Search PubMed⌕ Search

Biomedical subjects

S Inouye

Publications and source records attributed to S Inouye.

At least 199 records · Page 11Linked to original sources
PubMed1994

A large outbreak of acute gastroenteritis associated with astrovirus among students and teachers in Osaka, Japan.

In June 1991, a large outbreak of acute nonbacterial gastroenteritis occurred among students and teachers at 10 primary and 4 junior high schools in Katano City, Osaka, Japan. The outbreak affected > 4700 persons, lasted 5 days, and was believed to have been linked to contaminated food from a common supplier. Astrovirus, identified as the etiologic agent, was detected by direct electron microscopy in 10 of 38 fecal samples obtained from patients with diarrhea. Detection was confirmed by solid-phase immune electron microscopy (IEM), EIA, reverse transcription-polymerase chain reaction, and virus isolation in CaCo-2 cells. Several patients who had astrovirus in their stool also demonstrated a significant antibody response to a reference strain of astrovirus by IEM and EIA and to their own isolate by IEM. Astrovirus can be an important agent of epidemic acute nonbacterial gastroenteritis in school-aged children and adults in Japan.

Acute Disease↗
PubMed1994

Analysis of DNA bend structure of promoter regulatory regions of xylene-metabolizing genes on the Pseudomonas TOL plasmid.

The transcription of both the upper operon (OP1) coding for m-xylene-degrading enzymes and the positive regulatory gene xylS on the TOL plasmid depends on sigma 54-RNA polymerase and requires the activator protein XylR that binds to the cis-acting upstream regulatory sequence of each promoter. For transcription of OP1 in Escherichia coli, integration host factor (IHF) is also required. IHF binds to DNA between the upstream regulatory sequence and the promoter sequence of OP1. We showed that IHF induced a DNA bend in the promoter regulatory region of OP1 upon its binding, supporting the DNA-loop model for the activation of OP1 transcription. In contrast to OP1, the transcriptional activation of xylS does not require IHF. In the absence of IHF, the promoter regulatory region of xylS promoter was shown to have a weak but significant intrinsic DNA bend, which may be involved in stabilizing the DNA-loop structure for the activation of xylS transcription. When IHF was highly produced in E. coli, the xylS transcription was repressed. We found two weak binding sites for IHF, each overlapping with the promoter sequence and the upstream regulatory sequence. The IHF binding to these sites might result in repression of xylS expression by overproduced IHF. Evidence is presented that binding of IHF to these sites induces a DNA bend.

Bacterial Proteins↗
PubMed1994

Estimation of Der p and Der f I quantities in the reference preparations of Dermatophagoides mite extracts.

A monoclonal antibody-based enzyme-linked immunosorbent assay (MoAb-ELISA) was developed to measure the major Dermatophagoides mite allergens, Der p I and Der f I. The assay was highly species-specific and sensitive. Using this assay system, the absolute mass unit of Der p I and Der f I in the reference preparations of the extracts was estimated. The primary standards used were the purified Der p I and Der f I preparations. The reference preparations of the D. pteronyssinus and D. farinae extracts (92-Dp and 92-Df), which had been prepared from the same amount of mite bodies of both species, were found to contain the same levels of the Der I allergens, 10.1 micrograms/ml of Der p I and 10.0 micrograms/ml of Der f I, respectively. A histamine release assay with leucocytes from mite-allergic donors showed that the total allergenic potency of 92-Dp and 92-Df was comparable. This results indicates that the estimated Der I levels in these extracts seem to be valid, at least, in the balance between the two species, although further comparisons of the absolute quantities by several different laboratories are needed. The Der I levels in the WHO/IUIS international reference preparation of D. pteronyssinus and the CBER standard mite extracts, E4-Dp and E5-Df, were also estimated using this assay system. They were found to contain 4.4 micrograms/vial and 13.3 micrograms/ml of Der p I and 9.5 micrograms/ml of Der f I, respectively.

Allergens↗
PubMed1994

Prevalence of IgE antibody to crude and purified allergens of Japanese cedar pollen among different troops of Japanese monkeys (Macaca fuscata).

We measured specific IgE antibodies to the crude allergen as well as two purified allergens (Cry j I and Cry j II) of Japanese cedar (Cryptomeria japonica--CJ) pollen in the serum of 276 Japanese monkeys in nine troops. Of 45 monkeys with CJ specific IgE in eight of nine troops, 23 (51%) were found to have IgE to both Cry j I and Cry j II, 21 (47%) only to Cry j I, and one (2.2%) only to Cry j II. The positive rate of specific IgE antibody to each allergen varied among the troops.

Allergens↗
PubMed1994

Identification of the gene encoding the major NAD(P)H-flavin oxidoreductase of the bioluminescent bacterium Vibrio fischeri ATCC 7744.

