Supramolecular polymers form tactoids through liquid-liquid phase separation.

Liquid-liquid phase separation (LLPS) of biopolymers has recently been shown to play a central role in the formation of membraneless organelles with a multitude of biological functions1-3. The interplay between LLPS and macromolecular condensation is part of continuing studies4,5. Synthetic supramolecular polymers are the non-covalent equivalent of macromolecules but they are not reported to undergo LLPS yet. Here we show that continuously growing fibrils, obtained from supramolecular polymerizations of synthetic components, are responsible for phase separation into highly anisotropic aqueous liquid droplets (tactoids) by means of an entropy-driven pathway. The crowding environment, regulated by dextran concentration, affects not only the kinetics of supramolecular polymerizations but also the properties of LLPS, including phase-separation kinetics, morphology, internal order, fluidity and mechanical properties of the final tactoids. In addition, substrate-liquid and liquid-liquid interfaces proved capable of accelerating LLPS of supramolecular polymers, allowing the generation of a myriad of three-dimensional-ordered structures, including highly ordered arrays of micrometre-long tactoids at surfaces. The generality and many possibilities of supramolecular polymerizations to control emerging morphologies are demonstrated with several supramolecular polymers, opening up a new field of matter ranging from highly structured aqueous solutions by means of stabilized LLPS to nanoscopic soft matter.

Genetic diversity, biofilm formation, and Vancomycin resistance of clinical Clostridium innocuum isolates.

BACKGROUND: Clostridium innocuum, previously considered a commensal microbe, is a spore-forming anaerobic bacterium. C. innocuum displays inherent resistance to vancomycin and is associated with extra-intestinal infections, antibiotic-associated diarrhea, and inflammatory bowel disease. This study seeks to establish a multilocus sequence typing (MLST) scheme to explore the correlation between C. innocuum genotyping and its potential pathogenic phenotypes. METHODS: Fifty-two C. innocuum isolates from Linkou Chang Gung Memorial Hospital (CGMH) in Taiwan and 60 sequence-available C. innocuum isolates from the National Center for Biotechnolgy Information Genome Database were included. The concentrated sequence of housekeeping genes in C. innocuum was determined by amplicon sequencing and used for MLST and phylogenetic analyses. The biofilm production activity of the C. innocuum isolates was determined by crystal violet staining. RESULTS: Of the 112 C. innocuum isolates, 58 sequence types were identified. Maximum likelihood estimation categorized 52 CGMH isolates into two phylogenetic clades. These isolates were found to be biofilm producers, with isolates in clade I exhibiting significantly higher biofilm production than isolates in clade II. The sub-inhibitory concentration of vancomycin seemed to minimally influence biofilm production by C. innocuum isolates. Nevertheless, C. innocuum embedded in the biofilm structure demonstrated resistance to vancomycin treatments at a concentration greater than 256 µg/mL. CONCLUSIONS: This study suggests that a specific genetic clade of C. innocuum produces a substantial amount of biofilm. Furthermore, this phenotype assists C. innocuum in resisting high concentrations of vancomycin, which may potentially play undefined roles in C. innocuum pathogenesis.

Gut Microbiomics of Sustained Knee Pain in Knee Osteoarthritis Patients.

OBJECTIVE: To examine whether gut microbes were associated with post-surgery sustained knee pain in knee osteoarthritis (OA) patients by a gut microbiomics approach. METHODS: Total knee replacement (TKR) patients due to primary knee OA were recruited. Sustained knee pain status at least one year after TKR was defined by the Western Ontario and McMaster University Arthritis Index (WOMAC). Fasting plasma sample and fecal sample were collected. Metabolomic profiling was performed on fasting plasma. 16S rRNA sequencing was performed on fecal samples to determine microbial composition. RESULTS: Twenty TKR patients due to primary knee OA were included in the study with 10 experiencing sustained post-surgery pain and 10 without such pain. Age, sex, and BMI were matched. Linear discriminant analysis of microbiome data identified 13 bacterial taxa that were highly abundant in the pain group, and 5 that were highly abundant in the non-pain group (all P < 0.05). Plasma metabolomic profiling measured 622 metabolites. The correlation analysis indicated that the 18 taxa were significantly correlated with 231 metabolites (all P < 0.05). sPLS-DA analysis showed that 30 out of the 231 metabolites explained 29% of total variance and can be used to clearly separate sustained knee pain patients from non-pain patients. Pathway enrichment analysis showed that these significant metabolites were enriched in arachidonic acid metabolic pathway, bile acid biosynthesis, and linoleic acid metabolism. CONCLUSION: The gut microbes may play a significant role in sustained knee pain in knee OA patients after TKR potentially through their activation of inflammatory pathways, lipid metabolism, and central sensitization.

