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T Kondo

Publications and source records attributed to T Kondo.

At least 379 records · Page 21Linked to original sources
PubMed1999

New approach in the evaluation of a fitness program at a worksite.

The most common methods for the economic evaluation of a fitness program at a worksite are cost-effectiveness, cost-benefit, and cost-utility analyses. In this study, we applied a basic microeconomic theory, "neoclassical firm's problems," as the new approach for it. The optimal number of physical-exercise classes that constitute the core of the fitness program are determined using the cubic health production function. The optimal number is defined as the number that maximizes the profit of the program. The optimal number corresponding to any willingness-to-pay amount of the participants for the effectiveness of the program is presented using a graph. For example, if the willingness-to-pay is $800, the optimal number of classes is 23. Our method can be applied to the evaluation of any health care program if the health production function can be estimated.

Cost-Benefit Analysis↗
PubMed1999

Localization of precise origin of idiopathic ventricular tachycardia from the right ventricular outflow tract by a 12-lead ECG: a study of pace mapping using a multielectrode "basket" catheter.

Radiofrequency catheter ablation guided by pace-mapping techniques has proven effective in eliminating idiopathic ventricular tachycardia (VT) originating from the right ventricular outflow tract (RVOT). A method for rapidly identifying the origin of VT from 12-lead electrocardiogram (ECG) findings would be helpful for the catheter ablation procedure. The purpose of this study is to precisely localize the origin of idiopathic VT from the RVOT by a 12-lead ECG from a study of multipoint pace mapping. In one patient with premature ventricular complex (PVC) and 3 with VT, a "basket" catheter was deployed in the RVOT for bipolar pacing from 56 sites in the endocardium of RVOT. Under fluoroscopy the pacing sites were classified into the septum and free wall. We investigated the QRS morphology in leads, I, II, and III; the depth of the QS wave in leads aVR and aVL; and the height of the initial r wave in leads V1 and V2. Pacing was captured in 30-47 of 56 sites (54%-84%). As the pacing sites changed from the anterior to posterior of the septum, the QS notch (-) type in lead I shifted through rs to R, while a shift from R type to rR' or Rr' was noted in leads II and III. As the pacing sites changed from the anterior to posterior of the free wall, lead I showed a shift from the QS notch (+) type to R, while a shift from rR' to Rr' (or rR' unchanged) was found in leads II and III. The depth of the QS wave in leads aVR and aVL showed a tendency for aVR to be deeper than aVL toward the posterolateral attachment of both the septum and free wall, whereas aVL tended to be deeper than aVR toward the anterior attachment. The initial r waves in V1 and V2 became greater as the pacing site was positioned at a higher or more posterior location. These findings may provide more precise and clinically useful diagnostic information on the site of the origin of idiopathic VT originating from the RVOT by a 12-lead ECG.

Adult↗
PubMed1999

Inverse relation of body-surface activation-recovery interval and recovery time to activation time in normal subjects: stronger correlation and more heterogeneous distribution in activation-recovery interval than in recovery time.

The activation-recovery interval (ARI), measured directly from the myocardium, has shown a good correlation with the action potential duration (APD) in experiments. APD has been reported to be inversely related to the activation time (AT). However, no studies have examined the correlation between the body-surface ARI and AT in normal subjects. Fifty normal subjects (25 men and 25 women) were studied to elucidate the relationship between the body-surface ARI and AT. The body-surface AT was defined as the duration between the QRS onset and the minimum dV/dt of the QRS wave, and ARI as the interval between the minimum dV/dt of the QRS wave and the maximum dV/dt of the T wave in each lead of an 87 unipolar lead system. We also measured the recovery time (RT) defined as the duration between the QRS onset and the maximum dV/dt of the T wave. ARI was inversely correlated with AT (r = -0.73). RT was also inversely correlated with AT (r = -0.61), however, RT had a less heterogeneous distribution than ARI (148 ms vs 159 ms). There were no differences between male and female subjects in the relation between ARI and RT or in the body-surface distribution of ARI and RT. These findings suggest that the body-surface ARI may reflect recovery properties over the cardiac surface and that APD may distribute inhomogeneously over the human cardiac surface with a longer RT over an area with a shorter AT. ARI calculated from body-surface ECG may be a useful noninvasive and repeatedly measurable estimate of APD.

Adolescent↗
PubMed1999

cpmA, a gene involved in an output pathway of the cyanobacterial circadian system.

