Disulfide cross-linking of subunits F1-γ and F0I-PVP(b) results in asymmetric effects on proton translocation in the mitochondrial ATP synthase.

AbstractA study is presented on the effect of diamide-induced disulfide cross-linking of F1-γ and F0I-PVP(b) subunits on proton translocation in the mitochondrial ATP synthase. The results show that, upon cross-linking of these subunits, whilst proton translocation from the A side to the B F1 side is markedly accelerated with decoupling of oxidative phosphorylation, proton translocation in the reverse direction, driven by either ATP hydrolysis or a diffusion potential, is unaffected. These observations reveal further peculiarities of the mechanism of energy transfer in the ATP synthase of coupling membranes

Experimental investigation of a helicopter rotor with Gurney flaps

The present work describes an experimental activity carried out to investigate the performance of Gurney flaps on a helicopter rotor model in hovering. The four blades of the articulated rotor model were equipped with Gurney flaps positioned at 95% of the aerofoil chord, spanning 14% of the rotor radius. The global aerodynamic loads and torque were measured for three Gurney flap configurations characterised by different heights. The global measurements showed an apparent benefit produced by Gurney flaps in terms of rotor performance with respect to the clean blade configuration. Particle image velocimetry surveys were also performed on the blade section at 65% of the rotor radius with and without the Gurney flaps. The local velocity data was used to complete the characterisation of the blade aerodynamic performance through the evaluation of the sectional aerodynamic loads using the the control volume approach

Identification of nucleus-encoded F0I protein of bovine heart mitochondrial H+-ATPase as a functional part of the F0 moiety

AbstractThe F0I protein of apparent Mr 27000, previously characterized [(1988) Eur. J. Biochem. 173, 1–8] as a genuine component of bovine heart F0, has been sequenced and shown to be identical with the nucleus encoded 24668 Da protein characterized earlier [(1987) J. Mol. Biol. 197, 89–100]. It is directly shown by proteolytic cleavage and reconstitution experiments that this protein, denoted here as PVP from the single-letter codes of the last three residues of the N-terminus, is involved in proton conduction by F0 and in its sensitivity to oligomycin

Wind-Tunnel Tests of a Tilt-Rotor Aircraft

A wide aerodynamic test campaign has been carried out on the tiltrotor aircraft ERICA at the Large Wind Tunnel of Politecnico di Milano by means of a modular 1:8 scale model in order to produce a dataset necessary to better understand the aerodynamic behaviour of the aircraft and to state its definitive design. The target of the tests was the measurement of the aerodynamic forces and moments in several different configurations and different attitudes. The test program included some conditions at very high incidence and sideslip angles that typically belong to the helicoptermode flight envelope and measurements of forces on the tail and on the tilting wings. A large amount of data has been collected that will be very useful to refine the aircraft design. In general the aircraft aerodynamics do not present any critical problems, but further optimisation is still possible. From the viewpoint of drag in the cruise configuration, the sponsons of the landing gear seem to be worth some further design refinement since they are responsible for a 20% drag increase with respect to the pure fuselage configuration. On the contrary, the wing fairing has proved to work well when the aircraft longitudinal axis is aligned with the wind, providing just a slight drag increase. Two other interesting aspects are the quite nonlinear behaviour of the side force for the intermediate sideslip angles as well as the noticeable hysteresis in the moment coefficient at very high incidence angles

Impaired ATP-binding cassette transporter A1-mediated sterol efflux from oxidized LDL-loaded macrophages

AbstractWe investigated the interaction of oxidized low density lipoprotein (OxLDL) with the ATP-binding cassette A1 (ABCA1) pathway in J774 macrophages. Cellular efflux to apolipoprotein AI (apo-AI) of OxLDL-derived cholesterol was lower than efflux of cholesterol derived from acetylated low density lipoprotein (AcLDL). ABCA1 upregulation by 8-(4-chlorophenylthio)adenosine 3′:5′-cyclic monophosphate (cpt-cAMP) or 22 (R)-hydroxycholesterol (22-OH) and 9-cis retinoic acid (9cRA) increased the efflux to apo-AI of cellular sterols derived from AcLDL, but not of those from OxLDL. AcLDL, but not OxLDL, induced ABCA1 protein content and activity in J774. However, OxLDL did not influence J774 ABCA1 upregulation by cpt-cAMP or 22-OH/9cRA. We conclude that sterols released to cells by OxLDL are available neither as substrate nor as modulator of ABCA1

Wind-tunnel tests of a heavy-class helicopter optimised for drag reduction

Wind-tunnel tests of a heavy-class helicopter model were carried out to evaluate the effectiveness of several components optimised for drag reduction by computational fluid dynamics analysis. The optimised components included different hub-cap configurations, a fairing for blade attachments and the sponsons. Moreover, the effects of vortex generators positioned on the back ramp were investigated. The optimisation effect was evaluated by comparison of the drag measurements carried out for both the original and the optimised helicopter configurations. The comprehensive experimental campaign involved the use of different measurement techniques. Indeed, pressure measurements and stereo particle image velocimetry surveys were performed to achieve a physical insight about the results of load measurements. The test activity confirms the achievement of an overall reduction of about 6% of the original model drag at cruise attitude

Identification of stably expressed reference small non-coding RNAs for microRNA quantification in high-grade serous ovarian carcinoma tissues

