Biomedical subjects

S Shinoda

Publications and source records attributed to S Shinoda.

At least 91 records · Page 5Linked to original sources

PubMed1995

Differences in lymphocyte proliferative responses to food antigens and specific IgE antibodies to foods with age among food-sensitive patients with atopic dermatitis.

BACKGROUND: Clinical symptoms of patients with food-sensitive atopic dermatitis often improve with increasing age. OBJECTIVE: To investigate this tendency and the underlying mechanism. METHODS: We selected and divided 194 food-sensitive atopic dermatitis patients into three age groups. The proliferative responses of peripheral blood mononuclear cells (PBMCs) to food antigens and specific IgE antibodies to foods then were evaluated with respect to age. We also followed up 55 food-sensitive patients with atopic dermatitis and examined their improvement ratio after 1 year. Further, we investigated changes in lymphocyte proliferative responses to food antigens and specific IgE antibodies to foods in food-sensitive patients with atopic dermatitis during elimination diets. RESULTS: Proliferative responses of PBMCs to ovalbumin of patients in the over 6-years-old group were significantly (P < .05) lower than those of the less than 1-year-old group. Proliferative responses of PBMCs to bovine serum albumin of patients in the over 6-years-old group were significantly (P < .05) lower than those in the 1 to 5-year-old group and in the less than 1-year-old group. RAST values for hen egg in the over 6-years-old group were significantly (P < .05) lower than those for the less than 1-year-old group. Improvement was shown by 13 of the 33 hen egg-sensitive patients with atopic dermatitis, an improvement ratio of 39%, and by 9 of the 22 cow milk-sensitive patients with atopic dermatitis, an improvement ratio of 41%. Proliferative responses of PBMCs to food antigens in food-sensitive patients with atopic dermatitis decreased rapidly after patients were placed on elimination diets. CONCLUSION: The PBMC proliferative responses to food antigens and RAST values were higher for young children and lower for older ones who suffered from food-sensitive atopic dermatitis. Oral tolerance, in addition to the development of digestive and absorptive functions, may be responsible for these immunologic changes.

Adolescent↗

PubMed1994

Vibrio vulnificus may produce a metalloprotease causing an edematous skin lesion in vivo.

Vibrio vulnificus, an opportunistic human pathogen, secretes a metalloprotease which has been suspected of being the causative factor for edematous skin lesions. The antibody against alpha-macroglobulin, the sole plasma inactivator of V. vulnificus metalloprotease, delayed clearance of the protease administered into dorsal skin, and increased the edema-forming ability of living bacterial cells. The derivative of the protease, which is resistant to the inactivating action of alpha-macroglobulin, was not excluded from the dorsal skin. Furthermore, the vibrio inoculated into the mammalian serum was found to produce the protease in adequate amounts. These results suggest that V. vulnificus secretes a metalloprotease into the interstitial-tissue space, resulting in the development of an edematous skin lesion, and that the protease is immediately inactivated by alpha-macroglobulin and subsequently excluded.

Animals↗

PubMed1994

Purification and properties of Saccharomyces cerevisiae cystathionine beta-synthase.

Cystathionine beta-synthase (beta-CTSase), which catalyses cystathionine synthesis from serine and homocysteine, was purified to homogeneity from Saccharomyces cerevisiae. The molecular mass of the enzyme was estimated to be 235 kDa by gel filtration and 55 kDa by sodium dodecyl sulphate-polyacrylamide gel electrophoresis, indicating that it is a homotetramer. The N-terminal amino acid sequence of the enzyme perfectly coincided with that deduced from the nucleotide sequence of CYS4, except for the absence of initiation The purified beta-CTSase catalysed cysteine synthesis from serine (or O-acetylserine) and H2S. From this finding, we discuss the multifunctional nature and evolutionary divergence of S-metabolizing enzymes.

Amino Acid Sequence↗

PubMed1994

Structure of vulnibactin, a new polyamine-containing siderophore from Vibrio vulnificus.

