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1.
J Clin Endocrinol Metab ; 103(5): 1899-1909, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29506126

RESUMEN

Purpose: Chemicals with hormonelike activity, such as estrogenic isoflavones, may perturb human development. Infants exclusively fed soy-based formula are highly exposed to isoflavones, but their physiologic responses remain uncharacterized. Estrogen-responsive postnatal development was compared in infants exclusively fed soy formula, cow-milk formula, and breast milk. Methods: We enrolled 410 infants born in Philadelphia-area hospitals between 2010 and 2014; 283 were exclusively fed soy formula (n = 102), cow-milk formula (n = 111), or breast milk (n = 70) throughout the study (birth to 28 or 36 weeks for boys and girls, respectively). We repeatedly measured maturation index (MI) in vaginal and urethral epithelial cells using standard cytological methods, uterine volume and breast-bud diameter using ultrasound, and serum estradiol and follicle-stimulating hormone levels. We estimated MI, organ-growth, and hormone trajectories by diet using mixed-effects regression splines. Results: Maternal demographics did not differ between cow-milk-fed and soy-fed infants but did differ between formula-fed and breastfed infants. Vaginal-cell MI trended higher (P = 0.01) and uterine volume decreased more slowly (P = 0.01) in soy-fed girls compared with cow-milk-fed girls; however, their trajectories of breast-bud diameter and hormone concentrations did not differ. We observed no significant differences between boys fed cow-milk vs soy formula; estradiol was not detectable. Breastfed infants differed from soy-formula-fed infants in vaginal-cell MI, uterine volume, and girls' estradiol and boys' breast-bud diameter trajectories. Conclusions: Relative to girls fed cow-milk formula, those fed soy formula demonstrated tissue- and organ-level developmental trajectories consistent with response to exogenous estrogen exposure. Studies are needed to further evaluate the effects of soy on child development.


Asunto(s)
Mama/efectos de los fármacos , Desarrollo Infantil/efectos de los fármacos , Estrógenos/farmacología , Fórmulas Infantiles/química , Uretra/efectos de los fármacos , Útero/efectos de los fármacos , Animales , Mama/crecimiento & desarrollo , Bovinos , Femenino , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido , Isoflavonas/farmacología , Estudios Longitudinales , Masculino , Leche/química , Leche/fisiología , Leche Humana/química , Leche Humana/fisiología , Fitoestrógenos/farmacología , Uretra/crecimiento & desarrollo , Útero/crecimiento & desarrollo
4.
Nutr Res ; 33(7): 534-42, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23827127

RESUMEN

Lignans and flavonols are dietary phytoestrogens found at high concentrations in the Western Diet. They have potential to influence the timing of puberty. We hypothesized that greater consumption of these 2 phytoestrogens would be related to later age at pubertal onset among girls. Pubertal assessment and 24-hour diet recall data were available for 1178 girls, ages 6 to 8 years (mean 7.3 years) in the Breast Cancer and Environment Research Project Puberty Study. Lignan and flavonol intakes were mainly derived from fruit and vegetable consumption. Average consumption was 6.5 mg/d for flavonols and 0.6 mg/d for lignans. Highest flavonol consumption (>5 mg/d) was associated with later breast development (adjusted hazards ratio [HR]: 0.74, 95% CI: [0.61-0.91]) compared to 2 to 5 mg/d (adjusted HR: 0.84, 95% CI: [0.70-1.0]) and <2 mg/d (referent group; P-trend = .006). Flavonol intake was not associated with pubic hair development. Lignan intake was not associated with either breast or pubic hair development. Dietary intake was only weakly correlated with urinary enterolactone, a biomarker for lignans (RS = 0.13). Consistent with biologic properties of phytoestrogens that indicate hormonal activity, their consumption may be associated with reproductive end points, even in childhood.


