Objective To explore the immunosuppression effects,outcomes and clinical significance of mesenchymal stem cells (MSCs) transplantation in burn treatment by comparing the levels of WBC,C-reaction protein (CRP),interferon-γ(IFN-γ),interferon-o (TNF-α),interleukin-6 (IL-6),interleukin-10 (IL-10) between control burn models and models conducting MSCs transplantation.Methods After stripping Wharton's Jelly from the neonatal umbilical cord,MSCs was cultured and expanded.Burn models were constructed in male SD rats weighted at (200± 5) g,and randomly grouped for control and MSCs transplantation.The rats in transplantation group were injected subcutaneously with hUCMSCs (1.5× 106) at 24 h after burning.The content of WBC,CRP,IFN-γ,TNF-α,IL-6,IL-10 in blood samples at 0,1,2,3,5 and 7 d after burning were detected by enzyme-linked immunosorbent assay (ELISA).The ELISA results,the wound healing rate at 7,14,21 and 28 d,as well as wound healing time were compared and analyzed statistically by ANOVA between the two groups.Results WBC in control group increased significantly at 1 and 2 d,and CRP in control group increased substantially at 2 and 3 d.IFN-% IL-6 and IL-10 levels in serum showed increase on 5 d,and TNF-α arrived at its peak value at 7 d.By contrast,WBC,CRP,TNF-α,IL-6 and IL-10 of the MSCs transplantation group showed slightly increase after burning and the differences were convinced by statistical analysis,while IFN-γ showed little difference among the two groups.The MSCs transplantation group also showed significantly higher wound healing rate at 14,21,28 d and shorter wound healing time than that of the control.Conclusions MSCs transplantation can suppress the over-inflammatory response by significantly mediating the inflammatory cytokines as WBC,CRP,TNF-α,IL-6,IL-10 in burn.IFN-γseems not affected by MSCs transplantation.MSCs would be suitable to promote wound healing and repair in burn,which is achieved not only by differentiation and paracrine,but also by subtle immunoregulation.

AIM: To construct E. coli expression plasmid of recombinant human NDPK-A with a 6?His tag, optimize the expression condition and identify the activity of the product. METHODS: nm23-H1 was subcloned from plasmid pBVNMH1 to pQE40 which contain 6?His purification tag. The expression condition was modulated in grades to get the optimal expression. We purified protein with the Ni+-NTA affinity chromatography column, identified the immunogenicity of the product with Western blot, and measured the kinases activity with HPLC. In addition, angiogenesis inhibition activity of rhNDPK was identified by CAM. RESULTS: The sequence of nm23-H1 subclone in pQE40 was exactly correct. The expression rate of rhNDPK-A was 49 6%. Purified rhNDPK-A specially recognized the antiserum of NDPK-A. It also inhibited angiogenesis. CONCLUSION: PQE-nm23H1 containing 6?His can express target protein at high level. This purification method is simple than other methods, and the product has the same activity as natural human NDPK-A.

Objective To survey the satisfaction degree of the postgraduates in professional degree with The Joining Together of Double-Track education model in the current stage of professional degree graduate education and standardized training of residents in China. Methods According to various factors, such as the current situation of postgraduates in medical universities, we sought the opinions of relevant experts to design questionnaire. Meanwhile, to enhance the reliability of the questionnaire and the survey, we chose the postgraduates of Shengjing Hospital of China Medical University first to do the pre-survey, and according to the feedback, we adjusted part of the aspects, thus formed a formal questionnaire, which included the satisfaction with training of clinical practice ability, training of research ability, and tutors' assessment etc. Finally, the Chinese New Youth Forum online released the questionnaires, selecting the postgraduates in professional degree who were participating in, or had participated in the completion of the standardized training as the participants, which took place between March 2016 and May 2016. SPSS 16.0 was used for statistical analysis. The evaluation results of different majors were tested by Kruskal-Wallis rank sum test. Results According to the results of the survey, the aspects in the clinical resident standard-ized training that the 1000 postgraduates were more satisfied with were as follows: training time [42.8%(n=428)], training center [41.8% (n=418)], training of clinical practice ability [41.6% (n=416)], tutors [40.2%(n=402)], economic income [38.8%(n=388)], department arrangements [38.4% (n=384)], training of research ability [37.5%(n=375)]. There is a significant difference in the satisfaction degree of different pro-fessional graduate students in theJoining Together of Double-Trackeducation model (P<0.05). ConclusionThe Joining Together of Double-Track education model should be compatible with the training objectives of postgraduates in professional degree. Much more attention should be paid to the post-graduates, satisfac-tion degree with the clinical resident standardized training, as well as the requirements during the training period, improve the evaluation of graduate students' ability of scientific research, econo-mic income and so on, so as to improve the training system for the postgraduates.

