Cryopreservation of Human Pluripotent Stem Cells: Are We Going in the Right Direction?

The first derivation of human embryonic stem cells (hESCs) (Thomson et al., 1998) and the more recently development of human induced pluripotent stem cells (iPSCs) (Park et al., 2008; Takahashi et al., 2007; Takahashi & Yamanaka, 2006; Wernig et al., 2007; Yu et al., 2007) have marked the beginning of a new era in biomedical research. These two types of human pluripotent stem cells (hPSCs) are characterized by an unlimited capacity to selfrenew while retaining their potential to differentiate into almost all cell types of the body (Odorico et al., 2001; Reubinoff et al., 2000; Silva & Smith, 2008). These remarkable properties turn hPSCs into one of the most interesting cell types for toxicology and drug discovery, tissue engineering and regenerative medicine (Battey, 2007; Mountford, 2008). In fact, work with hPSCs has already provided new and exciting developments that may eventually lead to the creation of novel cell-based therapies for the treatment of a wide range of human diseases including Parkinson’s and other neurodegenerative diseases, diabetes, cardiac and vascular diseases (Kiskinis & Eggan, 2010; Ronaghi et al., 2010). However, a major challenge for the widespread application of hPSCs is the development of efficient protocols for cryopreservation..

Human t-DARPP is induced during striatal development

Human Dopamine- and cAMP-regulated phosphoprotein of molecular weight 32 kDa (DARPP-32, also known as PPP1R1B) gene codes for different transcripts that are mainly translated into two DARPP-32 protein isoforms, full length (fl)-DARPP-32 and truncated (t)-DARPP. The t-DARPP lacks the first 36 residues at the N-terminal, which alters its function. In the central nervous system, fl-DARPP-32 is highly expressed in GABAergic striatal medium spiny neurons (MSNs), where it integrates dopaminergic and glutamatergic input signaling. However, no information about human DARPP-32 isoform expression during MSNs maturation is available. In this study, our aim is to determine the expression of the two DARPP-32 isoforms in human fetal and adult striatal samples. We show that DARPP-32 isoform expression is differentially regulated during human striatal development, with the t-DARPP isoform being virtually absent from whole ganglionic eminence (WGE) and highly induced in the adult striatum (in both caudate and putamen). We next compared the four most common anti-DARPP-32 antibodies used in human specimens, to study their recognition of the two isoforms in fetal and adult human striatal samples by western blot and immunohistochemistry. The four antibodies specifically identify the fl-DARPP-32 in both fetal and adult samples, while t-DARPP form was only detected in adult striatal samples. In addition, the lack of t-DARPP recognition in human adult striatum by the antibody generated against the full-length domain produces in turn different efficacy by immunohistochemical analysis. In conclusion, our results show that expression of human DARPP-32 protein isoforms depends on the striatal neurodevelopmental stage with t-DARPP being specific for the human adult striatu

Trade patterns, trade balances and idiosyncratic shocks

International Macroeconomics has long sought an explanation for current account fluctuations that matches the data. The approaches have typically focused on better models and new macroeconomic variables. We demonstrate the limitations of this approach by showing that idiosyncratic shocks are an important cause of macroeconomic volatility even for large countries. When explaining these fluctuations, standard macroeconomic models generally assume that firms are small and that their microeconomic shocks cancel out. We show that the high degree of concentration of bilateral trade flows means that idiosyncratic shocks can have a significant impact on aggregate economic fluctuations. We theoretically develop a descomposition components. Taking the model to data on bilateral trade flows from 1970 to 1997, we find that the most comprehensive macroeconomic model can only account for at most half of the observed variance in trade account volumes of each country. Thus, this paper highlights the importance of considering disaggregated data when modeling the current accoun

Hyaluronic acid-based bioink improves the differentiation and network formation of neural progenitor cells