Comparative Spatial Modeling of Bretziella fagacearum Distribution in Northern Wisconsin, United States.

Bretziella fagacearum, the ascomycete fungus oak wilt, is considered a virulent threat to North American oaks, but the influence of the physical environment on this pathosystem remains unclear, particularly at the forest scale. This study explored the influence of terrain and soil factors on B. fagacearum infections, applying discrete and continuous spatial models to investigate the question, besides proximity to other infections, which environmental factors influenced B. fagacearum incidence? Locations of infections were recorded from 586 confirmed B. fagacearum sites, identified from 2004 through 2021 in a 76 km2 area of deep, sandy glacial outwash in Chequamegon-Nicolet National Forest, northern Wisconsin. Public datasets derived from remote sensing were incorporated as covariates, describing terrain elevation (USGS 10-m DEM), soil physical and chemical properties (POLARIS), and forest composition (WiscLand2). Spatial models included generalized additive models (GAMs) and Neyman-Scott cluster process models. The results indicated that spatial dependence and the distribution of oak forests were the most important drivers of B. fagacearum distribution in this area, with more minor influence from elevation, hill shade, and drainage patterns. Comparison between modeling approaches indicated that-at this scale and in this area-the most accurate models were those that included host distribution, spatial dependence, and quantitative terrain and soil descriptions. However, a close approximation could be attained using nonlinear models (GAMs) that incorporated only host distribution and spatial dependence.

CRISPR screening reveals gleason score and castration resistance related oncodriver ring finger protein 19 A (RNF19A) in prostate cancer.

Prostate cancer (PCa) is one of the most lethal causes of cancer-related death in male. It is characterized by chromosomal instability and disturbed signaling transduction. E3 ubiquitin ligases are well-recognized as mediators leading to genomic alterations and malignant phenotypes. There is a lack of systematic study on novel oncodrivers with genomic and clinical significance in PCa. In this study we used clustered regularly interspaced short palindromic repeats (CRISPR) system to screen 656 E3 ubiquitin ligases as oncodrivers or tumor repressors in PCa cells. We identified 51 significantly changed genes, and conducted genomic and clinical analysis on these genes. It was found that the Ring Finger Protein 19 A (RNF19A) was a novel oncodriver in PCa. RNF19A was frequently amplified and highly expressed in PCa and other cancer types. Clinically, higher RNF19A expression correlated with advanced Gleason Score and predicted castration resistance. Mechanistically, transcriptomics, quantitative and ubiquitination proteomic analysis showed that RNF19A ubiquitylated Thyroid Hormone Receptor Interactor 13 (TRIP13) and was transcriptionally activated by androgen receptor (AR) and Hypoxia Inducible Factor 1 Subunit Alpha (HIF1A). This study uncovers the genomic and clinical significance of a oncodriver RNF19A in PCa. The results of this study indicate that targeting AR/HIF1A-RNF19A-TRIP13 signaling axis could be an alternative option for PCa diagnosis and therapy.

Fuzheng Huayu recipe inhibits bleomycin-induced pulmonary fibrosis in rats by inhibiting M2 polarization of macrophages via the oxidative phosphorylation pathway.

Fuzheng Huayu recipe (FZHYR) is a Chinese patent medicine for the treatment of fibrosis. The effects of FZHYR on pulmonary fibrosis and macrophage polarization were investigated in vitro. FZHYR inhibited pulmonary inflammation and fibrosis and M2 polarization of macrophages in bleomycin-induced pulmonary fibrosis (BPF) of rat model. Differentially expressed genes were screened by high-throughput mRNA sequencing and GSEA showed that oxidative phosphorylation (OXPHOS) was correlated with BPF. FZHYR inhibited expressions of Ndufa2 and Ndufa6 in lung tissues of BPF rats. These findings suggest that OXPHOS pathway serves as a possible target for pulmonary fibrosis therapy by FZHYR.