A new siderophore named vulnibactin has been isolated from low iron cultures of Vibrio vulnificus, a human pathogen. The structure was established as N-[3-(2,3-dihydroxybenzamido)propyl]-1,3-bis[2-(2-hydroxy-phenyl)- trans-5 - methyl-2-oxazoline-4-carboxamido]propane by a combination of acid hydrolysis, nuclear magnetic resonance spectroscopy and positive fast atom bombardment mass spectrometry. Vulnibactin is characterized as containing one residue of 2,3-dihydroxybenzoic acid as well as two residues of salicylic acid, both of which are involved in the formation of oxazoline rings with L-threonine bound to a norspermidine backbone. In addition, two other compounds with siderophore activity were purified and their structures were also determined. These two compounds provided further support for the structure of vulnibactin.

Amides↗

PubMed1994

Proliferative responses towards native, heat-denatured and pepsin-treated ovalbumin by peripheral blood mononuclear cells from patients with hen's egg-sensitive atopic dermatitis.

In order to clarify the mechanism of food-antigen recognition, the proliferative responses of peripheral blood mononuclear cells (PBMCs) to native, heat-denatured or pepsin-treated ovalbumin (OA) were investigated in 16 hen's egg-sensitive patients with atopic dermatitis (AD). Seven of them had hypersensitivity to boiled hen's egg and others had not. The responses of PBMCs to heat-denatured OA were lower than those to native OA in the patients without hypersensitivity to boiled hen's egg. However, there were no differences of the responses of PBMCs between heat-denatured OA and native OA in the patients with hypersensitivity to boiled hen's egg. Moreover, the reduction of the responses of PBMCs to pepsin-treated OA was recognized in six out of seven patients. The primary structure of OA did not change by heating or pepsin treatment according to sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). These results suggested that the secondary structure of OA changed in connection with the reduction of the responses of PBMCs to denatured OA. In addition, we demonstrated the suppressive effect of anti-HLA-DR and anti-HLA-DQ monoclonal antibodies on the proliferative response of PBMCs to OA. The results suggested that the proliferative responses of PBMCs to OA were restricted by HLA-DR or HLA-DQ in hen's egg-sensitive patients with AD.

Antibodies, Monoclonal↗

PubMed1994

Predictive values of cord blood IgE and cord blood lymphocyte responses to food antigens in allergic disorders during infancy.

Proliferative response of cord blood lymphocytes stimulated twice by food antigens and cord blood IgE concentration were measured in 131 full-term newborn infants for the prediction of allergic disorders. Through the follow-up study for 2 1/2 years, the value of stimulation index in proliferative response of cord blood lymphocytes to ovalbumin or bovine serum albumin was greater than 1.5 in 17 (sensitivity 53.1%) of 32 infants in whom allergic disorders developed and less than 1.5 in 81 (specificity 81.8%) of 99 infants who had no allergic disorders (cutoff limit of stimulation index 1.5). The sensitivity was increased (71.9%) by the combination of the cord blood IgE concentration (cutoff limit 1.0 IU/ml) and proliferative response of cord blood lymphocytes to food antigens (cutoff limit of stimulation index 1.5). The combination of the cord blood IgE concentration and proliferative response of cord blood lymphocytes to food antigens is useful for the prediction of allergic disorders. Interleukin-2 production of cord blood lymphocytes stimulated with food antigens was also measured in 24 newborn infants. Interleukin-2 activity in culture supernatants of ovalbumin- or bovine serum albumin-stimulated cord blood lymphocytes correlated well with proliferative response of cord blood lymphocytes to ovalbumin or bovine serum albumin.

Antigens↗

PubMed1994

Structure and iron transport activity of vibrioferrin, a new siderophore of Vibrio parahaemolyticus.

The structure of vibrioferrin, a siderophore from Vibrio parahaemolyticus, was elucidated based on a combination of partial hydrolysis and spectroscopic techniques. HPLC of purified vibrioferrin showed two peaks with an area ratio of approximately 2:1. However, upon reinjection of each of those isolated compounds, the original chromatographic pattern was obtained, indicating an equilibrium between two compounds in aqueous solution. Consistent with this finding, most of the NMR signals of vibrioferrin were duplicated. The structure was determined as 1-(2-[2-(5-carboxy-5-hydroxy-2-oxo-1-pyrrolidinyl)propionamide]ethyl) citrate, which exists in two epimeric forms resulting from cyclization between an amidic nitrogen of the alanine residue and a keto group of the 2-ketoglutaric acid residue. Transport experiments with 55Fe-labeled vibrioferrin demonstrated the function of vibrioferrin as a siderophore in V. parahaemolyticus. Kinetic studies with mid-log phase cells revealed that the iron uptake system was receptor-mediated, with Km and Vmax values of 67 nM and 54 pmol Fe/mg cell protein/min, respectively. Moreover, iron uptake mediated by vibrioferrin was blocked both by uncouplers and by ATPase inhibitors.

