Publications by authors named "Kazuhiro Niimi"

Objectives: To experimentally evaluate the clinical application of N-methyl-4-isoleucine cyclosporin, a novel selective inhibitor of cyclophilin D activation.

Methods: In vitro, cultured renal tubular cells were exposed to calcium oxalate monohydrate crystals and treated with N-methyl-4-isoleucine cyclosporin. The mitochondrial membrane was stained with tetramethylrhodamine ethyl ester perchlorate and observed.

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Purpose: We developed an in vitro system composed of renal tubular cells, adipocytes and macrophages to simulate metabolic syndrome conditions. We investigated the molecular communication mechanism of these cells and their involvement in kidney stone formation.

Materials And Methods: Mouse renal tubular cells (M-1) were cocultured with adipocytes (3T3-L1) and/or macrophages (RAW264.

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We established an experimental co-culture system for renal tubular cells and adipocytes to investigate kidney stone formation mechanisms under metabolic syndrome (MetS) conditions and examined the interaction between these cells morphologically and genetically. M-1s and 3T3-L1s were cultured individually (control, CON), with 24-h culture media from each cell type added to the other cell type (replacement, RP) in 2-layer co-culture dishes for 24 h (transwell, TW). M-1s were then exposed to calcium oxalate monohydrate (COM) crystals, and attached (14)C-labeled COM crystals were quantified.

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To evaluate the efficacy of company-initiated training of urologists on shock wave lithotripsy (SWL) treatment results, we retrospectively assessed 602 patients who underwent SWL in Nagoya City University Hospital between January 2004 and June 2011 using Lithotripter S (Dornier MedTech, Japan). Training-provided by a training specialist of the company in June 2010-focused on the targeting of renal and proximal ureter stones with a combination of radiography and ultrasonography (US). The stretcher wedges were positioned in the semi-prone position or the semi-supine position for middle and distal ureter stones, respectively.

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Renal tubular cell injury induced by oxalate plays an important role in kidney stone formation. Water containing oxygen nano-bubbles (nanometer-sized bubbles generated from oxygen micro-bubbles; ONB) has anti-inflammatory effects. Therefore, we investigated the inhibitory effects of ONB water on kidney stone formation in ethylene glycol (EG)-treated rats.

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The aims of the present study were to elucidate a possible mechanism of kidney crystal formation by using a metabolic syndrome (MetS) mouse model and to assess the effectiveness of adiponectin treatment for the prevention of kidney crystals. Further, we performed genome-wide expression analyses for investigating novel genetic environmental changes. Wild-type (+/+) mice showed no kidney crystal formation, whereas ob/ob mice showed crystal depositions in their renal tubules.

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Urinary stones consist of two phases-an inorganic (mineral) phase and an organic (matrix) phase. Studies on the organic components of kidney stones have been undertaken later than those on the inorganic components. After osteopontin was identified as one of the matrix components, the biomolecular mechanism of urinary stone formation became clearer.

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Renal tubular cell injury induced by oxidative stress via mitochondrial collapse is thought to be the initial process of renal calcium crystallization. Mitochondrial collapse is generally caused by mitochondrial permeability transition pore (mPTP) opening, which can be blocked by cyclosporine A (CsA). Definitive evidence for the involvement of mPTP opening in the initial process of renal calcium crystallization, however, is lacking.

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In 2002, speedy elimination of ureterolithiasis in the lower part of ureter was first reported with the alpha 1 blocker. Thereafter, there are a lot of reports including meta-analysis about tamsulosin. In 2011 EAU Guidelines on Urolithiasis, it is the most important to establish effective MET (medical expulsive therapy) to facilitate spontaneous stone passage.

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Osteoporosis is characterized by a reduction in bone mineral density (BMD) . Reduced BMD has been reported in urolithiasis patients with hypercalciuria, as well as in those with normocalciuria. Bisphosphonates potently inhibit bone resorption and are used in the management of osteoporosis.

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We studied the effects of cholesterol load on urinary stone in rats receiving a standard diet or a high fat diet. Sixty male rats were randomized to two groups and were fed either a standard diet (SD group) or a high fat diet (HFD group) for 8 weeks. Then the two groups were further divided into four groups.

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Osteopontin (OPN) has been described to play a nonredundant role in the formation of renal crystals. This biological activity of OPN may be attributed to its characteristic structure, which includes 2 calcium binding sites, Arg-Gly-Asp (RGD) sequences. To test this hypothesis, we evaluated wild-type mice (WT group), OPN-knockout mice (KO group), and two types of transgenic mice : (1) one type carrying a transgene in which the sequences coding for the 2 calcium-binding sites of the OPN were deleted (CaX group) and (2) the other type carrying a transgene in which the sequence that codes for the RGD sequence of the OPN was modified to one that codes for Arg-Gly-Glu (RGE ; RGE group).

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Mice have a strong ability to eliminate renal calcium oxalate crystals, and our previous examination indicated a susceptibility in which monocyte-macrophage interaction could participate in the phenomenon. To clarify the macrophage-related factors playing roles in the prevention of crystal formation in mouse kidneys, morphologic and expression studies based on microarray pathway analysis were performed. Eight-week-old male C57BL/6N mice were administered 80 mg/kg of glyoxylate by daily intraabdominal injection for 15 days, and the kidneys were extracted every 3 days for DNA microarray analysis.

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Renal stone formation and renal failure among Chinese infants administered melamine-containing formula were increasingly reported in 2008. We investigated the mechanism by which melamine and cyanuric acid induce renal stone formation and renal failure. Ten-week-old rats were administered either melamine [2.

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We describe a case of embryonal rhabdomyosarcoma of the prostate in a 20-year-old man with a history of acute lymphatic leukemia at 6 years of age. He presented with gross hematuria and high fever. The level of prostate-specific antigen (PSA) was 27.

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Papillary renal cell carcinomas (RCC) are the second most frequently identified pathological subtypes of RCC. Occasionally, papillary RCC demonstrate pathological characteristics of renal oncocytomas (RO), benign renal tumors. We report the case of an 81-year-old woman with an oncocytic papillary RCC, which was difficult to differentiate from a hybrid of RO and papillary RCC, who underwent left radical nephrectomy.

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