Objective:To understand the clinical prevalence and drug resistance of Raoultella ornithinolytica, and to analyze the drug-resistant characteristics of carbapenem-resistant strains. Methods:A total of 83 clinical isolates of R.ornithinolytica, identified using matrix-assisted laser desorption ionization time-of-flight mass spectrometry between May 2015 and December 2020, were collected. Clinical information, drug-resistant phenotype, and carbapenemase gene of the carbapenem resistant strains were analyzed. Homology of the resistant strains was examined by pulse-field gel electrophoresis (PFGE). The molecular characteristics of plasmids, drug resistance genes and virulence genes were determined by whole genome sequencing (WGS), and a phylogenetic tree was constructed based on core single-nucleotide polymorphisms(core-SNPs) for evolutionary analysis of the carbapenem-resistant strains. Results:All 83 clinical isolates were confirmed as R.ornithinolytica, of which 11 strains were resistant to carbapenem antibiotics. The resistant strains were mainly sourced from the drainage fluid and wound secretions of patients in surgery, intensive care unit and oncology department. In addition to carbapenems resistances, the 11 strains were also resistant to cephalosporins, cephamycins, and aztreonam, while maintaining good in vitro activity to levofloxacin, tigecycline and colistin. Carbapenemase gene detection showed that 8 strains carried the bla IMP-4, 3 carried bla KPC-2, of which 1 strain carried both bla IMP-4 and bla KPC-2, and 2 strains carried both bla IMP-4 and bla NDM-1. PFGE results showed 7 banding types and 4 epidemic strains. WGS identified plasmid replicon types carried by the 11 strains of R. ornithinolyticus including IncFIA, IncFIB, IncHI1B, IncU, repB and Col, along with 10 additional types of drug resistance genes. Iron carrier related virulence genes entB, fyu, ybt and irp were detected in all carbapenem-resistant strains. Phylogenetic analysis showed that Ro6348 and Ro6050, Ro7401 and Ro7242, Ro8647 and Ro5832, and Ro9907 and Ro8856 were grouped together, while Ro8454, Ro7349 and Ro7326 were located on different branches. Conclusions:The overall drug resistance of R. ornithinolytica closely resembles Klebsiella pneumoniae and carries a variety of drug-resistant genes, but differs from domestic K.pneumoniae in that its carbapenemase is mainly IMP-4. PFGE and phylogenetic analysis results suggest that the strain has a tendency of mutual transmission in hospital, which deserves more attention.

Objective:To study the current status of longitudinal extrauterine growth restriction (EUGR) in extremely preterm infants (EPIs) and to develop a prediction model based on clinical data from multiple NICUs.Methods:From January 2017 to December 2018, EPIs admitted to 32 NICUs in North China were retrospectively studied. Their general conditions, nutritional support, complications during hospitalization and weight changes were reviewed. Weight loss between birth and discharge > 1SD was defined as longitudinal EUGR. The EPIs were assigned into longitudinal EUGR group and non-EUGR group and their nutritional support and weight changes were compared. The EPIs were randomly assigned into the training dataset and the validation dataset with a ratio of 7∶3. Univariate Cox regression analysis and multiple regression analysis were used in the training dataset to select the independent predictive factors. The best-fitting Nomogram model predicting longitudinal EUGR was established based on Akaike Information Criterion. The model was evaluated for discrimination efficacy, calibration and clinical decision curve analysis.Results:A total of 436 EPIs were included in this study, with a mean gestational age of (26.9±0.9) weeks and a birth weight of (989±171) g. The incidence of longitudinal EUGR was 82.3%(359/436). Seven variables (birth weight Z-score, weight loss, weight growth velocity, the proportion of breast milk ≥75% within 3 d before discharge, invasive mechanical ventilation ≥7 d, maternal antenatal corticosteroids use and bronchopulmonary dysplasia) were selected to establish the prediction model. The area under the receiver operating characteristic curve of the training dataset and the validation dataset were 0.870 (95% CI 0.820-0.920) and 0.879 (95% CI 0.815-0.942), suggesting good discrimination efficacy. The calibration curve indicated a good fit of the model ( P>0.05). The decision curve analysis showed positive net benefits at all thresholds. Conclusions:Currently, EPIs have a high incidence of longitudinal EUGR. The prediction model is helpful for early identification and intervention for EPIs with higher risks of longitudinal EUGR. It is necessary to expand the sample size and conduct prospective studies to optimize and validate the prediction model in the future.

