PubMed Health⌕ Search

Biomedical subjects

Yuichiro Yamashiro

Publications and source records attributed to Yuichiro Yamashiro.

At least 19 recordsLinked to original sources

Effects of iron-unsaturated human lactoferrin on hydrogen peroxide-induced oxidative damage in intestinal epithelial cells.

Human milk (HM) contains various bioactive antioxidants. Lactoferrin (Lf) has been assumed to be one of the major antioxidants in HM. We examined the antioxidative properties of iron-unsaturated human Lf (apo-hLf, the major form of Lf in HM) in two intestinal epithelial cell lines: (1) An intestinal epithelial cell line (IEC-6) were preincubated for 24 h with either 50 microg/mL of apo-hLf, iron-saturated human Lf (holo-hLf), iron-unsaturated bovine transferrin (apo-bTf), or 800 ng/mL of the iron-chelating compound deferoxamine (DFX), followed by hydrogen peroxide (H2O2) challenge to induce oxidative stress. Survival rates were significantly higher in the cells preincubated with apo-hLf and DFX than those preincubated with holo-hLf. (2) Caco-2 cells were preincubated with or without apo-hLf for 24 h, followed by an H2O2 challenge. Intracellular oxidative stress was assessed by a fluorescent probe, 2',7'-dichlorodihydrofluorescein diacetate (DCF-DA). Fluorescent intensity of cell images and cell homogenates was significantly lower in the cells preincubated with apo-hLF than those preincubated without apo-hLF. Our study indicates that apo-hLf alleviates H2O2-induced oxidative damage in intestinal cells due to the iron-chelating capacity. Therefore, Lf in HM may act as an antioxidant in the gastrointestinal tract (GIT).

Animals↗

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 However, most patients frequently relapse again when CsA is withdrawn, resulting in the development of CsA nephropathy for its long-term use.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↗

Surgical treatment and outcome of mega-hydronephrosis due to pelviureteric junction stenosis.

To study the surgical treatment and outcome of hydronephrosis secondary to pelviureteric junction obstruction (PUJS) that is so massive that the renal pelvis crosses over the vertebral column [mega-hydronephrosis (MH)]. Of the 40 cases of PUJS we treated over the past 5 years, 6 cases had MH secondary to PUJS (MH-PUJS) in 6 renal units and were reviewed. Incidence of MH was 15.0%. All had Anderson-Hynes dismembered pyeloplasty to treat obstructive renal pattern on technetium-99m diethylenetriaminepentaacetic acid (DTPA) scans in five and gait disturbance due to MH in one. The contralateral kidney was normal in five and dysplastic in one. Three had nephrostomy before pyeloplasty. Preoperative DTPA scans showed good renal function in four and poor in two. Plication of the entire dilated, lax renal parenchyma ("nephroplication") was performed in three to decrease the intra-renal pelvic cavity. Prenatal diagnosis was performed in three cases. Mean age at pyeloplasty was 3.5 years and mean duration of follow-up was 1.5 years. Postoperatively, two of the three who did not have nephroplication had prolonged but not obstructed renal pattern on DTPA scans, and the other case who did not have nephroplication had nephrectomy for non-functioning kidney caused by recurrent pyelonephritis 2 years after pyeloplasty. In the three who had nephroplication, DTPA scans showed acceptable to relatively good passage in all cases. The surgical treatment of MH-PUJS is challenging with no fixed guidelines. However, nephroplication may be useful during pyeloplasty to decrease the size of MH-PUJS.

Child↗

Evaluation of psychosomatic stress in children by measuring salivary chromogranin A.

AIM: To investigate the usefulness of salivary chromogranin A (CgA) and cortisol as stress markers, and the effects of distraction on the suppression of stress in children. METHODS: We examined salivary CgA and cortisol responses before and after venipuncture in hospitalized children with and without distraction using a kaleidoscope. RESULTS: Salivary CgA levels immediately after venipuncture were significantly higher than those immediately before it, and at 60 min after venipuncture they were significantly lower than those immediately after it. However, salivary cortisol showed no significant differences at any of the three time points. In contrast, distracted by the kaleidoscope, there were no significant differences in salivary CgA and cortisol levels at all three time points. CONCLUSION: In children, salivary CgA level is a useful marker of stress. As an index of the effect of distraction, the measurement of salivary CgA is useful.

Adolescent↗

Comparison of the phospholipid classes in human milk in Japanese mothers of term and preterm infants.

BACKGROUND: Phospholipids (PLs) play an essential role in the growth and brain development of infants. AIM: To investigate PL composition in human milk (HM), including lysophosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine, phosphatidylcholine (PC) and sphingomyelin (SM), from healthy Japanese mothers. Analyses were performed on colostrum, transitional milk and mature milk from mothers of preterm and term infants. METHODS: HM samples were collected from mothers of 15 term infants (term group) and of 19 preterm infants (preterm group). PL composition was determined by two-dimensional thin-layer chromatography in conjunction with phosphorus analysis. RESULTS: In both groups, the PL content (% of total lipid) of mature milk was significantly lower than in colostrum. SM and PC were the main PLs in HM, but in the preterm group, the percentage of SM in mature milk was significantly higher and PC in mature milk was significantly lower than in the term group. CONCLUSION: The transition from colostrum to mature milk leads to an increase in SM and a decrease in PC in the HM of preterm infants, along with a decrease in PL content. This is the first report to demonstrate the differences in PL composition in HM between mothers of preterm and term infants.

