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We report high-precision mass measurements of ^{50-55}Sc isotopes performed at the LEBIT facility at NSCL and at the TITAN facility at TRIUMF. Our results provide a substantial reduction of their uncertainties and indicate significant deviations, up to 0.7 MeV, from the previously recommended mass values for ^{53-55}Sc. The results of this work provide an important update to the description of emerging closed-shell phenomena at neutron numbers N=32 and N=34 above proton-magic Z=20. In particular, they finally enable a complete and precise characterization of the trends in ground state binding energies along the N=32 isotone, confirming that the empirical neutron shell gap energies peak at the doubly magic ^{52}Ca. Moreover, our data, combined with other recent measurements, do not support the existence of a closed neutron shell in ^{55}Sc at N=34. The results were compared to predictions from both ab initio and phenomenological nuclear theories, which all had success describing N=32 neutron shell gap energies but were highly disparate in the description of the N=34 isotone.
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BACKGROUND: Imprecise visual estimates of blood loss contribute to morbidity from postpartum hemorrhage. We examined the impact of quantitative assessment of postpartum blood loss on clinical practice and outcomes. METHODS: An observational study comparing blood loss, management and outcomes between two historical cohorts (August 2016 to January 2017 and August 2017 to January 2018) at an academic tertiary care center. Patients in the intervention group (second period) had blood loss quantified compared with visual estimation for controls. RESULTS: We included 7618 deliveries (intervention group n=3807; control group n=3811). There was an increase in the incidence of hemorrhage (blood loss >1â¯L) in the intervention group for both vaginal (2.2% vs 0.5%, Pâ¯<0.001) and cesarean delivery (12.6% vs 6.4%, Pâ¯<0.001). There was also a difference in median blood loss for vaginal (258â¯mL [151-384] vs 300â¯mL [300-350], Pâ¯<0.001); and for cesarean delivery (702â¯mL [501-857] vs 800â¯mL [800-900], Pâ¯<0.001). The median red blood cell units transfused was different in the intervention group having cesarean delivery (2 units [1-2] vs 2 units [2-2], P=0.043). Secondary uterotonic usage was greater in the intervention group for vaginal (22% vs 17.3%, Pâ¯<0.001) but not cesarean delivery (7.0% vs 6.0%, P=0.177). Laboratory costs were different, but not the re-admission rate or length of stay. CONCLUSIONS: Quantifying blood loss may result in increased vigilance for vaginal and cesarean delivery. We identified an association between quantifying blood loss and improved identification of postpartum hemorrhage, patient management steps and cost savings.
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Cesárea/estadística & datos numéricos , Parto Obstétrico/estadística & datos numéricos , Hemorragia Posparto/diagnóstico , Hemorragia Posparto/epidemiología , Adulto , Estudios de Cohortes , Femenino , Humanos , Ciudad de Nueva York , Guías de Práctica Clínica como AsuntoRESUMEN
This corrects the article DOI: 10.1103/PhysRevLett.120.032701.
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We report the mass measurement of ^{56}Cu, using the LEBIT 9.4 T Penning trap mass spectrometer at the National Superconducting Cyclotron Laboratory at Michigan State University. The mass of ^{56}Cu is critical for constraining the reaction rates of the ^{55}Ni(p,γ) ^{56}Cu(p,γ) ^{57}Zn(ß^{+}) ^{57}Cu bypass around the ^{56}Ni waiting point. Previous recommended mass excess values have disagreed by several hundred keV. Our new value, ME=-38626.7(7.1) keV, is a factor of 30 more precise than the extrapolated value suggested in the 2012 atomic mass evaluation [Chin. Phys. C 36, 1603 (2012)CPCHCQ1674-113710.1088/1674-1137/36/12/003], and more than a factor of 12 more precise than values calculated using local mass extrapolations, while agreeing with the newest 2016 atomic mass evaluation value [Chin. Phys. C 41, 030003 (2017)CPCHCQ1674-113710.1088/1674-1137/41/3/030003]. The new experimental average, using our new mass and the value from AME2016, is used to calculate the astrophysical ^{55}Ni(p,γ) and ^{56}Cu(p,γ) forward and reverse rates and perform reaction network calculations of the rp process. These show that the rp-process flow redirects around the ^{56}Ni waiting point through the ^{55}Ni(p,γ) route, allowing it to proceed to higher masses more quickly and resulting in a reduction in ashes around this waiting point and an enhancement to higher-mass ashes.
