Because of its distinctive compositional properties and variability, low-speed ( 450 km s−1) solar wind is widely believed to originate from coronal streamers, unlike high-speed wind, which comes ...from coronal holes. An alternative scenario is that the bulk of the slow wind (excluding that in the immediate vicinity of the heliospheric current sheet) originates from rapidly diverging flux tubes rooted inside small coronal holes or just within the boundaries of large holes. This viewpoint is based largely on photospheric field extrapolations, which are subject to considerable uncertainties and do not include dynamical effects, making it difficult to be certain whether a source is located just inside or outside a hole boundary, or whether a high-latitude hole will be connected to Earth. To minimize the dependence on field-line extrapolations, we have searched for cases where equatorial coronal holes at central meridian are followed by low-speed streams at Earth. We describe 14 examples from the period 2014-2017, involving Fe xiv 21.1 nm coronal holes located near active regions and having equatorial widths of ∼3°-10°. The associated in situ wind was characterized by speeds v ∼ 300-450 km s−1 and by O7+/O6+ ratios of ∼0.05-0.15, with v showing the usual correlation with proton temperature. In addition, consistent with other recent studies, this slow wind had remarkably high Alfvénicity, similar to that in high-speed streams. We conclude that small coronal holes are a major contributor to the slow solar wind during the maximum and early post-maximum phases of the solar cycle.
Summary
Background
Studies on the relation between alcohol consumption and risk of colorectal adenoma (CRA), a precursor of colorectal cancer, have been inconsistent.
Aim
A systematic review with ...meta‐analysis was conducted to investigate the association and the dose–response of alcohol with CRA.
Methods
A literature search was performed on PubMed to identify relevant studies published up to January 2014. A fixed or random effects model was used to estimate summarised relative risks (RRs) and 95% confidence intervals (CIs) for the association between alcohol intake and CRA risk. Statistical heterogeneity between studies was assessed with the χ2 statistic and quantified by I².
Results
Twenty‐three case–control studies and two cohort studies were included in the meta‐analysis. All drinkers were associated with 17% increased risk for CRA, compared with nondrinkers or occasional alcohol drinkers. The dose–response analysis demonstrated that for drinkers of 10, 25, 50 and 100 g/day alcohol consumption, the estimated RRs of CRA were 1.02 (95% CI 0.89–1.16), 1.06 (95% CI 0.92–1.20), 1.16 (95% CI 1.02–1.33) and 1.61 (95% CI 1.42–1.84) respectively, in comparison with non‐/occasional drinkers. The risks were consistent in the subgroup analyses of gender and site of adenoma, while it was stronger in European studies than the studies in the US and Asia.
Conclusions
This study suggests that alcohol intake is related to a significant increase of risk for colrectal adenoma.
meso-Galactaric acid is a dicarboxylic acid that can be produced by the oxidation of D-galacturonic acid, the main constituent of pectin. Mould strains can be engineered to perform this oxidation by ...expressing the bacterial enzyme uronate dehydrogenase. In addition, the endogenous pathway for D-galacturonic acid catabolism has to be inactivated. The filamentous fungus Aspergillus niger would be a suitable strain for galactaric acid production since it is efficient in pectin hydrolysis, however, it is catabolizing the resulting galactaric acid via an unknown catabolic pathway.
In this study, a transcriptomics approach was used to identify genes involved in galactaric acid catabolism. Several genes were deleted using CRISPR/Cas9 together with in vitro synthesized sgRNA. As a result, galactaric acid catabolism was disrupted. An engineered A. niger strain combining the disrupted galactaric and D-galacturonic acid catabolism with an expression of a heterologous uronate dehydrogenase produced galactaric acid from D-galacturonic acid. The resulting strain was also converting pectin-rich biomass to galactaric acid in a consolidated bioprocess.
In the present study, we demonstrated the use of CRISPR/Cas9 mediated gene deletion technology in A. niger in an metabolic engineering application. As a result, a strain for the efficient production of galactaric acid from D-galacturonic acid was generated. The present study highlights the usefulness of CRISPR/Cas9 technology in the metabolic engineering of filamentous fungi.
