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Biomedical subjects

K Konno

Publications and source records attributed to K Konno.

At least 235 records · Page 13Linked to original sources

Stimulation of Na absorption by the antiasthmatic kampo drug Saiboku-to in cultured airway epithelium.

To study the effect of the Kampo drug Saiboku-to (TJ-96) on ion transport function of airway epithelial cells, we studied bioelectric properties of cultured tracheal epithelium from dogs under short-circuit conditions in vitro. Addition of TJ-96 (1 mg/ml) to the mucosal solution of the Ussing chamber increased the epithelial short-circuit current (SCC) from 6.5 +/- 0.7 to 11.4 +/- 1.6 microA/cm2 (P less than 0.001). This effect was dose-dependent, with the maximal increase from the baseline value and the concentration required to produce a half-maximal effect (EC50) being 70.5 +/- 12.6% (P less than 0.001) and 3 micrograms/ml, respectively; and there were corresponding increases in transepithelial potential difference and cell conductance. Submucosal addition of TJ-96 likewise increased SCC, although the magnitude of the response was smaller as compared with the response to the mucosal addition. The TJ-96-induced increase in SCC was not affected by diphenylamine-2-carboxylate or furosemide but abolished by amiloride. Intracellular cyclic AMP levels were dose-dependently increased by TJ-96. These results indicate that TJ-96 may selectively stimulate Na absorption across the tracheal epithelium, probably through intracellular accumulation of cyclic AMP.

Animals↗

Lung cancer in patients with idiopathic pulmonary fibrosis.

We investigated lung cancer in 99 patients with idiopathic pulmonary fibrosis (IPF). Lung cancer was found in 31 (31.3%) of 99 patients with IPF. Most (87.9%) tumors, including squamous cell carcinoma, were observed in the peripheral region of the lung, whereas the distribution of histologic types of cancers was similar to that seen in ordinary lung cancer. Peripheral tumors were frequently seen in the lower lobe, where fibrotic shadow was prominent. However, the severity of fibrosis was not related with the prevalence or histologic type of lung cancer. Two-thirds of IPF patients having a smoking history of over 40 years developed lung cancer. When compared with nonsmoking IPF control subjects, the relative risk of smoking in IPF patients was 3.5, identical with that reported for smokers in the general population. We suggest that smoking in patients with IPF is an additive risk factor for the development of lung cancer. We also speculate that the high prevalence of peripheral squamous cell carcinoma might be associated with cigarette smoking.

Aged↗

Multiple forms of mammalian sialidase: altered expression in carcinogenesis.

We have demonstrated that rat liver contains at least four types of sialidase differing in subcellular location, in catalytic property and immunologically. They are intralysosomal, cytosolic and membrane-associated sialidases I and II. Membrane sialidase I locates mainly in plasma membrane and sialidase II in lysosomal membrane. Immunological study reveals that the same types of sialidase exist in various tissues of rat and of other mammalian species. Based on these results, we examined the sialidases in rat hepatomas and in transformed cells of JB6 mouse epidermal cell. Hepatomas were found to possess four types of sialidase and the three of them altered quantitatively. Intralysosomal sialidase activity was higher but cytosolic and lysosomal membrane sialidase activities were lower in hepatomas than in control liver. When the sialidases of transformants of JB6 cells were compared with those of control cells, the activities of two lysosomal sialidases were decreased and contrarily plasma membrane sialidase was increased. We discussed a possible significance of the sialidase alterations in carcinogenesis.

Animals↗

[Effect of diaphragmatic fatigue on ventilatory response to carbon dioxide].

