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Biomedical subjects

T Kuroume

Publications and source records attributed to T Kuroume.

At least 19 recordsLinked to original sources
PubMed1998

Dipole analysis of epileptic source generator with manual zero potential shifting method.

The dipole tracing method is a technique whereby an electric source generator is estimated as an equivalent current dipole (ECD) based on potential distribution on the scalp. To estimate the electric source generator of low amplitude spikes, a manual zero potential shifting (MZPS) method was introduced in which a zero potential is set manually in dipole analysis. The subjects were three patients with localization-related epilepsy with temporal spikes. When low-amplitude spikes (< 50 microV) were analyzed by the conventional mean zero potential method, the dipolarity, an indicator of ECD reliability, had a low value and its locations were scattered. In contrast, when these low-amplitude spikes were analyzed by the MZPS method, ECD showed a high dipolarity value comparable to that obtained when high-amplitude spikes (> or = 50 microV) were analyzed by the mean zero potential method. Furthermore, the locations of the former ECD tended to converge and were almost identical to those of the latter ECD. These findings suggest the usefulness of the MZPS method in dipole analysis in terms of the dipolarity and ECD locations of low-amplitude spikes.

Action Potentials↗
PubMed1995

Relationship between ultrasonically nebulized distilled water-induced bronchoconstriction and acetic acid-induced cough in asthmatic children.

BACKGROUND: Although wheezing and cough are the most common complaints in asthmatic persons, the mechanisms of hyperresponsiveness to bronchoconstriction and cough are nevertheless still unclear. OBJECTIVE: To investigate the common mechanisms between them, we studied the relationship between ultrasonically nebulized distilled water (UNDW) inhalation challenge and acetic acid (AA) inhalation challenge. In addition, we evaluated the effect of inhaled furosemide on both provocation tests by means of a placebo-controlled study. METHOD: In study 1 the UNDW, AA, and histamine inhalation challenges were performed in 40 asthmatic children (26 boys, aged from 7 to 16 years; mean +/- SD, 11.2 +/- 2.0 years). In study 2, 12 of the study 1 subjects (9 boys, 11.3 +/- 2.4 years) were subjected to each challenge test after inhalation of furosemide (10 mg/body square meters), or placebo (0.9% saline solution) on separate days. RESULTS: There was a good correlation between the provocative dose causing a 20% fall in forced expiratory volume in 1 second in the UNDW inhalation challenge (UNDW-PD20) and threshold dose causing cough in the AA inhalation challenge (R = 0.527; p < 0.001). There was no relationship either between UNDW-PD20 and the provocative concentration causing a 20% fall in the histamine inhalation challenge (histamine-PC20)(R = 0.384; p > 0.1), or between histamine-PC20 and the cough threshold (R = 0.308; p > 0.05). In study 2 neither bronchoconstriction nor bronchodilation after inhalation of furosemide was observed. Inhaled furosemide exerted a protective effect on UNDW-PD20 and cough threshold of the AA inhalation challenge (p < 0.01 and p < 0.01, respectively), but did not attenuate histamine-PC20 (p > 0.1). CONCLUSION: These data suggest that a common mechanism may cause hyperresponsiveness against both UNDW-induced bronchoconstriction and AA-induced cough in asthmatic children.

Acetates↗
PubMed1995

Postnatal changes in size and actomyosin content of rabbit gastric myocytes.

