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S Hirota

Publications and source records attributed to S Hirota.

At least 181 records · Page 10Linked to original sources
PubMed1994

Transient and localized expression of bone morphogenetic protein 4 messenger RNA during fracture healing.

Temporal and spatial distribution of a gene encoding murine bone morphogenetic protein 4 (mBMP-4) during fracture repair were investigated in mice by RT-PCR and in situ hybridization. For in situ hybridization, fractured ribs and surrounding tissues were decalcified and hybridized with a mBMP-4-specific complementary RNA probe labeled with digoxigenin-11 UTP. mBMP-4 messenger RNA (mRNA) was not detected in ribs without fracture, whereas it was detected only in the early phase of fracture from 12 to 72 h after the onset of fracture before new cartilage or bone formation. The mBMP-4 mRNAs were present in cells distributed in three distinct regions, namely, the proliferating periosteum, the medullary cavity, and the muscles near the fracture site. These BMP-4-positive cells did not express bone gla protein mRNA, which is a marker of the mature osteogenic cell. RT-PCR also showed a transient increase in the level of BMP-4 mRNA in the early phase of fracture repair. The findings provide us with some new information. (1) The BMP-4 gene is produced by less differentiated osteoprogenitor cells, not by differentiated osteoblasts. (2) The BMP-4 gene is enhanced by the impact of fracture and localized in callus-forming tissue before callus formation. Together with the activities of BMP-4, as was previously described, our results suggest that newly produced BMP-4 gene product is one of the local contributing factors in callus formation in the early phase of fracture healing.

Animals↗
PubMed1994

Localization of the mRNA for bone matrix proteins during fracture healing as determined by in situ hybridization.

The expression of the mRNAs for osteonectin (ON), osteopontin (OPN), osteocalcin (OC), and matrix Gla protein (MGP) was studied by in situ hybridization during the healing process of an experimental fracture in adult rat femora. At day 1 postoperatively, ON mRNA was detected in the proliferating periosteum. At day 3, ON, OPN, and OC mRNAs were detected in woven bone. From day 5, MGP and ON mRNAs were detected in the immature chondrocytes. From day 7, ON, OPN, and OC mRNAs were detected in the osteoblastic cells in newly formed endosteal trabecular bone. OPN mRNA was also detected in some of the osteocytes in trabecular bone. From day 14, OPN and MGP mRNAs were detected in newly formed periosteal hypertrophic chondrocytes, and the ON, OPN, and OC mRNAs were detected in osteoblastic cells in newly formed periosteal trabecular bone. Although the cell types that expressed each mRNA in fractured bones were similar to those in embryonic bones, the time course of these mRNA expression in fractured bones was different from that in embryonic bones. We considered that this system is useful to investigate the phenotypic change in osteogenic and chondrogenic lineage cells that appears during fracture healing at the molecular level.

Animals↗
PubMed1994

Expression of mRNA of murine bone-related proteins in ectopic bone induced by murine bone morphogenetic protein-4.

To determine whether a system of ectopic bone formation induced by osteosarcoma-derived bone-inducing substance (bone morphogenetic protein-4) can be used as a model of developing bone at the molecular level, we studied the expression of bone-related protein mRNAs in the process of ectopic bone formation using non-radioisotopic in situ hybridization. Osteonectin mRNA was detected in fibroblast-like cells, which are similar to periosteal cells from the early to middle stages of bone development. The proportion of osteonectin mRNA-expressing cells was greater than that of osteopontin mRNA-expressing cells in hypertrophic chondrocytes and osteoblast-like cells. In contrast, osteopontin mRNA was localized in a limited population of hypertrophic chondrocytes, a single layer of osteoblast-like cells adjacent to the bone trabeculae in the middle stage of bone formation, and in a limited subset of osteocytes in the late stage. A strong osteocalcin mRNA signal was detected in osteoblast-like cells from the middle to late stages and in a limited subset of osteocytes in the late stage of bone development. Since the sequential gene expression pattern of bone-related proteins in the present system is comparable to that in embryonic osteogenesis, this system may be useful as a model for studying gene expression in osteogenesis.

Animals↗
PubMed1994

Alterations in the expression of osteonectin, osteopontin and osteocalcin mRNAs during the development of skeletal tissues in vivo.

