Vitamin C inhibits crystallization of struvite from artificial urine in the presence of Pseudomonas aeruginosa

ABSTRACT Background: Formation of struvite stones is associated with urinary tract infection by urease-producing bacteria. Biogenic crystal growth in natural and synthetic materials is regulated by the action of inhibitors, ranging from small ions, molecules to large macromolecules. Materials and Methods: We report the dynamics of in vitro crystallization of struvite in presence of vitamin C in synthetic urine using single diffusion gel growth technique. Sodium metasilicate gel of specific gravity 1.05 and the aqueous solution of ammonium dihydrogen phosphate were used as the medium for growing the struvite crystals. The crystallization process was induced by a urease positive struvite stone associated Pseudomonas aeruginosa to mimic the infection leading to stone formation. The grown crystals were characterized by ATR-FTIR and powder XRD. The surface morphology was analysed through FE-SEM for comparison between treatments. Results: We observed decrease in number, dimension, and growth rate of struvite crystals with the increasing concentrations of vitamin C. Crystals displayed well-defined faces and dendritic morphology of struvite in both control and biogenic systems. Conclusion: The results strongly suggest that, vitamin C can modulate the formation of struvite crystals in the presence of uropathogenic bacteria.

Vitamin C inhibits crystallization of struvite from artificial urine in the presence of Pseudomonas aeruginosa.

BACKGROUND: Formation of struvite stones is associated with urinary tract infection by urease-producing bacteria. Biogenic crystal growth in natural and synthetic materials is regulated by the action of inhibitors, ranging from small ions, molecules to large macromolecules. MATERIALS AND METHODS: We report the dynamics of in vitro crystallization of struvite in presence of vitamin C in synthetic urine using single diffusion gel growth technique. Sodium metasilicate gel of specific gravity 1.05 and the aqueous solution of ammonium dihydrogen phosphate were used as the medium for growing the struvite crystals. The crystallization process was induced by a urease positive struvite stone associated Pseudomonas aeruginosa to mimic the infection leading to stone formation. The grown crystals were characterized by ATR-FTIR and powder XRD. The surface morphology was analysed through FE-SEM for comparison between treatments. RESULTS: We observed decrease in number, dimension, and growth rate of struvite crystals with the increasing concentrations of vitamin C. Crystals displayed well-defined faces and dendritic morphology of struvite in both control and biogenic systems. CONCLUSION: The results strongly suggest that, vitamin C can modulate the formation of struvite crystals in the presence of uropathogenic bacteria.

The effect of plum juice on the prevention of struvite calculus formation in vitro.

OBJECTIVES: To evaluate the effect of plum juice on struvite calculus formation in vitro and to explore the effect of plum juice on urease-producing bacteria and urease activity. The compliance of available drugs is low for struvite calculus after surgical treatment and functional food may represent a good choice as an alternative therapy. MATERIALS AND METHODS: Antibacterial activity was assessed using a microdilution antimicrobial susceptibility test. Urease activity was determined by measuring ammonia production. Struvite crystals were induced by Proteus mirabilis in artificial urine with natural and pH-adjusted plum juice. The optical density (OD)(600) and pH of artificial urine were examined, as well the shape and weights of crystals. RESULTS: Natural plum juice showed an antibacterial effect on urease-producing bacteria, whereas the pH-adjusted juice did not. A concentration-dependent inhibition on urease activity was found for both natural and pH-adjusted juice. Natural plum juice at a high concentration of 0.5% showed an obvious inhibition on the increase of OD(600) and pH of the artificial urine, and crystal formation was prevented by up to or more than 8 h, depending on the concentration of juice. Crystal weight in the natural plum juice groups was decreased in a concentration-dependent manner. The pH-adjusted plum juice did not show any effect on OD(600) and pH, although the presence of juice changed the crystal habit, indicating that the juice slowed the growth rate of crystals. CONCLUSIONS: Natural plum juice at high and moderate concentrations prevented the formation of P. mirabilis-induced crystals for up to 8 h in artificial urine. Although pH-adjusted and low-concentration natural juice did not prevent the occurrence of crystals, both types of juice slowed their growth rate.

