Novel Zinc(II) Complexes [Zn(atc-Et)2] and [Zn(atc-Ph)2]: In Vitro and in Vivo Antiproliferative Studies.

Cisplatin and its derivatives are the main metallodrugs used in cancer therapy. However, low selectivity, toxicity and drug resistance are associated with their use. The zinc(II) (Zn(II)) thiosemicarbazone complexes [Zn(atc-Et)2] (1) and [Zn(atc-Ph)2] (2) (atc-R: monovalent anion of 2-acetylpyridine N4-R-thiosemicarbazone) were synthesized and fully characterized in the solid state and in solution via elemental analysis, Fourier transform infrared (FTIR), ultraviolet-visible (UV-Vis) and proton nuclear magnetic resonance (¹H NMR) spectroscopy, conductometry and single-crystal X-ray diffraction. The cytotoxicity of these complexes was evaluated in the HepG2, HeLa, MDA-MB-231, K-562, DU 145 and MRC-5 cancer cell lines. The strongest antiproliferative results were observed in MDA-MB-231 and HepG2 cells, in which these complexes displayed significant selective toxicity (3.1 and 3.6, respectively) compared with their effects on normal MRC-5 cells. In vivo studies were performed using an alternative model (Artemia salina L.) to assure the safety of these complexes, and the results were confirmed using a conventional model (BALB/c mice). Finally, tests of oral bioavailability showed maximum plasma concentrations of 3029.50 µg/L and 1191.95 µg/L for complexes 1 and 2, respectively. According to all obtained results, both compounds could be considered as prospective antiproliferative agents that warrant further research.

Speciation analysis of inorganic arsenic in river water by Amberlite IRA 910 resin immobilized in a polyacrylamide gel as a selective binding agent for As(V) in diffusive gradient thin film technique.

In this study, a method is proposed for the selective retention of As(V) using diffusive gradient in thin film (DGT) samplers containing a strongly basic anion exchange resin (Amberlite IRA 910) supported on a polyacrylamide gel. In addition, the total arsenic content is determined by ferrihydrite gel discs. Subsequently, the concentration of As(III) was obtained by determining the difference between the total As and As(V). DGT experiments showed linear accumulation of As(V) (up to 280 ng) until a deployment time of 8 h deployment (R(2) > 0.99). The retention of As(V) was appropriate (97.9-112.3%) between pH 5 and 9. For a solution with an ionic strength ranging from 0.001 to 0.05 mol L(-1), the As(V) uptake ranged from 90-120%. The proposed method was applied for the speciation of arsenic in river water. For the analysis of spiked samples collected at the Furnas stream, the recoveries of total arsenic content ranged between 103.9% and 118.8%. However, the recoveries of As(III) and As(V) were 43.3-75.2% and 147.3-153.4%, respectively. These differences were probably because of the oxidation of As(III) to As(V) during deployments. For spiked samples collected at the Ribeirão Claro, the recoveries of dissolved As(III), As(V) and As(T) were 103.1%, 108.0% and 106.3%, respectively. Thus, the DGT technique with Amberlite IRA 910 resin as the binding phase can be employed for the in situ redox speciation of inorganic arsenic.

Functional silencing is initiated and maintained in immature anti-insulin B cells.

Mechanisms of B cell tolerance act during development in the bone marrow and periphery to eliminate or restrict autoreactive clones to prevent autoimmune disease. B cells in the spleens of mice that harbor anti-insulin BCR transgenes (125Tg) are maintained in a functionally silenced or anergic state by endogenous hormone, but it is not clear when and where anergy is induced. An in vitro bone marrow culture system was therefore used to probe whether small protein hormones, a critical class of autoantigens, could interact with the BCR to induce anergy early during B cell development. Upon exposure to insulin, anti-insulin (125Tg) immature B cells show similar hallmarks of anergy as those observed in mature splenic B cells. These include BCR down-regulation, impaired proliferative responses to anti-CD40, and diminished calcium mobilization upon stimulation with BCR-dependent and independent stimuli. Inhibition of calcineurin also results in reduced immature B cell proliferation in a similar manner, suggesting a potential mechanism through which reduced intracellular calcium mobilization may be altering cellular proliferation. Signs of impairment appear after short-term exposure to insulin, which are reversible upon Ag withdrawal. This suggests that a high degree of functional plasticity is maintained at this stage and that constant Ag engagement is required to maintain functional inactivation. These findings indicate that tolerance observed in mature, splenic 125Tg B cells is initiated by insulin in the developing B cell compartment and thus highlight an important therapeutic window for the prevention of insulin autoimmunity.

