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Biomedical subjects

K Tani

Publications and source records attributed to K Tani.

At least 307 records · Page 17Linked to original sources
PubMed1988

A new glucose-6-phosphate dehydrogenase variant (G6PD Tsukui) associated with congenital hemolytic anemia.

A new glucose-6-phosphate dehydrogenase (G6PD) variant associated with chronic nonspherocytic hemolytic anemia was found in a 20-year-old Japanese male who showed mild hemolysis after an upper respiratory tract infection. The patient had been noted to have jaundice and reticulocytosis several times before this episode. The enzyme activity of the variant was 1.5% of normal. The enzymatic characteristics were slow anodal electrophoretic mobility, high Km G6P, normal Km NADP, decreased heat stability, and a normal pH optimum. From these results, the enzyme was considered to be a new class 1 variant and was designated G6PD Tsukui.

Adult↗
PubMed1988

Expression of L- and M-type pyruvate kinase in human tissues.

Pyruvate kinase (PK) has four isozymes (L, R, M1, M2) that are encoded by two different genes of PK L and M. Differential splicing produces L- and R-type PK mRNA and M1- and M2-type PK mRNA from the PK L gene and the PK M gene, respectively. The nucleotide sequences of the 3'-noncoding region are the same between the L- and the R-type PK and between the M1- and the M2-type PK. We isolated 3'-noncoding sequences of human L- and M2-type PK cDNA to construct L-type and M-type PK specific probes. With these probes, we performed Northern blot analysis of the RNA samples extracted from human tissues. Northern blot analysis showed that both kidney and liver had mRNAs that hybridized with both the L and M probes. Small intestine, skeletal muscle, brain, testis, and lung mRNAs hybridized only with the M probe. Our probes are considered useful for the detection of the types of PK isozymes expressed in small amounts, which are very difficult to detect using the conventional PK polyacrylamide gel electrophoretic method.

DNA Restriction Enzymes↗
PubMed1988

Human liver type pyruvate kinase: complete amino acid sequence and the expression in mammalian cells.

Pyruvate kinase (PK) has four isozymes (L, R, M1, M2) that are encoded by two different genes. Among these isozymes, abnormalities of liver (L)-type PK is considered to be associated with hereditary nonspherocytic hemolytic anemia in humans. We isolated and determined the full-length sequence of human L-type PK cDNA. The cDNA contains 1629 base pairs encoding 543 amino acids, 68 base pairs of 5'-noncoding sequence, and 734 base pairs of 3'-noncoding sequence. The similarity between human and rat L-type PK was 86.9% at the nucleotide sequence level and 92.4% at the amino acid sequence level. The full-length L-type PK cDNA was placed under the promoter of simian virus 40 and introduced into monkey COS cells. Human L-type PK activity was detected in the extract of COS cells by the classical PK electrophoresis method.

Amino Acid Sequence↗
PubMed1988

Immunological detection of 22K protein in sporulating cells of Bacillus megaterium ATCC 12872.

The synthesis and deposition of 22,000-dalton (22K) spore coat protein were examined immunochemically on the sporulating cells of Bacillus megaterium ATCC 12872 using the antibody to purified 22K spore coat protein. This antibody cross-reacted with 44K and 25K proteins in immunoblot analysis of dormant spore coat proteins. Immunoblot analysis on the sporulating cells showed that 22K protein was detected from t8 in forespore coat protein fractions. Sandwich enzyme immunoassay revealed that 22K protein in the spore coat protein fraction appeared at t6 and reached a plateau at t9, and 22K protein in the mother cell cytoplasmic fraction was detected at only t7 and t8 at a very low level.

Bacillus megaterium↗
PubMed1988

Molecular analysis of Lesch-Nyhan syndrome found in Japan.

Molecular analysis of four unrelated patients with Lesch-Nyhan (L-N) syndrome was performed. All four cases had typical clinical features of L-N syndrome, and the activities of hypoxanthine-guanine phosphoribosyltransferase (HPRT) were absent. No structural gene abnormalities were found by Southern blot analysis in all cases, and a decrease of HPRT mRNA was not detected by dot blot analysis in two of the four cases. However, HPRT enzyme proteins were detected by Western blot analysis in all cases. Our results showed that the production of immunologically reactive but enzymatically inactive mutant HPRT protein was pathogenic for all four patients.

Adult↗
PubMed1988

[A study on the bactericidal action of aspoxicillin against Escherichia coli].

