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1.
J Food Prot ; 69(7): 1616-22, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16865895

RESUMEN

The effectiveness of electrolyzed oxidizing anode (EOA) water (oxidation-reduction potential, 1,120 mV; pH 2.0) as a sanitizer for use in abattoirs was compared with the iodophor (IOD) Mikroklene (25 ppm), a sanitizer approved for use by regulatory authorities in Canada and the United States. A total of 240 swab (100 cm2) samples were obtained from 4 sites on the kill floor and 16 sites in the secondary processing areas, during two visits within a 4-week period to each of three meat packing plants, processing < or =50 animals per week. Swabs were obtained 12 h after the application of IOD and EOA and were analyzed for the presence of total aerobic bacteria, total coliforms, and total Escherichia coli. Total aerobic bacteria (log CFU/ 100 cm2) recovered from the 20 sample sites were lower (P < 0.0001) in EOA as compared with IOD (2.94 +/- 0.12 versus 3.75 +/- 0.12, respectively). Plant A was 1.5 times more likely (P < 0.0001) to have a sampling site positive for the presence of coliforms and E. coli than plants B and C. There was no difference (P > 0.05) between treatment IOD or EOA in the likelihood of obtaining a positive sample for the presence of total coliforms or E. coli among the three plants. When the kill floor and secondary processing areas are compared, the likelihood of obtaining a sample positive for coliforms or E. coli was similar (P > or = 0.05). Results indicate that EOA was more effective than IOD in reducing populations of total aerobic bacteria on equipment surfaces in the three meat packing plants studied. Because the likelihood of obtaining a positive sample for coliforms or E. coli in EOA as compared with IOD was similar, EOA may be a suitable alternative or complement to IOD as a sanitizer in small- to medium-sized abattoirs. Additional research is required to further evaluate the effectiveness of EOA to sanitize processing equipment on the basis of subsequent isolation of aerobes, coliforms, and E. coli from meat products.


Asunto(s)
Mataderos/normas , Desinfección/métodos , Contaminación de Equipos , Yodóforos/farmacología , Agua/química , Animales , Bacterias Aerobias/efectos de los fármacos , Bacterias Aerobias/crecimiento & desarrollo , Recuento de Colonia Microbiana , Electrólisis , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/crecimiento & desarrollo , Contaminación de Equipos/prevención & control , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Contaminación de Alimentos/prevención & control , Microbiología de Alimentos , Oxidación-Reducción , Agua/farmacología
2.
Eur J Clin Nutr ; 60(4): 561-5, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16391574

RESUMEN

OBJECTIVE: We assessed the extent of energy misreporting from the use of a self-administered 7-day diet record (7-DDR) and a widely used food frequency questionnaire (FFQ) compared to total energy expenditure from doubly labeled water (DLW) in a group of postmenopausal women. DESIGN: At baseline, 65 healthy postmenopausal women were instructed to fill out the National Cancer Institute's (NCI) FFQ and a 7-DDR. Average total energy expenditure using the DLW method was also performed at baseline. RESULTS: On average, the women underestimated total energy intake compared to total energy expenditure assessed from DLW by 37% on the 7-DDR and 42% on the FFQ. CONCLUSIONS: These findings suggest that the interpretation of findings from the 7-DDR- and FFQ-based energy-disease association studies in postmenopausal women needs further evaluation. SPONSORSHIP: This research was supported (in part) by the Intramural Program of the NIH (National Cancer Institute).


Asunto(s)
Agua Corporal/metabolismo , Registros de Dieta , Ingestión de Energía , Encuestas y Cuestionarios , Mujeres/psicología , Anciano , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad , Posmenopausia , Autorrevelación , Sensibilidad y Especificidad
3.
J Infect Dis ; 184(8): 992-7, 2001 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-11574913

RESUMEN

Trimethoprim-sulfamethoxazole (TMP-SMZ) is the most effective Pneumocystis carinii pneumonia (PCP) prophylactic agent, but adverse reactions are common among human immunodeficiency virus (HIV)-infected patients and limit its use. This randomized, double-blind controlled trial compared 2 methods of TMP-SMZ reintroduction, 6-day dose escalation and direct rechallenge, for PCP prophylaxis in HIV-infected patients who had experienced previous treatment-limiting reactions. The primary end point was the ability to take single-strength TMP-SMZ daily for 6 months. Seventy-five percent of the dose-escalation group and 57% of the direct-rechallenge group continued to receive daily single-strength TMP-SMZ for 6 months (P= .014). Among premature discontinuations, 58% of the dose-escalation group and 70% of the direct-rechallenge group were due to adverse reactions. None of these reactions was serious. This study provides evidence that it is possible to successfully reintroduce TMP-SMZ to a significant proportion of HIV-infected patients who have experienced mild-to-moderate treatment-limiting adverse reactions.


