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1.
Eur J Nutr ; 55 Suppl 1: S1-10, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26983608

RESUMEN

Nutrition is complex-and seemingly getting more complicated. Most consumers are familiar with "essential nutrients," e.g., vitamins and minerals, and more recently protein and important amino acids. These essential nutrients have nutrient reference values, referred to as dietary reference intakes (DRIs) developed by consensus committees of scientific experts convened by the Institute of Medicine of the National Academy of Sciences, Engineering, and Medicine and carried out by the Food and Nutrition Board. The DRIs comprise a set of four nutrient-based reverence values, the estimated average requirements, the recommended dietary allowances (RDAs), the adequate intakes and the tolerable upper intake levels for micronutrient intakes and an acceptable macronutrient distribution range for macronutrient intakes. From the RDA, the US Food and Drug Administration (FDA) derives a labeling value called the daily value (DV), which appears on the nutrition label of all foods for sale in the US. The DRI reports do not make recommendations about whether the DV labeling values can be set only for what have been defined to date as "essential nutrients." For example, the FDA set a labeling value for "dietary fiber" without having the DV. Nutrient reference values-requirements are set by Codex Alimentarius for essential nutrients, and regulatory bodies in many countries use these Codex values in setting national policy for recommended dietary intakes. However, the focus of this conference is not on essential nutrients, but on the "nonessential nutrients," also termed dietary bioactive components. They can be defined as "Constituents in foods or dietary supplements, other than those needed to meet basic human nutritional needs, which are responsible for changes in health status (Office of Disease Prevention and Health Promotion, Office of Public Health and Science, Department of Health and Human Services in Fed Regist 69:55821-55822, 2004)." Substantial and often persuasive scientific evidence does exist to confirm a relationship between the intake of a specific bioactive constituent and enhanced health conditions or reduced risk of a chronic disease. Further, research on the putative mechanisms of action of various classes of bioactives is supported by national and pan-national government agencies, and academic institutions, as well as functional food and dietary supplement manufacturers. Consumers are becoming educated and are seeking to purchase products containing bioactives, yet there is no evaluative process in place to let the public know how strong the science is behind the benefits or the quantitative amounts needed to achieve these beneficial health effects or to avoid exceeding the upper level (UL). When one lacks an essential nutrient, overt deficiency with concomitant physiological determents and eventually death are expected. The absence of bioactive substances from the diet results in suboptimal health, e.g., poor cellular and/or physiological function, which is relative and not absolute. Regrettably at this time, there is no DRI process to evaluate bioactives, although a recent workshop convened by the National Institutes of Health (Options for Consideration of Chronic Disease Endpoints for Dietary Reference Intakes (DRIs); March 10-11, 2015; http://health.gov/dietaryguidelines/dri/ ) did explore the process to develop DVs for nutrients, the lack of which result in increased risk of chronic disease (non-communicable disease) endpoints. A final report is expected soon. This conference (CRN-International Scientific Symposium; "Nutrient Reference Value-Non-Communicable Disease (NRV-NCD) Endpoints," 20 November in Kronberg, Germany; http://www.crn-i.ch/2015symposium/ ) explores concepts related to the Codex NRV process, the public health opportunities in setting NRVs for bioactive constituents, and further research and details on the specific class of bioactives, n-3 long-chain polyunsaturated fatty acids (also termed omega-3 fatty acids) and their constituents, specifically docosahexaenoic acid and eicosapentaenoic acid.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Dieta/normas , Ácidos Grasos Omega-3/administración & dosificación , Ingesta Diaria Recomendada , Medicina Basada en la Evidencia , Humanos , Valores de Referencia
2.
Acta Hortic ; 841: 237-242, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20396589