Asunto(s)
Mama/efectos de los fármacos , Dieta , Flavonoles/farmacología , Lignanos/farmacología , Fitoestrógenos/farmacología , Extractos Vegetales/farmacología , Pubertad/efectos de los fármacos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/orina , Factores de Edad , Biomarcadores/orina , Mama/crecimiento & desarrollo , Niño , Femenino , Cabello/efectos de los fármacos , Cabello/crecimiento & desarrollo , Humanos , Lignanos/orina , Estudios Longitudinales
6.
Gynecol Endocrinol ; 29(3): 209-12, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23194023

RESUMEN

OBJECTIVE: To assess the safety of a nutraceutical compound containing soy isoflavones and Lactobacillus sporogenes on endometrium, breast and liver function. SETTING: Outpatient Menopausal Clinic. STUDY DESIGN: 130 healthy postmenopausal women suffering from menopausal symptoms were randomized to receive soy isoflavones 60 mg and Lactobacillus sporogenes 1 billion spores (group E: 65 women) or calcium and vitamin D3 (group C: 65 women). Safety of the treatment was assessed at baseline and after 1 year taking into account endometrial thickness, mammographic density, serum levels of transaminases, γ-GT and bilirubin. Efficacy of the treatment was evaluated rating the score of menopausal symptoms at baseline and every 3 months. The statistical analysis was carried out with χ², Fisher exact's test and ANOVA. RESULTS: After 12 months of treatment mammographic density, endometrial thickness and hepatic function did not show significant differences between groups, while menopausal symptoms were progressively and significantly reduced in severity and frequency during treatment with soy isoflavones plus Lactobacillus sporogenes versus calcium plus vitamin D3. CONCLUSION: A 12 months treatment with a nutraceutical compound based on isoflavones and Lactobacillus sporogenes at the recommended doses is safe for endometrium, mammary glands and liver function in postmenopausal women.


Asunto(s)
Suplementos Dietéticos , Glycine max/química , Sofocos/prevención & control , Isoflavonas/uso terapéutico , Lactobacillus , Posmenopausia , Probióticos/uso terapéutico , Mama/crecimiento & desarrollo , Neoplasias de la Mama/prevención & control , Contraindicaciones , Suplementos Dietéticos/efectos adversos , Hiperplasia Endometrial/prevención & control , Endometrio/crecimiento & desarrollo , Terapia de Reemplazo de Estrógeno/efectos adversos , Femenino , Insuficiencia Hepática/prevención & control , Sofocos/fisiopatología , Humanos , Isoflavonas/efectos adversos , Hígado/crecimiento & desarrollo , Persona de Mediana Edad , Probióticos/efectos adversos , Semillas/química , Índice de Severidad de la Enfermedad
7.
Int J Dev Biol ; 55(7-9): 869-78, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22161842

RESUMEN

The present work reviews recent findings related to the action of steroidal (physiological) estrogens on normal mammary gland development and carcinogenesis, as well as effects of related environmental mediators (phyto- and xeno-estrogens), the role of which remains controversial. Orchestration by estrogen receptors (i.e. ERα and ERß) and coregulators of growth, apoptosis and differentiation of epithelial cells, directed our analysis. The bidirectional coordination between epithelium and stroma in parallel with maintenance of stemness are also investigated. The relevance of nuclear and extranuclear localization of ERs and other eventual estrogen binding sites, mediating differential actions in regard to these various topics, is critically addressed to delineate the importance of direct and indirect activation procedures and delicate feedback loops (ligand-induced or/and cross-talk activation, respectively). The inclusion of the outlined regulatory concepts in drug design programs for the prevention and treatment of breast cancer may have potent effects.


Asunto(s)
Neoplasias de la Mama/etiología , Mama/crecimiento & desarrollo , Estrógenos/farmacología , Estrógenos/fisiología , Fitoestrógenos/farmacología , Animales , Mama/efectos de los fármacos , Mama/fisiología , Neoplasias de la Mama/patología , Neoplasias de la Mama/fisiopatología , Carcinógenos Ambientales/toxicidad , Contaminantes Ambientales/toxicidad , Congéneres del Estradiol/toxicidad , Femenino , Humanos , Isoflavonas/farmacología , Glándulas Mamarias Animales/efectos de los fármacos , Glándulas Mamarias Animales/crecimiento & desarrollo , Glándulas Mamarias Animales/fisiología , Ratones , Modelos Biológicos , Fitoestrógenos/toxicidad , Receptor Cross-Talk , Receptores de Estrógenos/fisiología , Transducción de Señal , Células Madre/citología , Células Madre/efectos de los fármacos , Células Madre/fisiología
8.
Nutr Cancer ; 63(3): 410-20, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21391126

