Active and passive microrheology with large tracers in hard colloids.

The dynamics of a tracer particle in a bath of quasi-hard colloidal spheres is studied by Langevin dynamics simulations and mode coupling theory (MCT); the tracer radius is varied from equal to up to seven times larger than the bath particles radius. In the simulations, two cases are considered: freely diffusing tracer (passive microrheology) and tracer pulled with a constant force (active microrheology). Both cases are connected by linear response theory for all tracer sizes. It links both the stationary and transient regimes of the pulled tracer (for low forces) with the equilibrium correlation functions; the velocity of the pulled tracer and its displacement are obtained from the velocity auto-correlation function and the mean squared displacement, respectively. The MCT calculations give insight into the physical mechanisms: At short times, the tracer rattles in its cage of neighbours, with the frequency increasing linearly with the tracer radius asymptotically. The long-time tracer diffusion coefficient from passive microrheology, which agrees with the inverse friction coefficient from the active case, arises from the transport of transverse momentum around the tracer. It can be described with the Brinkman equation for the transverse flow field obtained in extension of MCT, but cannot be recovered from the MCT kernel coupling to densities only. The dynamics of the bath particles is also studied; for the unforced tracer the dynamics is unaffected. When the tracer is pulled, the velocity field in the bath follows the prediction of the Brinkman model, but different from the case of a Newtonian fluid.

Dynamics and friction of a large colloidal particle in a bath of hard spheres: Langevin dynamics simulations and hydrodynamic description.

The analysis of the dynamics of tracer particles in a complex bath can provide valuable information about the microscopic behavior of the bath. In this work, we study the dynamics of a forced tracer in a colloidal bath by means of Langevin dynamics simulations and a theory model within continuum mechanics. In the simulations, the bath is comprised of quasihard spheres with a volume fraction of 50% immersed in a featureless quiescent solvent, and the tracer is pulled with a constant small force (within the linear regime). The theoretical analysis is based on the Navier-Stokes equation, where a term proportional to the velocity arises from coarse-graining the friction of the colloidal particles with the solvent. As a result, the final equation is similar to the Brinkman model, although the interpretation is different. A length scale appears in the model, k_{0}^{-1}, where the transverse momentum transport crosses over to friction with the solvent. The effective friction coefficient experienced by the tracer grows with the tracer size faster than the prediction from Stokes's law. Additionally, the velocity profiles in the bath decay faster than in a Newtonian fluid. The comparison between simulations and theory points to a boundary condition of effective partial slip at the tracer surface. We also study the fluctuations in the tracer position, showing that it reaches diffusion at long times, with a subdiffusive regime at intermediate times. The diffusion coefficient, obtained from the long-time slope of the mean-squared displacement, fulfills the Stokes-Einstein relation with the friction coefficient calculated from the steady tracer velocity, confirming the validity of the linear response formalism.

Effect of chloride on the one step electrochemical treatment of an industrial textile wastewater with tin dioxide anodes. The case of trichromy procion HEXL.

The resulting solutions from the cotton fabrics dyeing using the trichromy Procion HEXL, with NaCl as electrolyte, were electrochemically treated. These dyes have two azo groups as chromophores and two monochlorotriazinic groups as reactive groups in their structure. The combined oxidation/reduction at 125 mA cm-2 in a filter-press cell without compartment separation was carried out using an anode of Ti/SnO2-Sb-Pt and a cathode of stainless steel. This procedure has been effective in previous experiments using sulphate as electrolyte. A significant decrease in total organic carbon (TOC), chemical oxygen demand (COD), and total nitrogen (TN) was obtained. Moreover, the process took place efficiently. The average oxidation state (AOS) and the carbon oxidation state (COS) data confirmed the presence of stable oxidized intermediates in the electrolysed solution. The chromatography and the UV-Visible spectrophotometry assays indicated that full decolourisation is obtained at a loaded charge of around 0.81 Ah L-1 which is associated with an electrical energy per order (EEO) of 1.20 kWh m-3.

