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Biomedical subjects

T Koike

Publications and source records attributed to T Koike.

At least 451 records · Page 25Linked to original sources
PubMed1995

Interferon-alpha-induced apoptosis in human erythroid progenitors.

Recombinant human interferon-alpha (rIFN-alpha) inhibits erythropoiesis, in vivo and in vitro. In an attempt to clarify mechanisms related to this inhibition, effects of rIFN-alpha on highly purified human peripheral blood burst-forming units-erythroid (BFU-E) (20-60% purity) were compared with effects on erythroid progenitors in various stages of development. Day-1 and -7 cultured cells were equivalent to primitive BFU-E and colony-forming units-erythroid (CFU-E), respectively. Day-1 BFU-E supported by recombinant human erythropoietin (rEpo) and interleukin-3 (rIL-3) was inhibited by rIFN-alpha in a dose-dependent manner, and a significant inhibition occurred at 2000 U/mL rIFN-alpha. Limiting dilution analysis demonstrated that rIFN-alpha directly inhibits BFU-E rIFN-alpha inhibited the proliferative capacity or the colony expression of erythroid progenitors, with no relation to the stage of development, but inhibition of differentiation was not apparent. This evidence suggested that apoptosis of erythroid progenitors was induced by IFN-alpha. When day-7 cells were incubated with IFN-alpha in the presence of rEpo, there was an increased breakdown of total cellular DNA into DNA fragments of less than 5 kb; hence, the inhibitory effect of IFN-alpha on erythroid progenitors may mediate apoptosis.

Adult↗
PubMed1995

[The structure and function of cadherins and their pathophysiological roles in diseases].

Cadherins are a family of Ca(2+)-dependent cell adhesion molecules that mediate cell adhesion by homophilic interaction and play critical role in multicellular organ formation. Recent progress revealed the three-dimensional structure of extracellular cadherin repeats that made great progress in the study of cell adhesion by cadherins. The perturbation of cadherin function in transformed cells results in inhibition of cell-cell adhesion, that appears to promote metastasis and invasiveness of tumor cells. Expression as well as modifications of catenins, which link cadherins to cytoskeletons, have crucial effects on this purturbation mechanisms. Tyrosine phosphorylation of cadherin catenin complex may be the important regulatory mechanism.

Cadherins↗
PubMed1995

[Resection of lung cancer complicated by pleural empyema].

In a 53-year-old man, carcinoma of the lung was resected and was complicated by pleural empyema. Two days after fiberoptic bronchoscopy, he developed a high fever and was found to have pleural empyema. After thoracic drainage and other palliative treatment, the right lower lobe and empyema cavity were resected. The postoperative course was uneventful and he was discharged 3 weeks after the operation, but he died of cervical and intrathoracic lymph node recurrence 5 months later. Surgical treatment of malignant lung cancer complicated by pleural empyema has been reported 10 times, including 3 reports from Japan. According to those reports, post-operative complications are rare, and long survival is possible. Therefore, surgical resection is indicated in some cases.

Carcinoma, Squamous Cell↗
PubMed1995

Radiological evaluation of disease progression in rheumatoid arthritis.

X-ray photographs of the wrist joints in 210 cases of Rheumatoid Arthritis (RA), who visited an outpatient clinic for RA in Orthopedic Department of the Osaka City Medical School were investigated using Carpo-Metacarpal Ratio (CMR) and Shinomiya's criteria, more detailed classification system based on the staging criteria of Steinbrocker. Radiological staging of the wrist joints revealed a correlation with the duration of RA and was considered to be a useful parameter in disease assessment. Radiological alterations in the wrist joints were progressive, but with great individual differences.

Arthritis, Rheumatoid↗
PubMed1995

[A comparative study of tazobactam/piperacillin and piperacillin in bacterial pneumonia].

