Biomedical subjects

Y Kondoh

Publications and source records attributed to Y Kondoh.

At least 19 recordsLinked to original sources

PubMed1995

Regional myocardial function curve of the ventricle.

To understand the pathophysiology of diseased hearts, we devised a new regional myocardial function curve and investigated its properties. Regional work per unit volume of the myocardium (RWM) was calculated by integrating mean wall stress (sigma) with respect to the natural logarithm of the reciprocal of wall thickness [ln(1/H)] over a cardiac cycle. Regarding the end-diastolic ln(1/H) as the preload for the region of concern on the assumption that the myocardium is incompressible, we defined the relation between RWM and end-diastolic ln(1/H) as the regional myocardial function curve. In ten mongrel dogs, we measured left ventricular pressure, left ventricular internal diameter, and wall thickness with a catheter-tip micromanometer and ultrasonic dimension gauges during volume loading to obtain the regional myocardial function curve. We examined the sensitivity of the regional myocardial function curve to changes in contractile state (isoproterenol, propranolol) and changes in afterload (pressure loading by a balloon-occlusion catheter). The linear fit to the data points of the regional myocardial function curve under each condition always achieved a very good correlation coefficient (greater than 0.62). Isoproterenol increased the slope of the regional myocardial function curve from 9.7 +/- 0.9 (SEM) mJ/cm3 to 14.4 +/- 1.0 mJ/cm3 (P < 0.01), with no significant changes in the x-intercept, while propranolol decreased it to 5.6 +/- 1.2 mJ/cm3 (P < 0.01) with no significant changes in the x-intercept.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1995

Dynamics of neurons controlling movements of a locust hind leg: Wiener kernel analysis of the responses of proprioceptive afferents.

1. The response properties of proprioceptive sensory neurons providing input to the local circuits controlling leg movements of the locust have been analysed by the Wiener kernel method. The proprioceptor, the femoral chordotonal organ, encodes the position and movements of the tibia about the femorotibial joint. 2. Intracellular recordings were made from sensory neurons while the apodeme of the organ was moved with a band-limited Gaussian white noise signal with a cutoff frequency of 27, 58, or 117 Hz. To define the input-output characteristics of the neurons, the first- and second-order Wiener kernels were computed by a cross-correlation between the spike response of the afferents and the white noise stimulus. 3. White noise stimulation elicited sustained spiking in 50 out of 54 afferents throughout the 20 s periods of stimulation and recording. The first-order kernels, the linear response properties, of these afferents were of six basic types that were dependent on the cutoff frequency of the white noise stimulus. These included 1) flexion-sensitive afferents that were primarily position sensitive irrespective of stimulus frequency, 2) flexion-sensitive afferents that were position sensitive at low frequencies but also coded velocity at higher frequencies, 3) flexion-sensitive afferents that coded velocity at all stimulus frequencies, 4) flexion-sensitive afferents that coded velocity at low stimulus frequencies but also acceleration at high frequencies, 5) extension-sensitive afferents that coded velocity at all stimulus frequencies, and 6) extension-sensitive afferents that coded velocity at low stimulus frequencies and acceleration at high frequencies. A seventh type contained the four remaining afferents that adapted rapidly to the stimulus within 3-5 s. These were all extension-acceleration sensitive irrespective of stimulus frequency. 4. The gain curves (produced by Fourier transform of the 1st-order kernels) and the power spectra of the linear models (produced by convolving the 1st-order kernels with the white noise) demonstrated that responses in the position-sensitive afferents are representative of a constant gain low-pass filter with a cutoff frequency of approximately 80 Hz, whereas those in the velocity- and acceleration-sensitive afferents are band passed, having peaks at 80 Hz. 5. The main nonlinearity was a signal compression in which the diagonal peak(s) of the second-order nonlinear kernels offset one or more peaks of the first-order kernels and represents a rectification or directional sensitivity of the afferents.(ABSTRACT TRUNCATED AT 400 WORDS)

Afferent Pathways↗

PubMed1995

Simultaneous visualization of Q-bands and FISH signals using a novel fluorochrome.

