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1.
J Nat Prod ; 80(12): 3128-3135, 2017 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-29148767

RESUMEN

The binding properties toward the human telomeric G-quadruplex of the two natural alkaloids coptisine and chelerythrine were studied using spectroscopic techniques, molecular modeling, and X-ray diffraction analysis. The results were compared with reported data for the parent compounds berberine and sanguinarine. Spectroscopic studies showed modest, but different rearrangements of the DNA-ligand complexes, which can be explained considering particular stereochemical features for these alkaloids, in spite of the similarity of their skeletons. In fact, the presence of a dioxolo moiety rather than the two methoxy functions improves the efficiency of coptisine and sanguinarine in comparison to berberine and chelerythrine, and the overall stability trend is sanguinarine > chelerythrine ≈ coptisine > berberine. Accordingly, the X-ray diffraction analysis confirmed the involvement of the benzodioxolo groups in the coptisine/DNA binding by means of π···π, O···π, and CH···O interactions. Similar information is provided by modeling studies, which, additionally, evidenced reasons for the quadruplex vs double-helix selectivity shown by these alkaloids. Thus, the analyses shed light on the key role of the benzodioxolo moieties in strengthening the interaction with the G4-folded human telomeric sequence and indicated the superior G4 stabilizing properties of the benzophenanthridine scaffold with respect to the protoberberine one and conversely the better G4 vs dsDNA selectivity profile of coptisine over the other alkaloids.


Asunto(s)
Alcaloides/química , Benzodioxoles/química , Benzofenantridinas/química , Berberina/análogos & derivados , ADN/química , Berberina/química , Alcaloides de Berberina/química , Cristalografía por Rayos X/métodos , G-Cuádruplex , Humanos , Isoquinolinas/química , Ligandos
2.
Br J Cancer ; 112(3): 446-54, 2015 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-25490523

RESUMEN

BACKGROUND: To our knowledge, no study assessed the association between dietary patterns and nasopharyngeal carcinoma (NPC) in low-incidence areas. METHODS: We examined this association in a hospital-based case-control study carried out in Italy between 1992 and 2008, including 198 incident NPC cases and 594 controls. A posteriori dietary patterns were identified through principal component factor analysis performed on 28 nutrients and minerals derived from a 78-item food-frequency questionnaire. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional multiple logistic regression models on tertiles of factor scores. RESULTS: We identified five dietary patterns named Animal products, Starch-rich, Vitamins and fibre, Animal unsaturated fatty acids (AUFAs), and Vegetable unsaturated fatty acids (VUFAs). The Animal product (OR=2.62, 95% CI=1.67-4.13, for the highest vs lowest score tertile), Starch-rich (OR=2.05, 95% CI=1.27-3.33), and VUFA (OR=1.90, 95% CI=1.22-2.96) patterns were positively associated with NPC. The AUFA pattern showed a positive association of borderline significance, whereas the Vitamins and fibre pattern was nonsignificantly but inversely associated with NPC. CONCLUSIONS: These findings suggest that diets rich in animal products, starch, and fats are positively related to NPC risk in this low-incidence country.


Asunto(s)
Dieta/estadística & datos numéricos , Conducta Alimentaria , Neoplasias Nasofaríngeas/epidemiología , Adolescente , Adulto , Anciano , Carcinoma de Células Escamosas/epidemiología , Estudios de Casos y Controles , Fibras de la Dieta/administración & dosificación , Femenino , Humanos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Verduras , Adulto Joven
3.
Br J Cancer ; 113(1): 182-92, 2015 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-25989276

RESUMEN

BACKGROUND: Evidence for the possible effect of vitamin E on head and neck cancers (HNCs) is limited. METHODS: We used individual-level pooled data from 10 case-control studies (5959 cases and 12 248 controls) participating in the International Head and Neck Cancer Epidemiology (INHANCE) consortium to assess the association between vitamin E intake from natural sources and cancer of the oral cavity/pharynx and larynx. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression models applied to quintile categories of non-alcohol energy-adjusted vitamin E intake. RESULTS: Intake of vitamin E was inversely related to oral/pharyngeal cancer (OR for the fifth vs the first quintile category=0.59, 95% CI: 0.49-0.71; P for trend <0.001) and to laryngeal cancer (OR=0.67, 95% CI: 0.54-0.83, P for trend <0.001). There was, however, appreciable heterogeneity of the estimated effect across studies for oral/pharyngeal cancer. Inverse associations were generally observed for the anatomical subsites of oral and pharyngeal cancer and within covariate strata for both sites. CONCLUSION: Our findings suggest that greater vitamin E intake from foods may lower HNC risk, although we were not able to explain the heterogeneity observed across studies or rule out certain sources of bias.


