Establishment of a diagnostic model for glomerular micro thrombosis in patients with lupus nephritis based on machine learning / 中华风湿病学杂志

Objective:To establish a diagnostic model for glomerular micro thrombosis (GMT) in lupus nephritis through clinical indicators.Methods:A continuous collection of patients diagnosed with lupus nephritis (LN) by renal biopsy in the Department of Nephrology, Shenzhen Second People's Hospital, from January 2010 to March 2021. All patients were admitted and discharged through the inclusion and exclusion criteria. Demographic data, clinical characteristics, biochemical indicators, and immune indicators were collected. A GMT diagnosis model was established from the most important variables among the abovementioned variables through machine learning and Logistic stepwise regression analysis. The model was presented through a nomogram. The receiver operating characteristic curve (ROC), the clinical decision curve and the calibration curve were used to evaluate the model discrimination, clinical use and accuracy, respectively. The internal verification of the model was carried out by repeated sampling 500 times by the Bootstrap method.Results:There were a total of 129 patients with lupus nephritis including the study, including 117 females (90.7%); the average age was (34±11) years. There were 39 patients with GMT (30.2%). Using machine learning to screen out the top 10 important variables from 47 candidate variables, then through logistic stepwise regression analysis, five variables were further screened to establish the diagnostic model of GMT, namely hemoglobin [ OR(95% CI)=0.966(0.943, 0.990), P=0.005], serum C3 [ OR(95% CI)=0.133(0.022, 0.819), P=0.030], systolic blood pressure [ OR(95% CI)=1.027(1.005, 1.049), P=0.017], lymphocyte count [ OR(95% CI)=0.462(0.213, 0.999), P=0.049], and TT [ OR(95% CI)=1.260(0.993, 1.597), P=0.057]. Draw up the equation of the GMT diagnosis model of lupus nephritis and establish a nomogram to present the model. The area under curve (AUC) of the diagnostic model was 0.823, 95% CI(0.753, 0.893), indicating that the model had a reasonable degree of discrimin-ation. The Hosmer-Lemeshow test showed a perfect fit between the predicted GMT risk and the observed GMT risk ( χ2= 14.62, P=0.067). The clinical decision curve and clinical impact curve reflect that the model had a good clinical application value, especially when the threshold probability is between 0.4 and 0.6, the application value is more significant. In addition, after 500 repeated samplings by the Bootstrap method, the average AUC was 0.825, 95% CI(0.753, 0.893), which is basically the same as the AUC obtained by the original model. Conclusion:We established a diagnostic model of GMT inLN based on clinical indicators through machine learning and logistic stepwise regression analysis. It is used for early diagnosis of the risk of GMT before the renal biopsy.

Effects of short-term exposure to ambient airborne pollutants on COPD-related mortality among the elderly residents of Chengdu city in Southwest China

BACKGROUND@#Chronic obstructive pulmonary disease (COPD) has become a severe global burden in terms of both health and the economy. Few studies, however, have thoroughly assessed the influence of air pollution on COPD-related mortality among elderly people in developing areas in the hinterland of southwestern China. This study is the first to examine the association between short-term exposure to ambient airborne pollutants and COPD-related mortality among elderly people in the central Sichuan Basin of southwestern China.@*METHODS@#Data on COPD-related mortality among elderly people aged 60 and older were obtained from the Population Death Information Registration and Management System (PDIRMS). Data on airborne pollutants comprised of particulate matter < 2.5 μm in aerodynamic diameter (PM@*RESULTS@#A total of 61,058 COPD-related deaths of people aged 60 and older were obtained. Controlling the influences of daily temperature and relative humidity, interquartile range (IQR) concentration increases of PM@*CONCLUSIONS@#Increased concentrations of ambient airborne pollutants composed of PM

Establishment of HPLC Fingerprint ，Chemical Pattern Recognition Analysis and Content Determination of the Leaves of Toricellia angulata from Different Regions / 中国药房

OBJECTIVE：To provide reference for the quality control of the leaves of Toricellia angulata . METHODS ：HPLC method was adopted. The determination was performed on Agela Promosil C 18 column with 0.2％ phosphoric acid solution-acetonitrile（gradient elution ）as mobile phase at the flow rate of 1.0 mL/min. The detection wavelength was set at 210 nm，and column temperature was 35 ℃. The sample size was 10 μL. HPLC fingerprint of 10 batches of the leaves of T. angulata was established and similarity evaluation was conducted by using Similarity Evaluation System of TCM Chromatographic Fingerprint（2004 edition）. The chromatographic peak was identified by comparing with the chromatogram of reference substance. Cluster analysis ，PCA and PLS-DA were used to identify chemical patterns ，and the quality differential markers were screened. The contents of hyperoside and isoquercitrin were determined by the same HPLC. RESULTS ：The similarities of HPLC fingerprint of 10 batches of the leaves of T. angulata with control fingerprint were 0.923-0.983. A total of 11 common peaks were identified ，and the peaks 4 and 5 were hyperoside and isoquercitrin ，respectively. Results of cluster analysis ，PCA and PLS-DA showed that 10 batches of leaves of T. angulata could be divided into two categories ，Y10 was clustered into one category ，and others were clustered into one category. PLS-DA analysis showed that 6 common peaks （peaks 4，3，10，2，6 and 11） with variable importance projection （VIP）greater than 1 were selected. Average contents of hyperoside and isoquercitrin in 10 batches of the leaves of T. angulata were 0.47-6.97，0.21-1.87 mg/g，respectively. CONCLUSIONS ：Established HPLC fingerprint and the method for content determination are stable and reliable ，and can be used for the quality control of the leaves of T. angulata from different areas. Six quality differential markers including hyperoside in the leaves of T. angulata from different areas are qnyz202034） preliminarily screened.

