Objective To analyze the expression feature and function of microRNAs in exosomes secreted by leukemia cells (LCEX). Methods The mice leukemia cell line L1210 was taken as the example, and LCEXL1210 was obtained by isolating supernate of L1210 cells through density gradient centrifugation. MicroRNAs isolated from LCEXL1210 were analyzed by microarray analysis, compared with miRNA from L1210 cell line, and then some of miRNAs with different expression were verified by real-time PCR and were analyzed by Gene Ontology (GO) database. Results The number of miRNAs identified in LCEXL1210 was 1 044, and that in L1210 cell line was 872. The number of shared miRNAs between LCEXL1210 and L1210 cell line was 732, accounting for 70.1 % of LCEXL1210 and 83.9 % of L1210 cell line, respectively, which indicated that 70 % of LCEXL1210 was derived from the parental cells. Interestingly, 312 miRNAs in LCEXL1210 were found to be underrepresented in the parental cells, indicating their specificity in LCEXL1210. Some miRNAs were significantly highly expressed in LCEXL1210 compared with those in L1210 cell line, including miR-16-1, miR-210, miR-195 and so on, which showed that miRNAs isolated from LCEXL1210 were differentially expressed with those from the parental cells. Some differentially expressed miRNAs from LCEXL1210 were verified by real-time PCR, and then were analyzed by GO database, which demonstrated that these highly expressed miRNAs participated in the processes of various biological function and signal transduction. Conclusions MiRNAs isolated from LCEXL1210 show a high similarity to miRNAs isolated from L1210 cells, whereas of which one-third are specific. The highly expressed miRNAs participate in the processes of various biological function and signal transduction.

Objective:To preliminarily study the characteristics of ventricular synchronicity in patients of idiopathic pulmonary arterial hypertension (IPAH) with different heart function.
Methods:Our research included in 2 groups:IPAH group, n=40 patients intermittently collected in our hospital from 2010-10 to 2014-12 and Control group, n=23 normal subjects from the same period of time. Tissue Doppler echocardiography was conducted to compare interventricular systolic and diastolic time to peak (Ts and Te), their differences (Te-Ts) and (Te-Ts) of left ventricle (LV), right ventricle (RV), interventricular septum (IVS) between 2 groups.
Results:Ts and Te of RV were longer than Ts and Te of LV and IVS in both groups, P<0.05. Compared with Control group, by heart function reducing, IPAH group showed different Ts and Te of LV and IVS, P<0.05 and Ts was gradually prolonged, Te was gradually shorter;while Te of RV became longer firs tand then became shorter thereafter. In IPAH group, the patients with heart function grade IV had the longer Ts of LV and IVS than those with heart functionII, III;the patients with heart function IV had the shorter Te of LV, RV and IVS than those with heart function II, III, all P<0.05. In IPAH group with different heart function, Te between RV-IVS and RV-LV were different from Control group, all P<0.05;Te between LV-IVS in heart function IV patients had the largest difference from Control group, P<0.05. Compared with Control group, IPAH group had gradually decreased Te-Ts of LV and IVS by heart function reducing asgrade II>III>IV, all differences had statistic meaning.
Conclusion:IPAH patients with different right heart function may have interventricular systolic and diastolic de-synchronicity;by reduced heart function, interventricular Te-Ts could be specifically shortened.

