Magnetic nanoparticles immobilized thrombin ligand fishing to screen thrombin inhibitors in natural products.

In this study, thrombin was immobilized with magnetic particles modified by glutaraldehyde. The changes in secondary structures of immobilized enzyme revealed an increment in conformational rigidity and stability, which can be reflected in temperature and pH stability as well as the tolerance of organic reagents. The optimal reutilization times of magnetic particle immobilized thrombin were 7 times, and the half-life of enzyme activity preserved at room temperature was 5 days, which was 2.5 times higher than that of free enzyme. Ligusticum chuanxiong and Anemarrhenae Rhizoma with high enzyme inhibitory activity were selected for primary screening, and six potential inhibitors of thrombin were identified by HPLC/MS. The results showed that three compounds in Anemarrhenae Rhizoma had better predictive thrombin inhibitory activity. Through the in vitro thrombin activity inhibition experiment, it was also verified that mangiferin and neo-mangiferin had an ideal thrombin activity inhibition effect, which was consistent with the results of molecular docking.

Hysteresis analysis reveals how phytoplankton assemblage shifts with the nutrient dynamics during and between precipitation patterns.

The escalation of global eutrophication has significantly increased due to the impact of climate change, particularly the increased frequency of extreme rainfall events. Predicting and managing eutrophication requires understanding the consequences of precipitation events on algal dynamics. Here, we assessed the influence of precipitation events throughout the year on nutrient and phytoplankton dynamics in a drinking water reservoir from January 2020 to January 2022. Four distinct precipitation patterns, namely early spring flood rain (THX), Plum rain (MY), Typhoon rain (TF), and Dry season (DS), were identified based on rainfall intensity, duration time, and cumulative rainfall. The study findings indicate that rainfall is the primary driver of algal dynamics by altering nutrient levels and TN:TP ratios during wet seasons, while water temperature becomes more critical during the Dry season. Combining precipitation characteristics with the lag periods between algal proliferation and rainfall occurrence is essential for accurately assessing the impact of rainfall on algal blooms. The highest algae proliferation occurred approximately 20 and 30 days after the peak rainfall during the MY and DS periods, respectively. This was influenced by the intensity and cumulative precipitation. The reservoir exhibited two distinct TN/TP ratio stages, with average values of 52 and 19, respectively. These stages were determined by various forms of nitrogen and phosphorus in rainfall-driven inflows and were associated with shifts from Bacillariophyta-dominated to Cyanophyta-dominated blooms during the MY and DS seasons. Our findings underscore the interconnected effects of nutrients, temperature, and hydrological conditions driven by diverse rainfall patterns in shaping algal dynamics. This study provides valuable insights into forecasting algal bloom risks in the context of climate change and developing sustainable strategies for lake or reservoir restoration.

Solvent-like bis (2-chloro-1-methylethyl) ether occurrence in drinking water: Multidimensional risk assessment integrated health and aesthetic aspects.

Bis (2-chloro-1-methylethyl) ether (DCIP), one U.S. Environmental Protection Agency priority pollutant, could pose health and/or odor risk in water environment. In this study, odor characteristics, occurrence and source of DCIP in drinking waters of China were investigated based on sensory analysis and a nation-wide investigation covering 140 drinking water treatment plants. Then multi-risk integrated health and aesthetic aspects through oral and inhalation (showering) exposure by drinking water were first estimated. Sensory evaluation showed DCIP exhibited "solvent-like" odor with thresholds of 34.8 ng/L in air and 142.0 ng/L in water. DCIP was detected at comparable concentrations in raw and finished waters (<1280 ng/L) and was by-product from industrial production of epichlorohydrin/propylene oxide. Lifetime Average Daily Dose through oral exposure was 0-36.65 ng/day/kg, corresponding to odor activity values of 0-8.4 and hazard quotients of far < 1, indicating drinking tap water might cause odor issues rather than significant health hazard. The proportion of sensitive population to DCIP's odor was 6.1%. In contrast, residents rarely detect DCIP's odor by inhalation. The presence in drinking water as industrial by-product, poor removal using conventional water treatment and potential to be T&O issues, indicates urgent demand for pollutant source control to protect DCIP from entering source waters.

