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Biomedical subjects

J Tamura

Publications and source records attributed to J Tamura.

At least 163 records · Page 9Linked to original sources
PubMed1992

Cell kinetics of regenerating liver after 70% hepatectomy in rats--2-color flow cytometric analysis.

Two-color flow cytometric (FCM) analysis using anti-bromodeoxyuridine (BrdU) monoclonal antibody (MoAb) was used to investigate the cell kinetics of regenerating liver after 70% partial hepatectomy in rats. Three peaks were seen in DNA histograms of rat hepatocyte nuclei, corresponding to diploid(2c), tetraploid(4c), and octaploid(8c). These proportions changed in the course of regeneration which were clearly demonstrated by DNA histograms using flow cytometry. The proportion of diploid, tetraploid, and octaploid nuclei in control liver were 49.3 +/- 1.6%, 45.0 +/- 7.4%, and 1.7 +/- 0.7%, respectively. A significant change occurred at 24 hours after hepatectomy, as FCM revealed 25.9 +/- 1.1% diploid, 54.5 +/- 1.2% tetraploid, and 9.0 +/- 0.9% octaploid. This shift to polyploid nuclei persisted until 72 hours, and then gradually returned to the pattern of control liver. The S-phase nuclei which incorporated BrdU increased rapidly at 24 hours to a peak of 11.3 +/- 0.9%, and gradually decreased to 5.8 +/- 0.8%, 5.3 +/- 0.8%, 2.4 +/- 0.6%, 2.9 +/- 1.1%, and 1.2 +/- 0.6%, at 48, 72, 96, 120, and 168 hours, respectively. This 2-color FCM analysis made a detailed analysis of the cell kinetics in regenerating hepatocytes possible, and may be applied in investigations of various aspects of liver regeneration.

Animals↗
PubMed1992

Prognostic relevance of morphological classification in multiple myeloma.

One hundred and twenty-two patients with multiple myeloma were classified as mature, intermediate, immature, or plasmablastic subtype according to Greipp's criteria. Contrary to Greipp's report, the survival time of plasmablastic myeloma was not significantly shorter than other subtypes, nor was the plasmablastic subtype identified as a poor prognostic factor. The survival time of mature plus intermediate myeloma was significantly longer than that of immature plus plasmablastic myeloma. Between the former and latter, significant differences were found for sex, clinical stage, thrombocytopenia, bone marrow plasmacytosis, renal insufficiency, bone destruction, and response rate to treatment. Therefore, it was suspected that the immature and plasmablastic subtypes were unfavorable prognostic factors in patients with multiple myeloma.

Aged↗
PubMed1992

Agranulocytosis during treatment with fluconazole.

Fluconazole, a new effective triazole antifungal agent, has been reported to cause fewer adverse reactions than amphotericin B. A patient who was diagnosed as having agranulocytosis and thrombocytopenia after treatment with fluconazole was investigated and recovered after withdrawal of the antifungal therapy. This case suggests the need for careful haematological observation during the treatment with fluconazole.

Adult↗
PubMed1992

Effects of long-term running on lymphocyte subpopulations.

Thirteen healthy members (11 males and 2 females; mean age 19.8 years) of an athletic club underwent a long-term exercise program (five 8-km runnings per week for 40 weeks) as regular training for their club. The circulating lymphocyte number, T lymphocyte percentage, and OKT4/OKT8 ratio did not change through the 40-week training period. However, suppressor/inducer (Leu3a+Leu8+) and suppressor T cells (Leu2a+Leu15+) significantly increased. In contrast, helper (Leu3a+Leu8-) and cytotoxic T cells (Leu2a+Leu15-) significantly decreased. On the other hand, there was no change in three males (mean age 18.7 years) without the long-term exercise program. These results suggest that long-term running may induce some change in lymphocyte subpopulations.

Adult↗
PubMed1992

A long-term survivor with malignant thymoma accompanied with pure red cell aplasia.

A 56-year-old woman with malignant thymoma lived for 19 years after diagnosis and died of superior vena cava syndrome. An autopsy showed invasion of the thymoma to the right lung and metastasis to the left lung. The pathologic diagnosis was epithelial thymoma (spindle cell dominant) accompanied with pure red cell aplasia (PRCA). However, this was well controlled with steroid therapy. She was the longest survivor with malignant thymoma at this time. Her long-term survival may be the result of good control of the PRCA.

Female↗
PubMed1992

Hematopoietic progenitor cells in a patient with myeloid metaplasia without myelofibrosis.

A rare case of myeloid metaplasia without myelofibrosis is presented. Findings that the increase in blood megakaryocyte progenitor cells was not as prominent as the increase in granulocyte-monocyte and erythroid progenitor cells, and that the increase in bone marrow megakaryocytes was only slight might explain the absence of bone marrow fibrosis in this case. However, it is not clear whether the disease is a subtype or merely an early stage of myelofibrosis with myeloid metaplasia.