Microlithiasis: an important cause of "idiopathic" acute pancreatitis?

Microlithiasis is the underlying cause in a significant proportion of patients with "idiopathic" acute pancreatitis. The mechanism appears to be a relative deficiency of phosphatidylcholine in bile, with fast and extensive cholesterol crystallization as a result. Diagnosis of microlithiasis by microscopic detection of cholesterol crystals in bile is important and should lead to appropriate therapy (cholecystectomy, endoscopic sphincterotomy or ursodeoxycholic acid maintenance therapy).

[Raising of the treatment efficacy of renal colic and prophylaxis of acute calculous pyelonephritis in patient with ureterolithiasis]. / Pidvyshchennia efektyvnosti likuvannia nyrkovoï kol'ky ta zapobihannia vynyknenniu hostsroho kal'kul'oznoho piielonefrytu u khvorykh na ureterolitiaz.

In 116 patients with renal colic, caused by stones of ureters, conservative treatment with application of hyperbaric oxygenation (HBO) was conducted. Under the influence of oxygenotherapy during 3 days obstruction of the urinary tracts in all patients had disappeared as well as acute urostasis, clinic symptoms of the renal colic, progress of an acute infectious-inflammatory process stopped, complications were eliminated. Echo-positive subjects had disappeared from kidneys, in one patient renal calculus had dissolved, in 5--calculi had reduced in size and fragmentated, in 9--had not changed. In 108 patients the ureters had freed from calculi, in 8--calculi had reduced in size and migrated in distal direction.

[The study of the efficacy of the microsurgical trauma-proof suture materials in biliary duct surgery]. / Izuchenie éffektivnosti primeneniia mikrokhirurgicheskikh atravmaticheskikh shovnykh materialov v khirurgii zhelchnykh protokov.

Comparative estimation of the native microsurgical atraumatic suture material metallatraum and the foreign threads (prolene and virgin silk) application while the biliobiliary and biliodigestive anastomoses formation was done in experiment. Most favourable tissue reaction was noted using monolithic threads prolene and metallatraum. Metallatraum thread is the most resistant one to the calculi deposition on it. The silk thread application in biliary ducts surgery is not indicated.

Therapy in gout.

The effective management of patients with gout is outlined. The treatment of the acute attack, the prevention of recurrent episodes, and the dissolution of tophi, when present, are generally straightforward and associated with relatively few complications. Patients with a resistant acute attack, with extensive tophaceous deposition, or with allergy or toxicity to any of the standard drugs, present more complex treatment decisions. All agents must be used in an individualized manner for each patient with appropriate concern for risks as well as for benefit.

[Pancreatic lithogenesis]. / Lithogenèse pancréatique.

The first lesion of chronic calcifying pancreatitis (CCP), the most frequent form of chronic pancreatitis is the formation in the ducts of plugs build up of protein and calcium carbonate which are at the origin of pancreatic calculi. Pancreatic juice is supersaturated in calcium carbonate. A novel protein, the pancreatic stone protein (PSP) has been purified from human pancreatic juice and its amino-acid composition has been determined. It is biosynthesized in the acinar cell as well as enzymes. PSP prevents the formation of calcium carbonate crystals in a supersaturated solution. Its secretion is decreased in patients presenting with CCP. It is proposed that this decrease plays an important part in the pathogenesis of CCP.

[Chronic calcifying pancreatitis, pancreatic calculi. New data]. / Pancréatite chronique calcifiante, lithiase pancréatique. Données nouvelles.

