Biomedical subjects
H Taguchi
Publications and source records attributed to H Taguchi.
IgD myeloma presenting as a testicular tumor: establishment and characterization of an IgD-secreting myeloma cell line.
A 72-year-old man presented with a left testicular tumor and underwent orchiectomy. The tumor was massively infiltrated with myeloma cells bearing monoclonal cytoplasmic IgD lambda. Three months after orchiectomy, he developed huge abdominal masses and subsequently ascites containing numerous myeloma cells. An IgD-secreting myeloma cell line, designated delta-47, was established from the ascites. This cell line expressed CD4 and CD38, but lacked Fc and complement receptors, surface immunoglobulin, CD19, HLA-DR, and PCA-1. CD30 was detected on the cultured cells but not on the ascites tumor cells. Delta-47 cells secreted the same immunoglobulin (IgD lambda) as was found in the patient's serum. The light chain had a molecular weight of 35 kD which was larger than that of the normal light chain. Chromosome analysis of delta-47 revealed an aneuploid karyotype with complex abnormalities including 1q+, 2p+, and 14q+. To our knowledge, this is the only IgD-secreting myeloma cell line and would provide a useful tool for the study of IgD production and IgD myeloma.
Survival rates of some terrestrial microorganisms under simulated space conditions.
In connection with planetary quarantine, we have been studying the survival rates of nine species of terrestrial microorganisms (viruses, bacteria, yeasts, fungi, etc.) under simulated interstellar conditions. If common terrestrial microorganisms cannot survive in space even for short periods, we can greatly reduce expenditure for sterilizing space probes. The interstellar environment in the solar system has been simulated by low temperature, high vacuum (77 k, 4 x 10(-6) torr), and protons irradiation from a Van de Graaff generator. After exposure to a barrage of protons corresponding to about 250 years of irradiation in solar space, Tobacco mosaic virus, Bacillus subtilis spores, Aspergillus niger spores and Clostridiun mangenoti spores showed survival rates of 82%, 45%, 28%, and 25%, respectively. Furthermore. pathogenic Candida albicans showed 7% survival after irradiation corresponding to about 60 years in space.
Effects of verapamil on histamine-induced changes in lung mechanics.
The effects of verapamil on airway resistance and total thoracic compliance were studied in 15 rabbits with histamine-induced changes in lung mechanics. The animals, after being tracheotomized under anaesthesia, were subjected to mechanical ventilation in a time-cycled, volume-limited mode. Airway pressure and gas flow signals measured by a pneumotachograph and integrated for volume, were registered on a recorder. Each animal was given histamine hydrochloride in an isotonic solution of sodium chloride at a rate of 0.05 micrograms.kg-1.min-1 through a peripheral venous line. Verapamil was infused intravenously in an isotonic solution of sodium chloride at a rate of 20 micrograms.kg-1.min-1 after the initiation of histamine. Verapamil reduced the histamine-induced increase in airway resistance by 20% at 20 min after the start of administration.
Epitope homology between bacterial heat shock protein and self-proteins in the host cell.
Mouse monoclonal antibodies (MAbs) showing distinct reactivity against the 60-kilodalton (kDa) antigen heat shock protein of Yersinia enterocolitica, designated cross-reacting protein antigen (CRPA), have previously been established. The reactivities of these MAbs (5C3 and 3C8) against mouse and human host cells were studied by Western blotting and flow cytometric analysis. The results indicated that epitopes on the bacterial 60-kDa heat shock protein are present on various molecules in mouse spleen cells and human B cells. An epitope recognized by MAb 5C3 was expressed on the mouse and human host cell surface, and an epitope recognized by MAb 3C8 was also expressed on the human host cell surface.
[Studies on the effect of combination of amphotericin B and flucytosine on Candida albicans by flow cytometry].
The antifungal effects of amphotericin B (AMPH) and flucytosine (5-FC) on three strains of Candida albicans were studied by flow cytometry (FCM). When the IFM4954 and IFM4949 were treated with AMPH or 5-FC alone, cytograms of cell distribution changed at the concentration of 1/2 MIC, respectively. Next, the effect of combination of AMPH and 5-FC were examined. Cytogram of cell distribution of IFM4954 and IFM4949 changed under the combination of 1/4 MIC of AMPH and 1/4 MIC of 5-FC, namely a synergic effect was observed. In conclusion, FCM is a useful apparatus for analysis of the effect of antifungal agents.
Blood pressure response to hyperinsulinemia in salt-sensitive and salt-resistant rats.
