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T Kondo

Publications and source records attributed to T Kondo.

At least 199 records · Page 11Linked to original sources
PubMed2001

[Basic study on the sensitivity test for inhibiting fibroblast proliferation (II)].

The results of in vitro tests against solid tumors have been generally influenced by the mixing in of fibroblasts, and so have SDI tests. We demonstrated that the influence of fibroblasts can be excluded by performing the SDI test on an agar layer, thus significantly inhibiting the growth of fibroblasts in the liquid top layer. In the agar SDI test, SDS is used to dissolve formazan; however, this lowers the sensitivity to some extent. We added additional DMSO to SDS and to raise the sensitivity.

Antineoplastic Agents↗
PubMed2000

Apoptosis induced by cadmium in human lymphoma U937 cells through Ca2+-calpain and caspase-mitochondria- dependent pathways.

Apoptosis induced by cadmium has been shown in many tissues in vivo and in cultured cells in vitro. However, its molecular mechanism is not fully understood. When the human histiocytic lymphoma cell line U937 was treated with cadmium for 12 h, evidence of apoptotic features, including change in nuclear morphology, DNA fragmentation, formation of DNA ladder in agarose gel electrophoresis, and phosphatidylserine externalization, were obtained. Moreover, loss of the mitochondrial membrane potential (Deltapsi(m)) was observed in the cadmium-treated cells and was inhibited by a broad caspase inhibitor (Z-VAD-FMK). Caspase inhibitors suppressed the DNA fragmentation in the order of Z-VAD-FMK > caspase-8 inhibitor > caspase-3 inhibitor. Expression of Bcl-x(L) and Bid decreased significantly in the cadmium-treated cells, although no apparent change in Bcl-2 and Bax expression was found. Tetrakis-(2-pyridylmethyl) ethylendiamine, a cell-permeable heavy metal chelator, partially reversed the increase of fluorescence of Fura-2 in the cadmium-treated cells. In addition, verapamil (70 microm), a voltage-dependent Ca(2+) channel blocker, inhibited the DNA fragmentation induced by cadmium less than 100 microm and decreased the fluorescence of Fura-2. Cadmium up-regulated the expression of type 1 inositol 1,4,5-trisphosphate receptor (IP(3)R) but not type 2 or type 3 IP(3)R. Calpain inhibitors I and II partially prevented DNA fragmentation. No effects of Z-VAD-FMK on the expression of type 1 IP(3)R or of calpain inhibitors on the loss of Deltapsi(m) were observed. These results suggest that cadmium possibly induced apoptosis in U937 cells through two independent pathways, the Ca(2+)-calpain-dependent pathway and the caspase-mitochondria-dependent pathway.

Amino Acid Chloromethyl Ketones↗
PubMed2000

[The respiratory system].

Explore the source record for details and available documents.

Diagnostic Techniques, Respiratory System↗
PubMed2000

Copigmentation gives bluer flowers on transgenic torenia plants with the antisense dihydroflavonol-4-reductase gene.

When anthocyanins in plants make complexes with copigments such as flavones or flavonols (copigmentation), the visible absorption maximum of the flowers is shifted so that it becomes longer: that is, the flowers look bluer. In an earlier study, our group reported the modification of flower color in torenia (Torenia fournieri Lind.) by re-introduction of the dihydroflavonol-4-reductase (DFR) gene or the chalcone synthase (CHS) gene. Our initial observation of torenia transformants was that plants with the antisense DFR gene produced bluer flowers than plants with the antisense CHS gene. In the present study we found that inactivation of the DFR gene by genetic transformation caused the accumulation of flavones - possible copigments - and that the resulting copigmentation likely to make the torenia flowers bluer. This method could be applied to other plant species to produce bluer flowers.

Journal Article↗
PubMed2000

A therapeutic approach to roentgenographically occult squamous cell carcinoma of the lung.

