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Biomedical subjects

T Miki

Publications and source records attributed to T Miki.

At least 937 records · Page 52Linked to original sources
PubMed1985

[VM-26 salvage therapy for refractory or recurrent germinal testicular cancers].

Four patients with refractory or recurrent germinal testicular cancers were treated with the combination of VM-26 and cis-platinum, and two of them also in combination with radiation therapy. Two complete responses and two partial responses were observed. One partial response was rendered no evidence of disease by sequential radiation therapy. Three of the patients remained to have no evidence of disease from 16, 21 and 22 months. Toxicity was tolerable. VM-26 is an active drug in germinal testicular cancers and plays an important role in salvage therapy, for refractory or recurrent cases.

Adult↗
PubMed1984

Control of cell division by sex factor F in Escherichia coli. I. The 42.84-43.6 F segment couples cell division of the host bacteria with replication of plasmid DNA.

The F plasmid of Escherichia coli was used to study the genetic background of the control circuit in the bacteria that co-ordinates DNA replication and cell division of the host cells. When DNA replication of the F plasmid was blocked by growing cells carrying an amber-suppressible replication-defective F plasmid mutant under restrictive conditions, the cells continued to divide for about one generation until F plasmid was supposedly diluted to one copy per cell, and then they stopped dividing and formed non-septated filamentous cells. These observations suggest that completion of a round of replication is a necessary and sufficient condition of F DNA synthesis in the cell division of F+ bacteria; i.e. cell division of the F+ bacteria is coupled with DNA replication of the F plasmid. The observation that Giemsa-stainable materials in the filamentous cells were clustered in the center indicates that partitioning of chromosomal DNA (and presumably of F plasmid DNA) is also coupled with plasmid DNA replication. The function necessary for this coupling is carried by the 42.84-43.6 F (BamHI-PstI) segment, which is located outside the region essential for replication of the F plasmid. The nucleotide sequence demonstrates the existence of two open reading frames in this region, which encode polypeptides of 72 and 101 amino acids, respectively. These two reading frames are most likely to be transcribed as a single polycistronic message in the direction from the BamHI site at 42.84 F to the PstI site at 43.6 F. The expression of this "operon" is likely to be controlled by plasmid DNA replication.

Base Sequence↗
PubMed1984

Control of cell division by sex factor F in Escherichia coli. II. Identification of genes for inhibitor protein and trigger protein on the 42.84-43.6 F segment.

The genetic structure of the 42.84-43.6 F (BamHI-PstI) segment of the F plasmid, which contains all the F DNA sequences necessary for coupling cell division of F+ bacteria with plasmid DNA replication, was analyzed by isolating a series of amber mutants. Two cistrons were found in this region and they were designated letA and letD (an abbreviation for lethal mutation). The letA and letD cistrons were mapped on the 42.84-43.35 F (BamHI- XmaI ) segment and the 43.07-43.6 F (HincII-PstI) segment, respectively, and are presumed to correspond to the first (43.04-43.26 F) and second (43.26-43.57 F) open reading frames, respectively, which were found in this region by nucleotide sequencing. The letD gene product acts to inhibit cell division of the host bacteria and to induce prophages in lysogenic bacteria, whereas the letA gene product acts to suppress the activity of the letD gene product. Taking into consideration the fact that the 42.84-43.6 F segment carries all the F plasmid genes necessary for coupling cell division with plasmid DNA replication, and that the expression of the genes is likely to be controlled by plasmid DNA replication, we constructed the following hypothesis. Before completion of plasmid DNA replication, LetD protein acts to prevent cell division of the host bacteria. When plasmid DNA replication is completed, synthesis of LetA protein (and also LetD protein) takes place and the LetA protein synthesized acts to suppress the activity of LetD protein and make the cell ready for cell division. Actual cell division will take place when replication of both chromosomal and plasmid DNA is completed and the termination protein of the chromosome and the LetA protein of F plasmid are both synthesized. When cell division takes place LetA protein is consumed, and as a result LetD protein becomes active and prevents cell division until the next round of DNA replication is completed.

Bacteriophage lambda↗
PubMed1984

Transcription analysis of the lexA gene of Escherichia coli: attenuation and cotranscription with the neighboring region.

The lexA gene of Escherichia coli encodes a repressor of the genes whose expression is induced by the agents that result in DNA damage. In vivo transcripts of the lexA gene consisted of two species; mRNA-1 of 673 bases and mRNA-2 of approximately 3,000 bases. The transcription in vivo started at a site which was two-base pairs downstream from the in vitro initiation site reported previously. The majority of the transcription stopped at a series of T residues preceeded by a dyad symmetry located immediately after the lexA gene. A small fraction of the transcription passed through the termination site to form the mRNA of downstream gene(s) which would be related to the "SOS functions".

Bacterial Proteins↗
PubMed1984

DNA sequence of an amber replication mutant indicates that a 29 kd protein is the product of the F plasmid replication gene.

DNA sequencing shows that the mutational alteration resulting from an amber-suppressible replication-defective mutation of F plasmid is a single base pair change from C:G to T:A which yields an amber codon in the coding frame for a 29 kd polypeptide located in the minimal replication region. We thus identified the gene indispensable for F DNA replication as the coding frame which encodes a 29 kd polypeptide. We will designate this gene repA.

