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Kazunari Kaneko

Publications and source records attributed to Kazunari Kaneko.

At least 19 recordsLinked to original sources

Usefulness of diffusion-weighted MRI in human herpesvirus-6 encephalitis.

UNLABELLED: We report a patient with human herpesvirus-6 (HHV-6) encephalitis diagnosed by diffusion-weighted magnetic resonance imaging (DW-MRI). A previously healthy 10-month-old girl developed acute encephalopathy. HHV-6 DNA was detected in her cerebrospinal fluid during the acute phase of the disease by polymerase chain reaction. The patient demonstrated cortical diffusion abnormalities in affected brain parenchyma, partially as the initial or most sensitive sign of encephalitis that could be detected not by conventional MRI but by DW-MRI. Serial imaging showed that the diffusion abnormality DW-MRI returned to normal after 45 days. CONCLUSION: DW-MRI may be a valuable tool for early detection and diagnosis of HHV-6 encephalitis and is more sensitive than conventional MRI to detect a subtle edematous change in the brain.

Diagnostic Errors↗

A prospective study on the use of mycophenolate mofetil in children with cyclosporine-dependent nephrotic syndrome.

Cyclosporine A (CsA) has relieved children with steroid-dependent nephrotic syndrome (NS) from steroid toxicity. However, most patients frequently relapse again when CsA is withdrawn, resulting in the development of CsA nephropathy for its long-term use. In order to assess the efficacy of mycophenolate mofetil (MMF) therapy, we prospectively analyzed 12 children with idiopathic steroid-dependent NS requiring long-term CsA therapy with MMF for at least 6 months. Mean follow-up after starting MMF was 11 months (range 6-42). The mean MMF dose required was 610+/-95 mg/m(2)/12 h, which maintained mean predose mycophenolic acid (C0-MPA) levels of 2.4+/-1.1 mcg/ml. Treatment with MMF resulted in CsA and/or prednisolone (PSL) sparing, with a reduction in mean CsA dose from 3.5+/-1.3 to 1.5+/-2.4 mg/kg/day (p<0.01), and mean PSL dose from 0.29+/-0.16 to 0.21+/-0.11 mg/kg/day (p<0.05). Nine of 12 patients (75%) were finally able to be weaned off CsA. Mean relapse rates decreased from 2.7+/-1.6 to 0.6+/-0.9 episodes/year (p<0.01). Relapse-free ratio on MMF therapy was lower in patients whose average C0-MPA levels were less than 2 mcg/ml (p<0.05). Our experience demonstrates that MMF therapy results in significant CsA and/or steroid sparing and reduction in relapse rates in children with CsA-dependent NS.

Adolescent↗

Usefulness of magnetic resonance cholangiopancreatography in biliary structures in infants: a four-case report.

In this paper, we report the usefulness of magnetic resonance cholangiopancreatography (MRCP) in excluding biliary atresia (BA) as the cause of neonatal cholestasis. MRCP with a 1.5-T magnetic resonance (MR) imaging unit was performed on four jaundiced neonates and infants aged from 38 days to 106 days. The diagnosis of BA (n=2) was confirmed with surgery, liver biopsy and surgical cholangiography. Diagnosis of neonatal hepatitis (NH, n=2) was confirmed with clinical follow-up until jaundice resolved, while one of them was diagnosed with surgical cholangiography. In all discoloured acholic stools, increased direct bilirubin (4.4-11.3 mg/dl) with positive lipoprotein X prompted technetium 99mTc disofenin scanning, which showed no excretion. Computed tomography (CT) showed a gallbladder in one with hepatitis but no intrahepatic bile duct in two with BA. The Kasai operation was performed in two patients with BA. In two patients with BA, neither the common bile duct nor the common hepatic ducts were visible at MRCP. In two patients with NH, MRCP clearly depicted both the common hepatic and the common bile ducts. MRCP was accurate in excluding BA as the cause of neonatal cholestasis, while 99mTc disofenin cholescintigraphic findings were false-positive in two patients with non-obstructive cholestasis. We conclude that MRCP can be used to depict the major biliary structures of neonates and small infants and to exclude BA as the cause of neonatal cholestasis by allowing visualisation of the biliary tract.

Biliary Atresia↗

Mechanisms underlying acceleration of blood flow recovery in ischemic limbs by macrophage colony-stimulating factor.

Recently we reported that macrophage colony-stimulating factor (M-CSF) can mobilize endothelial progenitor cells (EPCs) from the bone marrow into the peripheral blood, resulting in an increase in the number of blood vessels and augmentation of blood flow in the ischemia-induced legs. M-CSF accelerates neovascularization of ischemic lesions resulting from the mobilization of EPCs. In the present paper, we analyze the mechanisms underling the mobilization of EPCs by M-CSF. M-CSF augments the production of vascular endothelial growth factor (VEGF) from the bone marrow cells, especially from myeloid lineage cells. In vivo administration of anti-VEGF antibody abrogates both the acceleration of the recovery of blood flow in the ischemia-induced limbs by M-CSF and the augmentation of the mobilization of EPCs induced by M-CSF. These results suggest that the M-CSF contributes to rapid recovery of blood flow in ischemic lesions by mobilization of EPCs from the bone marrow through augmentation of VEGF production in the bone marrow and that the VEGF is mainly produced by myeloid lineage cells.