BACKGROUND: The significance of limited resections, including wedge resection and segmentectomy, remains controversial because of their curability rates. In the current study, the objective was to determine a strategy for the treatment of patients with roentgenographically occult bronchogenic squamous cell carcinoma (ROSCC) based on the pathologic findings from 184 patients with ROSCC who underwent resection. METHODS: In Miyagi Prefecture, 1422 patients with lung carcinoma were diagnosed during a mass screening program between 1982 and 1995. Among them, 236 patients had ROSCC, and 184 patients with ROSCC underwent pulmonary resection followed by systemic lymph node dissection. RESULTS: Pathologically, only 0.9% of the ROSCCs that were within the range of endoscopic visibility were revealed to have lymph node involvement, whereas 13% of patients with extracartilage invasion had lymph node involvement. Early ROSCC, which means ROSCC that is limited within the cartilaginous layer and is without lymph node involvement, comprised 90% of ROSCCs that measured <10 mm in longitudinal extension, comprised 77% of ROSCCs that measured 10-29 mm in longitudinal extension, and comprised 33% of ROSCCs that measured >30 mm in longitudinal extension. Eighty-nine percent of the tumors with lymph node involvement had extracartilaginous invasion. The 3-year survival rate of patients after undergoing photodynamic therapy was 100% when their tumor was regarded as early ROSCC (i.e., within 10 mm in longitudinal extension and within the range of endoscopic visibility). To date, 18 patients with ROSCC underwent segmentectomy, and all of these patients are alive without tumor recurrence. The incidence rate of multiple lung carcinomas, including synchronous and metachronous tumors, in patients with ROSCC was 22%. CONCLUSIONS: The authors concluded the following: 1) Patients with lesions that are within the range of endoscopic visibility and that measure <10 mm in longitudinal extension are candidates for photodynamic therapy. 2) Patients with lesions that are beyond the range of endoscopic visibility or that measure >10 mm in longitudinal extension are candidates for segmentectomy as long as intraoperative examination shows a tumor free bronchial stump and negative lymph nodes 11-13. 3) Patients with lesions that show bronchial obstruction or extrabronchial invasion should undergo standard resection.

Carcinoma, Squamous Cell↗
PubMed2000

Attenuation of expression of gamma-glutamylcysteine synthetase by ribozyme transfection enhance insulin secretion by pancreatic beta cell line, MIN6.

Low levels of intracellular antioxidant enzyme activities as well as glutathione (GSH) concentrations have been described in pancreatic beta cells. We examined the effects of intracellular GSH depletion on insulin secretion and the role of intracellular GSH in signal transduction in beta cell line, MIN6 cells. Anti-gamma-glutamylcysteine synthetase (gamma-GCS) heavy subunit ribozyme was stably transfected to MIN6 cells to reduce intracellular GSH concentration. In the presence of 10 mM glucose, ribozyme-transfected cells (RTC) increased insulin secretion from 0.58 microg/10(6) cells/h in control cells (CC) to 1.48 microg/10(6) cells/h. This was associated with increased intracellular Ca(2+) concentration in RTC, detected by fluo-3 staining. Our results demonstrated that intracellular GSH concentration might influence insulin secretion by MIN6 cells, and suggest that enhanced insulin secretion by beta cells conditioned by chronic depletion of GSH is mediated by increased intracellular Ca(2+) concentration.

Adenosine Triphosphate↗
PubMed2000

Treatment of Parkinson's disease in Japan.

In this paper, the course of therapy for Parkinson's disease is outlined. The rationale for the use of DA-receptor-agonist (DA agonist) monotherapy or early combination therapy using levodopa and a DA agonist is that these therapies are asociated with a lower incidence of motor complications. However, the disease progresses, the use of levodopa in combination with a DA agonist results in motor complications and development of levodopa dependency in parkinsonian patients, because the effect of levodopa on parkinsonism is very strong. In this study, a positive correlation between the Hoehn-Yahr severity score at off-periods and duration of illness was observed in parkinsonian patients with long duration of illness. This indicates that responsiveness to dopaminergic therapy still exists even in patients in advanced stages of Parkinson's disease, indicating that continuous stimulation of DA receptors and reducing the excessive fluctuation in the plasma levodopa level possibly improve motor complications. If the dose of the DA agonist is simply increased without reduction of levodopa doses, dyskinesia worsens. Although levodopa therapy is essential in the case of patients in advanced stages of Parkinson's disease, the therapeutic principle, which depends on levodopa efficacy, must be changed. Reduction of the levodopa dose and administration of a sufficient dose of a DA agonist, which is equivalent to levodopa dose reduction, is one of the possible means of effective therapy of the disease.

