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Although metabolic syndrome and its individual components have been associated with kidney stone disease, whether the clustering of metabolic syndrome traits increases the severity of kidney stone disease has not been examined in a large-scale study.Cross-sectional analysis.Data were obtained from 30,448 patients enrolled in the 6th Nationwide Survey on Urolithiasis in Japan conducted in 2005. Patients with lower urinary tract stones, struvite stones, cystine stones, or hyperparathyroidism and those younger than 15 years were excluded.Number of metabolic syndrome traits (obesity [body mass index ≥25 kg/m(2)], diabetes, hypertension, and dyslipidemia).Severe form of kidney stone disease, defined as recurrent and/or multiple stones, and abnormalities in urine constituents (hypercalciuria, hyperuricosuria, hyperoxaluria, and hypocitraturia).11,555 patients were included in the final analyses. Proportions of patients with recurrent and/or multiple stones were 57.7%, 61.7%, 65.2%, 69.3%, and 73.3% with 0, 1, 2, 3, and 4 metabolic syndrome traits, respectively (P0.001). There was a significant and stepwise increase in the odds of recurrent and/or multiple stones after adjustment for age and sex. In patients with 4 metabolic syndrome traits, the odds was 1.8-fold greater compared with patients with 0 traits (OR, 1.78; 95% CI, 1.22-2.66). In addition, the presence of metabolic syndrome traits was associated with significantly increased odds of having hypercalciuria, hyperuricosuria, hyperoxaluria, and hypocitraturia after adjustment for age and sex.Cross-sectional design, absence of dietary data, ill-defined diagnostic criteria for metabolic syndrome traits, and missing data for the majority of participants.Metabolic syndrome trait clustering is associated with greater severity of kidney stone disease; increased urinary calcium, uric acid, and oxalate excretion; and decreased urinary citrate excretion. These results suggest that kidney stone disease should be regarded as a systemic disorder linked to metabolic syndrome.

OBJECTIVE To examine the responses of renal fibroblasts to high oxalate (Ox) and calcium Ox (CaOx) crystals, as the latter are found in the renal interstitium of patients with primary or enteric hyperoxaluria, and in animals with experimental CaOx nephrolithiasis, and are associated with tubulointerstitial inflammation (TI). TI might begin with the production of chemoattractants by the renal epithelial cells exposed to high Ox and/or CaOx crystals; as Ox levels are also high in the renal interstitium and crystal deposition in nephrolithiasis might start in the interstitium, we hypothesized that renal fibroblasts might also be involved in the development of TI. MATERIALS AND METHODS We exposed renal fibroblast cells of line NRK 49F in vitro to Ox ions (500 µmol/L) or CaOx monohydrate crystals (67 µg/cm2). We assessed the production of osteopontin and monocyte chemoattractant protein-1 (MCP-1), and expression of their mRNA, in the cells. We also determined the cellular malondialdehyde content as a marker of reactive oxygen species (ROS)-induced lipid peroxidation, and Trypan blue staining and the release of lactate dehydrogenase as markers of injury. RESULTS Similar to renal epithelial cells, renal fibroblasts were stimulated by exposure to Ox and CaOx crystals. They showed signs of injury and ROS-induced lipid peroxidation. The mRNA expression and production of osteopontin and MCP-1 increased significantly. CONCLUSIONS These results indicate that fibroblasts respond to high Ox and CaOx crystals by up-regulating specific pathways producing pro-inflammatory conditions. Migration of monocytes/macrophages to sites of interstitial crystal deposits can lead to localized interstitial inflammation and fibrosis.

Maxacalcitol, the 22-oxa-derivative of 1α,25-dihydroxyvitamin D3 and used currently as an antihyperparathyroidism and antipsoriatic drug, has been synthesized in seven chemical steps from 1α-hydroxydehydroepiandrosterone on the basis of our previously developed route. The present synthesis allows the production of the protected form of the penultimate intermediate in 26% overall yield in a kilogram scale reaction employing neither difficult reaction conditions nor chromatographic purification, having overcome all the difficulties involved in the previous route.

PURPOSE We examined whether there would be any inhibitive effect to the crystal formation in ethylene glycol treated rat kidney by angiotensin II type I receptor blocker (candesartan). METHODS We divided 10-weeks-old male Sprague-Dawley rats into 4 groups. In these groups, rats were given tap water (group A), 1.0% ethylene glycol (group B), 1.0% ethylene glycol and 20 microg/ml candesartan (group C), 20 microg/ml candesartan (group D) for 4 weeks. Immunohistochemical studies of a renal tissue was performed by ED1 antibody and the osteopontin antibody, the transcription of renin, angiotensin converting enzyme, angiotensin II and osteopontin mRNA in whole kidney was determined using real time PCR and malondialdehyde level was measured. Renal tissue was evaluated using H.E. stain for counting the calcium deposit in the renal tubules. Calcium concentrations in whole kidney were measured with an atomic absorption spectrophotometer. RESULTS Although there is no significant difference urinary oxalate and calcium levels compared with group B and C, group C showed fewer the numbers of calcium deposit in the tubules and decreased the amount of calcium contained in the whole kidney, ED1 positive cells, osteopontine mRNA expression and malondialdehyde level. CONCLUSION These results suggest that candesartan inhibited superfluously induced osteopontin in the whole kidney by ethylene glycol and crystal formation was also related decreased.