Animals↗

Thin basement membrane nephropathy associated with minimal change disease in a 15-year-old boy.

Thin basement membrane nephropathy (TBMN) is characterized clinically by persistent hematuria, minimal proteinuria, normal renal function, another family member with hematuria, and a benign course. Especially in childhood TBMN, proteinuria of any degree is reported to be uncommon. We report on a boy with benign familial hematuria found by urinary screening at 3 years of age who presented with nephrotic syndrome (NS) at 15 years of age. His renal histology showed TBMN associated with minimal change disease (MCD). Treatment with corticosteroid resulted in complete remission of NS in a short period of time, while isolated hematuria persisted during the follow-up period despite this therapy. We speculate, therefore, that the nephrotic range proteinuria is not due to TBMN but rather is the manifestation of associated MCD. Several cases of TBMN with NS have been reported in adults, but it has not yet been reported in children in the literature. To our knowledge, this is the first case of childhood TBMN associated with NS resulting from coincidental MCD.

Adolescent↗

High-dose mizoribine therapy for childhood-onset frequently relapsing steroid-dependent nephrotic syndrome with cyclosporin nephrotoxicity.

Cyclosporin A (CsA) is an effective treatment for frequently relapsing steroid-dependent nephrotic syndrome (FR-SDNS), but its use can be complicated by renal toxicity and a high incidence of relapses after withdrawal. We report 9 adolescent patients with childhood-onset FR-SDNS who had been treated with long-term CsA that resulted in moderate-to-severe CsA nephropathy (CsAN). They were treated with high-dose (mean: 10.1 mg/kg per day) mizoribine (MZR) in an attempt to allow weaning of CsA and/or steroid therapy, and reduce the frequency of relapses. Seven out of 9 patients were weaned off CsA by 1-year follow-up, although in the remaining 2 patients, MZR did not show any beneficial effects. Overall, this high-dose MZR therapy results in significant steroid sparing and reduction in relapse rates in our patients. Our experience shows that high-dose MZR therapy in patients with FR-SDNS who are also CsA-dependent appears to be effective in reducing CsA exposure as well as in decreasing the frequency of relapses.

Adolescent↗

Effect of a novel free radical scavenger, edaravone, on puromycin aminonucleoside induced nephrosis in rats.

Recent studies indicate that excessive production of oxidants plays a role in the pathogenesis of glomerular injury leading to proteinuria in patients with minimal-change nephrotic syndrome (MCNS). The novel free radical scavenger, edaravone (EDA), which was recently developed in Japan, is currently used in patients with stroke. We studied whether this new agent would be beneficial in patients with MCNS by its antioxidant activity and examined its effect on proteinuria in nephrosis induced by puromycin-aminonucleoside (PAN) in rats. Nineteen Wistar-Kyoto rats injected with PAN were assigned to four groups: group 1, without EDA (n=4); group 2, concomitant EDA injection from 1 day prior to PAN administration (n=5); group 3, concomitant EDA injection from 1 day after PAN administration (n=5); group 4, concomitant EDA injection from 3 days after PAN administration (n=5). Daily urinary excretions of protein and 8-hydroxy-2'-deoxyguanosine (8-OHdG), a new sensitive marker of oxidative DNA damage in vivo, were measured in each group from the 1st to the 30th day after PAN injection. In group 1 proteinuria developed from the 5th day and reached the peak level on the 9th day. In groups 2, 3, and 4 proteinuria did not appear until the 6th day. The excretions in urinary protein and 8-OHdG were significantly lower in groups 2, 3, and 4 than group 1 on days 5, 9, and 25. In conclusion, EDA could delay and ameliorate the urinary protein excretion in accordance with the urinary 8-OHdG excretion in PAN-induced nephrosis.

8-Hydroxy-2'-Deoxyguanosine↗

Induction therapy with low-dose intravenous cyclophosphamide, oral mizoribine, and steroids for severe lupus nephritis in children.

Although immunosuppressive regimens of corticosteroids combined with high-dose intravenous cyclophosphamide (IVCY) have been reported to suppress the activity of lupus nephritis, there is controversy regarding its application for children and adolescents, because of its potential toxicity including gonadal dysfunction. On the basis of the recent finding that a low-dose IVCY regimen for induction therapy in adult lupus nephritis effectively achieves renal remission comparable with that achieved with a conventional high-dose IVCY regimen, we treated two children with severe lupus nephritis by low-dose (fixed dose of 500 mg m(-2), cumulative dose 3 g m(-2), approximately one-fourth of the conventional high-dose IVCY regimen) IVCY and oral mizoribine (5 mg kg(-1) day(-1)) and steroids (3 methylprednisolone pulse followed by oral prednisolone). They responded well to this regimen, showing remarkable improvement in both histological and clinical manifestations in a short period of time. From these findings we suggest that the new low-dose IVCY regimen may be as effective as the conventional high-dose IVCY regimen, without significant adverse effect, for induction therapy in children with severe lupus nephritis (class III or IV).

