.

Benign Prostatic Hyperplasia (BPH) is the result of excessive cellullar proliferation in the prostatic transition zone, that compresses the urethra, causing the symptoms of the disease. Evidence supports that atherogenic environment could contribute to the development and progression of BPH, increasing its incidence and aggressiveness. The BPH hyperproliferative state requires coordinated communication between the different components that maintain a permissive microenvironment. Thus, extracellular vesicles (EVs) have become relevant as intercellular communication regulators in multiple processes. It has been described that oxidized-LDL molecule (OxLDL) would be involved in numerous signaling pathways; including signaling by EVs promoting cellullar proliferation. EVs, may contain diverse biomolecules that confer them functions in cellular communication. In addition, it has been reported that EVs derived from different cell types are capable to mediate proliferative and inflammatory effects. In this context, we proposed as objectives: 1) to evaluate the effect of OxLDL, simulating an atherogenic state, on cell proliferation in primary cultures of human prostate stromal cells (HPSC) from patient samples (n=8) from the Sanatorio Allende of Córdoba; 2) to isolate EVs from primary cultures by differential ultracentrifugation and analyze their production and release into the medium in treatments with OxLDL vs. vehicle; 3) to morphologically characterize EVs by transmission electron microscopy (TEM) and confirm the identity and presence of exosomes, through CD63 immuno-staining using colloidal gold. It was observed that OxLDL (20μM) produced a significant increase in cell proliferation rate compared to vehicle. EVs were obtained by differential ultracentrifugations (2k, 10k, 150k pellets) and visualized by TEM using negative staining. HPSC from patients with BPH showed a very low frequency of EVs released, with OxLDL inducing a 10-fold increase, especially in the 15-20nm fraction (p<0.001). Ultrastructurally, these EVs exhibited a spherical and concave appearance, compatible with exosomes. Therefore, they were positively verified by CD63 immunostaining. Finally, we conclude that OxLDL would favor cell proliferation, increase and release of EVs, which would participate in cell communication and maintenance of the permissive environment, propitious to progression and increased aggressiveness of BPH.La Hiperplasia Prostática Benigna (HPB) surge a consecuencia de la proliferación celular excesiva de la zona de transición prostática que comprime la uretra, provocando la sintomatología propia de la enfermedad. Evidencias sostienen que el entorno aterogénico podrían contribuir al desarrollo y progresión de la HPB, aumentando su incidencia y agresividad. El estado hiperproliferativo de la HPB requiere una coordinada comunicación entre los diferentes componentes que mantienen un microambiente permisivo. Así, las vesículas extracelulares (EVs) han tomado relevancia como reguladores de comunicación intercelular en múltiples procesos. Se ha descrito que la molécula de LDL-oxidada (OxLDL) estaría involucrada en diversas vías de señalización; incluida la señalización por EVs promoviendo la proliferación celular. Las EVs pueden contener diversas biomoléculas que les confieren funciones en comunicación intercelular y, además, se reportaron efectos proliferativos e inflamatorios mediados por EVs derivadas de distintos tipos celulares. Es este contexto, propusimos como objetivos: 1) evaluar el efecto de OxLDL, simulando un estado aterogénico, sobre la proliferación celular en cultivos primarios de células estromales prostáticas humanas (HPSC) de muestras de pacientes (n=8) del Sanatorio Allende de Córdoba; 2) aislar EVs de cultivos primarios mediante ultracentrifugaciones diferenciales y analizar su producción y liberación al medio en tratamientos con OxLDL vs. vehículo; 3) caracterizar morfológicamente EVs mediante microscopía electrónica de transmisión (TEM) y confirmar la identidad y presencia de exosomas, a través de inmuno-marcación de CD63 utilizando oro coloidal. Se observó que OxLDL (20μM) produjo un aumento significativo en la tasa de proliferación celular respecto al vehículo. EVs fueron obtenidas mediante utracentrifugaciones diferenciales (pellets 2k, 10k, 150k) y visualizadas por TEM utilizando tinción negativa. Las HPSC de pacientes con HPB mostraron una frecuencia muy baja de EVs liberadas, con OxLDL induciendo un aumento de 10 veces, especialmente en la fracción 15-20nm (p<0,001). Ultraestructuralmente, estas EVs exhibieron una apariencia esférica y cóncava, compatible con exosomas; luego fueron verificados positivamente por inmuno-marcación de CD63. Finalmente, podemos concluir que OxLDL favorecería la proliferación celular, incremento y liberación de EVs, las cuales participarían en comunicación celular y mantención del ambiente permisivo propicio para la progresión y aumento de agresividad de la HPB.