Asunto(s)
Neoplasias de Cabeza y Cuello/epidemiología , Vitamina E/administración & dosificación , Adulto , Anciano , Femenino , Humanos , Masculino
4.
J Eur Acad Dermatol Venereol ; 28(1): 1-15, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23763635

RESUMEN

BACKGROUND: The number of original articles investigating the efficacy of cosmetic products in cellulite reduction increased rapidly in the last decade; however, to our knowledge, no systematic review and meta-analysis has been performed so far. OBJECTIVE: We conducted a systematic review of in vivo studies on humans adopting the PRISMA guidelines. Moreover, we used a meta-analytic approach to estimate the overall effect of cosmetic creams in cellulite treatment from controlled trials with more than 10 patients per arm, using thigh circumference reduction as the outcome measure. METHODS: Medline and Embase were searched up to August 2012 to identify eligible studies. RESULTS: Twenty-one original studies were included in the present systematic review. All studies were clinical trials, most of them recruited women only and 67% had an intra-patient study design. About half of the active cosmetic creams tested only contained one active ingredient among xanthenes, herbals or retinoids. The other studies tested cosmetic creams with more complex formulations and most of them included xanthenes. A total of seven controlled trials satisfied the inclusion criteria for the meta-analysis. The pooled mean difference of thigh circumference reduction between the treated and the controlled group was -0.46 cm (95% confidence intervals, CI: -0.85, -0.08), with significant heterogeneity between studies (P < 0.001). CONCLUSION: This article provides a systematic evaluation of the scientific evidence of the efficacy of cosmetic products in cellulite reduction and supports a moderate efficacy in thigh circumference reduction.


Asunto(s)
Tejido Adiposo , Cosméticos , Femenino , Humanos
5.
Br J Cancer ; 109(5): 1360-6, 2013 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-23928660

RESUMEN

BACKGROUND: The Mediterranean diet has been shown to have a beneficial role on various neoplasms, but data are scanty on pancreatic cancer. METHODS: We analysed data from two case-control studies conducted in Italy between 1983 and 2008, including 362 and 326 pancreatic cancer cases and 1552 and 652 hospital-controls, respectively. A Mediterranean Diet Score (MDS) summarising major characteristics of the Mediterranean diet was used in the two studies separately and overall. Two further scores of adherence to the Mediterranean diet were applied in the second study only, the Mediterranean Dietary Pattern Adherence Index (MDP) and the Mediterranean Adequacy Index (MAI). RESULTS: Odds ratios (ORs) for increasing levels of the scores (i.e., increasing adherence) were estimated using multiple logistic regression models. Odds ratio for a MDS score ≥6 compared with <3 was 0.57 (95% confidence interval (CI) 0.34-0.95) in the first study, 0.51 (95% CI 0.29-0.92) in the second study, and 0.48 (95% CI 0.35-0.67) overall. A trend of decreasing risk was observed also for the MDP and MAI the ORs for the highest vs the lowest quintile being 0.44 (95% CI 0.27-0.73) for MDP and 0.68 (95% CI 0.42-1.11) for the MAI. The results were consistent across strata of age, sex, education, body mass index, alcohol drinking, tobacco smoking, and diabetes. CONCLUSION: Our study provides evidence that a priori-defined scores measuring adherence to the Mediterranean diet are favourably associated with pancreatic cancer risk.


