Ohdemir0086
KEY POINTS • We described a design-build-test-learn pipeline to construct in vitro biosystems. • The designed system comprised six key enzymes and another three enzymes. • The system converted maltodextrin stoichiometrically to mannitol in one pot.River-bay systems are transitional areas that hold important roles in biogeochemical processes between continents and oceans. However, composition and structure of microbial communities shaped by such environments have not been clear yet. In this study, we used high-throughput sequencing of 16S rRNA genes to analyze the diversity and composition of sediment bacterial communities from the Shenzhen river-bay system during dry and wet seasons. The results showed that sediment bacterial community structure was varied according to habitats (river vs. estuary) and seasons (wet season vs. dry season). The alpha diversity of sediment bacterial community was significantly higher in the dry season than in the wet season, while no significant difference of alpha diversity was found between river and estuary. Neutral community model revealed a significant influence of stochastic processes on sediment bacterial community assembly, especially in the wet season. However, the beta nearest-taxon index indicated that deterministic processes were more responsible for the assembly of sediment bacterial community. Additionally, redundancy analysis suggested strong links between sediment bacterial communities and environmental factors in Shenzhen river-bay system, with the environmental factors explaining 63.5% of the bacterial community variation. Specifically, NH4+, pH, and salinity were the three most important contributing factors that shaped the sediment bacterial communities. Overall, this study provides a valuable reference to get insights into the spatiotemporal pattern of sediment bacterial communities in a typical river-bay system. KEY POINTS • Stochastic processes contribute sediment bacterial community assembly. • Deterministic processes dominate sediment bacterial community assembly. • Environmental factors shape sediment bacterial communities.Cardiovascular diseases are the leading cause of death in the world due to the high incidence of the diseases coupled with the limited therapeutic options. In recent years, advances in regenerative medicine have emerged as a promising treatment. Differentiation of induced pluripotent stem cells (iPSCs) into cardiac cells and emerging technologies allowing arrangement of cells into complex 3D tissue-like structures open new frontiers for transplantation and engraftment of these tissue patches onto the damaged heart. Despite the cells integrating and presenting initial neovascularization, the functional and electric properties of these patches are still not comparable with those of the host cardiac tissue. Future research optimizing maturation and integration of the iPSC-derived cardiomyocytes is paramount for cardiac cell therapy to attain clinical use. Herein, we will review the state of the art and the different approaches to constructing these 3D transplantable structures.Conditional, cell-type-specific transgenic mouse lines are of high value in cardiovascular research. A standard tool for cardiomyocyte-restricted DNA editing is the αMHC-MerCreMer/loxP system. However, there is an ongoing debate on the occurrence of cardiac side effects caused by unspecific Cre activity or related to tamoxifen/oil overload. Here, we investigated potential adverse effects of DNA editing by the αMHC-MerCreMer/loxP system in combination with a low-dose treatment protocol with the tamoxifen metabolite 4-hydroxytamoxifen (OH-Txf). αMHC-MerCreMer mice received intraperitoneally OH-Txf (20 mg/kg) for 5 or 10 days. These treatment protocols were highly efficient to induce DNA editing in adult mouse hearts. Multi-parametric magnetic resonance imaging revealed neither transient nor permanent effects on cardiac function during or up to 19 days after 5 day OH-Txf treatment. Furthermore, OH-Txf did not affect cardiac phosphocreatine/ATP ratios assessed by in vivo 31P MR spectroscopy, indicating no Cre-mediated side effects on cardiac energy status. PI3K inhibitor No MRI-based indication for the development of cardiac fibrosis was found as mean T1 relaxation time was unchanged. Histological analysis of myocardial collagen III content after OH-Txf confirmed this result. Last, mean T2 relaxation time was not altered after Txf treatment suggesting no pronounced cardiac lipid accumulation or tissue oedema. In additional experiments, cardiac function was assessed for up to 42 days to investigate potential delayed side effects of OH-Txf treatment. Neither 5- nor 10-day treatment resulted in a depression of cardiac function. Efficient cardiomyocyte-restricted DNA editing that is free of unwanted side effects on cardiac function, energetics or fibrosis can be achieved in adult mice when the αMHC-MerCreMer/loxP system is activated by the tamoxifen metabolite OH-Txf.Capecitabine is a fluoropyrimidine that is widely used as a cancer drug for the treatment of patients with a variety of cancers. Unfortunately, early onset, severe or life-threatening toxicity is observed in 19-32% of patients treated with capecitabine and 5FU. Dihydropyrimidine dehydrogenase (DPD) is the rate-limiting enzyme in the degradation of 5FU and a DPD deficiency has been shown to be a major determinant of severe fluoropyrimidine-associated toxicity. DPD is encoded by the DPYD gene and some of the identified variants have been described to cause DPD deficiency. Preemptive screening for DPYD gene alterations enables the identification of DPD-deficient patients before administering fluoropyrimidines. In this article, we describe the application of upfront DPD screening in Finnish patients, as a part of daily clinical practice, which was based on a comprehensive DPYD gene analysis, measurements of enzyme activity and plasma uracil concentrations. Almost 8% of the patients (13 of 167 patients) presented with pathogenic DPYD variants causing DPD deficiency. The DPD deficiency in these patients was further confirmed via analysis of the DPD activity and plasma uracil levels. Interestingly, we identified a novel intragenic deletion in DPYD which includes exon 4 in four patients (31% of patients carrying a pathogenic variant). The high prevalence of the exon 4 deletion among Finnish patients highlights the importance of full-scale DPYD gene analysis. Based on the literature and our own experience, genotype preemptive screening should always be used to detect DPD-deficient patients before fluoropyrimidine therapy.