RESUMEN

Based on the importance of early-life events in breast cancer risk, we have investigated the effects of high-fat diets on maturation, mammary gland development, and its susceptibility to transformation. Female Sprague-Dawley rats were fed a lowfat (LF), high corn oil (HCO), or high extra-virgin olive oil (HOO) diet from weaning and gavaged with 7,12-dimethylbenz[a]anthracene. Body weight and mass increased in the HCO group compared to the LF group. The vaginal opening was advanced in both high-fat groups, especially in the HCO group. This HCO group also had increased body weight around puberty, more corpora lutea at post-puberty, and tended to have higher kisspeptin levels in the hypothalamus. Both high-fat diets induced subtle modifications in the morphology of the mammary gland, with no changes on ß-casein or hormone receptors expression in the gland. The HCO diet had a clearly stimulating effect of carcinogenesis, inducing the earliest appearance of tumors and the highest tumor incidence and yield, whereas the HOO diet seemed to have a weak enhancing effect, increasing tumor yield. Our data suggest a strong influence of the HCO diet in sexual maturation and mammary cancer risk, while rats fed the HOO diet were more similar to the controls.


Asunto(s)
Mama/patología , Aceite de Maíz/administración & dosificación , Grasas de la Dieta/administración & dosificación , Aceites de Plantas/administración & dosificación , Maduración Sexual , 9,10-Dimetil-1,2-benzantraceno/toxicidad , Secuencia de Aminoácidos , Análisis de Varianza , Animales , Peso Corporal , Mama/crecimiento & desarrollo , Caseínas/análisis , Caseínas/genética , Transformación Celular Neoplásica/patología , Receptor alfa de Estrógeno/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Kisspeptinas , Neoplasias Mamarias Experimentales/metabolismo , Neoplasias Mamarias Experimentales/patología , Datos de Secuencia Molecular , Aceite de Oliva , Ovario/crecimiento & desarrollo , Ovario/patología , Proteínas/genética , Proteínas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley
9.
Am J Clin Nutr ; 92(3): 556-64, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20631200

RESUMEN

BACKGROUND: It has been suggested that phytoestrogens and dietary fiber can affect puberty timing. OBJECTIVE: We examined whether intake of isoflavone and fiber in healthy white children before their pubertal growth spurt [age at take-off (ATO)] was associated with puberty timing. DESIGN: Multivariate regression analyses were performed in 227 DONALD (DOrtmund Nutritional and Anthropometric Longitudinally Designed) Study participants with 3-d weighed dietary records and information on potential confounders at baseline (1 and 2 y before ATO). In a subsample (n = 111), urinary isoflavones were determined in 24-h urine samples by gas chromatography-mass spectrometry analysis. Puberty timing was examined by using ATO and chronologic ages at pubertal stage 2 for breast development (B2) or gonadal development, peak height velocity (PHV), and menarche or voice break. RESULTS: Girls whose diet was in the highest dietary isoflavone tertile experienced Tanner stage 2 for breast development ap 0.7 y later and reached PHV ap 0.6 y later than did girls whose diet was in the lowest isoflavone tertile [age (95% CI) at B2: 10.7 y (10.4, 10.9 y) compared with 10.0 y ( 9.7, 10.3 y), respectively; P for trend = 0.04; age at PHV: 11.9 y (11.6, 12.2 y) compared with 11.3 y (11.0, 11.6 y), respectively; P for trend = 0.04; adjusted for body mass index z score and fiber intake]. In boys, dietary isoflavones were not associated with pubertal markers. Urinary isoflavone and dietary fiber intakes were not associated with pubertal markers. CONCLUSIONS: Girls, but not boys, with higher prepubertal isoflavone intakes appear to enter puberty at a later age. Fiber intake in this sample of healthy white girls and boys was not relevant for puberty timing.


Asunto(s)
Dieta , Fibras de la Dieta/farmacología , Isoflavonas/farmacología , Fitoestrógenos/farmacología , Pubertad/efectos de los fármacos , Factores de Edad , Estatura/fisiología , Mama/efectos de los fármacos , Mama/crecimiento & desarrollo , Niño , Registros de Dieta , Fibras de la Dieta/administración & dosificación , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Isoflavonas/administración & dosificación , Isoflavonas/orina , Estudios Longitudinales , Masculino , Menarquia , Fitoestrógenos/administración & dosificación , Fitoestrógenos/orina , Análisis de Regresión , Factores Sexuales
10.
Environ Res ; 107(3): 393-400, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18479682

RESUMEN

BACKGROUND: Hormonally active environmental exposures are suspected to alter onset of puberty in girls, but research on this question has been very limited. OBJECTIVE: We investigated pubertal status in relation to hormonally active environmental exposures among a multiethnic group of 192 healthy 9-year-old girls residing in New York City. METHODS: Information was collected on breast and pubic hair stages, weight and height. Phytoestrogen intake was estimated from a food-frequency questionnaire. Three phytoestrogens and bis-phenolA (BPA) were measured in urine. In a subset, 1,1'-dichloro-2,2'-bis(4-chlorophenyl)ethylene (DDE), polychlorinated biphenyls (PCBs) were measured in blood plasma and lead (Pb) in blood. Associations of exposures with pubertal stages (present=stage 2+ vs absent=stage 1) were examined using t-tests and Poisson multivariate regression to derive prevalence ratios (PR, 95%-confidence limits [CI]). RESULTS: Breast development was present in 53% of girls. DDE, Pb, and dietary intakes of phytoestrogens were not significantly associated with breast stage. Urinary phytoestrogen biomarker concentrations were lower among girls with breast development compared with no development. In multivariate models, main effects were strongest for two urinary isoflavones, daidzein (PR 0.89 [0.83-0.96] per ln microg/g creatinine) and genistein (0.94 [0.88-1.01]). Body mass index (BMI) is a hormonally relevant, strong risk factor for breast development. Therefore, BMI-modification of exposure effects was examined, and associations became stronger. Delayed breast development was observed among girls with below-median BMI and third tertile (high exposure) of urinary daidzein (PR 0.46 [0.26-0.78]); a similar effect was seen with genistein, comparing to girls >or= median BMI and lowest two tertiles (combined) of these isoflavones. With urinary enterolactone a phytoestrogen effect was seen only among girls with high BMI, where breast development was delayed among those with high urinary enterolactone (PR 0.55 [0.32-0.96] for the upper tertile vs lower two combined). There was no main effect of PCBs on breast stage, but girls with below-median BMI and >or= median PCB levels had reduced risk for breast development (any vs none) compared with other BMI-PCB groups. No biomarkers were associated with hair development, which was present in 31% of girls. CONCLUSIONS: Phytoestrogens and PCBs are environmental exposures that may delay breast development, especially in conjunction with BMI, which governs the endogenous hormonal milieu. Further research to confirm these findings may improve our understanding of the role of early life development in breast cancer risk and other chronic diseases related to obesity.


Asunto(s)
Disruptores Endocrinos/toxicidad , Exposición a Riesgos Ambientales/análisis , Fitoestrógenos/toxicidad , Bifenilos Policlorados/toxicidad , Pubertad/efectos de los fármacos , Índice de Masa Corporal , Mama/crecimiento & desarrollo , Niño , Disruptores Endocrinos/orina , Femenino , Cabello/crecimiento & desarrollo , Humanos , Ciudad de Nueva York , Fitoestrógenos/orina , Bifenilos Policlorados/orina , Población Urbana
11.
J Pediatr Gastroenterol Nutr ; 46(2): 191-5, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18223379

