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Background: Antibiotic resistance is the main cause of Helicobacter pylori (H. pylori) treatment failure. This study aimed to explore the characteristics of antibiotic resistance of H. pylori isolates in Beijing in the last 8 years and to estimate the impact of previous eradication failure on resistance patterns. Materials and methods: This retrospective study included data from a single center in Beijing from 2013 to 2020. Antibiotic susceptibility of 365 clinical H. pylori isolates was tested for amoxicillin, clarithromycin, metronidazole, levofloxacin, moxifloxacin, and tetracycline. The characteristics of the included patients and their previous eradication history were collected. Primary and secondary resistance rates of H. pylori to the six antibiotics and the impact of previous eradication failure on antibiotic resistance patterns were analyzed. Results: The overall primary resistance rates of amoxicillin, clarithromycin, metronidazole, levofloxacin, moxifloxacin, and tetracycline were 0.7%, 55.2%, 68.0%, 49.7%, 64.5%, and 0%, with no significant increase during the observed period; while the secondary resistance rates were 3.2%, 96.7%, 90.7%, 93.1%, 80.0%, and 0%, respectively. The secondary resistance rate of clarithromycin (p <.001), metronidazole (p =.001), and levofloxacin (p <.001) significantly increased to 100% as the number of previous eradication therapies increased and exhibited a linear association. For strains naive to eradication, only 6.8% were susceptible to all the antibiotics, while 32.4% were single resistant, and 60.8% dual or multiple resistant. Clarithromycin+metronidazole+fluoroquinolone multiple resistance was the predominant pattern (0 course: 21.6%, 1 course: 37.5%, 2 courses: 56.1%, ≥3 courses: 71.1%; p <.001) for patients with treatment failure. The prevalence of dual or multiple‐resistance patterns increased significantly as the number of previous therapies increased. Conclusions: The prevalence of primary and secondary resistance rates of clarithromycin, metronidazole, moxifloxacin, and levofloxacin were high in Beijing. Multiple‐resistance patterns were common after treatment failure. Resistance rates of amoxicillin and tetracycline remained low and stable. [ABSTRACT FROM AUTHOR]

Isolated peanut protein (PPI) dispersions were pretreated by high pressure at 100, 300, and 500 MPa prior to enzymatic hydrolysis with alkaline protease (Alcalase). The degree of hydrolysis (DH) was determined by the pH‐stat method, the hydrolysates profiles were analyzed by high‐performance liquid chromatography (HPLC), the molecular weight distribution (MWD) was analyzed by gel filtration chromatogram (GFC), and content of SH/S‐S and antioxidant activity of hydrolysates were evaluated. Results showed that HP pretreatment improved effectively the enzymatic hydrolysis of PPI, with an effective sequence of 300 > 100 > 500 MPa. However, no significant differences were observed in the peak pattern of HPLC profiles, but the peak times were earlier in HPLC profiles of the HP‐treated protein. GFC analysis showed that more peptide fractions with low molecular weight appeared in the hydrolysates of the HP‐treated PPI with increasing pressure. Moreover, the level of free SH of hydrolysates of the HP‐treated PPI was relatively higher than non‐HP‐treated PPI. The hydrolysates of the HP‐treated PPI exerted higher antioxidant activity (reducing power and DPPH radical scavenging) than the hydrolysates of non‐HP‐treated PPI. The results indicated that high pressure treatment affected the enzymatic hydrolysis of peanut protein and some protein structure properties and improved antioxidant activity of PPI hydrolysates. [ABSTRACT FROM AUTHOR]

Electromotor on oil platform often has mechanical failures. In order to achieve monitoring and diagnosis of the electromotor, common diagnostic methods of electromotor are summarized first, and then vibration monitoring is regarded as a suitable method for monitoring and diagnosing of mechanical failures by comparing the advantages and disadvantages of each method and characteristics of mechanical faults. At last, the fault frequencies and arrangements of vibration measuring points are analyzed. By using vibration monitoring method, the diagnosis of bearing faults of electromotor is carried out. The results show that the analysis of condition monitoring methods for electromotor is meanning for machine maintenance and repair, and it lays foundation for computerized repair system and resource management system. [ABSTRACT FROM AUTHOR]