Effect of Panaxtriol Saponins on synaptophysin and postsynaptic density-95 expression at different periods of cerebral infarction

BACKGROUND： The change in expression of synaptophysin （Syp） and postsynaptic density-95 （PSD-95） alters after cerebral infarction, and the plasticity of synapses contributes greatly to nerve function recovery. Chinese medicinal substances may play an important role in the expression of Syp and PSD-95. OBJECTIVE： To observe the effect of Panaxtriol Saponins （PTS）, an active component in Sanqi tongshu capsules, on the expression of Syp and PSD-95 after cerebral infarction at different time points in rats, so as to examine the cerebral function remodeling mechanism. DESIGN, TIME AND SETTING： A randomized and controlled observation which was performed in Dongzhimen Hospital, Beijing University of Traditional Chinese Medicine from January to March, 2007. MATERIALS： Twenty-six healthy male Sprague Dawley rats were used to establish middle cerebral artery occlusion based on the Longa method. Sanqi tongshu capsules （containing 100 mg PTS per tablet） were provided by the Chengdu Huashen Group and nimodipine tablets （30 mg） by Tianjin Zhongyang Pharmaceutical Co., Ltd. METHODS： Twenty-six rats were randomly divided into an operation group （n = 21 ） and a control group （n = 5）. The operation group underwent the EZ Longa procedure to make the middle cerebral artery occlusion model. After surgery rats were randomly divided into a model group, a PTS group and a nimodipine group, with seven rats in each group. Rats were intragastrically administrated with saline （2 mL/d） in the model group, with Sanqi tongshu capsule （5.4 mg/100 g/d） in the PTS group, and with nimodipine （1.73 mg/100 g/d） in the nimodipine group. Rats in the control group did not undergo model establishment and drug administration. MAIN OUTCOME MEASURES： The expressions of Syp and PSD-95 were measured by immunohistochemical and image analysis at days 3, 7 and 28 after the operation. RESULTS： The expression of Syp and PSD-95 in the operation group was significantly lower than in the control group at days 3, 7, 28 postoperatively （P 〈 0.05）. The expression of Syp and PSD-95 in the PTS group and nimodipine group was significantly higher than in the model group at day 28 postoperatively （P 〈 0.05-0.01）. Additionally, after PTS and nimodipine treatment at different intervals, the expression of Syp and PSD-95 at day 28 postoperatively was significantly higher than those at days 3 and 7 postoperatively, respectively （P 〈 0.01）. CONCLUSION： PTS can promote the expression of Syp and PSD-95, i.e. the remodeling process of synapses, after cerebral infarction at different time points in rats, which contributes to cerebral function remodeling.

Epidemiological and comparative genomic analyses of Multidrug- Resistant Acinetobacter baumannii collected between 2020 and 2022 in Liaocheng City, Shandong Province, China

The emergence and prevalence of multidrug-resistant Acinetobacter baumannii(MRAB)poses a huge challenge to clinical treatment.To investigate the genetic and epidemiologic characteristics of MRAB in Liaocheng,China,and to explore potential resistance mechanisms,56 MRAB strains were collected from the clinical departments of seven hospitals in Liaocheng between 2020 and 2022.Molecular typing,antimicrobial resistance patterns,and epidemiological characteristics were determined by genome sequencing and comparative genome analysis.Sequence type(ST)540 was the most prevalent ST of the 56 MRAB in Liaocheng,and most strains(92.86%)were grouped into CC92.Core genome multilocus sequence typing subdivided the strains according to the number of allelic differences and could distinguish different outbreaks caused by ST540 isolates in the hospitals.All the isolates harbored blaOXA-23 and blaADC-25,and at least 92.86%of the isolates were resistant to 10 antibiotics.The major MRAB epidemic clone detected in Liaocheng was ST540,which was different from the results reported in other regions in China.Furthermore,several inter-hospital transmissions of ST540 isolates were observed.The findings highlight the urgent need for effective nosocomial infection control measures and the continuous surveillance of ST540 MRAB in Liaocheng.