Deposition of calcium salts in a case of pulmonary zygomycosis: histopathologic and chemical findings

We report a case of pulmonary zygomycosis associated with unusual deposition of calcium salt crystals. The patient was a 75-year-old female who had onset of cough and shortness of breath. She was treated for community-acquired pneumonia but died despite intensive therapy. Postmortem examination revealed diffuse alveolar damage and multifocal necrotizing pneumonia associated with herpes simplex infection and invasive zygomycosis. Birefringent particles were seen associated with fungal elements in the lung parenchyma, within bronchial cartilage, and in blood vessel walls. By infrared spectroscopy, the birefringent particles in the pulmonary parenchyma and within bronchial cartilage had spectral characteristics of calcium oxalate dihydrate and calcium oxalate monohydrate, respectively. The birefringent crystals within vascular walls were identified as calcium carbonate. This case documents the chemical composition and location of 3 different calcium salt crystals in pulmonary zygomycosis. It also shows that among pulmonary fungal infections, calcium oxalate deposition is not restricted to aspergillosis.     

Oxalate Metabolism after Intestinal Bypass Operations

Hyperoxaluria and kidney stones are frequent following intestinal bypass operations. The urinary oxalate excretion was studied for 10-13 days during enteral and parenteral nutrition in six patients operated on because of massive obesity with a jejunoileostomy. The oxalate excretion in urine was higher than normal in all patients on normal diet. The excretion decreased on low-oxalate diet. Further decrease was observed during total parenteral nutrition (TPN). The oxalate excretion was stabilized at a low level within 48 h after the start of TPN and was unchanged during the rest of the study. This included a period of 2 days when a load of the oxalate precursor glycine (10 and 20 g) was given parenterally to five patients, resulting in increased serum glycine concentration. A slight decrease in oxalate excretion was found when the amino acid part (Vamin® with 10% glucose) of the TPN solution was given enterally instead of parenterally in two patients. This study has indicated that the main reason for hyperoxaluria in patients with intestinal bypass operations is hyper-absorption of dietary oxalate. It seems likely that these patients have a normal endogenous oxalate production.     

Calcium isolation from large-volume human urine samples for 41Ca analysis by accelerator mass spectrometry

Calcium oxalate precipitation is the first step in preparation of biological samples for ⁴¹Ca analysis by accelerator mass spectrometry. A simplified protocol for large-volume human urine samples was characterized, with statistically significant increases in ion current and decreases in interference. This large-volume assay minimizes cost and effort and maximizes time after ⁴¹Ca administration during which human samples, collected over a lifetime, provide ⁴¹Ca:Ca ratios that are significantly above background.     

高效液相色谱法同时测定健康人尿液中草酸和枸橼酸的含量

目的建立HPLC同时测定人尿草酸和枸橼酸含量的方法。方法采用Agilent SB C18(250mm×4.6mm,5μm)色谱柱;Agilent zorbax extend-C18(4.6mm×12.5mm,5μm)为保护柱;以0.018mol.L-1磷酸二氢钾(含0.010mol.L-1四丁基硫酸氢铵和2.69×10-5mol/L EDTA,pH2.4~2.5)为流动相;检测波长210nm;流速1.5mL.m in-1;柱温25℃;进样量20μL;以50mg/mL磺基水杨酸沉淀尿蛋白。结果草酸最低检测限为0.4μg.mL-1。线性范围为1.563~100μg.mL-1,平均回收率为97.66%,日内及日间精密度RSD<13.50%。枸橼酸最低检测限为0.8μg.mL-1。线性范围为3.125~200μg.mL-1,平均回收率为97.71%,日内及日间精密度RSD<8.25%。结论该方法简便,灵敏度高,重复性好,可用于尿路草酸钙结石成因的研究。     

A Comparative Study on Several Models of Experimental Renal Calcium Oxalate Stones Formation in Rats

