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H Komatsubara

Publications and source records attributed to H Komatsubara.

12 recordsLinked to original sources
PubMed2005

A comparison of brachytherapy and surgery for the treatment of stage I-II squamous cell carcinoma of the tongue.

The treatment method for early stage tongue cancer is still controversial in Japan. The aim of this study is to compare the prognosis for patients with early tongue cancer treated with brachytherapy and surgery. A retrospective study was conducted to compare the efficacy of low-dose-rate brachytherapy (LDR), high-dose-rate brachytherapy (HDR), and surgery for early tongue cancer. A total of 180 patients with stage I-II tongue cancer were divided into three treatment groups: LDR (78), HDR (26), and surgery (71). Local recurrence was seen in thirteen patients (17%) of the LDR, nine (35%) of the HDR, and four (6%) of the surgery group. After salvage therapy, final local cure was obtained for 71 patients (91%) of the LDR, 22 (85%) of the HDR, and 71 (100%) of the surgery group. Neck failure was recorded for eight patients in the LDR, six in the HDR, and three in the surgery group. The respective 5-year overall survival rates for the LDR, HDR and surgery groups were 84.0%, 72.9%, 95.4% for stage I, and 72.2%, 51.5%, 93.8% for stage II. These findings show that surgery is the optimal treatment method for patients with stage I-II tongue cancer.

Adolescent↗
PubMed2002

Establishment and characterization of a human adenoid cystic carcinoma line of the salivary gland which is serially transplantable and spontaneously metastasises to the lung in nude mice.

Adenoid cystic carcinoma (ACC) is a rare malignant tumour of the head and neck occurring in the salivary glands. We established a human ACC line which is serially transplantable in nude mice and designated it as KOA-1. The KOA-1 tumour doubled in 9.3 days and retained the histological characteristics of a solid pattern of ACC even after 22 serial passages. The KOA-1 metastasised to the lung when transplanted subcutaneously into the back. This tumour line may serve as a useful model for exploration of the biological behaviour and treatment of human ACC.

Animals↗
PubMed2002

Evaluation of T-classifications of upper gingival and hard palate carcinomas--a proposition for new criterion of T4.

Most carcinomas of upper gingiva and hard palate are classified as T4 stage on the basis of the UICC criteria, since they easily invade the underlying bone tissue. We classified 43 patients with squamous cell carcinoma of the upper gingiva in terms of three criteria: (1) the original T-classification by UICC, (2) the classification by the Japan Society for Head and Neck Cancer (JSHNC), and (3) a new classification in which the maxillary sinus or nasal floor is used as the defining borderline for T4 (MSF classification). Our study demonstrated that the new classification was superior with regard to distribution of patients by T stage, correlation with prognosis and choice of treatment method.

Carcinoma, Squamous Cell↗
PubMed2000

High-dose rate interstitial brachytherapy for stage I-II tongue cancer.

OBJECTIVE: This retrospective clinical study evaluated the usefulness of high-dose rate (HDR) brachytherapy for stage I-II tongue cancer in comparison with traditional low-dose rate (LDR) brachytherapy. MATERIALS AND METHODS: Twenty-five patients with stage I-II tongue cancer underwent HDR between 1995 and 1999. The status of local control and late neck metastasis, survival rate, and frequency of osteonecrosis in these patients were examined in comparison with a historical control made up of 71 patients who underwent LDR between 1980 and 1995. RESULTS: The local control rate and survival rate were lower in the HDR group than in the LDR group. There were no apparent differences in the frequency of late neck metastasis between the two groups. Osteonecrosis occurred earlier and more frequently in the HDR group. CONCLUSION: We would caution the use of HDR brachytherapy until further studies are done in many institutions.

Brachytherapy↗
PubMed1996

Application of N-terminally truncated DNA polymerase from Thermus thermophilus (delta Tth polymerase) to DNA sequencing and polymerase chain reactions: comparative study of delta Tth and wild-type Tth polymerases.

N-Terminally truncated DNA polymerase from Thermus thermophilus (delta Tth polymerase) lacking 5'-3' exonuclease activity was used for DNA sequencing and polymerase chain reaction (PCR). In contrast to the high background of the sequencing ladder observed with the wild-type Tth polymerase, delta Tth polymerase gave readable sequencing patterns which extend up to more than 500 bases from the primer site on cycle sequencing and automated sequencing. The delta Tth polymerase was used for the standard and mutagenic PCR, and net amplification of the DNA and the mutations accumulated during PCR were analyzed. Under mutagenic PCR, the mutation rates were 7.0 x 10(-4) (Tth) and 8.3 x 10(-4) (delta Tth) per nucleotide per cycle of amplification, which were 4-9 times higher than the rates under standard PCR.

Automation↗
PubMed1994

Antigenic alteration of an anomalous human luteinizing hormone caused by two chorionic gonadotropin-type amino-acid substitutions.

