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1.
Phys Rev Lett ; 129(1): 012502, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35841540

RESUMEN

A near-threshold proton resonance in ^{11}B at E_{ex}=11.44±0.04 MeV is observed via the reaction ^{10}Be(d,n)^{11}Be→^{10}Be+p in inverse kinematics, measured with a beam of the radioactive isotope ^{10}Be. The resonance energy at E_{res}=211(40) keV is consistent with a proton signal observed by Ayyad et al. in the ß-delayed proton decay of ^{11}Be. By comparison to a distorted wave Born approximation calculation, a 0.27(6) spectroscopic factor is extracted and a tentative (ℓ=0) character is assigned for this resonance. The significant cross section in the proton-transfer (d,n) reaction, as well as the observation of its proton-decay signal, point to the threshold-resonance character of this state. The position of this state, its structure, and strong coupling to the s-wave continuum represent an ideal case to study quantum near-threshold many-body dynamics of unstable states. The presence of this state is an important step toward understanding the excessively large beta-delayed proton-decay branch of ^{11}Be.

2.
Vascul Pharmacol ; 122-123: 106583, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31437530

RESUMEN

The purpose of the present study was to investigate whether SNF472, the hexasodium salt of myo-inositol hexaphosphate (IP6 or phytate): 1. Inhibits induced calcification in cultured aortic valve interstitial cells (VIC) as an in vitro model of aortic valve stenosis and 2. Whether inhibition is different in VIC obtained from healthy and calcified aortic valves. VIC from healthy (n = 5) and calcified (n = 7) human aortic valves were seeded in basic growth medium, osteogenic differentiation medium alone, or in osteogenic medium with SNF472 (3, 10, and 30 µM) and cultivated for 3 weeks. Calcification was quantified spectrophotometrically after Alizarin Red staining. In VIC from calcified valves, a complete inhibition of calcification was observed with SNF472 concentrations of 10 and 30 µM (p < .01), significantly stronger than in VIC from healthy valves. When SNF472 was added to VIC after 1 week in osteogenic medium, 30 and 100 µM SNF472 inhibited the progression of ongoing calcification by 81 and 100% (p < .01), respectively. The same concentrations of SNF472 given after 2 weeks reduced calcification by 35 and 40% respectively (not significant). SNF472 inhibited both the formation and the progression of calcification with the strongest effect in VIC from calcified valves.


Asunto(s)
Estenosis de la Válvula Aórtica/tratamiento farmacológico , Válvula Aórtica/efectos de los fármacos , Calcio/metabolismo , Ácido Fítico/farmacología , Válvula Aórtica/metabolismo , Válvula Aórtica/patología , Estenosis de la Válvula Aórtica/metabolismo , Estenosis de la Válvula Aórtica/patología , Estudios de Casos y Controles , Células Cultivadas , Cristalización , Progresión de la Enfermedad , Humanos , Factores de Tiempo
3.
Br J Clin Pharmacol ; 84(12): 2867-2876, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30280390

RESUMEN

AIMS: SNF472 is a calcification inhibitor being developed for the treatment of cardiovascular calcification in haemodialysis (HD) and in calciphylaxis patients. This study investigated the safety, tolerability and pharmacokinetics (PK) of intravenous (IV) SNF472 in healthy volunteers (HV) and HD patients. METHODS: This is a first-time-in-human, double-blind, randomized, placebo-controlled Phase I study to assess the safety, tolerability and PK of SNF472 after ascending single IV doses in HV and a single IV dose in HD patients. A pharmacodynamic analysis was performed to assess the capability of IV SNF472 to inhibit hydroxyapatite formation. RESULTS: Twenty HV and eight HD patients were enrolled. The starting dose in HV was 0.5 mg kg-1 and the dose ascended to 12.5 mg kg-1 . The dose selected for HD patients was 9 mg kg-1 . Safety analyses support the safety and tolerability of IV SNF472 in HD patients and HV. Most treatment-emergent adverse events were mild in intensity. No clinically significant effects were observed on vital signs or laboratory tests. PK results were similar in HD patients and HV and indicate a lack of significant dialysability. Pharmacodynamic analyses demonstrated that SNF472 administration reduced hydroxyapatite crystallization potential in HD patients who received IV SNF472 9 mg kg-1 by 80.0 ± 2.4% (mean ± standard error of the mean, 95% CI, 75.3-84.8) compared to placebo (8.7 ± 21.0%, P < 0.001, 95% CI, -32.4 to 49.7). CONCLUSION: The results from this study showed acceptable safety and tolerability, and lack of significant dialysability of IV SNF472. It is a potential novel treatment for cardiovascular calcification in end-stage renal disease and calciphylaxis warranting further human studies.


