Chiral nanotubes self-assembled from discrete non-covalent macrocycles.

Many strategies have been used to construct supramolecular hollow tubes, including helical folding of oligomers, bundling of rod-like structures, rolling-up of sheets and stacking of covalent cycles. On the other hand, controlling chirality at the supramolecular level continues attracting much interest because of its implications in future applications of porous systems. This review article covers the main examples in the literature that use simple molecular structures as chiral units for precise assembly into discrete non-covalent cyclic structures that are able to form chiral supramolecular tubular systems.

Guidelines for the assembly of hydrogen-bonded macrocycles.

The formation of well-defined, discrete self-assembled architectures relies on the interplay between non-covalent interactions and cooperative phenomena. In particular, chelate or intramolecular cooperativity is responsible for the assembly of closed, cyclic structures in competition with open, linear oligomers, and it can be enhanced in several ways to increase the stability of a given cycle size. In this article, we review the work of several researchers on the synthesis of hydrogen-bonded macrocycles from ditopic molecules and analyze the main factors, often interrelated, that influence the equilibrium between ring and chain species. Emphasis will be set on the diverse features that can increase cyclization fidelity, including monomer geometry, template effects, conformational effects, intramolecular interactions and H-bonding pattern.

A pyrene-functionalized foldamer: structural impact and recognition properties supported by donor-acceptor interactions.

An electroactive and luminescent foldamer based on an oligopyridine biscarboxamide skeleton was synthesized and characterised. Its conformation in the solid state proved to be strongly affected by the peripheral pyrene units. The latter also endow the target derivative with recognition abilities toward electron-withdrawing molecules, which allow tuning of the spectroscopic properties of the foldamer.

Anthropogenic versus mineral aerosols in the stimulation of microbial planktonic communities in coastal waters of the northwestern Mediterranean Sea.

The atmosphere of the northwestern (NW) Mediterranean Sea is affected by continuous inputs of anthropogenic aerosols and episodic Saharan dust events. These atmospheric inputs deliver to the surface waters high amounts of macronutrients and trace metals that can constitute their main source at certain times of the year. The effect of both anthropogenic and crustal particles over the autotrophic and heterotrophic planktonic community assembles was evaluated through three microcosm experiments carried out in the summer of 2013 and in the winter and spring of 2014 at an urban coastal location of the NW Mediterranean (Barcelona, Spain). Particles were added to seawater at a concentration of 0.8mgl-1. The results showed that (i) a greater stimulation of the whole community was observed in summer and spring than in winter; (ii) both kinds of aerosols produced an increase in the growth of phytoplankton, although the stimulation of nanoeukaryotes was significantly larger with anthropogenic aerosols; and (iii) bacterial abundance increased more with mineral dust, whereas bacterial production was more stimulated with anthropogenic inputs. Overall, the effect of atmospheric particles was dependent on their composition and solubility in seawater, as well as on the initial biogeochemical conditions present in the seawater and had the potential to change the net metabolic balance of the microbial planktonic community.

Human resident CD34+ stromal cells/telocytes have progenitor capacity and are a source of αSMA+ cells during repair.

We studied the progenitor capacity of human resident CD34+ stromal cells/telocytes (SC/TCs) in the enteric wall affected by inflammatory/repair processes (appendicitis, diverticulitis of large bowel and Crohn's disease of the terminal ileum) at different stages of evolution (inflammatory, proliferative and remodelling). In these conditions, CD34+ SC/TCs are activated, showing changes, which include the following overlapping events: 1) separation from adjacent structures (e.g., from vascular walls) and location in oedematous spaces, 2) morphological modifications (in cell shape and size) with presence of transitional cell forms between quiescent and activated CD34+ SC/TCs, 3) rapid proliferation and 4) loss of CD34 expression and gain of αSMA expression. These events mainly occur in the inflammatory and proliferative stages. During the loss of CD34 expression, the following findings are observed: a) irregular cell labelling intensity for anti-CD34, b) co-localization of CD34 and actin, c) concurrent irregular labelling intensity for αSMA and d) αSMA expression in all stromal cells, with total loss of CD34 expression. While CD34 expression was conserved, a high proliferative capacity (Ki-67 expression) was observed and vice versa. In the segments of the ileum affected by Crohn's disease, the stromal cells around fissures were αSMA+ and, in the transitional zones with normal enteric wall, activated CD34+ SC/TCs were observed. In conclusion, human resident CD34+ SC/TCs in the enteric wall have progenitor capacity and are activated with or without differentiation into αSMA+ stromal cells during inflammatory/repair processes.

BioAnnote: a software platform for annotating biomedical documents with application in medical learning environments.