Objective To explore the expression of miRNA-181a (miR-181a) in patients with multiple myeloma (MM) and its effect on biological features of MM cells. Methods CD138+cells of bone marrow from 25 MM patients and 10 patients with hematological non-malignancies were purified by using immunomagnetic separation, and the expression of miR-181a in CD138+cells and MM cell lines including RPMI 8226, H929 and U266 were detected by real-time quantitative PCR. The effects of down-regulation and up-regulation of miR-181a expression on the biological characteristics of MM cells were studied with miR-181a antagomir and agomir. Results Compared with patients with hematological non-malignant diseases, the expression of miR-181a in CD138+ cells was upregulated in MM patients. Compared with CD138+ cells in hematological non-malignancies, high expressions of miR-181a were observed in RPMI 8226 and U266 myeloma cell line, while low expressions of miR-181a were observed in H929 cells. Down-regulation of miR-181a with 100 nmol/L miR-181a antagomir could inhibit the proliferation of U266 cells at 24,48 and 72 h [(67.1 ± 3.3) %vs. (50.5 ± 4.1) %, (71.5 ± 3.6) % vs. (52.3 ± 2.2) %, (78.1 ± 5.4) % vs. (69.5 ± 4.3) %, P < 0.05 respectively], whereas up-regulation of miR-181a with 100 nmol/L miR-181a agomir could significantly promote the proliferation of H929 cells at 24 h and 48 h [(21.2 ± 2.4) %vs. (38.5 ± 3.6) %, ( 61.3 ± 5.4) %vs. (82.2 ±6.9)%, P<0.01 respectively]. Cell cycle analysis showed that miR-181a antagomir made U266 cell cycle arrest in the G0/G1 phase. Meanwhile, susceptibility test results indicated that the apoptosis of U266 cells induced by doxorubicin, paclitaxel and 5-fluorouracil was increased when the proliferation of miR-181a expression was down-regulated with miR-181a antagomir. In migration assay, the data showed that down-regulation of miR-181a with miR-181a antagomir could inhibit the migration of U266 cells, and the proportion of migrated cells in the experimental group (62 ± 10) %was lower than that in the control group (89 ± 12) %(P< 0.05), whereas up-regulation of miR-181a with miR-181a agomir could improve the migration of H929 cells, and the proportion of migrated cells in the experimental group (242 ± 9) % was higher than that in the control group (98 ± 8)%(P<0.01). Conclusions The high expression of miR-181a expressed highly by MM cells may promote the proliferation, migration and drug resistance of myeloma cells, indicating that miR-181a could be an important prognostic biomarker candidate, and the application of gene silencing may improve the prognosis of MM.

Objective:To study the effect of micro-course teaching combined with teacher standardized patient combined with objective structured clinical examination (TSP/OSCE) on clinical practice teaching of pediatric nursing.Methods:Forty nurses who performed clinical practice in Pediatrics Department from February 2019 to July 2019 were selected as the control group, and traditional teaching was adopted in the group. In addition, 42 nurses who performed clinical practice in Pediatrics Department from August 2019 to January 2020 were selected as the research group, and the micro-course teaching combined with TSP/OSCE mode teaching was adopted in the group. Two groups of nurses' theoretical and practical skills assessment results were analyzed, and a questionnaire survey was conducted to assess nurses' satisfaction with the teaching of pediatric nursing clinical practice training mode. SPSS 22.0 was used for t test and chi-square test. Results:The research group nurses' theoretical and practical skills assessment scores were better than those of the control group, and the difference was statistically significant ( P=0.000).The nurses in the research group were more satisfied than those in the control group with such eight aspects as improving practical skills, emergency response capabilities, humanistic care and service capabilities, communication skills, and stimulating their interest in nursing learning. There were statistically significant differences ( P<0.05). Conclusion:The use of micro-teaching combined with TSP/OSCE mode in the clinical practice teaching of pediatric nursing can improve nurses' clinical practice ability and increase nurses' satisfaction in pediatric training.