Asunto(s)
Fallo Renal Crónico/terapia , Ácido Fítico/efectos adversos , Diálisis Renal/efectos adversos , Calcificación Vascular/prevención & control , Adulto , Anciano , Calcio/metabolismo , Método Doble Ciego , Voluntarios Sanos , Humanos , Fallo Renal Crónico/complicaciones , Masculino , Persona de Mediana Edad , Ácido Fítico/farmacocinética , Ácido Fítico/farmacología
4.
Sci Rep ; 7(1): 6858, 2017 07 31.
Artículo en Inglés | MEDLINE | ID: mdl-28761091

RESUMEN

Cardiovascular calcification (CVC) is a progressive complication of chronic kidney disease and a predictor of CV events and mortality. The use of biomarkers to predict CV risk and activities of potential or current treatment drugs in these patients could have a crucial impact on therapeutic approaches. Our aim was to develop a novel assay for measurement of the rate of calcium phosphate crystallization in human plasma and provide a tool to evaluate the effects of crystallization inhibitors. The efficacy of inhibitors was determined by adding inhibitory compounds (polyphosphates, fetuin-A, sodium thiosulfate or citrate) to control samples. The assay was additionally validated for SNF472, an experimental formulation of phytate being developed for the treatment of calciphylaxis and CVC in patients with end-stage renal disease (ESRD) undergoing hemodialysis (HD). The method was repeatable and reproducible. The plasma crystallization rate was reduced up to 80% in a concentration-dependent manner following treatment with inhibitors in vitro, among which SNF472 was the most potent. This method appears beneficial in evaluating and discriminating between inhibitory activities of compounds such as polyphosphates on calcium phosphate crystallization, which present a novel therapeutic approach to treat CVC in ESRD patients.


Asunto(s)
Calcifilaxia/tratamiento farmacológico , Fosfatos de Calcio/sangre , Plasma/efectos de los fármacos , Animales , Calcifilaxia/sangre , Calcifilaxia/prevención & control , Quelantes del Calcio/farmacología , Quelantes del Calcio/uso terapéutico , Evaluación Preclínica de Medicamentos/métodos , Humanos , Masculino , Plasma/metabolismo , Ratas , Ratas Sprague-Dawley , Espectrofotometría/métodos
5.
R Soc Open Sci ; 3(7): 160177, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27493774

RESUMEN

Human mobility is becoming an accessible field of study, thanks to the progress and availability of tracking technologies as a common feature of smart phones. We describe an example of a scalable experiment exploiting these circumstances at a public, outdoor fair in Barcelona (Spain). Participants were tracked while wandering through an open space with activity stands attracting their attention. We develop a general modelling framework based on Langevin dynamics, which allows us to test the influence of two distinct types of ingredients on mobility: reactive or context-dependent factors, modelled by means of a force field generated by attraction points in a given spatial configuration and active or inherent factors, modelled from intrinsic movement patterns of the subjects. The additive and constructive framework model accounts for some observed features. Starting with the simplest model (purely random walkers) as a reference, we progressively introduce different ingredients such as persistence, memory and perceptual landscape, aiming to untangle active and reactive contributions and quantify their respective relevance. The proposed approach may help in anticipating the spatial distribution of citizens in alternative scenarios and in improving the design of public events based on a facts-based approach.

