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K Kuma

Publications and source records attributed to K Kuma.

At least 109 records · Page 6Linked to original sources
PubMed1994

Phylogenetic relationship of the kingdoms Animalia, Plantae, and Fungi, inferred from 23 different protein species.

The phylogenetic relationship among the kingdoms Animalia, Plantae, and Fungi remains uncertain, because of lack of solid fossil evidence. In spite of the extensive molecular phylogenetic analyses since the early report, this problem is a longstanding controversy; the proposed phylogenetic relationships differ for different authors, depending on the molecules and methods that they use. To settle this problem, we have accumulated 23 different protein species from the three kingdoms and have inferred the phylogenetic trees by three different methods--the maximum-likelihood method, the neighbor-joining method, and the maximum-parsimony method--for each data set. Although inferred tree topologies differ for different protein species and methods used, both the maximum-likelihood analysis based on the difference (delta l) between the total log-likelihood of a tree and that of the maximum-likelihood tree and bootstrap probability (P) of 23 proteins consisting of 10,051 amino acid sites in total have shown that a tree ((A,F),P), in which Plantae (P) is an outgroup to an Animalia (A)-Fungi (F) clade, is the maximum-likelihood tree; the delta l (= 0.0) and P (94%) of ((A,F),P) are significantly larger than those of ((A,P),F) (delta l = -54.4 +/- 36.3; and P = 6%) and ((F,P),A) (delta l = -141.1 +/- 30.9; and P = 0%).(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Population Groups↗
PubMed1994

Immunological findings and thyroid function of untreated Graves' disease patients with undetectable TSH-binding inhibitor immunoglobulin.

OBJECTIVE: TSH-binding inhibitory immunoglobulin (TBII) is undetectable in about 10% of untreated Graves' disease patients, but the clinical characteristics and immunological significance of this finding are unknown. In this study we evaluated the clinical characteristics of TBII negative Graves' disease. PATIENTS: We examined TBII in 1048 untreated patients at Kuma hospital from 1986 to 1990 and found 69 TBII undetectable patients (12 men and 57 women, mean age +/- SEM 35 +/- 2 years, group A). MEASUREMENTS: We compared the clinical characteristics and immunological findings of group A with 57 untreated TBII detectable Graves' patients who were selected randomly (11 men and 46 women, mean age +/- SEM 40 +/- 2 years, group B). T4, TSH, FT4, FT3, 123I thyroid uptake, TBII, thyroid stimulating antibodies (TSAb) and the volume of the thyroid using ultrasonography were measured at the first visit. RESULTS: Serum T4, FT4 and FT3 levels in group A were significantly lower than those in group B (P < 0.001). The values of TSAb in group A were significantly lower than those in group B (593 +/- 67 (mean +/- SE) vs 2143 +/- 280%, respectively, P < 0.001). The 123I thyroid uptake in group A was significantly lower than that in group B (53.1 +/- 1.1 vs 61.4 +/- 1.4%, respectively, P < 0.01). The thyroid volume in group A was significantly smaller than that in group B (39.1 +/- 3.0 vs 51.3 +/- 3.3 ml, respectively, P < 0.01). TSAb was undetectable in about 10% (6) of the TBII negative untreated Graves' patients at their first visit. CONCLUSION: In the present study, untreated TBII negative patients with Graves' disease were characterized by mild elevation of thyroid hormones, mildly elevated 123I uptake, weak TSAb activities and small goitres. The finding of both TBII and TSAb negative titres in untreated Graves' disease patients was also confirmed.

Adult↗
PubMed1994

Crystal structures of synthetic 7 angstrom and 10 angstrom manganates substituted by mono- and divalent cations.

