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Flexible debris flow barriers are important engineering measures to prevent debris flow disasters. The existing prevention structures are mainly in the form of closed barriers, which are prone to blockage with poor regulation abilities. Therefore, we proposed open flexible debris flow barriers to overcome the above shortcomings. Based on theoretical analyses and physical model tests, the research on the regulation performance of the open flexible debris flow barriers was carried out, and the theoretical formulas for the velocity attenuation rate, run-up height, and blocking rate of debris flows were deduced. The results show that compared with the closed flexible debris flow barriers, the improved structure has a good self-cleaning effect and can effectively control the peak velocity of debris flows. The calculation results through the derived non-dimensional theoretical formulas are in good agreement with the physical test results. The velocity attenuation rate, run-up height, and blocking rate of debris flows are mainly controlled by the relative open height, dimensionless flow depth, relative density of debris flows, and the Froude number. The velocity attenuation rate and blocking rate are negatively correlated with the relative open height, and positively correlated with the relative density of debris flows. The run-up height is negatively correlated with both the relative open height and the relative density. The above research can provide theoretical and technical support for the application of open flexible barriers in debris flow prevention and control projects.

Antibiotic residues in milk powder are public focusing concerns relevant to food safety. Long term exposure to antibiotic residues will lead to drug resistant strains in human body, reduce body's immunity, and bring health hazards to consumers. Sulfonamides, (fluoro)quinolones and macrolides are high frequency detecting antibiotic residues in matrix of milk powder. Rapid screening analysis of these residues and simultaneous confirmation with high confidence are valuable in practical scenarios of investigation testing, special monitoring program and so on. The direct analysis in real time (DART) ion source is an emerging technology of ambient pressure desorption ionization, it can directly complete the analysis of sample ionization and injection at the ambient pressure and open experimental environment, without changing the properties of the analyte itself. It became possible to analyze samples directly with minimal sample preparation steps or even without any sample pretreatment procedure with DART ion source. A hybrid high resolution mass spectrotmety, quadrupole orbitrap high resolution mass spectrometry (Q-Orbitrap HRMS) is a powerful tool in veterinary drug residue analysis with superior specificity, accuracy and sensitivity. In present study, DART ion source was hyphenated to Q-Orbitrap HRMS to perform rapid screening analysis and simultaneously unambiguous identification of the above mentioned antibiotic residues in milk powder. Sample was diluted in water and fast purified by filtering solid phase extraction column and then the filtrate was subjected to DART QOrbitrap HRMS analysis. Several key parameters of the DART ion source, such as ionization type and temperature, as well as injection speed of DART ion source were optimized to enhance the performance of the method. Then, a QuickStrip (QS) Module was selected with the helium as carrier gas and ionization temperature as well as injection speed were set to 400 ℃ and 1 mm/s, respectively. The DART ion source with optimized settings coupled to Q-Orbitrap HRMS was finally applied to screening analysis. Results showed that 16 commonencountered antibiotic residues including sulfonamides, (fluoro)quinolones and macrolides can be effectively detected with the screening concentration of 100 μg/kg. Recoveries of the analytes ranged from 72.5% to 106.7% and the false negative rates were all less than 5%. Real life sample analysis was finally conducted by the proposed method with an expected method performance, evidencing the potency of the developed method in risk monitoring in milk powder for veterinary drug screening analysis. It should be mentioned here that the screening concentration of 100 μg/kg is a compromised concentration for the sake of some less sensitive analytes to provide reliable determination of the antibiotic residues with the proposed procedures. It is, however, quite meaningful concentration to indicate the existence of high risk level of corresponding antibiotic residues which need to take actions. In total, the proposed method can play a role in risk monitoring laboratories and relevant industry institutions.