The efficacy, safety and usefulness of tazobactam/piperacillin (TAZ/PIPC), in bacterial pneumonia and lung abscess were determined with PIPC as the control in a multi-institutional comparative study a penicillin antibiotic for injection prepared by combining a newly developed beta-lactamase inhibitor, tazobactam (TAZ), with a broad spectrum penicillin antibiotic, piperacillin (PIPC), at a ratio of 1:4. TAZ/PIPC was intravenously injected at a dose of 2.5 g (titer) twice a day, and PIPC at a dose of 2.0 g (titer) twice a day as a rule for 14 days. The following results were obtained: 1. The efficacy rates for bacterial pneumonia and lung abscess were 94% (80/85) in TAZ/PIPC group and 89% (70/79) in PIPC group, showing no significant difference between the two groups. 2. In a comparison of degrees of improvement in clinical symptoms, signs and laboratory findings, there were no significant differences between the two groups except for results on thoracic rales after three days of administration. 3. As for bacteriological effects, the elimination rates of causative organisms were 98% (40/41) in the TAZ/PIPC group and 80% (28/35) in the PIPC group. Thus, the TAZ/PIPC group was significantly superior to the PIPC group. The TAZ/PIPC group showed significantly better eradication of bacteria as well. Bacteria considered to be pyogenic were detected in 80 patients (43 administered TAZ/PIPC and 37 administered PIPC), but beta-lactamase production was confirmed in only 11 patients of each group. There were no significant differences in bacteriological effects among these patients. Minimum inhibitory concentrations of TAZ/PIPC against beta-lactamase producing organisms were distinctly superior to those of PIPC. 4. Side effects occurred in 10% (10/96) of the TAZ/PIPC group and 7% (7/95) of the PIPC group. Abnormal clinical laboratory test values were observed in 22% (20/92) of the TAZ/PIPC group and 18% (17/93) of the PIPC group. Thus, there were no significant differences between the two administration groups. 5. The usefulness rate in the TAZ/PIPC group was 87% (75/86) and it was 85% (67/79) in the PIPC group, showing no significant difference between them. The results suggest that TAZ/PIPC administered at a dose of 2.5 g (titer) twice a day is more useful than PIPC administered at a dose of 2.0 g (titer) twice a day in the treatment of bacterial pneumonia.

Adult↗
PubMed1995

[Essential thrombocythemia in transformation to smouldering megakaryoblastic leukemia with myelofibrosis].

Leukemic transformation in essential thrombocythemia (ET) is rare. We describe a patient with ET which transformed to megakaryoblastic leukemia with myelofibrosis after treatment with melphalan for 8 years. His course after transformation smouldered for 20 months without antileukemic chemotherapy. A 61-year-old man was referred by a local doctor to Niigata University Hospital due to nasal bleeding in June 1984. Complete blood count (CBC) was as follows; hemoglobin 12.4 g/dl, platelets 268.8 x 10(4)/microliters, and white blood cells 11,900/microliters, with differentials of 39% PMN, 1% basophils, 2% eosinophils, 4% monocytes, and 13% lymphocytes. Bone marrow examination revealed hyperplasia of megakaryocytes without increase of reticulin fibers. Neutrophil alkaline phosphatase activity and karyotype of marrow cells were normal. ET was diagnosed. He was followed up by local doctor. The platelet count was controlled at a level of approximately 40 x 10(4)/microliters with melphalan for eight years. In January 1992 he developed pain in his lower extremities. He was admitted to our hospital on May 29, 1992. CBC was as follows; hemoglobin 8.9 g/dl, platelets 14.3 x 10(4)/microliters, and white blood cells 3,500/microliters, with differentials of 25% PMN, 5% monocytes, 28% lymphocytes, and 24% blasts. Bone marrow aspiration was unsuccessful and bone marrow biopsy revealed increases in fibroblasts and collagen fibers. Circulating blasts were positive for CD4, CD7, CD25, CD13, CD33, CD34, and HLA-DR and partly positive for CD41 and CD36. In ultrastructural cytochemistry blasts were positive for platelet peroxidase but negative for myeloperoxidase. Cytogenetic study revealed 46, XY, +der (1) t(1:7) (p11;q11) in all of five metaphases. He was diagnosed with megakaryoblastic leukemia accompanied by myelofibrosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

[Successful treatment of hemopneumothorax with intrapleural OK432 in pulmonary metastases of cutaneous angiosarcoma].

An 80-year-old woman with angiosarcoma of the scalp was treated with radiation and interleukin 2. The patient experienced dyspnea one month later because of pulmonary metastases, and underwent video-assisted thoracoscopic surgery for a right pneumothorax. Right hemopneumothorax recurred 3 weeks after the surgery and left hemopneumothorax occurred 4 months later. Both were successfully treated with intrapleural OK432 and drainage. As of March 1995 the patient had been alive and well for one year since the right pneumothorax developed.