We developed a new HNPP-azo dye method for detection of fluorescence in situ hybridization (FISH) signals on Q-banded chromosomes by use of a newly synthesized fluorochrome, HNPP (3-hydroxy-N-2'-biphenyl-2-naphthalenecarboxamide phosphate ester), which reacts enzymatically with alkaline phosphatase and azo dye. The FISH staining method permits simultaneous detection of orange HNPP signals on chromosomal sites labeled by Q-banding, allowing the assignment of small (440-1,200 bp) probes.

Animals↗

PubMed1995

Deletion of the Wilson's disease gene in hereditary hepatitis LEC rats.

LEC rats develop disorder of cooper metabolism and hepatitis similar to those of human Wilson's disease. We recently demonstrated that the gene responsible for hepatitis (hts) of LEC rats is homologous to Wilson's disease gene (WD). The present study showed a deletion of at least 90 base pair of WD cDNA in LEC rats, which corresponds to nucleotides 3981 to 4071 in human WD cDNA sequence. This deletion was linked with hepatic copper accumulation and hepatitis, and considered to be a primary mutation for hepatic disorder in the LEC rat. The WD gene was assigned to rat chromosome 16 at band q12.2-q12.4 by fluorescence in situ hybridization (FISH).

Animals↗

PubMed1995

[Effect of dosing schedule on efficacy of corticosteroid inhalation in chronic asthma].

A randomized study was conducted for 4 weeks to evaluate the effect of twice daily inhalation of beclomethasone dipropionate (BDP) inhalation (group A) as compared to four times a day inhalation (group B) in chronic asthma. Patients were randomly allocated to receive BDP at a dosage of eight puffs twice daily (800 micrograms/day, group A) or four puffs four times daily (800 micrograms/day, group B). Forty four patients entered the study but eleven were excluded because of their insufficient records or unfitness to eligibility criteria. There was no significant difference in patients' characteristics such as types, and severity of diseases between the two groups. Daily keeping of symptom scores, twice daily measurement of morning and night peak expiratory flow (PEF) and checking of the drug consumption were performed throughout the study. There was no significant difference in the mean %PEF either at 2 and 4 weeks at the study between the two groups. Symptom scores, asthmatic scores, bronchial hyperresponsiveness, pulmonary function tests (FVC, FEV1, FEV1%) and serum cortisol levels also showed no significant difference between the two groups. These results indicate that twice daily inhalation of BDP (800 micrograms/day) for four weeks caused the same effects on the patients with chronic bronchial asthma as 4 times daily inhalation did. Therefore, twice daily inhalation therapy with BDP is recommended for chronic bronchial asthma patients.

Administration, Inhalation↗

PubMed1993

[A case of gastric cancer with multiple liver metastasis treated with low dose CDDP therapy on an outpatient basis after palliative gastrectomy].

A 59-year-old-male with advanced gastric cancer and multiple liver metastasis was treated by intravenous administration of MMC (30 mg/body) and oral administration of HCFU (400mg/body/day) initially after palliative gastrectomy. CT scan revealed that liver metastatic lesions were undetectable at three months after operation. Seven months later, administration of HCFU was discontinued because liver metastatic lesions were observed again. Intravenous administration of MMC (10mg/body)+ACR (20mg/body) was performed four times weekly, but liver metastatic lesions were increasing in size. From 15 months after operation intravenous administration of CDDP (25mg/body/week) was started on an outpatient basis. After administration of CDDP 6 times, liver metastatic lesions were diminished in size. By CT scan the maximum percent reduction of liver metastatic lesions was 97% and duration of partial response was seven months. Eight months later, liver metastatic lesions regrew. At 28 months after operation, the patient died of liver metastatic lesions. This low dose regimen of CDDP on an outpatient basis is potentially useful in the treatment of advanced gastric cancer with multiple liver metastasis.

Ambulatory Care↗

PubMed1992

D-lactate concentrations in blood, urine and sweat before and after exercise.

