PurposeTo optimize the imaging parameters of clinical MRI scanner in rat pancreas imaging to improve the image quality and to provide better MRI image quality and more economical research method for imaging study of rat pancreas. Materials and Methods Twenty-four healthy male Wistar rats were randomly divided into the conventional sequence (CS) group, the adjustment sequence (AS) group and the optimization sequence (OS) group, with 8 rats in each group. The rats in the CS group were scanned with conventional parameters using a clinical MRI scanner. The principle of parameter adjustment was: parameters associated with T1WI or T2WI imaging quality (TR, TE, slice thickness, NEX, FOV and matrix) was set with four changes, and only one of the six parameters was changed in each scan, image quality was evaluated by two senior radiologists, the parameter corresponded the best image quality evaluated consistently by two radiologists were selected as the optimal imaging parameter, all the optimized parameters were set up step by step in this way which formed the imaging parameters in OS group. The pancreatic signal intensity and signal to noise ratio was compared between CS group and OS group after imaging.Results The optimized sequence parameters in clinical MRI scanner were listed below: T1WI sequence (M3D/FSPGR/15): TR 6 ms, TE 2.5 ms, slice thickness 2.0 mm, NEX 8, FOV 7 cm×7 cm, Matrix 120×120; T2WI sequence (FSE-XL/90): TR 4000 ms, TE 71 ms, slice thickness 2.0 mm, NEX 1, FOV 8 cm×8 cm, Matrix 192×160. The pancreatic SI in T1WI and T2WI sequence of the OS group were significantly higher than those in the CS group (t=5.16 and 3.80,P<0.01), while the pancreatic SNR in T1WI and T2WI sequence of the OS group were significantly higher than those in the CS group (t=5.65 and 3.26,P<0.01).Conclusion The optimized parameters can improve the imaging quality of rat pancreas MRI significantly, thus provide a reference for the related experimental study.

Objective To evaluate the sensitivity and specificity of different HbA1C cutoff points for diabetes diagnosis in high risk outpatients in Harbin.Methods A total of 2 122 high risk outpatients(male 1 032 and female 1 090)for diabetes screening in the Fourth affiliated Hospital of Harbin Medical University from April 2013 to February 2015 were included in this study, with the average age of(49.26±13.00)year. Oral glucose tolerance tests(OGTT)were conducted and HbA1C levels were examined in these patients. The sensitivity and specificity of different HbA1C cutoff points were calculated and a receiver operator characteristic(ROC)curve was then built.Results The average level of HbA1C in these subjects was(6.45±1.72)%. The prevalence of diabetes was 41.85%. The area under ROC curve(AUC)was 0.89 with the optimal cutoff point of HbA1C 6.0% and 0.68 for the highest Yonden index. The sensitivity and specificity of HbA1C 6.0% were 84.01% and 83.67% respectively. The sensitivity and specificity of HbA1C 6.5% were 62.84% and 95.92%, respectively. The AUC of HbA1C≥6.5% was 0.732. Conclusion HbA1C works well as the diagnostic standard for diabetes in high risk outpatients of Harbin city. The cutoff point of HbA1C 6.0% is suitable for screening diabetes in high risk population, and HbA1C 6.5% is appropriate for diabetes diagnosis, with high sensitivity and specificity.

OBJECTIVETo investigate the suitable transfection condition of human epidermal cells (hECs) with human epidermal growth factor (EGF) gene by adenovirus vector (Ad-hEGF) and its effects on the biological characteristics of hECs.

