Biomedical subjects

M Ohmori

Publications and source records attributed to M Ohmori.

At least 145 records · Page 8Linked to original sources

PubMed1993

Interaction between pullulanase from Klebsiella pneumoniae and cyclodextrins.

The interaction between pullulanase from Klebsiella pneumoniae and alpha-, beta-, and gamma-cyclodextrins and 6-O-alpha-glucosyl-alpha-cyclodextrin and 6-O-alpha-glucosyl-beta-cyclodextrin was examined by means of inhibition studies of the enzyme activity, UV difference spectroscopy, and flow calorimetry. All the above cyclodextrins were found to be competitive inhibitors, but beta-cyclodextrin and 6-O-alpha-glucosyl-beta-cyclodextrin showed strong inhibition, the inhibitor constants being two orders of magnitude less than those of alpha- and gamma-cyclodextrins. The difference spectra of beta-cyclodextrin were slightly but significantly different from those of the other cyclodextrins, showing blue shift of a few nanometers. Moreover, only beta-cyclodextrin has a positive entropy change upon binding with the enzyme; all the other cyclodextrins have negative values. These results show that the binding mode of beta-cyclodextrin is subtly different from those of alpha- and gamma-cyclodextrins.

Calorimetry↗

PubMed1993

MDS-macrophage derived inhibitory activity on myelopoiesis of MDS abnormal clones.

We studied the effect of myelodysplastic syndrome (MDS)-derived adherent cells on colony formation of granulocyte-macrophage progenitors (CFU-GM) in both normal and MDS bone marrow cells. MDS-adherent cells suppressed the growth of normal CFU-GM colony formation. Antibodies against ferritin almost totally neutralized the haematopoietic inhibitory activity. Antibody against gamma-interferon (gamma-IFN) did not have such effect. By cytogenetic analysis using G-staining method, MDS-derived CFU-GM colony showed abnormal clones. MDS have been recognized to be a mosaic of normal and abnormal clones. MDS-macrophages suppressed the growth of progenitor cells derived from normal clones by soluble factors, but did not suppress the growth of those from abnormal clones. It is suggested that progenitor cells derived from abnormal clones are freed from the negative myelopoietic regulator that may be related to the progress of leukaemia.

Adult↗

PubMed1993

Extracranial meningioma in the parapharyngeal space.

A case of extracranial meningioma in the parapharyngeal space is reported. A 24 year old woman presented with swelling and tenderness of the parapharyngeal region. A tumor was palpable in this region, and the tumor was surgically removed. Macroscopically the tumor occurred from the portion between the axis and atlas. Histologically the tumor cells, which had oval nuclei and a slightly eosinophilic cytoplasm, proliferated in fibrous connective tissues to form small nests. As the cell borders were not clear, the tumor structure appeared to be syncytium-like. Immunohistochemically the tumor cells were positive for anti-vimentin antibodies, anti-S-100 protein antibodies and anti-epithelial membrane antigen (EMA) antibodies in part. Electron microscopically the tumor cells had complex interdigitations of their adjacent plasma membranes. These were studded with many desmosomes. Bundles of intermediate filaments were visible in the cytoplasm. On the basis of the clinical, histological, immunohistochemical and electron microscopical features, the tumor was diagnosed as extracranial meningotheliomatous meningioma. The parapharyngeal space is an extremely rare location for extracranial meningioma, and our case is the first in Japan as far as we know.

Adult↗

PubMed1993

Lipofibromatous hamartoma of nerve in the foot.

A case of lipofibromatous hamartoma in the foot is described. This tumor-like lesion commonly occurs in the hands, wrists and forearms of young persons. The median nerve is affected in the great majority of cases. Only very rarely, however, is it found in the nerves of the foot. It is believed that the present study is the seventh reported case of lipofibromatous hamartoma in the foot, and is the first case reported in Japan. A review shall be made of the six reported cases in the foot.

Child↗

PubMed1993

Mixed mesodermal tumor of the ovary: immunohistochemical study with histogenetic consideration.

The clinical, histological and immunohistochemical features of three cases of ovarian mixed mesodermal tumor (MMT) were examined. The epithelial component was serous papillary cystadenocarcinoma in case 1 and 3, and endometrioid adenocarcinoma in case 2. In case 1, undifferentiated adenocarcinoma was also seen. The mesenchymal component was fibrosarcomatous and chondrosarcomatous in case 1 and 2. In case 3, only fibrosarcomatous area was seen. No endometriosis was observed. Immunohistochemically, the epithelial component showed positivity for epithelial membrane antigen in all three cases. S-100 protein was positive in two cases with chondrosarcomatous differentiation. The fibrosarcomatous area showed positivity for vimentin in all three cases. However desmin, myosin and myoglobin were negative. The antibodies thought to be epithelial or mesenchymal markers unexpectedly reacted positively in some cells; for example, EMA was positive in fibrosarcomatous and chondrosarcomatous cells. Therefore, it was speculated that because the undifferentiated tumor cells had a biphasic character, MMT might originate from immature multipotential cells of surface epithelium and subcapsular connective tissue of the ovary.

