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S Inouye

Publications and source records attributed to S Inouye.

At least 37 records · Page 2Linked to original sources
PubMed1992

Circumvention of multidrug resistance in human carcinoma KB cells by polyether antibiotics.

We examined the effect of various polyether antibiotics on colchicine resistance in multidrug-resistant KB-C4 cells which exhibit about 4,000-fold resistance to colchicine. As a result, 4 out of 14 polyether antibiotics were found to reverse colchicine resistance. Among them, laidlomycin was the most potent. It potentiated colchicine cytotoxicity on KB-C4 cells about 700-fold at 1 microgram/ml. Degree of potentiation was calculated by dividing of the IC50 value of colchicine in the absence of a polyether antibiotic by the IC50 value of colchicine in the presence of the polyether antibiotic. Monensin, dianemycin, and leuseramycin at 3 micrograms/ml also potentiated the cytotoxicity, about 100-fold. We previously reported that inostamycin is a potent chemosensitizer in KB-C4 cells. Although lysocellin has a structure very similar to that of inostamycin, it didn't reverse colchicine resistance. It slightly increased [3H]vinblastine accumulation in KB-C4 cells and weakly inhibited the [3H]vinblastine binding to KB-C4 plasma membranes.

Anti-Bacterial Agents↗
PubMed1992

Enteroviral aseptic meningitis in Japan, 1981-1991. A report of the National Epidemiological Surveillance of Infectious Agents in Japan.

In Japan, aseptic meningitis cases due to enterovirus infections increase every summer in various degrees with an incidence peak usually in July. During the past 11 years from 1981 through 1991, a total of 8,595 enterovirus isolations from aseptic meningitis cases were reported from 54 participating laboratories. Eight enterovirus types caused large epidemics; more than 100 isolations of each type from aseptic meningitis cases were reported for every epidemic year of the respective type. They were coxsackievirus (C) types B3 and B5, echovirus (E) types 4, 6, 7, 9, 18 and 30. Among these, the highest meningitis-associating frequency was reported for E30, representing 82.6% of the total isolations reported for the type during this period, followed by E4, 71.1%. The frequencies of E9, E7, E6 and CB5 were in a range from 54.5% to 44.4%, while that of E18 was 37.7% and that of CB3 21.0%. During the epidemics, enterovirus-associated meningitis was most frequently reported among children of 4-7 years of age. High frequencies were also shown in infants less than 1-year of age in some types. A total of 4,240 enteroviruses were isolated from cerebrospinal fluid of aseptic meningitis cases, representing 49.3% of the cases with enterovirus isolation.

Adolescent↗
PubMed1992

Poliovirus surveillance: isolation of polioviruses in Japan, 1980-1991. A report of the National Epidemiological Surveillance of Infectious Agents in Japan.

This report presents an overall distribution of poliovirus isolations in Japan, where poliomyelitis has been under control over two decades as a result of legal administration of two doses of the trivalent live oral poliovirus vaccine of the Sabin strains (OPV) to children under 48 months of age. During the past 12 years from 1980 through 1991, a total of 1,126 poliovirus isolations from humans and 268 isolations from sewage/river water were reported by respectively 49 and nine of the participating laboratories. Type 2 was most frequently isolated from children after administration of one dose of OPV, followed by type 1 and type 3. On the contrary, after the second dose of OPV, the rate of isolation of type 3 exceeded those of type 2 and type 1. Seasonal and age distribution of poliovirus isolations from both humans and sewage/river water paralleled the OPV vaccination schedule in Japan. One percent of the isolations were, however, from infants younger than the vaccination-scheduled ages and 5% were from children older than those ages, including one each from 15 and 16 years olds. The data indicate that the poliovirus has silently been disseminated from vaccinated children to others and the community, thus suggesting repeated transmission of the viruses. The fact that some elder children had poliovirus colonization in their alimentary tracts indicates a potential risk of infection of such a population when exposed to a wild virus and of becoming a source of transmission to others.

Adolescent↗
PubMed1992

Measurement of serum IgE antibodies against Japanese cedar pollen (Cryptomeria japonica) in Japanese monkeys (Macaca fuscata) with pollinosis.

