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T Tanabe

Publications and source records attributed to T Tanabe.

At least 217 records · Page 12Linked to original sources
PubMed1997

Sheathlin: cloning, cDNA/polypeptide sequences, and immunolocalization of porcine enamel sheath proteins.

Sheath proteins designate low-molecular-weight non-amelogenin enamel polypeptides and their parent protein, which concentrate in the sheath space separating rod and inter-rod enamel (Uchida et al., 1995). Two porcine sheath proteins, with apparent molecular weights of 13 and 15 kDa, are characterized by protein sequencing. The primary structures of these polypeptides match a portion of the derived amino acid sequences of clones isolated from a porcine enamel organ epithelia-specific cDNA library. Sheath protein RNA messages differ by the inclusion or deletion of a 45-nucleotide segment and by the use of three alternative polyadenylation/cleavage sites. The secreted proteins are 395 and 380 residues in length, with molecular masses of 42,358 and 40,279 Daltons and calculated isoelectric points of 6.3 and 6.7, respectively. Polyclonal antibodies were raised against a synthetic peptide having the sheathlin-specific sequence EHETQQYEYSGGC. Immunohistochemistry with this antibody demonstrates that the protein encoded by the sheathlin cDNA is preferentially localized in the sheath space. We propose that the porcine sheath proteins and their proteolytic cleavage products be designated "sheathlin".

Amino Acid Sequence↗
PubMed1997

Cloning and characterization of porcine enamelin mRNAs.

Dental enamel forms by matrix-mediated biomineralization. The components of the developing enamel matrix are generally specific for that matrix. The primary structures of three enamel proteins-amelogenin, tuftelin, and sheathlin (ameloblastin/amelin)-have been derived from cDNA sequences. Here we report the cloning and characterization of mRNA encoding a fourth enamel protein: enamelin. The longest porcine enamelin cDNA clone has 3907 nucleotides, exclusive of the poly(A) tail. The primary structure of the secreted protein is 1104 amino acids in length. Without post-translational modifications, the secreted protein has an isotope-averaged molecular mass of 124.3 kDa and an isoelectric point of 6.5. Polymerase chain-reaction phenotyping of enamelin cDNA suggests that porcine enamelin transcripts are not alternatively spliced and use a single polyadenylation/cleavage site. Immunohistochemical and Western blot analyses with an affinity-purified antipeptide antibody specific for the enamelin carboxyl terminus demonstrate that enamelin is synthesized and secreted by secretory-phase ameloblasts. The parent protein is a 186-kDa glycoprotein that concentrates along the secretory face of the ameloblast Tomes' process. Intact enamelin and proteolytic cleavage products containing its carboxyl terminus are limited to the most superficial layer of the developing enamel matrix, while other enamelin cleavage products are observed in deeper enamel.

Amino Acid Sequence↗
PubMed1997

[Ca2+ channels in the central nervous system].

Roles of Ca2+ channels in physiological functions of mammalian central synapses were discussed from a system-oriented point of view. In the presynaptic terminals of the mammalian CNS so far studied, synaptic transmission is mediated by the subclass of Ca2+ channels designated as the N-type (alpha 1B channels) and/or by that designated as the P/Q-type (alpha 1A channels). In some central synapses such as those between neocortical pyramidal neurons, synaptic transmission is presynaptically suppressed by various transmitter-modulators. Our electrophysiological data indicate that the receptors for amines, glutamate, GABA and adenosine co-exist on individual terminals, and they exert a common modulatory effect on synaptic transmission. Details of the intracellular cascade, i.e., G-protein and Ca2+ channel subtypes that are linked in this modulation, remain to be elucidated. Although the direct 'membrane delimited' action of G-proteins on Ca2+ channels is strongly suggested as a modulatory mechanism by the resemblance to the modulation observed in other neurons, the indirect second messenger pathways, however, may also be involved in the control of Ca2+ channels. Postsynaptically located Ca2+ channels are considered to play important roles in the regulation of neuronal excitability and synaptic plasticity. Individual dendritic spines apparently serve as a primary unit in an increase in Ca2+ level. This compartmentalized increase of Ca2+ seems essential for determining plastic changes of the synaptic efficacy in those particular spines. There is ample evidence indicating that the postsynaptic Ca2+ channels are involved in this Ca2+ transient. In order to understand the physiological significance of Ca2+ channels in CNS functions, further elucidation of channel subtypes, intracellular cascades of the modulator actions and characterization of the channel modifications will be essential.

