Pharmacokinetics of a new fixed-dose combination of candesartan cilexetil, hydrochlorothiazide, and rosuvastatin in healthy adult subjects.

BACKGROUND: A fixed-dose combination (FDC) of candesartan cilexetil, hydrochlorothiazide and rosuvastatin (CC/HCTZ/RSV) has been developed to enhance patient compliance in the primary prevention of cardiovascular diseases. OBJECTIVE: To evaluate if the combination of the product components in the new FDC capsule formulation affects their respective pharmacokinetic and in vitro dissolution patterns. MATERIALS AND METHODS: In vitro dissolution profiles were compared in USP-43 and in biorelevant dissolution media. In vivo comparisons were obtained in a randomized, open-label, single-dose, two-treatment, two-way crossover study in 24 healthy subjects. During each treatment period, subjects received the test formulation (FDC hard capsule containing CC/HCTZ/RSV) or the reference formulation (co-administration of a FDC CC/HCTZ tablet and a RSV tablet). Plasma samples were collected periodically over 48 hours post-dose. Safety and tolerability were assessed. RESULTS: Dissolution profiles of all active drugs in the Test (capsule) and Reference Products (as tablets) were within the tolerance dissolution criteria of USP-43 conditions. HCTZ dissolution profiles were closely similar whereas those for RSV and CC did not match at specific pHs. In the pharmacokinetic study, the 90% confidence intervals (CIs) for the geometric least-square mean ratios of Cmax, AUC0-last, and AUC0-inf were 0.95 - 1.18, 0.95 - 1.15 and 0.95 - 1.13 (CC); 0.91 - 1.10, 0.96 - 1.08, and 0.96 - 1.09 (HCTZ) and 0.82 - 1.23, 0.81 - 1.13, and 0.82 - 1.12 (RSV), respectively. All adverse events were mild. CONCLUSION: The new FDC product (Sinlip Prevent), a stable FDC hard capsule, was bioequivalent (similar pharmacokinetics) when compared to the co-administration of the components and may be considered as a suitable and simplified medication for cardiovascular disease management.

Active Role of the Buffer in the Proton-Coupled Electron Transfer of Immobilized Iron Porphyrins.

Evaluation of the proton-coupled electron transfer thermodynamics of immobilized hemin is challenging due to the disparity of its electrochemical titration curves reported in the literature. Deviations from the one-electron, one-proton transfer at circumneutral pHs have been commonly ascribed to either the formation of dimeric species or the ionization of a second iron-bound water molecule. Herein, however, we report on non-idealities in the more acidic region, whose onset and extent vary with the nature and concentration of the commonly used phosphate and acetate buffers. It is shown that these deviations originate in the ligand-exchange binding between the oxidized aquo-hemin complex and the anionic components of the buffer, so that they are restricted to the pH interval where these forms coexist. A stepwise approach was developed to quantify unambiguously the apparent and intrinsic binding equilibrium constants. The apparent binding equilibrium constant exhibits a peak-shaped pH dependence, whose maximum is located at approximately the midpoint between the pKa of the iron-bound water and the first pKa of the buffer, and its magnitude is greater for the phosphate than for the acetate buffer. But strikingly, the opposite trend was found for the magnitude of the intrinsic binding equilibrium constants determined from the apparent ones, due to the different relative locations of the phosphoric and acetic pKa values with respect to that of the oxidized aquo-hemin. To probe the role of the heme propionic residues, a similar study was carried out with a propionic-free iron porphyrin containing eight ethyl residues. These substituents decrease the acidity of the iron-bound water, strengthen the iron(III)-acetate binding, weaken the iron(III)-dihydrogen phosphate binding, and enable the binding between iron(III) and monohydrogen phosphate, which was hampered in hemin by the presence of the negatively charged propionate residues. Overall, this work provides a more complete speciation of immobilized iron porphyrins under acidic conditions than previously considered, showing the substitutional lability of the aqua ligand in the oxidized state of the iron center and the reluctance of its hydroxyl counterpart to anion exchange. Knowledge of these redox- and pH-dependent bindings with the buffer components is crucial for a rigorous quantification of the proton-coupled electron transfer and the electrocatalytic activity of iron porphyrins.

Reducing Allostatic Load in Depression and Anxiety Disorders: Physical Activity and Yoga Practice as Add-On Therapies.

