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  • Mckay Stack posted an update 1 month ago

    Leaching and transport of contaminants is a complex interacting system affected by a suite of environmental factors. This study demonstrates the potential significance of weather events and moisture movement when interpreting plutonium (Pu) migration and advective transport in the soil matrix. Using a column transport experiment, two soil types, a sandy soil and clay-rich soil, were spiked with 238Pu as a tracer to observe the effect of simulated tropical and arid rainfall events on Pu mobility. Partition coefficients (Kd) were determined over a period of weeks and under varying rainfall rates to establish the impact of changing weather events on Pu mobility. The variability of these temporal Kds covers six orders of magnitude over a relatively brief time period. This demonstrates the necessity for non-static Kds to accurately describe Pu transport in these systems. The Pu Kds determined by these column transport experiments fall within the bounds of anticipated values (approximately 80-300,000 mL g-1) from i in tropical sandy soil ecosystems.Composite materials have gained significant attention owing to the synergistic effects of their constituent materials, thereby facilitating their utilization in new applications or in improving the existing ones. In this study, a composite based on nickel phthalocyanine (NiTsPc), zinc oxide nanoparticles (ZnONPs), and carbon nanotubes (CNT) was developed and subsequently immobilized on a pyrolytic graphite electrode (PGE). The PGE/NiTsPc-ZnONPs-CNT was identified as a selective catalytic hybrid system for detection of neurotransmitter dopamine (DA). The electrochemical and morphological characterizations were conducted using atomic force microscopy (AFM). Chronoamperometry and differential pulse voltammetry (DPV) were used to detect DA and detection limits of 24 nM and 7.0 nM was found, respectively. In addition, the effects of some possible DA interferents, such as ascorbic acid, uric acid, and serotonin, on DA response were evaluated. Their presence did not show significant variations in the DA electrochemical response. The high specificity and sensitivity of PGE/NiTsPc-ZnONPs-CNT for DA enabled its direct detection in human serum without sample pretreatment as well as in DA-enriched serum samples, whose recovery levels were close to 100%, thereby confirming the effectiveness of the proposed method. In general, PGE/NiTsPc-ZnONPs-CNT is a promising candidate for future applications in clinical diagnosis.We report an early childhood onset Stiff Limb Syndrome (SLS) in association with unusual polyautoimmunity of GAD-65, anti-islet cell, and Thyroid Peroxidase (TPO) autoantibodies, who has achieved a nearly complete neurological recovery following combined immunotherapy, symptomatic and physical therapy. The patient had normal MRIs of the brain and spinal cord and a negative paraneoplastic work-up. Subsequently, she developed hypothyroidism requiring levothyroxine supplementation. We then conducted an extensive review of literature and identified 52 previously reported pediatric Stiff Man Syndrome (SMS)/Stiff Person Syndrome (SPS) or SLS cases, which has demonstrated a common association with other systemic autoimmune conditions. In the available literature, screening for concurrent autoimmunity has only been reported infrequently. We found that a paraneoplastic process is extremely rare in pediatric cases. Timely diagnosis and initiation of immunotherapy are critical to a favorable outcome. Therefore, we recommend to include SMS/SPS or SLS as an important differential diagnosis for MRI-negative myelopathy. Further clinical and research efforts should be focused on understanding the role of both genetic predisposition and environmental insults in the autoimmunity of pediatric SMS/SPS or SLS.Immune system dysfunction has been described in autism spectrum disorder. Here we tested the hypothesis that cerebellar defects are accompanied by immune dysfunction in adult mice lacking the autism-candidate gene Engrailed 2 (En2). Gene ontology analyses revealed that biological processes related to immune function were over-represented in the cerebellar transcriptome of En2-/- mice. Pro-inflammatory molecules and chemokines were reduced in the En2-/- cerebellum compared to controls. Conversely, pro-inflammatory molecules were increased in the peripheral blood of mutant mice. Our results suggest a link between immune dysfunction and cerebellar defects detected in En2-/- mice.A novel organomediated cleavage of benzoyl group using ethane-1,2-diamine and acetic acid under neutral condition enables an efficient synthesis of 1-(6-nitropyridin-2-yl)thiourea, which previously has been challenging to prepare by conventional methods. The successful synthesis of 1-(6-nitropyridin-2-yl)thiourea as a synthon permits development of a variety of 18F labeled heterocycles as PET imaging ligands such as N-(pyridin-2-yl)thiazol-2-amine derivatives. The utility of this synthon is demonstrated with the synthesis of a 18F-labeled PET tracer for studying prion disease. In vitro autoradiography using this PET tracer on sagittal rat brain slices showed highest accumulation of radioactivity in the hippocampus, cortex, and striatum, in accordance with reported immunostaining of PrPc in rat brain.Icariside II, a flavonol glycoside, one of the major components of Traditional Chinese Medicine Herba epimedii. In the present study, we found that Icariside II suppressed the proliferation of CRC by inducing cell cycle arrest and apoptosis in vitro and inhibited tumor growth in vivo. The further mechanism investigation showed that Icariside II suppressed the expression of β-catenin and led to the functional inactivation of Wnt/β-catenin signaling. Circβ-catenin was considered as a promising candidate for mediating the tumorigenesis and the activation of Wnt/β-catenin signaling in CRC cells. Furthermore, Icariside II has been proven to