Objective:To establish a conditional knockout mouse model of polycystic kidney disease 1 ( Pkd1) gene based on CRISPR/Cas9 and Cre-loxP gene editing technology, and to provide an animal model for in-depth research on the role of Pkd1 gene in the development of polycystic kidney disease. Methods:In-Fusion technology was used to construct a targeting vector. Corresponding gRNAs, Cas9 mRNAs, and donor vectors carrying the loxP site were prepared based on the Pkd1 gene, and injected into the fertilized eggs of C57BL/6N mice. The fertilized eggs were transferred to the fallopian tubes of female mice with pseudopregnancy. After the newborn mice were identified by PCR and sequencing analysis, Pkd1 flox/flox F0 generation positive mice were selected. The F0 generation positive mice were bred with wild-type mice, and F1 generation heterozygous mice with Pkd1 flox/+ genotype were selected for offspring. F2 generation homozygous mice with Pkd1 flox/flox genotype were obtained through internal expansion, and then hybridized with Cre positive Ggt1/ Cre mice. F3 generation mice with Pkd1 flox/+Ggt1 Cre genotype were obtained. F4 generation mice with Pkd1 flox/flox Ggt1 Cre genotype were obtained by self crossing or backcrossing with F2 generation Pkd1 flox/flox, namely kidney-specific Pkd1 gene knockout mice ( Ggt1-cKO mice). PCR method was used to identify the genotype of mice, and then the mice were divided into wild-type control (WT) group ( n=6), Pkd1 homozygous control (PKD) group ( n=6), and Ggt1-cKO knockout validation (CKO) group ( n=6) according to the gene identification results. Real-time fluorescence quantitative PCR (RT-qPCR) was used to detect the expression of Pkd1 mRNA in the kidneys and other organs of mice in each group. HE staining was used to detect the pathological changes in renal tissues of mice in each group. The automatic biochemical detector was used to detect the blood urea nitrogen and serum creatinine levels of mice, and the kidney coefficient was calculated. Results:The PCR detection results showed that the genotype of offspring mice in CKO group was consistent with Pkd1floxflox Ggt1 Cre. Pkd1 gene was only specifically expressed in the kidney, but not in other tissues. The RT-qPCR results showed that the relative expression of Pkd1 mRNA in the renal medulla of CKO group was significantly lower than that of WT and PKD groups. The kidney volume of the CKO group had increased by about twice compared to the WT group. Under the microscope, it could be observed that there were multiple vacuoles of varying sizes and shapes in the kidneys of the CKO group, and there was a significant increase in the interstitial space of the medullary tissue. The kidney coefficient, blood urea nitrogen, and serum creatinine in the CKO group were significantly higher than those in the WT and PKD groups (all P<0.05). Conclusion:Based on CRISPR/Cas9 and Cre-loxP gene editing technology, Pkd1 gene kidney conditional knockout mice can be successfully constructed, providing an animal model for further studying the action mechanism of Pkd1 gene in polycystic kidney disease.

Objective: To explore the mediating role of psychological and physical aggression in the association between maternal emotional symptoms with emotional and behavioral problems in preschool children, so as to provide references for effective intervention of risk factors related to childrens emotional and behavioral problems. Methods: A longitudinal study was conducted to select 12 kindergarten children and their mothers in Wuhu City, Anhui Province by using stratified clustering sampling. The baseline survey was carried out in June 2021, followed up every six months, and a total of 3 followups were administered. Totally 853 valid questionnaires of junior class children were included by the survey data from baseline, second and thirl followups. The Depression Anxiety and Stress Scale-21 (DASS-21), the Parent-Child Conflict Tactics Scales (CTSPC) and the Strength and Difficulties Questionnaire (SDQ) were used to measure maternal emotional symptoms, psychological and physical aggression, and childrens emotional and behavioral problems, respectively. Results: The physical aggression of mothers towards children in boys was higher than in girls (t=3.53, P<0.05). The results of correlation analysis showed that maternal depressive symptoms were positively correlated with psychological aggression, physical aggression and childrens SDQ scores (r=0.20, 0.21, 0.18, P<0.01), maternal anxiety symptoms were positively correlated with psychological aggression, physical aggression and childrens SDQ scores (r=0.24, 0.22, 0.10, P<0.01), respectively; maternal stress symptoms were positively correlated with psychological aggression, physical aggression. The SDQ scores were positively correlated (r=0.26, 0.25, 0.18, P<0.01), and the scores of maternal psychological aggression and physical aggression were positively correlated with the SDQ scores of children (r=0.12, 0.16, P<0.01). The mediating analysis showed that after controlling for related confounding factors, psychological aggression played a partial mediating effect in the association between maternal depressive symptoms and childrens emotional and behavioral problems, and the mediating effect ratio was 8.05%. Physical aggression played a partial mediating effect in the association between maternal depression, anxiety and stress symptoms and childrens emotional and behavioral problems, which were 15.94%, 11.73% and 12.54% (P<0.05), respectively. Conclusions Psychological and physical aggression play mediating roles in the association between maternal emotional symptoms and childrens emotional and behavioral problems, and actively improving maternal emotional symptoms and their childrens discipline methods can help reduce the occurrence of emotional and behavioral problems in preschool children.

