Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 110
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Antimicrob Agents Chemother ; 58(10): 5848-54, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25049259

RESUMEN

Toxoplasmosis and amebiasis are important public health concerns worldwide. The drugs currently available to control these diseases have proven limitations. Therefore, innovative approaches should be adopted to identify and develop new leads from novel scaffolds exhibiting novel modes of action. In this paper, we describe results from the screening of compounds in the Medicines for Malaria Venture (MMV) open access Malaria Box in a search for new anti-Toxoplasma and anti-Entamoeba agents. Standard in vitro phenotypic screening procedures were adopted to assess their biological activities. Seven anti-Toxoplasma compounds with a 50% inhibitory concentration (IC50) of <5 µM and selectivity indexes (SI) of >6 were identified. The most interesting compound was MMV007791, a piperazine acetamide, which has an IC50 of 0.19 µM and a selectivity index of >157. Also, we identified two compounds, MMV666600 and MMV006861, with modest activities against Entamoeba histolytica, with IC50s of 10.66 µM and 15.58 µM, respectively. The anti-Toxoplasma compounds identified in this study belong to scaffold types different from those of currently used drugs, underscoring their novelty and potential as starting points for the development of new antitoxoplasmosis drugs with novel modes of action.


Asunto(s)
Antiprotozoarios/farmacología , Entamoeba histolytica/efectos de los fármacos , Toxoplasma/efectos de los fármacos , Pruebas de Sensibilidad Parasitaria , Piperazina , Piperazinas/farmacología
2.
J Hum Nutr Diet ; 27(5): 413-25, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24112099

RESUMEN

BACKGROUND: There has been little research published on the adaptation of diabetic exchange list diet approaches for the design of intervention diets in health research despite their clinical utility. The exchange list approach can provide clear and precise guidance on multiple dietary changes simultaneously. The present study aimed to develop exchange list diets for Mediterranean and Healthy Eating, and to evaluate adherence, dietary intakes and markers of health risks with each counselling approach in 120 subjects at increased risk for developing colon cancer. METHODS: A randomised clinical trial was implemented in the USA involving telephone counselling. The Mediterranean diet had 10 dietary goals targeting increases in mono-unsaturated fats, n-3 fats, whole grains and the amount and variety of fruits and vegetables. The Healthy Eating diet had five dietary goals that were based on the US Healthy People 2010 recommendations. RESULTS: Dietary compliance was similar in both diet arms, with 82-88% of goals being met at 6 months, although subjects took more time to achieve the Mediterranean goals than the Healthy Eating goals. The relatively modest fruit and vegetable goals in the Healthy Eating arm were exceeded, resulting in fruit and vegetable intakes of approximately eight servings per day in each arm after 6 months. A significant (P < 0.05) weight loss and a decrease in serum C-reactive protein concentrations were observed in the overweight/obese subgroup of subjects in the Mediterranean arm in the absence of weight loss goals. CONCLUSIONS: Counselling for the Mediterranean diet may be useful for both improving diet quality and for achieving a modest weight loss in overweight or obese individuals.


Asunto(s)
Neoplasias del Colon/prevención & control , Dieta Mediterránea , Dieta Reductora , Alimentos/clasificación , Obesidad/dietoterapia , Sobrepeso/dietoterapia , Educación del Paciente como Asunto , Biomarcadores/sangre , Índice de Masa Corporal , Proteína C-Reactiva/análisis , Neoplasias del Colon/epidemiología , Neoplasias del Colon/etiología , Dieta para Diabéticos , Femenino , Promoción de la Salud , Programas Gente Sana , Humanos , Masculino , Michigan/epidemiología , Persona de Mediana Edad , Obesidad/sangre , Obesidad/fisiopatología , Sobrepeso/sangre , Sobrepeso/fisiopatología , Cooperación del Paciente , Riesgo , Teléfono , Pérdida de Peso
3.
Front Pharmacol ; 12: 648203, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33967785