Aged↗

PubMed1993

Polymorphous low-grade adenocarcinoma of submandibular gland origin.

A case of polymorphous low-grade adenocarcinoma (PLGA) in the submandibular gland is reported. A 72 year old woman presented with a 5 year history of a gradually expanding tumor in the submandibular region. The surgical specimen revealed a relatively well demarcated tumor, 35 x 35 x 20 mm in size. Macroscopically, necrosis and hemorrhage were not seen in the solid tumor. Histologically, the tumor growth pattern was variable, composed of tubular, papillary, solid, trabecular and cribriform structures. Immunohistochemically, some tumor cells were positive for epithelial membrane antigen (EMA), S-100 protein, keratin, and carcinoembryonic antigen (CEA). Electron microscopically, prominent microvilli projected into the luminal spaces, and basal lamina and hemidesmosomes were seen in the tumor cells adjacent to the connective tissues. The submandibular gland is an extremely rare location for PLGA. To the authors' knowledge, this is the first case of its kind reported in the English literature.

Adenocarcinoma↗

PubMed1993

Immunodetection of TSH receptor antibodies in sera of patients with autoimmune thyroid disease by ELISA (enzyme-linked immunosorbent assay).

An ELISA system has been developed for detecting antibodies to TSH receptor peptides. It has been used to study antibodies against peptides corresponding to four different extracellular domains of human TSH receptor in the sera of patients with Graves' disease (N = 10, TBII positive) and Hashimoto's disease (N = 10, TBII negative). Two peptides, N (amino acid residues nos. 29-57) and P3 (nos. 359-371) are specific for TSH receptor, and two, C (nos 172-202) and P1 (nos. 398-417) are homologous with the corresponding portions of the LH/CG receptor. All of the peptides were recognized by sera from patients with Graves' disease but individual sera recognized different numbers and combinations of these peptides. Sera from patients with Hashimoto's disease did not bind to any of these peptides. These results suggest that antibodies to the TSH receptor in patients with Graves' disease recognize various regions of extracellular domain of TSH receptor in addition to TSH receptor-specific regions.

Amino Acid Sequence↗

PubMed1993

Uterine leiomyoma with a focus of fatty and cartilaginous differentiation.

A uterine leiomyoma with a focus of fatty and cartilaginous differentiation in a 58-year-old female is reported. The leiomyoma was located in the posterior uterine wall and had a maximum diameter of about 15 cm. A yellow hard nodule, about 5 cm in diameter, was found in the periphery of the leiomyoma and histologically was composed of cartilaginous tissue in islands with lipofibromyomatous tissue surrounding them. Generally so-called lipomatous lesions of the uterus include circumscribed or diffuse lipomatosis of a leiomyoma and pure lipoma. Although appearance of cartilaginous tissue in lipomatous lesions of the uterus has never been reported, this case should be a very special form of circumscribed lipomatosis of a uterine leiomyoma.

Adipose Tissue↗

PubMed1993

[The factors related to the stagnation in the decline of tuberculosis incidence in Japan].

The mortality from tuberculosis in Japan had extremely decreased from the end of the 1940's to the beginning of the 1950's, due to the end of chaos after World War II and also due to the introduction of antituberculosis drugs. The rapid decline of mortality usually leads to the reduction in the infection risk of tuberculosis in the general population. Such a drastic change in the history of tuberculosis have been dividing general population into two groups, i.e. those who were born during the rapid spread of infection with tubercle bacilli and others who were born after. With the passage of time, the limiting age between those two groups reached 40-50 years old as of 1980. The elderly people who were infected with tubercle bacilli in the remote past, have a high risk of development of tuberculosis by endogenous breakdown. In addition, the population of the aged in Japan has been expanding very fast as compared to that in European countries. Owing to such a change of historical and demographical background, the proportion of the elderly cases developed to tuberculosis have increased considerably and it played a major role in a small decrease of tuberculosis incidence rates since 1980. On the other hand, a generation gap on the prevalence of tuberculosis infection caused the recent smallest reduction rate of incidence among young adults. As the majority of young people have not been infected with tubercle bacilli, since 1980, the micro-epidemic among adolescent and young adults have been reported often.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1993

Small cell carcinoma of the prostate. A case report.