Asunto(s)
Dieta Mediterránea , Neoplasias Pancreáticas/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Conducta Alimentaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Factores de Riesgo , Adulto Joven
6.
Br J Cancer ; 109(7): 1914-20, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23922105

RESUMEN

BACKGROUND: Because of their antioxidant and antimutagenic properties, flavonoids may reduce cancer risk. Some flavonoids have antiestrogenic effects that can inhibit the growth and proliferation of endometrial cancer cells. METHODS: In order to examine the relation between dietary flavonoids and endometrial cancer, we analysed data from an Italian case-control study including 454 incident, histologically confirmed endometrial cancers and 908 hospital-based controls. Information was collected through a validated food-frequency questionnaire. We applied data on food and beverage composition to estimate the intake of flavanols, flavanones, flavonols, anthocyanidins, flavones, isoflavones, and proanthocyanidins. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated from multiple logistic regression models conditioned on age and study centre and adjusted for major confounding factors. RESULTS: Women in the highest quartile category of proanthocyanidins with ≥3 mers vs the first three quartile categories had an OR for endometrial cancer of 0.66 (95% CI=0.48-0.89). For no other class of flavonoids, a significant overall association was found. There was a suggestion of an inverse association for flavanones and isoflavones among women with body mass index <25 kg m(-2), and, for flavanones, among parous or non-users of hormone-replacement therapy women. CONCLUSION: High consumption of selected proanthocyanidins may reduce endometrial cancer risk.


Asunto(s)
Neoplasias Endometriales/prevención & control , Conducta Alimentaria , Proantocianidinas/administración & dosificación , Adolescente , Adulto , Anciano , Antocianinas/administración & dosificación , Estudios de Casos y Controles , Femenino , Flavanonas/administración & dosificación , Flavonas/administración & dosificación , Flavonoles/administración & dosificación , Humanos , Isoflavonas/administración & dosificación , Italia , Persona de Mediana Edad , Factores de Riesgo , Encuestas y Cuestionarios , Adulto Joven
7.
Ann Oncol ; 24(6): 1450-8, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23524862

RESUMEN

BACKGROUND: Declines in gastric cancer (GC) incidence and mortality have been related to improvements in diet. It is therefore important to consider dietary patterns. DESIGN: We conducted a systematic review and meta-analysis of the literature through Medline and Embase databases. RESULTS: We identified 16 papers, of these 9 derived dietary patterns through an a posteriori method, 5 through a priori scores, and 2 used both approaches. Eight studies that used the a posteriori approach were considered for the meta-analysis. A favorable role on GC emerged for the 'Prudent/healthy', with an odds ratio (OR) of 0.75 [95% confidence interval (CI): 0.63-0.90], for the highest versus the lowest category. Similar results emerged for separate anatomical subtypes. An unfavorable role on GC emerged for the 'Western/unhealthy' dietary pattern, with an OR of 1.51 (95% CI: 1.21-1.89). This association was weaker for the distal/NOS (not otherwise specified) category (OR = 1.36) compared with the cardia GC (OR = 2.05). Among the a priori scores, the ORs ranged from 0.2 to 0.7 for the favorable and from 1.8 to 6.9 for the unfavorable ones. CONCLUSION: There is a ~2-fold difference in GC risk between a 'Prudent/healthy' diet-rich in fruits and vegetables, and a 'Western/unhealthy' diet-rich in starchy foods, meat and fats.


Asunto(s)
Conducta Alimentaria , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/prevención & control , Grasas de la Dieta/efectos adversos , Sacarosa en la Dieta/efectos adversos , Frutas , Humanos , Carne/efectos adversos , Factores de Riesgo , Neoplasias Gástricas/diagnóstico , Verduras
8.
Ann Oncol ; 24(10): 2651-2656, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23884440