IgE antibodies against allergens of Japanese cedar (Cryptomeria japonica, CJ) pollen in the serum of seven Japanese monkeys (Macaca fuscata) with pollinosis were measured by fluorometric indirect enzyme-linked immunosorbent assay (ELISA). All of the monkeys were found to have specific IgE to the crude pollen antigen. The specific IgE levels were well correlated with those determined by the Pharmacia CAP system. IgE antibodies were then assayed with two kinds of purified allergens (Cry j I and Cry j II) by the ELISA. We found that five monkeys had specific IgE to both allergens, although the other two had IgE only to Cry j I or Cry j II; there is different immune responsiveness to the two major allergens in the monkeys.

Allergens↗
PubMed1992

[A case of herpes simplex encephalitis diagnosed by polymerase chain reaction].

A case of a 55-year-old male with herpes simplex encephalitis (HSE) was reported. He was admitted because of fever, headache and memory disturbance. T1 weighted MRI showed low signal intensity and T2 weighted imaging revealed high signal intensity in the medial portions of bilateral temporal lobes. Herpes simplex virus (HSV) antibody titer in cerebrospinal fluid (CSF) was not elevated. HSV DNA in CSF was amplified by polymerase chain reaction (PCR) and identified by the microplate hybridization method. The PCR technique would be useful for the diagnosis of HSE.

DNA, Viral↗
PubMed1992

New hydroxybenanomicins produced by Actinomadura.

A soil microorganism, Actinomadura sp. MH193-16F4, produces an antifungal antibiotic benanomicin A and several related compounds. Among them, benanomicin A is the best candidate as a chemotherapeutic agent in terms of antifungal activity, toxicity and water-solubility. Three novel hydroxyl congeners, 3'-hydroxybenanomicin A, 7-hydroxybenanomicin A and 7-hydroxybenanomicinone have been isolated from the culture broth of the MH193-16F4 strain or its mutant. Interestingly, 3'-hydroxy-benanomicin A was as effective as benanomicin A, but the 7-hydroxy congeners were inactive. The inactive congeners differ from benanomicin A and 3'-hydroxyenanomicin A in their conformational structures at C-5 and C-6.

Anthracyclines↗
PubMed1992

[Brief counting method of airborne Cryptomeria japonica pollen by a combination of fluorescence antibody staining and flow cytometry].

Airborne pollens collected in a pollen collector (Virtual Impactor) was treated with a fluorescein isothiocyanate-labeled monoclonal antibody (KW-S10) which was strictly specific to Japanese cedar pollen antigen (Cry j I). Flow cytometric analysis revealed that the intensity of fluorescence of the pollen samples treated with the antibody was greater than that of non-treated reference pollen or the antibody treated Hinoki-cypress pollen. By use of this method, it may be possible to display the airborne pollen concentration within 20 min after sampling.

Air↗
PubMed1992

[Mechanisms of resistance to dactimicin and isepamicin in clinical strains of gram-negative rods isolated in Czechoslovakia].

Dactamicin is a new member of the pseudo-disaccharide group of antibiotics. It is structurally close to astromicin. Dactimicin is active against a wide variety of bacteria, including resistant strains with aminoglycoside-inactivating enzymes. Isepamicin is a broad-spectrum aminoglycoside, a derivative of gentamicin B. It is also active against many aminoglycoside-resistant strains. In a series of gram-negative bacterial isolates from various Czecho-Slovak regions, in vitro investigation yielded a good activity of dactimicin and isepamicin against amikacin- and gentamicin-resistant strains producing the enzyme AAC/6'/ or a combination of AAC/6'/ + ANT/2"/ enzymes. Dactimicin was not effective against strains producing the enzyme AAC/3/-I, and isepamicin was not effective or only slightly effective against bacterial isolates producing a combination of AAC/6'/ + AAC/3/ enzymes. (Tab. 3, Fig. 2, Ref. 10.).

Aminoglycosides↗
PubMed1991

A C-terminal proline is required for bioluminescence of the Ca(2+)-binding photoprotein, aequorin.

The requirement for a proline residue at the C-terminus of the Ca(2+)-binding photoprotein, aequorin, was investigated by measuring luminescence activities of a series of C-terminal deletion mutants, substitution mutants and an addition mutant. CD spectral measurements of apoaequorin with the C-terminal proline deleted showed a small change in secondary structure. In all cases studied, the C-terminal proline was required for bioluminescence activity.

Aequorin↗
PubMed1991

A gene encoding a protein serine/threonine kinase is required for normal development of M. xanthus, a gram-negative bacterium.