RESUMEN

We have demonstrated that 0.45% quercetin added to a diet containing corn oil (15% w/w), as the lipid source, and cellulose (6% w/w), as the fiber source, was able to suppress the formation of high multiplicity aberrant crypt foci (ACF > 4 AC/focus), to lower proliferation and enhance apoptosis in a rat model of colon cancer. This experiment determined whether quercetin was acting as an antiinflammatory molecule in an in vivo model of colon cancer. We used weanling (21 d old) Sprague Dawley rats (n = 40) in a 2×2 factorial experiment to determine the influence of quercetin on iNOS, COX-1 and COX-2 expressions, all of which are elevated in colon cancer. Half of the rats received a diet containing either 0 or 0.45% quercetin, and within each diet group, half of the rats were injected with saline or azoxymethane (AOM, 15 mg/kg BW, sc, 2× during wk 3 and 4). The colon was resected 4 wk after the last AOM injection, and the mucosa scraped and processed for RNA isolation. Data from this experiment were analyzed using a mixed model in SAS for main effects and their interaction. AOM injection stimulated (P < 0.0001) iNOS expression. However there was an interaction such that, relative to rats injected with saline, AOM-injected rats consuming diets without quercetin had significantly elevated iNOS expression (5.29-fold), but the expression in AOM-injected rats consuming the diet with quercetin was not significantly elevated (1.68-fold). COX-1 expression was 20.2% lower (P < 0.06) in rats consuming diets containing quercetin. COX-2 expression was 24.3% higher (P < 0.058) in rats consuming diets without quercetin. These data suggest inflammatory processes are elevated in this early stage of colon carcinogenesis, yet quercetin may protect against colon carcinogenesis by down-regulating the expressions of COX-1 and COX-2.

3.
Carcinogenesis ; 29(4): 790-6, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18024478

RESUMEN

We have shown that dietary fish oil and pectin (FP) protects against radiation-enhanced colon cancer by upregulating apoptosis in colonic mucosa. To investigate the mechanism of action, we provided rats (n = 40) with diets containing the combination of FP or corn oil and cellulose (CC) prior to exposure to 1 Gy, 1 GeV/nucleon Fe-ion. All rats were injected with a colon-specific carcinogen, azoxymethane (AOM; 15 mg/kg), 10 and 17 days after irradiation. Levels of colonocyte apoptosis, prostaglandin E(2) (PGE(2)), PGE(3), microsomal prostaglandin E synthase-2 (mPGES-2), total beta-catenin, nuclear beta-catenin staining (%) and peroxisome proliferator-activated receptor delta (PPARdelta) expression were quantified 31 weeks after the last AOM injection. FP induced a higher (P < 0.01) apoptotic index in both treatment groups, which was associated with suppression (P < 0.05) of antiapoptotic mediators in the cyclooxygenase (COX) pathway (mPGES-2 and PGE(2)) and the Wnt/beta-catenin pathway [total beta-catenin and nuclear beta-catenin staining (%); P < 0.01] compared with the CC diet. Downregulation of COX and Wnt/beta-catenin pathways was associated with a concurrent suppression (P < 0.05) of PPARdelta levels in FP-fed rats. In addition, colonic mucosa from FP animals contained (P < 0.05) a proapoptotic, eicosapentaenoic acid-derived COX metabolite, PGE(3). These results indicate that FP enhances colonocyte apoptosis in AOM-alone and irradiated AOM rats, in part through the suppression of PPARdelta and PGE(2) and elevation of PGE(3). These data suggest that the dietary FP combination may be used as a possible countermeasure to colon carcinogenesis, as apoptosis is enhanced even when colonocytes are exposed to radiation and/or an alkylating agent.


