UV-based solvent system screening for high-speed counter-current chromatography fractionation of compounds with similar UV absorption from complex samples followed by preparative HPLC purification: Flavonoids from barley seedlings as sample.

This article proposes a solvent system screening strategy for compounds with similar UV absorption in complex samples by UV spectrophotometer. There is no need to calculate the partition coefficient value of each compound, only the partition coefficient of the whole sample. The partition coefficient value should be close to 1 in order to obtain as many high-speed counter-current chromatography fractions as possible. Then, preparative HPLC was used to purify the high-speed counter-current chromatography fractions. Based on the above strategy, seven c-glycosyl flavonoids and an amino acid were successfully obtained from barley seedlings through high-speed counter-current chromatography fractionation with ethyl acetate/n-butanol/water (8:2:10, v:v:v) system followed by preparative HPLC purification. The research shows that high-speed counter-current chromatography could be well developed as a tool for fractionation before purification, and greatly improves the separation efficiency.

Associations Between Elevated Plasma Total Homocysteine Level and Risk of Thromboangiitis Obliterans in a Chinese Population: A Matched Case-Control Study.

BACKGROUND: Elevated plasma total homocysteine level is a risk factor for various vascular diseases; however, an association with risk of thromboangiitis obliterans (TAO) has not been defined. This study aims to assess whether elevated plasma total homocysteine level is associated with risk of TAO. METHODS: We performed a matched case-control study including 64 patients with TAO and 256 controls. Multivariate logistic regression models were used to estimate the association between elevated plasma homocysteine level and the risk of TAO. Interaction and stratified analyses were conducted according to age, sex, smoking, alcohol consumption, and histories of chronic diseases. RESULTS: Patients with TAO versus controls had a higher mean plasma total homocysteine level (21.2 ± 12.8 µmol/L vs. 14.1 ± 4.9 µmol/L; P < 0.01). The risk of TAO was 3.68-fold increased in participants with plasma total homocysteine level >15 µmol/L (95% confidence interval [95% CI], 1.2-11.7). A 1 µmol/L increase in plasma total homocysteine level was associated with 20% higher risk of TAO (odds ratio, 1.2; 95% CI, 1.1-1.3). CONCLUSIONS: Our findings suggest that the risk of TAO was significantly associated with elevated plasma total homocysteine level independently of other factors analyzed, including smoking. Studies on the use of homocysteine-lowering therapy to prevent TAO would allow testing causality of the latter association.

Consistency of Proximal-to-Distal Tapering of Descending Thoracic Aortic Diameter: Quantification Using a Novel Computer Tomography-based Assessment.

BACKGROUND: Successful endovascular repair of thoracic aorta for type B aortic dissection requires correct stent-graft sizing, particularly of distal landing zone which is mainly based on operator experience. The present study aimed to quantitatively define proximal-to-distal tapering of descending thoracic aortic diameter and its consistency. METHODS: The novel parameter HDP (Hundred times Distance accounts for Percentage)-measured as distance from the distal end of the left subclavian artery to each level along the aortic central line/length from the distal end of the left subclavian artery to the proximal end of the celiac artery along the aortic central line × 100-was calculated per 1% unit of descending thoracic aorta based on 3-mensio software-derived measurements from 281 consecutive individuals who had undergone enhanced chest computer tomography scanning. Association between HDP and maximal diameter of descending thoracic aorta was assessed by using the generalized additive mixed model with smoothing function and threshold saturation effect analyses with generalized estimating equations. Nonadjusted and adjusted models were performed to illuminate its consistency. RESULTS: Three inflection levels (HDPs of 15.01, 36.63, and 77.74) were identified which allowed to divide the descending thoracic aorta into 4 segments. The taper was consistent before and after adjusting for age, sex, height, body mass index, hypertension, smoking habits, hyperlipidemia, and diabetes. Although 1% unit of descending thoracic aorta decreases, the maximal diameter reduces to 0.007 mm (-0.025, 0.010; P = 0.414) in the segment with HDP <15.01, to 0.151 mm (-0.158, -0.145; P < 0.001) in the segment with 15.01 ≤ HDP < 36.63, to 0.038 mm (-0.040, -0.036; P < 0.001) in the segment with 36.63 < HDP ≤ 77.74; and to 0.026 mm (-0.049, -0.002; P = 0.035) in the segment with HDP > 77.74, respectively. CONCLUSIONS: The maximal diameter of descending thoracic aorta decreases gradually and consistently among individuals free of aortic diseases.

Optimization of Ultrasonic-Assisted Extraction and Purification of Zeaxanthin and Lutein in Corn Gluten Meal.