We generated random mutations in Synechococcus sp. strain PCC 7942 to look for genes of output pathways in the cyanobacterial circadian system. A derivative of transposon Tn5 was introduced into the chromosomes of reporter strains in which cyanobacterial promoters drive the Vibrio harveyi luxAB genes and produce an oscillation of bioluminescence as a function of circadian gene expression. Among low-amplitude mutants, one mutant, tnp6, had an insertion in a 780-bp open reading frame. The tnp6 mutation produced an altered circadian phasing phenotype in the expression rhythms of psbAI::luxAB, psbAII::luxAB, and kaiA::luxAB but had no or little effect on those of psbAIII::luxAB, purF::luxAB, kaiB::luxAB, rpoD2::luxAB, ndhD::luxAB, and conII::luxAB. This suggests that the interrupted gene in tnp6, named cpmA (circadian phase modifier), is part of a circadian output pathway that regulates the expression rhythms of psbAI, psbAII, and kaiA.

Amino Acid Sequence↗
PubMed1999

Role of a complex containing Rad17, Mec3, and Ddc1 in the yeast DNA damage checkpoint pathway.

Genetic analysis has suggested that RAD17, RAD24, MEC3, and DDC1 play similar roles in the DNA damage checkpoint control in budding yeast. These genes are required for DNA damage-induced Rad53 phosphorylation and considered to function upstream of RAD53 in the DNA damage checkpoint pathway. Here we identify Mec3 as a protein that associates with Rad17 in a two-hybrid screen and demonstrate that Rad17 and Mec3 interact physically in vivo. The amino terminus of Rad17 is required for its interaction with Mec3, and the protein encoded by the rad17-1 allele, containing a missense mutation at the amino terminus, is defective for its interaction with Mec3 in vivo. Ddc1 interacts physically and cosediments with both Rad17 and Mec3, indicating that these three proteins form a complex. On the other hand, Rad24 is not found to associate with Rad17, Mec3, and Ddc1. DDC1 overexpression can partially suppress the phenotypes of the rad24Delta mutation: sensitivity to DNA damage, defect in the DNA damage checkpoint and decrease in DNA damage-induced phosphorylation of Rad53. Taken together, our results suggest that Rad17, Mec3, and Ddc1 form a complex which functions downstream of Rad24 in the DNA damage checkpoint pathway.

Alleles↗
PubMed1999

Pilocarpine induces an increase in the anterior chamber angular width in eyes with narrow angles.

AIM: To determine the mechanical effects of pilocarpine on the trabecular-iris angle opening in eyes with narrow angles, compared with its effects on healthy control subjects with wide angles. METHODS: A narrow angle was defined as 25 degrees or less of trabecular-iris angle on ultrasound biomicroscopic examination. The change in anterior chamber depth (ACD), trabecular-iris angle (TIA), angle opening distance (AOD, distance between trabecular meshwork and iris) measured at 250 microm and 500 microm from the scleral spur (AOD250 and AOD500), and iris thickness was determined in 30 eyes of 30 patients (13 men and 17 women, between 63 and 82 years (mean 70.4 years)) with narrow angles and in 30 sex and age matched control subjects with wide angles before and 1 hour after the instillation of 2% pilocarpine hydrochloride by ultrasound biomicroscopy. RESULTS: In all eyes with narrow angles, pilocarpine increased the TIA, AOD250, and AOD500; these changes increased significantly and linearly as the corresponding pretreatment values decreased (r = 0.807, p = 0.0001; r = 0.787, p = 0.0001; r = 0.852, p = 0.0001). Of 30 eyes with wide angles, 23 eyes whose ACD was 2670 microm and more showed a decrease in the TIA, AOD250, and AOD500; the changes in TIA, AOD250, and AOD500 also significantly correlated with the corresponding pretreatment values (r = 0.913, p = 0.0001; r = 0.882, p = 0.0001; r = 0.895, p = 0.0001). Pilocarpine induced a smaller decrease in ACD in eyes with narrow angles than in those with wide angles (p = 0.0001). There was a linear correlation between the increase in ACD change and the decrease in pretreatment ACD in eyes with narrow angles and those with wide angles (r = 0.781, p = 0.0003; r = 0.798, p = 0.0001). CONCLUSIONS: The finding that pilocarpine increases angular width in patients with narrow angles indicates that this agent is useful for treating patients with narrow angles and angle closure glaucoma. The prediction of the pilocarpine induced change in the angle may assist ophthalmologists in treating such patients.

