内皮抑素转基因治疗裸鼠人肝癌的实验研究

目的构建表达人内皮抑素的重组真核表达载体,研究阳离子脂质体介导转染内皮抑素基因对裸鼠人肝癌生长的抑制作用。方法将含有IL-2信号肽和人内皮抑素基因全长cDNA插入真核表达载体pcDNA3.0产生重组质粒pCD-sEndo,脂质体Dosper介导将pCD-sEndo质粒转染至人肝癌细胞株SMMC-7721,RT-PCR和Western blot检测内皮抑素的表达。建立裸鼠人肝癌模型,按随机数字表法随机分成4组,分别瘤内注射Dosper+pCD-sEndo(Dosper+pCD-sEndo组)、Dosper+pcDNA3.0(Dosper+pcDNA3.0组)、Dosper(Dosper组)和生理盐水(生理盐水组),分时段测量肿瘤的体积;注射结束后1周处死动物,切取肿瘤,免疫组化检测肿瘤组织微血管密度(MVD),TUNEL染色检测肿瘤细胞凋亡指数(AI)。结果成功构建携带人内皮抑素基因和IL-2信号肽的真核表达质粒pCD-sEndo并经酶切鉴定证实;体外转染内皮抑素基因的SMMC-7721细胞,RT-PCR可以检测到内皮抑素mRNA表达,Western blot显示转染细胞培养液中有内皮抑素蛋白表达,而转染空白质粒者中没有;体内实验中,Dosper+pCD-sEndo组裸鼠肿瘤生长受抑,于第12 d起明显小于Dosper+pcDNA3.0组、Dosper组和生理盐水组(P<0.05)。Dosper+pCD-sEndo组平均MVD为6.2±2.5,明显低于生理盐水组(32.8±6.4)、Dosper组(27.8±6.4)和Dosper+pcDNA3.0组(25.5±5.5),P<0.05;Dosper+pCD-sEndo组肿瘤细胞平均AI为24.5±7.3,生理盐水组、Dosper组和Dosper+pcDNA3.0组分别是7.6±2.5、9.5±3.0和11.2±3.6,前者明显高于后三者(P<0.05)。结论瘤内注射携带内皮抑素基因的阳离子脂质体,可减少裸鼠体内种植性人肝癌的微血管数目,促进肿瘤细胞凋亡,抑制肿瘤生长。     

肌肉注射内皮抑素基因抑制人大肠癌生长的研究

目的探讨内皮抑素基因治疗大肠癌简便有效的途径.方法构建内皮抑素表达载体,建立BALB/C-nu/n裸鼠大肠癌模型,裸鼠分为3组,每组8只,分别通过肌肉注射生理盐水、对照质粒和表达质粒pST-endo,研究内皮抑素对结肠癌生长的影响.结果荷瘤小鼠经肌肉注射内皮抑素质粒DNA后,肿瘤内细胞凋亡率为24.5±7.3,空白质粒和生理盐水肌肉注射组小鼠肿瘤内细胞凋亡率分别是8.9±2.7和10.2±3.6,前者明显高于后两者;肿瘤内微血管密度(21.7±2.8)却大大少于空白质粒(44.6±11.0)和生理盐水(50.8±13.4)注射组;肿瘤体积在各时间段也明显小于对照的后两组.结论肌肉介导的内皮抑素基因转移治疗大肠癌效果确切.     

硒增强淋巴细胞抑制裸鼠大肠癌生长的研究

目的　研究硒 (Se)作用后淋巴细胞对实验性裸鼠大肠癌的治疗效果及其抗肿瘤作用机制。方法　建立大肠癌细胞株LoVo裸鼠移植瘤的动物模型。将荷瘤裸鼠 72只随机分成对照组、硒组、淋巴细胞组、淋巴细胞 硒组。观察大肠癌移植瘤的生长以及荷瘤动物的肿瘤发生率和生存率 ,采用免疫组织化学法检测肿瘤组织Fas/FasL的表达情况。结果　各组肿瘤体积分别为 (1.970±0 .5 6 6 )mm3 、(1.2 90± 0 .395 )mm3 、(0 .490± 0 .2 0 8)mm3 、(0 .2 70± 0 .139)mm3 ;肿瘤发生率分别为91.6 6 %、75 .0 0 %、5 0 .0 0 %、33.33% ;生存率分别为 16 .6 6 %、33.33%、5 0 .0 0 %、75 .0 0 %。肿瘤组织免疫组织化学结果表明 ,经硒作用后肿瘤细胞Fas和淋巴细胞FasL表达增强。结论　硒有增强淋巴细胞大肠癌细胞移植瘤的作用。     

鼠源性血管抑素对裸鼠种植性肿瘤的抑制作用

目的　探讨鼠源性血管抑素转染入人肝癌细胞SMMC 772 1后对裸鼠种植性肿瘤的影响。　方法　建立鼠源性血管抑素基因的人肝癌SMMC 772 1细胞株 ,实验动物分 3组 :空白对照组种植SMMC 772 1细胞 ,空载体组种植SMMC 772 1/pcDNA3 1(+)细胞 ,血管抑素组种植SMMC 772 1/pcDNA3 1 mAST细胞。比较各组裸鼠肿瘤体积、重量和肿瘤微血管密度 (MVD)。　结果　在肿瘤细胞种植 35d时裸鼠肿瘤体积 :空白对照组 (35 38 1± 6 43 3)mm3 ,空载体组 (312 8 5± 5 46 6 )mm3 ,血管抑素组 (75 5 8± 198 2 )mm3 ;肿瘤重量 :空白对照组 (6 0± 0 7)g,空载体组 (5 9± 0 5 )g ,血管抑素组(2 1± 0 5 )g;肿瘤MVD :空白对照组 5 2 2± 6 6 ,空载体组 49 4± 7 0 ,血管抑素组 2 5 5± 4 1。血管抑素组裸鼠肿瘤体积、重量和MVD显著小于空白对照组和空载体组 (P均 <0 0 1) ,肿瘤的抑制率达78 6 %。　结论　转染血管抑素基因的人肝癌细胞SMMC 772 1在裸鼠体内的致瘤力明显降低 ,肿瘤的体积、重量和微血管密度显著低于对照组 ,表明血管抑素可通过抑制肿瘤血管生成而显著抑制肿瘤生长     

内皮抑素基因对ACHN RCC细胞增殖和凋亡的影响

目的 利用已构建的带有内皮抑素基因真核表达载体质粒导入裸鼠ACHN肾细胞癌(renal cell carcinoma, RCC)细胞中,研究内皮抑素基因对RCC细胞增殖和凋亡的影响.方法 ACHN细胞浓度1×107个/L,经裸鼠右侧背部皮下注射0.2 ml,共注射24只裸鼠.荷瘤裸鼠随机分为3组,每组8只.治疗组:每只裸鼠瘤内3点注射复合物100 μl(内含30 μl梭华-SofastTM和30 μg pSecES质粒);对照组:每只裸鼠瘤内3点注射复合物100 μl(内含30 μl梭华-SofastTM和30 μg pcDNA3.1质粒);空白组:每只裸鼠瘤内3点注射生理盐水100 μl.各组每只裸鼠间隔3 d注射1次,连续注射3次.以增殖细胞核抗原(PCNA)作为细胞增殖状态,按链霉亲和素生物素法(SABC)进行免疫组化染色.细胞凋亡检测用TUNEL法.结果 内皮抑素真核表达质粒能显著抑制裸鼠ACHN RCC肿瘤体积增长,pSecES治疗组平均瘤重明显小于空白组和对照组(P<0.01),与空白组的肿瘤生长抑制率为34.48%,与对照组的肿瘤生长抑制率为40.68%.治疗组肿瘤细胞的凋亡指数(AI)明显高于对照组和空白组(P<0.01).pSecES治疗组肿瘤组织的AI/PI比值明显高于对照组和空白组(F＝189.27,P<0.05).Spearman相关分析表明,肿瘤体积与细胞增殖之间无明显相关性(r =-0.041 2,P>0.05),肿瘤体积与细胞凋亡呈负相关(r =-0.734 6,P<0.01).结论 内皮抑素基因治疗可使裸鼠ACHN RCC肿瘤细胞凋亡增加,肿瘤细胞的数量减少,在总体上表现为肿瘤的生长变慢、体积变小.     

