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Biomedical subjects

H Hirano

Publications and source records attributed to H Hirano.

At least 271 records · Page 15Linked to original sources

T-cell adhesion induced by proteoglycan-immobilized cytokine MIP-1 beta.

Lymphocyte migration from blood into tissue depends on integrin-mediated adhesion to endothelium. Adhesion requires not only integrin ligands on the endothelium, but also activation signals because T-cell integrins cannot bind well until they are activated. The physiological 'triggers' for T-cell adhesion are unknown, but cytokines may be good candidates as they are released during inflammation and trigger adhesion in neutrophils and monocytes. We have identified a cytokine, macrophage inflammatory protein-1 beta (MIP-1 beta), that induces both chemotaxis and adhesion of T cells; MIP-1 beta is most effective at augmenting adhesion of CD8+ T cells to the vascular cell adhesion molecule VCAM-1. We reasoned that, as cytokines in vivo will be rapidly washed away, MIP-1 beta might be bound to endothelial surfaces and so induce adhesion in its immobilized form. Here we show that: (1) MIP-1 beta is present on lymph node endothelium; (2) immobilized MIP-1 beta induces binding of T cells to VCAM-1 in vitro. MIP-1 beta was immobilized by binding to proteoglycan: a conjugate of heparin with bovine serum albumin and cellular proteoglycan CD44 were both effective. We propose that MIP-1 beta and other cytokines with glycosaminoglycan-binding sites will bind to and be presented by endothelial proteoglycans to trigger adhesion selectively not only of lymphocyte subsets, but also of other cell types.

Cell Adhesion↗

Microsequence analysis of the N-terminally blocked proteins immobilized on polyvinylidene difluoride membrane by western blotting.

A technique has been developed for efficient deblocking and subsequent microsequencing of N-terminally blocked proteins immobilized on a polyvinylidene difluoride (PVDF) membrane at the picomole levels. In this technique, proteins were first separated by polyacrylamide gel electrophoresis and then transferred onto a PVDF membrane by Western blotting. The electroblotted proteins with N-terminal acetylserine or acetylthreonine could be deblocked on-membrane by treatment with trifluoroacetic acid vapor and sequenced by a gas-phase protein sequencer. Similarly, N-formylated proteins could be deblocked on-membrane in HC1 solution and then directly sequenced from the N-terminal amino acid. Proteins with N-terminal pyroglutamic acid were enzymatically deblocked by in situ pyroglutamyl peptidase digestion, and N-acetylated proteins were also enzymatically deblocked with acylamino acid-releasing enzyme (AARE) after on-membrane digestion with trypsin to generate the N-terminal peptide fragment. This tryptic digestion was required since AARE can remove the acetylamino acid only from a short peptide. Based on these four deblocking methods, we present a strategy for sequential deblocking and subsequent N-terminal sequence analysis of N-blocked protein immobilized on PVDF membrane.

Acetylation↗

Secretion of endogenous 16-kDa beta-galactoside-binding lectin from vitamin A-pretreated chick embryonic cultured skin.

Localization of endogenous beta-galactoside-binding 16-kDa lectin and its gene expression pattern were investigated during differentiation of chick embryonic skin in vivo and in vitro and were compared with those of a 14-kDa lectin. By light microscopy, immunostaining of the 16-kDa lectin was weak in the undifferentiated epidermis, while it became intense in the keratinized epidermis, particularly in the intermediate cells. Essentially the same staining pattern was observed both in vivo and in vitro. The gene expression pattern was consistent with these immunohistochemical observations. These results were similar to those of the 14-kDa lectin [1]. On the other hand, in the vitamin A-pretreated cultured skin, mucous metaplasia of the epidermis was induced and marked changes in localization of these two isolectins were observed. The 16-kDa lectin expression was increased in the epidermis, especially in the superficial cells, and the gene expression was detected in all layers of the epidermis. However, 14-kDa lectin expression was markedly reduced in the metaplastic epidermis. In the keratinized epidermis, detailed localization of these lectins under the electron microscope was almost the same. Both of them were located primarily along the plasma membrane, in the intercellular space, and in the desmosomes. In the mucous metaplastic epidermis, however, the localization of the 16-kDa lectin was completely different from that of the 14-kDa lectin; e.g., the former was detected in the mucous granules and on the microvilli of the superficial cells, while the latter was scarcely observed in the epidermis. The present results revealed that (1) the 16-kDa lectin as well as 14-kDa lectin were expressed during the epidermal differentiation and (2) much of the 16-kDa lectin was produced and secreted from the vitamin A-pretreated cultured epidermis, while 14-kDa lectin disappeared. In the view of these facts, it is suggested that (1) both 14- and 16-kDa lectins may play an important role in differentiation of the skin and (2) the gene expression of 14- and 16-kDa lectins is regulated independently.