The allostatic load (AL) index constitutes a useful tool to objectively assess the biological aspects of chronic stress in clinical practice. AL index has been positively correlated with cumulative chronic stress (physical and psychosocial stressors) and with a high risk to develop pathological conditions (e.g., metabolic syndrome, cardiovascular pathology, inflammatory disorders) and the so-called stress-related psychiatric disorders, including anxiety and depressive disorders. Chronic stress has negative effects on brain neuroplasticity, especially on hippocampal neurogenesis and these effects may be reversed by antidepressant treatments. Several evidences indicate that non-pharmacological interventions based on physical activity and yoga practice may add synergizing benefits to classical treatments (antidepressant and benzodiazepines) for depression and anxiety, reducing the negative effects of chronic stress. The aim of this review is to provide a general overview of current knowledge on AL and chronic stress in relation to depression and anxiety, physical activity and yoga practice.

What controls the unusual melting profiles of small AuNPs/DNA complexes.

The effect of the addition of low concentrations of an inner electrolyte on ds-DNA CT-DNA (calf thymus DNA) and ss-DNA conformational changes induced by small N-(2-mercaptopropionyl)glycine gold nanoparticles (AuNPs) is here studied in detail by using different spectroscopic and structural techniques. The high affinity of ss-DNA to AuNPs compared with ds-DNA is easily demonstrated by the results of competitive binding with SYBR Green I (SG). Additionally, it is proven that at 25.0 °C, AuNPs/ds-DNA and AuNPs/ss-DNA complexes undergo a transition from extended-coil to more compact structures when the AuNPs concentration (CAuNPs) is increased, which for the ds-DNA system is accompanied by partial denaturation. Particularly, for the AuNPs/ss-DNA system all of these techniques confirm that at a high CAuNPs, the compaction process is followed by a discrete transition to aggregation and an increase in structure size. A thorough analysis of the conformational changes described indicates that these processes are larger in low salt concentration and at high temperature. However, the most striking feature of this work is the abnormal melting temperature profiles (Tm) registered at high R = CAuNPs/CDNA ratios, which are remarkable and of interest for chemical sensing. At a suitable R ratio, which varies depending on CNaCl, a complex melting profile for the AuNPs/ds-DNA system was registered with two characteristic transitions: Tm,1 = 65.0 °C and Tm,2 = 95.0 °C. The highly sensitive atomic force microscopy technique performed at 25.0 °C and 65.0 °C also showed a different behaviour in both ss- and AuNPs/ds-DNA systems, which explains the characteristic melting curves. Specifically for the AuNPs/ss-DNA system, AFM at 25.0 °C revealed the formation of large-sized aggregates formed by AuNPs/ss-DNA compact structures linked by AuNPs. However, when both AuNPs/ds-DNA and AuNPs/ss-DNA complexes were incubated at 65.0 °C, the formation of highly stable ordered structures was always visualized at high R. Therefore, this shows that some key parameters for effective control of the formation of DNA/RNA-linked particles are: the selection of an optimal temperature below the ds-DNA melting point, an appropriate CAuNPs, and the addition of low CNaCl. The optimization of these parameters for each AuNPs/DNA system could improve biological sensing and DNA/RNA delivery.

25-Hydroxyvitamin D serum levels in rheumatic female patients in southeast Spain: The paradigm of daily optimal sunshine levels and inadequate vitamin D status / Concentraciones séricas de 25-hidroxivitamina D en mujeres reumáticas del sureste de España: el paradigma de los niveles diarios óptimos de luz solar y la insuficiencia de vitamina D

Background: Almeria is a region in southeast Spain with optimal sunlight levels, along with low pluvial and pollution rates. If exposure to sunlight is sufficient to maintain adequate levels of vitamin D (25OHD), this population should display high serum levels. Objectives: To describe 25OHD serum status in women from Almeria and evaluate the impact of long sunlight exposure along the seasons on 25OHD. Methods: Cross-sectional study, performed in women consecutively recruited from an outpatient rheumatology clinic. Serum levels of 25OHD were assessed in all patients and evaluated according to age (<48 yrs, 48-53 yrs, 54-60 yrs and >60 yrs), season, and presence or absence of menopause. Clinical and laboratory variables that could affect status of vitamin D were also considered. Results: The sample included 319 Caucasian female patients. Mean 25OHD were 30.2ng/ml with 195 (61.1%) exhibiting 25OHD inadequate serum levels. Season had a significant effect on 25OHD levels, with autumn being the season in which 25OHD serum levels remained well above 30ng/ml in all age bands, and winter the season with more levels of insufficiency. Menopause did not modify 25OH serum levels. Women whose age was below 48 and over 60 had inadequate levels of 25OHD during summer. Conclusions: Optimal levels of sunlight could not overcome the problem of inadequate 25OHD serum levels, particularly in elderly and young female population. Vitamin D supplementation may be recommended predominantly in winter and summer in this population