重组人内皮抑素联合应用5氟脲嘧啶对胃癌裸鼠移植瘤的影响

目的探讨重组人内皮抑素(recombinant human endostatin,rhES)与5氟脲嘧啶(5-fluorouracil,5-FU)联合应用对胃癌裸鼠移植瘤生长的抑制作用.方法建立胃癌异位移植BALB/C裸鼠模型,分为4组,每组6只.分别注射生理盐水,腹腔内注射5-FU(10 mg/kg),rhES组瘤周注射rhES(2 mg/kg)同时给予5-FU与rhES,每天1次,连用10 d.计算肿瘤体积、抑瘤率及肿瘤缩小率,检测肿瘤组织血管内皮生长因子(VEGF)、碱性成纤维生长因子(bFGF)、血管内皮生长因子-C(VEGF-C)、Ⅷ因子相关抗原(FⅧAg)、增殖细胞核抗原(PCNA)、bcl-2表达及肿瘤细胞凋亡指数(AI).结果rhES+5-FU组肿瘤体积为(43±2)mm3,5-FU组为(169±45)mm3,rhES组为(95±28)mm3,对照组为(1057±114)mm3(P＜0.01).抑瘤率为99.6%,肿瘤缩小率为98.2%.用药前rhES+5-FU组肿瘤体积为(207±50)mm3,比5-FU组与rhES组下降更迅速(P＜0.01).rhES+5-FU组与5-FU组VEGF、bFGF及VEGF-C表达强度均为0～+;rhES+5-FU组PCNA及bcl-2表达最弱;rhES+5-FU组AI为11.7±1.1,5-FU组为6.2±0.6,rhES组为5.8±0.8,对照组为2.4±0.6(P＜0.01).微血管密度在rhES+5-FU组为8.9±2.5,rhES组为10.0±1.5,均低于5-FU组(27.3±1.7)与对照组(29.9±2.3)(P＜0.01).结论联合应用5-FU及rhES能显著抑制胃癌血管生成,增加肿瘤细胞凋亡,使胃癌裸鼠移植瘤的肿瘤体积明显缩小.     

Angiostatin基因治疗人肝癌裸鼠移植瘤的实验研究

目的:研究Angiostatin基因治疗对人肝癌裸鼠皮下移植瘤的抑制作用及其相关机理。方法:使用人原发性肝癌细胞株SMMC-7721建立人肝癌裸鼠皮下移植瘤动物模型,质粒用脂质体DOTAP介导转染细胞。将荷瘤裸鼠随机分为两组,分别注射质粒PcDNA3、Angiostatin/PcDNA3,观察两组动物的肿瘤生长曲线,检测肿瘤的Angiostatin、VEGF、HIF-1α表达和微血管密度(MVD),利用TUNEL染色法行原位细胞凋亡分析。结果:Angiostatin基因治疗在早期具有抑制肿瘤生长的作用,大约1周后肿瘤以更快的速度生长并迅速赶上空质粒对照组肿瘤;Angiostatin基因治疗组的肿瘤组织中有An-giostatin的局部高表达,MVD(24.8±2.8)低于空质粒对照组(30.2±4.1)(P〈0.05)。肿瘤组织中HIF-1α蛋白局部高表达,VEGF表达高于空质粒对照组,细胞凋亡指数(2.87±0.48)高于空质粒对照组(1.55±0.43)(P〈0.01)。结论:Angiostatin基因治疗对人肝癌裸鼠皮下移植瘤的生长具有一定的抑制作用,肿瘤对Angiostatin基因治疗可以产生耐受性。     

