Disruption of the temporally regulated cloaca endodermal ß-catenin signaling causes anorectal malformations.

The cloaca is temporally formed and eventually divided by the urorectal septum (URS) during urogenital and anorectal organ development. Although congenital malformations, such as anorectal malformations (ARMs), are frequently observed during this process, the underlying pathogenic mechanisms remain unclear. ß-Catenin is a critical component of canonical Wnt signaling and is essential for the regulation of cell differentiation and morphogenesis during embryogenesis. The expression of ß-catenin is observed in endodermal epithelia, including URS epithelia. We modulated the ß-catenin gene conditionally in endodermal epithelia by utilizing tamoxifen-inducible Cre driver line (Shh(CreERT2)). Both ß-catenin loss- and gain-of-function (LOF and GOF) mutants displayed abnormal clefts in the perineal region and hypoplastic elongation of the URS. The mutants also displayed reduced cell proliferation in the URS mesenchyme. In addition, the ß-catenin GOF mutants displayed reduced apoptosis and subsequently increased apoptosis in the URS epithelium. This instability possibly resulted in reduced expression levels of differentiation markers, such as keratin 1 and filaggrin, in the perineal epithelia. The expression of bone morphogenetic protein (Bmp) genes, such as Bmp4 and Bmp7, was also ectopically induced in the epithelia of the URS in the ß-catenin GOF mutants. The expression of the Msx2 gene and phosphorylated-Smad1/5/8, possible readouts of Bmp signaling, was also increased in the mutants. Moreover, we introduced an additional mutation for a Bmp receptor gene: BmprIA. The Shh(CreERT2/+); ß-catenin(flox(ex3)/+); BmprIA(flox/-) mutants displayed partial restoration of URS elongation compared with the ß-catenin GOF mutants. These results indicate that some ARM phenotypes in the ß-catenin GOF mutants were caused by abnormal Bmp signaling. The current analysis revealed the close relation of endodermal ß-catenin signaling to the ARM phenotypes. These results are considered to shed light on the pathogenic mechanisms of human ARMs.

Delayed onset of systemic lupus erythematosus in a child with endothelial tubuloreticular inclusion.

We report here on an 11-year-old Japanese girl who was found to have proteinuria by routine mass screening urinalysis for school children, and who developed systemic lupus erythematosus (SLE) 21 months later. The initial renal biopsy, performed 3 months after the first visit to Tokyo Medical University Kasumigaura Hospital (TMUKH), revealed membranous glomerulonephritis. In an immunofluorescent study, IgG was the only positive immunoglobulin found. A "full-house" immunofluorescence glomerulopathy, well known as a predictive finding for lupus nephritis, was not detected. Endothelial tubuloreticular inclusions (ETI) were found by electron microscopy. Because the diagnosis of SLE was not established clinically and serologically, the patient was followed every 3 months without drugs. Her urinary findings returned to normal within 18 months. Three months after the last visit, she was sent to Tsukuba University Hospital (TUH) for fever, arthralgia, dyspnea and butterfly rash. She was diagnosed as having SLE, pleuritis, and pericarditis. Although she was treated with methylpredonisolone and oral prednisolone, she developed cardiac tamponade on the 12th day of admission during the course of pneumococcal septicemia. Finally, she was treated successfully with surgical procedures, antibiotics and oral prednisolone and was discharged. We conclude that ETI is a more significant early sign of SLE than "full-house" immmunofluorescence glomerulopathy, especially in pediatric cases.

C-reactive protein frequently localizes in the kidney in glomerular diseases.