6.
Eur J Nutr ; 49(6): 321-6, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20108098

RESUMEN

BACKGROUND: Important health benefits have been reported recently to phytate intake. This includes the prevention of pathological calcifications such as renal calculi, dental calculi and cardiovascular calcification, due its action as crystallization inhibitor of calcium salts, and as preventive of cancer. AIM OF STUDY: The aim of this study was to establish a relation between the intake of phytate, through consumption of typical components of the Mediterranean diet (including nuts), and its excretion in urine. METHODS: This study recruited participants from subjects included in a larger trial (PREDIMED) of food habits, that were assigned to one of two diet groups: (1) the Mediterranean diet with low proportion of phytate-rich food group, where participants were asked to maintain their usual diet; and (2) the Mediterranean diet with high proportion of phytate-rich food group, where participants were asked to increase phytate-rich foods in their diet. Phytate intake was assessed on the basis of a food frequency questionnaire. Urinary phytate excretion was determined in 2-h urine samples. RESULTS: The overall phytate consumption of the Mediterranean diet with high proportion of phytate-rich food group (672 +/- 50 mg) was significantly higher than the Mediterranean diet with low proportion of phytate-rich food group (422 +/- 34 mg), representing a 59% difference. Urinary phytate excretion was also significantly higher (54%) in the Mediterranean diet with high proportion of phytate-rich food group (1,016 +/- 70 microg/L) than the Mediterranean diet with low proportion of phytate-rich food group (659 +/- 45 microg/L). CONCLUSIONS: Mediterranean diets high in whole cereals, legumes and nuts compared to Mediterranean diets low in these phytate-rich foods increase the urinary phytate excretion in humans.


Asunto(s)
Dieta Mediterránea , Ácido Fítico/administración & dosificación , Ácido Fítico/orina , Anciano , Calcinosis/prevención & control , Neoplasias Colorrectales/prevención & control , Estudios Transversales , Grano Comestible/química , Fabaceae/química , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nueces/química , Semillas/química , Encuestas y Cuestionarios
7.
J Periodontal Res ; 44(5): 616-21, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18973518

RESUMEN

BACKGROUND AND OBJECTIVE: Dental calculus occurs as a consequence of supersaturation of saliva with respect to calcium phosphates. This mineralization of dental plaque can be delayed by the presence of crystallization inhibitors, such as pyrophosphate or bisphosphonates. Phytate inhibits brushite and hydroxyapatite crystallization and has the potential to prevent dental calculi formation. The aim of the present study was to examine the effects of phytate and zinc, administered in a mouthwash solution, to prevent the formation of dental calculus. MATERIAL AND METHODS: Healthy dental plaque-forming volunteers (n = 25) took part in a randomized, double-blind, three-period crossover clinical study to assess the efficacy of a phytate-containing mouthwash in relation to control and placebo effects. Subjects rinsed their mouths for 1 min, twice each day, with 20 mL of the test solution, without ingestion. Mouthwash efficacy was assessed through quantification of the amounts of calcium, phosphorus and magnesium present in the residues obtained by dental cleaning, performed by a single trained examiner. RESULTS: A good correlation was found among total calcium, magnesium and phosphorus in calcified dental plaque residues, indicating that any of these variables is adequate for evaluating the reduction of plaque crystallization as calcium phosphate. A statistically significant decrease in total calcium, magnesium and phosphorus was found in the phytate-treatment period compared with control and placebo periods, demonstrating the efficacy of the proposed treatment in reducing dental calculus formation. CONCLUSION: The high efficacy of phytate in reducing dental calculus formation suggests that this substance may be an effective treatment for preventing the development of calculus deposits.


