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Biomedical subjects

S Tokunaga

Publications and source records attributed to S Tokunaga.

At least 91 records · Page 5Linked to original sources
PubMed1994

Effects of a novel dihydropyridine calcium antagonist on venous capacitance in Wistar-Kyoto rats.

Calcium antagonists are potent dilators of resistance vessels but do not dilate capacitance vessels. CD832 is a novel dihydropyridine calcium antagonist which has a nitrate moiety in its chemical structure. The authors examined the effects of CD832 on venous capacitance in anesthetized rats. Venous capacitance was assessed by measuring mean circulatory filling pressure (MCFP) at three levels of blood volume. Nitroglycerin decreased and phenylephrine increased MCFP. CD832 did not alter MCFP. After treatment with hexamethonium to prevent reflex venoconstriction, CD832 significantly decreased MCFP but nicardipine (another dihydropyridine calcium antagonist) did not. The magnitude of hypotension caused by CD832 and nicardipine was comparable. The results suggest that CD832 is a unique calcium antagonist which has a venodilator effect.

Animals↗
PubMed1993

Association between blood polychlorinated biphenyl concentration and serum triglyceride level in chronic "Yusho" (polychlorinated biphenyl poisoning) patients.

The association between blood polychlorinated biphenyl (PCB) concentration and serum triglyceride level was investigated in 259 "Yusho" patients (PCB poisoning) who underwent health examinations for Yusho in 1988. Geometric means of PCB and triglyceride were 3.84 ppb (95% confidence interval: 3.54-4.17) and 114.3 mg/dl (106.6-122.6), respectively. Both correlation and multiple regression analyses showed a weak but statistically significant correlation between these two variables. The mean triglyceride level adjusted for age and sex was then calculated for comparison among four PCB levels, using analysis of covariance. This indicated a progressive increase with increasing PCB: 98.36, 117.78, 117.84, and 127.65 mg/dl at < 2.7, 2.7+, 4.1+, and 6.1+ ppb, respectively (F = 2.01, P = 0.113). Comparing PCB levels, the difference in adjusted mean triglyceride levels was marginally significant between the first and second (P = 0.088), and the first and third quartiles (P = 0.066), and reached significance between the first and fourth quartiles (P = 0.021). Thus, a weak but significant association between blood PCB and serum triglyceride was observed in the patients 20 years after exposure, although their blood PCB and serum triglyceride were relatively close to the normal levels.

Adult↗
PubMed1993

An experimental model of ascending pyelonephritis due to Candida albicans in rats.

We developed a new experimental model of ascending Candida pyelonephritis in female rats with leukopenia and vesicoureteral reflux. Rats were treated transperitoneally with cyclophosphamide (200 mg/kg) to induce leukopenia 3 days before and transurethrally with diluted acetic acid solution to induce vesicoureteral reflux 1 day before inoculation of Candida albicans strain, ATCC 10259 (containing 10(7) cells). Microscopy revealed acute pyelonephritis in which Candida cells invaded from the fornix and/or papilla into the medulla within 3 days after inoculation. Between 7 and 28 days after inoculation, chronic pyelonephritis reached the cortex. The incidence of pyelonephritis increased gradually and was approximately 80% after 7 days. Candida colony counts of bladder urine specimens obtained by direct puncture were significantly greater in rats with pyelonephritis extending into the parenchyma than in those with pyelonephritis located along the pelvis (p < 0.01). These results suggest that this rat model shows the characteristic feature of ascending pyelonephritis due to C. albicans and that the severity of Candida pyelonephritis can be estimated from Candida counts of bladder urine.

Animals↗
PubMed1993

Diagnostic value of determination of serum mannan concentrations in patients with candiduria.

The diagnostic value of determination of serum mannan levels was studied in 41 patients with candiduria and 20 control patients without candiduria. The patients with candiduria comprised 18 asymptomatic afebrile patients (group 1) and 23 febrile patients with suspected Candida pyelonephritis (group 2). Mannan antigenemia (> or equal to 0.5 ng/ml) was detected in 14 patients in group 2, this rate being significantly higher than the rate of four patients in group 1 (p < 0.05) and none in the control group (p < 0.01). Serum mannan levels decreased gradually and became undetectable in six patients in whom therapy with an anticandidal agent was effective. Determination of serum mannan levels may be a useful parameter in diagnosing Candida pyelonephritis and deciding on effective treatment.

Antigens, Fungal↗
PubMed1993

Percutaneous injection sclerotherapy with minocycline hydrochloride for simple renal cysts.

