Компьютерное моделирование механизмов плавления наночастиц металлов различной формы

The report presents the basic models describing the melting temperature of nanomaterials based on different concepts of the structure of matter. It takes under consideration some drawbacks described models. Methods of computer experiment show the effect of the matrix and forms of nanoparticle on its melting point. Some mechanisms of melting metal nanoparticles of different shapes are described. Thermodynamic models give a qualitative description of the melting temperature of nanomate-rials, not taking into account any impact form nanoparticles, nor matrix in which the nanoparticle is, thus showing that the sample temperature will decrease with decreasing the size of nanoparticles. Statistical models take into account these effects and show that the melting temperature of the nanoparticles can either increase or decrease with decreasing the size of nanoparticles.В работе приведены основные модели описания температуры плавления наноматериалов основанные на различных представлениях о строении вещества. Указаны недостатки описываемых моделей. Методами компьютерного эксперимента показано влияние матрицы и формы наночастицы на ее температуру плавления, предложены механизмы плавления наночастиц металлов различной формы

El sistema del interferón tipo I protege a juveniles de lenguado senegalés (Solea senegalensis) frente a la infección por VHSV

El lenguado senegalés (Solea senegalensis) es susceptible a la infección por el Virus de la Septicemia Hemorrágica Viral (VHSV) bajo condiciones experimentales. El objetivo de este trabajo es determinar el papel del sistema del interferón tipo I de lenguado frente a las infecciones por VHSV. Para llevar a cabo este objetivo se realizó un ensayo en el que el sistema del IFN I de juveniles de lenguado se estimuló con poli I:C. Trascurridas 24 h estos mismos animales se inocularon con una dosis letal de un aislado de VHSV patógeno para lenguado. Los controles utilizados fueron: (I) animales inoculados con VHSV sin previa estimulación con poli I:C, (II) animales inoculados sólo con medio L15 y (III) animales inoculados únicamente con poli I:C.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Urinary proteome analysis at 5-year followup of patients with nonoperated ureteropelvic junction obstruction suggests ongoing kidney remodeling

<p>Purpose: Severe ureteropelvic junction obstruction is treated surgically. However, for milder cases most clinical teams adopt a watchful waiting approach and only operate in the presence of significant decline of renal function combined with severe hydronephrosis. Little is known about the long-term consequences of ureteropelvic junction obstruction.</p> <p>Materials and Methods: Using capillary electrophoresis coupled with mass spectrometry, we analyzed the urinary proteome of 42 patients with ureteropelvic junction obstruction 5 years postoperatively or 5 years following spontaneous resolution.</p> <p>Results: At 5-year followup urinary proteomes were similar between patients with early surgical correction of ureteropelvic junction obstruction and age matched controls. In contrast, urinary proteomes differed significantly between conservatively followed patients and controls. Analyses of the proteomic differences suggested ongoing renal or ureteral remodeling in the conservatively followed patients that was not visible clinically.</p> Conclusions: Long-term followup studies are warranted in patients with ureteropelvic junction obstruction, especially those followed conservatively, to determine whether the observed changes in the urinary proteomes become clinically relevant at a later stage

Computer modeling of the mechanisms of melting metal nanoparticles of different shapes

В работе приведены основные модели описания температуры плавления наноматериалов, основанные на различных представлениях о строении вещества. Указаны недостатки описываемых моделей. Методами компьютерного эксперимента показано влияние матрицы и формы наночастицы на ее температуру плавления, предложены механизмы плавления наночастиц металлов различной формы. Термодинамические модели дают качественное описание температуры плавления наноматериалов, не учитывая влияния ни формы наночастицы, ни матрицы, в которой эта наночастица находится, тем самым показывая, что температура образца будет уменьшаться с уменьшением размера наночастицы. Статистические модели учитывают эти влияния и показывают, что температура плавления наночастиц может как увеличиваться, так и уменьшаться с уменьшением размера наночастицы.The report presents the basic models describing the melting temperature of nanomaterials based on different concepts of the structure of matter. It takes under consideration some drawbacks described models. Methods of computer experiment show the effect of the matrix and forms of nanoparticle on its melting point. Some mechanisms of melting metal nanoparticles of different shapes are described. Thermodynamic models give a qualitative description of the melting temperature of nanomate-rials, not taking into account any impact form nanoparticles, nor matrix in which the nanoparticle is, thus showing that the sample temperature will decrease with decreasing the size of nanoparticles. Statistical models take into account these effects and show that the melting temperature of the nanoparticles can either increase or decrease with decreasing the size of nanoparticles

Computer modeling of the mechanisms of melting metal nanoparticles of different shapes

The report presents the basic models describing the melting temperature of nanomaterials based on different concepts of the structure of matter. It takes under consideration some drawbacks described models. Methods of computer experiment show the effect of the matrix and forms of nanoparticle on its melting point. Some mechanisms of melting metal nanoparticles of different shapes are described.В работе приведены основные модели описания температуры плавления наноматериалов основанные на различных представлениях о строении вещества. Указаны недостатки описываемых моделей. Методами компьютерного эксперимента показано влияние матрицы и формы наночастицы на ее температуру плавления, предложены механизмы плавления наночастиц металлов различной формы

