Silicon and selenium alleviate cadmium toxicity in Artemisia selengensis Turcz by regulating the plant-rhizosphere.

Soil cadmium (Cd) pollution has emerged as a pressing concern due to its deleterious impacts on both plant physiology and human well-being. Silicon (Si) is renowned for its ability to mitigate excessive Cd accumulation within plant cells and reduce the mobility of Cd in soil, whereas Selenium (Se) augments plant antioxidant capabilities and promotes rhizosphere microbial activity. However, research focusing on the simultaneous utilization of Si and Se to ameliorate plant Cd toxicity through multiple mechanisms within the plant-rhizosphere remains comparatively limited. This study combined hydroponic and pot experiments to investigate the effects of the combined application of Si and Se on Cd absorption and accumulation, as well as the growth and rhizosphere of A. selengensis Turcz under Cd stress. The results revealed that a strong synergistic effect was observed between both Si and Se. The combination of Si and Se significantly increased the activity and content of enzymes and non-enzyme antioxidants within A. selengensis Turcz, reduced Cd accumulation and inhibiting its translocation from roots to shoots. Moreover, Si and Se application improved the levels of reducing sugar, soluble protein, and vitamin C, while reducing nitrite content and Cd bioavailability. Furthermore, the experimental results showed that the combination of Si and Se not only increased the abundance of core rhizosphere microorganisms, but also stimulated the activity of soil enzymes, which effectively limited the migration of Cd in the soil. These findings provided valuable insights into the effective mitigation of soil Cd toxicity to plants and also the potential applications in improving plant quality and safety.

Percutaneous Transhepatic Papillary Balloon Dilation versus Endoscopic Retrograde Cholangiopancreatography for Common Bile Duct Stones: A Multicenter Prospective Study.

Background Endoscopic retrograde cholangiopancreatography (ERCP) is recommended by major guidelines for the removal of common bile duct (CBD) stones but is technically challenging in patients with low cardiopulmonary reserve and anatomic abnormalities of the upper gastrointestinal (GI) tract. Purpose To compare percutaneous transhepatic papillary balloon dilation (PTPBD) with ERCP for CBD stone removal. Materials and Methods Participants with one to three CBD stones (largest stone ≤30 mm) and without intrahepatic bile duct or gallbladder stones were eligible for this prospective cohort study. PTPBD was recommended in participants with low cardiopulmonary reserve or definitive anatomic abnormalities of the upper GI tract. Otherwise, both procedures were offered without preference. Follow-up, including abdominal CT, was conducted at 1-week and 1-, 3- and 6-month follow-up, and every 6 months thereafter. US and MR cholangiopancreatography were conducted if recurrence could not be confirmed with CT. Technical success rate was the primary outcome. Results A total of 531 participants were analyzed: there were 360 undergoing PTPBD (median age, 76 years; interquartile range [IQR], 64-82 years; 163 men) and 171 undergoing ERCP (median age, 66 years; IQR, 57-74 years; 94 men). The technical success rate was 99% (355 of 360) in the PTPBD group and 98% (167 of 171) in the ERCP group (relative risk, 1.02; P = .12). The incidence of overall complications was 4% (13 of 360) for PTPBD and 8% (13 of 171) for ERCP (relative risk, 0.27; 95% CI: 0.12, 0.61; P < .001). The PTPBD group showed a longer fluoroscopy time and a higher radiation exposure, with adjusted differences of 28.7 minutes (95% CI: 22.2, 35.2) and 384.3 mGy (95% CI: 296.5, 472), respectively. A propensity score-matching analysis (n = 123 per group) indicated that PTPBD had a slightly higher technical success rate and significantly fewer complications. Conclusion When compared with endoscopic retrograde cholangiopancreatography, percutaneous transhepatic papillary balloon dilation has a similar technical success rate and fewer perioperative complications but a higher radiation exposure. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by van Sonnenberg and Mueller in this issue.