Effects of Ophiopogon D combined with cyclooxygenase-2 silencing on proliferation, migration and invasion of human pancreatic cancer BxPC-3 cells / 国际肿瘤学杂志

Objective:To explore the effects of Ophiopogon D combined with cyclooxygenase-2 (COX-2) gene silencing on the proliferation, migration and invasion of human pancreatic cancer BxPC-3 cells.Methods:BxPC-3 cells were divided into blank control group, Ophiopogonin D high-dose group (40 μmol/L), medium-dose group (20 μmol/L) and low-dose group (10 μmol/L). The COX-2-slienced cells were divided into control group, COX-2 inhibited group (50 pmol/ml siRNA-COX-2), Ophiopogonin D group (20 μmol/L) and combination treatment group (Ophiopogonin D 20 μmol/L+ 50 pmol/ml siRNA-COX-2). The proliferation activity of BxPC-3 cells was detected by CCK-8, and the migration distance of BxPC-3 cells was detected by scratched assay. The invasion degree of BxPC-3 cells was detected by Transwell, the relative expression level of COX-2 gene in BxPC-3 cells was detected by real-time quantitative PCR (RT-qPCR), and the relative expressions of COX-2, hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) proteins in BxPC-3 cells were detected by Western blotting.Results:The cell proliferation rates of blank control group, Ophiopogonin D high-dose, medium-dose and low-dose groups were (100.0±4.9)%, (71.8±5.4)%, (80.5±5.8)% and (89.7±5.7)%, respectively. The migration distances were (279.8±24.0) μm, (141.9±21.2) μm, (168.8±37.1) μm and (224.6±19.9) μm, respectively. The absorbance ( A) values of invasion number were 1.107±0.095, 0.390±0.030, 0.596±0.017 and 0.826±0.034, respectively.There were statistically significant differences ( F=19.770, P<0.001; F=48.270, P<0.001; F=198.400, P<0.001). The above indexes of the Ophiopogonin D high-, medium- and low-dose groups were significantly lower than those in the blank control group (all P<0.05). The relative expression levels of COX-2 gene were 1.007±0.178, 0.387±0.169, 0.567±0.142 and 0.740±0.030, respectively, and the relative protein expression levels were 1.000±0.033, 0.654±0.085, 0.762±0.110 and 0.881±0.049, respectively, with statistically significant differences ( F=10.280, P=0.004; F=11.780, P=0.003). The above indexes of the Ophiopogonin D high- and medium-dose groups were significantly lower than those in the blank control group (all P<0.05), and there was no statistically significant difference between the Ophiopogonin D low-dose group and blank control group (both P>0.05). The medium-dose of Ophiopogonin D (20 μmol/L) was selected as the subsequent concentration.After COX-2 silencing, the proliferation rates of the control group, COX-2 inhibited group, Ophiopogonin D group and combination treatment group were (100.0±2.8)%, (68.4±6.7)%, (67.7±5.9)% and (57.0±8.5)%, respectively, the migration distances were (274.4±23.8) μm, (217.0±18.8) μm, (186.2±18.6) μm and (115.7±15.8) μm, respectively, and the A values of invasion number were 1.143±0.092, 0.791±0.058, 0.715±0.026 and 0.424±0.058, respectively, with statistically significant differences ( F=34.430, P<0.001; F=103.400, P<0.001; F=131.100, P<0.001). The proliferation rates, migration distances and invasion numbers in each treatment group were significantly lower than those in the control group (all P<0.001). Compared with the COX-2 inhibited group and Ophiopogonin D group, the cell proliferation, migration and invasion were significantly inhibited in the combination treatment group (all P<0.05). Compared with the Ophiopogonin D group, only the migration distance of the COX-2 inhibited group was significantly different ( P<0.05). The relative expression levels of COX-2 protein in the above groups were 0.995±0.037, 0.779±0.060, 0.806±0.076 and 0.645±0.079, respectively, the relative expression levels of HIF-1α were 1.083±0.104, 0.749±0.070, 0.736±0.070 and 0.394±0.016, respectively, and the relative expression levels of VEGF protein were 1.016±0.103, 0.757±0.090, 0.745±0.021 and 0.603±0.023, respectively, with statistically significant differences ( F=14.650, P=0.001; F=45.220, P<0.001; F=18.180, P<0.001). The expression levels of the three proteins in each treatment group were significantly lower than those in the control group (all P<0.05). Compared with the COX-2 inhibited group and Ophiopogonin D group, the relative protein expression levels of COX-2, HIF-1α and VEGF in the combination treatment group were significantly decreased (all P<0.05). Compared with the Ophiopogonin D group, there were no significant differences in the expression of the three proteins in the COX-2 inhibited group (all P>0.05). Conclusion:Ophiopogon D combined with COX-2 gene silencing can inhibit the proliferation, migration and invasion of pancreatic cancer cells, and the mechanism may be related to the inhibition of COX-2 pathway and the decrease of HIF-1α and VEGF protein expression levels.