We investigated the role of insulin in salt-sensitive hypertension in Dahl salt-sensitive and salt-resistant rats. The rats were kept in metabolic cages, and sodium intake and urinary sodium excretion were measured. In salt-sensitive rats receiving a 0.3% NaCl diet, sodium retention was significantly greater at weeks 1 and 2 in rats that received an insulin infusion than in those receiving a saline infusion. Mean arterial blood pressure and plasma norepinephrine levels were significantly higher at week 3 in insulin-treated rats than in saline-treated rats (mean arterial pressure, 137 +/- 3 mm Hg versus 119 +/- 3 mm Hg, p < 0.05; plasma norepinephrine, 0.40 +/- 0.02 ng/ml versus 0.27 +/- 0.01 ng/ml, p < 0.05). Insulin did not influence sodium retention, mean arterial pressure, or plasma norepinephrine in salt-resistant rats. Coadministration of an alpha-blocker (bunazosin, 10 mg/kg per day for 3 weeks) in salt-sensitive rats abolished the insulin-induced elevations in mean arterial pressure and sodium retention. When salt-sensitive rats were fed a low salt diet (0.03% NaCl), insulin did not raise mean arterial pressure. Thus, insulin elevated blood pressure only in the salt-sensitive model. The sympathetic nervous system and sodium retention in the early phase of insulin overload may contribute to elevation of mean arterial pressure in this model.
Purification and characterization of a thermostable carboxypeptidase (carboxypeptidase Taq) from Thermus aquaticus YT-1.
A thermostable carboxypeptidase, which we named carboxypeptidase Taq, was purified from Thermus aquaticus YT-1 and characterized. The molecular weight of the enzyme was estimated to be about 56,000 and 58,000 on SDS-polyacrylamide gel electrophoresis and gel filtration, respectively, indicating that the enzyme has a monomeric structure. The optimum pH of the enzyme was 8.0, and the optimum temperature for the reaction was 80 degrees C. The enzyme activity was dependent on cobalt ion and was inhibited by metal-chelating reagents, indicating that the enzyme is a metalloenzyme. The enzyme had high thermostability independent of cobalt ion; about 90% of its activity remained even after treatment at 80 degrees C for 5 h. The enzyme showed broad substrate specificity, although proline at the C-terminus of peptides was not cleaved. The enzyme released amino acids sequentially from the C-terminus.
Cryptococcal pleural effusion in an HTLV-I carrier with Waldenstroem's macroglobulinemia.
A 70-year-old woman with Waldenstroem's macroglobulinemia developed bilateral pleural effusions due to Cryptococcus neoformans. She was found to be a carrier of HTLV-I. It is speculated that the opportunistic infection occurred as the result of an impaired cellular immunity secondary to HTLV-I infection.
Immunohistochemical detection of Pneumocystis carinii in transbronchial lung biopsy specimens: antigen difference between human and rat Pneumocystis carinii.
Transbronchial lung biopsy specimens, from three patients with non-AIDS-related Pneumocystis carinii pneumonia (PCP) and rat lung tissue in which PCP was induced by the administration of dexamethasone, were studied to determine the diagnostic usefulness of an immunohistochemical method using commercially available anti-Pneumocystis monoclonal antibody, 3F6, on formalin-fixed, paraffin-embedded tissue. PC was consistently stained a bright red color and unambiguously identified in all three human lung specimens, but not stained in lung tissues at autopsy from patients with various fungal pneumonias. In contrast, PC was weakly stained in PCP-induced rat lungs. The present study indicates human PC and rat PC to be antigenically different in terms of the existence of the 82 kilo-dalton (kD) antigen against which 3F6 is directed.
[Three cases of chronic respiratory tract lesions associated with adult T-cell leukemia (ATL)].
Three cases of chronic respiratory tract lesions as a complication of adult T-cell leukemia (ATL) are reported. Case 1 was seropositive for HTLV-1 on recent examination following treatment of bronchiolitis. Chest radiograph revealed over inflation of the lungs and bilateral diffuse small nodular shadows. Pulmonary function test resulted hypoxemia and mixed ventilation disorder. Pathological examination confirmed lymphocytic infiltration of the bronchiolar wall. Both clinically and pathologically the patient was diagnosed as having diffuse panbronchiolitis (DPB). Therefore, this case was considered to be the bronchiolar type of HTLV-1 associated bronchiolo-alveolar disorder (HABA). The other two cases with smoldering or chronic ATL presented with long-standing symptoms of productive cough due to chronic respiratory lesions. We consider that all three cases had HTLV-1 virus associated pulmonary lesions, but with different clinical and pathological presentations. Among 12 cases of bronchiolitis experienced at our hospital, three were positive for HTLV-1.
