CONSTANS-FKBP12 interaction contributes to modulation of photoperiodic flowering in Arabidopsis.

Flowering time is a key process in plant development. Photoperiodic signals play a crucial role in the floral transition in Arabidopsis thaliana, and the protein CONSTANS (CO) has a central regulatory function that is tightly regulated at the transcriptional and post-translational levels. The stability of CO protein depends on a light-driven proteasome process that optimizes its accumulation in the evening to promote the production of the florigen FLOWERING LOCUS T (FT) and induce seasonal flowering. To further investigate the post-translational regulation of CO protein we have dissected its interactome network employing in vivo and in vitro assays and molecular genetics approaches. The immunophilin FKBP12 has been identified in Arabidopsis as a CO interactor that regulates its accumulation and activity. FKBP12 and CO interact through the CCT domain, affecting the stability and function of CO. fkbp12 insertion mutants show a delay in flowering time, while FKBP12 overexpression accelerates flowering, and these phenotypes can be directly related to a change in accumulation of FT protein. The interaction is conserved between the Chlamydomonas algal orthologs CrCO-CrFKBP12, revealing an ancient regulatory step in photoperiod regulation of plant development.

Manejo del síndrome de abstinencia alcohólica en los pacientes críticos / Management of the syndrome of alcohol withdrawal in critical patients

El manejo del síndrome de abstinencia alcohólica es un desafío en los pacientes críticos. Con frecuencia, se desconocen los antecedentes de consumo de alcohol o este dato es incompleto, lo que limita la identificación de quienes pueden desarrollar este síndrome. El cese abrupto del consumo de alcohol coloca a estos pacientes en alto riesgo de sufrir síndrome de abstinencia alcohólica grave. Típicamente, las benzodiacepinas son consideradas las drogas de primera línea para el manejo de estos casos. Sin embargo, si el paciente progresa a un estado más grave con convulsiones o delirium tremens, puede ser necesario administrar medicación adyuvante a las benzodiacepinas, como el propofol o la dexmedetomidina, o emplear estas últimas drogas como terapias alternativas en aquellos que no responden a las benzodiacepinas. La aparición de convulsiones representa un fuerte factor de riesgo para la progresión a un síndrome de abstinencia alcohólica grave, con el desarrollo posterior de delirium tremens hasta en el 30% de los casos. El delirium tremens es el cuadro más grave y ocurre en el 5-20% de los pacientes con este síndrome, con una mortalidad hasta del 25% sin tratamiento y que se reduce al 0-1% con tratamiento. Es importante conocer el antecedente del consumo de alcohol para evitar el síndrome de abstinencia alcohólica o tratar rápidamente sus síntomas más graves, y mejorar la supervivencia de estos pacientes.(AU)

Alcohol withdrawal syndrome (AWS) is a well-known and a challenging condition occurring in critically ill patients. Frequently, history of alcohol abuse is unknown when the patient is admitted to the intensive care unit, limiting the identification of those who could develop AWS. The abrupt cessation of a heavy or constant drinking put these patients in high risk of suffering from this syndrome in its severe form. Typically, benzodiazepines are considered the first line of treatment. However, if clinical conditions progress to epileptic seizures or delirium tremens or are refractory to benzodiazepines, adjuvant drugs like propofol or dexmedetomidine might be an option to control the severe symptoms. Delirium tremens can occur in up to 30% of patients; it is the most severe picture with a mortality of 25% without treatment and that can be reduced to almost 0-1% with treatment. It is important to appropriately identify alcohol abuse in order to avoid the early clinical manifestations of AWS or rapidly treat its most severe symptoms and improve survival.(AU)

Photoperiodic control of sugar release during the floral transition: What is the role of sugars in the florigenic signal?

Florigen is a mobile signal released by the leaves that reaching the shoot apical meristem (SAM), changes its developmental program from vegetative to reproductive. The protein FLOWERING LOCUS T (FT) constitutes an important element of the florigen, but other components such as sugars, have been also proposed to be part of this signal. (1-5) We have studied the accumulation and composition of starch during the floral transition in Arabidopsis thaliana in order to understand the role of carbon mobilization in this process. In A. thaliana and Antirrhinum majus the gene coding for the Granule-Bound Starch Synthase (GBSS) is regulated by the circadian clock (6,7) while in the green alga Chlamydomonas reinhardtii the homolog gene CrGBSS is controlled by photoperiod and circadian signals. (8,9) In a recent paper(10) we described the role of the central photoperiodic factor CONSTANS (CO) in the regulation of GBSS expression in Arabidopsis. This regulation is in the basis of the change in the balance between starch and free sugars observed during the floral transition. We propose that this regulation may contribute to the florigenic signal and to the increase in sugar transport required during the flowering process.