The crystal structures of synthetic 7 angstrom and 10 angstrom manganates, synthetic birnessite and buserite, substituted by mono- and divalent cations were investigated by X-ray and electron diffractions. The monoclinic unit cell parameters of the subcell of lithium 7 angstrom manganate, which is one of the best ordered manganates, were obtained by computing the X-ray powder diffraction data: a = 5.152 angstroms, b = 2.845 angstroms, c = 7.196 angstroms, beta = 103.08 degrees. On the basis of the indices obtained by computing the X-ray diffraction data of Li 7 angstrom manganate, monovalent Na, K and Cs and divalent Be, Sr and Ba 7 angstrom manganates were interpreted as the same monoclinic structure with beta = 100-103 degrees as that of Li 7 angstrom manganate, from their X-ray diffraction data. In addition, divalent Mg, Ca and Ni 10 angstrom manganates were also interpreted as the same monoclinic crystal system with beta=90-94 degrees. The unit cell parameters, especially a, c and beta change possibly with the type of substituent cation probably because of the different ionic radius, hydration energy and molar ratio of substituent cation to manganese. However, these diffraction data, except for those of Sr and Ba 7 angstrom and Ca and Ni 10 angstrom manganates, reveal only some parts of the host manganese structure with the edge-shared [MnO6] octahedral layer. On the other hand, one of the superlattice reflections observed in the electron diffractions was found in the X-ray diffraction lines for heavier divalent cations Sr and Ba 7 angstrom and Ca and Ni 10 angtrom manganates. The reflection presumably results from the substituent cation position in the interlayer which is associated with the vacancies in the edge-shared [MnO6] layer and indicates that the essential vacancies are linearly arranged parallel to the b-axis. Furthermore, the characteristic superlattice reflection patterns for several cations, Li, Mg, Ca, Sr, Ba and Ni, manganates were interpreted that the substituent cations are regularly distributed in the interlayer according to the exchange percentage of substituent cation to Na+. In contrast, the streaking in the a-direction observed strongly in the electron diffractions for heavier monovalent cations, K and Cs, manganates probably results from the disordering of their cations in the a-direction in the interlayer.

Cations↗
PubMed1994

Resistance to autoimmune thyroid disease is associated with HLA-DQ.

Genotypes of DQA1 and DQB1 genes were determined by polymerase chain reaction followed by dot blot hybridization with sequence-specific oligonucleotide probes in 105 patients with goitrous autoimmune thyroiditis (Hashimoto's thyroiditis) and in 67 patients with Graves' disease to investigate whether specific DQ alleles were associated with susceptibility or resistance to autoimmune thyroid diseases. Hashimoto's thyroiditis was found to be negatively associated with DQA1*0102 and DQB1*0602 whereas Graves' disease showed a negative association with DQB1*0501. No strongly positive association with a specific DQ allele was found in either disease. These results suggest that the HLA-DQ gene may be a genetic marker for resistance to autoimmune thyroid diseases.

Autoimmune Diseases↗
PubMed1994

A possible link between molecular evolution and tissue evolution demonstrated by tissue specific genes.

In this paper, we reviewed our recent works on a possible link between molecular evolution and tissue evolution. The evolutionary rates of genes that are expressed tissue specifically were shown to differ widely to one another, depending on tissues: Brain specific genes evolve with significantly slower rate than immune specific genes. The tissue dependence of molecular evolutionary rate strongly suggests the presence of functional constraints against molecular changes from tissue level. A molecular phylogenetic analysis of tissue specific isoforms that are identical to one another in function, but differ only in tissue distribution revealed frequent gene duplications and rapid accumulations of amino acid substitutions during the early evolution of chordates, where rapid evolution at the tissue or organ levels is thought to have occurred. On the basis of functional constraints, a possible explanation for the correlation between evolution at the two levels was presented.

Animals↗
PubMed1994

Mammalian phylogeny inferred from multiple protein data.

On the basis of multiple protein data, the phylogenetic relationships among the major clades of eutherian mammals, Primates, Cetacea, Artiodactyla, Carnivora, Lagomorpha, Myomorpha, and Caviomorpha, were analyzed by the maximum likelihood (ML) method, together with the maximum parsimony (MP) method and the neighbor joining (NJ) method. Using nineteen protein data, we first reexamined the hypothesis of rodent polyphyly proposed by Graur et al. (1991) based on the four taxon system, consisting of human, mouse (or rat), guinea-pig and an outgroup. The ML analysis does not support the rodent polyphyly, but strongly favors the traditional view of rodent monophyly representing the Myomorpha-Caviomorpha association. In the second analysis, the phylogenetic position of Lagomorpha were reexamined using three sets of multiple protein data, 13 mitochondrial DNA-coded proteins from rodents, rabbit, human, seals, bovine, whales and opossum, 25 protein data from human, rabbit and rodents and an outgroup, and 20 protein data from human, rabbit, bovine (or pig) and rodents. Our analysis favors the closer affinity of Lagomorpha to Primates than to Rodentia. The branching sequence of seven mammalian groups revealed by the present analyses is as follows: Myomorpha-Caviomorpha clade (Rodentia), rabbit, Primates, Carnivora, and Artiodactyla-Cetacea clade. Judging from the branch lengths measured by the numbers of synonymous substitutions, a series of divergence of these mammals is likely to be bush-like. The rapid rate of rodent evolution was reexamined in the light of the new phylogeny.