Antecedentes: Almería es una región del sureste de España con un grado óptimo de luz solar, junto con bajas tasas de contaminación y lluvia. Si la exposición a la luz solar es suficiente para mantener niveles adecuados de vitamina D (25OHD), esta población debería presentar concentraciones séricas altas. Objetivos: Describir los valores séricos de 25OHD en mujeres de Almería y evaluar el efecto de la exposición prolongada a la luz solar sobre la 25OHD a lo largo de las distintas estaciones. Métodos: Estudio transversal en mujeres reclutadas consecutivamente en una consulta externa de reumatología. Se determinaron las concentraciones séricas de 25OHD en todas las pacientes y se valoraron en función de la edad (< 48 años, 48-53 años, 54-60 años y > 60 años), la estación y la presencia o ausencia de menopausia. También se tuvieron en cuenta las variables clínicas y analíticas que pudieran afectar al estado de la vitamina D. Resultados: La muestra incluyó 319 mujeres de raza blanca. El valor medio de 25OHD fue de 30,2 ng/ml, y 195 (61,1%) mostraron concentraciones séricas inadecuadas de 25OHD. La estación tenía un efecto importante en las concentraciones de 25OHD, y el otoño era la estación en la que los valores séricos de 25OHD se mantenían bastante por encima de 30 ng/ml en todas las franjas de edad, y el invierno la estación con más grado de insuficiencia. La menopausia no modificaba las concentraciones séricas de 25OH. Las mujeres menores de 48 años y mayores de 60 años tenían niveles insuficientes de 25OHD durante el verano. Conclusión: La luz solar óptima no podía superar el problema de la insuficiencia de las concentraciones séricas de 25OHD, sobre todo en las poblaciones de mujeres mayores y jóvenes. Pueden recomendarse suplementos de vitamina D predominantemente en invierno y en verano en esta población

25-Hydroxyvitamin D serum levels in rheumatic female patients in southeast Spain: The paradigm of daily optimal sunshine levels and inadequate vitamin D status.

BACKGROUND: Almeria is a region in southeast Spain with optimal sunlight levels, along with low pluvial and pollution rates. If exposure to sunlight is sufficient to maintain adequate levels of vitamin D (25OHD), this population should display high serum levels. OBJECTIVES: To describe 25OHD serum status in women from Almeria and evaluate the impact of long sunlight exposure along the seasons on 25OHD. METHODS: Cross-sectional study, performed in women consecutively recruited from an outpatient rheumatology clinic. Serum levels of 25OHD were assessed in all patients and evaluated according to age (<48 yrs, 48-53 yrs, 54-60 yrs and >60 yrs), season, and presence or absence of menopause. Clinical and laboratory variables that could affect status of vitamin D were also considered. RESULTS: The sample included 319 Caucasian female patients. Mean 25OHD were 30.2ng/ml with 195 (61.1%) exhibiting 25OHD inadequate serum levels. Season had a significant effect on 25OHD levels, with autumn being the season in which 25OHD serum levels remained well above 30ng/ml in all age bands, and winter the season with more levels of insufficiency. Menopause did not modify 25OH serum levels. Women whose age was below 48 and over 60 had inadequate levels of 25OHD during summer. CONCLUSIONS: Optimal levels of sunlight could not overcome the problem of inadequate 25OHD serum levels, particularly in elderly and young female population. Vitamin D supplementation may be recommended predominantly in winter and summer in this population.

Reversible DNA compaction induced by partial intercalation of 16-Ph-16 gemini surfactants: evidence of triple helix formation.