Prevalencia y características clínicas de la apnea del sueño en una población de mujeres diagnosticadas de cáncer de mama / Prevalence and clinical characteristics of sleep apnea in a population of women diagnosed with breast cancer

Objetivo: a pesar del interés creciente en la asociación entre apnea de sueño (AS) y cáncer, apenas existen estudios que investiguen tumores concretos. Nuestro objetivo fue analizar la prevalencia y características clínicas de la AS en mujeres con cáncer de mama (CM). Métodos: estudio piloto transversal. Se incluyen consecutivamente 83 mujeres entre 18 - 65, años diagnosticadas por primera vez de CM. En todos los casos se realizó un cuestionario clínico y una poligrafía respiratoria domiciliaria. La AS se definió como un índice de apneas-hipopneas (IAH) ≥5, y el síndrome de apneas-hipopneas del sueño (SAHS) como la asociación de un IAH ≥5 y excesiva somnolencia diurna (ESD, Epworth >10). Resultados: la media (DE) de edad fue de 48,8 (8,8) años, el índice de masa corporal (IMC) de 27,4 (5,4) y el 50,6% eran postmenopáusicas. La prevalencia de AS fue del 51,8% (43 casos), y la mediana de IAH de 5,1 (RIQ 2 - 9,4). De las 43 pacientes con AS, 32 presentaron un IAH 5 - 14,9 y 11 IAH ≥15. La prevalencia de SAHS fue del 10,8% (9 casos). Comparadas con las mujeres sin AS, aquellas con AS presentaron más ronquido, pero no hubo diferencias en otros síntomas relacionados con el sueño. En el análisis multivariado, la edad y las variables antropométricas, pero no la ESD, se asociaron independientemente a la AS. Conclusión: la prevalencia de AS es elevada en mujeres de mediana edad diagnosticadas de CM, aunque la mayoría no presentan ESD ni otras características diferenciales. La edad y la obesidad fueron predictores de AS en esta población

Objective: Despite growing interest in the association between sleep apnea and cancer, there are hardly any studies that research specific tumors. Our objective was to analyze the prevalence and characteristics of sleep apnea in women with breast cancer. Methods: A transversal pilot study. 83 women between the ages of 18 and 65 diagnosed with breast cancer for the first time were included consecutively. All participants completed a clinical questionnaire and underwent home respiratory polygraphy. Sleep apnea was defined as an apnea-hypopnea index (AHI) ≥5 and sleep apnea-hypopnea syndrome (SAHS) was defined as the association between an AHI ≥5 and excessive daytime sleepiness (EDS, Epworth >10). Results: The average (SD) age was 48.8 (8.8) years old, the body mass index (BMI) was 27.4 (5.4) and 50.6% were postmenopausal. The prevalence of sleep apnea was 51.8% (43 cases) and the average AHI was 5.1 (IQR: 2 - 9.4). Of the 43 patients with sleep apnea, 32 had an AHI between 5 and 14 and 11 had an AHI ≥15. The prevalence of SAHS was 10.8% (9 cases). Compared to women without sleep apnea, those with the disease snored more, but there were no differences in other sleep-related symptoms. In the multivariate analysis, age and anthropometric variables, but not EDS, were independently associated with sleep apnea. Conclusion: The prevalence of sleep apnea is higher in middle-aged women diagnosed with breast cancer, although the majority do not present with EDS or other distinguishing characteristics. Age and obesity were predictors for sleep apnea in this population

[The alexithymia questionnaire for children (AQC): Psychometric properties in a sample of 105 adolescents hospitalized in an adolescent psychiatric department]. / Le questionnaire d'alexithymie pour enfants (QAE) : étude sur une population clinique de 105 adolescents hospitalisés en pédopsychiatrie.