Heterogeneity in the expression of three members of non-collagenous matrix proteins in osteogenic and chondrogenic development in vivo were investigated by in situ hybridization. Sections of several skeletal tissues from mice at various stages of development were hybridized with digoxigenin-labeled complementary RNA probes encoding osteonectin (Osn), osteopontin (Osp) and osteocalcin (Osc). In calvariae and mandibulae, Osn messenger RNA (mRNA) was detected in cells in pre-osseous and osseous tissues before mineralization. Osp mRNA was found in cells attached to the mineralized bone matrix together with Osn mRNA followed by the expression Osc mRNA. In long bones, mRNAs for Osn, Osp and Osc were sequentially expressed with bone development from primary spongiosa to diaphyseal bone. In growth cartilage, Osn mRNA was observed in chondrocytes in non-mineralized cartilage, whereas Osp mRNA was detected in hypertrophic chondrocytes in mineralized cartilage matrix with a characteristic switch in expression. Osc mRNA was not detected in any chondrocytes. These results indicate that osteogenic differentiation in bone development in vivo is characterized by the sequential expression of these three genes, and suggest that these genes are expressed differentially and specifically, in association with extra-cellular matrix mineralization.

Animals↗
PubMed1994

Colorectal tumours and pit pattern.

AIMS: To investigate the morphological and histopathological associations between an individual pit seen on stereomicroscopy or magnifying colonoscopy and an individual crypt seen in histological sections; and to examine these associations in colorectal tumours. METHODS: Fourteen thousand and twenty three cases were examined by colonoscope at Akita Red Cross Hospital. The surface mucosal pits of the lesions were observed using a magnifying endoscope in vivo and the pits of the extracted specimens were observed in vitro using a stereo microscope. Histological diagnoses were determined by light microscopy: the pit patterns in 100 glands were analysed. RESULTS: Pit pattern was classified into seven principal types: (1) normal round pit; (2) small round pit; (3) small asteroid pit; (4) large asteroid pit; (5) oval pit; (6) gyrus-like pit; and (7) non-pit. There was a correlation between pit pattern and the structure of the underlying crypt or gland. Furthermore, there was an association between pit pattern and the histology of the cells in the gland. Macroscopically, types 3, 4, 5, and 6 were common in protruding lesions. Type 2 was common in depressed lesions. The non-pit pattern was recognised in both. The depressed lesions had invaded the deeper layers more rapidly than protruding lesions. CONCLUSIONS: There were associations between individual pits and crypts. The branching carcinoma gland is thought to be the result of malignant transformation of the adenoma gland. The straight carcinoma gland is thought to result from the normal gland becoming malignant. The gland of the small round pit is thought to change from normal to the straight carcinoma gland via malignant transformation.

Adolescent↗
PubMed1994

Differential expression of protein kinase C genes in cultured mast cells derived from normal and mast-cell-deficient mice and mast cell lines.

We investigated the expression of mRNA of protein kinase C (PKC) isozymes (alpha, beta, gamma, delta, epsilon, xi, and eta) in cultured mast cells (CMC) derived from normal (+/+) mice, CMC derived from genetically mast-cell-deficient (W/W, Wv/Wv, and mi/mi) mice, and murine mast cell lines (IC2, MC9, and P-815) by Northern blotting. In +/+ CMC, abundant expression of PKC delta and moderate expression of PKC alpha and beta was observed, while other PKCs (types gamma, epsilon, xi, and eta) were not detected. In vivo expression of PKC delta was demonstrated in the skin by in situ hybridization. In mast cell lines, the expression pattern of PKC isozymes was similar to that of +/+ CMC, except that the expression of PKC eta was detected in the IC2 cell line. The expression levels of PKC delta in CMC derived from c-kit-deficient mutants, W/W, Wv/Wv, and mi/mi, were lower than that of +/+ mice. These results indicate that PKC delta is the main isozyme in various types of murine mast cells and also suggest that the reduced level of PKC delta expression in mutant mice may be caused by a deficit in the signal transduction system through c-kit receptor.

Animals↗
PubMed1994

[Clinical evaluation of dynamic MRI in the re-diagnosis of therapeutic effect and recurrence after transcatheter arterial embolization for hepatocellular carcinoma].

