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1.
J Infect Dis ; 229(Supplement_2): S188-S196, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-37820738

RESUMEN

BACKGROUND: Exposures associated with mpox infection remain imperfectly understood. METHODS: We conducted a case-control study enrolling participants who received molecular tests for mpox/orthopoxvirus in California from November 2022 through June 2023. We collected data on behaviors during a 21-day risk period before symptom onset or testing among mpox case patients and test-negative controls. RESULTS: Thirteen of 54 case patients (24.1%) and 5 of 117 controls (4.3%) reported sexual exposure to individuals they identified as potential mpox case patients ("index contacts"; odds ratio [OR], 7.7 [95% confidence interval (CI), 2.5-19.3] relative to individuals who did not report exposure to potential mpox case patients). Among these participants, 10 of 13 case patients (76.9%) and 2 of 5 controls (40.0%) reported that their index contacts were not experiencing symptoms visible to participants during sex (OR, 14.9 [95% CI, 3.6-101.8]). Only 3 of 54 case patients (5.6%) reported exposure to symptomatic index contacts. Case patients reported more anal/vaginal sex partners than did controls (adjusted OR, 2.2 [95% CI, 1.0-4.8] for 2-3 partners and 3.8 [1.7-8.8] for ≥4 partners). Male case patients with penile lesions more commonly reported insertive anal/vaginal sex than those without penile lesions (adjusted OR, 9.3 [95% CI, 1.6-54.8]). Case patients with anorectal lesions more commonly reported receptive anal sex than those without anorectal lesions (adjusted OR, 14.4 [95% CI, 1.0-207.3]). CONCLUSIONS: Sexual exposure to contacts known or suspected to have experienced mpox was associated with increased risk of infection, often when index contacts lacked apparent symptoms. Exposure to more sex partners, including those whom participants did not identify as index contacts, was associated with increased risk of infection in a site-specific manner. While participants' assessment of symptoms in partners may be imperfect, these findings suggest that individuals without visibly prominent mpox symptoms transmit infection.


Asunto(s)
Infecciones por VIH , Mpox , Minorías Sexuales y de Género , Femenino , Humanos , Masculino , Estudios de Casos y Controles , Factores de Riesgo , Conducta Sexual , California , Homosexualidad Masculina
2.
Rheumatology (Oxford) ; 62(5): 1860-1869, 2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-36135792

RESUMEN

OBJECTIVES: Cognitive dysfunction (CD) is a common manifestation of SLE that can have detrimental consequences for those affected. To date, no treatments have been approved for SLE-CD. This study aims to assess the association of azathioprine (AZA) and mycophenolate (MMF) use with SLE-CD, given that these medications have demonstrated neuroprotective qualities in prior studies. METHODS: Consecutive adult SLE patients presenting to a single healthcare center were considered for participation. The ACR neuropsychological battery for SLE was administered to consenting patients at 0, 6 and 12 months. Scores were compared with age- and sex-matched controls. Primary outcome was CD, defined as a z-score ≤-1.5 in two or more cognitive domains. Mixed-effects logistic regression models were constructed to estimate the odds of CD with respect to AZA and MMF use. RESULTS: A total of 300 participants representing 676 patient visits completed the study; 114 (38%) met criteria for CD at baseline. The cumulative AZA dose (g/kg) was associated with reduced odds of CD [odds ratio (OR) 0.76 (95% CI 0.58, 0.98), P = 0.04]. Years of AZA treatment was also associated with reduced odds of CD [OR 0.72 (95% CI 0.54, 0.97), P = 0.03]. MMF use was not associated with CD. CONCLUSION: AZA use was associated with significantly lower odds of SLE-CD, while MMF use was not. Additional studies are warranted to further investigate the relationship of AZA and SLE-CD.


Asunto(s)
Azatioprina , Lupus Eritematoso Sistémico , Adulto , Humanos , Azatioprina/uso terapéutico , Ácido Micofenólico/uso terapéutico , Inmunosupresores/uso terapéutico , Inhibidores Enzimáticos , Cognición , Lupus Eritematoso Sistémico/tratamiento farmacológico
3.
Int J Mol Sci ; 20(6)2019 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-30917509