Minocycline hydrochloride as a sclerosant for the treatment of simple renal cysts was evaluated. Cyst puncture was performed, and minocycline hydrochloride solution for intravenous administration was injected after aspiration. Of 154 cysts evaluated by ultrasound after 3 months or more, 69 were no longer demonstrable, 49 showed 50% or greater reduction in the maximum cyst diameter, and only 8 were unchanged or slightly increased in size. In contrast, only 1 of 20 cysts aspirated without minocycline hydrochloride injection (controls) showed 50% or greater reduction after 3 months. There was a significant difference in the reduction rates between the minocycline-treated group and control group (p < 0.01). These results suggest that minocycline hydrochloride is an effective sclerosant to treat simple renal cysts.

Female↗
PubMed1993

Trans-ventricular septal defect approach for resection of accessory mitral valve tissue.

Accessory mitral valve tissue is a rare cause of left ventricular outflow tract obstruction, which can be difficult to recognize. Surgical resection by the conventional transaortic approach with or without left atriotomy is extremely difficult in infants with a small aorta. When a ventricular septal defect is present, it may be the best way to approach the accessory mitral valve tissue, because the ventricular septal defect is located just in front of it. Five infants underwent resection of accessory mitral valve tissue together with repair of other intracardiac malformations. In 3 infants, resection of accessory mitral valve tissue was easily performed through the ventricular septal defect, which required enlargement in 2 patients.

Female↗
PubMed1993

Ureaplasma urealyticum in the urogenital tract of patients with chronic prostatitis or related symptomatology.

To elucidate the role of Ureaplasma urealyticum as a causative organism in chronic prostatitis we investigated its incidence in the urogenital tract in 131 chronic prostatitis patients and 120 prostatodynia patients; the presence of common bacteria or Chlamydia trachomatis was also recorded. According to the 4-glass localisation test, U. urealyticum (> or = 10(3) ccu/ml) was isolated from the prostates of 16 prostatitis patients and 2 prostatodynia patients; 5 of these prostatitis patients (but neither of the prostatodynia patients) had other bacteria in specimens after prostatic massage. Thus U. urealyticum was the sole organism isolated from the prostates of 11 prostatitis and 2 prostatodynia patients, which suggests that it is an aetiological agent in some cases of chronic non-bacterial prostatitis.

Adult↗
PubMed1993

Spontaneous passage of upper urinary tract calculi in relation to composition.

The composition of 2,755 calculi obtained from the upper urinary tract (1,409 by spontaneous passage and 1,346 by urological procedures) was analyzed using an infrared spectrophotometer, and the spontaneous passage rate was investigated in relation to the composition as well as other variables, such as stone size, and patient age and sex. Mixed stones of calcium oxalate and calcium phosphate were most frequently found, followed by those of calcium oxalate. The mean size (the maximum diameter) was largest in struvite stones and smallest in calcium oxalate ones. The sizes of stones from women were significantly larger than those from men (p < 0.01). As expected, the stone passage rates were inversely related to increasing stone size. The size of 55.6% of the stones passed was < or = 5 mm, and that of 96.6% of the stones < or = 10 mm.

Adolescent↗
PubMed1993

Antimicrobial treatment for chronic prostatitis as a means of defining the role of Ureaplasma urealyticum.

A study was conducted to assess the clinical and microbiological effects of antimicrobial treatment for chronic prostatitis as a means of defining the role of Ureaplasma urealyticum. Significant U. urealyticum cells were considered to be isolated from the prostates of 18 of 143 prostatitis patients. These patients with ureaplasma-associated prostatitis were randomly treated with either ofloxacin or minocycline for 2 weeks; 4 patients were excluded due to voluntary withdrawal. U. urealyticum was eradicated in all the patients. Symptoms were resolved in 10 patients, and leukocytes in expressed prostatic secretion were cleared in 4 patients; both drug treatments revealed similar results. Even if we exclude 3 patients with significant coexistent Staphylococcus epidermidis cells before treatment, 3 of 11 patients evaluated showed complete resolution of symptoms and clearance of leukocytes in expressed prostatic fluid. These results suggest that U. urealyticum is a causative organism in some patients with chronic prostatitis.

Adult↗
PubMed1993

Inhibition of nitric oxide formation in the nucleus tractus solitarius increases renal sympathetic nerve activity in rabbits.

