Search

In this work, various chalcone derivatives incorporating piperazine-isopropanolamine were elaborately designed and synthesized. The antibacterial efficacy revealed that compound Z6 showed notable biological activity, with a median effective concentration (EC50) of 0.29 mg/L against Xanthomonas oryzae pv. oryzae (Xoo) in vitro, which is around 200 times higher than thiodiazole copper (TC, 91.00 mg/L). Similarly, Z21 exhibited a strong biological response (EC50 = 0.83 mg/L) against Xanthomonas axonopodis pv. citri (Xac), outperforming TC (EC50 = 114.60 mg/L). Results of bioactivity test in vivo demonstrate that Z6 displayed significantly better curative and protective activities (51.5 %, 47.9 %) than TC (47.9 %, 30.5 %) against rice bacterial leaf blight (BLB). Further biochemical studies indicates that Z6 targeted multiple virulence factors and repressed the release of essential nutrients required for bacterial proliferation, thereby disrupting the reduction of cell membrane content of the pathogenic bacteria. According to the research, chalcone derivatives containing piperazine-isopropanolamine have potential to be antibacterial candidates.

A series of flavonol derivatives containing piperidine sulfonamide were designed and synthesized. The EC50 values for the curative of tobacco mosaic virus (TMV) by Z6 and Z22 were 108.2 and 102.7 μg/mL, respectively, outperforming the control agent ningenmycin (NNM) with an EC50 value of 253.8 μg/mL. Additionally, the EC50 values for the protective activity of Z6 and Z21 were 100.9 and 123.2 μg/mL, respectively, also surpassing the control agent NNM with an EC50 value of 203.7 μg/mL. Microscale thermophoresis (MST) and molecular docking test showed that Z6 bound well with tobacco mosaic virus coat protein (TMV-CP). The biological safety test showed that Z6 had almost no effect on seed germination and seedling growth. After treatment with Z6, the chlorophyll content and superoxide dismutase (SOD) activity in tobacco leaves increased, while the malondialdehyde (MDA) content decreased. Therefore, Z6 has a high probability as a potential antiviral agent.

Abstract Background Traditional pesticides are poorly water-soluble and suffer from low bioavailability. N-succinyl chitosan (NSCS) is a water-soluble chitosan derivative, has been recently used to encapsulate hydrophobic drugs to improve their bioavailability. However, it remains challenging to synthesize pesticides of a wide variety of water-soluble drugs and to scale up the production in a continuous manner. Results A synthetic method for preparing water-soluble nanopesticides with a polymer carrier was applied. The bioactive molecule BTL-11 was loaded into hollow NSCS to promote drug delivery, improve solubility and anti-fungal activity. The synthesized nanopesticides had well controlled sizes of 606 nm and the encapsulation rate was 80%. The release kinetics, drug toxicity and drug activity were further evaluated. The inhibitory activity of nanopesticides against Rhizoctonia solani (R. solani) was tested in vivo and in vitro. In vivo against R. solani trials revealed that BTL-11 has excellent control efficiency for cultivated rice leaf and sheath was 79.6 and 76.5%, respectively. By contrast, for BTL-11@NSCS NPs, the anti-fungal ability was strongly released and afforded significant control efficiencies of 85.9 and 81.1%. Those effects were significantly better than that of the agricultural fungicide azoxystrobin (51.5 and 66.5%). The proposed mechanism was validated by successfully predicting the synthesis outcomes. Conclusions This study demonstrates that NSCS is a promising biocompatible carrier, which can enhance the efficacy of pesticides, synergistically improve plant disease resistance, protect crop growth, and can be used for the delivery of more insoluble pesticides. Graphical Abstract

