Search PubMed⌕ Search

Biomedical subjects

K Kudo

Publications and source records attributed to K Kudo.

At least 289 records · Page 16Linked to original sources
PubMed1989

Acute and chronic effects of synthetic atrial natriuretic factor on blood pressure and sodium excretion in spontaneously hypertensive rats.

To assess possible roles of atrial natriuretic factor (ANF) in the regulation of blood pressure in spontaneously hypertensive rats (SHR), we performed two series of experiments. First, we studied acute hypotensive, natriuretic and diuretic effects of ANF in pentobarbital-anesthetized SHR and age-matched Wistar-Kyoto rats (WKY). A synthetic ANF of 25 amino acid residues was intravenously administered as a bolus at doses of 0.1, 1.0, 2.5 and 5.0 micrograms/kg. In SHR group, a significant decrease in mean arterial pressure (MAP) was observed at a dose of 1.0 micrograms/kg, and the decrease was dose-dependent. On the other hand, in WKY group, the hypotensive effect of ANF was not observed until a dose of 5.0 micrograms/kg. The diuretic and natriuretic effects of ANF were observed at a dose of 2.5 micrograms/kg in SHR and 5.0 micrograms/kg in WKY, respectively. Second, we also studied chronic effect of ANF on the development of hypertension in 6-week-old SHR. The SHRs, on regular diet or given 1% NaCl solution for drinking, were continuously infused into the jugular vein by osmotic minipumps with ANF (15, 75 and 150 micrograms/kg/day) or vehicle (physiological saline) as controls for up to 14 days. ANF at a dose of 150 micrograms/kg/day attenuated transiently the development of hypertension in the sodium-loaded SHR. However, the blood pressure returned to control levels by day 5. ANF at doses of 15 and 75 micrograms/kg/day did not affect the development of hypertension. In SHR on regular diet, ANF at a dose of 150 micrograms/kg/day did not affect the development of hypertension. In addition, ANF did not induce any significant changes in urine volume, fluid intake, and urinary excretion of sodium and potassium in SHR, whether they were sodium-loaded or not, when compared to those in vehicle-infused SHR. These results indicate that there may be a significant difference in the sensitivity to diuretic, natriuretic and hypotensive actions of ANF between SHR and WKY. Moreover, it is suggested that ANF may play significant roles by its vascular effect at the early stage of development of hypertension in sodium-loaded SHR.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Blood pressure and renal responses to synthetic rat atrial natriuretic factor in deoxycorticosterone acetate-salt hypertension.

To assess possible roles of atrial natriuretic factor (ANF) in the regulation of blood pressure in deoxycorticosterone acetate (DOCA)-salt hypertensive rats, we performed two series of experiments. First, we studied acute hypotensive, and natriuretic and diuretic effects of ANF in pentobarbital-anesthetized DOCA-salt hypertensive rats and age-matched controls. A synthetic rat ANF was intravenously administered as a bolus at doses of 0.5, 2.5 and 5.0 micrograms/kg. In DOCA-salt rats, a significant decrease in mean arterial pressure was observed at a dose of 5.0 micrograms/kg, whereas at a dose of 2.5 micrograms/kg in control rats. On the other hand, the diuretic and natriuretic effects of ANF were observed at a dose of 2.5 micrograms/kg in DOCA-salt rats and 5.0 micrograms/kg in control rats. Second, we examined chronic effect of ANF on the development of hypertension in DOCA-salt rats. The DOCA-salt rats, given 1% NaCl solution for drinking, were continuously infused with ANF (15, 75 and 150 micrograms/kg/day) or vehicle (physiological saline) into the jugular vein by osmotic minipumps for up to 14 days. In DOCA-salt treated rats, ANF at doses of 75 and 150 micrograms/kg/day attenuated significantly the development of hypertension, although at a dose of 15 micrograms/kg/day did not. The hypotensive effect of ANF was sustained throughout the experimental period and the effect of ANF at a dose of 150 micrograms/kg/day was more prominent than that of this peptide at a dose of 75 micrograms/kg/day. ANF did not induce any significant changes in urine volume, fluid intake and urinary excretion of sodium and potassium in DOCA-salt rats when compared to those in vehicle-infused DOCA-salt rats. These results indicate that DOCA-salt rats are more sensitive to ANF in diuretic and natriuretic effects, and less sensitive to ANF in hypotensive effect compared to control rats. Moreover, it is suggested that ANF can affect the regulation of blood pressure by its vascular effect in the development of hypertension in DOCA-salt rats.