Asunto(s)
Antiinfecciosos Locales/uso terapéutico , Cálculos Dentales/prevención & control , Antisépticos Bucales/uso terapéutico , Ácido Fítico/uso terapéutico , Triclosán/uso terapéutico , Adolescente , Adulto , Anciano , Calcio/análisis , Fosfatos de Calcio/antagonistas & inhibidores , Estudios Cruzados , Cristalización , Placa Dental/química , Método Doble Ciego , Durapatita/antagonistas & inhibidores , Femenino , Humanos , Magnesio/análisis , Masculino , Persona de Mediana Edad , Fósforo/análisis , Placebos , Adulto Joven , Zinc/uso terapéutico
10.
Magnes Res ; 19(2): 102-6, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16955721

RESUMEN

Stress and anxiety of university science students (Chemistry) was evaluated in basal conditions and during exams using validated stress and anxiety questionnaires. The relations between the data obtained and various biochemical markers were established. Results showed that the evaluated students did not experience stress increase as a consequence of exams but suffered a significant increase in anxiety. The psychological findings agree with the urinary biomarkers studied. It is known that anxiety is related to partial magnesium reduction associated with a urinary magnesium excretion increase, as observed in the present data. Nevertheless, stress also correlates with a urinary calcium increase which was not detected in the present study.


Asunto(s)
Ansiedad/psicología , Calcio/orina , Magnesio/orina , Estrés Psicológico/psicología , Estudiantes/estadística & datos numéricos , Adolescente , Adulto , Ansiedad/metabolismo , Ansiedad/orina , Calcio/metabolismo , Femenino , Humanos , Magnesio/metabolismo , Masculino , Fósforo/metabolismo , Fósforo/orina , Ciencia , Estrés Psicológico/metabolismo , Estrés Psicológico/orina , Encuestas y Cuestionarios
11.
Pharmazie ; 61(7): 652, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16889078

RESUMEN

In this paper, we present a pilot study of the absorption of myo-inositol hexakisphosphate (InsP6) through the skin in humans. We found that, after topical treatment with a 4% InsP6 rich gel, InsP6 urinary excretion increased 54% compared to the control situation (participants submitted to an InsP6-poor diet for 15 days, n = 6), clearly demonstrating that InsP6 is absorbed through the skin of humans. These results demonstrate the topical application as a suitable administration route of InsP6 in humans.


Asunto(s)
Ácido Fítico/farmacocinética , Absorción Cutánea/fisiología , Administración Tópica , Adulto , Dieta , Femenino , Humanos , Masculino , Ácido Fítico/orina
12.
BMC Urol ; 6: 16, 2006 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-16822299

RESUMEN

BACKGROUND: The use of extracorporeal shock wave lithotripsy (ESWL) to treat calcium oxalate dihydrate (COD) renal calculi gives excellent fragmentation results. However, the retention of post-ESWL fragments within the kidney remains an important health problem. This study examined the effect of various urinary conditions and crystallization inhibitors on the regrowth of spontaneously-passed post-ESWL COD calculi fragments. METHODS: Post-ESWL COD calculi fragments were incubated in chambers containing synthetic urine varying in pH and calcium concentration: pH = 5.5 normocalciuria (3.75 mM), pH = 5.5 hypercalciuria (6.25 mM), pH = 6.5 normocalciuria (3.75 mM) or pH = 6.5 hypercalciuria (6.25 mM). Fragment growth was evaluated by measuring increases in weight. Fragment growth was standardized by calculating the relative mass increase. RESULTS: Calcium oxalate monohydrate (COM) crystals formed on COD renal calculi fragments under all conditions. Under pH = 5.5 normocalciuria conditions, only COM crystals formed (growth rate = 0.22 +/- 0.04 microg/mg x h). Under pH = 5.5 hypercalciuria and under pH = 6.5 normocalciuria conditions, COM crystals and a small number of new COD crystals formed (growth rate = 0.32 +/- 0.03 microg/mg x h and 0.35 +/- 0.05 microg/mg x h, respectively). Under pH = 6.5 hypercalciuria conditions, large amounts of COD, COM, hydroxyapatite and brushite crystals formed (growth rate = 3.87 +/- 0. 34 microg/mg x h). A study of three crystallization inhibitors demonstrated that phytate completely inhibited fragment growth (2.27 microM at pH = 5.5 and 4.55 microM at pH = 6.5, both under hypercalciuria conditions), while 69.0 microM pyrophosphate caused an 87% reduction in mass under pH = 6.5 hypercalciuria conditions. In contrast, 5.29 mM citrate did not inhibit fragment mass increase under pH = 6.5 hypercalciuria conditions. CONCLUSION: The growth rate of COD calculi fragments under pH = 6.5 hypercalciuria conditions was approximately ten times that observed under the other three conditions. This observation suggests COD calculi residual fragments in the kidneys together with hypercalciuria and high urinary pH values may be a risk factor for stone growth. The study also showed the effectiveness of specific crystallization inhibitors in slowing calculi fragment growth.