Zeaxanthin and lutein have a wide range of pharmacological applications. In this study, we conducted systematic experimental research to optimize antioxidant extraction based on detection, extraction, process amplification, and purification. An ultrasonic-assisted method was used to extract zeaxanthin and lutein with high efficiency from corn gluten meal. Firstly, the effects of solid-liquid ratio, extraction temperature, and ultrasonic extraction time on the extraction of zeaxanthin were investigated in single-factor experiments. The optimization extraction parameters of zeaxanthin and lutein with ethanol solvent were obtained using the response surface methodology (RSM) as follows: liquid-solid ratio of 7.9:1, extraction temperature of 56 °C, and extraction time of 45 min. The total content of zeaxanthin and lutein was 0.501%. The optimum extraction experimental parameters were verified by process amplification, and we confirmed that the parameters of the extraction process optimized using the RSM design are reliable and precise. Zeaxanthin and lutein from crude extract of corn gluten were separated and purified using silica gel column chromatography with the purity of zeaxanthin increasing from 0.28% to 31.5% (about 110 times) and lutein from 0.25% to 16.3% (about 65 times), which could be used for large-scale industrial production of carotenoids.

Highly-dispersed 2D NiFeP/CoP heterojunction trifunctional catalyst for efficient electrolysis of water and urea.

The electrocatalytic production of "green hydrogen", such as through the electrolysis of water or urea has been vigorously advocated to alleviate the energy crisis. However, their electrode reactions including oxygen evolution reaction (OER), urea oxidation reaction (UOR), and hydrogen evolution reaction (HER) all suffer from sluggish kinetics, which urgently need catalysts to accelerate the processes. Herein, we design and prepare an OER/UOR/HER trifunctional catalyst by transforming the homemade CoO nanorod into a two-dimensional (2D) ultrathin heterojunction nickel-iron-cobalt hybrid phosphides nanosheet (NiFeP/CoP) via a hydrothermal-phosphorization method. Consequently, a strong electronic interaction was found among the Ni2P/FeP4/CoP heterogeneous interfaces, which regulates the electronic structure. Besides the high mass transfer property of 2D nanosheet, Ni2P/FeP4/CoP displays improved OER/UOR/HER performance. At 10 mA cm-2, the OER overpotential reaches 274 mV in 1.0 M KOH, and the potential of UOR is only 1.389 V in 1.0 M KOH and 0.33 M urea. More strikingly, the two-electrode systems for electrolysis water and urea-assisted electrolysis water assembled by NiFeP/CoP could maintain long-term stability for 35 h and 12 h, respectively. This work may help to pave the way for upcoming research horizons of multifunctional electrocatalysts.

Aortic hemodynamic and morphological analysis before and after repair of thoracoabdominal aortic aneurysm using a G-Branch endograft.

Background and objective: The G-Branch endograft is a novel multibranched "off-the-shelf" device used to repair thoracoabdominal aortic aneurysms (TAAAs). This report describes the hemodynamic and morphological performance of the G-Branch endograft in a human patient with TAAA. Materials and methods: We retrospectively reviewed the computed tomography angiography scans and clinical data of a woman in whom TAAA was treated using a G-Branch endograft. Patient-specific three-dimensional models were reconstructed, and computational fluid dynamics and morphological and hemodynamic indicators were analyzed before and after implantation of the device. Results: From a morphological perspective, there was an increase in cross-sectional area in the G-Branch endograft and all bridging stent grafts over time. Blood flow was redistributed among the renovisceral arteries, with a decrease in flow rate in the celiac artery and an increase in the left renal artery. Laminar blood flow was smoother and more rapid after implantation of the G-Branch device and remained stable during follow-up. In the bridging stent grafts, flow recirculation zones were found in the bridging zones of the celiac artery and superior mesenteric artery as well as the distal sealing zones of both renal arteries. Furthermore, higher time-averaged wall shear stress and a lower oscillatory index and relative resident time were found in the G-Branch endograft and bridging stent grafts. Quantitative analysis showed obvious reduction in the surface area ratio of the elevated time-averaged wall shear stress area and surface area ratio of the relative resident time after G-branch implantation. Conclusion: The revascularization of branch vessels occurred following G-branch implantation, with improvements arising not only from morphological changes but also from hemodynamic alterations. The long-term performance of the G-Branch endograft needs further investigation and clinical validation.

Murine model of elastase-induced proximal thoracic aortic aneurysm through a midline incision in the anterior neck.

Objective: This study was performed to develop a murine model of elastase-induced proximal thoracic aortic aneurysms (PTAAs). Methods: The ascending thoracic aorta and aortic arch of adult C57BL/6J male mice were exposed through a midline incision in the anterior neck, followed by peri-adventitial elastase or saline application. The maximal ascending thoracic aorta diameter was measured with high-resolution micro-ultrasound. Twenty-eight days after the operation, the aortas were harvested and analyzed by histopathological examination and qualitative polymerase chain reaction to determine the basic characteristics of the aneurysmal lesions. Results: Fourteen days after the operation, the dilation rate (mean ± standard error) in the 10-min elastase application group (n = 10, 71.44 ± 10.45%) or 5-min application group (n = 9, 42.67 ± 3.72%) were significantly higher than that in the saline application group (n = 9, 7.37 ± 0.94%, P < 0.001 for both). Histopathological examination revealed aortic wall thickening, degradation of elastin fibers, loss of smooth muscle cells, more vasa vasorum, enhanced extracellular matrix degradation, augmented collagen synthesis, upregulated apoptosis and proliferation capacity of smooth muscle cells, and increased macrophages and CD4+ T cells infiltration in the PTAA lesions. Qualitative analyses indicated higher expression of the proinflammatory markers, matrix metalloproteinase-2 and -9 as well as Collagen III, Collagen I in the PTAAs than in the controls. Conclusion: We established a novel in vivo mouse model of PTAAs through a midline incision in the anterior neck by peri-adventitial application of elastase. This model may facilitate research into the pathogenesis of PTAA formation and the treatment strategy for this devastating disease.