Correlation between hemoglobin and progression of renal function in patients with proliferative lupus nephritis / 中华肾脏病杂志

Objective:To explore the correlation between hemoglobin (Hb) and progression of renal function in patients with proliferative lupus nephritis (PLN).Methods:Data of biopsy-proven PLN patients from January 2010 to February 2019 in Department of Nephrology, the First Affiliated Hospital of Shenzhen University were retrospectively analyzed. The patients were divided into stable renal function group and renal function progression group according to changes of renal function including serum creatinine doubling/end-stage renal disease (ESRD) and the demographic, clinical, and pathological characteristics were compared between the two groups. Cox regression and smooth curve fitting of generalized additive model analysis were used to explore the correlation between Hb and progression of renal function.Results:A total of 87 patients were included in this study. The age was (34.97±11.95) years old and 79 cases (90.80%) were females. During follow-up of 19.0(6.5, 43.5) months, renal function of 15 patients (17.24%) progressed. Compared with stable renal function group, Hb level of patients in renal function progression group were lower ( t=3.887, P<0.001), and serum creatinine ( Z=-2.466, P=0.003) and uric acid ( t=-2.154, P=0.034) were higher. As to the pathological characteristics, the proportion of class lupus nephritis-IV, renal tubular atrophy and interstitial fibrosis in renal function progression group were higher than those in stable renal function group, but there was no statistical difference between the two groups (all P>0.05). Multivariate Cox regression analysis indicated that high Hb was an independent protective factor of renal function progression in PLN patients ( HR=0.893, 95% CI 0.836-0.954, P=0.001). The risk of progression to serum creatinine doubling/ESRD would decrease by 10.7% when Hb increased by 1 unit (g/L). Smooth curve fitting of generalized additive model analysis showed that Hb was linearly correlated with the risk of renal function progression ( P=0.100). Receiver operating characteristic curve indicated that the risk of doubling serum creatinine/ESRD in PLN patients would be relatively low when Hb level was above 77 g/L (area under the curve 0.788, best threshold 77 g/L, sensitivity 0.600, specificity 0.903). Conclusions:Hb is closely related to progression of renal function in patients with PLN. More attention and management of Hb levels in patients with PLN can play an important role in improving renal prognosis.

Correlation between serum C3 and glomerular microthrombosis in patients with lupus nephritis / 中华肾脏病杂志

Objective:To investigate the correlation between serum C3 and glomerular microthrombosis in patients with lupus nephritis (LN).Methods:Patients who were diagnosed as LN by renal biopsy hospitalized in Department of Nephrology, the First Affiliated Hospital of Shenzhen University from January 2010 to February 2019 were retrospectively analyzed and they were divided into glomerular microthrombosis group (GMT group) and non-glomerular microthrombosis group (non-GMT group). The demographic data, clinical characteristics, pathology and prognosis of the two groups were compared. Logistic regression and smooth curve fitting of generalized additive mixed model analysis were used to explore the correlation between serum C3 and glomerular microthrombosis. Renal prognosis of the two groups were compared by the Kaplan-Meier survival curve.Results:A total of 116 patients were enrolled, aged (32.79±11.43) years old, in which 108 cases (93.10%) were female. Thirty-seven patients (31.90%) were confirmed to be combined with GMT (GMT group) and 79 cases were not (non-GMT group). Compared with the non-GMT group, patients in the GMT group were relatively older ( t=-2.876, P=0.002), with higher proportion of hypertension ( χ2=7.492, P=0.006), higher urine protein quantitation ( Z=-2.115, P=0.003), lower levels of eGFR and serum complement C3 ( Z=3.469, P<0.001; t=1.744, P<0.001), higher systemic lupus erythematosus disease activity index ( t=-2.758, P=0.007). As to the pathological characteristics, type IV LN patients were the majority (72.97%). Proportion of crescents and pathological activity indicators of the GMT group were higher ( Z=-1.866, P=0.002; t=-5.005, P<0.001), nuclear fragmentation, endothelial hyperplasia and renal tubular atrophy were more serious ( χ2=14.987, P<0.001; χ2=15.695, P<0.001; χ2=4.130, P=0.042). Multivariate logistic regression analysis indicated that serum complement C3 was a relational factor of the formation of GMT in LN patients ( OR=0.966, 95% CI 0.938-0.995, P=0.023). Smooth curve fitting of generalized additive mixed model analysis indicated that level of complement C3 had a linear relationship with the changing trend of GMT. The Kaplan-Meier curve showed that there were statistical differences between the two groups in terms of complete remission of urine protein (Log-rank χ2=5.858, P=0.016) and doubled serum creatinine/end-stage renal disease (Log-rank χ2=3.945, P=0.047). Conclusions:Serum C3 is closely related to the formation of GMT in LN patients, and statistical differences were demonstrated in the renal prognosis of GMT group and non-GMT group.