Base Sequence↗
PubMed1984

Cross-sensitivity between interferon and uv in human cell strains: IFr, HEC-1, and CRL1200.

Correlation between susceptibility to the anticellular effect of human interferon (HuIFN) and ultraviolet (uv) lethality was examined in a set of isogeneous human cell lines (RSa and IFr cells), a human endometrial cancer cell line (HEC-1 cells), and a Xeroderma pigmentosum-derived fibroblast cell line ( CRL1200 cells). IFr cells, previously established as a HuIFN-alpha-resistant subline by exposing HuIFN-alpha- and uv-sensitive RSa cells to HuIFN-alpha preparations, appeared more refractory to uv than did the parent RSa cells in the cell proliferation and colony-formation studies. The extent of recovery from uv-inhibited total cellular DNA synthesis and uv-induced DNA-repair synthesis was enhanced to a greater extent in IFr cells than in RSa cells. The preexposure of RSa cells to HuIFN-alpha enhanced uv-induced DNA-repair replication activities. HEC-1 cells, which are reportedly totally refractory to HuIFN actions, appeared most resistant to uv, in all the tests. The uv-sensitive CRL1200 cells appeared highly susceptible to HuIFN-beta, in both cell proliferation and DNA-synthesis inhibition tests. These results support and extend our previous finding (N. Suzuki, J. Nishimaki , and T. Kuwata (1982). Mutat . Res. 106, 357-376) that susceptibility to the anticellular effect of HuIFN closely relates with uv lethality.

Cell Division↗
PubMed1984

Expression of the anti-retrovirus action of interferon in human cells which exhibit a reduced number of receptors for interferon.

The anti-viral and anti-cell fusion actions of human gamma interferon (IFN) were examined on human rhabdomyosarcoma cells and compared with the actions of IFN-alpha. Treatment of A204 and RD114-C1 cells with IFN-gamma resulted in significant inhibition of retrovirus production and cell fusions which were induced by Sendai virus, but IFN-gamma did not induce 2'-5' oligoadenylate (2-5A) synthetase or dsRNA-dependent protein kinase, and failed to inhibit EMC virus replication in RD114-C1 cells as previously observed on IFN-alpha treatment (Tomita, Y. et al. (1982) Virology 120, 258-263). Although IFN-gamma induced 56K protein more strongly than IFN-alpha in human transformed HEp-2, HeLa, RSa, IFr, and A204 cells, no significant induction of this protein was observed in RD114-C1 cells after IFN-alpha or IFN-gamma treatment. Specific bindings of 125I-labeled human IFN-alpha A to HeLa, A204 and RD114-C1 cell surfaces showed that the numbers of the binding sites on RD114-C1 cells were reduced to less than 22% of those on A204 cells. These results suggest that RD114-C1 cells exhibit a reduced number of receptors for IFN on the cell surface and that the receptors are functional for the expression of the anti-retrovirus and anti-cell fusion actions of IFN, but are not enough in number for expression of the anti-EMC virus action of IFN.

Antiviral Agents↗
PubMed1984

Heterogeneity of Sindbis virus glycoprotein E1 and its modification by host cell transformation.

The electrophoretic properties of glycoprotein E1 of Sindbis virus grown in Rous sarcoma virus-transformed cells were compared with those of Sindbis virus grown in untransformed cells. Isoelectric focusing in a gel containing 9.5 M-urea and 2% Nonidet P40 indicated that the glycoprotein E1 of Sindbis virus from the untransformed cells was electrochemically heterogeneous and consisted of four components, whose isoelectric points (pIs) ranged from 6.2 to 6.7; the E1 of Sindbis virus from the transformed cells contained an additional component with a pI of 6.1. After treatment with neuraminidase the observed charge heterogeneity disappeared regardless of whether the virus had come from the transformed or the untransformed cells. The five components were digested with Pronase and compared by gel filtration on Bio-Gel P-6; the four components with relatively higher pIs released high-mannose-type and complex-type oligosaccharides which differed in their content of sialic acid. In contrast, the pI 6.1 component, which existed only in the transformed cell-derived SV glycoprotein E1, released only complex-type oligosaccharide. These results indicate that the properties of glycoprotein E1 derived from both cell types are basically similar but that a small proportion of the E1 molecules from the transformed cells, with carbohydrate chains elongated by attachment of sialic acid residues, lacks simple-type oligosaccharides either because they are not attached or because they have been processed to the complex type. Glycoprotein E2 appeared as at least three components in non-equilibrium pH gradient electrophoresis. However, no significant difference was observed between the cell types.