Asunto(s)
Oxalato de Calcio/química , Cálculos Renales/etiología , Orina/fisiología , Calcio/orina , Oxalato de Calcio/antagonistas & inhibidores , Oxalato de Calcio/farmacología , Ácido Cítrico/farmacología , Cristalización , Difosfatos/farmacología , Humanos , Concentración de Iones de Hidrógeno , Cálculos Renales/química , Cálculos Renales/fisiopatología , Litotricia , Ácido Fítico/farmacología , Recurrencia
13.
J Med Food ; 9(1): 72-6, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16579731

RESUMEN

myo-Inositol hexaphosphate (InsP6) widely occurs in plant seeds. At present, some important benefits of InsP6 for human health have been described. The purpose of this study was to find the best condition for the optimum absorption of orally administered InsP6, evaluated by InsP6 urinary excretion. The influence of different stomach conditions (empty, empty with an alkalinizing agent, and full stomach) on the effects of oral administration of InsP6 and its urinary excretion was investigated in six healthy subjects on an InsP6-poor diet, given 400 mg of calcium/magnesium salt of InsP6 as a single dose. The basal urinary excretion of InsP6 on an InsP6-poor diet (50.91 +/- 15.09 microg) was significantly lower than that found when an InsP6-normal diet was consumed (100.09 +/- 26.42 microg) (P < .05). No differences were observed in the areas under the curve of accumulated excretion at 8 hours among the three different stomach conditions studied, suggesting that the overall InsP6 absorption took place independently of the stomach state (full or fasted) and indicating that the InsP6 absorption also takes place during the intestinal transit. Thus, if InsP6 supplements of vegetal origin are consumed to maintain the optimum InsP6 levels needed for a healthy status, these supplements can be consumed either during or between meals with the same efficacy.


Asunto(s)
Alimentos , Ácido Fítico/farmacocinética , Ácido Fítico/orina , Absorción , Adulto , Dieta , Ayuno , Femenino , Humanos , Absorción Intestinal , Masculino , Persona de Mediana Edad , Ácido Fítico/administración & dosificación
14.
Gastroenterol Hepatol ; 28(7): 365-8, 2005.
Artículo en Español | MEDLINE | ID: mdl-16137468

RESUMEN

INTRODUCTION: Complete preoperative study of the colon is required in the management of colorectal cancer, due to the frequent association of primary colonic neoplasms with colonic adenomas (28%) and/or synchronous carcinomas (5%) of the colon. We present a series of patients who underwent computed tomographic colonography, the indications for this procedure, and the results. PATIENTS AND METHODS: We performed a descriptive prospective study. Between May 2003 and August 2004, 50 computed tomographic colonographies were performed in 50 patients with suspected stenosing colorectal cancer and incomplete conventional colonoscopy. RESULTS: Fifty computed tomographic colonographies were performed. The findings were as follows: three were normal (6%), and in the remainder, one was a false positive for a suspected neoplastic pelvic mass (3.125%) and two were false positives (11.7%) for colonic polyps. Fifty percent of the findings (n = 32) were related to peritoneal metastases and colonic neoplasms. There were 12 technical complications [lack of cleaning of the colon (5), lack of distension (2), little air insufflation (5)]. Patient complications included vegetative manifestations in one (vomiting) and rectal bleeding in another. The overall complication rate was 27.4% (23.4% corresponded to technical complications and the remaining 4% were patient-related). There was no mortality related to the procedure. CONCLUSION: Because computed tomographic colonography is safe, effective and well tolerated by the patient, it should be considered as a technical alternative in the study of stenosing neoplasms of the proximal colon with incomplete colonoscopy. In addition, it allows other associated findings, both intra- and extracolonic, to be obtained and improves the diagnostic and therapeutic management of the patient.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Neoplasias del Colon/diagnóstico por imagen , Colonografía Tomográfica Computarizada , Adenocarcinoma/secundario , Adulto , Anciano , Aire , Pólipos del Colon/diagnóstico por imagen , Reacciones Falso Positivas , Femenino , Hemorragia Gastrointestinal/etiología , Humanos , Insuflación/efectos adversos , Masculino , Persona de Mediana Edad , Neoplasias Peritoneales/secundario , Estudios Prospectivos , Vómitos/etiología
15.
Gastroenterol. hepatol. (Ed. impr.) ; 28(7): 365-368, ago. 2005. ilus, tab
Artículo en Es | IBECS | ID: ibc-039989