The gene encoding the major NAD(P)H-flavin oxidoreductase (flavin reductase) of the luminous bacterium Vibrio fischeri ATCC 7744 was isolated by using synthetic oligonucleotide probes corresponding to the N-terminal amino acid sequence of the enzyme. Nucleotide sequence analysis suggested that the major flavin reductase of V. fischeri consisted of 218 amino acids and had a calculated molecular weight of 24,562. Cloned flavin reductase expressed in Escherichia coli was purified virtually to homogeneity, and its basic biochemical properties were examined. As in the major flavin reductase in crude extracts of V. fischeri, cloned flavin reductase showed broad substrate specificity and served well as a catalyst to supply reduced flavin mononucleotide (FMNH2) to the bioluminescence reaction. The major flavin reductase of V. fischeri not only showed significant similarity in amino acid sequence to oxygen-insensitive NAD(P)H nitroreductases of Salmonella typhimurium, Enterobacter cloacae, and E. coli but also was associated with a low level of nitroreductase activity. The major flavin reductase of V. fischeri and the nitroreductases of members of the family Enterobacteriaceae would thus appear closely related in evolution and form a novel protein family.

Amino Acid Sequence↗
PubMed1994

Differentiation between wild and vaccine-derived strains of poliovirus by stringent microplate hybridization of PCR products.

Procedures for differentiation between wild and vaccine-derived strains of poliovirus are required, particularly in countries where wild and vaccine-related strains coexist. For this differentiation, we tested the method of Inouye and Hondo (S. Inouye and R. Hondo, Arch. Virol. 129:311-316, 1993) for discrimination of closely related viruses by using stringent microplate hybridization of PCR products. We used a pair of primers with enterovirus common sequences (between these primers there is a variable region for capsid proteins) for PCR using templates from wild and vaccine-derived poliovirus strains which were isolated in tissue culture and serotyped by neutralization assay. We also used the same primers for preparation of probes, which were labelled by incorporation of biotin-dUTP in the PCR, with the three original Sabin vaccine virus strains used as templates. The amplified DNAs from the isolates were immobilized on microplate wells and were then hybridized with the labelled probes. We found that, under the usual hybridization conditions, the Sabin vaccine virus strain probes hybridized with both wild and vaccine-derived viruses, but under stringent conditions, they reacted only with vaccine-derived viruses of the same serotype, clearly differentiating these from wild-type viruses.

Base Sequence↗
PubMed1994

Removal of cat major allergen (Fel d I) from futon (Japanese bedding) with a home washing machine.

We evaluated the removal of a cat major allergen (Fel d I) from futons (Japanese bedding) with the use of a large-sized home washing machine. Before and after washing a futon that had been used in a home with a cat, a small amount of cotton was collected from the futon and Fel d I was extracted from the cotton. The levels of Fel d I were assayed by a sandwich enzyme-linked immunosorbent assay (ELISA). We found that washing reduced the Fel d I level in futons by more than 95%. In conclusion, washing of futons is an effective method for elimination of their cat allergens.

Allergens↗
PubMed1994

Epidemics of aseptic meningitis due to echovirus 30 in Japan. A report of the National Epidemiological Surveillance of Infectious Agents in Japan.

Two rages of epidemic of aseptic meningitis (AM) due to echovirus 30 (E30) in Japan were analyzed with respect to two sources of information, AM incidence and E30 isolation, both gathered through the National Epidemiological Surveillance of Infectious Diseases. The first E30 epidemic spread throughout Japan in 1983 and ceased within the year. The second epidemic, starting in 1989, continued for the three successive years, and in the last year, 1991, the total E30 reports numbered 4,061, the largest number of a single virus type ever reported. Although the epidemic showed temporal and geographical shift and lasted for one or two years in some areas, most laboratories reported the largest number of E30 isolation in 1991. Among E30-yielding cases with clinical information during 1982-1992, the associating frequency with AM was as high as 82.5%. Other central nervous system involvements such as encephalitis, myelitis, encephalomyelitis and/or paralysis were reported in 36 E30-yielding cases and their monthly and age distributions were different from those of AM cases. The proportion of such disease among E30-yielding cases (0.60%) was close to that of other enteroviruses (0.56%). During the epidemics, E30 was isolated more frequently from cerebrospinal fluid than was E4 or E9 which prevailed coincidentally. E30 was most frequently isolated from cases of 4-7 years of age, sharing the common characteristic pattern of age distribution with other enteroviral meningitis. E30-yielding cases, however, involved a large number of older age groups than those of other enterovirus infections, and this tendency was the most pronounced in the first epidemic year, 1983. The contribution of these E30 epidemics on the yearly trend of clinically reported AM incidence and on the shift of its age distribution was also analyzed.