PCR reactions were carried out on the genomic DNA of M. xanthus, a soil bacterium capable of differentiation to form fruiting bodies, using oligonucleotides representing highly conserved regions of eukaryotic protein serine/threonine kinases. A gene (pkn1) thus cloned contains an ORF of 693 amino acid residues whose amino-terminal domain shows significant sequence similarity with the catalytic domain of eukaryotic protein serine/threonine kinases. The pkn1 gene was overexpressed in E. coli, and the gene product has been found to be autophosphorylated at both serine and threonine residues. The expression of pkn1 is developmentally regulated to start immediately before spore formation. When pkn1 is deleted, differentiation starts prematurely, resulting in poor spore production. These results indicate that the protein serine/threonine kinase plays an important role in the onset of proper differentiation.

Amino Acid Sequence↗
PubMed1991

Site-specific mutagenesis of human follistatin.

Follistatin is a monomeric protein originally discovered in ovarian follicular fluid as a suppressor of pituitary follicle-stimulating hormone (FSH) secretion, and later identified as a binding protein for activin. To explore the role of the Asn-linked carbohydrate chains on the follistatin molecule in regard to the inhibition of FSH secretion and activin binding ability, site-specific mutations were introduced at either or both of the two potential Asn-linked glycosylation sites of human follistatin with 315 amino acids (hFS-315). The three types of follistatin mutants were expressed individually in Chinese hamster ovary cells. When tested for their ability to inhibit FSH secretion and to bind activin, each mutant was found to have a similar property as the non-mutated recombinant hFS-315, suggesting that glycosylation of the follistatin molecule has no effect in these functions. However, a two amino acid insertion in between the second and the third amino acid residues in hFS-315 caused the resulting compound to lose completely its inhibitory activity on FSH secretion from the pituitary as well as its binding ability to activin. This finding suggests that the amino-terminal region of the follistatin molecule is critical for both of these functions.

Activins↗
PubMed1991

Nucleoside diphosphate kinase from Escherichia coli; its overproduction and sequence comparison with eukaryotic enzymes.

The gene encoding nucleoside diphosphate (NDP) kinase of Escherichia coli was identified by polymerase chain reaction using oligodeoxyribonucleotide primers synthesized on the basis of consensus sequences from Myxococcus xanthus and various eukaryotic NDP kinases. The gene (ndk), mapped at 54.2 min on the E. coli chromosome, was cloned and sequenced. The E. coli NDP kinase was found to consist of 143 amino acid residues that are 57, 45, 45, 42, 43, and 43% identical to the M. xanthus, Dictyostelium discoideum, Drosophila melanogaster, mouse, rat, and human enzymes, respectively. The ndk gene appears to be in a monocistronic operon and, when cloned in a pUC vector, NDP kinase was overproduced at a level of approx. 25% of total cellular proteins. The protein could be labeled with [gamma-32P]ATP and migrated at a 16.5 kDa when electrophoresed in SDS-polyacrylamide gel, which is in good agreement with the Mr of the purified E. coli NDP kinase previously reported.

Amino Acid Sequence↗
PubMed1991

Crystallization and preliminary X-ray diffraction analysis of oucleoside diphosphate kinase from Myxococcus xanthus.

Nucleoside diphosphate (NDP) kinase catalyzes the transfer of the gamma-phosphate from a nucleoside triphosphate to a nucleoside diphosphate. Human and rodent forms of this enzyme have been shown to be suppressors of metastasis. Crystals that diffract X-rays to high resolution have been obtained for the recombinant Myxococcus xanthus NDP kinase expressed in and purified from Escherichia coli. Two crystal forms have been obtained. Both forms are orthorhombic, space group I222 (or I2(1)2(1)2(1)) with a = 267.1 A, b = 74.0 A and c = 75.1 A for form I and a = 53.5 A, b = 74.0 A and c = 75.1 A for form II. Form I appears to have five molecules in the asymmetric unit approximately related to each other by a translation of 0.2 along the a axis. Diffraction data have been recorded to 1.9 A for form I and to 2.2 A for form II.

Crystallization↗
PubMed1991

Retronphage phi R73: an E. coli phage that contains a retroelement and integrates into a tRNA gene.