Aged↗
PubMed1995

Nondetectable cone and rod electroretinographic responses in a patient with Cockayne syndrome.

A 10-year-old girl complained or poor vision in both eyes. The patient showed progeria, physical and mental retardation, sensorineural hearing loss, cutaneous photosensitivity, hyperopia, poor pupillary dilation, exotropia, salt-and-pepper fundi, nondetectable cone and rod electroretinographic (ERG) responses, cerebral atrophy on computed tomography, and demyelination of periventricular white matter on magnetic resonance imaging. We believe that nondetectable cone and rod ERG responses in Cockayne syndrome, as demonstrated in our patient, may be uncommon.

Brain↗
PubMed1994

Transcription of the MRP RNA gene in frog stage I oocytes requires a novel cis-element.

The RNA component of the mitochondrial RNA processing (MRP) enzyme is related to both replication of mitochondrial DNA and processing of 5.8S rRNA, which are accelerated in the frog earliest stage (stage I) of frog oocytes. Microinjection of the deleted genes into the stage I oocytes showed positive cis-elements in the upstream region of the gene. The specific binding of protein(s) to this region was detected in cell extracts from stage I oocytes and liver but not in extracts of stage II-IV oocytes and the concentration of this protein was 40 times higher in the extract of stage I oocytes than that in liver.

Animals↗
PubMed1994

Novel retinoic acid, 9-cis retinoic acid, in combination with all-trans retinoic acid is an effective inducer of differentiation of retinoic acid-resistant HL-60 cells.

Recent studies have shown that a high proportion of patients with acute promyelocytic leukemia (APL) achieve complete remission after treatment with all-trans retinoic acid (RA). Nevertheless, despite an initial good response, most patients that received continuous treatment with all-trans RA relapse and develop RA-resistant disease. The 9-cis RA is a high-affinity ligand for retinoid X receptors (RXRs) and also binds efficiently to retinoic acid receptors (RARs); all-trans RA is a ligand for RARs. Both alone are able to induce differentiation of wild-type HL-60 cells. We found that neither all-trans RA nor 9-cis RA (< 2 x 10(-6) mol/L) induced differentiation of RA-resistant HL-60 cells into either mature granulocytes or monocytes. However, morphologic differentiation of the RA-resistant HL-60 cells was induced by 10(-6) mol/L all-trans RA combined with various concentrations (10(-12) to 10(-6) mol/L) of 9-cis RA. Electron microscopic examination also confirmed that the combination of both retinoids induced RA-resistant HL-60 cells to differentiate to mature granulocytes. Functional analysis of differentiation (NBT reduction activity) confirmed the necessity of both analogs to induce differentiation. Also, expression of myeloid-specific differentiation antigens (CD11b and CD14) as well as migration inhibitory factor-related protein (MRP)-8/14 mRNAs were upregulated only in the presence of both retinoids in a dose-dependent manner. In these conditions 3H-thymidine incorporation was inhibited and numbers of viable cells were decreased, suggesting that all-trans RA with 9-cis RA may inhibit cell growth and induce differentiation of RA-resistant HL-60 cells into mature granulocytes. These studies suggest that 9-cis RA in combination with all-trans RA is an effective inducer of RA-resistant HL-60 cells and may have implications for both the biology of retinoids and clinical treatment of RA-resistant acute myelogenous leukemia, including APL patients.

Antigens, Differentiation↗
PubMed1994

Novel precolumn deproteinization method using a hydroxyapatite cartridge for the determination of theophylline and diazepam in human plasma by high-performance liquid chromatography with ultraviolet detection.

The deproteinization of human plasma was carried out using a hydroxy apatite cartridge as a precolumn. After human plasma had been passed through the cartridge followed by suitable elution, protein-free eluate was obtained within only 1 min without the need for centrifugation. Deproteinization was evaluated by the determination of albumin, gamma-globulin and transferrin in the eluate by high-performance liquid chromatography (HPLC) with UV detection. Determination of theophylline and diazepam in human plasma was performed by HPLC with UV detection. The proposed method was suitable for the determination of these two drugs in human plasma, because it is simple and rapid (retention time of each drugs approximately 15 min) and microamounts of sample are required (50-100 microliters). The calibration graphs for theophylline and diazepam were linear in the range 0.1-10 micrograms and 0.1-65 ng, respectively. Recoveries of both drugs were over 90% by the standard addition method.

