Search PubMed⌕ Search

Biomedical subjects

T Kondoh

Publications and source records attributed to T Kondoh.

At least 163 records · Page 9Linked to original sources
PubMed1993

5' structure and expression of human glucose-6-phosphate dehydrogenase mRNA.

The human glucose-6-phosphate (G6PD) cDNAs cloned from normal and carcinoma cells can encode 545-amino-acid residues starting from the first in-frame chain initiation codon. However, it was reported that the G6PD mRNAs of carcinoma cell lines were shorter and could encode only 515-amino-acid residues (Martini et al., 1986). We demonstrated the existence of two major G6PD mRNAs in normal reticulocytes, lymphoblasts, and hepatocytes by the primer extension analysis. The longer mRNA has a cap site at approx. nucleotide -166 and can encode 545-amino-acid residues, whereas the shorter mRNA has a cap site at approx. nucleotide -66, and encodes 515-amino-acid residues. These two naturally existing mRNAs (cDNAs) and an artificially truncated mRNA, which can encode the carboxy-terminal 479-amino-acid residues of the subunit, were expressed in the in vitro reticulocyte and wheat germ systems and in the in vivo E. coli system. All three species of mRNA (cDNA) were efficiently translated and produced proteins with the expected molecular sizes. The peptide with 515 residues formed the catalytically active enzyme, but the 545-residue protein and the 479-residue protein were catalytically inactive. The larger 545-residue protein may correspond to the larger G6PD precursor observed in the rat. The extended amino-terminal region encoded by the larger mRNA contains the -Arg-Gly-Gly-Arg-Arg-Arg-Arg-sequence, which is conserved in the nucleotide-binding protamine family.

Amino Acid Sequence↗
PubMed1992

Torsade de pointes induced by hypocalcemia in a postoperative patient with thyrotoxicosis.

A 29-year-old woman with a long-term history of Graves' disease was admitted for thyroidectomy. Torsade de pointes occurred after the subtotal thyroidectomy. The level of her serum calcium was lower than normal. After administration of calcium gluconate intravenously, torsade de pointes disappeared and was no longer recorded. It is assumed that her torsade de pointes was caused by hypocalcemia as a complication of subtotal thyroidectomy.

Adult↗
PubMed1992

[Primary effect of preoperative intra-arterial infusion chemotherapy in cervical cancer].

In order to obtain better prognoses for cervical cancer, we conducted preoperative intra-arterial (i.a.) infusion chemotherapy of CDDP in combination with AT-II pressor. Two courses of i.a. chemotherapy were performed for 67 patients with cervical cancer in stage IIb containing 54 squamous cell carcinomas and 13 adenocarcinomas before operation every 3 weeks. A histologically desirable effect in cervical lesion was obtained. A group given preoperative i.a. chemotherapy had a significantly lower rate of infiltration beyond uterus in comparison with 156 patients with 145 squamous cell carcinomas and 11 adenocarcinomas treated by surgery alone as the control group. Further, the rate of histological infiltration to parametrial edges after i.a. chemotherapy tended to be lower than the control group. From the above, it was considered that preoperative i.a. infusion chemotherapy of CDDP in combination with AT-II pressor for cervical cancer was effective as a neo-adjuvant chemotherapy.

Adenocarcinoma↗
PubMed1991

Reversed effect of caffeine on non-contractile and contractile Ca2+ mobilization operated by acetylcholine receptor in mouse diaphragm muscle.

Caffeine effects on contractile and acetylcholine receptor-related non-contractile Ca2+ mobilization were investigated in phrenic nerve-diaphragm muscles of mice with neostigmine. Caffeine enhanced at 0.25-5 mM, and decreased at 7-20 mM the total amount of contractile Ca(2+)-aequorin luminescence (Ca2+ transients), but only decreased at 2-10 mM non-contractile Ca2+ transients. Pretreatment with formamide (2 M for 30 min) abolished contractile Ca2+ transients, but did not affect non-contractile ones. These results suggest that non-contractile Ca2+ mobilization is not due to direct Ca2+ release from sarcoplasmic reticulum, but due to direct modulation by nicotinic acetylcholine receptor.