Association between gaseous pollutants and emergency ambulance dispatches for asthma in Chengdu, China: a time-stratified case-crossover study

OBJECTIVES@#The association between concentrations of sulfur dioxide (SO), nitrogen dioxide (NO), carbon monoxide (CO), ozone (O), and emergency ambulance dispatches (EADs) for asthma was explored in the central Sichuan Basin of southwestern China for the first time.@*METHODS@#EADs for asthma were collected from the Chengdu First-Aid Command Center. Pollutant concentrations were collected from 24 municipal environmental monitoring centers and including SO, NO, CO, daily 8-h mean concentrations of O (O-8 h), and particulate matter less than 2.5 μm in aerodynamic diameter (PM). The climatic data were collected from the Chengdu Municipal Meteorological Bureau. All data were collected from years spanning 2013-2017. A time-stratified case-crossover design was used to analyze the data.@*RESULTS@#After controlling for temperature, relative humidity, and atmospheric pressure, IQR increases in SO (13 μg/m), NO (17 μg/m), and CO (498 μg/m) were associated with 18.8%, 11.5%, and 3.1% increases in EADs for asthma, respectively. The associations were strongest for EADs and SO, NO, and CO levels with 3-, 5-, and 1-day lags, respectively.@*CONCLUSIONS@#This study provides additional data to the limited body of literature for potential health risks arising from ambient gaseous pollutants. The results of the study suggest that increased concentrations of SO, NO, and CO were positively associated with emergency ambulance dispatches for asthma in Chengdu, China. Further studies are needed to investigate the effects of individual air pollutants on asthma.

Sivelestat alleviates nonalcoholic steatohepatitis in mice through inhibiting activation of Kupffer cells / 中华肝脏病杂志

Objective@#To investigate the role of neutrophil elastase inhibitor, sivelestat, in preventing and treating nonalcoholic steatohepatitis (NASH) and its underling mechanisms.@*Methods@#A total of forty 4-week-old male C57BL/6J ApoE-/-mice were equally divided into the following four groups: standard chow (SC)+isotonic saline; SC+sivelestat; high-fat, high-cholesterol (HFHC) diet+isotonic saline; and HFHC+sivelestat. These mice were treated with above methods for 12 weeks. Blood and liver tissue samples were collected to measure biochemical parameters, hepatic steatosis and non-alcoholic fatty liver disease (NAFLD) activity score (inflammation) were evaluated by oil red O staining and HE staining, respectively. The mRNA and protein expression levels of hepatic inflammatory cytokines, CD68, and F4/80 were determined by quantitative RT-PCR and immunohistochemistry, respectively. Comparison of means between the four groups was made by one-way analysis of variance, and comparison between any two groups was made by the LSD or SNK method (for data with homogeneity of variance) or the Tamhane or Dunnett method (for data with heterogeneity of variance).@*Results@#Mice fed with an HFHC diet for 12 weeks developed typical pathological features of NASH compared with those fed with SC. Compared with mice fed with HFHC diet without sivelestat, those treated with HFHC and sivelestat exhibited the following features: (1) significantly reduced fast blood glucose, blood cholesterol, and hepatic biochemical parameters, as well as increased insulin sensitivity; (2) significantly reduced NAFLD activity score (5.71±1.11 vs 3.16±1.16, P < 0.05); (3) reduced monocyte chemoattractant protein-1 and tumor necrosis factor -α; (4) significantly reduced mRNA levels of CD68 and F4/80; and (5) reduced expression of CD68 in the liver.@*Conclusion@#Sivelestat alleviates the hepatic steatosis and inflammation of NASH in mice by inhibiting the activation of Kupffer cells.