Animals↗
PubMed1984

Nucleotide sequence of the phoS gene, the structural gene for the phosphate-binding protein of Escherichia coli.

phoS is the structural gene for the phosphate-binding protein, which is localized in periplasm and involved in active transport of phosphate in Escherichia coli. It is also a negative regulatory gene for the pho regulon, and the gene expression is inducible by phosphate starvation. The complete nucleotide sequence of the phoS gene was determined by the method of Maxam and Gilbert (A. M. Maxam and W. Gilbert, Methods Enzymol. 65:499-560, 1980). The amino acid sequences at the amino termini of the pre-PhoS and PhoS proteins and at the carboxy terminus of the PhoS protein were determined by using the purified proteins. Furthermore, the amino acid sequence of enzymatically digested peptide fragments of the PhoS protein was determined. The combined data established the nucleotide sequence of the coding region and the amino acid sequence of the pre-PhoS and the PhoS proteins. The pre-PhoS protein contains an extension of peptide composed of 25 amino acid residues at the amino terminus of the PhoS protein, which has the general characteristics of a signal peptide. The mature PhoS protein is composed of 321 amino acid residues, with a calculated molecular weight of 34,422, and lacks the disulfide bond and methionine. The regulatory region of phoS contains a characteristic Shine-Dalgarno sequence at an appropriate position preceding the translational initiation site, as well as three possible Pribnow boxes and one -35 sequence. the nucleotide sequence of the regulatory region of phoS was compared with those of phoA and phoE, the genes constituting the pho regulon.

Amino Acid Sequence↗
PubMed1984

[Bronchial asthma due to inhaled chloroplatinate].

Platinum and its compounds have characteristics that make them excellent oxygen sensors, and in recent years they have come to be used in large amounts in the manufacture of internal combustion engines. Recently, there have been detected among workers engaged in making platinum oxygen sensors, dermatitis and bronchial asthma which appear to be ascribable to exposure to chloroplatinate. This is a study of their etiology from the viewpoint of industrial hygiene and clinical medicine. The results obtained are as follows: Platinum-induced allergic disorders developed in a worker who applies about 50% chloroplatinate to zirconia porcelain. Although the concentration of platinum in the air was 2 microgram/m3 or less as determined by ACGIH, the worker was directly exposed to the dried powder of ammonium chloroplatinate with relatively high concentration; while the exposure was intermittent and topical, it resulted in aspiration of the powder. Bronchial asthma observed in 2 of 16 workers (12.5%) was reactive in a skin drop test with 1% chloroplatinate, and typical bronchial asthma was induced in an environmental provocation test carried out in a room where platinum sensors are made. Parameters obtained from periphero-hematological and immuno-serological tests were within the normal range. The main symptoms revealed by physical examination of workers exposed to chloroplatinate contact dermatitis in 11 (78.6%), pharyngeal irritation in 6 (42.9%), nasal obstruction in 2 (14.3%), frequent sneezing, coughing, and sputum in one each.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

[Clinical evaluation of ceftizoxime in the treatment of complicated urinary tract infections].

Ceftizoxime (CZX) was given clinically to 80 patients with urogenital tract infections, in which 34 cases of complicated UTI satisfied the criteria of the UTI committee. CZX was administered for at least five days at a daily dose of 1 to 4 g in two divided doses by intravenous drip infusion. The overall clinical efficacy of CZX in 34 cases of complicated UTI was 59%, estimated by the criteria of the UTI committee. The overall clinical efficacy rate according to group of infection was: 64% for the 11 patients in the 1st group, 56% for the 9 patients in the 2nd group, 100% for the 5 patients in the 3rd group, 50% for the 4 patients in the 4th group and 20% for the 5 patients in the 5th group. No serious side effects were observed in the clinical or laboratory findings except for slight elevation in GOT & GPT values in two cases (2.5%), which returned to normal after CZX treatment. It is therefore suggested that CZX is a clinically useful and safe drug in the treatment of complicated UTI.

Adolescent↗
PubMed1984

[A case of vesical malacoplakia].

A 44-year-old woman was admitted to our hospital, complaining of terminal hematuria. On cystoscopy four yellow and soft nodular masses were observed in the bladder, one of which had central ulceration. TUR was performed for these masses. Histological examination revealed that they were vesical malacoplakia. The masses consisted of aggregates of macrophages with abundant cytoplasma in which typical Michaelis-Gutmann bodies were demonstrated by light and electron microscopies.

Adult↗
PubMed1984

[Clinical management of testicular tumors].

Testicular tumor is a rare diseases in Japan. The incidence, histology, staging, tumor markers, treatment, and prognosis of this diseases are reviewed. Recently dramatic changes have occurred in the management of the disease, resulting in substantial improvement in ultimate survival. Many developments in chemotherapy, particularly the introduction of cis-platinum, have been largely responsible for this dramatic improvements in treatment and prognosis. Therapy depends a large extent upon the histological type and stage of the tumors, including tumor markers. Surgical excision of primary tumors followed by combination chemotherapy is primary mode of treatment in advanced testicular tumor cases. Standard chemotherapy for advanced tumors involves either cis-platinum, vinblastine, and bleomycin (PVB), or the above 3 drugs combined with actinomycin-D and cyclophosphamide (VAB-6). These regimens have produced complete remission rates of 50%-77% and improved the frequency of long-term survival. The treatment goal for this disease is cure. The achievement of disease free status, with aggressive combined chemotherapy and surgery or radiation is essential for reaching this goal.

Antineoplastic Combined Chemotherapy Protocols↗