METHODShECs were isolated from deprecated human fresh prepuce tissue of circumcision by enzyme digestion method and then sub-cultured. hECs of the third passage were used in the following experiments. (1) Cells were divided into non-transfection group and 5, 20, 50, 100, 150, and 200 fold transfection groups according to the random number table (the same grouping method below), with 3 wells in each group. Cells in non-transfection group were not transfected with Ad-hEGF gene, while cells in the latter six groups were transfected with Ad-hEGF gene in multiplicities of infection (MOI) of 5, 20, 50, 100, 150, and 200 respectively. The morphology of the cells was observed with inverted phase contrast microscope, and expression of green fluorescent protein of the cells was observed with inverted fluorescence microscope at transfection hour (TH) 24, 48, and 72. (2) Another three batches of cells were collected, grouped, and treated as above, respectively. Then the transfection rate of Ad-hEGF gene was detected by flow cytometer (n=3), the mass concentration of EGF in culture supernatant of cells was detected by enzyme-linked immunosorbent assay (n=6), and the proliferation activity of cells was detected by cell counting kit 8 (CCK8) and microplate reader (n=6) at TH 24, 48, and 72, respectively. (3) Cells were collected and divided into non-transfection group and transfection group, with 6 wells in each group. Cells in non-transfection group were cultured with culture supernatant of cells without transfection, while cells in transfection group were cultured with culture supernatant of cells which were transfected with Ad-hEGF gene in the optimum MOI (50). CCK8 and microplate reader were used to measure the biological activity of EGF secreted by cells on culture day 1, 3, and 5. (4) Cells were collected and divided into non-transfection group and transfection group, with 12 wells in each group. Cells in non-transfection group were not transfected with Ad-hEGF gene, while cells in transfection group were transfected with Ad-hEGF gene in the optimum MOI (50). The expression levels of cytokeratin 14 (CK14) and CK19 of cells were measured by immunofluorescence staining at TH 24. (5) Cells were collected, grouped, and treated as in (4), with 6 wells in each group. At post scratch hour (PSH) 0 (immediately after scratch), 12, 24, and 48, the migration distance of cells was observed and measured with inverted phase contrast microscope. Data were processed with analysis of variance of factorial design, analysis of variance for repeated measurement, and LSD test.

RESULTS(1) At TH 24 and 48, morphology of cells in each transfection group and non-transfection group were similar. Compared with that in non-transfection group, the cell debris increased significantly in 200 fold transfection group at TH 72. At TH 24, 48, and 72, the expression of green fluorescent protein was not seen in cells of non-transfection group, whereas it increased in cells of transfection group over transfection time. (2) The transfection rate of Ad-hEGF gene of cells in each transfection group increased gradually over transfection time. At TH 72, the transfection rates of Ad-hEGF gene of cells in 50-200 fold transfection groups were all above 90%, while the transfection rates of Ad-hEGF gene of cells in non-transfection group, 5, and 20 fold transfection groups were (0.51±0.20)%, (62.44±6.23)%, and (75.00±5.43)% respectively, which were obviously lower than the rate in 50 fold transfection group [(93.12±2.55)%, with P values below 0.01]. The mass concentration of EGF in culture supernatant of cells in each transfection group increased gradually over transfection time. At TH 72, the mass concentration of EGF in culture supernatant of cells in 50 fold transfection group was obviously higher than that in each of the other groups (with P values below 0.01). The proliferation activity of cells in each group at TH 24 and 48 was similar (with P values above 0.05). At TH 72, the proliferation activity of cells in 200 fold transfection group was obviously lower than that in other groups (with P values below 0.05). (3) On culture day 1, the biological activity of EGF secreted by cells in two groups was similar (P>0.05). On culture day 3 and 5, the biological activity of EGF secreted by cells in transfection group were obviously higher than that in non-transfection group (with P values below 0.01). (4) At TH 24, the expression levels of CK14 and CK19 of cells in transfection group were higher than those in non-transfection group. (5) The width of scratch in two groups was nearly the same at PSH 0. At PSH 12-48, the migration distance of cells in transfection group was obviously longer than that in non-transfection group (with P values below 0.01).

CONCLUSIONSThe suitable range of MOI of hECs transfected with Ad-hEGF gene is 50-150, and 50 is the optimum. hECs transfected with Ad-hEGF gene with MOI 50 can effectively express the EGF gene and keep its good abilities of proliferation, differentiation, and migration, as well.

Adenoviridae ; Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; EGF Family of Proteins ; genetics ; metabolism ; Epidermis ; cytology ; Genetic Vectors ; Humans ; Keratins ; metabolism ; Male ; Transfection

