Generation and Applications of Human Pluripotent Stem Cells Induced into Neural Lineages and Neural Tissues

Human pluripotent stem cells (hPSCs) represent a new and exciting field in modern medicine, now the focus of many researchers and media outlets. The hype is well-earned because of the potential of stem cells to contribute to disease modeling, drug screening, and even therapeutic approaches. In this review, we focus first on neural differentiation of these cells. In a second part we compare the various cell types available and their advantages for in vitro modeling. Then we provide a “state-of-the-art” report about two major biomedical applications: (1) the drug and toxicity screening and (2) the neural tissue replacement. Finally, we made an overview about current biomedical research using differentiated hPSCs

Description of two Enterococcus strains isolated from traditional Peruvian artisanal-produced cheeses with a bacteriocin-like inhibitory activity

The aim of this work was to isolate and to characterize strains of lactic acid bacteria (LAB) with bacteriocin-like inhibitory activity from 27 traditional cheeses artisanal-produced obtained from different Peruvian regions. Twenty Gram+ and catalasenegative strains among 2,277 isolates exhibited bacteriocin-like inhibitory activity against Listeria monocytogenes CWBIB2232 as target strain. No change in inhibitory activity was observed after organic acid neutralization and treatment with catalase of the cell-free supernatant (CFS). The proteinic nature of the antimicrobial activity was confirmed for the twenty LAB strains by proteolytic digestion of the CFS. Two strains, CWBI-B1431 and CWBI-B1430, with the best antimicrobial activity were selected for further researches. These strains were taxonomically identified by phenotypic and genotypic analyses as Enterococcus mundtii (CWBI-B1431) and Enterococcus faecium (CWBI-B1430). The two strains were sensitive to vancomycin (MIC 2 μg.ml-1) and showed absence of haemolysis

Assessment of the physiological and biochemical characterization of a Lactic acid bacterium isolated from chicken faeces in sahelian region

The aim of this work was the examination of the microbiological and technological properties of a lactic acid bacterium (CWBI-B623) isolated from chicken faeces in sahelian region (Burkina Faso). The strain CWBI-B623 is a Gram positive rod, asporogenous, catalase-positive, facultatively anaerobic, non motile and mesophilic. The analysis showed that it produce L(+)-lactic acid via homofermentative pathway and it was able to ferment an important number of the carbohydrates of API 50CHL system. The 16S-rDNAsequence analysis revealed that the isolate was phylogenetically a member of the genus Lactobacillus and formed a subline within the Lactobacillus casei cluster. The minimal inhibitory concentration of CWBI-B623 for bile salts was higher than 1% and the survival rates to acidity with pH 3.0 and pH 2.5 were 26 and 1.2%, respectively. CWBI-B623 is an Lactobacillus casei species based on its physiological and biochemical properties and it could be a good candidate for probiotic formulations.Key words: Lactic acid bacteria, Lactobacillus, probiotic, biodiversity

The Resistance to Freeze-Drying and to Storage Was Determined as the Cellular Ability to Recover Its Survival Rate and Acidification Activity

The protective effects of the fatty acid composition and membrane action of the acidification activity of two strains of Lactobacillus kept at 20°C were studied. The addition of sorbitol, monosodium glutamate and glycerol during storage is causing the decline of acidification and increased concentrations of unsaturated fatty acids observed in both strains. The addition of sorbitol and monosodium glutamate does not alter the fatty acid composition, whatever the strain, but increases the resistance to freeze-drying of L. plantarum CWBI-B1419 and improves survival during storage. The addition of these preservatives and decreased activity of acidification improves the ratio unsaturated. These results indicate that the survival during storage and freeze-drying resistance are closely related to the composition of membrane fatty acids. This behaviour can be interpreted as an adaptation of L. plantarum B1419-CWBI supplemented by cryoprotectant additives such as sorbitol or monosodium glutamate sorbitol and monosodium glutamate as an additive. L. plantarum CWBI-B1419 presents a greater adaptation to culture conditions than L. paracasei ssp. paracasei LMG9192T

Rapid generation of stable transgenic embryonic stem cell lines using modular lentivectors

Generation of stable transgenic embryonic stem (ES) cell lines by classic transfection is still a difficult task, requiring time-consuming clonal selection, and hampered by clonal artifacts and gene silencing. Here we describe a novel system that allows construction of lentivectors and generation of stable ES cell lines with > 99% transgene expression within a very short time frame. Rapid insertion of promoters and genes of interest is obtained through a modular recombinational cloning system. Vectors contain central polypurine tract from HIV-1 element and woodchuck hepatitis virus post-transcriptional regulatory element as well as antibiotic resistance to achieve optimal and homogenous transgene expression. We show that the system 1) is functional in mouse and human ES cells, 2) allows the generation of ES cells expressing genes of interest under the control of ubiquitous or tissue-specific promoters, and 3) allows ES cells expressing two constructs through selection with different antibiotics to be obtained. The technology described herein should become a useful tool in stem cell research

South Atlantic intermediate water advances into the North-east Atlantic with reduced Atlantic meridional overturning circulation during the last glacial period

The Nd isotopic composition (epsilon Nd) of seawater and cold-water coral (CWC) samples from the Gulf of Cadiz and the Alboran Sea, at a depth of 280-827 m were investigated in order to constrain middepth water mass dynamics within the Gulf of Cadiz over the past 40 ka. epsilon Nd of glacial and Holocene CWC from the Alboran Sea and the northern Gulf of Cadiz reveals relatively constant values (-8.6 to -9.0 and -9.5 to -10.4, respectively). Such values are similar to those of the surrounding present-day middepth waters from the Mediterranean Outflow Water (MOW; epsilon Nd approximate to -9.4) and Mediterranean Sea Water (MSW; epsilon Nd approximate to -9.9). In contrast, glacial epsilon Nd values for CWC collected at thermocline depth (550-827 m) in the southern Gulf of Cadiz display a higher average value (-8.90.4) compared to the present-day value (-11.70.3). This implies a higher relative contribution of water masses of Mediterranean (MSW) or South Atlantic origin (East Antarctic Intermediate Water, EAAIW). Our study has produced the first evidence of significant radiogenic epsilon Nd values (approximate to -8) at 19, 23-24, and 27 ka, which are coeval with increasing iceberg discharges and a weakening of Atlantic Meridional Overturning Circulation (AMOC). Since MOW epsilon Nd values remained stable during the last glacial period, it is suggested that these radiogenic epsilon Nd values most likely reflect an enhanced northward propagation of glacial EAAIW into the eastern Atlantic Basin