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K Hayashi

Publications and source records attributed to K Hayashi.

At least 19 recordsLinked to original sources
PubMed1992

Purification and amino-acid sequence of a nerve growth factor from the venom of Vipera russelli russelli.

Nerve growth factor (NGF) was purified from the venom of Vipera russelli russelli by Sephadex G-50 gel filtration, S-Sepharose column chromatography and Blue-Sepharose CL-6B column chromatography. The purified NGF was found to be a glycoprotein, whose apparent molecular mass was estimated to be about 17.5 kDa by SDS-PAGE. The amino-acid sequence was determined by a combination of conventional methods. The V. r. russelli NGF was composed of 117 amino-acid residues with one residue, Asn-21, being N-linked glycosylated and the molecular mass of its protein portion was calculated to be 13,280 Da.

Amino Acid Sequence↗
PubMed1992

Genomic structure of the human caldesmon gene.

The high molecular weight caldesmon (h-CaD) is predominantly expressed in smooth muscles, whereas the low molecular weight caldesmon (l-CaD) is widely distributed in nonmuscle tissues and cells. The changes in CaD isoform expression are closely correlated with the phenotypic modulation of smooth muscle cells. During a search for isoform diversity of human CaDs, l-CaD cDNAs were cloned from HeLa S3 cells. HeLa l-CaD I is composed of 558 amino acids, whereas 26 amino acids (residues 202-227 for HeLa l-CaD I) are deleted in HeLa l-CaD II. The short amino-terminal sequence of HeLa l-CaDs is different from that of fibroblast (WI-38) l-CaD II and human aorta h-CaD. We have also identified WI-38 l-CaD I, which contains a 26-amino acid insertion relative to WI-38 l-CaD II. To reveal the molecular events of the expressional regulation of the CaD isoforms, the genomic structure of the human CaD gene was determined. The human CaD gene is composed of 14 exons and was mapped to a single locus, 7q33-q34. The 26-amino acid insertion is encoded in exon 4 and is specifically spliced in the mRNAs for both h-CaD and l-CaDs I. Exon 3 is the exon that encodes the central repeating domain specific to h-CaD (residues 208-436) together with the common domain in all CaD (residues 73-207 for h-CaD and WI-38 l-CaDs, and residues 68-201 for HeLa l-CaDs). The regulation of h- and l-CaD expression is thought to depend on selection of the two 5' splice sites within exon 3. Thus, the change in expression between l-CaD and h-CaD might be caused by this splicing pathway.

Alternative Splicing↗
PubMed1992

Primary non-Hodgkin malignant lymphoma of the breast. An immunohistochemical study of seven patients and literature review of 152 patients with breast lymphoma in Japan.

BACKGROUND: The breast is rarely a primary site for extranodal malignant lymphoma. Most reported primary non-Hodgkin malignant lymphomas of the breast (PBL) are of B-cell phenotype. METHODS: Histologic and immunohistochemical analyses of seven patients with PBL and a statistical analysis of 152 patients with PBL reported in the Japanese literature were performed. RESULTS: Malignant lymphoma could not be predicted preoperatively with clinical and radiologic findings; breast carcinoma, fibroadenoma, and phyllodes tumor were the preoperative diagnoses. All patients were women; they ranged in age from 31 to 80 years (mean, 57.6 years). The right breast was involved initially in five patients. In four, only the breast was involved (Stage I), whereas in three, the ipsilateral axillary lymph nodes (Stage II) were involved at diagnosis. According to the Working Formulation, all patients belonged to the intermediate grade and were classified as having diffuse large cell (five patients) or mixed (two patients) lymphoma. Immunophenotypic analysis revealed that all patients had B-cell lymphoma. No patients had lymphoepithelial lesions, which is the characteristic feature in categorizing a lymphoma as a mucosa-associated lymphoid tissue (MALT) lymphoma. A statistical analysis of the patient reported in the Japanese literature has divided PBL into two types: a bilateral type that affects younger women and a unilateral type that has a broad age distribution, but preponderantly occurs in older women. The age and stage at diagnosis were significant prognostic factors in predicting the survival time, but the location and size of the tumor at initial presentation, histopathologic type, terminal leukemic manifestation, and treatment modality were not. CONCLUSIONS: This study indicates that most PBL are diffuse large cell lymphoma of B-cell phenotype and that the age and stage at diagnosis are significant prognostic factors.