Re:Chicago

https://via.library.depaul.edu/museum-publications/1012/thumbnail.jp

Route to achieving perfect B-site ordering in double perovskite thin films

Double perovskites (DP, A$_2$BB’O$_6$) exhibit a breadth of multifunctional properties with a huge potential range of applications, including magneto-optic and spintronic devices. However, spontaneous cation ordering is limited by the similar size and charge of B and B’ cations. We introduce a route to stimulate B-site rock-salt ordering. By growing thin films on (111)-oriented substrates, ‘in-plane’ strain acts on the intrinsically tilted oxygen octahedra of the DP and produces two different B-site cages (in size and shape), stimulating spontaneous cation ordering. For the ferromagnetic insulator La$_2$CoMnO$_6$, clear Co/Mn ordering was achieved by growing on (111)-oriented substrates. The difference in B-site cages was further enhanced when grown under minor (111) in-plane compressive strain, resulting in long-range ordering with a saturation magnetization of 5.8 μB/formula unit (f.u.), close to the theoretical 6 μB/f.u., without antiferromagnetic behavior. Our approach enables the study of many new ordered DPs which have never been made before.This work was supported by the European Research Council (ERC) (Advanced Investigator grant ERC-2009-AdG-247276-NOVOX), the EPSRC (Equipment Account Grant EP/K035282/1) and the Isaac Newton Trust (Minute 13.38(k)). LJ thank the support of the European Union Seventh Framework Programme under Grant Agreement 312483—ESTEEM2 (Integrated Infrastructure Initiative-I3). SuperSTEM is the UK National Facility for Aberration Corrected STEM funded by EPSRC

LRRK2 Phosphorylates Tubulin-Associated Tau but Not the Free Molecule: LRRK2-Mediated Regulation of the Tau-Tubulin Association and Neurite Outgrowth

Leucine-rich repeat kinase 2 (LRRK2), a large protein kinase containing multi-functional domains, has been identified as the causal molecule for autosomal-dominant Parkinson's disease (PD). In the present study, we demonstrated for the first time that (i) LRRK2 interacts with tau in a tubulin-dependent manner; (ii) LRRK2 directly phosphorylates tubulin-associated tau, but not free tau; (iii) LRRK2 phosphorylates tau at Thr181 as one of the target sites; and (iv) The PD-associated LRRK2 mutations, G2019S and I2020T, elevated the degree of tau-phosphorylation. These results provide direct proof that tau is a physiological substrate for LRRK2. Furthermore, we revealed that LRRK2-mediated phosphorylation of tau reduces its tubulin-binding ability. Our results suggest that LRRK2 plays an important role as a physiological regulator for phosphorylation-mediated dissociation of tau from microtubules, which is an integral aspect of microtubule dynamics essential for neurite outgrowth and axonal transport

Timescales of Multineuronal Activity Patterns Reflect Temporal Structure of Visual Stimuli

The investigation of distributed coding across multiple neurons in the cortex remains to this date a challenge. Our current understanding of collective encoding of information and the relevant timescales is still limited. Most results are restricted to disparate timescales, focused on either very fast, e.g., spike-synchrony, or slow timescales, e.g., firing rate. Here, we investigated systematically multineuronal activity patterns evolving on different timescales, spanning the whole range from spike-synchrony to mean firing rate. Using multi-electrode recordings from cat visual cortex, we show that cortical responses can be described as trajectories in a high-dimensional pattern space. Patterns evolve on a continuum of coexisting timescales that strongly relate to the temporal properties of stimuli. Timescales consistent with the time constants of neuronal membranes and fast synaptic transmission (5–20 ms) play a particularly salient role in encoding a large amount of stimulus-related information. Thus, to faithfully encode the properties of visual stimuli the brain engages multiple neurons into activity patterns evolving on multiple timescales

Adult zebrafish as a model organism for behavioural genetics

Recent research has demonstrated the suitability of adult zebrafish to model some aspects of complex behaviour. Studies of reward behaviour, learning and memory, aggression, anxiety and sleep strongly suggest that conserved regulatory processes underlie behaviour in zebrafish and mammals. The isolation and molecular analysis of zebrafish behavioural mutants is now starting, allowing the identification of novel behavioural control genes. As a result of this, studies of adult zebrafish are now helping to uncover the genetic pathways and neural circuits that control vertebrate behaviour