AIM: In recent reports, C-reactive protein (CRP) has emerged as a component that may play important roles in atherogenesis. Based on the analogies set out in a previous report between focal-segmental sclerosis and atherosclerosis, we hypothesized that CRP contributes to the pathogenesis of glomerular diseases. To our knowledge, no immunohistochemical study of CRP localization in the kidneys has been previously reported. PATIENTS AND METHODS: In the present study, we investigated 106 kidney biopsy specimens from children with various types of glomerular diseases and minor glomerular abnormalities. Of the 106 cases, 74 were proliferative diseases, 17 were non-proliferative diseases, and 15 were minimal-change nephrotic syndrome (MCNS). Immunohistochemical staining was performed using monoclonal antibody to CRP. RESULTS: CRP immunoreactivity was found in 48 of 106 (45.3%) specimens. CRP deposition was encountered more often in patients with proliferative diseases (56.8%) than in those with non-proliferative diseases (23.5%) (p < 0.01). CRP deposition, most frequently observed along the capillary walls of glomeruli, was found in 33 of 46 (71.7%) cases with positive expression of CRP. CRP was also located in the peritubular capillary walls and small vessels in the interstitium in 13 of 46 cases (28.3%). CRP deposition was also found in 2 of 15 cases of MCNS. The two MCNS specimens showing positive CRP immunoreactivity were both from patients who had undergone cyclosporin therapy. CRP deposition was not shown in any cases treated with steroids or cyclophosphamide. The cases of patients who had undergone renal biopsies within 6 months after onset revealed a tendency toward positive CRP deposition. The clinical outcomes at the latest follow-up were quite similar between the groups of patients with and without CRP deposition. CONCLUSIONS: We surmise that circulating CRP may deposit at the site of endothelial injury, and may not be relevant to the progression of renal lesions.

Steroid-sensitive nephrotic syndrome associated with Kimura disease.

We report an 11-year-old Japanese boy with Kimura disease and associated nephrotic syndrome. Before the diagnosis of Kimura disease was established, the patient had three episodes of swelling on the left cheek with subsequent nephrotic syndrome. Steroids were effective for both conditions. However, both conditions recurred within months of discontinuation of steroids. For the fourth episode of swelling on the left cheek, cyclosporine (CsA) was used. The subcutaneous tumor responded to CsA and disappeared within a few days. There has been no subsequent relapse of the nephrotic syndrome to date.

Collaborative work to evaluate toxicity on male reproductive organs by repeated dose studies in rats 1). Effects of 2-weeks daily administration of estradiol benzoate.

As part of a collaborative project to assess whether a 2-weeks administration period is sufficient to detect testicular toxicity of various compounds, male rats were subcutaneously administered 0, 5, 20, 50 or 100 micrograms/kg of estradiol benzoate (E2B), a known testicular toxicant, daily for 2 or 4 weeks. After 4-weeks, suppression of body weight gain, increase in the weight of the adrenal gland, and gross changes such as decrease in size of the prostate and seminal vesicles, and increase in size of the adrenal gland were observed in the 5, 20, 50 and 100 micrograms/kg groups. On histopathological examination, degeneration/necrosis of Pachytene spermatocytes, atrophy of Leydig cells, mature spermatid retention (Lee, et al., 1993) at stages IX, X and XI, and atrophy of ducts of the epididymides were also observed in the 5, 20, 50 and 100 micrograms/kg groups. After 2-weeks, the same changes were also observed with 20, 50 and 100 micrograms/kg, but not 5 micrograms/kg. These results indicate that the toxic effects of E2B are detectable by administration for 2 weeks at an appropriate dose level.

[Renal glucosuria and membranous glomerulonephritis in chronic inflammatory demyelinating polyradiculoneuropathy: CIDP].