Albumins↗
PubMed1994

Anticardiolipin antibodies recognize beta 2-glycoprotein I structure altered by interacting with an oxygen modified solid phase surface.

Anticardiolipin antibodies (aCL) derived from the sera of individuals exhibiting the antiphospholipid syndrome (APS) directly bind to beta 2-glycoprotein I (beta 2-GPI), which is adsorbed to an oxidized polystyrene surface. Oxygen atoms were introduced on a polystyrene surface by irradiation with electron or gamma-ray radiation. X-ray photoelectron spectroscopy revealed the irradiated surfaces were oxidized to generate C-O and C = O moieties. aCL derived from either APS patients or (NZW x BXSB)F1 mice bound to beta 2-GPI coated on the irradiated plates, depending on the radiation dose. Antibody binding to beta 2-GPI on the irradiated plates was competitively inhibited by simultaneous addition of cardiolipin (CL)-coated latex beads mixed together with beta 2-GPI but were unaffected by addition of excess beta 2-GPI, CL micelles, or CL-coated latex beads alone. There was a high correlation between binding values of aCL in sera from 40 APS patients obtained by the anti-beta 2-GPI enzyme-linked immunosorbent assay (ELISA) using the irradiated plates and those by the beta 2-GPI-dependent aCL ELISA. Therefore, aCL have specificity for an epitope on beta 2-GPI. This epitope is expressed by a conformational change occurring when beta 2-GPI interacts with an oxygen-substituted solid phase surface.

Animals↗
PubMed1994

Existence of nuclear-encoded 5S-rRNA in bovine mitochondria.

A number of proteins functioning in mitochondria are synthesized in the cytoplasm and imported into the mitochondria via specific transport systems. In mammals, on the contrary, mitochondrial membranes have generally been considered to be impermeable to nucleic acids. However, here we show that an RNA with 120 nucleotides, the sequence of which is identical to that of the nuclear-encoded 5S RNA, exists in bovine mitochondria, although the mitochondrial genome encodes no 5S RNA gene. This RNA molecule was found to be retained in purified bovine mitochondria as well as in the mitoplasts, even after extensive treatment with an RNase, demonstrating that the 5S RNA is actually located inside the mitochondrial inner membrane. The 5S rRNA molecule was also shown to exist in mitochondria from rabbit and chicken.

Animals↗
PubMed1994

IL-5 mRNA expression in blood lymphocytes from patients with Kimura's disease and parasite infection.

Blood lymphocytes from patients with eosinophilia are known to produce interleukin-5 (IL-5) with appropriate stimulation in vitro. To determine whether blood lymphocytes from these patients produce IL-5 in vivo, we tested the IL-5 mRNA expression in blood lymphocytes immediately after separation by reverse-transcriptase polymerase chain reaction (RT-PCR) method. We found that lymphocytes from eosinophilic patients expressed IL-5 mRNA, but lymphocytes from normal volunteers did not express the lymphokine. These findings suggest that in patients with eosinophilia, peripheral blood lymphocytes produce IL-5 in vivo.

Adult↗
PubMed1994

Expression of sequences homologous to HTLV-I tax gene in the labial salivary glands of Japanese patients with Sjögren's syndrome.

OBJECTIVE: To address the question of whether the human T cell leukemia virus type I (HTLV-I) gene is associated with the etiology of Sjögren's syndrome (SS). METHODS: RNA expression of HTLV-I gag, pol, env, and tax genes in labial salivary glands (LSGs) from SS patients who were seronegative for antibodies to HTLV-I was examined using reverse transcription and polymerase chain reaction techniques. RESULTS: The HTLV-I tax gene, but not the HTLV-I gag, pol, or env genes, was detected in LSG samples from 4 of 14 patients (29%). The nucleotide sequences of the HTLV-I pXIV region in these 4 patients' LSGs showed 100% homology to the HTLV-I pXIV gene from the MT-2 cell line. CONCLUSION: These findings suggest that products encoding sequences homologous to the HTLV-I pXIV gene in SS patients' LSGs might be candidates for self-antigen and/or lead to activation of autoreactive T lymphocytes through trans-acting transcriptional activation.

Base Sequence↗