Human chorionic villus mesenchymal stromal cells reveal strong endothelial conversion properties

Chorion, amnion and villi are reservoirs of mesenchymal stromal cells (StC) and the hypothesis that StC from fetal tissues retain higher plasticity compared to adult StC has been suggested. Aimed at investigating this aspect, a series of in vitro experiments were performed with StC isolated from first trimester human chorionic villi (CVStC). CVStC were cultured in: (i) standard mesenchymal medium (MM) and (ii) AmniomaxII? (AM), specifically designed to grow amnion-derived cells in prenatal diagnostic procedures. Cells were then exposed to distinct differentiation treatments and distinguished according to morphology, immunophenotype and molecular markers. Human StC obtained from adult bone marrow (BMStC) were used as control. CVStC cultured either in MM or AM presented stromal morphology and immunophenotype, were negative for pluripotency factors (Nanog, Oct-4 and Sox-2), lacked detectable telomerase activity and retained high genomic stability. In AM, however, CVStC exhibited a faster proliferation rate compared to BMStC or CVStC kept in MM. During differentiation, CVStC were less efficient than BMStC in acquiring adipocytes and osteocytes features; the cardiomyogenic conversion occurred at low efficiency in both cell types. Remarkably, in the presence of pro-angiogenic factors, CVStC reprogrammed toward an endothelial-like phenotype at significantly higher efficiency than BMStC. This effect was particularly evident in CVStC expanded in AM. Mechanistically, the reduced CVStC expression of anti-angiogenic microRNA could support this process. The present study demonstrates that, despite of fetal origin, CVStC exhibit restricted plasticity, distinct from that of BMStC and predominantly directed toward the endothelial lineage.     

New records of rhodolith-forming species (Corallinales, Rhodophyta) from deep water in Espírito Santo State, Brazil

Little is known about the diversity of non-geniculate coralline red algae (Rhodophyta, Corallinophycidae) from deep waters in Brazil. Most surveys undertaken in this country have been carried out in shallow waters. In 1994, however, the REVIZEE program surveyed the sustainable living resources potential of the Brazilian exclusive economic zone to depths of 500?m. In the present study, the rhodolith-forming coralline algae from the continental shelf of Espírito Santo State were identified. Samples were taken from 54 to 60?m depth by dredging during ship cruises in 1997. Three rhodolith-forming species were found: Spongites yendoi (Foslie) Chamberlain, Lithothamnion muelleri Lenormand ex Rosanoff and Lithothamnion glaciale Kjellman. These records extend the distribution ranges of these species into Brazilian waters and extend the depth distribution of non-geniculate coralline red algae into Brazilian water to 58?m.     

Composition and structure of the molluscan assemblage associated with a Cymodocea nodosa bed in south-eastern Spain: seasonal and diel variation

The molluscan taxocoenosis associated with a Cymodocea nodosa seagrass bed was studied throughout 1?year in Genoveses Bay, in the MPA “Parque Natural Cabo de Gata-Níjar” (south-eastern Spain). A total of 64,824 individuals were collected and 54 species identified. The molluscan fauna was mainly composed of gastropods (99.56% of individuals, 43 spp.). The families Rissoidae (72.98%, 11 spp.) and Trochidae (16.93%, 7 spp.) were the most abundant and diversified in terms of number of species. Rissoa monodonta (47.1% dominance), Rissoa membranacea (25.1%) and Gibbula leucophaea (11.6%) proved the top dominant species in both diurnal and nocturnal samples. Bivalves (0.41%, 10 species) and cephalopods (0.03%, 1 species) represented only a low percentage of the molluscan taxocoenosis. The molluscan assemblage was mainly composed of species with a wide geographical distribution in Europe, followed by strictly Mediterranean species. The abundance was significantly higher in the cold (December, March) than in the warm months (June, July). Species richness (S) was higher in nocturnal than in diurnal samples, reaching maximal values in diurnal samples of March and June. Shannon–Wiener diversity (H′) values were generally higher in nocturnal samples than in diurnal ones, displaying minimum values in December and June, respectively. Evenness was similar in diurnal and nocturnal samples, with maximum values in July in both groups. S and H′ were also significantly different between diurnal and nocturnal samples. Multivariate analyses based on both qualitative and quantitative data showed a significant seasonal and diel variation. Diel changes revealed to be more distinct than seasonal ones.     

