南方食管癌高低发区人群尿总N-亚硝基化合物与N-亚硝基氨基酸关系研究

为了解尿总亚硝基化合物指标在南方食管癌亚硝胺病因研究中的作用 ,探讨该指标与传统亚硝基氨基酸指标的关系。在南方食管高发区南澳县和低发区陆丰县各随机选择 1 2 0名 35～ 64岁健康男性 ,收集1 2小时尿液测定总N 亚硝基化合物 (TNOC)水平和 4种N 亚硝基氨基酸 (NAAs)含量。结果表明 ,尿中总N 亚硝基化合物含量与南方食管癌死亡率呈正相关关系 (rs=0 2 5 ,P <0 0 5)。食管癌高发区人群尿中总N 亚硝基化合物仅有 7 5 %来自 4种N 亚硝基氨基酸。低发区人群尿总N 亚硝基化合物中 4种N 亚硝基氨基酸占了 57%。南方食管癌高发区人群尿样中亚硝胺成份较低发区复杂。尿总亚硝基化合物指标是评价人体亚硝胺接触水平的良好指标 ,可用于食管癌亚硝胺病因研究。当尿中亚硝胺种类较少时 ,总亚硝基化合物指标与亚硝基氨基酸指标才有相关性。本研究结果支持南方食管癌的亚硝胺病因假说     

南方食管癌高、低发区人群总N-亚硝基化合物接触水平

目的　评价南方食管癌高发区和低发区人群总N 亚硝基化合物 (TNOC)的接触水平。方法　在食管癌高发区南澳县和低发区陆丰县各随机选择 12 0名 35～ 6 4岁男性 ,采用双份饭法收集2 4h膳食和 12h尿液 ,测定TNOC、非挥发性亚硝胺和挥发性亚硝胺。结果　高发区膳食TNOC检出率(95 % )、膳食TNOC日摄入量 [(4 2 5± 0 84 ) μmol/d]和尿 12h排出量 [(1 76± 0 2 3)ng/ 12h]、膳食挥发性亚硝胺日摄入量 [(2 6 6± 31 2 ) μg/d]均高于低发区。食管癌死亡率分别与膳食TNOC日摄入量和尿TNOC排泄量呈等级正相关关系。尿非挥发性亚硝胺排泄量两地无差异。结论　南方食管癌高发区人群TNOC的接触水平明显高于低发区人群     

食品卫生

050286　南方食管癌高、低发区人群总N亚硝基化合物接触水平/林　昆…∥中华预防医学杂志2002,36(6)386～389评价南方食管癌高发区和低发区人群总N亚硝基化合物(TNOC)的接触水平。在食管癌高发区南澳县和低发区陆丰县各随机选择120名35～64岁男性,采用双份饭法收集24h膳食和12h     

大蒜阻断人体内N-亚硝基脯氨酸的合成

本文采用Ohshima以GC-TEA定量测定尿中N-亚硝基脯氨酸排出量的方法,以9名健康志愿者为对象,研究大蒜阻断人体内N-亚硝基脯氨酸的合成。受试者食生大蒜5g能完全阻断300mg硝酸钠与500mgL-脯氨酸在人体内合成N-亚硝基脯氨酸,平均阻断率为114.68％,为人群食大蒜预防内源性N-亚硝基化合物的合成及由此造成的致癌性危害提供科学依据。     

中华猕猴桃汁阻断胃癌高发区人群的内源性N-亚硝基化合物合成

本文以空腹胃液中挥发性亚硝胺(VNA)和24小时尿N-亚硝基脯氨酸(NPRO)排出量为指标,观察中华猕猴桃汁(简称桃汁)阻断胃癌高发区人群内源性N-亚硝基化合物(NOC)合成的阻断作用。受试者服用30ml桃汁后,空腹胃液中VNA总量由平均2.08±1.06μg/L显著下降至0.42±0.43μg/L(P<0.01),阻断率为79.8％。在NPRO试验中,受试验者摄入300mg脯氨酸后,尿NPRO排出量由本底的3.3±1.2μg/d显著升高至9.4±4.7μg/d(P<0.001)。与脯氨酸同时服用30ml桃汁后,NPRO排出量显著降低至本底水平(2.9±1.9μg/d,P<0.001)。上述阻断作用在胃粘膜病变程度不同的三组人群间未见显著性差别(P>0.1)。本研究证实,中华猕猴桃汁能有效地阻断胃癌高危人群内源性NOC合成。     