Aged↗
PubMed1991

Calmodulin-dependent protein phosphatase from Neurospora crassa. Molecular cloning and expression of recombinant catalytic subunit.

A cDNA for the catalytic subunit of a calmodulin (CaM)-dependent protein phosphatase was cloned from Neurospora crassa. The open reading frame of 1557 base pairs encoded a protein of Mr approximately 59,580 and was followed by a 3'-untranslated region of 363 base pairs including the poly(A) tail. Based on primer extension analysis, the mRNA transcript in vivo was 2403 base pairs. Expression of this CaM-protein phosphatase mRNA was developmentally regulated, being highest during early mycelial growth; production of the corresponding protein followed mRNA with a time lag of 8-12 h. Polymerase chain reaction amplification of genomic DNA revealed three small introns, the positions of which coincided with those in the mouse gene, indicating evolutionary conservation of these structures. The deduced sequence showed approximately 75% identity with the mammalian homologue, calcineurin, in aligned regions. A region of 40 amino acids preceding the CaM-binding domain was essentially unchanged, suggesting conservation of a crucial interaction site. Three small segments in the carboxyl half of the protein were unrelated to the mammalian gene and may constitute "variable regions" that confer substrate specificity to the enzyme. An active recombinant catalytic subunit was expressed in bacteria and purified by CaM-Sepharose chromatography. This preparation was stimulated 2- 3-fold by CaM and showed a p-nitrophenol phosphatase activity equal to that of the bovine brain holoenzyme, although its dephosphorylation of phosphoprotein substrates was markedly different. These findings demonstrate that the catalytic subunit of this phosphatase can exhibit high activity in the absence of its intrinsic Ca(2+)-binding subunit.

Amino Acid Sequence↗
PubMed1991

Nonsecretion of myeloma protein in spite of an increase in tumor burden by chemotherapy.

A unique case of IgA kappa myeloma is presented. While the myeloma cells had secreted a large quantity of IgA kappa monoclonal protein, they were induced to stop secreting the monoclonal protein by cyclophosphamide and vincristine, in spite of a remarkable increase in tumor burden. The absence of intracytoplasmic IgA kappa was clearly evidenced by the immunofluorescence technique using anti-IgA and anti-kappa monoclonal antibodies.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

[Changes in the blood cell counts with aging].

We analyzed the blood cell counts and serum levels of total protein (TP), total cholesterol (TC) and triglyceride (TG) of 2,231 healthy subjects (1,295 men and 936 women) between age 20 and 99 years in order to clarify the following two subjects. (1) In the approximately 10 years since the report of Shirakura et al in 1978, eating habits have improved and the average life expectancy has extended in Japan. Is there any effect of such betterment on blood cell counts of the aged? (2) It has been pointed out that quality of everyday life, such as staying at home but not in an old-age home, working, traveling, and so forth, had an influence on the blood cell counts of aged. Is there any difference between the blood cell counts of people under 60 years and those of people older than 60 years who have a good quality of life as mentioned above? The hemoglobin concentration, red blood cell count, and hematocrit value began to decrease in men in their sixth decade and in women in their seventh decade and the change was more prominent with advancing age, especially in men. The white blood cell count and platelet count tended to decrease with advancing age. The serum levels of TP, TC, and TG also declined with age in those over 60 years of age. These results confirmed that the hemoglobin concentration, red blood cell count, and hematocrit value decrease in the elderly subjects as they grow older and it may be considered that reduced ingestion of protein is one of the causes of the phenomenon.

Adult↗
PubMed1991

Three cases of multiple myeloma developing into melphalan-related chronic myelomonocytic leukemia.

From 1980 to 1987, three cases of chronic myelomonocytic leukemia (CMML) were encountered among 68 cases of multiple myeloma who survived more than three years from the diagnosis. The incidence (4.8%) of secondary myelodysplastic syndrome (MDS) is almost identical to previous reports, but case reports of chronic myelomonocytic leukemia were rare. In Japan, there are few reports of multiple myeloma patients who later developed secondary MDS or acute myelogenous leukemia (AML). In our cases, none of the 31 patients treated with cyclophosphamide developed secondary MDS, while three of 37 patients treated with melphalan developed CMML. This difference is not statistically significant.

Aged↗
PubMed1991

A patient with primary plasma cell leukemia accompanied by an extensive polypoid infiltration of the gastrointestinal tract.