Animals↗
PubMed1989

Effects of antihypertensive drugs on renal function and atrial natriuretic polypeptide in spontaneously hypertensive rats with renal ablation.

To determine whether pharmacological control of blood pressure could affect the renal function and levels of atrial natriuretic polypeptide (ANP) in spontaneously hypertensive rats (SHR) with renal ablation, and to ascertain the benefits of antihypertensive drugs, we studied effects of oral administration of captopril (50 mg/kg/day), an inhibitor of angiotensin converting enzyme, benidipine (3 mg/kg/day) and nilvadipine (10 mg/kg/day), newly developed blockers of calcium channel, and indapamide (10 mg/kg/day) for 14 days on systolic blood pressure, serum creatinine, blood urea nitrogen, and plasma ANP concentration in SHR subjected to surgical removal of the left kidney and infarction of two-thirds of the right kidney (5/6 nephrectomy) a week before. Three weeks after the surgery, systolic blood pressure (mmHg) in the untreated group was 253 +/- 9 (n = 10), in the captopril group 156 +/- 9 (n = 7, p less than 0.05), in the benidipine group 197 +/- 9 (n = 7, p less than 0.05), in the nilvadipine group 146 +/- 9 (n = 7, p less than 0.05) and in the indapamide group 206 +/- 5 (n = 7, p less than 0.05). Serum creatinine (mg/100 ml) was lower in the captopril group (0.58 +/- 0.02, n = 7, p less than 0.05) and in the benidipine group (0.50 +/- 0.03, n = 7, p less than 0.05) but not in the nilvadipine group and in the indapamide group 3 weeks after 5/6 nephrectomy compared to the untreated group. Blood urea nitrogen was also lower in the captopril group and in the benidipine group but not in the nilvadipine group and in the indapamide group. Plasma ANP concentration was significantly reduced by the treatment with captopril and benidipine but not with nilvadipine and indapamide. These results suggest that the reduction of blood pressure by the inhibition of angiotensin converting enzyme with captopril has the potential to ameliorate renal function of the SHR with remnant kidney, a model of chronic renal failure with hypertension, associated with the decreased concentration of plasma ANP. However, it remains to be determined whether the reduction of blood pressure by calcium channel blockers may be involved in the delayed progression of renal failure in this model since there were disparate effects on renal function and plasma ANP concentration with these two calcium channel blockers.

Animals↗
PubMed1989

On-line plasma exchange for sepsis in neonates and infants.

The present study was designed to assess the effectiveness of on-line plasma exchange (on-line P.E.) between septic infants and healthy adults using septic puppies. The plasma separation system consisted of a membrane plasma separator and a plasma treatment system, KM-9027 (Kurarey Co.) equipped with small 2 channel blood and plasma pumps. 5 X 10(9) CFU/ml/kg of E. coli with endotoxin was injected intravenously into 22 puppies and they were divided into 4 groups, namely untreated group (n = 7), on-line P.E. group (n = 5), P.E. group (n = 5), sham group (n = 5). In the on-line P.E. group, about 80 ml/kg of plasma in septic puppy was replaced during 2 hr with fresh plasma simultaneously obtained from healthy adult dog. As the results, 4 of 5 survived in the on-line P.E. group and 1 of 5 survived in the P.E. group, while all other puppies died within 24 hr. In the P.E. group and on-line P.E. group, mean blood pressure and urinary output were significantly improved (p less than 0.05) by the treatment. The numbers of E. coli and endotoxin concentration in the blood were reduced significantly (p less than 0.05) only in the treatment with on-line P.E. opsonic activity recovered significantly (p less than 0.05) in P.E. group. This system appears to be effective and applicable for sepsis in infants and neonates.