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BACKGROUND: The impact of combination therapy on disease-related morbidity in patients with established Crohn's disease (CD) or ulcerative colitis (UC) remains to be well-defined. AIM: To examine the effect of combination therapy on disease outcomes in CD and UC. METHODS: Using a multicenter prospective cohort, we classified CD and UC patients as being on monotherapy with anti-TNF or on combination with an immunomodulator. The primary outcome was a composite of new IBD-related surgery, hospitalisations, penetrating complications, need for corticosteroids or new biological at 1 year. Multivariable regression models adjusted for potential confounders. RESULTS: We included 707 patients with CD (45% combination therapy) and 164 with UC (38% combination therapy). Combination therapy was not associated with reduction in the composite outcome in either CD (OR: 0.87, 95% CI: 0.63-1.22) or UC (OR: 1.45, 95% CI: 0.63-3.38). However, while no difference was noted in those with nonstricturing, nonpenetrating CD, a significant reduction in the likelihood of the outcome was seen in those with stricturing or penetrating CD (30% vs 39%, OR: 0.58, 95% CI: 0.37-0.90). A stronger effect was also observed in those with disease duration <5 years (OR: 0.35, 95% CI: 0.14-0.87) compared to those with a longer duration (OR: 0.75, 95% CI: 0.45-1.27). A similar reduction in occurrence of composite outcome was noted with infliximab and with other anti-TNF biologics. CONCLUSION: The benefit of combination immunomodulator-biological therapy is stronger in those with complicated Crohn's disease, particularly early on in their disease course.
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Colitis Ulcerosa/tratamiento farmacológico , Enfermedad de Crohn/tratamiento farmacológico , Fármacos Gastrointestinales/uso terapéutico , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/fisiopatología , Infliximab/uso terapéutico , Adulto , Productos Biológicos , Progresión de la Enfermedad , Quimioterapia Combinada , Femenino , Humanos , Enfermedades Inflamatorias del Intestino/genética , Masculino , Persona de Mediana Edad , Fenotipo , Estudios Prospectivos , Factores de Tiempo , Factor de Necrosis Tumoral alfaRESUMEN
We report the determination of the Q(EC) value of the mirror transition of (11)C by measuring the atomic masses of (11)C and (11)B using Penning trap mass spectrometry. More than an order of magnitude improvement in precision is achieved as compared to the 2012 Atomic Mass Evaluation (Ame2012) [Chin. Phys. C 36, 1603 (2012)]. This leads to a factor of 3 improvement in the calculated Ft value. Using the new value, Q(EC)=1981.690(61) keV, the uncertainty on Ft is no longer dominated by the uncertainty on the Q(EC) value. Based on this measurement, we provide an updated estimate of the Gamow-Teller to Fermi mixing ratio and standard model values of the correlation coefficients.
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We report the first direct measurement of the (14)O superallowed Fermi ß-decay QEC value, the last of the so-called "traditional nine" superallowed Fermi ß decays to be measured with Penning trap mass spectrometry. (14)O, along with the other low-Z superallowed ß emitter, (10)C, is crucial for setting limits on the existence of possible scalar currents. The new ground state QEC value, 5144.364(25) keV, when combined with the energy of the 0(+) daughter state, Ex(0(+))=2312.798(11) keV [F. Ajzenberg-Selove, Nucl. Phys. A523, 1 (1991)], provides a new determination of the superallowed ß-decay QEC value, QEC(sa)=2831.566(28) keV, with an order of magnitude improvement in precision, and a similar improvement to the calculated statistical rate function f. This is used to calculate an improved Ft value of 3073.8(2.8) s.