Adult↗
PubMed1992

A nuclear gene encoding beta-amylase of sweet potato.

A nuclear AmyB gene from sweet potato encoding beta-amylase (beta Amy) that is abundant in tuberous roots and inducible in other organs by an exogenous supply of sucrose or polygalacturonic acid, was isolated and characterized. Genomic Southern blot hybridization, restriction maps of independently isolated phage lambda genomic clones, and the nucleotide sequence of AmyB compared with that of the cDNA, all suggested that beta Amy of sweet potato is encoded by a gene that is present in a single copy per haploid genome. In the sequence of AmyB, the sequence that is identical to that of the cDNA was split into seven exons by six introns, and the transcription of this gene starts from multiple sites 26 to 30 bp downstream from a potential TATA-box sequence, 5'-TATATAA. In the 5'-upstream region of AmyB, there are sequences homologous to those conserved in the 5'-upstream regions of genes encoding sporamin, which are regulated similarly to AmyB. The 5'-upstream region of AmyB also contains sequences to which several previously known plant nuclear factors bind.

Amino Acid Sequence↗
PubMed1992

Detection of bcl-2 protein and bcl-2 messenger RNA in normal and neoplastic lymphoid tissues by immunohistochemistry and in situ hybridization.

bcl-2 protein has been detected in surgical specimens and cultured permanent cell lines of non-Hodgkin's lymphomas and leukemias using enzyme immunohistochemistry and immunofluorescence with anti-bcl-2 monoclonal antibodies. Of 40 surgical specimens, bcl-2 protein was expressed in 50% of B-cell and 41% of T-cell lymphomas, both with and without the bcl-2 gene rearrangement. In investigations of 38 hematopoietic cell lines, bcl-2 protein was detected not only in lymphoid cell lines but also in myeloid cell lines. In situ hybridization and immunohistochemical analysis of reactive lymph nodes showed that lymphocytes in mantle zones and paracortical areas expressed bcl-2 protein consistent with the messenger RNA distribution and that germinal center cells showed abundant bcl-2 transcript, despite the absence of detectable bcl-2 protein. These results suggest that bcl-2 protein is broadly expressed in various hematopoietic neoplasms not restricted in t(14; 18) lymphomas and that germinal center cells may be involved in some arrest of bcl-2 protein expression at the posttranscriptional level.

Blotting, Northern↗
PubMed1992

Denervation of dopaminergic neurons with 6-hydroxydopamine increases nerve growth factor content in rat brain.

Denervation of dopaminergic neurons by intra nigral injection of 6-hydroxydopamine (6-OHDA) increased nerve growth factor (NGF) content in the cortex and hippocampus, both of which are innervated by cholinergic neurons. The increase continued during an observation period of 0.5-28 days after the lesion. The time course of changes in NGF content was quite different from that of cholinergic neuron denervation. The decreased dopamine content produced in the striatum by 6-OHDA injection was not recovered during the observation period. These results suggest that dopaminergic neuron damage may affect NGF synthesis.

Animals↗
PubMed1992

Aberrations of the p53 tumor suppressor gene in human non-small cell carcinomas of the lung.

Aberrations of the p53 gene in 115 surgical specimens of non-small cell carcinomas of the lung were examined by single-strand conformation polymorphism analysis of polymerase chain reaction products. Structural abnormalities of the p53 gene were observed in 60 tumors (52%), i.e., 8 of 14 large cell carcinomas, 24 of 58 adenocarcinomas, 25 of 37 squamous cell carcinomas, and 3 of 6 adenosquamous carcinomas. Direct sequencing of abnormal DNA fragments revealed 45 single-base substitutions, 9 deletions or insertion of a short nucleotide sequence, and 3 two-base substitutions in 57 tumors. In the other 3 tumors, loss of one of the p53 alleles was observed, with no mutation in the other allele. Allelic loss of the p53 gene was observed in 14 of 43 informative cases (33%), and in 11 of the 14 cases the remaining allele was mutated. The aberrations of the p53 gene were not limited to a particular histological type or clinical stage. Their high frequency suggests that they were involved in the genesis of non-small cell carcinomas of the lung. The mutation frequency (46%) of the p53 gene in tumors carrying mutated ras genes was essentially the same as the overall frequency in lung cancers, suggesting that accumulation of mutations in these two genes in a tumor is a random phenomenon.