淮安市居民早期食管癌危险因素的病例对照研究

目的探讨淮安市居民食管癌发病危险因素,为食管癌早诊早治和综合防治提供科学依据。方法在淮安市洪泽、金湖两县区采用1∶1病例对照研究方法,对食管癌病例和正常对照进行调查,采用条件logistic回归对结果进行分析。结果单因素分析显示,经常食用腌晒食品,有癌症家族史,患胃十二指肠溃疡、食管炎或胃肠炎5个因素与食管癌的发病相关(P值均0.05)。多因素logistic回归显示,经常食用腌晒食品(OR=1.625,95%CI:1.037~2.546)、有癌症家族史(OR=4.459,95%CI:2.672~7.442)、患胃十二指肠溃疡(OR=3.080,95%CI:1.454~6.524)或食管炎(OR=1.842,95%CI:1.035~3.277)是食管癌发病的危险因素。结论经常食用腌晒食品,有癌症家族史,患胃十二指肠溃疡或食管炎是食管癌发生的危险因素,在积极开展食管癌防治宣传基础上,应该继续推进食管癌早诊早治项目,有效控制食管癌的发生和发展。     

淮安市沿淮河居民食管癌及癌前病变影响因素的多元有序logistic回归分析

目的探讨淮安市沿淮河居民食管癌及癌前病变发病的危险因素,为食管癌的防治提供依据。方法采用整群抽样方法抽取洪泽、金湖两地食管癌高发区居民作为研究对象,进行危险因素问卷调查,对问卷调查评价出的高危人群进行碘染色内镜筛查,并取活检组织进行病理诊断,依据病理诊断标准分为不同病变等级,并采用多元有序logistic回归对食管癌及癌前病变影响因素进行分析。结果该研究共收集参加碘染色内镜筛查居民4 001例,对照组(内镜检查正常)3 042例,轻中度异常增生组746例,重度异常增生及以上组213例。单因素分析结果显示,食管癌及癌前病变的发生与学历、饮用水来源、吸烟、饮酒、水果食用频率、肉类食用频率、腌制食品食用频率、油炸食品食用频率、性格类型、胃十二指肠溃疡、食管炎、胃肠炎疾病史和肿瘤家族史有关,有统计学意义(P0.05,P0.01)。多因素有序logistic回归分析结果表明,吸烟(OR=1.22,95%CI:1.02~1.46)、饮酒(OR=1.38,95%CI:1.14~1.68)、经常吃腌制食品(OR=1.76,95%CI:1.47~2.13)、经常吃油炸食品(OR=2.10,95%CI:1.41~3.15)、胃十二指肠溃疡疾病史(OR=1.57,95%CI:1.28~1.93)、食管炎疾病史(OR=1.44,95%CI:1.07~1.92)、胃肠炎疾病史(OR=1.46,95%CI:1.24~1.73)、肿瘤家族史(OR=2.70,95%CI:2.32~3.15)是食管癌及癌前病变发生的独立危险因素。结论淮安市沿淮河居民食管癌及癌前病变发生受遗传因素、膳食结构、生活方式及多因素共同影响,建议采取综合措施,积极改变不良的生活方式,对于高危人群,应该积极参加筛查,做到早诊早治。     

社区老年人2型糖尿病膳食危险因素分析

目的分析社区老年人2型糖尿病(T2DM)的膳食危险因素,为T2DM的膳食防治提供科学依据。方法在体检人群中随机选取T2DM患者与健康对照者各426例进行病例-对照研究,体检者进行体格检查和实验室检查,并进行膳食问卷调查。比较两组间各变量差异,应用非条件logistic回归法分析T2DM膳食危险因素。结果病例组体质指数、收缩压、舒张压、空腹血糖、血清甘油三酯均高于对照组,差异均有统计学意义(P0.01);每日摄入能量[(1 941.96±843.14)kcal]、蛋白质[(84.36±51.37)g]、维生素A[(1 155.91±332.52)μg RE]、铁[(40.43±28.91)mg]、锌[(12.77±10.86)mg]、硒[(64.12±35.87)μg]均高于对照组[每日摄入能量(1 806.86±581.48)kcal、蛋白质(76.67±26.02)g、维生素A(745.53±121.52)μg RE、铁(34.23±11.63)mg、锌(11.11±7.97)mg、硒(55.73±21.54)μg],差异均有统计学意义(P0.05,P0.01);膳食纤维[(21.76±7.38)g]、硫胺素[(1.66±0.14)mg]、钙[(870.84±226.21)mg]均低于对照组[膳食纤维(24.07±10.16)g、硫胺素(2.23±0.51)mg、钙(961.67±297.31)mg],差异均有统计学意义(P0.05,P0.01);碳水化合物供能比(63.67%±6.66%)低于对照组(63.92%±6.65%),蛋白质供能比(15.32%±2.59%)高于对照组(15.17%±2.49%),差异均有统计学意义(P0.01,P0.05);多因素非条件logistic回归分析显示,蛋白质(OR=1.015,95%CI:1.003~1.025)、铁(OR=1.003,95%CI:1.001~1.010)和维生素A(OR=1.004,95%CI:1.001~1.012)是T2DM的膳食危险因素,膳食纤维(OR=0.896,95%CI:0.884~0.918)、钙(OR=0.988,95%CI:0.972~0.998)和硫胺素(OR=0.406,95%CI:0.395~0.429)是T2DM的膳食保护因素。结论适当控制能量、蛋白质的摄入,适量增加蔬菜、水果等含食膳食纤维多的食物以及富含硫胺素的食物可以预防和减少T2DM的发生。     