RESUMEN

Cystic fibrosis (CF) is a rare genetic disease that affects several organs, but lung disease is the major cause of morbidity and mortality. The gene responsible for CF, the CFTR (Cystic Fibrosis Transmembrane Conductance Regulator) gene, has been discovered in 1989. Since then, gene therapy i.e., defective gene replacement by a functional one, remained the ultimate goal but unfortunately, it has not yet been achieved. However, patients care and symptomatic treatments considerably increased CF patients' life expectancy ranging from 5 years old in the 1960s to 40 today. In the last decade, research works on CFTR protein structure and activity led to the development of new drugs which, by readdressing CFTR to the plasma membrane (correctors) or by enhancing its transport activity (potentiators), allow, alone or in combination, an improvement of CF patients' lung function and quality of life. While expected, it is not yet known whether taking these drugs from an early age and for years will improve the quality of life of CF patients in the long term and further increase their life expectancy. Besides, these molecules are not available (specific variants of CFTR) or accessible (national health policies) for all patients and there is still no curative treatment. Another alternative that could benefit from new technologies, such as gene therapy, is therefore still attractive, although it is not yet offered to patients. Faced with the development of new CFTR correctors and potentiators, the question arises as to whether there is still a place for gene therapy and this is discussed in this perspective.

4.
Rev Mal Respir ; 37(3): 218-221, 2020 Mar.
Artículo en Francés | MEDLINE | ID: mdl-32146055

RESUMEN

Although cystic fibrosis is a monogenic disease, a considerable clinical phenotypic variability is observed in patients with the same CFTR mutations. Thanks to the development of new and powerful tools for carrying out genetic studies, several genes called "modifier genes" have been identified as being associated with the severity of the lung function disorder in cystic fibrosis patients. Among these genes, SLC6A14 may modulate the anti-infective response and epithelial integrity of the airways, thus providing a potential therapeutic target to improve the patient's lung function.


Asunto(s)
Sistemas de Transporte de Aminoácidos/genética , Fibrosis Quística/genética , Genes Modificadores , Sistemas de Transporte de Aminoácidos/fisiología , Animales , Fibrosis Quística/patología , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Epistasis Genética/fisiología , Genotipo , Humanos , Mutación
5.
Radiat Prot Dosimetry ; 127(1-4): 120-4, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17562647

RESUMEN

The aim of this study is to model plutonium (Pu) excretion from the analysis of a well-documented Pu wound case involving repeated diethylene-triamine-penta-acetic acid (DTPA) perfusions up to 390 d and monitoring up to 3109 d. Three modelling approaches were simultaneously applied involving: (1) release of soluble Pu from the wound, estimated with the ICRP66 dissolution model, (2) systemic behaviour of Pu by using ICRP67 model, but also two new models recently reported and (3) additional 'Pu-DTPA' compartments which transfer Pu directly to urinary compartment from blood, interstitial fluids and liver. The best fit of simulations to biological data was obtained by using the new Leggett's systemic model and assuming the presence of three DTPA compartments. Calculations have shown that DTPA treatments have contributed to a 3-fold reduction of the effective dose. Thus, reduction of doses associated with the DTPA treatments can be estimated by modelling which is useful to improve the efficacy of a DTPA treatment schedule based on a diminution of risk.


Asunto(s)
Bioensayo/métodos , Ácido Pentético/administración & dosificación , Plutonio/farmacocinética , Plutonio/toxicidad , Traumatismos por Radiación/metabolismo , Traumatismos por Radiación/prevención & control , Radiometría/métodos , Heridas Penetrantes/metabolismo , Adulto , Carga Corporal (Radioterapia) , Quelantes/administración & dosificación , Simulación por Computador , Cuerpos Extraños/complicaciones , Cuerpos Extraños/dietoterapia , Cuerpos Extraños/metabolismo , Humanos , Cinética , Masculino , Tasa de Depuración Metabólica , Modelos Biológicos , Traumatismos por Radiación/etiología , Protectores contra Radiación/administración & dosificación , Efectividad Biológica Relativa , Resultado del Tratamiento , Heridas Penetrantes/tratamiento farmacológico , Heridas Penetrantes/etiología
6.
J Natl Cancer Inst ; 89(15): 1152-60, 1997 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-9262254

