Amazonian biogenic volatile organic compounds under global change.

Biogenic volatile organic compounds (BVOCs) play important roles at cellular, foliar, ecosystem and atmospheric levels. The Amazonian rainforest represents one of the major global sources of BVOCs, so its study is essential for understanding BVOC dynamics. It also provides insights into the role of such large and biodiverse forest ecosystem in regional and global atmospheric chemistry and climate. We review the current information on Amazonian BVOCs and identify future research priorities exploring biogenic emissions and drivers, ecological interactions, atmospheric impacts, depositional processes and modifications to BVOC dynamics due to changes in climate and land cover. A feedback loop between Amazonian BVOCs and the trends of climate and land-use changes in Amazonia is then constructed. Satellite observations and model simulation time series demonstrate the validity of the proposed loop showing a combined effect of climate change and deforestation on BVOC emission in Amazonia. A decreasing trend of isoprene during the wet season, most likely due to forest biomass loss, and an increasing trend of the sesquiterpene to isoprene ratio during the dry season suggest increasing temperature stress-induced emissions due to climate change.

Psychometric properties of the Spanish version of the family-centred practices scale for use with families of young children receiving early childhood intervention.

BACKGROUND: Early childhood intervention (ECI) centres in Spain recently initiated a process of change towards the adoption of family-centred practices (FCPs). Knowledge about the extent to which practitioners' use FCPs is needed. The psychometric properties of the Spanish version of the FCPs scale were examined. METHOD: A convenience sample of 105 families of children with developmental delays attending three different ECI centres in Spain completed the FCPs scale and provided information about the ECI centre characteristics and practices, caregiver self-efficacy beliefs, and family and child demographic information. RESULTS: The Spanish version of the FCP scale was found to be both reliable and valid. FCPs were correlated with self-efficacy beliefs, parents' involvement in their child's ECI program and family decision making. CONCLUSION: The FCP scale provides practitioners with useful information about their practices, but also has capacity-building consequences for families. The study is a first step for examining the use of FCPs in Spain.

Superficial temporal myofascial flap application in temporomandibular joint arthroplasty in a cat.

CASE SUMMARY: A 2-year-old, intact female domestic longhair cat was referred for surgical treatment after diagnosis of closed jaw locking secondarily to right temporomandibular joint ankylosis and left pseudoankylosis. The animal underwent successful surgical management with bilateral excision arthroplasty followed by interposition of a temporal superficial myofascial flap. Immediately after surgery, the full range of lower jaw movement was achieved and normal occlusion was maintained. Ankylosis did not recur in the 1 year postoperative follow-up period. RELEVANCE AND NOVEL INFORMATION: A temporal myofascial flap could be considered as interposition material after temporomandibular joint arthroplasty to avoid postoperative re-ankylosis and mandibular drift. The main advantages of this flap are its autogenous origin, and the ability to maintain separation between the two bones, preserve mobility and disrupt new bone formation.

Direct assessment in bacteria of prionoid propagation and phenotype selection by Hsp70 chaperone.

Protein amyloid aggregates epigenetically determine either advantageous or proteinopathic phenotypes. Prions are infectious amyloidogenic proteins, whereas prionoids lack infectivity but spread from mother to daughter cells. While prion amyloidosis has been studied in yeast and mammalian cells models, the dynamics of transmission of an amyloid proteinopathy has not been addressed yet in bacteria. Using time-lapse microscopy and a microfluidic set-up, we have assessed in Escherichia coli the vertical transmission of the amyloidosis caused by the synthetic bacterial model prionoid RepA-WH1 at single cell resolution within their lineage context. We identify in vivo the coexistence of two strain-like types of amyloid aggregates within a genetically identical population and a controlled homogeneous environment. The amyloids are either toxic globular particles or single comet-shaped aggregates that split during cytokinesis and exhibit milder toxicity. Both segregate and propagate in sublineages, yet show interconversion. ClpB (Hsp104) chaperone, key for spreading of yeast prions, has no effect on the dynamics of the two RepA-WH1 aggregates. However, the propagation of the comet-like species is DnaK (Hsp70)-dependent. The bacterial RepA-WH1 prionoid thus provides key qualitative and quantitative clues on the biology of intracellular amyloid proteinopathies.