Amino Acid Sequence↗
PubMed1994

Cloning of the cDNA for a novel receptor tyrosine kinase, Sky, predominantly expressed in brain.

Based on homology to the tyrosine kinase domain of the chick erythroblastosis virus oncogene v-sea, we cloned a cDNA encoding a novel receptor tyrosine kinase from a human hepatoma HepG2 cDNA library. The encoded protein, which we termed 'Sky', contains an intracellular tyrosine kinase domain and a unique extracellular domain with two immunoglobulin (Ig)-like domains and two fibronectin type III (FN III) domains. The overall structure of Sky is homologous to the reported sequence of the oncogenic Axl/Ufo receptor tyrosine kinase. Phylogenetic analysis in the tyrosine kinase domain shows that Sky, Axl/Ufo, Ark, and v-Ryk form a sub-family distinct from other tyrosine kinases. Northern blot analysis revealed that sky mRNA is expressed predominantly in brain and faintly in tissues of other organs. As the combination of Ig-like and FN III domains is often observed in neural cell adhesion molecules and receptor protein tyrosine phosphatases, Sky may be involved in cell adhesion processes, particularly in the central nervous system.

Amino Acid Sequence↗
PubMed1994

Identification of a human cDNA encoding a novel protein kinase with two repeats of the LIM/double zinc finger motif.

By low-stringency screening of a human hepatoma HepG2 cell cDNA library, using the genomic fragment of chick c-sea receptor tyrosine kinase as a probe, we isolated overlapping cDNAs encoding a novel protein kinase, which we termed LIM-kinase (LIMK).* The predicted open reading frame encodes a 647-amino-acid polypeptide containing a putative protein kinase structure in the C-terminal half. In addition, LIMK has two repeats of cysteine-rich LIM/double zinc finger motif at the most N-terminus. To our knowledge, this is the first protein kinase seen to contain the LIM motif(s) in the molecule. Although the protein kinase domain of LIMK has highly conserved sequence elements of protein kinases, phylogenetic analysis revealed that LIMK cannot be classified into any subfamily of known protein kinases. Northern blot analysis revealed that the single species of LIMK mRNA of 3.3 kb was expressed in various human epithelial and hematopoietic cell lines. In rat tissues, LIMK mRNA was expressed in the brain, at the highest level. LIM is suggested to be involved in protein-protein interactions by binding to another LIM motif. As the LIM domain is frequently present in the homeodomain-containing transcriptional regulators and oncogenic nuclear proteins, LIMK may be involved in developmental or oncogenic processes through interactions with these LIM-containing proteins.

Amino Acid Sequence↗
PubMed1993

Rapidly progressive thyroid failure in Graves' disease after painful attack in the thyroid gland.

We studied a new type of Graves' disease: rapidly progressive thyroid failure after painful attack in the thyroid gland. Four women with the mean (+/- SD) age of 51 +/- 3.2 years had newly diagnosed hyperthyroid Graves' disease. A severe painful episode developed in the thyroid glands of two patients and permanent hypothyroidism occurred spontaneously within 2 or 3 months thereafter. Two to three episodes of pain developed in the thyroid glands of the other two patients during antithyroid drug therapy. There was a transient rise in serum thyrotropin level after each painful episode and permanent hypothyroidism developed 6 to 8 months after the initial painful attack. The clinical picture is characterized by moderate to severe pain in the thyroid gland with tenderness. Patients responded to steroid or anti-inflammatory therapy. During painful attack, increased or normal thyroid radioiodine uptake, elevated levels of C-reactive protein, and an elevated erythrocyte sedimentation rate were found, but there was no cytological evidence of subacute thyroiditis. After painful attack, serum thyroid stimulation antibody began to decrease in three of the patients while thyroid stimulation blocking antibody developed in one patient. This is a rapid and self-destructive process of the Graves' thyroid gland, which appears to be associated with painful attack in the thyroid gland.

