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Pulmonary artery pseudoaneurysms (PAPs) are rare serious vascular abnormalities mostly due to infections and trauma, although other conditions such as vasculitis, neoplasms, or inflammatory lung diseases can also predispose to this entity. Endovascular techniques such as embolization or covered stent placement have mostly substituted surgical approaches, for their lower invasiveness and greater security, mainly in patients with life-threatening hemoptysis. The purpose of this manuscript is to describe the imaging findings of pulmonary artery pseudoaneurysms and their endovascular management including tips to help interventional radiologists. PAP should be diagnosed as accurately and early as possible in order to prompt endovascular management of further life-threatening hemoptysis. KEY POINTS: • Pulmonary artery pseudoaneurysms (PAPs) are rare serious vascular abnormalities that may represent a life-threatening condition, mainly due to Staphylococcus, Streptococcus, or Mycobacterium tuberculosis. • Radiologists should know the imaging findings of PAP in order to make an accurate and early diagnosis to prompt endovascular management of further life-threatening hemoptysis.

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TITLE: Hemicerebelitis por chikungunya asociado a estado epiléptico refractario en edad pediátrica.

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The study of the interaction between graphene oxide (GO) and arsenic is of great relevance not only in the design of adsorbent materials to remove this contaminant but also in the understanding of its combined nanotoxicity. In this work, we show that As(III) adsorption, primarily H3AsO3, by graphene oxide is affected by its degree of oxidation. Three types of GO with C/O ratios between 1.35 and 1.98 were produced, resulting in important variations in the concentration of COH and COC functional groups. The less oxidized material reached a maximum As(III) adsorption capacity of 123 mg/g, whereas the GO with the highest degree of oxidation reached a value of 288 mg/g at pH 7, the highest reported in the literature. We also show that sulfates and carbonates present in water strongly inhibit As(III) adsorption. The interaction between graphene oxide and As(III) was also studied by Density Functional Theory (DFT) computer models showing that graphene oxide interacts with As(III) primarily through hydrogen bonds, having interaction energies with the hydroxyl and epoxide groups of 1508.6 and 1583.6 kJ/mol, respectively. Finally, cytotoxicity tests showed that the graphene oxide maintained cellular viability of 57% with 50 µg/ml, regardless of its degree of oxidation.

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In two-dimensional turbulent systems the redistribution of energy can be described by quadratic nonlinear three-wave interactions, which are limited by resonance conditions. The set of coupling modes can be understood as resonant manifold. It has been predicted by theory that, in the presence of a shear flow, the resonant manifold in wave-number space shrinks in time favoring large-scale structures. The phenomenon of manifold shrinking in the presence of shear flows is studied the first time experimentally in drift wave turbulence at the stellarator TJ-K by bicoherence analysis. By estimating effective mode numbers characterizing the width of the manifold, it is demonstrated that increasing shear leads to a shrinking of the resonance manifold.

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Hydrogels are versatile materials, finding applications as adsorbers, supports for biosensors and biocatalysts or as scaffolds for tissue engineering. A frequently used building block for chemically cross-linked hydrogels is poly(ethylene glycol) diacrylate (PEG-DA). However, after curing, PEG-DA hydrogels cannot be functionalized easily. In this contribution, the stiff, rod-like tobacco mosaic virus (TMV) is investigated as a functional additive to PEG-DA hydrogels. TMV consists of more than 2000 identical coat proteins and can therefore present more than 2000 functional sites per TMV available for coupling, and thus has been used as a template or building block for nano-scaled hybrid materials for many years. Here, PEG-DA (M n = 700 g mol-1) hydrogels are combined with a thiol-group presenting TMV mutant (TMVCys). By covalent coupling of TMVCys into the hydrogel matrix via the thiol-Michael reaction, the storage modulus of the hydrogels is increased compared to pure PEG-DA hydrogels and to hydrogels containing wildtype TMV (wt-TMV) which is not coupled covalently into the hydrogel matrix. In contrast, the swelling behaviour of the hydrogels is not altered by TMVCys or wt-TMV. Transmission electron microscopy reveals that the TMV particles are well dispersed in the hydrogels without any large aggregates. These findings give rise to the conclusion that well-defined hydrogels were obtained which offer the possibility to use the incorporated TMV as multivalent carrier templates e.g. for enzymes in future studies.