Monitoring on main hygiene indicators before and after clean operating rooms are used / 中国感染控制杂志

Objective To compare the main hygiene indicators before and after clean operating rooms are used,evaluate the influencing factors,and find out the improvement measures.Methods In 2015,some cleaning operating rooms in Chengdu were detected,according to different service years and maintenance status,operating rooms were divided into newly-built group,replacement group,and non-replacement group,change in qualified rate of three groups of clean operating room indicators were analyzed.Results A total of 111 cleaning operating rooms were detected,including 56 newly-built operating rooms,and 55 operating rooms (24 in replacement group,31 in non-replacement group) which have been used for more than 1 years.The qualified rate of air cleanliness in newlybuilt group,replacement group,and non-replacement group were 98.21％,100.00％,and 74.19％ respectively,difference among three groups was significantly(P＜0.001),the qualified rate of air cleanliness in newly-built group and replacement group were both higher than non-replacement group,while newly-built group and replacement group was not significantly different (P =1.000);difference in bacterial concentration,static pressure difference,and ventilation frequency of air in operating rooms of three groups were all not statistically significant(all P＞0.05).Conclusion After clean operating room have been used for one year,air cleanliness declined,there was no significant change in static pressure difference and air exchange frequency,which indicates that when concentration of airborne bacteria is qualified,risk of infection due to unqualified air cleanliness still needs to be paid attention,the replacement of high efficiency particulate air filter in clean operating rooms can significantly improve the cleanliness of operating rooms.

MRS in quantitative assessment of lumbar discs degeneration / 中国医学影像技术

Objective To evaluate the value of MRS in quantitative assessment of degeneration of lumbar discs.Methods Totally 82 patients with lumbago underwent lumbar MR scanning.All the discs were classified with Pfirrmann grades in the sequences of sagittal T2WI.The area under N-acetyl peak,under water peak and the ratio of N-acetyl/Water were measured by MRS.Correlation between MRS values and Pfirrmann grade,age were analyzed.Results In 82 patients,204 lumbar discs were measured by MRS.There were 89,73,39,3 discs in Pfirrmann Ⅱ,Ⅲ,Ⅳ,V respectively.The areas of N-acetyl,water peak and N-acetyl/Water ratio of nucleus region were positively correlated with Pfirrmann grading,respectively (rs =-0.460,-0.204,-0.526,all P＜0.05).There were 62,25,37,51,29 discs in patients aged ＜30,30-39,40-49,50-59,＞59 years respectively.The ares of N-acetyl peak,N-acetyl/Water ratio of nucleus region was negatively correlated with the age (rs=-0.247,-0.385,both P＜0.05).Conclusion MRS can be used for quantitative assessment of lumbar discs degeneration.

Study on anti-inflammatory effect and underlying mechanism of DMY in LPS-induced septic mice / 中国免疫学杂志

Objective:To investigate the effect of dihydromyricetin (DMY) on LPS-induced septic shock in mice and the related underlying mechanism.Methods:The LPS-induced septic shock mice model was established after the mice were pre-treated by DMY for 7 days.The mortality rate was calculated at 24,48,72,96,120,144 and 168 h after the mice were intraperitoneal injected with LPS.For elucidation of underlying mechanism ,RAW246.7 were pre-incubated with DMY for 1 h,and then stimulated by LPS 100 ng/ml.Western blot was performed for determination of P-ERK,P-JNK and P-p38 expression.Immunohistochemistry was applied to explore c-Fos and c-Jun nucleus translocation.Results:DMY could significantly inhibit LPS-induced mice mortality.Inhibitory effect of DMY on the phosphorylation of JNK and p 38 contributed to the anti-inflammatory effect of DMY in vivo.Furthermore , DMY obviously prevented c-Fos and c-Jun nucleus translocation.Conclusion:The anti-inflammatory effect of DMY is attributed to the suppression on c-Fos and c-Jun nucleus translocation ,via inhibition of the phosphorylation of JNK and p 38.

Changes in apparent diffusion coefficient and T2 values in the lumbar intervertebral disc under short-time axial load / 中国组织工程研究

BACKGROUND:Disc functional magnetic resonance imaging studies are mostly carried out under lying and a non-load state, and do not reflect the changes in morphology and function of the upright human body under disc load conditions. Therefore, we need to study characteristics of disc functional magnetic resonance imaging in the upright state. OBJECTIVE: To analyze the effect of axial load on apparent diffusion coefficient and T2 of intervertebral discs. METHODS:The study consisted of 17 patients with low back pain aged 34-65 years. Before and after axial load, T2 weighted MR imaging, T1 weighted MR imaging, diffusion tensor imaging, and T2-mapping imaging of the lumbar spine were performed. Load quality was 40%-50% body weight. At 10 minutes after axial load, another diffusion tensor imaging was performed. After 15-minute load, another T2-mapping sequence was scanned. Diffusion tensor imaging scan parameters: single echo-planar imaging, repetition time 2 500 ms, echo time 89 ms, six diffusion directions, b value of 400 s/mm2, sweep time 4:10 minutes. Raw data of diffusion tensor imaging were used to construct apparent diffusion coefficient map and b0 map. Apparent diffusion coefficient value of intervertebral discs was calculated before and after loading. T2 map was automaticaly constructed using T2-mapping sequence to measure apparent diffusion coefficient and T2 values in the whole intervertebral disc of nucleus pulposus, and the changes of them were analyzed under short-time axial load. RESULTS AND CONCLUSION:Pfirrmann grading results in 17 patients with 85 discs were obtained as folows: 0 in Grade I, 26 in Grade II, 19 in Grade III, 30 in Grade IV, and 10 in Grade V. Al 85 disc T2 relaxation time mapping and 84 disc apparent diffusion coefficient mapping were accepted. Under short-time axial load in 84 discs, apparent diffusion coefficient reduced in the whole disc (reduced 38×10-3 mm2/s,Z=2.567,P 0.05). These results suggest that changes in apparent diffusion coefficient and T2 values were different due to different Pfirrmann grades under short-time axial load. To evaluate magnetic resonance imaging function of intervertebral discs, we should choose different evaluation method according to different degeneration degrees.

