Pre-leukemic clones carrying DNMT3A mutations have a selective advantage and an inherent chemo-resistance, however the basis for this phenotype has not been fully elucidated. Mutations affecting the gene TP53 occur in pre-leukemic hematopoietic stem/progenitor cells (preL-HSPCs) and lead to chemo-resistance. Many of these mutations cause a conformational change and some of them were shown to enhance self-renewal capacity of preL-HSPCs. Intriguingly, a misfolded P53 was described in AML blasts that do not harbor mutations in TP53, emphasizing the dynamic equilibrium between wild-type (WT) and "pseudo-mutant" conformations of P53. By combining single cell analyses and P53 conformation-specific monoclonal antibodies we studied preL-HSPCs from primary human DNMT3A-mutated AML samples. We found that while leukemic blasts express mainly the WT conformation, in preL-HSPCs the pseudomutant conformation is the dominant. HSPCs from non-leukemic samples expressed both conformations to a similar extent. In a mouse model we found a small subset of HSPCs with a dominant pseudo-mutant P53. This subpopulation was significantly larger among DNMT3AR882H-mutated HSPCs, suggesting that while a pre-leukemic mutation can predispose for P53 misfolding, additional factors are involved as well. Treatment with a short peptide that can shift the dynamic equilibrium favoring the WT conformation of P53, specifically eliminated preL-HSPCs that had dysfunctional canonical P53 pathway activity as reflected by single cell RNA sequencing. Our observations shed light upon a possible targetable P53 dysfunction in human preLHSPCs carrying DNMT3A mutations. This opens new avenues for leukemia prevention.

Autologous stem cell therapy is the most promising alternative treatment in patients with chronic ischemic diseases, including ischemic heart disease and critical limb ischemia, which are characterized by poor prognosis related to serious impair of quality of life, high risk of cardiovascular events and mortality rates. However, one of the most serious shortcomings of stem cell transplantation are low survival after transplantation to the site of injury, as large number of stem cells are lost within 24 hours after delivery. Multiple studies suggest that combination of lipid-lowering drugs, statins, and stem cell transplantation might improve therapeutic efficacy in regenerative medicine. Statins are inhibitors of HMG-CoA reductase and belong to recommended therapy in all patients suffering from critical limb ischemia. Statins possess non-lipid effects which involve improvement of endothelial function, decrease of vascular inflammation and oxidative stress, anti-cancer and stem cell modulation capacities. These non-lipid effects are explained by inhibition of mevalonate synthesis via blocking isoprenoid intermediates synthesis, such as farnesylpyrophospate and geranylgeranylpyrophospate and result in modulation of the PI3K/Akt pathway. Moreover, statin-mediated microRNA regulation may contribute to the pleiotropic functions. MicroRNA interplay in gene regulatory network of IGF/Akt pathway may be of special significance for the treatment of critical limb ischemia. We assume further studies are needed for detailed analysis of statin interactions with microRNA at the molecular level and their link to PI3K/Akt and IGF/Akt pathway in stem cells, which are currently the most promising treatment strategy used in chronic ischemic diseases.

Sarcoplasmic reticulum (SR) is a specialized tubular network, which not only maintains the intracellular concentration of Ca2+ at a low level but is also known to release and accumulate Ca2+ for the occurrence of cardiac contraction and relaxation, respectively. This subcellular organelle is composed of several phospholipids and different Ca2+-cycling, Ca2+-binding and regulatory proteins, which work in a coordinated manner to determine its function in cardiomyocytes. Some of the major proteins in the cardiac SR membrane include Ca2+-pump ATPase (SERCA2), Ca2+-release protein (ryanodine receptor), calsequestrin (Ca2+-binding protein) and phospholamban (regulatory protein). The phosphorylation of SR Ca2+-cycling proteins by protein kinase A or Ca2+-calmodulin kinase (directly or indirectly) has been demonstrated to augment SR Ca2+-release and Ca2+-uptake activities and promote cardiac contraction and relaxation functions. The activation of phospholipases and proteases as well as changes in different gene expressions under different pathological conditions have been shown to alter the SR composition and produce Ca2+-handling abnormalities in cardiomyocytes for the development of cardiac dysfunction. The post-translational modifications of SR Ca2+ cycling proteins by processes such as oxidation, nitrosylation, glycosylation, lipidation, acetylation, sumoylation, and O GlcNacylation have also been reported to affect the SR Ca2+ release and uptake activities as well as cardiac contractile activity. The SR function in the heart is also influenced in association with changes in cardiac performance by several hormones including thyroid hormones and adiponectin as well as by exercise-training. On the basis of such observations, it is suggested that both Ca2+-cycling and regulatory proteins in the SR membranes are intimately involved in determining the status of cardiac function and are thus excellent targets for drug development for the treatment of heart disease.