Base Sequence↗
PubMed1992

The heparin binding site of human extracellular-superoxide dismutase.

Extracellular-superoxide dismutase (EC-SOD) is a secretory glycoprotein that is major SOD isozyme in extracellular fluids. We revealed the possible structure of the carbohydrate chain of serum EC-SOD with the serial lectin affinity technique. The structure is a biantennary complex type with an internal fucose residue attached to asparagine-linked N-acetyl-D-glucosamine and with terminal sialic acid linked to N-acetyllactosamine. EC-SOD in plasma is heterogeneous with regard to heparin affinity and can be divided into three fractions: A, without affinity; B, with intermediate affinity; and C, with high affinity. It appeared that this heterogeneity is not dependent on the carbohydrate structure upon comparison of EC-SOD A, B, and C. No effect of the glycopeptidase F treatment of EC-SOD C on its heparin affinity supported the results. A previous report showed that both lysine and arginine residues probably at the C-terminal end, contribute to heparin binding. Recombinant EC-SOD C treated with trypsin or endoproteinase Lys C, which lost three lysine residues (Lys-211, Lys-212, and Lys-220) or one lysine residue (Lys-220) at the C-terminal end, had no or weak affinity for the heparin HPLC column, respectively. The proteinase-treated r-EC-SOD C also lost triple arginine residues which are adjacent to double lysine residues. These results suggest that the heparin-binding site may occur on a "cluster" of basic amino acids at the C-terminal end of EC-SOD C. EC-SOD is speculated to be primarily synthesized as type C, and types A and B are probably the result of secondary modifications. It appeared that the proteolytic cleavage of the exteriorized lysine- and arginine-rich C-terminal end in vivo is a more important contributory factor to the formation of EC-SOD B and/or EC-SOD A.

Amino Acid Sequence↗
PubMed1992

Detailed structural analysis of asparagine-linked oligosaccharides of the nicotinic acetylcholine receptor from Torpedo californica.

The structures of the major oligosaccharide moieties of the nicotinic acetylcholine receptor (AcChoR) protein from Torpedo californica have been reported [Nomoto, H., Takahashi, N., Nagaki, Y., Endo, S., Arata, Y. and Hayashi, K. (1986) Eur. J. Biochem. 157, 233-242] to be high-mannose types. Here we report detailed analyses of the structures of the remaining oligosaccharides in this receptor. The sialylated oligosaccharides released by glycopeptidase (almond) digestion were separated according to the number of sialic acid residues using high-performance anion-exchange chromatography with pulsed amperometric detection. After removal of sialic acid from each fraction, the resulting neutral oligosaccharides were separately pyridylaminated and were analyzed by a combination of sequential exoglycosidase digestion and HPLC, then identified on a two-dimensional sugar map. The structures of two desialylated pyridylamino-oligosaccharides were further analyzed by high-resolution proton NMR. Each oligosaccharide was composed of species containing varying numbers of sialic acids. The desialylated complex-type oligosaccharides of AcChoR consisted of ten, eight and one different biantennary, triantennary and tetraantennary oligosaccharide, respectively. The biantennary oligosaccharides were divided into two groups; oligosaccharides with fucose at the proximal N-acetylglucosamine (six varieties) and oligosaccharides without fucose (four varieties). Each group consisted of species differing in the number of terminal galactose residues. The major component of the biantennary oligosaccharides had two galactose residues at the non-reducing termini. The terminal alpha-galactose residue(s) linked to C3 of beta-galactose were found in the fucose-containing biantennary oligosaccharides (two varieties). The triantennary oligosaccharides were also divided into two groups; oligosaccharides with (four varieties) and without (four varieties) besecting N-acetylglucosamine. These groups were composed of species differing in the number of terminal galactose residues. The major component of the triantennary oligosaccharides was fully galactosylated with three galactose residues. An unusual group, Gal beta 1-3GlcNAc, was present in low levels in the triantennary oligosaccharides. In contrast, the tetraantennary oligosaccharide was composed of only one species, which is fully galactosylated with four galactose residues.

Animals↗
PubMed1992

Molecular genetic and immunological analysis of dystrophin of a young patient with X-linked muscular dystrophy.

We examined the nucleotide sequence of deleted part of dystrophin mRNA and its translational product with immunoblot and immunohistochemical methods in a 6-year-old boy with a deleted DMD/BMD gene. On Southern blot analysis of his genomic DNA, we found a deletion of exons 10 to 37 in the DMD/BMD gene, which was expected to preserve the translational open reading frame (ORF). Dystrophin mRNA from his biopsy sample was amplified by polymerase chain reaction (PCR) and sequenced. The mRNA lacked the sequence corresponding to the gene from exons 10-37, and the translational ORF was preserved. The transcript was expected to code a 260 kDa protein. Dystrophin expressed in this patient was investigated with immunological methods. A 260 kDa protein was detected by immunoblot analysis with antidystrophin antiserum against nondeleted regions. These observations confirmed the preservation of the reading frame and the 260 kDa protein was produced as a mutant dystrophin. All these are compatible with the diagnosis of BMD. However, the immunohistochemical pattern of his muscle cells was peculiar. With deleted-region-directed antiserum, the membrane was not stained at all as in DMD patients. In contrast, with nondeleted-region-directed antiserum, all the muscle cell membrane was stained continuously as in non-DMD/BMD individuals. These are quite different from the staining pattern in most BMD patients where muscles are stained patchily or discontinuously.

Amino Acid Sequence↗
PubMed1992

Mutations of p53 gene and their relation to disease progression in B-cell lymphoma.

The alteration of p53 tumor suppressor gene was studied in 48 patients with B-cell lymphoma. A sequential combined technique of polymerase chain reaction-mediated single-strand conformational polymorphism (PCR-SSCP) or reverse transcription (RT)-PCR-SSCP and direct sequencing were used as a simple and sensitive approach to analyze nucleotide changes. By these methods, we identified 8 missense point mutations and 2 codon deletions in 9 of the 48 patients. These mutations were located in or close to the evolutionally highly conserved regions of the p53 gene. Eight of nine patients having p53 gene alterations were in advanced clinical stage (IV). It is the first report of p53 gene mutations in follicular and diffuse lymphoma. These observations suggest that the p53 gene alteration may play an important role in lymphomagenesis and/or disease progression in some types of B-cell lymphoma.

Base Sequence↗
PubMed1992

Human fibroblast cells synthesize and secrete nerve growth factor in culture.

Using our enzyme immunoassay system developed for recombinant hNGF, we examined the synthesis and secretion of human NGF (hNGF) by human fibroblast (WS-1) cells. The amount of the factor secreted by WS-1 cells increased linearly and a significant amount of NGF was detected in the conditioned medium of WS-1 cultures. WS-1 NGF showed properties identical to those of recombinant human NGF in immunoreactivity and molecular weight. An increase in cell density or the withdrawal of serum from the culture medium caused a drastic decrease in the rate of NGF secretion. These results suggest that WS-1 cells are able to synthesize and secrete hNGF in culture and that the synthesis/secretion is regulated in a growth phase-dependent manner.

Cell Division↗
PubMed1992

Mutations in the P53 tumour suppressor gene in primary lung cancer in Japan.

The reverse transcription-polymerase chain reaction-single strand conformation polymorphism (RT-PCR-SSCP) analysis and sequencing were used to examine p53 gene alterations in 18 surgical specimens of primary lung cancers obtained in Japan. Somatic mutations resulting in amino acid changes were found in eight of the 18 cases (44%). Seven missense mutations were located in amino acid-conserved domains or their vicinities (codons 110 to 307). Most mutations were found at G-C pairs, suggesting that specific carcinogens are involved in the etiology of lung cancer. The p53 mutations showed a significant association with a history of smoking (P = 0.0294). We suggest that the p53 mutations may be associated with smoking-induced lung carcinogenesis.

Adenocarcinoma↗
PubMed1992

Expression, regulation, and tissue distribution of the Ch21 protein during chicken embryogenesis.

The Ch21 protein is one of the marker proteins whose synthesis and secretion by differentiating tibia chondrocytes is progressively increased during chicken embryogenesis (Descalzi-Cancedda, F., Manduca, P., Tacchetti, C., Fossa, P., Quarto, R. and Cancedda, R. (1988) J. Cell Biol. 107, 2455-2463). We report the corresponding full-length cDNA sequence and the complete primary structure of the protein, which contains a 20-residue signal peptide. The synthesis of the protein is directed by a 1450-base mRNA characterized by an unusually long 5'-untranslated leader sequence and is regulated only at the transcriptional level as shown by run-off transcription assays. During differentiation, maximal expression of the protein characterizes stage II hypertrophic chondrocytes. In situ hybridization on embryo sections reveals that the protein is expressed by several structures derived from the chondrogenic lineage and that, in addition, it is a major translational product in granulocytes. High cell density largely influences the expression of the Ch21 protein in chondrocyte cultures. When embryonic avian cells of different origin are grown to confluency, the expression of the Ch21 protein is observed in only some of the cell lines. Thus quiescence per se is not the primary factor determining the expression of the protein.

Amino Acid Sequence↗
PubMed1992

Purification and structural analysis of hippocampal cholinergic neurostimulating peptide.

Hippocampal soluble fraction stimulates acetylcholine (AcCho) synthesis of medial septal nuclei in explant culture system. This stimulating activity was purified from 10-12-day-old rat hippocampus. During purification, the activity was separated into two fractions and a previously unreported peptide was purified from one fraction. The structure of this novel peptide is acetyl-Ala-Ala-Asp-Ile-Ser-Gln-Trp-Ala-Gly-Pro-Leu and we designated it as hippocampal cholinergic neurostimulating peptide (HCNP). Synthesized HCNP and de-acetylated HCNP (free-HCNP) stimulated AcCho synthesis of medial septal nuclei culture, in a dose-dependent manner, but not cultures of corpus striatum or anterior spinal cord. Mean half-maximal concentrations of HCNP and free-HCNP in AcCho synthesis of medial septal nuclei culture were 1.0 +/- 0.3 x 10(-10) M and 1.0 +/- 0.6 x 10(-11) M, respectively. Affinity purified polyclonal antibody to the free-HCNP neutralized the activity of crude hippocampal extract, as well as synthetic HCNP and free-HCNP. These observations suggested that HCNP was present in the hippocampal extract and was involved in development of specific cholinergic neuron in central nervous system.

Amino Acid Sequence↗
PubMed1992

[Reevaluation of US and CT findings in adult intussusception].

Computed tomographic (CT) and ultrasonographic (US) findings of 10 adult patients with 11 intussusceptions were retrospectively analyzed. Through close scrutiny of wall structures of intussusceptums and mesenteric fat, new features of adult intussusceptions were found: 1. The returning walls were thicker than the entering walls in 10 of 11 intussusceptums. 2. The neck of the returning wall was thicker than its head in eight of nine intussusceptums. 3. Longitudinal compression of the wall and venous congestion resulting from an inside out turning of the wall structure were thought to be the cause of thickening of the returning wall. 4. Invaginated mesenteric fat tended to be located at the head (apex) in two of seven intussusceptions, making differentiation from intussusception caused by lipoma difficult. 5. The leading masses were detectable as apical soft tissue density masses in eight of 10 intussusceptions. These findings contradict those of previous reports on adult intussusceptions.

Adult↗
PubMed1992

Injury-induced reduction of acidic fibroblast growth factor levels in the distal parts of rat sciatic nerve.

Acidic fibroblast growth factor (aFGF) level in sciatic nerve after lesioning was measured by enzyme immunoassay to determine if aFGF functions as a neurotrophic factor like nerve growth factor (NGF). Whereas the NGF level increased in distal segments, the aFGF level there decreased after transection or crushing and recovered to the original level by 10 weeks after crushing. The amount of aFGF mRNA in the sciatic nerve was extremely low to supply the high level of protein found in the sciatic nerve. Sympathetic ganglia, dorsal root ganglia, and spinal cord, which contain neuronal cell bodies extending their axons into the sciatic nerve, showed a greater or similar level of aFGF as sciatic nerve. These results imply that aFGF is synthesized in neuronal cell bodies and distributed anterogradely into their axons. Difference of injury-induced changes in levels between aFGF and NGF suggests distinct mechanisms of the effects elicited from these factors on regeneration of the sciatic nerve.

Animals↗