Objective:To explore the regulatory effects of cow milk with the addition of breast milk equivalent dose of somatostatin (SST) and motilin (MTL) on food allergy and food intolerance.Methods:Young Brown Norway (BN) rats were divided into 5 groups and fed with pure breast milk(breast milk group), cow milk(cow milk group), cow milk added with SST(SST group), cow milk added with MTL(MTL group) and cow milk added with both SST+ MTL(SST+ MTL group). Allergic irritation was enhanced with skin smear at the same time.Clinical damages were quantified weekly.Levels of serous total Immunoglobulin E (IgE) and fecal calprotectin (FC) were detected by the enzyme-linked immunosorbent assay (ELISA). Gastric emptying ratio and intestinal propulsion ratio were measured by method of dextran blue.Results:In breast milk group, cow milk group, SST group, MTL group and SST + MTL group, the levels of IgE were (45.75±5.05) μg/L, (580.42±45.24) μg/L, (290.38±22.88) μg/L, (424.26±22.17) μg/L, (209.49±17.59) μg/L, respectively; FC level were (149.07±24.78) μg/g, (458.85±33.81) μg/g, (343.63±34.97) μg/g, (407.79±29.62) μg/g, (296.83±28.77) μg/g, respectively; the total score of clinical damage were (0.50±0.61) scores, (9.37±1.04) scores, (6.83±1.49) scores, (7.00±1.14) scores, (5.37±1.19) scores, respectively.The cow milk group had the highest scores of clinical damages.Compared with the cow milk group, the clinical damage score, IgE and FC of the SST, MTL and SST+ MTL groups had significantly lower levels, and there was significant difference among them (all P<0.01). The general status of the SST + MTL group was most similar to the breast milk group.The gastric emptying rate of MTL group was the closest to that of breast milk group [(92.52±6.27)% vs.(100.00±9.70)%, P<0.05]. There were obvious diarrhea and fast small intestinal propulsion in cow milk group, the small intestinal propulsion ratio in breast milk group was (39.32±2.61)%, and (71.96±4.43) % in cow milk group, the difference was statistically significant between the 2 groups ( P<0.01). The intestinal motility of SST+ MTL group was decreased, but it just prevented diarrhea caused by milk allergy, the small intestine propulsion ratio in SST+ MTL group was (38.90±2.65)% vs.breast milk group (39.32±2.61)%( P>0.05). Conclusions:The cow milk added with SST and MTL decreased allergic reaction and increased food tolerance in gastrointestinal tract, which was more similar to breast milk.SST was beneficial to relieving allergic immune reaction, MTL contributed to improving the gastrointestinal tolerance of cow milk.The combination of SST and MTL may achieve an antagonistic and balanced mechanism on gastrointestinal regulation, which could synergistically improve the gastrointestinal tolerance of cow milk.

Objective To analyze and evaluate the items of the QLICD-CPHD(V2.0)scale for chronic pulmonary heart disease using classical test theory(CTT)and item response theory(IRT).Methods 184 patients with chronic pulmonary heart disease were investigated by QLICD-CPHD(V2.0)scale.The items of the QLICD-CPHD(V2.0)scale was evaluated by some statistical methods based on CTT including correlation coefficient method,variance method,factor analysis method and Cronbach's α coefficient method.Meanwhile,Samejima hierarchical response model of item response theory was utilized to calculate the difficulty,information and differentiation coefficient content of each item in the scale.Results CTT results showed that 7 items failed meet at least three or more statistical requirements,including 6 items in the general module and 1 item in the disease specific module.IRT results showed that the range of item differentiation was 1.18～1.44,which was suitable.The difficulty coefficient increases monotonously with the increase of the difficulty level(B1→B4),and some items exceed the standard value range.The average information amount of each item ranges from 0.185～0.576.Conclusion By CTT and IRT analysis,most items of the QLICD-CPHD(V2.0)scale have good performance and good differentiation,but a few items still need further revision.

