Melamine Nephrotoxicity is Mediated by Hyperuricemia / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>We tested whether melamine nephrotoxicity was exacerbated by urate (a typical component of renal stones in humans) in rats with hyperuricemiainduced by the uricase inhibitor, potassium oxonate (Oxo).</p><p><b>METHODS</b>Rats were exposed to melamine or Oxo alone or combinations of melamine (200-400 mg/kg) and Oxo (200-600 mg/kg) for 3 consecutive days. Kidney injury was evaluated by renal biochemical functions, histomorphology, and lipid peroxidation. Kidney crystals were analyzed for their composition.</p><p><b>RESULTS</b>Nephrotoxicity was minimal in animals administered melamine or Oxo alone, but it was demonstrable in animals administered at least 800 mg/kg of the two compounds combined. All rats in the 400+600 (melamine+Oxo) and 400+400 mg/kg groups and 4 out of 6 in the 200+600 mg/kg group died within 3 days; no rat died in the 200+400 or 200+200 mg/kg group. Dose-dependent renal damage resembling clinical findings in affected patients was observed in rats administered the two compounds. Crystal composition determination revealed the existence of melamine and uric acid in the affected kidneys, resembling human stones.</p><p><b>CONCLUSION</b>Our findings suggest that uric acid plays a key role in melamine-related kidney injury in humans. Future studies should consider uric acid together with melamine when examining adverse effects in humans.</p>

Clinical value of wireless capsule endoscopy in diagnosis of small bowel disease in children / 中华儿科杂志

<p><b>OBJECTIVE</b>The pathological change of small bowel is difficult to examine because it is anatomically unique. The development of wireless capsule endoscopy provides an unique opportunity to visualize the entire small bowel in a minimally invasive manner. The aim of this study was to assess the safety and clinical value of wireless capsule endoscopy in children.</p><p><b>METHODS</b>During the last 4 years (June, 2004-June, 2008), 46 times of wireless capsule endoscopy were performed in 43 patients with suspected small bowel disease, including obscure gastrointestinal bleeding (n = 11), recurrent abdominal pain (n = 20), chronic diarrhea (n = 9), protein losing enteropathy (n = 2), recurrent vomiting (n = 1). Of the 43 cases, 28 were male and 15 were female, the age ranged from 6 to 18 years, 8 of these cases were < 10 years old. The weight of the patients ranged between 15 kg and 60 kg. The average time of capsule passing through the stomach and the small intestine, the tolerance to and complication of wireless capsule endoscopy in patients, the image quality of capsule endoscopy, and the cleanliness of small intestine after fasting for 8 hours were observed and recorded.</p><p><b>RESULT</b>All the patients could easily swallow the capsule and had good tolerance. The overall success rate was 94% (43/46). The median time of capsule passing through the stomach and small intestine was 73 min (range, 3 - 600 min) and 246 min (range, 73 - 413 min), respectively. The diagnostic yield of pathological change in small intestine was 90% (37/41), and the diagnostic accordance rate was 84% (31/37). Based on the wireless capsule endoscopy, diagnostic findings included Crohn's diseases (15), lymph follicular hyperplasia (4), nonspecific enteritis (4), vascular malformations (3), small bowel tumour (2), primary intestinal lymphangiectasia (2), gastrointestinal motility disorders (2), Meckel's diverticulum (1), angioma (1), small intestinal worm disease (1), duodenal ulcer (1), and polyposis syndromes (1). The capsule of 1 patient remained in the stomach. The cleanliness of small intestine after 8 hours fasting was good. And the capsule endoscopy can show high quality small intestine image.</p><p><b>CONCLUSION</b>Wireless capsule endoscopy is a noninvasive, safe and useful tool for the investigation of the small intestine in children, especially for obscure gastrointestinal bleeding and Crohn's disease.</p>

Diagnosis and treatment of Crohn's disease in children: 10 years' clinical experience / 中华儿科杂志

<p><b>OBJECTIVE</b>To enhance our understanding of pediatric Crohn's disease and improve diagnostic accuracy and therapeutic efficacy by characterizing the clinical picture and reviewing 10 years' clinical experience in diagnosis and treatment.</p><p><b>METHODS</b>Nine cases with active Crohn's disease diagnosed between 1996 and 2005, including 8 males and 1 female, aged 6 - 13 years, were reviewed. Clinical, radiologic, endoscopic and histological data as well as therapeutic results were analized.</p><p><b>RESULTS</b>The mean interval from the onset of symptoms to the diagnosis was 10 months. The sites of involvement were both the small intestine and colon in 6, small intestine only in 3. Abdominal pain and diarrhea were the two most common gastrointestinal symptoms. The main extraintestinal manifestations were weight loss in 7, hypoalbuminemia in 5, mild anemia in 5, fever in 4 and hypocalcemia in 2. All the patients had undergone colonoscopy, and the findings included ulcerations, segmental lesions, cobblestone appearance, pseudopolyps and perianal abnormalities. Capsule endoscopic examination in one patient demonstrated the segmental distribution with typical longitudinal cleft-like ulcers and cobblestone appearance. Gastrointestinal barium meal X-ray examination was performed in 7 patients, the main findings were segmental strictures and abnormal mucosa. Histological examination of biopsy specimens mainly showed nonspecific chronic inflammation. Non-caseating granulomas were identifiable in 2 cases. Although there were many macroscopic and microscopic features supporting the diagnosis of Crohn's disease, no epithelioid granuloma could be found in surgical specimens of two patients. Treatment was given up by parents of 2 patients after the diagnosis was established. All the other 7 patients were treated with 5-acetylsalicylic acid, antibiotics and nutritional support during the acute phase. Corticosteroids were used in two patients. Long-term remission was achieved and maintained in 3 children, and in one of them medication could be discontinued and had no signs of disease activity at the end of the follow-up.</p><p><b>CONCLUSIONS</b>Children and adolescents presenting with Crohn's disease commonly have weight loss and nutritional impairment, which may provide clues to the diagnosis. Appropriate formulation and higher dosage of 5-acetylsalicylic acid [30-50 mg/(kg x d)] may be effective in inducing and maintaining remission in pediatric Crohn's disease.</p>