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C Hori

Publications and source records attributed to C Hori.

At least 37 records · Page 2Linked to original sources
PubMed1997

Age-related changes of urinary nitrite/nitrate excretion in normal children.

We measured the urinary excretion of nitrite/nitrate, stable metabolites of nitric oxide, using the brucine method in 90 healthy normal children (47 boys and 43 girls), aged from 1.0 to 17.1 years, to establish the age-related normal range in children. The urinary nitrite/nitrate excretion was highest in the youngest children and decreased in an age-dependent manner to reach constant levels at about 12 years of age in both sexes. The data may be useful in identifying sick children with abnormal nitric oxide production.

Adolescent↗
PubMed1997

Chronic erythropoietin treatment enhances endogenous nitric oxide production in rats.

To examine the effect of chronic administration of recombinant human erythropoietin (rHuEPO) on endogenous nitric oxide (NO) activity, we treated Sprague-Dawley rats with rHuEPO (100 IU kg-1 or 300 IU kg-1) or a corresponding vehicle for 2 weeks, administered subcutaneously on alternate days. Treatment elicited increases in haematocrit and systolic blood pressure in a dose-dependent fashion. Simultaneous administration of NG-nitro-L-arginine methyl ester (L-NAME, 20 mg dl-1 of drinking water), but not aminoguanidine (400 mg dl-1), induced a further significant rise in blood pressure. The effect of L-NAME was inhibited by a large dose of L-arginine (2.0 g dl-1). Polycythaemia and hypertension induced by chronic rHuEPO therapy were associated with increased urinary NO2- and NO3- (NOx-) excretion, while co-administration of L-NAME, but not aminoguanidine, reduced NOx- excretion. Our results indicate that chronic rHuEPO treatment has a significant pressor effect, but induces a compensatory increase in the steady-state release of NO by constitutive NO synthase in normal rats. Such enhanced NO synthesis may act as a protective mechanism against the hypertensive effect of rHuEPO.

Animals↗
PubMed1997

[Granulocyte colony stimulating factor (G-CSF) producing renal cell carcinoma].

A 88-year-old male patient with G-CSF producing renal cell carcinoma is reported. The patient was admitted to our hospital complaining of macrohematureia. The laboratory examination showed marked leukocytosis of 18,200/microliter (neutrophil 92%) in the peripheral blood and high levels of G-CSF (120 pg/ml) in the serum. An abdominal CT scan revealed a right renal tumor. The neutrophil count rose to 38,700/microliter with increasing of tumor size. Histopathological diagnosis was renal cell carcinoma (Grade 3) and immunohistochemical staining using Histo anti-G-CSF antibody demonstrated cancer cells produced G-CSF. This is the second case of G-CSF producing renal cell carcinoma diagnosed by immunohistochemical staining in the literature.

Aged↗
PubMed1996

Two distinct long-chain-acyl-CoA synthetases in guinea pig Harderian gland.

Two distinct long-chain-acyl-CoA synthetases which have different kinetic properties were identified in the guinea pig Harderian gland. One was localized in the microsomes and the other in the mitochondria. The relative V(max) values of the microsomal enzyme were 8.1, 1.7 and 1 and the apparent Km values were 66.7, 12.0 and 30.0 microM for palmitic, linoleic and arachidonic acids, respectively. The relative V(max) values of the mitochondrial enzyme were 2.7, 3.5 and 1 and the apparent Km values were 33.3, 29.9 and 30.0 microM for palmitic, linoleic and arachidonic acids, respectively. The relative V(max) values for the liver microsomal enzyme were 2.0, 2.5 and 1, while those of the liver mitochondrial enzyme were 4.1, 3.9 and 1 with palmitic, linoleic and arachidonic acids, respectively. There were no difference between the microsomal and the mitochondrial enzymes in the liver, regarding apparent Km values; these were 38.4, 29.9 and 22.0 microM for palmitic, linoleic and arachidonic acids, respectively. Thus, the substrate specificity and catalytic rate of the mitochondrial enzyme in Harderian gland for palmitic, linoleic and arachidonic acids were similar to the liver enzyme, but not to the microsomal enzyme in Harderian gland. On the other hand, the antiserum raised against the rat liver enzyme immune-titrated and immuno-blotted the enzymes from Harderian gland microsomes and liver, but not so the enzyme from Harderian gland mitochondria. Thus, the microsomal enzyme in Harderian gland had a common immunogenic epitope(s) with the liver enzyme, but the mitochondrial enzyme did not. The Harderian gland mitochondrial enzyme was a distinct protein from liver enzymes. The catalytic and immunogenic characteristics suggest that the enzyme proteins in the Harderian gland are unique, that is, different from that in the liver. The large V(max) value of the Harderian gland microsomal enzyme for palmitic acid suggests that it contributes to the synthesis of a large amount of the secretory lipid and the high Km value to maintenance of cellular lipid in this organ. The evidence that long-chain-acyl-CoA synthetase in the mitochondria is distinct from that in the microsomes was first found in guinea pig Harderian gland.