Design and fabrication of the custom-made titanium condyle by selective laser melting technology / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To design and fabricate the custom-made titanium mandibular condyle by the reverse engineering technology combined with selective laser melting (SLM) technology and to explore the mechanical properties of the SLM-processed samples and the application of the custom-made condyle in the temporomandibular joint (TMJ) reconstruction.</p><p><b>METHODS</b>The three-dimensional model of the mandibular condyle was obtained from a series of CT databases. The custom-made condyle model was designed by the reverse engineering software. The mandibular condyle was made of titanium powder with a particle size of 20-65 µm as the basic material and the processing was carried out in an argon atmosphere by the SLM machine. The yield strength, ultimate strength, bending strength, hardness, surface morphology and roughness were tested and analyzed. The finite element analysis (FEA) was used to analyze the stress distribution.</p><p><b>RESULTS</b>The complex geometry and the surface of the custom-made condyle can be reproduced precisely by the SLM. The mechanical results showed that the yield strength, ultimate strength, bending strength and hardness were (559±14) MPa, (659±32) MPa, (1 067±42) MPa, and (212±4)HV, respectively. The surface roughness was reduced by sandblast treatment.</p><p><b>CONCLUSIONS</b>The custom-made titanium condyle can be fabricated by SLM technology which is time-saving and highly digitized. The mechanical properties of the SLM sample can meet the requirements of surgical implant material in the clinic. The possibility of fabricating custom-made titanium mandibular condyle combined with the FEA opens new interesting perspectives for TMJ reconstruction.</p>

Development and evaluation of a high-fat/high-fructose diet-induced nonalcoholic steatohepatitis mouse model / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To develop and evaluate a mouse model of nonalcoholic steatohepatitis (NASH) induced by a high-fat and high-fructose (HFHFr) diet.</p><p><b>METHODS</b>Six-week-old C3H mice were randomly divided into groups for HFHFr diet experimental modeling, high fat-only (HF) diet controls, high fructose-only (HFr) diet controls, and standard chow (SC) diet controls. The standard HFHFr diet was modified so that it consisted of 76.5% standard chow, 12% lard, 1% cholesterol, 5% egg yolk powder, 5% whole milk powder, and 0.5% sodium cholate, along with 20% fructose drinking water. At the end of experimental weeks 4, 8, and 16, measurements were taken for the NASH-related parameters of body mass, serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), lipid profile, and wet liver weight (upon sacrifice). In addition, histological changes in the liver were evaluated by hematoxylin-eosin (HE) and oil red O staining. The significance of differences between groups was assessed by statistical analysis, using the</p><p><b>METHODS</b>of t-test, Wilcoxon rank sum test, x2 test, F test or Fisher's test as appropriate.</p><p><b>RESULTS</b>As compared to the mice in the SC group at the corresponding time points, the mice in the HFHFr and HF groups showed significantly higher body mass and wet liver weight, as well as more extensive and robust lipid disposition in hepatic tissues as evidenced by oil red O staining. However, HE staining indicated that the HFHFr and HF groups had different degrees of macrosteatosis accompanied with intralobular inflammatory foci, with the former showing more remarkable NASH-related histological changes. Analysis at the end of week 16 showed that about 80% of the mice in the HFHFr group had developed NASH [nonalcoholic fatty liver disease (NAFLD) activity score (NAS): less than 5]. The levels of low-and high-density lipoprotein (LDL and HDL) cholesterol, as well as the levels of ALT and AST, were increased from the end of week 4 to the end of week 8 for the HFHFr and HF groups. At the end of week 16, the two groups differed in the extent of increase in total cholesterol and LDL and HDL cholesterol, with only the HFHFr group showing statistically significant changes. Specifically, at the end of week 16, the HFHFr group showed ALT levels of 108.5 +/- 93.34 U/L (F=5.099, P =0.005 vs. HF group: 44.30 +/- 35.71 U/L, HFr group: 46.70 +/- 17.95 U/L, SC group: 24.70 +/- 6.57 U/L), AST levels of 316.30 +/- 208.98 U/L (F=6.654, P=0.001 vs. HF: 132.12 +/- 75.43 U/L, HFr: 143.30 +/- 38.53 U/L, SC: 122.60 +/- 12.76 U/L), total cholesterol levels of 5.18 +/- 0.58 mmol/L (F=72: 470, P =0.000 vs. HF: 3.94 +/- 0.75 mmol/L, HFr: 2.30 +/- 0.50 mmol/L, SC: 2.02 +/- 0.24 mmol/L), HDL cholesterol levels of 3.05 +/- 0.49 mmol/L (F=25.413, P =0.000 vs. HF: 2.65 +/- 0.54 mmol/L HFr: 1.77 +/- 0.47 mmol/L, SC: 1.58 +/- 0.16 mmol/L), LDL cholesterol levels of 1.11 +/- 0.23 mmol/L (F =83.297, P =0.000 vs. HF: 0.72 +/- 0.17 mmol/L, HFr: 0.27 +/- 0.04 mmol/L, SC: 0.20 +/- 0.05 mmol/ L).</p><p><b>CONCLUSION</b>The present study suggests that a mouse model of NASH can be successfully induced by a 16-week modified HFHFr diet.</p>