RESUMEN

BACKGROUND: A variety of studies have supported the finding that regular intake of aspirin (acetylsalicylic acid) or nonsteroidal anti-inflammatory agents can affect colorectal cancer carcinogenesis. These agents inhibit the synthesis of prostaglandins. High levels of prostaglandins are observed in colon cancer tissues. PURPOSE: Experiments were planned to determine the lowest dose of aspirin that can markedly suppress the levels of mucosal prostaglandins E2 and F(2alpha) in colorectal mucosa and to determine whether a relationship exists between these levels and plasma levels of both acetylsalicylic acid and its metabolite, salicylic acid. METHODS: Healthy men and women aged 18 years or older participated in the study. The participants took a single, daily dose of aspirin (40.5, 81, 162, 324, or 648 mg) or a placebo for 14 days. Colorectal biopsy specimens were taken at baseline, 24 hours after the first dose of aspirin, and 24-30 hours and 72-78 hours after the last, i.e., fourteenth, daily dose of aspirin. The biopsy specimens were assayed for prostaglandins E2 and F(2alpha) by use of a competitive enzyme immunoassay. Plasma concentrations of acetylsalicylic acid and salicylic acid were determined by use of high-performance liquid chromatography. All P values are two-sided. RESULTS: A total of 65 subjects (10 receiving placebo, groups of 10 each receiving 40.5, 81, 162, or 324 mg of aspirin, and a group of 15 receiving 648 mg of aspirin) completed the protocol. One subject reported unacceptable drug-induced toxic effects and did not complete the protocol; other subjects reported acceptable side effects. The lowest dose to significantly suppress colorectal mucosal prostaglandin E2 concentrations from baseline at 24 hours after the first dose (by 22.6%; P = .002) and at 24-30 hours after the last dose (by 14.2%; P = .021) was 162 mg. At 72-78 hours after the last dose, there was significant suppression for subjects receiving 81 mg (by 23.7%; P = .008). The lowest dose to significantly suppress colorectal mucosal prostaglandin F(2alpha) concentrations from baseline at 24 hours after the first dose (by 18.3%; P = .032) was 324 mg. The lowest dose causing a marked reduction in the level of prostaglandin F(2alpha) at 24-30 hours (by 15.1%; P = .003) and 72-78 hours (by 23.0%; P = .0002) after the last dose was 40.5 mg. No detectable amounts of acetylsalicylic acid or salicylic acid were present in the plasma at any of the biopsy time points. CONCLUSIONS: The lowest doses of aspirin taken daily for 14 days to significantly suppress concentrations of colorectal mucosal prostaglandins E2 and F(2alpha) were 81 and 40.5 mg, respectively. The suppression occurred without detectable amounts of aspirin or salicylic acid in the plasma at the time points studied. On the basis of these observations, we recommend a single, daily dose of 81 mg of aspirin in future studies of this drug as a chemopreventive agent for colorectal cancer.


Asunto(s)
Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/farmacocinética , Aspirina/administración & dosificación , Aspirina/farmacocinética , Colon , Neoplasias Colorrectales/prevención & control , Mucosa Intestinal/metabolismo , Recto , Adulto , Antiinflamatorios no Esteroideos/sangre , Aspirina/sangre , Neoplasias Colorrectales/metabolismo , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prostaglandinas/metabolismo , Salicilatos/sangre , Ácido Salicílico , Factores de Tiempo
7.
Biotech Histochem ; 90(3): 184-9, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25434394

RESUMEN

In vitro bioassay has been used extensively to test the effects of culturing cancer cells in sera from humans participating in dietary interventions, i.e, studies of modified intake of nutrients for the purpose of reducing cancer risk or progression. It has been hypothesized that cell proliferation rates determined by the in vitro bioassay indicate whether modification of dietary intake could decrease cancer cell growth in vivo. It has been suggested, however, that the in vitro bioassay may not correlate with tumor cell proliferation rates in prostate cancer. We investigated the concordance of cell proliferation rates from surgically excised prostate tumor tissue with the in vitro bioassay using sera from matched patients. We used samples from an earlier randomized clinical trial that showed that supplementation with flaxseed significantly inhibited prostate cancer cell proliferation rates in vivo as indicated by Ki67 staining in tumor specimens. Proliferation rates of LNCaP, DU145 and PC3 cell lines cultured in 10% human sera from participants in the flaxseed trial were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Spearman's Rho correlation coefficients (ρ) indicated no association between Ki67 staining in prostate tumors and the in vitro bioassay for the three cell lines. These disparate findings suggest that the in vitro bioassay may not provide an accurate assessment of the environment in vivo.