To clarify the effect of respiratory muscle fatigue on ventilatory response to carbon dioxide, we performed CO2 rebreathing study before and after diaphragmatic fatigue in nine healthy males. Diaphragmatic fatigue was induced by inspiratory resistor loading and confirmed by the increase in Tension Time Index and the decrease in Pdi max at FRC. The effects of diaphragmatic fatigue were as follows: 1) S and B value of VE-CO2 curve did not change. 2) P1-CO2 curve shifted to the left but the slope of the curve did not change. 3) delta Ppl response to CO2 decreased, but delta Pdi response to CO2 did not change. 4) The increase in respiratory accessory muscle EMG was more prominent, compared to diaphragmatic EMG. 5) Rib cage movement became more marked. In conclusion, diaphragmatic fatigue (with 60 percent decrease in Pdi max at FRC) does not affect on ventilatory response to carbon dioxide. To maintain the homeostasis of the chemical ventilatory feedback system, diaphragmatic dysfunction is compensated by the increased activity of respiratory accessory muscles with possible increase in neural drive.

Adult↗

[Effects of angiotensin peptides on airway epithelial ion transport and its modulation by angiotensin converting enzyme].

To study the effects of angiotensin (ANG) peptides on airway epithelial ion transport function, we evaluated the bioelectric properties of canine cultured tracheal epithelium under short-circuit conditions in vitro. Addition of ANG I, II and II dose-dependently increased short-circuit current (Isc) and transepithelial potential difference, an effect that was more pronounced with addition to the submucosal solution than to the mucosal solution, with rank order of potency of ANG II greater than or equal to ANG II much greater than ANG I. The ANG-induced increase in Isc was not altered by the Na channel blocker amiloride, but was greatly reduced by the CI channel blocker diphenylamine-2-carboxylate and Cl-free medium. The response of Isc to ANG I was reduced by MK422, an angiotensin converting enzyme inhibitor, in a dose-dependent fashion. These results suggest that ANG II and III selectively stimulate Cl secretion across airway epithelium and that ANG I may exert its effect after its conversion to ANG II by angiotensin converting enzyme.

Angiotensin I↗

Effects of angiotensin peptides on cholinergic neurotransmission in rabbit tracheal smooth muscle.

To determine the effects of angiotensins I, II, and III (A I, A II, and A III) on airway smooth muscle functions, we studied isolated tracheal segments from rabbits under isometric conditions in vitro. Addition of A II and A III but not A I potentiated the contractile response to electrical field stimulation (EFS) at 5 Hz in a dose-dependent fashion. The frequency-response curves for EFS were displaced to the left by A II and A III, whereas the contractile responses to exogenous acetylcholine remained unchanged. Angiotensin-induced potentiation of the response to EFS was further increased in the presence of physostigmine. These results suggest that A II and A III may prejunctionally potentiate the vagally-mediated contraction of airway smooth muscle.

Acetylcholine↗

[Airway epithelial beta 3-adrenergic receptor--effect on bioelectric properties and its mechanism of action].

To characterize the "atypical" beta-adrenergic receptor (beta 3-adrenergic receptor) and its action on ion transport across airway mucosa, we measured the bioelectric properties of canine cultured tracheal epithelium under short-circuited conditions in vitro. Submucosal but mucosal addition of BRL37344, a selective beta 3-adrenergic agonist, increased short-circuit current (Isc) in a dose-dependent fashion, the EC50 value being 30 fold higher than that of isoproterenol. This effect on Isc was accompanied by the accumulation of intracellular cyclic AMP, and it was abolished by diphenylamine-2-carboxylate, bumetanide, and Cl-free medium, but not by amiloride. Pretreatment of cell with beta 1- and beta 2-adrenergic antagonists greatly reduced the Isc response to isoproterenol, whereas it had little effect on the BRL37344-induced response. In addition, the increase in Isc produced by BRL37344 was competitively antagonized by cyanopindolol, but pA2 was significantly different from the case of isoproterenol. These results suggest that beta 3-adrenergic receptors exist on airway epithelium, and may stimulate Cl secretion across the airway mucosa via accumulation of intracellular cyclic AMP.

Adrenergic beta-Agonists↗

[Pharmacological evidence for the existence of beta 3-adrenergic receptors in canine airway smooth muscle].