The analysis of variation of Han male children and adolescent bone age of wrist-hand in Beijing and Guangzhou / 中华放射学杂志

Objective To study the difference of Han male children and adolescent bone age of wrist-hand in Beijing and Guangzhou.Methods Bone age (BA) of left hand-wrist was assessed using X-ray by two radiologists based on CHN atlas method in 993 healthy children and adolescents (age range:1.0-19.0 years).The radiologists were blinded to the chronological age (CA) of those children.The interobserver variations were analyzed for evaluating the reliability of CHN Atlas method.The difference between CA and BA were separately assessed,and were analyzed by t test.Results Close correlation was found between BA and CA (r =0.969,0.957,P ＜ 0.01) in both two regions.The bone age was advanced at 1.0-3.9,and 7.0-15.9 years in Beijing boys,and at 1.0-2.9,6.0-7.9 years in Guangzhou bpys.There was significant difference at 1.0-1.9,9.0-14.9 years between Beijing and Guangzhou.Conclusions The bone age of Han male children adolescent in Beijing and Guangzhou area has the characteristic of acceleration.There is significance difference at some years between Beijing and Guangzhou,and the results can provide potential value for the further study of BA and clinical medicine.

3D MRI findings of anterior cruciate ligament reconstruction at follow-up / 中华放射学杂志

ObjectiveTo investigate the postoperative 3D MRI appearances and their evolvement patterns of ACL grafts and bone tunnels at follow-up.Methods There were 26 double bundles ACL reconstructions and 16 single bundle ACL reconstructions,and a total of 56 follow-up 3D MR Imaging.MR images were reconstructed with MPR technique to evaluate grafts,bone tunnels,fixers and associated.complications.Proportions of grafts with hypointensity or hyperintensity and occurrence rates of marrow edema around bone tunnels were calculated respectively among groups of different periods after operation.ResultsThere were 24 grafts of hypointensity and 32 grafts of hyperintensity.Grafts of 2 cases were suspended with cross pins within femoral tunnels,graft of 1 case was suspended with an endobutton within the femoral tunnel,and grafts of other sites were fixed with interference screws.In the three periods as 3 months,6 to 9 months and over 12 months after cruciate ligament reconstruction,proportions of hypointensive grafts were 20/25,0/14 and 4/10 respectively,while proportions of hyperintensive grafts were 5/25,14/14 and 6/10 respectively,occurrence proportions of marrow edema around bone tunnels were 54/54,10/32 and 4/26 respectively.There was 1 tear graft,4 tibial tunnels placed anteriorly with ACL graft impingement on the intercondylar roof,3 femoral tunnels placed anteriorly,and 2 bone tunnels with mismatching interference screws.Conclusion3D MRI can accurately demonstrate the state of ACL grafts,bone tunnels,fixers and associated complications.Intensity of grafts presented a rise and reduce pattern after operation.

The effect of axial loading to the lumbar intervertebral discs MR diffusion characteristics / 中华放射学杂志

Objective To analysis the effect of axial loading to ADC value, FA of lumbar intervetebral discs. Methods Forty five patients with low back pain (age range, 25 to 54 years) were evaluated with MR T2WI, MR T1WI and diffusion tensor imaging (DTI) of the lumbar spine. Following axial loading with 40% to 50% body weight for 10 minutes, a repeat DTI was performed. DTI were obtained by using an echo-planar imaging ( EPI ) sequence, TE 89 ms, TR 2500 ms, b value of 400 s/mm2,6 noncollinear diffusion directions. Scan time was approximately 4 min 10 s. An isotropic ADC map, FA map and bo map were calculated from DTI sequence. The mean ADC value, FA prior to and following axialloading were analyzed with t test and Rank Sum test. Results Forty five patients with 225 discs were evaluated and 223 discs were included in the study except for 2 calcified discs. The Pfirrmann grading results were as following: 100 Grade Ⅱ , 48 Grade Ⅲ, 59 Grade Ⅳ, and 16 Grade Ⅴ. No significant difference existed in the mean ADC value before [ ( 1666 ± 252 ) × 10-3 mm2/s ] and after [ ( 1662 ± 253 ) ×10 -3 mm2/s ] axial loading ( Z = - 1.363, P ＞ 0.05 ), but the mean FA [ ( 301 ± 104 ) × 10 -3, ( 316 ±112) × 10-3 ] value increased ( Z = - 2.794, P ＜ 0.05 ). The paired-samples t test show that the mean ADC value [ ( 1685 ± 190) × 10-3 mm2/s, ( 1624 ± 180) × 10-3mm2/s] of Grade Ⅲ discs decreased after axial loading, t=3.513, P＜0. 05, Grade Ⅲ, Ⅳdiscs mean FA value [(300±87) ×10-3, (326±87) ×10-3 for Grade Ⅲ and (348 ±67) × 10-3, (351 ± 71 ) × 10-3 for Grade Ⅳ ] increased, t = - 2. 210,- 2.006, P ＜ 0.05. No significant difference existed in Grade Ⅱ , Ⅳ and Ⅴ discs ADC value, all the P ＞0.05. No significant difference existed in Grade Ⅱ and Ⅴ discs FA value, both the P ＞ 0.05. Conclusions Short time axial loading mainly affect the mildly degenerated discs, the ADC value decreases and the disc diffusion ability decreases. No obvious change in ADC value or disc diffusion ability existed in the normal and severely degenerated discs.