In order to compare the effects of several experimental renal calcium oxalate stones formation models in rats and to find a simple and convenient model with significant effect of calcium oxalate crystals deposition in the kidney, several rat models of renal calcium oxalate stones formation were induced by some crystal-inducing drugs (CID) including ethylene glycol (EG), ammonium chloride (AC), vitamin D3 [1α(OH)VitD3, alfacalcidol], calcium gluconate, ammonium oxalate, gen-tamicin sulfate, L-hydroxyproline. The rats were fed with drugs given singly or unitedly. At the end of experiment, 24-h urines were collected and the serum creatinine (Cr), blood urea nitrogen (BUN), the extents of calcium oxalate crystal deposition in the renal tissue, urinary calcium and oxalate ex-cretion were measured. The serum Cr levels in the stone-forming groups were significantly higher than those in the control group except for the group EG L-hydroxyproline, group calcium gluconate and group oxalate. Blood BUN concentration was significantly higher in rats fed with CID than that in control group except for group EG L-hydroxyproline and group ammonium oxalate plus calcium gluconate. In the group of rats administered with EG plus Vitamin D3, the deposition of calcium ox-alate crystal in the renal tissue and urinary calcium excretion were significantly greater than other model groups. The effect of the model induced by EG plus AC was similar to that in the group in-duced by EG plus Vitamin D3. EG plus Vitamin D3 or EG plus AC could stably and significantly in-duced the rat model of renal calcium oxalate stones formation.     

离子色谱法测定蔬菜的草酸含量

本文叙述一种使用离子色谱技术测定蔬菜中草酸含量的新方法。该法只需简单的样品制备:将样品捣成匀浆,用盐酸酸化,在沸水中煮一小时,过滤,用去离子水按需要稀释,再通过0.2μm孔径的微孔滤膜,就能直接注入离子色谱仪分析。每分析一个样品仅需20分钟。最低检出限为0.1ppm(1.1μmol/L),线性范围1～1000ppm,批内和批间变异系数分别为2.7％和3.2％,平均回收率99.6％。本方法简便、快速、准确,可用于蔬菜中草酸含量的测定。     

Influence of gender and age on calcium oxalate crystal growth inhibition by urine from relatives of stone forming patients

PURPOSE: We define the relationships between urine inhibition of calcium oxalate crystal growth and age, gender, urine chemistries and stone formation among relatives of calcium stone forming patients. MATERIALS AND METHODS: We collected 24-hour urine samples from 366 first degree relatives of calcium stone formers. Calcium oxalate crystal growth inhibition was studied using a constant amount of dialyzed urine protein in a seeded crystallization system. Standard stone risk measurements were also performed on the urine, including supersaturation for calcium oxalate, calcium phosphate and uric acid. RESULTS: By multivariate analysis crystal growth inhibition is strongly inversely related to the amount of protein excreted per day, and the age of the subject. When corrected for protein excretion and age, urine proteins from nonstone forming male subjects inhibited crystal growth more strongly than those from corresponding female subjects. Among stone formers the sex difference was not present. CONCLUSIONS: Inhibition of calcium oxalate crystal growth is influenced by a complex combination of gender, age, stone formation and assay conditions. The effect of daily protein excretion is most likely a consequence of using a fixed amount of urine protein per assay. The influence of age is significant and unexplained, with the urine of young people (less than 20 years) demonstrating a vigorous ability to inhibit crystallization. In addition, the urine of nonstone forming male relatives appears to have a greater ability to inhibit crystallization than that of nonstone forming female relatives. Further use of this assay in clinical investigations must take age and gender into proper account.     

