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C Miyamoto

Publications and source records attributed to C Miyamoto.

At least 73 records · Page 4Linked to original sources
PubMed1990

Delineation of the transcriptional boundaries of the lux operon of Vibrio harveyi demonstrates the presence of two new lux genes.

The 5' and 3' ends of the lux mRNA of Vibrio harveyi, which extends over 8 kilobases, have been mapped, and two new genes, luxG and luxH, were identified at the 3' end of the lux operon. Both S1 nuclease and primer extension mapping demonstrated that the start site for the lux mRNA was 26 bases before the initiation codon of the first gene, luxC. The promoter region contained a typical -10 but not a recognizable -35 consensus sequence. By using S1 nuclease mapping the mRNA was found to be induced in a cell density- and arginine-dependent manner. The DNA downstream of the five known V. harveyi lux genes, luxCDABE, was sequenced and found to contain coding regions for two new genes, designated luxG and luxH, followed by a classical rho-independent termination signal for RNA polymerase. luxG codes for a protein of 233 amino acids with a molecular weight of 26,108, and luxH codes for a protein of 230 amino acids with a molecular weight of 25,326. The termination signal is active in vivo as demonstrated by 3' S1 nuclease mapping, confirming that the two genes are part of the V. harveyi lux operon. Comparison of the luxG amino acid sequence with coding regions immediately downstream from luxE in other luminescent bacteria has demonstrated that this gene may be a common component of the luminescent systems in different marine bacteria.

Amino Acid Sequence↗
PubMed1990

[Study of action spectrum of papulovesicular light eruption (PVLE)].

Eight patients suffering from papulovesicular light eruption (PVLE) were phototested for reproduction of skin lesions with FL20SE and FL20BLB. Of the 8 patients, 50.0% developed typical lesions of PVLE at the test site by provocative phototesting with FL20SE (3 daily exposure of 2MED). In these patients, similar lesions were induced by the provocative test with FL20BLB for 2 consecutive days without filter, but no eruptions were induced when a sharp cut filter UV-35 was used. In conclusion, it is important to consider not only UVB but also the border spectrum between UVB and UVA (320-340 nm) as the action spectrum of PVLE.

Adult↗
PubMed1989

Lux C, D and E genes of the Vibrio fischeri luminescence operon code for the reductase, transferase, and synthetase enzymes involved in aldehyde biosynthesis.

The lux C, D, and E genes of the Vibrio fischeri luminescence operon code for three polypeptides of 54, 33, and 42 kDa, respectively, which are required for synthesis of the aldehyde substrate for the luminescent reaction. These polypeptides have been identified in V. fischeri and V. harveyi as well as in recombinant E. coli harboring the cloned genes by specific acylation with [3H]fatty acid, showing that they are components of a fatty acid reductase system with reductase, synthetase and transferase activities. By using glycerol in the assay and/or extraction buffer and decreasing the reducing agent, the levels of the acylation of the 54 and 42 kDa polypeptides have been greatly increased. As a consequence, it was possible to demonstrate that the 54 kDa polypeptide coded by the lux C gene has reductase activity. In a subclone missing the lux E gene, the 42 kDa polypeptide was missing and the 54 kDa polypeptide could not be acylated in vitro with tetradecanoic acid (+ATP) and only to a low level in vivo indicating that the synthetase enzyme, responsible for fatty acid activation, is coded by the lux E gene. In vitro acylation with tetradecanoyl CoA of the 33 kDa polypeptide coupled with the specific cleavage of acyl-ACP only in E. coli extracts transformed with DNA containing the lux D gene, demonstrated that the lux D gene coded for the transferase enzyme.

Aldehydes↗
PubMed1989

Biological activities of synthesized 20K and 22K hGH in Nb2 bioassay and IM-9 radioreceptor assay.

We investigated the bioactivities of the recombinant DNA-derived methionyl 20K hGH (20K-Met-hGH) and methionyl hGH (22K-Met-hGH). The growth-promoting activities in Nb2 cells of 20K-Met-hGH and 22K-Met-hGH were 10.7% and 93.5% of pituitary hGH (P-hGH), respectively. In the IM-9 lymphocyte assay, the binding activities of 20K-Met-hGH and 22K-Met-hGH to hGH receptor were 29.0% and 87.1% of P-hGH, respectively. Our data demonstrate that 20K-Met-hGH may have weaker biological potency than P-hGH.

Animals↗
PubMed1989

Late onset of skin cancers in 2 xeroderma pigmentosum group F siblings and a review of 30 Japanese xeroderma pigmentosum patients in groups D, E and F.