RESUMEN

An inverse association exists between physical activity and breast cancer incidence and outcomes. An objective indicator of an individual's recent physical activity exposure is aerobic capacity. We took advantage of the fact that there is an inherited as well as inducible component of aerobic capacity to show that experimentally induced mammary cancer is inversely related to inherent aerobic capacity (IAC). The objective of this study was to determine whether cell signaling pathways involved in the development of mammary cancer differed in rats with low inherent aerobic capacity (LIAC, n = 55) versus high inherent aerobic capacity (HIAC, n = 57). Cancer burden was 0.21 ± 0.16 g/rat in HIAC versus 1.14 ± 0.45 in LIAC, p < 0.001. Based on protein expression, cancer in LIAC animals was associated with upregulated glucose utilization, and protein and fatty acid synthesis. Signaling in cancers from HIAC rats was associated with energy sensing, fatty acid oxidation and cell cycle arrest. These findings support the thesis that pro-glycolytic, metabolic inflexibility in LIAC favors not only insulin resistance and obesity but also tumor development and growth. This provides an unappreciated framework for understanding how obesity and low aerobic fitness, hallmarks of physical inactivity, are associated with higher cancer risk and poorer prognosis.


Asunto(s)
Carcinoma/metabolismo , Neoplasias Mamarias Experimentales/metabolismo , Consumo de Oxígeno , Transducción de Señal , Animales , Carcinoma/etiología , Metabolismo Energético , Ácidos Grasos/biosíntesis , Femenino , Glucosa/metabolismo , Neoplasias Mamarias Experimentales/etiología , Biosíntesis de Proteínas , Ratas
4.
Carcinogenesis ; 38(9): 920-928, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28911004

RESUMEN

Although regular physical activity is associated with improvement in aerobic capacity and lower breast cancer risk, there are heritable sets of traits that affect improvement in aerobic capacity in response to physical activity. Although aerobic capacity segregates risk for a number of chronic diseases, the effect of the heritable component on cancer risk has not been evaluated. Therefore, we investigated breast carcinogenesis in rodent models of heritable fitness in the absence of induced physical activity. Female offspring of N:NIH rats selectively bred for low (LIAC) or high (HIAC) inherent aerobic capacity were injected intraperitoneally with 1-methyl-1-nitrosurea (70 mg/kg body wt). At study termination 33 weeks post-carcinogen, cancer incidence (14.0 versus 47.3%; P < 0.001) and multiplicity (0.18 versus 0.85 cancers per rat; P < 0.0001) were significantly decreased in HIAC versus LIAC rats, respectively. HIAC had smaller visceral and subcutaneous body fat depots than LIAC and activity of two proteins that regulated the mammalian target of rapamycin, protein kinase B (Akt), and adenosine monophosphate-activated protein kinase were suppressed and activated, respectively, in HIAC. Although many factors distinguish between HIAC and LIAC, it appears that the protective effect of HIAC against breast carcinogenesis is mediated, at least in part, via alterations in core metabolic signaling pathways deregulated in the majority of human breast cancers.


Asunto(s)
Carcinogénesis/genética , Neoplasias Mamarias Experimentales/genética , Condicionamiento Físico Animal , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Biomarcadores de Tumor/sangre , Carcinogénesis/inducido químicamente , Femenino , Neoplasias Mamarias Experimentales/inducido químicamente , Neoplasias Mamarias Experimentales/metabolismo , Metilnitrosourea/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Factores de Riesgo , Serina-Treonina Quinasas TOR/metabolismo
5.
Bioorg Med Chem Lett ; 26(2): 630-635, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26639761

RESUMEN

We report the synthesis, antibacterial evaluation of a series of thiourea-containing compounds. 1-(3,5-Bis(trifluoromethyl)phenyl)-3-((S)-(6-methoxyquinolin-4-yl)-((1S,2S,4S,5R)-5-vinylquinuclidin-2-yl)methyl)thiourea 5, was the most active against a range of Gram-positive and Gram-negative bacteria, and exhibited bacteriostatic activity against methicillin resistant Staphylococcus aureus (MRSA) comparable to that of the well-known antibacterial agent vancomycin. Quinoline thiourea 5 was subjected to a detailed structure-activity relationship study, with 5 and its derivatives evaluated for their bacteriostatic activity against both Gram-negative and Gram-positive bacteria. A number of structural features important for the overall activity of quinoline thiourea 5 have been identified. A selection of compounds, including 5, was also evaluated for their in vivo toxicity using the larvae of the Greater wax moth, Galleria mellonella. Compound 5, and a number of derivatives, were found to be non-toxic to the larvae of Galleria mellonella. A new class of antibiotic can result from the further development of this family of compounds.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Quinolinas/química , Quinolinas/farmacología , Tiourea/análogos & derivados , Tiourea/farmacología , Antibacterianos/síntesis química , Infecciones Bacterianas/tratamiento farmacológico , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Quinolinas/síntesis química , Relación Estructura-Actividad , Tiourea/síntesis química , Vancomicina/farmacología
6.
Chemosphere ; 349: 140823, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38042422