A series of flavonoid derivatives containing 1,2,4-triazolo[4,3-a]pyridine were designed, synthesized and evaluated for their antifungal activity. Bioactivity tests showed that some target compounds exhibited the strong antifungal activity against Botrytis cinerea (B. cinerea), Sclerotinia sclerotiorum (S. sclerotiorum), and Phomopsis sp. Among them, the half maximal effective concentration (EC50) value of S2 against B. cinerea was 3.3 μg/mL, which was less than that of the control drug azoxystrobin (21.0 μg/mL). The EC50 value of S2 against S. sclerotiorum was 12.7 μg/mL, which was better than that of azoxystrobin (28.1 μg/mL). In addition, the in vivo protective and curative activities of S2 against blueberry were 92.0 and 79.8 % at 200 μg/mL, respectively, which were higher than those of the control drug azoxystrobin (89.4 and 71.7 %). Scanning electron microscopy (SEM) and spore germination experiments showed that S2 could not only cause the mycelium damage but also inhibited the spore germination. Fluorescence microscopy (FM) observation, relative electrical conductivity measurement and cytoplasmic leakage assays indicated that S2 could affect cell membrane integrity by inducing lipid peroxidation and increasing cell membrane permeability as well as causing leakage of cytoplasmic contents. These results show that flavonoid derivatives containing 1,2,4-triazolo[4,3-a]pyridine had excellent inhibitory effects on B. cinerea, providing another supplement for the development of new pesticides.

In this study, 24 chalcone derivatives containing benzoxazole were designed and synthesized, and the structures of all target compounds were confirmed by NMR and HRMS. The results of antibacterial activity showed that the median effective concentration (EC50) value of Z2 against Xanthomonas oryzae pv.oryzae (Xoo) was 8.10 μg/mL, which was better than thiodiazole copper (60.62 μg/mL), the antibacterial activity of Z2 was verified by scanning electron microscopy (SEM). Antibacterial mechanism of Z2 on Xoo was preliminarily explored, and the results showed concentrations were 100, 50 mg/L, which had a good cell membrane permeability to Xoo and can inhibit the EPS content and the production of extracellular enzymes, affecting the formation of biofilm, preliminary validation of the antibacterial effect of Z2 on Xoo. At 200 mg/L, Z2 had a better protective activity on harvested potatoes, which was comparable with thiodiazole copper. The activity against tobacco mosaic virus (TMV) was determined with half leaf dry spot method. The EC50 value of curative activity of Z15 was 101.97 μg/mL, which was superior to ningnanmycin (NNM) 294.27 μg/mL, and the EC50 value of protective activity of Z16 was 104.05 μg/mL, which was superior to NNM 185.73 μg/mL. Molecular docking results showed Z15, Z16 had a significantly higher affinity with tobacco mosaic virus coat protein (TMV-CP) than NNM. The above results indicated that chalcone derivatives containing benzoxazole have the potential to become antibacterial and antivirial agents.

A series of myricetin derivatives containing phenoxypyridine structure were designed and synthesized on the basis of the natural product myricitrin, which were structurally characterized on NMR and HRMS. The results of antiviral activity tests showed that some of the target compounds exhibited better inhibitory effects. Among them, B19 and B21 showed better curative activity with EC50 values of 195.67 and 173.64 μg/mL, respectively, which were superior to that of the control agent ningnanmycin(NNM) (238.30 μg/mL). B21 showed better protective activity with EC50 value of 236.37 μg/mL, which was better than that of the control agent NNM (269.89 μg/mL). The results of microcalorimetry showed that B1, B19 and B21 had good binding affinity with tobacco mosaic virus capsid protein (TMV-CP), and the Kd values were 0.059, 0.093 and 0.069 μM, which was higher than that of NNM (Kd = 2.78 μM). The molecular docking results showed that the hydrogen bond lengths between B1, B21 and the key amino acid residues of TMV-CP were shorter and with more tightly bound than those of NNM. In B21-treated tobacco leaves, chlorophyll content and superoxide dismutase (SOD) activity were significantly elevated, indicating that B21 can participate in regulating plant photosynthesis as well as defense enzymes and inducing plants to improve disease resistance.

