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Background Previous studies suggested an elevated risk of venous thromboembolism (VTE) among patients with type 2 diabetes mellitus (T2DM), with a possible sex difference. The impact of glycemic control on the risk of VTE is unclear. Our objective was to analyze the association between glycemic control and the risk of unprovoked (idiopathic) VTE in men and women with T2DM. Methods We conducted a nested case–control analysis (1:4 matching) within a cohort of patients with incident T2DM between 1995 and 2019 using data from the CPRD GOLD. We excluded patients with known risk factors for VTE prior to onset of DM. Cases were T2DM patients with an unprovoked treated VTE. The exposure of interest was glycemic control measured as HbA1c levels. We conducted conditional logistic regression analyses adjusted for several confounders. Results We identified 2′653 VTE cases and 10′612 controls (53.1% females). We found no association between the HbA1c level and the risk of VTE in our analyses. However, when the most recent HbA1c value was recorded within 90 days before the index date, women with HbA1c levels > 7.0% had a 36–55% increased relative risk of VTE when compared to women with HbA1c > 6.5–7.0%. Conclusions Our study raises the possibility that female T2DM patients with HbA1c levels > 7% may have a slightly higher risk for unprovoked VTE compared to women with HbA1c levels > 6.5–7.0%. This increase may not be causal and may reflect differences in life style or other characteristics. We observed no effect of glycemic control on the risk of VTE in men.

Background Surveillance for bovine genetic diseases in Denmark identified a hitherto unreported congenital syndrome occurring among progeny of a Holstein sire used for artificial breeding. A genetic aetiology due to a dominant inheritance with incomplete penetrance or a mosaic germline mutation was suspected as all recorded cases were progeny of the same sire. Detailed investigations were performed to characterize the syndrome and to reveal its cause. Results Seven malformed calves were submitted examination. All cases shared a common morphology with the most striking lesions being severe facial dysplasia and complete prolapse of the eyes. Consequently the syndrome was named facial dysplasia syndrome (FDS). Furthermore, extensive brain malformations, including microencephaly, hydrocephalus, lobation of the cerebral hemispheres and compression of the brain were present. Subsequent data analysis of progeny of the sire revealed that around 0.5% of his offspring suffered from FDS. High density single nucleotide polymorphism (SNP) genotyping data of the seven cases and their parents were used to map the defect in the bovine genome. Significant genetic linkage was obtained for three regions, including chromosome 26 where whole genome sequencing of a case-parent trio revealed two de novo variants perfectly associated with the disease: an intronic SNP in the DMBT1 gene and a single non-synonymous variant in the FGFR2 gene. This FGFR2 missense variant (c.927G>T) affects a gene encoding a member of the fibroblast growth factor receptor family, where amino acid sequence is highly conserved between members and across species. It is predicted to change an evolutionary conserved tryptophan into a cysteine residue (p.Trp309Cys). Both variant alleles were proven to result from de novo mutation events in the germline of the sire. Conclusions FDS is a novel genetic disorder of Holstein cattle. Mutations in the human FGFR2 gene are associated with various dominant inherited craniofacial dysostosis syndromes. Given the phenotypic similarities in FDS affected calves, the genetic mapping and absence of further high impact variants in the critical genome regions, it is highly likely that the missense mutation in the FGFR2 gene caused the FDS phenotype in a dominant mode of inheritance. Electronic supplementary material The online version of this article (doi:10.1186/s12863-017-0541-3) contains supplementary material, which is available to authorized users.

Background When heterologous recombinant proteins are produced in Escherichia coli, they often precipitate to form insoluble aggregates of unfolded polypeptides called inclusion bodies. These structures are associated with chaperones like IbpA. However, there are reported cases of "non-classical" inclusion bodies in which proteins are soluble, folded and active. Results We report that the Brucella abortus PdhS histidine kinase fused to the mCherry fluorescent protein forms intermediate aggregates resembling "non-classical" inclusion bodies when overproduced in E. coli, before forming "classical" inclusion bodies. The intermediate aggregates of PdhS-mCherry are characterized by the solubility of PdhS-mCherry, its ability to specifically recruit known partners fused to YFP, suggesting that PdhS is folded in these conditions, and the quick elimination (in less than 10 min) of these structures when bacterial cells are placed on fresh rich medium. Moreover, soluble PdhS-mCherry foci do not systematically colocalize with IpbA-YFP, a marker of inclusion bodies. Instead, time-lapse experiments show that IbpA-YFP exhibits rapid pole-to-pole shuttling, until it partially colocalizes with PdhS-mCherry aggregates. Conclusion The data reported here suggest that, in E. coli, recombinant proteins like PdhS-mCherry may transit through a soluble and folded state, resembling previously reported "non-classical" inclusion bodies, before forming "classical" inclusion bodies. The dynamic localization of IbpA-YFP foci suggests that the IbpA chaperone could scan the E. coli cell to find its substrates.

