Objective:To evaluate the role of NIMA-related kinase 7 (NEK7)/Nod-like receptor family pyrin domain-containing protein 3 (NLRP3) signaling pathway in sepsis-associated encephalopathy in mice.Methods:A total of 150 healthy adult male C57BL/6 mice, aged 8-12 weeks, weighing 20-25 g, were divided into 5 groups ( n=30 each) by a random number table method: sham operation group (Sham group), sepsis group (CLP group), sepsis+ NLRP3 inhibitor MCC950 group (CLP+ MCC950 group), sepsis+ NEK7 siRNA group (CLP+ NEK7 siRNA group), and sepsis+ NC siRNA group (CLP+ NC siRNA group). Sepsis was induced by classic cecal ligation and puncture (CLP) in anesthetized animals.MCC950 10 mg/kg was intraperitoneally injected for 3 consecutive days after operation in CLP+ MCC950 group, while the equal volume of normal saline was given instead in Sham group.Immediately after operation and on 3rd day after operation, NEK7 siRNA 3 nmol/20 g was injected into the ventricle in CLP+ NEK7 siRNA group, and the equal dose of NC siRNA was injected into the ventricle instead in Sham group.The survival of mice was recorded on 4th postoperative day.On 4th and 7th days after operation, 10 mice in each group were selected for Y maze space recognition experiment.On 7th day after operation, 5 mice in each group were randomly sacrificed and hippocampal tissues were taken for determination of the contents of interleukin-1beta (IL-1β), interleukin-18 (IL-18) and tumor necrosis factor-alpha (TNF-α) (by enzyme-linked immunosorbent assay), and 6 mice in each group were sacrificed and hippocampal tissues were taken for determination of the expression of NEK7, NLRP3, cleaved-caspase-1 and apoptosis-associated speck-like protein containing a caspase-1 recruitment domain (ASC) (by Western blot). Results:The survival rates were 100%, 50%, 73%, 60% and 53% in Sham, CLP, CLP+ MCC950, CLP+ NEK7 siRNA, and CLP+ NC siRNA groups, respectively, on day 4 after surgery.Compared with Sham group, the frequency of entries into novel arm was significantly reduced, and the time spent in the novel arm was shortened at 4th and 7th days after operation, and the contents of IL-1β, IL-18 and TNF-α in hippocampus were increased, and the expression of NEK7, NLRP3, cleaved-caspase-1 and ASC was up-regulated at 7th day after operation in CLP group ( P<0.05). Compared with CLP group, the frequency of entries into novel arm was significantly increased, and the time spent in the novel arm was prolonged at 4th and 7th days after operation, and the contents of IL-1β, IL-18 and TNF-α in hippocampus were decreased at 7th day after operation in CLP+ MCC950 and CLP+ NEK7 siRNA groups, the expression of NLRP3, cleaved-caspase-1 and ASC was significantly down-regulated at 7th day after operation in CLP+ MCC950 group, the expression of NEK7, NLRP3, cleaved-caspase-1 and ASC was significantly down-regulated in CLP+ NEK7 siRNA group ( P<0.05), and no significant change was found in the parameters mentioned above in CLP+ NC siRNA group ( P>0.05). Conclusions:NEK7/NLRP3 signaling pathway is involved in SAE in mice, and the underlying mechanism may be related to promotion of inflammatory responses.

Objective:To evaluate the mechanism of short-chain fatty acids (SCFAs) reducing cognitive dysfunction in septic mice through transcriptomic analysis.Methods:Sixty SPF healthy adult male C57BL/6 mice, aged 8-12 weeks, weighing 20-25 g, were divided into 3 groups ( n=20 each) using a random number table method: sham operation group (Sham group), sepsis group (SEP group), and SCFAs+ sepsis group (SCFAs+ SEP group). Cecal ligation and puncture (CLP)was used to simulate a sepsis model in anesthetized animals. In SCFAs+ SEP group, 67.5 mmol/L acetate, 40 mmol/L butyrate, and 25.9 mmol/L propionate were added to drinking water starting from 14 days before CLP until 14 days after CLP. Y maze tests were conducted on days 4, 7 and 14 after surgery, with the number of mice in the Y maze test being the number of surviving mice on that day. On day 14 after surgery, 4 mice were selected in SEP group and SCFAs+ SEP group and sacrificed after anesthesia, and brain tissues were obtained to perform transcriptome sequencing, and enrichment analysis was performed using GO database and KEGG database. Finally, 5 mice were randomly sacrificed in each group, and brain tissues were collected and Western blot analysis was performed to verify the sequencing results. Results:Compared with Sham group, the number of times they entered the novel arm on days 4, 7 and 14 after surgery were significantly reduced, and the time spent in the novel arm was shortened in SEP group ( P<0.05). Compared with SEP group, the number of times they entered the novel arm on days 4, 7 and 14 after surgery was significantly increased, and the time spent in the novel arm was prolonged in SCFAs+ SEP group ( P<0.05). The results of transcriptomic analysis showed that 438 significantly differentially expressed genes were identified in SCFAs+ SEP group, of which the expression of 175 genes was up-regulated and the expression of 263 genes was down-regulated compared with SEP group. The expression of gamma-aminobutyric acid receptor rho-2 (GABRR2) in the brain tissues was significantly up-regulated in SEP group as compared with Sham group ( P<0.05). Compared with SEP group, the expression of GABRR2 in the brain tissue was significantly down-regulated in SCFAs+ SEP group ( P<0.05). There was no significant difference in the expression of GABRR2 in brain tissues between Sham group and SCFAs+ SEP group ( P>0.05). Conclusions:SCFAs may reduce cognitive dysfunction by down-regulating the expression of GABRR2 in septic mice.

Objective To explore the accuracy and influencing factors of contrast-enhanced spectral mammography(CESM)and MRI in the dimension measurement of breast lesions.Methods A retrospective analysis was performed on 104 patients with breast lesions who underwent CESM and MRI examinations within one week.The pathological size was used as the gold standard to com-pare the accuracy of the two measurement methods.Logistic regression analysis was used to compare the influencing factors of the measurement accuracy of CESM and MRI.Results The measured values of CESM,MRI and pathology were 1.70 cm(1.20-2.70 cm),1.65 cm(1.20-2.28 cm),1.75 cm(1.00-2.50 cm),respectively,and there were no statistically significant differences between the two measurement methods and the pathological results(P＞0.05).Bland-Altman plot analysis showed that 95.2％(99/104)of the differences in CESM fell within the consistency interval,and 93.3％(97/104)of the differences in MRI fell within the consistency interval.Logistic regression analysis showed that the independent risk factors affecting the accuracy of CESM and MRI measurement were lesion size and enhancement type.Conclusion Both CESM and MRI show good accuracy.As a potential alternative to MRI technology,CESM can be used for imaging evaluation of breast lesion size.