Objective , To investigate the influence of blood pressure variability on cerebral infarction in older men. Methods Ambulatory blood pressure was measured in 1527 elderly men ( older than 65 yrs) with atherosclerosis. All cases were divided into 2 groups: Six hundred and seven patients with cerebral infarction ( group A)and 920 patients without cerebral infarction ( group B). Smooth curve method was used to analyze each patient's ambulatory blood pressure data and the trend of each patient's blood pressure curve was portrayed. The differences between the actual blood pressure and the blood pressure on the curve was defined as blood pressure variability,and the blood pressure variability between the 2 groups was compared. Results The systolic blood pressure variability in 24 hours in group A was significantly higher than that in group B( [8.4'±2. 2]mm Hg vs [ 8.0 ± 2. 0 ] mm Hg, P ＜ 0. 01 ), especially for the systolic blood pressure variability in daytime( [ 8. 2 ± 2. 2 ] mm Hg vs [ 7. 8 ± 2. 1 ] mm Hg, P ＜ 0. 01 ). However, the systolic blood pressure variability at night was not significantly different between the 2 groups( [ 8.9 ± 3. 9 ] mm Hg vs [ 8. 7 ± 3.7 ] mm Hg,P ＞ 0. 05 ). There were no significant difference between the diastolic blood pressure of 24 hours( [5. 5 ± 3.8 ] mm Hg vs [5.5 ± 1.5 ]mm Hg,P ＞0. 05),during daytime([5.4 ± 1.5]mm Hg vs [5.3 ± 1.4] mm Hg,P ＞0.05)and nighttime ( [ 6. 1 ± 2.7 ] mm Hg vs [ 6. 1 ± 2. 6 ] mm Hg, P ＞ 0. 05 ). Conclusion In elderly men with atherosclerosis,cerebral infarction was closely related to systolic blood pressure variability,but independent of nighttime systolic blood pressure and diastolic blood pressure variability.

Objective To investigate the epidemiology of viral infection in elderly patients to contract acute exacerbations of chronic obstructive pulmonary disease (AECOPD)in Minhang district of Shanghai from 2010 to 2012,and to study the relationships between viral infection and clinical features.Methods The elderly patients (age >70 year old)with AECOPD admitted from September 2010 to November 2012 were enrolled for study.The patients who couldn't complete lung function test were excluded.The pharyngeal swabs (PS)were taken from each patient within the first 24 h after admission.Nine respiratory viruses and their subtypes from pharyngeal swabs were detected by the nested multiplex polymerase chain reaction (PCR)method,including influenza virus A (FluA),2009 influenza A (H1N1 )virus (09FluH1 ), influenza virus B (FluB),respiratory syncytial virus A (RSVA)and B (RSVB),human coronavirus-229E (hCOV-229E),human coronavirus-NL63 (hCOV-NL63 ),human coronavirus-OC43 (hCOV-OC43 ), human coronavirus-HKU1 (hCOV-HKU1),human parainfluenza virus 1-4 (hPIV1-4),human adenovirus (hAdV),human boca virus (hBoV),human metapneumo-virus (hMPV)and human rhinovirus (hRV). According to the PCR results,all patients were divided into positive viral infection group and negative viral infection group.The relationships between viral infection and clinical features were analyzed.Results Sixty patients were eligible for study.Of them,14 patients were found to be positive for virus infection including a triple infected patient (FluB,hRV and hROV)and 46 patients were negative for virus infection.The viral pathogens detected in the positive viral group were:9 cases of hRV (15.00%),2 cases of hPIV (3.33%),2 cases of hCOV (3.33%),2 cases of FluB (3.33%)and 1 cases of RSV (1.67%).The mortality in the positive viral group was higher than that in the negative viral group.However,the other clinical characteristics between the two groups had no significant differences. Conclusions Human rhinovirus was the most common viral pathogen in elderly patients with AECOPD.Viral infection might be associated with the prognosis.However,the patients with viral infection are lack of specific clinical characteristics,therefore,the prompt diagnosis before careful study would be difficult.