Asunto(s)
Alprostadil/análogos & derivados , Apoptosis/efectos de los fármacos , Colon/fisiología , Neoplasias del Colon/prevención & control , Dinoprostona/antagonistas & inhibidores , Aceites de Pescado/farmacología , Mucosa Intestinal/fisiología , PPAR delta/antagonistas & inhibidores , Pectinas/farmacología , Alprostadil/metabolismo , Animales , Colon/citología , Colon/efectos de los fármacos , Colon/efectos de la radiación , Grasas de la Dieta , Mucosa Intestinal/citología , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/efectos de la radiación , Masculino , Neoplasias Inducidas por Radiación/prevención & control , Ratas , Ratas Sprague-Dawley
4.
Am J Clin Dermatol ; 2(5): 291-303, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11721648

RESUMEN

Advances in laser technology have been so marked over the past two decades that successful eradication of many cutaneous pathologies and congenital defects, including vascular and pigmented lesions, tattoos, scars, and unwanted hair, can now be fully realized. Because of the relative ease with which many of these lesions can be removed, coupled with a low incidence of adverse postoperative sequelae, demand for laser surgery has increased substantially. In this review, the currently available laser systems with cutaneous application are outlined, with special reference to recent advancements and modifications in laser technology that have greatly expanded the laser surgeon's armamentarium and improved upon overall treatment efficacy.


Asunto(s)
Terapia por Láser/métodos , Enfermedades de la Piel/cirugía , Predicción , Humanos , Terapia por Láser/instrumentación , Terapia por Láser/tendencias , Trastornos de la Pigmentación/cirugía , Enfermedades Cutáneas Vasculares/cirugía
5.
Carcinogenesis ; 22(11): 1831-5, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11698346

RESUMEN

There is now general agreement that the etiology of proximal and distal colon cancers may differ, thus prompting renewed interest in understanding anatomical site-specific molecular mechanisms of tumor development. Using a 2x2x2 factorial design with male Sprague-Dawley rats (corn oil, fish oil; pectin, cellulose; plus or minus azoxymethane injection) we found a greater than 2-fold difference (P < 0.001) in tumor incidence proximally versus distally (prox/dist ratio: corn oil, 2.25; fish oil, 2.61). The purpose of the present study was to determine if the higher degree of proximal versus distal tumors in our model system could be accounted for by differences between these two sites in initial DNA damage, response to that damage or an effect of diet at one site but not the other. DNA damage was assessed by quantitative immunohistochemistry of O(6)-methylguanine adducts; repair by measurement of O(6)-methylguanine-DNA alkyltransferase and removal was determined by measurement of targeted apoptosis. Although overall initial DNA damage was similar at both sites, in the distal colon there was a greater expression of repair protein (P < 0.001) and a greater degree of targeted apoptosis (P < 0.0001). There was also a reduction in DNA damage in the distal colon of rats consuming fish oil. Together, these results suggest that the lower tumor incidence in the distal colon may be a result of the capacity to deal with initial DNA damage by the distal colon, as compared with the proximal colon. Therefore, the determination of site-specific mechanisms in tumor development is important because distinct strategies may be required to protect against cancer at different sites.


Asunto(s)
Adenocarcinoma/patología , Azoximetano/farmacología , Carcinógenos/farmacología , Neoplasias del Colon/patología , Daño del ADN/efectos de los fármacos , ADN de Neoplasias/efectos de los fármacos , Adenocarcinoma/inducido químicamente , Adenocarcinoma/enzimología , Animales , Apoptosis/efectos de los fármacos , Neoplasias del Colon/inducido químicamente , Neoplasias del Colon/enzimología , Aductos de ADN , Reparación del ADN/efectos de los fármacos , Técnicas para Inmunoenzimas , Metabolismo de los Lípidos , Masculino , Metilación , O(6)-Metilguanina-ADN Metiltransferasa/metabolismo , Ratas , Ratas Sprague-Dawley
6.
Dermatol Clin ; 19(3): 453-66, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11599402