Comparative proteomic analysis reveals insights into anoxic growth of Methyloversatilis universalis FAM5 on methanol and ethanol

Methyloversatilis universalis FAM5 is a facultative methylotrophic bacterium that has been found in a variety of natural and engineered ecosystems. The goal of this study was to investigate M. universalis FAM5 responses to different electron/carbon donors, e.g. methanol or ethanol, during anoxic growth in chemostats with nitrate as the electron acceptor. During steady‐state anoxic growth on either methanol or ethanol, over 90% of the influent nitrate was reduced primarily to nitrite. The cell yield on methanol was lower, possibly due to high energy requirements for C₁ assimilation. Label‐free proteomics further revealed that methanol‐grown cells displayed elevated concentrations of the enzymes involved in C₁ metabolism (H₄MPT/H₄F pathways, formate oxidation and serine cycle). In contrast, C₂ metabolism (glyoxylate shunt and tri‐carboxylic acid cycle) and polyhydroxy‐β‐butyrate (PHB) synthesis related proteins were overrepresented during subsequent growth on ethanol. Notably, the expression of respiratory nitrate reductase was not affected by the carbon sources applied. Furthermore, the changes in the proteome upon switching back to methanol were mostly reversible. Therefore, M. universalis displays wide‐ranging responses to adapt between growth on methanol and ethanol. Such metabolic versatility could be particularly useful in wastewater treatment systems, which need to switch between different electron donors, while still reliably meeting effluent nitrogen discharge goals.     

Expression of lysozymes from Erwinia amylovora phages and Erwinia genomes and inhibition by a bacterial protein

Genes coding for lysozyme-inhibiting proteins (Ivy) were cloned from the chromosomes of the plant pathogens Erwinia amylovora and Erwinia pyrifoliae. The product interfered not only with activity of hen egg white lysozyme, but also with an enzyme from E. amylovora phage ΦEa1h. We have expressed lysozyme genes from the genomes of three Erwinia species in Escherichia coli. The lysozymes expressed from genes of the E. amylovora phages ΦEa104 and ΦEa116, Erwinia chromosomes and Arabidopsis thaliana were not affected by Ivy. The enzyme from bacteriophage ΦEa1h was fused at the N- or C-terminus to other peptides. Compared to the intact lysozyme, a His-tag reduced its lytic activity about 10-fold and larger fusion proteins abolished activity completely. Specific protease cleavage restored lysozyme activity of a GST-fusion. The bacteriophage-encoded lysozymes were more active than the enzymes from bacterial chromosomes. Viral lyz genes were inserted into a broad-host range vector, and transfer to E. amylovora inhibited cell growth. Inserted in the yeast Pichia pastoris, the ΦEa1h-lysozyme was secreted and also inhibited by Ivy. Here we describe expression of unrelated cloned 'silent' lyz genes from Erwinia chromosomes and a novel interference of bacterial Ivy proteins with a viral lysozyme.     

Kinesin-1 prevents capture of the oocyte meiotic spindle by the sperm aster

Centrioles are lost during oogenesis and inherited from the sperm at fertilization. In the zygote, the centrioles recruit pericentriolar proteins from the egg to form a mature centrosome that nucleates a sperm aster. The sperm aster then captures the female pronucleus to join the maternal and paternal genomes. Because fertilization occurs before completion of female meiosis, some mechanism must prevent capture of the meiotic spindle by the sperm aster. Here we show that in wild-type Caenorhabditis elegans zygotes, maternal pericentriolar proteins are not recruited to the sperm centrioles until after completion of meiosis. Depletion of kinesin-1 heavy chain or its binding partner resulted in premature centrosome maturation during meiosis and growth of a sperm aster that could capture the oocyte meiotic spindle. Kinesin prevents recruitment of pericentriolar proteins by coating the sperm DNA and centrioles and thus prevents triploidy by a nonmotor mechanism.     