Glucosuria was detected in a 7-year-old boy by a routine school mass examination in April 1991. The diagnosis of renal glucosuria was made in the affiliated hospital of the University of Tsukuba. The patient developed muscle weakness and gait disturbance in February 1993. Spinal fluid examination revealed a protein level of 62 mg/dl and a cell count of 4/3. Under the diagnosis of Guillain-Barré syndrome, he was treated with i.v. immunoglobulin and oral prednisolone. Although the therapy somewhat improved the symptoms, his muscle strength had not fully recovered at the end of the treatment. In November 1995, the muscle weakness became worse; he could not go up stairs, nor stand upright on one leg. In April 1996, proteinuria was detected in a school mass examination. He was referred to the University Hospital of Tsukuba for a full renal study in March 1997. Renal biopsy revealed global sclerosis in 16 of 19 glomeruli with extensive interstitial fibrosis and mononuclear cell infiltration. A diagnosis of membranous glomerulonephritis was established based on the findings of spikes in PASM staining, weak IgG deposition in the glomerular capillary and subepithelial deposits by electron microscopic study. Additionally, pituitary growth hormone deficiency was found by endocrinological examination. The diagnosis of CIDP was established by fibulal neuron biopsy, which revealed neuronal degeneration and profound demyelinization. The clinical course of the present case was unlike that of the few reported cases of MGN associated with CIDP described in the literature. The initial renal symptom was glucosuria, which started 5 years prior to the onset of proteinuria. Second, glomerulosclerosis was more extensive than that seen in the literature. We surmise that chronic interstitial nephritis of insidious onset was followed by MGN which developed subsequently, probably at the time of the start of proteinuria.

Plasma lipoprotein (a) levels in children with minimal lesion nephrotic syndrome.

We studied the plasma lipoprotein (a)[Lp(a)] levels in 31 children with minimal lesion nephrotic syndrome (MLNS) in both stages of acute NS and remission. The mean Lp(a) levels in acute NS were significantly higher than those of the controls. The Lp(a) levels in remission were significantly lower than the Lp(a) levels in acute NS. In addition, the Lp(a) levels in remission were not significantly different from those of the controls. However, there were 5 patients whose Lp(a) levels remained higher than 30 mg/dl (the generally accepted limit for cardiovascular risk) after remission. Two of these 5 patients had Lp(a) levels greater than 40 mg/dl. In these patients apoprotein (a) [apo(a)] phenotypes were of lower molecular weight than those of the other 23 patients whose apo(a) phenotypes were examined. Additional episodes of relapse may put the patient with sustained elevated Lp(a) levels at significant risk for the development of cardiovascular disease in the long term.

Clinical significance of apolipoprotein (a) deposition in kidney diseases of children.

AIM AND METHOD: To address the clinical significance of lipoprotein (a) (Lp(a)) deposition in renal diseases of children, we examined renal localization of apolipoprotein (a) (apo(a)), which is the major apoprotein of Lp(a), using a new monoclonal antibody as a probe, and compared histological changes and clinical courses between the cases with and without apo(a) accumulation. Our study comprised 78 cases with various renal diseases. RESULTS: Of the 78 cases, 45 showed apo(a) deposition (group A) and the other 33 did not (group B). Nephrotic syndrome was similarly presented in groups A and B (46.7% vs 36.3%). Histological findings were analyzed in 62 proliferative and 16 non-proliferative original diseases separately. In the cases with proliferative diseases, severe histological changes were observed in group A more than in group B, severe proliferation (50.9% vs 26.1%: p < 0.01) and crescent formation (11.9% vs 5.1%: p < 0.01) were observed in group A over that of group B. However, the clinical status at the latest follow-up were quite similar, there was no difference of favorable (60.5% vs 62.5%) and unfavorable outcome (15.9% vs 16.7%) in groups A and B. In the cases with non-proliferative diseases, global sclerosis was more often encountered in group A than in group B (28.3% vs 6.5%). Group A carried poorer prognosis than group B in non-proliferative diseases. CONCLUSION: These results suggest that apo(a) deposits just passively follow the histological injury, and they do not always accelerate it.

Occurrence in Soybeans of a Novel Vitamin B6 Conjugate that Liberates Pyridoxine by ß-Glucosidase Action after Alkali Treatment.

