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S Nakai

Publications and source records attributed to S Nakai.

At least 217 records · Page 12Linked to original sources
PubMed1988

Dispersed localization of D segments in the human immunoglobulin heavy-chain locus.

We have studied the organization of the human immunoglobulin heavy-chain genes by pulse field gel electrophoresis as well as by isolation of cosmid clones. The total length of the heavy-chain variable region locus was estimated to be approximately 3000 kb. We found that D segments including a recently isolated D5 segment were dispersed among VH segments. We identified a pseudo V segment 18 kb 3' to the D5 segment in isolated cosmid clones. A 300 kb fragment produced by MluI digestion contained VH, D, JH segments and the distance between VH and D was estimated to be approximately 240 kb. Overlapping cosmid clones containing the human D1, D2, D3, D4, JH, Cmu and C delta genes were isolated. Restriction maps of these regions indicated that the distance between D and JH is about 22 kb. A partial restriction map of the VH locus was constructed using the pulse field gel electrophoresis technique and deletion of VH segments in B cells.

Amino Acid Sequence↗
PubMed1988

Human immunoglobulin D segments: isolation of a new D segment and polymorphic deletion of the D1 segment.

We have isolated and identified a new human germline D segment which is not physically linked to the known D cluster. The nucleotide sequence of the new D segment was highly homologous with the known D segments. Frequent polymorphic deletion of the D1 segment was found in the Japanese population. Nucleotide sequences surrounding the deletion indicate that homologous recombination is likely to be responsible for the deletion of the D1 segment.

Amino Acid Sequence↗
PubMed1988

Site-specific mutagenesis of the human interleukin-1 beta gene: the role of arginine residue at the N-terminal region.

Using the expression system for site-specific mutagenesis in Escherichia coli, we have made deletion mutants at the N-terminal or C-terminal region of human interleukin-1 beta (IL-1 beta) consisting of 153 amino acids. The truncated mutants showed that at least 147 amino acids (numbers 4-150) in IL-1 beta are necessary for the exertion of biological activity. When we changed the arginine at the 4th position (Arg4) in IL-1 beta to other specific amino acids, there was a marked difference in the relative extent of biological and receptor binding activities among the mutants. The order of the mutants was Arg4 = Lys4 greater than Gln4 greater than Gly4 = des-Arg4 greater than Asp4. Our results demonstrate that the arginine residue at the 4th position in IL-1 beta is important, but not essential, for IL-1 beta to exhibit its biological and receptor binding activities, and the positive charge at this site plays a key role for IL-1 beta to exert the activities.

Arginine↗
PubMed1988

Secondary structure prediction and determination of proteins--a review.

The rapid increase in sequence data in combination with a greater understanding of the forces regulating protein structure has been the impetus for an upsurge in the development of theoretical prediction methods. These methods have afforded protein chemists the ability to identify and quantify the various secondary structures along the protein chain. Concurrently, various physico-chemical techniques have been developed such as nuclear Overhauser enhancement n.m.r. and laser Raman spectroscopy. In addition, traditional methods such as infrared and circular dichroism spectroscopy have been refined. Although both predictive and physico-chemical techniques are limited in the types of secondary structure they are capable of determining, they have provided valuable information with regards to protein folding and topology in the absence of X-ray data, and have formed the basis for the development of improved methods for secondary structure determination. This paper reviews some of the predictive and physico-chemical methods presently used to determine protein secondary structure.

Chemical Phenomena↗
PubMed1988

Separation of immunoglobulins and lactoferrin from cheese whey by chelating chromatography.

Different adsorption and chelating chromatographic methods were used to isolate immunoglobulins and lactoferrin from cheese whey. Among three adsorption solid supports (silica, controlled pore glass, and alumina), controlled pore glass showed the highest adsorption of immunoglobulins; however, its capacity was low. 1,4-Butanediol diglycidyl etheriminodiacetic acid on Sepharose 6B was loaded with copper ion and used for the same purpose. Of the two peaks eluted using pH gradient, the first yellowish peak was rich in lactoferrin and the second was rich in Ig. The purity of IgG in the Ig rich fraction as indicated by radial immunodiffusion was 77.2 and 53.0% for acid whey and Cheddar cheese whey, respectively. The capacity of the column was high; a 25-ml copper charged column could absorb Ig from 1 L of cheese whey. Modification of histidine residues in Ig with diethyl pyrocarbonate almost completely eradicated the adsorption, implicating the coordination compound formation between histidine in Ig and Cu on the chelating column as the adsorption mechanism. Enzyme-linked immunosorbent assays of the Ig thus separated demonstrated their binding activity against lipopolysaccharides extracted from Escherichia coli, Salmonella typhimurium, and Bordetella parapertussis.

Cheese↗
PubMed1988

Separation of immunoglobulin and transferrin from blood serum and plasma by metal chelate interaction chromatography.

Metal chelate interaction chromatography was used to separate Ig, transferrin, and albumin from blood serum and blood plasma. A column was packed with iminodiacetic acid: 1,4-butanediol diglycidyl Sepharose 6B or Sephacryl S-300 and loaded with copper, zinc, nickel, or cobalt ion. Radial immunodiffusion assay indicated that Ig-rich fractions of blood serum obtained from Zn-, Ni-, Co-, and Cu-loaded columns contained 23.2, 81.3, 79.4, and 98.1% active IgG, respectively. Transferrin was recovered from the second peak. When the same conditions of metal chelate interaction chromatography were used for blood plasma, hemoglobin tended to bind strongly to the Cu-loaded column and was eluted only with 50% ethanol. Modification of histidine residues in Ig and transferrin with diethyl pyrocarbonate almost completely destroyed their binding ability to the column. Immunoglobulin G separated showed antilipopolysaccharide antibody activity against Escherichia coli, Salmonella typhimurium, and Bordettella parapertussis.

Animals↗
PubMed1988

[Interleukin 1 and gliomas: immunohistochemical and immunocytochemical examinations].

Interleukin 1 is a monokine produced by macrophage and has an ability to activate thymocytes. In addition to the immunological regulatory effect, interleukin 1 has attracted a great deal of investigators as a new peptide hormone that was secreted by many cells and has a various physiological activities. In central nervous systems, interleukin 1 promotes the glial cells proliferations on the injured brain and the fetal brain. The cell sources of interleukin 1 in central nervous systems are considered to the microglial cells. On gliomas, Lachmann and Dinarello reported growth promoting effect of IL-1 on U-373 MG human glioblastoma cell. The authors investigated the roles and effects of IL-1 on the growth of gliomas using recombinant human IL-1 beta and anti-HuIL-1 beta monoclonal antibody. On Immunohistochemistry, paraffin sections of 10 cases of gliomas were stained with immunoperoxidase method using anti-human IL-1 beta and anti-GFAP mouse monoclonal antibody. All astrocytomas examined and 2 of 4 glioblastomas were stained by anti-IL-1 beta. The origin of IL-1 that was stained by immunoperoxidase staining is unknown. The authors think it that IL-1 existed in glioma cells were secreted by microglial cells or that the glioma cells themselves secreted IL-1. In either case, IL-1 must be related to the growth of glioma in situ. On immunocytochemistry, U-373 MG human glioblastoma cells purchased from ATCC were incubated on cover-slip with 0 and 10 U/ml of rHuIL-1 beta for 3 or 7 days. The cells were stained with immunoperoxidase method using anti-GFAP monoclonal antibody.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Thoracic disc herniation. Surgical treatment in 23 patients.

The authors' surgical procedure for the treatment of symptomatic thoracic disc herniation has consisted of total discectomy of the involved intervertebral disc, followed by intervertebral body fusion using autogenous iliac bone through an anterior approach. The authors prefer the extrapleural approach to the thoracic vertebrae because of simplified postoperative care with minimum surgical interference with respiratory function. During the past 16 years, 23 patients with symptomatic thoracic disc herniation have been treated by this procedure. Preoperatively all 23 patients presented with some measure of paraplegia, with difficulty in walking. Their clinical presentation was analyzed and diagnostic aids to the thoracic disc herniation by radiographic examinations were assessed. The radiographic abnormality of ossification of the yellow ligament (OYL) coinciding with the involved thoracic disc level was noted. The results in all 23 patients with this procedure were favorable. Based on the results of this series, this procedure is recommended for the treatment of symptomatic thoracic disc herniation.

Adult↗
PubMed1988

[A case of right adrenal myelolipoma diagnosed preoperatively and review of literature in Japan].

Fifty-nine years old female who complained of right back pain was diagnosed as having right adrenal myelolipoma preoperatively by ultrasound, CT and other examinations. The patient was cured by surgery. The resected tumor was 11.5 X 10.5 X 8.5 cm in size and 470 g in weight. Histopathological diagnosis was myelolipoma of Soós's type 1. Sixteen cases of myelolipoma, including our case have been reported in Japanese literature. The age of patients ranged from 20 to 60 (average 49.1) and male-female ratio was 11:5. Most patients presented with abdominal pain and abdominal mass, and had complication of obesity and hypertension. The lesion was more common on the right side (11:5). Their size was 3-21 cm (average 10.9 cm) and their weight was 10-1, 930 g (average 823 g). Adrenal myelolipoma can be certainly diagnosed preoperatively by ultrasound, CT and other examinations. Adrenal tumors showing normal adrenal endocrine function and fat density on CT examination indicate that they could be myelolipoma in their nature.

Adrenal Gland Neoplasms↗
PubMed1987

Purification and characterization of recombinant human interleukin-1 beta produced in Escherichia coli.

Recombinant human interleukin-1 beta (rIL-1 beta) produced in Escherichia coli was purified to homogeneity by a combination of mass ion exchange column chromatography, ion exchange and gel filtration high performance liquid chromatography. The purified rIL-1 beta had a molecular weight of 18 kD on SDS-polyacrylamide gel electrophoresis and an isoelectric point of 6.9 on analytical isoelectric focusing. These values were almost same as those of natural interleukin-1 beta. The amino acid composition and amino acid sequence of the amino terminal region were consistent with those deduced from the cDNA sequence. In addition, the primary structure was confirmed by peptide mapping with lysyl-endopeptidase on reverse phase HPLC. Besides rIL-1 beta with amino terminal Ala, two molecular species, [Met0] rIL-1 beta and [desAla1] rIL-1 beta, were also obtained. Biological and physicochemical properties of the three species of rIL-1 beta were compared.

Amino Acid Sequence↗
PubMed1987

cDNA cloning of IL-1 alpha and IL-1 beta from mRNA of U937 cell line.

Clones of cDNAs encoding growth inhibitory factors for human melanoma cell line A375 were isolated from cDNA library prepared by using mRNA derived from human histiocytic lymphoma cell line U937 induced with PMA and further stimulated with LPS. Cloning was achieved using Okayama-Berg cDNA expression vector system that permits expression of the inserted cDNA segments in mammalian cells. By assaying the transfected COS-1 cells supernatants and cell extracts, we isolated two distinct cDNA clones encoding growth inhibitory factors. It was determined by the nucleotide sequences of the inserts, the cDNAs corresponded to IL-1 alpha and -1 beta. Our results indicate U937 cells can be induced to produce both interleukin-1s.

Amino Acid Sequence↗
PubMed1987

Structure and expression of human B cell stimulatory factor-2 (BSF-2/IL-6) gene.

The chromosomal DNA segment of human B cell stimulatory factor-2 (BSF-2/IL-6) was isolated and characterized by nucleotide sequence analysis. The human BSF-2/IL-6 gene consists of five exons and four introns and its organization shows a distinctive similarity to granulocyte colony-stimulating factor gene. The two genes have the same number of exons and introns and the size of each exon is strikingly similar. The BSF-2/IL-6 mRNA was found to be constitutively expressed in a human T cell leukemia virus-1 transformed T cell line, TCL-Na1, a bladder cell carcinoma line, T24, and an amnion derived cell line, FL. The BSF-2/IL-6 mRNA was also found to be inducible with interleukin-1 beta in an astrocytoma line, U373 and a glioblastoma line, SK-MG-4. S1 mapping and primer extension analyses showed the presence of multiple initiation sites and the preferential utilization of a different initiation site for each individual tissue tested.

Amino Acid Sequence↗
PubMed1987

Isolation of bovine immunoglobulins and lactoferrin from whey proteins by gel filtration techniques.

Whey is a suitable source of immunoglobulins and lactoferrin to enrich infant formulas. Gel filtration on Sephacryl S-300 and on Fractogel TSK HW-55 was used to isolate immunoglobulins from colostral whey, acid whey, and Cheddar cheese whey. The SDS-PAGE and immunoelectrophoresis techniques indicated that the purity of the fractions from fractionation on Sephacryl S-300 was better than that by fractionation on TSK HW-55 column. Biological activity of fractions from the Sephacryl S-300 column as assessed by immunochemical analysis was 99, 83.3, and 92% for colostral, acid, and sweet wheys. The well-proven antimicrobial agent, lactoferrin, was isolated from sweet whey by heparin-attached Sepharose. Lactoferrin selectively adsorbed to the column was subsequently eluted with 5 mM Veronal-HCl containing .5 M NaCl, pH 7.4. Purity of the isolated protein was confirmed by SDS-PAGE and immunoelectrophoresis.

Animals↗
PubMed1986

High- and low-affinity interleukin 2 receptors: distinctive effects of monoclonal antibodies.

We previously established several mouse hybridoma cell lines producing monoclonal antibodies against the human interleukin 2 (IL 2) receptor molecule. As they bind to both high- and low-affinity IL 2 receptors, their effects on binding of 125I-labeled IL 2 to high- and low-affinity receptors were examined by Scatchard plot analysis. Two of these monoclonal antibodies, HIEI and H-47, reduced the IL 2 binding affinity of high-affinity receptors from a Kd of 14 to 20 pM to a Kd of 110 to 140 pM, but slightly raised that of low-affinity receptors. These two antibodies scarcely affected the numbers of high- and low-affinity receptors. On the other hand, H-31 completely blocked IL 2 binding to both high- and low-affinity receptors, and H-A26 slightly reduced the affinities of both high- and low-affinity receptors, from 17 pM to 28 pM and from 28 nM to 54 nM, respectively. H-48 had little affect on IL 2 binding to high- or low-affinity receptors. By use of these monoclonal antibodies, the inhibitory effect of IL 2 on growth of an HTLV-I-immortalized T cell line was demonstrated to be transmitted from high-affinity, but not low-affinity, receptors.

Animals↗