Deciphering the Role of POLYCOMB REPRESSIVE COMPLEX1 Variants in Regulating the Acquisition of Flowering Competence in Arabidopsis.

Polycomb group (PcG) proteins play important roles in regulating developmental phase transitions in plants; however, little is known about the role of the PcG machinery in regulating the transition from juvenile to adult phase. Here, we show that Arabidopsis (Arabidopsis thaliana) B lymphoma Moloney murine leukemia virus insertion region1 homolog (BMI1) POLYCOMB REPRESSIVE COMPLEX1 (PRC1) components participate in the repression of microRNA156 (miR156). Loss of AtBMI1 function leads to the up-regulation of the primary transcript of MIR156A and MIR156C at the time the levels of miR156 should decline, resulting in an extended juvenile phase and delayed flowering. Conversely, the PRC1 component EMBRYONIC FLOWER (EMF1) participates in the regulation of SQUAMOSA PROMOTER-BINDING PROTEIN-LIKE and MIR172 genes. Accordingly, plants impaired in EMF1 function displayed misexpression of these genes early in development, which contributes to a CONSTANS-independent up-regulation of FLOWERING LOCUS T (FT) leading to the earliest flowering phenotype described in Arabidopsis. Our findings show how the different regulatory roles of two functional PRC1 variants coordinate the acquisition of flowering competence and help to reach the threshold of FT necessary to flower. Furthermore, we show how two central regulatory mechanisms, such as PcG and microRNA, assemble to achieve a developmental outcome.

Nanopatterned graphene on a polymer substrate by a direct peel-off technique.

A graphene (Gr) on a polyimide (PI) polymer film (Gr-PI film), obtained by a direct peel-off technique, is proposed and investigated. Thanks to its high transparency, electrical conductivity, mechanical strength, and chemical durability, the Gr-PI film is an ideal substrate for flexible electronic and optoelectronic devices, including transistors, light-emitting diodes, and plasmonic antennas. It is obtained using a straightforward method. After spin coating and curing a PI film on Gr previously grown on Cu, one can separate the Gr-PI film from the Cu foil thanks to the difference in the adhesive energy between the Gr-Cu and Gr-PI interfaces. The resulting Gr-PI film shows an average electrical sheet resistance ranging from 520 to 860 Ω/sq and a very high optical transmission (>90%), which have allowed the demonstration of a transparent heater. The surface morphology of the Gr-PI film follows that of the Cu foil, with the latter maintaining its surface properties and allowing in this way its reuse in subsequent chemical vapor deposition growth. The method can also be applied to patterned Gr, as is demonstrated for nanosize ribbons with a width of a few tens of nanometers.

Photoperiodic control of carbon distribution during the floral transition in Arabidopsis.

Flowering is a crucial process that demands substantial resources. Carbon metabolism must be coordinated with development through a control mechanism that optimizes fitness for any physiological need and growth stage of the plant. However, how sugar allocation is controlled during the floral transition is unknown. Recently, the role of a CONSTANS (CO) ortholog (Cr-CO) in the control of the photoperiod response in the green alga Chlamydomonas reinhardtii and its influence on starch metabolism was demonstrated. In this work, we show that transitory starch accumulation and glycan composition during the floral transition in Arabidopsis thaliana are regulated by photoperiod. Employing a multidisciplinary approach, we demonstrate a role for CO in regulating the level and timing of expression of the GRANULE BOUND STARCH SYNTHASE (GBSS) gene. Furthermore, we provide a detailed characterization of a GBSS mutant involved in transitory starch synthesis and analyze its flowering time phenotype in relation to its altered capacity to synthesize amylose and to modify the plant free sugar content. Photoperiod modification of starch homeostasis by CO may be crucial for increasing the sugar mobilization demanded by the floral transition. This finding contributes to our understanding of the flowering process.

Femto to millisecond observations of indole-based squaraine molecules photodynamics in solution.

