PubMed Health⌕ Search

Biomedical subjects

N Hirao

Publications and source records attributed to N Hirao.

At least 19 recordsLinked to original sources
PubMed1999

Pindolol potentiates the effect of fluoxetine on hippocampal seizures in rats.

Recent studies have shown that behavioral and neurochemical changes induced by selective serotonin (5-HT) reuptake inhibitors such as fluoxetine are potentiated by coadministration of a 5-HT1A receptor antagonist. The present study assessed the effects of concomitant administration of fluoxetine and a 5-HT1A receptor antagonist, pindolol, on focal hippocampal (HIP) seizures elicited by electrical stimulation in rats. A 10 mg/kg dose of fluoxetine, which was ineffective by itself, produced a significant increase in the afterdischarge threshold of HIP seizures when combined with pindolol at 10 mg/kg. The inhibitory effect of this combination was eliminated by pretreatment with parachlorophenylalanine, a depletor of brain 5-HT. These findings suggest that treatments designed to increase 5-HT neurotransmission inhibit the generation of HIP seizures. A combination of fluoxetine with a 5-HT1A receptor antagonist could thus be therapeutically useful for the treatment of depressive symptoms in patients with epilepsy.

Animals↗
PubMed1998

[Renal cell carcinoma detected by metastasis to the frontal sinus: a case report].

A 58-year-old man was admitted with a swelling in the frontal region. Computerized tomography scan, magnetic resonance imaging and angiography revealed a tumor in the right frontal sinus. The surgically extirpated specimen showed clear cell carcinoma which was suspected to be a metastasis from renal cell carcinoma. Subsequent urologic examination disclosed the right renal tumor. Since there were no other systemic metastases, right nephrectomy was performed. Pathologically, the renal tumor was clear cell subtype renal cell carcinoma and had the same histology as the frontal sinus tumor.

Carcinoma, Renal Cell↗
PubMed1996

Neurofibromatosis complicated with XXX syndrome and renovascular hypertension.

A 25-year-old woman with neurofibromatosis was admitted to our hospital for evaluation of hypertension. When she was 6 years old, she was diagnosed as having neurofibromatosis and XXX syndrome because of multiple café-au-lait spots, neurofibromas of the skin and mental retardation. Chromosome analysis revealed that her karyotype was 46, XX/47, XXX. Renal arteriography disclosed aneurysmal change and stenosis of the right renal artery. After right-side nephrectomy and aneurysmectomy, the kidney was autotransplanted in the left iliac fossa. Surgical procedure resulted in marked amelioration of the hypertension without medical treatment. Thus, aortorenal bypass and renal autotransplantation have emerged as the preferred revascularization operations. This is the first report of a chromosomal linkage between neurofibromatosis which is thought to be an autosomal dominant disease and the XXX syndrome.

Adult↗
PubMed1996

A case of adenosine-sensitive ventricular tachycardia in a very elderly male.

The best-known type of adenosine-sensitive ventricular tachycardia is idiopathic and of right ventricular outflow origin; however, there is little information about other types of adenosine-sensitive ventricular tachycardia. Idiopathic adenosine-sensitive ventricular tachycardia is common in the young. An 87-year-old man with ventricular tachycardia was admitted to our hospital. His ventricular tachycardia was sensitive to adenosine triphosphate, edrophonium, verapamil, and Valsalva's maneuver. He had experienced no anginal episodes. His ventricular tachycardia was thought to be idiopathic. We report this very rare case of adenosine-sensitive ventricular tachycardia, which was not derived from the right ventricular outflow tract, in a very elderly male.

Adenosine↗
PubMed1996

[Random biopsy and recurrence risk in patients with bladder cancer].