Objective: We evaluated whether osteopontin (OPN) and other proteins with the RGD sequence as in OPN (RGD family proteins) that are present in renal tubular cells (fibronectin [FN], Tamm–Horsfall glycoprotein [THP], vitronectin [VN], and laminin [LN]) inhibit the aggregation and growth of calcium oxalate (CaOx) crystals by a novel seed crystal method using collagen granules (CG) with and without OPN adhered on the surface. We also evaluated the effect of solid phase OPN, FN and THP in which the relationship between their proteins and CaOx crystallization was reported. Moreover, the state and time-course changes in CaOx crystals adhered to CG were observed under scanning electron microscopy (SEM). Methods: The inhibitory activity (IA) on the aggregation and growth of CaOx crystals was measured in vitro by the conventional seed crystal method using isotopes. In this study, the following nine samples were used: OPN alone; FN alone; THP alone; VN alone; LN alone; CG alone; and CG with OPN, FN, or THP adhered on the surface (OPN/FN/THP-immobilized CG). In addition, the state and time-course changes in CaOx crystals adhered to CG were evaluated by SEM. Results: Using the conventional seed crystal method, the following values of IA were obtained: 91.7% (37.5μg/ml) for OPN, 5.0% (100μg/ml) for FN, 2.0% (100μg/ml) for THP, 3.0% (100μg/ml) for VN, and 1.0% (100μg/ml) for LN. However, the value of IA obtained by our seed crystal method using CG was 92.1% (180cm 2 /5ml PBS) when CG alone was used. Although the value of IA was decreased by 33.6% when OPN-immobilized CG was used, it did not significantly change when FN/THP-immobilized CG was used. When CG alone was used, the evaluation of CaOx crystallization by SEM demonstrated mild adherence and aggregation of CaOx crystal suspension (seed crystals) on the CG surface, although newly formed crystals only slightly adhered to the CG surface. When OPN-immobilized CG was used, marked adherence and aggregation of seed crystals were observed, in addition to the relatively increased adherence of newly formed crystals. When FN/THP-immobilized CG was used, newly formed crystals only slightly adhered to the CG surface, although the degree of seed crystal adherence and aggregation did not significantly change. Conclusions: These findings suggest that the immobilization of OPN to the CG surface enhances the adherence and aggregation of seed crystals, as well as enhancing the adherence of newly formed crystals, resulting in decreased IA of CG (overall promotion of crystal deposition). Therefore, the results of this study clarified that OPN enhances the formation and aggregation of CaOx crystals in this experimental system.

The low incidence of atherosclerosis and other degenerative disease, including urolithiasis, in the Greenland Eskimo has been attributed to their high consumption of oily fish with its high concentration of eicosapentaenoic acid (EPA). With a westernized diet, the oxygenated products of renal prostaglandin synthesis are metabolites of the n-6 series and these are known to play important roles in several pathophysiological processes involved in calcium stone formation. Buck's group presented a hypothesis that the initiating factor for lithiasis triggers prostaglandin synthesis, and showed that this influenced by EPA treatment.In order to ascertain the effects of EPA on plasma lipids and urinary parameters, we undertook a clinical study whereby a highly purified preparation was administrated (1,800 mg/day) to 88 patients with urinary stones for 3 months (short term) and 18 months (long term).Hyperlipemia improved the affected individuals and urinary calcium was significantly reduced in the hypercalciuric but not in the normocalciuric group.The results suggest that EPA by reducing urinary calcium might favorably affect urine composition in a way that possibly reduces the risk of calcium stone formation.

We recently reported that osteopontin (OPN) and calprotectin (CPT) are present in the matrix of urinary calcium stones, and that OPN mRNA is expressed in the renal distal tubular cells. In the present study, we examined the immunohistochemical distributions of OPN and CPT in urinary stones. The stones used in this study were passed spontaneously from the upper urinary tract. One half of each of the stones was analyzed with an infrared spectrophotometer, and were shown to be comprised of calcium oxalate, calcium phosphate, uric acid and cystine. The other half of each stone was immersed in tetrasodium ethylenediamine-tetraacetate (EDTA) solution. The half-stones were embedded in paraffin and cut into 5-microm sections. The avidin-biotin-peroxidase complex technique was employed. A monoclonal antibody to human milk-derived OPN and a monoclonal antibody to human granulocyte-derived CPT were used as primary antibodies. The immunochemical study using the OPN and CPT antibodies showed positive staining of the matrix of the urinary calcium stones. The stones showed staining in two distinct zones: a core area was stained with randomly aggregated OPN and CPT, and peripheral layers were stained in concentric circles. On the basis of our observations, it is reasonable to presume that OPN and CPT play roles as the matrix in the structure of urinary calcium stones.