Objective: The purpose of this study was to explore the paracrine effects of adipose-derived stem cells (ASCs) on cutaneous wound healing in diabetic rats.

Method: The ASCs were isolated and identified by immunofluorescent staining. The ASCs-conditioned medium (ASCs-CM) was harvested. Cell counting kit (CCK)-8 assay, scratch experiments, western blot and quantitative polymerase chain reaction (qPCR) were performed to observe the effects of ASCs-CM on fibroblasts. A full-thickness skin wound diabetic rat model was prepared, using 34 male, Sprague Dawley rats. ASCs-CM or negative-control medium (N-CM) was injected around the wound surface. The existing wound area was measured on days 4, 8, 12 and 16 after the postoperative day, and the wound tissues were collected for immunohistochemical staining and qPCR quantitative study.

Results: In this experiment, the isolated cells were characterised as ASCs. The results of CCK-8 assay, cell scratch test, western blot and qPCR showed ASCs-CM could significantly promote the proliferation, migration and differentiation of fibroblasts. Simultaneously, the healing rate of full-thickness skin wounds in diabetic rats was significantly higher in the ASCs-CM group than the N-CM group on days 4, 8, 12 and 16. Immunohistochemical staining and qPCR results showed that the expression of vascular endothelial growth factor (VEGF, days 4 and 8), α-smooth muscle actin (SMA) (days 4 and 16), transforming growth factor (TGF)-β1 (days 4, 8 and 12) were higher in the ASCs-CM group than that of the N-CM group (p<0.05).

Conclusion: This experiment demonstrated that ASCs-CM may accelerate wound healing in diabetic rats by promoting the secretion of TGF-β1, VEGF and the proliferation, migration and differentiation of fibroblasts.

Keywords: adipose-derived stem cells; animal model; conditioned medium; diabetes; fibroblasts; wound; wound care; wound healing.

Metabolic syndrome is a prevalent disease resulting from an interplay of genomic component and the exposome. Parental diet has been shown to affect offspring metabolic health via multiple epigenetic mechanisms. Excess carbohydrate intake is one of the driving forces of the obesity and metabolic syndrome pandemics. This review summarizes the evidence for the effects of maternal carbohydrate (fructose, sucrose, glucose) overnutrition on the modulation of metabolic syndrome components in the offspring. Despite substantial discrepancies in experimental design, common effects of maternal carbohydrate overnutrition include increased body weight and hepatic lipid content of the "programmed" offspring. However, the administration of sucrose to several rat models leads to apparently favorable metabolic outcomes. Moreover, there is evidence for the role of genomic background in modulating the metabolic programming effect in the form of nutri-epigenomic interaction. Comprehensive, robust studies are needed to resolve the temporal, sex-specific, genetic, epigenetic and nutritional aspects of parental overnutrition in the intergenerational and transgenerational pathogenesis of metabolic syndrome.

A new theoretical approach is presented and applied for the simulation of Fe(II) low-spin (LS, singlet, t_2g⁶e_g⁰) → high-spin (HS, quintet, t_2g⁴e_g²) photoswitching dynamics of the octahedral model complex [Fe(NCH)₆]²⁺. The utilized synergistic methodology heavily exploits the strengths of complementary electronic structure and spin-vibronic dynamics methods. Specifically, we perform 3D quantum dynamics (QD) and full-dimensional trajectory surface hopping (TSH, in conjunction with a linear vibronic coupling model), with the modes for QD selected by TSH. We follow a hybrid approach which is based on the application of time-dependent density functional theory (TD-DFT) excited-state potential energy surfaces (PESs) and multiconfigurational second-order perturbation theory (CASPT2) spin-orbit couplings (SOCs). Our method delivers accurate singlet-triplet-quintet intersystem crossing (ISC) dynamics, as assessed by comparison to our recent high-level ab initio simulations and related time-resolved experimental data. Furthermore, we investigate the capability of our simulations to identify the location of ISCs. Finally, we assess the approximation of constant SOCs (calculated at the Franck-Condon geometry), whose validity has central importance for the combination of TD-DFT PESs and CASPT2 SOCs. This efficient methodology will have a key role in simulating LS → HS dynamics for more complicated cases, involving higher density of states and varying electronic character, as well as the analysis of ultrafast experiments.