The interaction between calf thymus DNA and the gemini surfactants N,N'-[α,ω-phenylenebis(methylene)bis [N,N'-dimethyl-N-(1-hexadecyl)]-ammonium dibromide], p-16-Ph-16 (α = 1, ω = 3) and m-16-Ph-16 (α = 1, ω = 2), has been investigated via circular dichroism, fluorescence and UV-vis spectroscopy, zeta potential, dynamic light scattering, and AFM microscopy. Measurements were carried out in aqueous media at different molar ratios, R = (C16-Ph-16)/CDNA and C16-Ph-16 always below the critical micellar concentration (CMC) of the surfactant. Under these conditions, DNA undergoes two reversible conformational changes, compaction and decompaction, due to interaction with the surfactant molecules at low and high molar ratios, respectively. The extent of such conformational changes is correlated with both the degree of surfactant partial intercalation, and the size and charge of the surfactant aggregates formed, in each case. Comparison of the results shows that the para-form of the surfactant intercalates into the DNA to a major extent; therefore, the compaction/decompaction processes are more effective. Among these, the structure of the resulting 16-Ph-16/DNA decompacted complex is worthy of note. For the first time it can be demonstrated that the partial intercalation of the 16-Ph-16 gemini surfactants induces the formation of triplex DNA-like structures at a high R ratio.

Valoración bioquímica de la saliva, orina y material fecal de pacientes pediátricos con trastornos del espectro autista (TEA) / Biochemical assessment of saliva, urine and fecal samples in pediatric patients with autism spectrum disorders

En un grupo de 46 niños y adolescentes (5-14 años de edad) con trastornos del espectro autista, consumo elevado de harinas y azucares en su dieta y antecedentes de consumo de antibióticos frecuentes, se analizan muestras de saliva, orina y materia fecal (n=15). Comparados con muestras de un grupo normal (n=10), se detectan variaciones significativas en el pH salival, tiempo de recuperación del pH, viscosidad, flujo, y valores elevados de IgA e IgG en saliva. En orina predomina la proteinuria y la acidez, en la materia fecal no se hallaron parásitos ni C albicans. Estos cambios pueden responder a fenómenos alérgicos y alteraciones de la permeabilidad intestinal aspectos que deben ser investigados luego, pero los resultados muestran variantes significativas que permitirán elegir los sujetos preferentes para futuras investigaciones y/o generar la sospecha para la derivación temprana de pacientes sin diagnóstico y con síntomas mínimos (AU)

Samples of saliva, urine and fecal (n=15) was analyzed in a group of 46 children and teenagers (5-14 years old) with autism spectrum disorders, high consumption of flour and sugar with diet, and a history of frequent antibiotic consumption. Compared to a group of normal children (n=10), significant variations in saliva composition as pH, time to pH recovery, viscosity, flux and IgA and IgG concentration were observed, proteinuria and acidity findings predominate in the urinalysis, and the absence of parasites and C Albicans were notices at the fecal samples. These changes can respond to immune-allergic and intestinal permeability conditions, aspects that should be further investigated. Patients with these findings can be preferentially select for future studies and/ or generate suspects in undiagnosed individuals with minimal symptoms that can be early derive to proper treatment (AU)

Weak coordination between leaf structure and function among closely related tomato species.

Theory predicts that natural selection should favor coordination between leaf physiology, biochemistry and anatomical structure along a functional trait spectrum from fast, resource-acquisitive syndromes to slow, resource-conservative syndromes. However, the coordination hypothesis has rarely been tested at a phylogenetic scale most relevant for understanding rapid adaptation in the recent past or for the prediction of evolutionary trajectories in response to climate change. We used a common garden to examine genetically based coordination between leaf traits across 19 wild and cultivated tomato taxa. We found weak integration between leaf structure (e.g. leaf mass per area) and physiological function (photosynthetic rate, biochemical capacity and CO2 diffusion), even though all were arrayed in the predicted direction along a 'fast-slow' spectrum. This suggests considerable scope for unique trait combinations to evolve in response to new environments or in crop breeding. In particular, we found that partially independent variation in stomatal and mesophyll conductance may allow a plant to improve water-use efficiency without necessarily sacrificing maximum photosynthetic rates. Our study does not imply that functional trait spectra, such as the leaf economics spectrum, are unimportant, but that many important axes of variation within a taxonomic group may be unique and not generalizable to other taxa.

Impact of alprazolam in allostatic load and neurocognition of patients with anxiety disorders and chronic stress (GEMA): observational study protocol.

