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3.
Sci Rep ; 7(1): 9444, 2017 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-28842629

RESUMEN

The reduced number of circulating stem/progenitor cells that is found in chronic kidney disease (CKD) patients may contribute to impaired angiogenic repair and decreased capillary density in the heart. Cell therapy with bone marrow-derived cells (BMDCs) has been shown to induce positive effects on the microvasculature and cardiac function, most likely due to secretion of growth factors and cytokines, all of which are present in the conditioned medium (CM); however, this is controversial. Here we showed that treatment with BMDC or CM restored vascular density and decreased the extent of fibrosis in a rat model of CKD, the 5/6 nephrectomy. Engraftment and differentiation of exogenous BMDCs could not be detected. Yet CM led to the mobilization and infiltration of endogenous circulating cells into the heart. Cell recruitment was facilitated by the local expression of pro-inflammatory factors such as the macrophage chemoattractant protein-1, interleukin-6, and endothelial adhesion molecules. Consistently, in vitro assays showed that CM increased endothelial adhesiveness to circulating cells by upregulating the expression of adhesion molecules, and stimulated angiogenesis/endothelial tube formation. Overall, our results suggest that both treatments exert vasculoprotective effects on the heart of uremic rats by stimulating endogenous repair mechanisms.


Asunto(s)
Células de la Médula Ósea/fisiología , Trasplante de Médula Ósea , Vasos Coronarios/fisiología , Medios de Cultivo Condicionados/metabolismo , Riñón/fisiología , Insuficiencia Renal Crónica/terapia , Uremia/terapia , Animales , Quimiocina CCL2/metabolismo , Modelos Animales de Enfermedad , Humanos , Interleucina-6/metabolismo , Riñón/cirugía , Masculino , Neovascularización Fisiológica , Ratas , Ratas Sprague-Dawley , Insuficiencia Renal Crónica/inmunología , Uremia/inmunología , Remodelación Vascular
4.
Crit Care Med ; 45(10): 1616-1624, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28640024

RESUMEN

OBJECTIVES: Acute-on-chronic liver failure is associated with numerous consecutive organ failures and a high short-term mortality rate. Molecular adsorbent recirculating system therapy has demonstrated beneficial effects on the distinct symptoms, but the associated mortality data remain controversial. DESIGN: Retrospective analysis of acute-on-chronic liver failure patients receiving either standard medical treatment or standard medical treatment and molecular adsorbent recirculating system. Secondary analysis of data from the prospective randomized Recompensation of Exacerbated Liver Insufficiency with Hyperbilirubinemia and/or Encephalopathy and/or Renal Failure trial by applying the recently introduced Chronic Liver Failure-criteria. SETTING: Medical Departments of University Hospital Muenster (Germany). PATIENTS: This analysis was conducted in two parts. First, 101 patients with acute-on-chronic liver failure grades 1-3 and Chronic Liver Failure-C-Organ Failure liver subscore equals to 3 but stable pulmonary function were identified and received either standard medical treatment (standard medical treatment, n = 54) or standard medical treatment and molecular adsorbent recirculating system (n = 47) at the University Hospital Muenster. Second, the results of this retrospective analysis were tested against the Recompensation of Exacerbated Liver Insufficiency with Hyperbilirubinemia and/or Encephalopathy and/or Renal Failure trial. INTERVENTIONS: Standard medical treatment and molecular adsorbent recirculating system. MEASUREMENTS AND MAIN RESULTS: Additionally to improved laboratory variables (bilirubin and creatinine), the short-term mortality (up to day 14) of the molecular adsorbent recirculating system group was significantly reduced compared with standard medical treatment. A reduced 14-day mortality rate was observed in the molecular adsorbent recirculating system group (9.5% vs 50.0% with standard medical treatment; p = 0.004), especially in patients with multiple organ failure (acute-on-chronic liver failure grade 2-3). Concerning the affected organ system, this effect of molecular adsorbent recirculating system on mortality was particularly evident among patients with increased kidney, brain, or coagulation Chronic Liver Failure-C-Organ Failure subscores. Subsequent reanalysis of the Recompensation of Exacerbated Liver Insufficiency with Hyperbilirubinemia and/or Encephalopathy and/or Renal Failure dataset with adoption of the Chronic Liver Failure-classification resulted in similar findings. CONCLUSIONS: Molecular adsorbent recirculating system treatment was associated with an improved short-term survival of patients with acute-on-chronic liver failure and multiple organ failure. Among these high-risk patients, molecular adsorbent recirculating system treatment might bridge to liver recovery or liver transplantation.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada/mortalidad , Insuficiencia Hepática Crónica Agudizada/terapia , Desintoxicación por Sorción , Insuficiencia Hepática Crónica Agudizada/clasificación , Bilirrubina/análisis , Creatinina/análisis , Femenino , Humanos , Hiperbilirrubinemia/terapia , Masculino , Persona de Mediana Edad , Puntuaciones en la Disfunción de Órganos , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Retrospectivos
5.
PLoS One ; 12(4): e0175529, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28403210