Animals↗
PubMed1996

Urinary excretion of pyridinium cross-links of collagen in infancy.

This cross-sectional study evaluated urinary excretion of pyridinium cross-links of collagen, specific markers of ongoing bone resorption, in infants aged 1 week to 7 months and examined the relationship between urinary cross-links and individual renal function. Spot urines from a total of 100 infants were analyzed. The collagen cross-links, pyridinoline (Pyd) and deoxypyridinoline (D-Pyd), were assayed by fluorescence detection after high-performance liquid chromatography (HPLC). Beta2-Microglobulin (beta2M), an index of renal tubular function, was determined by radioimmunoassay. In healthy term infants, urinary collagen cross-links were several times higher than the reported data for older children, with peak values seen at 1 month of age. Excretion of Pyd and D-Pyd was also markedly elevated in 1-month-old preterm infants, despite poor somatic growth. Such high excretion of collagen cross-links probably reflects the state of accelerated bone turnover in infancy. The postnatal change in the cross-links was different from that in urinary beta2M, and the values obtained did not correlate with beta2M in either term or preterm infants. These results indicate that cross-link excretion is not influenced directly by individual renal function.

Amino Acids↗
PubMed1996

Urinary uric acid excretion in term and premature infants.

OBJECTIVE: To clarify postnatal changes in urinary uric acid (UA) excretion in normal term infants and to examine the effects of prematurity or illness on the UA excretion. METHODOLOGY: Measurements of urinary UA were performed in term and premature infants at the ages of 1 and 7 days and at 1 and 4 months, as well as 7 months in term infants. RESULTS: Urinary UA levels were lowest on day 7 in term infants. The levels were highest on day 1 in premature infants and remained significantly higher compared to term babies during the first month of life. Respiratory failure requiring ventilation and oxygen supply resulted in further significant elevation of urinary UA in premature infants. CONCLUSIONS: With the reference values obtained in the study reported here, urinary UA can now be used for the diagnosis and monitoring of inherited disorders of purine metabolism and for the assessment of oxygen radical insult to sick infants.

Age Factors↗
PubMed1996

Ultrasonography for the detection of ureteric reflux in infants with urinary infection.

Several less harmful methods than voiding cysto-urethrography for detecting significant ureteric reflux have been proposed. The present prospective study investigated whether ultrasonography was effective in identifying ureteric reflux in infants with their first febrile urinary infection. The subjects were 27 infants (24 boys and 3 girls) aged from 0 to 8 months. The urinary tract was scanned when the bladder was full, and before and during induced voiding. Infants with abnormal ultrasound findings underwent voiding cysto-urethrography. The other infants were followed and those who had a recurrence of urinary infection underwent voiding cystography. Ten children underwent cysto-urethrography, with eight refluxing ureters identified in six boys. Ultrasound revealed transient dilatation of the renal pelvis on voiding in five kidneys, transient dilatation of distal ureters in 12 and hydro-ureteronephrosis in two. Each of the five kidneys with pelvic dilatation on voiding was associated with ureteric reflux grades III or IV. Of the 17 children who did not undergo cysto-urethrography, only one had recurrence of urinary infection and was diagnosed with ureteric reflux. This girl was one of the three babies who were not scanned during voiding. More than half of the infants with febrile urinary infection were excluded from invasive examination without having recurrence of urinary infection. Thus, ultrasound scanning during voiding was effective for screening infants with their first urinary infection to detect significant ureteric reflux.

Diagnosis, Differential↗
PubMed1996

A case of ureteral reflux identified by ultrasound.