Biological Transport↗

PubMed1994

Cloning and nucleotide sequence of the carboxynorspermidine decarboxylase gene from Vibrio alginolyticus.

The gene (nspC) encoding carboxynorspermidine decarboxylase (CANS DC), the last enzyme in norspermidine biosynthesis, in Vibrio alginolyticus was isolated by immuno-screening and its complete nucleotide sequence was determined. Sequence analysis of the subcloned fragment (2.0 kb) revealed an ORF of 1131 bp encoding a protein of 377 amino acids with a calculated molecular mass of 42,008 Da. The sequence of 20 N-terminal amino acids of purified CANS DC was found to be identical to that predicted from the nspC gene. A putative ribosome binding sequence was observed 8 bp upstream from the translation start site (ATG), and promoter- and terminator-like sequences were detected upstream and downstream of the ORF, respectively. Database searches identified no similar proteins, but the deduced amino acid sequence contained a putative pyridoxal 5'-phosphate binding region similar to those of the bacterial meso-2,6-diaminopimelate decarboxylases and eukaryotic ornithine decarboxylases. Another full ORF was found on the opposite strand downstream from the nspC gene. It encoded a protein of 69 amino acids with a calculated molecular mass of 7441 Da, which exhibited some weak similarity to ScrR, a repressor protein of V. alginolyticus, in the helix-turn-helix DNA binding domain, but did not appear to be expressed in the host cells.

Amino Acid Sequence↗

PubMed1994

Existence of a novel hemagglutinin having no protease activity in Vibrio mimicus.

The protease elaborated by Vibrio mimicus is known to possess hemagglutinating ability to chicken erythrocytes, the well-known HA/protease. A non-protease hemagglutinin (HA) with strong agglutinating ability towards rabbit erythrocytes was obtained from 32 hr culture supernatant of a pathogenic environmental strain of V. mimicus. This HA (V. mimicus HA: VMHA) appeared stable at relatively higher temperature and agglutinated the erythrocytes from rabbit, guinea pig and mouse but not the erythrocytes from chicken, bovine, horse and sheep. Simple sugars, metal ions and chelating agents failed to inhibit the activity of VMHA. The activity of VMHA was found to be sensitive to digestion by proteolytic enzymes including HA/protease. These results provide evidence for the existence of novel HA other than HA/protease in V. mimicus.

Animals↗

PubMed1994

Siderophore-mediated utilization of iron bound to transferrin by Vibrio parahaemolyticus.

Vibrio parahaemolyticus produces a structurally novel type of siderophore, termed vibrioferrin, in response to iron-limitation. This study was performed to examine whether vibrioferrin can assimilate iron from human iron-binding proteins for growth. Comparison of the growth rates between V. parahaemolyticus AQ 3354 and its spontaneously arising, vibrioferrin-deficient mutant revealed that vibrioferrin was able to sequester iron from 30% iron-saturated human transferrin for growth, but not from human lactoferrin even if fully saturated with iron. In both strains, iron limitation induced two high-molecular-weight outer membrane proteins with apparent molecular masses of approximately 78 and 83 kDa. Since only the outer membrane fraction including these proteins showed a binding capacity to ferric vibrioferrin complex, either of them may function as its cell surface receptor. These results suggested that the organism might utilize such a source of host iron through the action of vibrioferrin during in vivo survival and proliferation, although its importance in pathogenesis is unknown.

Bacterial Outer Membrane Proteins↗

PubMed1994

Identification of monocyte chemotactic factors in supernatants of ovalbumin-stimulated lymphocytes from patients with atopic dermatitis who are sensitive to hen's egg.