Journal Article↗
PubMed2000

Oligodendrocyte precursor cells reprogrammed to become multipotential CNS stem cells.

During animal development, cells become progressively more restricted in the cell types to which they can give rise. In the central nervous system (CNS), for example, multipotential stem cells produce various kinds of specified precursors that divide a limited number of times before they terminally differentiate into either neurons or glial cells. We show here that certain extracellular signals can induce oligodendrocyte precursor cells to revert to multipotential neural stem cells, which can self-renew and give rise to neurons and astrocytes, as well as to oligodendrocytes. Thus, these precursor cells have greater developmental potential than previously thought.

Animals↗
PubMed2000

Genetic variation and relationships at five STR loci in five distinct ethnic groups in China.

Five short tandem repeat (STR) systems of TH01, vWA, LPL, F13B and FES/FPS were investigated in five ethnic groups living in China (Tujia, Miao, Bai, Chaoxian and Han). All five loci did not deviate from the Hardy-Weinberg equilibrium (P>0.05). At the five loci of each ethnic group, the observed heterozygosity, the mean exclusion chance (MEC), and the power of discrimination (PD) ranged from 0.42 to 0.86, from 0.20 to 0.66 and from 0.61 to 0.95, respectively. For the five ethnic groups, the combined MEC and combined PD were >0. 9360 and >0.9998, respectively, suggesting that combinations of these five systems are feasible for DNA typing in forensic investigations such as personal identification or paternity testing. Furthermore, the allelic frequencies at the five loci suggested that these five ethnic groups were distinctly different communities. Judging from the phylogenetic tree constructed based on the genetic distance among the five ethnic groups, Han, Chaoxian and Tujia were involved in an identical cluster, and Miao and Bai in another. These findings indicate that each of the five groups examined is not only a distinct community, but also has a relationship with each of the others.

Alleles↗
PubMed2000

CikA, a bacteriophytochrome that resets the cyanobacterial circadian clock.

The circadian oscillator of the cyanobacterium Synechococcus elongatus, like those in eukaryotes, is entrained by environmental cues. Inactivation of the gene cikA (circadian input kinase) shortens the circadian period of gene expression rhythms in S. elongatus by approximately 2 hours, changes the phasing of a subset of rhythms, and nearly abolishes resetting of phase by a pulse of darkness. The CikA protein sequence reveals that it is a divergent bacteriophytochrome with characteristic histidine protein kinase motifs and a cryptic response regulator motif. CikA is likely a key component of a pathway that provides environmental input to the circadian oscillator in S. elongatus.

Alleles↗
PubMed2000

A cyclic oligophenylene containing two 1,8-naphthalene units bridged by two face-to-face biphenyl linkages exhibiting unusual strain and pi-pi interaction

1,8-[1,8-Naphthalenediylbis(4',4-biphenyldiyl)]naphthalene, a very stable strained cyclophane, has been synthesized in moderate yield using the copper-catalyzed coupling of 1, 8-bis(4-(tributylstannyl)phenyl)naphthalene. The X-ray analysis of the titled compound discloses bent p,p'-biphenylylene chains with splayed naphthalene rings, and the p,p'-biphenylylene chains located face-to-face indicate a fairly strong pi-pi interaction.

Journal Article↗
PubMed2000

Superconducting fluctuations and the pseudogap in the slightly overdoped high- T(c) superconductor TlSr2CaCu2O6.8: high magnetic field NMR studies

From measurements of the 63Cu Knight shift ( K) and the nuclear spin-lattice relaxation rate ( 1/T1) under magnetic fields from zero up to 28 T in the slightly overdoped high- T(c) superconductor TlSr2CaCu2O6.8 ( T(c) = 68 K), we find that the pseudogap behavior, i.e., the reductions of 1/T1T and K above T(c) from the values expected from the normal state at high T, is strongly field dependent and follows a scaling relation. We show that this scaling is consistent with the effects of the Cooper pair density fluctuations. The present finding contrasts sharply with the pseudogap property reported previously in the underdoped regime where no field effect was seen up to 23.2 T. The implications are discussed.