RESUMEN

OBJECTIVE: To evaluate the estrogenic effect of soy-based formulas in female infants. These formulas contain significant amounts of phytoestrogens, compounds with structural similarity to estradiol. PATIENTS AND METHODS: A cross-sectional study consisting of 694 female infants ages 3 to 24 months that consecutively attended 10 general pediatric clinics, none of them having been referred for breast development. The presence of breast buds served as a marker for the endocrine effect of soy-derived phytoestrogens. RESULTS: Of the participants, 92 had consumed soy formulas for more than 3 months. Breast tissue was more prevalent in the second year of life in infants fed soy-based formula vs those that were breast-fed and those fed dairy-based formula (22.0% vs 10.3%; P = 0.02) with an odds ratio of 2.45 (95% confidence interval 1.11-5.39). No differences in breast bud prevalence were observed during the first year of life. Unlike infants on dairy-based formulas and breast-feeding, infants fed a soy-based formula did not demonstrate a decline in the prevalence of breast during the second year of life. CONCLUSIONS: We suggest that phytoestrogens impose a preserving effect on breast tissue that is evolved in early infancy, leading eventually to a slower waning of infantile breast tissue.


Asunto(s)
Mama/efectos de los fármacos , Mama/crecimiento & desarrollo , Fórmulas Infantiles , Fitoestrógenos/farmacología , Leche de Soja/química , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Fitoestrógenos/administración & dosificación , Factores de Riesgo , Estadísticas no Paramétricas , Factores de Tiempo
12.
Arq Bras Endocrinol Metabol ; 51(3): 500-3, 2007 Apr.
Artículo en Portugués | MEDLINE | ID: mdl-17546252

RESUMEN

Precocious thelarche is the breast development before 8 years of age with two peaks of incidence during the first two years of life and after 6 years of age. A 4.75-year-old girl presented with thelarche associated to an excessive intake of phytoestrogens (phye). Tanner development B2P1-2, hormonal levels and pelvic US were compatible with peripheral precocious puberty. During follow-up, a daily intake of soy-based foods was observed (> 40 mg phye/day). Soy is rich in phytoestrogens, mainly genistein and daidzein. Although phye are less strong than estradiol, its concentration could be from 13,000 to 22,000 times stronger in children fed only by soy-based formulas. Parents were advised and soy intake was reduced to once a week. Progression of pubertal development ceased at B2-3P1. The patient, now 8.66 years old, keeps growing with similar bone and chronological ages. Some questions related to industrial food security, mainly the soy-based food, remain without precise answer. Although it is well known the entity of non-progressive precocious puberty and premature thelarche, pubertal development in this case was strongly related to excessive daily intake of soy and other phye-rich food that could trigger puberty as endocrine disruptor.


Asunto(s)
Mama/crecimiento & desarrollo , Fitoestrógenos/efectos adversos , Pubertad Precoz/inducido químicamente , Alimentos de Soja/efectos adversos , Mama/efectos de los fármacos , Preescolar , Disruptores Endocrinos/efectos adversos , Femenino , Humanos , Fitoestrógenos/administración & dosificación , Glycine max
13.
Arq. bras. endocrinol. metab ; 51(3): 500-503, abr. 2007. tab
Artículo en Portugués | LILACS | ID: lil-452194

RESUMEN

Telarca precoce, desenvolvimento mamário antes dos 8 anos de idade, apresenta dois picos de incidência, nos dois primeiros anos de vida e após os 6 anos de idade. Uma menina de 4,75 anos apresentou-se com telarca associada à ingestão excessiva de fitoestrógenos. O desenvolvimento puberal M2P1-2, os níveis hormonais e o US pélvico eram compatíveis com puberdade precoce periférica. Durante o seguimento, observou-se ingestão diária de alimentos baseados em soja (> 40 mg fitoestrógenos/dia). Soja contém fitoestrógenos, principalmente genisteína e daidzeína. Embora menos potentes do que o estradiol, sua concentração pode ser 13.000 a 22.000 vezes maior em crianças alimentadas somente com fórmulas baseadas em soja. Os pais foram aconselhados a reduzir para uma vez na semana o seu fornecimento na dieta. O desenvolvimento puberal cessou em M2-3P1 e a paciente, com 8,66 anos, continua a desenvolver-se com idades óssea e cronológica equivalentes. Questões relacionadas à segurança alimentar, principalmente de alimentos baseados em soja, permanecem sem respostas precisas. Embora sejam conhecidas as etiologias da puberdade precoce não progressiva e da telarca prematura, neste caso esteve fortemente relacionada à ingestão excessiva de soja e de outros alimentos ricos em fitoestrógenos que poderiam ter desencadeado a telarca atuando como desreguladores endócrinos.