Monocyte chemotactic activities in supernatants of ovalbumin (OA)-stimulated peripheral blood mononuclear cell (PBMC) cultures were studied in patients with atopic dermatitis (AD) who were sensitive to hen's egg. The monocyte chemotactic activities in hen's egg-sensitive AD patients were significantly higher than those of non-atopic healthy controls and patients with immediate allergic symptoms. However, the monocyte chemotactic activities were not detected in bovine serum albumin-stimulated PBMC culture supernatants in patients with AD who were sensitive to hen's egg, but not to cow's milk. Furthermore, there was significant correlation between the monocyte chemotactic activities and proliferative responses of PBMCs to OA in hen's egg-sensitive AD patients, whereas there was no significant correlation between the monocyte chemotactic activities and radioallergosorbent test values. These results suggest that PBMCs stimulated with food antigens produce monocyte chemotactic factors which relate to the pathogenesis of AD in food-sensitive AD patients and that the pathogenesis of AD may be related to cell-mediated immune responses.

Adolescent↗

PubMed1994

Suppression of proliferative responses of lymphocytes to food antigens by an anti-allergic drug, ketotifen fumarate, in patients with food-sensitive atopic dermatitis.

Experimental studies have shown that ketotifen fumarate inhibits reaginic antibody-mediated hypersensitivity reactions. In this study, the proliferative responses of peripheral blood mononuclear cells (PBMCs) to ovalbumin (OA) in children with atopic dermatitis (AD), who are sensitive to hen's egg, were significantly higher than those of healthy children. The proliferative responses of PBMCs to OA were dose-dependently inhibited by ketotifen in patients with hen's egg-sensitive AD. Moreover, the inhibition resulted from the effects of ketotifen on T cells. In contrast, the proliferative responses of PBMCs to phytohemagglutinin and tetanus toxoid were not inhibited by ketotifen. These results suggest that ketotifen inhibits food antigen-specific proliferative responses of PBMCs in patients with food-sensitive AD.

Child, Preschool↗

PubMed1994

Timing of onset of allergic symptoms as a response to a double-blind, placebo-controlled food challenge in patients with food allergy combined with a radioallergosorbent test and the evaluation of proliferative lymphocyte responses.

The timing of onset of allergic symptoms in a double-blind, placebo-controlled food challenge (DBPCFC) was combined with a radioallergosorbent test (RAST) and evaluation of proliferative responses of peripheral blood mononuclear cells (PBMCs) in 27 atopic dermatitis patients with hen's egg allergy. Of the 27 patients, 11 showed reactions within 2 h (immediate group), and 16 showed reactions after more than 2 h (nonimmediate group) after ingestion of hen's egg. The RAST scores for hen's egg in the immediate group were significantly (p < 0.01) higher than those in the nonimmediate group, while the proliferative responses of PBMCs to ovalbumin in the nonimmediate group were significantly (p < 0.01) higher than those in the immediate group. These results suggest that the RAST values are related to immediate allergic symptoms in DBPCFC and the proliferative responses of PBMCs are related to nonimmediate allergic symptoms in DBPCFC. The timing of onset of allergic symptoms in DBPCFC will render DBPCFC more useful in the diagnosis of food allergy, including the late-onset reactions to foods.

Adolescent↗

PubMed1994

Relationship between cytosolic Ca2+ level and contractile tension in canine basilar artery of chronic vasospasm.

In order to study the role of the Ca2+/calmodulin/myosin light chain kinase system in the development of chronic vasospasm caused by subarachnoid hemorrhage, the cytosolic Ca2+ level ([Ca2+]i), measured with fura-2, a fluorescent Ca2+ indicator, and contractile tension were measured simultaneously, and their quantitative correlation was examined in basilar arterial tissue obtained from the canine "two-hemorrhage" model. Sixteen adult mongrel dogs were divided into two groups, control (n = 8) and vasospasm (n = 8), and were killed 7 days after the first experimental subarachnoid hemorrhage. In basilar arterial tissue loaded with fura-2, 1) [Ca2+]i in the resting condition was not significantly different between the two groups; 2) the increment in [Ca2+]i induced by 40 mmol/L K+ stimulation was significantly smaller in vasospastic tissue (P < 0.01); and 3) 40 mmol/L K(+)-induced tension development per cross-sectional area for a fixed increment in [Ca2+]i was significantly greater in vasospastic tissue (P < 0.01). In tissue not loaded with fura-2, active myogenic tone, which was tentatively represented by the ratio of tonus relaxed with 10(-4) mol/L papaverine to initial resting tone, was significantly greater in vasospastic tissue (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

Sensitization to sugar cane pollen in Okinawan allergic children.