Peer Bullying Victimization Trajectories for Sexually and Gender Diverse Youth from Early Childhood to Late Adolescence.

Sexually and gender diverse (SGD) youth experience more peer bullying victimization than heterosexual, cisgender youth during adolescence, yet the emergence and persistence of these disparities remain underexplored. Also, it is unclear which factors are associated with these disparities across development, and how these disparities are linked to late adolescent health discrepancies. This study utilized the sample from the Millennium Cohort Study in Britain (N = 10,080; 51.3% assigned female at birth; Mage = 2.28, SDage = 0.46 at Wave 2), in which 23.74% of youth reported non-heterosexual attraction, 21.59% reported non-heterosexual identity, and 1.08% reported gender identity not in line with the sex assigned at birth. Using latent class growth modeling, four peer bullying victimization trajectories were identified, with early peak (7.2%), late childhood peak (6.3%), adolescence onset (12.8%), and low (73.6%) rates of victimization. SGD youth, compared to heterosexual and cisgender youth, were found to have increased odds of being in the victimization-involved classes, especially the adolescence onset class. The study further revealed that SGD youth reported more mental health and relational difficulties in childhood, which were linked to their heightened risk of longer-lasting victimization. Further, long-term victimization was found to partially account for the disparities in health and well-being for SGD youth in late adolescence. In conclusion, SGD youth were more likely to experience longer-lasting bullying victimization during childhood and adolescence, its related mental and relational vulnerabilities were already established in childhood, and such victimization disparities were further linked to their detrimental health and well-being in late adolescence. The design, hypotheses, and target analyses of the current study were preregistered on 21st April 2023 at https://osf.io/f2zxy .

Application of European-specific polygenic risk scores for predicting prostate cancer risk in different ancestry populations.

BACKGROUND: Polygenic risk score (PRS) has shown promise in predicting prostate cancer (PCa) risk. However, the application of PRS in non-European ancestry was poorly studied. METHODS: We constructed PRS using 68, 86, or 128 PCa-associated single-nucleotide polymorphisms (SNPs) identified through a large-scale Genome-wide association study (GWAS) in the European ancestry population. A calibration approach was performed to adjust the PRS exact value for each ancestry. The study was conducted in East Asian (ChinaPCa Consortium, n = 2379), European (UK Biobank, n = 209,172), and African American (African Ancestry Prostate Cancer Consortium, n = 6016). RESULTS: Individuals with the highest PRS (in >97.5th percentile) had over 2.5-fold increased risk of PCa than those with average PRS (in 40th-60th percentile) in both European (odds ratio [OR] = 3.79, 95% confidence interval [CI] = 3.46-4.16, p < 0.001) and Chinese (OR = 2.87, 95% CI = 1.29-6.40, p = 0.010), while slightly lower in African American (OR = 1.77, 95% CI = 1.22-2.58, p = 0.008). Compared with the lowest PRS (in <2.5th percentile), increased PRS was also associated with the earlier onset of PCa (All log-rank p < 0.05). The highest PRS contributed to having about 5- to 12-fold higher lifetime risk and 5-10 years earlier at disease onset than the lowest category across different ancestry populations. CONCLUSION: We demonstrated that European-GWAS-based PRS could also significantly predict PCa risk in Asian ancestry and African ancestry populations.

Genetic risk assessment of lethal prostate cancer using polygenic risk score and hereditary cancer susceptibility genes.