We evaluated re-diagnostic ability of dynamic MRI as compared with T2 weighted image in the diagnosis of primary therapeutic effect and tumor recurrence after transcatheter arterial embolization (TAE) for hepatocellular carcinoma. Thirty-four nodules in 30 patients with hepatocellular carcinoma were estimated based on operative and angiographic findings. According to the time when dynamic MRI was taken, nodules were classified as a short-term observation group consisting of 15 nodules obtained within a month after TAE, or as a long-term observation group consisting of 19 nodules obtained over a month after TAE. In the short-term observation group, sensitivity, specificity, accuracy was 89%, 100%, 93% on dynamic MRI and 78%, 67%, 73% on T2WI, respectively. In the long-term observation group, these were 94%, 100%, 95% on dynamic MRI and 100%, 33%, 89% on T2WI and 94%, 67%, 89% on Lipiodol-CT, respectively. In both groups, dynamic MRI was superior in accuracy. Conclusively, we consider that dynamic MRI is a most accurate diagnostic method that should be added to routine MRI after TAE. Especially in the case diagnosed positive on T2WI, the usefulness of dynamic MRI should be emphasized to determine the schedule of the therapy, because the cases that were false positive on T2WI were accurately diagnosed on dynamic MRI.

Aged↗
PubMed1994

Establishment and characterization of the T-cell line, EBT-8 latently infected with Epstein-Barr virus from large granular lymphocyte leukemia.

An Epstein-Barr virus (EBV) genome-positive T-cell line, designated EBT-8, was established from peripheral blood of a patient with EBV genome-positive large granular lymphocyte leukemia of T-cell origin. The cells have been cultured continuously in RPMI-1640 medium supplemented with 10% fetal calf serum and 40 U/ml interleukin-2 for more than 18 months. Analysis of T-cell receptor gene rearrangement demonstrated similar rearrangement between the fresh leukemic cells and EBT-8 cell line. The cell line has several azurophilic granules in its cytoplasm and activated cytotoxic/suppressor T-cell surface antigens (CD2, CD3, CD8, HLA-DR and T-cell receptor alpha/beta). Karyotypic analysis of the cell line showed several chromosomal abnormalities. EBV DNA was demonstrated in the cells by Southern blot hybridization and about five copies of covalently closed circular DNA per cell were detected by Gardella gel analysis. Clonotypic episomal EBV DNA was observed in the cells by Southern blot hybridization with EBV-terminal fragment probe. EBV-encoded small RNA, EBER1 were demonstrated in all cells by in situ hybridization. EBV-encoded proteins, EBNA and LMP1 were demonstrated by immunofluorescence technique. EBV activation was observed after 12-O-tetradecanoylphorbol-13- acetate treatment of the cells. These results demonstrated the establishment of a T-cell line with latent EBV genomes and suggested the involvement of EBV to the large granular lymphocyte leukemia of T cells.

Adult↗
PubMed1994

Expression of genes encoding connective tissue proteins in androgen-dependent SC115 tumors after androgen removal.

BACKGROUND: Shionogi carcinoma 115 (SC115) is an androgen-dependent medullary carcinoma with a compact cell pattern. When SC115 tumors grow in androgen-depleted hosts, spindle-shaped and round cells with abundant cytoplasm develop. These cells originate from the SC115 cells (Kitamura et al., Cancer Res 1979;39:4717; Terada et al., Lab Invest 1987;57:186). EXPERIMENTAL DESIGN: We investigated whether these spindle-shaped and round cells expressed mRNAs of noncollagenous connective tissue proteins, which are expressed by normal spindle-shaped cells and normal chondrocytes in developing bones. The expression and localization of osteonectin (OSN), osteopontin (OSP), matrix Gla protein (MGP), and osteocalcin (OSC) were determined by Northern blotting and in situ hybridization. RESULTS: No mRNA signals of these proteins were detectable in SC115 medullary carcinoma cells growing in DS mice that had been castrated but received injections of testosterone propionate. However, when the injection of TP was stopped, spindle-shaped and round cells with abundant cytoplasm developed. The former expressed OSN and OSP signals, and the latter OSN, OSP, and MGP signals. CONCLUSIONS: Transcripts of OSN, OSP, and MGP were expressed by some SC115-derived cells during the differentiation events that occurred after androgen removal. These results provide molecular biologic evidence that a tumor of epithelial origin can progress along the connective tissue differentiation pathway.

Amino Acid Sequence↗
PubMed1993

[Radiation therapy for carcinoma of vagina].