A type of vitamin B6 conjugates (B6X), which liberates free vitamin B6 by alkaline and successive ß-glucosidase hydrolyses, is known to occur in rice bran and wheat bran. Conflicting experimental results, however, have been reported about the occurrence of B6X in soybeans. This study afforded evidence for B6X occuring in soybeans: certainly a highly purified B6X preparation from whole soybeans liberated pyridoxine when it was treated with alkali followed by ß-glucosidase hydrolysis, and 5'-O-(ß-D-glucopyranosyl)pyridoxine by alkali treatment alone. The B6X content varied with cultivars, of which a certain kind contained no B6X.

Abnormal myelination in a patient with ring chromosome 18.

We describe a Japanese boy with ring chromosome 18 in whom abnormal myelination was observed on magnetic resonance imaging. Cytogenetic investigation revealed 46, XY, r(18) (p11.2 q21.33). T2-weighted magnetic resonance imaging scan of the brain demonstrated high signal intensity consistent with abnormal myelination. Microsatellite marker analysis of DNA demonstrated only one copy of the myelin basic protein gene, derived from the mother. The present case indicates that a hemizygous state for the myelin protein gene may be related to the abnormal myelination.

Localization of the neuronal class III beta-tubulin isotype in foci of early neuritogenesis supports divergent neuroblastic differentiation potential in Wilms' tumors.

Wilms' tumors are embryonic neoplasms that have been proposed to originate from the metanephric blastema and are capable of divergent epithelial and mesenchymal differentiation. Neuroepithelial differentiation in these tumors remains controversial. The aim of this study was to examine the phenotypic profile of certain neuronal and glial antigenic determinants in a series of 21 Wilms' tumors. Immunohistochemical studies were performed by using monoclonal antibodies against the neuronal class III beta-tubulin isotype (beta III), the phosphorylated and phosphorylation-independent epitopes of neurofilament protein, and synaptophysin; antisera to gamma-enolase (neuron-specific enolase) glial fibrillary acidic protein, and S100 protein were also used. Foci of neoplastic cells with neurite-like processes that exhibited intense beta III staining were demonstrated in blastemalike areas of three of 21 tumors. In one case, Homer Wright rosettes (stained for beta III) were identified. Areas of abortive neuritic development were also labeled with antibodies to gamma-enolase. No reactivity was obtained in these foci for phosphorylated and phosphorylation-independent epitopes of neurofilament protein, synaptophysin, glial fibrillary acidic protein, and S100 protein. The remainder of the tumors (18 of 21) were negative with the panel of neural markers. Our results indicate that divergent neuroblastic differentiation, evidenced as early neoplastic neuritogenesis, may be present in the blastematous component of Wilms' tumor subsets.

Macroscopic hematuria in childhood IgA nephropathy.

The clinical presentation, initial laboratory and renal biopsy findings, and subsequent clinical course in 205 children with IgA nephropathy were studied retrospectively. The findings in the 119 patients with macroscopic hematuria and those in the 86 without macroscopic hematuria were compared. There were no differences with regard to sex distribution, age at onset, initial renal function, incidence of hypertension, degree of proteinuria and degree of mesangial proliferation. At the latest follow-up, 3% of the patients with macroscopic hematuria and 8% without macroscopic hematuria had developed chronic renal failure; 8% of the patients with macroscopic hematuria and 20% without had heavy proteinuria with or without hypertension (p less than 0.01); 41% of the patients with macroscopic hematuria and 24% without macroscopic hematuria had normal urine, blood pressure and GFR (p less than 0.05). The disease appears to follow a significantly more benign course in children with macroscopic hematuria than in those without macroscopic hematuria. These observations suggest some macroscopic hematuria-related differences in the natural history of childhood IgA nephropathy.

Henoch-Schoenlein nephritis and IgA nephropathy in children: a comparison of clinical course.

