Biomedical subjects

T Kondo

Publications and source records attributed to T Kondo.

At least 127 records · Page 7Linked to original sources

PubMed2001

Association between TaqI A dopamine D2 receptor polymorphism and therapeutic response to bromperidol: a preliminary report.

The relationship between TaqI A dopamine D2 receptor (DRD2) polymorphism and therapeutic response to bromperidol, a selective dopamine antagonist, was investigated in 30 acutely exacerbated schizophrenic inpatients. Patients were treated with bromperidol 6-18 mg/day for 3 weeks. Clinical symptoms were evaluated by the Brief Psychiatric Rating Scale (BPRS) before and 3 weeks after the treatment. The TaqI A genotypes were determined with the PCR method. There was no significant difference in the percentage improvement of total BPRS or 5-subgrouped symptoms (positive, negative, anxiety-depression, excitement and cognitive symptoms) after the 3-week treatment between the patients with A1 alleles (n=18) and those with no A1 allele (n=12). Although the present study is preliminary, it is suggested that the TaqI A DRD2 polymorphism is not associated with therapeutic response to bromperidol in schizophrenic patients.

Adult↗

PubMed2001

Cloning of DNA sequences localized on proximal fluorescent chromosome bands by microdissection in Pinus densiflora Sieb. & Zucc.

Japanese red pine, Pinus densiflora, has 2n=24 chromosomes, of which most carry chromomycin A3 (CMA) and 4',6-diamidino-2-phenylindole (DAPI) bands at their centromere-proximal regions. It was proposed that these regions contain highly repetitive DNA. The DNA localized in the proximal fluorescent bands was isolated and characterized. In P. densiflora, centromeric and neighboring segments of the somatic chromosomes were dissected with a manual micromanipulator. The centromeric DNA was amplified from the DNA contained in dissected centromeric segments by degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR) and a cloned DNA library was constructed. Thirty-one clones carrying highly repetitive DNA were selected by colony hybridization using Cot-1 DNA from this species as a probe, and their chromosomal localization was determined by fluorescent in situ hybridization (FISH). Clone PDCD501 was localized to the proximal CMA band of 20 chromosomes. This clone contained tandem repeats, comprising a 27 bp repeat unit, which was sufficient to provide the proximal FISH signal, with a 52.3% GC content. The repetitive sequence was named PCSR (proximal CMA band-specific repeat). Clone PDCD159 was 1700 bp in length, with a 61.7% AT content, and produced FISH signals at the proximal DAPI band of the remaining four chromosomes. Four clones hybridized strongly to the secondary constriction and gave weak signals at the centromeric region of several chromosomes. Clone PDCD537, one of the four clones, was homologous to the 26S rRNA gene. A PCR experiment using microdissected centromeric regions suggested that the centromeric region contains 18S and 26S rDNA. Another 24 clones hybridized to whole chromosome arms, with varying intensities and might represent dispersed repetitive DNA.

Base Sequence↗

PubMed2001

Complete transection of the pancreas due to a single stamping injury: a case report.

Complete transection of the pancreas due to a single stamping injury is reported. A 47-year-old female was stamped on in the epigastric region by her common-law husband when lying on her back. Immediately after the stamping, she complained of severe abdominal pain. In an emergency hospital, the abdominal CT (computed tomography) scan showed a large haematoma around the pancreas head. In the surgical operation that followed, a complete transection of the pancreas between the head and body was unexpectedly discovered. Furthermore, severe traumatic changes were found in the liver, mesentery, splenic artery and vein. The medico-legal autopsy revealed marked haemorrhaging in the abdominal subcutaneous adipose tissue and rectus muscle in the epigastric region. The external blunt force that acted on the abdomen had forcibly compressed the pancreas against the spinal column. Blunt pancreatic injury is relatively uncommon, but pancreatic injuries should always be considered in patients or autopsy cases after external blunt force to the abdomen.

Autopsy↗

PubMed2001

The 3'-terminal sequence of chinese yam necrotic mosaic virus genomic RNA: a close relationship with macluravirus.

