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K Kitada

Publications and source records attributed to K Kitada.

85 records · Page 5Linked to original sources
PubMed1988

Replication and maintenance of the Kluyveromyces linear pGKL plasmids.

Two new linear plasmids, pK192L (4.9 kb) and pK192S (2.4 kb), were isolated from a Kluyveromyces lactis killer strain carrying pGKL1 and pGKL2. pK192L was a deletion plasmid of pGKL1, derived from a part of the ORF1, and had a palindrome structure of a 215 bp unique sequence flanked by 2.35 bp inverted repeats. pK192S was a hairpin plasmid produced by self-annealing of a single-stranded pK192L DNA. In genetic analysis, pK192L and pK192S always coexisted and replicated in cells harboring pGKL2 and pGKL1, in contrast to other pGKL1-derived deletion plasmids, such as F1, F2 and pGKLIS, which could replicate in cells carrying pGKL2 only. Based on these and other lines of evidence, it was concluded that the reason for the pGKL1 dependent replication of the pK192L/S plasmids was the absence of the intact pGKL1-ORF1 gene and that the ORF1 function was necessary for the replication of the pGKL1 genome. This finding is in good agreement with a recent view reporting that ORF1 may encode a DNA polymerase of pGKL1. In a separate experiment, four new linear plasmids were isolated from a Saccharomyces cerevisiae strain carrying pGKL1 and pGKL2. Structural analysis showed that they consisted of two pairs of hairpin-palindrome type plasmids, each derived from different parts of pGKL2, respectively. pGKL1 stability replicated in cells carrying both these pGKL2 derived deletion plasmids.

Base Sequence↗
PubMed1988

Palindrome-hairpin linear plasmids possessing only a part of the ORF1 gene of the yeast killer plasmid pGKL1.

The yeast Kluyveromyces lactis harboring linear DNA plasmids pGKL1 and pGKL2 exhibits killer and killer-resistant phenotypes. Two new linear plasmids pK192L and pK192S were found in the weak killer mutant KUV192 induced by UV irradiation. pK192S was always accompanied by pK192L in subclones of KUV192. Both plasmids were derived from pGKL1 by deletion of the large right part of it. pK192L was 4.9 kb in size and had a palindromic structure consisting of 2.35 kb inverted terminal repetitions and a 215 base unique sequence. Analysis of denatured and renatured DNA strands suggested that pK192S was a hairpin-like form of pK192L. The pK192 plasmids were maintained only in cells haboring either pGKL1 or pGKL1Sin addition to pGKL2 and completed with pFKL1 or pGKL1S for their maintenance. Since no complete ORF1 was conserved in pK192 plasmids, these results lead to the conclusion that the ORF1 gene is necessary for the replication and/or maintenance of pGKL1.

Amino Acid Sequence↗
PubMed1988

Evidence for preferential multiplication of the internal unit in tandem repeats of the mating factor alpha genes in Saccharomyces yeasts.

We have determined DNA sequences of the mating factor alpha genes of Saccharomyces uvarum and Saccharomyces italicus and compared them to that of the MF alpha 1 gene of S. cerevisiae. The DNA sequences of the mating factor genes in both species were almost completely identical to that of the MF alpha 1 gene of S. cerevisiae except for the number of tandem repeated units; these latter consisted of a spacer peptide and a mature mating factor and there were three units in S. uvarum and five units in S. italicus compared with four units in the MF alpha 1 of S. cerevisiae. From the detailed comparison of DNA sequences of the spacer peptide-mating factor units from these three species, the high sequence homology can be recognized in the internal units of the tandem repeats. This suggests that the internal units might be multiplied preferentially in the tandem repeated units of mating factor genes.

Amino Acid Sequence↗
PubMed1987

A simple method for extraction of DNA from fungi and yeasts with anhydrous hydrogen fluoride.

A novel method is described for the extraction of DNAs from fungi and yeasts. Anhydrous hydrogen fluoride (HF) selectively cleaves their cell walls under mild conditions (for 5 min at 0 degrees C), enabling the effective extraction of DNAs from organisms with a cell wall. A possible mechanism for this method concerning the selective cleavage of O-glycosidic linkages in cell walls has been described previously [(1977) Anal. Biochem. 82,289-309]. The extracted DNA is intact: in fact, the yeast DNA is directly applicable for restriction analysis and transformation of Escherichia coli.

DNA Restriction Enzymes↗
PubMed1987

The role of preoperative intra-arterial doxorubicin chemotherapy in combination with low-dose irradiation for bladder cancer.