RESUMEN

BACKGROUND: The primary therapeutic goals in the treatment of liver injury are to support liver regeneration or bridge the gap to liver transplantation (LT). Molecular adsorbent recirculating system (MARS) therapy has shown beneficial effects for specific symptoms of liver failure; however, general survival advantages have not yet been demonstrated. AIM: We studied the effects of MARS therapy compared to standard medical treatment (SMT) in two patient cohorts: in patients with an acute liver injury and in those with graft dysfunction (GD). METHODS: We report on our experience over a 6.5-year period with 73 patients treated with SMT or with SMT and MARS (MARS group). In total, 53 patients suffered from acute liver injury in their native liver without a preexisting liver disease (SMT: n = 31, MARS: n = 22), and 20 patients showed a severe GD after LT (SMT: n = 10, MARS: n = 10). RESULTS: The entire cohort was predominantly characterized by hemodynamically and respiratorily stable patients with a low hepatic encephalopathy (HE) grade and a model of end-stage liver disease (MELD) score of 20.57 (MARS) or 22.51 (SMT, p = 0.555). Within the MARS group, the median number of extracorporeal therapy sessions was four (range = 3-5 sessions). Independent of the underlying etiology, MARS improved the patients' bilirubin values in the short term compared to SMT alone. In patients with acute liver injury, this response was sustained even after the end of MARS therapy. By contrast, the majority of patients with GD and an initial response to MARS therapy experienced worsened hyperbilirubinemia. No differences in 28-day mortality were observed with respect to acute liver injury (MARS 5.3% (95% CI: 0-15.3); SMT 3.3% (95% CI: 0-9.8), p = 0.754) or GD (MARS 20.0% (95% CI: 0-44.7), SMT 11.1% (95% CI: 0-31.7), p = 0.478). CONCLUSIONS: Although it did not improve 28-day mortality, MARS therapy improved the short-term response in patients with acute liver injury as well as in those with GD. In cases of acute hepatic injury, the use of MARS therapy resulted in the sustained stabilization of liver function and improved liver regeneration. A short-term response to MARS may predict the future course of the disease.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/terapia , Rechazo de Injerto/terapia , Adulto , Anciano , Bilirrubina/sangre , Estudios de Casos y Controles , Enfermedad Hepática Inducida por Sustancias y Drogas/sangre , Femenino , Rechazo de Injerto/sangre , Humanos , Hígado/patología , Regeneración Hepática , Trasplante de Hígado , Masculino , Persona de Mediana Edad , Desintoxicación por Sorción , Resultado del Tratamiento
7.
PLoS One ; 11(8): e0160871, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27575819

RESUMEN

BACKGROUND: This retrospective, multicenter study aimed to reveal risk predictors for mortality in the intensive care unit (ICU) as well as survival after ICU discharge in patients with acute myeloid leukemia (AML) requiring treatment in the ICU. METHODS AND RESULTS: Multivariate analysis of data for 187 adults with AML treated in the ICU in one institution revealed the following as independent prognostic factors for death in the ICU: arterial oxygen partial pressure below 72 mmHg, active AML and systemic inflammatory response syndrome upon ICU admission, and need for hemodialysis and mechanical ventilation in the ICU. Based on these variables, we developed an ICU mortality score and validated the score in an independent cohort of 264 patients treated in the ICU in three additional tertiary hospitals. Compared with the Simplified Acute Physiology Score (SAPS) II, the Logistic Organ Dysfunction (LOD) score, and the Sequential Organ Failure Assessment (SOFA) score, our score yielded a better prediction of ICU mortality in the receiver operator characteristics (ROC) analysis (AUC = 0.913 vs. AUC = 0.710 [SAPS II], AUC = 0.708 [LOD], and 0.770 [SOFA] in the training cohort; AUC = 0.841 for the developed score vs. AUC = 0.730 [SAPSII], AUC = 0.773 [LOD], and 0.783 [SOFA] in the validation cohort). Factors predicting decreased survival after ICU discharge were as follows: relapse or refractory disease, previous allogeneic stem cell transplantation, time between hospital admission and ICU admission, time spent in ICU, impaired diuresis, Glasgow Coma Scale <8 and hematocrit of ≥25% at ICU admission. Based on these factors, an ICU survival score was created and used for risk stratification into three risk groups. This stratification discriminated distinct survival rates after ICU discharge. CONCLUSIONS: Our data emphasize that although individual risks differ widely depending on the patient and disease status, a substantial portion of critically ill patients with AML benefit from intensive care.