Precocious thelarche is the breast development before 8 years of age with two peaks of incidence during the first two years of life and after 6 years of age. A 4.75-year-old girl presented with thelarche associated to an excessive intake of phytoestrogens (phye). Tanner development B2P1-2, hormonal levels and pelvic US were compatible with peripheral precocious puberty. During follow-up, a daily intake of soy-based foods was observed (> 40 mg phye/day). Soy is rich in phytoestrogens, mainly genistein and daidzein. Although phye are less strong than estradiol, its concentration could be from 13,000 to 22,000 times stronger in children fed only by soy-based formulas. Parents were advised and soy intake was reduced to once a week. Progression of pubertal development ceased at B2-3P1. The patient, now 8.66 years old, keeps growing with similar bone and chronological ages. Some questions related to industrial food security, mainly the soy-based food, remain without precise answer. Although it is well known the entity of non-progressive precocious puberty and premature thelarche, pubertal development in this case was strongly related to excessive daily intake of soy and other phye-rich food that could trigger puberty as endocrine disruptor.


Asunto(s)
Preescolar , Femenino , Humanos , Mama/crecimiento & desarrollo , Fitoestrógenos/efectos adversos , Pubertad Precoz/inducido químicamente , Alimentos de Soja/efectos adversos , Mama/efectos de los fármacos , Disruptores Endocrinos/efectos adversos , Fitoestrógenos/administración & dosificación , Glycine max
14.
Pediatr. aten. prim ; 8(32): 621-626, oct.-dic. 2006. tab
Artículo en Español | IBECS | ID: ibc-142721

RESUMEN

La telarquia precoz puede ser una patología benigna sin trascendencia clínica o el inicio de una pubertad precoz verdadera. En este artículo intentamos repasar las diferentes causas de la pubertad precoz, haciendo hincapié en las causas tumorales del sistema nervioso central como etiología de este cuadro, sobre todo, desde la introducción de técnicas de imagen como la resonancia magnética. En el caso clínico que presentamos llama la atención la edad tan temprana a la que se desarrolla la pubertad y cómo en estos casos es obligatorio descartar siempre una etiología tumoral; el hamartoma de hipotálamo es una de las causas más frecuente (AU)


The precocious thelarche can be either a benign condition without clinical significance or the beginning of a real precocious puberty. We try to revise, in this article, the different causes of precocious puberty, emphasizing the tumours of the central nervous system as the aetiology of this condition, especially after the introduction of image techniques as the magnetic resonance. In the clinical case we present, it is remarkable the early age the puberty is developed. In these cases, it is always obligatory to rule out the tumour aetiology being the hypothalamus hamartoma one of the most frequent causes (AU)


Asunto(s)
Femenino , Humanos , Lactante , Pubertad Precoz/etiología , Mama/crecimiento & desarrollo , Hamartoma/diagnóstico , Hipotálamo/anomalías , Hormona Liberadora de Gonadotropina , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormona Luteinizante , Hormona Folículo Estimulante , Espectroscopía de Resonancia Magnética
15.
Minerva Med ; 97(3): 277-85, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16855522

RESUMEN

Premature thelarche is usually considered a benign condition that disappears without influencing statural growth nor the timing of puberty. It is generally held a phenomenon of endogenous origin but exposure to oestrogenic pollutants must also be taken into consideration since environmental and epidemiological studies have shown that humans and some animal species are adversely affected by environmental chemical substances that interfere with the endocrine system and are known as endocrine disrupters. Environmental pollutants acting as endocrine disrupters include oestrogens and oestrogen-like products that are universally present in the form of hormones used in stockbreeding, chemicals employed in industry and agriculture, and substances naturally contained in plants and cereals. So far few studies have examined the influence of exogenous oestrogenic or oestrogen-like substances in premature thelarche, and there have been equally few reports of the occurrence of many cases in a circumscribed environment and a limited period of time. Since many agents are in a position to make a contribution to the biological mechanisms underlying thelarche, there is no easy way of determining the role of a given substance in the onset of the clinical picture. Furthermore, it must not be forgotten that both the metabolic clearance rate and the serum levels of oestradiol in healthy prepubertal children are still uncertain and even very low doses of exogenous steroid hormones might thus have significant biological effects. Aim of the work is to underline the importance of the exposure to oestrogenic environmental pollutants as possible cause of premature thelarche.