RESUMEN

Once released into the environment, herbicides can move through soil or surface water to streams and groundwater. Filters containing adsorbent media placed in fields may be an effective solution to herbicide loss in the environment. However, to date, no study has investigated the use of adsorbent materials in intervention systems at field-scale, nor has any study investigated their optimal configuration. Therefore, the aim of this paper was to examine the efficacy of low-cost, coconut-based activated carbon (CAC) intervention systems, placed in streams and tributaries, for herbicide removal. Two configurations of interventions were investigated in two agricultural catchments and one urban area in Ireland: (1) filter bags and (2) filter bags fitted into polyethylene pipes. Herbicide sampling was conducted using Chemcatcher® passive sampling devices in order to identify trends in herbicide exceedances at the sites, and to quantifiably assess, compare, and contrast the efficiency of the two intervention configurations. While the Chemcatcher® passive sampling devices are capable of analysing eighteen different acid herbicides, only six different acid herbicides (2,4-D, clopyralid, fluroxypyr, MCPA, mecoprop and triclopyr) were ever detected within the three catchment areas, which were also the only acid herbicides used therein. The CAC was capable of complete herbicide removal, when the water flow was slow (0.5-1 m3 s-1), and the interventions spanned the width and depth of the waterway. Overall, the reduction in herbicide concentrations was better for the filter pipes than for the filter bags, with a 48% reduction in detections and a 37% reduction in exceedances across all the sampling sites for the filter pipe interventions compared to a 13% reduction in the number of detections and a 24% reduction in exceedances across all sampling sites for the filter bag interventions (p < 0.05). This study demonstrates, for the first time, that CAC may be an effective in situ remediation strategy to manage herbicide exceedances close to the source, thereby reducing the impact on environmental and public health.


Asunto(s)
Herbicidas , Contaminantes Químicos del Agua , Herbicidas/análisis , Cocos , Carbón Orgánico , Agricultura , Agua , Contaminantes Químicos del Agua/análisis
7.
Nutrients ; 15(3)2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36771233

RESUMEN

Hepatic steatosis signifies onset of metabolic dysfunction-associated fatty liver disease (MAFLD) caused by disrupted metabolic homeostasis compromising liver function. Regular consumption of common beans reduces the risk of metabolic impairment, but its effective dose, the impact of biological sex, and underlying mechanisms of action are unknown. We fed female and male C57BL6/J mice with obesogenic yet isocaloric diets containing 0%, 17.5%, 35%, and 70% of total dietary protein derived from cooked whole common beans. Liver tissue was collected for histopathology, lipid quantification, and RNA-seq analyses. Beans qualitatively and quantitatively diminished hepatic fat deposition at the 35% dose in female and 70% dose in male mice. Bean-induced differentially expressed genes (DEGs) most significantly mapped to hepatic steatosis and revealed dose-responsive inhibition of de novo lipogenesis markers (Acly, Acaca, Fasn, Elovl6, Scd1, etc.) and triacylglycerol biosynthesis, activation of triacylglycerol degradation, and downregulation of sterol regulatory element-binding transcription factor 1 (SREBF1) signaling. Upregulated fatty acid ß-oxidation was more prominent in females, while suppression of Cd36-mediated fatty acid uptake-in males. Sex-dependent bean effects also involved DEGs patterns downstream of peroxisome proliferator-activated receptor α (PPARα) and MLX-interacting protein-like (MLXIPL). Therefore, biological sex determines amount of common bean in the diet required to prevent hepatic lipid accumulation.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Phaseolus , Masculino , Femenino , Ratones , Animales , Phaseolus/metabolismo , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/prevención & control , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Hígado/metabolismo , Ácidos Grasos/metabolismo , Lipogénesis , Triglicéridos/metabolismo
8.
Nutrients ; 15(9)2023 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-37432145

RESUMEN

Obesity prevention is stated as a simple objective in the public health guidelines of most countries: avoid adult weight gain. However, the success of the global population in accomplishing this goal is limited as reflected in the persisting pandemic of overweight and obesity. While many intervention strategies have been proposed, most are directed at mitigating the consequences of obesity. Efforts intended to prevent unintentional weight gain and associated adiposity are termed anti-obesogenic. Herein, evidence is presented that a neglected category of foods, pulses, i.e., grain legumes, have anti-obesogenic activity. Using a preclinical mouse model of obesity, a dose-response study design in animals of both biological sexes, and cooked, freeze-dried, and milled common bean as a representative pulse, data are presented showing that the rate of body weight gain is slowed, and fat accumulation is suppressed when 70% of the dietary protein is provided from common bean. These anti-obesogenic effects are reduced at lower amounts of common bean (17.5% or 35%). The anti-obesogenic responsiveness is greater in female than in male mice. RNA sequence analysis indicates that the sex-related differences extend to gene expression patterns, particularly those related to immune regulation within adipose tissue. In addition, our findings indicate the potential value of a precision nutrition approach for human intervention studies that identify "pulse anti-obesogenic responders". A precision approach may reduce the concentration of pulses required in the diet for benefits, but candidate biomarkers of responsivity to pulse consumption remain to be determined.


Asunto(s)
Adiposidad , Phaseolus , Adulto , Humanos , Femenino , Masculino , Animales , Ratones , Obesidad/prevención & control , Aumento de Peso , Verduras
9.
Nutrients ; 15(9)2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37432381

RESUMEN

While diet and nutrition are modifiable risk factors for many chronic and infectious diseases, their role in cancer prevention and control remains under investigation. The lack of clarity of some diet-cancer relationships reflects the ongoing debate about the relative contribution of genetic factors, environmental exposures, and replicative errors in stem cell division as determinate drivers of cancer risk. In addition, dietary guidance has often been based upon research assuming that the effects of diet and nutrition on carcinogenesis would be uniform across populations and for various tumor types arising in a specific organ, i.e., that one size fits all. Herein, we present a paradigm for investigating precision dietary patterns that leverages the approaches that led to successful small-molecule inhibitors in cancer treatment, namely understanding the pharmacokinetics and pharmacodynamics of small molecules for targeting carcinogenic mechanisms. We challenge the scientific community to refine the paradigm presented and to conduct proof-in-concept experiments that integrate existing knowledge (drug development, natural products, and the food metabolome) with developments in artificial intelligence to design and then test dietary patterns predicted to elicit drug-like effects on target tissues for cancer prevention and control. We refer to this precision approach as dietary oncopharmacognosy and envision it as the crosswalk between the currently defined fields of precision oncology and precision nutrition with the goal of reducing cancer deaths.


Asunto(s)
Neoplasias , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/prevención & control , Inteligencia Artificial , Medicina de Precisión , Dieta , Estado Nutricional
10.
Carcinogenesis ; 33(1): 226-32, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22072617

RESUMEN

Emerging evidence indicates that common bean (Phaseolus vulgaris L.) is associated with reduced cancer risk in human populations and rodent carcinogenesis models. This study sought to identify cancer-associated molecular targets that mediate the effects of bean on cancer burden in a chemically induced rat model for breast cancer. Initial experiments were conducted using a high dietary concentration of bean (60% wt/wt) where carcinoma burden in bean-fed rats was reduced 62.2% (P < 0.001) and histological and western blot analyses revealed that the dominant cellular process associated with reduced burden was induction of apoptosis. Further analysis of mammary carcinomas revealed changes in the phosphorylation states of mammalian target of rapamycin (mTOR) substrates (4E-binding protein 1 and p70S6 kinase) and mTOR regulators adenosine monophosphate-activated protein kinase and protein kinase B (Akt) (P < 0.001). Effects on mTOR signaling in carcinomas were also found at lower dietary concentrations of bean (7.5-30% wt/wt). Liquid chromatography-time of flight-mass spectrometry analysis of plasma provided evidence of altered lipid metabolism consistent with reduced mTOR network activity in the liver (P < 0.001). Plasma concentrations of insulin and insulin-like growth factor-1 were reduced by 36.3 and 38.9%, respectively, (P < 0.001), identifying a link to Akt regulation. Plasma C-reactive protein, a prognostic marker for long-term survival in breast cancer patients, was reduced by 23% (P < 0.001) in bean-fed rats. Identification of a role for the mTOR signaling network in the reduction of cancer burden by dietary bean is highly relevant given that this pathway is deregulated in the majority of human breast cancers.