The rise of antibiotic resistance poses a significant public health crisis, particularly due to limited antimicrobial options for the treatment of infections with Gram‐negative pathogens. Here, an antimicrobial peptide (AMP) SR25 is characterized, which effectively kills both Gram‐negative and Gram‐positive bacteria through a unique dual‐targeting mechanism without detectable resistance. Meanwhile, an SR25‐functionalized hydrogel is developed for the efficient treatment of infected diabetic wounds. SR25 is obtained through genome mining from an uncultured bovine enteric actinomycete named Nonomuraea Jilinensis sp. nov. Investigations reveal that SR25 has two independent cellular targets, disrupting bacterial membrane integrity and restraining the activity of succinate:quinone oxidoreductase (SQR). In a diabetic mice wound infection model, the SR25‐incorporated hydrogel exhibits high efficacy against mixed infections of Escherichia coli (E. coli) and methicillin‐resistant Staphylococcus aureus (MRSA), accelerating wound healing. Overall, these findings demonstrate the therapeutic potential of SR25 and highlight the value of mining drugs with multiple mechanisms from uncultured animal commensals for combating challenging bacterial pathogens. [ABSTRACT FROM AUTHOR]

Coronarin E is a main diterpene ever isolated from Hedychium yunnanense. With the aim to enlarge its potential application, four butenolide derivatives (compounds 4a, 4b, 5a and 5b) were obtained from coronarin E via synthetic method, and their antibacterial effects were also evaluated. It is noteworthy that compounds 5a and 5b exhibited stronger antibacterial activities against most of the tested bacterial strains than ampicillin and kanamycin, two first- and second-line antimicrobials in clinical. For example, minimum inhibitory concentration (MIC) of 5a, 5b, ampicillin and kanamycin against Acinetobacter baumanii were 2, 1, 8 and 4 μg/mL, respectively, and MIC of the four compounds mentioned above against Klebsiella pneumonia were 1, 0.5, 16 and 4 μg/mL, respectively. The current studies not only enrich the structural diversity of diterpenes derived from Hedychium genus, but also provide potent candidates for the development of antibacterial medicines. [ABSTRACT FROM AUTHOR]

Colletotrin A (1), a new 1,4-benzoxazine derivative, and eight known compounds, including two alkaloids (2-3), one acylamide (4), one benzaldehyde (5), and four sterols (6-9) were obtained from endophytic fungus Colletotrichum gloeosporioides B-142, which was isolated from Dracaena cochinchinensis. Among them, 1,2,3,4-tetrahydroquinoline-4,8-diol (2) was reported for the first time as natural product. The structure of compound 1 was elucidated with help of spectroscopic data including IR, UV, electronic circular dichroism (ECD) calculation, HRESIMS, 1D and 2D NMR (COSY, HSQC and HMBC). The antimicrobial activities were evaluated by disc diffusion method. [ABSTRACT FROM AUTHOR]

This study aimed to compare the current Essen rabies post-exposure immunization schedule (0-3-7-14-28) in China and the simple 4-dose schedule (0-3-7-14) newly recommended by the World Health Organization in terms of their safety, efficacy, and protection. Mice were vaccinated according to different immunization schedules, and blood was collected for detection of rabies virus neutralizing antibodies (RVNAs) on days 14, 21, 28, 35, and 120 after the first immunization. Additionally, different groups of mice were injected with lethal doses of the CVS-11 virus on day 0, subjected to different rabies immunization schedules, and assessed for morbidity and death status. In a clinical trial, 185 rabies-exposed individuals were selected for post-exposure vaccination according to the Essen schedule, and blood was collected for RVNAs detection on days 28 and 42 after the first immunization. A statistically significant difference in RVNAs between mice in the Essen and 0-3-7-14 schedule groups was observed on the 35th day (P < 0.05). The groups 0-3-7-14, 0-3-7-21, and 0-3-7-28 showed no statistically significant difference (P > 0.05) in RVNAs levels at any time point. The post-exposure immune protective test showed that the survival rate of mice in the control group was 20%, whereas that in the immunization groups was 40%. In the clinical trial, the RVNAs positive conversion rates on days 28 (14 days after 4 doses) and 42 (14 days after 5 doses) were both 100%, and no significant difference in RVNAs levels was observed (P > 0.05). The simple 4-dose schedule can produce sufficient RVNAs levels, with no significant effect of a delayed fourth vaccine dose (14–28 d) on the immunization potential. [ABSTRACT FROM AUTHOR]