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The objective of this study was to relate earthworm assemblage structure with three different soil use intensities, and to indentify the physical, chemical, and microbiological soil variables that are associated to the observed differences. Three soil uses were evaluated: 1-Fifty year old naturalized grasslands, low use intensity; 2-Recent agricultural fields, intermediate use intensity, and 3-Fifty year old intensive agricultural fields, high use intensity. Three different sites for each soil use were evaluated from winter 2008 through summer 2011. Nine earthworm species were identified across all sampling sites. The sites shared five species: the native Microscolex dubius, and the introduced Aporrectodea caliginosa, A. rosea, Octalasion cyaneum, and O. lacteum, but they differed in relative abundance by soil use. The results show that the earthworm community structure is linked to and modulated by soil properties. Both species abundance and diversity showed significant differences depending on soil use intensity. A principal component analysis showed that species composition is closely related to the environmental variability. The ratio of native to exotic species was significantly lower in the intensive agricultural system when compared to the other two, lower disturbance systems. Microscolex dubius abundance was related to naturalized grasslands along with soil Ca, pH, mechanical resistance, and microbial respiration. Aporrectodea caliginosa abundance was related to high K levels, low enzymatic activity, slightly low pH, low Ca, and appeared related to the highly disturbed environment. Eukerria stagnalis and Aporrectodea rosea, commonly found in the recent agricultural system, were related to high soil moisture condition, low pH, low Ca and low enzymatic activity. These results show that earthworm assemblages can be good indicators of soil use intensities. In particular, Microscolex dubius, Aporrectodea caliginosa, and Aporrectodea rosea, showed different temporal patterns and species associations, due to the changes in soil properties attributable to soil use intensity, defined as the amount and type of agricultural operations.
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BACKGROUND: Azathioprine (AZA), a pro-drug metabolised to the active metabolites 6-tioguanine nucleotides (6TGN), is a steroid-sparing therapy for Crohn's disease (CD). AIM: To investigate whether AZA therapy is optimised by individualised dosing based on thiopurine methyltransferase (TPMT) activity and 6TGN concentrations. METHODS: This multicentre, double-blind, randomised controlled trial compared the efficacy and safety of weight-based vs. individualised AZA dosing in inducing and maintaining remission in adults and children with steroid-treated CD. The primary outcome was clinical remission (CR) at 16 weeks. In the weight-based arm, subjects received 2.5 mg/kg/day. In the individualised dosing arm, the initial AZA dose was 1.0 mg/kg/day (if intermediate TPMT) or 2.5 mg/kg/day (if normal TPMT). Starting at week 5, the dose was adjusted to target 6TGN concentrations of 250-400 pmol/8 × 10(8) red blood cells (RBC), or to a maximal dose of 4 mg/kg/day. RESULTS: After randomising 50 subjects, the trial was stopped prematurely due to insufficient enrolment. In intention-to-treat analysis, CR rates at week 16 were 40% in the individualised arm vs. 16% in the weight-based arm (P = 0.11). In per-protocol (PP) analysis, week 16 CR rates were 60% in the individualised arm and 25% in the weight-based arm (P = 0.12). At week 16, median 6TGN concentrations in PP remitters and nonremitters were 216 and 149 pmol/8 × 10(8) RBC respectively (P = 0.07). CONCLUSIONS: Despite trends favouring individualised over weight-based AZA dosing, there were no statistically significant differences in efficacy, likely due to low statistical power and inability to achieve the target 6TGN concentrations in the individualised arm. [Clinicaltrials.Gov Identifier Nct00113503].