Adolescent↗

Usefulness of nonbreath-hold 1-shot magnetic resonance cholangiopancreatography for the evaluation of choledochal cyst in children.

OBJECTIVE: The aim of this study was to clarify the usefulness of magnetic resonance cholangiopancreatography (MRCP) for the evaluation of choledochal cyst in children. SUBJECTS AND METHODS: MRCP was performed preoperatively in 33 patients. The MRCP findings were compared with those of endoscopic retrograde cholangiopancreatography or intraoperative cholangiopancreatography. RESULTS: In all 33 patients, MRCP could detect choledochal cyst. The detection rate of a cyst in the main pancreatic duct was 62.2%, of abnormal union of the pancreaticobiliary junction (AUPBJ) was 53.3%, of dilatation or abnormalities of the main pancreatic duct was 75.0% and of a protein plug or stone was 76.9%. In patients under 2 years of age (group A), these findings were significantly lower than those of patients above 2 years of age (group B) [main pancreatic duct: 16.6% (1/6) vs 73.1% (19/26), P < 0.01; AUPBJ: 0.0% (0/6) vs 66.7% (16/24), P < 0.05; and protein plug or stone: 0.0% (0/2) vs 90.9% (10/11), P < 0.05]. The detection rate of AUPBJ in the patients with fusiform dilatation was superior to that of those with cystic dilatation [70% (14/20) vs 20% (2/10), P < 0.05]. In the patients with fusiform dilatation, the detection rate in group A was significantly lower than that in group B [0.0% (0/3) vs 82.4% (14/17), P < 0.01]; however, there was no significant difference between the 2 groups in the detection of cystic dilatation. CONCLUSION: In patients older than 2 years, MRCP should be the first-choice method for confirming the diagnosis and for ensuring accurate visualization of the pancreaticobiliary system.

Adolescent↗

Bifidobacterium breve enhances transforming growth factor beta1 signaling by regulating Smad7 expression in preterm infants.

OBJECTIVES: Transforming growth factor (TGF) beta1 displays a broad spectrum of activities in mucosal regulation, including induction of oral tolerance, potent anti-inflammatory effects, mucosal IgA expression and effects on epithelial cell proliferation and differentiation. The present study examined the effect of probiotics on the immunologic system of preterm infants in relation to TGF-beta signaling. METHODS: Subjects comprised 19 preterm infants divided into 2 groups: receiving Bifidobacterium breve supplementation (B. breve group) and without supplementation (controls). Blood samples were collected from both groups on days 0, 14 and 28 after birth. Serum cytokine levels were measured using enzyme-linked immunosorbent assay, and expression levels of the TGF-beta signaling molecule, Smad, were examined using semiquantitative reverse transcriptase-polymerase chain reaction. RESULTS: Serum TGF-beta1 level was elevated on day 14 and remained elevated on day 28 in the B. breve group. Level of messenger RNA expression was enhanced for Smad3 and reduced for Smad7 (antagonistic Smad) after B. breve administration relative to levels in controls on day 28. CONCLUSIONS: These results demonstrated that the administration of B. breve to preterm infants can up-regulate TGF-beta1 signaling and may possibly be beneficial in attenuating inflammatory and allergic reactions in these infants.

Bifidobacterium↗

Effects of extremely early enteral feeding on plasma glicentin levels in very-low-birthweight infants.

AIM: Glicentin, an active component of enteroglucagon, is considered to have a significant trophic action on the intestinal mucosa. We examined the effects of extremely early enteral feedings on the postnatal and postprandial changes in plasma glicentin levels in very-low-birthweight (VLBW) infants. METHODS: We measured the plasma glicentin concentrations before and after feedings at 1 or 2 days, 5 or 6 days and 14 days after birth in 21 VLBW infants. The subjects were randomly divided into an extremely early feeding group, which was started on breast milk within 24 h after birth, and a control group, which was started on breast milk more than 24 h after birth. RESULTS: Plasma basal concentrations of glicentin at 5 or 6 days and at 14 days after birth were significantly higher than those at 1 or 2 days after birth in the early feeding group. The basal glicentin level at 14 days after birth was significantly higher than that at 1 or 2 days. The basal levels at 5 or 6 days and at 14 days after birth in the early feeding group were significantly higher than those in the control group. Plasma glicentin concentrations after feeding were significantly higher than those before feeding at 5 or 6 days and 14 days after birth in the early feeding group, but those levels were significantly higher only at 14 days after birth in the control group. CONCLUSION: Our results suggest that extremely early enteral feedings may play an important role in the development of glicentin secretion and intestinal mucosal growth in the early period of life in VLBW infants.

Enteral Nutrition↗

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↗

Granulocytic sarcoma of the spine in a child without bone marrow involvement: a case report and literature review.

UNLABELLED: We report a 2-year-old Japanese boy without bone marrow involvement who developed a primary granulocytic sarcoma in his spinal canal. Tumour cells were positive for myeloperoxidase, MIC2, CD56 and, CD68 on formalin-fixed, paraffin-embedded tissue sections and CD13, CD33, CD45, and CD64 on acetone-fixed fresh frozen sections. Nine months after the initiation of treatment, the tumour had significantly regressed and the patient was able to walk with help. CONCLUSION: Our patient is the youngest case of granulocytic sarcoma of the spine without bone marrow involvement. Immunohistochemical methods are very helpful in establishing a diagnosis of granulocytic sarcoma.

12E7 Antigen↗