慢Mohs显微描记手术对隆突性皮肤纤维肉瘤的治疗效果及术后二期愈合特点分析

目的总结慢Mohs显微描记手术(sMMS)应用于隆突性皮肤纤维肉瘤治疗的效果,分析术后二期愈合特点。方法回顾性分析2016年—2020年北京大学第一医院的106例隆突性皮肤纤维肉瘤患者的病历资料,统计分析其临床特征、sMMS治疗和二期愈合等相关参数。绘制散点图,采用直线回归方程分析临床资料的关系。结果患者发病年龄集中于20~40岁,男∶女为1∶1.16,95例(89.6%)患者病程>1年,76例(71.7%)患者发病部位为躯干部。sMMS治疗隆突性皮肤纤维肉瘤局部复发率为1.1%(1/106);手术过程中57例(53.8%)患者可以1次手术切净,位于躯干部者更可能需要多次切除(57.9%);根据sMMS 1次手术未切净的主要方位评判,深部未切净为主的患者[含单纯深部未净、边缘及深部未净(深部为主)]占1次手术肿瘤未净总患者数的85.7%。术后常遗留大面积组织缺损,55例(51.9%)创面长径≥10 cm;术后创面随着病程延长逐渐扩大,病程每增加1年,术后皮肤创面长径增加约0.22 cm。接受二期愈合的患者中,50.0%可于3个月内实现伤口愈合,其余患者于3~6个月愈合,两者的皮肤创面长径比较,差异无统计学意义(P>0.05);二期愈合时间与皮肤创面长径无相关性(R^(2)=0.005,P=0.660),躯干部位二期愈合时间与皮肤创面长径无相关性(R^(2)=0.0134,P=0.502),表皮爬行速度与年龄无相关性(R^(2)=0.0008,P=0.859)。结论本研究描述了隆突性皮肤纤维肉瘤患者的临床特征,展示了sMMS治疗的特点及优越性,且初步明确了sMMS之后行二期愈合的可行性。

Meta-analysis of ADH1B and ALDH2 polymorphisms and esophageal cancer risk in China

AIM: To evaluate whether alcohol dehydrogenase-1B (ADH1B) His47Arg and aldehyde dehydrogenase-2 (ALDH2) Glu487Lys polymorphism is involved in the esophageal squamous cell carcinoma (ESCC) risk in Chinese Han population. METHODS: Seven studies of ADH1B and ALDH2 genotypes in Chinese Han population in 1450 cases and 2459 controls were included for meta-analysis. Stratified analyses were carried out to determine the genealcohol and gene-gene interaction with ESCC risk. Potential sources of heterogeneity between studies were explored, and publication bias was also evaluated. RESULTS: Individuals with ADH1B arginine (Arg)/Arg genotype showed 3.95-fold increased ESCC risk in the recessive genetic model [Arg/Arg vs Arg/histidine (His) + His/His: odds ratio (OR) = 3.95, 95% confidence in- terval (CI): 2.76-5.67]. Signif icant association was found in the dominant model for ALDH2 lysine (Lys) allele [glutamate (Glu)/Lys + Lys/Lys vs Glu/Glu: OR = 2.00,95% CI: 1.54-2.61]. Compared with the non-alcoholics, Arg/Arg (OR = 25.20, 95% CI: 10.87-53.44) and Glu/ Lys + Lys/Lys (OR = 21.47, 95% CI: 6.44-71.59) were found to interact with alcohol drinking to increase the ESCC risk. ADH1B Arg+ and ALDH2 Lys+ had a higher risk for ESCC (OR = 7.09, 95% CI: 2.16-23.33). CONCLUSION: The genetic variations of ADH1B His47Arg and ALDH2 Glu487Lys are susceptible loci for ESCC in Chinese Han population and interact substantially with alcohol consumption. The individuals carrying both risky genotypes have a higher baseline risk of ESCC.

Impacts of exposure to 900 MHz mobile phone radiation on liver function in rats

Objective: To study the impacts of exposure to electromagnetic radiation(EMR) on liver function in rats. Methods: Twenty adult male Sprague-Dawley rats were randomly divided into normal group and radiated group. The rats in normal group were not radiated, those in radiated group were exposed to EMR 4 h/d for 18 consecutive days. Rats were sacrificed immediately after the end of the experiment. The serum levels of alanine aminotransferase(ALT) and aspartate aminotransferase(AST), and those of malondialdehyde(MDA) and glutathione(GSH) in liver tissue were evaluated by colorimetric method. The liver histopathological changes were observed by hematoxylin and eosin staining and the protein expression of bax and bcl-2 in liver tissue were detected by immunohistochemical method. Terminal-deoxynucleotidyl transferase mediated nick and labelling(TUNEL) method was used for analysis of apoptosis in liver. Results: Compared with the normal rats, the serum levels of ALT and AST in the radiated group had no obvious changes(P>0.05), while the contents of MDA increased(P<0.01) and those of GSH decreased(P<0.01) in liver tissues. The histopathology examination showed diffuse hepatocyte swelling and vacuolation, small pieces and focal necrosis. The immunohistochemical results displayed that the expression of the bax protein was higher and that of bcl-2 protein was lower in radiated group. The hepatocyte apoptosis rates in radiated group was higher than that in normal group(all P<0.01). Conclusion: The exposure to 900 MHz mobile phone 4 h/d for 18 days could induce the liver histological changes, which may be partly due to the apoptosis and oxidative stress induced in liver tissue by electromagnetic radiation.

Effect of 1,25-dihydroxyvitamin D3 on mast cells tryptase in asthmatic guinea pigs

Objective:To explore the effect of 1,25-dihydroxyvitamin D3 on the mast cell tryptase(MCT) in asthmatic guinea pigs.Methods:A total of 60 male or female healthy guinea pigs were randomly divided into control group(group A),asthmatic group(group B).and 1,25-dihydroxyvitamin D3 group(group C),with 20 cases in each group.To establish asthmatic guinea pig models,1ml peanut oil was tilled into stomach in the morning in group A and group B.and 1 ml peanut oil with 1,25-dihydroxyvitamin D3 was filled into stomach in group C.Airway resistance(Re) of asthmatic guinea pigs was detected,and the bronchoalveolar lavage fluid(BALF) cells were counted.Lung tissue with HE and MCT immunohistochemical staining were used to observe the pathological changes in lung tissue and the distribution of MCT.Results:After injection of different concentration of acetylcholine chloride,the Re in group B and group C were increased significantly compared with group A(P<0.05):compared with group B.the Re in group C were decreased significantly(t=-5.385.-5.761.-6.184.-13.574.P<0.05):the total number of BALF cells and eosinophils were increased significantly in group B and C(t=19.618.9.598.10.854.5.388.P<0.05);compared with group B.the total number of BALF cells and eosinophils in group C was decreased significantly(t=-5.555.-5.392.P<0.05):the number of tryptase positive cells in group B was increased significantly than that in group A(t=21.312,P<0.05),and in addition to the alveolar septum and submucosa,the cells were also distributed around blood vessels and outside the cells:the number of tryptase positive cells in group C was decreased significantly compared with group B.and the difference was statistically significant(t=5.043.P<0.05).Conclusions:After the asthmatic guinea pigs arc treated with 1,25-dihydroxyvitamin D3,their BALF.Re.infiltration degree of inflammatory cells in the trachea and lung tissue and airway inflammatory reaction are reduced significantly.1,25-dihydroxyvitamin D3 has a certain inhibiting effect on the activation of mast cells and the release of MCT granules.

Fracture mechanism of inclusions in thick plate center under tensile loading

Segregation of solute atoms in the center of thick plates of the tempered steel can cause an inhomogeneous structural transformation and generate micron-sized inclusions,which leads to lamellar tearing of thick plate and decreases the plasticity and toughness.The formation and fragmentation mechanisms of micron-sized inclusions,like MnS and(Nb,Ti)C,in the center of thick plates were investigated by using thermodynamic calculations,finite element simulations,and electron backscatter diffraction characterization techniques.The results show that micron-sized inclusions nucleate and grow in the liquid phase,and under tensile loading,they exhibit three fragmentation mechanisms.The local stress during the fragmentation of inclusions is lower than the critical fracture stress of adjacent grains,and phase boundaries can effectively impede crack propagation into the matrix.The existence of a low proportion of high-angle grain boundaries(58.1%)and high Kernel average misorientation value(0.534°)in the segregation band promotes inclusions fragmentation and crack propagation.The difference in crack initiation and propagation direction caused by the morphology of inclusions and physical properties,as well as different matrix arrest abilities,is the main reasons for the diversity of inclusion fragmentation.

Growth Kinetics of Proeutectoid Ferrite in an Fe-0.09C-1.5Mn-0.2Si Steel

Growth kinetics of proeutectoid ferrite, including grain boundary face nucleated ferrite, grain boundary edge nucleated ferrite allotriomorph and intragranular ferrite idiomorph, were experimentally measured in an Fe- 0.09C-1.5Mn-0.2Si steel and compared with theoretical calculation in local equilibrium and paraequilibrium modes. Grain boundary edge nucleated ferrite exhibited larger growth rate than grain boundary face nucleated ferrite and in- tragranular ferrite idiomorph. Experimental kinetics of proeutectoid ferrite was within the window defined by the lo- cal equilibrium and paraequilibrium limits. A transition of growth kinetics from paraequilibrium to local equilibrium was observed in the temperature range of 650--750 ℃, which can be explained in terms of solute drag.