OBJECTIVE: The 20-item Toronto Alexithymia Scale (TAS-20) is the most widely used measure of alexithymia in non-clinical or clinical populations. The TAS-20 evaluates three dimensions of the alexithymia construct: the difficulty identifying feelings (DIF), the difficulty describing feelings (DDF) and externally oriented thinking (EOT). The TAS-20 is also used in adolescents or children, and the psychometric properties of the scale have not been systematically evaluated in these populations. Recently several studies have shown systematic age differences in the factor structure and a decrease of the quality of the measurement with age. Notably, low reliability measured by the Cronbach α coefficient has been found for the EOT factor. Taking into account the limitations of the TAS-20 in pre-adult populations the Alexithymia Questionnaire for Children (AQC), an adaptation of the TAS-20, has been proposed by a reformulation of the TAS-20 items (Rieffe et al., 2006). Two studies in healthy children found satisfactory psychometric properties with the three-factor structure demonstrating adequate parameters in the confirmatory factorial analyses (CFA). In the two studies low reliabilities of the EOT factor were reported, and recent studies in adolescents using the TAS-20 found that a two-factor model (DDF, DIF) had a better fit than the original three-factor model. Thus, the aim of the present study was firstly to verify the psychometric properties of the AQC in a sample of adolescents presenting various psychiatric disorders and secondly to test the adequacy of the bi- or tridimensional model of the scale. METHOD: One hundred and five adolescents (27 males, 78 females) with a mean age of 15.06 years (sd=1.55, range: 12-18 years) were hospitalized in the adolescent psychiatric department of the Erasme Hospital (Bruxelles, Belgium) for various psychiatric disorders. The main diagnoses were: adjustment disorder (n=56, 53.5%), mood or anxiety disorders (n=17, 16.2%), impulse control disorder (n=11, 10.5%). The subjects completed the French version of the AQC. CFA were done testing the adequacy of the three or two-factor structure of the scale. Two indices were considered: the normed χ2 (ratio of χ2 and degrees of freedom) and the root mean square error of approximation (RMSEA). The values for acceptable fit were normed χ2<3 and RMSEA<0.05. Cronbach α were also calculated. RESULTS: Fit indices for the three-factor model were respectively 1.165 and 0.0303 for the normed χ2 and RMSEA. For the two-factor model, the values were respectively 0.819 and 0. Thus, these two well-fitting models were compared using the χ2-difference test, which indicated a significantly better fit for the two-factor model over the three-factor model (χ2-difference=151.447, delta df=114, P<0.05). The values of the Cronbach α coefficients were respectively 0.72, 0.75, 0.18 for DIF, DDF and EOT subscales. Moreover, the values of the Cronbach α coefficients were respectively 0.71 and 0.83 for the full scale and the scale without the EOT items. CONCLUSION: The Alexithymia Questionnaire for Children had satisfactory psychometric properties found in a sample of adolescent psychiatric inpatients. Taking into account firstly the superiority of the two-factor model over the classical three-factor model and secondly the low value of the Cronbach α for the EOT factor, it is proposed to use only the twelve-item scale by excluding the EOT items.

Mastopatía cirrótica / Mastopathy caused by liver cirrhosis

Introducción. Se han descrito diferentes causas de patología inflamatoria mamaria. En ocasiones, existe la necesidad de plantear un diagnóstico diferencial y descartar un carcinoma mamario. Caso clínico. Mujer de 63 años con antecedentes de cirrosis. Presenta mama izquierda aumentada de tamaño, eritematosa y con edema con fóvea. Tras tratamiento antibiótico no existe mejoría. La ecografía, mamografía y biopsia resultan negativas. Finalmente, se plantea el proceso como una descompensación de la cirrosis, a pesar de su manifestación unilateral. Tras tratamiento con diuréticos, observamos una resolución del proceso. Conclusión. El diagnóstico diferencial en patología de la mama en ocasiones resulta muy dificultoso. Además, existen patologías que requieren un manejo rápido dado su mal pronóstico. El caso presentado muestra cómo en la búsqueda de un diagnóstico se deben considerar todas las causas posibles, pero además pensar en los antecedentes médicos del paciente ya que pueden influir o ser la causa del proceso (AU)