Medición objetiva del comportamiento sedentario y la actividad física, y de sus efectos en la variabilidad de la frecuencia cardiaca, en adultos jóvenes que residen en una altitud moderada / Objective measurement of sedentary behavior and physical activity, and their effects on heart rate variability, in young adults that live in a moderate altitude

Resumen Antecedentes: El ejercicio físico y el entrenamiento de resistencia aeróbica se han asociado con un aumento de la variabilidad de la frecuencia cardiaca, mientras que el tiempo sedentario se ha asociado con una disminución de la variabilidad de la frecuencia cardiaca. Objetivo: Determinar si la variabilidad de la frecuencia cardiaca medida durante el reposo se relaciona con el tiempo sedentario y el tiempo utilizado en diferentes intensidades de actividad física, determinadas a través de un método objetivo (acelerometría), en un grupo de adultos sanos que residen a una altura de 2600 metros sobre el nivel del mar (m.s.n.m.). Método: Se realizaron mediciones de acelerometría a 99 individuos durante una semana y una medición de variabilidad de la frecuencia cardiaca en reposo. De acuerdo con la acelerometría, se realizó una división en tiempo sedentario y tiempo de actividad física de intensidad ligera, moderada y vigorosa. Para analizar la variabilidad de la frecuencia cardiaca se utilizaron parámetros en el dominio del tiempo (intervalos normales [NN], desviación estándar de los intervalos normales [SDNN], raíz cuadrada del promedio de las diferencias al cuadrado entre intervalos normales adyacentes [RMSSD]) y de la frecuencia (potencia de la baja frecuencia [LF], potencia de la alta frecuencia [HF], LF/HF) para analizar la variabilidad de la frecuencia cardiaca. Mediante de modelos de regresión se buscó la asociación entre las variables de actividad física y de variabilidad de la frecuencia cardiaca. Resultados: Se presentó una asociación negativa entre los intervalos NN, la SDNN y el tiempo sedentario, así como asociaciones positivas entre el intervalo NN y la actividad física ligera, moderada y vigorosa, al igual que entre la actividad física vigorosa y las potencias de LF y HF. Todas las asociaciones anteriores fueron significativas (p< 0.05). Conclusiones: En adultos jóvenes que residen a 2600 m.s.n.m., el tiempo sedentario reduce la variabilidad de la frecuencia cardiaca, mientras que la actividad física vigorosa aumenta dicha variabilidad.

Abstract Background: Physical exercise and aerobic resistance training have been associated with increased heart rate variability, while sedentary time has been associated with decreased heart rate variability. Objective: To determine if heart rate variability measured at rest is related to sedentary time and time used in various intensities of physical activity, established through an objective method (accelerometry), in a group of healthy adults who live 2,600 meters above sea level. Method: Accelerometer measurements were taken in 99 individuals during one week along with one measurement of heart rate variability at rest. Time was divided into sedentary time and time spent in light, moderate and vigorous physical activity. Time (NN interval, SDNN, RMSSD) and frequency (LF, HF, LF/HF) domain parameters were used to analyze heart rate variability. Using regression models, an association was sought between the physical activity and heart rate variability variables. Results: There was a negative association between NN intervals, SDNN and sedentary time, as well as positive associations between the NN interval and light, moderate and vigorous physical activity, and between vigorous physical activity and LF and HF power. All the foregoing associations were significant (p< 0.05). Conclusions: In young adults living 2,600 meters above sea level, sedentary time reduces heart rate variability, while vigorous physical activity increases this variability.

In situ redox speciation analysis of chromium in water by diffusive gradients in thin films using a DE81 anion exchange membrane.

A method for the in situ redox speciation analysis of chromium in water by the diffusive gradients in thin films (DGT) technique using a DE81 anion exchange membrane was successfully developed. For the selective uptake of Cr(VI), a DGT device containing an anion exchange membrane DE81 (cellulose acetate chromatographic paper) was used (DE81-DGT), while selective uptake of Cr(III) was carried out using DGT devices containing the Chelex-100 resin (Chelex-100-DGT). A correlation coefficient of 0.993 was obtained for the linearity of the immersion curves (mass versus time) using DE81-DGT. The diffusion coefficient values for Cr(VI) through the agarose diffusive layer were equal to 4.89±0.5×10(-6)cm(2)s(-1) and 3.95±0.02×10(-6)cm(2)s(-1) (T=23±1°C, I=0.03molL(-1) NaNO3) were obtained by using diffusion cell and immersion curves, respectively. The retention of Cr(VI) by the DE81 membrane in a synthetic sample and river water was not affected by the pH over a wide range 4-9). Recoveries of Cr(VI) between 90% and 120% from solutions of ionic strength ranging from 0.01 to 0. 5molL(-1) NaNO3 were achieved. Finally, the redox speciation analysis of Cr(III) and Cr(VI) in spiked river water and synthetic samples was performed with recoveries greater than 80% and 87% by using Chelex-100-DGT and DE81-DGT devices, respectively. Those results were in excellent agreement with the diphenylcarbazide spectrophotometric method.

Sequential injection analysis implementing multiple standard additions for As speciation by liquid chromatography and atomic fluorescence spectrometry (SIA-HPLC-AFS).