Pluripotent pancreatic stellate cells (PSCs) receive growing interest in past decades. Two types of PSCs are recognized -vitamin A accumulating quiescent PSCs and activated PSCs- the main producents of extracellular matrix in pancreatic tissue. PSCs plays important role in pathogenesis of pancreatic fibrosis in pancreatic cancer and chronic pancreatitis. PSCs are intensively studied as potential therapeutical target because of their important role in developing desmoplastic stroma in pancreatic cancer. There also exists evidence that PSC are involved in other pathologies like type-2 diabetes mellitus. This article brings brief characteristics of PSCs and recent advances in research of these cells.

The enantioselective kinetic resolution of β-unfunctionalized primary alcohols with benzoyl chloride was carried out in the presence of a catalytic amount of a novel chiral 1,2-diamine derived from (S)-proline. Several valuable chiral 2-substituted propan-1-ols were obtained with good enantioselectivities. Density functional theory calculations revealed that the noncovalent interaction, such as CH-π interaction, is crucial for the enantioselectivity of the resolution. This study was conducted through an interplay between experiment and computation.

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Background: Lower survival rates for many cancer types correlate with changes in nuclear size/scaling in a tumor-type/tissue-specific manner. Hypothesizing that such changes might confer an advantage to tumor cells, we aimed at the identification of commercially available compounds to guide further mechanistic studies. We therefore screened for Food and Drug Administration (FDA)/European Medicines Agency (EMA)-approved compounds that reverse the direction of characteristic tumor nuclear size changes in PC3, HCT116, and H1299 cell lines reflecting, respectively, prostate adenocarcinoma, colonic adenocarcinoma, and small-cell squamous lung cancer. Results: We found distinct, largely nonoverlapping sets of compounds that rectify nuclear size changes for each tumor cell line. Several classes of compounds including, e.g., serotonin uptake inhibitors, cyclo-oxygenase inhibitors, β-adrenergic receptor agonists, and Na⁺/K⁺ ATPase inhibitors, displayed coherent nuclear size phenotypes focused on a particular cell line or across cell lines and treatment conditions. Several compounds from classes far afield from current chemotherapy regimens were also identified. Seven nuclear size-rectifying compounds selected for further investigation all inhibited cell migration and/or invasion. Conclusions: Our study provides (a) proof of concept that nuclear size might be a valuable target to reduce cell migration/invasion in cancer treatment and (b) the most thorough collection of tool compounds to date reversing nuclear size changes specific to individual cancer-type cell lines. Although these compounds still need to be tested in primary cancer cells, the cell line-specific nuclear size and migration/invasion responses to particular drug classes suggest that cancer type-specific nuclear size rectifiers may help reduce metastatic spread.

Microorganisms with extracellular electron transfer (EET) capability have gained significant attention for their different biotechnological applications, like biosensors, bioremediation, and microbial fuel cells. Current research affirmed that microbial EET potentially promotes corrosion of iron structures, termed microbiologically influenced corrosion (MIC). The sulfate-reducing (SRB) and nitrate-reducing (NRB) bacteria are the most investigated among the different MIC-promoting bacteria. Unlike extensively studied SRB corrosion, NRB corrosion has received less attention from researchers. Hence, this review focuses on EET by Pseudomonas aeruginosa, a pervasive bacterium competent for developing biofilms in marine habitats and oil pipelines. A comprehensive discussion on the fundamentals of EET mechanisms in MIC is provided first. After that, the review offers state-of-the-art insights into the latest research on the EET-assisted MIC by Pseudomonas aeruginosa. The role of electron transfer mediators has also been discussed to understand the mechanisms involved in a better way. This review will be beneficial to open up new opportunities for developing strategies for combating biocorrosion.

Keywords: Biofilm; Microbiologically induced corrosion; Nitrate reducing bacteria.

