一种小鼠肿瘤相关膜蛋白单抗对DCS细胞生物学行为的影响

探讨一种小鼠肿瘤相关膜蛋白在ＤＣＳ细胞表达的意义。方法用该蛋白抗处理ＤＣＳ细胞,观察其对细胞生长速度,软琼脂克隆形成能力,粘附性,细胞运动能力,水解酶活性,侵袭性,体内转移率等生物学行为方面的影响。结论该细胞膜蛋白可能调控小鼠肿瘤细胞增殖能力。     

The effect of a levonorgestrel-releasing intrauterine device on human endometrial oestrogen and progesterone receptors after one year of use

Thirty-four women bearing a levonorgestrel-releasing intrauterine device, 20 micrograms/day (LNG-IUD-20), for 12-15 months were recruited. Endometrial biopsies were collected during the late proliferative phase of the cycle (on cycle days 10-12) before (control) and after the use of the IUD for 12 months, and assayed for oestrogen receptors (ER) and progesterone receptors (PR). An immunohistochemical technique with the peroxidase-antiperoxidase detection system (PAP method) was employed. D75 and JZB39 were the primary antibodies for ER and PR respectively. The immunostaining semiquantitative analysis was performed with a computerized microscope image processor, and expressed as 'grey value'. Both endometrial ER and PR populations were significantly lower after insertion of the IUD (P < 0.01) than in control biopsies. The intensity of nuclear staining and the percentage of positively stained cells for ER and PR in women with LNG-IUD were each about 50% of those in control biopsies. The results suggested that LNG released locally from the IUD has a depressive action on the ER and PR, which may contribute to the contraceptive effectiveness of this type of IUD and also to the possible causes of LNG-IUD-induced irregular bleeding and amenorrhoea.     

Frequency of the fragile X syndrome in Chinese mentally retarded populations is similar to that in Caucasians.

Fragile X syndrome is recognized as the most common inherited cause of mental retardation in western countries. The prevalence of the fragile X syndrome in Asian populations is uncertain. We report a multi-institutional collaborative study of molecular screening for the fragile X syndrome from 1,127 Chinese mentally retarded (MR) individuals. We found that 2.8% of the Chinese MR population screened by DNA analysis had the fragile X full mutation. Our screening indicated that the fragile X syndrome prevalence was very close to that of Caucasian subjects. In addition, we found that 62.5% of fragile X chromosomes had a single haplotype for DXS548-FRAXAC1 (21-18 repeats) which was present in only 9.7% of controls. This unique distribution of microsatellite markers flanking the FMR1 CGG repeats suggests that the fragile X syndrome in Chinese populations, as in the Caucasian, may also be derived from founder chromosomes.     

Reconstructed human cornea produced in vitro by tissue engineering.

The aim of the present study was to produce a reconstructed human cornea in vitro by tissue engineering and to characterize the expression of integrins and basement membrane proteins in this reconstructed cornea. Epithelial cells and fibroblasts were isolated from human corneas (limbus or centre) and cultured on plastic substrates in vitro. Reconstructed human corneas were obtained by culturing epithelial cells on collagen gels containing fibroblasts. Histological (Masson's trichrome staining) and immunohistological (laminin, type VII collagen, fibronectin as well as beta1, alpha3, alpha4, alpha5, and alpha6 integrin subunits) studies were performed. Human corneal epithelial cells from the limbus yielded colonies of small fast-growing cells when cultured on plastic substrates. They could be subcultured for several passages in contrast to central corneal cells. In reconstructed cornea, the epithelium had 4-5 cell layers by the third day of culture; basal cells were cuboidal. The basement membrane components were already detected after 3 days of culture. Integrin stainings, except for the alpha4 integrin, were also positive after 3 days. They were mostly detected at the epithelium-stroma junction. Such in vitro tissue-engineered human cornea, which shows appropriate histology and expression of basement membrane components and integrins, provides tools for further physiological, toxicological and pharmacological studies as well as being an attractive model for gene expression studies.     

Preparation of three functional monoclonal antibodies against human FL molecule and analysis of their bioactivity]