Pancreatic ductal adenocarcinoma (PDAC) shows great cellular heterogeneity, with pronounced epithelial and mesenchymal cancer cell populations. However, the cellular hierarchy underlying PDAC cell ...diversity is unknown. Here we identify the tetraspanin CD9 as a marker of PDAC tumour-initiating cells. CD9
cells had increased organoid formation capability, and generated tumour grafts in vivo at limiting dilutions. Tumours initiated from CD9
cells recapitulated the cellular heterogeneity of primary PDAC, whereas CD9
cells produced only duct-like epithelial progeny. CD9 knockdown decreased the growth of PDAC organoids, and heterozygous CD9 deletion in Pdx1-Cre; LSL-KRas
; p53
mice prolonged overall survival. Mechanistically, CD9 promoted the plasma membrane localization of the glutamine transporter ASCT2, enhancing glutamine uptake in PDAC cells. Thus, our study identifies a PDAC subpopulation capable of initiating PDAC and giving rise to PDAC heterogeneity, suggesting that the cellular diversity of PDAC is generated by PDAC stem cell differentiation.
Pharmacotherapy using natural substances can be currently regarded as a very promising future alternative to conventional therapy. With the rapid development of biotechnologies and analytical ...techniques, a great number of methods have been developed for the identification and quantification of the material, extracts, and products of natural ingredients. The advances available today. The need for safer drugs without side effects has led to the use of natural ingredients with proven safety. In recent years, some bioactive polysaccharides isolated from natural sources have attracted much attention in the field of biochemistry and pharmacology. As an example, polysaccharides or their glycoconjugates were shown to exhibit multiple biological activities including anticarcinogenic, anticoagulant, immunostimulating, antioxidant, etc. During the last several years, we have witnessed a steady expansion in the number of publications that focus in antioxidant polysaccharides. This review presents current findings on the latest advancements and trends in antioxidant polysaccharides isolated from the following: plants, fungi, bacteria, animal sources, and algae. Some interesting studies focus on investigation of the relationship between their structure and antioxidant activity, elucidation of their antioxidant mechanism at the molecular level, and improvement of their various biological activities by chemical modifications. Although the mechanism of their antioxidant action is still not completely clear, these polysaccharides are suggested to enhance cell-mediated immune responses in vivo and in vitro and act as biological response modifiers.
Abstract
Coronal mass ejections (CMEs) that originate from pseudostreamers, which separate coronal holes of the same magnetic polarity, are characterized by a narrow (∼5°–30°), fan-shaped appearance ...in white-light coronagraph images. Despite this striking morphological similarity, a wide variety of underlying eruptions are observed, including not only coronal jets, but also larger-scale filament eruptions, footpoint flares, and even extreme-ultraviolet (EUV) waves that reflect off the coronal hole boundaries. Using EUV images recorded by the Solar Dynamics Observatory during the early rising phase of cycle 25 (2020–2022), we describe examples of the different kinds of underlying eruptions and identify the corresponding fan-like ejections in Large Angle and Spectrometric Coronagraph images. We attribute the narrowness of the white-light CMEs to lateral confinement by the like-polarity open flux surrounding the pseudostreamer and point out that, although the multipolar topology facilitates the “breakout” of material through the cusp region, it also tends to inhibit the eruption of the pseudostreamer as a whole. We also note that the self-similar “continuum” formed by the pseudostreamer mass ejections does not include the larger, more space-weather-effective CMEs associated with helmet streamers, which are surrounded by open flux of opposite polarity and undergo much greater lateral expansion.
Purpose
To investigate whether growth hormone (GH) could improve pregnancy rates of patients with thin endometrium by clinical study and laboratory experiments.
Materials and methods
Ninety-three ...patients were randomized to either the GH-received group (40) or the routine exogenous administration of estrogens control group (53) for clinical study. The human endometrial carcinoma cell line RL95-2 was used for testing the role of GH with Western blot and real-time PCR by exposure to various concentrations of GH (0.1 nM,1 nM,10 nM,100 nM).
Results
Patients treated with GH had a significantly (
P
< 0.05) greater endometrium thickness on day 3 (7.87±0.72 vs 6.34±0.86), higher implantation rates (24.4% vs 10.5%) and greater clinical pregnancy rates (42.5% vs 18.9%) compared with the control group. No adverse events were associated with the use of GH. Administration of GH significantly up-regulated the expression of VEGF, ItgB3 and IGF-I expression in RL95-2 cells at both mRNA and protein levels (
P
< 0.05). AG490, an inhibitor of JAK2, nearly completely inhibited the up-regulative effect of GH through the JAK2-STAT5 pathway, and GH-induced effects could be mediated through autocrine IGF-I together with its hepatic counterpart. IGF-I mRNA was detected in the RL95-2 cells.
Conclusion
GH may improve pregnancy outcomes of patients with thin endometrium who undergo frozen embryo transfer by acting on human endometrial cells to promote proliferation and vascularization and to up-regulate receptivity-related molecular expression.
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