Maximal tension generated by gastric muscle is three to four times greater in weanlings than in newborn rabbits. To determine if this functional maturation is accompanied by structural changes, we compared length-tension relationships, myocyte number and size, and actomyosin content in muscle from the gastric body of newborn (1 day) and weanling (12 weeks) rabbits. Passive tension at optimal length (Lo) was six times greater in circular smooth muscle strips from weanling rabbits than from newborn rabbits. Active tension at Lo in weanling rabbits was three times greater than in newborn rabbits. For morphometry, muscle cross-sections stretched to Lo in the circular axis were photographed with electron microscopy (5300x). Cell number/unit area was counted in circular muscle layers from newborns and weanlings. Cross-sectional area of each cell was measured by computerized planimetry. There were 2.5 times more cells per unit area in newborn than in weanling tissue, P < 0.001. However, the mean cell area in newborns (5.4 +/- 4.6 microns2) was less than that in weanlings (13.5 +/- 11.7 microns2). Consequently, the muscle cells occupied similar total areas in newborns and weanlings. We measured actin and myosin heavy chain in full-thickness muscle homogenates using SDS gel electrophoresis and densitometric scanning. Actin and myosin concentrations were lower in newborns (9.6 +/- 1.3 micrograms g-1 wet weight and 5.6 +/- 0.7 micrograms g-1 wet wt, respectively) than in weanlings (17.7 +/- 3.0 micrograms g-1 wet wt and 8.2 +/- 1.6 micrograms g-1 wet wt respectively), each P < 0.01. The proportion of myosin heavy chain isozymes did not change with age. We conclude that there are postnatal increases in cell size and the quantity of actin and myosin in rabbit gastric muscle. The increase in quantity of contractile protein may be in part responsible for age-dependent increases in maximal tension.

Actomyosin↗
PubMed1995

Inhaled indomethacin prevents bronchoconstrictive response to distilled water but not to histamine in children with asthma.

We evaluated the effect of inhaled indomethacin, a nonsteroidal antiinflammatory drug (NSAID), against bronchoconstriction induced by ultrasonically nebulized distilled water (UNDW) in children with asthma. Ten children with asthma (eight males and two females, with a mean +/- SEM age of 10.7 +/- 0.7 yr), who had a decrease in FEV1 of at least 20% after UNDW inhalation, were enrolled in this study. These subjects were pretreated with inhaled indomethacin (3 mg/m2 body-surface area) or placebo (0.9% saline) according to a single-blind, randomized, crossover design, and underwent a UNDW challenge test 15 min after the pretreatment. Furthermore, to study the possibility that indomethacin has a direct effect on airway smooth muscle, bronchial provocation with histamine was performed in seven subjects on two further days after pretreatment with indomethacin or placebo. Inhaled indomethacin had no effect on baseline pulmonary function, but did prevent the UNDW-induced decline in FEV1 (p < 0.01). Inhaled indomethacin did not modify the bronchoconstrictor response to histamine, indicating that a direct effect of this agent on airway smooth muscle is unlikely. The inhibition of local prostaglandin synthesis in the airways may be involved in the effect of indomethacin.

Administration, Inhalation↗
PubMed1995

Inhaled diuretics attenuate acid-induced cough in children with asthma.

To evaluate the effect of inhaled diuretics, furosemide and amiloride, on cough induced by acid inhalation challenge in asthmatic children, a double-blind, randomized, placebo-controlled study was conducted. On separate days, 12 asthmatic children (10.3 +/- 0.7 [SEM] years) underwent acetic acid (AD) inhalation challenge after inhalation of furosemide (10 mg/m2 of body) amiloride (0.3 mg/m2 of body), or placebo (0.9% saline solution). Bronchoconstriction was not observed after administration of furosemide and amiloride. Both inhaled furosemide and amiloride exerted a protective effect against AA-induced cough in asthmatic children (p < 0.01 and p < 0.05, respectively), while there was little correlation between the individual protective potency of furosemide and amiloride against AA-induced cough (rs = 0.344, p = 0.255). These results demonstrate that both furosemide and amiloride can attenuate AA-induced cough, although, this protective effect of inhaled diuretics may not necessarily be dependent on Na(+)-K(+)-Cl- cotransporter or Na+ channel in airway epithelial cells.

Acetates↗
PubMed1995

Cytolytic action of stored human milk on blood cells in vitro.

Stored human milk induced cytolysis on various types of blood cells depending on the storage time and temperature. When separated by centrifugation after storage for 24 h at 4 degrees C, the cream, not whey, induced cytolysis. When separated and heated for 30 min at 56 degrees C before storage, neither cream or whey induced cytolysis. When the cream was heated at 56 degrees C for 30 min and mixed with non-heat-treated whey before being storage for 24 h at 4 degrees C, it induced cytolysis. When bile salt was added to whole milk before storage, the cytolytic activity was enhanced. When eserine was added, the cytolytic activity was suppressed. Thin layer chromatography showed that stored milk, not fresh milk, contained free fatty acids which caused a similar degree of cytolysis as stored whole milk. These results indicated that the cytolysis is due to the free fatty acids which were produced from triglycerides catalyzed by the lipase in milk.