The purpose of this study was to investigate changes in the concentrations of D-lactate, L-lactate, pyruvate and methylglyoxal (MG) in body fluids after exercise. Eight untrained male students and five male students who were boat club members engaged in the exercise. Each subject performed runs of short and long duration. Compared to pre-exercise values plasma concentrations of D-lactate, L-lactate and pyruvate increased after running; in trained men by 3.6, 5.0, 3.4 times after short runs and by 1.5, 4.6, 2.0 times after long runs, and in untrained men by 3.0, 12.0, 1.6 times after short runs and 2.5, 5.6, 1.6 times after long runs, respectively. In all cases, the increase of L-lactate was always higher than that of D-lactate after running. The MG contents in red blood cells decreased markedly after running, especially in the untrained students. After short runs the MG concentration had decreased to 13% in the untrained men and 30% in the trained men, and after long runs the concentration had decreased to 41% in the untrained and 60% in the trained men. The MG in plasma and red blood cells appeared to have been utilized during relatively anaerobic exercise, especially by the untrained subjects. The D-lactate and related substances were also determined in urine, but the concentration of these substances showed no relationship to exercise. The D-lactate concentration in sweat samples tripled after short periods of running but the relative concentration to sodium ion concentration was not altered.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

Glycosidically bound sialic acid levels as a predictive marker of postoperative adjuvant therapy in gastric cancer.

A group of 293 gastric cancer patients were examined to see if the preoperative value of glycosidically bound sialic acid is a predictor of prognosis and effectiveness of postoperative adjuvant therapy. All patients had gastrectomies and were histologically confirmed to have primary adenocarcinoma of the stomach. Some patients then received either postoperative adjuvant chemotherapy or immunochemotherapy. Patients with sialic acid levels less than 74.5 mg/dl survived significantly longer than those with sialic acid levels of 74.5 mg/dl or of 85.3 mg/dl and over. No significant differences in survival were found among patients treated by gastrectomy alone, gastrectomy plus chemotherapy and gastrectomy plus immunochemotherapy. However, patients with abnormally elevated levels of sialic acid survived significantly longer when they were treated with immunochemotherapy after gastrectomy than those treated by gastrectomy alone or with chemotherapy after gastrectomy. By using Cox's multivariate regression model, pTNM stages, postoperative adjuvant therapy (chemotherapy and immunochemotherapy) and preoperative serum levels of sialic acid were examined as prognostic variables. Postoperative therapy was a significant prognostic variable in patients with abnormally elevated levels of sialic acid. The preoperative serum level of sialic acid is a promising predictive marker of the response to postoperative adjuvant immunochemotherapy.

Adult↗

PubMed1992

Successful arterial embolization of arteriovenous fistula in the portal circulation.

We successfully performed arterial embolization of an arteriovenous fistula between the left gastric artery and vein. The increased blood flow in the portal vein via the left gastric vein and the arteriovenous fistula induced severe portal hypertension. After obliteration of the left gastric artery, the arteriovenous fistula was not opacified on angiography and the portal hypertension improved.

Arteriovenous Fistula↗

PubMed1992

Concentrations of D-lactate and its related metabolic intermediates in liver, blood, and muscle of diabetic and starved rats.

This is a report investigating the methylglyoxal (MG) bypass in animals, by which D-lactate is produced from triosephosphate via MG. Rats were made diabetic using streptozotocin or starved for 72 h. D-Lactate and various metabolites related to it, such as L-lactate, pyruvate, methylglyoxal, glucose, and inorganic phosphate, were measured in the blood plasma, liver, and skeletal muscle of the rats. Diabetic and starved rats had significantly higher levels of D-lactate in plasma, liver, and skeletal muscle compared with the control group. In contrast, pyruvate levels in plasma, liver, and skeletal muscle was markedly lower than normal in diabetic and starved rats. L-Lactate level lowered markedly in plasma, liver, and skeletal muscle of starved rats and elevated in liver of diabetic rats. Differences between plasma L-lactate level for diabetes and control were not significant. MG level was significantly elevated in plasma and depressed in livers and muscles of starved rats as well as livers of diabetic rats. Hepatic glycerol content was markedly increased in those states. Enzyme activities related to D- and L-lactate, such as pyruvate kinase, phosphofructokinase, aldolase, and glyoxalase I, were measured in the livers of these rats. Pyruvate kinase activity decreased in these states, but other enzyme activities showed no significant changes. D-Lactate was much more excreted than L-lactate in the urine of diabetic and fasted rats compared with normal rats.

Animals↗

PubMed1992

Adult T-cell leukemia/lymphoma (lymphoma type) with remarkable gastric lesions: a case report.