Honokiol, a natural phenolic compound derived from Magnolia plants, is a promising anti-tumor compound that exerts a wide range of anti-cancer effects. Herein, we investigated the effect of honokiol on doxorubicin resistance in breast cancer.
Doxorubicin-sensitive (MCF-7 and MDA-MB-231) and doxorubicin-resistant (MCF-7/ADR and MDA-MB-231/ADR) breast cancer cell lines were treated with doxorubicin in the absence or presence of honokiol; then, the following tests were performed flow cytometry for cell apoptosis, WST-1 assay for cell viability, qPCR and western blot for the expression of miR-188-5p, FBXW7, and c-Myc. MiR-188-5p mimic, miR-188-5p inhibitor, siFBXW7, and c-Myc plasmids were transfected into cancer cells to evaluate whether miR-188-5p and FBXW7/c-Myc signaling are involved in the effect of honokiol on doxorubicin resistance in breast cancer. A dual luciferase reporter system was used to study the direct interaction between miR-188-5p and FBXW7.
Honokiol sensitized doxorubicin-resistant breastuman breast cancer. Our study finds an important role of miR-188-5p in the development of doxorubicin resistance in breast cancer, and enriches our understanding of the mechanism of action of honokiol in cancer therapy.
Circulating serum sclerostin levels are supposed to give agood estimation of the levels of this negative regulator of bone mass within bone. Most studies evaluating total serum sclerostin found different levels in males compared to females and in older compared to younger subjects. Besides an ELISA detecting total sclerostin an ELISA determining bioactive sclerostin has been developed. The aim of this study was to investigate serum levels of bioactive sclerostin in an Austrian population-based cohort.
We conducted across-sectional observational study in 235healthy subjects. Using the bioactive ELISA assay (Biomedica) bioactive sclerostin levels were evaluated.
Serum levels of bioactive sclerostin were higher in men than in women (24%). The levels correlated positively with age (r = 0.47). Apositive correlation could also be detected with body mass index and bone mineral density.
Using the ELISA detecting bioactive sclerostin our results are consistent with data in the literature obtained by different sclerostin assays. The determination of sclerostin concentrations in peripheral blood thus appears to be arobust parameter of bone metabolism.
Using the ELISA detecting bioactive sclerostin our results are consistent with data in the literature obtained by different sclerostin assays. The determination of sclerostin concentrations in peripheral blood thus appears to be a robust parameter of bone metabolism.
Emerging evidence suggests that diet is linked to survival in colorectal cancer patients, although underlying mechanisms are not fully understood. The aim of this study was to evaluate whether dietary exposures are associated with metabolite concentrations in colorectal cancer patients.
Concentrations of 134 metabolites of the Biocrates Absolute
p180 kit were quantified in plasma samples collected at diagnosis from 195 stage I-IV colorectal cancer patients. Food frequency questionnaires were used to calculate adherence to the World Cancer Research Fund (WCRF) dietary recommendations and the Dutch Healthy Diet (DHD15) index as well as to construct dietary patterns using Principal Component Analysis. Multivariable linear regression models were used to determine associations between dietary exposures and metabolite concentrations. All models were adjusted for age, sex, body mass index, smoking status, analytical batch, cancer stage, and multiple testing using false discovery rate.
Participants had a mean (SD) age of 66 (9) years, were mostly men (60%), and mostly diagnosed with stage II and III cancer. For the dietary pattern analyses, Western, Carnivore, and Prudent patterns were identified. Better adherence to the WCRF dietary recommendations was associated with lower concentrations of ten phosphatidylcholines. Higher intake of the Carnivore pattern was associated with higher concentrations of two phosphatidylcholines. The DHD15-index, Western pattern, or Prudent pattern were not associated with metabolite concentrations.
In the current study, the WCRF dietary score and the Carnivore pattern are associated with phosphatidylcholines. Future research should elucidate the potential relevance of phosphatidylcholine metabolism in the colorectal cancer continuum.
ClinicalTrials.gov Identifier NCT03191110.
ClinicalTrials.gov Identifier NCT03191110.
Inulin-type fructans (ITF) are prebiotic dietary fibre (DF) that may confer beneficial health effects, by interacting with the gut microbiota. We have tested the hypothesis that a dietary intervention promoting inulin intake versus placebo influences fecal microbial-derived metabolites and markers related to gut integrity and inflammation in obese patients.
Microbiota (16S rRNA sequencing), long- and short-chain fatty acids (LCFA, SCFA), bile acids, zonulin, and calprotectin were analyzed in fecal samples obtained from obese patients included in a randomized, placebo-controlled trial. Participants received either 16g/d native inulin (prebiotic n = 12) versus maltodextrin (placebo n = 12), coupled to dietary advice to consume inulin-rich versus inulin-poor vegetables for 3months, in addition to dietary caloric restriction.
Both placebo and prebiotic interventions lowered energy and protein intake. A substantial increase in Bifidobacterium was detected afterITF treatment (q = 0.049) supporting our recent data obtained in a larger cohort.