AIM: To Prepare three functional monoclonal antibodies(mAbs) against human FL molecule and analyze their bioactivity. METHODS: The cell line L929-FL transfected with human FL gene was used as immunogen. The hybridomas secreting the antibodies against human FL were obtained by fusing splenoecytes from the immunized mice with murine myeloma cells(Sp2/0). Their subclasses were analyzed using fast-strip method. The monoclonal antibodies were produced in mouse peritoneal cavity and purified by Protein G affinity chromatography. The inhibitory effect of mAbs against FL on leukemia cell lines U937 and HL-60 was detected by MTT. The apoptosis of U937 and HL-60 cells stained by annexin-V/PI was determined by FCM. RESULTS: Three hybridomas named 3C2, 3C6 and 8D10 were successfully obtained, which secreted monoclonal antibodies against human FL molecule stably. Their subclasses were the mouse IgG2a with kappa light chains. The three monoclonal antibodies recognized the FL molecule on U937 and HL-60 cells that also coexpressed Flt3 molecule. When U937 and HL-60 cells were cultured in presence of 3C2, 3C6 and 8D10, their proliferation was reduced as compared to that in control in MTT assay(P < 0.05). The analysis of annexin-V/PI binding to U937 and HL-60 cells by FCM showed the mAbs had the apoptotogenic activity of the monoclonal antibodies against human FL molecule. CONCLUSION: 3C2, 3C6 and 8D10 are three funtional monoclonal antibodies against human FL molecule. They may be of some value in the study of the roles of FL/Flt3 interaction in leukemia pathogenesis.     

DNA repair gene XRCC1 and XPD polymorphisms and the risk of idiopathic azoospermia in a Chinese population

Genetic polymorphisms in DNA repair genes may influence individual variation in DNA repair capacity and further influence the risk of developing cancer. However, little information is available on these polymorphisms in infertility. To investigate whether polymorphisms in DNA repair genes, X-ray repair cross-complementing group 1 (XRCC1) and xeroderma pigmentosum group D (XPD), alone or in combination, are associated with the risk of developing idiopathic azoospermia, the genotype and allele frequencies of three observed polymorphisms (XRCC1 Arg194Trp and Arg399Gln, and XPD Lys751Gln) were examined by polymerase chain reaction-restriction fragment length polymorphism based on a Chinese population consisting of 171 idiopathic azoospermia patients and 247 normal-spermatogenesis fertile controls. Associations between the polymorphisms and the idiopathic azoospermia risk were estimated by logistic regression, and the Statistical analysis system was used to test the gene-gene joint effects. All observed polymorphisms were in agreement with Hardy-Weinberg equilibrium. The XPD 751Gln allele seemed to be a risk allele for azoospermia, with a frequency of 11.40% in the cases and 5.67% in the controls (p=0.004). Compared with the Lys/Lys genotype, the XPD 751 Lys/ increased 5.100- or 3.064-fold, respectively, when combined with the XRCC1 194 Arg/Arg or 399 Arg/Arg genotype. In conclusion, our study provided the first evidence that the XPD and XRCC1 polymorphisms contributed to the risk of developing idiopathic azoospermia in a selected Chinese population.     

A functional link between area MSTd and heading perception based on vestibular signals

Recent findings of vestibular responses in part of the visual cortex--the dorsal medial superior temporal area (MSTd)--indicate that vestibular signals might contribute to cortical processes that mediate the perception of self-motion. We tested this hypothesis in monkeys trained to perform a fine heading discrimination task solely on the basis of inertial motion cues. The sensitivity of the neuronal responses was typically lower than that of psychophysical performance, and only the most sensitive neurons rivaled behavioral performance. Responses recorded in MSTd were significantly correlated with perceptual decisions, and the correlations were strongest for the most sensitive neurons. These results support a functional link between MSTd and heading perception based on inertial motion cues. These cues seem mainly to be of vestibular origin, as labyrinthectomy produced a marked elevation of psychophysical thresholds and abolished MSTd responses. This study provides evidence that links single-unit activity to spatial perception mediated by vestibular signals, and supports the idea that the role of MSTd in self-motion perception extends beyond optic flow processing.     

正常踝关节内、外侧韧带的解剖及其影像学表现

目的:探讨正常踝关节内、外侧韧带的解剖形态及其MRI和CT表现。方法:6例正常人踝关节新鲜标本MRI扫描,解剖显示内、外侧韧带后,CT断层扫描与MRI对照观察踝关节内、外侧韧带的影像学表现;在30例正常志愿者踝关节的MRI上测量内、外韧带的宽度及厚度。结果:MRI横断面及冠状面可充分显示踝关节内、外侧韧带及其周围组织的解剖结构;踝关节内、外侧韧带在冠状面及横断面上所测的宽、厚度,男女间存在一定的差异。结论:MRI能清晰地显示踝关节的解剖结构,所测量的正常踝关节内、外侧韧带的宽、厚度数据,为临床诊断踝关节内、外侧韧带的病变提供了形态学依据。     

DSA图像中运动伪影的消除方法

由于病人存在着各种运动(如呼吸、肌肉运动、心脏运动、设备噪声),在成像过程中常会造成图像上出现伪影,干扰医生的正常诊断,为消除这种伪影,本文提出一种基于图像配准思想的全自动消除伪影的方法,该方法能够自动消除DSA图像中的大部分运动伪影,使DSA图像得到较好的增强,并为后面的血管分割和三维重建提供便利,是一种快速有效的方法.