RESUMEN

The short-pulsed Er:YAG laser system is an excellent ablative tool for cutaneous resurfacing. This system is most efficacious for patients with milder cutaneous involvement, including mild photoinduced facial rhytides, mildly atrophic scars, and textural changes caused by fibrosis and dermatochalasis. The Er:YAG laser cannot achieve the same dramatic clinical and histologic improvements produced with the CO2 laser but does offer some distinct advantages that make it a valuable addition to the laser surgeon's armamentarium. The Er:YAG laser, because of its higher affinity for water-containing tissues, effects a much finer level of tissue ablation. Although erbium laser resurfacing results in decreased postoperative morbidity with a shorter recovery period, it cannot effect the same degree of improvement in photodamaged skin as can the CO2 laser. Excellent results, however, can be achieved with this laser, up to 50% or more overall clinical improvement, in patients with milder photodamage and scarring (Glogau classes I and II). In darker-skinned patients, the Er:YAG laser is often the preferred treatment modality. Continued research in the field has already led to the development of longer-pulsed Er:YAG lasers, which offer a compromise between the CO2 laser and the short-pulsed Er:YAG lasers in terms of clinical benefits while maintaining the safety profile of the traditional short-pulsed system. In addition, many surgeons now use a combination approach with the CO2 and Er:YAG lasers in an effort to maximize collagen contraction in certain areas and limit postoperative morbidity. As more research is conducted within the field of cutaneous resurfacing, newer systems will be developed in the continuing effort to create the ideal laser system--one which ameliorates the signs of photoaging without risk of major side effects or significant postoperative recovery.


Asunto(s)
Terapia por Láser , Ritidoplastia , Anestesia , Cicatriz/cirugía , Erbio , Humanos , Terapia por Láser/efectos adversos , Terapia por Láser/instrumentación , Terapia por Láser/métodos , Cuidados Posoperatorios , Cuidados Preoperatorios , Ritidoplastia/efectos adversos , Ritidoplastia/instrumentación , Ritidoplastia/métodos , Piel/patología , Envejecimiento de la Piel
7.
Am J Physiol Cell Physiol ; 280(5): C1066-75, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11287318

RESUMEN

Ras proteins are critical regulators of cell function, including growth, differentiation, and apoptosis, with membrane localization of the protein being a prerequisite for malignant transformation. We have recently demonstrated that feeding fish oil, compared with corn oil, decreases colonic Ras membrane localization and reduces tumor formation in rats injected with a colon carcinogen. Because the biological activity of Ras is regulated by posttranslational lipid attachment and its interaction with stimulatory lipids, we investigated whether docosahexaenoic acid (DHA), found in fish oil, compared with linoleic acid (LA), found in corn oil, alters Ras posttranslational processing, activation, and effector protein function in young adult mouse colon cells overexpressing H-ras (YAMC-ras). We show here that the major n-3 polyunsaturated fatty acid (PUFA) constituent of fish oil, DHA, compared with LA (an n-6 PUFA), reduces Ras localization to the plasma membrane without affecting posttranslational lipidation and lowers GTP binding and downstream p42/44(ERK)-dependent signaling. In view of the central role of oncogenic Ras in the development of colon cancer, the finding that n-3 and n-6 PUFA differentially modulate Ras activation may partly explain why dietary fish oil protects against colon cancer development.


Asunto(s)
Transferasas Alquil y Aril/metabolismo , Transformación Celular Neoplásica , Ácidos Docosahexaenoicos/farmacología , Ácidos Grasos Omega-3/farmacología , Ácidos Grasos Insaturados/farmacología , Genes ras/efectos de los fármacos , Ácido Linoleico/farmacología , Proteína Oncogénica p21(ras)/metabolismo , Animales , División Celular/efectos de los fármacos , División Celular/fisiología , Línea Celular Transformada , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Colon , Aceite de Maíz , Activación Enzimática , Ácidos Grasos Omega-6 , Aceites de Pescado , Lípidos de la Membrana/metabolismo , Ratones , Proteína Oncogénica p21(ras)/genética , Ácido Palmítico/metabolismo , Fosfolípidos/metabolismo , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Ratas , Transducción de Señal/efectos de los fármacos
9.
Cutis ; 66(5): 390-2, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11107527

RESUMEN

We report the unique case of a 50-year-old African American female with pulmonary sarcoidosis who presented with a new ichthyosiform eruption symmetrically located on the anterior shins and surrounded by red, translucent, intradermal papules. A skin biopsy of a new red papule showed features consistent with granuloma annulare (GA) with positive mucin staining, and an older hyperpigmented papule showed classic dermal noncaseating granulomas consistent with sarcoidosis. Recent reports have clearly demonstrated GA occurring in association with sarcoidosis, but this is the first report that suggests that a GA lesion may develop into a sarcoidal granuloma. We propose that GA may act as a precursor lesion to the more mature sarcoidal granuloma. This case further underscores the importance of careful clinicopathologic correlation.


Asunto(s)
Granuloma Anular/patología , Sarcoidosis/patología , Enfermedades de la Piel/patología , Antiinflamatorios/administración & dosificación , Antiinflamatorios/uso terapéutico , Biopsia , Femenino , Estudios de Seguimiento , Granuloma Anular/complicaciones , Humanos , Persona de Mediana Edad , Prednisona/administración & dosificación , Prednisona/uso terapéutico , Sarcoidosis/tratamiento farmacológico , Sarcoidosis/etiología , Sarcoidosis Pulmonar/complicaciones , Sarcoidosis Pulmonar/tratamiento farmacológico , Piel/patología , Enfermedades de la Piel/tratamiento farmacológico , Enfermedades de la Piel/etiología , Factores de Tiempo
12.
Lasers Surg Med ; 27(4): 358-61, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11074513

RESUMEN

BACKGROUND AND OBJECTIVE: Cosmetic tattoo removal has a reported risk of immediate pigment darkening when treated with a high energy, nanosecond pulsed-laser system. Surgical treatment options for this reaction are limited and carry significant risk of scarring and permanent pigment alterations. This report describes the response of a resistant Q-switched ruby laser-induced cosmetic tattoo ink darkening to multiple treatments with the Q-switched alexandrite laser and Q-switch Nd:YAG laser and textural improvement with the UltraPulse CO(2) laser. STUDY DESIGN/MATERIALS AND METHODS: A woman with Q-switched ruby laser-induced pigment darkening of a cosmetic tattoo of the upper lip resistant to four further treatments with the ruby laser and two chemical peels received a total of 26 treatments with the Q-switched alexandrite and Nd:YAG lasers and a single treatment with the UltraPulse CO(2) laser, most treatments being done at monthly intervals. RESULTS: Treatment of the affected areas with the Q-switched alexandrite and Nd:YAG lasers resulted in complete clearing of the pigment without scarring, but revealed some preexisting textural changes. Use of the UltraPulse CO(2) laser smoothed the surface irregularities. CONCLUSION: The Q-switched pigment lasers are a useful modality for treating this pigment darkening reaction. As in this case, multiple treatment sessions with the laser may be necessary but the pigment can be expected to clear eventually without scarring. Any textural changes may be blended with the UltraPulse CO(2) laser with further improvement.


Asunto(s)
Terapia por Láser , Rayos Láser/efectos adversos , Trastornos de la Pigmentación/etiología , Trastornos de la Pigmentación/terapia , Tatuaje , Adulto , Quimioexfoliación , Femenino , Compuestos Férricos , Humanos , Factores de Tiempo
13.
J Am Acad Dermatol ; 43(5 Pt 2): 895-7, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11044814

RESUMEN

We describe an unusual case involving the simultaneous occurrence of segmental neurofibromatosis (Type V NF) in a patient with a large nevus sebaceus of Jadassohn in the same physical distribution. Causative mechanisms of development of these 2 genetic disorders have not been definitively linked. Factors producing these diseases probably involve similar tissues at the same point in development because both have been reported in association with central nervous system anomalies and have been classified among the neurocutaneous syndromes. This is a case of a nevus sebaceus occurring in association with and in the same physical distribution as segmental NF. These disorders most likely represent a spectrum of disease within the phakomatoses.


