糖皮质激素对大鼠肾上腺嗜铬细胞分泌儿茶酚胺的急性效应

利用全细胞膜片钳技术,观察不同浓度地塞米松急性灌洗大鼠肾上腺嗜铬细胞(AMCC)后钙通道电流和烟碱受体通道电流(INIC)的变化,地塞米松对大鼠AMCC的急性作用为明显抑制INIC而对电刺激所诱发的钙通道电流无明显影响,提示糖皮质激素对大鼠AMCC分泌儿茶酚胺的急性效应可能与烟碱受体直接相关。     

阿托伐他汀对不稳定型心绞痛患者树突状细胞功能的影响

目的 研究不稳定型心绞痛患者(UAP)树突状细胞(DC)的功能及阿托伐他汀对其的影响。方法 将27例UAP分为常规治疗组(12例)和常规加阿托伐他汀治疗组(15例),分别于治疗前及治疗后2周取血分离外周血单个核细胞,在含粒细胞巨噬细胞集落刺激因子和白细胞介素(IL)4的培养条件下制备DC。用流式细胞仪检测DC表面共刺激分子CD86(B7-2)的表达;混合淋巴细胞反应(MLR)检测DC对同种异体T淋巴细胞的刺激能力;ELISA法测定MLR上清液中的细胞因子;探讨CD86表达与冠心病危险因素及C反应蛋白(CRP)的相关性。结果 与正常对照组比较,UAP者DC表面CD86的表达明显增高;对T淋巴细胞刺激的能力增强;经DC刺激的淋巴细胞分泌致炎细胞因子(IL-1β,IL-6,肿瘤坏死因子α)增多,抑炎细胞因子(IL-10)减少;用药前CD86的表达与血LDL-C水平正相关;阿托伐他汀抑制DC功能的同时显著降低血CRP水平;且CD86与CRP水平正相关。结论 (1)UAP者DC的功能亢进,由此启动的T淋巴细胞的增殖和炎性细胞因子分泌可能是UAP者动脉斑块不稳定的原因,(2)LDL-C可能是其刺激因素;(3)阿托伐他汀抑制斑块炎症的机制之一是其对DC的抑制。     

Inhibitory effect of interferon-α-2b on expression of cyclooxygenase-2 and vascular endothelial growth factor in human hepatocellular carcinoma inoculated in nude mice

AIM： To evaluate the effects of interferon-α-2b （IFN- α-2b） on expression of cyclooxygenase-2 （COX-2） and vascular endothelial growth factor （VEGF） in human hepatocellular carcinoma （HCC） inoculated in nude mice and to study the underlying mechanism of IFN-α- 2b against HCC growth. METHODS： Thirb/-two nude mice bearing human HCC were randomly divided into four groups （n = 8）. On the 10th day after implantation of HCC cells, the mice in test groups （groups A, B and C） received IFN-α- 2b at a serial dose （10000 IU for group A, 20000 IU for group B, 40000 IU for group C sc daily） for 35 d. The mice in control group received normal saline （NS）. The growth conditions of transplanted tumors were observed. Both genes and proteins of COX-2 and VEGF were detected by RT-PCR and Western blot. Apoptosis of tumor cells in nude mice was detected by TUNEL assay after treatment with IFN-α-2b. RESULTS： Tumors were significantly smaller and had a lower weight in the IFN-α-2b treatment groups than those in the control group （P 〈 0.01）, and the tumor growth inhibition rate in groups A, B and C was 27.78%, 65.22% and 49.64%, respectively. The expression levels of both genes and proteins of COX-2 and VEGF were much lower in the IFN-α-2b treatment groups than in the control group （P 〈 0.01）. The apoptosis index （AI） of tumor cells in the IFN-α-2b treatment groups was markedly higher than that in the control group （P 〈 0.01）. Group B had a higher inhibition rate of tumor growth, a lower expression level of COX-2 and VEGF and a higher AI than groups A and C （P 〈 0.05）, but there was no significant difference between groups A and C. CONCLUSION： The inhibitory effects of IFN-α-2b on implanted tumor growth and apoptosis may be associated with the down-regulation of COX-2 and VEGF expression. There is a dose-effect relationship. The medium dose of IFN-α-2b for inhibiting tumor growth is 20 000 IU/d.     

花生四烯酸细胞色素P450表氧化酶代谢产物EET促进血管生成的研究

目的研究花生四烯酸细胞色素P450（cytochrome P450,CYP）表氧化酶代谢产物表氧二十碳三烯酸（epoxyeicosatrienoic acid,EET）对牛主动脉内皮细胞（bovine endothelial cells,BAEC）、对血管生成的影响及其机制.方法分离BAEC培养,给予外源性EET刺激、重组腺相关病毒介导的各种CYP表氧化酶（CYP2J2,CYP2C11,CYPF87V）转染后,采用细胞计数、噻唑蓝比色法检测细胞增殖改变,用流式细胞仪检测对细胞增殖周期的影响,同时检测细胞趋化移行的改变,比较对Matrigel中毛细血管样结构形成的影响,观察表氧化酶过度表达对鸡胚尿囊绒毛膜血管生成和大鼠缺血后肢毛细血管生成的影响.结果各种EET刺激或表氧化酶病毒转染均显著促进BAEC的增殖、趋化和移行,并使Matrigel中毛细血管样结构的形成明显增加,且EET呈剂量依赖性效应,而合用一氧化氮合酶抑制剂、丝裂原激活的蛋白激酶（mitogen-activated protein kinase,MAPK）抑制剂或磷脂酰肌醇-3激酶（phosphatidylinositol 3-kinase,PI3K）抑制剂均可显著抑制上述效应,另外表氧化酶病毒转染尚能明显促进CAM小血管和大鼠缺血后肢毛细血管的生成.结论花生四烯酸细胞色素P450（CYP）表氧化酶及其代谢产物EET可显著促进血管的生成,可改善局部组织的缺血,其作用由MAKP和PI3K介导,部分效应由其对一氧化氮的上调作用介导.     