Sib patients with xeroderma pigmentosum (XP), XP90TO (42 years old, male) and XP92TO (40 years old, female, were assigned to group F by the complementation analysis in hybridized heterodikaryons. The XP90TO and XP92TO fibroblasts exhibited the typical XPF characteristics of a threefold higher sensitivity to the lethal effect of 254 nm UV and a reduced level of 12% unscheduled DNA synthesis (UDS) compared with normal cells. Clinically, both patients manifested moderate to severe acute sun sensitivity by age 8, pigmented freckles by age 10 and skin malignancies at higher ages (6 basaliomas at 42 years in XP90TO; 1 basalioma at 41 years in XP92TO). Despite the still currently sun-sensitive state, the patients showed normal minimal erythema dose (MED) at monochromatic wavelengths of 290, 300 and 305 nm but abnormally delayed peaking of erythema reaction at 48 h after exposure. After irradiation with more than 3 MED, XP92TO showed a long persistence of induced erythema for at least 7 days. A review of the 16 reported XPF patients indicated mild skin manifestations, no neurological abnormalities, and more delayed skin carcinogenesis at a lower frequency than that in XPA patients. In addition, we have collected clinical information from Japanese XP patients in rare complementation groups D and E and reviewed their clinical and photobiological characteristics.

Adult↗
PubMed1989

Polymorphous light eruption: successful reproduction of skin lesions, including papulovesicular light eruption, with ultraviolet B.

Thirty patients suffering from polymorphous light eruption (PLE), selected by criteria pointing to UVB sensitivity, were phototested for reproduction of skin lesions. Twenty-seven patients (90.0%) had symptoms compatible with or very similar to papulovesicular light eruption (PVLE). Of the 30 patients, 56.7% developed typical lesion of PLE at the test site by provocative phototesting with UVB. Eruptions of the immediate onset type were apt to be reproduced by multiple repeated irradiation, but those of the delayed onset type were reproduced by a single high-dose exposure. In addition, pruritus at the test site seen in all patients was thought to be an important diagnostic symptom. It was obvious that UVB played an etiological role in PLE, including PVLE.

Adolescent↗
PubMed1988

A rapid and efficient purification of poly(A)-mRNA by oligo(dT)30-Latex.

Latex particles were covalently linked to the 5'-proximal region of oligo(dT)30. The resultant oligo(dT)30-Latex was tested for its hybridizability to poly(A) containing mRNA. Several advantages were noted as compared to the conventional oligo(dT)30-cellulose column chromatography; (1) a highly efficient (approximately 95%) hybridization occurs in a short reaction period (10min), (2) more than 95% of poly(A) mRNA can be recovered from oligo(dT)30-Latex by a simple heating followed by brief centrifugation, (3) multiple samples can be handled simultaneously and moreover, (4) the poly(A)-mRNA on the oligo(dT)30-Latex can be directly transcribed by AMV reverse transcriptase to form the cDNA. These properties of oligo(dT)30-Latex promise an excellent reagent for nucleic acid technology.

Chromatography, Affinity↗
PubMed1987

Hybridomas producing human monoclonal antibodies against varicella-zoster virus.

Hybridomas producing human monoclonal antibodies (mAb) against varicella-zoster virus (VZV) were generated by fusing human splenic lymphocytes with mouse myeloma cells. Before cell fusion, lymphocytes were stimulated in vitro with viral antigens and pokeweed mitogen. This combination synergistically increased the generation of VZV-specific hybridomas. Five established hybridomas have been stably producing mAb for at least 9 months. These mAb, designated V1, V2, V6, V8 and V9, were of the IgG1, lambda isotype. They bound to all 6 tested VZV strains but not to other herpes viruses, with the exception that V1 bound to herpes simplex virus (HSV) as well as VZV. Immunoprecipitation analysis showed that V1, V6 and V9 recognized glycoprotein gpII, whereas V2 and V8 recognized gpI. In addition, V1 reacted with the gB glycoprotein of HSV. All these mAb neutralized viral infectivity. The neutralizations by V2 and V8 were more effective and more complement dependent than those by V1, V6 and V9. Immunofluorescence tests revealed that all these mAb bound to the surface membrane of VZV-infected cells. These results suggest that cell fusion between in vitro stimulated lymphocytes and mouse myeloma cells is a reliable method for the generation of hybridomas capable of stable production of human mAb. The human mAb thus developed may provide a new means of passive immunization of humans against VZV infection.