Adolescent↗
PubMed1994

Sensitization to cockroach allergens of asthma patients in Japan.

To evaluate the role of allergens from Periplaneta fuliginosa, which is the most predominant cockroach species in homes in Tokyo areas, for asthma sensitization, we measured specific IgE antibodies to two cockroaches, P. fuliginosa and Blattella germanica, and to a mite, Dermatophagoides farinae, in 171 sera from children with asthma by Pharmacia's CAP system. We found that 16% of the sera had anti-P. fuliginosa IgE, whereas 9.9% had anti-B. germanica and 85% anti-D. farinae IgE. Further, we measured the levels of Per f I (Per a I equivalent) allergen in the house dust from living room, kitchen and bedding. We detected the allergen in eight of ten homes. The Per a I equivalent levels in kitchen were higher than in other sites, but they were much lower than Der I and Der II as Dermatophagoides allergens.

Allergens↗
PubMed1994

[Effects of Celosia argentea and Cucurbita moschata extracts on anti-DNP IgE antibody production in mice].

We have already reported that the Perilla frutescens extract (PFE) suppressed anti-DNA IgE antibody production in mice. In this study, we prepared extracts of Celosia argentea L. (CAE) and Cucurbita moschata Duch (CME), which are Chinese herbal medicines like Perilla frutescens, and examined the effects on anti-DNP antibody responses in mice. To examine the effects of CAE & CME on primary antibody responses, CAE & CME were intraperitoneally injected the day before primary immunization of DNP-ovalbumin. Anti-DNP antibody production was markedly suppressed. Then, we examined the effects on secondary antibody responses. CEA & CME were injected only the day before secondary immunization. Anti-DNP IgE production was markedly suppressed, but IgG responses were not affected. It was also found that mitogenic activity occurred in CAE & CME dose dependently in vitro. These effects of CAE & CME were superior to that of PFE. These results suggest that CAE & CME may be more useful than PFE for the suppression of IgE antibody in certain allergic disorders.

Animals↗
PubMed1994

[Protracted (lasting) presence of Japanese cedar pollen allergen (Cry j I) in house dust].

We investigated the relationship between the amounts of Cry j I in house dust and airborne Cryptomeria japonica pollen in the same location. Cry j I was still detected in house dust collected two weeks after airborne C. japonica pollen had disappeared. Disappearance of Cry j I in house dust coincided with the disappearance of symptoms in the C. japonica pollinosis patients who lived in the same area. Airborne Cupressaceae pollen appeared during the latter half of the C. japonica pollen season. Disappearance of Cupressaceae pollen did not coincided with the disappearance of the symptoms in C. japonica pollinosis patients. Therefore, some symptoms of C. japonica pollinosis patients after C. japonica pollen disappeared from the air may be caused by pollen which had attached to clothes and been brought indoors.

Air Pollution, Indoor↗
PubMed1993

Crystal structure of Myxococcus xanthus nucleoside diphosphate kinase and its interaction with a nucleotide substrate at 2.0 A resolution.

The X-ray crystallographic structure of nucleoside diphosphate (NDP) kinase from Myxococcus xanthus has been determined using multiple isomorphous replacement techniques and refined at 2.0 A resolution to a crystallographic R-factor of 0.17. This is the first report of the structure of an enzymatically active NDP kinase and of the enzyme with a bound nucleotide. The structure has been determined in P4(3)2(1)2 and I222 crystal forms. The enzyme monomer consists of a four-stranded antiparallel beta-sheet. The surfaces of the sheet are partially covered with five helical segments. There are two protein molecules in the asymmetric unit of the tetragonal crystal form. They form a dimer with an extensive interface in which 1092 A2 per monomer is buried. The majority of the contact area in the dimer interface is between hydrophobic or aromatic residues. Two dimers are related by a crystallographic 2-fold axis to yield a tetramer. This tetramer is also present in the orthorhombic crystals; however, in this case, the 222 symmetry is entirely crystallographic. Upon tetramer formation, an additional 473 A2 of solvent-accessible surface area from each monomer becomes buried. The interface between dimers in the tetramer is stabilized by salt bridges. Equilibrium sedimentation studies are consistent with the enzyme being a tetramer in solution. The structure of a complex of adenosine diphosphate (ADP) with the enzyme was determined and reveals that most of the nucleotide interactions with the protein are with the pyrophosphate and ribose groups, while the base has no hydrogen bonds with the protein and interacts only by stacking with the side chain of Phe59. The Mg2+ interacts with the pyrophosphate of the ADP and via a solvent molecule with the side chain of the conserved Asp120 residue. The mode of interaction with the nucleotide is novel, with the nucleotide binding at the side of the beta-sheet. The structures of the nucleotide in crystals grown in the presence or absence of Mg2+ are essentially identical. In addition, the phosphotransfer reaction from adenosine triphosphate (ATP) to the enzyme can occur without Mg2+. This suggests that only the second step of the reaction in which the enzyme transfers the phosphate to a nucleoside diphosphate acceptor is significantly catalyzed by the metal.