An analytical procedure for multiple standard additions of arsenic species using sequential injection analysis (SIA) is proposed for their quantification in seafood extracts. SIA presented flexibility for generating multiple specie standards at the ng mL(-1) concentration level by adding different volumes of As(III), As(V), monomethylarsonic (MMA) and dimethylarsinic (DMA) to the sample. The mixed sample plus standard solutions were delivered from SIA to fill the HPLC injection loop. Subsequently, As species were separated by HPLC and analyzed by atomic fluorescence spectrometry (AFS). The proposed system comprised two independently controlled modules, with the HPLC loop acting as the intermediary device. The analytical frequency was enhanced by combining the actions of both modules. While the added sample was flowing through the chromatographic column towards the detection system, the SIA program started performing the standard additions to another sample. The proposed method was applied to spoiled seafood extracts. Detection limits based on 3σ for As(III), As(V), MMA and DMA were 0.023, 0.39, 0.45 and 1.0 ng mL(-1), respectively.

Impaired intracellular calcium mobilization and NFATc1 availability in tolerant anti-insulin B cells.

B lymphocytes that recognize soluble self-Ags are routinely found in normal individuals in a functionally inactive or anergic state. Current models indicate that this tolerant state is maintained by interactions with self-Ags that uncouple the BCR from downstream signaling pathways and increase levels of free calcium. Contrary to this expectation, B cells that harbor anti-insulin Ig transgenes (125Tg) are maintained in a tolerant state even though free calcium levels remain normal and tyrosine kinase substrate phosphorylation is preserved following BCR stimulation. Under basal conditions, intracellular levels of inositol 1,4,5-trisphosphate are increased and NFATc1 levels are reduced in 125Tg B cells. The 125Tg B cells are markedly impaired in their ability to mobilize calcium upon stimulation with ionomycin, and BCR-induced calcium mobilization from internal stores is decreased. In contrast, poisoning intracellular calcium pumps with thapsigargin increases calcium mobilization in 125Tg B cells. Changes in calcium signaling are accompanied by a failure of 125Tg B cells to translocate NFATc1 into the nucleus following stimulation with either anti-IgM or ionomycin. Thus, disassociation of BCR from multiple signaling pathways is not essential for maintaining tolerance in anti-insulin 125Tg B cells. Rather, BCRs that are occupied by autologous insulin deliver signals that induce changes in intracellular calcium mobilization and maintain tolerance by preventing activation of key transcription factors such as NFAT.

Uncoupling of anergy from developmental arrest in anti-insulin B cells supports the development of autoimmune diabetes.

Loss of tolerance is considered to be an early event that is essential for the development of autoimmune disease. In contrast to this expectation, autoimmune (type 1) diabetes develops in NOD mice that harbor an anti-insulin Ig transgene (125Tg), even though anti-insulin B cells are tolerant. Tolerance is maintained in a similar manner in both normal C57BL/6 and autoimmune NOD mice, as evidenced by B cell anergy to stimulation through their Ag receptor (anti-IgM), TLR4 (LPS), and CD40 (anti-CD40). Unlike B cells in other models of tolerance, anergic 125Tg B cells are not arrested in development, and they enter mature subsets of follicular and marginal zone B cells. In addition, 125Tg B cells remain competent to increase CD86 expression in response to both T cell-dependent (anti-CD40) and T cell-independent (anti-IgM or LPS) signals. Thus, for anti-insulin B cells, tolerance is characterized by defective B cell proliferation uncoupled from signals that promote maturation and costimulator function. In diabetes-prone NOD mice, anti-insulin B cells in this novel state of tolerance provide the essential B cell contribution required for autoimmune beta cell destruction. These findings suggest that the degree of functional impairment, rather than an overt breach of tolerance, is a critical feature that governs B cell contribution to T cell-mediated autoimmune disease.

La sistematizaçäo del diagnóstico psiquiátrico: la sistematización de la historia clínica psiquiátrica / Systematization of psychiatric diagnosis: systematization of the psychiatric clinical history

Se presenta un informe de los métodos y resultados empleados y obtenidos en dos proyectos de grado de Ingeniería de Sistemas y de Investigación en Psiquiatría Clínica para la sistematización del diagnóstico psiquiátrico y de la historia clínica psiquiátrica. Se revisa sumariamente la bibliografía. Se elaboraron programas de computación con los sistemas AMDP System, DSM III, CIE 9 PSE/CATEGO, y BPRS para el diagnóstico psiquiátrico. Se elaboró un modelo de Historia Clínica Psiquiátrica Unificada, sistematizada tomando como guías y modelos el Sistema AMDP de habla alemana y la HCU del Grupo para el Progreso de la Psiquiatría, de Madrid, con las adaptaciones y ajustes necesarios para las necesidades y características nacionales, y de acuerdo con las normas del Ministerio de Salud. Estos programas serán muy útiles para trabajos de investigación clínicos y epidemiológicos y para la enseñanza de psiquiatría y psicopatología