Dreidimensionale Bildgebung bei Chorioretinopathia centralis serosa

Background

Conventional optical coherence tomography (OCT) has brought new insights to retinal diagnostics, but it is restricted due to its low scanning speed and limited resolution. In this study, high-resolution raster scanning OCT (HR-OCT) was used to identify typical changes in central serous chorioretinopathy (CSC).

Methods

Fifteen consecutive patients with acute CSC were imaged using HR-OCT with an axial image resolution of 6 μm. The scanned area measured 6×6 mm². Three-dimensional (3D) evaluation was performed using various analysing programmes.

Results

Topographic changes in CSC could be visualised with 3D reconstructions in all locations. Retinal thickness was measured with the automatic segmentation mode and quantified precisely. Results were presented in 2D and 3D maps. En-face imaging as a modality to present an integrative overview showed specific alterations in CSC.

Conclusion

HR-OCT was able to provide essential additional information about CSC when combined with appropriate analysing programmes, allowing the identification of typical differences. Aside from precise volumetric measurements, exact localisation of pathological deviations could be achieved.     

Alterations of intraretinal layers in acute central serous chorioretinopathy

Purpose: Optical coherence tomography (OCT) is restricted by its low scanning speed and limited resolution. High‐definition raster‐scanning OCT (HD‐OCT) was used to evaluate changes in retinal microstructure in patients with acute central serous chorioretinopathy (CSCR) and to find new morphological features. Methods: Eighteen patients with subretinal fluid accumulation caused by acute CSCR were imaged in a cross‐sectional study design. High‐speed frequency‐domain HD‐OCT was used to image an area of 6 × 6 mm in the macular retina. Three‐dimensional analyses were performed using en‐face imaging and section analysis of single HD‐OCT scans. Results: Detailed information about fluid accumulation can be obtained in all compartments. Discrete changes in reflectivity are visualized within the outer nuclear or plexiform layers in > 90% of patients. Subretinal fluid appears as a dome‐shaped pool of fluid and is not associated with a loss of photoreceptor layer integrity. Deposits are demarcated beneath the outer cone segments. Multiple small pigment epithelial detachments are present in > 60% of patients. Conclusions: High‐definition OCT provides extensive information regarding precise topographic and layer‐specific localization of discrete morphological changes. Along with well‐known changes in the retinal microstructure, hyper‐reflectivity can be imaged in the outer nuclear or plexiform layers and may represent intraretinal changes indicating the presence of subretinal pathologies or retinal maladjustment caused by the underlying pathology.     

Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos

In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture environment differs from in-vivo conditions in that the oxygen concentration is higher, and in such conditions the mouse embryos show a higher concentration of reactive oxygen species (ROS) in simple culture media. ROS are believed to cause damage to cell membranes and DNA fragmentation in somatic cells. This study was conducted to ascertain the level of H2O2 concentration within embryos and the morphological features of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31 fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was obtained from the IVF-embryo transfer programme. The relative intensity of H2O2 concentrations within embryos was measured using 2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence imaging and DNA fragmentation was observed with transmission electron microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/- SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed only in fragmented embryos, and was absent in non-fragmented embryos. Electron microscopic findings confirmed apoptotic bodies and cytoplasmic condensation in the fragmented blastomeres. We conclude that there is a direct relationship between increased H2O2 concentration and apoptosis, and that further studies should be undertaken to confirm these findings.      