Animals↗
PubMed1997

Phorbol 12-myristate 13-acetate (PMA)-induced oxyradical production in rheumatoid synovial cells.

We successfully detected the oxyradical production in human synovial A (macrophage-like) and B (fibroblast-like) cells by phorbol 12-myristate 13-acetate (PMA) using the luminol-chemiluminescence method. The PMA (0.1 microgram/ml)-induced photon generation was abolished by an O2- scavenger, superoxide dismutase, and an H2O2 scavenger, catalase, suggesting that the stimulus produced oxyradicals in synovial cells. Both of these responses were abolished by a protein kinase C (PKC) inhibitor, calphostine C, but unaffected by an intracellular Ca2+ chelator, BAPTA-AM, and Ca2+ removal from the extracellular medium. These findings suggest that synovial A and B cells produce oxyradicals through PKC-mediated and [Ca2+]i-independent mechanisms, probably through the activation of NADPH oxidase.

Arthritis, Rheumatoid↗
PubMed1997

[Localization and expression of matrix metalloproteinase-7 in human prostate].

BACKGROUND: Matrix metalloproteinases-7 (MMP-7), one of an extracellular matrixdegrading metalloproteinase, play an important role tumor invasion and metastasis. We investigated localization, biochemical characterization and mRNA expression of MMP-7 in prostate tissues. METHODS: Immunohistochemical method, SDS-polyacrylamide gel electrophoresis and northern blot analysis were performed using tissues of prostatic cancer, BPH and normal prostate. RESULTS: A latent proenzyme with Mr28,000 of MMP-7 was detected in the ductal epithelial cells of BPH and in the cytoplasm of cancer cell of the prostate. The ratio of mRNA expression in MMP-7/beta-actin was significantly higher in the tissue of the invasive prostatic cancer than those of normal prostate and BPH in northern blot analysis. CONCLUSIONS: These results suggest that MMP-7 may participate in the function of exocrine gland of normal prostate by preventing glandular obstruction and may play a role in invasion and metastasis of prostatic cancer.

Extracellular Matrix↗
PubMed1997

The regional distribution and cellular localization of mRNA encoding rat prostacyclin synthase.

The cloned cDNA for rat prostacyclin synthase was found to contain a 1503-bp open reading frame which encoded a 501-amino acid protein sharing 84.0% identity with the human enzyme. RNA blot analysis revealed that the rat prostacyclin synthase mRNA, as a single species of 2.1 kb, is expressed abundantly in the aorta and uterus. High levels of expression were also observed in the stomach, lung, heart, testis, liver, and skeletal muscle. Low but significant expression was also seen in the brain and kidney. Furthermore, the regional distribution and cellular localization of prostacyclin synthase mRNA were examined by in situ hybridization analysis of rat tissue sections. The definitive signals for the mRNA were localized in smooth muscle cells of the arteries, bronchi and uterus, and in the cells of the fibrous tunic surrounding the seminiferous tubules, which are characterized as smooth muscle cells. Besides smooth muscle cells, signals were also detected in the fibroblasts of the heart myocardium, lung parenchyma cells and kidney inner medulla tubules and interstitial cells.

Amino Acid Sequence↗
PubMed1997

[Evaluation of urinary excretion of free-cortisol in patients with abnormal pituitary-adrenal axes].