We report a case of a 53-year-old woman with adult T-cell leukemia/lymphoma (ATL) (lymphoma type) with multiple gastric lesions, admitted to our hospital because of systemic lymphadenopathy and epigastralgia. Gastroscopy showed a variety of gastric lesions including thickened folds, ulcerations and polypoid lesions. Biopsy specimens obtained from the stomach and lymph nodes revealed diffuse infiltration of pleomorphic mononuclear cells and the integration of HTLV-1 proviral DNA. We demonstrated through the investigation of 30 previously reported cases of ATL that this is a rare case of the lymphoma type of ATL presenting remarkable gastric lesions.

Blotting, Southern↗

PubMed1992

A convenient method for regional monoamine oxidase-A determination by [14C]clorgyline autoradiography.

The availability of clorgyline for regional monoamine oxidase-A (MAO-A) determination was examined using [14C]clorgyline in rat. [14C]Clorgyline was synthesized by the methylation reaction of N-desmethyl-clorgyline and [14C]methyliodide in dimethylformamide with high radiochemical yield. The MAO-A distribution map by autoradiography correlated with that by histochemical technique and its quantity was consistent with the calculated MAO-A amount based on previous reports. The combination of labeled clorgyline and autoradiographic technique will promise the quantitative measurement of regional MAO-A distribution.

Animals↗

PubMed1992

Age-related decline of cerebral oxygen metabolism in normal population detected with positron emission tomography.

Using positron emission tomography (PET), cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) were measured in 32 healthy volunteers aged from 27 to 67 years. In bilateral putamen, left supratemporal, left infrafrontal and left parietal cortices, CMRO2 showed a significant decline during aging. The age-related decline of CBF was seen only at the left superior temporal cortex. The mean CMRO2 was significantly lower in the elder group (over 51 years old) than in the younger group (under 50 years old), whereas no significant difference in mean CBF between the two groups. The poor correlation of CBF to the age could be explained partly by the fact that CBF is easily influenced by the physiological, psychological and/or environmental factors. The age-related changes of CMRO2 were more marked in the association cortices of the left hemisphere than in that of the right hemisphere.

Adult↗

PubMed1992

Platelet-activating factor in bronchoalveolar lavage fluid of patients with adult respiratory distress syndrome.

1. To clarify the role of platelet-activating factor (PAF) in the development of adult respiratory distress syndrome (ARDS), we performed bronchoalveolar lavage (BAL) in 19 patients with ARDS and examined cell populations, albumin concentrations and PAF levels. PAF levels were measured by a newly developed radioimmunoassay. 2. In the BAL fluid of ARDS patients, neutrophil percentages and albumin concentrations markedly increased compared with control subjects. 3. PAF was detected in 14 of 19 patients with ARDS, whereas it did not exist in the control subjects. 4. Furthermore, we investigated the priming effect of recombinant human tumour necrosis factor-alpha (TNF alpha), which is known to be one of the most important mediators in the development of ARDS, on PAF production induced by the calcium ionophore in neutrophils. 5. Pre-incubation with TNF alpha dose-dependently increased both extracellular and intracellular PAF production in neutrophils. 6. These results suggest that PAF might play an important role in the development of ARDS.

Adolescent↗

PubMed1992

7S collagen in bronchoalveolar lavage fluid of patients with adult respiratory distress syndrome.

To evaluate the disruption of the basement membrane in the pathogenesis of adult respiratory distress syndrome (ARDS), we measured the level of 7S collagen in the bronchoalveolar lavage (BAL) fluid of patients with ARDS and normal control subjects by using a radioimmunoassay method. Twelve of 14 patients with ARDS had evidence of 7S collagen in the BAL fluid, but no 7S collagen was detected in the BAL fluid of the controls. The mean 7S collagen concentration of the BAL fluid in patients with ARDS was 19.6 +/- 9.4 ng/ml. In patients with ARDS, the BAL levels of 7S collagen correlated strongly with neutrophil counts (r = 0.813; p less than 0.01) and with elastase-complex (r = 0.914; p less than 0.01). We conclude that 7S collagen may be an index of leukocyte-mediated lung injury in patients with ARDS, and detection of 7S collagen in BAL fluid is useful for evaluating the disruption of basement membrane.