Asunto(s)
Hamartoma/complicaciones , Neurofibromatosis/complicaciones , Cuero Cabelludo , Neoplasias Cutáneas/complicaciones , Asimetría Facial/complicaciones , Hamartoma/patología , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Primarias Múltiples , Neurofibromatosis/patología , Piel/patología , Neoplasias Cutáneas/patología
14.
J Am Acad Dermatol ; 43(5 Pt 2): 908-12, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11044819

RESUMEN

We describe a 53-year-old white woman with dermatomyositis (DM) who had additional clinical findings of pityriasis rubra pilaris (type Wong dermatomyositis) with histopathologic features of both pityriasis rubra pilaris (PRP) and porokeratosis. Type Wong dermatomyositis was originally described in 11 patients by Wong in 1969 and has been reported in 5 additional patients. This is a rarely described phenomenon in which patients with DM develop cutaneous hyperkeratotic lesions that resemble PRP and histologically show follicular hyperkeratosis and hair follicle destruction. Arrector pilorum muscles also show degenerative findings and myositis. We believe that this is the first reported case of a patient with type Wong DM who also has clinical and histologic features suggestive of porokeratosis. This is important because of the association of adult-onset dermatomyositis with internal malignancy and the well-documented association of porokeratosis with immunosuppression. These clinical and histologic findings serve as markers for malignancy in patients with DM. These patients warrant a complete review of systems and investigation for age-appropriate neoplasms as well as close long-term follow-up by dermatologists to ensure that these cutaneous eruptions are not overlooked.


Asunto(s)
Dermatomiositis/patología , Pitiriasis Rubra Pilaris/patología , Poroqueratosis/patología , Dermatomiositis/complicaciones , Femenino , Humanos , Persona de Mediana Edad , Poroqueratosis/complicaciones , Piel/patología
15.
Cancer Epidemiol Biomarkers Prev ; 9(8): 819-26, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10952099

RESUMEN

There is epidemiological, clinical, and experimental evidence that dietary fish oil, containing n-3 polyunsaturated fatty acids, protects against colon tumor development. However, its effects on colonocytes in vivo remain poorly understood. Therefore, we investigated the ability of fish oil to modulate colonic methylation-induced DNA damage, repair, and deletion. Sprague Dawley rats were provided with complete diets containing either corn oil or fish oil (15% by weight). Animals were injected with azoxymethane, and the distal colon was removed 3, 6, 9, or 12 h later. Targeted apoptosis and DNA damage were assessed by cell position within the crypt using the terminal deoxynucleotidyl transferase-mediated nick end labeling assay and quantitative immunohistochemical analysis of O6-methylguanine adducts, respectively. Localization and expression of the alkyl group acceptor, O6-methylguanine-DNA-methyltransferase, was also determined. Lower levels of adducts were detected at 6, 9, and 12 h in fish oil- versus corn oil-fed animals (P < 0.05). In addition, fish oil supplementation had the greatest effect on apoptosis in the top one-third of the crypt, increasing the apoptotic index compared with corn oil-fed rats (P < 0.05). In the top one-third of the crypt, fish oil feeding caused an incremental stimulation of apoptosis as adduct level increased. In contrast, a negative correlation between apoptosis and adduct incidence occurred with corn oil feeding (P < 0.05). Diet had no main effect (all tertiles combined) on O6-methylguanine-DNA-methyltransferase expression over the time frame of the experiment. The enhancement of targeted apoptosis combined with the reduced formation of O6-methylguanine adducts may account, in part, for the observed protective effect of n-3 polyunsaturated fatty acids against experimentally induced colon cancer.