Inhibitory effects of female sex hormones on urinary stone formation in rats. Background The effects of female sex hormones on urinary stone formation are not known. This study was conducted to investigate the effects of these hormones on stone formation by using an ethylene glycol (EG) and vitamin D-induced rat urolithiasis model. Methods Adult female Wistar rats were fed the same diet for four weeks and were then divided into four groups ( N = 10 each). One group was administered 0.5 ml of olive oil three times per week for four weeks as a control. The other three groups were administered 0.5 μg of vitamin D 3 and 0.5 ml of 5% EG three times per week for four weeks. The rats in two of these three groups were oophorectomized, and the rats of the remaining group underwent a sham operation on the day before the start of the four-week treatment period. One of the two oophorectomized groups was then administered a supplementation of female sex hormones (0.1 mg of estrogen and 2.5 mg of progesterone 3 times per week for 4 weeks). On the first day of the fifth week of the experimental period, the degree of crystal deposition was determined histologically, and the calcium content in renal tissue was measured. We also investigated the level of osteopontin (OPN) mRNA in renal tissues by Northern blot analysis. OPN is a matrix protein thought to be a promoter of stone formation. Results The urinary oxalate excretion, crystal deposition and calcium content in renal tissue and the expression of OPN-mRNA were greater in the oophorectomized rats compared with the controls, and the same parameters were inhibited by the female sex hormone supplementation. Conclusions These results suggest that female sex hormones can inhibit renal crystal deposition in EG-treated rats by suppressing the urinary oxalate excretion and the expression of OPN.

The canine renal distal tubular cell line Madin-Darby canine kidney (MDCK) forms calcium phosphate microliths during a long-term culture in vitro. We identified osteopontin (OPN) and calprotectin (CPT) from a urinary stone matrix. We recently also detected the expression of OPN and CPT in MDCK cells. The relationship between the mechanism of the stone formation and these stone matrix proteins is not yet known. Here, MDCK cells were cultured and inoculated in the subcutis of nude mice. After 4, 8 and 12 weeks, the inoculated tissues were resected, fixed and immunostained with polyclonal anti-human OPN and polyclonal anti-human CPT antibodies. Some serial specimens were stained with von Kossa's procedure. MDCK cells formed some follicular formations in the subcutis of nude mice at least at 12 weeks after transplantation. At 8 weeks after the inoculation, we detected small calcium phosphate stones with MDCK cells trapped in the follicles. The cells forming the stones also expressed both OPN and CPT. The CPT expression sites coincided with the stone formation sites. We confirmed that MDCK cells inoculated in nude mice had stone-forming potential, and we speculate that OPN and CPT play important roles in stone formation by MDCK cells.

Kampo medicine is a traditional Japanese therapeutic system which originated in China and was used to treat various diseases for hundreds of years. Kampo medicine had been also used for the cure and the prevention of urinary calculi for many years, but the effect and the mechanism of this use of kampo medicine are unclear. We examined the inhibitory effect of the kampo medicine takusha on the formation of calcium oxalate renal stones induced by ethylene glycol (EG) and vitamin D3 in rats. We also investigated the effect of takusha on osteopontin (OPN) expression, which we previously identified as an important stone matrix protein. The control group rats were non-treated; the stone group rats were administered EG and vitamin D3, and the takusha group was administered takusha in addition to EG and vitamin D3. The rate of renal stone formation was lower in the takusha group than in the stone group; thus, the OPN expression in the takusha group was smaller than in the stone group. Takusha was effective in preventing oxalate calculi formation and OPN expression in rats. These findings suggest that takusha prevents stone formation including not only calcium oxalate aggregation but also proliferation.

We recently reported that the addition of the protein osteopontin (OPN) resulted in an increase in the deposition of calcium oxalate (CaOx) crystals on the surface of Madin Darby canine kidney (MDCK) cells. To determine the degree to which this increased deposition is caused by OPN, we investigated the extent to which the CaOx crystal deposition produced by the expression of OPN at the cell surface was suppressed by 4 different methods prior to the determination of the level of CaOx crystal binding. MDCK cells (2 × 106 cells/well) were cultured to a confluent state, and the binding of OPN to the cellular surface was then inhibited by adding one of the following 4 substances: human OPN polyclonal antibody, thrombin, cyclic Arg-Gly-Asp (RGD) peptides and tunicamycin. The cells were cultured for 24 h. We then used a fluorescent antibody technique with an OPN polyclonal antibody to determined whether the expression of OPN at the cell surface was inhibited, and we measured the degree of CaOx crystal deposition using the isotope 45Ca. The degree of CaOx crystal deposition was inhibited by 80% or more in the antibody-treated group, by 50–80% in the thrombin-treated group, by 60–80% in the cyclic RGD-treated group, and by 50–60% in the tunicamycin-treated group. These results suggest that OPN in the extracellular matrix is the main cause of CaOx crystal deposition on the surface of MDCK cells.

PURPOSE: The aim of the present study was to compare sialic acid concentrations of serum and urine specimens in both calcium (Ca)-containing urinary stone formers and non-stone formers. Moreover, we studied inhibitory activity of sialic acid upon the calcium oxalate (CaOx) crystal aggregation and growth. MATERIALS AND METHODS: Sialic acid determinations were done on fresh serum and urine samples of 35 Ca-containing urinary stone formers (stone formers group) and 20 non-stone formers (patient controls group). Inhibitory activity of sialic acid upon the CaOx crystal aggregation and growth was studied by using in vitro assay method of seed crystal system. RESULTS: Serum sialic acid concentrations were found to be similar in the two groups. Urinary sialic acid concentrations were significantly lower in the urine specimens of stone formers than in their patient controls. Sialic acid showed a dose dependent inhibitory activity upon the CaOx crystal aggregation and growth into seed crystal method. CONCLUSION: It is suggested that urinary sialic acid may play some role during the phase of stone formation from the results of the present study, because sialic acid shows marked inhibitory activity upon the CaOx crystal aggregation and growth at concentrations higher than 100 mg/dl.