Autoantibodies↗
PubMed1993

Limulus hemocyte transglutaminase. cDNA cloning, amino acid sequence, and tissue localization.

We have evidence that the limulus (Tachypleus tri-dentatus) hemocyte transglutaminase (TGase) has a molecular mass of 86 kDa and properties of the mammalian type II TGase-like enzyme (Tokunaga, F., Yamada, M., Miyata, T., Ding, Y.-L., Hiranaga-Kawabata, M., Muta, T., Iwanaga, S., Ichinose, A., and Davie, E.W. (1993) J. Biol. Chem. 268, 252-261). We present here the cDNA and amino acid sequences, and localization of the TGase in various tissues of limulus. The cloned cDNA for TGase consists of 2,884 base pairs. An open reading frame of 2,292 base pairs encodes a sequence comprising 764 residues of the mature protein with molecular masses of 87,021 and 87,110 Da, due to two different clones. The discrepancies of nucleotides in these two clones result in 3 amino acid exchanges at positions Gly452(GGT)-Arg(CGT), Ser477(AGT)-Cys(TGT), and Ile486(ATC)-Ser(AGC), respectively. Northern blot analysis on a total RNA extracted from various tissues of limulus revealed that TGase is expressed with 3.0 kilobases of a single type of mRNA, mainly in hemocytes, hepatopancreas, and gastric tissues. Limulus TGase shows significant sequence similarity with the mammalian TGase family, as follows: guinea pig liver TGase (32.7%), human factor XIIIa subunit (34.7%), human keratinocyte TGase (37.6%), and human erythrocyte band 4.2 (23.0%). Limulus TGase has a unique NH2-terminal cationic extension of 60 residues with no homology to the NH2 termini of mammalian TGases. Based on the alignment of the amino acid sequence of limulus TGase with those of the known TGase family, a phylogenetic tree representing an evolutionary relationship among the family members was inferred by the neighbor joining method.

Amino Acid Sequence↗
PubMed1993

Clinical aspects of primary thyroid lymphoma: diagnosis and treatment based on our experience of 119 cases.

We describe the clinical aspects of primary thyroid lymphoma, particularly diagnostic procedures and successful therapy based on our observation of 119 patients with primary thyroid lymphoma. Thyroid lymphoma occurred exclusively in the thyroid gland of patients with Hashimoto's thyroiditis as a rapidly growing mass in the thyroid gland. Therefore, progressively enlarging goiter and compression symptoms were the most common clinical manifestations. A significant number of patients in our series had subclinical hypothyroidism (14%) or overt hypothyroidism (27%) because of the coexistence of Hashimoto's thyroiditis. Whenever thyroid lymphoma is suspected, we recommend an ultrasound scan of the thyroid gland and fine needle aspiration biopsy as initial diagnostic procedures. Thyroid ultrasound showed characteristic asymmetrical pseudocystic pattern in 43 of the 46 patients (93%), and thyroid cytologic examination showed abundant monomorphic infiltration of lymphoid cells. Among 83 patients who underwent fine needle aspiration biopsy, 65 patients (78.3%) were diagnosed correctly and 10 patients (12%) had borderline cytologic results. Thus, 90% of patients with thyroid lymphoma were diagnosed or the diagnosis suspected based on fine needle aspiration biopsy. To confirm the diagnosis of lymphoma histologically and to determine the degree of malignancy, open biopsy taking 2-3 g tissue should be done for all cases. Treatment of thyroid lymphoma does not require resection of all lymphoma tissue or total thyroidectomy. Our successful treatment is radiation therapy combined with six courses of CHOP chemotherapy (cyclophosphamide, adriamycin, vincristine, prednisolone). This mode of therapy improved the 8-year survival rate to nearly 100% regardless of the histological type of malignancy.