茶叶对人体内源性亚硝化的影响

本文研究了茶叶对人体内N-亚硝基化合物形成的影响。实验结果表明,日饮一杯茶(3～5g绿茶或5g红茶)可阻断人体摄入300mg硝酸盐后N-亚(?)基脯氨酸的内源性合成,这提示茶叶具有降低人体对强致癌物N-亚硝基化合物接触的作用。     

地铁工作人员抑郁现状及影响因素分析

目的对W市地铁2号线工作人员的抑郁症状现状及其影响因素进行分析,为预防和控制地铁职业人群心理问题提供科学依据。方法使用横断面流行病学调查方法对研究对象社会人口学特征、工作环境特征、个体行为方式进行调查,利用抑郁自评量表(SDS量表)对抑郁症状进行评价。多因素logistic回归分析抑郁症状的相关影响因素。结果本次调查地铁工作人员1 152例,抑郁症状检出率为66. 4%。多因素logistic回归分析结果显示,影响地铁工作人员抑郁的保护因素包括个人月均收入高(OR=0. 676,95%CI:0. 478~0. 956)、运动(OR=0. 699,95%CI:0. 515~0. 948)、睡眠时间适中(OR=0. 731,95%CI:0. 568~0. 941)和睡眠状况好(OR=0. 539,95%CI:0. 408~0. 713);危险因素包括女性(OR=1. 538,95%CI:1. 127~2. 099)、年龄增加(OR=1. 020,95%CI:1. 000~1. 040)、上夜班(OR=1. 757,95%CI:1. 238~2. 492)。结论地铁工作人员抑郁症状检出率较高,应加强地铁工作人员心理健康的研究,及时采取干预措施,保护其身心健康。     

市售腊肠中总亚硝基化合物检测

目的建立腊肠总亚硝基化合物(TNOC)测定方法,调查腊肠中TNOC污染情况。方法在以往液体标本测定方法的基础上建立腊肠TNOC的化学裂解-热能分析仪测定方法,该法具有区分热和酸不稳定物质的优点。随机采集市售腊肠32份,采用化学裂解-热能分析仪法测定腊肠中总亚硝基化合物含量。结果研究发现,AG1-X8阴离子树脂可以有效去除样品中硝酸盐的干扰,又不影响亚硝基化合物的测定;0.2%HCl/HAc既能很好裂解NaNO2,又不会使不稳定的亚硝酰胺大量分解;样品加标平均回收率为86%(83%~89%);TNOC检出限为6.6μg(N-NO)/kg,相对标准差为5.9%。32份腊肠样品中TNOC检出率为93.8%;平均含量为49.09μg/kg(95%CI39.15~126.35μg/kg)。结论该方法具有准确性和可重复性。腊肠中TNOC污染较普遍,应当加强这方面的食品卫生监督。     

我国南方食管癌高发区膳食亚硝胺水平及其相关因素研究

广东省南澳县是我国南方食管癌高发区。环境中可疑病因——亚硝胺及其前体物正日益受到人们的关注。为此，我们从当地居民所吃膳食中采集５５份样品，用ＧＣ－ＴＥＡ测定挥发性亚硝胺及其前体物。样品中检出二甲基亚硝胺（ＮＤ－ＭＡ）、二乙基亚硝胺（ＮＤＥＡ）、亚硝基吡咯烷（ＮＰＹＲ）、亚硝基哌啶（ＮＰＩＰ）及甲基苄基亚硝胺（ＮＭＢｚＡ）。它们的平均水平（中位数）为３１２．０μｇ／ｋｇ，人均日摄入总量为２８６．５μｇ。通过逐步回归及曲线拟合法研究亚硝胺、前体物及主要食物类型间的相关关系。结果表明：该地区膳食中挥发性亚硝胺含量较高。     