The calciuric response and the changes of plasma glucose and insulin produced by a 75-gram oral glucose tolerance test were determined in 27 male patients with idiopathic calcium renal stones (6 with dietary hypercalciuria, 5 with nondietary hypercalciuria and 16 with normocalciuria) and 22 healthy male subjects. The subjects were classified as obese (or = 120% ideal weight) and nonobese. The incidence of an abnormal response to glucose loading was similar in the stone patients and the healthy subjects. In addition, the plasma glucose and insulin levels after oral glucose load did not differ between the stone patients and control subjects and were affected by the individual degree of obesity. Urinary calcium excretion increased significantly after glucose ingestion in both the stone patients and the control subjects. Urinary calcium excretion was greater in the stone patients than in the control subjects due to the presence of patients with nondietary hypercalciuria, and the increment in urinary calcium excretion in the dietary hypercalciuric and normocalciuric stone patients was indistinguishable from that in the control subjects. The degree of obesity did not affect the increment in urinary calcium excretion. These results suggest that overconsumption of refined carbohydrates such as sugar-sweetened soft drinks, soda and cakes may be a risk factor for stone formation, especially in the patients with nondietary hypercalciuria.

Pathogenesis of urolithiasis cannot be explained only by metabolic disorder. In the present study, morphologic differences of the renal pelvic-caliceal system (PCS) were examined on both the stone and normal sides in calcium-containing stone formers. The results indicated that as compared to the normal side, the urine flow in the PCS was stagnant or not straight on the stone side even in the same individual, showing unfavorable conditions for stone formation. It is therefore considered that morphologic disorders of the urinary tract may be one of the causes for stone formation.

The relationship between the degree of metabolic acidosis and calcium phosphate stone formation was studied. Furthermore, the reasons why renal tubular acidosis (RTA) and primary hyperparathyroidism (PHPT) dominantly occur in women, and female stone formers more often produce calcium phosphate stone are discussed. Blood was slightly more acidotic in women than in men in both the urolithiasis and the control groups. Likewise, blood was significantly more acidotic and urinary pH significantly higher in patients with PHPT. Patients with RTA had severe metabolic acidosis, and urinary pH was highest among all groups. Calcium phosphate concentration was significantly higher in women than in men, and was also higher in patients with PHPT than in those with urolithiasis. All patients with RTA had pure calcium phosphate stones. The reasons why females are more acidotic and have more calcium phosphate in stones are suspected to be related to progesterone and urinary tract infection.

Because human urine contains various substances which can affect each other, it is quite difficult to clarify the mechanism of formation of calcium oxalate (CaOx) crystal in urine. The authors recently determined CaOx crystalline content and the concentrations of other substances in urine specimens from patients with urolithiasis and healthy volunteers, and subjected the data to multi-regressive analysis for the purpose of assessing the effect of these urinary substances on CaOx crystal formation. 1. In analysis of urine from patients with urolithiasis, the partial correlation coefficients of CaOx crystal formation with oxalic acid, sodium, calcium, uric acid magnesium were 0.67, 0.28, 0.18, and -0.10, respectively. The formula of regression was as follows: Amount of CaOx crystal (X 10(6) microns3/ml) = 3.59 X 10(-2) Ox (mM/L) + 4.72 X 10(-3) Ca (mM/L) + 4.52 X 10(-3) Na (mM/L) + 2.51 X 10(-4) UA (mM/L) -2.39 X 10(-2) Mg (mM/L) -1.65. The multiple correlation coefficient was 0.759. Thus, in patients with urolithiasis, urinary crystal formation was most dependent on the oxalic acid level, sodium, calcium, and uric acid were found to promote crystal formation, while magnesium to suppress it. 2. In analysis of urine from healthy volunteers, the partial correlation coefficients of CaOx crystal formation with oxalic acid and inorganic phosphorus were 0.51 and -0.24, respectively. The formula of regression was as follows: Amount of CaOx crystal (X 10(6) microns3/ml) = 1.91 X 10(-2) Ox (mM/L) -3.43 X 10(-4) P (mM/L) +0.29 The multiple correlation coefficient was 0.525.(ABSTRACT TRUNCATED AT 250 WORDS)

With the development of extracorporeal shock wave lithotripsy treatment, the duration of hospitalization for stone patients fortunately has become shorter. However, a detailed analysis of lithogenesis is not possible during such patients' short hospital stays. We prepared a standard diet to be eaten at home for investigation of lithogenesis at the out-patient clinic. This diet was nutritionally well-balanced and contained the following: energy: 2000 Kcal, total protein: 70-75 g, animal protein: 30-35 g, carbohydrate: 510 g, fat and oil: 50-60 g, calcium: 600-630 mg and magnesium: 320 mg. The urine of 24 male patients with stones on a free diet and the same patients after 3 days on the standard diet was analyzed for urea-nitrogen, uric acid, sodium, calcium, phosphorus, magnesium, citric acid and oxalic acid. The results were compared with those in 17 healthy male subjects who were eating the standard diet (controls). It was found that 66% of hypercalciuria (greater than = 300 mg/day) on a free diet became normocalciuria on the standard diet. The hypercalciuria was therefore thought to be of dietary origin. Moreover, urinary excretion of urea nitrogen, uric acid, sodium and phosphorus by patients remarkably decreased after 3 days on the standard diet, which was not different from that of controls. These results suggest that the standard diet at home is useful in the screening of hypercalciuria and also quite adequate for patients with stones.