Reflux nephropathy is known to be a major cause of renal failure in children. Vesico-ureteral reflux is usually diagnosed by voiding cysto-urethrography (VCG). However, it has been observed that conventional VCG is not always reliable for the diagnosis of ureteral reflux. In the case of a 5 year old girl with recurrent febrile urinary tract infection, VCG showed no ureteral reflux. Urodynamic study revealed a large bladder capacity and significant residual urine. Renal scintigram delineated a right renal scar. Simple ultrasound examination with videotape recording during voiding definitely demonstrated the presence of significant ureteral reflux when she voided, that is, there was marked dilatation of the right distal ureter and ballooning of the right renal pelvis on voiding, and quick refilling of the bladder concomitantly with the disappearance of the pelvic ballooning. Therefore, an ultrasound during voiding may be useful for diagnosing ureteral reflux in patients where a VCG does not reveal reflux.

Child, Preschool↗
PubMed1996

Renal functional measurements in young rats with chronic inhibition of nitric oxide synthase.

The purpose of the present study was to examine renal functional changes caused by chronic blockade of nitric oxide (NO) synthesis in young rats. Two types of NO synthase inhibitor were used: NG-nitro-L-arginine methyl ester (L-NAME) as a non-selective inhibitor and aminoguanidine (AG) as a selective inhibitor of the inducible isoform. Oral administration of L-NAME (20-80 mg/dL of drinking water), not AG (400 mg/dL), for 4 weeks induced systemic hypertension in the treated rats. Both inhibitors caused a significant reduction in urinary excretion of NO2-/NO3-. Rats treated with L-NAME developed proteinuria and tubular enzymuria (high excretion of N-acetyl-beta-D-glucosaminidase) in a dose-dependent fashion, with normal serum levels of creatinine, albumin and cholesterol. Chronic AG administration did not alter the urinary levels of protein and N-acetyl-beta-D-glucosaminidase or serum laboratory values. Overall, these observations highlight the importance of the continuous generation of NO by the constitutive isoform in the control of vascular tone and the maintenance of renal glomerular and tubular function. Oral administration of L-NAME may serve as a model of chronic NO-deficient hypertension with renal injury in young rats.

Animals↗
PubMed1996

Ultrasonographic findings of acute tubulointerstitial nephritis.

Three children were diagnosed as having acute renal failure due to acute tubulointerstitial nephritis (TIN) associated with Yersinia pseudotuberculosis infection. The kidneys were observed ultrasonically during the disease course. The subjects presented with remittent fever, vomiting or diarrhea, and nonoliguric acute renal failure with sterile pyuria and tubular reabsorptive dysfunction. Ultrasound examination delineated marked enlargement of the kidneys with diffuse hyperechogenicity in the cortex, suggesting the diagnosis of TIN. The renal swelling was marked in the descending order of width, depth and length, respectively, and reached more than 200% in volume in 1 of the children who was examined at the culminating stage of acute renal failure. The enlarged kidneys reduced in size in parallel as the elevated serum creatinine levels decreased. However, the enlarged kidneys did not seem to return to their original sizes: the kidney size in 1 of the children remained well above the upper allowance limit of the body-height-related normals and in the other 2 they were only a little smaller than the upper limits. These ultrasound findings should help with the diagnosis and follow-up of the disease.

Acute Disease↗
PubMed1996

Urinary selenium excretion in infancy: comparison between term and preterm infants.

We evaluated the urinary excretion of selenium (Se), an essential component of glutathione peroxidase, in infants aged 1 week and 1, 4, and 7 months and examined the relationship between urinary Se and renal function. Daytime spot urine samples from a total of 80 infants were analyzed. The Se concentration in urine was measured by fluorometry, while the beta 2-microglobulin content, an index of renal tubular function, was determined by radioimmunoassay. In healthy term infants, the urinary Se excretion showed a peak level at 1 month of age. In contrast, the urinary Se concentration rapidly decreased in preterm infants from 1 week to 7 months postnatally. The level at 1 week in preterm infants was significantly higher than that in term infants, although the mean levels at 1, 4, and 7 months were lower in preterm infants. The level of urinary Se did not correlate significantly with the beta 2-micro-globulin concentration, either in term or preterm infants at any age investigated. Our results suggest that the renal excretion of Se probably reflects the body stores of Se and is not related directly to the renal function in infants. Urinary Se, a noninvasive marker of the Se status, may be used for diagnosis and follow-up of Se deficiency in infants.

