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1.
Chem Commun (Camb) ; 51(73): 13910-3, 2015 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-26239759

RESUMEN

We present a novel approach to remove the structure-directing agent (SDA) from as-synthesized zeolites using an atmospheric pressure plasma jet (APPJ). This reduces the time required to less than 60 seconds as compared to the existing thermal calcination, whose durations range from hours to days. The highly reactive plasma also results in a pronounced Q(3)-to-Q(4) transformation in the pure-silica zeolite MFI.

2.
Rev Sci Instrum ; 80(8): 084702, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19725673

RESUMEN

We present a nuclear radiation detection mechanism using millimeter waves as an alternative to conventional detection. It is based on the concept that nuclear radiation causes ionization of air and that if we place a dielectric material near the radiation source, it acts as a charge accumulator of the air ions. We have found that millimeter waves can interrogate the charge cloud on the dielectric material remotely. This concept was tested with a standoff millimeter wave system by monitoring the charge levels on a cardboard tube placed in an x-ray beam.


Asunto(s)
Monitoreo de Radiación/métodos , Radiación Ionizante , Aire , Algoritmos , Iones , Monitoreo de Radiación/instrumentación , Rayos X
3.
Clin Genet ; 75(4): 334-45, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19419416

RESUMEN

This multicenter study evaluated the mutation spectrum and frequencies of the MLH1 and MSH2 genes and determined the occurrence of large genomic deletions in 93 unrelated Taiwanese families that fulfilled the Amsterdam criteria II by denaturing high-performance liquid chromatography analysis, DNA sequencing for aberrant chromatograms, and multiplex ligation-dependent probe amplification analysis. In total, 38 pathogenic mutations (10 large deletions and 28 point mutations or small deletion/insertions) in the MSH2 or MLH1 gene were identified in 61 of the 93 families (66%). Three of the 10 large deletions and 14 of the 28 point mutations or small insertions/deletions have not been reported elsewhere. Three mutations in the MLH1 gene, the MLH1c.1846_1848delAAG (5 families), deletion exons 11-15 (4 unrelated families), and MLH1c.793C>T (13 unrelated families), accounted for 35% of all cases with pathogenic mutations. Haplotype analysis indicated that mutant c.793C>T alleles were derived from two distinct common founders that might be inherited from a single ancestor of presumably Chinese origin. As a mutation detection strategy for Taiwanese Lynch syndrome patients, we recommend that diagnosis starts with screening for large genomic deletions and continues by screening for common mutations in exons 10 and 16 of the MLH1 gene prior to searching for small mutations in the remaining exons.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Efecto Fundador , Proteína 2 Homóloga a MutS/genética , Proteínas Nucleares/genética , Análisis Mutacional de ADN , Salud de la Familia , Femenino , Frecuencia de los Genes , Mutación de Línea Germinal , Humanos , Masculino , Homólogo 1 de la Proteína MutL , Linaje , Mutación Puntual , Eliminación de Secuencia , Taiwán
4.
Cancer Causes Control ; 9(3): 269-75, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9684707

RESUMEN

OBJECTIVES: The etiology of male breast cancer is obscure, although an excess risk has been associated with Klinefelter syndrome, testicular disorders, benign breast disease including gynecomastia, use of exogenous estrogens, radiation, and a family history of male or female breast cancer. We conducted a case-control study to investigate risk factors further for breast cancer in men. METHODS: Based on data from the 1986 National (United States) Mortality Followback Survey (NMFS) of almost 20,000 deceased adults (age 25 years or over), we compared information obtained from next-of-kin interviews of 178 men who died of breast cancer with that of 512 male controls who died of other causes. Information was obtained on selected demographic and other factors, including diet, exercise, occupation, height and weight, and use of tobacco and alcohol. RESULTS: Increased risks were found for men who were described by their next-of-kin as very overweight (odds ratio [OR] = 2.3, 95 percent confidence interval [CI] = 1.1-5.0). The risks associated with the three upper quartiles of body mass index (BMI) (wt/ht2) were 1.3, 1.6, and 2.3, respectively, with a significant dose-response relationship (P < 0.01). An excess risk was also associated with limited exercise (OR = 1.3, CI = 0.8-2.0). Consumption of red meat was associated with an increased risk, and consumption of fruits and vegetables with a decreased risk, although the trends were not significant. No association was found for tobacco or alcohol use, but an excess risk was associated with higher levels of socioeconomic status (SES) (OR = 1.8, CI = 1.1-3.0). CONCLUSIONS: Our study suggests that obesity increases the risk of male breast cancer, possibly through hormonal mechanisms, while dietary factors, physical activity, and SES indicators also deserve further investigation.