Clinical observation on contraception effects of three types of intrauterine device / 中国综合临床

Objective To observe the clinical contraeeption effects of GyneFix IN IUD,MCu IUD and TCu220C IUD.Methods From January 2005 to December 2006,comparative study was carried out by randomly applying 3 different types of IUDs(GyneFix IN,MCu and TCu220C IUD) for 300 healthy women.Follow-up survey was taken after 1,3,6,and 12 months.Results The pregnancy rates with IUD among 3 types of IUDs showed no significant difference(P>0.05).The expulsion rates of GyneFix IN IUD and MCu IUD were lower than that of TCu220C IUD(P<0.01).The removal rate of GyneFix IN IUD and MCu IUD were lower than that of TCu220C IUD(P<0.05).The 12 months cumulative continuation rates of GyneFix IN IUD and MCu IUD were higher than that of TCu220C IUD(P<0.01).Conclusions GyneFix IN IUD and MCu IUD can be recommended for clinical use based upon the advantages of lower pregnancy rate,lower removsl rate because of side-effect and higher cumulative continuation rate.Proper IUD should be selected depending on individuals,in order to increase the contraception effects and decrease the side-effects.

Isotropic three-dimensional turbo spin echo MRI of the popliteomeniscal fasciculi / 中华放射学杂志

Objective To investigate the effect of slice orientation on the popliteomeniscal fasciculi (PMF) MR imaging and its normal MRI appearances. Methods Volumetric MRI data of 40 knees of healthy volunteers were acquired using an isotropic 3D turbo spin echo (TSE) MR sequence. The posterior tangential line to both femoral condyles was used as the reference line, and the long axis sectional images of the popliteal hiatus region were reformatted at 0°, 15°, 30°, 45°, 60°, 75° and 90° to the reference line. The MRI appearances of the PMF were scored respectively and classified. The final scores of the PMF at each slice angle were statistically analyzed by a repeated measure ANOVA. Results At 0°, 15°, 30°, 45°, 60°, 75° and 90° slice angles: scores of the anteroinferior fasciculi were (1.7±0.7), (1.8±0.6), (1.9±0.6), (2.0±0.7), (1.9±0.7), (1.8±0.8) and (1.0±0.5),respectively. Scores of the posterosuperior fasciculi were (1.5±0.7), (1.9±0.7), (2.1±0.6), (2.2±0.6),(2.2±0.6), (2.0±0.8) and (1.7±0.8), respectively. There were statistically significant differences in the average scores at each slice angle for both anteroinferior fasciculi (F = 29.744, P = 0.000) and posterosuperior fasciculi (F = 19.770,P =0.000). The anteroinferior fasciculi and the posterosuperior fasciculi had highest average scores at the angle of 45°. The percentage of type A, B and C of anteroinferior fascicali were 20.0% (8/40), 75.0% (30/40) and 5.0% (2/40), respectively. The percentage of type A, B and C of posterosuperior fasciculi were 37.5% (15/40) ,62.5% (25/40) and 0% (0/40) ,respectively. Conclusion The anteroinferior fasciculi and the posterosuperior fasciculi can be well depicted at the angle of 45° slice orientation.

A medical image semantic modeling based on hierarchical Bayesian networks / 生物医学工程学杂志

A semantic modeling approach for medical image semantic retrieval based on hierarchical Bayesian networks was proposed, in allusion to characters of medical images. It used GMM (Gaussian mixture models) to map low-level image features into object semantics with probabilities, then it captured high-level semantics through fusing these object semantics using a Bayesian network, so that it built a multi-layer medical image semantic model, aiming to enable automatic image annotation and semantic retrieval by using various keywords at different semantic levels. As for the validity of this method, we have built a multi-level semantic model from a small set of astrocytoma MRI (magnetic resonance imaging) samples, in order to extract semantics of astrocytoma in malignant degree. Experiment results show that this is a superior approach.