RESUMEN

BACKGROUND: The risk of many cancers is higher in subjects with a family history (FH) of cancer at a concordant site. However, few studies investigated FH of cancer at discordant sites. PATIENTS AND METHODS: This study is based on a network of Italian and Swiss case-control studies on 13 cancer sites conducted between 1991 and 2009, and including more than 12 000 cases and 11 000 controls. We collected information on history of any cancer in first degree relatives, and age at diagnosis. Odds ratios (ORs) for FH were calculated by multiple logistic regression models, adjusted for major confounding factors. RESULTS: All sites showed an excess risk in relation to FH of cancer at the same site. Increased risks were also found for oral and pharyngeal cancer and FH of laryngeal cancer (OR = 3.3), esophageal cancer and FH of oral and pharyngeal cancer (OR = 4.1), breast cancer and FH of colorectal cancer (OR = 1.5) and of hemolymphopoietic cancers (OR = 1.7), ovarian cancer and FH of breast cancer (OR = 2.3), and prostate cancer and FH of bladder cancer (OR = 3.4). For most cancer sites, the association with FH was stronger when the proband was affected at age <60 years. CONCLUSIONS: Our results point to several potential cancer syndromes that appear among close relatives and may indicate the presence of genetic factors influencing multiple cancer sites.


Asunto(s)
Salud de la Familia , Neoplasias/epidemiología , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Humanos , Italia/epidemiología , Masculino , Neoplasias/genética , Riesgo , Factores de Riesgo , Encuestas y Cuestionarios , Suiza/epidemiología
9.
Ann Oncol ; 23(2): 311-8, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21746805

RESUMEN

BACKGROUND: Since when in 1981 a case-control study showed a positive association between coffee and pancreatic cancer, several studies reported inconsistent results on this issue. MATERIALS AND METHODS: We conducted a systematic bibliography search updated March 2011 to identify observational studies providing quantitative estimates for pancreatic cancer risk in relation to coffee consumption. We used a meta-analytic approach to estimate overall relative risk (RR) and 95% confidence interval (CI) for the highest versus the lowest coffee consumption categories, using random-effects models. RESULTS: Based on 37 case-control and 17 cohort studies (10,594 cases), the pooled RR for the highest versus lowest intake was 1.13 (95% CI 0.99-1.29). Considering only the smoking-adjusting studies, the pooled RRs were 1.10 (95% CI 0.92-1.31) for the 22 case-control, 1.04 (95% CI 0.80-1.36) for the 15 cohort, and 1.08 (95% CI 0.94-1.25) for all studies. The pooled RR for the increment of one cup of coffee per day was 1.03 (95% CI 0.99-1.06) for the 28 smoking-adjusting studies reporting three or more coffee consumption categories. No significant heterogeneity was observed across strata of study design, sex, geographic region, and other selected characteristics. CONCLUSIONS: This meta-analysis provides quantitative evidence that coffee consumption is not appreciably related to pancreatic cancer risk, even at high intakes.


Asunto(s)
Café/efectos adversos , Neoplasias Pancreáticas/etiología , Estudios de Casos y Controles , Estudios de Cohortes , Humanos , Riesgo , Factores de Riesgo
10.
Ann Oncol ; 23(12): 3024-3039, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22967993

RESUMEN

BACKGROUND: The relationship between diet and cancers of the upper aerodigestive tract (UADT) has been investigated through dietary patterns. DESIGN: Published studies on the relationship between a priori and a posteriori dietary patterns and UADT cancers were selected through a Medline search. RESULTS: Twenty-four case-control studies were identified. Most of them identified a posteriori dietary patterns, mainly using principal component factor analysis, and a few used a priori dietary patterns, based on the available evidence on known effects of dietary habits on UADT cancers. In one study, no association was found between the identified patterns and UADT cancers. All the remaining 23 papers reported at least one favorable or unfavorable dietary pattern related to UADT cancers. The most consistent findings are the beneficial role of a dietary pattern based on fruit and vegetables or nutrients mostly contained in such foods, and the unfavorable role of an alcohol drinker pattern. A possible unfavorable role of patterns based on meats and animal products emerged as well. CONCLUSION: The consistency of results among populations indicates that diets rich in fruit and vegetables, and poor in alcohol and animal products are favorable for UADT cancers.