Asunto(s)
Neoplasias de la Mama Masculina/etiología , Dieta , Estilo de Vida , Adolescente , Adulto , Anciano , Neoplasias de la Mama Masculina/epidemiología , Estudios de Casos y Controles , Ejercicio Físico , Humanos , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Factores de Riesgo , Clase Social , Estados Unidos/epidemiología
5.
Int J Cancer ; 77(4): 549-53, 1998 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-9679757

RESUMEN

The association of diet, smoking/drinking and occupation with subsequent risk of fatal colorectal cancer was investigated in a cohort of 17,633 white males aged 35 and older, who completed a mail questionnaire in 1966. During the subsequent 20 years of follow-up, 120 colon cancer and 25 rectal cancer deaths were identified. Due to small numbers, no significant dose-response trends were observed in the study, but risk of colon cancer was elevated among heavy cigarette smokers (> or = 30/day; RR = 2.3, 95% CI 0.9-5.7), heavy beer drinkers (> or = 14 times/month; RR = 1.9, 95% CI 1.0-3.8) and white-collar workers (RR = 1.7, 95% CI 1.0-3.0) or crafts workers within service and trade industries (RR = 2.6, 95% CI 1.1-5.8). In addition, an increased risk was seen for those who consumed red meat more than twice a day (RR = 1.8, 95% CI 0.8-4.4). Risk patterns for cancers of the colon and rectum combined were similar to those reported for cancer of the colon, but the estimates were somewhat dampened. Our findings support previous reports that a high intake of red meat and a sedentary life-style may increase the risk of colon cancer.


Asunto(s)
Neoplasias del Colon/mortalidad , Neoplasias del Recto/mortalidad , Población Blanca/estadística & datos numéricos , Consumo de Bebidas Alcohólicas , Ejercicio Físico , Conducta Alimentaria , Estudios de Seguimiento , Humanos , Masculino , Factores de Riesgo , Fumar/epidemiología , Estados Unidos/epidemiología
6.
Int J Cancer ; 65(4): 432-6, 1996 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-8621222

RESUMEN

Adrenal cancer is a heterogeneous group of neoplasms with unknown etiology. In search of risk factors, we conducted a case-control study based on data from the 1986 National Mortality Followback Survey, which included a questionnaire sent to the next of kin of almost 20,000 deceased adults (age > or = 25 year) in the United States. Information was obtained on a large number of items, including use of cigarettes, alcohol, oral contraceptives (OCs), height and weight and food consumption patterns. A total of 176 subjects who died of adrenal cancer (88 men and 88 women) and 352 controls (176 men and 176 women) who died of causes unrelated to smoking, drinking or OCs (for female controls) were included in the study. Although information on histologic type was not available, most cases were estimated from incidence surveys to be adrenocortical carcinoma, with a small percentage being malignant pheochromocytoma or neuroblastoma. An increased risk was associated with heavy smoking (> or = 25 cigarettes/day) among men (odds ratio [OR] = 2.0, 95% confidence interval [CI] 1.0-4.4) but not women. No clear association was seen for alcohol use, height and weight or food consumption patterns in either sex. Among women, increased risks were found for ever users of OCs (OR = 1.8, 95% CI 1.0-3.2) and especially those who used them before age 25 (OR = 2.5, 95% CI 1.2-5.5). When the analysis was restricted to subjects with spousal respondents, more pronounced risks were seen for ever users of OCs and for those who used OCs before age 25. Our findings suggest that cigarette smoking and use of OCs may increase the risk of adrenal cancer, but additional studies are needed with more detailed information on risk factors and histologic type of adrenal cancer.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/etiología , Anticonceptivos Orales/efectos adversos , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
7.
Am J Epidemiol ; 138(11): 965-72, 1993 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-8256781

RESUMEN

A case-control analysis of cancer of the nasal cavity and sinuses was performed using data from the 1986 National Mortality Followback Survey. Data on cigarette smoking, alcohol consumption, usual diet, and other factors from 147 white men who died from nasal cancer and from 449 controls who died from other causes were compared. Cigarette smoking was related to an increased risk of nasal cancer, with a doubling of risk among heavy or long-term smokers and a reduction in risk among long-term quitters. Among nonsmokers, having a spouse who smoked was associated with a significantly elevated risk of nasal cancer. After adjustment for smoking, a significant dose-response relation was also noted between alcohol drinking and risk of nasal cancer. High consumption of salted/smoked foods was associated with elevated risk, and risk tended to decrease with increasing intake of vegetables. Associations were more pronounced for cigarette smoking and certain dietary items when the analysis was restricted to maxillary sinus cancer. The study confirms that cigarette smoking is a risk factor for nasal cancer, and provides further evidence that dietary factors may play a role in the etiology of this malignancy.