下消化道出血221例分析

0　引言　下消化道出血是消化科的常见病 ,是指十二指肠空肠移行部 ,屈氏韧带以下的小肠和大肠疾病引起的肠道出血 .有人认为一般不包括痔和肛裂出血 [1 ] .临床最常见为慢性出血 ,但有时出血量大危及生命 ,需要做紧急处理 ,现将我院1992 - 0 1/ 1999- 0 8门诊及病房收治的 2 2 1例下消化道出血进行分析 ,报告如下 :1　临床资料　男 12 0例 ,女 10 1例 ,年龄 14～ 72 (平均 42 )岁 ,病程 16 h～ 10 a.患者分别以脓血便、暗红色血便、鲜血便或果酱色血便为主诉前来就诊 ,其中有休克症状的大出血者6例 .血 Hb<110 g·L- 1 40例 ,<80 g·L- 1…     

Expression and characterization of Gag protein of HIV-1（CN） in Pichia pastoris

To express the core protein of HIV-1 of Chinese prevalent strain （HIV-1 （CN）） in Pichia pastoris, the fulllength gag gene was inserted into the secretory expression vector pHILS1. Linearized recombinant plasmid pHILGAG by Sail was electrotransformed into the yeast strain GS115, and the yeast transformants were identified by PCR. To induce the interest protein to be expressed, the PCR positive transformants were inoculated in the medium of BMGY and BMMY, mRNA of the strain was detected by RT-PCR, and the expressed protein was analyzed by SDS-PAGE, Western blotting and thin layer scanning. mRNA （1.3 kb） was amplified by RT-PCR. SDS-PAGE and Western blotting analysis showed that the molecular mass of the expressed protein was 55 kD, which was similar to the expected value, and the expressed protein could react with McAb to HIV-1 p24. Thin layer scanning analysis demonstrated that the whole amount of the expressed protein was approximately 13 % of the soluble protein in the supernatant. The recombinant yeast had good genetic stability. The optimal expression conditions of the engineering yeast were as follows： BMMY medium, 80-90% of dissolved oxygen, 1% methanol, and 3-day-cultivation course. Gag proteins were expressed under the optimal expression condition and purified via gel filtration chromatography. The purity of the interest protein was up to 85 %. After the purified proteins were inoculated into BALB/c mice, the anti-HIV-1 antibodies in the immunized mice could be detected by Western blotting.     

Die Drahtzuggurtungsosteosynthese—Untersuchungen zu Spannung und Fixierung des Osteosynthesedrahtes

In tension band wiring different tensioners and wire-connection are in use. Both of these were examined on tensile force during and after connection with help of a material-testing machine. Additionally the different connections were examined under traction-load. The results show that none of the tensioners for monofilament wire are capable of establishing a permanent tension at the end of the fixation-procedure. Consequently we must ask if the theoretical principle of B. G. Weber concerning tension band wiring is efficient in practice. Only the use of twisted wires in combination with fixation clamps could produce a permanent tension. The limit of elasticity is 2 to 3% for monofilament wires as well as for twisted wires. Further stretching causes plastic, i. e. irreversible deformation in monofilament wire and its connections. In twisted wires further tension stress causes ruptures especially at the border of the fixation clamp. In conclusion extreme active exercise of fructures treated with tension band wiring should not be emphasized.     

Kinematics of the patellofemoral joint

Summary Patellofemoral kinematics were studied on a computer model. The articulating point of the patella moves from distal to proximal during flexion, until the quadriceps tendon starts to turn around the femur tendofemoral gliding. The pattern of patellofemoral movement consists of a gliding and rolling component, the latter at its maximum at the beginning of flexion. The pathway of the instant centers of motion moves from dorsal to ventral during flexion. Stress analysis shows that the contact area is at all times the area of maximum bending stress. The distal part of the patella is the part with mechanical stress at all angles of flexion. The conclusions to be drawn for treatment are that fractures within the proximal and central part of the patella need a very high stability of internal fixation, the distal part of the patella less so. Postoperative treatment must take into account the changing contact area, because the peak stress is always at the contact area.     

精液分析现状：对《亚洲男性学杂志》出版的陆金春等所著的“中国118家实验室精液分析状况的调查”一文的评论

陆金春等^[1]所著的“中国118家实验室精液分析状况的调查”一文主要回顾了当前在中国采用的精液分析方法。调查使用的是作者自己设计的包括36个问题的“男科实验室精液分析调查表”。给145家精液实验室发放了调查表,收回118份答卷。调查表均由实验室专业技术人员填写。