Age Factors↗
PubMed1989

Surgical correction and osteoplasty for forward dislocation of temporomandibular joint.

Surgical correction and osteoplasty were carried out in one case of prolonged and three cases of recurrent forward dislocation of the temporomandibular joint, two of the patients in the latter cases having mental disorders and one having a cerebral lesion. A hockey-stick-shaped preauricular incision was made, ending in the hair-bearing part of the temple. Then, the temporal fascia and muscle were divided anteriorly from the temporal bone. In two aged patients, a fragment of the zygomatic arch was pushed out and down, joining under the articular tubercle. In two younger patients, the cortical bone of the mandible was separated by sagittal split-ramus osteotomy for mandibular prognathism, and two graft blocks removed from the iliac bone were implanted between the root of the posterior zygomatic arch and the anterior cut-edge of the articular tubercle. In 3 of the 4 patients, the fragments or grafts were fixed by means of ligation using wire so as to make contact with the root of the posterior zygomatic arch. There was no recurrence of dislocation during a period of 2-5 years after surgery.

Adult↗
PubMed1989

Inhibitory effect of cicletanine on vascular smooth muscle cell proliferation.

We investigated the effect of cicletanine on vascular smooth muscle cell proliferation. In cultured vascular smooth muscle cells from rat mesenteric artery, cicletanine (10(-5) to 10(-4) M) increased prostacyclin synthesis (measured as 6-keto-PGF1 alpha by radioimmunoassay) dose-dependently. When added to cells in which mitogenesis was activated by 10% fetal bovine serum, cicletanine (3.3 x 10(-5) to 10(-4) M) inhibited [3H] thymidine incorporation up to 31% of the control level. Inhibitory effect of cicletanine on mitogenesis was also confirmed at 48 h by cell counts (control: 18965 +/- 629, cicletanine 10(-4) M: 14840 +/- 430, n = 6). The effect of cicletanine on platelet-derived growth factor (PDGF)-stimulated [3H] thymidine incorporation was not abolished by prostaglandin synthesis inhibition with aspirin, but the prostacyclin analogue OP-41483 (125-1000 ng/ml) inhibited it dose-dependently. Calcium entry blockers, nifedipine (3.3 x 10(-6) M) and diltiazem (10(-4) M), inhibited both [3H] thymidine incorporation and cell proliferation, while furosemide did not affect it. Cicletanine also inhibited PDGF-stimulated [3H] thymidine incorporation in cultured glomerular mesangial cells. We conclude that cicletanine stimulates prostacyclin synthesis and inhibits cell proliferation in cultured vascular smooth muscle cells, which may possibly be related to the intracellular calcium mobilization. Such a property might be contributory to the antihypertensive activity of cicletanine.

Animals↗
PubMed1989

Lymphokine activity production in graft-versus-host reactions across minor histocompatibility antigen barriers.

Activated T cells responding to murine minor histocompatibility antigens (HA) were characterized according to the patterns of lymphokine activity production. Although B10.D2/nSN and BALB/c are mutually non-reactive in mixed lymphocyte reaction (MLR), graft-versus-host reaction (GVHR) can be induced by the injection of a large amount of B10.D2/nSN lymphoid cells into irradiated BALB/c recipient mice. Spleen cells from such GVHR mice spontaneously produced interleukin 3 (IL-3)-dependent cell-stimulating activity in cultures, but did not produce interleukin 2 (IL-2). Normal B10.D2/nSN spleen cells also produced IL-3-like activity, but not IL-2 in MLR supernatants, in response to irradiated BALB/c splenocytes. In addition, B-cell stimulatory factor-1 (BSF-1)/interleukin 4 (IL-4) and colony-stimulating factor (CSF) activity were detected in MLR supernatants. The properties of the produced lymphokine activities were similar to those produced in syngeneic transplant mice and syngeneic MLR, but a difference in the time course of lymphokine production existed between GVHR and syngeneic transplant mice. These results indicate that T cells may be activated in vivo in allogeneic transplantation when the donor and the recipient are matched for major HA, and are non-reactive in MLR. Also, the character of lymphokine-producing T cells activated by minor HA may not be qualitatively different from those responding to irradiated syngeneic cells.