Adult↗

PubMed1992

[A case of bronchiolitis obliterans organizing pneumonia in a patient with rheumatoid arthritis who responded to corticosteroid and immunosupressant therapy].

A 56-year-old man with rheumatoid arthritis was admitted to our hospital with dyspnea on exertion, fever and right chest pain. Chest X-ray showed bilateral, predominantly lower interstitial shadows and right pleural effusion. Open lung biopsy specimen showed bronchiolitis obliterans organizing pneumonia (BOOP) with prominent alveolitis, and corticosteroid therapy was introduced. Because the patient showed little response to corticosteroids, an immunosupressant (cyclophosphamide) was added. There was marked clinical, physiological and roentgenographic improvement in response to combined therapy. The therapeutic response of some BOOP patients seems to vary according to its pathogenesis and pathological findings, and these should be taken into consideration in the selection of therapeutic strategies.

Adrenal Cortex Hormones↗

PubMed1991

Fluorimetric and high-performance liquid chromatographic determination of D-lactate in biological samples.

D-Lactate in biological samples was converted into a strongly fluorescent substance in a one-vial reaction. It was first converted into the pyruvate hydrazone in the presence of D-lactate dehydrogenase, an NADH-reoxidation system using diaphorase, D,L-6,8-thioctamide and hydrazine. This hydrazone was then converted into 2-hydroxy-6,7-dimethoxy-3-methylquinoxaline by 1,2-diamino-4,5-dimethoxybenzene in 1 M hydrochloric acid, and the quinoxaline was extracted and measured fluorimetrically at 432 nm (excitation at 365 nm). The calibration curve for D-lactate was linear up to at least 100 nmol/ml of the assay mixture, with a determination limit of 2 nmol/ml. The quinoxaline was also analysed by high-performance liquid chromatography with fluorimetric detection. The calibration curve for D-lactate was linear from 500 fmol to 75 nmol in the reaction mixture. This method was 4000 times more sensitive than the fluorimetric method, and could determine D-lactate in blood plasma volumes of less than 1 microliter.

Animals↗

PubMed1991

Filter characteristics of cercal afferents in the cockroach.

The response dynamics of cercal afferents in the cockroach. Periplaneta americana, were determined by means of a cross-correlation technique using a Gaussian white noise modulation of wind as a stimulus. The white noise stimulus could evoke sustained firing activity in most of the afferents examined (Fig. 1). The spike discharges were unitized and then cross-correlated with the stimulus to compute 1st- and 2nd-order Weiner kernels. The 1st-order kernels from a total of 28 afferents were biphasic and closely matched the time differential of a pulse (Figs. 1, 3 and 4). The amplitude and waveform of the kernels depended on the stimulus angle in such a way that the kernels were the mirror image of those on the polar opposite side (Figs. 2 and 3). The 2nd-order kernels were also differential. They had 2 diagonal peaks and 2 off-diagonal valleys in a 2-dimensional plot with 2 time axes (Figs. 1, 5 and 6). This 4-eye configuration was basically invariant irrespective of the stimulus angle, although the kernels varied in amplitude when the stimulus angle was changed. The time between the peak and a following trough of the 1st-order kernel was constant and had a mean of 4.6 +/- 0.1 ms, whereas the time between 2 diagonal peaks of the 2nd-order kernels was 4.7 +/- 0.1 ms (Figs. 4 and 6), suggesting that wind receptors (filiform sensilla) on cerci act as a band-pass filter with a peak frequency of about 106 Hz. The peak time, however, varies from 2.3 to 6.9 ms in both kernels, which may reflect the spatial distribution of the corresponding hairs on the cercus. The summation of the 1st- (linear) and 2nd-order (nonlinear) models precisely predicted the timing of the spike firing (Fig. 8). Thus, these 2 lower-order kernels can totally characterize the response dynamics of the wind receptors. The nonlinear response explains the directional sensitivity of the sensory neurons, while the differentiating 1st-order kernel explains the velocity sensitivity of the neurons. The nonlinearity is a signal compression in which one of the diagonal peaks of the 2nd-order kernel always offsets the downward phase of the 1st-order kernel (Fig. 7) and obviously represents a half-wave rectification property of the wind receptors that are excited by hair movement in only one direction and inhibited by hair movement in the polar opposite direction.

Animals↗