Introduction: Three-dimensional (3D) bioprinting is a promising technique for the development of neuronal in vitro models because it controls the deposition of materials and cells. Finding a biomaterial that supports neural differentiation in vitro while ensuring compatibility with the technique of 3D bioprinting of a self-standing construct is a challenge. Methods: In this study, gelatin methacryloyl (GelMA), methacrylated alginate (AlgMA), and hyaluronic acid (HA) were examined by exploiting their biocompatibility and tunable mechanical properties to resemble the extracellular matrix (ECM) and to create a suitable material for printing neural progenitor cells (NPCs), supporting their long-term differentiation. NPCs were printed and differentiated for up to 15 days, and cell viability and neuronal differentiation markers were assessed throughout the culture. Results and Discussion: This composite biomaterial presented the desired physical properties to mimic the ECM of the brain with high water intake, low stiffness, and slow degradation while allowing the printing of defined structures. The viability rates were maintained at approximately 80% at all time points. However, the levels of β-III tubulin marker increased over time, demonstrating the compatibility of this biomaterial with neuronal cell culture and differentiation. Furthermore, these cells showed increased maturation with corresponding functional properties, which was also demonstrated by the formation of a neuronal network that was observed by recording spontaneous activity via Ca2+ imaging

Estudi de l'evolució de la climatologia a la Conca de Barberà en els darrers cinquanta anys i les possibles repercussions en la viticultura del segle XXI

L'estudi s'ha dut a terme a Montblanc (capital de la Conca de Barberà). S'han analitzat tendències de temperatures i pluviometries per a cada estadi fenològic de la vinya, amb la finalitat de poder determinar els impactes sobre la viticultura de la zona. La base de dades correspon a l'observatori de Montblanc (coordenades UTM: X: 341.175; Y: 4.584.350; Z: 441 m s. n. m.). La sèrie climàtica de temperatures va des de l'any 1950 fins al 2007 i la pluviometria va des de l'any 1914 fins al 2007. Es poden observar tendències creixents de temperatures màximes i una lleugera pujada de les temperatures mínimes. Les precipitacions disminueixen progressivament cada any i es concentren en determinades èpoques de l'any, per tant, es desestacionalitzen els períodes de pluges, i s'incrementa el dèficit hídric entre la brotada i el verol (és important recalcar que en aquest període l'estrès hídric ha de ser nul).El estudio se ha llevado a cabo en Montblanc (capital de la Conca de Barberà). Se ha analizado tendencias de temperaturas y pluviometrías para cada estado fenológico de la vid, con la finalidad de poder determinar los impactos sobre la viticultura de la zona. La base de datos corresponde al observatorio de Montblanc (coordenadas UTM: X: 341.175; Y: 4.584.350; Z: 441 m s. n. m.) La serie climática de temperaturas va desde el año 1950 hasta el 2007 y la pluviometría va desde el año 1914 hasta el 2007. Se pueden observar tendencias crecientes de temperaturas máximas y una ligera subida de las temperaturas mínimas. Las precipitaciones disminuyen progresivamente cada año y se concentran en determinadas épocas del año, por lo tanto se desestacionalizan los periodos de lluvia y se incrementa el déficit hídrico entre el brote y el envero (es importante recalcar que en este periodo el estrés hídrico ha de ser nulo)

Human embryonic mesenchymal lung-conditioned medium promotes differentiation to myofibroblast and loss of stemness phenotype in lung adenocarcinoma cell lines