Animals↗
PubMed1989

[Treatment of endotoxin shock due to gram-negative bacteremia using extracorporeal circulation].

The effectiveness and significance of the various therapeutic methods of extracorporeal circulation were assessed in an experimental model of septic endotoxin shock. After sepsis was produced in 30 puppies by intravenously injecting 5 X 10(9) CFU/ml/kg of E. coli, on-line plasma exchange, conventional plasma exchange, charcoal plasma perfusion, hemofiltration, and sham perfusion were performed for 2 hr. As a result, 4 of the 5 puppies in the on-line plasma exchange group and one of the 5 in the conventional plasma exchange group survived; the others all died. In the on-line plasma exchange group, the number of E. coli decreased to 2.5 X 10 CFU/ml at the end of the treatment, while it was 1.3 X 10(3) CFU/ml in the sham perfusion group. The endotoxin concentration was also reduced significantly, while plasma opsonin activity was remarkably elevated. These results suggest the significance of achieving the elimination of endotoxin in blood and an increase in plasma opsonin activity simultaneously in the treatment of septic endotoxin shock.

Animals↗
PubMed1989

[Airway responsiveness measured by body plethysmograph connecting a circuit of an inhalation system of serially concentrated bronchoconstrictant].

We developed a new methodology to examine the bronchial response to the bronchoconstrictants, acetylcholine and methacholine. An inhalation device was connected to the body plethysmograph circuit so that a minute inhalation of serially concentrated bronchoconstrictant could be quickly switched to the circuit of the measurement of the airway resistance. The following were calculated: airway responsiveness in terms of sensitivity, provocative dose to increase the airway resistance up to 35% from the baseline. PC35 or PD35 and the reactivity, the slope of the declining specific airway conductance and %delta SGaw. The airway responsiveness was examined in asthmatics, COPD outgrew -childhood asthma patients and normal subjects. These three groups were categorised differently from each other in both sensitivity and reactivity.

Acetylcholine↗
PubMed1989

Inhibitors of sterol synthesis. Chromatography of acetate derivatives of oxygenated sterols.

The separation of the acetate derivatives of a number of oxygenated sterols was achieved by medium pressure liquid chromatography on silica gel columns and by normal and reversed phase high performance liquid chromatography. We have explored the application of these chromatographic systems for the analysis of oxygenated sterols of plasma samples from two normal human subjects. The addition of highly purified [14C]cholesterol to plasma permitted the detection and quantitation of oxygenated sterols formed by autoxidation of cholesterol during processing of the samples. Special attempts to suppress autoxidation of cholesterol included the use of an all-glass closed system for saponification and extraction under argon followed by rapid removal of cholesterol from the polar sterols by reversed phase medium pressure liquid chromatography. Chromatographic analyses of the [3H]acetate derivatives of the polar sterols provided a sensitive approach for the detection and quantitation of the individual oxygenated sterols. Oxygenated sterols detected in plasma included cholest-5-ene-3 beta,26-diol, (24S)-cholest-5-ene-3 beta,24-diol, and cholest-5-ene-3 beta,7 alpha-diol. After correction for their formation by autoxidation of cholesterol during processing of the samples, very little or none of the following sterols were observed: cholest-5-ene-3 beta,7 beta-diol, 5 alpha,6 alpha-epoxy-cholestan-3 beta-ol, 5 beta,6 beta-epoxy-cholestan-3 beta-ol, and cholestane- 3 beta, 5 alpha,6 beta-triol, and the 25-hydroxy, 22R-hydroxy, 21-hydroxy, 20 alpha-hydroxy, and 19-hydroxy derivatives of cholesterol.

Acetic Anhydrides↗
PubMed1989

[Clinical study of prostatic cancer].