A 37-year-old male presented with primary plasma cell leukemia (PCL) with kappa-type Bence Jones proteinuria (BJP) and polyposis of the stomach and colon. His plasma cell leukemia was not preceded by a pre-existing multiple myeloma, and presented the complication of polyposis in both stomach and colon. Biopsy of mucosal lesions revealed marked accumulation of atypical plasma cells with positive cytoplasmic kappa-chain. No amyloidosis was present. His disease responded remarkably well to intermittent melphalan and prednisolone. This case represents an uncommon combination of primary plasma cell leukemia and polypoid gastrointestinal lesions with plasma cell infiltration.

Adult↗
PubMed1991

Relief of severe diabetic truncal pain with mexiletine.

A 60 year-old Japanese man having a 20-year history of diabetes mellitus presented with truncal neuropathy. The severe pain, especially its nocturnal exacerbation, prevented him from sleeping and eating, resulting in rapid emaciation. However, he recovered from the condition with oral mexiletine, which dramatically controlled the pain.

Back Pain↗
PubMed1991

Studies by pancreatography of ductal changes induced by administration of pancreatic carcinogen in two dogs.

To assess the temporal changes of the pancreatic duct following the administration of N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) in two dogs, serial pancreatography was performed. They received intraductal administration of a total of 595 and 500 mg ENNG in each one, over the periods of 12 and 13.5 months, respectively. In one dog, sequential changes of the main duct were observed, a small round filling defect developed a circumferential defect and became a severe stenosis associated with proximal dilatation of the duct. While no gross tumors were macroscopically detected at autopsy, continuous lesions with features of hyperplasia, atypical hyperplasia, and cancerous change of duct epithelial cells were microscopically seen. In the other one, a small round filling defect was detected by pancreatography, which was histopathologically hyperplasia of pancreatic duct, rather than cancerous cells. The present dog model for induction of pancreatic duct carcinomas appears useful for elucidating clinico-pathological changes occurring during cancer development.

Adenocarcinoma↗
PubMed1990

Cloning and characterization of molecular isoforms of the catalytic subunit of calcineurin using nonisotopic methods.

The cloning and characterization of cDNAs for the catalytic subunit of calcineurin (CN) from murine and human brain libraries were carried out using nonisotopic methods. A murine cDNA clone encoding a protein of 521 amino acids (Mr approximately 58,650) was isolated; overlapping clones established a 3'-untranslated region of 554 base pairs preceding the poly(A) tail. Homologous cDNAs from human brain showed greater than 92% nucleotide sequence identity in both coding and non-coding regions with greater than 99% conservation of amino acid sequence. A second class of cDNAs lacking a specific 30-base pair region following the calmodulin-binding domain was found in four murine and human libraries. Oligonucleotide probes for both cDNA isoforms hybridized to mRNA from several brain regions indicating the existence of transcripts in vivo. The nucleotide sequences of the two forms were identical except for the inserted sequence, and Southern blot analysis of mouse and rat DNA was consistent with their having originated from the same gene; these data suggest that alternative splicing may give rise to molecular isoforms of the catalytic subunit in brain. Northern blots showed a predominant mRNA for CN in most tissues of approximately 4.0 kilobases (kb) with lower amounts of a 3.6-kb species. Brain showed 10 times more of these mRNAs than skeletal muscle while other tissues had less than or equal to 5% that in brain. In testis, multiple mRNAs were observed, with the major forms being approximately 2.8 and 1.6 kb; the total amount of CN message was about 15% that in brain. The presence of mRNA isoforms of the catalytic subunit may provide for isoenzymes of this phosphatase having distinct phosphoprotein substrate specificities or regulatory properties. The structural relatedness of CN to other mammalian serine/threonine protein phosphatases was highest over a region of approximately 240 amino acids near the amino terminus of this subunit, with greater similarity to protein phosphatase 2A than protein phosphatase 1. The conservation of many regions found in lambda phage phosphatase (Cohen, P.T.W., and Cohen, P. (1989) Biochem. J. 260, 931-934) indicates a common origin for the catalytic domain of this enzyme.

Amino Acid Sequence↗
PubMed1990

[An attempt to treat esophageal cancer by intraoperative local administration of oil bleomycin].

Intraoperative local chemotherapy was performed on patients with esophageal cancer, using oil bleomycin (oil BLM). Oil BLM was injected into the muscular layer of the thoracic esophagus to be resected, 2 ml (30 mg of BLM base) each near the anal and oral stumps of the esophagus. BLM concentrations in the regional lymph nodes which were determined were elevated, and the tumor tissue of the esophagus also showed high levels. The evidence has been recognized in this study that oil BLM which features lymphogenous transport and tissue accumulation spreads fast in the entire esophageal wall and is transported to and retained in the regional lymph nodes. Side effects from local administration of oil BLM or recurrence of cancer has not so far been observed. Judging from the results of this study, intraoperative local administration of oil BLM seems to be effective for adjuvant chemotherapy.

Bleomycin↗