Brain organoids are self-organized 3D aggregates generated by human embryonic stem cells or human induced pluripotent stem cells. Their cell type and structure are similar to embryonic human brain, which are good in vitro models for the study of neurogenetic diseases and have been widely used in the study of neurogenetic diseases. This paper will discuss the advantages and challenges of brain organoids in the modeling of genetic diseases of the nervous system.

OBJECTIVE To optimize the preparation technology of baicalin （BCN）-glycyrrhizic acid （GA） solid nanocrystals （BCN-GA-SN）， to characterize them and investigate their in vitro release characteristics. METHODS According to the compatibility ratio of classic couplet medicinals “Scutellaria baicalensis-Glycyrrhiza uralensis”， the compatibility ratio of BCN and GA was determined as 6∶1 （m/m）； BCN-GA nanosuspension was prepared by precipitation method combined with high-pressure homogenization method. The preparation technology of BCN-GA nanosuspension was optimized by using mean particle size and polydispersity index （PDI） as indexes and with types and dosage of stabilizers， stirring speed and time， high-pressure homogenization pressure and frequency as factors. The freeze-dried consolidation process of BCN-GA nanosuspension was optimized to prepare BCN-GA-SN using average particle size， PDI and redispersibility index （RDI） as indicators， with the type and dosage of freeze-dried protective agents as factors； then， the physicochemical properties and in vitro release of BCN-GA-SN were investigated. RESULTS The optimal preparation technology of BCN-GA-SN was as follows： BCN-GA nanosuspension was prepared by using 15% sodium dodecyl sulfate as a stabilizer， stirring at 1 000 r/min for 15 minutes， and homogenizing at 100 MPa for 20 times； then， BCN-GA nanosuspension was freeze-dried and solidified with 5% mannitol （corresponding to the dosage of BCN）. The average particle size of prepared BCN-GA-SN was （442.2±5.7） nm with PDI of 0.225±0.015 and RDI of 1.055± 0.013. The prepared BCN-GA-SN presented as the irregularly spherical shape with more uniform size； the drug-loading amount of BCN in the nanocrystal was （62.5±0.7）%， and that of GA was （9.4±0.2）%； the in vitro release results showed that the cumulative dissolution of BCN-GA-SN was higher than that of the physical mixture of BCN and GA. CONCLUSIONS BCN-GA-SN is prepared successfully in this study with uniform particle size and even distribution， which can effectively improve the dissolution of BCN.