Automatic term annotation from biomedical documents and external information linking are becoming a necessary prerequisite in modern computer-aided medical learning systems. In this context, this paper presents BioAnnote, a flexible and extensible open-source platform for automatically annotating biomedical resources. Apart from other valuable features, the software platform includes (i) a rich client enabling users to annotate multiple documents in a user friendly environment, (ii) an extensible and embeddable annotation meta-server allowing for the annotation of documents with local or remote vocabularies and (iii) a simple client/server protocol which facilitates the use of our meta-server from any other third-party application. In addition, BioAnnote implements a powerful scripting engine able to perform advanced batch annotations.

Ilarviruses of Prunus spp.: a continued concern for fruit trees.

Prunus spp. are affected by a large number of viruses, causing significant economic losses through either direct or indirect damage, which results in reduced yield and fruit quality. Among these viruses, members of the genus Ilarvirus (isometric labile ringspot viruses) occupy a significant position due to their distribution worldwide. Although symptoms caused by these types of viruses were reported early in the last century, their molecular characterization was not achieved until the 1990s, much later than for other agronomically relevant viruses. This was mainly due to the characteristic liability of virus particles in tissue extracts. In addition, ilarviruses, together with Alfalfa mosaic virus, are unique among plant viruses in that they require a few molecules of the coat protein in the inoculum in order to be infectious, a phenomenon known as genome activation. Another factor that has made the study of this group of viruses difficult is that infectious clones have been obtained only for the type member of the genus, Tobacco streak virus. Four ilarviruses, Prunus necrotic ringspot virus, Prune dwarf virus, Apple mosaic virus, and American plum line pattern virus, are pathogens of the main cultivated fruit trees. As stated in the 9th Report of the International Committee on Taxonomy of Viruses, virions of this genus are "unpromising subjects for the raising of good antisera." With the advent of molecular approaches for their detection and characterization, it has been possible to get a more precise view of their prevalence and genome organization. This review updates our knowledge on the incidence, genome organization and expression, genetic diversity, modes of transmission, and diagnosis, as well as control of this peculiar group of viruses affecting fruit trees.

Multiplex polymerase chain reaction (PCR) and real-time multiplex PCR for the simultaneous detection of plant viruses.

Multiplex Polymerase Chain Reaction (PCR) can be used for the simultaneous detection of plant viruses. Multiple primer pairs or polyvalent primer pairs can be used to detect and identify several viruses in a single PCR.

La baja visión. La psicología aplicada a la oftalmología / Low vision. Phsychology applied for ophthalmology

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Density functional theory fragment descriptors to quantify the reactivity of a molecular family: application to amino acids.

By using the exact density functional theory, one demonstrates that the value of the local electronic softness of a molecular fragment is directly related to the polarization charge (Coulomb hole) induced by a test electron removed (or added) from (at) the fragment. Our finding generalizes to a chemical group a formal relation between these molecular descriptors recently obtained for an atom in a molecule using an approximate atomistic model [P. Senet and M. Yang, J. Chem. Sci. 117, 411 (2005)]. In addition, a practical ab initio computational scheme of the Coulomb hole and related local descriptors of reactivity of a molecular family having in common a similar fragment is presented. As a blind test, the method is applied to the lateral chains of the 20 isolated amino acids. One demonstrates that the local softness of the lateral chain is a quantitative measure of the similarity of the amino acids. It predicts the separation of amino acids in different biochemical groups (aliphatic, basic, acidic, sulfur contained, and aromatic). The present approach may find applications in quantitative structure activity relationship methodology.

[Experimental study on usefulness of silicone-fluorsilicone copolymer oil (SiFO) in vitreoretinal surgery]. / Estudio experimental sobre la utilidad del aceite de copolímero de silicona-fluorsilicona (SiFO) en la cirugía vitreorretiniana.

PURPOSE: To evaluate the usefulness of silicone-fluorsilicone copolymer oil (SiFO) as an intraoperative tool and a vitreous substitute in vitreoretinal surgery. METHODS: Handling properties of SiFO were tested and compared with those of perfluorooctane (PFO). The transparency of both substances was measured by spectrophotometry and subjectively assessed. Their tendency to dispersion was observed during injection in balanced saline solution (BSS) and after mechanized and manual shaking. Ease of injection and aspiration through small-gauge instruments was evaluated. Ocular tolerance to SiFO and PFO was studied after intravitreal injection in rabbit eyes: intraocular pressure, anterior segment inflammatory response and dispersion were evaluated, and a histopathological study was performed. RESULTS: Injection and aspiration of SiFO were more difficult than those of PFO because of its higher viscosity. PFO dispersed progressively into small droplets as early as two days after intravitreal injection, whereas SiFO remained as a single bubble for 14 days. Histopathologically both substances induced an inflammatory response over the inferior retina, with microvacuolated macrophages and foreign body giant cells, which were larger in eyes wearing SiFO. CONCLUSIONS: SiFO may be useful as an intraoperative tool, although its main drawback is a more difficult injection and aspiration compared to PFO. It has been well tolerated as a short-term vitreous substitute, but further clinical studies are needed.

A case of self-inflicted wounding by the introduction of needles through the abdominal wall to induce abortion.

The self-inflicted wounding of a 23-year-old woman who introduced needles through the abdominal wall to induce abortion is reported. The woman first came to hospital with metrorrhagia and pain in the right iliac fossa. Initially she refused treatment and went home. Twenty-two hours later she was admitted to hospital after giving birth at home to a male fetus of 610 g. The placenta was expelled in the hospital and a sewing needle was found. Lateral and anteroposterior radiographs revealed 15 such needles in the hypogastric region, most of them at subcutaneous level. The newborn was admitted to the intensive care unit in a generally poor condition, with hypothermia, cyanosis and bradycardia. An X-ray showed a metallic object in the abdominal region which, again, corresponded to a sewing needle. The newborn did not respond to treatment and died 2h after admission.

Rehabilitación en lesiones deportivas. Bases neurofisiológicas / Rehabilitation in athletic injuries. Neurophysiological bases

El incremento de la actividad deportiva en nuestro tiempo, y por ende las patologías derivadas de dicha práctica, han creado la necesidad de la investigación del comportamiento neuromotor del organismo y las bases del entrenamiento a efectos de lograr una mejor comprensión y prevención de dichas patologías. Se analiza el proceso de maduración a partir del nacimiento, cuando el recién nacido recibe la brusca carga de la gravedad; inicia la creación de vías de información centrípeta, ésta, posteriormente se va a convertir en la vía que lleva la información mecánica en forma de sensación, e informa a las vías motoras a través de reflejos medulares, bulboprotuberanciales o corticales con participación de la conciencia, dependiendo todos estos niveles del grado de entrenamiento; información que en definitiva se conoce con el nombre de propiocepción. Tipo de sensibilidad especial que informa con dos caracteres la posición articular y el movimiento, en un sentido dinámico y entrenable. La respuesta motora de acción depende en gran medida de esta información de acuerdo a la demanda de la gravedad o del acto motor requerido. Las lesiones del deporte ocurren cuando se suceden la demanda biomecánica sin la correspondiente respuesta neurofisiológica; a la cual los tejidos sin dicha protección no pueden resistir y se injurian. En la sucesión de la patología ocurre la desaferentización, verdadera patología neurológica que es necesario corregir previamente al reintegro del deportista a su actividad (AU)

Recognition of cis-acting sequences in RNA 3 of Prunus necrotic ringspot virus by the replicase of Alfalfa mosaic virus.

Alfalfa mosaic virus (AMV) and Prunus necrotic ringspot virus (PNRSV) belong to the genera ALFAMOVIRUS: and ILARVIRUS:, respectively, of the family BROMOVIRIDAE: Initiation of infection by AMV and PNRSV requires binding of a few molecules of coat protein (CP) to the 3' termini of the inoculum RNAs and the CPs of the two viruses are interchangeable in this early step of the replication cycle. CIS:-acting sequences in PNRSV RNA 3 that are recognized by the AMV replicase were studied in in vitro replicase assays and by inoculation of AMV-PNRSV RNA 3 chimeras to tobacco plants and protoplasts transformed with the AMV replicase genes (P12 plants). The results showed that the AMV replicase recognized the promoter for minus-strand RNA synthesis in PNRSV RNA 3 but not the promoter for plus-strand RNA synthesis. A chimeric RNA with PNRSV movement protein and CP genes accumulated in tobacco, which is a non-host for PNRSV.

Importancia de la COX-2 en la regulación de la función hemodinámica y excretora renal

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Simultaneous detection of the three ilarviruses affecting stone fruit trees by nonisotopic molecular hybridization and multiplex reverse-transcription polymerase chain reaction.

