Orphan nuclear receptor Nurr1 induces neuron differentiation from embryonic cortical precursor cells via an extrinsic paracrine mechanism

AbstractNurr1 is an orphan nuclear receptor-type transcription factor (TF) that plays critical roles in midbrain dopamine neuron development. This study demonstrated a novel role for Nurr1 in neuronal/astrocytic differentiation of neural precursor (NP) cells isolated from rat embryonic cortices: overexpression of this TF promoted NP cell differentiation towards neurons at the expense of astrocytic differentiation. Single cell-based lineage analyses and experiments using co-cultures revealed that Nurr1 elicited its neurogenic role in an extrinsic paracrine manner. We defined diffusible factors and downstream neurogenic TFs responsible for the Nurr1-mediated neuronal differentiation

Early Union of Grafted Bone in Ankylosing Spondylitis: Comparative Study with Degenerative Spinal Disease

Patients with ankylosing spondylitis (AS) achieve early bone union compared to those with other spinal diseases. This study compared the time to bone union after surgery between AS patients and degenerative spinal disease patients. Patients with degenerative spinal diseases (control group) and AS (experimental group) underwent pedicle subtraction osteotomy followed by posterolateral fusion, and decompression and posterolateral fusion, respectively. There were 10 patients in the experimental group. The control group included 26 patients who were less than 50 years of age and underwent two-level autogenous grafting after decompression and spinal fusion. Autogenous grafts and a range of bone substitutes were used in the experimental group, whereas only autogenous grafts were used in the control group. Bone union was determined on the radiographs and 3-dimensional CT scan images. The level of union was assessed using the Lenke's and Christensen's classification systems. In the experimental group, the mean age was 41.3 years (range, 30 to 67 years), the mean follow-up period was 21.7 months (range, 12 to 43 months), and bone union was confirmed at an average of 3.5 months (range, 3 to 5 months) after surgery. In the control group, the mean age was 43.1 years (range, 35 to 50 years), the mean follow-up period was 21.8 months (range, 12 to 74 months), and bone union was observed at an average of 5.6 months (range, 4 to 12 months) after surgery. The difference in the time to bone union between the two groups was significant (p = 0.023). The union of grafted bone was obtained earlier in patients with AS than in those with degenerative spinal diseases. Therefore, future studies should examine the factors affecting the early union in AS patients

Electrical spin injection and accumulation in CoFe/MgO/Ge contacts at room temperature

We first report the all-electrical spin injection and detection in CoFe/MgO/moderately doped n-Ge contact at room temperature (RT), employing threeterminal Hanle measurements. A sizable spin signal of ~170 k{\Omega} {\mu}m^2 has been observed at RT, and the analysis using a single-step tunneling model gives a spin lifetime of ~120 ps and a spin diffusion length of ~683 nm in Ge. The observed spin signal shows asymmetric bias and temperature dependences which are strongly related to the asymmetry of the tunneling process.Comment: 28 pages, 5 figure

Investigating Endocrine Disrupting Impacts of Nine Disinfection Byproducts on Human and Zebrafish Estrogen Receptor Alpha

Background: Disinfection byproducts (DBPs) cause endocrine disruption via estrogenic or anti-estrogenic effects on estrogen receptors. However, most studies have focused on human systems, with little experimental data being presented on aquatic biota. This study aimed to compare the effects of nine DBPs on zebrafish and human estrogen receptor alpha (zERα and hERα). Methods: In vitro enzyme response-based tests, including cytotoxicity and reporter gene assays, were performed. Additionally, statistical analysis and molecular docking studies were employed to compare ERα responses. Results: Iodoacetic acid (IAA), chloroacetonitrile (CAN), and bromoacetonitrile (BAN) showed robust estrogenic activity on hERα (maximal induction ratios of 108.7%, 50.3%, and 54.7%, respectively), while IAA strongly inhibited the estrogenic activity induced by 17β-estradiol (E2) in zERα (59.8% induction at the maximum concentration). Chloroacetamide (CAM) and bromoacetamide (BAM) also showed robust anti-estrogen effects in zERα (48.1% and 50.8% induction at the maximum concentration, respectively). These dissimilar endocrine disruption patterns were thoroughly assessed using Pearson correlation and distance-based analyses. Clear differences between the estrogenic responses of the two ERαs were observed, whereas no pattern of anti-estrogenic activities could be established. Some DBPs strongly induced estrogenic endocrine disruption as agonists of hERα, while others inhibited estrogenic activity as antagonists of zERα. Principal coordinate analysis (PCoA) showed similar correlation coefficients for estrogenic and anti-estrogenic responses. Reproducible results were obtained from computational analysis and the reporter gene assay. Conclusions: Overall, the effects of DBPs on both human and zebrafish highlight the importance of controlling their differences in responsiveness for estrogenic activities including the water quality monitoring and endocrine disruption, as DBPs have species-specific ligand-receptor interactions.Peer reviewe