We present femto-to-millisecond studies of the photodynamics of seven types of indole-based squaraine molecules (SQs) in solvents of different H-bonding ability and viscosity. These SQs can be classified into two families: SQs with two carboxylic groups in the side indole groups (symmetrical SQs) and with only one carboxylic group (asymmetrical SQs). Steady-state absorption and fluorescence techniques show narrow absorption and emission bands, with a small Stokes shift (about 300 cm(-1)). The femtosecond transient absorption spectra give a very short (∼100 fs) dynamics (assigned to IVR) and the associated spectra show two excited species assigned to two stereoisomers. A trans-cis photoisomerization occurs in a very fast time through a conical intersection. Pico-to-nanosecond emission experiments also reveal the presence of two fluorescing trans stereoisomers whose lifetimes show similar sensitivities to the nature of solvent. For example, lifetimes of 1.72, 0.46 and 0.29 ns were determined for the trans photoisomer of the SQ 41 in triacetin, dichloromethane and acetonitrile, respectively, reflecting the short decay of the S(1) state in highly polar and low viscous solvents. Flash photolysis experiments gave the transient absorption signals of the cis photoisomer that is formed after the twisting process at S(1). The cis-to-trans photoisomerization at the ground state happens in the µs time scale (1-4 µs), and it depends on the H-bonding ability and viscosity of the solvent. Thus, combining fs-ns and ns-µs experiments suggests that in the conical intersection region, only a small fraction of the twisted trans isomers are converted to the cis ones in the excited states. These results bring detailed and global insight into the large time window photodynamics of this family of SQs in solution.

Reaction and reorganization free energies of electron-transfer reactions under restricted geometry conditions.

Electron-transfer reactions between iron and cobalt complexes were studied in beta-cyclodextrin (betaCD), 2-hydroxypropyl-beta-cyclodextrin (HbetaCD), and 18-crown-6 ether (18C6) solutions. The results were rationalized taking as the basis the Marcus-Hush formalism. We employed two different approaches, depending on the kind of receptor and solvent, to obtain the reorganization and reaction free energies that determine the reaction rate constant. The opposite trends in reactivity observed in betaCD and HbetaCD solutions and the behavior in solutions of 18C6 are explained.

Características neuropsicológicas del niño preescolar con hipotiroidismo congénito en la Provincia de Cienfuegos / Neuropsychological characteristic of preschooler children’s with congenital hypothyroidism in Provincia de Cienfuegos

El hipotiroidismo congénito es la causa más frecuente de retraso mental previsible. El diagnóstico clínico en las primeras etapas de la vida es muy impreciso, de ahí que se hayan puesto en marcha programas de diagnóstico y tratamiento precoz cuyo objetivo fundamental es un desarrollo neurocognitivo y su nivel optimización. Método y objetivos: Con el objetivo de evaluar el perfil neurocognitivo en niños hipotiroideos en edad preescolar se realizó un estudio descriptivo prospectivo que incluyó a los pacientes en edades entre 4 a 6 años con seguimiento en consulta de hipotiroidismo congénito del Hospital Pediátrico “Paquito González Cueto” de Cienfuegos. Solo existían 6 niños a los cuales se les aplicó la batería neuropsicológica Luria Inicial, rendimiento intelectual, escala de comportamiento y potenciales evocados. Resultados: Se constató que estos pacientes presentan limitaciones en el sistema óptico- espacial y en el sistema de control inhibitorio. El primero afecta el desarrollo de la orientación espacial del acto motor y la percepción visual con detalles y el otro sistema afecta el control atencional en la edad y conlleva a dificultades para seguir instrucciones verbales. Recomendación: El seguimiento y la vigilancia del neurodesarrollo permiten ir explicando las alteraciones sistemáticas que se presentan en estos niños y hace posible una intervención temprana a favor del posterior proceso de escolarización.

The congenital hipotiroidismo is the most frequent cause of foreseeable mental delay. The clinical diagnosis in the first stages of the life is very vague, for that reason diagnostic programs and precocious treatment have started up whose main target is a neurocognitivo development and its level optimization. Method and objectives: With the aim of evaluating the neurocognitivo profile in hypothyroid children in pre-school age a prospective descriptive study was realised that it included to the patients in ages between 4 to 6 years with pursuit in consultation of congenital hipotiroidismo of the Paediatric Hospital “Paquito González Fortified height” of Cienfuegos. 6 children only existed to who he was applied the neuropsicológica battery Initial Luria, intellectual yield, evoked scale of behavior and potentials to them. Results: It was stated that these patients present/display limitations in the space optical system and in the inhibiting control system. First it affects the development of the spatial orientation of the motor act and the visual perception with details and the other system affects the attention control in the age and entails to difficulties to follow instructions verbal. Recommendation: The pursuit and the monitoring of neurodesarrollo allow to be explaining the systematic alterations that appear in these children and makes an early intervention in favor of the later process possible of schooling.