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Azatioprina/administración & dosificación , Enfermedad de Crohn/tratamiento farmacológico , Inmunosupresores/administración & dosificación , Profármacos/administración & dosificación , Adolescente , Adulto , Azatioprina/efectos adversos , Azatioprina/uso terapéutico , Peso Corporal , Niño , Enfermedad de Crohn/sangre , Método Doble Ciego , Femenino , Humanos , Inmunosupresores/efectos adversos , Inmunosupresores/uso terapéutico , Masculino , Profármacos/efectos adversos , Profármacos/uso terapéutico , Tioguanina/sangre , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: Patients with inflammatory bowel disease (IBD) on certain immunosuppressants have increased herpes zoster (HZ) risk. AIM: To determine the risk of HZ in IBD and how antitumour necrosis factor-alpha (anti-TNF) agents affect this risk. METHODS: We performed a retrospective cohort and nested case-control study using administrative data from IMS LifeLink(®) Information Assets-Health Plan Claims Database. In the cohort, we identified IBD patients Asunto(s)
Herpes Zóster/etiología
, Enfermedades Inflamatorias del Intestino/complicaciones
, Adulto
, Estudios de Casos y Controles
, Estudios de Cohortes
, Femenino
, Humanos
, Inmunosupresores/efectos adversos
, Masculino
, Mercaptopurina/efectos adversos
, Persona de Mediana Edad
, Estudios Retrospectivos
, Factores de Riesgo
, Factor de Necrosis Tumoral alfa/efectos adversos
, Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
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The evaluation of tumour molecular markers may be beneficial in prognosis and predictive in therapy. We develop a stopping rule approach to assist in the efficient utilisation of resources and samples involved in such evaluations. This approach has application in determining whether a specific molecular marker has sufficient variability to yield meaningful results after the evaluation of molecular markers in the first n patients in a study of sample size N (n=N). We evaluated colorectal tumours for mutations (microsatellite instability, K-ras, B-raf, PI3 kinase, and TGFbetaR-II) by PCR and protein markers (Bcl2, cyclin D1, E-cadherin, hMLH1, ki67, MDM2, and P53) by immunohistochemistry. Using this method, we identified and abandoned potentially uninformative molecular markers in favour of more promising candidates. This approach conserves tissue resources, time, and money, and may be applicable to other studies.
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Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/patología , Biomarcadores , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Humanos , Mutación/genética , Pronóstico , Proteínas/genética , Proteínas/metabolismoRESUMEN
An acoustic boundary element model is used to simulate sound propagation in the lung parenchyma and surrounding chest wall. It is validated theoretically and numerically and then compared with experimental studies on lung-chest phantom models that simulate the lung pathology of pneumothorax. Studies quantify the effect of the simulated lung pathology on the resulting acoustic field measured at the phantom chest surface. This work is relevant to the development of advanced auscultatory techniques for lung, vascular, and cardiac sounds within the torso that utilize multiple noninvasive sensors to create acoustic images of the sound generation and transmission to identify certain pathologies.
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Mechanical models of soft tissue are useful for studying vibro-acoustic phenomena. They may be used for validating mathematical models and for testing new equipment and techniques. The objective of this study was to measure density and visco-elastic properties of synthetic materials that can be used to build such models. Samples of nine different materials were tested under dynamic (0.5 Hz) compressive loading conditions. The modulus of elasticity of the materials was varied, whenever possible, by adding a softener during manufacturing. The modulus was measured over a nine month period to quantify the effect of ageing and softener loss on material properties. Results showed that a wide range of the compression elasticity modulus (10 to 1400 kPa) and phase (3.5 degrees -16.7 degrees ) between stress and strain were possible. Some materials tended to exude softener over time, resulting in a weight loss and elastic properties change. While the weight loss under normal conditions was minimal in all materials (<3% over nine months), loss under accelerated weight-loss conditions can reach 59%. In the latter case an elasticity modulus increase of up to 500% was measured. Key advantages and limitations of candidate materials were identified and discussed.
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Fantasmas de Imagen , Radioterapia/métodos , Elastómeros de Silicona/química , Fuerza Compresiva , Elasticidad , Diseño de Equipo , Ensayo de Materiales , Modelos Biológicos , Presión , Estrés Mecánico , Temperatura , Resistencia a la Tracción , Factores de Tiempo , ViscosidadRESUMEN
An acoustic boundary element (BE) model is used to simulate sound propagation in the lung parenchyma. It is computationally validated and then compared with experimental studies on lung phantom models. Parametric studies quantify the effect of different model parameters on the resulting acoustic field within the lung phantoms. The BE model is then coupled with a source localization algorithm to predict the position of an acoustic source within the phantom. Experimental studies validate the BE-based source localization algorithm and show that the same algorithm does not perform as well if the BE simulation is replaced with a free field assumption that neglects reflections and standing wave patterns created within the finite-size lung phantom. The BE model and source localization procedure are then applied to actual lung geometry taken from the National Library of Medicine's Visible Human Project. These numerical studies are in agreement with the studies on simpler geometry in that use of a BE model in place of the free field assumption alters the predicted acoustic field and source localization results. This work is relevant to the development of advanced auscultatory techniques that utilize multiple noninvasive sensors to construct acoustic images of sound generation and transmission to identify pathologies.