The nucleotide sequence of the 3'-terminal 1,905 residues of the Chinese yam necrotic mosaic virus (ChYNMV) RNA genome was determined. It contains one long open reading frame, which consists of 1,671 nucleotides encoding a protein of 557 amino acid residues. A partial amino acid sequence of the coat protein determined from purified ChYNMV particles was identical to the portion of the amino acid sequence deduced from the determined nucleotide sequence, which suggests that the nucleotide sequence includes the coat protein gene. Surprisingly, a homology search using the deduced amino acids sequence of the coat protein revealed that ChYNMV is closely related to the genus Macluravirus within the family Potyviridae, although the virus has long been considered to be a carlavirus. Identification of cylindrical cytoplasmic inclusions, which are characteristic of the family Potyviridae, in ChYNMV-infected Chinese yam cells, as well as the morphology and length (660 nm) of the purified virus particles, support including the virus as a tentative new member of the genus Macluravirus.

Amino Acid Sequence↗

PubMed2001

Segmentectomy for roentgenographically occult bronchogenic squamous cell carcinoma.

BACKGROUND: Roentgenographically occult bronchogenic squamous cell carcinomas (ROSCCs) are early squamous cell lung cancers of central type. Some of them cannot be treated with intrabronchial therapy. Although surgical treatment was performed for such tumors, it was unknown whether lobectomy was indispensable or not. METHODS: The clinicopathologic information of the 58 patients who underwent segmentectomy for ROSCCs were collected from 16 hospitals and reviewed retrospectively, compared with 98 patients who underwent lobectomy for ROSCCs. RESULTS: Five-year survival rate of the 58 patients based on lung cancer deaths was 96.8%, and 82.6% including all causes of death. The duration of chest tube drainage in the segmentectomy group was slightly longer than in the lobectomy group. Operative mortality and the frequency of postoperative complications were not statistically different in both groups. Postoperative/preoperative vital capacity and forced expiratory volume in 1 second were higher in the segmentectomy group. CONCLUSIONS: These results suggest that segmentectomy may be an alternative for surgical therapy of carefully selected ROSCCs. More prospective studies are required to fully demonstrate clinical benefit.

Adult↗

PubMed2001

Curvature elasticity of multilamellar lipid bilayers close to the chain-melting transition.

We directly measured curvature elasticity of dipalmitoylphosphatidylcholine multilamellar bilayers close to the chain-melting transition using the method of electric-field-induced bending deformation of the cylindrical tubes. The result shows that the bending modulus, kappa(c), decreases remarkably at temperatures close to the melting transition temperature. This reflects a softening of the bilayer resulted from the area fluctuations as predicted theoretically. However, the decrease of kappa(c) near the transition is far smaller than that predicted. This is due to the experimental method and the narrow transition width of the multilamellar bilayers. Nevertheless, the result obtained gives direct evidence of the kappa(c) reduction predicted for multilamellar membranes in the transition regime. Below about 41 degrees C, almost of all cylindrical tubes cannot response to the electric field, indicating a very large bending rigidity.

1,2-Dipalmitoylphosphatidylcholine↗

PubMed2001

Risk stratification using serum concentrations of cardiac troponin T in patients with end-stage renal disease on chronic maintenance dialysis.