ObjectiveTo investigate the effect of Zhishi Xiebai Guizhitang （ZXGT） on isoproterenol （ISO）-induced myocardial infarction （MI） in rats through the tumor necrosis factor/nuclear factor-κB （TNF/NF-κB） signaling pathway. MethodForty-eight SD rats were randomly divided into control group （blank）， model group， perindopril group （4 mg·kg^-1）， ZXGT group （24.4 g·kg^-1）， ZXGT +inhibitor group （ZXGT， 24.4 g·kg^-1， TNF-α receptor inhibitor R7050， 5 mg·kg^-1）， and an inhibitor group （R7050， 5 mg·kg^-1）， with eight rats in each group. The rats in each group were orally administered with their respective drugs for 7 days. Additionally， in the ZXGT + inhibitor group and the inhibitor group， R7050 was injected intraperitoneally at a dose of 5 mg·kg^-1 on the 6^th and 7^th days. Except for the control group， all other groups were given intraperitoneal injections of ISO for 2 consecutive days to induce MI in rats. On the 7^th day of the experiment， the rats were anesthetized 30 min after ISO injection， and their electrocardiograms （ECGs） were recorded to observe ST-segment elevation. Small animal echocardiography was used to measure global longitudinal strain （GLS） and cardiac synchrony. Blood samples were collected from the abdominal aorta to measure the levels of serum cardiac troponin T （cTnT）， creatine kinase-MB （CK-MB）， lactate dehydrogenase （LDH）， tumor necrosis factor-α （TNF-α）， and interleukin-1β （IL-1β）. Histopathological changes in myocardial tissue were observed using hematoxylin-eosin （HE） staining. Immunohistochemistry （IHC） was used to detect the expression of TNF-α， NF-κB p65， and p-NF-κB p65 proteins in myocardial tissue. Western blot was performed to measure the expression of tumor necrosis factor receptor 1 （TNFR1）， tumor necrosis factor receptor-associated factor 2 （TRAF2）， transforming growth factor-beta-activated kinase 1 （TAK1）， NF-κB inhibitory protein alpha （IκBα）， phosphorylated （p）-IκBα， NF-κB p65， and p-NF-κB p65 proteins in myocardial tissue. ResultCompared with the control group， the model group showed significant ST segment elevation on the ECG （P<0.01）， increased GLS， and reduced cardiac synchrony on echocardiography （P<0.01）. Histopathological examination revealed extensive myocardial necrosis. Furthermore， the serum levels of cTnT， CK-MB， LDH， TNF-α， and IL-1β were significantly increased （P<0.01）， and the expression levels of TNF-α， TNFR1， TRAF2， TAK1， p-IκBα， and p-NF-κB p65 proteins in myocardial tissue were significantly elevated （P<0.01）， while the expression level of IκBα was significantly decreased （P<0.01）. Compared with the model group， the perindopril group， the ZXGT group， the ZXGT + inhibitor group， and the inhibitor group rats showed a significant reduction in ST-segment elevation on the ECG （P<0.05， P<0.01）， improvement in GLS and cardiac synchrony （P<0.05， P<0.01）， a decrease in the area of myocardial necrosis， and reduced serum levels of cTnT， CK-MB， LDH， TNF-α， and IL-1β （P<0.01）. Additionally， the ZXGT group， the ZXGT + inhibitor group， and the inhibitor group downregulated the increased TNF-α， TNFR1， TRAF2， TAK1， p-IκBα， and p-NF-κB p65 protein expression levels and upregulated IκBα expression levels in the myocardial tissue （P<0.05， P<0.01）. No significant differences were observed between the ZXGT group and the ZXGT + inhibitor group or the inhibitor group. ConclusionZXGT can protect against ISO-induced myocardial injury in rats and improve cardiac function， and its mechanism of action may be related to the regulation of the TNF/NF-κB signaling pathway.

Objective To observe the value of preoperative CT enterography(CTE)for predicting the necessity of enterectomy in ovarian cancer(OC)patients for achieving optimal debulking surgery(ODS).Methods Preoperative CTE data of 49 patients with pathologically confirmed OC were retrospectively analyzed,including 13 cases received neoadjuvant chemotherapy(NACT)and 36 cases did not.The length(L)and circumference(C)of muscular involvement shown on CTE were taken as criteria for judging the necessity of enterectomy in OC patients([degree 0:no muscular involvement,degree 1:L＜3.0 cm and C＜1/3,degree 2:L≥3.0 cm[A]or C≥1/3[B]).The patients were followed up for at least 1 year after surgery,and the actual operation results were recorded to estimate the ideal surgical strategy.The consistency of CTE evaluated necessity of enterectomy and the ideal surgical strategy was analyzed.Results For patients not undergoing NACT,according to degree 2 A or B showed on CTE,predicted results had excellent agreement with the ideal surgical strategy(Kappa=0.852,P＜0.001),while those according to degree 1 or 2,2 A,2 B were all in good agreement with the ideal surgical strategy(Kappa=0.684-0.771,all P＜0.001).For patients undergoing NACT,the predicted results of degree 2 muscular involvement showed on CTE before NACT had excellent consistencies with the ideal surgical strategy(all Kappa=0.806,all P=0.003).The predicted results of degree 2 muscular involvement showed on CTE after NACT had moderate consistencies with the ideal surgical strategy(all Kappa=0.581,all P=0.021).Conclusion Preoperative CTE could be used to predict the necessity of enterectomy in OC patients for achieving ODS.