Animals↗
PubMed1995

Clinical and immunologic surveys of Hymenoptera hypersensitivity in Japanese forestry workers.

BACKGROUND: The increased incidence of bee-sting allergy among beekeepers is well known, whereas Hymenoptera hypersensitivity among forestry workers, who are frequently stung by Hymenoptera, is not well understood. OBJECTIVE: To elucidate the nature of Hymenoptera hypersensitivity among forestry workers and analyze the mechanism involved in Hymenoptera-induced systemic reactions. METHODS: A questionnaire was administered and yellow jacket venom-specific IgE antibody titers measured in 323 forestry workers and 100 age-matched office workers with little occupational exposure to Hymenoptera stings as a control group. RESULTS: From the questionnaire it was found that the percentage of systemic reactions to Hymenoptera stings was significantly greater in the forestry workers than in the control subjects (P < .01). The number of sting exposures was significantly higher in the forestry workers than in the control subjects (P < .01) and was closely correlated with episodes of systemic reaction. Yellow jacket venom-specific IgE antibody titers were significantly higher in forestry workers with episodes of systemic reaction compared with those with only local or large local reactions to Hymenoptera (P < .05), although more than half of these subjects had undetectable IgE antibody titers to yellow jacket venom. IgE antibody titers against yellow jacket venom were closely correlated with those of paper wasp (rs = .802, P < .001), which is another frequent source of Hymenoptera stings. In workers with episodes of sting exposure within the most recent 3 years, the period from the last sting was not correlated with yellow jacket venom-specific IgE antibody titers. CONCLUSIONS: The number of sting exposures may contribute to systemic reactions to Hymenoptera sting, and some mechanism other than IgE mediated hypersensitivity may also be involved in Hymenoptera-induced systemic reactions.

Adult↗
PubMed1994

The effect of non-steroidal anti-inflammatory drugs on the electrical properties of cultured dog tracheal epithelial cells.

The effect of non-steroidal anti-inflammatory drugs (NSAIDs) on the electrical properties of primary cultures of dog tracheal epithelium has been studied. The cells used were grown with an air interface in a serum-free medium on membranes coated with human placental collagen. When mounted in Ussing chambers at 37 degrees C, mean values for the baseline short circuit current (Isc) and the transepithelial resistance of 65 tissue specimens from 18 dogs were 24.0 +/- 3.2 microA/cm2 and 458 +/- 128 omega.cm2, respectively. These tissues had been pretreated with amiloride to abolish active Na+ absorption. Under these conditions, the Isc value serves as a measure of active Cl- secretion. The results of this study revealed that the Isc across a cultured monolayer of trachea was attenuated by the tested NSAIDs, indomethacin, fulfenamic acid, mefenamic acid, aspirin, and acetaminophen, with Ki's that ranged from 6.0 x 10(-5) to 2.51 x 10(-3) M. Salicylic acid had no effect on baseline Isc. The Isc sensitivity sequence to the Cl- channel inhibitors tested was: fulfenamic acid >> indomethacin > mefenamic acid >> aspirin > acetaminophen > salicylic acid. The NSAIDs also significantly inhibited both the transient, Ca(2+)-dependent and the sustained, cAMP-dependent increases in Isc elicited by isoproterenol. Thus, the tested NSAIDs appeared to have an effect on the electrical properties of the cells. A similar effect of NSAIDs on ion transport across the human airway epithelium may help to reduce airway fluid secretion.

Animals↗
PubMed1994

Cytokine profile during high-dose rhG-CSF therapy in severe congenital neutropenia.

The effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on cytokine profile was evaluated in a case of severe congenital neutropenia. The plasma levels of cytokines were measured before and during rhG-CSF therapy. These included G-CSF, granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-1 alpha, interleukin-1 beta, interleukin-2 (IL-2), interleukin-3 (IL-3), interleukin-4, interleukin-6 (IL-6), and tumor necrosis factor-alpha. Soluble interleukin-2 receptor (sIL-2R) was measured serially during rhG-CSF therapy. Lymphocyte subpopulations including CD2, CD3, CD4, CD8, CD19, CD20, and CD25 were also measured, rhG-CSF was administered once daily as a 30-min infusion. The patient was treated with increasing dose levels of 100, 200, 400, 800, and 1,600 micrograms/m2/day. The level of endogenous G-CSF was elevated to 334 pg/ml before treatment and GM-CSF, IL-2, IL-3, and IL-6 were slightly elevated. Clinically, he showed a moderate response to a high dose of rhG-CSF (1,600 micrograms/m2/day). Plasma levels of G-CSF markedly increased during therapy but plasma levels of other cytokines did not show significant changes during therapy and lymphocyte subpopulations did not significantly change. A drastic increase in sIL-2R expression was observed after rhG-CSF infusion and an increase in sIL-2R expression occurred even before a major increase in granulocyte counts. These results showed that a high dose rhG-CSF therapy may influence the cytokine network as judged by the increased sIL-2R expression.

Child, Preschool↗
PubMed1994

Cough variant asthma: a case study with antigen, histamine and methacholine inhalation challenge tests.

This paper presents a 7 year old girl with cough variant asthma, in which house dust challenge test provoked fine crackles on auscultation without any changes of lung function test. Pretreatment with DL-chlorpheniramine maleate for 7 days inhibited the appearance of fine crackles. On histamine inhalation test, fine crackles and rhonchi appeared on auscultation without bronchoconstriction (% fall of one-second forced expiratory volume < 10%). These data suggest that the cause of cough variant asthma is mainly an immunoglobulin E-mediated allergic reaction in the mucus secreting system.

Asthma↗
PubMed1994

Effects of cilostazol, a cyclic nucleotide phosphodiesterase III inhibitor, on substance P-induced airflow obstruction and airway microvascular leakage in guinea pigs.

We studied the effect of cilostazol, a cyclic nucleotide phosphodiesterase (PDE) III inhibitor, on a substance P (SP)-induced increase in lung resistance and in airway microvascular leakage in guinea pigs in vivo. Four minutes after intravenous (i.v.) administration of cilostazol (1.5 and 5 mg/kg) or vehicle, Evans blue dye (20 mg/kg) was given i.v. One minute later, 30 nmol/kg SP was administered i.v. The SP-induced increase in lung resistance was measured for 6 min. Following the measurement of lung resistance, microvascular leakage at the trachea, main bronchi and intrapulmonary airways was also examined. Cilostazol attenuated the SP-induced increase in lung resistance, with a significant inhibition at the concentration of 5 mg/kg. Five milligrams per kilogram cilostazol also significantly inhibited SP-induced Evans blue dye extravasation at the trachea and main bronchi. These results suggest that cilostazol might reduce airflow obstruction which is seen in diseases such as asthma through attenuation of bronchoconstriction and, possibly, airway edema resulting from airway microvascular leakage in man.

Airway Obstruction↗
PubMed1994

Reversed-phase high-performance liquid chromatography for analysis of urinary proteins: diagnostic significance of alpha 1-acid glycoprotein.

In order to analyze urinary proteins from patients with various renal diseases, a reversed-phase high-performance liquid chromatography with IPG PACK ODS column packed with polyporous glass was employed. The peak areas of alpha 1-acid glycoprotein (alpha 1-AGP), beta 2-microglobulin (beta 2-MG) and albumin were measured by a chromato-integrator. The alpha 1-AGP/albumin ratio was regarded as the marker of glomerular damage, while the beta 2-MG/albumin ratio indicated tubular dysfunction. As a result, the alpha 1-AGP/albumin ratio in the urine from patients with either various glomerulonephritis (GN) or idiopathic nephrotic syndrome was significantly higher than that from either patients with postural proteinuria or healthy children. However, the beta 2-MG/albumin ratio in the urine from patients with GN was the same level as controls. The beta 2-MG/albumin ratio was elevated only in urine from patients with tubular dysfunctions. These data suggest that the urinary alpha 1-AGP/albumin ratio could be a beneficial indicator in locating patients with GN from among children with asymptomatic proteinuria.

Albuminuria↗
PubMed1994

Purification of two types of TNF inhibitors in the urine of the patient with chronic glomerulonephritis.