BACKGROUND: It has been recently suggested that cardiac troponin T (cTnT) may be more sensitive than troponin I (cTnI) for subclinical myocardial cell injury in patients on chronic dialysis. METHODS: We prospectively compared the predictive value of cTnT with cTnI, atrial (ANP) and brain natriuretic peptide (BNP) in 100 consecutive outpatients on chronic dialysis without acute coronary syndromes over a period of 3 months, and assessed whether the combination of cTnT with clinical information including age, duration of dialysis, and medical histories was useful for risk stratification of these patients. During the 2-year follow-up period, 19 patients died, mostly due to cardiac causes (53%). RESULTS: The area under the receiver operator characteristic (ROC) curve for the cTnT as predictor of both overall and cardiac death was significantly greater than the area under the cTnI curve (p < 0.0001 and p = 0.01), the BNP curve (p < 0.001 and p < 0.01) or the ANP curve (p < 0.0001 and p < 0.005). In a stepwise multivariate Cox regression analysis, only cTnT (p < 0.05 and p < 0.01) and a history of heart failure requiring hospitalization (p < 0.05 and p < 0.005) were independent predictors of both all cause and cardiac mortality. Using parameters of cTnT > or =0.1 microg/l and/or history of heart failure, the overall and cardiac mortality rate for the low risk group (n=66) were 4.5% and 1.5%, respectively, 40% and 16% for the intermediate risk group (n=25), and 67% and 56% for the high risk group (n=9). CONCLUSION: cTnT concentrations offer a higher prognostic accuracy than cTnI, ANP and BNP in patients on chronic dialysis. The combination of elevated cTnT and a history of heart failure may be a highly effective means of risk stratification of these patients.

Adult↗

PubMed2001

Diagnostic results before and after introduction of autofluorescence bronchoscopy in patients suspected of having lung cancer detected by sputum cytology in lung cancer mass screening.

For the purpose of early detection, we have conducted population-based mass screening for lung cancer by sputum cytology since 1982. Although detection of lung cancer in its early stage is important for a good prognosis, it is often difficult to localize lesions in roentgenographically occult cancer. To clarify the role of autofluorescence bronchoscopy in localizing tumors in patients with roentgenographically occult cancer, we analyzed our diagnostic results. Fifty patients who had been detected by sputum cytology were screened by the light-induced fluorescence endoscope (LIFE)-Lung System from November 1997 to April 1999. We compared the results according to the screening methods: conventional bronchoscopy alone versus LIFE with conventional white-light bronchoscopy (November 1997 to April 1999). Twenty-eight cancerous lesions and 39 borderline lesions were detected by LIFE. Of the 39 borderline lesions, nine were detected only by LIFE. Multicentric lesions including cancer or dysplasia were also detected in 21 of the 50 patients by LIFE. The sensitivity by white-light bronchoscopy alone was 85.3%, whereas that of the LIFE-Lung System with white-light bronchoscopy was 94.1% (P=0.078). There were no cancerous lesions in the area observed as normal by LIFE. We also compared the diagnostic results of two localization methods: brushing of all bronchi (September 1986 to December 1990) and the LIFE-Lung System (November 1997 to April 1999). Although this was a historical comparison, the number of detected borderline lesions increased, which led to a high detection rate in patients with suspected-positive sputum (P=0.0006) by the LIFE-Lung System. In conclusion, the LIFE-Lung System is a safe and non-invasive system for detecting small intraepithelial lesions of the tracheobronchial tree. Autofluorescence bronchoscopy is more efficacious for localizing intraepithelial lesions and places fewer burdens on the patient than brushing of all bronchi.

Bronchoscopy↗

PubMed2001

Two-dimensional gel electrophoretic studies on the cellular aging: accumulation of alpha-2-macroglobulin in human fibroblasts with aging.

To understand the mechanisms that control life span and age-related phenotypes, we used two-dimensional (2D) gel electrophoresis to study the intracellular proteins whose amounts change during the process of cellular aging. We found that the amount of an alpha-2-macroglobulin (A2M) fragment derived from culture medium increased in the cells with aging. A2M is linked to Alzheimer's disease both genetically and functionally. This is the first report of accumulation of an A2M fragment in senescent fibroblasts. We also studied 2D gel profiles of human fibroblasts immortalized by treatment with either 60Co gamma rays or 4-nitroquinoline 1-oxide. As immortalized cells overcome cellular senescence to gain an unlimited life span, the proteins whose amounts change after immortalization may be relevant to the age-related phenotypes. 2D gel analysis revealed that the A2M fragment was down-regulated in the immortalized cells, compared with their normal counterparts, regardless of their passage. We also found that the other four proteins increased in amount with aging and decreased in amount after immortalization. Our results suggest: (1) the A2M incorporation into the cells is increased in the process of cellular aging; and (2) A2M may be linked to the age-related phenotypes that were lost during the process of immortalization of human cells.