Postmenopausal osteoporosis is the main cause of fractures in women. Resistance exercise has a positive effect on bone mineral density in postmenopausal osteoporosis patients, but its mechanism is unclear. The purpose of this study was to explore the mechanism of resistance exercise in improving ovariectomized osteoporotic rats based on the transcriptome sequencing technique. Eighteen female Sprague-Dawley rats were randomly divided into the sham-operated group, the non-exercise group, and the resistance exercise group. The rat model of postmenopausal osteoporosis was established by bilateral ovariectomy. Ten weeks after the operation, the resistance exercise group received 2 weeks of adaptive training, and 12 weeks of resistance exercise began in the 13th week. The rats were trained 5 days per week, in 4 sets of 3 repetitions per day. After the intervention, all rats were sacrificed, and the body weight, bone mineral density, trabecular bone microarchitecture, and bone biomechanics were examined. At the same time, RNA-seq and enrichment analysis of gene ontology and Kyoto Encyclopedia of Genes and Genomes were performed on the left tibias, followed by Elisa and RT-qPCR verification. It had been found that resistance exercise can effectively counteract the weight gain of ovariectomized osteoporotic rats, and has a good effect on bone mineral density and trabecular bone microarchitecture. Enrichment analysis showed that regulation of gene expression and osteoclast differentiation is the most closely related biological process and signaling pathway shared by RE/Ovx and NE/Ovx groups. Our results revealed that resistance exercise can play a role in inhibiting osteoclast activation and preventing the enhancement of osteoclast bone resorption function in ovariectomized osteoporotic rats by inhibiting Fos/Fosb-regulated TRAP activation and relieving Calcr inhibition, which has important application value in preventing bone loss caused by estrogen deficiency.

Soil erosion results in dissolved organic matter (DOM) loss and is one of the main paths of soil carbon loss. Bacteria affect the generation and transformation of DOM. However, the effect of bacteria on the composition and slope distribution of DOM has rarely been investigated under field conditions. Based on a long-term experiment of three gradients (3°, 5°, 8°) in a black soil erosion area of Northeast China, the content, composition, and source of DOM were studied. The results showed that the DOM of the 3° and 5° slope was enriched midslope, and the DOM of the 8° slope was enriched downslope. Parallel factor (PARAFAC) analysis indicated that the main substances in DOM were fulvic-like acid, humic-like acid, tryptophan-like protein, and soluble microbial metabolites. The upslope and downslope soils of 3° and 5° slopes showed high DOM bioavailability, while the downslope soil of the 8° slope showed high DOM bioavailability. The content of new DOM in downslope soil increased with the gradient. Bacteria played an important role in the synthesis and transformation of DOM and affected its composition and slope distribution. Verrucomicrobiota, Firmicutes, Planctomycetota, and Gemmatimonadota were the main factors affecting soil DOM. The results could be helpful in understanding the loss mechanism of DOM in eroded black soil and provide support for soil carbon sequestration.

Objective: The aim of this study was to evaluate the effect of electroacupuncture (EA) combined with medication on clinical efficacy, pain scores (Visual Analogue Scale, [VAS]), Disease Activity Score in 28 joints (DAS28), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and adverse events in treating patients with rheumatoid arthritis (RA). Methods: A systematic search of PubMed, the Cochrane Library, Web of Science, Embase, SinoMed, China National Knowledge Infrastructure, Wanfang, and VIP until December 12, 2021 was used to identify randomized controlled trials (RCTs) on the EA treatment of RA. Study selection and data extraction were performed critically and independently by two reviewers. Cochrane criteria for risk of bias was used to evaluate the methodological quality of the trials. The Grading of Recommendations Assessment, Development, and Evaluation Methodology (GRADE) was applied to assess the quality of evidence from quantitative analysis. Results: Seventeen RCTs, including 1317 patients, satisfied the inclusion criteria. Compared with the control group, EA combined with medication had a superior effect on clinical efficacy (RR = 1.25 [95% CI = 1.18 to 1.33], P