Since urine contains cross-reacting substances to anti-cortisol(F) antibody, we extracted F from urine samples with dichloromethane. Using this specific assay system for F with TDX dynapack(fluorescence polarization immunoassay system), clinical significance of urinary F was tested by measuring urine samples from normal subjects, patients with pituitary-adrenal diseases and liver cirrhosis, and pregnant. The circadian rhythm of urinary F was evaluated by using samples collected every 4-hour period. The amount of urinary excretions of F during 4 hours were the highest during between 4 a.m. to 8 a.m. and then gradually decreased reaching at the lowest level at between 0 a.m. and 4 a.m. in normal volunteers. Such circadian rhythm was not found in 6 patients with Cushing's syndrome. The urinary F levels in pregnant women started to increase in the samples from between 21 to 30 weeks of gestation, and the level was maintained even at the 5th day of post-partum. The urinary F levels in patients with liver cirrhosis were significantly lower than those for age-matched healthy volunteers. In patients with abnormal steroidogenesis, the urinary F levels in patients with Cushing's syndrome were extremely high, 165-3358 micrograms/day. On the other hands, those in patients with deficient steroid synthetase were 2.8-26.5 micrograms/day, and those in patients with neuroblastoma and pheochromocytoma were 7.8-43.8 micrograms/day. The urinary F levels were about 50-fold higher in the patients with Cushing's syndrome than those in the normal reference interval, whereas serum F and urinary 17-OHCS levels were only 2.5-fold and 7-fold higher than those healthy volunteers, respectively. These results indicate that the assay of urinary F extracted with dichloromethane is the most useful test for the diagnosis of Cushing's syndrome.

Adult↗
PubMed1997

[A case of primary orbital chondrosarcoma].

The case of a twenty-year-old male with orbital chondrosarcoma is reported. He visited National Defense Medical College Hospital because of reduced vision in the right eye since two months previously. His corrected visual acuity was 8/20 in the right eye and 20/20 in the left eye. Fifteen degrees lateral displacement of the right globe and limitation of right ocular movement were recognized. Right fundus examination revealed optic disc edema and protuberant nasal fundus. Orbital computed tomography (CT) demonstrated a high density area between the inner part of the right orbit and the ethmoid sinus. Magnetic resonance imaging (MRI) showed a smoothly outlined and low intensity (T1) space occupying lesion. This lesion was irregularly enhanced by gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA). This orbital tumor was removed by an anterior approach. Histopathological examination revealed well-differentiated chondrosarcoma (grade 1) as determined by small prominent chondromatous cell projection into the collagen fibrous stroma, and existence of binucleate cells in the hypercellular region. After the operation the disc edema disappeared and his corrected right visual acuity improved to 20/20.

Adult↗
PubMed1997

[A case of primary malignant melanoma of the esophagus].

A case of primary and malignant melanoma of the esophagus was reported. A 64-year-old male complaining of discomfort of anterior chest pain was admitted to our hospital for operation. Findings of upper G-1 X-ray and endoscopic examination revealed suspiciously malignant melanoma. Subtotal thoracic esophagectomy with R III dissection was performed. Operative findings included A0 N2 Pl0 M0 Stage III. Macroscopically it showed black-grayish colored polypoid tumors, 7 cm in size. The typical finding of junctional activity adjacent to the tumor mass and melanocytes were microscopically found. The patient received postoperative systemic chemotherapy, but was died of multiple liver and bone metastases 125 days after surgery. Malignant melanoma of the esophagus has extremely poor prognosis and none of effective therapies has been reported.

Esophageal Neoplasms↗
PubMed1997

[Recent trend toward development of community medicine].