Asunto(s)
Unidades de Cuidados Intensivos/estadística & datos numéricos , Leucemia Mieloide Aguda/mortalidad , Síndrome de Respuesta Inflamatoria Sistémica/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Mortalidad , Análisis Multivariante , Puntuaciones en la Disfunción de Órganos , Estudios Retrospectivos , Factores de Riesgo , Centros de Atención Terciaria , Adulto Joven
8.
Haematologica ; 101(10): 1208-1215, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27470601

RESUMEN

Patients undergoing intensive chemotherapy for acute myeloid leukemia are at high risk for bacterial infections during therapy-related neutropenia. However, the use of specific antibiotic regimens for prophylaxis in afebrile neutropenic acute myeloid leukemia patients is controversial. We report a retrospective evaluation of 172 acute myeloid leukemia patients who received 322 courses of myelosuppressive chemotherapy and had an expected duration of neutropenia of more than seven days. The patients were allocated to antibiotic prophylaxis groups and treated with colistin or ciprofloxacin through 2 different hematologic services at our hospital, as available. The infection rate was reduced from 88.6% to 74.2% through antibiotic prophylaxis (vs without prophylaxis; P=0.04). A comparison of both antibiotic drugs revealed a trend towards fewer infections associated with ciprofloxacin prophylaxis (69.2% vs 79.5% in the colistin group; P=0.07), as determined by univariate analysis. This result was confirmed through multivariate analysis (OR: 0.475, 95%CI: 0.236-0.958; P=0.041). The prophylactic agents did not differ with regard to the microbiological findings (P=0.6, not significant). Of note, the use of ciprofloxacin was significantly associated with an increased rate of infections with pathogens that are resistant to the antibiotic used for prophylaxis (79.5% vs 9.5% in the colistin group; P<0.0001). The risk factors for higher infection rates were the presence of a central venous catheter (P<0.0001), mucositis grade III/IV (P=0.0039), and induction/relapse courses (vs consolidation; P<0.0001). In conclusion, ciprofloxacin prophylaxis appears to be of particular benefit during induction and relapse chemotherapy for acute myeloid leukemia. To prevent and control drug resistance, it may be safely replaced by colistin during consolidation cycles of acute myeloid leukemia therapy.


Asunto(s)
Profilaxis Antibiótica/métodos , Ciprofloxacina/administración & dosificación , Colistina/administración & dosificación , Leucemia Mieloide Aguda/complicaciones , Neutropenia/prevención & control , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Antineoplásicos/efectos adversos , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/prevención & control , Catéteres Venosos Centrales/efectos adversos , Estudios de Cohortes , Femenino , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Mucositis/complicaciones , Neutropenia/tratamiento farmacológico , Estudios Retrospectivos , Adulto Joven
9.
PLoS One ; 11(5): e0154993, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27152520

