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Simple Summary: Bordetella bronchiseptica (B. bronchiseptica) is a severe zoonotic pathogen widespread in aquaculture environments. However, information on the distribution and resistance of this pathogen remains scarce in pig farms. This study isolated and analyzed B. bronchiseptica from pig farms in central China and revealed a high frequency of resistance to this pathogen, with most strains forming biofilms. In addition, a B. bronchiseptica strain with a heteroresistant phenotype to gentamicin was isolated, which is a rare case and requires vigilance. This study enhances our understanding of the biological characteristics, such as the distribution and resistance, of B. bronchiseptica in pig farms in central China. This can provide valuable data for future related research and pathogen prevention and control. Bordetella bronchiseptica is a significant contributor to respiratory disease in pigs, leading to substantial economic losses in the swine industry worldwide. We isolated 52 B. bronchiseptica strains from 542 samples collected from pigs with atrophic rhinitis and bronchopneumonia in central China. Multi-locus sequence typing identified two prevalent sequence types: ST6 (69.23%) and ST7 (30.77%). PCR-based detection of seven virulence genes (fhaB, prn, cyaA, dnt, bteA, fla, and bfrZ) revealed that six of these genes were present in over 90% of the isolates, with bfrZ being the exception at 59.62%. Antimicrobial susceptibility testing, performed using the K-B method, demonstrated high sensitivity to enrofloxacin, polymyxin, and doxycycline but a notable resistance to tylosin, trimethoprim, tobramycin, ciprofloxacin, and amikacin. Remarkably, 86.54% of the isolates exhibited a multidrug-resistant phenotype. Notably, we successfully screened a strain of B. bronchiseptica with a heteroresistance phenotype to gentamicin using population analysis profiling, which is a rare case. Biofilm-formation assays indicated that 96.15% of the isolates possessed biofilm-forming capabilities. These findings provide crucial insights into the prevalence of B. bronchiseptica in central China, facilitating the development of effective preventive measures to safeguard both animal and human health. [ABSTRACT FROM AUTHOR]

[Objectives] As bolts and pins are important connector for installation of shipboard equipments,using properly simplified method for anti-shock evaluation can reduce the computation cost and improve the simulation efficiency. [Methods] On the basis of time domain analysis on the anti-shock property of shipboard equipment,a marine generator with a large amount of connectors (e.g. boltss and pins) is chosen as research object. Firstly,installation simulation of connection with bolts and pins is carried out to obtain the stiffness charcteristics in different phases of shock loading using busing unit, and equivalent dynamic model of equipment connection is attained. Then,simulation evaluation is made on the marine generator by time domain analysis,the results are compared with experimental data acquired from floating shock platform in order to verify the effectiveness and reliability of the simplified method. Lastly,criteria for failure evaluation of large-scale equipment connection under shock loading is attained.[Results] The deviation of obtained base loads as well as dynamic response between numerical values and experimental data is less than 10%,and the simplified simulation method for connection evaluation process is effective and reliable. [Conclusions] The findings in this paper can provide significant references for the evaluation of the anti-shock properties of equipment.

The increased proliferation of vascular smooth muscle cells (VSMCs) contributes to the pathogenesis of vascular diseases. The intermediate conductance calcium‐activated potassium (IKCa) channel plays a critical role in VSMC proliferation by raising the intracellular calcium concentration ([Ca2+]i), but the underlying mechanism is still not unclear. Here we investigated the cooperation between IKCa and transient receptor potential canonical 1 (TRPC1) channels in mediating extracellular Ca2+ entry, which in turn activates downstream Ca2+ signalling in the regulation of VSMC proliferation using serum‐induced cell proliferation model. Serum‐induced cell proliferation was accompanied with up‐regulation of IKCa expression and an increase in [Ca2+]i. Serum‐induced cell proliferation and increase in [Ca2+]i were suppressed by IKCa inhibition with TRAM‐34 or IKCa knockdown. Serum‐induced cell proliferation was strongly reduced by the removal of extracellular Ca2+ with EGTA or intracellular Ca2+ with BAPTA‐AM and, additionally, by TRPC1 knockdown. Moreover, the increase in [Ca2+]i induced by serum or by IKCa activation with 1‐EBIO was attenuated by TRPC1 knockdown. Finally, serum induced ERK1/2 activation, which was attenuated by treatment with TRAM‐34 or BAPTA‐AM, as well as TRPC1 knockdown. Consistently, serum‐induced cell proliferation was suppressed by ERK1/2 inhibition with PD98059. Taken together, these results suggest that the IKCa and TRPC1 channels cooperate in mediating Ca2+ influx that activates the ERK1/2 pathway to promote cell proliferation, thus providing new mechanistic insights into VSMC proliferation. [ABSTRACT FROM AUTHOR]