BACKGROUND: We studied the relationship between the recurrence rate of primary superficial bladder cancer and random biopsy. METHODS: We performed transurethral resection of primary superficial bladder cancer in 144 patients, and in 55 of those cases a random biopsy was also performed. The non-recurrence rate was examined in many recurrence facters. RESULTS: The non-recurrence rate in the group with random biopsy was not significantly different from that observed in the group (100 patients) without random biopsy (chi 2 test, Generalized Wilcoxon test and multivariate analysis). Because the intravesical instillation therapy is an important inhibition factor in the recurrence rate of the primary superficial bladder cancer, we further analysed the recurrence rate in two non treated groups with or without random biopsy (13 and 35 patients respectively). No significant difference in the rate of recurrence between the two groups was observed. However, we noted recurrence of bladder cancer at biopsy positions in 8/13 patients. CONCLUSION: It appears that random biopsy may have an effect on the recurrence or the implantation of tumor cells. Further studies are needed to clarify whether random biopsy is a risk factor in the recurrence rate of primary superficial bladder cancer.

Aged↗
PubMed1993

[A study of testicular tumor on magnetic resonance imaging].

Magnetic resonance imaging (MRI) was performed on 13 testes of 12 patients with testicular abnormalities. In all cases, scrotal palpation and initial clinical course had suggested malignant testicular tumors. The normal testes showed homogeneous intermediate signal intensity on T1-weighted images and high signal intensity on T2-weighted images such as the appearance of the corpus cavernosum penis. Ten patients proved to have testicular tumors. In eight of them, the tumors showed homogeneous intermediate signal intensity on T1-weighted images, while in the other two, these images showed heterogeneous signal intensity. In four patients, tumors were of homogeneous low signal intensity on T2-weighted images, while in the other six, these images showed heterogeneous signal intensity. The rate of correspondence about local staging of testicular tumor between MRI and pathological diagnosis was 70 percent. In three patients whose testes were undoubtedly malignant according to clinical findings and examination data, MRI enabled us to diagnose one case of testicular atrophy. However, MRI suggested benign disease in the other two patients; nevertheless, surgery was performed as indicated by the other findings.

Adolescent↗
PubMed1993

Administration and dosage of iohexol, a nonionic contrast medium, for dynamic renal computed tomography.

We investigated the optimal method of administering iohexol, which contains 300 mg iodine/ml (Omnipaque 300), a nonionic contrast medium, to maintain adequate renal contrast while reducing artifacts during dynamic CT scanning. In this study, 76 patients with renal disease received 10-50 ml of iohexol as follows: group I (14 patients), 20 ml injected as an intravenous bolus for 5 sec, followed by 30 ml intravenous drip infusion for 5 min; group II (18 patients), bolus of 20 ml injected for 5 sec; group III (13 patients), 20 ml diluted with sterile water (total volume 40 ml), and injected as a bolus for 8 sec; group IV (15 patients), 20 ml injection for 5 sec followed by intravenous drip infusion of 200 ml of Hartmann-Ringer's solution given at maximum speed; and group V (14 patients), 10 ml diluted with sterile water (total volume 20 ml) injected as a bolus for 5 sec. We found that corticomedullary differentiation was most distinct on the images obtained from group IV. We concluded that a lower concentration of iohexol (150 mg iodine/ml) given by intravenous fluid loading can provide superior CT images.

Adult↗
PubMed1992

Renal cortical scarring in acute pyelonephritis.

A series of 14 patients with acute pyelonephritis was evaluated for the formation of renal scarring by serial computed tomography (CT) and intravenous urography. Although the urography results were normal, CT showed renal parenchymal atrophy (cortical scarring) in 6 patients. Cortical scarring was observed to occur after 61 to 187 days, and it was slower to develop in the patients with recurrent fever lasting for 2 weeks or more in total than in those with fever for less than 2 weeks. Scarring was significantly more frequent in patients with severe renal involvement than in those with mild involvement, and scars developed at the sites of the most extensive lesions seen on the initial CT scans. Cortical scars were detected in 6 of the 7 patients in whom the lesions occupied 30% or more of the renal parenchyma. We conclude that the extent of the initial renal parenchymal involvement was the most important determinant of eventual scar formation.

Adolescent↗
PubMed1992

Phosphatidylinositol and inositolphosphatide metabolism in hypertrophied rat heart.