Asunto(s)
Bioensayo/métodos , Proliferación Celular/efectos de los fármacos , Neoplasias de la Próstata/dietoterapia , Neoplasias de la Próstata/patología , Anciano , Línea Celular Tumoral , Dieta con Restricción de Grasas , Suplementos Dietéticos , Lino/química , Humanos , Antígeno Ki-67/metabolismo , Masculino , Persona de Mediana Edad , Prostatectomía , Semillas
8.
Crit Rev Oncol Hematol ; 33(3): 169-85, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10789491

RESUMEN

Cervix carcinoma is an important health problem world-wide, being the second most common cancer among women, ranking first in many developing countries. A number of important epidemiological risk factors have been identified as contributing to the development of CIN and invasive cervix carcinoma. Of key importance is infection with human papillomavirus (HPV), which is the primary risk factor. There are evolving primary and secondary preventive strategies that could further reduce the burden from cervical carcinoma. The possible primary preventive strategies include risk reduction, diet or dietary supplements, HPV vaccines, and other chemopreventive agents. The possible advances in secondary preventive strategies include new technologies for Pap smears, HPV typing triage, and other adjuvant screening procedures. The impact of these strategies will depend upon evidence to support their use along with the characteristics of the population and environment in which they are used.


Asunto(s)
Anticarcinógenos/uso terapéutico , Antioxidantes/uso terapéutico , Carcinoma de Células Escamosas/prevención & control , Neoplasias del Cuello Uterino/prevención & control , Vitaminas/uso terapéutico , Ácido Ascórbico/uso terapéutico , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/etiología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/virología , Ensayos Clínicos como Asunto , Colposcopía/métodos , Dieta , Femenino , Ácido Fólico/uso terapéutico , Humanos , Procesamiento de Imagen Asistido por Computador , Tamizaje Masivo/métodos , Necesidades Nutricionales , Prueba de Papanicolaou , Papillomaviridae/genética , Papillomaviridae/aislamiento & purificación , Papillomaviridae/patogenicidad , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/patología , Fotoquimioterapia , Factores de Riesgo , Infecciones Tumorales por Virus/epidemiología , Infecciones Tumorales por Virus/genética , Infecciones Tumorales por Virus/patología , Displasia del Cuello del Útero/epidemiología , Displasia del Cuello del Útero/virología , Displasia del Cuello del Útero/etiología , Displasia del Cuello del Útero/metabolismo , Displasia del Cuello del Útero/prevención & control , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/etiología , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/virología , Frotis Vaginal/instrumentación , Frotis Vaginal/métodos , Vacunas Virales , Vitamina E/uso terapéutico , beta Caroteno/uso terapéutico
9.
Cancer Epidemiol Biomarkers Prev ; 10(5): 447-53, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11352853

RESUMEN

UNLABELLED: Development of potential cancer chemopreventive drugs involves the systematic evaluation of these drugs in preliminary Phase I and II studies in human beings to identify the optimal drug dose, drug toxicity, and surrogate end point biomarker modulation. OBJECTIVES: We tested the hypothesis that aspirin, at a single, once-daily 81-mg dose, will reduce colonic mucosal concentration of prostaglandin estradiol (E2) in individuals at high risk for colorectal cancer development similar to our prior observations in a young normal-risk population. METHODS: Aspirin was administered at a dose of 81 mg once daily for 28 days in a cohort of 92 matched high-risk and normal-risk colorectal cancer subjects. Prostaglandin E2 and cyclooxygenase expression were assayed from distal sigmoid biopsies from all of the subjects before and after treatment. RESULTS: The mean prostaglandin E2 for normal-risk subjects before aspirin treatment was 11.3 +/- 1.7 pg/microg (mean +/- SE) tissue protein and after aspirin treatment was 4.9 +/- 0.91 pg/microg tissue protein (P < 0.0001). In high-risk subjects, mean pretreatment prostaglandin E2 was 14.4 +/- 1.7 pg/microg tissue protein and after aspirin treatment was 4.7 +/- 0.70 pg/microg tissue protein (P < 0.0001). Aspirin treatment did not alter cyclooxygenase-1 protein expression. CONCLUSIONS: Aspirin treatment at a dose of 81 mg reduces colorectal mucosal prostaglandin E2 concentration after 28 daily doses. Risk for colorectal carcinoma did not modify colorectal mucosal baseline or post-aspirin prostaglandin E2, or cyclooxygenase expression. Colorectal mucosal prostaglandin concentration may be used as a "drug-effect surrogate biomarker," that is, a surrogate to assess sufficient delivery and tissue effect of a chemopreventive agent.