Patients with Philadelphia chromosome‐like acute lymphoblastic leukaemia (Ph‐like ALL) often face a grim prognosis, with PDGFRB gene fusions being commonly detected in this subgroup. Our study has unveiled a newfound fusion gene, TERF2::PDGFRB, and we have found that patients carrying this fusion gene exhibit sensitivity to dasatinib. Ba/F3 cells harbouring the TERF2::PDGFRB fusion display IL‐3‐independent cell proliferation through activation of the p‐PDGFRB and p‐STAT5 signalling pathways. These cells exhibit reduced apoptosis and demonstrate sensitivity to imatinib in vitro. When transfused into mice, Ba/F3 cells with the TERF2::PDGFRB fusion gene induce tumorigenesis and a shortened lifespan in cell‐derived graft models, but this outcome can be improved with imatinib treatment. In summary, we have identified the novel TERF2::PDGFRB fusion gene, which exhibits oncogenic potential both in vitro and in vivo, making it a potential therapeutic target for tyrosine kinase inhibitors (TKIs). [ABSTRACT FROM AUTHOR]

Purpose: To characterize the cytokine profile of patients with severe fever with thrombocytopenia syndrome (SFTS) in relation to disease severity.Patients and Methods: 60 laboratory-confirmed SFTS patients and 12 healthy individuals from multi-centers in Shandong Province of China were included, and all patients were divided into fatal patients (9) and recovered patients (51) due to their final outcomes. Multiplex-microbead immunoassays were conducted to estimate levels of 27 cytokines in the sera of patients and controls.Results: The results showed that levels of IL-2, IL-4, IL-6, IL-7, IL-8, IL-15, IL-1RA, G-CSF, GM-CSF, IFN-γ, TNF-α, basic FGF, PDGF-BB, RANTES, IP-10, MIP-1α, MIP-1β, MCP-1, and Eotaxin differed significantly among the SFTS fatal patients, recovered patients, and the healthy controls (all p< 0.05). Compared to the healthy controls, the fatal patients and recovered patients had reduced levels of IL-2, IL-4, IL-7, PDGF-BB, RANTES, and Eotaxin, while the levels of PDGF-BB and RANTES were significantly lower in fatal patients compared to recovered patients. The increasing levels of IL-6, IL-8, IL-15, IL-1RA, G-CSF, GM-CSF, IFN-γ, TNF-α, basic FGF, IP-10, MIP-1α, MIP-1β, and MCP-1 were observed in fatal patients (all p< 0.05), and the levels of IL-6, IP-10, MIP-1α, and MCP-1 were significantly higher than other two groups. The Spearman correlation analysis indicated a positive correlation between platelet count and PDGF-BB levels (p< 0.05), while the white blood cell count had a negative correlation with MIP-1 level (p< 0.05).Conclusion: The research exhibited that the SFTS virus (SFTSV) caused an atypical manifestation of cytokines. The levels of IL-6, IP-10, MIP-1α, and MCP-1 had been observed a positive association with the severity of the illness. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to develop and validate a scoring system for predicting the need for esophagogastroduodenoscopy (EGD) in clinical practice to enhance accuracy and reduce misapplications. Methods: From February 2021 to April 2022, outpatients scheduled for EGD at the Department of Gastroenterology in our hospital were recruited. Patients completed the system evaluation by providing clinical symptoms, relevant medical history, and endoscopic findings. Patients were randomly divided into the training and validation cohorts (at 2:1 ratio). The optimal algorithm was selected from five alternatives including a parallel test. Six physicians participated in a human‐computer comparative validation. Sensitivity and negative likelihood ratio (−LR) were used as the primary indicators. Results: Altogether 865 patients were enrolled, with 578 in the training cohort and 287 in the validation cohort. The scoring system comprised 21 variables, including age, 13 typical clinical symptoms, and seven medical history variables. The parallel test was selected as the final algorithm. Positive EGD findings were reported in 54.5% of the training cohort and 62.7% of the validation cohort. The scoring system demonstrated a sensitivity of 79.0% in the training cohort and 83.9% in the validation cohort, with −LR being 0.627 and 0.615, respectively. Compared to physicians, the scoring system exhibited higher sensitivity (84.0% vs 68.7%, P = 0.02) and a lower −LR (1.11 vs 2.41, P = 0.439). Conclusions: We developed a scoring system to predict the necessity of EGD using a parallel test algorithm, which was user‐friendly and effective, as evidenced by single‐center validation. [ABSTRACT FROM AUTHOR]