选择性靶动脉栓塞在骶骨肿瘤切除术中的价值

目的 探讨和评估选择性靶动脉栓塞骶骨肿瘤后对外科切除肿瘤的价值和方法。方法 运用Seldinger技术，对9例骶骨肿瘤患者进行肿瘤供血动脉及肿瘤内血管全部彻底栓塞，栓塞材料应用明胶海绵，栓塞后1周内行手术切除术。结果 彻底的术前栓塞手术中失血量明显减少，9例骶骨肿瘤均得到彻底切除，平均失血量为1090ml。术后平均随访15个月，未见肿瘤局部复发。结论 骶骨肿瘤切除术前选择性靶动脉栓塞可有效减少术中出血，有利于肿瘤的彻底切除，为顺利切除骶骨肿瘤提供了有价值的方法。     

电力电缆的预防性试验

主要叙述了电缆做预防性试验及其试验项目、方法和要求，以及需注意的问题。     

宫颈粘液过氧化物酶在月经周期中的变化规律

本文对29例月经周期正常妇女的宫颈粘液过氧化物酶进行了30个周期的研究。在月经周期不同时间测定宫颈粘液过氧化物酶(CMPx)活性及血清促黄体生成素(LH)、雌二醇(E_2)和孕酮(P)。结果表明:在排卵前三天酶活性明显下降,至排卵后一天开始上升。卵泡期,酶活性与E_2呈负相关(r=-0.67);黄体期,酶活性与P呈正相关(r=0.79)。本研究提示:1.CMPx在排卵周期具有特定的变化规律,其变化受体内激素水平影响,可作为预告排卵的指标。2.如简化测定方法,可为自然避孕提供新途径。     

Preparation and characterization of porous beta-tricalcium phosphate/collagen composites with an integrated structure

Porous beta-tricalcium phosphate (TCP)/collagen composites with different beta-TCP/collagen weight ratio were prepared. The influences of the preparation conditions on the microstructure of porous composite and the joint status of beta-TCP particles with collagen fibrils were characterized by X-ray diffractometer, scanning electron microscopy and transmission electron microscopy. The results showed: (1) an acid treatment could effectively disassemble collagen fibrils; (2) in the resulting porous composites, beta-TCP particles homogenously existed on the skeleton of the collagen fibril network and bonded tightly to both the fibrils and themselves. The tight bonding formation could be due to the reaction between Ca ions in the particles and carboxyl groups in collagen polypeptide chains and due to the reprecipitation of partially dissolved beta-TCP during synthesis. The tight bonding between beta-TCP particles and collagen fibrils in the composites demonstrated an integrated structure, which was reproducible when beta-TCP/collagen ratio ranged from 2 to 4. Such integrated structure would make significant contributions in reliably tailoring properties of the porous composites by varying beta-TCP content. In addition, the porous composites had large porosity (approximately 95%) and appropriate pore size (approximately 100 microm), showed no negative impact in cytotoxicity assay and complete bone tissue regeneration after 12 weeks in animal test.     

An orthotopic metastatic prostate cancer model in SCID mice via grafting of a transplantable human prostate tumor line

Metastasis is the major cause of prostate cancer deaths and there is a need for clinically relevant in vivo models allowing elucidation of molecular and cellular mechanisms underlying metastatic behavior. Here we describe the development of a new in vivo model system for metastatic prostate cancer. Pieces of prostate cancer tissue from a patient were grafted in testosterone-supplemented male NOD-SCID mice at the subrenal capsule graft site permitting high tumor take rates. After five serial transplantations, the tumor tissues were grafted into mouse prostates. Resulting tumors and suspected metastatic lesions were subjected to histopathological and immunohistochemical analysis. Samples of metastatic tissue were regrafted in mouse anterior prostates and their growth and spread examined, leading to isolation from lymph nodes of a metastatic subline, PCa1-met. Orthotopic grafting of PCa1-met tissue in 47 hosts led in all cases to metastases to multiple organs (lymph nodes, lung, liver, kidney, spleen and, notably, bone). Histopathological analysis showed strong similarity between orthotopic grafts and their metastases. The latter were of human origin as indicated by immunostaining using antibodies against human mitochondria, androgen receptor, prostate-specific antigen and Ki-67. Spectral karyotyping showed few chromosomal alterations in the PCa1-met subline. This study indicates that transplantable subrenal capsule xenografts of human prostate cancer tissue in NOD-SCID mice can, as distinct from primary cancer tissue, be successfully grown in the orthotopic site. Orthotopic xenografts of the transplantable tumor lines and metastatic sublines can be used for studying various aspects of metastatic prostate cancer, including metastasis to bone.     

Expression of geminin as a marker of cell proliferation in normal tissues and malignancies

Geminin interacts with a DNA replication initiation factor, Cdt1p, to suppress initiation of DNA replication in a Xenopus egg extract based cell-free system, leading to the expectation that the protein acts as an inhibitor of cell proliferation. Immunohistochemistry and immunoblotting for geminin, however, reveals that the protein is expressed specifically in proliferating lymphocytes and epithelial cells. This pattern is in contrast to the expression of a bona fide cell cycle inhibitor like p21/WAF1 that is specifically expressed in quiescent cells. Geminin is widely expressed in several malignancies and the number of geminin-expressing cells is directly proportional to the cell proliferation index as measured by Ki-67 expression. Therefore, instead of being a suppressor of cell proliferation, geminin expression is positively correlated with cell proliferation. Consistent with this observation, transient overexpression of wild-type geminin in cancer cells in culture did not produce a cell cycle block. A point mutation in the destruction box of geminin, however, results in a protein that is stabilized in G(1) and capable of arresting cells at the G(1)-S transition.     

Interaction of hepatitis B surface antigen (Australia antigen) with membrane vesicles of Pseudomonas aeruginosa.

A lysogenic strain of Pseudomonas aeruginosa was cultured from the dialysis fluid of a patient on chronic hemodialysis treatment whose blood contained hepatitis B surface antigen (HB8Ag). When this bacterium was incubated for 4 to 7 days with serum containing HB8Ag or with purified HB8Ag, a loss of the HB8Ag-specific immunological reactivity was observed. Bacteriophages can be induced from the isolated P. aeruginosa with mitomycin C; the phages, after purification on CsCl gradients, also lyse P. aeruginosa strain 25102 (ATCC). Subsequent to gradient centrifugation of the lysate, a fraction was found with a density around 1.40 g/ml that inactivated HB8Ag after a 4-h incubation at 37 C as determined by counterelectrophoresis and hemagglutination inhibition. The activity was not found in appreciable amounts in other gradient fractions. The electron microscope shows that the active fraction contains envelope vesicles of 45 to 60 nm in diameter. In spite of their loss in HB8Ag activity, the HB8Ag particles (22nm) appeared morphologically intact. These findings suggest that an enzyme(s) is present in the vesicle fraction which inactivates antigenic determinants on HB8Ag particles. Thus, the presence of these bacteria in environments such as feces, dialysis tanks, and contaminated drinking water may prevent the detection of HB8Ag.