Assessment of Soil Washing for Simultaneous Removal of Heavy Metals and Low-Level Petroleum Hydrocarbons Using Various Washing Solutions

Bench-scale soil washing experiments were conducted for simultaneous removal of heavy metals (Pb, Cu, Zn) and low-level petroleum hydrocarbon contaminants from soils. Various washing solutions including hydrochloric acid (HCl), nitric acid (HNO3), sulfuric acid (H2SO4), tartaric acid (C4H6O6) and ethylenediaminetetraacetic acid (C10H16N2O8, EDTA) were used. The concentration of the washing solutions ranged from 0.1 to 3M with a liquid-to-solid ratio of 10. The soil washing results showed that hydrochloric acid (HCl) was the best washing solution at 3M for heavy metal removal. Other washing solutions also showed a significant removal of heavy metals, except for sulfuric acid (H2SO4). Sulfuric acid (H2SO4) exhibited the worst performance among all washing solutions used with respect to Pb removal. 1M HCl and HNO3were sufficient for effective Pb and Cu removal, and all of the tested washing solutions at a concentration of 0.1M produced results compliant with the Korean warning standard for Zn removal. In the case of total petroleum hydrocarbons (TPH), tartaric acid (C4H6O6) produced the highest removals at all concentration levels compared with other washing solutions. More specifically, TPH removal efficiencies exceeded 33 and 82 % at the lowest (0.1M) and highest (3M) tartaric acid (TA) concentrations, respectively. Overall, TA could be a viable washing solution for the removal of both heavy metals (Pb, Cu, Zn) and TPH from contaminated soils

Possible link between Arctic Sea ice and January PM10 concentrations in South Korea

In this study, we investigated the possible teleconnection between PM10 concentrations in South Korea and Arctic Sea ice concentrations at inter-annual time scales using observed PM10 data from South Korea, NCEP R2 data, and NOAA Sea Ice Concentration (SIC) data from 2001 to 2018. From the empirical orthogonal function (EOF) analysis, we found that the first mode (TC1) was a large-scale mode for PM10 in South Korea and explained about 27.4% of the total variability. Interestingly, the TC1 is more dominantly influenced by the horizontal ventilation effect than the vertical atmospheric stability effect. The pollution potential index (PPI), which is defined by the weighted average of the two ventilation effects, is highly correlated with the TC1 of PM10 at a correlation coefficient of 0.75, indicating that the PPI is a good measure for PM10 in South Korea at inter-annual time scales. Regression maps show that the decrease of SIC over the Barents Sea is significantly correlated with weakening of high pressure over the Ural mountain range region, the anomalous high pressure at 500 hPa over the Korean peninsula, and the weakening of the Siberian High and Aleutian low. Moreover, these patterns are similar to the correlation pattern with the PPI, suggesting that the variability of SIC over the Barents Sea may play an important role in modulating the variability of PM10 in South Korea through teleconnection from the Barents Sea to the Korean peninsula via Eurasia

Immobilization of Lead in Contaminated Firing Range Soil Using Biochar

Soybean stover-derived biochar was used to immobilize lead (Pb) in military firing range soil at a mass application rate of 0 to 20 wt.% and a curing period of 7 days. The toxicity characteristic leaching procedure (TCLP) was performed to evaluate the effectiveness of the treatment. The mechanism responsible for Pb immobilization in military firing range soil was evaluated by scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDX) and x-ray absorption fine structure (XAFS) spectroscopy analyses. The treatment results showed that TCLP Pb leachability decreased with increasing biochar content. A reduction of over 90 % in Pb leachability was achieved upon treatment with 20 wt.% soybean stover-derived biochar. SEM-EDX, elemental dot mapping and XAFS results in conjunction with TCLP leachability revealed that effective Pb immobilization was probably associated with the pozzolanic reaction products, chloropyromorphite and Pb-phosphate. The results of this study demonstrated that soybean stover-derived biochar was effective in immobilizing Pb in contaminated firing range soil