Asunto(s)
Aspirina/administración & dosificación , Biomarcadores de Tumor/análisis , Carcinoma/prevención & control , Neoplasias Colorrectales/prevención & control , Dinoprostona/análisis , Mucosa Intestinal/química , Mucosa Intestinal/efectos de los fármacos , Prostaglandina-Endoperóxido Sintasas/metabolismo , Adulto , Anciano , Análisis de Varianza , Biopsia con Aguja , Carcinoma/epidemiología , Carcinoma/patología , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/patología , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Prostaglandina-Endoperóxido Sintasas/efectos de los fármacos , Valores de Referencia , Medición de Riesgo , Sensibilidad y Especificidad
10.
Brain Res ; 874(1): 30-6, 2000 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-10936221

RESUMEN

Energy balance is achieved by means of a concomitant control of both food intake and energy expenditure. Leptin, synthesized in the adipose tissue, acts on brain structures and lowers body weight by inhibiting food intake and in parallel by enhancing energy expenditure i.e. metabolism or one of its components. Recording distinctly these components allowed us to assess the effect of an acute intracerebroventricular injection of leptin on both feeding pattern and background metabolism (i.e. energy expenditure free from the part of locomotor activity), respiratory quotient, feeding-related metabolism and locomotor activity-related metabolism. Leptin injection to Sprague-Dawley male rats induced an inhibition of feeding that began 90 min after the treatment and lasted 1 h before to return to the control feeding pattern level. Considering this late behavioral effect, it appeared that leptin may act during the postprandial period so that we recorded the different metabolic parameters following a 3 g calibrated meal itself preceded by leptin vs. artificial cerebrospinal fluid injection. Postprandial respiratory quotient was rapidly lowered in leptin-treated animals and subsequent background metabolism increased for 6 h. Thus it appeared that leptin increased the duration of the postprandial metabolic rate via the recruitment of endogenous fat stores. Enhancement in the thermic effect of food may be the reason for feeding behavior inhibition to be delayed.


Asunto(s)
Leptina/farmacología , Metabolismo/efectos de los fármacos , Animales , Conducta Animal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Inyecciones Intraventriculares , Masculino , Ratones , Actividad Motora/efectos de los fármacos , Periodo Posprandial , Ratas , Ratas Sprague-Dawley , Respiración/efectos de los fármacos
11.
Brain Res ; 846(1): 23-9, 1999 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-10536210

RESUMEN

The effects of ventromedial hypothalamic (VMH) stimulation on various metabolic parameters in freely moving animals were measured using a specific indirect calorimetric chamber associated with a quantitative measurement of locomotor activity, which allows the separate measurement of locomotor energy expenditure from that of background metabolism, BM (free from expenses due to locomotion). To obtain circumscribed VMH stimulation, a slight-intensity (20-25 microA) bipolar, constant current was applied for 15 min at the beginning of the dark phase on ad libitum fed rats. The VMH stimulation suppressed feeding for 40 min, then animals progressively recovered within the subsequent 60 min as shown by comparison with the control group. On different days, the same stimulation parameters were applied while food was unavailable, and metabolic parameters were recorded. An increase in BM lasting 30 min was observed. This increase in metabolic rate was sustained by means of a recruitment of lipid stores as indicated by a concomitant drop in respiratory quotient. These observations indicate that the VMH is part of the sympathetic nervous system, capable of inducing lipolysis. The sequence of metabolic and feeding events may then in part be due to VMH-induced lipolysis that provides more fuel to the metabolic economy, raising the BM, which in turn decreases hunger.


Asunto(s)
Grasas/metabolismo , Conducta Alimentaria/fisiología , Obesidad/metabolismo , Núcleo Hipotalámico Ventromedial/fisiología , Animales , Metabolismo Basal/fisiología , Conducta Animal/fisiología , Respiración de la Célula/fisiología , Estimulación Eléctrica , Lipólisis/fisiología , Masculino , Ratas , Ratas Wistar
12.
Brain Res ; 700(1-2): 121-8, 1995 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-8624701

RESUMEN

Energy metabolism and food intake effect each other. Many studies demonstrated that the lateral hypothalamus (LH) participates in the control of both feeding behavior and energy metabolism. We assessed the effect of a bipolar near threshold feeding eliciting electrical stimulation of the LH first on the feeding response and then on the background metabolism (metabolism free from the part due to locomotion) and respiratory quotient (RQ), on Wistar male rats, during either the light or the dark phase of the nycthemeron. LH stimulation resulted in a delayed and rather long increase in background metabolism that was more dramatic during the light phase. This metabolic response paralleled the delayed feeding response (more than 10 min) we obtained during behavioral tests. The increase in energy production was sustained by release of energy substrates from the endogenous stores, and this showed a circadian dependence. Mainly carbohydrates (rise in RQ) were used during the light phase stimulation whereas lipids (decrease in RQ) were released in the dark phase.