Catéteres venosos centrales permanentes tunelizados para hemodiálisis: estudio de recirculación y dosis de diálisis con líneas normales e invertidas / Permanent tunnelled central venous catheters for haemodialysis: study of recirculation and dialysis dose with normal and inverted lines

Introducción: Los Catéteres Venosos Centrales Permanentes Tunelizados para hemodiálisis presentan con frecuencia una complicación denominada efecto ventana o ventosa, en el que la rama arterial se colapsa en las maniobras de aspiración sin ofrecer resistencia al impeler, determinando la inversión de líneas para poder realizar el tratamiento. El estudio se centra en la relación entre la posición anatómica de las puntas del catéter mediante radiografía de tórax y la recirculación medida con Dilución Ultrasónica, el Porcentaje de Reducción de Urea y el Kt/V, determinados tanto con líneas en posición normal e invertida y a flujos de bomba de 250 y 300 ml/min. Material y método: Estudio Cuasiexperimental. Intrasujeto de 18 meses de duración a n=28 catéteres implantados en 25 pacientes en Hemodiálisis. Resultados: • Recirculación: • Líneas normales a 250 y 300 ml/min: 0,85 ± 2,41% y 1,23 ± 3,14%. • Líneas invertidas a 250 y 300 ml/min; 22,41 ± 12,12% y 24,93 ± 12,09%. • Porcentaje de Reducción de Urea: • Líneas normales a 250 y 300 ml/min; 66,49 ± 8,62% y 70,55 ± 5,30%. • Líneas invertidas a 250 y 300 ml/min; 61,05 ± 8,34% y 62,34 ± 8,68%. • Kt/V: • Líneas normales a 250 y 300 ml/min: 1,31 ± 0,30 y 1,46 ± 0,23%. • Líneas invertidas a 250 y 300 ml/min: 1,10 ± 0,21% y 1,19 ± 0,30%. Discusión: Los Porcentajes de Reducción de Urea y Kt/V con líneas invertidas a ambos flujos estudiados, manifiestan dosis de diálisis adecuadas asumiendo recirculaciones entorno al 20% (AU)

Introduction: Permanent tunnelled central venous catheters for haemodialysis frequently present a complication called the section effect, where the arterial branch collapses in the aspiration manoeuvres without offering resistance when pressed, making it necessary to invert the lines in order to carry out the treatment. The study focuses on the relationship between the anatomical position of the catheter tips using a chest X-ray and recirculation measured by Ultrasound Dilution, the Urea Reduction Ratio and Kt/V, determined both with lines in normal and inverted position and at pump flow rates of 250 and 300 ml/min. Material and method: Quasi-experimental intrasubject study with a duration of 18 months on n=28 catheters implanted in 25 patients undergoing Haemodialysis. Results • Recirculation: • Normal lines at 250 and 300 ml/min: 0.85 ± 2.41% and 1.23 ± 3.14%. • Inverted lines at 250 and 300 ml/min; 22.41 ± 12.12% and 24.93 ± 12.09%. • Urea Reduction Ratio: • Normal lines at 250 and 300 ml/min; 66.49 ± 8.62% and 70.55 ± 5.30%. • Inverted lines at 250 and 300 ml/min; 61.05 ± 8.34% and 62.34 ± 8.68%. • Kt/V: • Normal lines at 250 and 300 ml/min: 1.31 ± 0.30 and 1.46 ± 0.23%. • Inverted lines at 250 and 300 ml/min: 1.10 ± 0.21% and 1.19 ± 0.30%. Discussion: The Urea Reduction Ratios and Kt/V with inverted lines at both flow rates studied show suitable dialysis doses assuming recirculation of around 20% (AU)

Structural analysis of the interactions between hsp70 chaperones and the yeast DNA replication protein Orc4p.

Hsp70 chaperones, besides their role in assisting protein folding, are key modulators of protein disaggregation, being consistently found as components of most macromolecular assemblies isolated in proteome-wide affinity purifications. A wealth of structural information has been recently acquired on Hsp70s complexed with Hsp40 and NEF co-factors and with small hydrophobic target peptides. However, knowledge of how Hsp70s recognize large protein substrates is still limited. Earlier, we reported that homologue Hsp70 chaperones (DnaK in Escherichia coli and Ssa1-4p/Ssb1-2p in Saccharomyces cerevisiae) bind strongly, both in vitro and in vivo, to the AAA+ domain in the Orc4p subunit of yeast origin recognition complex (ORC). ScORC is the paradigm for eukaryotic DNA replication initiators and consists of six distinct protein subunits (ScOrc1p-ScOrc 6p). Here, we report that a hydrophobic sequence (IL(4)) in the initiator specific motif (ISM) in Orc4p is the main target for DnaK/Hsp70. The three-dimensional electron microscopy reconstruction of a stable Orc4p(2)-DnaK complex suggests that the C-terminal substrate-binding domain in the chaperone clamps the AAA+ IL(4) motif in one Orc4p molecule, with the substrate-binding domain lid subdomain wedging apart the other Orc4p subunit. Pairwise co-expression in E. coli shows that Orc4p interacts with Orc1/2/5p. Mutation of IL(4) selectively disrupts Orc4p interaction with Orc2p. Allelic substitution of ORC4 by mutants in each residue of IL(4) results in lethal (I184A) or thermosensitive (L185A and L186A) initiation-defective phenotypes in vivo. The interplay between Hsp70 chaperones and the Orc4p-IL(4) motif might have an adaptor role in the sequential, stoichiometric assembly of ScORC subunits.