Adult↗
PubMed1993

Motifs of cadherin- and fibronectin type III-related sequences and evolution of the receptor-type-protein tyrosine kinases: sequence similarity between proto-oncogene ret and cadherin family.

Immunoglobulin (Ig)-, fibronectin type III (FN-III)-, and cadherin-related sequences are often found in multiple repeats in the extracellular regions of various cell adhesion molecules. The amino acid sequences of 82 different cadherin-like repeats from 13 known members of the cadherin superfamily were compared for six highly conserved regions, and a frequency matrix represented as amino acids versus position matrix was calculated based on the alignment. With the frequency matrix, further members of the cadherin superfamily were searched for in the protein data base. It was found that the ret protein, a receptor-type-protein tyrosine kinase, contains cadherin-like repeats in the extracellular region. A similar analysis was also carried out for the FN-III superfamily. Nine receptor-type-protein tyrosine kinases were shown to exhibit significant similarities, in terms of sequence, with known FN-III-like repeats. Several receptor-type-protein tyrosine kinases have already been reported to have Ig-like repeats in their extracellular regions. Thus these receptor-type-protein tyrosine kinases--together with the remaining receptors, whose structures are not yet characterized--may be classified into at least four distinct groups based on the structural differences in the extracellular domains. A molecular phylogenetic tree inferred from the shared kinase domains of these receptor-type-protein tyrosine kinases revealed a close relationship between the branching patterns and the grouping based on the structural differences of the extracellular region.

Amino Acid Sequence↗
PubMed1993

Gene transfer of a part of a beta-lactamase gene?

beta-Lactamase is an enzyme which catalyzes the hydrolysis of the beta-lactam ring of penicillins and cephalosporins. By similarity analysis of amino acid sequences in a database, the amino acid sequence deduced from the nucleotide sequence of the upstream region of cytochrome c oxidase subunit II from Paracoccus denitrificans was found to have an unusually high score of homology to that of a portion of beta-lactamases from Gram-negative bacteria. Furthermore, the nucleotide sequences corresponding only to this region had a very high score of similarity among them. The phylogenetic tree constructed on the basis of the amino acid sequences was in accord with that constituted on the 5S rRNA's. Moreover, the molar G + C contents and the codon usage were similar to those in their respective bacteria. It is suggested, therefore, that the nucleotide sequence in P. denitrificans was positioned by a transfer of a part of a beta-lactamase gene formed as a result of gene duplication or it was formed by a deletion of the essential region of the beta-lactamase gene, although no beta-lactamase gene has been yet detected in P. denitrificans.

Amino Acid Sequence↗
PubMed1993

Intrathyroidal lymphocyte subsets, including unusual CD4+ CD8+ cells and CD3loTCR alpha beta lo/-CD4-CD8- cells, in autoimmune thyroid disease.

Intrathyroidal lymphocyte subsets were analysed in 13 euthyroid patients with autoimmune thyroid disease by two-colour flow cytometry and compared with subsets in peripheral blood. In both Graves' and Hashimoto's diseases, proportions of intrathyroidal CD5- B cells were higher than in peripheral blood. The numbers of such cells were correlated with serum levels of anti-thyroid microsomal antibodies. Proportions of T cells bearing alpha beta chains of T cell receptors (TCR alpha beta+ T; T alpha beta) and CD16+CD57+ natural killer (NK) cells were lower in the thyroid, but proportions of CD3hiTCR alpha beta-TCR gamma delta+ (T gamma delta) cells were not different. Proportions of CD4+Leu-8- helper T cells and CD4+CD57+ germinal centre T cells were higher and proportions of CD4+Leu-8+ suppressor-inducer T cells and CD8+CD57+ or CD8+CD11b+ suppressor T cells were lower than in the blood in both diseases. Proportions of CD5+ B cells were high in Graves' disease, and proportions of CD8+CD11b- cytotoxic T cells were high in Hashimoto's disease. Unexpectedly, CD4+CD8+ cells and CD3loTCR alpha beta lo/-CD4-CD8- cells were present in thyroid tissues of both diseases. These findings suggest that: (i) an imbalance in the numbers of regulatory T cells and of NK cells that had appeared in the thyroid resulted in the proliferation of CD5- B cells, which were related to thyroid autoantibody production; (ii) CD5+ B cells and cytotoxic T cells are important for the different pathological features in Graves' and Hashimoto's diseases, respectively; and (iii) intrathyroidal CD4+CD8+ cells and CD3loTCR alpha beta lo/-CD4-CD8- cells may be related to the pathogenesis of autoimmune thyroid disease.