Aging↗
PubMed1995

Acute tubulointerstitial nephritis in association with Yersinia pseudotuberculosis infection.

A 4-year-old girl was diagnosed as having acute renal failure due to tubulointerstitial nephritis. The girl presented with remittent fever, vomiting and non-oliguric acute renal failure with sterile pyuria and tubular reabsorptive dysfunction. Ultrasound examination revealed that the kidneys were markedly enlarged with diffuse hyperechogenicity in the cortex when the abnormal renal function was present and were restored in size and echogenicity when the renal function normalised. A diagnosis of Yersinia pseudotuberculosis infection was based on a rise in haemagglutination titres against the organism.

Acute Disease↗
PubMed1995

Ultrasonographic evaluation of bladder volume in young children.

We investigated by ultrasonography the bladders of 30 young children (26 boys, 4 girls) without established bladder control immediately before voiding cystourethrography. The anterior/posterior (D), superior/inferior (H) and transverse dimension (W) of the bladder were determined. The small children had a significantly greater H value compared with D and W than older children in our previous study in 1993. The regression equation for D x H x W and actual bladder volume in 30 infants was calculated as y = 0.49 x + 3 (Eq. 1). When bladder volume of the 30 infants was estimated from D x H x W, the mean percentage error was much lower with Eq. 1 than with Eq. 2 (y = 0.68 x + 4), which had been determined for older children (mean +/- SD 16.8% +/- 10.7% vs. 44.7% +/- 26.2%) (P < 0.01). Thus, infants have a different bladder shape than older children and their bladder volume should be estimated using a specific formula designed for them.

Child, Preschool↗
PubMed1995

Left renal pelvis of male neonates is predisposed to dilatation.

Dilatation of the renal pelvis has been observed as an ultrasonographic finding of ureteral reflux as well as hydronephrosis. However, little information is available on the prevalence of renal pelvis at dilatation in neonates. We measured the inner pelvis dimension of the kidneys in 511 apparently healthy neonates (279 boys and 232 girls) using an ultrasound scanner to determine the prevalence of renal pelvis dilatation. Ninety per cent of the neonates had an inner dimension of both renal pelvises below 5 mm. The prevalence of left renal pelvis dilatation of 5 mm or more was significantly higher in the boys than in the girls, 25 (9%) compared to 5 (2%). In contrast, no significant difference was found in the prevalence of right renal pelvis dilatation between the sexes. In the boys, the prevalence of renal pelvis dilatation of 6 mm or more was significantly higher on the left side than on the right. Moreover, the left renal pelvis dilatation of the male neonates had a tendency to persist at 1 month of age. These findings suggest that the left renal pelvis of the baby boy may be predisposed to dilatation.

Chi-Square Distribution↗
PubMed1995

Urine microscopy on a counting chamber for diagnosis of urinary infection.

Several quantitative methods of urine microscopic examination for bacteriuria and pyuria on a blood cell counting-chamber have been found reliable for the diagnosis of urinary tract infection (UTI). However, no one technique has become popular or widely used because of laborious procedures associated with the method. We investigated the usefulness of microscopic examination of uncentrifuged urine on disposable counting-chambers. A total of 89 urine samples were obtained from 53 children (24 male and 29 female). Urine samples were examined for bacteriuria and pyuria using a disposable counting chamber and its reliability was analyzed in predicting significant bacteriuria defined by routine urine culture. Significant bacteriuria was diagnosed in 23 of 89 urine samples by urine culture. Microscopic urine examination on disposable counting-chambers was very easy without the need to set up or wash chambers and provided immediate information. Urine bacterial concentration determined by the counting-chamber method was closely correlated to that determined by bacterial culture. The counting-chamber method identified bacteriuria correctly in 21 of 23 urine samples diagnosed as significant bacteriuria (sensitivity = 91%) and also gave a correct diagnosis of 64 of 66 urine samples with non-significant bacteriuria (specificity = 98%). Nineteen of the 23 urine samples with significant bacteriuria also had pyuria. The positive predictive value of concomitant bacteriuria and pyuria was 100%. When neither bacteriuria nor pyuria was found, the negative predictive value was 100%. It was concluded that urine microscopy using disposable counting chambers was very easy, inexpensive, quick and reliable and thus an extremely useful method for diagnosing UTI.

Adolescent↗