Specific IgE antibodies to sugar cane pollen were investigated in seventy-four Okinawan children who suffered from allergic disorders. Only two (2.7%) with asthma of the 74 patients had specific IgE antibodies to sugar cane pollen as well as house dust and Dermatophagoides farinae. However, they have no histories of their symptoms being aggravated when sugar cane flowers bloom. From these results, the sensitization to sugar cane pollen exists in a small number of Okinawan allergic children, however, the low incidence of positivity could reflect lack of exposure to sensitizing doses of sugar cane pollen in these children.

Adolescent↗

PubMed1994

The design of oral sustained-release theophylline dosing after conversion from intravenous to oral therapy.

We studied the design of oral sustained-release theophylline dosing after conversion from constant aminophylline infusion. Twelve children with bronchial asthma (9 boys and 3 girls) were evaluated in this study. Each patient received a constant intravenous administration of aminophylline for 4-10 days. Three hours after conversion from constant aminophylline infusion, they received oral sustained-release theophylline twice daily at 12-hour intervals. Blood samples were obtained at least once during the aminophylline infusion, just before conversion from the aminophylline infusion, and 0, 3 and 6 hours, and 4-5 days after administering oral theophylline. Pharmacokinetic parameters were estimated using the serum theophylline concentrations that were obtained during constant aminophylline infusion. These estimates of pharmacokinetic parameters were used to predict the serum theophylline concentrations during oral theophylline therapy. Predicted serum theophylline concentrations using individual pharmacokinetic parameters were fitted with actual measured values in this study. When switching a patient from intravenous aminophylline to sustained-release oral theophylline, the use of Bayesian analysis of serum theophylline concentration values obtained during intravenous therapy works well in predicting serum theophylline concentrations and in determining oral dosages that maximize the drug's effectiveness.

Administration, Oral↗

PubMed1994

[Rhinogenous retrobulbar optic neuritis: a case report].

Rhinogenous retrobulbar optic neuritis is characterized by neuritis secondary to paranasal sinusitis. A case of rhinogenous retrobulbar optic neuritis that was successfully treated by surgery is reported. A 40-year-old man complained of progressive right visual disturbance. The clinical course and neurological examination suggested right retrobulbar optic neuritis. CT and MRI scans demonstrated a massive tumor-like lesion near the right optic canal. Fifteen days after the onset, decompression of the right optic nerve was performed using a right pterional approach. After surgery, visual disturbance improved, and after about 1 month, the symptom had disappeared. Operative findings, histological examination and the postoperative course were consistent with the characteristics of rhinogenous retrobulbar optic neuritis. We consider decompression of the optic nerve to be effective for the treatment of rhinogenous retrobulbar optic neuritis.

Adult↗

PubMed1994

Comparison of allergic diseases and specific IgE antibodies in different parts of Japan.

We investigated the differences of allergic diseases and specific IgE antibodies to inhaled or ingested allergens between two cities in a Japanese pediatric population. One of the two cities is Itoman, which is a subtropical city in Okinawa prefecture; the other is Gifu, which is a Temperate Zone city in Gifu prefecture. The prevalence of asthma or wheezy bronchitis was significantly higher in Itoman; however, the prevalence of atopic dermatitis was significantly higher in Gifu. Furthermore, the positive percentages of specific IgE antibodies to inhaled allergens such as house dust, and Dermatophagoides farinae were higher in Itoman. The positive percentages of specific IgE antibodies to ingested allergens such as egg white, cow milk, and soybean were higher in Gifu. These results suggest that the differences in prevalence of allergic diseases and allergens may depend on differences in the triggering environmental factors between different parts of Japan.

Administration, Inhalation↗