Background Polar overdominance at the ovine callipyge (CLPG) locus involves the post-transcriptional trans-inhibition of DLK1 in skeletal muscle of CLPG/CLPG sheep. The abundant maternally expressed microRNAs (miRNAs) mapping to the imprinted DLK1-GTL2 domain are prime candidate mediators of this trans-effect. Results We have tested the affinity of 121 miRNAs processed from this locus for DLK1 by co-transfecting COS1 cells with a vector expressing the full-length ovine DLK1 with corresponding mimic miRNAs. None of the tested miRNAs was able to down regulate DLK1 to the extent observed in vivo. Conclusions This suggests that other factors, with or without these miRNAs, are involved in mediating the observed trans-effect. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-944) contains supplementary material, which is available to authorized users.

Background: Blood lipids are cardiovascular health indicators. High LDL cholesterol values and/or high total cholesterol (TC)/HDL cholesterol ratios are positively related with cardiovascular mortality. Evidence suggests that a Mediterranean diet can reduce the incidence of cardiovascular diseases. Adherence to the Mediterranean diet is often measured by the Mediterranean Diet Score (MDS). However, the association between the Mediterranean diet and blood lipid profiles seems still inconclusive. The aim of this study was to investigate the relationship between the MDS, its different components and blood lipid profiles. Methods: A sample of 506 women and 707 men (aged 18-75 years) was recruited. Three-day diet records were used to calculate the MDS. Blood samples were analyzed for serum TC, LDL and HDL cholesterol. ANOVA was used to analyze blood lipids across the MDS tertiles. A multivariate linear regression analysis was performed to investigate the associations between the MDS, its components and blood lipids, adjusted for several confounders. All analyses were stratified by gender. Results: Few gender-specific associations were found between the MDS, its components and blood lipids. Only in men, the total MDS was negatively related with LDL cholesterol and the ratio TC/HDL cholesterol while positively with HDL cholesterol. In women, respectively two (MUFA/SFA and cereals) and in men three (fruits & nuts, meat and alcohol) of the nine MDS components were related with blood lipids. Conclusions: Analyses investigating the relationship between the MDS, its components and blood lipid profiles indicate only limited influence of the Mediterranean diet on blood lipids. More associations were detected in men compared to women.

Background L(-)-carnitine production has been widely studied because of its beneficial properties on various diseases and dysfunctions. Enterobacteria possess a specific biotransformation pathway which can be used for the enantioselective production of L(-)-carnitine. Although bioprocesses catalyzed by enzymes or whole cells can overcome the lack of enantioselectivity of chemical methods, current processes for L(−)-carnitine production still have severe disadvantages, such as the low yields, side reactions and the need of high catalyst concentrations and anaerobic conditions for proper expression of the biotransformation pathway. Additionally, genetically engineered strains so far constructed for L(-)-carnitine production are based on plasmids and, therefore, suffer from segregational unstability. Results In this work, a stable, high yielding strain for L(-)-carnitine production from low cost substrates was constructed. A metabolic engineering strategy was implemented in a multiple mutant for use in both growing and resting cells systems. The effect of mutations on gene expression and metabolism was analyzed to characterize the productivity constraints of the wild type and the overproducer strains. Precise deletion of genes which encode proteins of central and carnitine metabolisms were performed. Specifically, flux through the TCA cycle was increased by deletion of aceK (which encodes a bifunctional kinase/phosphatase which inhibits isocitrate dehydrogenase activity) and the synthesis of the by-product γ-butyrobetaine was prevented by deletion of caiA (which encodes a crotonobetainyl-CoA reductase). Both mutations led to improve the L(-)-carnitine production by 20 and 42%, respectively. Moreover, the highly regulated promoter of the cai operon was substituted by a constitutive artificial promoter increasing the biotransformation rate, even under aerobic conditions. Resting cells of the BW ΔaceK ΔcaiA p37cai strain produced 59.6 mmol l-1 · h-1 of L(−)-carnitine, doubling the productivity of the wild type strain. In addition, almost total conversion was attained in less than two hours without concomitant production of the side product γ–butyrobetaine. Conclusions L(-)-carnitine production has been enhanced by strain engineering. Metabolic engineering strategies herein implemented allowed obtaining a robust and high yielding E. coli strain. The new overproducer strain attained almost complete conversion of crotonobetaine into L(-)-carnitine with growing and resting cells, and even under aerobic conditions, overcoming the main environmental restriction to carnitine metabolism expression. So far, this is the best performing L(-)-carnitine production E. coli strain described.