Asunto(s)
Neoplasias Mamarias Experimentales/prevención & control , Phaseolus , Transducción de Señal/fisiología , Animales , Apoptosis , Proliferación Celular , Dieta , Femenino , Antígeno Ki-67/análisis , Neoplasias Mamarias Experimentales/patología , Metaboloma , Ratas , Ratas Sprague-Dawley , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Serina-Treonina Quinasas TOR/fisiología
11.
Breast Cancer Res ; 14(1): R1, 2012 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-22225711

RESUMEN

INTRODUCTION: Healthy body weight is an important factor for prevention of breast cancer recurrence. Yet, weight loss and weight gain are not currently included in clinical-practice guidelines for posttreatment of breast cancer. The work reported addresses one of the questions that must be considered in recommending weight loss to patients: does it matter what diet plan is used, a question of particular importance because breast cancer treatment can increase risk for cardiovascular disease. METHODS: Women who completed treatment for breast cancer were enrolled in a nonrandomized, controlled study investigating effects of weight loss achieved by using two dietary patterns at the extremes of macronutrient composition, although both diet arms were equivalent in protein: high fat, low carbohydrate versus low fat, high carbohydrate. A nonintervention group served as the control arm; women were assigned to intervention arms based on dietary preferences. During the 6-month weight-loss program, which was menu and recipe defined, participants had monthly clinical visits at which anthropometric data were collected and fasting blood was obtained for safety monitoring for plasma lipid profiles and fasting glucose. Results from 142 participants are reported. RESULTS: Adverse effects on fasting blood lipids or glucose were not observed in either dietary arm. A decrease in fasting glucose was observed with progressive weight loss and was greater in participants who lost more weight, but the effect was not statistically significant, even though it was observed across both diet groups (P = 0.21). Beneficial effects of weight loss on cholesterol (4.7%; P = 0.001), triglycerides (21.8%; P = 0.01), and low-density lipoprotein (LDL) cholesterol (5.8%; P = 0.06) were observed in both groups. For cholesterol (P = 0.07) and LDL cholesterol (P = 0.13), greater reduction trends were seen on the low-fat diet pattern; whereas, for triglycerides (P = 0.01) and high-density lipoprotein (HDL) cholesterol (P = 0.08), a decrease or increase, respectively, was greater on the low-carbohydrate diet pattern. CONCLUSIONS: Because an individual's dietary preferences can affect dietary adherence and weight-loss success, the lack of evidence of a negative effect of dietary pattern on biomarkers associated with cardiovascular risk is an important consideration in the development of breast cancer practice guidelines for physicians who recommend that their patients lose weight. Whether dietary pattern affects biomarkers that predict long-term survival is a primary question in this ongoing clinical trial.


Asunto(s)
Glucemia , Neoplasias de la Mama/prevención & control , Lípidos/sangre , Recurrencia Local de Neoplasia/prevención & control , Obesidad/dietoterapia , Sobrevivientes , Índice de Masa Corporal , Dieta Reductora , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Femenino , Humanos , Persona de Mediana Edad , Análisis de Regresión , Resultado del Tratamiento , Pérdida de Peso
12.
Br J Nutr ; 108 Suppl 1: S155-65, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22916811

RESUMEN

Metabolite profiling using liquid chromatography-time-of-flight MS was undertaken to identify candidate metabolic processes that account for dry bean effects on disease risk with a specific focus on the development of breast cancer. Normal mammary gland and mammary carcinomas from previously reported experiments were evaluated. Principal component analysis (PCA) of mass spectral data revealed that tissue of both types from control-fed v. bean-fed rats could be distinguished by their metabolomic profiles. Candidate ion identification using MassTRIX analysis software revealed that alterations in eicosanoid, fatty acid, TAG and steroid metabolism partially accounted for the differences observed in both PCA. In addition, evidence was obtained consistent with the hypothesis that the varying inhibitory effects on mammary carcinogenesis of genetically distinct dry bean types were mirrored by differential patterns of lipid metabolites in mammary carcinoma. The use of MassTRIX provided links for metabolite profile enrichment with metabolic pathways in the Kyoto Encyclopedia of Genes and Genomes. Implicated pathways included a linkage between diacylglycerol and protein kinase C and eicosanoid metabolites and inducible cyclo-oxygenase-2 and/or eicosanoid degradation mediated via 15-PG dehydrogenase. These pathways have been reported to be misregulated during the development of cancer. The differences observed between control-fed and bean-fed rats in lipid metabolism require validation using targeted analytical methods and detailed analyses of how bean bioactive food components regulate genes that control lipid biosynthesis, interconversion and catabolism.