泽泻活性成分对肾结石模型大鼠bikunin表达的影响

目的研究中药泽泻活性成分对结石模型大鼠肾结石形成和bikunin表达的影响,以探讨泽泻防治草酸钙尿石症的作用机理.方法分离提取泽泻的化学活性成分,制作大鼠肾草酸钙结石模型.将Wistar大鼠随机分成对照组、结石模型组、泽泻组,采用半定量逆转录聚合酶链反应检测大鼠肾组织bikunin mRNA的表达水平、镜下观察肾组织草酸钙晶体分布,同时检测大鼠血生化、肾钙含量、24h尿钙和尿草酸的分泌量.结果①泽泻组大鼠肾组织草酸钙晶体分布、血生化等指标均明显低于结石组.②泽泻组和成石组大鼠肾组织bikunin的相对表达水平分别为(0.528±0.170,0.713±0.250)、肾钙含量分别为[(4.70±0.08)mg/g,(9.49±0.45)mg/g]、24h尿钙分泌量分别为[(37.23±1.84)μmol,(61.49±2.06)μmol],各组间差异均有显著性意义(P＜0.05).结论泽泻活性成分能下调bikunin在结石大鼠肾组织的表达,减少肾组织草酸钙晶体的形成,从而抑制大鼠肾结石形成.     

溶石颗粒剂对结石模型大鼠肾骨桥蛋白表达的影响

目的：通过测定用药前后肾脏骨桥蛋白(osteopontin,OPN)的变化,来阐明民间验方溶石颗粒剂防治肾结石的作用机制。方法：采用乙二醇、氯化胺法致大鼠肾结石,同时每天1次ig给予溶石颗粒剂5.8,11.6,17.4 g·kg^-1,实验全程21 d。每7 d作以下测定：尿标本以EDTA法测定钙浓度,比色法测定草酸浓度；肾组织HE染色,以免疫组化法检测大鼠肾骨桥蛋白的表达。结果：模型组大鼠肾OPN的表达明显增加,与溶剂对照组相比P<0.01,其中21 d模型组OPN的表达最高,OPN的表达为溶剂对照组的1.4倍（0.281 3/0.201 8）；溶石颗粒剂各剂量组均能明显抑制大鼠肾结石模型OPN的表达（P<0.05）,且呈现明显的量效关系；溶石颗粒剂各剂量组能减轻大鼠肾脏草酸钙结晶程度,显著降低大鼠尿钙和草酸浓度(P<0.01)。结论：溶石颗粒剂可以抑制大鼠肾结石模型中OPN的表达。     

Characterization of Tamm-Horsfall protein in a rat nephrolithiasis model

PURPOSE: The role of Tamm-Horsfall protein in calcium oxalate stone formation is controversial. It is unclear whether Tamm-Horsfall protein has a role in crystallization. If it does, does it act as an inhibitor or promoter of crystallization? To elucidate the nature of its involvement we characterized Tamm-Horsfall protein in a rat model of calcium oxalate nephrolithiasis by in vivo and in vitro techniques. MATERIALS AND METHODS: Calcium oxalate nephrolithiasis was induced in male Sprague-Dawley rats. The amino acid and carbohydrate composition of Tamm-Horsfall protein from normal rats and those with nephrolithiasis was determined. The Tamm-Horsfall protein gene and protein expression in the kidneys were examined by in situ hybridization and immunohistochemistry. Furthermore, the interaction of Tamm-Horsfall protein and calcium oxalate crystals was assessed by an in vitro crystal aggregation assay. RESULTS: Tamm-Horsfall protein from rats with nephrolithiasis was biochemically similar to that from normal rats. Although Tamm-Horsfall protein was associated with crystal deposits in the renal papillae of rats with nephrolithiasis, Tamm-Horsfall protein messenger RNA expression in the kidneys remained unchanged. In each group Tamm-Horsfall protein inhibited calcium oxalate crystal aggregation by 47%, indicating no change in functional capabilities. CONCLUSIONS: The results of this study indicate that urinary excretion, and the biochemical nature and functional capabilities of Tamm-Horsfall protein remain unchanged during experimental calcium oxalate nephrolithiasis. Although staining for Tamm-Horsfall protein was evident in the papillae of rats with nephrolithiasis, the site of Tamm-Horsfall protein synthesis remained cells of the thick ascending limbs of the loop of Henle.