Asunto(s)
Ritmo Circadiano/fisiología , Metabolismo Energético/fisiología , Conducta Alimentaria/fisiología , Área Hipotalámica Lateral/fisiología , Análisis de Varianza , Animales , Metabolismo Basal , Estimulación Eléctrica , Masculino , Consumo de Oxígeno/fisiología , Ratas , Ratas Wistar
13.
Hematol Oncol Clin North Am ; 12(5): 1115-34, viii-ix, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9888023

RESUMEN

Cervical carcinoma creates a worldwide, significant population burden that potentially could be reduced by new preventive strategies for cervical cancer such as chemoprevention. Given the vast array of clinical and molecular information available relating to cervical cancer and the precursor lesions along with a growing number of new molecular techniques, a model is needed to guide further investigation. Such a model would facilitate research design, guide hypothesis development and testing, and focus the use of molecular data collection and analysis. This article reviews the clinical and molecular data of cervical cancer and the precursor lesions in order to develop a model for chemoprevention research in cervical cancer.


Asunto(s)
Quimioprevención , Neoplasias del Cuello Uterino/prevención & control , Femenino , Humanos , Neoplasias del Cuello Uterino/fisiopatología
14.
Hematol Oncol Clin North Am ; 12(5): 1079-113, viii, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9888022

RESUMEN

Colon cancer is a common malignancy in the westernized world and is incurable in its advanced stages. This article summarizes the currently available information on colorectal cancer chemoprevention. A brief outline of the incidence and etiologic factors is followed by a discussion of the evidence on which chemopreventive strategies for colon cancer are modeled. This includes a description of the development of surrogate endpoint biomarkers and experimental models to study colorectal cancer chemopreventives, a review of the promising colorectal cancer chemopreventives, and a discussion of the issues to be addressed in the design of future chemoprevention trials. The article concludes with an emphasis on the development and validation of biomarkers and selection of high-risk cohorts using genetic and epidemiologic tools as the main goals of future colon cancer chemoprevention trials before large-scale, risk-reduction trials are conducted.


Asunto(s)
Quimioprevención/métodos , Neoplasias del Colon/prevención & control , Animales , Ensayos Clínicos como Asunto , Neoplasias Colorrectales/prevención & control , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ratones
15.
Health Psychol ; 18(6): 570-8, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10619530

RESUMEN

Identifying major influences on food choice is an important component of nutrition intervention research. Sensitivity to the bitter taste of 6-n-propylthiouracil (PROP) and self-reported preferences for meats, fats, vegetables, and fruit were examined in 329 female breast care patients. Intakes of fat, saturated fat, fiber, folate, and vitamin C, established using 4-day food diaries, were the chief health outcome variables. The strongest predictor of food preferences was age. Preferences were linked to food intakes. Older women consumed less energy and saturated fat and more dietary fiber and vitamin C than did younger women. Age-related decline in taste sensitivity to PROP was associated with increased liking for bitter cruciferous vegetables. Age-associated changes in food preferences and eating habits have implications for the dietary approach to cancer prevention and control.


Asunto(s)
Neoplasias de la Mama/prevención & control , Dieta , Preferencias Alimentarias , Umbral Gustativo/fisiología , Adulto , Factores de Edad , Grasas de la Dieta/administración & dosificación , Fibras de la Dieta/administración & dosificación , Femenino , Encuestas Epidemiológicas , Humanos , Persona de Mediana Edad , Estado Nutricional , Verduras
16.
Acad Med ; 67(6): 385-97, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1596337

RESUMEN

What environmental factors stimulate and maintain research productivity? To answer this question, the authors conducted an extensive review of articles and books on research productivity published from the mid-1960s through 1990. This review revealed that a consistent set of 12 characteristics was found in research-conducive environments: (1) clear goals that serve a coordinating function, (2) research emphasis, (3) distinctive culture, (4) positive group climate, (5) assertive participative governance, (6) decentralized organization, (7) frequent communication, (8) accessible resources, particularly human, (9) sufficient size, age, and diversity of the research group, (10) appropriate rewards, (11) concentration on recruitment and selection, and (12) leadership with research expertise and skill in both initiating appropriate organizational structure and using participatory management practices. Some of these characteristics are not surprising, although some findings were unexpected, such as that participative governance correlated consistently with research productivity. The differential impact of each of these 12 characteristics is unclear. It is clear, however, that the leader has a disproportionate impact through his or her influence on all of the other characteristics. Yet, an overarching feature of these characteristics is their interdependency. These factors do not operate in research groups as isolated characteristics. Rather, they are like fine threads of a whole fabric: individual, yet when interwoven, providing a strong, supportive, and stimulating backdrop for the researcher. The authors conclude that while at a distance the productive research enterprise looks like a highly robust entity, upon closer inspection it is revealed to be a delicate structure highly dependent on the existence and effective working of numerous individual, organizational, and leadership characteristics.