RESUMEN

BACKGROUND: High-cut-off hemodialysis (HCO-HD) can effectively reduce high concentrations of circulating serum free light chains (sFLC) in patients with dialysis-dependent acute kidney injury (AKI) due to multiple myeloma (MM). Therefore, the aim of this study was to analyze renal recovery in a retrospective single-center cohort of dialysis-dependent MM patients treated with either conventional HD (conv. HD) or HCO-HD. METHODS AND RESULTS: The final cohort consisted of 59 patients treated with HCO-HD (n = 42) or conv. HD (n = 17). A sustained sFLC response was detected in a significantly higher proportion of HCO-HD patients (83.3%) compared with conv. HD patients (29.4%; p = 0.007). The median duration of sFLC required to reach values <1000 mg/l was 14.5 days in the HCO-HD group and 36 days in the conv. HD group. The corresponding rates of renal recovery were 64.3% and 29.4%, respectively (chi-squared test, p = 0.014). Multivariate regression and decision tree analysis (recursive partitioning) revealed HCO-HD (adjusted odds ratio [OR] 6.1 [95% confidence interval (CI) 1.5-24.5], p = 0.011) and low initial uric acid values (adjusted OR 1.3 [95%CI 1.0-1.7], p = 0.045) as independent and paramount variables associated with a favorable renal outcome. CONCLUSIONS: In summary, the results from this retrospective case-control study suggest in addition to novel agent-based chemotherapy a benefit of HCO-HD in sFLC removal and renal outcome in dialysis-dependent AKI secondary to MM. This finding was especially pertinent in patients with low initial uric acid values, resulting in a promising renal recovery rate of 71.9%. Further prospective studies are warranted.


Asunto(s)
Mieloma Múltiple/fisiopatología , Terapia de Reemplazo Renal , Anciano , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
Am J Hematol ; 86(12): E61-4, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21898532

RESUMEN

There have been several attempts to improve treatment and outcome of patients with primary mediastinal B-cell lymphoma (PMBL) and Burkitt's lymphoma (BL). In recent years, chemotherapy dose intensification and the addition of rituximab have led to a remarkable progress and have developed into integral parts of treatment for both entities of lymphoma [1­4]. Here, we report our monocenter results of a high-dose methotrexate based alternating regimen with rituximab (B-ALL/NHL 2002 protocol) in 15 patients with PMBL and 28 patients with sporadic BL. Since the early 1980s, protocols of GMALL have been continuously adapted and in the meantime they have become reference treatment for BL and B-ALL in Germany. The latest changes comprised the additional use of rituximab, standardized G-CSF support,implementation of high-dose cytarabine, intrathecal triple therapy,and age-adjusted stratification. Furthermore, we additionally amended supportive care with palifermin as it reduced severity and prevalence of mucositis [5].


Asunto(s)
Anticuerpos Monoclonales de Origen Murino/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma de Burkitt/tratamiento farmacológico , Linfoma de Células B/tratamiento farmacológico , Neoplasias del Mediastino/tratamiento farmacológico , Metotrexato/administración & dosificación , Adulto , Factores de Edad , Anciano , Anticuerpos Monoclonales de Origen Murino/efectos adversos , Anticuerpos Monoclonales de Origen Murino/uso terapéutico , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Linfoma de Burkitt/patología , Estudios de Cohortes , Femenino , Factor 7 de Crecimiento de Fibroblastos/uso terapéutico , Humanos , Linfoma de Células B/patología , Masculino , Neoplasias del Mediastino/patología , Metotrexato/efectos adversos , Metotrexato/uso terapéutico , Persona de Mediana Edad , Mucositis/inducido químicamente , Mucositis/prevención & control , Estadificación de Neoplasias , Rituximab , Análisis de Supervivencia , Adulto Joven
11.
J Nucl Med ; 48(12): 1932-9, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18006618

RESUMEN

UNLABELLED: Hybrid PET/CT was compared with PET alone in the staging and restaging of patients with Ewing tumor to assess the benefit of the combined imaging technique. METHODS: A total of 163 (18)F-FDG PET/CT studies performed in 53 patients (age: range, 4-38 y; median, 16.5 y) with histopathologically confirmed Ewing tumor were evaluated retrospectively. All PET/CT studies included low-dose CT for attenuation correction; in 91 examinations, additional diagnostic chest CT was performed. PET and CT data were assessed independently by 2 nuclear medicine physicians and 2 radiologists, respectively. Finally, both datasets were fused by use of software and analyzed by all 4 reviewers (consensus reading). Each lesion was scored with a 5-point scale. Biopsy, imaging, or clinical follow-up served as a standard of reference. Receiver operating characteristic (ROC) analyses were performed to evaluate PET and PET/CT performance characteristics. To measure the abilities to detect and correctly localize tumor foci, localization ROC (L-ROC) curves were generated for PET. RESULTS: A total of 609 lesions were detected by PET alone. The hybrid PET/CT technique resulted in a change of score in 160 of these lesions (26%): higher scores in 23 lesions (4%) and lower scores in 137 lesions (23%). In 49 lesions detected by PET (8%), the localization had to be changed after image fusion. Additionally, 124 (21%) more lesions were found by PET/CT than by PET alone, resulting in a total of 733 lesions. As determined by lesion-based analysis, the sensitivity, specificity, and accuracy of PET were 71%, 95%, and 88%, respectively; the corresponding values for the hybrid PET/CT technique were 87%, 97%, and 94% (P < 0.0001). The areas under the curve in the ROC analysis were 0.82 for PET and 0.92 for PET/CT (P < 0.0001), and that in the L-ROC analysis was 0.66 for PET. CONCLUSION: PET/CT is significantly more accurate than PET alone for the detection and localization of lesions and improves staging for patients with Ewing tumor. The hybrid technique is superior to PET alone in terms of sensitivity, specificity, and accuracy, mainly because of the detection of new lesions.