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2,4-Dichlorophenol (2,4-DCP) is considered a priority pollutant due to its high toxicity. Therefore, it is urgent to develop technologies for the disposal of this pollutant. Various remediation processes have been proposed for the elimination of 2,4-DCP in contaminated water, however, most of them involve high costs of operation and maintenance. This study aimed to determine the capacity of remediation of 2,4-DCP in water by Typha latifolia L. wild plants. For that, the tolerance, removal, accumulation and biotransformation of 2,4-DCP by T. latifolia were investigated. The plants were exposed to 2,4-DCP solutions with a concentration range from 1.5 to 300 mgL-1 for 10 days. They exhibited a reduction in chlorophyll levels and growth rate when 2,4-DCP solutions were ≥30 mgL-1 and ≥50 mgL-1, respectively. The removal of contaminant was dose-depended, being 99.7% at 1.5-3 mgL-1, 59-70% at 10-70 mgL-1 and 35-42% at 100-300 mgL-1 of 2,4-DCP in the solution. Studies indicated that 2,4-DCP was mainly accumulated in root tissue rather than in shoot tissue. Acid hydrolysis of biomass extracts suggests 2,4-DCP bioconjugates formation in root tissue as a response mechanism. Additionally, an increment in glutathione S-transferase (GST) activity could indicate a 2,4-DCP conjugation with glutathione as a detoxification mechanism of T. latifolia.

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In vitro cultured cells produce a complex extracellular matrix (ECM) that remains intact after decellularization. The biological complexity derived from the variety of distinct ECM molecules makes these matrices ideal candidates for biomaterials. Biomaterials with the ability to guide cell function are a topic of high interest in biomaterial development. However, these matrices lack specific addressable functional groups, which are often required for their use as a biomaterial. Due to the biological complexity of the cell-derived ECM, it is a challenge to incorporate such functional groups without affecting the integrity of the biomolecules within the ECM. The azide-alkyne cycloaddition (click reaction, Huisgen-reaction) is an efficient and specific ligation reaction that is known to be biocompatible when strained alkynes are used to avoid the use of copper (I) as a catalyst. In our work, the ubiquitous modification of a fibroblast cell-derived ECM with azides was achieved through metabolic oligosaccharide engineering by adding the azide-modified monosaccharide Ac4GalNAz (1,3,4,6-tetra-O-acetyl-N-azidoacetylgalactosamine) to the cell culture medium. The resulting azide-modified network remained intact after removing the cells by lysis and the molecular structure of the ECM proteins was unimpaired after a gentle homogenization process. The biological composition was characterized in order to show that the functionalization does not impair the complexity and integrity of the ECM. The azides within this "clickECM" could be accessed by small molecules (such as an alkyne-modified fluorophore) or by surface-bound cyclooctynes to achieve a covalent coating with clickECM. STATEMENT OF SIGNIFICANCE: The clickECM was produced by the incorporation of azide-functionalized sugar analogues into the extracellular glycans of fibroblast cell cultures by metabolic oligosaccharide engineering. By introducing these azide groups into the glycan structures, we enabled this cell-derived ECM for bioorthogonal click reactions. Click chemistry provides extremely specific reactions with high efficiency, high selectivity, and high reaction yields. We could show that the azide functionalities within the clickECM are chemically accessible. Based on our here described clickECM technique it will be possible to create and investigate new clickECM materials with tunable bioactive properties and additional functionalities, which offers a promising approach for basic and applied research in the field of biomaterial science, biomedical applications, and tissue engineering.

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OBJECTIVE: Examine the presence of functional inducible nitric oxide synthase (iNOS) in lupus nephritis lesions. METHODS: Seventeen kidney biopsies from patients with lupus nephritis and an equal number of normal control kidney biopsies were examined for the presence of iNOS and endothelial nitric oxide synthase (eNOS) and citrulline by using immunohistochemical methods. Additionally, iNOS and eNOS mRNAs were examined by reverse transcription -PCR amplification of total renal RNA. RESULTS: All biopsies expressed constitutive eNOS, but in contrast to normal kidney biopsies, 70% of the lupus biopsies also expressed iNOS mRNA and the cognate protein. Eight positive biopsies corresponded to class IV lupus nephritis, which also had a high degree of citrullination. CONCLUSIONS: The data indicate that functional iNOS activity is present in glomeruli as part of the inflammatory process in the kidney; therefore the products of iNOS could play a role in the pathogenesis of lupus nephritis.