Asunto(s)
Terapia Antirretroviral Altamente Activa/efectos adversos , Infecciones por VIH/tratamiento farmacológico , Neumonía por Pneumocystis/prevención & control , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Adulto , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Infecciones por VIH/transmisión , Humanos , Masculino , Persona de Mediana Edad , Selección de Paciente , Grupos Raciales , Resultado del Tratamiento , Combinación Trimetoprim y Sulfametoxazol/efectos adversos
4.
Genes Chromosomes Cancer ; 31(4): 390-7, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11433530

RESUMEN

Allelic loss on chromosome 13 occurs frequently in esophageal squamous cell carcinoma. However, studies of the two known tumor suppressor genes located on 13q, RB1 and BRCA2, have shown few mutations, suggesting that other genes are likely to be involved in the development of this tumor type. To identify a minimal deletion interval, we first analyzed 42 microsatellite markers spanning chromosome bands 13q11-q13 in 56 esophageal squamous cell carcinoma patients, including 34 with a family history of upper gastrointestinal cancer and 22 without a family history of cancer. Lifestyle risk factors and clinical/pathologic characteristics were also collected. Two commonly deleted regions were identified: one was located on band 13q12.11, between markers D13S787 and D13S221; the other was located on bands 13q12.3-q13.1 from markers D13S267 to D13S219. We observed higher allelic loss frequencies for eight of the microsatellite markers in those patients with a family history of upper gastrointestinal cancer compared to patients without such a history. This study suggests that one or more unidentified tumor suppressor genes are located on chromosome arm 13q that play a role in the development of esophageal squamous cell carcinoma.


Asunto(s)
Carcinoma de Células Escamosas/genética , Bandeo Cromosómico , Cromosomas Humanos Par 13/genética , Neoplasias Esofágicas/genética , Pérdida de Heterocigocidad/genética , Humanos , Repeticiones de Microsatélite/genética
5.
J Natl Cancer Inst ; 93(9): 710-5, 2001 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-11333294

RESUMEN

BACKGROUND: Alcohol ingestion is associated with an increased risk of breast cancer in most epidemiologic studies. Results, however, are heterogeneous at lower levels of alcohol intake, and a biologic mechanism for the association has not been clearly identified. To determine whether alcohol consumption by postmenopausal women elevates serum levels of hormones associated with an increased risk of breast cancer, we performed a controlled feeding study. METHODS: Participants were 51 healthy postmenopausal women not using hormone replacement therapy. Each participant rotated through three 8-week dietary periods in which she consumed 15 or 30 g of alcohol per day or an alcohol-free placebo beverage. The order of assignment to the three alcohol levels was random. During the dietary periods, all food and beverages were supplied by the study, and energy intake was adjusted to keep body weight constant. Levels of estradiol, estrone, estrone sulfate, testosterone, androstenedione, progesterone, dehydroepiandrosterone (DHEA), DHEA sulfate (DHEAS), and androstenediol were measured by radioimmunoassays in serum collected at the end of each dietary period. All statistical tests are two-sided. RESULTS: When women consumed 15 or 30 g of alcohol per day, respectively, estrone sulfate concentrations increased by 7.5% (95% confidence interval [CI] = -0.3% to 15.9%; P =.06) and 10.7% (95% CI = 2.7% to 19.3%; P =.009) and DHEAS concentrations increased by 5.1% (95% CI = 1.4% to 9.0%; P =.008) and 7.5% (95% CI = 3.7% to 11.5%; P<.001) relative to levels when women consumed placebo. None of the other hormones measured changed statistically significantly when women consumed alcohol. CONCLUSIONS: Results suggest a possible mechanism by which consumption of one or two alcoholic drinks per day by postmenopausal women could increase their risk of breast cancer.


Asunto(s)
Neoplasias de la Mama/inducido químicamente , Etanol/efectos adversos , Hormonas Esteroides Gonadales/sangre , Posmenopausia/sangre , Anciano , Deshidroepiandrosterona/sangre , Sulfato de Deshidroepiandrosterona/sangre , Terapia de Reemplazo de Estrógeno , Femenino , Humanos , Persona de Mediana Edad , Globulina de Unión a Hormona Sexual/análisis
6.
Clin Cancer Res ; 7(4): 883-91, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11309337