Introduction. Various causes of inflammatory breast disease have been described and sometimes a differential diagnosis is required to rule out breast carcinoma. Case report. A 63-year-old woman with a history of cirrhosis had an enlarged left breast, erythema, and edema. Antibiotic treatment produced no improvement. The results of ultrasound, mammography and biopsy were negative. Finally, the process was diagnosed as a decompensation of cirrhosis, despite its unilateral manifestation. The process resolved with diuretic therapy. Conclusion. The differential diagnosis of breast disease is sometimes extremely difficult. Some diseases require rapid treatment due to their poor prognosis. The case presented here illustrates how every possible cause of the entity and the patient's medical history should be considered because they could influence or even cause the process (AU)

Evaluación y manejo de los hematomas de la vaina de los rectos. Análisis de nuestra experiencia / Evaluation and management of rectus sheath hematomas. Analysis of our experience

El hematoma de la vaina de los rectos es una entidad clínica infrecuente aunque parece que su incidencia está aumentando. Los factores más frecuentemente relacionados con su aparición son la tos, los traumatismos abdominales y la anticoagulación. El diagnóstico no es fácil y requiere una prueba de imagen en la mayoría de los casos. El tratamiento suele ser conservador. La cirugía se reserva en los casos de inestabilidad hemodinámica o cuando el hematoma está infectado

Rectus sheath hematoma is an uncommon clinical entity although it appears that its incidence is increasing. Factors most frequently associated are cough, abdominal trauma, and anticoagulation. The diagnosis is not easy and a test image is required in the majority of cases. The treatment is usually conservative. Surgery must be reserved in cases of hemodynamic instability or when hematoma is infected

[Predictors of the use of the early invasive strategy in women with non-ST-elevation acute coronary syndrome]. / Predictores del uso de la estrategia invasiva precoz en mujeres con síndrome coronario agudo sin elevación de ST.

OBJECTIVE: To identify determinants associated to an early invasive strategy in women with acute coronary syndromes without ST elevation (NSTE-ACS). DESIGN: A retrospective cohort study was made. Crude and adjusted analysis of the performance of the early invasive strategy using logistic regression. SETTING: Coronary Units enrolled in 2010 - 2011 in the ARIAM-SEMICYUC registry. PATIENTS: A total of 440 women with NSTE-ACS were studied. Sixteen patients were excluded due to insufficient data, together with 58 patients subjected to elective coronary angiography (> 72 h). VARIABLES ANALYZED: Demographic parameters, coronary risk factors, previous medication, comorbidity. Clinical, laboratory, hemodynamic and electrocardiographic data of the episode. RESULTS: Women treated conservatively were of older age, had oral anticoagulation, diabetes, previous coronary lesions, and heart failure (p<0.005), increased baseline bleeding and ischemic risk (p=0.05) and a higher heart rate upon admission (p<0.05). After adjustment, only age > 80 years (OR 0.48, 95% CI 0.27 to 0.82, p=0.009), known coronary lesions (OR 0.47, 95% CI 0.26-0.84, p=0.011), and heart rate (OR 0.98, 95% CI 0.97-0.99, p=0.003) were independently associated to conservative treatment. Smoking (OR 2.50, 95% CI 1.20 to 5.19, p=0.013) and high-risk electrocardiogram (OR 2.96, 95% CI 1.72 to 4.97, p<0.001) were associated to the early invasive strategy. The exclusion of early deaths (<24 h) did not alter these results. CONCLUSIONS: In women with NSTE ACS, smoking and a high-risk electrocardiogram upon admission were independent factors associated to the early invasive strategy. Previous coronary lesions, age > 80 years and increased heart rate were independent factors associated to conservative treatment.

[Effectiveness and safety of triple antiaggregation in patients undergoing coronary intervention]. / Efectividad y seguridad de la "triple antiagregación" en pacientes sometidos a intervencionismo coronario.