Asunto(s)
Dieta , Metabolismo de los Lípidos , Neoplasias Mamarias Experimentales/metabolismo , Metabolómica , Phaseolus , Semillas , Animales , Diglicéridos/análisis , Ácidos Grasos/análisis , Ácidos Grasos/metabolismo , Ácidos Grasos Omega-6/análisis , Femenino , Alimentos en Conserva , Glándulas Mamarias Animales/química , Glándulas Mamarias Animales/metabolismo , Neoplasias Mamarias Experimentales/química , Neoplasias Mamarias Experimentales/patología , Phaseolus/genética , Prostaglandinas/análisis , Ratas , Ratas Sprague-Dawley , Semillas/genética , Especificidad de la Especie , Triglicéridos/biosíntesis
13.
Biomedicines ; 11(1)2022 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-36672557

RESUMEN

Damage to cellular macromolecules such as DNA and lipid, induced via reactive oxygen species, and indicators of cell proliferation potential such as insulin-like growth factor (IGF) metabolic status are intermediate biomarkers of breast cancer risk. Based on reports that selenium status can affect these markers, a randomized, placebo-controlled, double-blind experiment was conducted to investigate the potential of selenium supplementation to modulate breast cancer risk. Using a placebo tablet or a tablet containing 200 µg selenium provided as high-selenium yeast daily for one year, concentrations of the biomarkers in blood or urine were assessed at baseline and after 6 and 12 months of intervention. The selenium intervention used in this study is presumed to mediate its effect via the induction of glutathione peroxidase activity and the consequential impact of the active form of this protein on oxidative damage. We found no evidence to support this hypothesis or to indicate that systemic IGF metabolic status was affected. Critical knowledge gaps must be addressed for the resurgence of interest in selenium and cancer to garner clinical relevance. Those knowledge gaps include the identification of a specific, high-affinity selenium metabolite and the cellular target(s) to which it binds, and the demonstration that the cellular determinant that the selenium metabolite binds plays a critical role in the initiation, promotion, or progression of a specific type of cancer.

14.
Foods ; 11(8)2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35454741

RESUMEN

Underconsumption of dietary fiber and the milieu of chemicals with which it is associated is a health concern linked to the increasing global burden of chronic diseases. The benefits of fiber are partially attributed to modulation of the gut microbiota, whose composition and function depend on the amount and quality of microbiota-accessible substrates in the diet. However, not all types of fiber are equally accessible to the gut microbiota. Phaseolus vulgaris L., or common bean, is a food type rich in fiber as well as other prebiotics posing a great potential to positively impact diet-microbiota-host interactions. To elucidate the magnitude of bean's effects on the gut microbiota, increasing doses of common bean were administered in macronutrient-matched diet formulations. The microbial communities in the ceca of female and male mice were evaluated via 16S rRNA gene sequencing. As the bean dose increased, the Bacillota:Bacteroidota ratio (formerly referred to as the Firmicutes:Bacteroidetes ratio) was reduced and α-diversity decreased, whereas the community composition was distinctly different between the diet groups according to ß-diversity. These effects were more pronounced in female mice compared to male mice. Compositional analyses identified a dose-responsive bean-induced shift in microbial composition. With an increasing bean dose, Rikenellaceae, Bacteroides, and RF39, which are associated with health benefits, were enhanced. More taxa, however, were suppressed, among which were Allobaculum, Oscillospira, Dorea, and Ruminococcus, which are predominantly associated with chronic disease risk. Investigation of the origins of the dose dependent and biological sex differences in response to common bean consumption may provide insights into bean-gut microbiota-host interactions important to developing food-based precision approaches to chronic disease prevention and control.

15.
Soil Use Manag ; 38(2): 1162-1171, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35915848

RESUMEN

Pesticides are widely employed as a cost-effective means of reducing the impacts of undesirable plants and animals. The aim of this paper is to develop a risk ranking of transmission of key pesticides through soil to waterways, taking into account physico-chemical properties of the pesticides (soil half-life and water solubility), soil permeability, and the relationship between adsorption of pesticides and soil texture. This may be used as a screening tool for land managers, as it allows assessment of the potential transmission risks associated with the use of specified pesticides across a spectrum of soil textures. The twenty-eight pesticides examined were differentiated into three groups: herbicides, fungicides and insecticides. The highest risk of pesticide transmission through soils to waterways is associated with soils containing <20% clay or >45% sand. In a small number of cases, the resulting transmission risk is not influenced by soil texture alone. For example, for Phenmedipham, the transmission risk is higher for clay soils than for silt loam. The data generated in this paper may also be used in the identification of critical area sources, which have a high likelihood of pesticide transmission to waterways. Furthermore, they have the potential to be applied to GIS mapping, where the potential transmission risk values of the pesticides can be layered directly onto various soil textures.