It has been shown that nitric oxide (NO) is synthesized in the central nervous system as well as in vascular endothelial cells. However, the physiological role of NO in cardiovascular regulation by the central nervous system remains unclear. This objective of this study was to examine the possibility that NO plays a role in neural transmission in the nucleus tractus solitarius (NTS) and thus contributes to control of sympathetic nerve activity in rabbits. We examined the effects of NG-monomethyl-L-arginine (L-NMMA), an inhibitor of the formation of NO from L-arginine, microinjected into the NTS on arterial pressure (AP), heart rate (HR), and renal sympathetic nerve activity (RSNA). L-NMMA increased AP and RSNA in rabbits with intact as well as denervated sinoaortic baroreceptors and vagi. L-NMMA increased HR only in rabbits with sinoaortic denervation and vagotomy. Pretreatment with L-arginine microinjected into the NTS, which did not alter baseline AP, HR, and RSNA, prevented the increases in AP and RSNA evoked with subsequent L-NMMA. Pretreatment with D-arginine did not alter the effects of subsequent L-NMMA injections into the NTS. The gain of arterial baroreflex control of RSNA assessed by the slope of the regression line relating changes in AP and those in RSNA caused by intravenous phenylephrine or nitroglycerin did not differ before and after microinjections of L-NMMA. L-NMMA microinjected into the area postrema did not alter AP, HR, or RSNA. These results suggest that in rabbits NO is involved in the mechanism in the NTS that mediates tonic inhibition of RSNA.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Pharmacokinetics of temocapril and enalapril in patients with various degrees of renal insufficiency.

Temocapril is a novel ACE inhibitor that is cleared via dual excretion routes in humans. Borderline or mildly hypertensive patients with normal renal function [group 1, creatinine clearance (CLCR) > 70 ml/min (4.2 L/h), n = 12], moderate renal impairment [group 2, CLCR 30 to 70 ml/min (1.8 to 4.2 L/h), n = 12] or severe renal impairment [group 3, CLCR < 30 ml/min (1.8 L/h), n = 12] received a single oral dose of either temocapril 1 mg (n = 6, each group) or enalapril 5mg (n = 6, each group). These 2 drugs gave similar values for the area under the plasma concentration-time curve (AUC) of the active diacids. The maximum plasma concentration of enalapril diacid was increased 2- and 6-fold in moderate and severe renal impairment, respectively, whereas that of temocapril diacid was not altered. The AUC of enalapril diacid increased 13-fold at CLCR values < 30 ml/min, but that of temocapril diacid increased only 2-fold. The duration of plasma ACE inhibition due to enalapril was greatly prolonged by the impairment of renal function, whereas that due to temocapril was affected very little. Urinary recovery of temocapril diacid was decreased markedly in patients with severe renal dysfunction, most probably because the diacid was excreted through the biliary route. On the other hand, urinary recovery of enalapril diacid remained fairly high even in patients with severe renal impairment, because of extremely high plasma diacid concentrations resulting from the lack of biliary excretion. These observations suggest that temocapril is beneficial in the treatment of hypertension in patients with severely impaired renal function.

Adult↗
PubMed1993

Drug resistance of coagulase-negative staphylococci from patients with urinary tract infection.

The drug resistance of 202 coagulase-negative staphylococci (CNS) strains isolated from patients with urinary tract infection (UTI) at urinary colony counts of 10(5) or more between 1989 and 1991 was studied. Of the 202 strains, 185 were submitted from UTI patients with underlying urinary disorders (complicated UTI patients) and became rapidly resistant to the majority of drugs tested. In addition, the incidence of methicillin-resistant or multiple drug resistant CNS tended to increase. These resistant strains were significantly more frequently isolated in patients with fever, which was strongly suspected to be due to CNS UTI. These results suggest that the prevalence of drug resistance in CNS from the urinary tract rapidly increases and drug-resistant CNS aggravate CNS UTI.

Anti-Infective Agents, Urinary↗
PubMed1993

[Local recurrence of non-functioning adrenocortical carcinoma 14 years following surgical treatment: a case report].

A 76-year-old woman with a complaint of left flank pain was referred to our department for extensive examination and treatment. In 1976, she had undergone transperitoneal left adrenalectomy and nephrectomy under a diagnosis of left adrenal tumor. The surgical specimen had histologically been diagnosed as adrenocortical carcinoma. There have been no physical or endocrinological abnormalities. Computed tomogram, magnetic resonance imaging and angiogram revealed a retroperitoneal multiple hypervascular tumor with a non-homogeneous inner density. On January 16, 1991, a transperitoneal resection of the tumor with splenectomy and partial pancreatectomy was performed under a diagnosis of local recurrence of non-functioning adrenocortical carcinoma. The specimen was histopathologically diagnosed as low grade adrenocortical carcinoma based on 3 mitoses/50 hpf. From the reference study, this was thought to be the second case of late recurrence adrenocortical carcinoma.

