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Monohydrate Crystals (monohydrate + crystal)
Kinds of Monohydrate Crystals Selected AbstractsPhase transition of L -Ser monohydrate crystal studied by 13C solid-state NMR,MAGNETIC RESONANCE IN CHEMISTRY, Issue 3 2006Tsunenori Kameda Abstract We used gravimetric analysis (GA) and 13C solid-state nuclear magnetic resonance (NMR) to study solid-phase transition from the transparent single crystal of L -serine (L -Ser) monohydrate to a turbid powder. We found that L -Ser monohydrate loses water molecules and transforms into an anhydrate, thus experimentally demonstrating Frey's assumption (Acta Cryst., B29, 876, 1973). Application of a handmade cross-polarization (CP) NMR probe with a saddle-type coil to the oriented crystal of the L -Ser monohydrate revealed the dehydration mechanism. Furthermore, the chemical shift tensor components of the carboxyl carbon in L -Ser monohydrate were determined. The difference in the tensor component of ,22 between the monohydrate and anhydrate forms was more than 7 ppm, probably owing to differences in the hydrogen-bonding structure of each form. Copyright © 2006 John Wiley & Sons, Ltd. [source] Resident macrophages initiating and driving inflammation in a monosodium urate monohydrate crystal,induced murine peritoneal model of acute goutARTHRITIS & RHEUMATISM, Issue 1 2009William John Martin Objective To determine whether infiltrating monocytes, neutrophils, or resident macrophages contribute to the early inflammatory response to monosodium urate monohydrate (MSU) crystals in vivo. Methods MSU crystal,induced inflammation was monitored using a peritoneal model of acute gout. The production of proinflammatory cytokines (interleukin-1, [IL-1,], tumor necrosis factor , [TNF,], IL-6) by resident macrophages, infiltrating monocytes, and neutrophils during the onset of gout was determined by flow cytometry. Infiltrating and resident peritoneal cells were cultured with MSU crystals ex vivo, and proinflammatory cytokine production was determined by multiplex cytokine array. Activated macrophages on the visceral epithelial lining of the peritoneum were identified by immunofluorescence histochemistry. The inflammatory immune response to MSU crystals was then compared with the inflammatory response in mice depleted of resident macrophages by pretreatment with clodronate liposomes. Results The production of cytokines in vivo preceded the influx of Gr-1intermediate7/4+ monocytes. Monocytes and neutrophils recruited during the inflammatory phase of the response to MSU crystals failed to produce proinflammatory cytokines either in vivo, or ex vivo following restimulation with MSU crystals. Stimulation of the naive peritoneal resident cell population with MSU crystals ex vivo resulted in positive staining of resident macrophages for the proinflammatory cytokines IL-1,, TNF,, and IL-6. Depletion of the resident macrophage population resulted in a significant decrease in both MSU crystal,induced neutrophil infiltration and proinflammatory cytokine production in vivo despite the presence of infiltrating monocytes. Conclusion These data indicate that resident macrophages, rather than infiltrating monocytes or neutrophils, are important for initiating and driving the early proinflammatory phase of acute gout. [source] Monosodium urate monohydrate crystal,induced inflammation in vivo: Quantitative histomorphometric analysis of cellular eventsARTHRITIS & RHEUMATISM, Issue 6 2002C. Schiltz Objective To quantify the inflammatory cell response in rat air pouch pseudosynovial membrane during monosodium urate monohydrate (MSU) crystal,induced inflammation. Methods In the rat air-pouch model, we used a computer-assisted histomorphometric method to quantify cell distributions, based on cell linear densities, in histologic sections of membranes from pouches injected with MSU or saline. The volume, white blood cell (WBC) count, and histamine content of the pouch exudates were determined at several time points. Results Injection of 10 mg of MSU crystals into the pouch produced an acute exudate. After peaking at 24 hours, the exudate volume and WBC count decreased spontaneously over the next 3 days, simulating the self-limited course of acute gout. Membrane thickness followed a parallel course. Membrane polymorphonuclear cell (PMN) linear densities were closely correlated with exudate WBC counts, suggesting PMN recruitment from the subintimal synovial membrane. Both monocyte/macrophage and mast cell linear densities increased in the subintimal layer 2 hours after crystal injection (P = 0.038 and P = 0.03, respectively, versus controls), whereas PMN linear densities showed 2 peaks, one at 4 hours and the other 24 hours. The exudate histamine content peaked 6 hours after crystal injection, when mast cell linear densities were minimal in the membranes, suggesting mast cell degranulation. Conclusion An increase in monocyte/macrophage and mast cell densities in the membrane preceded the PMN influx in the pouch membrane and exudate, suggesting that mast cells may be involved in the early phase of MSU crystal,induced inflammation, at least in this rat model. [source] In situ study of growth and dissolution kinetics of ammonium oxalate monohydrate single crystals from aqueous solutions containing cationic impuritiesCRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2007K. Sangwal Abstract The results of an in situ investigation of the effect of four different bi- and trivalent cations (Fe(III), Cu(II), Mn(II) and Cr(III)) on the displacement velocity of individual growth steps on the (110) face of ammonium oxalate monohydrate crystals as a function of supersaturation are described and discussed. It was observed that: (1) at a particular temperature of pure solutions and solutions containing impurities, the velocity v of movement of the [110] growth steps is always greater than that of the [111] steps, (2) fluctuations in the velocity of individual growth steps occur in all solutions containing similar concentrations of different impurities, (3) the value of kinetic coefficient , for growth steps decreases with an increase in the concentration ci of Cu(II) impurity, but that for dissolution steps does not depend on ci; moreover, the value of kinetic coefficient , for growth steps is higher than that of dissolution steps, and (4) in the presence of Mn(II) and Cr(III) impurities, the kinetic coefficient , for dissolution steps is several times greater than that for growth steps. The results are explained from the standpoint of Kubota-Mullin model of adsorption of impurities at kinks in the steps and the stability of dominating complexes present in solutions. Analysis of the results revealed that: (1) the effectiveness of different impurities in inhibiting growth increases in the order: Fe(III), Cu(II), Mn(II), and Cr(III), and this behavior is directly connected with the stability and chemical constitution of dominating complexes in saturated solutions, (2) fluctuations in the velocity of growth steps is associated with the effectiveness of an impurity for adsorption; the stronger the adsorption of an impurity, the higher is the fluctuation in step velocity v, and (3) depending on the nature of the impurity, the kinetic coefficient for the dissolution steps can remain unchanged or can be higher than that of the growth steps. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] REVIEW: Management of gout: beyond allopurinolINTERNAL MEDICINE JOURNAL, Issue 8 2010N. W. McGill Abstract The basic concepts of the pathogenesis and management of gout have not altered for many years. Monosodium urate monohydrate crystals drive the disease and identification of these crystals is required for certain diagnosis. In contrast, our understanding of the mediators of gouty inflammation, the appropriate target serum urate concentration during treatment, the drugs available and the best ways to use those drugs have all advanced in recent years and will be the focus of this review. [source] Cellular characterization of the gouty tophus: A quantitative analysisARTHRITIS & RHEUMATISM, Issue 5 2010Nicola Dalbeth Objective To characterize the cellular architecture of the tophus and to determine the presence of cytokines implicated in the initiation and resolution of gouty inflammation. Methods Sixteen fixed, paraffin-embedded, uninfected tophus samples were surgically obtained from 12 patients with microscopically proven gout and were analyzed by quantitative immunohistochemistry. The number of cells present in the corona and fibrovascular zones of the tophus was analyzed by Genmod mixed models analysis. Results Numerous CD68+ mononucleated and multinucleated cells were present within the corona zone. Mast cells were identified in all tophus samples and at similar densities throughout the corona and fibrovascular zones. In contrast, neutrophils were rarely observed. Plasma cells were present in very high numbers within the corona zone. The overall number of CD20+ B cells was much lower. However, in 6 of 12 patients (50%), at least 1 B cell aggregate was present in the fibrovascular zone. Large numbers of cells expressing interleukin-1, (IL-1,) were observed in the corona zone. Transforming growth factor ,1 (TGF,1),expressing mononucleated cells were also identified. The number of CD68+ cells correlated with the number of cells expressing IL-1, (r = 0.691, P = 0.009) and the number expressing TGF,1 (r = 0.518, P = 0.04). Conclusion The tophus represents a complex and organized chronic inflammatory tissue response to monosodium urate monohydrate crystals involving both innate and adaptive immune cells. The coexpression of IL-1, and TGF,1 suggests that both proinflammatory and antiinflammatory factors present within the tophus contribute to a cycle of chronic inflammation, attempted resolution, and tissue remodeling. [source] Induction of triggering receptor expressed on myeloid cells 1 in murine resident peritoneal macrophages by monosodium urate monohydrate crystalsARTHRITIS & RHEUMATISM, Issue 2 2006Yousuke Murakami Objective Triggering receptor expressed on myeloid cells 1 (TREM-1) is a cell surface molecule that was recently identified on monocytes and neutrophils. TREM-1 has been implicated in the early inflammatory responses induced by microbes, but its pathophysiologic role in nonmicrobial inflammation remains unknown. In the present study, we investigated the role of TREM-1 in acute inflammation induced by monosodium urate monohydrate (MSU) crystals. Induction of TREM-1 expression by MSU crystal,stimulated murine resident peritoneal macrophages and infiltrating leukocytes in a murine air-pouch model of crystal-induced acute inflammation was determined. The biologic role of TREM-1 in crystal-induced cytokine production by resident peritoneal macrophages was also investigated. Methods TREM-1 expression by resident peritoneal macrophages and infiltrating leukocytes in a murine air-pouch model was determined by quantitative real-time