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Acústica/instrumentación , Pulmón/anatomía & histología , Modelos Anatómicos , Fantasmas de Imagen , Algoritmos , Simulación por Computador , Elasticidad , Humanos , Masculino , Movimiento (Física) , Porosidad , Reproducibilidad de los Resultados , Sonido , Espectrografía del Sonido , ViscosidadRESUMEN
BACKGROUND: Prior studies suggest that histamines may modulate the development of colorectal neoplasia. AIM: To assess whether histamine receptor antagonist use was associated with adenoma formation. METHODS: Patients (n = 2366) were drawn from three adenoma chemoprevention trials. All underwent baseline colonoscopy with removal of adenoma(s) and were deemed free of remaining lesions; they were followed with surveillance colonoscopy. Medication use was assessed by questionnaire. Adjusted risk ratios for adenoma formation related to histamine receptor antagonist use (histamine H1 and H2 receptor, H1RA and H2RA) were determined using log linear models. RESULTS: In pooled analyses, H1RA exposure was not associated with subsequent adenoma risk (RR = 1.10; 95% CI 0.97-1.25) or multiple adenoma formation (RR = 0.85; 95% CI 0.67-1.07). H2RA use also was not associated with adenoma (RR = 0.90; 95% CI 0.77-1.06), or multiple adenoma (RR = 0.77; 95% CI 0.57-1.04) in the pooled analyses, but H2RA users in the first trial had a decreased risk of adenoma (RR = 0.70; 95% CI 0.48-1.03) and multiple adenoma (RR = 0.31; 95% CI 0.12-0.79). CONCLUSION: H2RA use was associated with reduced risk for adenoma in one trial, but not in the pooled analyses. Further study would be warranted before undertaking randomized trials of H2RAs for adenoma chemoprevention.
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Adenoma/tratamiento farmacológico , Neoplasias Colorrectales/tratamiento farmacológico , Antagonistas de los Receptores Histamínicos H1/uso terapéutico , Antagonistas de los Receptores H2 de la Histamina/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Resultado del TratamientoRESUMEN
Endotracheal tubes (ETTs) are used to establish airway access in patients with ventilatory failure and during general anaesthesia. Tube malpositioning can compromise respiratory function and can be associated with increased morbidity and mortality. Clinical assessment of ETT position normally involves chest auscultation, which is highly skill-dependent and can be misleading. The objective of this pilot study was to investigate breath sound changes associated with ETT malpositioning. Breath sounds were acquired in six human subjects over each hemithorax and over the epigastrium for tracheal, bronchial and oesophageal intubations. When the ETT was in the oesophagus, the acoustic energy ratio between epigastrium and chest surface increased in all subjects (p < 0.04). In addition, ETT placement in the right mainstem bronchus decreased the acoustic energy ratio between the left and right hemithoraxes in all subjects (p < 0.04). A baseline measurement of this energy ratio was needed for bronchial intubation identification. However, using this ratio after bandpass filtering (200-500 Hz) did not require a baseline value, which would increase the utility of this method for initial ETT placement. These results suggest that computerised analysis of breath sounds may be useful for assessment of ETT positioning. More studies are needed to test the feasibility of this approach further.