RESUMEN

Esophageal squamous cell carcinoma (ESCC) is one of the most common fatal cancers worldwide, and north central China has some of the highest rates in the world. Previous studies from tumors in this area of China have shown high frequencies of allelic loss on chromosome 17p13-11, which includes the region where the TP53 gene is found. We examined 56 ESCC patients using single-strand conformation polymorphism and DNA sequencing to assess the frequency and spectrum of TP53 mutation and the association between allelic loss at microsatellite marker TP53 and TP53 mutations. Ninety-six % of cases were found to have at least one genetic alteration, including TP53 mutation (77%), allelic loss within the TP53 gene (73%), and/or loss of heterozygosity at the TP53 microsatellite marker (80%); 75% had two or more such alterations, including 59% with both a point mutation and an intragenic allelic loss ("two hits"). The majority of mutations observed were in exon 5, where the most common type of nucleotide substitution was a G:C-->A:T or C:G-->T:A transition, including half that occurred at CpG sites. Allelic loss was most commonly found in exon 4 but was very common in exon 5 as well. Taken together, the multiple genetic alterations of TP53 in this population at high risk for ESCC indicate that there is a very high degree of genetic instability in these tumors, that TP53 is a primary target for inactivation, and that this tumor suppressor gene plays a critical role in the carcinogenesis process for ESCC.


Asunto(s)
Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Proteína p53 Supresora de Tumor/genética , Adulto , Anciano , China/epidemiología , Exones , Femenino , Frecuencia de los Genes , Silenciador del Gen , Marcadores Genéticos , Humanos , Pérdida de Heterocigocidad , Masculino , Persona de Mediana Edad , Mutación , Polimorfismo Genético , Factores de Riesgo
7.
Cancer Epidemiol Biomarkers Prev ; 10(2): 119-23, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11219768

RESUMEN

We explored the association between polymorphisms of the DNA repair gene XRCC1 (codons 194, 280, and 399) and lung cancer risk in a case-control study nested within a cohort of tin miners. Cases were those diagnosed with lung cancer over 6 years of follow-up (n = 108). Two controls, matched on age and sex, were selected for each case by incidence density sampling. Of the three polymorphisms, only the XRCC1 Arg280His allele was associated with increased lung cancer risk (odds ratio, 1.8; 95% confidence interval, 1.0-3.4) after adjustment for radon and tobacco exposure. In addition, individuals with the variant Arg280His allele who were alcohol drinkers seemed to be at higher risk for lung cancer compared with those with the homozygous wild-type genotype. Conversely, individuals with the variant Arg194Trp allele who were alcohol drinkers seemed to be at lower risk for lung cancer compared with those with the homozygous wild-type genotype. Polymorphisms of XRCC1 appear to influence risk of lung cancer and may modify risk attributable to environmental exposures.


Asunto(s)
Proteínas de Unión al ADN/genética , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/genética , Polimorfismo Genético , Adulto , Distribución por Edad , Anciano , Secuencia de Bases , Estudios de Casos y Controles , Estudios de Cohortes , Intervalos de Confianza , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Estudios Prospectivos , Factores de Riesgo , Distribución por Sexo , Tasa de Supervivencia , Estados Unidos/epidemiología , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X
8.
Carcinogenesis ; 21(11): 2019-26, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11062163

RESUMEN

Allelic loss on chromosome 17p has been reported frequently in esophageal squamous cell carcinoma (ESCC) and generally encompasses the p53 locus at 17p13.1. However, a good correlation between allelic loss on 17p and mutation of p53 has not been found. This suggests the possibility that unknown tumor suppressor genes near p53 may be involved in the development of ESCC. To evaluate this possibility, we analyzed 30 microsatellite markers covering the entire short arm of chromosome 17 in 56 ESCC patients from a high risk population in northern China, including 34 with a family history of upper gastrointestinal (UGI) cancer and 22 without a family history of any cancer. Cancer lifestyle risk factors and clinical/pathological characteristics were also collected. We found frequent allelic loss (>/=65%) at 28 of the 30 markers evaluated in these ESCC patients. The highest frequencies of allelic loss (> or =80%) were found in three smaller regions: deletion region I located at 17p13.3-p13.2 (between D17S849 and D17S1828); deletion region II located at 17p13.2-p13.1 (between D13S938 and TP53); deletion region III located at 17p13.1-p12 (between D17S804 and D17S799). A number of genes have already been identified in these deleted regions, including: OVCA1, OVCA2 and HIC-1 in deletion region I; p53 in deletion region II; ZNF18, ZNF29, ALDH3 and ALDH10 in deletion region III. These results will help us direct future testing of candidate genes and narrow the search region for major new tumor suppressor genes that may play a role in the pathogenesis of ESCC.