Adrenal Cortex Neoplasms↗
PubMed1992

Induction of coronary artery spasm by intracoronary acetylcholine: comparison with intracoronary ergonovine.

To investigate the mechanism of coronary spasm, we compared the action of acetylcholine with that of ergonovine in 11 patients with vasospastic angina (group 1) and in 15 patients with chest pain (group 2). Coronary arteriography was performed immediately after the patients received intracoronary injections of titrated increments of each agent. In the patients in group 1 occlusive or near-occlusive (99% luminal narrowing) coronary spasm associated with angina and ischemic electrocardiographic ST changes was noted in nine of 11 patients receiving acetylcholine and in all 11 patients receiving ergonovine. The region and the degree of the most severe coronary spasm on coronary arteriograms evoked by the two agents were the same in nine of the 11 patients in group 1. In the other two patients in group 1, spontaneous focal coronary spastic stenosis in the baseline coronary arteriogram was relieved by the intracoronary injection of acetylcholine, and a focal coronary occlusive spasm in the same region was induced repeatedly by the subsequent intracoronary injection of ergonovine (paradoxic phenomenon). In contrast, occlusive or near-occlusive coronary spasm was not induced by either agent in any patient in group 2. These results suggest that the two provocative tests for coronary spasm that involve acetylcholine and ergonovine are clinically useful in the diagnosis of vasospastic angina, but testing with intracoronary ergonovine is needed when a spontaneous focal coronary spasm is relieved by the intracoronary injection of acetylcholine. The results also indicate that in many patients with vasospastic angina, nonspecific hypersensitivity to acetylcholine or ergonovine in a definite region of the coronary arteries generally plays an important role in the induction of coronary spasm.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcholine↗
PubMed1992

Composition of urinary calculi related to urinary tract infection.

The composition of 3,084 urinary calculi was determined using an infrared spectrophotometer. Mixed calcium oxalate-calcium phosphate stones were most frequently implicated. Of the urinary calculi analyzed 199 were associated with urinary tract infection. Escherichia coli was most frequently isolated (43 strains) and urease-producing organisms, such as Proteus mirabilis, were cultured from 40 patients. The core culture of 20 staghorn calculi yielded 15 isolates from 14 stones. There were 13 identical species isolated from the urine and stone specimens of 13 patients (65%), including 7 strains of P. mirabilis. These results suggest that cultures of urine specimens of urolithiasis patients, especially those with staghorn calculi, may help to elucidate the bacteriology of the stones.

Adolescent↗
PubMed1992

Thiazide treatment for calcium urolithiasis in patients with idiopathic hypercalciuria.

In a randomised trial based on a parallel design to determine the prophylactic effect of thiazide on stone formation, 210 calcium urolithiasis patients with idiopathic hypercalciuria were allocated either to treatment with trichlormethiazide (4 mg/day) or no treatment with only close follow-up; 35 patients were excluded for various reasons, including voluntary withdrawal. The background of the remaining 175 patients (82 in the thiazide group and 93 in the control group), including age and sex, was similar for both groups. In patients treated with thiazide there was a statistically significant fall in urinary calcium output. Statistical analyses also demonstrated that the stone formation rate in the thiazide group was significantly less than that in the control group. Adverse clinical reactions probably due to the drug were observed in 9 patients. These findings indicate that trichlormethiazide has a prophylactic effect on calcium urolithiasis in patients with idiopathic hypercalciuria.

Adult↗
PubMed1992

A clinical study on patients with urinary tract infection due to coagulase-negative staphylococci.

To assess the clinical significance of coagulase-negative staphylococci (CNS) in patients with urinary tract infection (UTI), the clinical characteristics of a total of 117 patients (106 complicated UTI patients, 11 uncomplicated UTI patients) from whom CNS were isolated at urinary colony counts of 10(5) or more per ml were studied. Of the complicated UTI patients, 95 patients (89.6%) suffered from no symptoms while 11 (10.4%) had fever of 38 degrees C or greater, which was strongly suspected to be due to genitourinary tract infections. Six of these patients were managed by indwelling urinary catheters. On the other hand, all of the patients with uncomplicated UTI were young women and had typical symptoms of acute cystitis. These results suggest that CNS, which hitherto have been considered mere contaminants or benign colonization rather than true pathogens, can also cause complicated UTI requiring chemotherapy under certain conditions such as indwelling urinary catheterization and acute cystitis in sexually active women.

Adult↗