Asunto(s)
Neoplasias Esofágicas/epidemiología , Conducta Alimentaria , Neoplasias Laríngeas/epidemiología , Neoplasias de la Boca/epidemiología , Neoplasias Faríngeas/epidemiología , Consumo de Bebidas Alcohólicas , Estudios de Casos y Controles , Frutas , Humanos , Análisis de Componente Principal , Riesgo , Factores de Riesgo , Encuestas y Cuestionarios , Verduras
11.
Ann Oncol ; 23(3): 765-770, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21653682

RESUMEN

BACKGROUND: The role of dietary habits on esophageal cancer risk has been rarely considered in terms of dietary patterns. PATIENTS AND METHODS: We analyzed data from an Italian case-control study, including 304 cases with squamous cell carcinoma of the esophagus and 743 hospital controls. Dietary habits were evaluated using a food frequency questionnaire. A posteriori dietary patterns were identified through principal component factor analysis performed on 28 selected nutrients. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained from multiple logistic regression models applied on quartiles of factor scores, adjusting for potential confounding variables. RESULTS: We identified five major dietary patterns, named 'animal products and related components', 'vitamins and fiber', 'starch-rich', 'other polyunsaturated fatty acids and vitamin D', and 'other fats'. The 'animal products and related components' pattern was positively related to esophageal cancer (OR = 1.64, 95% CI:1.06-2.55, for the highest versus the lowest quartile of factor scores category). The 'vitamins and fiber' (OR = 0.50, 95% CI: 0.32-0.78) and the 'other polyunsaturated fatty acids and vitamin D' (OR = 0.48, 95% CI: 0.31-0.74) were inversely related to esophageal cancer. No significant association was observed for the other patterns. CONCLUSION: Our findings suggest that a diet rich in foods from animal origin and poor in foods containing vitamins and fiber increase esophageal cancer risk.


Asunto(s)
Carcinoma de Células Escamosas/etiología , Dieta/efectos adversos , Neoplasias Esofágicas/etiología , Adulto , Anciano , Carcinoma de Células Escamosas/epidemiología , Estudios de Casos y Controles , Neoplasias Esofágicas/epidemiología , Femenino , Humanos , Italia , Masculino , Persona de Mediana Edad , Análisis de Componente Principal , Factores de Riesgo , Encuestas y Cuestionarios
12.
Br J Cancer ; 104(7): 1207-13, 2011 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-21386846

RESUMEN

BACKGROUND: Endometrial cancer is strongly associated with body mass index (BMI), but the influence of BMI history and of different types of obesity is uncertain. METHODS: A case-control study was carried out in Italy including 454 cases and 908 controls admitted to hospital for acute non-hormone-related conditions. Odds ratios (ORs) and 95% confidence intervals (CIs) were computed using multivariate logistic and spline regression models. RESULTS: The OR for BMI >30 at diagnosis compared with 20 to <25 kg m(-2) was 4.08 (95% CI: 2.90-5.74). The association for BMI was monotonic with a possible steeper increase for BMI above 28. Conversely, waist-to-hip ratio (WHR) showed a bell shaped curve with increased OR (2.10; 95% CI: 1.43-3.09) in the intermediate tertile only. After stratification by BMI at diagnosis, history of weight loss and BMI at age 30 did not influence endometrial cancer risk. History of obesity in middle age had a weak and not significant adverse effect among obese women (OR=1.60; 95% CI: 0.52-4.96). CONCLUSION: The predominant importance of recent weight compared to lifetime history, justifies encouraging weight reduction in women at any age.


Asunto(s)
Índice de Masa Corporal , Neoplasias Endometriales/etiología , Adulto , Factores de Edad , Anciano , Estatura , Peso Corporal , Estudios de Casos y Controles , Femenino , Humanos , Italia , Modelos Logísticos , Persona de Mediana Edad , Oportunidad Relativa , Riesgo , Relación Cintura-Cadera
13.
Ann Oncol ; 20(3): 581-90, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18842615