Adolescent↗
PubMed1993

A long-term follow-up study of patients with non-toxic diffuse goitre in Japan.

OBJECTIVE: Although non-toxic diffuse goitre is a common disorder, little is known of the clinical course of patients. We therefore decided to investigate the long-term clinical outcome of patients with non-toxic diffuse goitre. DESIGN: A retrospective study. PATIENTS: Of 850 patients with non-toxic diffuse goitre who met our criteria and were seen in our thyroid clinic between 1977 and 1985, 108 who had been followed for from 5 to 14 years (mean 8 years) were entered in this study. All patients fulfilled our criteria having soft diffuse goitres, normal serum TSH and T4 concentrations, and undetectable antithyroglobulin and antithyroid microsomal antibodies. MEASUREMENTS: A family history of thyroid disease was obtained and the occurrence of Graves' ophthalmopathy was noted. Serum TSH and T4 concentrations, and antithyroglobulin and antithyroid microsomal antibodies were measured during the follow-up period. Thyroidal radioactive iodine uptake (RAIU), serum free T4 and free T3 concentrations, and TSH binding inhibitory immunoglobulin (TBII) activities were determined in all patients who were subsequently found to have abnormal serum TSH or T4 concentrations or signs of Graves' ophthalmopathy. RESULTS: Thirty-six of the 108 patients (33%) had a family history of autoimmune thyroid disease. Elevated serum T4 or free T4 concentrations and depressed serum TSH concentrations were found in six patients during the follow-up period. Hyperthyroid Graves' disease was diagnosed in four of the six patients, subacute thyroiditis in one, and transient post-partum thyrotoxicosis in one. Hypothyroidism was found in one patient who was diagnosed as having transient post-partum hypothyroidism. Euthyroid Graves' disease was diagnosed in one patient. Furthermore, six of these eight patients had a family history of autoimmune thyroid disease in first-degree relatives. CONCLUSION: During a prolonged follow-up period of patients with non-toxic diffuse goitre, Graves' disease was found in five of 108 patients (four hyperthyroid Graves' and one euthyroid Graves'), post-partum thyroid dysfunction in two, and subacute thyroiditis in one. Six of these eight patients had a family history of autoimmune thyroid disease in first-degree relatives. Long-term follow-up is necessary for patients with non-toxic diffuse goitre, especially those who have a family history of autoimmune thyroid disease.

Adolescent↗
PubMed1993

Thyroid histology of hyperthyroid Graves' disease with undetectable thyrotropin receptor antibodies.

To determine the histological characteristics of hyperthyroid Graves' disease with undetectable TSH receptor antibodies (TRAb), we examined the thyroid histological findings of patients with hyperthyroidism who were referred for subtotal thyroidectomy and who lacked circulatory TRAb. Four patients had undetectable TRAb (6.4 +/- 4.2%) before treatment (group A). Their pathological and clinical findings were compared with those of four patients who had hyperthyroid Graves' disease with detectable TRAb (83.8 +/- 8.3%) before treatment (group B). The groups were matched for sex, age, duration of antithyroidal drug therapy, anti-Tg antibody, and antimicrosomal antibody levels. All patients were in a euthyroid state just before operation. Papillate hyperplastic epithelia in group A were significantly less severe than in group B. Enlarged colloids were not observed in two of the four patients in group A but were observed in all four patients in group B. Moderate or marked lymphocytic infiltrations were observed in all patients in group A but were virtually absent in group B. Based on these results, it is probable that hyperthyroid Graves' disease with undetectable TRAb titers represents an early stage or subtype of usual hyperthyroid Graves' disease in which there is marked or moderate lymphocytic infiltration.

Adolescent↗