Tibetan turnip (Brassica rapa L.) polysaccharide (TTP) is an active ingredient and has been studied for many years due to its biological effect. There are a few studies on its digestion properties and the regulation of the intestinal microbiota. In this study, the regulation of intestinal health by TTP was investigated in vitro and in vivo. The results showed that TTP was not degraded after simulated gastrointestinal digestion. When TTP was fermented by the gut microbiota, the content of short-chain fatty acids (SCFAs) and the relative abundance of Bifidobacterium, Catenibacterium increased; the relative abundance of Prevotella, Phascolarctobacterium decreased. The in vivo experiments showed that TTP could reduce the abundances of Muribaculaceae and enrich Lactobacillus. The results of KEGG indicated that TTP could promote arginine and ornithine metabolism, fructose and mannose metabolism, and lipopolysaccharide biosynthesis. These data showed that TTP exerted its prebiotic effect by regulating the intestinal flora and could be used for preventing disease and improving health by maintaining intestinal health.

Cells and tissues are routinely cultured in vitro for biological research with findings being extrapolated to their host organ and tissue function. However, most samples are cultured and studied in unphysiological environments, without temporal variation in the biochemical cues that are ubiquitous in vivo. The artificiality of these conditions undermines the predictive value of cell culture studies. We ascribe the prevalence of this suboptimal culture methodology to the lack of practical continuous flow systems that are economical and robust. Here, we design and implement an expandable multiplexed flow system for cell culture superfusion. By expanding on the concept of the planar peristaltic pump, we fabricated a highly compact and multiplexed pump head with up to 48 active pump lines. The pump is incorporated into a custom, open-top superfusion system configured for conventional multi-well culture plates. We then demonstrated the utility of the system for in vitro circadian entrainment using a daily cortisol pulse, generating a sustained circadian amplitude that is essential for physiological emulation and chrono-pharmacological studies. The multiplexed pump is complemented by a package of fluidic interconnection and management methods enabling user-friendly and scalable operation. Collectively, the suite of technologies provides a much-needed improvement in physiological emulation to support the predictive value of in vitro biomedical and biological research.

The disproportionation of LiO₂ to Li₂O₂ is a key step in Li-O₂ batteries, and it is regarded as a second-order reaction. However, its mechanism is not well addressed, and its kinetics is rarely studied due to the difficulties of quantifying the rate constants, particularly for high concentrations of superoxide (>10 mM). Here, we quantified the kinetic rate constant by a microkinetic model using a microelectrode tip with a thin diffusion layer and fast response. We report that the reaction order of LiO₂ transitions from 1 at high concentrations of superoxide (∼20 mM) to 2 at low concentrations of superoxide (∼1 mM). LiO₂ is chemically reduced by free superoxides to form Li₂O₂ and O₂, instead of reacting with another LiO₂ via a disproportionation step. This chemical-reduction mechanism explained the change of reaction order and the kinetics profile. As a rate-determining step, this step restricts the overall kinetics of the discharging process and should be the focus of future catalyst design.

The tailored synthesis of graft copolymers from acrylic and methacrylic monomers can be accomplished solely through photoiniferter reversible addition-fragmentation chain transfer (RAFT) polymerization. Samples with poly[oligo(ethylene glycol) methacrylate] (POEGMA) backbones synthesized under green light irradiation and poly(N-isopropylacrylamide) (PNIPAM) side chains growing under blue light irradiation are presented. As monitored by temperature-dependent dynamic light scattering (DLS) measurements and temperature-variable nuclear magnetic resonance (NMR) spectroscopy, the architecture of the graft copolymers allows unique two-step lower critical solution temperature (LCST) transitions in aqueous solutions. Meanwhile, different end-groups introduced by the corresponding RAFT agents affect the detailed thermoresponsive behavior remarkably. This RAFT strategy shows more advantages when the multiple trithiocarbonate groups are converted into thiol reactive pyridyl disulfide (PDS) groups via a facile post-polymerization modification. The PDS-terminated graft copolymer can then be regarded as a usable precursor for various applications, such as thermoresponsive hydrogels.

The behavior of deoxyribonucleic acid (DNA) molecules in confinement is of profound importance in various bioengineering and medical applications. In the present study, all-atom molecular dynamics simulation is utilized to investigate the transition of the double-strand DNA (dsDNA) conformation in the electrolytic nanodroplet. Three typical conformations, i.e., C-shaped, folded S-shaped, and double C-shaped, are observed for different droplet sizes and ionic concentrations. To reveal the physics underlying this phenomenon, the characteristics of the dsDNA molecules, such as the overcharging intensity, the end-to-end distance, the radius of gyration, etc. are analyzed in detail based on the numerical results. It is found that the transition can be ascribed to the buckling of the polymer molecules under the compression due to the confinement of the nanodroplet, and it can be modulated by the ionic concentration in the electrolyte. Generally, nanoscale confinement dominates dsDNA behavior over the electrostatic effects in smaller nanodroplets, while the latter becomes more important for larger nanodroplets. This competition results in the persistence length increasing with the nanodroplet radii. Based on these discussions, a non-dimensional elasto-capillary number μ is proposed to classify the dsDNA conformations into three regions.