Cell Line↗

PubMed2001

Up-regulation of S100C in normal human fibroblasts in the process of aging in vitro.

S100 proteins belonging to the EF-hand Ca(2+)-binding protein family regulate a variety of cellular processes via interaction with different target proteins. Several diseases, including cancer and Alzheimer's disease, are related to a disorder of multifunctional S100 proteins, which are expressed in cell- and tissue-specific manners. We previously demonstrated that S100C could move to and accumulate in the nuclei of normal human fibroblasts but not in the nuclei of immortalized and neoplastic cells. In addition, we found that its nuclear accumulation resulted in suppression of DNA synthesis in normal cells at a confluent stage. In the present study, we investigated whether S100C was associated with cellular senescence in vitro. We found that S100C expression increased in normal human fibroblasts in the process of aging in culture and was accompanied by accumulation of its protein in the nuclei of senescent fibroblasts. In addition, the nuclear accumulation of S100C increased expression of a cyclin-dependent kinase inhibitor p21(Sdi1), a strong inhibitor of cell growth. These findings suggest that an increase in the cells having nuclear accumulation of S100C is closely related to the process of cellular senescence of normal human fibroblasts.

Cell Division↗

PubMed2001

A convenient method for discriminating between natural and depleted uranium by gamma-ray spectrometry.

A convenient method for discriminating between natural and depleted uranium reagent was developed by measuring and analyzing the gamma-ray spectra of some reagents with no standard source. The counting rates (R) of photoelectric peaks of gamma-rays from nuclides with the same radioactivity divided by their emission probability (B) are expressed as a function of gamma-ray energy. The radioactivities of 234Th and 234mPa and 21.72 times that of 235U are equal to the radioactivity of 235U in natural uranium. Therefore, the plot of 21.72-fold R/B for 235U should be on a curve fitted to the points for 234Th and 234mPa in natural uranium. Depleted uranium with a 235U isotopic composition of less than 0.68% could be discriminated from natural uranium in the case of a reagent containing 4.0 g of uranium.

Algorithms↗

PubMed2001

Rapid analysis of pesticide components, xylene, o-dichlorbenzene, cresol and dichlorvos, in blood and urine by pulse heating-gas chromatography-mass spectrometry.

Analysis of the pesticide components, xylene, o-dichlorbenzene (DCB), cresol and dichlorvos (DDVP, an organophosphate), was attempted using 3 microl of biological samples by pulse heating (Py)-gas chromatography-mass spectrometry (GC-MS) without pretreatment. Xylene, DCB, cresol and DDVP were separately detected by Py-GC-MS. The regression lines for these four substances in the blood were shown to be linear between the peak height and their concentrations, 0.1/0.2-20 microg/ml. Recoveries of DDVP, cresol, DCB and xylene at the concentration of 1.0 microg/ml by Py-GC-MS ranged from 78.8 to 89.0% in blood, and from 84.2 to 91.2% in urine. For within-run precision, the coefficient of variation values at the concentration of 1.0 microg/ml ranged from 7.9 to 10.6% in blood, and from 5.8 to 9.4% in urine. The lower detection limits of xylene, DCB, cresol and DDVP in blood were 50, 50, 50 and 150 ng/ml, respectively. In comparison with the measured value in blood that was added to these four substances, Py-GC-MS showed good accuracy similar to GC-MS after the extraction method. DDVP and xylene could be successfully determined by Py-GC-MS in blood and urine in emergency medical and autopsy cases. From these results, Py-GC-MS can be performed in a short analytical time (15 min) and is a useful method to determine pesticide components in forensic medicine and emergency medical practice.

Journal Article↗

PubMed2001

"Nematic ordered cellulose": a concept of glucan chain association.