[A case of renal cell carcinoma with lung metastasis and local recurrence effectively treated with nephrectomy and UFT].
A 74-year-old woman was admitted on July 18, 1989 for an abnormality on her chest roentgenogram. Right renal tumor with bilateral pulmonary metastasis was detected and right nephrectomy was performed. Because of the progression of pulmonary metastasis and the local recurrence after surgery, UFT was orally administered at a dose of 300 mg everyday since Dec. 12, 1989. The chest roentgenogram on Nov. 21, 1990 showed progression of lung lesions. But at the 20 th month after the beginning of chemotherapy, both lung lesions disappeared completely and local recurrence around the operative wound strikingly improved. This is a rare case of renal cell carcinoma with local recurrence and lung metastasis successfully treated with UFT.
[Intensive induction chemotherapy of adult acute myelogenous leukemia by continuing daunorubicin, behenoyl-cytosine arabinoside, 6-mercaptopurine and prednisolone until marrow aplasia].
Intensive induction chemotherapy was applied to 25 patients with acute myelogenous leukemia by continuing drugs (daunorubicin, behenoyl-cytosine arabinoside, 6-mercaptopurine and prednisolone) until the achievement of severe bone marrow aplasia (leukemic cells less than 1,000/microliters). Complete remission (CR) was achieved in 18 (72%). Numbers of partial remission and an early death were 5 (20%) and 2 (8%), respectively. Although median nadirs of white blood cells (WBC) and platelet counts (Pl) (205/microliters and 8,200/microliters, respectively) were remarkably low, recovery of WBC (over 1,000/microliters) and Pl (over 50,000/microliters) were achieved in 23.8 and 24.5 days, after an initiation of the chemotherapy. Sepsis was a most frequently observed complication during induction stage and a duration of fever was 2-48 days (median 15). Median duration of CR was 22.9 months. Unexpectedly, 11 of 17 CR (except one with bone marrow transplanted) relapsed after 4.2-41.4 months (median; 9.4), but 6 (35.3%) still remain in first CR for 30.5-72.9 months (median; 51.4). A long-term survival might be obtained by intensifying induction chemotherapy in about one fourth of patients, but the intensification or application of non-cross resistant anti-leukemic agents in post-remission therapy may be required to avoid relapses even if induction is intensified.
[The clinical significance of eosinophils in urine].
The clinical significance of eosinophils in urine was examined. Eosinophils were found in 9 out of 10 cases of interstitial cystitis, and there were more than 50 eosinophils in 50 fields in 6 of these cases. Although the number of eosinophils almost correlated with the number of leucocytes, the relationship between eosinophils and leucocytes in interstitial cystitis was different in acute and chronic cystitis. Since urinary eosinophils could be observed in cases of interstitial cystitis in which leucocytes were as low as 3 to 10 per field and the number of eosinophils was not decreased by chemotherapy, the urinary eosinophils in interstitial cystitis may be of allergic significance and reflect eosinophilic infiltration into the bladder wall.
Acute megakaryoblastic leukemia: establishment of a new cell line (MKPL-1) in vitro and in vivo.
A megakaryoblastic cell line (MKPL-1) was newly established from the bone marrow of an adult patient with acute megakaryoblastic leukemia. This cell line grew in single cell suspension with a doubling time of 30 h and consisted of large primitive blasts with persistent development of giant cells carrying multilobed nuclei. MKPL-1 cells were positive for platelet GPIIb/IIIa (CD41) and GPIIIa (CD61), and expressed OKM5 (CD36), MY7 (CD13), and MY9 (CD33) antigens in the absence of erythroid and lymphoid markers. The cytochemical and morphologic characteristics of MKPL-1 were also consistent with those of megakaryoblasts. The cells did not, however, express ultrastructural platelet peroxidase which is considered to be another marker of the megakaryocytic lineage. Cytogenetic analysis of MKPL-1 revealed a model chromosome number of 92 with abnormal chromosomes including those found in the patient's bone marrow cells. Furthermore, MKPL-1 cells were serially transplanted into nude mice for nine passages with production of lethal tumors and leukemic manifestation. Thus, our megakaryoblastic cell line which can be maintained both in vitro and in vivo would be useful for further studies of the biology of megakaryopoiesis and megakaryoblastic leukemia.
