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Biomedical subjects

K Kudo

Publications and source records attributed to K Kudo.

At least 235 records · Page 13Linked to original sources
PubMed1992

Erythromycin inhibition of lipopolysaccharide-stimulated tumor necrosis factor alpha production by human monocytes in vitro.

The mechanism of clinical effectiveness of low-dose and long-term erythromycin (EM) treatment for diffuse panbronchiolitis, sinobronchial syndrome, and associated otitis media with effusion was investigated by studying the effects of EM on tumor necrosis factor alpha (TNF-alpha) production by cultured human monocytes stimulated with lipopolysaccharide. At concentrations of 0.1 microgram/mL or more, EM inhibited TNF-alpha release from human monocytes stimulated by lipopolysaccharide in a dose-dependent manner. Of the other macrolides tested, roxithromycin, an EM derivative, also showed significant inhibition of TNF-alpha production, whereas josamycin failed to inhibit TNF-alpha release from monocytes. Nonmacrolidic drugs such as minocycline hydrochloride, ofloxacin, or penicillin G had no significant effect on TNF-alpha production. These results suggest that the clinical improvement of chronic respiratory diseases by EM may depend on the suppression of production of inflammatory cytokines such as TNF-alpha.

Anti-Bacterial Agents↗
PubMed1992

Functions of ascending thin limb of Henle's loop with special emphasis on mechanism of NaCl transport.

Major controversy concerning the ascending thin limb of Henle's loop (ATL) centers on the urine concentration mechanism based on the countercurrent multiplier system in the inner medulla of the kidney. This renal tubular segment has specific transport properties which function to dilute the urine without any movement of water across the epithelium. This segment is fundamentally impermeable to water, moderately permeable to urea, and highly permeable to Na+ and Cl-. Whether NaCl is reabsorbed actively in the ATL has long been an important question. While mathematical modelling studies have failed to explain completely how the osmotic gradient in the inner medulla is generated without active NaCl transport in the ATL, the experimental data support the view that active NaCl reabsorption is absent. Recently, we succeeded in measuring the intracellular Na+ concentration by using the fluorescent Na+ indicator sodium-binding benzofuran isophthalate in the in vitro microperfused ATL. Our data suggest that the ATL maintains a low intracellular Na+ concentration by the ouabain-sensitive Na+/K+ ATPase in the basolateral membrane, and that the luminal membrane of the ATL has furosemide-insensitive Na+ permeability. Active Na+ reabsorption estimated in our study amounts to only a few per cents of the net Na+ reabsorption in the ATL. It is therefore suggested that the major role of Na+ extrusion in the ATL cells is to maintain a low cellular Na+ concentration against ambient hyperosmolarity, although small but substantial amount of Na+ is reabsorbed by the furosemide-insensitive Na+ permeability and ouabain-sensitive Na+/K+ ATPase.

Animals↗
PubMed1992

Primary mediastinal diffuse large cell lymphoma initially presented with pericardial infiltration.

A 33-year-old Japanese woman visited our hospital with progressive dyspnea. A chest roentgenogram and a chest computed tomogram revealed a mediastinal tumor and pericardial effusion. Ultrasound cardiography revealed the existence of cardiac tamponade. She was successfully treated with emergency pericardial drainage, thoracocentesis and chemotherapy. The histological diagnosis of diffuse large B cell lymphoma was established with the tumor specimen obtained by transcutaneous fine needle aspiration biopsy and through immunohistochemical analysis. This is a rare case of primary mediastinal diffuse large cell lymphoma with initial presentation of a symptom related to pericardial effusion.

Adult↗
PubMed1992

Retrospective evaluation of surgical intervention following chemo- and radiotherapy of maxillary sinus cancers.