Purpose: This study aimed to explore whether the attitudes of nursing students toward the use of mobile learning are positive or negative and to identify the factors influencing their attitudes by reviewing the literature. Methods: Electronic search of six databases, including PubMed, the Cumulative Index of Nursing and Allied Health Literature, ProQuest, Web of Science, EMBASE, and Cochrane Library, was conducted, and relevant references within articles were manually searched. Retrieval time was from inception to October 21, 2020. The literature review was conducted in accordance with the PRISMA guidelines and the integrative review method. The Mixed Method Appraisal Tool (MMAT) was used for quality assessment. Results: A total of 316 articles were identified, and 18 English-language studies were finally included by reviewing titles, abstracts, and full text. Six quantitative, five qualitative, and seven mixed-method articles related to nursing students’ attitudes toward the use of mobile learning were identified. The results showed that most nursing students had positive attitudes toward mobile learning. Although students expressed strong intentions for mobile learning, the actual usage rate in practical settings was low. Several advantageous factors included usefulness, convenience, and ease of use, whereas disadvantageous factors included hardware facility, updated content, and software stability. Conclusion: Most nursing students have positive attitudes and willingness to mobile learning, but the actual use rate remains low. Advantageous and disadvantageous factors coexist. Further studies are needed to assess how mobile learning improves nursing students’ clinical knowledge and improves patient care.

Abstract The increasing prevalence of depression and diabetes mellitus has become a major public health problem worldwide. Studies have shown that people with diabetes are at a high risk of being diagnosed with depression, and diabetes complicates depression treatment by promoting the deterioration of glycemic control, reducing self-care ability and quality of life, and causing severe functional disability and early mortality. Moreover, health deterioration dramatically increases the financial cost of social and health care system. Thus, how to treat depression, diabetes, and diabetes complicated by depression has become one of the world’s urgent concerns. The activation of nod-like receptor family pyrin domain containing 3 (NLRP3) is closely related to mental illness. This finding provides a new perspective for studying depression. NLRP3 plays an important role in the development of diabetes. In this review, we elaborate the definition and epidemiology of depression, diabetes, and diabetic depression and introduce the functional characteristics of an NLRP3 inflammasome and upstream P2X7 receptor. Moreover, related research on NLRP3 inflammasomes and P2X7 receptors is summarized and used as a reference for confirming that the excessive activation of P2X7- NLRP3 leads to the increased release of inflammatory cytokines, such as IL-1β, in depression and diabetes. We provide insights into the P2X7–NLRP3–IL-1β pathway as an important pathological mechanism and novel therapeutic target in diabetes and depression. Given that the P2X7–NLRP3–IL-1β pathway may play an important role in diabetes confounded by comorbid depression, the possibility of intervention with baicalin is proposed.

Paclitaxel (PTX) is widely used as a radiosensitizer in the clinical treatment of cancer. However, the efficacy of chemoradiotherapy is limited by the hostility of the tumor microenvironment such as hypoxia. To overcome this constraint, we designed pleiotropic radiotherapy sensitized liposomes containing perfluorotributylamine (PFTBA) and PTX. The results showed that liposomes significantly accumulated in the tumor site. PFTBA in liposomes dramatically reversed tumor hypoxia and improved the sensitivity of tumor radiotherapy. PTX in liposomes blocked the cell cycle of tumor cells in the radiation-sensitive G2/M phase, which was even greater when combined with PFTBA. In vitro and in vivo tumor treatment further demonstrated remarkably improved therapeutic outcomes in radiotherapy with such biocompatible liposomes. In conclusion, the pleiotropic liposomes encapsulated PFTBA and PTX provide significant radiotherapy sensitization and show promise for future application in clinical medicine.