Asunto(s)
Neoplasias Nasales/mortalidad , Neoplasias de los Senos Paranasales/mortalidad , Población Blanca , Anciano , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/epidemiología , Estudios de Casos y Controles , Dieta/efectos adversos , Encuestas Epidemiológicas , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Neoplasias Nasales/etiología , Oportunidad Relativa , Neoplasias de los Senos Paranasales/etiología , Factores de Riesgo , Factores Sexuales , Fumar/efectos adversos , Fumar/epidemiología , Contaminación por Humo de Tabaco/efectos adversos , Estados Unidos/epidemiología , Población Blanca/estadística & datos numéricos
8.
Cancer Causes Control ; 4(5): 477-82, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8218880

RESUMEN

Risk factors for pancreatic cancer were evaluated in a cohort study of 17,633 White men in the United States who responded to a mailed questionnaire in 1966 and were followed-up through 1986 for mortality. Cigarette smoking and alcohol consumption were found to be important risk factors for pancreatic cancer. Risks increased significantly with number of cigarettes smoked, reaching fourfold for smokers of 25 or more cigarettes per day relative to nonsmokers. Alcohol intake also was related significantly to risk, with consumers of 10 or more drinks per month having three times the risk of nondrinkers, but dose-response trends among drinkers were not smooth. Coffee consumption was unrelated to risk. Dietary analyses revealed a rising rate of pancreatic cancer mortality with increasing consumption of meat after adjustment for other risk factors. Men in the highest quartile of meat intake had about three times the risk of those in the lowest quartile. No consistent association, however, was observed for consumption of fruits, vegetables, or grains. This study confirms cigarette smoking as an important risk factor for pancreatic cancer, and provides evidence that elevated intake of alcohol and meat may increase the risk of this fatal malignancy.


Asunto(s)
Consumo de Bebidas Alcohólicas/epidemiología , Conducta Alimentaria , Neoplasias Pancreáticas/epidemiología , Fumar/epidemiología , Adulto , Bebidas Alcohólicas/estadística & datos numéricos , Animales , Cerveza/estadística & datos numéricos , Café , Estudios de Cohortes , Peces , Estudios de Seguimiento , Humanos , Masculino , Carne , Neoplasias Pancreáticas/mortalidad , Plantas Tóxicas , Factores de Riesgo , Tabaco sin Humo , Estados Unidos/epidemiología , Población Blanca
9.
Cancer Causes Control ; 4(2): 163-9, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8481495

RESUMEN

Small intestine cancer is relatively rare. Clinical reports have suggested that several medical conditions may predispose to increased occurrence of this cancer, but otherwise its etiology is unknown. In one of the first case-control studies of this cancer, we compared questionnaire responses provided by next-of-kin of 430 persons who died of small intestine cancer cf921 controls who died of other causes. Subjects were identified from decedents included in the 1986 United States National Mortality Followback Survey. The questionnaires sought information on demographic and lifestyle characteristics, including diet and use of tobacco and alcohol. Tobacco and alcohol consumption were unrelated to risk of small intestine cancer, but weekly or more frequent consumption of red meat and monthly or more frequent intake of salt-cured/smoked foods were associated with two- to three fold increases in risk. The findings suggest that dietary factors probably are involved in risk of small intestine cancer, but additional research in other settings is required to clarify the determinants of these rare cancers.


Asunto(s)
Neoplasias Intestinales/epidemiología , Intestino Delgado/fisiopatología , Adulto , Consumo de Bebidas Alcohólicas/efectos adversos , Estudios de Casos y Controles , Dieta , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Tabaquismo , Estados Unidos/epidemiología
10.
J Natl Cancer Inst ; 84(14): 1118-9, 1992 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-1619686