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Background: It is important to provide insight in potential target groups for interventions to reduce socioeconomic inequalities in children's vegetable/fruit consumption. In earlier studies often single indicators of socioeconomic status (SES) or migrant status have been used. However, SES is a multidimensional concept and different indicators may measure different SES dimensions. Our objective is to explore multiple associations of SES indicators and migrant status with risk of a low vegetable/fruit consumption in a large multi-ethnic and socioeconomically diverse sample of children.

Methods: We included 5,010 parents of 4- to 12-year-olds from a Dutch public health survey administered in 2018. Cross-sectional associations of parental education, material deprivation, perceived financial difficulties, neighbourhood socioeconomic status (NSES) and migrant status with low (≤4 days a week) vegetable and fruit consumption in children were assessed using multilevel multivariable logistic regression models. Results are displayed as odds ratios (OR) with 95% confidence intervals (CI).

Results: Of the 4- to 12-year-olds, 22.1% had a low vegetable consumption and 11.9% a low fruit consumption. Low (OR 2.51; 95%CI: 2.05, 3.07) and intermediate (OR 1.83; 95%CI: 1.54, 2.17) parental education, material deprivation (OR 1.45; 95%CI: 1.19, 1.76), low NSES (OR 1.28; 95%CI: 1.04, 1.58) and a non-Western migrant status (OR 1.94; 95%CI: 1.66, 2.26) were associated with a higher risk of a low vegetable consumption. Low (OR 1.68; 95%CI: 1.31, 2.17) and intermediate (OR 1.39; 95%CI: 1.12, 1.72) parental education and material deprivation (OR 1.63; 95%CI: 11.27, 2.08) were also associated with a higher risk of a low fruit consumption.

Conclusion: Our findings indicate associations of multiple SES indicators and migrant status with a higher risk of a low vegetable/fruit consumption in children and thus help to identify potential target groups.

Keywords: CI, Confidence interval; Child; Food consumption; Fruit; IQR, Interquartile range; MOR, Median odds ratio; NSES, Neighbourhood socioeconomic status; Netherlands; OR, Odds ratio; SES, Socioeconomic Status; Socioeconomic status; VIF, Variance inflation factor; Vegetables.

Background: Excessive inflammatory activities are reported to be the primary cause of sepsis-induced acute kidney injury (AKI). Ras guanyl nucleotide-releasing protein (RasGRP) could prevent inflammatory response. However, its role in the regulation of inflammatory response in sepsis-associated AKI remains unclear.

Methods: Wild-type or RasGRP1-deficient mice were treated with lipopolysaccharide intraperitoneally in combination with D-galactosamine to establish a mouse model of sepsis-associated AKI. Serum inflammatory cytokines were measured using enzyme-linked immunosorbent assay. The messenger RNA (mRNA) levels of interleukin 6, tumor necrosis factor, nitric oxide synthase 2, and interleukin 1β were measured using quantitative reverse-transcription polymerase chain reaction. The morphological change in kidney tubule was determined by hematoxylin-and-eosin staining. The protein levels of RasGRP, extracellular signal-regulated kinases 1 and 2 (ERK1/2), and c-Jun N-terminal kinase (JNK) were determined using Western blot.

Results: RasGRP1 mRNA and protein levels were significantly increased in patients with sepsis-related AKI compared to those in healthy subjects. RasGRP knockout markedly reduced inflammatory cytokines induced by AKI in sepsis when compared with wild-type mice. Additionally, RasGRP deficiency inhibited the phosphorylation of ERK1/2 without altering JNK expression. In conclusion, we demonstrate that RasGRP1 plays a pivotal role in sepsis-associated AKI. Downregulation of RasGRP1 could significantly inhibit inflammatory response by inhibiting the activation of ERK1/2 and mitogen-activated protein kinase pathway, thereby reducing AKI induced by sepsis.

Conclusions: Our data suggest that RasGRP exacerbates lipopolysaccharide-induced acute kidney injury through regulating ERK activation, which reveals a potential therapeutic target for the treatment of sepsis-induced AKI.

Keywords: ERK/MAPK pathway; RasGRP; acute kidney injury; inflammation; sepsis.