Glutamate and Synaptic Plasticity Systems and Smoking Behavior: Results from a Genetic Association Study

Smoking behavior is a multifactorial phenotype with significant heritability. Identifying the specific loci that influence smoking behavior could provide important etiological insights and facilitate the development of treatments to further reduce smoking related mortality. Although several studies pointed to different candidate genes for smoking, there is still a need for replication especially in samples from different countries. In the present study, we investigated whether 21 positive signals for smoking behavior from these studies are replicated in a sample of 531 blood donors from the Brazilian population. The polymorphisms were chosen based on their representativeness of different candidate biologic systems, strength of previous evidence, location and allele frequencies. By genotyping with the Sequenom MassARRAY iPLEX platform and subsequent statistical analysis using Plink software, we show that two of the SNPs studied, in the SLC1A2 (rs1083658) and ACTN1 (rs2268983) genes, were associated with smoking behavior in our study population. These genes are involved in crucial aspects of nicotine dependence, glutamate system and synaptic plasticity, and as such, are biologically plausible candidates that merit further molecular analyses so as to clarify their potential role in smoking behavior

Temperature Influences Selective Mortality during the Early Life Stages of a Coral Reef Fish

For organisms with complex life cycles, processes occurring at the interface between life stages can disproportionately impact survival and population dynamics. Temperature is an important factor influencing growth in poikilotherms, and growth-related processes are frequently correlated with survival. We examined the influence of water temperature on growth-related early life history traits (ELHTs) and differential mortality during the transition from larval to early juvenile stage in sixteen monthly cohorts of bicolor damselfish Stegastes partitus, sampled on reefs of the upper Florida Keys, USA over 6 years. Otolith analysis of settlers and juveniles coupled with environmental data revealed that mean near-reef water temperature explained a significant proportion of variation in pelagic larval duration (PLD), early larval growth, size-at-settlement, and growth during early juvenile life. Among all cohorts, surviving juveniles were consistently larger at settlement, but grew more slowly during the first 6 d post-settlement. For the other ELHTs, selective mortality varied seasonally: during winter and spring months, survivors exhibited faster larval growth and shorter PLDs, whereas during warmer summer months, selection on PLD reversed and selection on larval growth became non-linear. Our results demonstrate that temperature not only shapes growth-related traits, but can also influence the direction and intensity of selective mortality

The DSIF Subunits Spt4 and Spt5 Have Distinct Roles at Various Phases of Immunoglobulin Class Switch Recombination

Class-switch recombination (CSR), induced by activation-induced cytidine deaminase (AID), can be divided into two phases: DNA cleavage of the switch (S) regions and the joining of the cleaved ends of the different S regions. Here, we show that the DSIF complex (Spt4 and Spt5), a transcription elongation factor, is required for CSR in a switch-proficient B cell line CH12F3-2A cells, and Spt4 and Spt5 carry out independent functions in CSR. While neither Spt4 nor Spt5 is required for transcription of S regions and AID, expression array analysis suggests that Spt4 and Spt5 regulate a distinct subset of transcripts in CH12F3-2A cells. Curiously, Spt4 is critically important in suppressing cryptic transcription initiating from the intronic Sμ region. Depletion of Spt5 reduced the H3K4me3 level and DNA cleavage at the Sα region, whereas Spt4 knockdown did not perturb the H3K4me3 status and S region cleavage. H3K4me3 modification level thus correlated well with the DNA breakage efficiency. Therefore we conclude that Spt5 plays a role similar to the histone chaperone FACT complex that regulates H3K4me3 modification and DNA cleavage in CSR. Since Spt4 is not involved in the DNA cleavage step, we suspected that Spt4 might be required for DNA repair in CSR. We examined whether Spt4 or Spt5 is essential in non-homologous end joining (NHEJ) and homologous recombination (HR) as CSR utilizes general repair pathways. Both Spt4 and Spt5 are required for NHEJ and HR as determined by assay systems using synthetic repair substrates that are actively transcribed even in the absence of Spt4 and Spt5. Taken together, Spt4 and Spt5 can function independently in multiple transcription-coupled steps of CSR