DNA repair gene expression level in peripheral blood and tumour tissue from non-small cell lung cancer and head and neck squamous cell cancer patients

BackgroundThe nucleotide excision repair pathway is crucial for cellular DNA integrity and the ERCC1 helicase is also potentially involved in resistance to platinum-based chemotherapy, and high levels of ERCC1 mRNA in tumours have been associated with cisplatin resistance in different human cancers. The aim of this work was to investigate the correlation between DNA repair gene expression levels in tumour tissue, normal tissue and peripheral blood samples from patients with two common human cancers, non-small cell lung cancer (NSCLC) and squamous cell carcinoma of the head and neck (HNSCC), to test if blood gene expression could be a proxy for tumour tissue gene expression to predict response to platinum-based chemotherapy.MethodsUsing RT-qPCR we determined ERCC1, ERCC2, ERCC4, XPA, XPC, XRCC1, XRCC3, APEX, OGG1, MGMT mRNA levels in fresh NSCLC, normal lung and HNSCC tissue, as well as blood, from NSCLC and HNSCC patients who were treated surgically.ResultsTarget gene expression in NSCLC and HNSCC tissue was higher than in blood. A statistically significant correlation (p < 0.05) was found between target gene mRNA expression in tumour tissue and blood, in particular ERCC1, MGMT, XPC, XRCC1 and XRCC3 in NSCLC and APEX, ERCC1, ERCC2, ERCC4, XRCC1 and XRCC3 in HNSCC.ConclusionsThe existence of a significant correlation between blood and tumour tissue expression of some genes of clinical interest, such as ERCC1 in NSCLC and HNSCC, could allow the introduction in clinical practice of a simple test that would measure mRNA levels of DNA repair genes in peripheral blood samples instead of tissue samples to determine prognostic and predictive factors in NSCLC and HNSCC patients.     

Chemodiversity of Nonacosan‐10‐ol and n‐Alkanes in the Needle Wax of Pinus heldreichii

This is the first report of individual variability and population diversity of the contents of nonacosan‐10‐ol and n‐alkanes in the needle cuticular waxes of Bosnian pines originated from Montenegro, regarded as Pinus heldreichii var. leucodermis, and from Serbia, regarded as P. heldreichii var. pan?i?i. The amount of nonacosan‐10‐ol varied individually from 27.4 to 73.2% (55.5% in average), but differences between the four investigated populations were not statistically confirmed. The size of the n‐alkanes ranged from C₁₈ to C₃₃. The most abundant n‐alkanes were C₂₃, C₂₇, and C₂₅ (12.2, 11.2, and 10.8% in average, resp.). The carbon preference index (CPI) of the n‐alkanes ranged from 0.8 to 3.1 (1.6 in average), while the average chain length (ACL) ranged from 20.9 to 26.5 (24.4 in average). Long‐chain and mid‐chain n‐alkanes prevailed (49.6 and 37.9% in average, resp.). It was also found that the populations of P. heldreichii var. leucodermis had predominantly a narrower range of n‐alkanes (C₁₈? C₃₁) than the trees of the variety pan?i?i (C₁₈? C₃₃). Differences between the varieties were also significant for most of the other characteristics of the n‐alkane pattern (e.g., most abundant n‐alkanes, CPI, ACL, and relative proportion of short‐, mid‐, and long‐chain n‐alkanes). The principle component and cluster analyses of eleven n‐alkanes confirmed the significant diversity of these two varieties.