Asunto(s)
Neoplasias Óseas/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Sarcoma de Ewing/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Neoplasias Óseas/patología , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Estadificación de Neoplasias , Curva ROC , Sarcoma de Ewing/patología
12.
Dent Mater ; 23(12): 1521-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17353046

RESUMEN

OBJECTIVES: The aim of this study was to develop a molecular-based structural model of human teeth after fluoridation with a commonly used amine fluoride, which is highly significant for understanding the effectiveness of topical fluoridation. METHODS: This multi method study used XPS, MAS-NMR and Raman-spectroscopy measurements in order to analyze powdered synthetic hydroxylapatite (HAp), powdered human enamel samples and human enamel pieces treated with amine fluoride (Elmex) fluid) in vitro. RESULTS: The results lead to a complete structural characterization of the fluoridation products. A three layer composition of calcium hydroxide, calcium fluoride and an apatite species was identified. SIGNIFICANCE: The top surface CaF(2) layer acts as a fluoride reservoir and covers a layer of antimicrobial effective Ca(OH)(2). Ca(OH)(2) is a well-known therapeutic agent. However, up to now Ca(OH)(2) has not been described as a reaction product after topical fluoridation. Below the Ca(OH)(2) layer an acid resistant apatite species (FAp) was detected which reached directly into the bulk enamel HAp species. The three layer composition identified helps to understand the influence of fluoride application in the pathogenic mechanisms of tooth decay. Each component in this newly suggested structure model has a specific function, which explains how topical fluoridation of enamel reduces dental caries and influences its pathogenic mechanisms.


Asunto(s)
Aminas/farmacocinética , Cariostáticos/farmacocinética , Esmalte Dental/metabolismo , Fluoruros Tópicos/farmacocinética , Fluoruros/farmacocinética , Modelos Químicos , Apatitas , Fluoruro de Calcio , Hidróxido de Calcio , Esmalte Dental/química , Diaminas , Durapatita , Microanálisis por Sonda Electrónica , Humanos , Espectroscopía de Resonancia Magnética , Espectrometría Raman , Desmineralización Dental/metabolismo
13.
Dent Mater ; 22(10): 934-41, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16364427

RESUMEN

OBJECTIVES: The chemical and physical properties of the dual curing luting composites RelyX Unicem (3M ESPE) and Bifix (VOCO) were analyzed with regard to their elemental composition, surface morphology and polymerization reaction. The bonding of both materials to hydroxyapatite (HAp) was studied. METHODS: The main components were analyzed by XPS and EDX. The minor components were identified with ICP-OES. Moreover, the morphology was examined by SEM and the polymerization reaction products were investigated using GPC. XPS was also applied to study the bonding mechanisms to HAp. RESULTS: The inorganic product particles consist of an Al-Si-Na-glass network, which incorporates radiopaque strontium and barium for Bifix and strontium and lanthanum for RelyX Unicem. RelyX Unicem contains about 10% fluoride and 2% Ca(OH)(2), whereas Bifix comprises 2% fluoride. After polymerization, reaction products of 10(5)-10(6)g/mol were identified with RelyX Unicem. Both products contain mono- and oligomeric compounds. The reaction with HAp generates calcium atoms with a reduced binding energy. They act as an electron acceptor and show chemical interaction between the composite and HAp. With RelyX Unicem 86% of the calcium atoms reacted, compared to 65% with Bifix. SIGNIFICANCE: The intense chemical interaction of RelyX Unicem with HAp seems to be relevant to clinical aspects and explains the mechanical product properties. After setting, a polymer was found with RelyX Unicem but only monomeric/oligomeric products were identified at the surface of Bifix.