RESUMEN

Introducción: El estudio preoperatorio completo del colon es necesario para el tratamiento del cáncer colorrectal, debido a la frecuente asociación de la neoplasia primaria de colon con adenomas colónicos (28%) y/o carcinomas sincrónicos (5%) de colon. El objetivo de este trabajo es presentar nuestra serie de pacientes a los que se ha realizado colonografía tomográfica computarizada, sus indicaciones y sus resultados.Pacientes y métodos: Estudio descriptivo y prospectivo. Entre mayo de 2003 y agosto de 2004, se llevaron a cabo 50 colonografías tomográficas computarizadas en 50 pacientes con sospecha de cáncer colorrectal estenosante y colonoscopia preoperatoria incompleta. Resultados: Se realizaron 50 colonografías tomográficas computarizadas. Los hallazgos fueron los siguientes: 3 de ellas fueron normales (6%) y en las restantes se encontró un falso positivo para masa pelviana sospechosa de neoplasia (3,125%) y 2 falsos positivos (11,7%) para pólipos colónicos. El 50% de los hallazgos (n = 32) estuvo en relación con metástasis peritoneales y neoplasias de colon. Hubo 12 casos de complicación técnica (5 falta de limpieza del colon, 2 falta de distensión, 5 escasa insuflación de aire) y 2 del paciente (1 manifestación vegetativa [vómitos], 1 sangrado rectal). La tasa global de complicaciones fue del 27,4% (el 23,4% debidas a complicaciones técnicas y el 4% restante a los pacientes). No hubo mortalidad relacionada con el procedimiento. Conclusión: La colonografía tomográfica computarizada, por su seguridad, eficacia y buena tolerancia por parte del paciente, debe considerarse una técnica alternativa de estudio del colon proximal ante una neoplasia estenosante con colonoscopia incompleta. Además, permite obtener otros hallazgos asociados, intra y extracolónicos, así como mejorar el manejo diagnóstico y terapéutico del paciente


Introduction: Complete preoperative study of the colon is required in the management of colorectal cancer, due to the frequent association of primary colonic neoplasms with colonic adenomas (28%) and/or synchronous carcinomas (5%) of the colon. We present a series of patients who underwent computed tomographic colonography, the indications for this procedure, and the results. Patients and methods: We performed a descriptive prospective study. Between May 2003 and August 2004, 50 computed tomographic colonographies were performed in 50 patients with suspected stenosing colorectal cancer and incomplete conventional colonoscopy. Results: Fifty computed tomographic colonographies were performed. The findings were as follows: three were normal (6%), and in the remainder, one was a false positive for a suspected neoplastic pelvic mass (3.125%) and two were false positives (11.7%) for colonic polyps. Fifty percent of the findings (n = 32) were related to peritoneal metastases and colonic neoplasms. There were 12 technical complications [lack of cleaning of the colon (5), lack of distension (2), little air insufflation (5)]. Patient complications included vegetative manifestations in one (vomiting) and rectal bleeding in another. The overall complication rate was 27.4% (23.4% corresponded to technical complications and the remaining 4% were patient-related). There was no mortality related to the procedure. Conclusion: Because computed tomographic colonography is safe, effective and well tolerated by the patient, it should be considered as a technical alternative in the study of stenosing neoplasms of the proximal colon with incomplete colonoscopy. In addition, it allows other associated findings, both intra- and extracolonic, to be obtained and improves the diagnostic and therapeutic management of the patient