Native cellulose consists of a set of parallel chains composed of glucose. Most of the time, these chains are highly ordered and form a structure that is known as a microfibril. On the other hand, highly crystalline forms of cellulose are more difficult to process and often are unpredictable in their behavior. If an ordered but noncrystalline form of cellulose could be produced, this would greatly extend the possibilities of usage of cellulose to new areas. In this paper, we have produced such a new supermolecular structure of cellulose, called nematic ordered cellulose. The unique characteristics of this supermolecular structure of cellulose have been clarified using various kinds of physicochemical analyses. Using a high-resolution transmission electron microscopic approach, we have also imaged the single glucan chains, demonstrating the close but nonprecise association usually found in crystalline biopolymers.

Carbohydrate Conformation↗

PubMed2001

Inhibition of in vitro metabolism of simvastatin by itraconazole in humans and prediction of in vivo drug-drug interactions.

PURPOSE: To evaluate an interaction between simvastatin and itraconazole in in vitro studies and to attempt a quantitative prediction of in vivo interaction in humans. METHODS: The inhibitory effect of itraconazole on simvastatin metabolism was evaluated using human liver microsomes and the Ki values were calculated for the unbound drug in the reaction mixture. A physiologically-based pharmacokinetic model was used to predict the maximum in vivo drug-drug interaction. RESULTS: Itraconazole competitively inhibited the metabolism of simvastatin to M-1 and M-2 with Ki values in the nM range. The area under the curve (AUC) of simvastatin after concomitant dosing with itraconazole was predicted to increase ca. 84-101-fold compared with that without administration of itraconazole. Taking into consideration the fact that this method predicts the maximum interaction, this agrees well with the clinical observation of a 19-fold increase. A similar prediction, based on the Ki value without taking into account the drug adsorption to microsomes, led to an underevaluation of the interaction. CONCLUSIONS: It was demonstrated that the competitive inhibition of CYP3A4-mediated simvastatin metabolism by itraconazole is the main cause of the drug interaction and that a Ki value corrected for drug adsorption to microsomes is the key factor in quantitatively predicting the maximum in vivo drug interactions.

Anticholesteremic Agents↗

PubMed2001

Expression of nucleolar protein p120 predicts poor prognosis in patients with stage I lung adenocarcinoma.

BACKGROUND: P120 is a proliferation-associated nucleolar protein found in most human malignant tumors, but not in resting normal cells. In our previous studies, the expression of p120 was statistically correlated with the proliferation capacity in human lung cancer cells and could be a prognostic marker for resected lung adenocarcinoma. PATIENTS AND METHODS: The expression levels of p120 in tumors were assessed by immunohistochemistry in 59 patients with stage I lung adenocarcinoma who underwent radical resection. Using clinical follow-up data, the prognostic significance of p120 calculated by labeling indices was evaluated using Cox's proportional hazard model. RESULTS: A mean +/- SD of the labeling index of p120 was 35.3+/-14.4%. No significant correlation was found between the expression levels of p120 and clinicopathological factors. Using a cutoff value of 35% in the labeling index of p120, patients with high expression of p120 experienced early recurrence and shorter survival compared with those having low expression of p120 (P = 0.04). Multivariate analysis revealed that p120 served as an independent and strongest prognostic factor for resected lung adenocarcinoma (P = 0.033). CONCLUSION: This article provides the first evidence that the expression levels of p120 in tumor tissues can be used as an independent and powerful prognostic marker for resected stage I lung adenocarcinoma.

Adenocarcinoma↗

PubMed2001

MCT1-mediated transport of L-lactic acid at the inner blood-retinal barrier: a possible route for delivery of monocarboxylic acid drugs to the retina.