Antibodies, Monoclonal↗
PubMed1987

Expression of bioluminescence by Escherichia coli containing recombinant Vibrio harveyi DNA.

When isogenic strains of Escherichia coli, RR1 (rec+) and HB101 (recA), were transformed with mapped recombinant plasmids known to contain Vibrio harveyi luciferase genes and large regions of DNA flanking on both sides, a small percentage (0.005%) of the colonies expressed high levels of luminescence (up to 10(12) quanta s-1 ml-1) in the absence of added aldehyde. The altered ability to express light was found to be due to a mutation in the host and not to an alteration in the recombinant DNA. When these bright colonies were cured of plasmid, they could be retransformed with cloned V. harveyi gene fragments in cis and in trans to yield luminescent colonies at 100% frequency. The maximum length of V. harveyi DNA required to produce light-emitting E. coli was shorter (6.3 kilobase pairs) than that required for expression of the V. fischeri system in E. coli. Cell extracts from bright clones contained wild-type levels of activity for the heteropolymeric (alpha beta) luciferase; fatty acid labeling revealed the presence of the three acylated polypeptides of the fatty acid reductase system which is involved in aldehyde biosynthesis for the luminescence reaction. The increased light emission in the mutant bacteria appeared to arise in part from production of higher levels of polycistronic mRNAs coding for luciferase.

Acylation↗
PubMed1986

Generation of hybridomas producing human monoclonal antibodies against human cytomegalovirus.

In vitro stimulation of human lymphocytes were studied in connection with cell fusion. When splenic lymphocytes were stimulated with human cytomegalovirus (CMV), they produced IgG but not IgM antibody against CMV. The stimulation with 50 ng/ml of CMV antigen induced the maximum antibody response, and higher concentrations of CMV antigen decreased antibody response and increased nonspecific IgG production. Human splenic lymphocytes were stimulated for 6 days with CMV antigen (50 ng/ml) and/or B-cell growth factor (BCGF), and then fused with mouse myeloma cells. Stimulation with a combination of antigen and BCGF were able to generate CMV-specific hybridomas synergistically. Two of these hybridomas were cloned by limiting dilution. The human monoclonal antibodies produced by them, C1 and C23, bound to CMV but not to other herpesviruses. C23 neutralized virus infectivity C1 did not at all. This method for generation of hybridomas producing human monoclonal antibodies against a predefined antigen may be applicable to a variety of viral antigens.

Antibodies, Monoclonal↗
PubMed1986

Concurrent multiple morphea and neonatal lupus erythematosus in an infant boy born to a mother with SLE.

An infant boy born to a mother with systemic lupus erythematosus developed multiple morphea and annular erythematous lesions. The annular lesions appeared on his face, back, chest and extremities one month after birth and faded within 7 months. The sclerotic lesions progressed until the age of 6 months and remain on his back, chest, right cheek, the nape of the neck and left shoulder at the age of 3 years. Histological findings in the sclerotic lesions were consistent with scleroderma. Serological tests, performed at 14 months of age, were within normal limits. The mother developed acute SLE and died of cardio-renal failure 8 months after the delivery. It is highly probable that maternal factors transferred through the placenta caused the sclerotic lesions in the infant.

Humans↗
PubMed1985

Molecular cloning and regulated expression of the human c-myc gene in Escherichia coli and Saccharomyces cerevisiae: comparison of the protein products.

mRNA from human HL-60 cells was used to prepare a cDNA library, from which two full-length clones that encompass the complete c-myc coding region were isolated. One clone, pM1-11, contains all three exons of human c-myc. The second clone, pM4-10, represents a relatively rare transcript that initiated in the first intron and includes the coding exons 2 and 3. The cDNA insert in pM1-11 was used to express the human c-myc protein in both prokaryotic and eukaryotic cells. Insertion of the coding sequences in exons 2 and 3 into the appropriate expression vectors yielded detectable c-myc protein in Escherichia coli lacking the Lon protease and in Saccharomyces cerevisiae upon induction. The protein produced in E. coli has an apparent size of 60 kDa and appears to be unmodified, as it is identical in size to the protein synthesized in an in vitro system. In contrast, yeast cells synthesize two myc proteins, of 60 kDa and 62 kDa. The difference in apparent molecular mass between the two proteins appears to be due, in part, to phosphorylation. Subcellular fractionation of yeast cells showed that the c-myc phosphoprotein is located predominantly in the nuclear fraction.

Base Sequence↗