MicroRNAs (miRNAs) belong to a family of small non‐coding RNAs (sncRNAs) playing important roles in human carcinogenesis. Multiple investigations reported miRNAs aberrantly expressed in several cancers, including high‐grade serous ovarian carcinoma (HGS‐OvCa). Quantitative PCR is widely used in studies investigating miRNA expression and the identification of reliable endogenous controls is crucial for proper data normalization. In this study, we aimed to experimentally identify the most stable reference sncRNAs for normalization of miRNA qPCR expression data in HGS‐OvCa. Eleven putative reference sncRNAs for normalization (U6, SNORD48, miR‐92a‐3p, let‐7a‐5p, SNORD61, SNORD72, SNORD68, miR‐103a‐3p, miR‐423‐3p, miR‐191‐5p, miR‐16‐5p) were analysed on a total of 75 HGS‐OvCa and 30 normal tissues, using a highly specific qPCR. Both the normal tissues considered to initiate HGS‐OvCa malignant transformation, namely ovary and fallopian tube epithelia, were included in our study. Stability of candidate endogenous controls was evaluated using an equivalence test and validated by geNorm and NormFinder algorithms. Combining results from the three different statistical approaches, SNORD48 emerged as stably and equivalently expressed between malignant and normal tissues. Among malignant samples, considering groups based on residual tumour, miR‐191‐5p was identified as the most equivalent sncRNA. On the basis of our results, we support the use of SNORD48 as best reference sncRNA for relative quantification in miRNA expression studies between HGS‐OvCa and normal controls, including the first time both the normal tissues supposed to be HGS‐OvCa progenitors. In addition, we recommend miR‐191‐5p as best reference sncRNA in miRNA expression studies with prognostic intent on HGS‐OvCa tissues

Three-Dimensional (3D) Printed Silver Nanoparticles/Alginate/Nanocrystalline Cellulose Hydrogels: Study of the Antimicrobial and Cytotoxicity Efficacy

Here, a formulation of silver nanoparticles (AgNPs) and two natural polymers such as alginate (ALG) and nanocrystalline cellulose (CNC) was developed for the 3D printing of scaffolds with large surface area, improved mechanical resistance and sustained capabilities to promote antimicrobial and cytotoxic effects. Mechanical resistance, water content, morphological characterization and silver distribution of the scaffolds were provided. As for applications, a comparable antimicrobial potency against S. aureus and P. aeruginosa was demonstrated by in vitro tests as function of the AgNP concentration in the scaffold (Minimal Inhibitory Concentration value: 10 mg/mL). By reusing the 3D system the antimicrobial efficacy was demonstrated over at least three applications. The cytotoxicity effects caused by administration of AgNPs to hepatocellular carcinoma (HepG2) cell culture through ALG and ALG/CNC scaffold were discussed as a function of time and dose. Finally, the liquid chromatography-mass spectrometry (LC-MS) technique was used for targeted analysis of pro-apoptotic initiation and executioner caspases, anti-apoptotic and proliferative proteins and the hepatocyte growth factor, and provided insights about molecular mechanisms involved in cell death induction

Reconstrucción del labrum de la cadera con injerto de ligamento redondo de la cabeza femoral. Presentación de un caso y descripción de la técnica quirúrgica

Las lesiones del labrum de la cadera con sustancia insuficiente se pueden tratar con técnicas de aumento, de reconstrucción o con trasplante de tejidos. Si el remanente labral es muy escaso, las opciones reconstructivas serían las más adecuadas. Se presenta el caso de una paciente de 40 años con dos cirugías artroscópicas previas fallidas por lesión labral, que fue sometida a una luxación controlada de cadera, siguiendo la técnica original descrita por Ganz, y a la resección del ligamento redondo de la cabeza femoral para cubrir el defecto del labrum. Según nuestro conocimiento, se trata del primer reporte de reconstrucción labral utilizando el ligamento redondo de la cabeza femoral en nuestro medio. Pese a los resultados poco alentadores en pacientes con cirugías previas, la reconstrucción labral utilizando el ligamento redondo ha mostrado ser una alternativa viable

Morphological and molecular analysis support the identity of Arenaria pycnophylloides (Caryophyllaceae, Arenarieae), and the exclusion of the genera Sabulina from the Argentinian flora

Minuartia altoandina ha sido descrita como una especie endémica para el noroeste argentino, y posteriormente, transferida al género Sabulina. En la presente contribución, sobre la base de observaciones morfológicas y datos moleculares, se propone aquí a Sabulina altoandina como un sinónimo heterotípico de Arenaria pycnophylloides, especie nativa de las regiones altoandinas de Bolivia y del noroeste argentino; y como consecuencia, se excluye al género Sabulina de la Flora Argentina. Por otro lado, se sinonimiza a A. pycnophylloides var. compacta bajo A. pycnophylloides, y, además, el nombre de esta variedad se lectotipifica. Se brinda una descripción morfológica de A. pycnophylloides y se aporta una lámina fotográfica del taxón para facilitar la identificación de la especie. Adicionalmente, se presenta un mapa de distribución de la especie, y se excluye de la Flora de Perú.Minuartia altoandina has been described as an endemic species for northwestern Argentina, and later transferred to the genus Sabulina. In this contribution and based on morphological observations and molecular data, Sabulina altoandina is proposed here as a heterotypic synonym of Arenaria pycnophylloides, a native species to the high Andean regions of Bolivia and northwestern Argentina; as a consequence, the genus Sabulina is excluded from the Argentinian Flora. On the other hand, A. pycnophylloides var. compacta is synonymized under A. pycnophylloides, and in addition, the name of this variety is lectotypified. A morphological description of A. pycnophylloides and a photographic plate of the taxon are provided to facilitate identification of the species. Additionally, a distribution map of the species is provided and is excluded from the Peruvian Flora.Fil: Zanotti, Christian Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Chiarini, Franco Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Von Mering, Sabine. Freie Universität Berlin; AlemaniaFil: Acosta, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentin