Trends and predictions for gastric cancer mortality in Brazil

AIM: To analyze the effect of age-period and birth cohort on gastric cancer mortality, in Brazil and across its five geographic regions, by sex, in the population over 20 years of age, as well as make projections for the period 2010-2029.METHODS: An ecological study is presented herein,which distributed gastric cancer-related deaths in Brazil and its geographic regions. The effects of ageperiod and birth cohort were calculated by the Poisson regression model and projections were made with the age-period-cohort model in the statistical program R. RESULTS: Progressive reduction of mortality rates was observed in the 1980's, and then higher and lower mortality rates were verified in the 2000's, for both sexes, in Brazil and for the South, Southeast and Midwest regions. A progressive decrease in mortality rates was observed for the Northeast(both sexes) and North(men only) regions within the period 1995-1999, followed by rising rates. CONCLUSION: Regional differences were demonstrated in the mortality rates for gastric cancer in Brazil, and the least developed regions of the country will present increases in projected mortality rates.     

胸腺瘤临床病理的预后因素研究

目的 探讨胸腺瘤临床病理特点与预后的关系。方法 对130例胸腺瘤的重症肌无力、肿瘤大小、坏死、核分裂及包膜情况、组织学分型（按照L－B分类及M－H分类）、Massaoka临床分期等诸多因素进行分析,观察其5,10年生存率的差别,所得数据进行统计学U检验及χ^2检验。结果 重症肌无力的有无、肿瘤大小、坏死、核分裂及L－B分类均与预后无关（P＞0．05）;而肿瘤有无包膜、M－H分类及临床分期与生存率有明显相关性。有包膜者5,10年生存率分别为100％和93．1％,无包膜者分别为54．4%和40．0％（P＜0．05）。按M－H分类,髓质型5,10年生存生存率分别为100％和79．8％,混合型分别为97．5％和88．4％,皮质为主型分别为83．3％和50．1％,皮质型分别为60．2％和29．9％,分化好的胸腺癌（WDTC）分别为43．4％和0％（P＜0．05）。临床分期中Ⅰ期5,10年生存率分别为100％和93．2％,Ⅱ期分别为84．6％和78．4％,Ⅲ期分别为45．3％和19．8％,Ⅳ期分别为38．0％和0（P＜0．01）。其中以细胞的异型性及有无侵犯胸腺周围器官对预后尤为重要。结论 L－B分类与预后无关;M－H分类、临床分期与预后有关,尤其是瘤细胞呈多角形和大圆形、临床侵犯胸腺外器官者对预后影响较明显。     

Maternal hyperphenylalaninaemia as a cause of microcephaly and mental retardation

We attempted to evaluate the role of maternal hyperphenylalaninaemia (HPA) as an isolated cause of mental retardation and microcephaly in children. This transversal study observed the plasma phenylalanine from mothers of 161 children with mental retardation and/or microcephaly of unknown origin. In this sample, we found two women with previously undiagnosed HPA, a frequency (2/161) higher than expected for our general population (1:12 500) ( p < 0.001). We concluded that the plasma phenylalanine levels should be determined during preconceptional evaluation of every woman of reproductive age that already has had a child affected either by mental retardation or microcephaly of unknown cause. It is particularly significant where women currently having their pregnancies have not been screened for phenylketonuria as newborns, as happens in most developing countries.     

Lack of a co-promoting effect of a 60 Hz magnetic field on skin tumorigenesis in SENCAR mice

It has been proposed that extremely low frequency (ELF) magnetic fields may enhance tumorigenesis through a co-promotional mechanism. This hypothesis has been further tested using the two-stage model of mouse skin carcinogenesis, i.e. 12-O-tetradecanoylphorbol-13-acetate (TPA)- induced promotion of skin tumors in mice initiated by a single subcarcinogenic dose of 7,12-dimethylbenz[a]anthracene. Experimentation described herein utilized the SENCAR mouse and examined the effect of a magnetic field on skin tumor promotion induced by three different doses of TPA within its dose-response range, i.e. 0.85, 1.70 or 3.40 nmol, administered twice per week. SENCAR mice (56/treatment group) were exposed to a 60 Hz magnetic field having a flux density of 2 mT for 6 h/day for 5 days/week and compared with mice exposed to the ambient magnetic field. Tumor incidence and multiplicity were monitored weekly for 23 weeks of TPA promotion. Statistical evaluation of the effects of the magnetic field on tumor incidence and multiplicity did not reveal any statistically significant effects; thus, within the sensitivity limits imposed by the animal model and the exposure parameters employed, no promotional or co-promotional effect of a 2 mT magnetic field on skin tumor development in SENCAR mice could be demonstrated.      

三种阳离子脂质体介导血管内皮细胞基因转染效率的比较

目的:评价不同阳离子脂质体介导基因转染血管内皮细胞的转染效率。方法:实验于2006-12/2007-02在中山大学生化实验室及广州市创伤外科研究所完成。采用增强型绿色荧光蛋白基因为报告基因,分别采用Lipofectin、Lipofectamine、Dosper3种不同的阳离子脂质体为载体,转染人脐静脉血管内皮细胞。在24孔板中,每孔加入人脐静脉血管内皮细胞悬液(1×106个细胞),各孔分别加入3种不同阳离子脂质体增强型绿色荧光蛋白质粒复合物,分别于培养24,48h后用荧光显微镜及流式细胞仪测定增强型绿色荧光蛋白在细胞内的表达及转染效率。结果:3种不同阳离子介导的增强型绿色荧光蛋白基因转染的人脐静脉血管内皮细胞内均有绿色荧光蛋白表达,24h后明显,48h后达高峰。Dosper介导组绿色荧光细胞百分比明显高于Lipofectin介导组及Lipofectamine介导组,差异有非常显著意义(P<0.01)。结论:Dosper介导的血管内皮细胞基因转染效率较高,较适合作为血管内皮细胞的基因转染载体。     

Multiple unconfirmed-reactive screening tests for viral antibodies among blood donors

BACKGROUND: In December 1991, the United States Food and Drug Administration received reports of blood donations with unconfirmed reactivity on screening tests for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus (HCV). Of 91 donors with these test results, 57 (63%) reported a recent influenza vaccination. STUDY DESIGN AND METHODS: To determine the extent of unconfirmed reactivity, the time at which it began, and its association or nonassociation with specific manufacturers' tests, a nationwide survey of blood centers was conducted. A case-donation was defined as a blood donation that was repeatedly reactive, but not confirmed positive, on at least two of the three tests from May 1990 through December 1991. RESULTS: Among 14 million donations screened by 110 centers, 582 case-donations were identified. An increase in case- donations was evident in the fall of 1990 (2.8/100,000 donations). In 1991, rates increased from 0.9 per 100,000 donations in the first quarter to 1.3, 3.2, and 19.7 in subsequent quarters. A significantly higher rate of case-donations was observed among donations tested with one of the two available anti-HCV screening tests (8.0 vs. 1.2/100,000 donations; risk ratio = 6.8; 95% CI = 5.4-8.5). CONCLUSION: Although unconfirmed reactivity on multiple screening tests appeared to be seasonal, its documentation prior to the availability of influenza vaccine in 1991 and higher rates among donations tested with one manufacturer's anti-HCV test indicated that test-specific factors were also involved.     

成人骨髓间充质干细胞的体外培养及生物学特性

目的:观察成人骨髓间充质干细胞体外分离培养方法及其生物学特性,为骨髓间充质干细胞的临床应用奠定技术基础。方法:实验于2005-12在吉林省四平市中心医院中心实验室进行。实验材料:人骨髓间充质干细胞,Ficoll淋巴细胞分离液,胎牛血清,牛血清白蛋白,α-MEM培养基,胰蛋白酶,FITC标记的CD44和CD90。实验方法:①人骨髓间充质干细胞的分离与培养:采集成人骨髓,密度梯度法分离单个核细胞,条件培养基培养和扩增,倒置光学显微镜下观察细胞形态及生长情况。②人骨髓间充质干细胞生长曲线的测定:取生长良好的P1,P5,P10细胞,用胰酶消化,接种于24孔板培养,每天各取3孔消化计数细胞,取平均值,连续培养7d,绘制生长曲线。③人骨髓间充质干细胞表面标志的测定:取生长良好P5细胞进行免疫荧光染色鉴定(CD44,CD90并设同型对照)。④人骨髓间充质干细胞的冻存及复苏:收集生长良好细胞,计数细胞密度及冻前存活率。将细胞加入到细胞冻存液中液氮冷冻保存。30d后复苏细胞,每日倒置光学显微镜下观察细胞生长状况。结果:①倒置显微镜下观察细胞形态:倒置显微镜下观察细胞呈纤维形,漩涡状生长。②人骨髓间充质干细胞的生长曲线分析:传代的细胞生长较原代要快,从第10代开始细胞生长开始出现缓慢征象。③细胞表面标记检测结果:免疫荧光染色后细胞膜着色明显,CD44,CD90阳性率均大于90%。④细胞冻存及复苏生长特性分析:椎虫蓝计数细胞存活率90%以上,增殖能力强,和未冻存过的传代细胞具有同样的生长特性。结论:应用密度梯度法分离法能获得较高纯度的骨髓间充质干细胞,能在体外长期培养,在传代培养5代内生长旺盛且生物学特性稳定。     

Purging murine leukemic marrow with alkyl-lysophospholipids

Autologous bone marrow transplantation is potentially curative in the treatment of acute leukemia if residual leukemic cells in the marrow can be eliminated prior to transplantation. We studied the purging effects of a synthetic alkyl-lysophospholipid (ALP) on marrow containing leukemic cells from a transplantable myelomonocytic leukemia (WEHI-3B) in BALB/c mice. Simulated remission bone marrow containing 2% leukemic cells treated in vitro with 20 and 100 micrograms/mL of ET-18- OCH3 (1-octadecyl-2-methyl-sn-glycerol-3-phosphocholine) significantly prolonged survival of lethally irradiated transplanted recipients. At a dose of 100 micrograms/mL, 88% of the mice survived for the duration of the experiment (approximately five months). Autopsies showed that 25% of these survivors had microscopic evidence of leukemia. Thus, in vitro treatment of marrow eliminated leukemic blasts and spared sufficient normal stem cells to allow hematologic reconstitution. The effect of ET- 18-OCH3 is not entirely selective for leukemic cells. A spleen colony assay showed that ALP has some cytotoxic effect on normal hematopoietic stem cells.     

Extruded erythroblast nuclei are bound and phagocytosed by a novel macrophage receptor

Resident bone marrow macrophages (RBMM) play an important role in clearance of nuclei extruded from late-stage erythroblasts (Eb). To investigate the nature of macrophage receptors involved in this process, extruded erythroblast nuclei (EEN) were purified by cultivation of erythroblasts with erythropoietin, followed by density gradient centrifugation. By electron microscopy, the majority of free nuclei had an intact plasma membrane. EEN bound avidly to RBMM in a divalent cation-independent manner at both 4 degrees C and 37 degrees C. The use of specific monoclonal antibodies (MoAbs) and inhibitors showed that this adhesive interaction was not mediated by previously characterized macrophage receptors involved in recognition of either developing hematopoietic cells or apoptotic cells. The EEN receptor was expressed on resident macrophages isolated from murine bone marrow, spleen, lymph node, and peritoneal cavity, but was completely absent from alveolar macrophages. Despite high levels of EEN binding to RBMM, few were phagocytosed even after prolonged culture. Phorbol myristate acetate (PMA) was found to stimulate phagocytosis, suggesting that this is a regulated process. These findings indicate that EEN are recognized by a novel macrophage receptor and that recognition may be triggered during the membrane remodeling that accompanies enucleation.