There is increasing evidence for the existence of a third atypical beta-adrenergic receptor (beta 3-adrenoceptor) in various tissues including adipocytes, cardiac myocytes and intestinal smooth muscle preparations. In the present study, to determine whether beta 3-adrenoceptors also exist in the airway smooth muscle, we studied isolated bronchial segments from dogs under isometric conditions in vitro. Application of beta-adrenoceptor agonists produced a concentration-dependent relaxation of tissues precontracted with 10(-5) M acetylcholine, the order of potency being isoproterenol (1) > or = salbutamol, a beta 2-selective adrenoceptor agonist (0.95) > or = BRL 37344, a beta 3-selective adrenoceptor agonist, (0.83) >> norepinephrine (0.10). Under the condition in which alpha- and beta 1-adrenoceptors had been blocked by phentolamine and ICI 89406, respectively, the relaxant response to salbutamol was competitively antagonized by the beta 2-adrenoceptor antagonist ICI 118551, and the pA2 value was 7.01 +/- 0.25 (mean +/- SE), whereas the response to BRL 37344 was resistant, with of apparent pA2 value of 5.66. However, cyanopindolol, an antagonist atypical beta-adrenoceptors, antagonized BRL 37344-induced relaxation in a competitive fashion with a pA2 of 6.74 +/- 0.11. This pA2 value was lower than that when salbutamol was used as an agonist (p < 0.05). These results indicate that beta 3-adrenoceptors probably exist in canine bronchial smooth muscle, and that stimulation of this type of receptors produces potent bronchodilation. Therefore, a specific agonist for beta 3-adrenoceptors could be valuable in the treatment of asthma.

Acetylcholine↗

[Dyspnea and rib cage distortion in postural changes].

We studied the topographical ventilatory motion and electrical muscle activity (EMG) of intercostal muscle within the rib cage for the patients complaining dyspnea produced mostly by their postural changes. There were inappropriateness between the rib cage motion and EMG and this inappropriateness was closely related to a sensation of dyspnea. We could relieve partly dyspnea by applying the negative pressure ventilator, because of prevention of a distortion of rib cage. Based on these clinical observation, we concluded that one of mechanism to sense dyspnea was the inappropriateness between motion and electrical muscle activity within the rib cage.

Dyspnea↗

The anti-asthmatic agent KC 404 inhibits sodium absorption by canine tracheal epithelium.

To elucidate the effect of KC 404, an anti-asthmatic agent, on electrolyte transport across airway mucosa, we studied electrical properties of canine tracheal epithelium under isometric conditions in vitro. Addition of KC 404 decreased short-circuit current, transepithelial potential difference and cell conductance, accompanied by the decrease in 22Na flux from submucosa to mucosa. The KC 404-induced decrease in short-circuit current was inhibited by amiloride but not by diphenylamine-2-carboxylate. These results suggest that KC 404 selectively inhibits Na absorption by airway epithelium, thereby leading to the increase in water content in the respiratory lumen.

Absorption↗

[The acute and chronic effects of bunazosin on exercise capacity estimated by the anaerobic threshold in patients with chronic congestive heart failure].

To study the effect of bunazosin on exercise capacity in patients with congestive heart failure (NYHA II-III), anaerobic thresholds (AT, VO2, ml/min/kg) were measured before (control) and after initial 1 = 2mg administration of bunazosin (acute phase; N = 14) and after two weeks of bunazosin therapy (3mg/day, 1mg t. i. d., chronic phase; N = 6). AT were determined by Wasserman's V-slope method during ergometer exercise test with a ramp loading (10 watt/min). AT increased significantly from control during both acute (14.2 +/- 2.7 to 16.9 +/- 3.6 ml/min/kg p < 0.005) and chronic (13.6 +/- 2.5 to 16.7 +/- 1.0 p < 0.05) phase. Additionally, work (watt) attained at AT increased significantly from control during both acute (33.6 +/- 19.2 to 52.6 +/- 30.2 p < 0.005) and chronic (35.8 +/- 25 to 49.3 +/- 15 p < 0.05) phase. Pressure-rate-products (PRP, x 10(2) mmHg/min) at AT increased significantly from control during the acute phase (119 +/- 35 to 240 +/- 50 p < 0.005) alone. In the chronic phase, PRP decreased significantly at the work level equal to AT during control (from 207 +/- 41 to 187 +/- 39 p < 0.05). These data suggest that bunazosin has favorable acute and chronic effects on exercise capacity in patients with congestive heart failure.