Journal Article↗
PubMed2000

Exonic deletion mutations of the Parkin gene among sporadic patients with Parkinson's disease.

Exonic deletions of the Parkin gene are common in the autosomal recessive form of juvenile parkinsonism. Here we report Parkin gene mutations among apparently sporadic Parkinson's disease (PD) patients. We screened 200 patients with PD (103 women and 97 men). The age of onset was 54.2+/-10.3years (mean+/-S.D.).Four out of the 200 patients had homozygous exonic deletions in the Parkin gene. The clinical features of these four patients were essentially the same as those of idiopathic PD. The age of onset was consistently younger (33, 38, 47 and 48years, respectively). On medication, all of them were at Hoehn and Yahr stage II or III even after 12-16years from the onset of the disease.Thus 2% of apparently sporadic PD patients in Japan have homozygous Parkin gene mutations. This positive rate was 6.3% among the patients with the age of onset below 50. Our study suggests that the prevalence of the carrier state of Parkin gene may be more than that we expected. Our study warrants further studies on Parkin gene mutations in apparently sporadic PD patients.

Journal Article↗
PubMed2000

No relationship between Taq1 a polymorphism of dopamine D(2) receptor gene and extrapyramidal adverse effects of selective dopamine D(2) antagonists, bromperidol, and nemonapride in schizophrenia: a preliminary study.

The relationship between Taq1 A polymorphism of dopamine D(2) receptor (DRD(2)) gene and extrapyramidal adverse effects of bromperidol and nemonapride, which are both antipsychotic drugs with selective and potent DRD(2) antagonistic property, was investigated in Japanese schizophrenic inpatients. Twenty-seven patients were treated with bromperidol at 6 or 12 or 18 mg/day, while 25 patients were treated with nemonapride at 18 mg/day. The duration of treatment was 3 weeks. The A1 and A2 alleles were determined by PCR. The extrapyramidal adverse effects were assessed by the Udvalg for Kliniske Unders¿ogelser side effects rating scale. Six patients were homozygous for the A1 allele, 27 were heterozygous for the A1 and A2 alleles, and 19 were homozygous for the A2 allele. There were no significant differences in the incidences or severity of extrapyramidal adverse effects between the patients with one or two A1 alleles and those with no A1 allele. The present study suggests that Taq1 A polymorphism is not related to the development of extrapyramidal adverse effects during acute phase of bromperidol and nemonapride treatments.

Acute Disease↗
PubMed2000

Purification of horse immunoglobulin isotypes based on differential elution properties of isotypes from protein A and protein G columns.

Elution properties of horse immunoglobulin isotypes from protein A and protein G columns were examined. IgGa and IgGb isotypes were bound to protein A and protein G columns and were eluted by adjusting the pH of the elution buffer from 8.0 to 2.0. IgGc bound to protein G column but not to protein A column while IgG(T) bound to both columns. IgM and IgA apparently appeared not to bind to either column. New methods for purification of serum isotypes were developed using protein A and protein G columns as well as formerly established methods. Using these methods, it was possible to obtain purified isotypes for establishment of immunological assays for practical clinical use.

Animals↗
PubMed2000

Degradation of benzyl ether bonds of lignin by ruminal microbes.

We examined microbial activity in the rumen to cleave benzyl ether bonds of lignin model compounds that fluoresced when the bonds were cleaved. 4-Methylumbelliferone veratryl ether dimer was degraded completely within 8 h even in the presence of fungicidal antibiotics, but no significant degradation occurred with bactericidal antibiotics. Degradation of a phenolic beta-O-4 trimer incorporating 4-methylumbelliferone by a benzyl ether linkage was stimulated by ruminal microbes, although its corresponding non-phenolic model compound, 1-(4-ethoxy-3-methoxyphenyl)-1-O-(4-methylumbelliferyl)-2-(2-methoxyp henoxy)-3-propanol, was not degraded. A coniferyl dehydrogenation polymer bearing fluorescent beta-O-4 benzyl ether that contains both phenolic and non-phenolic benzyl ether bonds was partially degraded (about 20%) in 48 h. These results suggest that ruminal microbes decompose benzyl ether linkages of lignin polymers under anaerobic conditions.

Anaerobiosis↗