Biomedical subjects

Takeshi Yanagihara

Publications and source records attributed to Takeshi Yanagihara.

3 recordsLinked to original sources

PubMed2005

Long-term follow-up of diffuse membranoproliferative glomerulonephritis type I.

In Japan, the school urinary screening system facilitates early detection and treatment of membranoproliferative glomerulonephritis (MPGN) in childhood. The present study investigated the long-term prognosis in 19 children with diffuse MPGN type I who received steroid therapy. Before signs of glomerulonephritis were confirmed, all patients displayed abnormal urinalysis results, predominantly through school urinary screening. Treatment comprised a regimen of alternate-day prednisolone after steroid pulse or cyclophosphamide therapy, and follow-up was continued for 10-24 years. Excluding 1 patient on short-term therapy, 18 patients received long-term alternate-day prednisolone therapy for 4-12 years. Treatment was discontinued when amelioration was confirmed on renal biopsy. As of the last observation, urinary abnormalities and hypocomplementemia had disappeared in 15 patients, while mild proteinuria without hypocomplementemia remained in 4 patients. No patients required hemodialysis. Moreover, no severe adverse effects attributable to treatment were identified other than mild short stature. Early detection and therapy using pulse methylprednisolone followed by alternate-day prednisolone was thus confirmed as safe and useful for treating diffuse MPGN type I.

Adolescent↗

PubMed2004

Age-dependent decrease of polymeric Ig receptor expression and IgA elevation in ddY mice: a possible cause of IgA nephropathy.

Individual animals in the closed colony population of ddY mice were analyzed to clarify the major cause of age-dependent elevation of serum IgA and the appearance of human IgA nephropathy (IgAN)-like symptoms. Based on the serum IgA levels, the mice were classified into two subgroups. One was a high serum IgA group with some manifestations of IgAN through aging (ddY(High)), and the other was a normal serum IgA group without IgAN (ddY(Norm)). The ratio of urinary IgA to serum IgA was significantly reduced in ddY(High) mice, suggesting an impaired IgA clearance via secretion through the epithelial barrier. The actual clearance rate of the intravenously injected dimeric IgA in ddY(High) mice was found to be slower than that in ddY(Norm) mice. Furthermore, we found that the polymeric Ig receptors (pIgRs) that mediate transcytosis of IgA were poorly expressed in the glomeruli as well as in the intestine of ddY(High) mice, whereas the pIgRs were more abundantly expressed in ddY(Norm) mice. In addition, the comparative study using polymerase chain reaction showed that decreased pIgR expression occurred at the transcriptional level in the ddY(High) population. Taken together, these results suggest that a systemic defect in pIgR expression may result in impaired IgA secretion and accumulation of IgA in the serum of ddY(High) mice. The age-dependent changes of pIgR expression in the dimeric IgA secretion sites of ddY(High) mice suggest a possible cause for the elevation of serum IgA level and the pathogenesis of IgAN-like disease.

Aging↗

PubMed2003

Ultrasound screening for renal and urinary tract anomalies in healthy infants.

BACKGROUND: Nearly 30% of childhood cases of chronic renal failure in Japan are attributed to congenital anomalies of the kidney and urinary tract (CAKUT), and the number is increasing. Urine screening at school facilitates early diagnosis and treatment of glomerulonephritis, but early screening for anomalies is currently not in practice. The authors evaluated the value of early abdominal ultrasonography screening in 1-month-old infants. METHODS: The following characteristics of kidneys were assessed: presence versus absence, size, symmetry of size, position, separation of the central echo complex (CEC), abnormal echogenicity, and other abnormal findings. The bladder and ureter were checked for abnormalities in bladder shape and wall, as well as retrovesical ureteral dilation. Criteria for abnormalities included kidney length of or=60 mm; a difference in length of left and right kidneys of 10 mm or more; and CEC separation of Society for Fetal Urology (SFU) grade 2 or higher. RESULTS: Beginning in April 1994 and continuing until September 2001, screening of 5700 1-month-old infants yielded 198 positive cases (3.5%) of CAKUT. Most frequent was abnormal CEC separation (approximately 60% of all abnormalities), followed by abnormal renal size or size asymmetry (30%). Further investigation yielded a specific diagnosis in 32 cases (0.6%) of all subjects. Most prevalent was obstructive uropathy (15 cases); 8 children underwent surgery. Small kidneys and vesicoureteral reflux were next in frequency. CONCLUSIONS: Ultrasonograpy was effective for early detection of renal and urinary tract anomalies. Ultrasound screening in early infancy may permit early treatment, that can prevent renal dysfunction.

Child↗