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1.
Eur J Nutr ; 55 Suppl 1: S1-10, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26983608

ABSTRACT

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.


Subject(s)
Cardiovascular Diseases/prevention & control , Diet/standards , Fatty Acids, Omega-3/administration & dosage , Recommended Dietary Allowances , Evidence-Based Medicine , Humans , Reference Values
2.
Acta Hortic ; 841: 237-242, 2009.
Article in English | MEDLINE | ID: mdl-20396589

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-18024478

ABSTRACT

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.


Subject(s)
Alprostadil/analogs & derivatives , Apoptosis/drug effects , Colon/physiology , Colonic Neoplasms/prevention & control , Dinoprostone/antagonists & inhibitors , Fish Oils/pharmacology , Intestinal Mucosa/physiology , PPAR delta/antagonists & inhibitors , Pectins/pharmacology , Alprostadil/metabolism , Animals , Colon/cytology , Colon/drug effects , Colon/radiation effects , Dietary Fats , Intestinal Mucosa/cytology , Intestinal Mucosa/drug effects , Intestinal Mucosa/radiation effects , Male , Neoplasms, Radiation-Induced/prevention & control , Rats , Rats, Sprague-Dawley
4.
Am J Clin Dermatol ; 2(5): 291-303, 2001.
Article in English | MEDLINE | ID: mdl-11721648

ABSTRACT

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.


Subject(s)
Laser Therapy/methods , Skin Diseases/surgery , Forecasting , Humans , Laser Therapy/instrumentation , Laser Therapy/trends , Pigmentation Disorders/surgery , Skin Diseases, Vascular/surgery
5.
Carcinogenesis ; 22(11): 1831-5, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11698346

ABSTRACT

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.


Subject(s)
Adenocarcinoma/pathology , Azoxymethane/pharmacology , Carcinogens/pharmacology , Colonic Neoplasms/pathology , DNA Damage/drug effects , DNA, Neoplasm/drug effects , Adenocarcinoma/chemically induced , Adenocarcinoma/enzymology , Animals , Apoptosis/drug effects , Colonic Neoplasms/chemically induced , Colonic Neoplasms/enzymology , DNA Adducts , DNA Repair/drug effects , Immunoenzyme Techniques , Lipid Metabolism , Male , Methylation , O(6)-Methylguanine-DNA Methyltransferase/metabolism , Rats , Rats, Sprague-Dawley
6.
Dermatol Clin ; 19(3): 453-66, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11599402

ABSTRACT

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.


Subject(s)
Laser Therapy , Rhytidoplasty , Anesthesia , Cicatrix/surgery , Erbium , Humans , Laser Therapy/adverse effects , Laser Therapy/instrumentation , Laser Therapy/methods , Postoperative Care , Preoperative Care , Rhytidoplasty/adverse effects , Rhytidoplasty/instrumentation , Rhytidoplasty/methods , Skin/pathology , Skin Aging
7.
Am J Physiol Cell Physiol ; 280(5): C1066-75, 2001 May.
Article in English | MEDLINE | ID: mdl-11287318

ABSTRACT

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.


Subject(s)
Alkyl and Aryl Transferases/metabolism , Cell Transformation, Neoplastic , Docosahexaenoic Acids/pharmacology , Fatty Acids, Omega-3/pharmacology , Fatty Acids, Unsaturated/pharmacology , Genes, ras/drug effects , Linoleic Acid/pharmacology , Oncogene Protein p21(ras)/metabolism , Animals , Cell Division/drug effects , Cell Division/physiology , Cell Line, Transformed , Cell Membrane/drug effects , Cell Membrane/metabolism , Cell Survival/drug effects , Cells, Cultured , Colon , Corn Oil , Enzyme Activation , Fatty Acids, Omega-6 , Fish Oils , Membrane Lipids/metabolism , Mice , Oncogene Protein p21(ras)/genetics , Palmitic Acid/metabolism , Phospholipids/metabolism , Protein Processing, Post-Translational/drug effects , Rats , Signal Transduction/drug effects
8.
Clin Plast Surg ; 28(1): 37-52, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11248868
9.
Cutis ; 66(5): 390-2, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11107527

ABSTRACT

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.


Subject(s)
Granuloma Annulare/pathology , Sarcoidosis/pathology , Skin Diseases/pathology , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/therapeutic use , Biopsy , Female , Follow-Up Studies , Granuloma Annulare/complications , Humans , Middle Aged , Prednisone/administration & dosage , Prednisone/therapeutic use , Sarcoidosis/drug therapy , Sarcoidosis/etiology , Sarcoidosis, Pulmonary/complications , Sarcoidosis, Pulmonary/drug therapy , Skin/pathology , Skin Diseases/drug therapy , Skin Diseases/etiology , Time Factors
12.
Lasers Surg Med ; 27(4): 358-61, 2000.
Article in English | MEDLINE | ID: mdl-11074513

ABSTRACT

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.


Subject(s)
Laser Therapy , Lasers/adverse effects , Pigmentation Disorders/etiology , Pigmentation Disorders/therapy , Tattooing , Adult , Chemexfoliation , Female , Ferric Compounds , Humans , Time Factors
13.
J Am Acad Dermatol ; 43(5 Pt 2): 895-7, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11044814

ABSTRACT

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.


Subject(s)
Hamartoma/complications , Neurofibromatoses/complications , Scalp , Skin Neoplasms/complications , Facial Asymmetry/complications , Hamartoma/pathology , Humans , Male , Middle Aged , Neoplasms, Multiple Primary , Neurofibromatoses/pathology , Skin/pathology , Skin Neoplasms/pathology
14.
J Am Acad Dermatol ; 43(5 Pt 2): 908-12, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11044819

ABSTRACT

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.


Subject(s)
Dermatomyositis/pathology , Pityriasis Rubra Pilaris/pathology , Porokeratosis/pathology , Dermatomyositis/complications , Female , Humans , Middle Aged , Porokeratosis/complications , Skin/pathology
15.
Cancer Epidemiol Biomarkers Prev ; 9(8): 819-26, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10952099

ABSTRACT

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.


Subject(s)
Anticarcinogenic Agents/pharmacology , Colonic Neoplasms/prevention & control , DNA Adducts/drug effects , Fish Oils/pharmacology , Analysis of Variance , Animals , Apoptosis/drug effects , Colonic Neoplasms/chemically induced , Colonic Neoplasms/genetics , DNA Adducts/biosynthesis , DNA Adducts/chemistry , DNA Damage/drug effects , DNA Repair/drug effects , Guanine/analogs & derivatives , Guanine/metabolism , Intestinal Mucosa/cytology , Intestinal Mucosa/metabolism , Likelihood Functions , Male , Rats , Rats, Sprague-Dawley , Statistics, Nonparametric , tRNA Methyltransferases/biosynthesis
17.
Carcinogenesis ; 21(8): 1513-9, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10910952

ABSTRACT

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.


Subject(s)
Apoptosis/physiology , Colon/cytology , Colon/enzymology , Diet , Isoenzymes/biosynthesis , Protein Kinase C/biosynthesis , Animals , Apoptosis/drug effects , Azoxymethane , Carcinogens , Cell Cycle/drug effects , Cell Cycle/physiology , Cell Division/physiology , Cellulose/pharmacology , Colon/drug effects , Colonic Neoplasms/chemically induced , Colonic Neoplasms/enzymology , Colonic Neoplasms/pathology , Corn Oil/pharmacology , Fatty Acids, Omega-3/pharmacology , Immunohistochemistry , Male , Pectins/pharmacology , Precancerous Conditions/chemically induced , Precancerous Conditions/enzymology , Precancerous Conditions/pathology , Protein Kinase C beta , Rats , Rats, Sprague-Dawley , Subcellular Fractions/enzymology
18.
Toxicol Lett ; 112-113: 411-4, 2000 Mar 15.
Article in English | MEDLINE | ID: mdl-10720760

ABSTRACT

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.


Subject(s)
Apoptosis/drug effects , Butyrates/therapeutic use , Colonic Neoplasms/prevention & control , Diet , Animals , Drug Interactions , Mice , Molecular Biology , Signal Transduction/drug effects , Tumor Cells, Cultured
19.
Dermatol Surg ; 26(2): 135-7, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10691942

ABSTRACT

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.


Subject(s)
Biocompatible Materials/adverse effects , Drug Hypersensitivity/etiology , Hyaluronic Acid/adverse effects , Skin Diseases/chemically induced , Acute Disease , Biocompatible Materials/administration & dosage , Combined Modality Therapy , Drug Hypersensitivity/diagnosis , Drug Hypersensitivity/therapy , Female , Gels , Humans , Hyaluronic Acid/administration & dosage , Injections, Intradermal , Middle Aged , Recurrence , Skin Aging/drug effects , Skin Diseases/diagnosis , Skin Diseases/therapy
20.
Cell Growth Differ ; 10(11): 749-58, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10593651

ABSTRACT

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.


Subject(s)
Apoptosis/drug effects , Azoxymethane/pharmacology , Carcinogens/pharmacology , DNA Methylation , DNA Repair/drug effects , Alkyl and Aryl Transferases/metabolism , Alkylation , Animals , Cell Compartmentation/drug effects , Cell Compartmentation/genetics , Cell Division/drug effects , Cell Division/genetics , Cells, Cultured , Colon/cytology , DNA/analysis , DNA/metabolism , DNA Damage , Male , Rats , Rats, Sprague-Dawley , Stem Cells/cytology , Stem Cells/drug effects , Stem Cells/enzymology
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