polymerase chain reaction, Western blot analysis, and flow cytometry. Cytokine production by resident peritoneal macrophages after incubation with MSU crystals in the presence or absence of an anti,TREM-1 agonist antibody was determined by enzyme-linked immunosorbent assay. Results TREM-1 expression by resident peritoneal macrophages was significantly induced after stimulation with the crystals. Maximum expression of TREM-1 transcripts and protein occurred at 1 and 4 hours after exposure to the crystals, respectively. Costimulation of resident peritoneal macrophages with MSU crystals and an anti,TREM-1 agonist antibody synergistically increased the production of both interleukin-1, and monocyte chemotactic protein 1 compared with stimulation with the crystals alone. MSU crystals also induced TREM-1 expression in infiltrating leukocytes in a murine air-pouch model of crystal-induced acute inflammation. Conclusion These findings suggest that rapid induction of TREM-1 expression on resident peritoneal macrophages and neutrophils by MSU crystals may contribute to the development of acute gout through enhancement of inflammatory responses. [source] Rapid induction of peroxisome proliferator,activated receptor , expression in human monocytes by monosodium urate monohydrate crystalsARTHRITIS & RHEUMATISM, Issue 1 2003Tohru Akahoshi Objective Peroxisome proliferator,activated receptor , (PPAR,) is a member of the nuclear hormone receptor superfamily and functions as a key regulator of lipid and glucose metabolism, atherosclerosis, and inflammatory responses. This study was undertaken to evaluate the biologic role of PPAR, in self-limiting episodes of acute gouty arthritis. To do this, we investigated PPAR, expression by monosodium urate monohydrate (MSU) crystal,stimulated monocytes, and we studied the effects of PPAR, ligands on crystal-induced acute inflammation. Methods PPAR, expression by MSU crystal,stimulated human peripheral blood mononuclear cells was determined by reverse transcription,polymerase chain reaction and immunostaining. Expression of CD36 on monocytes was detected by flow cytometric analysis. The effects of PPAR, ligands on in vitro crystal-induced cytokine production and on in vivo cellular infiltration during crystal-induced acute inflammation were also investigated. Results MSU crystals rapidly and selectively induced PPAR, expression by monocytes. Gene expression was detected as early as 2 hours, and maximum expression was observed at 4 hours after stimulation. The induced PPAR, was functional, since a PPAR, ligand was able to up-regulate CD36 expression on monocytes. A natural ligand of PPAR,, 15-deoxy-,12,14 -prostaglandin J2 (15deoxy-PGJ2), significantly reduced the crystal-induced production of cytokines by monocytes. Indomethacin inhibited cytokine production only at high concentrations, and an antidiabetic thiazolidinedione (troglitazone) failed to exert significant effects. Administration of troglitazone and 15deoxy-PGJ2 significantly prevented cellular accumulation in a mouse air-pouch model of MSU crystal,induced acute inflammation. Conclusion Rapid induction of PPAR, expression on monocytes by MSU crystals may contribute, at least in part, to the spontaneous resolution of acute attacks of gout. [source] Oxalate ions and calcium oxalate crystal-induced up-regulation of osteopontin and monocyte chemoattractant protein-1 in renal fibroblastsBJU INTERNATIONAL, Issue 3 2006TOHRU UMEKAWA 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. [source] Cell-surface matrix proteins and sialic acids in cell-crystal adhesion; the effect of crystal binding on the viability of human CAKI-1 renal epithelial cellsBJU INTERNATIONAL, Issue 6 2003G. Kramer Objective To investigate the role of sialic acids and cellular matrix proteins as crystal-binding molecules in human calcium-oxalate nephrolithiasis. Materials and methods The well-defined human renal cancer cell line CAKI-1 was used a standard cell culture system. After enzymatic digestion of various cell surface molecules, the binding of ,2,6 (Sambucus nigra, SN-) and ,2,3 (Maackia amurensis, MA)-specific lectins to CAKI-1 cells was analysed. Simultaneously, the effect on adhesion and release of calcium oxalate monohydrate crystals was investigated (eight replicates). The effect of crystal adhesion on cell viability was assessed using Trypan blue exclusion (five replicates). Results Neuraminidase decreased MA-lectin binding of CAKI-1 cells by 39% (P < 0.05) but elevated SN-lectin binding by 812% (P < 0.05). Simultaneously, crystal binding to CAKI-1 cells was increased by 28% (P > 0.05). Pretreatment with collagenase type I, trypsin and dispase II reduced crystal-binding by 61,74% (P < 0.05) with no effect on sialic acid-specific lectin-binding. However, only collagenase type I and dispase (ratio 4 : 1) were also able to release crystals from their receptor-binding sites (P < 0.05). An increase in the number of cell surface-bound crystals correlated significantly with a decrease in cell viability (P < 0.05). Conclusions ,2,3-linked sialic acids protect cells from crystal-binding. Much greater SN-lectin binding associated with only moderately increased crystal binding argues against ,2,6-linked sialic acids as a main target structure of crystals. In contrast, collagen type I, type IV and/or fibronectin seem to be potent crystal-binding molecules on human renal epithelial cells, with collagen type I involved in a potential second step of crystal,cell interaction. [source] |