Objectives To analyze the changes in the annual incidence and epidemiologic details of lower urinary tract stones in Japan, a nationwide survey of urolithiasis was performed. Methods Data were obtained from all patients who had been diagnosed by urologists in 2005 as having lower urinary tract stones, including both first and recurrent stones. The data were separately enumerated according to hospital size, irrespective of admission and treatment. The study included all hospitals approved by the Japanese Board of Urology and thus covered nearly all urologists practicing in Japan. The estimated annual incidence according to sex, age, and stone composition was compared with other nationwide surveys taken from 1965 to 1995. Results The incidence of lower urinary tract stones in Japan has steadily increased from 4.7/100 000 in 1965 to 9.1/100 000 in 2005. However, the age-standardized annual incidence of lower urinary tract stones in Japan decreased slightly from 5.5/100 000 in 1965 to 5.4/100 000 in 2005. The incidence of stones containing calcium has significantly increased from 50.7% to 72.0% among men and the incidence of infection-related stones has decreased significantly from 26.2% to 10.1%. The ratios of uric acid calculi in men and of infection-related stones in women increased with age. Conclusions The increased incidence of lower urinary tract stones is in slight contrast to the sudden increase in the incidence of upper urinary tract stones, which might be associated with the aging of the Japanese population.

High-performance liquid chromatography (HPLC) monitoring with an ultraviolet detector was carried out to measure urinary oxalate levels in urolithiasis. Interfering substances in urine were removed by anion exchange prior to chromatography. This procedure was found excellent with respect to sensitivity, reproducibility, and analytical recovery. The findings were in agreement with colorimetric date. The mean oxalate level in 24-hour urine was 30.5 +/- 15.1 mg in patients with a single episode and 36.3 +/- 9.8 mg in recurrent stone formers. The latter values was significantly higher than the normal control level (27.4 +/- 3.8 mg).

Factors relating alterations in plasma and urine composition to recurrence of urinary stones during drug therapy were investigated by using a multiple regression analysis technique. These factors were influenced not only by the efficacy of the drugs but also by other factors (plasma or urinary constituents and overall health of the patients, etc.). In order to study the effect of drug therapy or other treatment on the alteration of plasma and urine constituents, multiple regression analysis is more appropriate than Student's paired t-test which has been used by some workers. These two analytical methods yield different results even if used on the same data.

The effects of Glu and Asp on calcium stone formation was evaluated in three experiments. Studies using mixed suspension, mixed product removal crystallization and scanning electron microscopy showed that Glu and Asp inhibited the nucleation rate, growth rate and suspension density (crystal mass produced) in proportion to the concentration. The main amino acids in calcium oxalate stones and calcium phosphate stones were Glu and Asp. However, the main amino acids in uric acid stones were glycine and urea, and there were no specific amino acids in struvite stones. The activity of urinary GOT and GPT, which convert Asp and alanine, respectively, to Glu in normal subjects was significantly greater than in calcium stone formation.

Using seed crystal method, whole-urine method, and scanning electron microscopy, the inhibitory effects of sialic acid and osteopontin (OPN) on aggregation/growth of CaOx crystals were investigated. Using the seed crystal method, sialic acid showed an inhibitory effect on CaOx crystal aggregation/growth in a concentration-dependent manner, but almost no effect was observed using the whole-urine method. OPN showed an inhibitory effect on aggregation/growth in both experimental systems. The inhibitory effect of asialo-OPN on aggregation/growth was approximately 20% lower than that of OPN in the experiment using the seed crystal method and approximately 15% lower in the experiment using the whole-urine method. Scanning electron microscopy showed that OPN and sialic acid inhibit the aggregation of CaOx crystals. The above findings show that sialic acid accounts for about 15–20% of the involvement of OPN in CaOx crystallization.

Osteopontin (OPN) is a urinary protein which inhibits calcium oxalate (CaOx) crystal growth in the seed crystal system. The aim of this study was to evaluate the effects of OPN immobilized on collagen granules (CG) for CaOx crystal growth and aggregation in this system. OPN-immobilized CG showed a 30% decrease in inhibitory activity compared with non-OPN-immobilized CG. Scanning electron microscopy revealed that 1) OPN-immobilized CG showed more marked aggregation and adhesion of seed crystals (smaller than 0.5 microm in diameter) than non-OPN-immobilized CG, 2) the amount of adherent large type crystals (2-3 microm in diameter) did not differ between OPN immobilized and non-OPN-immobilized CG. In conclusion, immobilized OPN promotes aggregation and adhesion of CaOx crystals smaller than 0.5 microm on CG. These observations suggest that crystal adhesion to immobilized OPN plays a role in the retention of crystals in the kidney.