Asunto(s)
Enfermedades de la Mama/inducido químicamente , Mama/efectos de los fármacos , Disruptores Endocrinos/toxicidad , Mama/crecimiento & desarrollo , Niño , Estrógenos/toxicidad , Femenino , Humanos , Plaguicidas/toxicidad , Fenoles/toxicidad , Fitoestrógenos/toxicidad , Testosterona/toxicidad
18.
In Vitro Cell Dev Biol ; 25(7): 643-9, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2753852

RESUMEN

In experimental animal models the susceptibility of the mammary gland to neoplastic transformation is related to its degree of development and proliferative activity; this observation led us to determine whether the human breast epithelium also exhibits development-related differences, and whether these differences could be detected in an in vitro system. Normal breast tissue obtained from reduction mammoplasties of 9 patients ranging in age from 18 to 56 years were characterized in both whole mount preparations and organoids obtained after collagenase-hyaluronidase digestion by their degree of development based upon the types of lobules present. Lobules were classified into type 1 (Lob 1), composed of approximately 11 alveolar buds, the less developed; lobules type 2 (Lob 2), of moderate development, composed of approximately 47 ductules each, and lobules type 3 (Lob 3), composed of 80 ductules each, represented the highest level of development. Epithelial organoids obtained after digestion were plated in DMEM:F12 medium supplemented with hydrocortisone, cholera toxin, insulin and 5% horse serum with a calcium concentration of 1.05 mM Ca++. Following attachment, the medium was replaced by medium containing 0.040 mM Ca++. The percentage of attachment of organoids to the flask was greater in cells from Lob 1 (89-99%) and Lob 1+2 (79-100%) than in cells from Lob 3, which had a 53-67% attachment. The total yield of cells after 7 weeks in culture was also greater in cells derived from Lob 1 and Lob 1+2 than in cells from Lob 3. The total yield of cells obtained from primary cultures was not related to the number of organoids plated, but to the degree of development of the gland. The DNA-labeling index (DNA-LI) in intact breast tissue correlated with that in primary cultures; it was greater in Lob 1 and Lob 1+2 than in Lob 3. By flow cytometry, the highest percentage of cells in S-phase was seen in cells with the highest DNA-LI. We concluded that the growth characteristics of mammary epithelial cells in vitro in a low Ca++ medium is modulated by the degree of development and differentiation of the gland.


Asunto(s)
Mama/crecimiento & desarrollo , Adulto , Mama/anatomía & histología , Mama/metabolismo , Calcio/farmacología , División Celular , ADN/biosíntesis , Células Epiteliales , Femenino , Humanos , Persona de Mediana Edad , Técnicas de Cultivo de Órganos , Factores de Tiempo
19.
Prog Clin Biol Res ; 70: 171-82, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7198259

RESUMEN

The mammary glands are a uniquely designed extension of the mucosal immune systems of the gut and bronchus. The soluble and cellular products of lactation, in which immunologic selectivity and specificity exist, link the suckling neonate irrevocably to the immunologic and infectious experience of its mother. The immune competence of the breast and products of lactation are actively and constantly in flux, dependent on the mother's hormonal, environmental, and immunologic milieu. Most of the recent human investigation has focused primarily on milk immunoglobulin specificity. More work needs to be done on the role of passively transferred cellular products, the antiviral, antiprotozoan, and antitumor capabilities of milk, and on the mechanisms by which maternal immunizations or infections may influence the outcome of host-pathogen interactions in the suckling neonate.


Asunto(s)
Lactancia Materna , Inmunidad , Recién Nacido , Leche Humana/inmunología , Animales , Mama/crecimiento & desarrollo , Mama/inmunología , Calostro/inmunología , Femenino , Hormonas/fisiología , Humanos , Inmunidad Celular , Inmunoglobulina A Secretora/fisiología , Inmunoglobulinas/fisiología , Lactancia , Linfocitos/fisiología , Macrófagos/fisiología , Embarazo
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