Aged↗
PubMed1999

Ultrasound biomicroscopic measurement of development of anterior chamber angle.

AIM: To establish normative values for the anterior segment in normal infants and children in relation to age. METHODS: Anterior segments were measured in 46 normal infants and children (21 males and 25 females, aged from 1 to 60 months (mean 17.09 (SD 16.99) months)), by use of ultrasound biomicroscopy. RESULTS: Anterior chamber depth, trabecular-iris angle, angle opening (trabecular-iris) distances at 250 and 500 microm from the scleral spur, and the thickness of the thickest part of the iris were 1724-3473 microm (2505 (SD 480) microm), 15.35-44.79 degrees (28.74 (7.46) degrees ), 116-367 microm (247.4 (65.9) microm), 166-509 microm (349.5 (87.1) microm), and 249-579 microm (434.6 (74.6) microm), respectively. All factors in this study showed a significant correlation with logarithm of age (r = 0.937, p = 0. 0001; r = 0.867, p = 0.0001; r = 0.929, p = 0.0001; r = 0.917, p = 0. 0001; r = 0.748, p = 0.0001), and significantly correlated with each other. CONCLUSIONS: Ultrasound biomicroscopy is a powerful tool for obtaining precise images and measurement of the development of the anterior segment in infants and children. Normative values were established for anterior segment dimensions in relation to age. Anterior chamber depth, trabecular-iris angle, angle opening distances at 250 and 500 microm from the scleral spur, and iris thickness showed linear increases in relation to logarithm of age.

Anterior Chamber↗
PubMed1999

Exacerbation of delayed cell injury after transient global ischemia in mutant mice with CuZn superoxide dismutase deficiency.

BACKGROUND AND PURPOSE: We have demonstrated that copper-zinc superoxide dismutase (CuZn-SOD), a cytosolic isoenzyme of SODs, has a protective role in the pathogenesis of superoxide radical-mediated brain injury. Using mice bearing a disruption of the CuZn-SOD gene (Sod1), the present study was designed to clarify the role of superoxide anion in the pathogenesis of selective vulnerability after transient global ischemia. METHODS: Sod1 knockout homozygous mutant mice (Sod1 -/-) with a complete absence of endogenous CuZn-SOD activity, heterozygous mutant mice (Sod1 +/-) with a 50% decrease in the activity, and littermate wild-type mice (male, 35 to 45 g) were subjected to global ischemia. Since the plasticity of the posterior communicating artery (PcomA) has been reported to influence the outcome of hippocampal injury, we assessed the relation between the plasticity of PcomAs and the decrease of regional cerebral blood flow in global ischemia. RESULTS: The fluorescence intensity of hydroethidine oxidation, a measurement of ethidium fluorescence for superoxide radicals, was increased in mutant mice 1 day after both 5 and 10 minutes of global ischemia, compared with wild-type mice. Hippocampal injury in the PcomA hypoplastic brains showed significant exacerbation in mutant mice compared with wild-type littermates 3 days after 5 minutes of global ischemia, although a marked difference was not observed at 1 day. CONCLUSIONS: These data suggest that superoxide radicals play an important role in the pathogenesis of delayed injury in the vulnerable hippocampal CA1 subregion after transient global ischemia.

Animals↗
PubMed1999

Transferrin synthesized in cultured human fibroblasts is associated with tubulins and has iron binding capacity.

In a previous report (13), using immunocytochemical and fluorescence-labeling techniques, we demonstrated that transferrin is synthesized in cultured human fibroblasts and that it is associated with tubulins in the cells. These morphological findings led us to attempt to elaborate those issues in more detail by biochemical methods. In this report, we were able to prove the association of transferrin produced in cells with tubulins. In addition, the transferrin associated with tubulins was found to bind to iron. These results suggest that endogenous transferrin plays a role in preventing damage caused by free radicals which can be induced by the interaction of iron with the hydrogen peroxide produced in cells.

Cells, Cultured↗
PubMed1999

Primary percutaneous transluminal coronary angioplasty performed for acute myocardial infarction in a patient with idiopathic thrombocytopenic purpura.