The accumulation of both Inositol-(1,4,5)-trisphosphate (IP3) and Inositol-(1,3,4,5)-tetrakisphosphate (IP4) after hormonal stimulation has a physiological role, possibly in altering Ca2+ levels in cardiac tissue. However, the accumulation of inositol polyphosphate under pathophysiological conditions has not been studied. In our experiments the metabolism of phatidylinositol and IP3 in cardiac myocytes as investigated. It was shown that basal levels of cytosolic phosphatidylinositol specific phospholipase C (PI-PLC), phosphatidylinositol-(4,5)-bisphosphate specific phospholipase C (PIP2-PLC) activities markedly increased in stroke-prone spontaneously hypertensive rats (SHRSP) with age compared with age matched Wistar Kyoto rats (WKY). IP3 kinase and IP3 phosphatase activities also increased in SHRSP hearts with age. Their activities increased in WKY, but to a lesser extent than in SHRSPs. These data suggest that a PI turnover pathway such as the phosphatidylinositol 4,5-bisphosphate-IP3-Ca2+ pathway or the diacylglyceride-protein kinase C pathway may have an important role in the development of hypertrophy in SHRSP heart.

Animals↗
PubMed1991

A new technique of ureteric catheterization.

Insertion of an indwelling stent catheter or ureteric catheterization using a new guide wire (the Radiofocus guide wire) was carried out in a total of 24 subjects. The subjects comprised 16 patients in whom insertion of a conventional guide wire and ureteric catheter was not possible due to previous use of an indwelling stent catheter for extracorporeal shock-wave lithotripsy (ESWL), 2 cases in whom a conventional guide wire could not be inserted due to post-ESWL formation of a stone street, 4 patients with ureteric stenosis and 2 patients with normal ureters in whom catheterization was impossible by the usual methods. Insertion of a Radifocus guide wire into the renal pelvis was successfully accomplished in all 24 cases and an indwelling catheter could be passed in 21 cases. These results suggest that the Radifocus guide wire should make a useful contribution to ESWL therapy. It can also be applied to retrograde pyelography, ureteric obstruction, and the dilation of ureteric stenosis.

Adult↗
PubMed1991

[Upper urinary tract obstruction diagnosis and treatment of congenital hydronephrosis in children].

Twenty nine children under 2 years old with congenital hydronephrosis have been treated in the last 14 years in our department. We report 4 cases which we found difficult to diagnose and treat. The diagnosis and the treatment of congenital hydronephrosis in children are discussed, especially concerning those patients under the age of 2 years. Pyeloplasty has been performed in 28 renal units out of 35 renal units. The results of the procedure were good in 82.1%, fair in 10.7%, no change in 3.6% and a lost case in 3.6%. The Aderson-Hynes dismembered technic was employed except for one renal unit in which the extrarenal pelvis was resected. Hydronephrosis in two renal units and one with nephrostomy for one year and one month improved spontaneously. Endopyelotomy was performed in 2 renal units and will be performed in one renal unit. Nephrectomy was carried out in one renal unit with renal dysplasia. A kidney with dysplasia excreted urine of several ml/day. Post-enhanced-X-ray computed tomography and T1-weighted image of magnetic resonance presented loss of function in the kidney. Degree of stenosis, position of stenosis and function of pelvis and ureter were different in each child. Children are constantly growing up and the condition of stenosis was changed in some cases. In conclusion, we should estimate the stenosis in children using several examinations.

Humans↗
PubMed1990

Computerized tomography in acute pyelonephritis: the clinical correlations.

Computerized tomography was performed on 19 patients diagnosed as having uncomplicated acute pyelonephritis. The relationship was investigated among the laboratory findings, presence of flank pain, clinical course and severity of the lesions detected by computerized tomography. In patients febrile for less than 2 weeks healing as assessed by computerized tomography took an average of 76 days. However, in patients with repeated febrile episodes occurring for longer than 2 weeks healing was delayed until an average 232 days after onset. Computerized tomography findings generally correlated well with the erythrocyte sedimentation rate, C-reactive protein level, and presence of pyuria and flank pain. However, in patients with a prolonged course computerized tomography proved to be a more reliable indicator of progress than either the results of laboratory tests or the symptoms. In conclusion, computerized tomography was useful in the diagnosis, assessment of severity and evaluation of healing of acute pyelonephritis.