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Cuerpos Extraños/diagnóstico , Intubación Intratraqueal/efectos adversos , Ruidos Respiratorios/etiología , Acústica , Bronquios , Esófago , Cuerpos Extraños/etiología , Humanos , Proyectos Piloto , Procesamiento de Señales Asistido por ComputadorRESUMEN
Vascular access for renal dialysis is a lifeline for about 120 000 individuals in the United States. Stethoscope auscultation of vascular sounds has some utility in the assessment of access patency, yet can be highly skill-dependent. The objective of the study was to identify acoustic parameters that are related to changes in vascular access patency. The underlying hypothesis is that stenoses of haemodialysis access vessels or grafts cause vascular sound changes that are detectable using computerised data acquisition and analysis. Eleven patients participated in the study. Their vascular sounds were recorded before and after angiography, which was accompanied by angioplasty in most patients. The sounds were acquired using two electronic stethoscopes and then digitised and analysed on a personal computer. Vessel stenosis changes were found to be associated with changes in acoustic amplitude and/or spectral energy distribution. Certain acoustic parameters correlated well (correlation coefficient = 0.98, p < 0.0001) with the change in the degree of stenosis, suggesting that stenosis severity may be predictable from these parameters. Parameters also appeared to be sensitive to modest diameter changes (> 20%), (p < 0.005, Wilcoxon rank sum test). These results suggest that computerised analysis of vascular sounds may be useful in vessel patency surveillance. Further testing using longitudinal studies may be warranted.
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Auscultación/métodos , Oclusión de Injerto Vascular/diagnóstico , Diálisis Renal , Procesamiento de Señales Asistido por Computador , Grado de Desobstrucción Vascular , Derivación Arteriovenosa Quirúrgica , Prótesis Vascular , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Induction of apoptosis has been suggested as a mechanism for the anti-carcinogenic effect of tea constituents in animals and in vitro studies. We addressed this hypothesis in a human study. Study participants were consecutive patients who underwent colonoscopy at the UNC Hospitals (August 1998 to March 2000). Biopsies were taken from normal rectal mucosa. Apoptosis was scored by the terminal deoxyribonucleotide transferase-mediated digoxigenin dUTP nick end labeling (TUNEL) method and by standard morphological criteria. The analysis included 171 patients with adenomas (cases) and 323 adenoma-free controls. After adjusting for sex, age, race, and BMI, apoptotic score was inversely associated with adenoma: the odds ratios (ORs) for linear trend associated with tertiles were 0.3 (0.3-0.5) for morphologic score and 0.5 (0.4-0.6) for the TUNEL score, respectively. Tea consumption (2-3 and >3 versus <2 servings/day) showed a weak negative association with adenoma: the ORs were 0.7 (0.3-1.4) and 0.5 (0.2-1.1), respectively. Neither measurement of apoptotic score changed by the level of tea consumption (P value for Kruskal-Wallis test > or =0.5). We did not find statistical interaction between apoptotic score and tea consumption. Tea exposure is not associated with apoptosis in normal rectal tissue in vivo.
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Adenoma/fisiopatología , Apoptosis , Neoplasias Colorrectales/fisiopatología , Recto/citología , Té , Adenoma/complicaciones , Adenoma/prevención & control , Adulto , Anciano , Biopsia , Colonoscopía , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/prevención & control , Estudios Transversales , Dieta , Femenino , Humanos , Etiquetado Corte-Fin in Situ , Estilo de Vida , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Recto/patologíaRESUMEN
The authors examined the association between colon cancer and meat intake categorized by level of doneness, cooking method, and estimated levels of heterocyclic amines (HCAs), benzo[a]pyrene, and mutagenicity. Data were collected as part of a population-based, case-control study of colon cancer in North Carolina between 1996 and 2000 that included 701 African-American (274 cases, 427 controls) and 957 White (346 cases, 611 controls) participants. Odds ratios were calculated by using unconditional logistic regression, comparing the fifth to the first quintile levels of intake or exposure. Intake of red meat was positively associated with colon cancer (odds ratio (OR) = 2.0, 95% confidence interval (CI): 1.3, 3.2). Associations with meat intake by cooking method were strongest for pan-fried red meat (OR = 2.0, 95% CI: 1.4, 3.0). Associations with meat intake by doneness were strongest for well-/very well done red meat (OR = 1.7, 95% CI: 1.2, 2.5). The strongest association for individual HCAs was reported for 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (DiMeIQx) across all levels of exposure, with odds ratios of 1.8-2.0. Overall, sophisticated exposure measures were used to report modest, positive associations between red meat intake and colon cancer consistent with the hypothesis that HCAs may be among the etiologically relevant compounds in red meat.