Asunto(s)
Anticarcinógenos/farmacología , Neoplasias del Colon/prevención & control , Aductos de ADN/efectos de los fármacos , Aceites de Pescado/farmacología , Análisis de Varianza , Animales , Apoptosis/efectos de los fármacos , Neoplasias del Colon/inducido químicamente , Neoplasias del Colon/genética , Aductos de ADN/biosíntesis , Aductos de ADN/química , Daño del ADN/efectos de los fármacos , Reparación del ADN/efectos de los fármacos , Guanina/análogos & derivados , Guanina/metabolismo , Mucosa Intestinal/citología , Mucosa Intestinal/metabolismo , Funciones de Verosimilitud , Masculino , Ratas , Ratas Sprague-Dawley , Estadísticas no Paramétricas , ARNt Metiltransferasas/biosíntesis
17.
Carcinogenesis ; 21(8): 1513-9, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10910952

RESUMEN

We have recently demonstrated that overexpression of PKC beta(II) renders transgenic mice more susceptible to carcinogen-induced colonic hyperproliferation and aberrant crypt foci formation. In order to further investigate the ability of PKC beta(II) to modulate colonocyte cytokinetics, we determined the localization of PKC beta(II) with respect to cell proliferation and apoptosis along the entire colonic crypt axis following carcinogen and diet manipulation. Rats were provided diets containing either corn oil [containing n-6 polyunsaturated fatty acids (PUFA)] or fish oil (containing n-3 PUFA), cellulose (non-fermentable fiber) or pectin (fermentable fiber) and injected with azoxymethane (AOM) or saline. After 16 weeks, an intermediate time point when no macroscopic tumors are detected, colonic sections were utilized for immunohistochemical image analysis and immunoblotting. Cell proliferation was measured by incorporation of bromodeoxyuridine into DNA and apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling. In the distal colon, PKC beta(II) staining was localized to the upper portion of the crypt. In comparison, proximal crypts had more (P < 0.05) staining in the lower tertile. AOM enhanced (P < 0.05) PKC beta(II) expression in all regions of the distal colonic crypt (upper, middle and lower tertiles). There was also an interaction (P < 0.05) between dietary fat and fiber on PKC beta(II) expression (corn/pectin > fish/cellulose, fish/pectin > corn/cellulose) in all regions of the distal colonic crypt. With respect to colonic cell kinetics, proliferation paralleled the increase in PKC beta(II) expression in carcinogen-treated animals. In contrast, apoptosis at the lumenal surface was inversely proportional to PKC beta(II) expression in the upper tertile. These results suggest that an elevation in PKC beta(II) expression along the crypt axis in the distal colon is linked to enhancement of cell proliferation and suppression of apoptosis, predictive intermediate biomarkers of tumor development. Therefore, select dietary factors may confer protection against colon carcinogenesis in part by blocking carcinogen-induced PKC beta(II) expression.


Asunto(s)
Apoptosis/fisiología , Colon/citología , Colon/enzimología , Dieta , Isoenzimas/biosíntesis , Proteína Quinasa C/biosíntesis , Animales , Apoptosis/efectos de los fármacos , Azoximetano , Carcinógenos , Ciclo Celular/efectos de los fármacos , Ciclo Celular/fisiología , División Celular/fisiología , Celulosa/farmacología , Colon/efectos de los fármacos , Neoplasias del Colon/inducido químicamente , Neoplasias del Colon/enzimología , Neoplasias del Colon/patología , Aceite de Maíz/farmacología , Ácidos Grasos Omega-3/farmacología , Inmunohistoquímica , Masculino , Pectinas/farmacología , Lesiones Precancerosas/inducido químicamente , Lesiones Precancerosas/enzimología , Lesiones Precancerosas/patología , Proteína Quinasa C beta , Ratas , Ratas Sprague-Dawley , Fracciones Subcelulares/enzimología
18.
Toxicol Lett ; 112-113: 411-4, 2000 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-10720760

RESUMEN

Colon cancer evolves from a progressive inhibition of apoptosis and is influenced strongly by diet. Among dietary factors, butyrate (derived from fermentable fibers) may have utility as a chemopreventive agent because of its ability to promote apoptosis. Because CD95 (APO-1/Fas) transduces signals resulting in apoptosis, we tested the hypothesis that butyrate-dependent colonocyte apoptosis is mediated by this death receptor. Treatment of immortalized mouse colon cells with Fas agonistic antibody induced cell death, indicating that Fas in colonocytes is functional. Antagonism of Fas signaling using a soluble Fas:Fc chimera blocked butyrate induction of apoptosis. Therefore, Fas receptor dependent signal transduction is required for butyrate induction of apoptosis in colonic cells.