Controlled deposition of silver nanoparticles in mesoporous single- or multilayer thin films: from tuned pore filling to selective spatial location of nanometric objects.

Silver nanoparticle assemblies are embedded within mesoporous oxide thin films by an in situ mild reduction leading to nanoparticle-mesoporous oxide thin-film composites (NP@MOTF). A quantitative method based on X-ray reflectivity is developed and validated with energy dispersive spectroscopy in order to assess pore filling. The use of dilute formaldehyde solutions leads to control over the formation of silver nanoparticles within mesoporous titania films. Inclusion of silver nanoparticles in mesoporous silica requires more drastic conditions. This difference in reactivity can be exploited to selectively synthesize nanoparticles in a predetermined layer of a multilayered mesoporous stack leading to complex 1D-ordered multilayers with precise spatial location of nanometric objects. The metal oxide nanocomposites synthesized have potential applications in catalysis, optical devices, surface-enhanced Raman scattering, and metal enhancement fluorescence.

[Disseminated candidiasis in parenteral drug addicts. Report of 15 cases]. / Candidiasis diseminada en adictos a drogas por vía parenteral. Presentación de 15 casos.

Fungic infections related to parenteral use of drugs increased significantly from 1980 on with the description of the disseminated candidiasis syndrome. Associated to the administration of brown heroin, this syndrome is characterized by the development of cutaneous, ocular and osteoarticular infections, isolated or combined, by Candidas albicans. We present 15 patients with disseminated candidiasis: 12 developed ocular affection (10 endophthalmitis and 2 chorioretinitis): 9, cutaneous lesions and 3 osteoarticular affection (3 costochondritis and one hip arthritis); 8 presented simultaneous infections in several locations. The biopsy and culture of the cutaneous lesions was the most profitable test in order to establish the microbiological diagnosis. We comment on the main etiopathogenetic, clinical, diagnostic and therapeutic aspects of the disseminated candidiasis syndrome.

[Beta-thromboglobulin levels and atherosclerosis. Its relationship with the presence of risk factors]. / Niveles de beta-tromboglobulina y aterosclerosis. Su relación con la presencia de factores de riesgo.

In order to evaluate whether plasma beta-thromboglobulin (as a marker of the degree of platelet function) in patients presenting clinically evident atherosclerosis is related to the presence or absence of different risk factors (smoking habit, arterial hypertension, hypercholesterolemia, diabetes, hypertriglyceridemia, obesity, hyperuricemia, alcoholism), 40 patients have been studied in whom mean beta-thromboglobulin levels was 54 +/- 25.56 ng/ml, which is very superior to levels considered normal. However, the presence of one or more risk factors did not lead to significant variations in b-thromboglobulin concentrations, and no differences were found either when each risk factor was considered separately. The positive correlation (r = 0.98; p less than 0.01) between beta-thromboglobulin and apo B levels is highlighted. The results suggest that platelet hyperfunction seems to be due to a greater extent to the atherosclerotic process rather than to the existence of a particular risk factor.

Lesion renal en lupus sistemico con enfasis en el sindrome nefrotico. / Renal lesions in systemic lupus with enphasis in nephrotic syndrome

Se estudian 5 ninos con lupus sistemico senalandose sus caracteristicas clinicas, patologicas y evolutivas, enfatizando sus hallasgos renales. Lupus eritematoso sistemico; Nefrosis; Colagenosis

Lesion renal en la sifilis congenita. / Renal injury in congenital syphilis

Se estudiaron los hallazgos histopatologicos renales de 19 ninos diagnosticados de sifilis congenitas que fallecieron. En nueve (47%) de los casos se encontraron alteraciones; cinco glomerulares y cuatro tubulares. Los cambios glomerulares consistieron en engrosamiento de la membrana basal (3), hialinizazion (1) y fibrosis(1). Los hallazgos tubulares consistieron en cambios degenerativos en tres y vasculares en uno. El sindrome nefrotico se asocio a alteraciones membranosas y a glomerulos hialinizados. Los hallazgos urinarios fueron minimos