Some strains of Escherichia coli contain retroelements (retrons) that encode genes for reverse transcriptase and branched, multicopy, single-stranded DNA (msDNA) linked to RNA. However, the origin of retrons is unknown. A P4-like cryptic prophage was found that contains a retroelement (retron Ec73) for msDNA-Ec73 in an E. coli clinical strain. The entire genome of this prophage, named phi R73, is 12.7 kilobase pairs and is flanked by 29-base pair direct repeats derived from the 3' end of the selenocystyl transfer RNA gene (selC). P2 bacteriophage caused excision of the phi R73 prophage and acted as a helper to package phi R73 DNA into an infectious virion. The newly formed phi R73 closely resembled P4 as a virion and in its lytic growth. Retronphage phi R73 lysogenized a new host strain, reintegrating its genome into the selC gene of the host chromosome and enabling the newly formed lysogens to produce msDNA-Ec73. Hence, retron Ec73 can be transferred intercellularly as part of the genome of a helper-dependent retronphage.

Base Sequence↗
PubMed1991

Bioluminescent immunoassay using a monomeric Fab'-photoprotein aequorin conjugate.

The photoprotein aequorin emits light by an intermolecular reaction when mixed with Ca2+. To apply a bioluminescent immunoassay based on the light emission property of aequorin, we prepared aequorin-antibody Fab' conjugates by a chemical cross-linking technique. Recombinant apoaequorin was coupled with human tumor necrosis factor-alpha (TNF-alpha) antibodies (polyclonal Fab' or monoclonal Fab' fragments) using N-succinimidyl 4-(N-maleimidemethyl)cyclohexane-1-carboxylate. The luminescent activity of the Fab'-aequorin conjugate was about one-tenth that of aequorin. Using a monomeric conjugate, human TNF-alpha can be measured at an attomole level by a sandwich immunoassay technique.

Aequorin↗
PubMed1991

Retroelements in bacteria.

A peculiar type of satellite DNA, called msDNA, has been discovered in myxobacteria and some natural isolates of E. coli. These molecules are characterized by the presence of single-stranded DNA branching out from an internal guanosine residue of an RNA molecule by a unique 2',5'-phosphodiester linkage. Reverse transcriptase is required for the synthesis of msDNA. The discovery of retroelements in bacterial populations raises many intriguing questions concerning the evolutionary origin of reverse transcriptase, the function and the biosynthesis of msDNA, and the nature of the mechanisms generating the extensive diversity found in msDNA and reverse transcriptase genes among different bacterial strains.

Biological Evolution↗
PubMed1991

msDNA of bacteria.

The msDNA-retron element represents the first prokaryotic member of the large and diverse retroelement family found in many eukaryotic genomes (Table II). This prokaryotic retroelement exists as a single copy element in the chromosome of two different bacterial groups: the common soil microbe M. xanthus and the enteric bacterium E. coli. It encodes an RT similar to the polymerases found in retroviruses, containing most of the strictly conserved amino acids found in all RTs. The RT is responsible for the production of an unusual extrachromosomal RNA-DNA molecule known as msDNA. Each composed of a short single strand of RNA and a short single strand of DNA, msDNAs vary considerably in their primary nucleotide sequences, but all share certain secondary structural features, including the unique 2',5' branch linkage that joins the 5' end of the DNA chain to the 2' position of an internal guanosine residue of the RNA strand. It is proposed that msDNA is synthesized by reverse transcription of a precursor RNA transcribed from a region of the retron containing the genes msr (encoding the RNA portion) and msd (encoding the DNA portion) and the ORF (encoding the RT). The precursor RNA transcript folds into a stable secondary structure that serves as both the primer and the template for the synthesis of msDNA. The msDNA-retron elements of E. coli are found in less than 10% of all strains observed, are heterogeneous in nature, and have an atypical aminoacid codon usage for this species, suggesting that this element was transmitted to E. coli by some other source. The presence of directly repeated 26-base-pair sequences flanking the junctions of the Ec67-retron of E. coli also suggests that it may be a mobile element. However, the msDNA-retrons of M. xanthus appear to be as old as other genes native to this species, based on codon-usage data for the RT genes and the fact that every strain of M. xanthus appears to have the same type of msDNA. If the msDNA-retron element originated with the myxobacteria, it would place the existence of retrons before the appearance of eukaryotic cells, suggesting that the bacterial element is perhaps the ancestral gene from which eukaryotic retroviruses and other retroelements evolved.(ABSTRACT TRUNCATED AT 400 WORDS)

Base Sequence↗