Effect of triploidy on turbot haematology

7 pages, 2 figures, 3 tables.-- PMID: 15914050 [PubMed].This study was carried out to compare key haematological features of diploid (2n) and triploid (3n) turbot as a first step towards the assessment of the ability of 3n turbot to withstand sub-optimal culture conditions. Morphometric indices of erythrocytes were determined on blood smears by light microscopy. Triploidy significantly (P < 0.001) increased all morphometric indices measured in the erythrocytes, including size, surface, and volume, except for the size of minor nuclear axis. The increase in cell size was larger for the major (31.0%) than for the minor (8.3%) axis, thus rendering erythrocytes of 3n turbot more ellipsoidal. The increase in erythrocyte volume (45.9%) was close to the theoretical expected 50% increase as a result of one extra chromosome set. Haematological indices were measured automatically by a haematological Coulter Counter. Triploid turbot had lower numbers of red blood cells (RBC: 1.84 cells pL−1 in 2n vs. 1.27 cells pL−1 in 3n; P < 0.001) but they were of a larger size (Mean corpuscular volume [MCV]: 145.51 fL in 2n vs. 181.78 fL in 3n; P < 0.001). However, the decrease in RBC was not compensated by the increase in MCV, and thus, triploidy decreased the haematocrit (Hct: 26.80% in 2n vs. 23.11% in 3n; P < 0.001) and total blood haemoglobin concentration (Hb: 73.74 g l−1 in 2n vs. 67.54 g l−1 in 3n; P < 0.05). In contrast, mean corpuscular hemoglobin (MCH: 40.27 pg in 2n vs. 53.28 pg in 3n; P < 0.001) was higher for 3n turbot as a result of their larger erythrocytes although MCH concentration (MCHC: 0.28 pg fL−1 in 2n vs. 0.29 pg fL−1 in 3n did not significantly differ. RBC, Hct and MCV were also determined manually using light microscopy. In general, discrepancies between the two methods were small (overall not, vert, similar7%) but the Coulter Counter tended to overestimate RBC and Hct (and thus to underestimate MCV). Nevertheless, relative differences between ploidies were very similar, thus verifying triploidy-associated changes in hematological features. These changes, as determined in the present study, are essential when evaluating the feasibility of triploid turbot for intensive aquaculture systems in which unfavorable situations may occur.Peer reviewe

Metabolic alterations derived from absence of Two-Pore Channel 1 at cardiac level.

Two-pore channels (TPCs or TPCNs) are novel voltage-gated ion channels that have been postulated to act as Ca2+ and/or Na+ channels expressed exclusively in acidic organelles such as endosomes and lysosomes. TPCNs participate in the regulation of diverse biological processes and recently have been proposed to be involved in the pathophysiology of metabolic disorders such as obesity, fatty liver disease and type 2 diabetes mellitus. Due to the importance of these pathologies in the development of cardiovascular diseases, we aimed to study the possible role of two-pore channel 1 (TPCN1) in the regulation of cardiac metabolism. To explore the cardiac function of TPCN1, we developed proteomic approaches as 2-DE-MALDI-MS and LC-MALDI-MS in the cardiac left ventricle of TPCN1 KO and WT mice, and found alterations in several proteins implicated in glucose and fatty acid metabolism in TPCN1 KO vs. WT mice. The results confirmed the altered expression of HFABP, a key fatty acid transport protein, and of enolase and PGK1, the key enzymes in the glycolytic process. Finally, in vitro experiments performed in neonatal rat cardiomyocytes, in which TPCN1 was silenced using siRNAs, confirmed that the downregulation of TPCN1 gene expression increased 2-deoxy-D-[3H]-glucose uptake and GLUT4 mobilization into cell peripherals in cardiac cells. Our results are the first to suggest a potential role for TPCNs in cardiac metabolism regulation

Opsonized Virulent Edwardsiella tarda Strains Are Able To Adhere to and Survive and Replicate within Fish Phagocytes but Fail To Stimulate Reactive Oxygen Intermediates

Edwardsiella tarda is responsible for hemorrhagic septicemia (edwardsiellosis) in fish and also causes diseases in higher vertebrates such as birds, reptiles, and mammals, including humans. Interactions of E. tarda with blue gourami phagocytes were studied by light microscopy as well as by adherence, intracellular replication, and superoxide anion assays. Both nonopsonized virulent (PPD130/91 and AL9379) and avirulent (PPD125/87 and PPD76/87) bacteria could adhere to and survive and replicate within phagocytes, while only opsonized virulent strains replicated within the phagocytes. Furthermore, only avirulent E. tarda elicited a higher rate of production of reactive oxygen intermediates (ROIs) by phagocytes, indicating that they were unable to avoid and/or resist reactive oxygen radical-based killing by the fish phagocytes. TnphoA transposon mutagenesis was used to construct a library of 200 alkaline phosphatase (PhoA(+)) fusion mutants from a total of 182,000 transconjugants derived from E. tarda PPD130/91. Five of these mutants induced more ROI production in phagocytes than the wild-type strain. Two mutants had lower replication ability inside phagocytes and moderately higher 50% lethal dose values than the wild-type strain. Sequence analysis revealed that three of these mutants had insertions at sequences having homology to PhoS, dipeptidase, and a surface polymer ligase of lipid A core proteins of other pathogens. These three independent mutations might have changed the cell surface characteristics of the bacteria, which in turn induced phagocytes to produce increased ROIs. Sequences from two other mutants had no homology to known genes, indicating that they may be novel genes for antiphagocytic killing. The present study showed that there are differences in the interactions of virulent and avirulent E. tarda organisms with fish phagocytes and PhoA(+) fusion mutants that could be used successfully to identify virulence genes. The information elucidated here would help in the development of suitable strategies to combat the disease caused by E. tarda