ABSTRACT The three most economically damaging ilarviruses affecting stone fruit trees on a worldwide scale are the related Prunus necrotic ringspot virus (PNRSV), Prune dwarf virus (PDV), and Apple mosaic virus (ApMV). Nonisotopic molecular hybridization and multiplex reverse-transcription polymerase chain reaction (RT-PCR) methodologies were developed that could detect all these viruses simultaneously. The latter technique was advantageous because it was discriminatory. For RT-PCR, a degenerate antisense primer was designed which was used in conjunction with three virus-specific sense primers. The amplification efficiencies for the detection of the three viruses in the multiplex RT-PCR reaction were identical to those obtained in the single RT-PCR reactions for individual viruses. This cocktail of primers was able to amplify sequences from all of the PNRSV, ApMV, and PDV isolates tested in five Prunus spp. hosts (almond, apricot, cherry, peach, and plum) occurring naturally in single or multiple infections. For ApMV isolates, differences in the electrophoretic mobilities of the PCR products were observed. The nucleotide sequence of the amplified products of two representative ApMV isolates was determined, and comparative analysis revealed the existence of a 28-nucleotide deletion in the sequence of isolates showing the faster electrophoretic mobility. To our knowledge, this is the first report on the simultaneous detection of three plant viruses by multiplex RT-PCR in woody hosts. This multiplex RT-PCR could be a useful time and cost saving method for indexing these three ilarviruses, which damage stone fruit tree yields, and for the analysis of mother plants in certification programs.

Developmental toxicity in rat fetuses exposed to the benzimidazole netobimin.

Netobimin (NTB) is a prodrug of albendazole (ABZ) and is used as a broad-spectrum anthelmintic both in human and veterinary medicine. Pregnant Sprague-Dawley rats were treated po with 50, 59.5 and 70.7 mg/kg of NTB on Gestational Day (GD) 10. The results, observed on GD 20, demonstrated that NTB induced a significant increase of resorptions. Moreover, decreased fetal body weight and an increase in skeletal malformations were observed in treated groups. We report the first study in which vascular malformations are described in rats after the administration of a benzimidazole compound. An interesting relationship between intercostal vessel and rib malformations was found.

Molecular Variability Among Isolates of Prunus Necrotic Ringspot Virus from Different Prunus spp.

ABSTRACT Viral sequences amplified by polymerase chain reaction from 25 isolates of Prunus necrotic ringspot virus (PNRSV), varying in the symptomatology they cause in six different Prunus spp., were analyzed for restriction fragment polymorphisms. Most of the isolates could be discriminated by using a combination of three different restriction enzymes. The nucleotide sequences of the RNA 4 of 15 of these isolates were determined. Sequence comparisons and phylogenetic analyses of the RNA 4 and coat proteins (CPs) revealed that all of the isolates clustered into three different groups, represented by three previously sequenced PNRSV isolates: PV32, PE5, and PV96. The PE5-type group was characterized by a 5' untranslated region that was clearly different from that of the other two groups. The PV32-type group was characterized by an extra hexanucleotide consisting of a duplication of the six immediately preceding nucleotides. Although most of the variability was observed in the first third of the CP, the amino acid residues in this region, which were previously thought to be functionally important in the replication cycle of the virus, were strictly conserved. No clear correlation with the type of symptom or host specificity could be observed. The validity of this grouping was confirmed when other isolates recently characterized by other authors were included in these analyses.

Biological Properties of Apple Scar Skin Viroid: Isolates, Host Range, Different Sensitivity of Apple Cultivars, Elimination, and Natural Transmission.

Studies conducted over the last 10 years have revealed that the disease caused by the apple scar skin viroid (ASSVd) is extremely rare in Europe. ASSVd was detected by molecular hybridization and indexing in field plots on the apple indicators Starkrimson and Indo, which showed symptoms of dapple apple disease within 2 years, and rough scarred skin within 3 years, respectively. Results from both approaches were in agreement. In an attempt to improve the biological detection of ASSVd, the Japanese PK13 isolate was inoculated to 4 Prunus, 13 Malus, 17 Pyrus, and 17 other pomaceous species. All the species tested of the Malus, Pyrus, Sorbus, Chaenomeles, Cydonia, and Pyronia genera were susceptible to ASSVd based upon back indexing and hybridization, but none developed leaf or bark symptoms during a 2-year period. The viroid was not detected in the tested members of genera Amelanchier, Aronia, Cotoneaster, Crataegus, Prunus, and Pyracantha. Symptoms on fruit of 42 commercial apple cultivars experimentally inoculated with ASSVd fell into five groups ranging from inconspicuous spots to severely scarred skin and cracking. ASSVd was eliminated from most of the infected apple plants when they were subjected to a dormant stage followed by thermotherapy and shoot tip grafting. Analysis of more than 400 apple seedlings, originated from Starkrimson and Indo fruits with typical ASSVd symptoms, showed that there is little or no seed transmission of this viroid. However, ASSVd was transmitted at a low rate under field conditions to adjacent trees.