Asunto(s)
Apoptosis/efectos de los fármacos , Butiratos/uso terapéutico , Neoplasias del Colon/prevención & control , Dieta , Animales , Interacciones Farmacológicas , Ratones , Biología Molecular , Transducción de Señal/efectos de los fármacos , Células Tumorales Cultivadas
19.
Dermatol Surg ; 26(2): 135-7, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10691942

RESUMEN

BACKGROUND: Injectable hyaluronic acid gel is a non-animal biomaterial used for soft tissue augmentation. OBJECTIVE: The dermal implantation of this naturally occurring polysaccharide is reported to be well tolerated by patients, with a longer duration in tissue than bovine collagen without any major local or systemic side effects. We report a case of an acute hypersensitivity reaction in a woman after her third injection for improvement of melolabial fold wrinkles. METHODS: An adverse granulomatous-like response to the intradermal injection of a modified hyaluronic acid gel is described. RESULTS: The patient developed indurated and erythematous papulocystic nodules in the melolabial folds bilaterally at the sites of injection. CONCLUSION: Injectable hyaluronic acid gel can be associated with severe allergic reactions and patients should be warned of this possible treatment side effect.


Asunto(s)
Materiales Biocompatibles/efectos adversos , Hipersensibilidad a las Drogas/etiología , Ácido Hialurónico/efectos adversos , Enfermedades de la Piel/inducido químicamente , Enfermedad Aguda , Materiales Biocompatibles/administración & dosificación , Terapia Combinada , Hipersensibilidad a las Drogas/diagnóstico , Hipersensibilidad a las Drogas/terapia , Femenino , Geles , Humanos , Ácido Hialurónico/administración & dosificación , Inyecciones Intradérmicas , Persona de Mediana Edad , Recurrencia , Envejecimiento de la Piel/efectos de los fármacos , Enfermedades de la Piel/diagnóstico , Enfermedades de la Piel/terapia
20.
Cell Growth Differ ; 10(11): 749-58, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10593651

RESUMEN

DNA alkylating agent exposure results in the formation of a number of DNA adducts, with O6-methyl-deoxyguanosine (O6-medG) being the major mutagenic and cytotoxic DNA lesion. Critical to the prevention of colon cancer is the removal of O6-medG DNA adducts, either through repair, for example, by O6-alkylguanine-DNA alkyltransferase (ATase) or targeted apoptosis. We report how rat colonocytes respond to administration of azoxymethane (a well-characterized experimental colon carcinogen and DNA-methylating agent) in terms of O6-medG DNA adduct formation and adduct removal by ATase and apoptosis. Our results are: (a) DNA damage is greater in actively proliferating cells than in the differentiated cell compartment; (b) expression of the DNA repair enzyme ATase was not targeted to the proliferating cells or stem cells but rather is confined primarily to the upper portion of the crypt; (c) apoptosis is primarily targeted to the stem cell and proliferative compartments; and (d) the increase in DNA repair enzyme expression over time in the bottom one-third of the crypt corresponds with the decrease in apoptosis in this same crypt region.


Asunto(s)
Apoptosis/efectos de los fármacos , Azoximetano/farmacología , Carcinógenos/farmacología , Metilación de ADN , Reparación del ADN/efectos de los fármacos , Transferasas Alquil y Aril/metabolismo , Alquilación , Animales , Compartimento Celular/efectos de los fármacos , Compartimento Celular/genética , División Celular/efectos de los fármacos , División Celular/genética , Células Cultivadas , Colon/citología , ADN/análisis , ADN/metabolismo , Daño del ADN , Masculino , Ratas , Ratas Sprague-Dawley , Células Madre/citología , Células Madre/efectos de los fármacos , Células Madre/enzimología
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