BACKGROUND: The genetic risk of aggressive prostate cancer (PCa) is hard to be assessed due to the lack of aggressiveness-related single-nucleotide polymorphisms (SNPs). Prostate volume (PV) is a potential well-established risk factor for aggressive PCa, we hypothesize that polygenic risk score (PRS) based on benign prostate hyperplasia (BPH) or PV-related SNPs may also predict the risk of aggressive PCa or PCa death. METHODS: We evaluated a PRS using 21 BPH/PV-associated SNPs, two established PCa risk-related PRS and 10 guideline-recommended hereditary cancer risk genes in the population-based UK Biobank cohort (N = 209,502). RESULTS: The BPH/PV PRS was significantly inversely associated with the incidence of lethal PCa as well as the natural progress in PCa patients (hazard ratio, HR = 0.92, 95% confidence interval [CI]: 0.87-0.98, P = 0.02; HR = 0.92, 95% CI 0.86-0.98, P = 0.01). Compared with men at the top 25th PRS, PCa patients with bottom 25th PRS would have a 1.41-fold (HR, 95% CI 1.16-1.69, P = 0.001) increased PCa fatal risk and shorter survival time at 0.37 yr (95% CI 0.14-0.61, P = 0.002). In addition, patients with BRCA2 or PALB2 pathogenic mutations would also have a high risk of PCa death (HR = 3.90, 95% CI 2.34-6.51, P = 1.79 × 10-7; HR = 4.29, 95% CI 1.36-13.50, P = 0.01, respectively). However, no interactive but independent effects were detected between this PRS and pathogenic mutations. CONCLUSIONS: Our findings provide a new measurement of PCa patients' natural disease outcomes via genetic risk ways.

Osteoarthritis year in review 2023: metabolite and protein biomarkers.

OBJECTIVE: To highlight the advances over the past year in metabolite/protein biomarkers for osteoarthritis (OA). METHOD: A literature search of five databases including PubMed, Web of Science, Scopus, Ovid Medline, and Embase was performed for studies on metabolite/protein/peptide/biochemical markers for OA published between April 1st, 2022 and March 31st, 2023. Records were then screened to include only original research articles using directly collected human specimens, in English language, and with full text available. Data from eligible studies were systematically extracted and summarized. RESULTS: A total of 1600 unique records were extracted, out of which 46 fulfilled the inclusion criteria and were used for data extraction. Forty-one of these 46 studies focused on biomarkers for OA/OA severity/progression, four on OA clustering, and one on OA treatment outcomes. Twenty-nine studied protein markers for OA, thirteen studied metabolite markers, and four studied both. While many studies were the validation of the previously reported biomarkers, a number of novel metabolite/protein biomarkers and biomarker panels were reported in the past year. Biomarker panels might be useful to subset OA patients. CONCLUSION: The number of studies on OA clustering is rising. Although validation in larger cohorts is needed in order to utilize reported biomarkers in clinical practice, these discoveries help better understand the pathogenesis of OA, provide insights into possible mechanisms underlying poor treatment outcomes, and aid in developing personalized treatment based on OA subtypes.

Association of serum copper (Cu) with cardiovascular mortality and all-cause mortality in a general population: a prospective cohort study.

BACKGROUND: Copper (Cu) homeostasis and Cu-induced cell death are gaining recognition as crucial processes in the pathogenesis of cardiovascular disease (CVD). Circulating Cu associated with CVD and mortality is yet to be fully elucidated. OBJECTIVE: This national prospective cohort study is to estimate relationship between serum Cu and the risk of CVD and all-cause mortality. METHODS: This study included participants from the National Health and Nutrition Examination Survey 2011-2016. Weighted Cox proportional hazards regression analysis and exposure-response curves were applied. RESULTS: This included 5,412 adults, representing 76,479,702 individuals. During a mean of 5.85 years of follow-up (31,653 person-years), 96 CVD and 356 all-cause mortality events occurred. Age and sex-adjusted survival curves showed that individuals with higher levels of serum Cu experienced increased CVD and all-cause death rates (tertiles, p < 0.05). Compared with the participant in tertile 1 of serum Cu (< 16.31 mol/L), those in tertile 3 (≥ 19.84 mol/L) were significantly associated with CVD mortality (HR: 7.06, 95%CI: 1.85,26.96), and all-cause mortality (HR: 2.84, 95% CI: 1.66,4.87). The dose-response curve indicated a linear relationship between serum Cu and CVD mortality (p -nonlinear = 0.48) and all-cause (p -nonlinear = 0.62). A meta-analysis included additional three prospective cohorts with 13,189 patients confirmed the association between higher serum Cu and CVD (HR: 2.08, 95% CI: 1.63,2.65) and all-cause mortality (HR: 1.89, 95%CI: 1.58,2.25). CONCLUSION: The present study suggests excessive serum Cu concentrations are associated with the risk of CVD and all-cause mortality in American adults. Our findings and the causal relationships require further investigation.

Profiles and Transitions of Cyberbullying Perpetration and Victimization from Childhood to Early Adolescence: Multi-Contextual Risk and Protective Factors.