The value of color Doppler flow imaging (CDFI) and intravenous contrast-enhanced ultrasound (CEUS) for assessing the transplanted liver and early diagnosing complications by examining hemodynamic changes was discussed. Seventy-five patients with orthotopic liver transplantation (OLT) underwent CDFI. The following parameters were measured: peak systolic velocity (PS), resistance index (RI) and Doppler perfusion index (DPI) of the hepatic artery (HA), time average velocity (TAV) of portal vein (PV) and velocity of hepatic vein (HV) in different stages post-operation. And 11 patients of them received CEUS. Thirty healthy subjects were enrolled as controls. The results showed that: (1) In 23 patients without obvious complications, TAV of PV within 15 days post-operation was significantly higher than in controls (P<0.05), PS and DPI of HA within 7 days postoperation were lower, but RI was higher than in controls (P<0.05); (2) When the hepatic artery thrombosis (HAT) occurred, PS and DPI of HA were obviously decreased, but TAV of PV significantly increased like a high saw-tooth wave; (3) While rejection occurred, both TAV of PV and PS of HA were decreased with the increase in RI of HA, and the triphasic wave of HV disappeared and displayed as saw-tooth wave; (4) The incidence of biliary complications in liver transplantation was in-creased when DPI was reduced; (5) Seven cases of hepatic carcinoma relapse after OLT demonstrated hyperecho in the arterial phase and hypoecho in the portal and later phase on CEUS; (6) In 2 cases of HA thrombus, there was no visualized enhancement in arterial phase of CEUS, but enhancement during the portal vein and parenchymal phase. It was concluded that the hemodynamic changes of PV, HA and HV in the transplanted liver are valuable for assessing the transplanted liver and early diagnosing complications on CDFI and CEUS.

Objective:To develop a risk prediction model for early cardiac arrest in emergency sepsis utilizing a machine learning algorithm to enhance the quality and efficiency of patient treatment.Methods:This study focused on patients with sepsis who received treatment at the emergency room of the First Medical Center of Chinese PLA General Hospital from January 1, 2020 to June 1, 2023. The basic clinical characteristics such as vital signs and laboratory results were collected. Patients who fulfilled the specified inclusion criteria were allocated randomly into a training group and a testing group with a ratio of 8:2. A CatBoost model was constructed using Python software, and the prediction efficiency of the model was assessed by calculating the area under the receiver operating characteristic curve (AUC). Furthermore, the performance of the model was compared to that of other widely employed clinical scores.Results:This study included a cohort of 2 131 patients diagnosed with sepsis, among whom 449 experienced cardiac arrest. The CatBoost model demonstrated an AUC of 0.760, surpassing other scores. Notably, the top 10 predictors in the model were identified as age, lactate, interleukin -6, oxygen saturation, albumin, N-terminal pro-B-type natriuretic peptide, potassium, sodium, creatinine, and platelets.Conclusions:The utilization of this machine learning algorithm-based prediction model offers a more precise basis for predicting cardiac arrest in emergency sepsis patients, thereby potentially improving the treatment efficacy for this disease.

For adapting to the change of modern medical model and suiting social demand of high quality dentists, this paper compares the differences of undergraduate education in stomatology between China and Russia by using the method of Bereday comparative education, trying to provide some reference for the reform of Chinese stomatology education. Curriculum arrangement in China is being constantly explored based on the Russian model. In China, courses are divided into basic medicine, clinical medicine and stomatology in three stages, making students relatively passive in learning. And the ratio of practice to lecture is far more higher in Russia than that in China. Thus, it's necessary to optimize structure and balance the distribution of stomatological curriculum in China, improve and popularize learning models such as problem -based learning (PBL) and so on, so as to promote the development of stomatology education of China to a higher level.

Objective:This paper is to propose a calibration model based on sine function which enables more choices to determine the functional relationship between the absorbance and the concentration of the tested substance.Methods:This paper uses Taylor series expansion and Levenberg-Marquardt to obtain the optimal parameters for the Sine model and then summarizes the characters of the Sine model. On the basis of these characters, this paper compares and evaluates the experimental data processed by the Sine model from four aspects: correctness, precision, linearity and correlation.Results:The generated sine function calibration model achieved deviations within ±3% of the national standard substance, precision ( CV%) less than 2%, and a linear correlation coefficient greater than 0.990 within the measurement range of 32-710 mg/L. The correlation coefficients between the sine model and other well-performing linear calibration models for 104 clinical samples were all greater than 0.990. Conclusions:The performance evaluation of the prealbumin assay kit using the sine function calibration model meets industry standards and shows good correlation with the results of clinical sample measurements. This indicates that the sine function calibration model can serve as a new calibration model for in vitro diagnostic research and clinical applications.