Asunto(s)
Carcinoma de Células Escamosas/genética , Cromosomas Humanos Par 17 , Neoplasias Esofágicas/genética , Pérdida de Heterocigocidad , Adulto , Anciano , Carcinoma de Células Escamosas/epidemiología , China/epidemiología , Neoplasias Esofágicas/epidemiología , Femenino , Humanos , Incidencia , Estilo de Vida , Masculino , Repeticiones de Microsatélite , Persona de Mediana Edad , Factores de Riesgo , Factores Sexuales
9.
Alcohol Alcohol ; 35(4): 355-60, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10906000

RESUMEN

To examine the association between pre-diagnostic serum carotenoid levels and lung cancer risk and the effects of alcohol intake on the carotenoid-lung cancer relationship, we conducted a case-control study in an occupational cohort from the Yunnan Tin Corporation in China. During 6 years of follow-up, 339 cases of confirmed lung cancer were diagnosed. Among these cases, those who donated pre-diagnostic blood (n = 108) were eligible for this study. For each case, two individuals alive and free of cancer at the time of case diagnosis, matched on age, sex, and date of blood collection, were selected as controls. Serum beta-carotene (odds ratios (ORs) for tertiles: 1, 1.3, 2.0) and beta-cryptoxanthin (ORs for tertiles: 1, 1.8, 2.9) levels were positively associated with lung cancer risk after adjustment for tobacco use and radon exposure. Among alcohol drinkers, higher serum carotenoid levels were significantly associated with increased lung cancer risk (alpha-carotene OR 2.2, 95% confidence interval (CI) 1.1-4.4, beta-carotene OR 7.6, 95% CI 3.1-18.6, lutein/zeaxanthin OR 2.3, 95% CI 1.2-6.6 and beta-cryptoxanthin OR 7.6, 95% CI 2.7-21.5). Conversely, risk estimates among non-drinkers suggest a possible protective association for higher carotenoid levels.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Neoplasias Pulmonares/sangre , Minería , Estaño , beta Caroteno/sangre , Adulto , Anciano , Estudios de Casos y Controles , China/epidemiología , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo
10.
Cancer Causes Control ; 11(2): 129-35, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10710196

RESUMEN

OBJECTIVE: To evaluate the association of prediagnostic serum antioxidants and lung cancer risk we conducted a case-control study nested in an occupational cohort of tin miners. METHODS: Male workers free of cancer enrolled in the cohort. During up to 6 years of follow-up, 339 lung cancer cases were diagnosed and, among these cases, those who donated blood prospectively (n = 108) were eligible for this study. For each case, two controls alive and free of cancer at the time of case diagnosis were matched on age and date of blood collection. RESULTS: Overall, we observed no association between serum alpha-tocopherol, gamma-tocopherol or selenium levels and lung cancer risk. However, a significant gradient of decreasing lung cancer risk with increasing serum alpha-tocopherol was apparent for men less than 60 years old (odds ratio by tertile: 1.0, 0.9, 0.2; trend p = 0.002). Alpha-tocopherol was also protective in men who reported no alcohol drinking (OR by tertile: 1.0, 0.6, 0.3; trend p = 0.008). CONCLUSION: Although there were no significant overall associations between prospectively collected serum alpha-tocopherol, gamma-tocopherol or selenium and incidence of lung cancer, results from this study suggest that higher alpha-tocopherol levels may be protective in men less than 60 years old and in those who do not drink alcohol.


Asunto(s)
Biomarcadores de Tumor/sangre , Neoplasias Pulmonares/epidemiología , Minería , Enfermedades Profesionales/epidemiología , Selenio/sangre , Vitamina E/sangre , Adulto , Distribución por Edad , Anciano , Estudios de Casos y Controles , China/epidemiología , Estudios de Cohortes , Monitoreo del Ambiente , Monitoreo Epidemiológico , Humanos , Incidencia , Modelos Logísticos , Estudios Longitudinales , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/etiología , Masculino , Persona de Mediana Edad , Radón/análisis , Medición de Riesgo , Sensibilidad y Especificidad , Estadísticas no Paramétricas , Estaño
11.
Genes Chromosomes Cancer ; 27(3): 217-28, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10679910

RESUMEN

Esophageal cancer is one of the most common fatal cancers worldwide. Deletions of genomic regions are thought to be important in esophageal carcinogenesis. We conducted a genomewide scan for regions of allelic loss using microdissected DNA from 11 esophageal squamous-cell carcinoma patients with a family history of upper gastrointestinal tract cancer from a high-risk region in north central China. Allelic patterns of 366 fluorescently labeled microsatellite markers distributed at 10-cM intervals over the 22 autosomal chromosomes were examined. We identified 14 regions with very high frequency (>/= 75%) loss of heterozygosity (LOH), including broad regions encompassing whole chromosome arms (on 3p, 5q, 9p, 9q, and 13q), regions of intermediate size (on 2q, 4p, 11p, and 15q), and more discrete regions identified by very high frequency LOH for a single marker (on 4q, 6q, 8p, 14q, and 17p). Among these 14 regions were 7 not previously described in esophageal squamous-cell carcinoma as having very high frequency LOH (on 2q, 4p, 4q, 6q, 8p, 14q, and 15q). The very high frequency LOH regions identified here may point to major susceptibility genes, including potential tumor suppressor genes and inherited gene loci, which will assist in understanding the molecular events involved in esophageal carcinogenesis and may help in the development of markers for genetic susceptibility testing and screening for the early detection of this cancer. Genes Chromosomes Cancer 27:217-228, 2000. Published 2000 Wiley-Liss, Inc.