经肝动脉或瘤体注射单纯疱疹病毒-胸苷激酶基因治疗兔肝癌

目的　观察瘤体内直接注射或经肝动脉注射载有单纯疱疹病毒胸苷激酶 (HSV TK)基因的EB病毒表达质粒 pDR2 /TK、丙氧鸟苷 (GCV )对原位兔肝癌的治疗效果。 方法　制作兔原位肝癌模型 (VX2 ) ,瘤体注射或经肝动脉注射质粒 pDR2 /TK ,腹腔注射GCV连续 10d。RT PCR检测肝癌HSV TK表达 ;螺旋CT监测肝癌大小 ,并观察兔存活时间。结果TK基因导入 10d后 ,直接注射组TK在肝癌组织强表达 ,癌旁组织弱表达 ,正常肝组织不表达 ;肝动脉注射组TK基因在肝癌表达稍强于癌旁及正常肝组织。直接注射组肿瘤大小 ( 3 .5 5± 0 .3 9)cm ,与经肝动脉注射+肝动脉结扎组肿瘤大小 ( 3 .70± 0 .3 7)cm无明显差别 (P >0 .0 5 ) ,但均明显小于对照组。瘤体直接注射TK基因 +GCV治疗组动物平均存活时间 ( 5 9.8± 3 .3 )d、肝动脉注射组 +肝动脉结扎组( 5 4.8± 4.5 )d明显长于各对照组 (P均 <0 .0 1)。结论　对实验性兔肝癌 ,瘤体内直接注射或经肝动脉注射导入治疗基因后 ,HSV TK/GCV系统具有较好的治疗效果。     

热休克蛋白-多肽复合物/树突状细胞疫苗的研究

目的　探讨从肺癌组织中提取的热休克蛋白GP96 多肽复合物 (GP96)负载树突状细胞 (DC)疫苗在小鼠体内的抗肿瘤作用。方法　自小鼠肺腺癌LA795肿瘤组织中提取GP96,自615小鼠外周血中提取单个核细胞体外培养DC ,共孵育制备疫苗 ,分别以GP96(5 μg/只 )、DC(5×10 5个 /只 )和GP96/DC(DC5× 10 5个 /只 ,培养时加入 5 μgGP96)免疫小鼠后接种肿瘤 ,与未免疫组比较成瘤率、肿瘤体积及生存时间。同时以联合免疫缺陷小鼠 (SCID )进行类似实验 ,肿瘤组织为人肺腺癌PAa ,DC来源于人外周血 ,分组剂量同上。结果　 615组小鼠成瘤率分别为 10 0 %、10 0 %、10 0 %和 75 % ,肿瘤体积为 (6.46± 1.47)cm3 ,(0 .70± 0 .62 )cm3 ,(0 .64± 0 .49)cm3 和(0 .3 2± 0 .3 0 )cm3 ,生存时间为 5 2、5 1.5、5 8.5和 77d ,SCID组小鼠成瘤率分别为 10 0 %、10 0 %、10 0 %和 87.5 % ,肿瘤体积为 (0 .75± 0 .3 0 )cm3 ,(0 .17± 0 .0 6)cm3 ,(0 .15± 0 .0 8)cm3 和 (0 .0 8±0 .0 3 )cm3 ,生存时间为 3 7、5 2、5 2 .5和 77d。结论　GP96/DC疫苗有更明显的抑制肿瘤生长的作用。     