Background: When genes responsible for normal embryonic development are abnormally expressed in adults, it can lead to tumor development. This can suggest that the same mechanism that controls embryonic differentiation can also control tumor differentiation. We hypothesize that the malignant phenotype of lung cancer cells could acquire benign characteristics when in contact with an embryonic lung microenvironment. We cultured two lung cancer cell lines in embryonic lung mesenchyme-conditioned medium and evaluated morphological, functional and molecular changes. Methods: The human embryonic mesenchymal lung-conditioned medium (hEML-CM) was obtained by culturing lung cells from embryos in the pseudoglandular stage of development. The NSCLC cell lines A549 and H1299 we cultured in the hEML-CM and in a tumor-conditioned medium. Morphological changes were analyzed with optical and transmission electron microscopy. To evaluate the functional effect of conditioned medium in tumor cells, we analyzed cell proliferation, migration, colony formation capacity in 2D and 3D and in vivo tumor growth capacity. The expression of the pluripotency genes OSKM, the adenocarcinoma marker NKX2-1, the lung surfactant proteins SFTP, the myofibroblast marker MYH and DNMT3A/3B was analyzed with qRT-PCR and the presence of the myofibroblast markers vimentin and α-SMA with immunofluorescence. Transcriptomic analysis was performed using Affymetrix arrays. Results: The A549 and H1299 cells cultured in hEML-CM lost their epithelial morphology, acquired mesodermal characteristics, and decreased proliferation, migration, and colony formation capacity in 2D and 3D, as well as reduced its capacity to growth in vivo. The expression of OSKM, NKX2-1 and SFTP decreased, while that of DNMT3A/3B, vimentin, α-SMA and MYH increased. Distant matrix analysis based on transcriptomic profile showed that conditioned cells were closer to myoblast and human lung fibroblast than to normal epithelial immortalized lung cells. A total of 1631 for A549 and 866 for H1299 differentially expressed genes between control and conditioned cells were identified. Conclusions: To the best of our knowledge, this is the first study to report that stimuli from the embryonic lung can modulate the malignant phenotype of lung cancer cells, control their growth capacity and activate their differentiation into myofibroblasts. These findings could lead to new strategies for lung cancer management

Disruption of striatal glutamatergic transmission induced by mutant huntingtin involves remodelling of both postsynaptic density and NMDA receptor signalling

We study the striatal susceptibility to NMDA receptor (NMDAR)-mediated injury of two Huntington’s disease (HD) transgenic mice:R6/1 and R6/1:BDNF+/−. We found that R6/1:BDNF+/− mice – whichexpress reduced levels of BDNF – were more resistant than R6/1 miceto intrastriatal injection of quinolinate. This increased resistance isrelated to a differential reduction in expression of NMDAR scaffoldingproteins, MAGUKs (PSD-95, PSD-93, SAP-102 and SAP-97) but notto altered levels or synaptic location of NMDAR. A robust reorganizationof postsynaptic density (PSD) was detected in HD transgenicmice, shown by a switch of PSD-93 by PSD-95 in PSD. Furthermore,NMDAR signaling pathways were affected by different BDNF levels inHD mice; we found a reduction of synaptic αCaMKII (but not ofnNOS) in R6/1:BDNF+/− compared to R6/1 mice. The specific regulationof MAGUKs and αCaMKII in striatal neurons may reflect aprotective mechanism against expression of mutant huntingtin exon-1

CD200 is up-regulated in R6/1 transgenic mouse model of Huntington's disease

In Huntington's disease (HD), striatal medium spiny neurons (MSNs) are particularly sensitive to the presence of a CAG repeat in the huntingtin (HTT) gene. However, there are many evidences that cells from the peripheral immune system and central nervous system (CNS) immune cells, namely microglia, play an important role in the etiology and the progression of HD. However, it remains unclear whether MSNs neurodegeneration is mediated by a non-cell autonomous mechanism. The homeostasis in the healthy CNS is maintained by several mechanisms of interaction between all brain cells. Neurons can control microglia activation through several inhibitory mechanisms, such as the CD200-CD200R1 interaction. Due to the complete lack of knowledge about the CD200-CD200R1 system in HD, we determined the temporal patterns of CD200 and CD200R1 expression in the neocortex, hippocampus and striatum in the HD mouse models R6/1 and HdhQ111/7 from pre-symptomatic to manifest stages. In order to explore any alteration in the peripheral immune system, we also studied the levels of expression of CD200 and CD200R1 in whole blood. Although CD200R1 expression was not altered, we observed and increase in CD200 gene expression and protein levels in the brain parenchyma of all the regions we examined, along with HD pathogenesis in R6/1 mice. Interestingly, the expression of CD200 mRNA was also up-regulated in blood following a similar temporal pattern. These results suggest that canonical neuronal-microglial communication through CD200-CD200R1 interaction is not compromised, and CD200 up-regulation in R6/1 brain parenchyma could represent a neurotrophic signal to sustain or extend neuronal function in the latest stages of HD as pro-survival mechanism