Asunto(s)
Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Genoma Humano , Pérdida de Heterocigocidad/genética , Adulto , Carcinoma de Células Escamosas/epidemiología , China/epidemiología , Cromosomas Humanos/genética , Neoplasias Esofágicas/epidemiología , Femenino , Marcadores Genéticos/genética , Humanos , Masculino , Repeticiones de Microsatélite/genética , Persona de Mediana Edad , Factores de Riesgo
12.
Clin Cancer Res ; 5(11): 3476-82, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10589761

RESUMEN

Chromosomal regions with frequent allelic loss may point to major susceptibility genes that will assist in understanding molecular events involved in esophageal carcinogenesis. Esophageal squamous cell carcinoma samples and blood from 46 patients, including 23 patients with and 23 patients without a family history of upper gastrointestinal cancer, were screened using laser microdissected DNA and tested for loss of heterozygosity (LOH) at 18 marker loci representing 14 chromosomal regions (on 2q, 3p, 4p, 4p, 5q, 6q, 8p, 9p, 9q, 11p, 13q, 14q, 15q, and 17p) identified in an earlier genome-wide scan to have frequent LOH. Clinical/pathological and lifestyle risk factor data were also collected. For all 46 tumors combined, the lowest frequency LOH for any of the 18 markers was 37%, and 8 markers showed LOH in > or =75% of informative tumors. One marker (D13S894 on 13q) showed greater LOH in patients with a positive family history (93% versus 50%; P = 0.04), whereas two markers (D6S1027 on 6q and D9S910 on 9q) had significantly more LOH in patients with metastasis, and one marker (D4S2361 on 4p) showed significantly higher LOH in patients with a lower pathological tumor grade. No relation was seen between LOH and lifestyle risk factors. This study confirms the previously observed high frequency LOH for these 14 chromosomal regions, including a locus on 13q where LOH is more common in patients with a family history of upper gastrointestinal cancer than in those without such history, suggesting that a gene in this area may be involved in genetic susceptibility to esophageal cancer.


Asunto(s)
Carcinoma de Células Escamosas/genética , Mapeo Cromosómico , Cromosomas Humanos , Neoplasias Esofágicas/genética , Neoplasias Gastrointestinales/genética , Pérdida de Heterocigocidad , Adulto , Anciano , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/patología , China/epidemiología , Neoplasias Esofágicas/epidemiología , Neoplasias Esofágicas/patología , Familia , Femenino , Marcadores Genéticos , Predisposición Genética a la Enfermedad , Humanos , Estilo de Vida , Metástasis Linfática , Masculino , Repeticiones de Microsatélite , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Factores de Riesgo
13.
Hum Pathol ; 29(11): 1294-8, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9824110

RESUMEN

Esophageal cancer is one of the most fatal cancers worldwide and is characterized by great variation in rates among different populations. Linxian, a county in Henan Province, located in north-central China, has one of the highest rates of esophageal squamous cell carcinoma in the world. Most squamous cell carcinomas in low-risk populations are attributable to alcohol and tobacco consumption, but the causative agents in high-risk populations are less clear. The prevention and treatment of esophageal cancer in high-risk regions, such as Linxian, are limited by our inability to identify these agent(s). During a preliminary histological review, the authors noticed characteristic findings in the arteries, nerves, and lymph nodes of esophagectomy specimens from Linxian and wondered whether these findings might offer clues to the cause of squamous cell carcinoma (eg, polycyclic aromatic hydrocarbon exposure) in the Linxian population. The purpose of this study was to report these previously undescribed histopathologic changes and to compare their presence and severity with those found in esophageal squamous cell carcinomas and adenocarcinomas from a lower-risk population in the United States. Forty esophagectomies were reviewed, including 13 squamous cell carcinomas from Linxian and 21 squamous cell carcinomas and six adenocarcinomas from the United States. The presence and severity of arteriosclerosis and myxoid degeneration of nerves and the presence of anthracosis in periesophageal lymph nodes were recorded. The prevalence and severity of these findings in the three groups of esophagectomies were compared. The esophageal squamous cell carcinomas from Linxian, China, had a higher prevalence of arteriosclerotic vessels, nerves with myxoid degeneration, and anthracotic lymph nodes than the squamous cell carcinomas from the United States (Wilcoxon test, P < .04 for all comparisons). There were also significant differences in the prevalence of arteriosclerotic vessels and anthracotic lymph nodes between the esophageal squamous cell carcinomas from Linxian and the adenocarcinomas from the United States. Arteriosclerosis and the myxoid degeneration were significantly more severe in the esophageal squamous cell carcinomas from Linxian than in the esophageal squamous cell carcinomas or adenocarcinomas from the United States (Mantel trend test, P < .006 for all comparisons). Arteriosclerotic vessels, nerves with myxoid degeneration, and anthracotic lymph nodes can be seen in association with esophageal squamous cell carcinomas from the high-risk region of Linxian, China. These changes appear to be more prevalent and severe than those seen in association with esophageal squamous cell carcinomas or adenocarcinomas from a low-risk population in the United States. These characteristic changes may be causatively significant and may represent histological evidence of high-level environmental exposure to polycyclic aromatic hydrocarbons.


Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/patología , Adenocarcinoma/patología , Anciano , Arteriosclerosis/patología , Carcinoma de Células Escamosas/irrigación sanguínea , Carcinoma de Células Escamosas/epidemiología , China/epidemiología , Neoplasias Esofágicas/irrigación sanguínea , Neoplasias Esofágicas/epidemiología , Esofagectomía , Esófago/irrigación sanguínea , Esófago/inervación , Femenino , Humanos , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , Factores de Riesgo , Estados Unidos
14.
Ann Epidemiol ; 7(8): 533-41, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9408549

RESUMEN

PURPOSE: To examine risk factors and establish a biologic specimen and data bank for the study of early markers of lung cancer. METHODS: We designed a dynamic cohort using an ongoing lung cancer screening program among radon- and arsenic-exposed tin miners in Yunnan China. Through the first four years of the study, 8,346 miners aged 40 years and older with over 10 years of occupational exposure have been enrolled, risk factors have been assessed, annual sputum and chest radiographs have been obtained, and numerous biologic specimens have been collected. RESULTS: A total of 243 new lung cancer cases have been identified through 1995. Radon and arsenic exposures are the predominant risk factors, but lung cancer risk is also associated with chronic bronchitis and silicosis, as well as a number of exposure to tobacco smoke, including early age of first use, duration, and cumulative exposure. Tumor and sputum samples are being examined for early markers of lung cancer. CONCLUSION: A cohort of occupationally-exposed tin miners with an extensive biologic specimen repository has been successfully established to simultaneously study the etiology and early detection of lung cancer.


Asunto(s)
Neoplasias Pulmonares/epidemiología , Minería , Enfermedades Profesionales/epidemiología , Estaño , Adulto , Anciano , Arsénico/efectos adversos , China/epidemiología , Estudios de Cohortes , Femenino , Humanos , Incidencia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/etiología , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/diagnóstico , Enfermedades Profesionales/etiología , Radón/efectos adversos , Factores de Riesgo , Fumar/efectos adversos , Encuestas y Cuestionarios
15.
Cancer ; 80(11): 2047-59, 1997 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-9392326

RESUMEN

BACKGROUND: The principal reason for the poor prognosis of esophageal carcinoma is that most tumors are asymptomatic and go undetected until they are unresectable. Previous studies have shown that cytologic screening of asymptomatic high risk individuals can detect curable esophageal carcinomas and precursor lesions, but the sensitivity of such screening is not well documented. The current study evaluated the sensitivity and specificity of currently available balloon and sponge cytologic samplers for detecting biopsy-proven squamous dysplasia and carcinoma in asymptomatic individuals from a high risk population in Linxian, China. METHODS: Asymptomatic adults were examined with both balloon and sponge samplers, in random order, followed by endoscopy with mucosal iodine staining and biopsy of all unstained lesions. The cytology slides were interpreted using the criteria of the Bethesda System. The balloon and sponge cytologic diagnoses (test) were compared with the biopsy diagnosis (truth) in each patient to estimate the sensitivity and specificity of each sampler. RESULTS: Of the 439 patients with adequate biopsies, 123 (28%) had histologic squamous dysplasia and 16 (4%) had an invasive squamous carcinoma. The sensitivities/specificities of the balloon and sponge were 44%/99% and 18%/100%, respectively, for detecting biopsy-proven squamous cell carcinoma, and 47%/81% and 24%/92%, respectively, for identifying squamous dysplasia or carcinoma. CONCLUSIONS: In this study, the balloon sampler was more sensitive than the sponge sampler for detecting esophageal squamous disease, but both techniques were less than optimal. Improved samplers and/or cytologic criteria should increase the sensitivities observed in this baseline study.