Thirty-four patients with carcinoma of the vagina were treated by radiotherapy at the Hyogo Medical Center for Adults between April 1965 and May 1990. All patients were treated with a combination of external and intracavitary or intestinal irradiation. Twenty-three patients had squamous cell carcinoma, five had adenocarcinoma and two had malignant melanoma. The five-year survival of patients with squamous cell carcinoma was 70% in Stage I (10 patients), 40% in Stage II (seven patients), 50% in Stage III (three patients) and 0% in Stage IV (three patients). Local control was achieved in 72.7% of the patients with squamous cell carcinoma and 60% of those with adenocarcinoma. However, neither of the malignant melanomas was controlled. Five patients had severe complications that required surgical treatment: severe proctitis and small-bowel perforation, ileus, rectal stenosis, vesicovaginal fistula and small-bowel perforation. Local and pelvic failure was noted in three patients. Patients with previous hysterectomy were more likely to develop serious treatment-related complications.

Adenocarcinoma↗
PubMed1993

[Radiotherapy for vulvar cancer].

Fifteen patients who had primary vulvar cancer treated with radiotherapy as an initial treatment at Hyogo Medical Center for Adults and Hyogo Cancer Center from January 1971 to December 1990 are presented. Two patients were stage 0, one stage I, three stage II and nine stage III. Nine patients received electron irradiation with or without interstitial irradiation and intracavitary vaginal irradiation. Five patients received megavoltage X-ray irradiation using AP/PA parallel opposed fields including the pelvic nodes and perineum followed by boost irradiation of electrons, interstitial irradiation and intracavitary vaginal irradiation. The total dose delivered to the primary tumor ranged from 50 to 100 Gy (73 Gy on average). The actuarial 5-year survival rate of the patients was 43.6%. Complete regression (CR) was achieved in 60% of the patients. However, CR was not achieved in any of five patients with palpable inguinal nodes. In contrast, all the patients who had tumors of less than 2 cm in diameter achieved CR. Five of nine CR cases relapsed. First sites of failure were vagina, groin and vulvar region. Recurrence occurred more than four years after treatment in three cases. Necrosis occurred in five of nine CR cases.

Adult↗
PubMed1993

Synthesis of galactose derivatives that render lectin-induced agglutinating ability to liposomes.

Three galactose (Gal) derivatives, Gal beta 1-n-C16H33 (1), Gal beta (1-4)-Glc beta 1-n-C16H33 (2), and Gal beta 1-(CH2CH2O)3-n-C16H33 (3), were synthesized and incorporated into liposomes prepared from egg yolk lecithin. Agglutination of these liposomes with Ricinus communis agglutinin was examined by following the change of turbidity. Liposomes containing 3 were effectively agglutinated in contrast to the cases of 1 and 2, suggesting that the oxyethylene groups act as a favorable spacer to extrude Gal groups into the water. Differential scanning calorimetry showed that 3 was mixed with egg yolk lecithin at room temperature, but 1 and 2 were in the gel state, resulting in the phase separation that makes the recognition of Gal residue with Ricinus communis agglutinin difficult.

Calorimetry, Differential Scanning↗
PubMed1993

Developmental expression of flt3 mRNA in the mouse brain.

The expression and localization of flt3 mRNA were investigated using Northern blotting and in situ hybridization during the developmental process of the mouse brain. By Northern blotting, the expression of the flt3 gene was not detected in embryonic, neonatal, or early postnatal brains, but was markedly increased with age. In adult mice, flt3 was abundantly expressed in the cerebellum, moderately in the pons, and faintly in the thalamus and the cerebral cortex. By in situ hybridization, some neurons that expressed flt3 formed synaptic connections with each other. The present findings suggest that the flt3 gene expression is related to the cell type and the developmental process.

Age Factors↗
PubMed1993

PKC gamma gene expression is delayed in postnatal central nervous system of mi/mi mice.

In the central nervous system (CNS), the expression of protein kinase C (PKC) genes is strictly controlled by the developmental stage. We have examined the expression of PKC genes (cPKC alpha, beta, gamma, and nPKC delta, epsilon) in the process of the postnatal development in normal (+/+) C57BL/6 and microphthalmic (mi/mi) C57BL/6 mouse brains by Northern blotting and in situ hybridization. By Northern blotting, the expression level of cPKC gamma mRNA in mi/mi mice was significantly lower than that in +/+ littermates at d 9, 13, and 17. By in situ hybridization analysis, cPKC gamma mRNA-positive cells were detected in hippocampal and Purkinje cells in +/+ and mi/mi mice, but the magnitude of the signals in mi/mi mice was lower than that of +/+ mice, and the number of positive cells was smaller, whereas other isozymes (cPKC alpha, beta, and nPKC delta, epsilon) showed no significant difference between normal and mi/mi mice. The neuronal morphometric analysis by anti-P400 antibody revealed the same number and expression level of P400 protein in cerebellar Purkinje cells compared with +/+ mice. These results indicate that the deficiency of mi gene product causes the delayed expression of the cPKC gamma gene.

Animals↗
PubMed1993

Stem cell factor induces outgrowth of c-kit-positive neurites and supports the survival of c-kit-positive neurons in dorsal root ganglia of mouse embryos.

The c-kit receptor tyrosine kinase is highly expressed by about 10% of the neurons in the dorsal root ganglia (DRGs) of mouse embryos. We investigated the in vitro effect of stem cell factor (SCF), the ligand for c-kit receptor, on DRGs. Recombinant murine SCF (rmSCF) induced the outgrowth of c-kit-positive neurites from DRGs of normal (+/+) embryos. The effect of SCF was dose dependent and completely abolished by anti-c-kit ACK2 monoclonal antibody (mAb). Some neurites whose outgrowth was induced by nerve growth factor (NGF) were c-kit-positive, but anti-NGF mAb did not inhibit the rmSCF-induced neurite outgrowth. rmSCF did not induce neurite outgrowth from DRGs of W/W embryos that did not express c-kit receptors on the cell surface and of W42/W42 mutant embryos that expressed c-kit receptors without tyrosine kinase activity. rmSCF also had a trophic effect on c-kit-positive neurons in the culture of dissociated DRG cells. Most c-kit-positive neurons appeared to respond to NGF as well, and the SCF-responsive subpopulation represented about 10% of NGF-responsive neurons. rmSCF did not support the survival of DRG neurons from embryos of W/W and W42/W42 genotypes. These results suggest that the stimulus through the c-kit receptor tyrosine kinase has an important role in development of the peripheral nervous system.

Animals↗
PubMed1993

Possible involvement of c-kit receptor and its ligand in increase of mast cells in neurofibroma tissues.

Many mast cells are present in the tumor tissues of neurofibromatosis 1. We investigated the mechanism of the mast cell increase. Since the stem cell factor (SCF) induces development of mast cells and since the receptor of SCF is encoded by the c-kit gene, we examined the expression of SCF mRNA and c-kit mRNA in neurofibroma tissues. In situ hybridization demonstrated strong expression of c-kit messenger RNA in mast cells in the neurofibroma, but the expression of SCF mRNA was not demonstrable by in situ hybridization in either neurofibroma tissues or control normal skin tissues. When RNA extracted from neurofibroma tissues or normal skin tissues was reverse transcribed and then amplified by the polymerase chain reaction, the amount of SCF cDNA was greater in neurofibroma tissues than in normal skin tissues. The results suggest that SCF and the c-kit receptor are associated with the increase of mast cells in neurofibroma tissues.

Adolescent↗
PubMed1993

[Effect of training fitness on obesity, hypertension, hyperlipidemia and disorders in glucose metabolism].

Effects of physical training on obesity, hypertension, hyperlipidemia and disorders of glucose metabolism were investigated in 359 males, 30-59 years of age. Body mass index (BMI), systolic and diastolic blood pressure (SBP and DBP), high density lipoprotein cholesterol (HDL-C), total cholesterol (TC) and fructosamine (FA) were measured before and after the 2 month period of physical training at intensities of about 50% of maximal O2 uptake. Results are summarized as follows; 1. Means of BMI, SBP, DBP, TC and FA after the training were significantly lower than before the training. Mean of HDL-C was significantly higher than before the training. 2. In subjects with high BMI (n = 124), high SBP (n = 129) and high DBP (n = 128), means of BMI, SBP and DBP decreased with increase of training time per week. In subjects with low HDL-C (n = 104), high TC (n = 135) and high FA (n = 66), changes in means of TC, HDL-C and FA after the training did not show a relationship to training time per week. 3. Differences observed for measured values before and after the training of 2-3 hours per week were 0.4 kg/m2 in BMI, 15 mmHg in SBP and 10 mmHg in DBP, suggesting that training of 2-3 hours per week was effective in intervention of obesity and hypertension.

Adult↗