During the past 15 years, 30 patients with squamous cell carcinomas of the maxillary sinus were treated by modified partial maxillectomy following chemo- and radiotherapy, taking care to preserve facial contour and function as far as possible. Follow-up evaluation showed that local recurrences, and regional lymph node and distant metastases were more frequent in T4 patients than in T3 patients. Evaluation of the histopathological effects of preoperative chemo- and radiotherapy at the time of surgery showed that T4 patients tended to have a poorer response to the treatment than T3 patients. Analysis according to the direction of primary tumor extension showed that the incidence of local recurrence was higher in the superolateral type, whereas that of regional lymph node metastasis was higher in the medial type. The cumulative 5-year survival was high (72.2%) in Stage III patients and low (22.5%) in Stage IV patients. The overall rate was 55.4%. The treatment produced relatively good outcomes in T3 patients but poor outcomes in T4 patients. These findings indicate that T4 carcinoma of the maxillary sinus must be managed initially by a combination of irradiation and multi-chemotherapeutic drugs, and then treated by more extensive surgical resection.

Adult↗
PubMed1992

[Assessment and management of acute severe asthma].

In the management of acute severe asthma it is very important to start the treatment as soon as possible, by appropriate evaluation of the physical status and signs of airflow obstruction. We propose a guideline to be used by patients with asthma, emergency car crews, physicians and nurses to evaluate the severity and to choose the appropriate management of acute asthma, including intubation and mechanical ventilation, by the assessment of clinical features, as well as blood gas analysis and pulmonary function test. Several researchers have demonstrated that the additional administration of aminophylline to inhaled or subcutaneous beta 2-agonist bronchodilator during the first 4 hours of an attack provides no additional benefit compared to the administration of beta 2-agonist alone. In our retrospective study of 68 episodes of acute severe asthma in the last 5 years at our institute, however, the additional administration of aminophylline with beta 2-agonists was clearly shown to be effective with infrequent minor side effects.

Acute Disease↗
PubMed1992

Postmortem changes of triazolam concentrations in body tissues.

Postmortem changes of triazolam concentrations in body tissues were examined using rats, in order to find the most suitable tissue samples for toxicological analysis. Triazolam was orally given to rats (5 mg/kg), and then the rats were sacrificed 1 hour after administration. Tissue samples were collected 0, 1 and 2 days after storage at 22-24 degrees C, and the triazolam concentration in each sample was measured using gas chromatography with a nitrogen phosphorus detector. Triazolam concentrations were markedly increased in the spleen, the abdominal muscle, the liver and the kidney, and were slightly increased in the blood and the lung. On the other hand, no changes were observed in the thigh muscle or the brain, and the value in the thigh muscle was similar to those in the blood samples collected immediately after death. The results indicate that triazolam diffuses into the surrounding tissues through the stomach wall after death, so that the thigh muscle and the brain have to be analyzed as well as the blood for a correct diagnosis of triazolam ingestion.

Administration, Oral↗
PubMed1992

[A case of gastric carcinoma with peritonitis carcinomatosa responding remarkably to etoposide, adriamycin and cisplatin (EAP) therapy].

The patient was a 62-year-old male who had Borrmann 4 type gastric cancer. He presented massive ascites due to peritonitis carcinomatosa and the cytology of ascites was class V. He was treated with 3 courses of EAP (etoposide, adriamycin, cisplatin) therapy. Computed tomography showed ascites nearly disappeared. Remarkable improvement was observed by barium meal study and endoscopic examination, and partial remission (PR) was achieved. As for toxicity bone marrow suppression, alopecia and elevation of BUN were observed.

Adenocarcinoma↗
PubMed1992

[Inhibitory effect of vitamin E on rats with bladder tumors induced by N-butyl-N-(4-hydroxybutyl) nitrosamine].