Animals↗

Identification and characterization of stylar glycoproteins associated with self-incompatibility genes of Japanese pear, Pyrus serotina Rehd.

Japanese pear (Pyrus serotina Rehd.) exhibits gametophytic self-incompatibility. Following our previous findings that basic ribonucleases in the styles of Japanese pear are associated with self-incompatibility genes (S-RNases), stylar proteins with high pI values were analyzed by two-dimensional gel electrophoresis further to characterize S-RNases. A group of basic proteins of about 30 kDa associated with self-incompatibility genes were identified. These proteins contained sugar chains which reacted with concanavalin A and wheat germ agglutinin, and thus were designated as S-glycoproteins of Japanese pear. The fact that the S-glycoprotein was expressed at a much lower level in a self-compatible mutant than in the original variety suggested a role of S-glycoproteins in mediating self-incompatibility of Japanese pear. Immunoblot analysis indicated that S-glycoproteins are identical to previously identified S-RNases. The S-glycoproteins were predominantly expressed in the style, in the ovary in trace amounts, and not in leaf, pollen or germinated pollen. The N-terminal amino acid sequences of the S-glycoproteins showed homology not only with each other but also with those of the S-allele-associated proteins from plants of the family Solanaceae at levels of about 30-50%.

Alleles↗

Identification of three Wx proteins in wheat (Triticum aestivum L.).

Nullisomic analysis of waxy (Wx) protein of hexaploid wheat (Triticum aestivum L.) cv. "Chinese Spring" using two-dimensional polyacrylamide gel electrophoresis revealed that three Wx loci, Wx-A1, Wx-B1, and Wx-D1, located on chromosome arms 7AS, 4AL, and 7DS, produce three distinct Wx subunit groups, subunit group-A (SGA), SGB, and SGD, respectively. SGA has a higher molecular weight and a more basic isoelectric point (pI) than the other two. SGB and SGD have the same molecular weight but a slightly different pI range. Owing to the detection of these three subunit groups, we were able to identify the expression of three waxy genes in wheat endosperm and to find two types of mutants among Japanese wheat cultivars, one lacking SGA and the others SGB. These results suggest the possibility of breeding a waxy wheat.

Electrophoresis, Polyacrylamide Gel↗

CD45 expression by murine B cells and T cells: alteration of CD45 isoforms in subpopulations of activated B cells.

The CD45 family of high molecular weight cell surface glycoproteins is abundantly expressed by virtually all hematopoietic cells. CD45 molecules exist as multiple isoforms whose extracellular portions vary in protein structure and carbohydrate content but whose intracellular portions are highly conserved and possess tyrosine phosphatase activity. In this review we summarize current studies describing CD45 isoform expression on peripheral and thymic lymphocytes. Further, we analyze changes in CD45 isoform expression by selective populations of activated B cells.

Animals↗

An attempt to substitute the cell binding domain of human fibronectin in lambda phage J protein: computer design and expression.