In order to clarify whether TNF inhibitory activity in the urine of glomerulonephritis (GN) patients depends on the existence of TNF inhibitors/soluble TNF receptors, we purified two types of TNF inhibitors from the urine of chronic renal failure (CRF) with GN patient. Using four steps of chromatography (anion exchange chromatography, preparative reverse phase chromatography, TNF affinity chromatography, analytical reverse phase chromatography), two types of 99% pure TNF inhibitors were purified. Amino terminal amino acid sequence revealed that one inhibitor was identical to soluble TNF receptor, p55, however, the other was homologous but not identical to soluble TNF receptor, p75. Our experiments demonstrated that TNF inhibitory activity in the urine of CRF patients depended partly on the existence of soluble TNF receptors in the urine.

Amino Acid Sequence↗
PubMed1994

Fibronectin synthesis bioactivity in human breast milk.

To evaluate the effect of milk feeding on fibronectin in the perinatal period, fibronectin synthesis bioactivity (FnSA) in human breast milk was examined. FnSA was measured by bioassay using the cell-lined fibroblast. For the characterization of the FnSA, the milk samples were chromatographed. In gel chromatography (Sephadex G-100), three fractions of FnSA were detected. Two fractions overlapped with those of immunoreactive epidermal growth factor (ir-EGF). The other was present in the low-molecular-weight portion. In the high-performance liquid chromatography, two of four fractions with FnSA presented ir-EGF. One of two fractions with FnSA in heparin-binding affinity chromatography almost coincided with the portions of basic brain fibroblast growth factor (ir-bFGF). From these findings, we speculated that human milk has the bioactivity of fibronectin synthesis and it is composed of EGF, FGF, and unknown low-molecular-weight factors. Although the clinical meanings of FnSA have not been clarified, our data indicate a new characteristic of human milk.

Biological Assay↗
PubMed1994

Effect of inhaled amiloride on water-induced bronchoconstriction in asthmatic children.

To determine whether the inhaled diuretic, amiloride, can modify bronchoconstriction induced by ultrasonically nebulized distilled water (UNDW) in asthmatic children, a double-blind, randomized, placebo-controlled study was done. The UNDW inhalation challenge was performed in 12 asthmatic children (nine boys and three girls; mean age +/- SEM, 11.2 +/- 0.75 yr), who had at least a 20% fall in FEV1 after UNDW inhalation. On separate days, these subjects underwent UNDW inhalation challenge after inhalation of amiloride (0.3 mg/m2 body surface area) or placebo (0.9% saline). Neither bronchodilation nor bronchoconstriction after amiloride inhalation was observed. The mean value and SEM of the UNDW PD20 after placebo inhalation was 4.55 +/- 0.80 ml. After inhalation of amiloride, PD20 increased to 7.93 +/- 0.75 ml (p < 0.01). We concluded that inhaled amiloride exerted a protective effect against UNDW-induced bronchoconstriction in asthmatic children.

Administration, Inhalation↗
PubMed1994

P300 event-related potentials in epileptic children.

To evaluate the cognitive function of epileptic children, we examined P300 in 50 patients, 32 with idiopathic generalized epilepsy (IGE) and 18 with temporal lobe epilepsy (TLE), and 39 normal children. There were significant negative correlations between age and P300 latencies at Pz and Cz in normal controls. For data analysis, we used the age-corrected latency, which was calculated as the interval between the actual and predicted P300 latencies. The predicted latency was calculated with the regression equation as the relationship between P300 latency and age in normal controls. The age-corrected P300 latencies recorded from Pz and Cz were significantly longer in patients with IGE (41.5 +/- 13.1, 42.0 +/- 12.5) than in control subjects (0 +/- 7.5, 0 +/- 7.9). There were no significant differences in age-corrected P300 latencies between patients with TLE (21.2 +/- 17.6, 31.5 +/- 17.0) and controls, or IGE and TLE. Recently, it was considered that the mesencephalic reticular formation and thalamus may play major roles in the genesis of generalized epilepsy, so we speculate that dysfunction of these systems may contribute to the prolongation of P300 in children with idiopathic generalized epilepsy.

Adolescent↗