Efficacy of Yiqi Wenyang Huoxue method in treating adult bronchial asthma: A protocol for systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Bronchial asthma (BA) is a chronic inflammatory disease of the airway, which has the characteristics of recurrent attacks and difficult to cure. Glucocorticoid and bronchodilator are the primary treatment drugs for asthma. Although the treatment has made some progress, the control status is still not ideal. According to clinical reports, the Yi-qi Wen-yang Huo-xue method (YQWYHXM) of Traditional Chinese Medicine (TCM) is safe and effective in the treatment of BA, but there is not enough evidence to prove it. Based on it, we conducted this systematic evaluation. METHODS: Eight databases and Clinical trial registries (Embase, Cochrane, PubMed, CNKI, CBM, Wanfang, VIP, China Clinical Trial Registry and Clinical Trails) were searched from the establishment of those until January 22, 2021 with the following terms for retrieval: BS, TCM, Chinese medicinal herb, Chinese herbal medicine and randomized controlled trial. Data analysis was performed by 2 researchers using RevMan 5.3 and SATA 16.0 separately from the Cochrane Collaboration. RESULTS: This study will be able to provide definitive evidence to clarify all the suspicions we seek, confirming the effectiveness of YQWYHXM in the treatment of adults with BA. CONCLUSION: This study will prove that YQWYHXM is a safe and effective TCM adjuvant therapy for BA. REGISTRATION: Efficacy of Yiqi Wenyang Huoxue method in Treating Adult Bronchial Asthma. ASTHMA: A protocol for Systematic Review and Meta-Analysis of Randomized Controlled Trials. PROSPERO 2021 CRD42021256791. Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021256791.

Efficacy and safety of Hou Gu Mi Xi for peptic ulcer diseases: Study protocol for a randomized controlled trial.

BACKGROUND: Peptic ulcer disease (PUD) is a major burden worldwide. Several challenges remain with standard Western treatment of PUD, such as persistent weakness, fatigue, and relapse. A dietary traditional Chinese medicine (TCM) formula, Hou Gu Mi Xi (HGMX), has been developed as a complementary treatment for PUD. AIMS: This multicenter, double-blind, randomized controlled trial will assess efficacy and safety of HGMX in patients with PUD. METHODS: Three hundred sixty eligible patients will be assigned to receive HGMX, placebo, HGMX + rabeprazole or placebo + rabeprazole for 4 weeks after 2 weeks of standard Western treatment. This first step, with a 2 × 2 factorial design, will focus on assessing the main and interaction effects of HGMX and rabeprazole on ulcer healing. Then, rabeprazole will be stopped, and HGMX will be continued for up to 1 year. The second step, with a placebo-controlled design, will compare the long-term effects of HGMX and placebo. Extended follow-up with no treatment will continue for up to 2 years. Independent and paired t tests, Pearson χ test and the rank-sum test will be used to compare between-group differences. The P value will be adjusted using the O'Brien & Fleming method for multiple comparisons. EXPECTED OUTCOMES: The primary outcomes are total efficacy rate of PUD treatment, quality of ulcer healing, and changes in spleen qi deficiency symptoms. The secondary outcomes include ulcer area, PUD recurrence, Helicobacter pylori eradication rate, gastric function, body weight, and body mass index. Adverse events (AEs), severe AEs, treatment-related AEs, and withdrawal owing to AEs will be recorded to assess treatment safety. DISCUSSION: The trial results will provide high-quality evidence for HGMX, as a complementary therapy, for the long-term management of PUD and will be valuable for the development of related guidelines and regulations. TRIAL REGISTRATION: The protocol of this trial was approved in all research hospitals and was registered in ClinicalTrials.gov at October 25, 2017(No. NCT03320538).

[Influence of nutrient sources on Anabaena spiroides growth and odorous compounds production characteristics].

The occurrence of taste and odors, produced by secondary metabolites of cyanobacteria, has been one of the major water quality problems in drinking water. However, the odorous compounds produced by cyanobacteria usually differ significantly with different species. One cyanobacterium isolated from Yanghe reservoir was identified as Anabaena sp., which can produce high level of geosmin consistently during laboratory culture. By culture expanding experiments, the algal growth and geosmin production characteristics of the Anabaena sp. were studied on different conditions of nitrogen and phosphorus sources. The results indicated that geosmin mainly remained in the intracellular algal cells regardless of the nutrient sources, and the extracellular content was only in th range of 0.2% - 9.6%. Compared with ammonia nitrogen conditions, the growth of Anabaena sp. in nitrate nitrogen conditions was much higher, with a 1.4-fold variation in geosmin production. While ammonia nitrogen concentration was 0.5 mg/L, the algal biomass and geosmin production achieved the highest level of 3.8 x 10(4) cells, mL(-1) and 1.1 x 10(4) ngL(-1), respectively. When the nitrate nitrogen concentration was 2.0 mg/L, the algal biomass and geosmin production achieved the highest level of 6.6 x 10(4) cells x mL(-1) and 1.3 x 10(4) ng x L(-1), respectively. Compared with nitrogen sources, the growth of Anabaena sp. could be promoted significantly until phosphorus level attained 0.12 mg/L, indicating that phosphorus is the main limiting nutrient source for Anabaena sp.. For Yanghe reservoir, the nutrient level has already been enough for the growth of Anabaena sp. Therefore, the nutrient source content, especially phosphorus, should be reduced effectively to control the cyanobacterium bloom and taste and odor problems.