Animals↗
PubMed1991

A study on the inactivation of wheat carboxypeptidase. Implication of the transient active monomer and the half-site reactivity.

The mechanism of inactivation of carboxypeptidase from wheat at high pH was studied kinetically and spectrophotometrically. Inactivation of wheat carboxypeptidase is characterized by initial, transient high activity, soon followed by loss of activity, accompanied by an increase in both fluorescence intensity and anisotropy and a decrease in circular dichroism. A scheme was proposed in which the enzyme undergoes dissociation into monomers, the total activity of which becomes twice that of the normal dimer on a mass basis, and soon further denatures and aggregates. Treatment of the enzyme with a bifunctional reagent partly prevented denaturation of the monomer and hence increased the peptide synthetic activity.

Carboxypeptidases↗
PubMed1991

Genomic structure and expression of human guanosine monophosphate reductase.

In vitro translation in the rabbit reticulocyte system and transient expression in Cos7 cells were performed to characterize the protein encoded by a chromosome 6-linked human cDNA clone, whose nucleotide sequence is homologous to that of Escherichia coli guanosine monophosphate reductase (GMP reductase) cDNA. The molecular weight of the peptide produced by the cDNA was about 37,000 Dalton, and the protein produced in the Cos7 cells exhibited GMP reductase activity, substantiating that the cDNA is for human GMP reductase. The corresponding genomic clones were obtained from two human genomic libraries. The gene spans about 50 kb and is composed of 9 exons, which encode 345 amino acid residues. Organization of exons and introns was established by DNA sequencing of each exon and splicing junctions. The gene contains two potential SpI binding sites within exon 1, and a functional atypical polyadenylation signal in exon 9.

Base Sequence↗
PubMed1991

Identification of common variant alleles of the human guanosine monophosphate reductase gene.

Examination of nucleotide sequences of genomic DNA samples obtained from several unrelated Caucasians and orientals revealed the existence of four variant alleles in the chromosome 6-linked quanosine monophosphate reductase locus. The wild-type gene has T at position 42 (counting from A of the chain initiation codon), C at 630, G at 700, and T at 766, i.e., its structure is T(42)-C(630)-G(700)-T(766). The variant gene, T-T-G-T, was found in about 10% of the loci examined. The C-to-T change at 630 was silent and did not induce any amino acid substitution (His at amino acid residue 210), but it created an additional NcoI cleavage site in the variant gene. The frequency of another variant, the T-C-G-A gene, was about 30%. The T-to-A change at 766 caused an amino acid substitution Phe----Ile at amino acid residue 256 in the variant protein. Frequencies of the C-C-G-T variant and the T-C-A-T variant were probably lower than 5% in Caucasians and orientals.

Alleles↗
PubMed1991

Ultrathin arthroscope for use in the lower compartment of the temporomandibular joint.

Arthroscopy of the temporomandibular joint has been performed mainly in the upper joint space because the instruments available have been too thick to be safely inserted into the lower joint space. This article describes a newly developed ultrathin arthroscope with an outer diameter of 0.69 mm that has been specifically developed to be used in the lower space of the temporomandibular joint. This arthroscope can be inserted into the lower joint space with a standard 18-gauge needle. The article describes the arthroscope in its initial application to patient and cadaver material.

Arthroscopes↗
PubMed1991

Maffucci's syndrome associated with intracranial enchondroma and aneurysm: case report.

Maffucci's syndrome is a rare, congenital mesodermal dysplasia combined with dyschondroplasia and hemangiomatosis. Enchondromatous involvement of the skull bones is rare in this syndrome. A rare case of Maffucci's syndrome associated with enchondroma at the skull base, left internal carotid artery aneurysm, and goiter is reported. Two other previously reported cases of Maffucci's syndrome with associated aneurysms and the present case suggest that Maffucci's syndrome may be associated with aneurysm.

Adult↗
PubMed1991

Diagnostic accuracy of temporomandibular joint lower-compartment arthroscopy using an ultrathin arthroscope: a postmortem study.