A case of small cell carcinoma of the prostate reported here was studied by immunohistochemical and electron microscopic procedures. Most tumour cells were positive for argyrophil (Grimelius) stain and had dense core neurosecretory granules in the cytoplasm. But immunohistochemical staining revealed vasoactive intestinal polypeptide and calcitonin only in a few cells, and it was still obscure what kinds of hormones were produced in this tumour. By dot blot hybridization, our case showed no amplification of myc family gene which is suggested to be associated with a poor clinical outcome in pulmonary small cell carcinoma.

Carcinoma, Small Cell↗

PubMed1992

Single subunit structure of the human thyrotropin receptor.

We have produced rabbit antibody against a synthetic peptide corresponding to N-terminal region of the extracellular domain of human thyrotropin receptor (hTSH-R) (N peptide, aminoacid residues 29-57). Western blot analysis revealed that N-peptide antibody recognized recombinant hTSH-R stably expressing in CHO-K1 cells as a mol. wt. about 104 kDa regardless in the presence or absence of disulfide-reducing agent. The band was not detected in untransfected CHO-K1 cells and no band was also stained by the antibody absorbed with N-peptide. In a reducing condition, the antibody also bound the rat receptor from FRTL5 cells as the same molecular size (104 kDa). These results clearly indicate that TSH-R is composed of a single subunit and that two subunit model for the TSH-R may reflect artifactual proteolytic cleavage of the receptor during membrane preparation.

Amino Acid Sequence↗

PubMed1992

Heterogeneous responses of recombinant human thyrotropin receptor to immunoglobulins from patients with Graves' disease.

Non-thyroid mammalian cells, CHO-K1 cells, stably expressing human thyrotropin receptor (CHO-TSH-R cells) were used for the assay of thyroid stimulating antibody (TSAb) activities of IgGs from 24 patients with Graves' disease and we compared them with the values obtained in porcine thyroid cells. A significant positive correlation was observed between the results given by CHO-TSH-R cells (hTSAb) and porcine thyrocytes (pTSAb) (r = 0.94, p less than 0.001). However, we found that hTSAb values of IgGs from 5 patients were extremely different from their hTSAb values. Four out of these 5 IgGs showed strong pTSAb activity but exhibited a weak or negative hTSAb activity. Conversely, one out of 5 autoantibodies was very strong for hTSAb but its pTSAb was low. These heterogeneous responses of recombinant hTSH-R to Graves' IgGs suggest that there exist different types of TSAb and also that the epitope(s) for TSAb may be different from case to case.

Animals↗

PubMed1992

Characteristics of frequency content of atrial signal-averaged electrocardiograms during sinus rhythm in patients with paroxysmal atrial fibrillation.

To clarify the characteristics of the frequency content of atrial signal-averaged electrocardiograms (ECGs) during sinus rhythm in patients with paroxysmal atrial fibrillation, P wave-triggered signal-averaged ECGs were recorded in 28 patients with and 34 control patients without paroxysmal atrial fibrillation. Fast Fourier transform analysis was performed on the 100-ms segment starting 75 ms before the end of the P wave. An area ratio (AR50) was calculated by dividing the area under the spectrum curve between 20 and 50 Hz, multiplied by 100, by the area between 0 and 20 Hz. Magnitude ratios (MR20, MR30, MR40 and MR50) were calculated by dividing the magnitude at 20, 30, 40 and 50 Hz, respectively, multiplied by 100, by the maximal magnitude of the entire signal. AR50 was significantly greater in patients with than without paroxysmal atrial fibrillation (62.3 +/- 34.2 vs. 42.4 +/- 18.4). MR20 and MR30 were also significantly greater in patients with than without paroxysmal atrial fibrillation (MR20 76.1 +/- 15.2 vs. 60 +/- 20.2; MR30 41 +/- 18.8 vs. 26.6 +/- 14.4), although no significant differences in MR40 or MR50 were observed between the two patient groups. The difference in MR30 between groups remained significant even after taking into account the presence of organic heart disease. It is concluded that, irrespective of the presence of organic heart disease, the terminal portion of the P wave contained significantly more components in the 20- to 50-Hz range, especially around 30 Hz, in patients with than in patients without paroxysmal atrial fibrillation. These results suggest that frequency analysis could characterize atrial signal-averaged ECGs of patients at risk for paroxysmal atrial fibrillation.

Adult↗

PubMed1992

Brain lesions of the Leigh-type distribution associated with a mitochondriopathy of Pearson's syndrome: light and electron microscopic study.