PURPOSE: The aim of this study was to characterize L-lactic acid transport using a conditionally immortalized rat retinal capillary endothelial cell line (TR-iBRB2) as a model of in vitro inner blood-retinal barrier (iBRB) to obtain a better understanding of the transport mechanism at the iBRB. METHODS: TR-iBRB2 cells were cultured at 33 degrees C, and L-lactic acid uptake was monitored by measuring [14C]L-lactic acid at 37 degrees C. The expression and mRNA level of monocarboxylate transporter (MCT)1 and MCT2 were determined by reverse transcription polymerase chain reaction (RT-PCR) and quantitative real-time RT-PCR with specific primers, respectively. RESULTS: The [14C]L-lactic acid uptake by TR-iBRB2 cells increased up to a pH of 5.0 and was inhibited in the presence of 10 mM L-lactic acid. The [14C]L-lactic acid uptake at pH 6.0 was both temperature- and concentration-dependent with a Michaelis-Menten constant of 1.7 mM and a maximum uptake rate of 15 nmol/(30 s mg of protein). This process was reduced by carbonylcyanide p-trifluoromethoxyphenylhydrazone (protonophore), alpha-cyano-4-hydroxycinnamate, and p-chloromercuribenzenesulfonate (typical inhibitors for H+-coupled monocarboxylic acid transport), suggesting that L-lactic acid uptake by TR-iBRB2 cells is a carrier-mediated transport process coupled with an H+ gradient. [14C]L-Lactic acid uptake was markedly inhibited by monocarboxylic acids but not dicarboxylic acids and amino acids. Moreover, salicylic and valproic acids competitively inhibited this process with an inhibition constant of 4.7 mM and 5.4 mM, respectively. Although MCT1 and MCT2 mRNA were found to be expressed in TR-iBRB2 cells, MCT1 mRNA was found to be present at a concentration 33-fold greater than that of MCT2 mRNA using quantitative real-time PCR. [14C]L-Lactic acid was significantly reduced by 5-(N,N-hexamethylene)-amiloride at pH 7.4 and Na+/H+ exchanger I mRNA was expressed in TR-iBRB2 cells. CONCLUSION: L-Lactic acid transport at the iBRB is an H-coupled and carrier-mediated mechanism via MCT1 that is competitively inhibited by monocarboxylate drugs.

Animals↗

PubMed2001

Effects of genetic polymorphism of CYP1A2 inducibility on the steady-state plasma concentrations of trazodone and its active metabolite m-chlorophenylpiperazine in depressed Japanese patients.

The effects of a genetic polymorphism of inducibility of cytochrome P450 (CYP) 1A2 on the steady-state plasma concentrations of trazodone and its active metabolite, m-chlorophenylpiperazine, were studied in order to clarify if these steady-state plasma concentrations are dependent on the CYP1A2 polymorphism. Fifty-eight Japanese depressed patients received trazodone 150 mg/day at bedtime. The steady-state plasma concentrations of trazodone and m-chlorophenylpiperazine were measured in duplicate using high performance liquid chromatographic method, and were corrected to the mean body weight for analyses. A point mutation from guanine (wild type) to adenine (mutated type) at position -2964 in the 5'-flanking region of CYP1A2 gene was identified by polymerase chain reaction fragment length polymorphism method. The mean steady-state plasma concentration of trazodone, but not m-chlorophenylpiperazine was significantly (P<0.05) lower in smokers than in non-smokers. Twenty-two smokers had 16 homozygotes of the wild type allele, 5 heterozygotes of the wild type and mutated alleles, and one homozygote of the mutated allele. There was no significant difference in the mean steady-state plasma concentration of trazodone or m-chlorophenylpiperazine between smokers with no mutation and those with mutation, although one homozygote of the mutated allele had the highest steady-state plasma concentration of trazodone in smokers. The present study thus suggests that CYP1A2 polymorphism does not necessarily have predictive value of the steady-state plasma concentration of trazodone or m-chlorophenylpiperazine in most of the smokers treated with trazodone.

Adult↗

PubMed2001

Dendritic cells signal T cells in the absence of exogenous antigen.

Interactions with self-major histocompatibility complex molecules on dendritic cells (DCs) are important for the survival of mature CD4+ T cells. We have followed the DC-mediated signal from the T cell surface to the nucleus and identified a pattern of activation that correlates with increased in vitro survival. This response is induced exclusively by DCs and is likely associated with a modulation of the T cell activation threshold. We have also found that DC-mediated activation results in antigen-independent cytokine gene expression, which points to a new role for DCs in shaping the cytokine milieu. Such antigen-independent activation of T cells may play a role in protective immunity, but may also induce and perpetuate autoimmune states such as multiple sclerosis.

Antigens↗