There are two different forms of chronic pancreatitis: one is obstructive pancreatitis which results from a pre-existing obstacle (usually a tumour or a scar) and the other, much more frequent, is chronic calcifying pancreatitis which seems to begin with the formation of precipitates in acini and ducts, later transformed into stones and calcifications made up of calcium carbonate, and therefore is a pancreatic lithiasis. Since the pancreatic juice is supersaturated in calcium carbonate, the presence of an inhibitor of crystallization must be postulated. This has now been identified as a 13500 daltons molecular weight protein: the pancreatic stone protein secreted by the acinar cells. This protein is decreased in chronic calcifying pancreatitis irrespective of its origin (alcoholic, hereditary, hypercalcaemic, tropical, idiopathic), although its reduction is unrelated to any of these aetiological factors. Chronic alcohol consumption may encourage calcium stone formation possibly by disturbing the cholinergic regulation of pancreatic secretion, with decrease in citrate secretion (citrate is a chelator of calcium) and increase in enzyme secretion. The diagnostic and therapeutic implications of these findings are already obvious.

Inhibition of calcium oxalate crystallisation by pentosan polysulphate in control subjects and stone formers.

In vitro studies showed that sodium pentosan polysulphate (SPP) is an active inhibitor of calcium oxalate (CaOx) crystal growth and agglomeration and that it acts by increasing the negative zeta potential on the surface of CaOx crystals. Oral administration of SPP to control subjects, recurrent stone formers and patients with primary hyperoxaluria resulted in an overall increase of 8% (P less than 0.01) in the polyanionic inhibition of CaOx crystallisation in urine as measured by the zeta potential. SPP could provide a novel approach to the medical prevention of recurrent CaOx stone disease.

[Legal requirements, quality criteria, therapeutic interest and dietetics of mineral waters: study of the case of the natural mineral water of Evian]. / Exigences légales, critères de qualité intérêt thérapeutique et diététique des eaux minérales: étude du cas de l'eau minérale naturelle d'Evian.

The considerable increase in mineral water sales as a daily drink reflects more or less the continued confidence in spa treatments, and this has caused the Public Authorities to set up very strict regulations in this field. We explain the main provisions of these regulations, compare mineral water with ordinary drinking water and complete this report with a study on the representative case of Evian Mineral water since it is the most exported water in the world. We emphasize the key points regarding the origin of the water which must be very well protected, its mineralization leading to its part played in dietetics and daily consumption, its use in spas and the research on its therapeutic effects, its bottling and the controls enabling its original high quality to be maintained. The conclusion reviews the motivations for the mineral water consumer: taste, quality, favorable effects on health. These motivations linked together have a varying importance according to the persons or situations involved. They result in precise requirements to be met by the producing companies in three fields: quality, advertising, credibility and scientific research.

[Inhibitory action of diphosphonate on the development of pancreatic concrements (experiment with EHDP (author's transl)]. / Diphosphonat als Inhibitor einer Konkrementbildung im Pankreas (Tierversuche mit AHDP).

The application of the diphosphonate EHDP (ethane-I-hydroxy-I,I-diphosphonate) prior to the commencement of a calciphylactic experiment (SELYE) inhibits the interstitial calcification and fixation of apatite in the pancreas of female rats (dosage: 20 mgEHDP i. p. per 150 g body mass). Thus the inhibitory potency of EHDP on soft tissue calcification is confirmed. Previously, on the basis of experimental results, a therapeutic administration of this substance in the field of clinical pancreatology could not be derived because the most of human intraductal calculi is composed of calcium carbonate.

Dietary treatment of idiopathic hypercalciuria.

Eighty-eight urinary tract stone formers (74 men) with idiopathic hypercalciuria were treated by dietary calcium restriction alone. Short-term control of hypercalciuria was achieved in only 27 patients and all but 12 eventually escaped control. Failure of control was twice as likely in patients with severe hypercalciuria. Almost all patients lived in a hard water area. In such areas at least, attempts to control hypercalciuria by diet alone are likely to fail and early introduction of additional treatment is advisable. In most severe hypercalciurics, such treatment should be introduced from the start.