Pearson's syndrome is a disease of refractory sideroblastic anemia and exocrine pancreatic dysfunction due to abnormal mitochondrial DNA (mtDNA). A male infant with Pearson's syndrome developed necrosis of both thalami and basal ganglia when he suffered from gastroenteritis at 1 year and 11 months of age. He died of sepsis at the age of 2 years and 4 months. Analysis of mtDNA from various organs revealed abnormal mtDNA with deletion by 5 kbp, confirming the diagnosis. At autopsy, the brain had symmetrical cavities in putamen, caudate nuclei and medial nuclei of the thalami. Ferruginous granules in nerve cells in medial thalamic nuclei, and scattered round bodies with neuronophagia in lateral nuclei were found at light microscopic observation. Electron microscopy showed that these granules were composed of radiating spicules and a dense layer containing packed cytoplasmic organelles, respectively. The macroscopic distribution of brain lesions was very similar to and characteristic of Leigh's disease. This similarity leads to the supposition that defective intracellular energy utilization common to Leigh's disease could be responsible for brain lesions in this case. Although the histological appearance was somewhat atypical for Leigh's disease, very acute formation of brain lesions in this case was thought to have caused the histological difference.

Anemia, Sideroblastic↗

PubMed1992

Myelodysplastic syndrome (MDS)-associated inhibitory activity on haematopoietic progenitor cells: contribution of monocyte-derived lipid containing macrophages (MDLM).

We studied myelodysplastic syndrome-associated inhibitory activity (MDS-IA), which inhibited colony formation in vitro of normal granulocyte-macrophage progenitors (CFU-GM). When adherent marrow cells were incubated with fetal calf serum for 21-24 d, monocyte-derived lipid containing huge macrophages (MDLM) developed. MDLM from MDS marrow (MDS-MDLMs) and their conditioned medium (MDLM-CM) consistently suppressed the growth of normal CFU-GM colony formation. MDS-IA was active on CFU-GM during the S-phase and relatively resistant to heating. Monoclonal antibody against H subunit (acidic) ferritin and polyclonal antibody against placental ferritin neutralized the inhibitory activity of MDS-MDLMs. In addition, cell lysates of MDS-MDLMs reacted to both monoclonal anti-H subunit ferritin and polyclonal anti-placental ferritin in Western blotting analysis, indicating that the inhibitory activity was predominantly acidic isoferritin. On the other hand, MDLMs obtained from normal bone marrow had a CFU-GM enhancing activity. These results suggest that MDS-MDLMs may be responsible for the suppression of granulopoiesis in patients with MDS and that the suppression may be mediated by soluble factors, notably H subunit isoferritin.

Adolescent↗

PubMed1992

Benign fibrous histiocytoma of the renal capsule.

The first case of benign fibrous histiocytoma of the renal capsule is reported in a male aged 44 years. The tumor had its point of origin in the renal capsule. Histologically, the tumor was composed of intersecting fascicles of fibroblastic cells forming a loose crisscross or "storiform" pattern. Electron microscopic studies of tumor cells revealed intermediate filaments and membrane-bound collagen fibers which continued to extracellular collagen bundles. This deep seated fibrous histiocytoma had a more prominent storiform pattern and fewer secondary elements such as xanthoma cells than cutaneous ones.

Adult↗

PubMed1992

Establishment and characterization of cell lines from human adenovirus type 12-induced murine tumors producing endogenous virus particles.

Two cell lines designated IC-KMS and D-KMS were established from human adenovirus type 12-induced tumors of C3Hf/OK mouse. The cell lines retained the characteristics of the original tumor i.e., production of numerous C-type and intracisternal A-type particles, integration of Ad12 E1 region DNA and amplification of the myc gene family. Chromosomal analysis revealed chromosome aberrations in both IC-KMS and D-KMS cells. The modal chromosome number of IC-KMS cells was 54 and that of D-KMS cells was 48. Metacentric chromosomes and minichromosomes were found. Trisomy of chromosome 3, 7 and 12 was seen frequently in D-KMS cells. Although DNA aneuploidy was revealed by flow cytometry, the DNA indices of these cells showed no relation to the copy number of integrated Ad12 DNA. These cells have been propagated by serial culture during the past 17 months. Production of endogenous virus particles is a unique characteristic of IC-KMS and D-KMS cells. These cell lines would be useful materials for examining the contribution of Ad12 carcinogenesis to activation of endogenous virus particles, and also the correlation between Ad12 carcinogenesis and cancer-related genes.

Adenoviruses, Human↗

PubMed1992

Meningeal hamartoma of the scalp. A variant of primary cutaneous meningioma.

A case of meningeal hamartoma of the scalp is reported. A 15-year-old girl was admitted complaining of scalp nodules in the midline occipital region. A midline skull defect was found under the nodular lesions. Histologically, the mass had a fibrocollagenous tract extending to the dura and showed an admixture of mature adipose tissue, small vessels, strands of fibrocollagenous tissue, and scattered foci of meningocytes. Immunohistochemically, the meningocytes desmosomes, interdigitating processes, and intermediate filaments. The patient's brother also had the meningeal hamartoma of the scalp. Meningeal hamartoma as a variant of primary cutaneous meningioma is extremely rare, and this is the first report of such a case in Japan.

Adolescent↗