RESUMEN

BACKGROUND: Limited information is available on the relationship between dietary patterns and breast and ovarian cancers. PATIENTS AND METHODS: Cases were 2569 breast cancers and 1031 ovarian cancers hospitalized in four Italian areas from 1991 to 1999. Controls were 3413 women in hospital for acute non-neoplastic diseases. Dietary habits were investigated through a validated food-frequency questionnaire. Dietary patterns were obtained from a K-means clustering on factor scores from factor analysis. Odds ratios (ORs) for both cancers were estimated using unconditional multiple logistic regression models on clusters of patients. Floating absolute risk method was used for reporting 95% floating confidence intervals (FCIs). RESULTS: We identified five groups of subjects. The G3 cluster, including subjects with the lowest intakes of any food group, was used as reference. The G5 cluster, including subjects mainly consuming bread and pasta, was unfavorable for both cancers (OR=1.23, 95% FCI=1.08-1.38 for breast cancer, OR=1.21, 95% FCI=1.03-1.42 for ovarian cancer). The G1 group, including subjects mainly consuming fruits and vegetables, was protective against ovarian cancer (OR=0.81, 95% FCI=0.67-0.98). CONCLUSIONS: A diet mainly based on bread and pasta is unfavorable for breast and ovarian cancers; a diet rich in fruits and vegetables may be associated with a reduced risk of ovarian cancer.


Asunto(s)
Neoplasias de la Mama/epidemiología , Dieta , Neoplasias Ováricas/epidemiología , Estudios de Casos y Controles , Femenino , Humanos , Italia/epidemiología , Factores de Riesgo , Encuestas y Cuestionarios
14.
Ann Oncol ; 19(2): 380-3, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17951595

RESUMEN

BACKGROUND: Risk of thyroid cancer has already been related to refined cereals and starch food, but the association has not been studied in terms of glycemic index (GI) and glycemic load (GL). PATIENTS AND METHODS: We analyzed data from a case-control study conducted in Italy from 1986 to 1992 and including 399 histologically confirmed and incident cases of thyroid cancer and 616 control subjects. Information on dietary habits was derived through a food-frequency questionnaire and multivariate odds ratios (ORs) for GI and GL levels were estimated with adjustment for age, education, sex, area of residence, history of diabetes, body mass index, smoking, alcohol consumption, intake of fruit and vegetables, and noncarbohydrate energy intake. RESULTS: Compared with the lowest tertile, the ORs in subsequent tertiles were 1.68 and 1.73 for GI, and 1.76 and 2.17 for GL. The OR for highest tertile of GI compared with lowest one was 1.70 for papillary and 1.57 for follicular thyroid cancer. The ORs for GL were 2.17 for papillary and 3.33 for follicular thyroid cancer. CONCLUSION: Our study shows that high dietary levels of GI and GL are associated with thyroid cancer risk.


Asunto(s)
Glucemia/análisis , Carbohidratos de la Dieta/efectos adversos , Índice Glucémico , Neoplasias de la Tiroides/epidemiología , Neoplasias de la Tiroides/etiología , Adenocarcinoma Folicular/epidemiología , Adenocarcinoma Folicular/etiología , Adenocarcinoma Folicular/patología , Adolescente , Adulto , Distribución por Edad , Anciano , Biopsia con Aguja , Índice de Masa Corporal , Carcinoma Papilar/epidemiología , Carcinoma Papilar/etiología , Carcinoma Papilar/patología , Estudios de Casos y Controles , Femenino , Humanos , Inmunohistoquímica , Incidencia , Italia/epidemiología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Oportunidad Relativa , Pronóstico , Valores de Referencia , Estudios Retrospectivos , Factores de Riesgo , Distribución por Sexo , Neoplasias de la Tiroides/patología
15.
J Appl Microbiol ; 105(6): 2065-75, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19120652

RESUMEN

AIMS: To isolate and characterize the laccase isoforms from S. ochraceum 1833 - a new active producer of high extracellular laccase activity. METHODS AND RESULTS: Three laccase isoforms (laccases I, II and III) with 57.5, 59.5 and 63 kDa molecular masses respectively were purified from S. ochraceum 1833 and in contrast to the known laccases had strongly pronounced absorption at 611 nm with molar extinction coefficients ranging from 7170 to 7830 mol(-1) l cm(-1). All isoforms showed maximal activity with ABTS at low pH (

Asunto(s)
Basidiomycota/enzimología , Lacasa/química , Secuencia de Aminoácidos , Basidiomycota/crecimiento & desarrollo , Concentración de Iones de Hidrógeno , Cinética , Lacasa/metabolismo , Isoformas de Proteínas , Espectrofotometría , Temperatura
16.
Artículo en Inglés | MEDLINE | ID: mdl-16754979