The author evaluated the present status of community medical activities in Hokkaido from standpoint of various actual data obtained by recent investigation. As many districts are in the face of shortage of doctors, it is concluded to promote the following subjects, 1) strengthening of district center hospitals, 2) education and maintenance of community medical doctors, 3) synthetic system of health, medicare and welfare, and 4) introduction of multimedia system. Our foundation has started several new works, such as doctor center model system, training system of primary care doctor, and network activities of community doctors. It is mandatory to form wide consensus among the person concerned, such as client, doctor, medical association, university, and municipality.

Community Health Planning↗
PubMed1997

[Preanesthetic meals in elective surgical patients].

This study investigated the effect of preanesthetic meals on the volume and pH of gastric contents in forty elective surgical patients ranging in ages from 20 to 60 years. Twenty patients who were given either isotonic beverage 250 ml or apple juice 250 ml on the morning of the operative day were subjected as control group and twenty patients of the breakfast group took two slices of bread with the above drink. About seven hours following drinking and feeding, the mean values of gastric volume were 20.9 +/- 18.3 ml in the control group and 19.2 +/- 16.3 ml in the breakfast group. The mean values of gastric pH were 4.3 +/- 2.3 in the drink group and 4.6 +/- 2.3 in the breakfast group. There were no significant differences in the gastric volume and pH between the two groups. However, very small amount of the bread was detected in the gastric fluid of three patients in the breakfast group. As preanesthetic drinking and feeding are advantageous for reducing the anxieties of preoperative patients and also for their nutrition during operation, it is encouraging that eating two slices of bread did not induce a significant effect of gastric volume or pH. The minute fragment of bread seems to have no clinically significant effect.

Adult↗
PubMed1997

Relationship between duration of rheumatoid arthritis before knee joint surgery and HLA-DRB1 alleles: a retrospective study.

OBJECTIVE: To examine whether genetically determined factors can be used as predictors of requirement for knee joint surgery in the early phase of rheumatoid arthritis (RA). METHODS: We determined HLA-DRB1 alleles in 322 patients with seropositive RA by polymerase chain reaction and allele specific oligonucleotide probe techniques. Patients were classified into 3 groups (S/S, S/N, and N/N) based on their possession of two, one or no susceptibility alleles of RA, respectively. The stage of radiographic change in the knee joint determined using Larsen's standard film was compared to results of genotyping. Duration of RA before joint surgery in the 3 groups was also compared retrospectively. RESULTS: The median number of years to develop to stages I, II, III, and IV and the number of years of disease duration before total knee arthroplasty (TKA) were significantly shorter in the S/S group than in the S/N and N/N groups (p < 0.05). CONCLUSION: TKA was required earlier in the S/S group than in the S/N and N/N groups. This finding will affect planning of surgical management for RA based on anticipated courses.

Adult↗
PubMed1997

[Usefulness of measurement of hormones in urine samples collected during the night period for the diagnosis of endocrine disorders].