Occupation and risk of esophageal and gastric cardia adenocarcinoma

BACKGROUND: Adenocarcinomas of the esophagus and gastric cardia have risen dramatically in incidence over the past few decades, however, little research has been conducted on the occupational risk factors for these cancers. METHODS: In this population-based case-control study, lifetime job histories were compared between cases of esophageal adenocarcinoma (n = 283), gastric cardia adenocarcinoma (n = 259), and population controls (n = 689). Odds ratios (OR) and 95% confidence intervals (CI) for ever employment and by duration in various occupational and industrial categories were calculated using unconditional logistic regression. RESULTS: The risk of esophageal adenocarcinoma was elevated for persons ever employed in administrative support (OR = 1.5; 95%CI = 1.0-2.1); financial, insurance, and real estate (OR = 1.6; 95%CI = 1.0-2.4); and health services (OR = 2.2; 95%CI = 1.2-3.9). The risk of gastric cardia adenocarcinoma was increased among transportation workers (OR = 1.7; 95%CI = 1.1-2.6), as well as among carpenters (OR = 1.8; 95%CI = 0.9-3.9) and workers in the furniture manufacturing industry (OR = 2.4; 95%CI = 0.9-6.3). However, we observed few duration-response relations between length of employment in any category and cancer risk. CONCLUSIONS: This study revealed associations of esophageal adenocarcinoma with employment in administrative support, health services, and a category of financial, insurance, and real estate industries, and of gastric cardia adenocarcinoma with transportation and certain woodworking occupations. Some of these findings may be due to the play of chance associated with the multiple comparisons made in this study. Our results suggest that, overall, workplace exposures play a minor role in the etiology and upward trend of esophageal and gastric cardia adenocarcinomas.     

Dietary Nitrates, Nitrites, and N-Nitroso Compounds and Cancer Risk: A Review of the Epidemiologic Evidence

Experimental animal studies have shown N-nitroso compounds (NOC) to be potent carcinogens. Epidemiologic evidence of the carcinogenic potential of dietary NOC and precursor nitrates and nitrites in humans remains inconclusive with regard to the risk of stomach, brain, esophageal, and nasopharyngeal cancers. Inadequate available data could obscure a small to moderate effect of NOC.     

West Coast study of childhood brain tumours and maternal use of hair-colouring products

The immature nervous system of the fetus is characterised by rapid cell growth and division and is particularly vulnerable to carcinogens and mutagens. Several epidemiological studies have reported an increased risk for childhood brain tumours (CBT) associated with exposure to N-nitroso compounds (NOC). Hair-colouring products (hair "dyes") that contain NOC-related aromatic amines have shown mutagenicity in vitro and carcinogenic properties in vivo. The potential public health impact of the relationship between hair dye use and carcinogenesis has prompted epidemiological research, given that a large proportion of American women have used hair dyes. A large population-based case-control study was conducted on the west coast of the USA to investigate risk factors for CBT including exposure to NOC. Eligible CBT patients (<20 years of age and diagnosed between 1984 and 1991) were identified from cancer registries in Los Angeles County, the San Francisco Bay Area in California and the Seattle area in Washington state. A total of 540 biological mothers of these children were interviewed, and 801 control subjects who were frequency matched to the CBT patients on birth year and sex were obtained using random digit dialling. Mothers were asked details about personal use of hair dyes during the index pregnancy including frequency of use, trimester of use and type of dye used. Results from age- and sex-adjusted unconditional logistic regression analyses showed no association between risk for CBT and use of hair dyes 1 month before and/or during pregnancy nor during specific trimesters. A nearly twofold increased risk for CBT was associated with single-interval use during the 1 month before pregnancy, but the confidence interval (CI) was imprecise and the estimate was not different from unity (OR = 1.9, 95% CI [0.5, 7.0]). Exclusive use of permanent dye, temporary dye or hair darkeners was not associated with risk for CBT. A twofold increased risk (OR = 2.0, 95% CI [0.83, 4.7]) was observed with exclusive use of semi-permanent dye during the month before or during pregnancy. Exclusive use of semi-permanent dye during the month before pregnancy and/or first trimester also was associated with an elevated risk for CBT, again not different from unity and with an imprecise CI (OR = 2.5, 95% CI = [0.58, 10.3]). There was no evidence of an association between risk for CBT by histological subtypes and use of hair dyes during the index pregnancy or the month before conception. Together with results from previous studies, these results provide no consistent evidence of an association between risk for CBT and use of hair dyes during pregnancy.     