Background Gene expression is regulated through a complex interplay of different transcription factors (TFs) which can enhance or inhibit gene transcription. ArcA is a global regulator that regulates genes involved in different metabolic pathways, while IclR as a local regulator, controls the transcription of the glyoxylate pathway genes of the aceBAK operon. This study investigates the physiological and metabolic consequences of arcA and iclR deletions on E. coli K12 MG1655 under glucose abundant and limiting conditions and compares the results with the metabolic characteristics of E. coli BL21 (DE3). Results The deletion of arcA and iclR results in an increase in the biomass yield both under glucose abundant and limiting conditions, approaching the maximum theoretical yield of 0.65 c-mole/c-mole glucose under glucose abundant conditions. This can be explained by the lower flux through several CO2 producing pathways in the E. coli K12 ΔarcAΔiclR double knockout strain. Due to iclR gene deletion, the glyoxylate pathway is activated resulting in a redirection of 30% of the isocitrate molecules directly to succinate and malate without CO2 production. Furthermore, a higher flux at the entrance of the TCA was noticed due to arcA gene deletion, resulting in a reduced production of acetate and less carbon loss. Under glucose limiting conditions the flux through the glyoxylate pathway is further increased in the ΔiclR knockout strain, but this effect was not observed in the double knockout strain. Also a striking correlation between the glyoxylate flux data and the isocitrate lyase activity was observed for almost all strains and under both growth conditions, illustrating the transcriptional control of this pathway. Finally, similar central metabolic fluxes were observed in E. coli K12 ΔarcA ΔiclR compared to the industrially relevant E. coli BL21 (DE3), especially with respect to the pentose pathway, the glyoxylate pathway, and the TCA fluxes. In addition, a comparison of the genome sequences of the two strains showed that BL21 possesses two mutations in the promoter region of iclR and rare codons are present in arcA implying a lower tRNA acceptance. Both phenomena presumably result in a reduced ArcA and IclR synthesis in BL21, which contributes to the similar physiology as observed in E. coli K12 ΔarcAΔiclR. Conclusions The deletion of arcA results in a decrease of repression on transcription of TCA cycle genes under glucose abundant conditions, without significantly affecting the glyoxylate pathway activity. IclR clearly represses transcription of glyoxylate pathway genes under glucose abundance, a condition in which Crp activation is absent. Under glucose limitation, Crp is responsible for the high glyoxylate flux, but IclR still represses transcription. Finally, in E. coli BL21 (DE3), ArcA and IclR are poorly expressed, explaining the similar fluxes observed compared to the ΔarcAΔiclR strain.

Since the Belgian elderly population is expanding at a very high rate, it is important for public health care systems to better understand ageing-related syndromes and diseases, such as sarcopenia. This condition is characterized by a progressive loss of skeletal muscle mass and its action generating capacity (also termed muscle function). Therefore it also implies risk of adverse outcomes like fall-related injury and impaired quality of life. Furthermore, it is well known that both muscle mass and muscle function are under strong genetic determination. However, most previous studies only considered individual associations of one specific gene variant with muscular phenotypes, whereas it is likely several related polymorphisms that combine to influence muscular characteristics. The data of the current study were assessed within the framework of the first (2002-2004) and third (2012-2015) generation Flemish Policy Research Centre Sport. A total of 579 healthy, Flemish Caucasian adults (19-73, 64.4% men) were measured during a follow-up period of ten years. Genomic DNA was extracted and 384 gene variants were genotyped. Force and velocity characteristics of the knee extensors were measured using the Biodex Medical System 3® dynamometer. Furthermore, four genetic predisposition score (GPS) models were designed: a total GPS (based on the sum of all variants, each favorable allele = score 1), a data-driven GPS (sum of favorable alleles of those variants with significant b-coefficients in stepwise regression), a weighted GPS (weighting is done based on the proportion of the variance explained by those variants with significant b-coefficients in stepwise regression) and an elastic-net GPS (sum of favorable alleles included by elastic-net regularization). Afterwards, these GPS models will be compared and used to predict genetic predisposition towards muscle mass and muscle function and its loss by ageing via linear regression analysis.

Background We investigated a potential link between genetic polymorphisms in genes XRCC1 (Arg399Gln), OGG1 (Ser326Cys), XRCC3 (Thr241Met), and XRCC4 (Ile401Thr) with the level of DNA damage and repair, accessed by comet and micronucleus test, in 51 COPD patients and 51 controls. Methods Peripheral blood was used to perform the alkaline and neutral comet assay; and genetic polymorphisms by PCR/RFLP. To assess the susceptibility to exogenous DNA damage, the cells were treated with methyl methanesulphonate for 1-h or 3-h. After 3-h treatment the % residual damage was calculated assuming the value of 1-h treatment as 100%. The cytogenetic damage was evaluated by buccal micronucleus cytome assay (BMCyt). Results COPD patients with the risk allele XRCC1 (Arg399Gln) and XRCC3 (Thr241Met) showed higher DNA damage by comet assay. The residual damage was higher for COPD with risk allele in the four genes. In COPD patients was showed negative correlation between BMCyt (binucleated, nuclear bud, condensed chromatin and karyorrhexic cells) with pulmonary function and some variant genotypes. Conclusion Our results suggest a possible association between variant genotypes in XRCC1 (Arg399Gln), OGG1 (Ser326Cys), XRCC3 (Thr241Met), and XRCC4 (Ile401Thr), DNA damage and progression of COPD.