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Este trabajo propone el tratamiento moderno frente a casos moderados o graves de evenenamiento por abejas, mencionando previamente las manifestaciones clínicas y la fisiopatología del apismo, usando la experiencia obtenida en el Hospital "Dr. Leopoldo Manrique Terrero", de Caracas, y el reporte de dos casos con evolución satisfactoria y rápida que presentaron fenómenos de rabdomiolisis

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Introducción. En nuestro país existe escasa información acerca del consumo máximo de oxígeno (VO2max) de nuestra gente. La mayor parte de los datos provienen de pruebas indirectas de laboratorio y campo que no fueron validadas y se ignora su confiabilidad. Propósito. Determinar la validez y confiabilidad de la prueba aeróbica de 1,000 metros, con estudios de laboratorio y campo. Métodos. Participaron 51 sujetos, 31 hombres y 20 mujeres sin contraindicación a pruebas de ejercicio. Todos realizaron cuatro pruebas de ejercicio físico máximo; dos en el laboratorio para medición directa de VO2max sobre una banda sinfín (L1 y L2), y dos pruebas de caminar - correr 1,000 metros (C1 y C2). Los datos fueron analizados con medidas de tendencia central y dispersión, coeficiente de correlación interclase, producto momento de Pearson y pruebas "t". Resultados. El en L1 y L2 fue de 2.67 y 2.70 litros minuto-1 (R = 0.97), y de 43.9 y 43.5 mL kg-1 min-1 (R = 0.97). Para C1 y C2 el VO2max fue de 44.2 y 46.2 mL kg-1 min-1 (R = 0.98). El coeficiente de correlación de Pearson entre las pruebas de laboratorio vs. campo fue de r = 0.88, (p < 0.05). De los datos generados se derivó la ecuación que se propone para estimar VO2max = 71.662 - 5.850 (t). Donde 71.662 y 5.850 son constantes y t = tiempo empleado en caminar - correr 1,000 metros. (P < 0.05). Conclusión. La prueba aeróbica de 1,000 metros es un procedimiento útil y sencillo para estimar el VO2max es la única prueba validada y confiable para mexicanos. Se propone su utilización para otros grupos poblacionales con mayor rango de edad y ambos géneros para validación cruzada.

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The combination of an integrated Mach-Zehnder-interferometer (iMZI) at the bottom of a fluidic microchannel system with supramolecular interfacial binding layers optimized for biosensing purposes is described. The model system used is based on the highly specific interaction of streptavidin to its 'ligand' biotin: a single monolayer of a correspondingly derivatized silane-compound is formed by a self-assembly procedure on top of the channel rib guiding the light through the channels. Injection of a streptavidin solution which leads to the formation of a protein monolayer of d = 2.8 nm in effective thickness results in a phase shift of the sample light relative to the reference channel of delta phi = 6 pi, in good agreement with the theoretical sensitivity of delta phi/delta df = 2.9 pi/nm for a protein layer (n = 1.45) calculated for the device.

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Control over the adsorption of proteins and over the adsorption and spatial orientation of mammalian cells onto surfaces has been achieved by modification of glass and other silicon oxide substrates with poly(N-isopropylacrylamide) (PNIPAM). The functionalization of the substrates was achieved either by a polymer-analogous reaction of aminosilanes with reactive N-(isopropylacrylamide) (NIPAM)-copolymers and by copolymerization of NIPAM with surface-bound methacrylsilane. The obtained coatings were characterized by FT-1R, ellipsometry, and surface plasmon resonance measurements. The adsorption of two proteins-fibrinogen and ribonuclease A-on these surfaces was studied in situ by real time surface plasmon resonance measurements. The PNIPAM-grafted surfaces prepared by either chemical procedure inhibited the adsorption of both proteins. More importantly they prevented the adhesion of neuroblastomaXglioma hybrid cells cultured either in serum-free medium or in a medium containing serum proteins. Deep-UV irradiation was used to perform ablation processes and to create patterns permitting the examination of spatially controlled adhesion and growth of cells. This study showed that patterned ultrathin polymer films on glass are suitable substrates for controlling the interactions of cells with surfaces and are capable of directing the attachment and spreading of cells.