The anticancer activity of vitamin E may involve its functions as an antioxidant free radical scavenger, and immunomodulater. We studied the effect of vitamin E on rats with bladder tumors induced by N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN). Three-week-old male Wistar rats were given a diet containing 0 (A), 2 mg (B:control), 40 mg (C), and 60 mg (D) of vitamin E per 100 g of food, respectively, until they were 30 weeks old. The carcinogen, 0.05% BBN was given in drinking water to the rats for 8 weeks from the 9th week of age, and all rats were killed at 30 weeks old. The number and the size of the tumors, the thickness of epithelial cell layers in hyperplasia, the diameter of papillary tumor, and the cellular atypia were assessed by using a point method according to U-test. As assessment of immune response, the lymphocyte count in blood, the degree of lymphocyte infiltration in tissue, and CD4 (helper/inducer-T cell)/CD8 (suppressor/cytotoxic-T cell) ratio in blood by flow cytometry using monoclonal antibodies were evaluated according to the t-test. Moreover, the correlation between CD4/CD8, cellular atypia, and serum level of vitamin E were evaluated by coefficient of correlation. There were no differences between any two groups in the number or the size of the tumors. The cellularity in group A was significantly higher than that in group D (p less than 0.05). The point of the cellular atypia tended to decrease, with increasing dose of vitamin E, but not significantly, whereas the CD4/CD8 tended to increase by increasing the dose of vitamin E.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Determination of polysulphides in blood by gas chromatography and gas chromatography-mass spectrometry.

A sensitive and simple method to determine polysulphides in human blood, using an extractive alkylation technique and gas chromatography, has been devised. Polysulphides were alkylated with pentafluorobenzyl bromide, and then converted into bis(pentafluorobenzyl)disulphide by desulphuration with potassium cyanide. The disulphide was analysed qualitatively by mass fragmentography and quantitatively by gas chromatography with electron-capture detection. The lower limit of detection was 0.005 mumol/ml. Field testing in a suicide case confirmed the validity of the method.

Alkylation↗
PubMed1991

Determination of kerosene and light oil components in blood.

A sensitive and rapid method to analyse fuel components in blood from rats exposed to kerosene or light oil vapour was developed by making use of capillary gas chromatography/mass spectrometry. The aliphatic hydrocarbons with carbon numbers 8-10 and aromatics such as toluene, xylene, 3- and 4-ethyltoluene and trimethylbenzenes were clearly detected in blood from rats exposed to kerosene or light oil vapour, using the head-space method combined with the salting-out technique. The concentration ratio of pseudocumene to toluene in blood exposed to light oil was higher than that in the case of exposure to kerosene. The lower limits of detection were 50 pg and 1 ng in toluene and pseudocumene, respectively. Our suggestion is that this method is useful in forensic investigations to detect fuel components in blood and for the purposes of differentiating kerosene and light oil in blood tissues.

Animals↗
PubMed1991

Forensic analysis of triazolam in human tissues using capillary gas chromatography.

A reliable and sensitive method has been developed to assess the concentrations of the hypnotic drug triazolam in human tissues, including putrefied tissues. The method involves a 3-step solvent extraction, clean-up on a silica gel column and gas chromatography using a nitrogen phosphorus detector and a capillary column. Estazolam was used as an internal standard. The calibration curve was linear over the concentration range 1 ng/g-1 microgram/g and the lower limit of detection was 0.5 ng/g. A forensic study was performed on the toxicological effects of triazolam using putrefied tissues.

Adult↗
PubMed1991

Chronic synergistic effect of endothelin-1 and angiotensin II on blood pressure in conscious rats.