[Post-gastrectomized vitamin B12 deficient anemia with marked leukoerythroblastosis and ringed sideroblasts].
A 77 year-old man, who had received total gastrectomy and splenectomy 11 years ago for gastric cancer was transferred to our hospital because of severe macrocytic anemia. He had been treated with vitamin B1, B2, C and iron preparations for several weeks. Ten days before admission numbness developed in his legs. On physical examination he appeared severely anemic. Laboratory findings revealed severe macrocytic anemia with poikilocytosis, anisocytosis, polychromasia, red cell fragmentation, Howell-Jolly bodies, Cabot rings and marked erythroblastosis (421/100 WBC). Hypersegmented neutrophils and immature granulocytes were also seen in the blood. The bone marrow picture showed marked erythroid hyperplasia, but erythroblasts revealed only slight megaloblastic changes. On bone marrow iron staining all erythroblasts were classified as type III sideroblasts and 15% of them were ringed-form. Serum vitamin B12 was low (44 pg/ml). Methylcobalamin given intramuscularly led to the rapid improvement of all hematological abnormalities including leukoerythroblastosis. Two weeks after vitamin B12 administration, ringed sideroblasts could no longer be detected in the bone marrow. Post-gastrectomy vitamin B12 deficiency anemias combined with erythroblastosis and ringed sideroblasts is a rare condition. Splenectomy is thought to play an important role in the pathogenesis of these conditions.
A chaperonin from a thermophilic bacterium, Thermus thermophilus, that controls refoldings of several thermophilic enzymes.
A chaperonin has been purified from a thermophilic bacterium, Thermus thermophilus. It consists of two kinds of proteins with approximate Mr 58,000 and 10,000 and shows a 7-fold rotational symmetry from the top view and a "football"-like shape from the side view under the electron microscopic view. Its weak ATPase activity is inhibited by sulfite and activated by bicarbonate. ATP causes change of its mobility in nondenaturating polyacrylamide gel electrophoresis. The T. thermophilus chaperonin can promote in vitro refolding of several guanidine HCl-denatured enzymes from thermophilic bacteria. At high temperatures above 60 degrees C, where the native enzymes are stable but their spontaneous refoldings upon dilution of guanidine HCl fail, the chaperonin induces productive refolding in an ATP-dependent manner. No or very poor refolding is induced when the chaperonin is added to the solution aged after dilution. An excess amount of the chaperonin is inhibitory for refolding. At middle temperatures (30-50 degrees C), where spontaneous refoldings of the enzymes occur, the chaperonin arrests refolding in the absence of ATP and refolding is induced when ATP is supplemented. At temperatures below 20 degrees C, where spontaneous refoldings also occur, the chaperonin arrests the refolding but ATP does not induce refolding.
Structural organization of the pigment cell-specific gene located at the brown locus in mouse. Its promoter activity and alternatively spliced transcript.
The pigment cell-specific gene, located at the brown (b) locus in mouse, has been cloned and characterized. Its gene product is required for the formation of black melanin rather than brown, although its exact function remains to be elucidated. We thus tentatively named it b-locus protein in this report. The b-locus protein gene is about 18 kilobase pairs long and organized into 8 exons and 7 introns. Functional analysis of its promoter region suggests that the nucleotide residues -38/154 is sufficient to direct the pigment cell-specific transcription in melanoma whole cell extracts. On the other hand, we were unable to detect its transcripts in HeLa whole cell extracts. Sequence comparison with the promoter region of the tyrosinase gene, another pigment cell-specific gene, reveals that two elements of the b-locus protein gene (-33/-24 and 18/28) are also conserved in the tyrosinase gene at equivalent positions, suggesting that these two elements may be involved in their pigment cell-specific transcription. Furthermore, we have cloned a cDNA, pMT3, coding for an isoform of b-locus protein from a cDNA library of mouse B16 melanoma cells. Sequence analysis of pMT3 reveals a deletion of 103 base pairs, which corresponds to the 5'-end of the exon 8 of the b-locus protein gene, indicating that pMT3 represents a mRNA species generated by alternative splicing. Since this deletion changes the reading frame and eliminates the transmembrane domain of b-locus protein, the pMT3-type mRNA may code for a soluble isoform. Such an isoform, consisting of 553 amino acids, differs only in its carboxyl terminus and is larger than b-locus protein by 16 amino acids. Using transient expression assays, we confirmed that such an isoform is able to react with anti-b-locus protein monoclonal antibody, TMH-1, suggesting that a b-locus protein isoform may have some function in pigmentation.