Zhen Zhen Li

Expression of renal aquaporins is down-regulated in children with congenital hydronephrosis

Abstract Objective. This study investigated mRNA and protein expression of four renal aquaporin isoforms [AQP1, 2, 3 and 4 (AQP1–4)] in congenital hydronephrotic kidneys (HK) due to pelviureteral junction obstruction and normal control kidneys. Material and methods. The expression of AQP1–4 was evaluated in 22 children (15 boys, seven girls, aged 58.9±54.3 months) using semi-quantitative reverse transcriptase–polymerase chain reaction (RT-PCR) techniques, immunoblotting and immunohistochemistry. Hydronephrosis was graded by ultrasound according to the Society for Fetal Urology. Results. Both RT-PCR and immunoblotting showed significantly reduced mRNA and protein expression of AQP1–4 in grade IV compared with those in grade III HK and controls. Sequencing demonstrated 99% homology of AQP1–4 with those in GenBank. Positive immunoreactivity of AQP1 was found in plasma membranes of the proximal tubule, thin descending limb of Henle and descending vasa recta; AQP2 in the apical membrane of collecting duct principal cells; and AQP3 and 4 in the basolateral membrane of the same cells. In kidneys with grade IV hydronephrosis there was reduction in the protein abundance of all four AQP isoforms which was more pronounced compared with the protein abundance seen in kidneys with grade III hydronephrosis and control kidneys. Conclusion. The expression of AQP1–4 mRNA and protein abundance is reduced in proportion with the degree of hydronephrosis graded by ultrasound in human congenital HK.

The effect of familial aggregation on the children with primary nocturnal enuresis

To evaluate the effect of familial aggregation on the children with PNE by evaluating nocturnal urine output, bladder, and arouse function.

Early alteration of urinary exosomal aquaporin 1 and transforming growth factor β1 after release of unilateral pelviureteral junction obstruction

BACKGROUND/PURPOSE Down-regulation of aquaporin 1 (AQP1) and up-regulation of transforming growth factor β(1) (TGF-β(1)) in the renal parenchyma have been demonstrated in children who underwent pyeloplasty for pelviureteral junction obstruction. However, no information about urinary exosomal AQP1 and TGF-β(1) during postobstructive polyuria in children with congenital unilateral hydronephrosis is available. The aim of the present study is to evaluate the urine concentration of exosomal AQP1 and TGF-β(1) on the first and the second day after surgery in children who underwent pyeloplasty. METHODS Twenty-two patients (age, 36.2 ± 17.1 months) with unilateral pelviureteral junction obstruction were examined in the study. For the first 2 days after the operation, the urine was collected separately from pyelostomy draining only from the postobstructed kidney and from the bladder catheter draining mostly from the contralateral kidney, which was used as an internal control. Urinary output, urinary osmolality, sodium, β(2)-microglobulin (β(2)-MG), and creatinine, as well as urinary exosomal AQP1 and TGF-β(1) excretion, were tested in each sample. RESULTS After pyeloplasty, a significantly decreased urinary excretion of exosomal AQP1 (≈ 64%) was found in the postobstructed kidney. The patients developed polyuria (807 ± 216 mL/24 h vs 484 ± 144 mL/24 h at day 1, 1021 ± 348 mL/24 h vs 603 ± 228 mL/24 h at day 2; P < .01) and reduced urine osmolality (115 ± 44 mOsm/kg vs 282 ± 61 mOsm/kg at day 1, 139 ± 39 vs 303 ± 46 mOsm/kg at day 2; P < .01) that persisted for 48 hours. In parallel, urinary TGF-β(1) and β(2)-MG (normalized for creatinine) from the postobstructed kidney were significantly higher compared with the contralateral kidney. The urine output and urinary sodium concentration from the postobstructed kidney elevated significantly on the second day after the release of obstruction compared with those on the first day. The contralateral kidney also showed same trends. CONCLUSIONS The down-regulation of urinary exosomal AQP1 in the postobstructed kidney may account for the polyuria, hypotonic urine, and elevated urinary β(2)-MG. The urinary TGF-β(1) level locally increased in the postobstructed kidney may be involved in renal AQP1 down-regulation.

Melamine-Related Urinary Stones in 195 Infants and Young Children: Clinical Features within 2 Years of Follow-Up

Objective: To summarize the clinical features and follow-up, the effects of melamine-tainted milk powder (MMP) consumption on kidney and body growth in children who suffered from melamine-related urinary stones (MUS) 2 years earlier were checked. Measurements: Body height and weight, kidney and bladder morphology monitored by ultrasound, urinalysis and renal function were recorded. Plain abdominal radiography was performed for differential diagnosis. The first follow-up was carried out at 15 months and the second 2 years later for patients who showed any abnormality at the first follow-up. Two hundred age- and gender-matched cohorts were included. Results: All cases received conservative treatment in hospital. Fifteen months of follow-up was successfully carried out in 167 cases. 91 children had residual MUS at the time of discharge, 58 MUS disappeared completely, 25 dissolved partially, 1 increased in size, and 7 did not change. At 2 years of follow-up, the residual stones all disappeared except for 1 case; the patient who showed a delayed development with regard to height caught up at 24 months of follow-up. Conclusions: Conservative treatment shows a high effectiveness in cases with residual MUS. Consumption of MMP with timely treatment did not demonstrate an evident impact on kidney and bladder although body height is slightly affected in a few cases.

Risk factors of nocturia (two or more voids per night) in Chinese people older than 40 years

To explore the risk factors of nocturia in Chinese inhabitants aged ≥40 years.