RESUMEN

Salicylate 1,2-dioxygenase, a new ring-fission dioxygenase from the naphthalenesulfonate-degrading strain Pseudaminobacter salicylatoxidans which oxidizes salicylate to 2-oxohepta-3,5-dienedioic acid by a novel ring-fission mechanism, has been crystallized. Diffraction-quality crystals of salicylate 1,2-dioxygenase were obtained using the sitting-drop vapour-diffusion method at 277 K from a solution containing 10%(w/v) ethanol, 6%(w/v) PEG 400, 0.1 M sodium acetate pH 4.6. Crystals belong to the primitive tetragonal space group P4(3)2(1)2 or P4(1)2(1)2, with unit-cell parameters a = 133.3, c = 191.51 A. A complete data set at 100 K extending to a maximum resolution of 2.9 A was collected at a wavelength of 0.8423 A. Molecular replacement using the coordinates of known extradiol dioxygenases structures as a model has so far failed to provide a solution for salicylate 1,2-dioxygenase. Attempts are currently being made to solve the structure of the enzyme by MAD experiments using the anomalous signal of the catalytic Fe(II) ions. The salicylate 1,2-dioxygenase structural model will assist in the elucidation of the catalytic mechanism of this ring-fission dioxygenase from P. salicylatoxidans, which differs markedly from the known gentisate 1,2-dioxygenases or 1-hydroxy-2-naphthoate dioxygenases because of its unique ability to oxidatively cleave salicylate, gentisate and 1-hydroxy-2-naphthoate with high catalytic efficiency.


Asunto(s)
Bacterias Aerobias/enzimología , Dioxigenasas/química , Proteínas Bacterianas/química , Cristalización/métodos , Hierro , Difracción de Rayos X
17.
Cancer Res ; 49(4): 1049-51, 1989 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-2912550

RESUMEN

The relationship between coffee drinking and the risk of digestive tract neoplasms was analyzed in a case-control study of 50 cases of cancer of the mouth or pharynx, 209 of the esophagus, 397 of the stomach, 455 of the colon, 295 of the rectum, 151 of the liver, 214 of the pancreas, and 1944 control subjects admitted for acute, non-digestive tract disorders. There was no significant or consistent association between coffee and cancers of the mouth or pharynx, esophagus, stomach, liver, or pancreas. In particular, for pancreatic cancer, the multivariate relative risks for the intermediate and upper tertiles were 1.05 and 1.01, respectively. There were significant inverse trends in risk with measures of coffee consumption for colon and rectal cancers, the multivariate relative risks according to tertiles of coffee consumption being 0.86 and 0.64 for colon and 0.97 and 0.66 for rectum. This apparent protection is in agreement with some (but not all) previous epidemiological evidence and finds a possible biological interpretation in terms of interference on bile secretion, causing reduced bile acid and neutral sterol concentrations in the bowel. In conclusion, the results of this study, the major interest of which lies in the opportunity of drawing up an overall pattern of risk for various digestive neoplasms, offer further reassurance as regards the effects of coffee on digestive tract carcinogenesis.


Asunto(s)
Café/efectos adversos , Neoplasias del Sistema Digestivo/etiología , Adulto , Anciano , Femenino , Humanos , Italia , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores Socioeconómicos
18.
J Mol Biol ; 288(3): 413-26, 1999 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-10329151

RESUMEN

The crystal structure of the engineered monomeric human Cu,ZnSOD triple mutant F50E/G51E/E133Q (Q133M2SOD) is reported at atomic resolution (1.02 A). This derivative has about 20 % of the wild-type activity. Crystals of Q133M2SOD have been obtained in the presence of CdCl2. The metal binding site is disordered, with both cadmium and copper ions simultaneously binding to the copper site. The cadmium (II) ions occupy about 45 % of the copper sites by binding the four histidine residues which ligate copper in the native enzyme, and two further water molecules to complete octahedral coordination. The copper ion is tri-coordinate, and the fourth histidine (His63) is detached from copper and bridges cadmium and zinc. X-ray absorption spectroscopy performed on the crystals suggests that the copper ion has undergone partial photoreduction upon exposure to the synchrotron light. The structure is also disordered in the disulfide bridge region of loop IV that is located at the subunit/subunit interface in the native SOD dimer. As a consequence, the catalytically relevant Arg143 residue is disordered. The present structure has been compared to other X-ray structures on various isoenzymes and to the solution structure of the same monomeric form. The structural results suggest that the low activity of monomeric SOD is due to the disorder in the conformation of the side-chain of Arg143 as well as of loop IV. It is proposed that the subunit-subunit interactions in the multimeric forms of the enzyme are needed to stabilize the correct geometry of the cavity and the optimal orientation of the charged residues in the active channel. Furthermore, the different coordination of cadmium and copper ions, contemporaneously present in the same site, are taken as models for the oxidized and reduced copper species, respectively. These properties of the structure have allowed us to revisit the enzymatic mechanism.