Cyberbullying may negatively affect youth's development. Because knowledge of the onset and course of cyberbullying during middle childhood and early adolescence is limited, studies of its antecedents, heterogeneous profiles, and transitions are needed to inform prevention and intervention efforts. The current longitudinal study explored the profiles and transitions of cyberbullying perpetration and victimization from middle childhood to early adolescence, along with their multi-contextual risk and protective factors. A total of 4326 Chinese elementary school students (44.6% female, Mage = 9.94) participated in self-report assessments at four time points with six-month intervals. The profiles and transitions of cyberbullying were modeled using latent profile analysis and latent transition analysis. Three cyberbullying profiles were identified: non-involved, cyberbully-victims, and cybervictims. The findings on the development of cyberbullying showed that: (1) its prevalence rate decreased from middle to late childhood and then increased during the transition to early adolescence; and (2) its stability increased from middle childhood to early adolescence. Multi-contextual risk and protective factors of profile memberships and transitions were also examined. The findings suggested that: (1) family abuse and peer aggression were stable risk factors for cyberbully-victims; (2) high-quality friendships and self-control were stable protective factors for cyberbully-victims; (3) family abuse and depressive symptoms were stable risk factors for cybervictims; and (4) significant predictive effects of family abuse, high-quality friendships, perceived parental warmth, and self-control were found for the transitions in cyberbullying profiles. These results supported multi-contextual models of the development and transitions of cyberbullying in Chinese children.

Flow cytometry and 5-ethynyl-2'-deoxyuridine (EdU) labeling to detect the cell cycle dynamics of Phaeodactylum tricornutum under light.

Cell cycle studies in plants and algae are highly dependent on reliable methods for detecting cellular DNA replication. With its short growth cycle and ease of genetic transformation, Phaeodactylum tricornutum is an important model organism for the study of pennate diatoms. Here we explored two different methods to detect the cell cycle of P. tricornutum, one using SYBR-green I to via flow cytometry, and the other using EdU labeling to observe cell cycle changes under fluorescence microscopy. Both EdU labeling fluorescence microscopy and SYBR-green I staining flow cytometry accurately indicated that the cells of P. tricornutum enter the G2/M phase after 12 h of light exposure. The results indicate that SYBR Green I was an adequate detection method for nuclear DNA quantitation in cells of P. tricornutum using a flow cytometer and without RNase A treatment. In addition, EdU can be applied to P. tricornutum to reliably detect cell proliferation. Besides, Mg-ProtoIX was able to reverse the cell cycle division inhibition of P. tricornutum and allow the nuclear DNA replication to proceed normally. Taken together, the photoperiodic division time point was clearly identified, which sheds light on the regulation of cell division mechanism in P. tricornutum.

Genetic polymorphisms at 19q13.33 are associated with [-2]proPSA (p2PSA) levels and provide additional predictive value to prostate health index for prostate cancer.

BACKGROUND: Prostate health index (phi), a derivative of [-2]proPSA (p2PSA), has shown better accuracy than prostate-specific antigen (PSA) in prostate cancer (PCa) detection. The present study was to investigate whether previously identified PSA-associated single nucleotide polymorphisms (SNPs) influence p2PSA or phi levels and lead to potential clinical utility. METHODS: We conducted an observational prospective study with 2268 consecutive patients who underwent prostate biopsy in three tertiary medical centers from August 2013 to March 2019. Genotyping data of the 46 candidate genes with a ± 100 kb window were tested for association with p2PSA and phi levels using linear regression. Multivariable logistic regression models were performed and internally validated using repeated tenfold cross-validation. We further calculated personalized phi cutoff values based on the significant genotypes. Discriminative performance was assessed using decision curve analysis and net reclassification improvement (NRI) index. RESULTS: We detected 11 significant variants at 19q13.33 which were p2PSA-associated independent of PCa. The most significant SNP, rs198978 in KLK2 (Pcombined = 5.73 × 10-9 ), was also associated with phi values (Pcombined = 3.20 × 10-6 ). Compared to the two commonly used phi cutoffs of 27.0 and 36.0, the personalized phi cutoffs had a significant NRI for PCa ranged from 5.23% to 9.70% among men carrying variant types (all p < .01). CONCLUSION: Rs198978, is independently associated with p2PSA values, and can improve the diagnostic ability of phi for PCa using personalized cutoff values.