OBJECTIVE: To evaluate glycoprotein IIb/IIIa inhibitors (GPIIb/IIIa inhibitors) effectiveness and safety in patients with non-ST segment elevation acute coronary syndrome (NSTEACS) or stable coronary disease referred for percutaneous coronary revascularization pre-treated with aspirin and thienopyridines by means of a systematic review. SOURCE OF DATA: Electronic search using Medline, Embase, Pascal, Cochrane Library and ISI Proceedings and manual review of the articles found. STUDY SELECTION: We included randomized controlled trials that assessed the clinical efficacy (risk of death or infarction) and safety (bleeding and thrombocytopenia) of GPIIb/IIIa inhibitors in patients pretreated with thienopyridines. DATA EXTRACTION: Data were obtained by duplicate. RESULTS: Nine randomized controlled trials (8,604 patients) were included. Addition of GPIIb/ IIIa inhibitors reduced the risk of death or myo-cardial infarction at 30 days in those trials that included patients with NSTEACS (RR 0.67; 95%CI 0.56-0.80) but not in studies that excluded NSTEACS patients (RR 1.07; 95%CI 0.75-1.53) (p test of interaction 0.0175), As a counterpart, GPIIb/ IIIa inhibitors increased the risk of bleeding and thrombocytopenia. CONCLUSIONS: Use of GPIIb/IIIa inhibitors reduces the risk of adverse cardiac events in NSTEACS patients pre-treated with aspirin and thienopyridines but increases the risk of severe bleeding and thrombocytopenia. Its utilization in stable coronary patients does not seem justified.

Efectividad y seguridad de la «triple antiagregación» en pacientes sometidos a intervencionismo coronario / Effectiveness and safety of triple antiaggregation in patients undergoing coronary intervention

Objetivo. Evaluar, mediante una revisión sistemática de la literatura, la efectividad y seguridad de los antagonistas IIb/IIIa (AGIIb/IIIa) en pacientes con síndrome coronario agudo sin elevación de ST (SCASEST) o cardiopatía coronaria estable sometidos a revascularización percutánea pretratados con aspirina y tienopiridinas. Fuente de datos. Búsqueda electrónica en Medline a través de PubMed, Embase, Pascal, Cochrane Library e ISI Proceedings y revisión manual de las referencias bibliográficas recuperadas. Selección de estudios. Se incluyeron en la revisión aquellos ensayos clínicos aleatorizados que evaluaban el efecto de los AGIIbIIIa en pacientes pretratados con tienopiridinas que incluían información sobre el riesgo a medio plazo de muerte/infarto y/o hemorragia/trombopenia. Extracción de datos. Los datos se obtuvieron por duplicado. Resultados. Se incluyeron 9 ensayos aleatorizados (8.604 pacientes). El tratamiento con AGIIb/IIIa redujo el riesgo de muerte o infarto a los 30 días en los ensayos que incluían pacientes con SCASEST (RR: 0,67; IC95%: 0,56-0,80), pero no en los ensayos que excluían a dichos pacientes (RR 1,07; IC95% 0,75-1,53) (p test de interacción 0,0175). En contrapartida, la adición de un AGIIb/ IIIa aumentó el riesgo hemorrágico y de trombopenia. Conclusiones. El uso de AGIIb/IIIa en pacientes con SCASEST sometidos a intervencionismo coronario, tratados con aspirina y tienopiridinas, reduce el riesgo de eventos cardiovasculares adversos, aunque aumenta el riesgo de trombopenia y complicaciones hemorrágicas. Su utilización en pacientes coronarios estables no parece justificada