Objective To investigate the effect of Water-soluble total alkaloids of Yimucao Injection(YITA)on postpartum uterine involution.Methods A guinea pig abortion model was established by drug method.0.17 g·kg-1 YITA was intragastrically administered to record the amount of bleeding and the contents of E2 and P in serum of guinea pigs after delivery.The uterine coefficient was calculated and the contents of NO,ET-1 and Ca2+ in uterine tissue were measured.The isolated uterine model and the in vivo uterine model were prepared by guinea pigs.The former was given YITA 0.05,0.1 and 0.2 mg·mL-1,and the latter was intramuscularly injected with YITA 10,20 and 40 mg·kg-1.The changes of uterine smooth muscle(USM)contractile activity,frequency and tension were recorded by biological function test system.Results Intragastric administration of YITA could decrease the uterine coefficient(P<0.001),NO content in uterine tissue and serum P content in guinea pigs with medical abortion(P<0.01),significantly increased ET/NO ratio(P<0.001);it tended to increase Ca2+ content in uterine tissue(P<0.1).In the isolated USM test,50 and 100 mg·L-1 YITA significantly increased USM contractile activity in guinea pigs(P<0.05),and 200 mg·L-1 YITA significantly decreased USM contractile minimum in guinea pigs(P<0.05)in the in vivo USM contractile test,YITA enhanced USM contractile activity,and 40 mg·kg-1 YITA significantly increased USM contractile activity and frequency in guinea pigs(P<0.05);10 mg·kg-1 YITA significantly increased USM contractile frequency in guinea pigs(P<0.05)and tended to increase motility(P=0.0569<0.1);20 mg·kg-1 YITA tended to increase frequency(P=0.0898,0.0699 respectively,<0.1).Conclusion YITA has the effect of promoting uterine involution,and the mechanism is related to the regulation of ET/NO balance and the direct promotion of USM contraction.YITA is an effective substance for uterine contraction and hemostasis with leonurus injection in the treatment of postpartum hemorrhage and uterine involution.

Objective To explore the therapeutic effect and toxicity of Croton tiglium L.(croton)oil on rats with cold accumulation constipation,and to clarify the toxic-effect relationship of croton oil in the treatment of cold accumulation constipation.Methods The rats were orally treated with 10%2℃activated carbon solution for 3 consecutive days to replicate the model of cold constipation.The rats were fed with croton oil on the fourth day,and then the time of first defecation and the number of defecations within 3 h were observed and recorded.HE staining was used to evaluate the general pathological conditions of the colon tissues of rats.The serum levels of interleukin(IL)-6,IL-10,tumor necrosis factor(TNF)-α,cyclooxygenase(COX)-2,macrophage inflammatory protein(MIP)-1,alanine aminotransferase(ALT),aspartate aminotransferase(AST),and total protein(TP)were detected.Immunohistochemistry was used to detect the expression of myeloid differentiation factor 88(MyD88)and nuclear transcription factor(NF)-κB P65 in colon tissues of rats.Results Croton oil could shorten the time of first defecation and increase the number of defecations within 3h in rats with cold accumulation constipation to varying degrees,and the 3.78,2.83,and 1.89 g·kg-1 croton oil group had significant statistical significance(P<0.05).HE staining results showed that compared with the model group,croton oil group could cause different degrees of inflammation and focal necrosis,goblet cell loss and lamina propria edema in the colon tissue of rats,and the 3.78 g·kg-1 croton oil group was the most serious in the colon tissue injury.In addition,compared with model group,croton oil group could increase the levels of COX-2,TNF-α and IL-6 in serum to varying degrees(P<0.05),and 3.78 g·kg-1 croton oil group had the most obvious effect.The level of MIP-1 in serum was increased in croton oil group,and the effect was significant in 3.78 g·kg-1 croton oil group(P<0.01).But croton oil group had no significant effect on serum IL-10 level of rats.The immunohistochemical results showed that the protein levels of MyD88 were increased in croton oil dose groups except 0.05 dose group,and there were significant differences in 3.78,2.83,and 1.89 g·kg-1 dose groups(P<0.05).The expression level of NF-κB p65 was enhanced in the colon of rats after croton oil treatment,and there was significant difference in 3.78 g·kg-1 croton oil group(P<0.05).In addition,compared with model group,croton dose groups had no changes in organ indexes of heart,spleen,lung,kidney and thymus(P>0.05),while liver organ indexes in1.89 and 0.94 g·kg-1 croton oil groups were significantly increased(P<0.05).The results of liver biochemical indexes showed that croton oil group did not increase the contents of ALT,AST,and TP in serum of rats,and the differences were not statistically significant(P>0.05).Conclusion Croton oil can exert a dose-dependent purgative effect at 3.78,2.83,and 1.89 g·kg-1,but it also induced colonic mucosal injury in rats by regulating the inflammatory response mediated by the MyD88/NF-κB pathway.At 0.94 and 0.47 g·kg-1,croton oil almost did not cause colon tissue injury in rats,but it had a weak purgative effect at this dose,suggesting that the best concentration range of croton oil in the treatment of cold accumulation constipation may be between 0.94 and 1.89 g·kg-1.