Background: The effect of ethyl icosapentate (EPA-E) on urinary calcium and oxalic acid excretion was examined to evaluate whether EPA-E is useful in the prevention of calcium-containing urinary stones. Methods: For 6 months, urine was measured daily from 40 calcium-containing urinary stone producers at an outpatient clinic, before and after the administration of 1800 mg/day EPA-E. The urine was measured for volume, urea nitrogen, creatinine, calcium, magnesium, phosphorus, uric acid, oxalic acid and citric acid. Serum total cholesterol and triglyceride were also measured. Results: Urinary calcium excretion was not reduced in any of the patients or particular hypercalciuric groups, nor did the level of calcium change. However, nine of the 25 hypercalciuric patients experienced a significant urinary calcium reduction to the normal calciuric level (a reduction of approximately 44%). It is not known why these particular patients experienced a reduction. Urinary oxalic acid did not change, whether hypercalciuria was present or not. Conclusions: These findings suggest that EPA-E is not particularly effective in reducing urinary calcium excretion in the hypercalciuric patients, but it needs future investigation because some patients experienced significant urinary calcium reduction.

alpha(2)HS-Glycoprotein (HS), a crystal surface binding substance extracted from human urine, is considered to be one of the urinary macromolecular inhibitors in urolithiasis. In the present study, reverse transcription-polymerase chain reaction was used to examine HS mRNA expression, and immunohistochemical staining was used to reveal its localization in the human kidney. The inhibitory effects of recombinant human HS and native human HS on calcium oxalate crystal growth were examined in a seed crystal system. HS mRNA was found to be expressed in the human kidney, and it was located in the epithelial cells of distal and proximal renal tubular cells. However, neither recombinant HS nor native HS had an inhibitory effect on crystals in the protein concentration of urine of healthy humans. HS in the urine, therefore, does not seem to be a potent inhibitor in stone formation.

Proteins were extracted from uric acid stones with 6M guanidine chloride (pH 8.5), which were successively developed by 12% polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE). Amino acid sequence analysis of each band on SDS-PAGE revealed that major components in uric acid stones were immunoglobulin alpha heavy and kappa light chains. Although immunoglobulin heavy chain (gamma and mu, as well as alpha) and a kappa light chain were clearly detected in uric acid stones by Western blotting using their specific antibodies, no lambda chains whatsoever could be detected. The results suggest that immunoglobulins selectively containing kappa light chain might have specific functions in uric acid stone formation as stone matrices.

All urinary stones contain an organic matrix which comprises approximately 2 to 5 per cent of the total stone weight. The matrix may be involved in the pathogenesis of urinary stone formation. Despite intensive investigation the role of this material in lithogenesis remains to be understood.

In patients with cystinuria, recurrence of calculi is prevented by increasing the urine volume, alkalinizing the urine and administering a- mercapto-propionylglycine (MPG)1. Long-term high-dose administration of MPG has been known to cause side effects such as hepatopathy, dermatopathy and nephropathy. On the other hand, captopril, an angiotensin-converting enzyme inhibitor (ACE inhibitor) used as a hypertensive drug, exhibits sulfhydryl-binding (SH-binding) in the same way as MPG, and produces a disulfate compound by reacting with cystine. Solubility of this disulfate is about 4 times as high as that of MPG2. In this study, ACE inhibitor was administered to patients with cystinuria and its efficacy evaluated.

In a previous study we showed that the magnesium-calcium ratio of tap water is negatively correlated with the incidence of calcium-containing urinary stones. In this study we examined the relationship between the incidence of struvite stones, water hardness and the regional geological features on the basis of our previous study and an epidemiological study of urolithiasis performed in Japan. The magnesium-calcium ratio of tap water was found to correlate positively with the incidence of struvite stones. The tap water magnesium-calcium ratio was high in regions of basalt and sedimentary rock and was low in granite and limestone areas. The incidence of struvite stones in the regions of basalt and sedimentary rock was higher than that in the granite and limestone areas. Thus, this study suggested that the incidence of struvite stones is related to the magnesium-calcium ratio of tap water and to the regional geology, as is the case for calcium-containing stones.

Preoperative localization of parathyroid tumors by computed tomography (CT), thallium-201/technetium-99m pertechnetate subtraction scintigraphy (Tl-201/Tc-99m), ultrasonography (US), and magnetic resonance imaging (MRI) was compared in patients with hyperparathyroidism (HPT) to examine the characteristics of each method. A total of 87 patients with HPT were divided into two groups according to the time when they were examined. Patients in group I were examined before MRI had been introduced in our hospital, and a 2.5-MHz transducer probe was used for US. Those in group II were examined by MRI and US using a 7.5-MHz transducer probe. Group I included 45 patients (36 with primary hyperparathyroidism [PHPT] and 9 with secondary hyperparathyroidism [SHPT]), and group II included 42 patients (15 with PHPT and 27 with SHPT). In both PHPT and SHPT and SHPT of group I and PHPT of group II, there was no significant difference in detection rates between all diagnostic methods. In patients with SHPT in group II, the detection rate was significantly higher for CT than for Tl-201/Tc-99m and MRI (both p less than 0.01), and for US than for Tl-201/Tc-99m (p less than 0.01). In both groups I and II, the detection rate of each study method was significantly higher in patients with PHPT than in those with SHPT (all p less than 0.01). Compared with group I, the rate was significantly improved in group II, in both types of patients. Regarding the location of the parathyroid tumor, the detection rate of CT was significantly higher for upper parathyroid glands than for lower glands, whereas that of US and Tl-201/Tc-99m was significantly higher for lower glands. The detection rate sharply increased when the tumor weight reached 250 mg (CT, US) or 1,000 mg (Tl-201/Tc-99m, MRI).