Asunto(s)
Liderazgo , Investigadores/organización & administración , Investigación/organización & administración , Actitud , Comunicación , Ambiente , Humanos
17.
Physiol Behav ; 62(6): 1259-64, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9383111

RESUMEN

Because energy homeostasis depends on a continuous balance between food intake, energy expenditure, and energy storage, it was expected that neuropeptide Y (NPY) could act not only on food intake but also on metabolic parameters. Using an original calorimetric device that allows the computation of the background metabolism (energy expenditure free from the cost of locomotor activity), we assessed the effect of a microinjection of NPY upon the quantitative (background metabolism, thermic effect of food) and qualitative (respiratory quotient) components of energy metabolism. NPY was injected into the juxtafornical hypothalamus at a dose that promotes feeding behavior (1 microg/0.5 microL) and enhances locomotor activity. Although total metabolism was increased proportionally to locomotion, no effect of NPY on background metabolism was observed when no food was available. Only following a calibrated meal given 30 min after the microinjection did NPY induce a delayed decrease in respiratory quotient whereas the postprandial background metabolism remained unaffected. In conclusion, only the new-generation calorimeters can show that the NPY-induced rise in overall metabolic rate is entirely accounted for by the unavoidable enhancement in locomotor activity and that the only metabolic effect of NPY is the delayed postprandial respiratory quotient decrease, suggesting a postabsorptive orientation toward more lipid utilization.


Asunto(s)
Metabolismo Basal/efectos de los fármacos , Conducta Alimentaria/efectos de los fármacos , Neuropéptido Y/farmacología , Animales , Temperatura Corporal/efectos de los fármacos , Calorimetría , Metabolismo Energético/efectos de los fármacos , Alimentos , Hipotálamo , Inyecciones , Masculino , Actividad Motora/efectos de los fármacos , Neuropéptido Y/administración & dosificación , Ratas , Ratas Wistar , Mecánica Respiratoria/efectos de los fármacos
18.
J Am Diet Assoc ; 100(2): 191-7, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10670391

RESUMEN

OBJECTIVE: To explore links between genetic responsiveness to the bitter taste of 6-n-propylthiouracil (PROP) and self-reported preferences for vegetables and fruit of female breast care patients. METHODS: PROP tasting was defined by detection thresholds and by perceived bitterness and hedonic ratings for PROP solutions. Nontasters, medium tasters, and supertasters were identified by their PROP thresholds and by the ratio of perceived bitterness of PROP to the perceived saltiness of sodium chloride solutions. Subjects rated preferences for vegetables and fruit using 9-point category scales. SUBJECTS/SETTING: A clinical sample of 170 patients with newly diagnosed breast cancer and 156 cancer-free control subjects were recruited from the University of Michigan Breast Care Center. STATISTICAL ANALYSES: Principal components factor analysis, one-way analyses of variance, and Pearson correlations and chi 2 tests were used to analyze taste and food preference data. RESULTS: Genetic responsiveness to PROP was associated with lower acceptance of cruciferous and selected green and raw vegetables (P < .05). Women who reported disliking such foods were medium tasters or supertasters of PROP. Preference ratings for fruit were unrelated to PROP taster status. APPLICATIONS/CONCLUSIONS: Women who are PROP tasters may be less likely to comply with dietary strategies for cancer prevention that emphasize consumption of cruciferous vegetables and bitter salad greens. Alternatively, PROP-sensitive women may seek to reduce bitter taste by adding fat, sugar, or salt.