A 72-year-old female with idiopathic thrombocytopenic purpura (ITP) complained of severe chest pain. Electrocardiography showed ST-segment depression and negative T wave in I, aVL and V4-6. Following a diagnosis of acute myocardial infarction (AMI), urgent coronary angiography revealed 99% organic stenosis with delayed flow in the proximal segment and 50% in the middle segment of the left anterior descending artery (LAD). Subsequently, percutaneous transluminal coronary angioplasty (PTCA) for the stenosis in the proximal LAD was performed. In the coronary care unit, her blood pressure dropped. Hematomas around the puncture sites were observed and the platelet count was 28,000/mm3. After transfusion, electrocardiography revealed ST-segment elevation in I, aVL and V1-6. Urgent recatheterization disclosed total occlusion in the middle segment of the LAD. Subsequently, PTCA was performed successfully. Then, intravenous immunoglobulin increased the platelet count and the bleeding tendency disappeared. A case of AMI with ITP is rare. The present case suggests that primary PTCA can be a useful therapeutic strategy, but careful attention must be paid to hemostasis and to managing the platelet count.

Aged↗
PubMed1999

A pharmacologic study on CO2 responsiveness of intracranial pressure in rats with chronic hypercapnia.

STUDY OBJECTIVES: To investigate intracranial pressure (ICP) changes and their mechanisms in chronic hypercapnia. DESIGN: After 12 male Wistar rats were maintained in CO2-mixed air (mean PaCO2, 71.0 mm Hg) for 21 weeks, their ICP levels were measured during the breathing of 0, 5, 10, 12, and 14% CO2-mixed air before and after the i.v. administration of nitro-L-arginine methyl ester (L-NAME). The ICP responses to i.v. norepinephrine and i.v. adenosine were also tested. Ten rats that were maintained in room air served as the control group. RESULTS: The mean ICP in the study group (5.9 mm Hg) was not significantly different from the mean ICP in the control group. In the study group, the ICP response to changes in PaCO2 was significantly blunted when compared to the response seen in the control group. In both groups, i.v. norepinephrine significantly increased the ICP. In the control group but not in the study group, i.v. L-NAME suppressed the ICP response to changes in PaCO2. In both groups, i.v. adenosine significantly increased the ICP. CONCLUSIONS: The ICP response to PaCO2 was blunted in rats with chronic hypercapnia, and the mechanism of this reduced response may involve nitric oxide.

Adenosine↗
PubMed1999

Molecular forms of serum pancreatic stone protein in acute pancreatitis.

CONCLUSION: Elevation of serum pancreatic stone protein-(PSP) S1 suggests activation of trypsinogen in the pancreas. This information would prompt the start of intensive treatment and may improve prognosis of acute pancreatitis (AP). BACKGROUND: PSP exists in two molecular forms, PSP-S2-5 and PSP-S1. PSP-S1 is produced by enzyme cleavage of PSP-S2-5 by trypsin. Total serum PSP rose in AP, but little is known about its molecular forms. In this study, we characterized the molecular forms of serum PSP in AP. METHODS: Sera were taken from 8 patients with severe acute pancreatitis (sAP) and from 11 patients with mild acute pancreatitis (mAP). Serum PSP was characterized by high-performance liquid chromatography (HPLC) followed by the specific enzyme immunoassay (EIA). RESULTS: The total serum PSP in sAP was higher than in mAP, but the difference was not significant. The PSP-S1 was detected in serum in all (7/7) patients in sAP and in 72% (8/11) of patients in mAP. Serum level of PSP-S1 was significantly higher in sAP than that in mAP (p < 0.05), and the cutoff value to distinguish the two groups was 30 ng/mL. Serum PSP-S1 did not show significant correlation with total PSP, immunoreactive trypsin, or C-reactive protein.

Acute Disease↗
PubMed1999

A prospective multicenter trial evaluating diagnostic validity of multivariate analysis and individual serum marker in differential diagnosis of pancreatic cancer from benign pancreatic diseases.

CONCLUSION: A multivariate analysis of CAMPAS-PX2 can increase its diagnostic accuracy in differential diagnosis of pancreatic cancer from benign pancreatic or extrapancreatic disease, when compared with CA19-9 alone. However, the improvement in diagnostic accuracy is still not satisfactory in spite of an elaborate combination of serum markers in diagnosis for pancreatic cancer. Optimal combination of a sensitive serum marker and another diagnostic modality, such as ultrasonography, can be a practical way to improve important diagnostic and cost-effectiveness in diagnosis for pancreatic cancer. BACKGROUND: No specific biological test has yet been developed for diagnosis of pancreatic cancer, although increasing numbers of tumor markers become available. For improvement in the diagnostic and cost effectiveness, it is important to select optimal combination of several serum markers relatively independent of each other. METHODS: A new model of discriminant function, computer-aided multivariate and pattern analysis system for pancreatic cancer examination 2 (CAMPAS-PX2), was developed based on the data of the 23 serum tumor markers from the first prospective trial (1) to differentiate between pancreatic cancer and benign pancreatobiliary disease by logistic regression analysis using a stepwise selection method. In 243 patients suspected of having pancreatic pancreatic cancer by a multicenter prospective study, the diagnostic value of the multivariate analysis, CAMPAS-PX2, was compared with the 23 markers. RESULTS: Pancreatic cancer was subsequently identified in 27 patients. Positive in disease, negative in health, and area under receiver operating characteristic curve were significantly higher by CAMPAS-PX2 (89, 87, 91%) than by CA 19-9 (78, 82, 84%), the most sensitive marker among the 23 markers.

Biomarkers, Tumor↗
PubMed1999

Alpha-adrenergic blockade in preventing posttransplant edema of lung allograft.

Effect of alpha-adrenergic blockers on pulmonary edema in lung transplantation was studied with a rat model of syngeneic left lung transplantation. Prior to harvesting, 0.1 mg of Prazosin or 0.4 mg of Yohimbine was given to the donor. Pulmonary and systemic hemodynamics were measured under the right pulmonary arterial occlusion (RPAO) at different time points after grafting. Wet to dry weight ratio (W/D) of all transplants was also calculated. Same procedure was conducted in rats with normal and ischemic lung and in transplanted animals without any treatments. While RPAO did not increase W/D in normal lung with a significant elevation in pulmonary arterial pressure (PAP), both these values significantly increased in transplanted lung. Transplanted animals could not tolerate RPAO 24 hours after grafting, but were tolerable later than 48 hours with elevated W/D and PAP. On the contrary, animals given Prazosin or Yohimbine were all tolerable at 24 hours postsurgery. Yohimbine significantly improved W/D. Consequently, it was demonstrated that pulmonary edema of the graft reached its peak during first 24 to 48 hours after transplantation and was alleviated by the blockade of alpha-adrenergic receptor in the graft vessel.

Adrenergic alpha-Antagonists↗
PubMed1999

Stimulated neutrophils evoke signal transduction to increase vascular permeability in rat lungs.

The mechanisms by which stimulated neutrophils (PMNs) damage pulmonary vascular endothelium were investigated using twenty-four perfused lung preparations isolated from rats. We tested the ability of unstimulated and mechanically stimulated PMNs to adhere to pulmonary endothelial cells and, thereby, alter pulmonary vascular permeability (measured as the pulmonary filtration coefficient) and hemodynamics. To stimulate PMNs, they were gently agitated in a glass vial for 10 seconds. Perfusing lungs with the stimulated PMNs (stimulated group) elicited a 3-fold increase in the filtration coefficient as compared to lungs perfused with unstimulated cells (unstimulated group). This increase in filtration was completely blocked by preincubation of stimulated PMNs with CD18 monoclonal antibody (MoAb group). This increase in filtration coefficient was also completely blocked by GF109203X, a protein kinase C inhibitor (GF group). Pulmonary vascular resistance increased when the stimulated PMNs were injected to the isolated lungs. Although, preincubation of stimulated PMNs with CD18 MoAb successfully blocked and GF109203X partly blocked this increase in pulmonary vascular resistance. The accumulation of stimulated PMNs within the lungs, as assessed by myeloperoxidase (MPO) levels, was blocked by preincubation of stimulated PMNs with CD18 MoAb. However, GF109203X did not decrease MPO levels. These findings suggest that stimulated PMN-induced increases in pulmonary vascular filtration, resulted from endothelial cell injury caused by adhesion to the endothelial cells, evoke intracellular signaling within the endothelial cells.

Animals↗
PubMed1999

Pseudogout attack associated with chronic thyroiditis and Sjögren's syndrome.

A 66-year-old woman, diagnosed with chronic thyroiditis at age 63, presented with anorexia and fatigue. Therapy for the chronic thyroiditis consisted of levothyroxine sodium (100 microg/day). Her symptoms were attributed to the insufficient supply of levothyroxine sodium. Following a dosage increase to 150 microg/day, she suffered from an acute attack of pseudogout. Clinical features were complicated by Sjögren's syndrome, which appeared after treatment onset. Pseudogout was effectively treated by colchicine after administration of diclofenac sodium failed to alleviate the symptoms. Pseudogout is a recognized complication of thyroid replacement therapy, but association with Sjögren's syndrome has not been previously reported.

Aged↗