Objective. To evaluate glycoprotein IIb/IIIa inhibitors (GPIIb/IIIa inhibitors) effectiveness and safety in patients with non-ST segment elevation acute coronary syndrome (NSTEACS) or stable coronary disease referred for percutaneous coronary revascularization pre-treated with aspirin and thienopyridines by means of a systematic review. Source of data. Electronic search using Medline, Embase, Pascal, Cochrane Library and ISI Proceedings and manual review of the articles found. Study selection. We included randomized controlled trials that assessed the clinical efficacy (risk of death or infarction) and safety (bleeding and thrombocytopenia) of GPIIb/IIIa inhibitors in patients pretreated with thienopyridines. Data extraction. Data were obtained by duplicate. Results. Nine randomized controlled trials (8,604 patients) were included. Addition of GPIIb/ IIIa inhibitors reduced the risk of death or myo-cardial infarction at 30 days in those trials that included patients with NSTEACS (RR 0.67; 95%CI 0.56-0.80) but not in studies that excluded NSTEACS patients (RR 1.07; 95%CI 0.75-1.53) (p test of interaction 0.0175), As a counterpart, GPIIb/ IIIa inhibitors increased the risk of bleeding and thrombocytopenia. Conclusions. Use of GPIIb/IIIa inhibitors reduces the risk of adverse cardiac events in NSTEACS patients pre-treated with aspirin and thienopyridines but increases the risk of severe bleeding and thrombocytopenia. Its utilization in stable coronary patients does not seem justified

[Superior vena cava occlusion syndrome in a patient receiving total parenteral nutrition for short bowel syndrome]. / Síndrome de oclusión de la vena cava superior en paciente con nutrición parenteral total por síndrome de intestino corto.

The use of venous access devices has been increased in recent years. The administration of nutrients parenterally is one of the indications for use of these devices. However, these are not free of complications, with infection and obstruction of the devices being the most common. One fo the less frequent but most feared complications, especially in those patients in whom the parenteral access route is the only access for the supply of nutrients, is that of thrombosis of the large veins. This study presents, along with the bibliographical review of the matter, the diagnostic and therapeutic procedures undertaken in a case of thrombosis of the superior vena cava, in a patient with total parenteral nutrition in the home, due to a short bowel syndrome.

[The administration of intermittent outpatient total parenteral nutrition via a subcutaneous reservoir]. / Administración de una nutrición parenteral total intermitente ambulatoria mediante reservorio subcutáneo.

The development of artificial nutrition has made it possible to maintain the nutritional condition and survival of patients with large intestinal resections along with therapeutic support in certain pathological processes. As such patients have become aware of their potential and the prolonged life expectancy offered, they have increased their demands for enhanced comfort and independence. The experience with a patient with short gut syndrome following quasi-total intestinal resection due to necrosis, and with another with post-esophagocoloplasty necrosis, and the administration of intermittent outpatient total parenteral nutrition through a subcutaneous reservoir in both cases, enabled us to appreciate the advantages of the reservoir in administration of the nutrition. The ease of administration, reduced risk of infection and the positive psychological effect seen in these patients, enabled to lead a "practically normal" life, all vindicate the use of this method.

[Low-residue diets supplemented with fermentable fiber. Effect on experimental colonic anastomosis]. / Dietas de bajo residuo suplementadas con fibra fermentable. Efecto sobre las anastomosis cólicas experimentales.

Presentation of an experimental study comparing the scarring of colic anastomoses performed in Wistar rats fed with three different types of diet: a standard laboratory diet, an enteral low-residue diet and a low-residue diet supplemented with fermentable fibre in short chain fatty acids (pectin). Scarring in the group fed with the standard laboratory diet showed greater anastomotic complications, and the microscopic appearance was more inflamed. The administration of low-residue diets reduced the level of complications, but also reduced the concentration of collagen and the parietal rupture tension. The addition of pectin to a low-residue diet maintained the complications at a low level, and also significantly increased the pressure parameters and the collagen concentration.

69,XXX karyotype in a malformed liveborn female. Maternal origin of triploidy.

A liveborn female with a 69,XXX karyotype and clinical features of triploidy syndrome is reported. Main phenotypical features are: intrauterine growth retardation, hypotonicity, micrognathism, low-set ears, ocular anomalies, syndactyly and atrophy of the cerebral cortex and corpus callosum. Study of chromosomal heteromorphisms revealed that triploidy might have arisen through fertilization of a diploid ovum by a haploid sperm (diginy).