16.
Biol Proced Online ; 13(1): 4, 2011 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-21663682

RESUMEN

BACKGROUND: Rodent models have been used extensively to study mammary gland development and for studies of toxicology and carcinogenesis. Mammary gland gross morphology can visualized via the excision of intact mammary gland chains following fixation and staining with carmine using a tissue preparation referred to as a whole mount. Methods are described for the automated collection of digital images from an entire mammary gland whole mount and for the interrogation of digital data using a "masking" technique available with Image-Pro® plus image analysis software (Mediacybernetics. Silver Spring, MD). RESULTS: Parallel to mammographic analysis in humans, measurements of rodent mammary gland density were derived from area-based or volume-based algorithms and included: total circumscribed mammary fat pad mass, mammary epithelial mass, and epithelium-free fat pad mass. These values permitted estimation of absolute mass of mammary epithelium as well as breast density. The biological plausibility of these measurements was evaluated in mammary whole mounts from rats and mice. During mammary gland development, absolute epithelial mass increased linearly without significant changes in mammographic density. Treatment of rodents with tamoxifen, 9-cis-retinoic acid, or ovariectomy, and occurrence of diet induced obesity decreased both absolute epithelial mass and mammographic density. The area and volumetric methods gave similar results. CONCLUSIONS: Digital image analysis can be used for screening agents for potential impact on reproductive toxicity or carcinogenesis as well as for mechanistic studies, particularly for cumulative effects on mammary epithelial mass as well as translational studies of mechanisms that explain the relationship between epithelial mass and cancer risk.

17.
BMC Cancer ; 11: 287, 2011 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-21733177

RESUMEN

BACKGROUND: Weight loss in overweight or obese breast cancer patients is associated with an improved prognosis for long term survival. However, it is not clear whether the macronutrient composition of the chosen weight loss dietary plan imparts further prognostic benefit. A study protocol is presented for a dietary intervention to investigate the effects of weight loss dietary patterns that vary markedly in fat and carbohydrate contents on biomarkers of exposure to metabolic processes that may promote tumorigenesis and that are predictive of long term survival. The study will also determine how much weight must be lost for biomarkers to change in a favorable direction. METHODS/DESIGN: Approximately 370 overweight or obese postmenopausal breast cancer survivors (body mass index: 25.0 to 34.9 kg/m²) will be accrued and assigned to one of two weight loss intervention programs or a non-intervention control group. The dietary intervention is implemented in a free living population to test the two extremes of popular weight loss dietary patterns: a high carbohydrate, low fat diet versus a low carbohydrate, high fat diet. The effects of these dietary patterns on biomarkers for glucose homeostasis, chronic inflammation, cellular oxidation, and steroid sex hormone metabolism will be measured. Participants will attend 3 screening and dietary education visits, and 7 monthly one-on-one dietary counseling and clinical data measurement visits in addition to 5 group visits in the intervention arms. Participants in the control arm will attend two clinical data measurement visits at baseline and 6 months. The primary outcome is high sensitivity C-reactive protein. Secondary outcomes include interleukin-6, tumor necrosis factor-α, insulin-like growth factor-1 (IGF), IGF binding protein-3, 8-isoprostane-F2-alpha, estrone, estradiol, progesterone, sex hormone binding globulin, adiponectin, and leptin. DISCUSSION: While clinical data indicate that excess weight for height is associated with poor prognosis for long term survival, little attention is paid to weight control in the clinical management of breast cancer. This study will provide information that can be used to answer important patient questions about the effects of dietary pattern and magnitude of weight loss on long term survival following breast cancer treatment. CLINICAL TRIAL REGISTRATION: CA125243.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/dietoterapia , Dieta Reductora , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Sobrevivientes , Adiponectina/sangre , Tejido Adiposo/metabolismo , Algoritmos , Análisis de Varianza , Neoplasias de la Mama/metabolismo , Proteína C-Reactiva/metabolismo , Estrógenos/sangre , Femenino , Glucosa/metabolismo , Homeostasis/efectos de los fármacos , Humanos , Interleucina-6/metabolismo , Leptina/sangre , Persona de Mediana Edad , Obesidad/sangre , Evaluación de Resultado en la Atención de Salud/métodos , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Posmenopausia/sangre , Especies Reactivas de Oxígeno/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Programas de Reducción de Peso/métodos , Programas de Reducción de Peso/estadística & datos numéricos
18.
J Carcinog ; 10: 17, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21799661