We superimposed hydropathic indexes of the human fibronectin cell binding domain (CBD) on the lambda phage J protein by computer, and substituted 22 amino acids from the fibronectin CBD for a part of the lambda phage J protein. The fibronectin cell binding domain -Arg-Gly-Asp-Ser- (-RGDS-) localizes at the junction of hydrophobicity and hydrophilicity. We selected a similar hydrophobic-to-hydrophilic junction in the J protein region for substitution. This junction corresponds to 150 bp of the PstI fragment of J protein cDNA. We synthesized 150 bp of the relevant PstI fragment that includes the cell binding domain region. The region was then constructed by serial cloning as an expression vector, pJCBD. The vector pJCBD expressed the fused protein named JCBD (M(r) 32 kDa) in E coli XL1-BLUE. The expressed JCBD protein was identified by Western blot analysis in the extract of the pJCBD carrying bacterial lysate using both rabbit anti-lambda phage antiserum and anti-CBD of fibronectin antibody. The JCBD protein appeared to recognize retinoblast cell membrane RGDS-directed receptors, detected by enzyme-linked immuno-sorbent assay and also by binding competition assay with synthetic pentapeptides, Gly-Arg-Gly-Asp-Ser (GRGDS) and Gly-Arg-Gly-Glu-Ser (GRGES). The former competitor inhibited completely fibronectin CBD-dependent binding activity of JCBD, the latter had no inhibitory activity. These results suggest that certain functional proteins engineered by computer design between human fibronectin cell binding domain and lambda phage J protein can be produced.

Amino Acid Sequence↗

Human cervical epidermal carcinoma-associated intracellular localization of glycosphingolipid with blood group A type 3 chain.

A monoclonal antibody, MRG-1, was produced by immunizing a mouse with a human ovarian mucinous cyst adenocarcinoma-derived cell line, RMUG-L. By immunohistochemical staining, the antigen was found to be exclusively localized in the intracellular structures of the cells used as the antigen and of the epithelial cells in normal human cervical glands. However, although the antigen was predominantly detected in the plasma membrane and the intercellular structure of the middle layer of normal human cervical squamous epithelium (92%), it was also contained in the intracellular structure of cervical epidermal carcinoma at a high frequency (80%). The striking difference in the distribution of the MRG-1 antigen between normal and cancerous tissues was found to be a cervical carcinoma-associated phenomenon and a useful tumor marker for immunohistochemical examination. Since the antigen was found to be of a blood group A-related nature by immunohistochemical staining of the tissues and to be a glycosphingolipid, it was purified from human erythrocytes of blood group A, and the structure was concluded to be GalNAc alpha 1-3Gal(2-1 alpha Fuc)beta 1-3GalNAc alpha 1-3Gal(2-1 alpha Fuc)-beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1' Cer, blood group A type 3 chain-containing glycosphingolipid, by NMR, negative ion FABMS and permethylation analysis. In the subcellular localization analysis of the antigen, type 3-A glycosphingolipid antigen was detected in the Golgi body and the microsomes of RMUG-L cells, and the distribution coincided with the finding by immunohistochemical staining. In addition, in cervical epidermal carcinoma, although the blood group A, mainly type 2-A chain, was localized in the plasma membrane and the intercellular structure, the blood group A type 3 chain was selectively found in the perinuclear structure. Also, the blood group A type 3 chain in cervical dysplasia as well as that in normal cervix was predominant in the plasma membrane. Thus, the selective intracellular localization of blood group A type 3 chain was a phenomenon characteristic of cervical epidermal carcinoma and the carcinoma in situ.

Animals↗

Pitting scars in progressive systemic sclerosis.

The digital pitting scar is a common clinical feature in patients with progressive systemic sclerosis (PSS). Its pathogenesis is unclear, but it may result in small ulcerations. The clinical and histological features of these lesions are poorly understood. Eighty-seven patients with PSS were examined at least once per year. Pitting scars were defined as pinhole-sized digital concave depressions with hyperkeratosis. They were seen in 34 cases (39%) and were located not only on the tips of the fingers, but also on the sides, especially on the radial border of the index and middle finger and the ulnar side of the thumb, where they had a linear arrangement. Additional pitting scars were noticed on the dorsal surface of the proximal interphalangeal and metacarpophalangeal joints. Pitting was closely associated with several signs of PSS, e.g. Raynaud's phenomenon, skin thickening or articular involvement (e.g. stiffness, swelling, pain). There was no relationship between the number of pitting scars and the duration of PSS. Biopsy samples were taken of the lesions on the lateral sides of fingers in 3 patients. Histologically, there was a plug-like hyperkeratosis with parakeratosis, homogenized collagen fibers and slight perivascular mononuclear cell infiltration. Calcification and altered collagen fibers were observed in the deep dermis. Although pitting scars of the fingertips may be different from those of the lateral sides of the fingers, both histologically and pathogenetically, they were similar clinically. The scar locations on the fingertips and finger joints (proximal interphalangeal and metacarpophalangeal) suggest that exogenous trauma, vibration injury and/or cold exposure may play a role in their pathogenesis.

Adult↗

Classification and relationships of rice strains with AA genome by identification of transposable elements at nine loci.

We analyzed the presence of p-SINE1 members at five loci in the rice strains belonging to seven species with AA genome in the Oryza genus by the methods including polymerase chain reaction (PCR). Four p-SINE1 members (p-SINE1-r3, r4, r5 and r7) were present at the corresponding loci in all the strains examined. One member (p-SINE1-r6) was, however, not present at the corresponding locus in most of the African strains of O. glaberrima and O. barthii, but was in the other strains. The PCR-amplified fragments containing p-SINE1-r4 in many strains were found to be larger due to insertion of either one of two transposable elements, named Tnr2 and Ret1, within or near p-SINE1-r4, respectively: Tnr2 is 157 bp in length with terminal inverted repeat sequences of about 56 bp; Ret1 is only 13 bp in length with a T stretch at its end. Tnr2 was not present in the corresponding locus in all the strains belonging to O. sativa Japonica and in some strains of O. rufipogon and O. longistaminata, while Ret1 was present only in the two strains of O. longistaminata. These results and previous ones obtained from the analysis of the other two p-SINE1 members (p-SINE1-r1 and r2) in the Wx gene indicate that the elements, such as p-SINE1-r6, Tnr2, Ret1 and p-SINE1-r2, have been inserted into the respective loci during divergence of the rice species with AA genome. The patterns for the presence and absence of the transposable elements at the respective loci enabled us to classify the rice strains with AA genome into ten groups and to infer their relationships.

Base Sequence↗

Identification of the soybean allergenic protein, Gly m Bd 30K, with the soybean seed 34-kDa oil-body-associated protein.

The soybean allergenic protein, Gly m Bd 30K [Ogawa et al., J. Nutr. Sci. Vitaminol., 37, 555-565 (1991)] which is most strongly and frequently recognized by the IgE antibodies in sera of soybean-sensitive patients with atopic dermatitis, has been characterized. The allergen was isolated from the crude 7S-globulin fraction as an oligomeric form with a molecular weight of more than 3000,000 by gel-filtration chromatography. On two-dimensional gel electrophoresis, the native oligomeric allergen had an isoelectric point of about pH 4.5 and was dissociated into a monomeric form with a molecular weight of about 32,000 by the treatment with sodium dodecyl sulfate and 2-mercaptoethanol. The monomeric allergen had an N-terminal amino acid sequence and amino acid composition identical with those of the soybean seed 34-kDa oil-body-associated protein or the soybean vacuolar protein P34 with close homology to papain-like thiol proteinases [Kalinski et al., J. Biol. Chem., 267, 12068 (1992)]. The identity was further confirmed by the immunological cross-reactivity to the antibodies produced against each of the purified allargen and the 34-kDa oil-body-associated protein. By this observation, Gly m Bd 30K was shown to have about 30% sequence homology with Der pI, a house dust mite allergen that is a thiol proteinase from Dermatophagoides pteronyssius.

Allergens↗

Amino-terminal location of pyridinoline in dentin collagen.

Cross-linking is believed to be one of the major factors that characterize the calcifiability of dentin and bone collagens. Dehydro-dihydroxylysinonorleucine and pyridinoline which constitute the principal cross-links of dentin collagen have so far been located only in the carboxy terminal telopeptide of the molecules [alpha 1(I)-chain 87 x alpha 1(I)-chain 16C]. This situation suggested that the amino terminal telopeptide portion might be "open" without intermolecular cross-linking in hard tissue collagen fibrils. However, the present study provided evidence that pyridinoline is also located in amino-terminal telopeptides (alpha 1-chain 9N or alpha 2-chain 5N) and alpha 1-chain 930. Bovine dentin collagen was digested with trypsin followed by heating at 60 degrees C before and after the digestion. This method gave complete trypsin peptides of dentin collagen. Fluorescent pyridinoline peptides with a smaller molecular size were isolated by Sephadex G-50 superfine, DEAE-cellulose and reverse-phase HPLC. Automatic Edman analysis of several isolated peptides revealed the five-residue sequence, Gly-Ile-X-Gly-His-Arg, the only assignment of which was alpha 1-chain 928-933. The above evidence together with the amino acid compositions of the peptides led to the conclusion that pyridinoline is located not only in the carboxy-terminal but also in the amino-terminal telopeptide in dentin collagen.