Eighty patients with prostatic cancer, who first visited Kyorin University School of Medicine from January 1976 through December 1986, were analyzed. Incidence of prostatic cancer was 3.9% among male inpatients. Age distribution was between 55 and 88, with an average of 72 years old. The most common symptoms were dysuria followed by pollakisuria, hematuria, lumbago and lower extremity pain. Duration from onset of symptom to examination ranged from 6 to 84 months, with an average of 22 months. Clinical stage was A in 7.5%, B in 10%, C in 11.3% and D in 71.3%. According to histological grade, well, moderately, and poorly differentiated adenocarcinomas were observed in 29.9, 29.9 and 40.2%, respectively. According to the General Rules for Clinical and Pathological Studies on Prostatic Cancer, clinical T classification were T0 in 8.7%, T1 in 3.8%, T2 in 47.5%, T3 in 27.5% and T4 in 12.5%. In the correlation between stage and grade, the largest number of poorly differentiated adenocarcinoma cases was in stage D. There was no correlation between stage and T classification. Of the 80 patients, 71.25% were treated with antiandrogen therapy, 16.25% with radiation therapy chiefly, 7.5% by surgery chiefly, and 5% with chemotherapy. Survival rate was calculated by the Kaplan-Meier method. Overall survival rate of the 80 patients was 54.4% at 5 years. Survival rate by stage were 100% in stage A at 4 years, and 100% in B, 87.5% in C and 40.5% in D at 5 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1988

Sensitive determination of diazepam and N-desmethyldiazepam in human material using capillary gas chromatography-mass spectrometry.

A reliable and sensitive capillary gas chromatographic-mass spectrometric method was developed for the detection and determination of diazepam and its major metabolite, N-desmethyldiazepam, in human material. Medazepam served as the internal standard. Quantitative determination was achieved using mass fragmentography with selected ions of m/z 256 for diazepam and m/z 242 for N-desmethyldiazepam and medazepam. The limit of detection was 1 ng/g and the recoveries were 98.54 +/- 3.95% for diazepam and 98.66 +/- 6.48% for N-desmethyldiazepam. The calibration graph was linear over the concentration range from 1.0 ng/g to 1.0 microgram/g for diazepam and N-desmethyldiazepam. Using this method, trace amounts of diazepam and N-desmethyldiazepam were detected in the tissues of an autopsied individual.

Aged↗
PubMed1988

Evidence that a substance P-like peptide mediates the non-cholinergic excitatory response of the carp intestinal bulb (Cyprinus carpio).

The participation of substance P in the noncholinergic contraction induced by transmural stimulation (TMS) of the carp intestinal bulb was examined. In the presence of atropine, substance P caused the contraction of carp intestinal bulb smooth muscle in a concentration dependent manner (1 nmol/l - 1 mumol/l). The EC50 value was 28 +/- 7 nmol/l (n = 6). Substance P-induced desensitization (1 mumol/l for 15 min), decreased the response to substance P and the atropine-resistant contraction induced by TMS (20 Hz) selectively. In contrast, in the absence of atropine, the contraction induced by TMS (20 Hz) was slightly attenuated with the substance P-induced desensitization. The acid extract obtained from the carp intestinal bulb contained a smooth muscle excitatory material whose pharmacological properties were consistent with those of substance P. The present results indicate that a substance P-like peptide is present in the carp intestinal bulb which is involved in the non-cholinergic contraction induced by TMS.

Acetylcholine↗
PubMed1988

A case report of destructive mole after uterine rupture.

We describe a patient 17 weeks pregnant whose complaints were diagnosed as acute abdomen. The patient underwent a total abdominal hysterectomy and uterine rupture was found with, surprisingly, a live fetus. Pathologic examination indicated destructive mole.

Adult↗
PubMed1988

Toxicological analysis of thiamylal in biological materials by gas chromatography/mass spectrometry.

A reliable and sensitive method to analyze thiamylal in biological materials was developed, using gas chromatography/mass spectrometry (GC/MS). A quantitative determination was made by use of mass fragmentography with the lower detection limit of 0.01 microgram/g. Thiopental was used as the internal standard. Distribution of the drug in the blood and body tissues of rats was examined. The method was then used to detect thiamylal in tissues from an autopsied patient and concentration of this drug in the body materials was evaluated, from medico-legal aspects.