Asunto(s)
Humanos , Adenocarcinoma , Colonografía Tomográfica Computarizada , Neoplasias del Colon , Adenocarcinoma/secundario , Aire , Pólipos del Colon , Reacciones Falso Positivas , Hemorragia Gastrointestinal/etiología , Insuflación/efectos adversos , Estudios Prospectivos , Neoplasias Peritoneales/secundario , Vómitos/etiología
16.
Br J Dermatol ; 152(5): 1022-5, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15888163

RESUMEN

BACKGROUND: Calcinosis cutis is a disorder caused by abnormal deposits of calcium phosphate in the skin and is observed in diverse disorders. Myo-inositol hexaphosphate (InsP(6)) is a diet-dependent molecule found in all mammalian fluids and tissues, which exhibits an extraordinary capacity as a crystallization inhibitor of calcium salts. OBJECTIVES: To establish the effects of topically administered InsP(6) cream on artificially provoked dystrophic calcifications in soft tissues. METHODS: Fourteen male Wistar rats were randomly assigned into two groups: control and treated groups. Rats were fed with an InsP(6)-free or phytate diet. Plaque formation was induced by subcutaneous injection of 0.1% KMnO(4) solution. From 4 days before plaque induction to the end of the experiment, control rats were treated topically with a standard cream, whereas treated rats were treated with the same cream with 2% InsP(6) or phytate (as sodium salt). Calcification of plaques was allowed to proceed for 10 days. InsP(6) in urine was determined. The plaques were excised and weighed. RESULTS: It was found that when InsP(6) was administered topically through a moisturizing cream (2% InsP(6)-rich), the plaque size and weight were notably and significantly reduced compared with the control group (1.6 +/- 1.1 mg InsP(6)-treated, 26.7 +/- 3.0 mg control). The InsP(6) urinary levels for animals treated with the InsP(6)-enriched cream were considerably and significantly higher than those found in animals treated topically with the cream without InsP(6) (16.96 +/- 4.32 mg L(-1) InsP(6)-treated, 0.06 +/- 0.03 mg L(-1) control). CONCLUSIONS: This demonstrates the important capacity of InsP(6) as a crystallization inhibitor and also demonstrates that it is possible to propose topical use as a new InsP(6) administration route.


Asunto(s)
Calcinosis/prevención & control , Ácido Fítico/uso terapéutico , Enfermedades de la Piel/prevención & control , Administración Cutánea , Animales , Calcinosis/inducido químicamente , Calcinosis/patología , Masculino , Pomadas , Ácido Fítico/orina , Permanganato de Potasio , Ratas , Ratas Wistar , Enfermedades de la Piel/inducido químicamente , Enfermedades de la Piel/patología
17.
Urol Res ; 33(1): 51-6, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15633055

RESUMEN

The main objective of this paper was to study residual lithiasis after extracorporeal shock wave lithotripsy (post-ESWL), with the aim of contributing to the development of effective prophylactic measures. In vivo regrown calcium oxalate monohydrate (COM) post-ESWL residual fragments were studied by stereoscopic microscopy, infrared spectroscopy and scanning electron microscopy with an energy dispersive X-ray analyzer. An in vitro system was also used to study the regrowth of post-ESWL fragments of COM calculi. The regrowth was evaluated as the relative increase in the weight of the fragments. The effects of a calcium oxalate crystallization inhibitor (phytate) were also evaluated. All of the in vivo regrown COM real residual post-ESWL fragments exhibited practically the same internal structural features. The in vitro studies demonstrated that the regrowth of post-ESWL residual fragments, in the absence of crystallization inhibitors, occurred even using normocalciuric/normooxaluric urine and could be detected at 24 h. At 144-240 h, the formation of new COM columnar zones was observed. The presence of 1.5 mg/l of phytate totally blocked the growth process. When hypercalciuric/normooxaluric urine was used, significant amounts of disorganized calcium oxalate dihydrate (COD) crystals were formed. The in vitro regrowth of post-ESWL COM fragments was clearly influenced by the presence of crystallization inhibitors. These data also demonstrate the importance that effective prophylactic therapies could exert on preventing recurrence.