The clinical presentation, initial laboratory and renal biopsy findings, and subsequent clinical course were studied and compared in 128 children with Henoch-Schoenlein (HS) nephritis and in 206 children with IgA nephropathy. The clinical and pathological findings of the two conditions were similar. After a mean follow-up period of 5 years, 72 patients (56%) with HS nephritis and 67 (32%) with IgA nephropathy showed no demonstrable abnormality, 29 (23%) with HS nephritis and 103 (50%) with IgA nephropathy had minor urinary abnormalities, 7 (5%) with HS nephritis and 26 (13%) with IgA nephropathy had heavy proteinuria and/or hypertension, and 20 (16%) with HS nephritis and 10 (5%) with IgA nephropathy had developed chronic renal failure. A worse outcome was significantly associated with the more severe clinical presentations and more severe glomerular changes by light microscopy in HS nephritis, whereas there was no relationship between the severity of clinical presentation and glomerular changes and prognosis in IgA nephropathy. These findings suggest that HS nephritis is an acute disease and prognosis is associated with the severity of glomerular changes at onset, while IgA nephropathy is a chronic, slowly progressive glomerular disease.

Clinical course of immunoglobulin A nephropathy in children.

The clinical presentation, initial laboratory and renal biopsy findings, and subsequent clinical course of IgA nephropathy were studied retrospectively in 200 children, and findings in those with younger onset and older onset were compared. Eighty-three patients were 8 years of age or younger (group 1) and 117 were 9 years of age or older (group 2) at onset. There were no differences between the two groups with regard to sex, initial renal function, incidence of hypertension and macroscopic hematuria, degree of proteinuria, and pathologic findings. At the latest follow-up, two patients in group 1 and eight in group 2 had chronic renal failure, and five patients in group 1 and 21 in group 2 had heavy proteinuria with or without hypertension (P less than 0.01), whereas 36 (43%) patients in group 1 and 29 (25%) in group 2 had normal urine, blood pressure, and glomerular filtration rate (P less than 0.01); the disease followed a significantly more benign course in children with younger onset than in those with older onset. These observations suggest some age-related differences in the natural history of childhood IgA nephropathy.

Focal segmental glomerulosclerosis with and without nephrotic syndrome in children.

The clinical presentation, initial laboratory and renal biopsy findings, and course of focal segmental glomerulosclerosis (FSGS) were studied retrospectively in 57 children in order to compare findings in those with and without nephrotic syndrome and to establish factors of prognostic significance. All patients had proteinuria. Eleven patients were otherwise asymptomatic, and nephrotic syndrome did not develop (group 1); 14 patients had asymptomatic proteinuria, but nephrotic syndrome subsequently developed (group 2); 32 patients had nephrotic syndrome (group 3). There were no differences between these three groups with regard to sex, age, initial renal function, incidence of hypertension and hematuria, and pathologic findings. At the latest follow-up, five group 1 patients, six in group 2, and 14 in group 3 had chronic renal failure; the incidence was similar for those with asymptomatic proteinuria and those with nephrotic syndrome. The location of the sclerosis within the glomerulus proved to have prognostic significance. All 12 patients with peripheral FSGS maintained normal renal function, whereas in 25 of the 44 with hilar FSGS chronic renal failure developed.

Glucose metabolism in pediatric renal transplant recipients: relation to insulin receptors of erythrocytes.

We studied the oral glucose tolerance test (O-GTT) of 13 kidney transplant recipients and compared the results with the insulin binding characteristics of their own erythrocytes. They had mild renal insufficiency with significant increase of serum creatinine concentrations. Body weights were slightly but significantly elevated compared to the controls. All were receiving small doses of prednisone (0.2-0.3 mg/kg/day). Ten of the 13 patients had normal O-GTT and normal binding of 125I-insulin, while the remaining 3 patients showed abnormal O-GTT and significantly reduced maximum binding of 125I-insulin to erythrocytes. Basal insulin concentration and response to O-GTT were significantly elevated in the patients, regardless of O-GTT being normal or abnormal. It is concluded that transplant recipients have an impaired insulin action due to a post-receptor stage abnormality in glucose metabolism which is due perhaps to mild renal insufficiency, mild obesity and prolonged administration of the small dosage of prednisone.