We assessed whether there is an interaction between angiotensin II (Ang II) and endothelin-1 (ET-1) in the regulation of blood pressure and sodium and water metabolism in rats. Male Sprague-Dawley rats were divided into four groups. Group I rats received Ang II at a subpressor dose (400 micrograms/kg/day i.p.) for up to 6 days. Group II rats received ET-1 at a subpressor dose (3 micrograms/kg/day i.v.) for up to 6 days. Group III rats received both the subpressor dose of Ang II and the subpressor dose of ET-1. Group IV rats received vehicle only. There was no significant difference in systolic blood pressure (SBP) among groups I, II, and IV during the study. On day 6, SBP in groups I, II, and IV was 148.0 +/- 3.0, 142.7 +/- 2.9, and 143.5 +/- 3.0 mm Hg, respectively. On the other hand, SBP in group III was higher than those of the other groups on day 2 and remained elevated thereafter. On day 6, SBP in group III rats was 189.0 +/- 12.5 mm Hg. There were no significant differences in body weight, fluid intake, urine volume, urinary sodium excretion, or urinary potassium excretion among the four groups. The present results suggest that Ang II and ET-1 exert their pressor effects synergistically and might play a role in controlling blood pressure. They also suggest the possibility of the existence of a common pathway in the hypertension-producing mechanism of these two peptides.

Angiotensin II↗
PubMed1991

Evidence for presence of functional beta-adrenoceptor in rabbit S2 proximal straight tubules.

The effect of isoproterenol on the electrophysiological properties of the S2 proximal segment of the rabbit was examined. Isoproterenol at 10(-8) to 10(-4) M depolarized the basolateral membrane voltage (Vb) in a dose-dependent manner. Propranolol attenuated the isoproterenol-induced depolarization. These possible mechanisms of cell depolarization were explored. The role of luminal Na(+)-organic solute cotransport was negligible, since the removal of organic solute did not change the depolarization. Basolateral Na(+)-(HCO3-) cotransport was supported by the finding that 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid inhibited isoproterenol-induced depolarization. Basolateral K+ conductance was suggested by the finding that the application of Ba2+ blocked the isoproterenol-induced depolarization. Na(+)-K(+)-adenosine-triphosphatase (ATPase) was questionable. Although ouabain blocked isoproterenol-induced depolarization, the removal of Na+ did not inhibit the depolarization. Further experiment revealed that dibutylyl-adenosine 3',5'-cyclic monophosphate (cAMP), 8-bromo cAMP, and forskolin did not mimic the response of isoproterenol. These results demonstrate: 1) there is a functional beta-adrenoceptor that depolarizes Vb; 2) isoproterenol-induced depolarization is due to an inhibition of basolateral K+ channel or the activation of basolateral Na(+)-(HCO3-)n cotransport; 3) isoproteronol-induced depolarization is independent of cAMP in the rabbit proximal tubule.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗
PubMed1991

[Effect of XKJ-001, a crude drug preparation, on body water distribution and water excretion in mice].

The effect of XKJ-001, a crude drug preparation based on Seisho-ekki-to, was investigated on the hematocrit, plasma volume, extracellular and interstitial fluid volumes as well as water excretion in mice. Mice were housed in an animal room maintained at 34 degrees C for 3 d with water and food freely available. While the hematocrit, extracellular and interstitial fluid volumes increased, the plasma volume decreased. These results suggest that the distribution of body water in mice housed at high environmental temperature exhibit the state of water metabolism disorders (Suitai) described in Kampo medicine. After the administration of XKJ-001 (3 g/kg, once a day) for 5 d, mice were housed in an animal room maintained at 34 degrees C for 3 d. The administration of XKJ-001 was allowed to continue on the day 0, day 1 and day 2. XKJ-001 inhibited the increase in hematocrit and the changes in body water distribution of mice induced by high environmental temperature. An effect of XKJ-001 on water excretion in mice was investigated in comparison with hydrochlorothiazide (HTZ). Distilled water (D.W., 100 ml/kg) or bicarbonate saline (B.S., 100 ml/kg) was intraperitoneally injected immediately after the oral administration of XKJ-001 (1.5 g/kg) or HTZ (15 mg/kg). The water excretion was enhanced after 3 h for XKJ-001 and after 6 h for HTZ after the intraperitoneal injection of D.W. As for the intraperitoneal injection of BS, HTZ enhanced the water excretion, however, XKJ-001 exhibited no effect. These results suggest that XKJ-001 has activities on water maldistribution and facilitates the water excretion.

Animals↗