The clinical efficacy of collagen dressing on chronic wounds: A meta-analysis of 11 randomized controlled trials.

Objective: This study aims to evaluate the clinical efficacy of collagen dressing for patients with chronic wounds. Materials and methods: Relevant randomized controlled trials were searched from the databases such as PubMed, EMBASE, and the Cochrane library as of January 2022. For dichotomous outcomes and continuous outcomes, risk ratio and mean difference were calculated, respectively. Subgroup analysis was performed according to the type of chronic ulcer and follow-up. In addition, trial sequential analysis (TSA) was performed to further verify the results. Jadad score was used to assess the quality of trials. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was utilized to assess the level of evidence for outcomes. Results: In 11 studies, a total of 961 patients of whom 485 were in the collagen group. Compared with standard of care (SOC) alone, the group that added an extra collagen dressing achieved a higher wound healing rate (Risk Ratio = 1.53; 95% CI, 1.33-1.77). The collagen group also showed a higher healing velocity than the SOC group (Mean Difference, 2.69; 95% CI, 0.87-4.51). In addition, the adverse events related to dressing between the two groups were similar (Risk Ratio = 0.67; 95% CI, 0.44-1.01). Conclusion: Collagen dressing increases the wound healing rate and may be an effective and safe treatment for chronic wound management. However, more extensive research shall be conducted to substantiate these results. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=245728, identifier: CRD42021245728.

Optimized extraction of astaxanthin from shrimp shells treated by biological enzyme and its separation and purification using macroporous resin.

The best enzymatic protease treatment of shrimp shells was identified by comparing the enzymatic hydrolysis effects of many different types of biological enzymes using fresh Arctic sweet shrimp as raw materials. The optimal enzymolysis conditions were determined using neutral protease as the best enzymatic protease. Among multiple macroporous adsorption resins, XDA-8 macroporous adsorption resin was preferable due to its static adsorption rate and desorption rate. The yield of astaxanthin (134.20 µg/g) after treatment with neutral protease was 3.7 times higher than that of the control group (36.03 µg/g). The yield of astaxanthin was obviously improved after enzymolysis of the shrimp shells. The purity of the astaxanthin was up to 87.34%, approximately 6508 times higher than that of the raw material. The production cost of astaxanthin would be greatly reduced by use of XDA-8 resin to obtain high-purity astaxanthin. This technique offers a high value-added utilization of shrimp shells.

Pterostilbene reduces endothelial cell apoptosis by regulation of the Nrf2-mediated TLR-4/MyD88/NF-κB pathway in a rat model of atherosclerosis.

Endothelial cell injury in vascular arterial walls plays a crucial role in the pathological process of atherosclerosis. Pterostilbene, a stilbenoid chemically related to resveratrol, has anti-inflammatory, anti-apoptosis and antioxidant properties. However, the underlying mechanisms mediated by pterostilbene in regards to endothelial cell injury in vascular arterial walls are not fully understood. The purpose of the present study was to investigate the benefits of pterostilbene in a rat model of atherosclerosis. The possible mechanism of pterostilbene was also analyzed in regards to endothelial cell injury in vascular arterial walls in vitro. A rat model of atherosclerosis was established using endothelial injury of the iliac arteries. CCK-8 assay, TUNEL, immunofluorescence, western blot analysis and hematoxylin and eosin (H&E) staining were used to analyze the role of pterostilbene in the pathological processes of atherosclerosis. In vivo results showed that pterostilbene decreased cholesterol (CHO), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) in plasma and attenuated interleukin (IL)-1, tumor necrosis factor (TNF)-α and IL-6 and oxidative stress injury in serum in the experimental animals. Pterostilbene treatment reduced atherogenesis, aortic plaques, macrophage infiltration and apoptosis of vascular arterial walls in the atherosclerosis rat model. In vitro assay demonstrated that pterostilbene administration increased viability of the endothelial cells, attenuated oxidative stress injury and apoptosis of endothelial cells. The results found that pterostilbene regulated endothelial cell apoptosis via the Nrf2-mediated TLR-4/MyD88/NF-κB pathway. In conclusion, data from the present study revealed that pterostilbene protects rats against atherosclerosis by regulation of the Nrf2-mediated TLR-4/MyD88/NF-κB pathway.