Amino Acid Sequence↗

Chest imaging with dual-energy subtraction digital tomosynthesis.

Dual-energy subtraction digital tomosynthesis with pulsed X-ray and rapid kV switching was used to examine calcifications in pulmonary lesions. The digital tomosynthesis system used included a conventional fluororadiographic TV unit with linear tomographic capabilities, a high resolution video camera, and an image processing unit. Low-voltage, high-voltage, and soft tissue subtracted or bone subtracted tomograms of any desired layer height were reconstructed from the image data acquired during a single tomographic swing. Calcifications, as well as their characteristics and distribution in pulmonary lesions, were clearly shown. The images also permitted discrimination of calcifications from dense fibrotic lesions. This technique was effective in demonstrating calcifications together with a solitary mass or disseminated nodules.

Humans↗

Athletes as health testing examinees.

Health-testing examination data of 91 male and 54 female athletes were studied, together with age-matched controls, on serum biochemistry, ECG findings, hematology, and some data on gynecological physiology. Analysis of serum biochemical values revealed statistically significant differences in 14 of 18 routine test items as compared with the age-matched controls. In ECG findings, the combination of bradycardia and left ventricular hypertrophy was most frequently found in male athletes, whereas that of bradycardia and sinus arrhythmia was observed predominantly in female athletes. The incidence of anemia and menstrual dysfunction was higher in female athletes than in controls, especially in the basketball team. In the same team, a high rate of deviant ECG records and a different distribution of the age at menarche were also observed.

Adult↗

Cellular fibronectin in plasma: its implications in fibrinogen-associated cryoprecipitation and other related reactions.

Elimination of cryoprecipitable plasma components (cryogels) by cryofiltration from the circulating blood of patients with drug-resistant rheumatoid arthritis (RA) alleviates clinical symptoms including morning stiffness and arthralgia. The cryogels thus isolated from the blood were found to consist mainly of fibrinogen (Fbg) and fibronectin (FN). Analysis by immunoblotting with an anti-cellular FN monoclonal antibody revealed that cellular FN (cFN) co-existed with plasma FN (pFN) in the cryogels derived from the patients. Using an ELISA, we assessed cFN together with the total FN (pFN+cFN) in plasmas and cryogels derived from the patients. The cFN/total FN ratio was distinctly higher in the cryogels than in the plasmas, suggesting that cFN was more readily precipitated than pFN in association with Fbg under cold conditions.

Arthritis, Rheumatoid↗

[Airway hyperreactivity test by measurement of specific airway conductance during quiet breathing].

In asthmatic patients, the threshold for specific airway conductance during quiet breathing (sGawqt) in the airway hypersensitivity test was determined using our newly developed pressure corrected flow type body plethysmograph and compared with that measured by means of respiratory resistance (Grs) Astograph in relation to the following parameters: 1) Dmin, an index of airway sensitivity (accumulated methacholine concentration at the time of onset of linear decrease in the dose-response curve), 2) SsGawqt and SGrs, indicators of airway sensitivity (slope when the value begins to decrease) and 3) PD35 (accumulated methacholine concentration when the valve has decreased to 35% of the initial value). Although no significantly difference was observed in SsGawqt and SGrs, significantly lower values of Dmin and PD35, indexes of airway sensitivity, were obtained with sGawqt method as compared to Astograph. These findings may indicate that the airway hypersensitivity test using our body plethysmography technique can be performed using a smaller amount of inhaled methacholine with less patient burden as compared to Astograph.

Adult↗