INTRODUCTION: The allostatic load model explains the additive effects of multiple biological processes that accelerate pathophysiology related to stress, particularly in the central nervous system. Stress-related mental conditions such as anxiety disorders and neuroticism (a well-known stress vulnerability factor), have been linked to disturbances of hypothalamo-pituitary-adrenal with cognitive implications. Nevertheless, there are controversial results in the literature and there is a need to determine the impact of the psychopharmacological treatment on allostatic load parameters and in cognitive functions. Gador study of Estres Modulation by Alprazolam, aims to determine the impact of medication on neurobiochemical variables related to chronic stress, metabolic syndrome, neurocognition and quality of life in patients with anxiety, allostatic load and neuroticism. METHODS/ANALYSIS: In this observational prospective phase IV study, highly sympthomatic patients with anxiety disorders (six or more points in the Hamilton-A scale), neuroticism (more than 18 points in the Neo five personality factor inventory (NEO-FFI) scale), an allostatic load (three positive clinical or biochemical items at Crimmins and Seeman criteria) will be included. Clinical variables of anxiety, neuroticism, allostatic load, neurobiochemical studies, neurocognition and quality of life will be determined prior and periodically (1, 2, 4, 8, and 12 weeks) after treatment (on demand of alprazolam from 0.75 mg/day to 3.0 mg/day). A sample of n=55/182 patients will be considered enough to detect variables higher than 25% (pretreatment vs post-treatment or significant correlations) with a 1-ß power of 0-80. t Test and/or non-parametric test, and Pearson's test for correlation analysis will be determined. ETHICS AND DISSEMINATION: This study protocol was approved by an Independent Ethics Committee of FEFyM (Foundation for Pharmacological Studies and Drugs, Buenos Aires) and by regulatory authorities of Argentina (ANMAT, Dossier # 61 409-8 of 20 April 2009), following the law of Habeas Data and psychotherapeutic drug control. TRIAL REGISTRATION NUMBER: GEMA 20811.

Improving the understanding of DNA-propanediyl-1,3-bis(dodecyldimethylammonium) dibromide interaction using thermodynamic, structural and kinetic approaches.

A kinetic, thermodynamic and structural study of the interaction of the gemini surfactant propanediyl-1,3-bis(dimethyldodecylammonium dibromide) (12-3-12.2Br) with calf thymus DNA was carried out at several ionic strengths (NaCl) in aqueous solutions. A new 12-3-12(2+)-selective membrane was prepared in order to gain insight into the factors that control the binding of 12-3-12.2Br to DNA. We used ethidium bromide (EB) as a fluorescence probe to follow the kinetics of the interaction by using the stopped-flow fluorescence technique. The results can be explained in terms of a reaction mechanism involving two consecutive reversible (fast and slow) steps. The fast step was attributed to the union/separation of the surfactant with/from the DNA polynucleotide. Changes in the kinetic constants in the forward and backward directions were discussed in terms of the Brönsted-Pitzer equation and of the increase in hydrophobic interactions of the surfactant tails as a consequence of salting-out effects, respectively. The slow step corresponds to a conformational change of the surfactant-DNA complex to a more compacted form. The equilibrium constant, calculated from the forward and reverse rate constants of these steps, agrees with the results obtained from potentiometric titration using a 12-3-12-(2+) selective electrode.

Leaf responses to drought stress in Mediterranean accessions of Solanum lycopersicum: anatomical adaptations in relation to gas exchange parameters.

In a previous study, important acclimation to water stress was observed in the Ramellet tomato cultivar (TR) from the Balearic Islands, related to an increase in the water-use efficiency through modifications in both stomatal (g(s)) and mesophyll conductances (g(m)). In the present work, the comparison of physiological and morphological traits between TR accessions grown with and without water stress confirmed that variability in the photosynthetic capacity was mostly explained by differences in the diffusion of CO2 through stomata and leaf mesophyll. Maximization of gm under both treatments was mainly achieved through adjustments in the mesophyll thickness and porosity and the surface area of chloroplasts exposed to intercellular airspace (S(c)). In addition, the lower g(m) /S(c) ratio for a given porosity in drought-acclimated plants suggests that the decrease in gm was due to an increased cell wall thickness. Stomatal conductance was also affected by drought-associated changes in the morphological properties of stomata, in an accession and treatment-dependent manner. The results confirm the presence of advantageous physiological traits in the response to drought stress in Mediterranean accessions of tomato, and relate them to particular changes in the leaf anatomical properties, suggesting specific adaptive processes operating at the leaf anatomical level.