Asunto(s)
Resinas Compuestas/química , Recubrimiento Dental Adhesivo , Durapatita/química , Cementos de Resina/química , Silicatos de Aluminio/análisis , Análisis del Estrés Dental , Fluoruros/análisis , Enlace de Hidrógeno , Incrustaciones , Ensayo de Materiales , Metales/análisis , Metacrilatos/análisis , Microscopía Electrónica de Rastreo , Transición de Fase , Fosfatos/análisis , Análisis Espectral/métodos , Sulfatos/análisis , Propiedades de Superficie
14.
Dent Mater ; 21(8): 731-8, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15935463

RESUMEN

OBJECTIVES: The chemical and physical properties of white ProRoot MTA were analyzed in the bulk and at the surface and compared with two common Portland cements types CEM1 and CEM2. METHODS: The main components were analyzed by X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray analysis (EDX), and the minor constituents were identified with inductively coupled plasma optical emission spectroscopy (ICP-OES). Moreover, the setting of the different cements was studied: the chemical composition of the surface of both powder and bound cement was investigated by XPS and the morphological changes were examined by scanning electron microscopy (SEM). RESULTS: In ProRoot MTA, the amount of gypsum is approximately half of that of the Portland cements. ProRoot MTA consists of less toxic heavy metals (Cu, Mn, Sr), less chromophores (Fe3+), and less Al-species, but contains about 2 at % Bi. In contrast to Portland cements, ProRoot MTA contains about 2 at.% Bi. In all three products, the amount of sulfur at the surface in the bound cements was 3 times higher than in the powder, indicating that in terms of the kinetics of the hardening reaction, a sulfate action mechanism prolongs the setting time. The Portland cements are composed of particles with a wide range of size, whereas ProRoot MTA showed a uniform and smaller particle size. SIGNIFICANCE: With regard to chemical and physical surface and bulk properties, ProRoot MTA cannot simply be substituted by the cheaper Portland cement. Both products are similar but not equal and exhibit marked differences.


Asunto(s)
Compuestos de Aluminio/química , Compuestos de Calcio/química , Cementos Dentales/química , Óxidos/química , Materiales de Obturación del Conducto Radicular/química , Silicatos/química , Bismuto/química , Sulfato de Calcio/química , Cobre/química , Combinación de Medicamentos , Microanálisis por Sonda Electrónica , Compuestos Férricos/química , Humanos , Manganeso/química , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Polvos , Espectrometría por Rayos X , Estroncio/química , Compuestos de Azufre/química , Propiedades de Superficie
15.
Anticancer Drugs ; 16(1): 101-6, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15613912

RESUMEN

The cytotoxicity of a new platinum compound Pt1 [2,9-dimethyl-4,7-diphenyl-1,10-phenanthrolinedichloroplatin(II)] and six polyoxometalates (POM1-6) on two neuroblastoma cell lines (SHEP-SF and KCN) and an Ewing's Sarcoma cell line (CADO-ES-1) was studied. Cisplatin [cis-diamminedichloroplatinum(II)] and carboplatin [cis-diammine(cyclobutanedicarboxylato)platinum(II)] were used as reference agents. Using MTT tests, the cytotoxicity (LD50: lethal doses 50%) of the compounds were measured at different concentrations. After 72 h exposure, the LD50 data for the platinum-containing substances ranged between 4.47 x 10(-6) and 1.91 x 10(-4) M. The SHEP-SF cell line displayed the highest sensitivity to cisplatin. The novel platinum agent Pt1 had a similar cytotoxic effect to the reference agent cisplatin. Both cisplatin and Pt1 were more cytotoxic than carboplatin. The POMs reduced cell viability compared to untreated cells at concentrations between 8.4 x 10(-7) and 3.47 x 10(-5) M. POM1 ([(CH3)4N]2Na6.5(NH4)2[SnII1.5(WO2(OH))0.5(WO2)2(SbW9O33)2] x 32H2O) was the most effective polyoxoanion with a mean LD50 value of 8.83 x 10(-6) M in the three cell lines tested. With CADO-ES-1 and KCN cells, POM1 was found to be more effective than the platinum compounds cisplatin, carboplatin and Pt1.


Asunto(s)
Antineoplásicos/farmacología , Supervivencia Celular/efectos de los fármacos , Compuestos de Tungsteno/farmacología , Carboplatino , Línea Celular Tumoral , Cisplatino/farmacología , Humanos , Polímeros/farmacología , Pruebas de Toxicidad
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