Conjunctival melanoma (CM) is a rare and fatal malignant eye tumor. In this study, we deciphered a novel anti-CM mechanism of a natural tetracyclic compound named as cucurbitacin B (CuB). We found that CuB remarkably inhibited the proliferation of CM cells including CM-AS16, CRMM1, CRMM2 and CM2005.1, without toxicity to normal cells. CuB can also induce CM cells G2/M cell cycle arrest. RNA-seq screening identified KIF20A, a key downstream effector of FOXM1 pathway, was abolished by CuB treatment. Further target identification by activity-based protein profiling chemoproteomic approach revealed that GRP78 is a potential target of CuB. Several lines of evidence demonstrated that CuB interacted with GRP78 and bound with a K _d value of 0.11 μmol/L. Furthermore, ATPase activity evaluation showed that CuB suppressed GRP78 both in human recombinant GRP78 protein and cellular lysates. Knockdown of the GRP78 gene significantly induced the downregulation of FOXM1 and related pathway proteins including KIF20A, underlying an interesting therapeutic perspective. Finally, CuB significantly inhibited tumor progression in NCG mice without causing obvious side effects in vivo. Taken together, our current work proved that GRP78-FOXM1-KIF20A as a promising pathway for CM therapy, and the traditional medicine CuB as a candidate drug to hinder this pathway.

Objective:To explore the application of flipped classroom teaching in the standardized residency training of students in department of hepatic surgery from the perspective of production-oriented approach (POA) theory.Methods:Based on the implementation time of flipped classroom teaching (January 2017) from the perspective of POA theory in West China Hospital, 51 nursing students who were routinely trained in department of hepatic surgery before the implementation (January 2015 to January 2017) were included in the control group. After the implementation (January 2017 to January 2019), 51 nursing students under the residency training were included in the observation group. The changes of test scores, independent learning ability and professional awareness of the two groups of nursing students before and 6 months after the training were compared, and the teaching satisfaction after the training was recorded. SPSS 19.0 was performed for t test and chi-square test. Results:The total scores of the theoretical examination scores of the two groups of nursing students, the total scores of the clinical practice assessment scores, and the self-learning ability assessment scale for nursing college students (learning motivation, self-management ability, learning cooperation ability, information literacy) scores and total scores in each dimension were significantly higher than those before training, and the observation group was significantly higher than the control group ( P<0.05); the two groups of professional maturity scales (career goals, professional self-confidence, professional autonomy, professional value, dependence on relatives and friends, occupation reference) scores of all dimensions were significantly improved compared with those before the training, and the scores of the observation group (career goals, professional self-confidence, professional autonomy, professional value) were significantly higher than those of the control group during the same period ( P<0.05). There was no statistical significance in the comparison between the two groups' dependence on relatives and friends and occupational reference scores ( P>0.05); the teaching satisfaction rate of nursing students in the observation group was 96.08%, which was significantly higher than that of the control group (82.35%). Conclusion:The application of flipped classroom teaching from the perspective of POA theory in the standardized residency training of department of hepatic surgery can significantly improve the autonomous learning ability of nursing students, which is conducive to the improvement of test scores and professional awareness, with high teaching satisfaction.