Dual-slit confocal light sheet microscopy for in vivo whole-brain imaging of zebrafish

In vivo functional imaging at single-neuron resolution is an important approach to visualize biological processes in neuroscience. Light sheet microscopy (LSM) is a cutting edge in vivo imaging technique that provides micron-scale spatial resolution at high frame rate. Due to the scattering and absorption of tissue, however, conventional LSM is inadequate to resolve cells because of the attenuated signal to noise ratio (SNR). Using dual-beam illumination and confocal dual-slit detection, here a dual-slit confocal LSM is demonstrated to obtain the SNR enhanced images with frame rate twice as high as line confocal LSM method. Through theoretical calculations and experiments, the correlation between the slit’s width and SNR was determined to optimize the image quality. In vivo whole brain structural imaging stacks and the functional imaging sequences of single slice were obtained for analysis of calcium activities at single-cell resolution. A two-fold increase in imaging speed of conventional confocal LSM makes it possible to capture the sequence of the neurons’ activities and help reveal the potential functional connections in the whole zebrafish’s brain.OCIS codes: (180.2520) Fluorescence microscopy, (110.0110) Imaging systems, (170.3880) Medical and biological imaging, (170.2945) Illumination design, (180.1790) Confocal microscopy     

Hepatic Angiomyolipomas: Ultrasonic Characteristics of 25 Patients from a Single Center

Twenty-five pathologically proven hepatic angiomyolipomas (AMLs) were included in the study. Ultrasonic features of hepatic AMLs were reviewed. Three types of echogenicity were observed on ultrasound examination: (i) strong hyper-echogenicity, (ii) moderate hyper-echogenicity and (iii) hypo-echogenicity. Vascular signals within tumors could be detected in 22 (88.00%) tumors as multiple punctiform, filiform or dendriform signals by color Doppler flow imaging. Based on the enhancement patterns in the arterial, portal and late phases, the features of hepatic AMLs on contrast-enhanced ultrasound were divided into four subtypes: (i) “fast in slow out” (68.00%, n = 17); (ii) “fast in same out” (16%, n = 4); (iii) “fast in fast out” (12.00%, n = 3); and (iv) “fast in uneven out” (4.00%, n = 1). Contrast-enhanced ultrasound diagnosed 22 (88.00%) tumors as benign tumors and 13 (52.00%) as hepatic AMLs. Four cases were misdiagnosed as hepatic hemangioma, five cases as focal nodular hyperplasia (total = 36.00%). The rate of correct diagnosis of hepatic AMLs increased significantly from 24.00% for ultrasound alone to 52.00% for contrast-enhanced ultrasound. Therefore, information obtained from ultrasound, color Doppler flow imaging and contrast-enhanced ultrasound should be combined to improve diagnosis.     

Diagnosis of Thyroid Nodules Using Virtual Touch Tissue Quantification Value and Anteroposterior/Transverse Diameter Ratio

This paper proposes an effective approach to differential diagnosis of thyroid nodules using a hierarchical classification model based on the Virtual Touch tissue quantification (VTQ) value and anteroposterior/transverse diameter (A/T) ratio. One hundred twenty nodules (92 benign, 28 malignant) were analyzed using this approach by combining the quantitative elastic characteristic with the conventional sonographic feature. First, nodules were classified as benign (VTQ values <2.27 m/s), malignant (VTQ values >2.73 m/s) and indeterminate (2.27 m/s ≤ VTQ values ≤2.73 m/s) using two cutoff points selected on the basis of receiver operating characteristic analysis. Second, the indeterminate nodules were separated into malignant and benign nodules using an A/T ratio ≥1. The advantage of this approach was that it could alleviate the limitation of an overlap in VTQ values between benign and malignant nodules. According to the pathologic results, the accuracy of this approach was 95%. The proposed approach may potentially improve diagnostic accuracy.     

Effect of transient scrotal hyperthermia on sperm parameters,seminal plasma biochemical markers,and oxidative stress in men

In this experimental prospective study, we aimed to analyze the effect of transient scrotal hyperthermia on the male reproductive organs, from the perspective of sperm parameters, semen plasma biochemical markers, and oxidative stress, to evaluate whether different frequencies of heat exposure cause different degrees of damage to spermatogenesis. Two groups of volunteers (10 per group) received testicular warming in a 43°C water bath 10 times, for 30 min each time: group 1: 10 consecutive days; group 2: once every 3 days. Sperm parameters, epididymis and accessory sex gland function, semen plasma oxidative stress and serum sex hormones were tested before treatment and in the 16-week recovery period after treatment. At last, we found an obvious reversible decrease in sperm concentration (P = 0.005 for Group 1 and P= 0.008 for Group 2 when the minimums were compared with baseline levels, the same below), motility (P = 0.009 and 0.021, respectively), the hypoosmotic swelling test score (P = 0.007 and 0.008, respectively), total acrosin activity (P = 0.018 and 0.009, respectively), and an increase in the seminal plasma malondialdehyde concentration (P = 0.005 and 0.017, respectively). The decrease of sperm concentration was greater for Group 2 than for Group 1 (P = 0.031). We concluded that transient scrotal hyperthermia seriously, but reversibly, negatively affected the spermatogenesis, oxidative stress may be involved in this process. In addition, intermittent heat exposure more seriously suppresses the spermatogenesis compared to consecutive heat exposure. This may be indicative for clinical infertility etiology analysis and the design of contraceptive methods based on heat stress.