乙醇和乙醛脱氢酶基因多态与食道癌易感性

目的 研究乙醇脱氢酶2(ADH2)和乙醛脱氧酶2(ALDH2)基因多态与食道癌易感性.方法 对江苏省泰兴市221例食道癌新发病例和191名对照的饮酒习惯等因素进行调查,采用PCR和变性高效液相色谱法(DHPLC)检测ADH2和ALDH2基因型.结果 (1)与携带ALDH2 G/G基因型者相比,携带ALDH2A/A(OR=5.69,95%CI:2.51～12.18)和ALDH2 G/A(OR=1.70,95%CI:1.08～2.68)基因型者患食道癌危险性明显增加,以携带ALDH2A/A的饮酒者最为显著(OR=8.63,95%CI:2.07～35.95).(2)无论是否饮酒,携带不同ADH2基因型者之间患食道癌的风险差异均无统计学意义.(3)携带ALDH2 A/A或G/A基因型者,不论同时携带何种ADH2基因型患食道癌的风险均显著增加,且作用效应为ALDH2 A/A≥G/A.(4)与同时携带ALDH2 G/G和ADH2 A/A的不饮酒者相比,同时携带ALDH2 G/A或A/A和ADH2 G/A或G/G的饮酒者,患食道癌危险性OR值高达8.36(95%CI:2.98～23.46).结论 饮酒及醇醛脱氢酶基因多态与食道癌的联系主要与ALDH2有关;携带ALDH2A/A和G/A者减少酒精消耗量,有助于降低患食道癌危险性.     

GSTM1基因多态性和环境因素的交互作用与食管癌关系的研究

[目的]探讨GSTM1基因多态位点和环境因素的交互作用与新疆地区汉族食管癌之间的关系。[方法]采用病例对照的研究方法,应用聚合酶链式反应——连接酶检测反应(PCR-LDR)技术,分别对GSTM1基因缺失型和rs2071487两个多态位点进行检测。[结果]GSTM1基因缺失/非缺失基因型在病例组和对照组之间的分布差异有统计学意义(χ2=14.67,P=0.000),即携带缺失型基因型者发生食管癌的风险增加(OR=3.01,95%CI:1.71～5.30));GSTM1缺失基因型分别与常吃熏肉、常吃酸菜之间存在正向交互作用(γ﹥1),即常吃熏肉且GSTM1缺失基因型者发生食管癌的危险性是不吃或偶尔吃熏肉的非缺失基因型者的32.51倍(OR95%CI:13.06～80.95);常吃酸菜且GSTM1缺失基因型者发生食管癌的危险性是不吃或偶尔吃酸菜的非缺失基因型者的18.37倍(OR95%CI:7.76～43.48)。[结论GSTM1缺失基因型和环境危险因素之间在食管癌的发生中存在交互效应,基因对环境危害效应具有放大作用。     

细胞色素P4501A1基因多态性与食管癌易感性关系的Meta分析

目的 探讨细胞色素P4501A1(CYP1A1)MspI和Ile/Val位点基因多态性与食管癌发生的关系.方法 采用Meta分析方法,对国内外1997-2008年采用病例对照方法研究CYP1A1MspI和Ile/Val基因多态性与食管癌发生关系的16篇(MspI 8篇,Ile/Val 14篇)文献,采用显性模型(即突变基因型与野生型比较)进行综合定量分析,然后按病理分型(鳞癌/腺癌)分亚组进行分析.结果 综合分析CYP1A1 MspI突变基因型(TC+CC)与食管癌发生无统计学关联(OR=1.17,95%CI:0.82～1.66),亚组分析亦未发现CYP1A1 MspI突变基因型与食管鳞癌(OR=1.17,95%CI:0.82～1.69)和食管腺癌(OR=1.39,95%CI:0.67～2.09)的统计学关联;携带CYP1A1突变基因型(Ile/Val+Val/Val)的个体发生食管癌的危险性是野生型的1.39倍(OR=1.39,95%CI:1.07～1.80);亚组分析显示突变基因型与食管鳞癌发生的易感性相关但与食管腺癌无关联,OR值分别为1.43(95%CI:1.07～1.91)和1.20(95%CI:0.62～2.30).结论 CYP1A1 Ile/Val位点突变基因型可增加食管鳞癌发生的危险性,CYP1A1 MspI位点基因多态性与食管癌无关联.