminal differentiation and enchondral ossification in pleomorphic adenomas. These results also suggest important roles for FGFs in the formation of various structures with mesenchymal-like histology.

Adenoma, Pleomorphic↗

[Increased incidence of senile dementia in the Hansen's disease sanatoriums of Japan].

In 1973, Narita reported that the rate of demented patients above 65 years was about 2% at the sanatorium--Tama Zenshoen, which was much lower than that of the average aged people (4-5%). The reason for that was thought to be due to the acquirement of strong mind under loneliness and difficulties faced by the patients through social enforcement to live in isolation. From that report on the low percentage of dementia among the Japanese Hansen patients reemed to be widely accepted. Fifteen years later in 1988, Narita reported that the rate of demented patients above 65 years was 3.2% in males and 3.6% in females indicating still a low rate at Tama Zenshoen. In 1994, however, Narita found unexpectedly that the percentage of dementia among patients above 80 at Tama Zenshoen was higher than the average aged population. Therefore in this report, we tried to analyze the reason for this difference. In addition to Tama Zenshoen patients, we also investigated those of another Hansen disease sanatorium namely Nagashima Aiseien which has similar structural organization as Tama Zenshoen. A comparison of dementia between these two was carried out, taking patients above 65 years as the study group (Used GBS scale based on Karasawa's method). In Tama Zenshoen, the rate of patients with dementia was 18.6% in males and 31% in females. Above 80 years those were 54.4% in males and 75.9% in females. The reason for the above high rate of dementia may be probably due to the passage of long years (40 to 50 years) after the enforcement to live in isolation causing the weakening of the spirit. The patients might have got some mental support if they had offspring, but they had no way to have any under the forced contraception. On the contrary, in Nagashima Aiseisen, the percentage of patients with dementia was low, namely 3.6% in males and 9.1% in females. In those patients above 80 years, it was 2.7% in males and 6.8% in females, those were almost similar to the average normal population (6%). Such a big difference was quite surprising. The reason behind this difference, may be due to the construction of the houses for the disabled persons. Both Nagashima Aiseien and Tama Zenshoen, have small individual rooms. In Tama Zenshoen, patients are able to visit their close neighbor, only after changing their shoes or with the aid of wheel chairs, but in Nagashima Aiseien, the corridors connecting quarters allow the patients to move easily to his neighbors with bare feet or even with crawl. Therefore, in Nagashima Aiseien, the number of patients who have social contacts with their neighbors is much greater in number which make them mentally active, thus eliminating the major factors affecting dementia. We can conclude that such communication between friends and co-mates make them alert and keep the spirit in the aged.

Aged↗