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Thromboembolic events and inadequate palmar collateral circulation are the two main mechanisms of hand ischaemia following radial artery cannulation. The latter cause may be detected in adults with Allen's test, which is difficult to perform and to interpret in children. Therefore we investigated preoperatively in children the permeability of palmar arches with doppler ultrasound, prior to radial artery cannulation. Thirty-five children (20 M/15 F), aged between 6 months and 14 years (mean = 4.2 years) were scheduled for doppler ultrasound study of their palmar arches before undergoing a major neurosurgical procedure. This study was performed with a 8 MHz directional doppler probe according to Marcillon's technique. Blood flow in superficial palmar arch and in pad of the thumb were identified. Alterations in flow caused by compression of the radial artery were noted. Results were expressed in qualitative terms: functional arch (normal doppler), moderately functional or non-functional arch (abnormal doppler). In the latter cases, the artery was not cannulated. An anomaly in one or both palmar arches was seen in 43% of children (95% confidence interval: 25-60%). The incidence was comparable on both sides (right: 34%; left: 31%) with a mean probability of 33% (95% confidence interval: 17-49%). The probability of a controlateral anomaly, when one hand was abnormal, reached 70%, e.g., twice that of the first hand (p < 0.01). This indicates a relatively low incidence of asymmetry (20%) and therefore a high incidence of a bilateral anomaly (23%).(ABSTRACT TRUNCATED AT 250 WORDS)

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Estudio comparativo de la IgA segretora del calostro de 100 madres atendidas en un hospital público (HCV) con el de 60 madres de un hospital privado (CVP) durante el post-parto de 24 a 48 horas, utilizando la extracción manual del calostro, cuantificanción de la Inmunoglobulina A segretora (IgA (s)) mediante la técnica de Inmunodifusión Radial Simple. Se relacionaron las variables: edad materna, número de hijos, control de embarazo, tipo de vivienda, grado de instrucción, ocupación, amamantamiento previo e información del obstetra sobre beneficios de la lactancia materna. Se determinó que los valores de IgA (s) en calostro de las madres del hospital público fueron más elevados que los de las madres del hospital privado (p<0.05). El 58 por ciento de las madres del hospital público tenían educación primaria, el 46.7 por ciento de las del hospital privado tenían educación secundaria. El 98.3 por ciento de las madres del hospital privado tenían control de embarazo. En ambos grupos se observó deficiente información del obstetra sobre la lactancia: 46 por ciento en el centro público y 67.7 por ciento en el privado. Es necesario continuar la investigación en este campo, ya que la lactancia materna debe ser la base para disminuir la morbi-mortalidad por Diarrea Aguda Infantil en las clases más pobres de nuestro país

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D-dimers are specific fibrin degradation products which have been measured in plasma and used as a diagnostic test for deep vein thrombosis of the lower limbs. However, the results published so far have often been conflicting. We compared the results of D-dimer assays by the latex method (positivity threshold: 0.5 microgram/ml) in 3 groups of patients: 22 patients with clinically suspected thrombophlebitis confirmed by doppler ultrasound; 22 patients with clinically suspected thrombophlebitis not confirmed by doppler ultrasound; and 17 hospital patients with other diseases serving as controls. The sensitivity of a D-dimer concentration higher than 0.5 microgram/ml was 96 percent and its specificity 69 percent. In an internal medicine unit where the prevalence of thrombophlebitis was 50 percent, the positive predictive value of a D-dimer concentration higher than 0.5 microgram/ml was 81 percent, and its negative predictive value was 94 percent. Thus, because of its low specificity as compared with imaging methods the D-dimer assay test cannot be used to diagnose deep vein thrombosis, but as it has good sensitivity and is rapidly performed, safe and inexpensive it can be used as an emergency examination which, when negative, makes this diagnosis unlikely.

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