Adult↗

[Effect of saibokuto on mucociliary transport system in the airway--basic and clinical assessments].

We studied the effects of Saibokuto, an antiasthmatic agent, on the airway mucociliary transport system. The addition of Saibokuto to a Rose chamber containing rabbit cultured tracheal epithelium dose-dependently increased ciliary beat frequency (CBF) as assessed by a photoelectric method: the maximal increase from the baseline value was 31.5 +/- 5.2% (p less than 0.001) and the concentration of Saibokuto required to produce a half-maximal effect (EC50) was 10(-4) mg/ml. This effect was not affected by the beta-adrenergic receptor antagonist propranolol or Ca(2+)-free medium, but was inhibited by the cyclooxygenase inhibitor indomethacin. Intracellular cyclic AMP levels were increased from 45.6 +/- 8.2 to 72.1 +/- 12.6 pmole/mg protein by 1.0 mg/ml Saibokuto (p less than 0.05). Thus, Saibokuto enhances ciliary motility probably through the synthesis of cyclooxygenase products and cyclic AMP. Additionally, administration of this drug to patients with chronic bronchitis, asthma and bronchiectasis improved their problems with sputum expectoration and reduced the amount of daily sputum (p less than 0.001). Therefore, Saibokuto may be of value in the treatment of patients with impaired mucociliary transport function in the airway.

Animals↗

Erythromycin inhibits Cl secretion across canine tracheal epithelial cells.

We studied the effect of the macrolide antibiotic erythromycin on bioelectrical properties of canine cultured tracheal epithelium under short-circuit conditions in vitro. Addition of erythromycin to the submucosal but not to the mucosal side dose-dependently decreased short-circuit current (Isc), the maximal decrease from the baseline value and the concentration required to produce a half-maximal effect (IC50) being 5.6 +/- 1.0 microA.cm-2 (mean +/- SE, p less than 0.001) and 18 microM, respectively. In contrast, other antibiotics including ampicillin, cephazolin and tetracycline were without effect. The erythromycin-induced decrease in Isc was not altered by amiloride, but it was abolished by bumetanide, diphenylamine-2-carboxylate2, and substitution of Cl in the bathing medium with gluconate (p less than 0.001, in each case). The effect of erythromycin on epithelial Isc was attenuated by pretreatment of cells with indomethacin but not with AA-861 a lipoxygenase inhibitor. Incubation of cells with erythromycin inhibited the release of prostaglandins E2 and F2 alpha from tracheal epithelial cells. These results indicate that erythromycin may selectively inhibit Cl secretion across airway epithelium through the inhibition of prostaglandin synthesis and suggest that this action possibly reflects its clinical efficacy in the treatment of airway hypersecretion.

Animals↗

[A case of acute isolated (Fiedler's) myocarditis diagnosed by histopathological study with rapid unfortunate course].

A 65 year-old-man was admitted to our hospital complaining of orthopnea and precordial oppressive feeling. Chest roentgenogram revealed congestive heart failure. Electrocardiogram revealed acute myocardial infarction-like pattern. Serum enzymes (CPK, GOT, LDH) were slightly elevated, but serum antiviral antibodies were not elevated. Echocardiogram showed severe symmetrical left ventricular (LV) hypertrophy, but there was no abnormality of LV wall motion. He died of progressive heart failure and ventricular fibrillation on the second hospital day. A necropsy was performed within one hour of death. The heart was enlarged (690 g) with both left and right ventricular hypertrophy. The myocardium disclosed a diffuse infiltration predominantly of eosinophilic leucocytes. Histopathological study revealed giant cell formation and granulomatous lesions in the myocardium. There was no overt endocarditis or pericarditis. We concluded that the severe LV hypertrophy was due to myocardial inflammatory swelling. From these findings, we diagnosed this case as acute isolated (Fielder's) myocarditis.