Objective: To analyze the current status of epidemiological study of burns in China, and to explore the related strategies. Methods: Retrospective or cross-sectional scientific articles in Chinese or English on epidemiological study of burns in China published from January 2005 to December 2015 were systemically retrieved from 4 databases. The databases include PubMed, Embase, China Biology Medicine disc, and Chinese Journals Full-text Database. From the results retrieved, data with regard to publication year, journal distribution, number of institutions participated in the study, affiliation of the first author and its location, and admission time span and age of patients in all the scientific articles were collected. Furthermore, the definition of age range and the grouping method of age of pediatric patients in English articles on epidemiological study of pediatric burns of China were recorded. Data were processed with descriptive statistical analysis. Results: A total of 256 scientific articles conforming to the study criteria were retrieved, among which 214 (83.59%) articles were in Chinese, and 42 (16.41%) articles were in English; 242 (94.53%) articles were retrospective studies, and 14 (5.47%) articles were cross-sectional studies. During the 11 years, the number of the relevant articles was fluctuant on the whole. The scientific articles were published in 130 journals, with 42 English articles in source journals for SCIENCE CITATION INDEX EXPANDED-JOURNAL LIST, accounting for 16.41%, and 116 Chinese articles in Source Journal for Chinese Scientific and Technical Papers, accounting for 45.31%. Totally 215 (83.98%) articles were single-center studies, and 29 (11.33%) articles were multicenter studies which were conducted by three or more centers. The number of affiliations of the first author of articles was 161 in total. The top 10 institutions regarding the article publishing number published 58 articles, accounting for 22.66%. Scientific articles on epidemiological study of burns were retrieved with location of affiliation of the first author in 31 provinces, autonomous regions, and municipalities directly under the Central Government in Mainland China, and also in Taiwan Province and Hong Kong Special Administrative Region, among which Shanghai ranked first with 24 (9.38%) articles published. The admission time span of patients in the articles ranged from 3 months to 47 years, with 120 (46.87%) articles from 3 months to 5 years, 79 (30.86%) articles from 6 to 10 years, and 57 (22.27%) articles more than 10 years, respectively. Regarding the age of patients in the study, 123 articles were on epidemiological study of pediatric burns, and 16 articles on epidemiological study of elderly burns, accounting for 48.05% and 6.25%, respectively. Further analysis of articles on epidemiological study of pediatric burns in English showed that there was no standard definition of age range or unified grouping method of age for pediatric burn patients. Conclusions The epidemiological study of burns in China has been carried out nationwide, but the number of institutions conducted relevant study is not that much, and multicenter epidemiological studies remain scanty. The quality of the articles needs to be further improved. The epidemiological study of elderly burns is relatively deficient and calls for more attention. The epidemiological study of burns in China lacks regularity or continuity in time scope. There is an urgent need for the guideline on classification method for items of epidemiological study of burns in China so as to standardize the related research.

Objective:To investigate the effects of dexmedetomidine on monocyte pyroptosis in peripheral blood of patients with cardiac valve replacement.Methods:Forty-four American Society of Anesthesiologists physical status Ⅱ or Ⅲ patients of both sexes, aged 45-64 yr, with body mass index of 18-25 kg/m 2, of New York Heart Association Ⅱ or Ⅲ, scheduled for elective cardiac valve replacement, were divided into 2 groups ( n=22 each) using a random number table method: dexmedetomidine group (group Dex) and normal saline group (group NS). In group Dex, dexmedetomidine was intravenously infused in a dose of 0.5 μg/kg over 10 min starting from the end of anesthesia induction, followed by a continuous infusion at 0.5 μg·kg -1·h -1 until the end of operation, while the equal volume of normal saline was given instead of dexmedetomidine in group NS.Before skin incision (T 1), at 30 min after the beginning of cardiopulmonary bypass (CPB) (T 2), immediately after the end of CPB (T 3) and at 24 h after CPB (T 4), the blood samples of internal jugular vein were collected for determination of the concentrations of plasma interleukin-18 (IL-18) and IL-1β (by enzyme-linked immunosorbent assay), and the expression of NOD-like receptor family, pyrin domain containing 3 (NLRP3), caspase-1 and gasdermin-D (GSDMD) in monocytes (by Western blot). The intraoperative consumption of propofol, sufentanil and norepinephrine, time of postoperative mechanical ventilation and time of intensive care unit stay were recorded. Results:The levels of plasma IL-18 and IL-1β and expression of NLRP3, caspase-1 and GSDMD in monocytes were significantly higher at T 2-4 than at T 1 in two groups ( P<0.05). Compared with group NS, the levels of plasma IL-18 and IL-1β were significantly decreased and the expression of NLRP3, caspase-1 and GSDMD was down-regulated at T 2-4, postoperative mechanical ventilation time was shortened ( P<0.05), and no significant change was found in the consumption of propofol, sufentanil and norepinephrine and time of intensive care unit stay in group Dex ( P>0.05). Conclusion:The mechanism by which dexmedetomidine reduces inflammatory responses may be related to inhibiting the NLRP3/caspase-1 pathway and reducing monocyte pyroptosis in the patients undergoing cardiac valve replacement.