Blood Sedimentation↗
PubMed1989

[A clinical study and the diagnosis in magnetic resonance imaging of renal scarring].

Twenty-nine kidneys of seventeen patients (nine boys and eight girls) with vesicoureteral reflux and repeated urinary tract infection were studied by magnetic resonance imaging for diagnosis of renal scarring and correlation between clinical data and the degree renal scarring. Renal scarring is classified into three types according to findings in magnetic resonance imaging. The degree of renal scarring are classified into five grades according to traditional grading of intravenous pyelogram. If a fine deformity of calyx is shown on intravenous pyelogram, magnetic resonance imaging demonstrates renal scarring. Magnetic resonance imaging without irradiation is exceedingly valuable for the diagnosis of renal scarring. The appearances of magnetic resonance imaging were supported by X-ray computed tomography. There is a substantial correlation between serum creatinine and the grades of renal scarring by magnetic resonance imaging. There is a substantial correlation between fever attacks and the grade of renal scarring, and there is a significant reverse correlation between the age of the onset of upper urinary tract infection and the grade of renal scarring. It is suggested that upper urinary tract infection is the most significant factor in scar formation.

Adolescent↗
PubMed1989

[A study on accumulation of cholesterol in rat prostate].

An experimental model of prostatic hypertrophy was created by freezing the urethra at the opening of the ventral prostate in rats and administering a cholesterol-rich diet to induce cholesterol accumulation. Four-week-old Fisher rats were divided into a control group, a cholesterol-rich diet group (by adding 1% cholesterol to the diet), a frozen group, and a frozen and cholesterol-rich diet group, and were reared for 5 months. The animals were killed, and the ventral prostate was removed, weighed, and the lipid was extracted. Cholesterol content was measured by an enzymatic method. A cholesterol-rich diet without freezing had no effects on the ventral prostate, and after freezing alone, the weight of the prostate was smaller than that of the control group. However, in the group cholesterol-rich diet after urethral freezing, the cholesterol content per mg of tissue increased. This indicates that cholesterol accumulation can be induced in the prostate by administering a cholesterol-rich diet after creating the proper secretory disturbance.

Animals↗
PubMed1986

Lack of evidence for existence of vitamin D and 25-hydroxyvitamin D sulfates in human breast and cow's milk.

The presence of water-soluble vitamin D and 25-OH-D sulfates in human breast and cow's milk was studied. We first confirmed that synthetic vitamin D2 and D3 sulfates could not be hydrolyzed by alkali but by acid. Breast or cow's milk was separated into milk whey containing water-soluble components and milk curd containing crude proteins and lipophilic components. The separated milk whey and curd were hydrolyzed by acid or alkali and each lipid extract was subjected to HPLC analysis. Neither peak due to vitamin D and 25-OH-D was observed in the chromatograms of acid- and alkali-hydrolyzed milk whey, whereas the peaks due to vitamin D3 and 25-OH-D3 were found in the chromatograms of both acid- and alkali-hydrolyzed milk curd and there was no significant difference between the respective peak heights. The eluates corresponding to the respective peaks observed on the latter's chromatograms were collected and subjected to UV, HPLC, GC-MS and GLC to identify the existence of vitamin D3 and 25-OH-D3, respectively. We concluded from these results that neither breast nor cow's milk contained water-soluble vitamin D and 25-OH-D sulfates, whereas they contained fat-soluble vitamin D3 and 25-OH-D3. The concentrations of vitamin D3 and 25-OH-D3 in breast milk were about 125 and 350 ng/liter, while those in cow's milk were about 420 and 270 ng/liter, respectively. The experiments on the transfer of 3H-D3 and 3H-25-OH-D3 perorally dosed to lactating rats into suckling pups through their milk also supported the above conclusion.

25-Hydroxyvitamin D 2↗