Acute Disease↗

[An infantile case of cerebral infarction associated with thrombocytosis].

Cerebral infarction in children is often caused by intracranial vascular disorder, cardiac disease, head injury, or infection, and is rarely induced by blood disease. In this paper, we describe an infantile case of cerebral infarction associated with thrombocytosis. A female infant of eight months of age developed left hemiparesis after a slight head injury. Her CT and MRI demonstrated a cerebral infarction located from the right internal capsule to the right corona radiata. Laboratory findings revealed iron-deficiency anemia and thrombocytosis with a platelet count 107.5 x 10(4)/mm3. Although she had no disorder that had caused iron deficiency, serum Fe value of the patient was low with a count of 18 micrograms/dl. Her bone marrow was normal except for a slight increase in the number of megakaryocytes. One month later, her anemia was improved by means of oral iron replacement. However, her platelet count remained at more than 100 x 10(4)/mm3 as it had been before. Her condition of left-sided hemiparesis gradually improved by a program of rehabilitation, and did not recur after aspirin administration. Although the main cause of her thrombocytosis that led to a transient cerebrovascular accident is obscure, it is postulated that her iron deficiency anemia induced secondary thrombocytosis, or else the patient had essential thrombocytosis.

Anemia, Hypochromic↗

[Differentiation therapy of acute promyelocytic leukemia: two successful cases of remission induction by all-trans retinoic acid].

We described two pediatric patients with acute promyelocytic leukemia (APL) who were successfully induced into complete remission with all-trans retinoic acid (ATRA, 45 mg/m2 per day) after failing on conventional chemotherapy. Initial response was observed as correction of DIC within a week of treatment. Hematologically, initial increase of maturing leukocytes reached a peak peripheral WBC count on the 16th and 20th day, respectively. However, these seemingly differentiated leukocytes retained Auer body and dysplastic features and there was no concomitant recovery of erythroid and megakaryocytic lineages at this point. A sudden drop of leukocyte counts after this peak made a brief period of leukopenia before the complete remission was finally attained morphologically in 4-5 weeks. Thus, remission of APL by ATRA therapy consisted of a two-phase course. In one patient, we observed an increase of histiocytes phagocytizing leukocytes in the marrow during the recovery from leukopenia. It is, therefore, postulated that the two-phase course of recovery may reflect the differentiation of leukemic cells by ATRA and subsequent clearance of senescent cells by the reticuloendothelial system followed by regeneration and differentiation of residual normal hematopoietic stem cells.

Adolescent↗

A soluble factor induced by an extract from Pinus parviflora Sieb et Zucc can inhibit the replication of human immunodeficiency virus in vitro.

We showed that an extract (PC6) from cones of Pinus parviflora Sieb et Zucc induced the human T-cell line CEM to produce a pepsin-sensitive soluble factor(s) that could inhibit the replication of the type 1 human immunodeficiency virus (HIV-1) in CEM T cells, in U-937 histocytes, in THP-1 monocytes, and in mitogen-activated human tonsillar mononuclear cells. Indirect immunofluorescence staining and polymerase chain reaction analysis of the PC6-induced CEM cells revealed the absence of known lymphokines/cytokines except granulocyte/macrophage colony-stimulating factor (GM-CSF), interleukin 3 (IL-3), transforming growth factor beta 1 (TGF-beta 1), and tumor necrosis factor alpha (TNF-alpha). However, functional studies with recombinant IL-3, TNF-alpha, and TGF-beta 1 showed that these three factors did not inhibit HIV-1 replication in CEM cells. Neutralization of the PC6-induced HIV-1-inhibiting factor(s) with commercially available neutralizing antibodies to GM-CSF and TNF-alpha also did not abrogate the anti-HIV-1 impact. Thus, the anti-HIV-1 factor induced by PC6 may be novel. Molecular sieve separation showed that the anti-HIV-1 factor(s) is smaller than 30 kDa. Affinity chromatography using a DEAE-cellulose column enriched the factor that inhibited HIV-1.

Antineoplastic Agents↗