Adenosine Diphosphate↗
PubMed1993

The relative rate of aequorin regeneration from apoaequorin and coelenterazine analogues.

The regeneration of an active semi-synthetic aequorin, from apoaequorin produced in cells and a coelenterazine analogue, is a key step in measuring Ca2+ in the cells. The relative rates of the regeneration of semi-synthetic aequorins from apoaequorin and 28 synthetic coelenterazine analogues were compared. The results indicated that the rate is strongly influenced by the analogues used. The regeneration of ordinary aequorin with normal coelenterazine was relatively fast (50% regeneration in 22 min), whereas the rates of regenerating semi-synthetic aequorins with coelenterazine analogues varied widely, and all were slower than that of regenerating ordinary aequorin, except for e-type coelenterazines (containing an extra ethano group). The regeneration with e-type coelenterazines was significantly faster, indicating the possible superiority of e-type analogues in the intracellular regeneration of aequorin, especially when an increased sensitivity to Ca2+ is needed.

Aequorin↗
PubMed1993

Cloning, expression and sequence analysis of cDNA for the Ca(2+)-binding photoprotein, mitrocomin.

The primary structure of mitrocomin consists of 190 amino acid residues, with three Ca(2+)-binding sites and a tyrosine residue at the C-terminus. Mitrocomin shows an amino acid sequence homology of 67.9% and 60.7% when compared with aequorin and clytin, respectively. The amino acid residues Cys152, His58, His169, Trp12, Trp86, Trp108, Trp129 and Trp173 are conserved in all three photoproteins, suggesting that they play a role in light emission.

Aequorin↗
PubMed1993

Reverse transcriptases from bacterial retrons require specific secondary structures at the 5'-end of the template for the cDNA priming reaction.

Multicopy single-stranded DNA (msDNA) is a peculiar molecule consisting of a single-stranded DNA that is branched out from an internal G residue of an RNA molecule (msdRNA) via a 2',5'-phosphodiester linkage. The genetic unit required for msDNA synthesis is designated "retron" and consists of msr (a gene for msdRNA), msd (a gene for msDNA), and a gene for reverse transcriptase (RT) in a single operon. To date, four different msDNAs have been isolated from Escherichia coli. They do not share any primary sequences in either RNA or DNA. To elucidate the specificity of bacterial RT for msDNA synthesis, the msr-msd region from retron-Ec67 was introduced into E. coli cells producing RT-Ec73, or the msr-msd region from retron-Ec73 into E. coli cells producing RT-Ec67. In both cases, msDNA was not synthesized. However, when the msdRNA coding regions (msr) for retron-Ec67 and -Ec73 were mutually exchanged and the chimeric genes were introduced into E. coli cells producing either RT-Ec67 or RT-Ec73, it was thus found that msDNA was produced only when msr and RT were from the same retron. Requirement of the msr region for msDNA synthesis by RT was further investigated by mutations in the msr region for retron-Ec67. These analyses revealed that there is a strict requirement for specific primary sequences as well as the secondary structure in msdRNA. This finding is discussed in relationship to the mechanism of the priming reaction of cDNA synthesis by eukaryotic retroviral RTs using tRNAs.

Bacterial Proteins↗
PubMed1993

Cloning and sequence analysis of cDNA for the Ca(2+)-activated photoprotein, clytin.

Clytin is a member of the aequorin family of photoproteins. It is made up of 189 amino acid residues, contains 3 Ca(2+)-binding sites, and shows 62% homology in amino acid residues to those in aequorin. The cysteine, tryptophan, and histidine residues, and the C-terminal proline, that are conserved in aequorin and clytin may be involved in the Ca(2+)-activated bioluminescence of the two proteins. Clytin may also prove useful in the determination of Ca2+.

Amino Acid Sequence↗
PubMed1993

Eukaryotic-like protein serine/threonine kinases in Myxococcus xanthus, a developmental bacterium exhibiting social behavior.

Myxococcus xanthus, a gram-negative bacterium exhibits a spectacular life cycle and social behavior. Its developmental cycle and multicellular morphogenesis resemble those of eukaryotic slime molds such as Dictyostelium discoideum. On the basis of this resemblance, we explored the existence of eukaryotic-like protein serine/threonine kinases which are known to play important roles in signal transduction during development of D. discoideum. It was indeed found that M. xanthus contains a large family of protein serine/threonine kinases related to the eukaryotic enzymes. This is the first unambiguous demonstration of eukaryotic-like serine/threonine kinases in the prokaryotes.

Amino Acid Sequence↗