In an attempt to clarify the role of a side chain, N4-methyl-D-asparagine, of aspoxicillin (ASPC) in the antibacterial action, we examined the bactericidal activity of dehydroxyaspoxicillin (AB-ASPC) and its affinity for the penicillin-binding proteins (PBPs) of Escherichia coli using piperacillin (PIPC), mezlocillin (MZPC) and apalcillin (APPC) as the reference penicillins. ASPC and AB-ASPC showed high bactericidal activities against E. coli K-12 even when a large inoculum size (2 x 10(8) CFU/ml) was used. The observation of these cultures with a phase contrast microscope revealed that E. coli cells lysed after the formation of spheroplast-like or bulged structures. On the other hand, PIPC, MZPC and APPC converted the cells to long filaments, but did not show lytic action in the range of the concentrations used. These morphological changes were also observed with a scanning electron microscope. Superior bacteriolytic activities of ASPC and AB-ASPC were further shown by measuring 'triggering' autolytic activity by the penicillins. The release of labeled murein from E. coli chi 1776 after the exposure to ASPC or AB-ASPC was clearly greater than those caused by the reference penicillins. ASPC showed affinity for PBPs of E. coli K-12, 1A, 1Bs, 2 and 3, and its affinity pattern resembled the one obtained with ampicillin (ABPC). AB-ASPC behaved in a fashion similar to ASPC, although its affinities for PBP 1A and 1Bs were lower and that for PBP 3 was slightly higher. These observations suggest that the highest bactericidal activity of ASPC against E. coli with lysis among the acyl-ureidopenicillins tested is due to N4-methyl-D-asparagine in the side chain of ASPC.

Amoxicillin↗
PubMed1988

Adenosine deaminase (ADA) overproduction associated with congenital hemolytic anemia: case report and molecular analysis.

We report the fourth case of adenosine deaminase (ADA) overproduction associated with hereditary nonspherocytic hemolytic anemia and the molecular analysis of this anomaly. The proband was a 10-year-old Japanese boy, who had an episode of erythroblastosis fetalis during the perinatal period. The red cell ADA activity showed a 110-fold increase and the red cell ATP level was about 64% of the comparably reticulocyte-rich controls, but the lymphocyte ADA activity was within the normal range. Western blotting of partially purified ADA from red cells revealed an increased amount of enzyme in the patient's red cells. No gene amplification or gene rearrangement was found by Southern blot analysis, and no increase of ADA mRNA in reticulocyte RNA was detected by dot blot analysis using ADA cDNA. We constructed a genomic DNA library and obtained three clones containing the 5'-promoter region of ADA gene. The 2.2 kb ADA promoter DNA fragment of these clones was fused to the chloramphenicol acetyl transferase (CAT) gene, and transfected to human erythroid cell line K562, and assayed for CAT activity. One of the clones, pADOP 2 cat, expressed about 2.6 times higher CAT activity than the normal ADA promoter fused to CAT gene in K562, but such enhancement was not seen in human non-erythroid cell lines; HL 60 and Raji. From these results, it is most likely, though not conclusive, that the 5' promotor fragment of the ADA gene of the patient was responsible for the cell-specific enhancement of protein synthesis.

Adenosine Deaminase↗
PubMed1988

The role of autoreactive T-cell hybridomas from autoimmune model mice.

Autoreactive IL-2-producing T-cell hybridomas were established from New Zealand Black and White (B/W) F1 and MRL/1 mice. In B/WF1 mice the frequency of IL-2-producing hybridomas increased with age. It is necessary for the cells to recognize autologous MHC molecules in order to release IL-2. Inoculation of hybridoma cells into several mouse strains via the footpad produced significant swelling responses in an H-2-restricted manner. Finally, several autoimmune abnormalities were induced in naive H-2-compatible mice by i.v. inoculation of certain hybridoma cells. These results demonstrate that self-MHC molecule recognition by T cells plays an important role in the development of autoimmunity.

Aging↗
PubMed1988

Chylothorax and chylous ascites in a patient with uterine cancer.

A 63-year-old woman, who had undergone radical hysterectomy and radiation therapy for cervical cancer of the uterus three years previously, was found to have pleural effusion and ascites. A diagnosis of chylothorax and chylous ascites was made on the basis of these fluids' characteristics. She received medium-chain triglyceride (MCT) in her diet and intra-venous hyperalimentation to decrease the leakages of chyle into the pleural and peritoneal cavities, but she died of respiratory and renal failures after six months. At autopsy, metastases from the cervical cancer of the uterus to the lymph nodes in the mediastinum and around the abdominal aorta were proved histologically. Lymph node swelling due to metastasis had caused a rupture of the thoracic duct, leading to chylothorax and chylous ascites. The diagnosis, evaluation and therapeutic modalities of the condition are outlined and the literature reviewed.

Carcinoma, Squamous Cell↗