Twenty patients with bladder cancer (T1, 3 patients; T2, 6 patients; T3, 8 patients; T4a, 3 patients) were preoperatively treated with intra-arterial doxorubicin chemotherapy in combination with low-dose irradiation. The originally scheduled operations were as follows: total cystectomy in 16 patients (T1 + cis, 1 patients; T2, 5 patients; T3, 7 patients; T4a, 3 patients), segmental cystectomy in 2 patients, and transurethral resection in 2 patients. The total dose of doxorubicin ranged from 120 to 540 mg (251.5 +/- 100.2 mg), and that of irradiation was from 4 to 36 Gy (24.4 +/- 7.3 Gy). Clinical and pathological effects were evaluated in all of the cases. Clinically, complete remission (CR) was observed in 14 cases (70.0%), partial remission (PR) was seen in 3 cases, a minor response (MR) occurred in 2 cases, and no response (NR) was seen in 1 patient; non patient showed progressive disease (PD). The pathological effects (according to the criteria of Shimosato et al.) were as follows: grade IV was seen in 10 cases, grade III in 3 cases, and less than grade II in 7 cases; however, viable tumor cell were not seen in 13 (65.0%) of the 20 cases. The bladder was preserved in 13 (81.3%) of the 16 cases for which total cystectomy had been recommended. All of the patients were followed up for periods ranging from 3 to 54 months (26.3 +/- 16.5 months), during which time 6 patients (30.0%) died (3 with cancer, 1 without cancer, and 2 unknown causes). The actual survival rate according to the stage of disease was 100.0% at 50 months in T1-T2 and 40.9% at 54 months in T3-T4a. In T3-T4a, the actual survival rate in pathologically complete responders was 60% (relative rate 68.8%) at 54 months, and the actual survival rate in incomplete responders was 25.0% (relative rate 27.1%) at 36 months. The results of our study are encouraging, especially in T1-T2 and T3-T4a cases, who showed a complete response. It is concluded that doxorubicin intra-arterial chemotherapy combined with low-dose irradiation could be the first treatment of choice for locally invasive bladder cancer.

Aged↗
PubMed1982

High-performance liquid chromatographic determination of clioquinol and its conjugates in biological materials.

A method has been established for the determination of clioquinol (C) and its glucuronide (CG) and sulfate (CS) in biological materials. C and its internal standard were extracted with benzene-pyridine from samples. CG and CS were also hydrolyzed to C and extracted by the same method. The extracts were evaporated to dryness and redissolved in methanol. The methanol solution was subjected to HPLC using a column packed with Iatrobeads 6cp.2010 and a UV monitor (254 nm). The mobile phase was 0.1 M citric acid-methanol-n-hexane (8:86:6). The detection limit of C and 1 nmole and its recovery was above 92%.

Animals↗
PubMed1975

Combined cancer chemotherapy with cyclophoshamide and an inducer of microsomal drug-metabolizing enzymes (cytochrome P-450) in tumor-bearing rats.

The fifty percent alive period in Yoshida sarcoma-bearing and AH66F-bearing rats was prolonged by an administration in a single dose of 100 mg cyclophosphamide/kg body weight in a group pretreated with phenobarbital as compared with that pretreated with saline. However, there was little difference in fifty percent alive period between AH109A (insensitive to cyclophosphamide)-bearing rats and controls even when they were pretreated with phenobarbital. In chemotherapy with anti-cancer drugs, inductive or inhibitory effects of the drugs on microsomal drug-metabolizing enzymes should be taken into consideration.

Animals↗
PubMedDate not supplied

Epitope study and cDNA screening of major surface glycoprotein of Pneumocystis carinii.

Use of monoclonal antibodies against the major glycoprotein of Pneumocystis carinii (P115) implicated the sugar moiety as being strongly antigenic. Furthermore, monoclonal antibodies directed against the peptide portion of P115 were generated by using synthetic oligopeptides after amino acid sequencing was done on P115 proteolytic fragments.

Amino Acid Sequence↗
PubMedDate not supplied

Diagnosis of Pneumocystis carinii pneumonia by 5S ribosomal DNA amplification.

The polymerase chain reaction technique was used to detect Pneumocystis carinii by amplifying the P. carinii 5S ribosomal DNA. The efficacy and specificity of this diagnostic method is reported. Analysis of patients' sputa indicate that the method can be used on these samples for the diagnosis of P. carinii pneumonia.

Acquired Immunodeficiency Syndrome↗