Asunto(s)
Cálculos Renales/patología , Cálculos Renales/terapia , Litotricia , Oxalato de Calcio/química , Cristalización/instrumentación , Cristalografía , Humanos , Técnicas In Vitro , Microscopía Electrónica de Rastreo , Ácido Fítico/farmacología , Orina/química
19.
J Trace Elem Med Biol ; 17(4): 229-34, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15139384

RESUMEN

In this paper the relation between long term consumption of a high dose of sodium phytate and the mineral status of the organism is evaluated in rats. For this purpose, element concentrations (Ca, Mg, Fe, Zn, Mn) were determined in liver, heart, testicle, bone and urine of a second generation of Wistar rats, treated with a phytate free diet (AIN-76A) and with the same diet plus 1% phytate as sodium salt. The most significant differences were observed between bone zinc contents of male and female rats. The zinc content of rats fed a 1% phytate as sodium salt diet resulted clearly lower than that found in no-phytate treated rats. Hence, it is concluded that when up to 1% of phytate as sodium salt is consumed together with an equilibrated purified diet (free of phytate), no decrease in mineral bioavailability is observed in second generation rats, except for an indication of lower zinc availability by lower zinc concentrations in some organs, mainly bone. However, using this purified diet, the zinc concentration in bone resulted around 10 times higher than found in rats fed with a common non purified rat chow.


Asunto(s)
Dieta , Metales/química , Ácido Fítico/farmacocinética , Oligoelementos/análisis , Animales , Disponibilidad Biológica , Huesos/química , Femenino , Hígado/química , Masculino , Metales/metabolismo , Miocardio/química , Distribución Aleatoria , Ratas , Ratas Wistar , Testículo/química , Orina/química
20.
Urol Int ; 72(3): 237-43, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15084770

RESUMEN

BACKGROUND: Phytate as sodium salt has been used at high doses to treat stone-former patients with idiopathic hypercalciuria. The experimental and clinical hypocalciuric effects of dietary fiber have also been assigned to the presence of phytate as calcium-magnesium salt (phytin). As a consequence of the additional interest in phytate due to its capacity as crystallization inhibitor, now a study of the effects of potassium phytate on urinary calcium excretion is presented and compared with the effects caused by other phytate salts. METHODS: To study the effect of calcium-magnesium phytate, 36 Wistar rats (6 groups) were fed with a purified diet in which phytate was practically absent (4068.02 Reference Diet). Three groups were fed with increasing calcium amounts and with the same amount of phytin, each one corresponding to one control group. To study the effects of magnesium-potassium, sodium and potassium phytate salts, 48 Wistar rats (8 groups) were fed with UAR-A04 diet (a standard diet which contains 0.8% of phytin). Two control groups fed with low and high calcium amounts and 6 treated groups were formed. The effect of the dose of potassium phytate on urinary calcium was carried out using 2 additional groups of 6 Wistar rats each one fed with UAR-A04 diet and increasing amounts of potassium phytate. RESULTS: No significant changes in urinary calcium were observed when phytin (calcium-magnesium phytate) was supplied. The urinary calcium was clearly reduced by the three phytate salts assayed (magnesium-potassium, sodium, potassium), but the most significant decrease was noticed when the potassium phytate salt was administered. Phytate administration, independently of the salt or dose used, did not significantly affect the urinary oxalate. CONCLUSION: It can be clearly deduced that the effects of phytate on the urinary parameters, mainly calcium, fundamentally depend on the type of salt used. Thus, the most remarkable effects on urinary calcium reduction were caused by the potassium salt. Obviously, these findings must be confirmed in human studies.


Asunto(s)
Calcio/orina , Ácido Fítico/farmacología , Animales , Masculino , Ratas , Ratas Wistar
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