Nitrates and risk of vasovagal reaction in femoral sheath removal after percutaneous intervention : A retrospective observational study.

BACKGROUND: The aim of this study was to analyze the risk factors for vasovagal reaction (VVR) in manual femoral sheath removal after percutaneous coronary intervention and to discuss methods for the prevention and control of VVR. METHODS: The data of 455 patients who underwent percutaneous intervention in four interventional centers during a period of 30 months were retrospectively analyzed. Patients were divided into a VVR group and a control group according to whether VVR developed. The clinical data of all patients were analyzed using univariate and multivariate logistic regression analysis to examine VVR -related factors. RESULTS: A total of 455 patients underwent 464 manual femoral sheath removal operations, of whom 12 developed VVR (2.59%). Of these 12 VVR patients, one had VVR during and 11 had VVR after the intervention. There were no statistically significant differences between the two groups in age, body mass index, gender, time of sheath removal, proportions of patients with hypertension, diabetes, and hyperlipemia, laboratory values of hemoglobin a1c, and ejection fraction (p > 0.05). Compared with the control group, use of nitrates was the only risk factor with a significant correlation with VVR (p = 0.012). CONCLUSION: In manual femoral sheath removal, the use of nitrates is the most important risk factor for the occurrence of VVR after percutaneous intervention.

Urolithin A attenuates memory impairment and neuroinflammation in APP/PS1 mice.

BACKGROUND: Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by an abnormal accumulation of amyloid-ß (Aß) plaques, neuroinflammation, and impaired neurogenesis. Urolithin A (UA), a gut-microbial metabolite of ellagic acid, has been reported to exert anti-inflammatory effects in the brain. However, it is unknown whether UA exerts its properties of anti-inflammation and neuronal protection in the APPswe/PS1ΔE9 (APP/PS1) mouse model of AD. METHODS: Morris water maze was used to detect the cognitive function. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay was performed to detect neuronal apoptosis. Immunohistochemistry analyzed the response of glia, Aß deposition, and neurogenesis. The expression of inflammatory mediators were measured by enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qRT-PCR). The modulating effects of UA on cell signaling pathways were assayed by Western blotting. RESULTS: We demonstrated that UA ameliorated cognitive impairment, prevented neuronal apoptosis, and enhanced neurogenesis in APP/PS1 mice. Furthermore, UA attenuated Aß deposition and peri-plaque microgliosis and astrocytosis in the cortex and hippocampus. We also found that UA affected critical cell signaling pathways, specifically by enhancing cerebral AMPK activation, decreasing the activation of P65NF-κB and P38MAPK, and suppressing Bace1 and APP degradation. CONCLUSIONS: Our results indicated that UA imparted cognitive protection by protecting neurons from death and triggering neurogenesis via anti-inflammatory signaling in APP/PS1 mice, suggesting that UA might be a promising therapeutic drug to treat AD.

JAK2/STAT3 signaling mediates IL-6-inhibited neurogenesis of neural stem cells through DNA demethylation/methylation.

Neuroinflammation, considered as a pathological hallmark of Alzheimer's disease (AD), has been demonstrated to affect hippocampal neurogenesis and cognitive function. Interleukin-6 (IL-6) is a proinflammatory cytokine known to modulate neurogenesis. However, the mechanisms are still largely unknown. Here, we reported that IL-6 suppressed neurogenesis via a JAK2/STAT3 signaling in neural stem cells (NSCs). Importantly, we found that NeuroD1 (Neurogenic differentiation 1) gene expression, which drives NSCs neurodifferentiation, was regulated by TET3 and DNMT1 in a JAK2/STAT3-dependent manner. We further found that JAK2/STAT3 inhibition enhanced demethylation of NeuroD1 regulatory elements in IL-6-treated cells, which is related to the significant upregulation of TET3 expression as well as the decreased expression of DNMT1. Furthermore, Inhibiting JAK2/STAT3 significantly rescued the memory deficits and hippocampal neurogenesis dysfunction in APP/PS1 mice. Our data suggest that JAK2/STAT3 signaling plays a vital role in suppressing neurogenesis of NSCs exposed to IL-6 at the epigenetic level, by regulating DNA methylation/demethylation.