Objective:To investigate the effects and mechanisms of allogeneic epidermal stem cells (ESCs) on the survival of allogeneic full-thickness skin grafts in nude mice with full-thickness skin defect wounds.Methods:Experimental research methods were applied. Primary ESCs that appeared paving stone-like after being cultured for 7 d were obtained by enzymatic digestion method from one 4-week-old male BALB/c-NU nude mouse (the same strain, age, and sex below). The cells of third passage were identified by flow cytometry to positively express ESC marker CD44 and negatively express CD45, meanwhile, the positive expression of ESC markers of p63 and integrin 6α, and negative expression of CD71 were identified by immunofluorescence method. The ESCs of third passage in the logarithmic growth phase were used for the following experiments. Twenty-six nude mice were equally divided into phosphate buffered saline (PBS) group and ESCs group according to the random number table. A full-thickness skin defect wound was made on the back of each nude mouse, and then the wounds of the two groups were sprayed with equal volumes of PBS and ESCs, respectively. The wounds were transplanted with full-thickness skin grafts cut from the backs of 4 other nude mice. Each ten nude mice from the two groups were selected, the wound healing and skin survival on post surgery day (PSD) 0 (immediately), 3, 7, 14, and 21 were observed, and the survival ratio and shrinkage rate of skin grafts on PSD 3, 7, 14, and 21 were calculated (the number of sample was the number of surviving skin grafts at each time point); the blood perfusion in the skin grafts on PSD 3, 7, and 14 was detected by the laser speckle blood flow imager, and the blood flow ratio of nude mice skin grafts in ESCs group to PBS group at each time point was calculated (the number of sample was the pair number of surviving skin grafts in group pairing at each time point). The skin graft tissue of each 3 nude mice remained in the two groups were collected on PSD 7, and the mRNA expressions and protein expressions of tumor necrosis factor α (TNF-α), interleukin 8 (IL-8), IL-10, type Ⅰ collagen, type Ⅲ collagen, and matrix metalloproteinase 9 (MMP-9) in the tissue were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction and Western blotting, respectively. Data were statistically analyzed with Log-rank test, analysis of variance for repeated measurement, one-way analysis of variance, independent sample t test, and Bonferroni correction. Results:Taking the condition on PSD 0 as a reference, the wounds of nude mice in the two groups healed gradually on PSD 3, 7, 14, and 21, and the shrinkage of skin grafts was gradually obvious. Among them, the shrinkage healing of wound of nude mice in PBS group was more significant than that in ESCs group. On PSD 3, the skin graft of 1 nude mouse failed in ESCs group, while the skin graft of 3 nude mice failed in PBS group. On PSD 7, the skin graft of another nude mouse failed in PBS group. The survival ratio of skin grafts of nude mice in the two groups was similar on PSD 3, 7, 14, and 21 ( P>0.05). On PSD 3, 7, 14, and 21, the shrinkage rates of skin grafts of nude mice in ESCs group were (9.2±0.4)%, (19.7±1.2)%, (53.6±3.5)%, and (62.2±5.1)%, respectively, which was significantly lower than (11.0±0.9)%, (47.8±2.8)%, (86.1±7.1)%, and (89.7±9.0)% in PBS group ( t=5.719, 26.650, 11.940, 7.617, P<0.01). On PSD 3, 7, and 14, blood perfusion signals were observed in the skin grafts of nude mice in the two groups. The average blood perfusion ratios of the skin grafts of nude mice in ESCs group to PBS group were greater than 1, and there was no statistically significant difference in the overall comparison of 3 time points ( P>0.05). On PSD 7, compared with those of PBS group, the mRNA and protein expressions of TNF-α, IL-8, type Ⅰ collagen, and type Ⅲ collagen in the skin graft tissue of nude mice in ESCs group were significantly reduced, while the mRNA and protein expressions of IL-10 and MMP-9 in the skin graft tissue of nude mice in ESCs group were significantly increased (in mRNA comparison, t=2.823, 2.934, 2.845, 2.860, 3.877, 2.916, P<0.05). Conclusions:Allogeneic ESCs can reduce the shrinkage of allogeneic full-thickness skin grafts transplanted on full-thickness skin defect wounds in nude mice, promote the formation of new blood vessels between the skin graft and the wound, reduce inflammation and collagen protein expression, and promote the expression of MMP-9, thus improving the survival quality of skin grafts.