We have developed a new assay technique using high-performance liquid chromatography. The assay was performed at a flow rate of 0.7 ml/min, a temperature of 60 degrees C and an ultraviolet absorption of 214 nm. Comparison of the results of the new assay with the results obtained for identical samples using the conventional fluorometric method demonstrated a very high correlation coefficient of 0.931.

The in vivo anticancer effects of high energy shock waves (HESW), on bladder cancer induced by N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN), were studied in the rat using the Siemens lithotriptor (Lithostar). There was no significant difference in the anticancer effects in delaying tumor growth, measured as the whole bladder weight including the weight of the cancer, between the groups with and without exposure to HESW. However, light microscopic examination revealed extensive submucosal bleeding and exfoliation of mucosa, and electron microscopic examination revealed degeneration of pleomorphic microvilli, swelling of mitochondria, and destruction of mitochondrial cristae in the cancer cells in bladders exposed to HESW. Flow cytometric determination of DNA content in the cancer cells exposed to HESW indicated a selective diminution of cells in the G2 and M phases and an increase of cells in the G0 and G1 phases of the cell cycle. While the mechanism of HESW-induced anticancer effect could not be determined on the basis of this study, these changes in the morphology and the cell cycle of cancer cells induced by HESW exposure suggest some kind of biological effects following exposure to HESW. It is expected that HESW be an effective method for the treatment of human cancer in combination with chemotherapy and radiation.

We developed 2 simple and rapid tests for measurement of constituent concentrations and the stone-forming tendency of urine in the outpatient clinic. The concentrations of urinary constituents of calcium, magnesium, phosphorus, uric acid and oxalic acid were measured using 2 types of simple colorimetric tests (vial and quantitative filter types). The intensity of the color developing after a given interval was compared with a color standard of 4 levels. The results obtained using the colorimetric test were slightly lower in value than but significantly correlated with those obtained with standard measurements. The second test measured the crystal-forming ability of urine. A 10 ml. urine sample was pipetted into 4 vials that each contained different concentrations of oxalic acid and calcium. After a given interval the turbidity in each vial was compared with a control (0 mg. oxalic acid and calcium). If turbidity occurred in urine with low concentrations of oxalic acid and calcium the sample had a large tendency for crystals to form.

The interaction of calcium oxalate crystals and renal tubular cells was studied. Rat renal collecting tubular cells were cultured and immunologically stained with anti-type-IV collagen antiserum (type-IV collagen exists in renal tubular basement membrane). When renal tubular cells and calcium oxalate crystals were mixed, clumps were formed. These clumps were examined by immunological staining with anti-type-IV collagen antiserum. In another series of experiments, calcium-containing crystals were found to be adsorbed onto mucous threads and cast-like materials, although no such adsorption was observed on squamous cells. These absorbed materials interacted with anti-type-IV collagen antiserum. These results suggest that collagen in the renal tubular basement membrane may act as matrix in urinary stone formation.

To estimate the epidemiology of upper urinary stones in the elderly, a total of 1,957 patients (1,349 men and 608 women) with urolithiasis were studied. The ratio of men to women was approximately 3∶1 in middle-aged (between 30 and 59 years), 1∶1 in young (29 or younger) and 1∶1 in old patients (60 or older). Compared with the age distribution of the entire Japanese population, the incidence of urinary stones was very low in both male and female children, twice as high in middle-aged men, slightly higher in middle-aged women, and equal or slightly lower in the male and female elderly. Stones of calcium oxalate and uric acid occurred more frequently and those of calcium phosphate and struvite less frequently in men than in women. This tendency was especially obvious in the middle-aged. In the old generation, calcium oxalate stones occurred almost equally in men and women. Results of urinary stone analysis were similar among men of the three generations, although the incidence of uric acid stones increased with patient age. In women, however, the incidence of calcium oxalate was higher in the young and old generations, while that of calcium phosphate was higher in the middle-aged.

The daily consumption of various nutrients as well as the daily habits of 241 male stone patients were investigated. Hypercalciuric (300mg. or more per day) calcium stone patients ingested much more total protein, fats, oils and calcium than normocalciuric calcium stone patients, and uric acid stone patients ingested much more total and animal protein, and carbohydrates than calcium stone patients. However, the amount of ingested calcium by the patients (470mg.) was similar to that of age-matched healthy male subjects (476mg.) and did not reach the level of the daily nutritive requirements (600mg.). The patients ingested large amounts of nutrients, especially animal protein, during the evening meal. From these results it was believed that synthetic dietary management, including not only ingesting various amounts of nutrients but also changing dietary habits, is necessary for the prophylaxis of renal stones.

Bone mineral contents of calcium urolithiasis patients (105 males and 52 females) were measured by the microdensitometry (MD) method, and the patients were divided into the MD normal group and the MD abnormal group. The patients were also divided into the group (21 males and 3 females) treated with thiazides for 1 year or more and the nontreated group to examine various factors in blood and urine. [Nontreated group] The rate of MD abnormality was higher in younger males. The rate tended to increase with age in females. Alkaline phosphatase values were significantly higher in MD abnormal group males than in MD normal group males. Urinary calcium excretion and PTH values were significantly higher in MD abnormal group females than in MD normal group females. Comparison of hypercalciuria and normocalciuria revealed no significant difference between the MD normal rate and the MD abnormal rate. Comparison of single of stone formers and recurrent stone formers also revealed no significant difference between the MD normal rate and the MD abnormal rate. [Treated group] PTH and alkaline phosphatase values were significantly higher in the treated group than in the nontreated group. Alkaline phosphatase values were significantly higher in the MD abnormal group. From the viewpoint of stone recurrence prevention, the monitoring of bones where the majority of calcium in the body is present is considered important besides behavior of calcium in blood and urine.