CMTM5对人前列腺癌裸鼠移植瘤的抑制作用

目的:探讨CMTM5(CKLF-like MARVEL transmembrance domain containing)对人前列腺癌裸鼠移植瘤的抑制作用,并初步探索其作用机制。方法:13只雄性裸鼠连续腹腔注射环磷酰胺2.5 mg/(d.只),建立裸鼠皮下前列腺移植瘤模型,3周后11只裸鼠种植部位可见肿瘤,随机将其分成两组:实验组(6只),对照组(5只)。实验组肿瘤局部注射CMTM5腺病毒,对照组不作处理。每日监测裸鼠体重和肿瘤大小,2周后处死。取出完整肿瘤组织,利用免疫组化方法检测过表达CMTM5对裸鼠前列腺移植瘤组织中血管内皮生长因子(VEGF)及核转录因子κB(NF-κB)蛋白表达的影响。结果:CMTM5组肿瘤体积为(573.39±175.24)mm3明显小于对照组(1482.50±327.86)mm3,P=0.03。CMTM5组肿瘤重量为(0.55±0.11)g明显小于对照组(1.31±0.29)g,P=0.027。免疫组化法检测结果显示,与对照组比较,CMTM5组VEGF和NF-κB蛋白的表达明显降低。结论:CMTM5抑制前列腺癌的生长,其作用机制可能通过下调与肿瘤细胞增殖密切相关的血管内皮生长因子VEGF和核转录因子NF-κB的表达相关。     

A human monoclonal antibody reactive with human prostate

A human immunoglobulin M monoclonal antibody secreting hybridoma, termed MHG7, has been isolated and characterized for its reactivity against human prostate cells. Lymphocytes isolated from a regional draining lymph node of a patient with prostate carcinoma were fused with murine P3-NS1-Ag4-1 myeloma cells. Supernatants from the generated mouse-human somatic cell hybrids were first screened for human immunoglobulin production by an enzyme immunoassay. The identified human immunoglobulin-secreting hybridomas were expanded for further analysis and their supernatants screened by enzyme immunoassay against a panel of prostate cell lines. The human immunoglobulin M monoclonal antibody MHG7, in addition to reacting with prostate cell lines, also reacted with prostate carcinoma cells and benign prostatic hypertrophy cells on both frozen and paraffin embedded tissue sections. These data suggest that regional draining lymph nodes of prostate carcinoma patients can be used as a source of human lymphocytes for generating human immunoglobulin-secreting hybridomas reactive with human prostate cells.     

Expression of toxin-related human mono-ADP-ribosyltransferase 3 in human testes

目的:研究单腺苷二磷酸-核糖基转移酶3(ART3)的 mRNA 在人类睾丸中是否表达其相应的蛋白,如果有表达是否细胞特异性表达。方法:用逆转录聚合酶链反应(RT-PCR)确定人类睾丸和精子中 ART3的mRNA 水平。用磷脂酶 C 处理转染了 ART3的 HEK-293-T 细胞,并通过它检测 ART3的糖基化磷酸肌醇链。用荧光激活细胞分类(FACS)分析和免疫组织学方法分别检测 ART3蛋白在成熟精子和睾丸中的表达。结果:ART3蛋白在睾丸和精母细胞中有表达,而在精原细胞、精子细胞和精子中未检测到,FACS 分析进一步确认精子中无 ART3蛋白。在精原细胞瘤和睾丸间细胞中也未检测到 ART3蛋白。结论:本研究首次发现ART3蛋白在睾丸中表达,尤其是在精母细胞中,这表明 ART3执行一个特定的功能,此功能只在精子发生的某个特殊阶段发挥作用。     