RESUMEN

PIP: Researchers from the US National Cancer Institute compared data on 25-49 year old US women who died of primary liver cancer between 1985 and 1986 with data on age matched controls who died of causes other than liver conditions or oral contraceptive (OC) related conditions to determine the association between primary liver cancer and parity. Women who had experienced at least 1 live birth wear 1.9 times more likely to have died of primary liver cancer than were nulliparous women. The association was not significant (p=.22), however. The highest risks were among children with at least 6 children (odds ratio [OR]=2.9) and with 2 children (2.1). Further the risks were greater when the parents or spouse completed the questionnaire and the association almost reached significance (p=.07). This may have been due to parents and spouse providing more complete information than a friend or neighbor. The risks of developing primary liver cancer were higher among women who had never used OCs than they were among those who ever did. For example, the OR for never users past parity 2 was 3.6 compared with 1.3 for ever OC users. There was a higher risk associated with parity among long term OC users (=or 5 years) than with short-term OC users, however. The researchers concluded that since parity was positively associated with increased risk of primary liver cancer in the US (a low risk country), endogenous hormones may contribute to liver cancer development. The following facts add to this plausibility. Estrogen profiles of parous women are different from those of nulliparous women. Estrogen levels rise considerably during pregnancy. Estrogens alter liver metabolism. Pregnancy makes the body more defenseless against hepatitis and its sequelae. In low risk countries, the risk of primary liver cancer rises among women using exogenous hormones.^ieng


Asunto(s)
Neoplasias Hepáticas/epidemiología , Paridad , Adulto , Estudios de Casos y Controles , Anticonceptivos Orales/efectos adversos , Femenino , Humanos , Neoplasias Hepáticas/inducido químicamente , Neoplasias Hepáticas/etiología , Persona de Mediana Edad , Factores de Riesgo
11.
Leuk Res ; 16(6-7): 621-4, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1635380

RESUMEN

Among 17,633 U.S. white male insurance policy holders whose use of tobacco was characterized in a 1966 self-administered questionnaire, there were 49 deaths from non-Hodgkin's lymphoma (NHL) and 21 from multiple myeloma (MM) during a 20-year follow-up. Men who had ever smoked cigarettes had an elevated mortality from NHL (RR = 2.1; CI = 0.9-4.9), with risk almost four-fold greater among the heaviest smokers (RR = 3.8; CI = 1.4-10.1) compared with those who used no tobacco. In contrast, risk of MM was only slightly elevated among those who had ever smoked cigarettes (RR = 1.3; CI = 0.4-3.9) and without evidence of a dose-response trend. Since this is the first cohort study suggesting a link between cigarette smoking and NHL and findings from case-control studies have been inconsistent, additional clarification should be sought from larger incidence-based cohort investigations.


Asunto(s)
Linfoma no Hodgkin/epidemiología , Mieloma Múltiple/epidemiología , Fumar/efectos adversos , Adulto , Anciano , Estudios de Cohortes , Estudios de Seguimiento , Humanos , Linfoma no Hodgkin/mortalidad , Masculino , Persona de Mediana Edad , Mieloma Múltiple/mortalidad , Estudios Prospectivos , Factores de Riesgo , Estados Unidos/epidemiología
12.
Cancer Causes Control ; 3(3): 247-54, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1610971

RESUMEN

In 1966, a cohort of White males aged 35 or over, who were policy-holders with the Lutheran Brotherhood Insurance Society (United States), completed a mail questionnaire on tobacco use, diet, and demographic characteristics. During the 20 years of follow-up, 219 lung cancer deaths occurred. Besides the strong relationship with cigarette smoking, we observed an effect on lung cancer risk among current users of cigars or pipes who were nonsmokers of cigarettes (relative risk [RR] = 3.5, 95 percent confidence interval [CI] = 1.0-12.6) or who were past/occasional users of cigarettes (RR = 2.7, CI = 1.4-5.3). In addition, elevated risks (from 1.5 to 2.6) of lung cancer were found among craftsmen and laborers, with the highest risks among subjects who worked in the mining or manufacturing industry. No association between current (as of 1966) use of beer or hard liquor and lung cancer was observed, although past users were at elevated risk. An inverse association between lung cancer and intake of fruits was observed, and risks of lung cancer were lower among persons in the highest dietary intake quintiles of vitamins A and C. Except for oranges, however, none of the inverse associations with fruits or dietary nutrients had statistically significant trends. The findings from this cohort study add to the evidence of an adverse effect of cigar/pipe smoking and possibly protective effect of dietary factors on lung cancer risk.