1,2-trans-Stereoselective Synthesis of C-Glycosides of 2-Deoxy-2-amino-sugars Involving Glycosyl Radicals.

We report for the first time that the imidate radical can be efficiently added to glycals to generate glycosyl radicals, based on which a general, toxic-reagent-free synthesis of C-glycosides of 2-deoxy-2-amino sugars has been developed. Complementary to previous strategies, the reaction is 1,2-trans-stereoselective and could use aryl alkenes as substrates. The late-stage functionalization and density functional theory calculations are reported.

Diastereoselective synthesis and conformational analysis of 4,5-difluoropipecolic acids.

Stereoselectively-fluorinated analogs of pipecolic acid have been investigated through a combined theoretical and experimental approach. Three of the four possible diastereoisomers of 4,5-difluoropipecolic acid were successfully synthesized via deoxyfluorination chemistry, navigating a complex reaction network that included neighboring group participation, rearrangement, and elimination pathways. A DFT-based conformational study, supported by NMR J-based analysis, revealed that the different diastereoisomers of 4,5-difluoropipecolic acid preferentially adopt different puckers of the six-membered ring. These findings could have future relevance for the conformational control of biologically active peptides.

Diagnostic value of 3D time-of-flight MRA in trigeminal neuralgia.

The aim of this meta-analysis was to evaluate the diagnostic value of 3D time-of-flight magnetic resonance angiography (3D-TOF-MRA) in trigeminal neuralgia (TN). Relevant studies were identified by computerized database searches supplemented by manual search strategies. The studies were included in accordance with stringent inclusion and exclusion criteria. Following a multistep screening process, high quality studies related to the diagnostic value of 3D-TOF-MRA in TN were selected for meta-analysis. Statistical analyses were conducted using Statistical Analysis Software (version 8.2; SAS Institute, Cary, NC, USA) and Meta Disc (version 1.4; Unit of Clinical Biostatistics, Ramon y Cajal Hospital, Madrid, Spain). For the present meta-analysis, we initially retrieved 95 studies from database searches. A total of 13 studies were eventually enrolled containing a combined total of 1084 TN patients. The meta-analysis results demonstrated that the sensitivity and specificity of the diagnostic value of 3D-TOF-MRA in TN were 95% (95% confidence interval [CI] 0.93-0.96) and 77% (95% CI 0.66-0.86), respectively. The pooled positive likelihood ratio and negative likelihood ratio were 2.72 (95% CI 1.81-4.09) and 0.08 (95% CI 0.06-0.12), respectively. The pooled diagnostic odds ratio of 3D-TOF-MRA in TN was 52.92 (95% CI 26.39-106.11), and the corresponding area under the curve in the summary receiver operating characteristic curve based on the 3D-TOF-MRA diagnostic image of observers was 0.9695 (standard error 0.0165). Our results suggest that 3D-TOF-MRA has excellent sensitivity and specificity as a diagnostic tool for TN, and that it can accurately identify neurovascular compression in TN patients.

Optimization of microwave-assisted FeCl3 pretreatment conditions of rice straw and utilization of Trichoderma viride and Bacillus pumilus for production of reducing sugars.

In this study, Box-Behnken design (BBD) and response surface methodology (RSM) were used to optimize microwave-assisted FeCl(3) pretreatment conditions of rice straw with respect to FeCl(3) concentration, microwave intensity, irradiation time and substrate concentration. When rice straw was pretreated at the optimal conditions of FeCl(3) concentration, 0.14 mol/L; microwave intensity, 160°C; irradiation time, 19 min; substrate concentration, 109 g/L; and inoculated with Trichoderma viride and Bacillus pumilus, the production of reducing sugars was 6.62 g/L. This yield was 2.9 times higher than that obtained with untreated rice straw. The microorganisms degraded 37.8% of pretreated rice straw after 72 h. The structural characteristic analyses suggest that microwave-assisted FeCl(3) pretreatment damaged the silicified waxy surface of rice straw, disrupted almost all the ether linkages between lignin and carbohydrates, and removed lignin.