Modulation of human chondrocyte metabolism by recombinant human interferon

OBJECTIVES: Interferon gamma (IFN gamma) is found to be elevated in the synovial fluid of patients with rheumatoid arthritis and osteoarthritis, suggesting its implication in joint disease pathogenesis. In this study, we investigated the effects of IFN gamma on the production of cytokines (IL-6, IL-8, IL-10), prostaglandin E(2)(PGE(2)), proteoglycans (PG), nitric oxide (NO), interleukin-1 receptor antagonist (IL-1ra) and stromelysin by non-stimulated and IL-1 beta-treated human chondrocytes. The role played by NO in the responses of chondrocytes to IFN gamma was also examined by incubation of chondrocytes with N(G)-monomethyl-L-arginine (L-NMMA), a competitive inhibitor of NO synthase. METHODS: Enzymatically isolated human chondrocytes were cultured for 48 h in the absence or presence of IL-1 beta, IFN gamma or N(G)-monomethyl-L-arginine (L-NMMA) added solely or in combination. The productions of IL-6, IL-8, IL-10, IL-1ra and stromelysin were measured by enzyme amplified sensitivity immunoassays (EASIA). PG and PGE(2)were quantified by specific radioimmunoassays (RIA). Nitrite concentrations in the culture supernatants were determined by a spectrophotometric method based upon the Griess reaction. RESULTS: As expected, IL-1 beta highly stimulated NO, IL-6, IL-8, IL-10, IL-1ra, PGE(2)and stromelysin synthesis, but dramatically decreased PG production. NO, IL-6, IL-1ra and PGE(2)production by non-stimulated chondrocytes was dose-dependently increased by IFN gamma while PG production was inhibited. In the absence of IL-1 beta, IL-10 was undetectable in the culture supernatants. At the doses of 10 and 100 U/ml, IFN gamma markedly inhibited the constitutive and IL-1 beta-stimulated IL-8, IL-10 and stromelysin productions. Interestingly, IFN gamma synergized with IL-1 beta to increase NO, IL-6, IL-1ra and to depress PG production. As previously reported, the inhibition of NO synthesis by the competitive inhibitor L-NMMA led to enhancement of IL-6, IL-8 and PGE(2)production by IL-1 beta treated chondrocytes, but did not significantly modify IL-10, PG and MMP-3 productions. Inhibition of NO synthase significantly inhibited the stimulating effect of IFN gamma on IL-6 and IL-1ra but did not affect the inhibitory effect of IFN gamma on IL-8, PG or stromelysin production. CONCLUSIONS: These findings suggest that IFN gamma and IL-1 synergistically stimulate the production of IL-6, IL-1ra, NO and PGE(2)and inhibit PG synthesis. By contrast, IL-1 beta and IFN gamma have opposite effects on IL-8, IL-10 and stromelysin productions. These effects are not reversed by L-NMMA, suggesting that NO is not the principal mediator involved in responses of chondrocytes to IFN gamma.     

Endothelialization of human collagen surfaces with human adult endothelial cells

Artificial vascular grafts are currently used to restore blood flow to ischemic tissue. Although the long-term patency of large diameter grafts is relatively acceptable, small diameter (less than 4 mm) grafts exhibit poor long-term patency rates. One technique to create a nonthrombogenic surface on artificial prostheses has been to seed with endothelial cells derived from autologous vessels. We have examined the interaction of human adult endothelial cells with the natural collagen surfaces presented by human amnion. Scanning electron microscopic evaluation revealed that human adult endothelial cells adhered rapidly to both the basement surface (collagen types IV and V) and interstitial surface (collagen types I and III) of amnion. However, the adherence of cells was significantly greater on the basement membrane surface. In addition, human adult endothelial cells rapidly formed close cell-to-cell interactions on basement membrane as compared with cells seeded onto the interstitial surface. These results suggest that seeding of endothelial cells onto artificial surfaces will be facilitated if the surface simulates the natural basement membrane to which endothelial cells natively adhere.     

Adult human enamel

A study was conducted to determine the effect of sample preparation (grinding method) upon breadth of the diffraction profile of enamel. Collecting enamel by grinding with various cuttin tools in the low-speed dental handpiece caused broadening of all peaks (002, 211, 300 and 202) examined, compared to ball, ground, counter-part enamel. Line broadening was not observed when a single crystal of mineral hydroxyapatite was ground with a very fine diamond. In general, broadening was less pronounced with the high-speed air turbine technique. The amount of broadening caused by dental burs depended upon one or more of the following factors: coarseness of cutting instrument, grinding speed, grinding direction, and the presence or absence of water. Prolonged ball grinding of enamel also caused broadening; under identical conditions, however, annealed bone remained undamaged. These findings indicate that enamel is more sensitive to grinding damage than the mineral hydroxyapatite crystal or annealed bone. The actual cause of line broadening may be either strain due to lattice distortions or a reduction in size of individual crystallites.COSTEP Summer 1966     

Potent oncolytic activity of human enteroviruses against human prostate cancer

BACKGROUND: Oncolytic virotherapy offers a unique treatment modality for prostate cancer, especially stages that are resistant to current therapies, with the additional benefit of preferentially targeting tumor cells amongst an environment of healthy tissue. Herein, the low pathogenic enteroviruses; Coxsackievirus A21 (CVA21), as well as a bio-selected variant of Coxsackievirus A21 (CVA21-DAFv) and Echovirus 1 (EV1) are evaluated as novel oncolytic agents against human prostate cancer. METHODS: The surface expression of viral receptors required for enterovirus cell attachment/entry, including intercellular adhesion molecule-1 (ICAM-1), decay-accelerating factor (DAF) and integrin alpha(2)beta(1) on a number of human prostate cancer lines was assessed by flow cytometry. Susceptibility to viral oncolysis was determined via in vitro cell lysis assays performed on cell monolayers cultured in micro titer plates. The in vivo oncolytic efficacy of the enteroviruses was assessed using xenograft models in immune compromised SCID-mice following systemic challenge. RESULTS: The majority of prostate cancer lines tested expressed surface ICAM-1 and/or DAF, or alpha(2)beta(1), facilitating significant degrees of oncolysis following in vitro viral challenge. Systemic delivery of each of the three viruses induced reduction of xenograft tumor burdens in vivo, and a therapeutic dose-response was demonstrated for escalating doses of EV1 in the LNCaP animal model. CONCLUSION: Enteroviruses CVA21, CVA21-DAFv, and EV1 are potentially potent oncolytic agents against human prostate cancer.     

The human wedge

The important part of resuscitation in late pregnancy is the relief of aortocaval compression. A manoeuvre to relieve aortocaval compression (the human wedge) is described and evaluated. Eighteen qualified midwives performed basic life support in the supine and wedged position employing the human wedge. Performance was assessed using the Laerdal Resusci Anne Skillmeter. There was no difference (p = 0.4761) in performance of mouth-to-mouth expired air ventilation between the two positions. External cardiac compressions were performed significantly better (p = 0.0005) in the wedged position than in the supine position. The human wedge may provide an alternative to other methods of relieving aortocaval compression.     

培养的人睾丸组织对人绒毛膜促性腺激素的反应

用猝死的正常成年男子睾丸组织，加入含有１０％胎牛血清的ＭＥＭ培养液，培养１４天。观察睾丸组织在培养期间对人绒毛膜促性腺激素（ｈＣＧ）０～５０ＩＵ／ｍｌ的反应，氧耗量测定及形态学观察。结果表明体外培养的人睾丸组织有３天适应期，第４天逐渐恢复分泌功能。在培养前期（０天）、中期（７天）、后期（１４天）对相同剂量ｈＣＧ刺激的睾酮分泌反应及氧耗量无显著差异（Ｐ＞０．０５）。光镜和电镜下可见睾丸组织结构完整。第１４天生精细胞有退行性变，少数赖迪细胞空泡样变     

Adult human enamel

A study in the electron microscope was carried out to determine if the broadening of X-ray diffraction patterns was related to crystal fragmentation or strain resulting from the preparative technique. All enamel samples, collected either by grinding with high- or low-speed diamond stones or by carbide burs, contained large amounts of finely-divided enamel, a relatively large number of scattered individual crystals and relatively few particles (usually <5 in size), containing varying numbers of intact crystals. Ball-ground control samples contained aggregates of unbroken crystallites 5–10 in size. Prolonged ball grinding produced a significant amount of finely-divided material (<0.025 ), the amount increasing with increased grinding. Particle sizes of material ground from a large single crystal of synthetic hydroxyapatite with a low-speed diamond stone ranged from <0.025 to >5 , the larger particles predominating. Annealing bone crystallites increased their size appreciably but they remained undamaged despite prolonged grinding in the ball mill. There was no evidence to suggest a plane of preferred cleavage in enamel; the composite nature and crystal morphology may be responsible, therefore, for the severe fragmentation observed. Crystallite fragmentation is probably responsible for the line-broadening observed in the X-ray diffraction pattern, although strain may also be a contributing factor.

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Zusammenfassung Es wurde am Elektronenmikroskop untersucht, ob die Verbreiterung der Röntgendiffraktionsbanden, welche nach verschiedenen Aufbereitungstechniken beobachtet werden konnte, auf eine Kristallzertrümmerung oder auf Druck zurückzuführen ist. Alle Schmelzproben, die durch Zerreiben mit hoch- oder niedrigtourigen Diamantsteinen oder mit Carbidbohrern gewonnen wurden, enthielten große Mengen von feinabgespaltenem Schmelz, eine relativ große Anzahl von verstreuten einzelnen Kristallen und relativ wenig Partikel (gewöhnlich <5 ), die aus einer variablen Anzahl von intakten Kristallen bestanden. Mit dem Kugelbohrer gewonnene Kontrollproben enthielten Aggregate von intakten Kriställchen in der Größe von 5–10 . Längeres Zerreiben mit dem Kugelbohrer ergab signifikante Mengen von feinabgespaltenem Material (<250 Å), das sich mit zunehmendem Zerreiben noch vermehrte. Wurde ein einzelner großer synthetischer Hydroxyapatitkristall mit einem niedrigtourigen Diamantstein zerrieben, so variierte die Größe der Partikel zwischen <250 Å und >5 , wobei die größeren Partikel vorherrschten. Knochenkriställchen erfuhren beim Ausglühen eine merkliche Vergrößerung, blieben jedoch unbeschädigt nach verlängertem Zerreiben in der Kugelmühle. Es konnte nicht bewiesen werden, daß im Schmelz die Abspaltung nach bevorzugten Flächen vorgeht; die komplexe Natur und die Kristallmorphologie können deshalb für die beobachtete starke Zertrümmerung verantwortlich gemacht werden. Die Bandenverbreiterung, die bei der Röntgendiffraktion beobachtet werden konnte, ist wahrscheinlich auf die Zertrümmerung der Kristalle zurückzuführen, obschon auch Druck als Faktor eine Rolle spielen kann.

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Résumé Une étude de microscopie électronique est réalisée pour déterminer si l'élargissement des raies des diagrammes de diffraction aux rayons X, observée après divers procédés de préparation, est liée à la fragmentation des cristaux ou à l'espèce cristalline considérée. Les échantillons d'émail, obtenus par meulage à l'aide de diamants ou de fraises de carbones, tournant à grandes ou à petites vitesses, contiennent de grandes quantités d'émail finement pulvérisé, des quantités relativement grandes de cristaux individuels disséminés et relativement peu de particules (habituellement inférieures à 5 microns), contenant un nombre variable de cristaux intacts. Des échantillons témoins, obtenus par meulage à l'aide de billes, contiennent des cristaux intacts de 5–10 microns. Un meulage prolongé à l'aide de billes donne des quantités importantes de produits fins (inférieurs à 0.025 microns), qui augmentent avec un meulage plus prolongé. Les tailles des particules d'un monocristal d'hydroxyle-apatite synthétique, préparé à l'aide d'une meulette diamantée, tournant à faible vitesse, variant de <0.025 microns à >5 microns: les particules plus larges prédominent. Le fait de chauffer les cristaux d'os augmente nettement leur taille: par contre ils ne se modifient pas après meulage à l'aide de billes. Un plan de clivage préférentiel n'a pu être mis en évidence dans l'émail. La nature hétérogène et la morphologie cristalline peuvent, par conséquent, être responsables de la fragmentation élevée, qui a pu être constatée. Cette fragmentation cristalline est probablement responsable de l'élargissement des raies de diffraction aux rayons X, bien que l'espèce cristalline considérée puisse également être en cause.