It has been known that the measurement of adreno-cortical and medullary hormones in urine for 24 hours is the best way for diagnosis of the disease state. This is not only because hormone release shows circadian rhythm but also because the urinary excretion of hormones reflects the total amount of hormones produced for 24 hours. However, the civilized people, particularly the workers, are too busy to correct urine for 24 hours. Therefore, we aimed to evaluate whether the urine sample corrected for only 12 hours during night is useful for the diagnosis of adrenal diseases. Circadian rhythm of hormones in urine was evaluated by correcting urine every 4 hours in 18 normal adults. Diurnal variations of 17-ketosteroids (17-KS) and 17-hydroxycorticosteroids (17-OHCS) were evident; they showed the peak value during 8 AM and 12 AM, and the trough during 0 AM and 4 AM. Similarly, urinary noradrenaline and adrenaline showed the peak value at day time and the trough at night time. However, the rhythm was not observed in urinary dopamine and vanilyl mandelic acid (VMA). Under consideration of outpatient's convenience, urine sampled during night (between 8 PM and 8 AM) was evaluated. The amount of hormones during night was 35.9-46.9% of the total amount of the day, and the deviation was relatively small. The reference intervals (mean +/- 2SD) were as follows; 17-KS (n = 56, 2.8 +/- 2.4 mg/12 hours), 17-OHCS (n = 56, 2.0 +/- 2.0 mg/12 hours), 17-KGS (n = 52, 3.6 +/- 3.6 mg/12 hours), free cortisol (n = 43, 14.3 +/- 14.2 micrograms/12 hours), noradrenaline (n = 50, 12.9 +/- 9.8 micrograms/12 hours), adrenaline (n = 50, 2.1 +/- 4.0 micrograms/12 hours), dopamine (n = 50, 134 +/- 194 micrograms/12 hours), VMA (2.3 +/- 2.4 mg/12 hours). When the night periods urine in patients with adrenal disorders such as virilizing adrenocortical carcinoma, pituitary adenoma, adrenocortical hydroxylase deficiency, Addison's disease, hypopituitarism, Cushing's syndrome, pheochromocytoma was analyzed, the respective urinary hormone level corresponding to each disease was significantly changed from the reference interval. These results indicate that analysis of urine sample during night has advantage over the daily urine because the difference between normal and disease state is augmented when measured urinary during night.

Adenoma↗
PubMed1997

Random amplified polymorphic DNA observed in Eucalyptus by PCR study with random primers.

A total DNA extracted from Eucalyptus globlus, E. citriodora, or a subspecies of E. gunnii (Maruha Yu-kari) being used as an template, Polymerase Chain Reaction (PCR) was performed with 40 kinds of commercially available random primers (Operon, OPA-01-20 and OPB-01-20). After electrophoresis of PCR-products on agarose gel, we analyzed the band pattern formed by DNA-fragments with 0.5-3.0 kbp as molecular weight. As a remuneration for the examination in which forty 10-mer arbitrary oligonucleotides were tried to be used as primers in PCR for each species, we found that 9 primers (for E. globlus) leads polymorphism, 6 primers for E. citriodora, and 6 primers for Maruha Yu-kari.

Base Sequence↗
PubMed1997

Identification of Eucalyptus citriodora clones micropropagated in tissue culture.

The extent of genetic identity observed in the young individuals which were micropropagated from a single Eucalyptus individual was analyzed by using DNA-fingerprinting. Among 40,000 tissue-cultured-seedings of E.citriodora, 200 plants were randomly chosen so that each total DNA might be extracted from their leaves. Using these DNAs as template, PCR was performed with some primers we found in advance that leads polymorphism for DNA of E. citriodora. In this study, all over the 200 cases, the band pattern formed cDNA fragment on a gel after electrophoresis was the identical one mutually.

Base Sequence↗
PubMed1997

Molecular basis of the altered gag p19 protein (MA) of the transformation-defective mutant of Rous sarcoma virus, tdPH2010.

The transformation-defective mutant of Rous sarcoma virus (RSV), tdPH2010, has a gag p19 (matrix; MA) protein which migrates on SDS-polyacrylamide gels faster than that of the parental (tsNY68) as well as other wild-type strains of RSV. To study the molecular basis of this altered migration pattern and its biological significance, the nucleotide sequence of the p19 region of tdPH2010 was determined. Comparison of the nucleotide sequence of tdPH2010 with that of the Schmidt-Ruppin A strain of RSV revealed a point mutation at nucleotide 755 (G to A), resulting in an amino-acid substitution at residue 126 of p19 (Glu to Lys). Acidic-methanol esterification of free carboxyl groups suppressed the difference in electrophoretic mobility of p19 between tdPH2010 and the wild-type virus. Recombinant virus constructs having the mutated gag region of tdPH2010 produced a p19 with the same electrophoretic mobility as the p19 of tdPH2010. We concluded that the point mutation caused the altered electrophoretic behavior of p19 of tdPH2010. The mutation had no effect on the growth of infected cells.

Amino Acid Sequence↗