Asunto(s)
Neoplasias de la Mama/prevención & control , Preferencias Alimentarias , Frutas , Gusto/genética , Verduras , Neoplasias de la Mama/genética , Estudios de Casos y Controles , Femenino , Humanos , Persona de Mediana Edad , Propiltiouracilo/química
19.
J Am Diet Assoc ; 101(10): 1167-74, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11678487

RESUMEN

OBJECTIVE: To examine whether diet intervention can promote increased vegetable and fruit intake, as reflected in increased plasma carotenoid and decreased plasma total homocysteine concentrations, in premenopausal women with cervical intraepithelial neoplasia, a precancerous condition. DESIGN: Randomized controlled diet intervention study. SUBJECTS: Fifty-three free-living premenopausal women who had been diagnosed with cervical intraepithelial neoplasia, were randomly assigned to an intervention (n = 27) or a control (n = 26) group. INTERVENTION: Individualized dietary counseling to increase vegetable and fruit intake. MAIN OUTCOME MEASURES: Diet was assessed by food frequency questionnaire. Plasma carotenoids and total homocysteine were measured at enrollment and at 6 months follow up. ANALYSIS: Associations between baseline plasma concentrations of carotenoids and homocysteine and influencing factors were examined with multiple regression analysis. Repeated measures analysis of variance was used to test for group by time effects in these plasma concentrations. Plasma carotenoids at baseline and 6 months in the study groups, and differences in homocysteine concentrations from baseline to 6 months, were compared with independent sample t tests. RESULTS: Repeated measures analysis of variance showed significant group by time effects (P<.01) in plasma carotenoid and homocysteine concentrations. In the intervention group, total plasma carotenoids increased by an average of 91%, from 2.04+/-0.13 (mean+/-standard error of the mean) to 3.90+/-0.56 micromol/L and plasma total homocysteine was reduced by 11%, from 9.01+/-0.40 to 8.10+/-0.44 micromol/L (P<.003). Neither changed significantly in the control group. APPLICATIONS: Individualized dietary counseling can effectively promote increased vegetable and fruit intake in premenopausal women. This dietary pattern may reduce risk for cancer and other chronic diseases and also promote an improvement in folate status.


Asunto(s)
Frutas , Lesiones Precancerosas/dietoterapia , Premenopausia , Displasia del Cuello del Útero/dietoterapia , Neoplasias del Cuello Uterino/dietoterapia , Verduras , Adulto , Carotenoides/sangre , Femenino , Ácido Fólico/sangre , Frutas/química , Promoción de la Salud , Homocisteína/sangre , Humanos , Persona de Mediana Edad , Lesiones Precancerosas/sangre , Análisis de Regresión , Encuestas y Cuestionarios , Neoplasias del Cuello Uterino/sangre , Verduras/química , Displasia del Cuello del Útero/sangre
20.
Fam Med ; 24(5): 382-5, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1526388

RESUMEN

BACKGROUND: Injuries are the number one cause of morbidity and mortality among children age 14 and younger in the United States, and motor vehicle crashes account for most of these injuries. Although child restraint devices (CRDs) have been shown to protect children involved in motor vehicle crashes, only minimal decreases in mortality and morbidity have occurred since their introduction. This study evaluated the accuracy and sources of adult knowledge about CRDs. METHODS: A self-administered questionnaire was completed by patients at a community-based family practice clinic to obtain demographic information, assess knowledge of recommendations for CRD use, and identify sources of this knowledge. RESULTS: Of the 368 participants, 36% were men, 52% were women, and 12% did not indicate gender. The frequencies of correct responses on positioning infants younger than nine months of age and weighing less than 20 lbs in a CRD were: upright, 47%; rear middle-seat location, 22%; and rear facing, 54%. For toddlers older than nine months who weighed more than 20 lbs, the frequencies of correct responses on positioning were: using a booster seat plus a seat belt, 71%; rear-middle location, 17%; and front facing, 66%. In addition, only 42% of the respondents correctly identified the booster seat as not crash-test certified, and 44% indicated that a CRD should not be reused after an accident. The majority of respondents indicated that the year of manufacture was important and that loose objects in the car were not safe. TV/radio (51%), newspaper/magazine (41%), and relatives (31%) were the most common sources of information about CRD use. CONCLUSION: Our findings suggest that a lack of knowledge about CRD use among adults contributes to improper use of these devices. This may explain the minimal effect CRD use has had on reducing morbidity and mortality of children from motor vehicle crashes.


Asunto(s)
Accidentes de Tránsito , Conocimientos, Actitudes y Práctica en Salud , Equipo Infantil , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Proyectos Piloto , Cinturones de Seguridad , Encuestas y Cuestionarios
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA