Increased Expression of AQP 1 and AQP 5 in Rat Lungs Ventilated with Low Tidal Volume is Time Dependent

Background and GoalsMechanical ventilation (MV) can induce or worsen pulmonary oedema. Aquaporins (AQPs) facilitate the selective and rapid bi-directional movement of water. Their role in the development and resolution of pulmonary oedema is controversial. Our objectives are to determine if prolonged MV causes lung oedema and changes in the expression of AQP 1 and AQP 5 in rats.Methods25 male Wistar rats were subjected to MV with a tidal volume of 10 ml/kg, during 2 hours (n = 12) and 4 hours (n = 13). Degree of oedema was compared with a group of non-ventilated rats (n = 5). The expression of AQP 1 and AQP 5 were determined by western immunoblotting, measuring the amount of mRNA (previously amplified by RT-PCR) and immunohistochemical staining of AQPs 1 and 5 in lung samples from all groups.ResultsLung oedema and alveolar-capillary membrane permeability did not change during MV. AQP-5 steady state levels in the western blot were increased (p<0.01) at 2 h and 4 h of MV. But in AQP-1 expression these differences were not found. However, the amount of mRNA for AQP-1 was increased at 2 h and 4 h of MV; and for AQP 5 at 4 h of MV. These findings were corroborated by representative immunohistochemical lung samples.ConclusionIn lungs from rats ventilated with a low tidal volume the expression of AQP 5 increases gradually with MV duration, but does not cause pulmonary oedema or changes in lung permeability. AQPs may have a protective effect against the oedema induced by MV

Neurons of the Dentate Molecular Layer in the Rabbit Hippocampus

The molecular layer of the dentate gyrus appears as the main entrance gate for information into the hippocampus, i.e., where the perforant path axons from the entorhinal cortex synapse onto the spines and dendrites of granule cells. A few dispersed neuronal somata appear intermingled in between and probably control the flow of information in this area. In rabbits, the number of neurons in the molecular layer increases in the first week of postnatal life and then stabilizes to appear permanent and heterogeneous over the individuals’ life span, including old animals. By means of Golgi impregnations, NADPH histochemistry, immunocytochemical stainings and intracellular labelings (lucifer yellow and biocytin injections), eight neuronal morphological types have been detected in the molecular layer of developing adult and old rabbits. Six of them appear as interneurons displaying smooth dendrites and GABA immunoreactivity: those here called as globoid, vertical, small horizontal, large horizontal, inverted pyramidal and polymorphic. Additionally there are two GABA negative types: the sarmentous and ectopic granular neurons. The distribution of the somata and dendritic trees of these neurons shows preferences for a definite sublayer of the molecular layer: small horizontal, sarmentous and inverted pyramidal neurons are preferably found in the outer third of the molecular layer; vertical, globoid and polymorph neurons locate the intermediate third, while large horizontal and ectopic granular neurons occupy the inner third or the juxtagranular molecular layer. Our results reveal substantial differences in the morphology and electrophysiological behaviour between each neuronal archetype in the dentate molecular layer, allowing us to propose a new classification for this neural population

Role of age and comorbidities in mortality of patients with infective endocarditis

[Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. [Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. [Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. [Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group

Scaffold-like structures in mouse chromosomes revealed by restriction endonuclease digestion and electron microscopy

4 p.-2 fig.A scaffold-like structure is observed under the electron microscope when mouse chromosomes are digested with the restriction endonuclease Hae III. This structure, located in the inner part of chromatids, may correspond to those fragments of chromatin loops anchored to the chromosome scaffold and is obtained when chromosomes are treated either in suspension or attached to grids. The width of the structure is correlated with the extent of digestion in chromosomes treated in suspension. Those treated on grids show this structure whenever chromatids do not collapse. These results agree with the model of chromosome organization based on a non-histone protein scaffold.This work has been supported by grants PB 86-0106, PB 023602 and 2409/83 from the "Direction General de Investigaci6n Cientifica y Técnica" (Spain).Peer reviewe

Molecular Characterization of Disease-Associated Streptococci of the Mitis Group That Are Optochin Susceptible

Eight optochin-susceptible (Opt(s)) alpha-hemolytic (viridans) streptococcus isolates were characterized at the molecular level. These isolates showed phenotypic characteristics typical of both viridans streptococci and Streptococcus pneumoniae. Comparison of the sequence of housekeeping genes from these isolates with those of S. pneumoniae, Streptococcus mitis, Streptococcus oralis, and Streptococcus pseudopneumoniae suggested that the Opt(s) isolates corresponded to streptococci of the mitis group. Besides, the Opt(s) streptococci were negative by a Gen-Probe AccuProbe pneumococcus test and hybridized with specific pneumococcal probes (lytA and ply) but also with ant, a gene not present in most S. pneumoniae strains. Moreover, the isolates were insoluble in 1% sodium deoxycholate but completely dissolved in 0.1% deoxycholate. Sequence analysis of the lytA gene revealed that the Opt(s) streptococci carried lytA alleles characteristic of those present in nonpneumococcal streptococci of the mitis group. The determination of the partial nucleotide sequence embracing the atp operon encoding the F(o)F(1) H(+)-ATPase indicated that the optochin susceptibility of the isolates was due to the acquisition of atpC, atpA, and part of atpB from S. pneumoniae by horizontal gene transfer

Magnetic Phase Diagram of Nanostructured Zinc Ferrite as a Function of Inversion Degree δ

Magnetic properties of spinel zinc ferrites are strongly linked to the synthesis method and the processing route since they control the microstructure of the resulting material. In this work, ZnFeO nanoparticles were synthesized by the mechanochemical reaction of stoichiometric ZnO and α-FeO, and single-phase ZnFeO was obtained after 150 h of milling. The as-milled samples, with a high inversion degree, were subjected to different thermal annealings up to 600 °C to control the inversion degree and, consequently, the magnetic properties. The as-milled samples, with a crystallite size of 11 nm and inversion degree δ= 0.57, showed ferrimagnetic behavior even above room temperature, as shown by Rietveld refinements of the X-ray diffraction pattern and superconducting quantum interference device magnetometry. The successive thermal treatments at 300, 400, 500, and 600 °C decrease δfrom 0.57 to 0.18, affecting the magnetic properties. A magnetic phase diagram as a function of δcan be inferred from the results: For δ 0.5, a new antiferromagnetic order appeared due to the overpopulation of nonmagnetic Zn on octahedral sites that leads to equally distributed magnetic cations in octahedral and tetrahedral sites.This work was supported by grants from the Spanish Ministry of Science and Innovation MAT2015- 67557-C2-1-P