Asunto(s)
Biopsia/instrumentación , Carcinoma de Células Escamosas/prevención & control , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/prevención & control , Lesiones Precancerosas/diagnóstico , Adulto , Biopsia/métodos , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patología , China , Neoplasias Esofágicas/patología , Esofagoscopía , Humanos , Persona de Mediana Edad , Lesiones Precancerosas/patología , Lesiones Precancerosas/prevención & control , Sensibilidad y Especificidad
16.
Cancer Epidemiol Biomarkers Prev ; 6(11): 893-900, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9367062

RESUMEN

We initiated the present study to evaluate the accuracy of a new epithelial biomarker of early lung cancer. We tested the hypothesis that expression of a tumor-associated antigen by exfoliated sputum epithelial cells has greater accuracy (sensitivity and specificity) for the detection of preclinical, localized lung cancer than do routine clinical detection methods. Monoclonal antibody (MAb) 703D4 recognizes heterogeneous nuclear ribonuclear protein (hnRNP) A2/B1. We compared the accuracy of hnRNP up-regulation with cytology and radiographic screening for lung cancer detection in miners who were highly exposed to tobacco smoke, radon, and arsenic in southwestern China. The results showed that MAb 703D4 detection of hnRNP expression by sputum epithelial cells had greater accuracy for the detection of lung cancer than did routine screening methods, particularly for early (localized) disease. Among 57 cases and 76 noncases at the first screening, overall MAb detection of hnRNP was more sensitive (74 versus 21% for cytology and 42% for chest x-ray) but had lower specificity (70 versus 100% for cytology and 90% for chest x-ray) than standard methods. Recognizing hnRNP up-regulation resulted in detection of approximately one-third more early cases than did the combination of X-ray and cytology. Detection of hnRNP A2/B1 expression appears to be a good initial screening test for lung carcinogenesis, as it identified 74% of those who developed subsequent clinical lung cancer. Future studies might separate individuals with high lung cancer risk by MAb detection, confirming the positives with markers having greater specificity (e.g., clinical studies that become positive later in the morphological progression).


Asunto(s)
Biomarcadores de Tumor/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B , Neoplasias Pulmonares/metabolismo , Proteínas de Neoplasias/metabolismo , Enfermedades Profesionales/metabolismo , Ribonucleoproteínas/metabolismo , Esputo/metabolismo , Adulto , Anciano , Anticuerpos Monoclonales , Arsénico , Estudios de Casos y Controles , China , Células Epiteliales/metabolismo , Ribonucleoproteínas Nucleares Heterogéneas , Humanos , Técnicas para Inmunoenzimas , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/prevención & control , Tamizaje Masivo , Persona de Mediana Edad , Minería , Enfermedades Profesionales/diagnóstico , Enfermedades Profesionales/prevención & control , Exposición Profesional , Radón , Sensibilidad y Especificidad , Esputo/citología , Estaño , Contaminación por Humo de Tabaco
17.
Am J Epidemiol ; 145(8): 746-51, 1997 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-9126001

RESUMEN

The use of proxy respondents in surveys designed to provide population estimates of smoking prevalence offers an inexpensive way to obtain these data. The accuracy of this information is examined in analyzing data from tobacco use surveys of adults conducted in 22 North American communities as part of the National Cancer Institute's Community Intervention Trial for Smoking Cessation. Proxy-reported smoking status was obtained in a cross-sectional telephone survey conducted from August 1993 to January 1994 (n = 99,682). Self-reported smoking status was obtained from an in-depth interview of a sample of the respondents aged 25-64 years enumerated from the telephone survey (n = 31,417). Discrepancy rates were calculated by comparing the proxy-reported and self-reported smoking statuses of a given individual (n = 10,226). In both surveys, respondents were categorized as current smokers (those who currently smoke and have smoked at least 100 cigarettes in their lifetime), recent quitters (< or = 8 years since cessation), long-term quitters (> 8 years since cessation), and never smokers. The overall discrepancy rate between the self-report and the proxy report was 5.4%. Self-respondents who were black, Hispanic, Asian, recent quitters, or aged 25-34 years were more likely to have inconsistent proxy reports. The authors estimate that the screener interview underestimated the true smoking prevalence by 0.1% when they corrected for smoking status discrepancies. These results confirm that proxy-reported smoking status is an accurate and effective means to monitor populationwide smoking prevalence of adults.


Asunto(s)
Recolección de Datos/métodos , Fumar/epidemiología , Adulto , Canadá/epidemiología , Factores de Confusión Epidemiológicos , Estudios Transversales , Femenino , Humanos , Masculino , Prevalencia , Autorrevelación , Encuestas y Cuestionarios , Estados Unidos/epidemiología
18.
Tob Control ; 6 Suppl 2: S49-56, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9583653

RESUMEN

OBJECTIVE: To compare tobacco control practices of physicians and their staff in Intervention communities with those in Comparison communities of the Community Intervention Trial for Smoking Cessation (COMMIT). DESIGN: COMMIT was a randomised trial testing community-based intervention for smoking cessation carried out over four years. SETTING: Eleven matched pairs of communities assigned randomly to Intervention and Comparison conditions. PARTICIPANTS AND INTERVENTIONS: Physicians in the Intervention communities participated in continuing medical education (CME). Training for office staff focused on tobacco control and office intervention "systems". OUTCOME MEASURES: Smoking control attitudes and practices reported by primary-care physicians in the 22 communities, smoking policies, and practices of 30 randomly selected medical offices in each community, and patient reports of physician intervention activities. RESULTS: Response rates to the physicians' mail survey were 45% and 42% in Intervention and Comparison communities, respectively. Telephone interviews of office staff had response rates of 84% in both conditions. Physicians in Intervention communities were more likely to attend training than those in Comparison communities (53% and 26%, respectively (P<0.0005)). In both conditions, training attendees perceived themselves as being better prepared to counsel smokers than non-attendees (P < or = 0.01) and reported more activity in smoking intervention. Intervention communities carried out more office-based tobacco control activities (P = 0.002). Smokers in Intervention communities were more likely to report receiving reading material about smoking from their physicians (P = 0.026). No other differences in physician intervention activities were reported by smokers between the Intervention and Comparison communities. CONCLUSIONS: The COMMIT intervention had a significant effect on some reported physician behaviours, office practices, and policies. However, most physicians still did not use state-of-the-art smoking intervention practices with their patients and there was little, or no, difference between patient reports of intervention activities of physicians in the Intervention and Comparison communities. Better systems and incentives are needed to attract physicians and their staff to CME and to encourage them to follow through on what they learn. The recently released Agency for Health Care Policy and Research clinical practice guideline for smoking cessation and other standards and policies outline these systems and offer suggestions for incentives to facilitate adoption of these practices by physicians.


Asunto(s)
Promoción de la Salud , Nicotiana , Plantas Tóxicas , Atención Primaria de Salud , Tabaquismo/prevención & control , Adulto , Estudios de Cohortes , Femenino , Humanos , Masculino , Estudios Retrospectivos , Encuestas y Cuestionarios , Tabaquismo/epidemiología , Estados Unidos/epidemiología
19.
Prev Med ; 25(2): 186-94, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8860284

RESUMEN

BACKGROUND: As an important aspect of the COMMIT trial, worksite smoking-control consultations and supports were provided to employers in 11 diverse, moderate-sized communities. After a 4-year intervention period (1989-1992), impacts on worksite policies, support resources for smokers, and employee perceptions were assessed in these communities and in 11 matched Comparison communities. METHODS: Data from two surveys are reported here. In each of the 22 COMMIT communities, a sample of worksites within each of four size strata were surveyed to determine worksite policies, activities, and resources regarding smoking. Data from employees were obtained from independent community-wide surveys of community residents. RESULTS: Overall, 44% of the worksites surveyed reported having smoke-free policies, with no differences between Intervention and Comparison communities. Thirty-seven percent of Intervention community work-sites reported offering smoking cessation resources or assistance for employees during the period of the study, compared to 31% of Comparison community worksites (P = 0.04). Employees in Intervention communities, relative to those in Comparison communities, reported greater awareness of stop-smoking resources, but equivalent increases in worksite smoking bans. CONCLUSION: Although the level of worksite smoking-cessation activities was higher in Intervention than in Comparison communities, there remains a substantial need to increase the level of such activities and to integrate such activities with restrictive smoking policies.


Asunto(s)
Política de Salud , Promoción de la Salud/organización & administración , Servicios de Salud del Trabajador/organización & administración , Cese del Hábito de Fumar , Lugar de Trabajo , Humanos , América del Norte , Prevalencia , Evaluación de Programas y Proyectos de Salud
20.
Arch Fam Med ; 3(4): 341-8, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8012622

RESUMEN

OBJECTIVE: To obtain a baseline measure of tobacco control activities carried out by physicians and of tobacco control policies and practices in physician offices. DESIGN: All primary care physicians in 11 communities were asked through a mail survey about their tobacco control practices. Thirty offices in each community were randomly selected and interviewed by telephone to determine office policies and practices. SETTING: Both surveys assessed primary care settings in the 11 intervention communities. RESULTS: The physicians' survey (response rate, 48%) indicated that physicians report intervention with smokers more than 70% of the time, but the interventions rarely include key behavioral elements necessary for smoking modification. Physicians who received formal training in smoking cessation reported that they believed themselves to be more prepared and that they spent more time counseling patients than physicians who were not trained. The office survey (response rate, 83.2%) indicated that smoke-free policies are in place in most clinics and offices and that many offices provide printed materials on smoking cessation. However, few offices had staff to coordinate smoking cessation activities. These surveys will be repeated following the intervention phase of the Community Intervention Trial for Smoking Cessation to assess changes in counseling practices and office policies. CONCLUSION: There is a positive relationship between attending training and intervening with more cessation activities. Physicians perceive themselves as prepared to help smokers, but few are providing more than advice to stop smoking.


Asunto(s)
Medicina Familiar y Comunitaria , Rol del Médico , Cese del Hábito de Fumar , Consejo , Humanos , Educación del Paciente como Asunto
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