On the impact of competing intra- and intermolecular triplet-state quenching on photobleaching and photoswitching kinetics of organic fluorophores.

While buffer cocktails remain the most commonly used method for photostabilization and photoswitching of fluorescent markers, intramolecular triplet-state quenchers emerge as an alternative strategy to impart fluorophores with 'self-healing' or even functional properties such as photoswitching. In this contribution, we evaluated combinations of both approaches and show that inter- and intramolecular triplet-state quenching processes compete with each other. We find that although the rate of triplet-state quenching is additive, the photostability is limited by the faster pathway. Often intramolecular processes dominate the photophysical situation for combinations of covalently-linked and solution-based photostabilizers and photoswitching agents. Furthermore we show that intramolecular photostabilizers can protect fluorophores from reversible off-switching events caused by solution-additives, which was previously misinterpreted as photobleaching. Our studies also provide practical guidance for usage of photostabilizer-dye conjugates for STORM-type super-resolution microscopy permitting the exploitation of their improved photophysics for increased spatio-temporal resolution. Finally, we provide evidence that the biochemical environment, e.g., proximity of aromatic amino-acids such as tryptophan, reduces the photostabilization efficiency of commonly used buffer cocktails. Not only have our results important implications for a deeper mechanistic understanding of self-healing dyes, but they will provide a general framework to select label positions for optimal and reproducible photostability or photoswitching kinetics in different biochemical environments.

Metformin treatment prevents amyloid plaque deposition and memory impairment in APP/PS1 mice.

Alzheimer'sdisease(AD) is characterized by deposition of amyloid-ß (Aß)plaques, neurofibrillary tangles, andneuronal loss, accompaniedbyneuroinflammation. Neuroinflammatoryprocesses are thought to contribute toAD pathophysiology. Metformin has been reported to have anti-inflammatory efficacy. However, whether metformin is responsible for the anti-neuroinflammationand neuroprotection on APPswe/PS1ΔE9 (APP/PS1) mice remains unclear. Here we showed that metformin attenuated spatial memory deficit, neuron loss in the hippocampus and enhanced neurogenesis in APP/PS1 mice. In addition, metformin administration decreased amyloid-ß (Aß)plaque load and chronic inflammation (activated microglia and astrocytes as well as pro-inflammatory mediators) in the hippocampus and cortex. Further study demonstrated that treatment with metformin enhanced cerebral AMPK activation. Meanwhile, metformin notably suppressed the activation of P65 NF-κB, mTOR and S6K, reduced Bace1 protein expression. Our data suggest that metformin can exert functional recovery of memory deficits and neuroprotective effect on APP/PS1 mice via triggering neurogenesis and anti-inflammation mediated by regulating AMPK/mTOR/S6K/Bace1 and AMPK/P65 NF-κB signaling pathways in the hippocampus, which may contribute to improvement in neurological deficits.

Simultaneous determination of eight bioactive components of Qishen Yiqi dripping pills in rat plasma using UFLC-MS/MS and its application to a pharmacokinetic study.

In this study, a rapid and reliable ultra-fast liquid chromatography-tandem mass spectrometry method was developed and validated for the simultaneous determination of eight active ingredients, including astragaloside IV, ononin, tanshinol, protocatechualdehyde, protocatechuic acid, salvianolic acid D, rosmarinic acid and ginsenoside Rg1 , in rat plasma. The plasma samples were pretreated by protein precipitation with acetonitrile. Chromatographic separation was performed on a Waters Acquity UPLC® BEH C18 column (1.7 µm particles, 2.1 × 100 mm). The mobile phase consisted of 0.1% aqueous formic acid (A)-acetonitrile with 0.1% formic acid (B) at a flow rate of 0.4 mL/min. Quantification was performed on a triple quadruple tandem mass spectrometry with electrospray ionization by multiple reaction monitoring both in the negative and in the positive ion mode. The lower limit of quantification of tanshinol was 2.0 ng/mL and the others were 5.0 ng/mL. The extraction recoveries, matrix effects, intra- and inter-day precision and accuracy of eight tested components were all within acceptable limits. The validated method was successfully applied to the pharmacokinetic study of the eight active constituents after intragastric administration of three doses (1.0, 3.0, 6.0 g/kg body weight) of Qishen Yiqi Dripping Pills to rats.