Arthroscopy was performed on the lower temporomandibular (TMJ) joint compartment of 30 fresh cadavers using a newly developed ultrathin arthroscope. Comparison of arthroscopic and dissection findings showed a diagnostic accuracy of 57%. There were both false-positive and false-negative arthroscopic diagnosis. The majority of the false diagnosis occurred in the lateral part of the joint. Iatrogenic damage to the disc occurred in one joint. The study suggests that arthroscopy of the lower joint space of the TMJ can be done with a diagnostic accuracy similar to what has been described for the upper joint space. There appears to be no major risks of iatrogenic damage to the joint structures using an ultrathin arthroscope.

Adult↗
PubMed1991

Deletion pattern in the 21-hydroxylase gene detected by polymerase chain reaction.

In order to detect deletion mutation and/or gene conversion in the 21-hydroxylase (21-OH) gene, we adopted the polymerase chain reaction (PCR) method followed by electrophoresis. Two pairs of synthesized primers, Ta/1b and 2a/2b, each corresponding to the sequence at the 5' portion of the 21-OH gene, were set for PCR. TaqI digestion of amplified DNA from normal individuals using Ta/1b as primers gave the following three fragments: an active 21-OH gene-derived 559 bp fragment, and pseudogene-derived 364 and 195 bp fragments. Of 16 patients with 21-hydroxylase deficiency (21-OHD) studied, 6 (37%) lacked the 559 bp fragment. These 6 patients also lacked both the 331 and 117 bp MvaI fragments of the PCR product which were obtained with the primers 2a/2b, both being derived from the active 21-OH gene. These results indicate that 6 of the 16 patients have either deletion of the 21-OH gene or conversion of the gene to its tandemly located pseudogene. The method described here provides a rapid diagnosis of 21-OHD.

Adrenal Hyperplasia, Congenital↗
PubMed1991

Evaluation of a filtration lymphocytapheresis (LCP) device for use in the treatment of patients with rheumatoid arthritis.

A practical on-line lymphocytapheresis (LCP) system using a leukapheresis filter (Cellsorba, Asahi Medical Co.) was evaluated in six patients with refractory rheumatoid arthritis. This filter consists of nonwoven fine polyester fiber wound around a porous cylinder. The blood was passed through the polyester fiber at a flow rate of 50 ml/min for 60 min. LCP was carried out once a week in the first month and biweekly in the next 2 months. An average of 98% of the leukocytes that entered the filter (1.27 x 10(10) cells) and 100% of the lymphocytes that entered the filter (3.66 x 10(9) cells) were removed in the first LCP. A total of 96.6% of the platelets and 2.7% of the erythrocytes that entered the filter were also removed. All of the patients showed clinical improvement in morning stiffness, Lansbury articular index, and functional capacity, with no adverse reaction. The number of circulating erythrocytes and platelets and the concentration of various serum components showed no significant change during the treatments. This LCP system required no fresh frozen plasma, albumin, or other blood transfusion. The number of circulating lymphocytes decreased to 65-70% of the pretreatment circulating lymphocyte count at the last procedure, with a decrease in the ratio of Leu3a positive cells to Leu2a positive cells. The proliferative response to phytohemagglutinin and concanavalin A was improved. These data suggest that LCP to remove approximately 3 x 10(9) lymphocytes once a week or biweekly has an immunomodulatory effect.

Arthritis, Rheumatoid↗
PubMed1991

Giant intracranial aneurysms--magnetic resonance imaging follow-up and clinical symptoms.

Twenty-four intracranial aneurysms over 20 mm in diameter were studied with magnetic resonance (MR) imaging. MR imaging follow-up of eight cases revealed induced thrombus with homogeneous intensity and decreased size even after complete intraluminal thrombosis. Most cases demonstrated homogeneous intensity thrombus in contrast to the heterogeneous intensity of spontaneous thrombus. The clinical symptoms could not be explained retrospectively by the thrombus characteristics. Perianeurysmal high intensity, indicating cerebral edema, was detected in one case presenting with a rapid increase in size. MR imaging is useful for following these pathological intra- and perianeurysmal changes.

Adult↗