We analyzed the nucleotide sequence of the luteinizing hormone beta subunit (LH beta) in a patient with an anomalous LH. This anomalous LH showed abnormal immunogenicity, but normal bioactivity, suggesting that this variance of antigenicity was caused by amino acid substitution(s). In the anomalous LH, two single amino acid substitutions, Trp(TGG) to Arg(CGG) and Ile(ATC) to Thr(ACC), were found at the codon for the 8th and 15th residue of LH beta. These two substituted amino acid residues of the anomalous LH are identical to those of chorionic gonadotropin, but not to those of LH, although the rest of the region showed the normal sequence of human LH beta. Pedigree analysis by direct DNA sequencing revealed that the parents of the patient and the healthy sister were heterozygotes for the mutation and the patient and the healthy brother were homozygotes.

Abortion, Habitual↗
PubMed1993

Synthesis and antiscorbutic activity of vitamin C analogue: L-threo-hex-2-enaro-1,4-lactone ethyl ester in the guinea pig.

L-threo-hex-2-enaro-1,4-lactone ethyl ester (II) was synthesized by the modified Fisher's esterification and its sodium salt was obtained almost quantitatively. Confirmation of the compound was made by elementary analysis, as well as IR, UV, MS and NMR spectra. The antiscorbutic activity was compared to that of ascorbic acid and the result showed that (II) did not have Vitamin C activity. The results of this investigation indicate that a close relationship exists between the chemical structure of the C-6 position of ascorbic acid analogues and the development of vitamin C activity.

Alkaline Phosphatase↗
PubMed1993

Genomic analysis of human hepatocellular carcinomas using Restriction Landmark Genomic Scanning.

Restriction Landmark Genomic Scanning (RLGS) was used to examine the multiple alterations of genomic DNAs that occur in association with transformation and development of malignancy in primary hepatocellular carcinoma (HCC). Genomic DNAs from HCC and its normal counterpart were cleaved by the restriction enzyme NotI, radiolabeled at the cleavage sites, and then size-fractionated by two-dimensional electrophoresis using HinfI as the second cleavage enzyme. About 2000 spots were recognized, whose position and intensity reflect the locus and the copy number of the corresponding restriction sites. Using this system in combination with micromanipulation of HCC to eliminate possible carry-over of nonmalignant cells, we detected six spots that were decreased in intensity in common to three different HCCs, along with five that were intensified spots. In addition, several spots showed changes that were nonoverlapping among different tumors.

Carcinoma, Hepatocellular↗
PubMed1992

New approach for detection of amplification in cancer DNA using restriction landmark genomic scanning.

We developed a new approach for detecting the gene amplification of cancer DNAs with restriction landmark genomic scanning (RLGS). In cancer research, much effort has been made to find the amplified loci of cancer DNAs, because many lines of evidence indicate association between oncogene amplification and carcinogenesis. Conventionally, such gene amplification has been detected by using Southern hybridization with DNA probes. However, only the information of one locus can be obtained by one hybridization procedure, and analysis of many loci throughout the genome is too laborious and time consuming, even if only several candidate genes are investigated. On the other hand, the "in-gel renaturation method" was reported as another alternative for detection of amplified regions. However, even though this method is much improved, it is difficult to detect less than 7-fold amplification, which is often higher than the amplification of many cancer cases. To overcome these limitations and, in addition, to locate the amplified DNA two dimensionally, we applied RLGS for analysis of DNA amplification in cancer tissues, such as breast cancer (infiltrative tubuloadenocarcinoma), neuroblastoma, meningioma (endotheliomatous meningioma), and thyroid cancer (papillary adenocarcinoma). In some cases of breast cancer, several amplified spots located on the same amplicon were detected. In thyroid cancer, in which no amplification has yet been reported, low-grade amplification was also detected. In this report, we demonstrated that RLGS allows us to screen 2000-3000 restriction landmarks distributed on the genome simultaneously, and even low-grade amplification could be detected effectively. Thus, RLGS has proven to be a very useful method in detecting DNA amplification.

Breast Neoplasms↗
PubMed1991

A genomic scanning method for higher organisms using restriction sites as landmarks.

We have developed a powerful genomic scanning method, termed "restriction landmark genomic scanning," that is useful for analysis of the genomic DNA of higher organisms using restriction sites as landmarks. Genomic DNA is radioactively labeled at cleavage sites specific for a rare cleaving restriction enzyme and then size-fractionated in one dimension. The fractionated DNA is further digested with another more frequently occurring enzyme and separated in the second dimension. This procedure gives a two-dimensional pattern with thousands of scattered spots corresponding to sites for the first enzyme, indicating that the genome of mammals can be scanned at approximately 1-megabase intervals. The position and intensity of a spot reflect its locus and the copy number of the corresponding restriction site, respectively, based on the nature of the end-labeling system. Therefore, this method is widely applicable to genome mapping or detection of alterations in a genome.

Animals↗
PubMed1991

Studies on the ascorbic acid 2-sulfate biosynthesis in rat.

The possible biosynthesis of ascorbic acid 2-sulfate (AsS) in rat was investigated. A in vivo test was conducted according to Mumma and Mohamram. 10 mumoles ascorbic acid (AsA) and 25 mu Ci35SO4(2-) were injected intraperitoneally into rats once a day for four days. 24 hours after the final administration, the animals were sacrificed and the liver, kidneys and urine were collected. The result did not confirm the biosynthesis of AsS under the test conditions, though there appeared the possibility of the biosynthesis of a trace amount of AsS too small to permit detection.

Animals↗