Asunto(s)
Dieta , Neoplasias Pulmonares/mortalidad , Ocupaciones , Fumar/efectos adversos , Ácido Ascórbico/análisis , Estudios de Seguimiento , Humanos , Seguro de Vida , Neoplasias Pulmonares/epidemiología , Masculino , Encuestas Nutricionales , Factores de Riesgo , Fumar/epidemiología , Encuestas y Cuestionarios , Estados Unidos/epidemiología , Vitamina A/análisis , Población Blanca
13.
Cancer Causes Control ; 3(1): 43-8, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1536912

RESUMEN

The association of oral contraceptive use with liver cancer was examined in a study of 76 deaths from primary liver cancer, 22 deaths from cancer of the intrahepatic bile ducts, and 629 controls among women aged 25 to 49 years. The subjects in the study are from the 1986 National Mortality Followback Survey, which included a questionnaire sent or administered to the next-of-kin of almost 20,000 deceased individuals in the United States. Information on a number of lifestyle factors was collected, including questions on oral contraceptive use. Increased risks of primary liver cancer were found for ever-users (odds ratio [OR] = 1.6, 95 percent confidence interval [CI] = 0.9-2.6), and for long-term (greater than or equal to 10 years) users (OR = 2.0, CI = 0.8-4.8) of oral contraceptives. When the analysis was restricted to subjects whose spouse or parent was the respondent, more pronounced risks were seen for ever-users (OR = 2.7, CI = 1.4-5.3) and long-term users (OR = 4.8, CI = 1.7-14.0). No clear excess risk was found for cancer of the intrahepatic bile ducts. This study, the largest to date, adds to the number of investigations demonstrating an increased risk of primary liver cancer with use, particularly long-term use, of oral contraceptives.


Asunto(s)
Neoplasias de los Conductos Biliares/etiología , Conductos Biliares Intrahepáticos , Anticonceptivos Orales/efectos adversos , Neoplasias Hepáticas/etiología , Adulto , Neoplasias de los Conductos Biliares/epidemiología , Estudios de Casos y Controles , Intervalos de Confianza , Femenino , Encuestas Epidemiológicas , Humanos , Neoplasias Hepáticas/epidemiología , Persona de Mediana Edad , National Center for Health Statistics, U.S. , Oportunidad Relativa , Factores de Riesgo , Estados Unidos
14.
Cancer Causes Control ; 2(6): 413-7, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1764566

RESUMEN

In a 20-year follow-up (1966-86) of 17,633 White males who described tobacco use in a mailed questionnaire sent in 1966, there were 74 deaths from leukemia (including 30 myeloid, 30 lymphatic, and 14 other and unspecified leukemia). Among men who ever smoked cigarettes, increased risks were observed for lymphatic (relative risk [RR] = 2.7), and other and unspecified leukemia (RR = 1.5); risks rose with increasing number of cigarettes smoked, although the dose-response relationship was statistically significant only for total leukemia. Mortality from myeloid leukemia was not elevated, except among those smoking over a pack of cigarettes per day. Results from this cohort support a relationship between cigarette smoking and leukemia. Further studies are needed to elucidate subtype associations with cigarette smoking.


Asunto(s)
Leucemia/etiología , Fumar/efectos adversos , Adulto , Estudios de Cohortes , Humanos , Leucemia/epidemiología , Leucemia Linfoide/epidemiología , Leucemia Linfoide/etiología , Leucemia Mieloide/epidemiología , Leucemia Mieloide/etiología , Masculino , Persona de Mediana Edad , Riesgo , Estados Unidos/epidemiología
15.
Cancer Res ; 50(21): 6836-40, 1990 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-2208150

RESUMEN

A cohort of 17,633 white males age 35 and older responded to a mailed epidemiological questionnaire in 1966 and was followed until 1986 to determine the risk of cancer associated with diet, tobacco use, and other factors. During the 20-year follow-up, 149 fatal prostate cancer cases were identified. Relative risks for prostate cancer were significantly elevated among cigarette smokers (relative risk, 1.8; 95% confidence interval, 1.1-2.9) and users of smokeless tobacco (relative risk, 2.1; 95% confidence interval, 1.1-4.1). No significant associations were found with frequency of consumption of meats, dairy products, fruits, or vegetables. There were no overall significant associations between consumption of vitamin A from animal sources (retinol) and provitamin A from plant sources (carotene) and risk, but positive trends were seen for ages under 75, while inverse associations were found at older ages. Beverage consumption, including drinking coffee and alcohol, was unrelated to risk. Marital status, education, rural/urban status, and farming residence were also unrelated to the risk of fatal prostate cancer. The findings add to limited evidence that tobacco may be a risk factor for prostate cancer, but fail to provide clues to dietary or other risk factors.


Asunto(s)
Dieta/efectos adversos , Neoplasias de la Próstata/epidemiología , Fumar/efectos adversos , Adulto , Anciano , Bebidas Alcohólicas , Carotenoides/farmacología , Café/efectos adversos , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Plantas Tóxicas , Neoplasias de la Próstata/etiología , Neoplasias de la Próstata/mortalidad , Factores de Riesgo , Nicotiana , Vitamina A/farmacología , beta Caroteno
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