Objective:To investigate the epidemiology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in patients with maintenance hemodialysis (MHD) in Jiangsu province during SARS-CoV-2 pandemic in China from December 7, 2022 to January 27, 2023, and to analyze the influencing factors of all-cause death.Methods:It was a multi-center cross-sectional investigation. Structured questionnaire was used to collect patient information by medical staff of each hemodialysis center (room) as investigators. Part of the demography data and laboratory examination data came from the Jiangsu Province Hemodialysis Data Information System. MHD patients from hemodialysis centers (rooms) at all levels of medical institutions and independent hemodialysis institutions in Jiangsu province during the outbreak of SARS-CoV-2 infection were included, and the clinical characteristics and all-cause mortality of confirmed and suspected cases of SARS-CoV-2 infection were analyzed.Results:Questionnaire surveys and data analysis on 57 278 patients in 407 hemodialysis centers (rooms) were completed, accounting for 90.41% of the total number of MHD patients (63 357 cases) in Jiangsu province during the same period. There were 24 038 cases (41.97%) of SARS-CoV-2 infection and 14 805 cases (25.85%) of suspected infection, which were widely distributed in all dialysis centers in Jiangsu province. After clinical classification of 38 843 confirmed and suspected SARS-CoV-2 infection cases, 3 662 cases were severe and critical cases, accounting for 9.43% of the infected and suspected cases. Among the patients who had completed the questionnaires, there were 1 812 all-cause deaths, with an all-cause mortality rate of 3.16%. Multivariate logistic regression analysis showed that elderly (taking ≤50 years as a reference, 51-59 years: OR=1.583, 95% CI 1.279-1.933, P=0.001; 60-69 years: OR=3.972, 95% CI 3.271-4.858, P<0.001; 70-79 years: OR=7.236, 95% CI 5.917-8.698, P<0.001; ≥80 years: OR=11.738, 95% CI 9.459-14.663, P<0.001), male ( OR=1.371, 95% CI 1.229-1.529, P<0.001), and co-infection with hepatitis B virus (HBV) (positive serum HBV surface antigen, OR=0.629, 95% CI 0.484-0.817, P<0.001) were independent influencing factors for all cause mortality. Receiver-operating characteristic curve analysis showed that the area under the curve for male, age and current HBV infection prediction of all-cause death was 0.529 ( P<0.001), 0.724 ( P<0.001) and 0.514 ( P=0.042), respectively, and the cut-off value for age prediction of all-cause death was 65.5 years old. Compared with patients without HBV infection, MHD patients with HBV infection significantly reduced the proportion of severe and critically ill patients, all-cause hospitalizations and all cause deaths when infected with SARS-CoV-2 (4.99% vs. 6.41%, χ2=6.136, P=0.013; 8.90% vs. 11.44%, χ2=11.662, P<0.001; 2.01% vs. 3.37%, χ2=10.713, P=0.001, respectively). Conclusion:The MHD patients in Jiangsu province are susceptible to SARS-CoV-2. Elderly age and male gender are independent risk factors for death in MHD patients during the epidemic, while the HBV infection may be a protective factor for death of MHD patients infected with SARS-CoV-2.

Radiotherapy is widely used in the management of advanced colorectal cancer (CRC). However, the clinical efficacy is limited by the safe irradiated dose. Sensitizing tumor cells to radiotherapy via interrupting DNA repair is a promising approach to conquering the limitation. The BRCA1-BARD1 complex has been demonstrated to play a critical role in homologous recombination (HR) DSB repair, and its functions may be affected by HERC2 or BAP1. Accumulated evidence illustrates that the ubiquitination-deubiquitination balance is involved in these processes; however, the precise mechanism for the cross-talk among these proteins in HR repair following radiation hasn't been defined. Through activity-based profiling, we identified PT33 as an active entity for HR repair suppression. Subsequently, we revealed that BAP1 serves as a novel molecular target of PT33 via a CRISPR-based deubiquitinase screen. Mechanistically, pharmacological covalent inhibition of BAP1 with PT33 recruits HERC2 to compete with BARD1 for BRCA1 interaction, interrupting HR repair. Consequently, PT33 treatment can substantially enhance the sensitivity of CRC cells to radiotherapy in vitro and in vivo. Overall, these findings provide a mechanistic basis for PT33-induced HR suppression and may guide an effective strategy to improve therapeutic gain.