Asunto(s)
Superóxido Dismutasa/química , Sitios de Unión , Cadmio/metabolismo , Catálisis , Cobre/metabolismo , Cristalografía por Rayos X , Humanos , Modelos Moleculares , Mutagénesis , Conformación Proteica , Espectrometría por Rayos X , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo
19.
Eur J Cancer Prev ; 14(2): 139-42, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15785317

RESUMEN

Resveratrol is a non-flavonoid polyphenol that has attracted attention as a potential anticancer agent in vitro and in vivo, but scanty epidemiological data are available. We have therefore analysed the relation between dietary intake of resveratrol and breast cancer risk using data from a case-control study conducted between 1993 and 2003 in the Swiss Canton of Vaud on 369 cases and 602 controls. Compared with the lowest tertile of total resveratrol intake, the multivariate odds ratios (OR) were 0.50 for the intermediate and 0.39 for the highest tertile, and the trend in risk was significant. A significant inverse association was observed for resveratrol from grapes (OR = 0.64 and 0.55), but not for wine. The inverse relation between resveratrol and breast cancer risk was not explained by several potential confounding factors, including detailed allowance for alcohol intake, nor attributable to a non-specific favourable effect of fruit on breast cancer risk.


Asunto(s)
Anticarcinógenos/farmacología , Neoplasias de la Mama/prevención & control , Estilbenos/farmacología , Vino , Adulto , Neoplasias de la Mama/epidemiología , Estudios de Casos y Controles , Dieta , Femenino , Frutas , Humanos , Incidencia , Persona de Mediana Edad , Oportunidad Relativa , Resveratrol , Factores de Riesgo , Suiza/epidemiología
20.
Cancer Epidemiol Biomarkers Prev ; 6(2): 137-40, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9037565

RESUMEN

Until now, it has been unclear whether there are differences in various risk factor profiles for familial gastric cancer, i.e., gastric cancer among subjects with a family history of the disease. A total of 722 gastric cancer patients and 2024 controls were admitted between 1985 and 1992 to a network of hospitals in the Greater Milan area. Of these, 88 cases and 103 controls who reported a family history of gastric cancer in first degree relatives were considered in the present analysis. There was no relationship between gastric cancer risk and tobacco smoking or alcohol drinking. Shorter duration of electrical refrigerator use was related to a nonsignificant increased risk and a high daily meal frequency was associated with an increased gastric cancer risk. Significant direct trends of risk were observed for pasta (odds ratio, OR = 4.20 for the highest versus the lowest tertile), bread (OR, 2.86), red meat (OR, 3.38), and preserved meat (OR, 1.90). Inverse associations were observed for increasing consumption of selected vegetables and fruits, chiefly peppers (OR = 0.31), total fruits (OR, 0.47), and citrus fruits (OR, 0.38). With reference to selected micronutrients, a significant inverse trend in risk with increasing consumption for beta-carotene (OR, 0.27) and ascorbic acid (OR, 0.20) was observed. These results suggest that dietary risk factors for subjects with a family history of gastric cancer in first-degree relatives are not appreciably different from well-established risk factors of the disease in the general population.


Asunto(s)
Neoplasias Gástricas/genética , Estudios de Casos y Controles , Dieta , Humanos , Italia/epidemiología , Funciones de Verosimilitud , Modelos Logísticos , Factores de Riesgo , Neoplasias Gástricas/epidemiología
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