The crystallization of calcium oxalate in the urine of patients with hyperparathyroidism and hyperthyroidism was studied using a mixed suspension mixed product removal (MSMPR) system. In addition, calcium metabolism in hyperthyroidism and its relationship to urolithiasis was investigated. The urines from all the three groups (normal subjects, hyperparathyroid and hyperthyroid patients) showed reduced nucleation rates and increased growth rates in comparison with the control synthetic urine. The nucleation rate was not significantly different between the three human urine groups, while the growth rate was significantly higher in the hyperparathyroid group compared to the normal and hyperthyroid groups. Crystal volume (suspension density) in the hyperparathyroid group was approximately twice that in the other two groups. Serum and ionized calcium levels in hyperparathyroid patients were higher than in normal subjects, while hyperthyroid patients had levels only slightly higher than those in normal subjects. The hyperparathyroid and hyperthyroid groups differed significantly from the normal group in urinary calcium excretion. These two groups also showed significantly higher levels of serum alkaline phosphatase and urinary hydroxyproline than did the normal group. Although hyperthyroid patients have a calcium metabolism similar to hyperparathyroid patients, the incidence of urolithiasis is no different between hyperthyroid and normal subjects. The results of both crystallization and calcium metabolism in hyperparathyroid patients were not significantly different between those with and without urolithiasis. The result of crystallization was also not significantly different between hyperparathyroid patients with and without hypercalciuria. This study suggests that hypercalciuria alone does not produce urinary stones and that urine from hyperparathyroid patients may contain promotors of calcium oxalate crystallization and calcium stone formation.

Serum osteocalcin, also called bone gla protein, is one of sensitive and specific markers for metabolic bone diseases. Current evidence suggests that the protein may be involved in the regulation of calcium homeostasis in bone. We measured serum osteocalsin levels by radioimmunoassay in 100 patients with urolothiasis, especially in calcium containing stone formers and evaluated the influence of bone metabolism on the formation of calcium-containing stones. Although serum osteocalcin levels in most patients were normal, those of two male and four female patients were high. We considered that they were patients with renal hypercalciuria and secondary hyperparathyroidism and in them the formation of calcium containing stones were influenced by disorder of bone metabolism. In addition, we suggest that serum osteocalcin levels may be available index for the effect of treatment in stone formers with renal hypercalciuria and bone disease.

We examined the relationship among magnesium and calcium content in tap water, the geological features and urinary stone incidence in Japan. The magnesium-to-calcium ratio in tap water correlated negatively with the incidence of urolithiasis. There was no correlation between calcium and magnesium concentration in tap water and urinary stone incidence. Geological features in Japan were classified into 5 groups. The magnesium-to-calcium ratio in the basalt areas was higher than in the other areas, while ratio in the granite areas was low. In the sedimentary rock areas calcium and magnesium concentrations were high; the magnesium-to-calcium ratio in these areas was between those of the basalt and granite areas. The limestone areas had a much higher calcium concentration. The incidence of urinary stones in the sedimentary rock and basalt areas was lower than that of the granite areas, while that in the limestone areas was the highest. Thus, the incidence of urinary stone is related to the magnesium-to-calcium ratio in tap water and the geological area.

Serum-ionized calcium (Ca++) was measured in 65 patients with idiopathic calcium urolithiasis. The patients were then divided into hypercalciuric and normocalciuric groups based on the mean + SD of the control group, with greater than 180 mg/24 h in males and greater than 176 mg/24 h in females defined as hypercalciuria. The results showed a decrease in the tubular reabsorption of calcium in the hypercalciuric group, but not in the normocalciuric group. The hypercalciuric group was then further divided into group I with increased filtered load and group II with with normal filtered load. It was suggested that the group I hypercalciurics had absorptive hypercalciuria and group II renal hypercalciuria.

The relationship between the interval from dinner until retiring and the concentration of various substances secreted into the urine during sleep was studied in 69 healthy men who had eaten the same meal. The specific gravity and the concentrations of creatinine, uric acid and magnesium in the morning spot urine were highest in subjects who had retired within 2 hours after dinner. The concentrations of calcium and oxalate in the morning spot urine were highest in those who had retired between 2 and 4 hours. The specific gravity and urinary concentrations of creatinine, uric acid and oxalate were markedly higher in those with the interval less than 4 hours than in those 4 hours or longer. The concentrations of calcium, magnesium and citrate were not significantly different between the two groups. From these results, we recommend that the interval from dinner until retiring be prolonged and fluid be drunk before going to bed to decrease the concentration of lithogenic substances during sleep.

Only glutamic acid (Glu) and aspartic acid (Asp) are acidic amino acids and are negatively charged in ordinary human urine (pH 5.5–6.5). These amino acids and oxalate have a carboxyl group and are suspected to act competitively with each other in Ca stone formation. These factors were considered in the present study which was designed to evaluate the effect of Glu and Asp on Ca stone formation.