Basic fibroblast growth factor modulates cell cycle of human umbilical cord-derived mesenchymal stem cells.

Background: Mesenchymal stem cells (MSC) have great potential in regenerative medicine, immunotherapy and gene therapy due to their unique properties of self-renewal, high plasticity, immune modulation and ease for genetic modification. However, production of MSC at sufficient clinical scale remains an issue as in vitro generation of MSC inadequately fulfils the demand with respect to patients. Objectives: This study has aimed to establish optimum conditions to generate and characterize MSC from human umbilical cord (UC-MSC). Materials and methods: To optimize MSC population growth, basic fibroblast growth factor (bFGF) was utilized in culture media. Effects of bFGF on expansion kinetics, cell cycle, survival of UC-MSC, cytokine secretion, expression of early stem-cell markers and immunomodulation were investigated. Results: bFGF supplementation profoundly enhanced UC-MSC proliferation by reducing population doubling time without altering immunophenotype and immunomodulatory function of UC-MSC. However, cell cycle studies revealed that bFGF drove the cells into the cell cycle, as a higher proportion of cells resided in S phase and progressed into M phase. Consistent with this, bFGF was shown to promote expression of cyclin D proteins and their relevant kinases to drive UC-MSC to transverse cell cycle check points, thus, committing the cells to DNA synthesis. Furthermore, supplementation with bFGF changed the cytokine profiles of the cells and reduced their apoptotic level. Conclusion: Our study showed that bFGF supplementation of UC-MSC culture enhanced the cells' growth kinetics without compromising their nature

Genomic Islands as a Marker to Differentiate between Clinical and Environmental Burkholderia pseudomallei

Burkholderia pseudomallei, as a saprophytic bacterium that can cause a severe sepsis disease named melioidosis, has preserved several extra genes in its genome for survival. The sequenced genome of the organism showed high diversity contributed mainly from genomic islands (GIs). Comparative genome hybridization (CGH) of 3 clinical and 2 environmental isolates, using whole genome microarrays based on B. pseudomallei K96243 genes, revealed a difference in the presence of genomic islands between clinical and environmental isolates. The largest GI, GI8, of B. pseudomallei was observed as a 2 sub-GI named GIs8.1 and 8.2 with distinguishable %GC content and unequal presence in the genome. GIs8.1, 8.2 and 15 were found to be more common in clinical isolates. A new GI, GI16c, was detected on chromosome 2. Presences of GIs8.1, 8.2, 15 and 16c were evaluated in 70 environmental and 64 clinical isolates using PCR assays. A combination of GIs8.1 and 16c (positivity of either GI) was detected in 70% of clinical isolates and 11.4% of environmental isolates (P<0.001). Using BALB/c mice model, no significant difference of time to mortality was observed between K96243 isolate and three isolates without GIs under evaluation (P>0.05). Some virulence genes located in the absent GIs and the difference of GIs seems to contribute less to bacterial virulence. The PCR detection of 2 GIs could be used as a cost effective and rapid tool to detect potentially virulent isolates that were contaminated in soil

Proteomic profiling of Burkholderia cenocepacia clonal isolates with different virulence potential retrieved from a cystic fibrosis patient during chronic lung infection

Respiratory infections with Burkholderia cepacia complex (Bcc) bacteria in cystic fibrosis (CF) are associated with a worse prognosis and increased risk of death. In this work, we assessed the virulence potential of three B. cenocepacia clonal isolates obtained from a CF patient between the onset of infection (isolate IST439) and before death with cepacia syndrome 3.5 years later (isolate IST4113 followed by IST4134), based on their ability to invade epithelial cells and compromise epithelial monolayer integrity. The two clonal isolates retrieved during late-stage disease were significantly more virulent than IST439. Proteomic profiling by 2-D DIGE of the last isolate recovered before the patient's death, IST4134, and clonal isolate IST439, was performed and compared with a prior analysis of IST4113 vs. IST439. The cytoplasmic and membrane-associated enriched fractions were examined and 52 proteins were found to be similarly altered in the two last isolates compared with IST439. These proteins are involved in metabolic functions, nucleotide synthesis, translation and protein folding, cell envelope biogenesis and iron homeostasis. Results are suggestive of the important role played by metabolic reprogramming in the virulence potential and persistence of B. cenocepacia, in particular regarding bacterial adaptation to microaerophilic conditions. Also, the content of the virulence determinant AidA was higher in the last 2 isolates. Significant levels of siderophores were found to be secreted by the three clonal isolates in an iron-depleted environment, but the two late isolates were more tolerant to low iron concentrations than IST439, consistent with the relative abundance of proteins involved in iron uptake.This work was supported by FEDER and FCT – Fundação para a Ciência e a Tecnologia (contract PEst-OE/EQB/LA0023/2011_ research line: Systems and Synthetic Biology; PhD grant to A.M. – SFRH/BD/37012/2007, and PD grants to S.S. – SFRH/BPD/75483/2010 and C.C. – SFRH/BPD/ 81220/2011. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio

The Helicobacter pylori Genome Project : insights into H. pylori population structure from analysis of a worldwide collection of complete genomes

Helicobacter pylori, a dominant member of the gastric microbiota, shares co-evolutionary history with humans. This has led to the development of genetically distinct H. pylori subpopulations associated with the geographic origin of the host and with differential gastric disease risk. Here, we provide insights into H. pylori population structure as a part of the Helicobacter pylori Genome Project (HpGP), a multi-disciplinary initiative aimed at elucidating H. pylori pathogenesis and identifying new therapeutic targets. We collected 1011 well-characterized clinical strains from 50 countries and generated high-quality genome sequences. We analysed core genome diversity and population structure of the HpGP dataset and 255 worldwide reference genomes to outline the ancestral contribution to Eurasian, African, and American populations. We found evidence of substantial contribution of population hpNorthAsia and subpopulation hspUral in Northern European H. pylori. The genomes of H. pylori isolated from northern and southern Indigenous Americans differed in that bacteria isolated in northern Indigenous communities were more similar to North Asian H. pylori while the southern had higher relatedness to hpEastAsia. Notably, we also found a highly clonal yet geographically dispersed North American subpopulation, which is negative for the cag pathogenicity island, and present in 7% of sequenced US genomes. We expect the HpGP dataset and the corresponding strains to become a major asset for H. pylori genomics

Correlation of plasma C-reactive protein levels to sialic acid and lipid concentrations in the normal population

Aim of this study was to investigate the relationship between sialic acid component and C-reactive protein and lipids in the plasma of 80 healthy subjects. Levels of sialic acid, C-Reactive Protein (CRP) and plasma lipids were measured in a normal population consisting of 80 subjects. The possible correlation between sialic acid and CRP was also studied. The total sialic acid concentration was 2.61±0.61 mM L-1, CRP (2.52±2.32 mmole L-1), total cholesterol (5.504±1.28 mM L-1), triglycerides (1.31±0.87 mM L-1), low density lipoprotein (3.51±1.11 mM L-1) and high density lipoprotein (1.40±0.37 mM L-1). There was a positive correlation between sialic acid and CRP (r = 0.283, p&lt;0.05). However, there was no correlation between CRP and the plasma lipids

Sialic acid and vascular cell adhesion molecule-1 as early markers in the first degree relatives of type 2 diabetes mellitus patients

Levels of sialic acid and Vascular Cell Adhesion Molecule-1 (VCAM-1) in the first degree relatives of type 2 diabetes mellitus patients and their possible role as an early marker of the prediabetic stage were studied in 74 controls and 150 first degree relatives. The total sialic acid concentration was significantly higher (p<0.05) in the first degree relatives compared to the control subjects. Amongst the offsprings, the total sialic acid concentration was significantly higher in the offspring with Normal Glucose Tolerance (NGT) than those with Impaired Glucose Tolerance (IGT). However the level of VCAM-1 did not differ amongst the controls and the first degree relatives. The total cholesterol and triglycerides were significantly higher (p<0.05) in the offspring with IGT when compared to the control subjects and the offspring with NGT. The above data suggests that desialylation of the vascular endothelium is an early event that precedes the expression of IGT or any lipid changes in asymptomatic offspring of one type 2 diabetic parent

Sialic acid and vascular cell adhesion molecule-l as early markers in the first degree relatives of type 2 diabetes mellitus patients

Levels of sialic acid and Vascular Cell Adhesion Molecule-I (VCAM-I)in the first degree relatives of type 2 diabetes mellitus patients and their possible role as an early marker of the prediabetic stage were studied in 74 controls and 150 first degree relatives. The total sialic acid concentration was significantly higher (p<O.05) in the first degree relatives compared to the control subjects. Amongst the offsprings, the total sialic acid concentration was significantly higher in the offspring with Normal Glucose Tolerance (NGT) than those with Impaired Glucose Tolerance (IGT). However the level of VCAM-I did not differ amongst the controls and the first degree relatives. The total cholesterol and triglycerides were significantly higher (p<0.05) in the offspring with IGT when compared to the control subjects and the offspring with NGT. The above data suggests that desialylation of the vascular endothelium is an early event that precedes the expression of IGT or any lipid changes in asymptomatic offspring of one type 2 diabetic parent