Administration, Oral↗

Simplified quantification of urinary protein excretion using a novel dipstick in children.

Although the quantification of protein excretion is valuable for diagnosing and monitoring renal disease, accurate, timed, urine collection entails practical difficulties in children. Several authors have shown that the random urine protein/creatinine ratio (UP/UC) correlates well with timed protein excretion. A novel dipstick, Multistix PRO, has recently enabled us to analyze concentrations of both urinary protein and creatinine, semi-quantitatively, in 60 s. The aim of this study was to investigate whether the UP/UC values obtained by Multistix PRO correlate well with those obtained by quantitative methods and daily urinary protein excretion. In order to obtain the UP/UC values, we measured urinary protein and creatinine concentrations both semi-quantitatively by Multistix PRO and quantitatively by conventional methods. The relationship between the semi-quantitative UP/UC by Multistix PRO and the quantitative UP/UC by conventional methods was analyzed. Similarly, the relationship between the semi-quantitative UP/UC and daily urinary protein excretion was studied. Semi-quantitative UP/UC by Multistix PRO correlated closely with both quantitative UP/UC and daily urinary protein excretion (r=0.86 and r=0.91, respectively). A cut-off level of heavy proteinuria, i.e., nephrotic range of proteinuria (>3.5 g/day) corresponded to 3.0, assessed by UP/UC by Multistix PRO. The semi-quantitative UP/UC by Multistix PRO correlated well with both quantitative UP/UC and daily urinary protein excretion, and use of the Multistix PRO would avoid errors and difficulties associated with timed urine collection. It is, therefore, a useful tool to monitor the urinary protein excretion in children with renal diseases at outpatient clinic.

Adolescent↗

Outcome and cost analysis of laparoscopic or open surgery versus conservative management for multicystic dysplastic kidney.

PURPOSE: To determine whether laparoscopic nephrectomy (LN), open nephrectomy (ON), or observation (OB) is most efficient for managing multicystic dysplastic kidney (MCDK). METHODS: We performed a retrospective review of the management of our 12-year clinical experience of 32 MCDK patients to analyze the estimated total cost (ETC) of various treatment options and compare them with respect to survival, development of hypertension, and postoperative cosmetic appearance, to determine the most efficient treatment option. RESULTS: There were 12 cases in the LN group, 6 in the ON group, and 14 in the OB group. ETC was lower for ON than for LN. But the length of preoperative observation and length of follow-up after spontaneous regression greatly affected ETC. If MCDK cases were observed > 5 years with standard investigations performed regularly, ETC was higher for the OB group than for the LN group. In 6/14 (42.9%) of OB cases, MCDK resolved within 5 years, and this subgroup had the lowest ETC up to the time of this review. Six cases initially in the OB group were managed surgically (4 by LN and 2 by ON) in accordance with parental requests, and ETC in these cases was highest. All cases are well after a mean follow-up of 5.7 years, without any impairment of renal function, or hypertension. CONCLUSION: The decision to operate after lengthy observation increases costs. Overall, the most efficient surgical technique for managing MCDK was LN because of greater patient satisfaction with postoperative cosmesis. We recommend MCDK be treated by LN after a short period of observation.

Costs and Cost Analysis↗

Effects of human milk and spermine on hydrogen peroxide-induced oxidative damage in IEC-6 cells.

OBJECTIVE: Oxidative stress is intimately involved in the pathologic processes of serious diseases in the perinatal period. Human milk (HM) contains various bioactive substances, some of which are known as antioxidants, including polyamines such as spermine (SPM). We examined the antioxidative properties of HM and SPM in an intestinal epithelial cell line. METHOD: Confluent Intestinal Epithelial Cells-6 (IEC-6) cells were preincubated with 100-fold dilutions of defatted HM, bovine milk, or three artificial milks for 24 hours, followed by hydrogen peroxide (H2O2) challenge (0.5 mM, 30 min) for oxidative stress. Cells were preincubated with either HM or increasing concentrations (within the range of HM) of SPM for 24 hours followed by an H2O2 challenge (0.25 mM, 30 min). RESULTS: HM-treated cells showed the highest survival rate (50%) compared with no pretreatment (27%), bovine milk-treated (6%), or artificial formula-treated (13-16%) cells. Significantly higher survival rates were observed in the cells treated with HM (44.0%) and in those treated with 0.5, 1, or 5 microM of SPM (12.6, 13.1, or 22.2%, respectively) in comparison with the nontreated cells (7.0%). CONCLUSION: Our results demonstrated that HM and SPM alleviated H2O2-induced oxidative damage in IEC-6 cells, whereas bovine milk and artificial formula did not show any antioxidative capacity. These results suggest that HM acts as an antioxidant in the gastrointestinal tract of infants and that SPM plays an important role in the antioxidative properties of HM.

Animals↗