Adipose Tissue↗
PubMed1988

Role of thromboxane A2 in the hypotensive effect of captopril in essential hypertension.

We have previously reported that captopril stimulates thromboxane A2 synthesis in patients with essential hypertension. In the present study, the hypotensive effects of captopril and OKY-046, a selective inhibitor of thromboxane A2 synthetase, were studied in nine patients with essential hypertension to determine whether thromboxane A2 is involved in the regulation of blood pressure. A single oral dose of OKY-046 (400 mg) decreased urinary thromboxane B2 (a stable metabolite of thromboxane A2) excretion significantly (from 113 +/- 19.0 to 51.0 +/- 6.1 pg/min; p less than 0.01) and increased urinary sodium excretion significantly (from 73.0 +/- 15.3 to 113.0 +/- 14.4 microEq/min; p less than 0.01), but no change was observed in mean arterial pressure. The administration of OKY-046 (600 mg/day) for 3 days induced a significant and sustained decrease in urinary thromboxane B2 excretion, but it did not affect the mean arterial pressure. Although captopril (50 mg) alone induced a significant increase in urinary thromboxane B2 excretion (from 91.4 +/- 11.0 to 297.3 +/- 30.8 pg/min; p less than 0.001) and a significant decrease in mean arterial pressure (from 97.0 +/- 4.7 to 88.1 +/- 5.1 mm Hg; p less than 0.01), captopril in combination with OKY-046 induced a decrease both in urinary thromboxane B2 excretion (from 70.8 +/- 12.3 to 54.2 +/- 14.7 pg/min; p less than 0.01) and in mean arterial pressure (from 105.1 +/- 3.8 to 84.2 +/- 3.6 mm Hg; p less than 0.01). Thus, the hypotensive effect of captopril was potentiated by OKY-046. OKY-046 did not affect the changes in plasma renin activity and plasma aldosterone concentration and blunted urinary prostaglandin E2 and 6-keto-prostaglandin F1 alpha excretion in response to captopril. These results indicate that thromboxane A2 counteracts the hypotensive effect of captopril in patients with essential hypertension.

Adult↗
PubMed1988

[The inhibitory effects of chicken ovomacroglobulin on collagenolytic activity in Bacteroides gingivalis culture supernatant, human PMN and human gingival crevicular fluid].

We examined in vitro the inhibitory effects of ovomacroglobulin on collagenolytic activity in Bacteroides gingivalis (B. gingivalis) culture supernatant, in human peripheral blood polymorphonuclear leucocytes (PMN), and in gingival crevicular fluid (GCF) from periodontitis patients. Measurement of collagenolytic activity was conducted with a CollagenoKit CLN-100 using FITC-conjugated type I collagen. The FITC-conjugated collagen was reacted with the sample in solution, and the residue was selectively degenerated at 35 degrees C and removed with ethanol. The fluorescence of the removed residue was then measured. The collagenolytic activity from B. gingivalis displayed dose dependent inhibition as high as 81.4% following addition of ovomacroglobulin at 224 micrograms/ml. The collagenolytic activity from human peripheral blood PMN showed, as a result of addition of 1,600 micrograms/ml of ovomacroglobulin, inhibition as high as 62.4%. The collagenolytic activity from human GCF, which was obtained from patients with different degrees of periodontal disease, exhibited as high as 71.0% inhibition after addition of 1,600 micrograms/ml ovomacroglobulin. Ovomacroglobulin showed almost the same level of inhibition obtained from alpha 2-macroglobulin, which was measured as a positive control. It was also recognized by SDS-PAGE that collagenolytic activity was inhibited after preincubation with added ovomacroglobulin. This collagenolytic activity, which dissolved the collagen substrate, was derived from B. gingivalis and human GCF. The above results demonstrate that ovomacroglobulin inhibits collagenolytic activity from B. gingivalis, human PMN, and human GCF.

Animals↗