suppress the biogenesis of circβ-catenin via epigenetically targeting DNA methyltransferases (DNMTs) to decrease global DNA methylation levels in CRC cells. Taken together, our results indicated that Icariside II suppressed tumorigenesis by epigenetically silencing the activation of circβ-catenin-Wnt/β-catenin axis in colorectal cancer. More importantly, the information gained from this study suggest that Icariside II may have great potential to be developed as a therapeutic drug for CRC patients.Germacradienol is a main precursor in the biosynthesis of geosmin-type terpenes by a variety of microbes, but its biological activities are still unknown. In the biosynthetic mechanism study of an antifungal degraded sesquiterpenoid (1β,4β,4aβ,8aα)-4,8a-dimethyloctahydronaphthalene-1,4a(2H)-diol (5) with a geosmin scaffold, the germacradienol synthase B7C62_00490 was identified. To exploit the synthetic potential of the enzyme to create germacradienol, engineered strains were constructed by introducing key synthases of farnesyl diphosphate, germacradienol synthase B7C62_00490 and glycosyltransferase UGT73C5 in Escherichia coli BL21(DE3). Germacradienol (1) and the novel glycosylated derivate germacradienyl-11-O-β-d-glucopyranoside (3) were successfully obtained from engineered strains. The cytotoxic activity against nine human cancer cell lines and antimicrobial activities against a panel of bacteria and fungi of germacradienol analogs derived from engineered strains were evaluated. Germacradienol demonstrated multiple biological activities, including broad antimicrobial activities with MIC values ranging from 12.5 to 25.0 μg/mL and cytotoxic activities with IC50 values ranging from 21.0 to 83.5 μM. However, the glycosylated germacradienol was inactive.In a previous study, we reported that warming primary cultured cardiomyocytes to 38-42 °C puts the intracellular sarcomere into an oscillation state that repeatedly contracts and relaxes in a cycle close to the heartbeat. Interestingly, sarcomere during HSOs had contraction rhythm homeostasis that kept the oscillation cycle constant while changing the oscillation amplitude in response to changes in calcium concentration. We found in this study that sarcomere during HSOs chaotically fluctuates the oscillation amplitude. Sarcomere during HSOs flexibly changes the synchronization state, keeps the oscillation cycle constant, and changes the oscillation amplitude chaotically while changing in response to the change in calcium concentration. It is suggested that the dynamic synchronous state changes and chaotic properties between sarcomere contribute to the smooth change of the developmental tension of the sarcomere population, which depends on the cycle of calcium concentration change rather than the cycle of HSOs. This property is considered to be an important property for sarcomere, which contracts when the calcium concentration is high and then needs to be rapidly relaxed even if some calcium still remains.Plasmalogen localized in the raft of mammalian cell membranes plays a role in the storage of polyunsaturated fatty acid (PUFA), and exists to a higher extent in malignant cells that survive, and even grow in hypoxic conditions. The biosynthesis of plasmalogen in mammalian cells has been reported to depend on aerobic conditions. Using liquid chromatography-tandem mass spectrometry, we found that the intracellular concentration of plasmalogen species containing a PUFA at the sn-2-position did not change for two days from the start of hypoxic culture in human colorectal cancer-derived Caco2 cells. At the third day of hypoxia, Caco2 cells showed the average increase rate of 2.6 times in ethanolamine plasmalogen and 2.9 times in choline plasmalogen depending on the molecular species compared with those in the second day of hypoxia. In normoxic culture, there was little quantitative change in any species of both ethanolamine and choline plasmalogens for three days. The up-regulations of mRNA of Ca2+-independent phospholipase A2β and cytoplasmic phospholipase A2γ as well as the down-regulation of lysoplasmalogenase observed in hypoxia were suggested to be responsible for the increase of plasmalogen in Caco2 cells under hypoxia.The proliferation of sea lice (Lepeophtheirus salmonis) represents a major challenge for the salmonid aquaculture industry in Norway. CTP-656 Hydrogen peroxide (H2O2) is a chemotherapeutant frequently used on Norwegian farms, however, its toxicity to non-target benthic species and habitats remains poorly understood. Maerl beds are constructed by the accumulation of non-geniculate coralline algae and provide important ecological functions. Due to the rapid expansion of aquaculture in Norway and the continued use of H2O2 as an anti-sea lice treatment, it is crucial to understand the impact of H2O2 on the physiology of maerl-forming species. The effects of a 1 h exposure to H2O2 on the photophysiology and bleaching of the coralline alga Lithothamnion soriferum were examined here through a controlled time-course experiment. PAM fluorimetry measurements showed that H2O2 concentrations ≥ 200 mg l-1 negatively affected photosystem II (PSII) in thalli immediately after exposure, which was observed through a significant decline in maximum photochemical efficiency (Fv/Fm) and relative electron transport rate (rETR). The negative effects on PSII induced by oxidative stress, however, appear to be reversible, and full recovery of photosynthetic characteristics was observed 48 h to 28 days after exposure to 200 mg H2O2 l-1 and 2000 mg H2O2 l-1, respectively. At 28 days after exposure, there was evidence of two- to four-times more bleaching in thalli treated with concentrations ≥ 200 mg H2O2 l-1 compared to those in the control. This indicates that despite the recovery of PSII, persistent damages can occur on the structural integrity of thalli, which may considerably increase the vulnerability of coralline algae to further exposure to H2O2 and other chemical effluents from salmonid farms.