RESUMEN

BACKGROUND: This study examined whether metformin administration inhibited chemically induced mammary carcinogenesis in rats. In cancer prevention, metformin may act (1) indirectly through reducing systemic risk factors; or (2) directly through AMPK-mediated signaling. To begin to delineate clinically relevant mechanisms for breast cancer prevention, metformin was also studied along with dietary energy restriction. MATERIALS AND METHODS: Mammary cancer was induced in female Sprague--Dawley rats (50 mg/kg MNU, i.p.). Metformin was fed alone (AIN93G + 0.05 to 1.0% w/w metformin) or combined with 40% dietary energy restriction. Plasma analytes (e.g., insulin, glucose, IGF-1) and protein expression (e.g., AMPK, mTOR, Akt) in mammary carcinomas and liver were evaluated. Additional studies included (1) aldehyde dehydrogenase flow cytometry, to gauge potential for cancer-initiated cells in mammary carcinomas to respond to metformin; (2) cell culture, to understand dose response (0.02--20 mM) of different cancer cell line molecular subtypes to metformin; and (3) analysis of a rat mammary epithelial cell microarray database, to examine expression of genes related to metformin pharmacokinetics (e.g., organic cation transporters) and pharmacodynamics (e.g., complex I of electron transport). RESULTS: While a dosing regimen of 1.0%/0.25% metformin-reduced palpable mammary carcinoma incidence, multiplicity, and tumor burden and prolonged latency, lower doses of metformin failed to inhibit carcinogenesis despite effects on plasma insulin. Human breast cancer cell growth inhibition in response to metformin was only observed at high concentrations. Poor in vivo and in vitro response to metformin may be the result of pharmacokinetic (OCT-1 expression was low in rat mammary cells; OCT-3 was downregulated in mammary carcinoma) and pharmacodynamic (complex I transcripts were higher in mammary epithelial cells from carcinomas versus uninvolved gland) effects. In combination with dietary energy restriction, metformin offered protection against new tumor occurrence following release from combined treatment. Flow cytometry indicated the presence of cancer-initiated cells in mammary carcinomas. CONCLUSIONS: As a single agent, metformin possessed limited cancer inhibitory activity. However, metformin may be an effective component of multiagent interventions that target cancer-initiated cells. There is a clear need to identify the conditions under which metformin is likely to benefit prevention and control of breast cancer.

19.
Biomedicines ; 9(11)2021 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-34829880

RESUMEN

Population studies, systematic reviews, and meta-analyses have revealed no relationship between iron status and breast cancer, a weak positive association, or a small protective effect of low iron status. However, in those studies, the authors concluded that further investigation was merited. The set of experiments reported here used preclinical models to assess the likely value of further investigation. The effects of iron status on the initiation and promotion stage of mammary carcinogenesis are reported. Using the classical model of cancer initiation in the mammary gland, 7,12 dimethyl-benz[α]anthracene-induced carcinogenesis was unaffected by iron status. Similarly, excess iron intake showed no effect on the promotion stage of 1-methyl-1-nitrosurea-induced mammary carcinogenesis, though iron deficiency exerted a specific inhibitory effect on the carcinogenic process. Though iron-mediated cellular oxidation is frequently cited as a potential mechanism for effects on breast cancer, no evidence of increased oxidative damage to DNA attributable to excess iron intake was found. The reported preclinical data fail to provide convincing evidence that the further evaluation of the iron-breast cancer risk hypotheses is warranted and underscore the value of redefining the referent group in population-based studies of iron-cancer hypotheses in other tissues.

20.
Seizure ; 91: 402-408, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34303161

RESUMEN

BACKGROUND: This study evaluated the association between eligible patients not proceeding with resective epilepsy surgery and various demographic, disease-specific, and epilepsy-evaluation variables. METHODS: This retrospective case-control study included patients identified as candidates for resective epilepsy surgery at the Montefiore Medical Center between January 1, 2009 and June 30, 2017. Chi-squared, two-tailed, independent sample t-test, Mann-Whitney U test and logistic regression were utilized to identify variables associated with patients not proceeding with surgery. RESULTS: Among the 159 potential surgical candidates reviewed over the 8.5-year study period, only 53 ultimately proceeded with surgery (33%). Eighty-seven (55%) out of these 159 patients were identified as appropriate for resective epilepsy surgery during the study period. Thirty-four (39%) of these 87 patients did not proceed with surgery. Variables independently correlated (either positively or negatively) with the patient not proceeding with surgery were: being employed [Odds Ratio (OR) 4.2, 95% confidence interval (CI) 1.12-15.73], temporal lobe lesion on MRI (OR 0.35, 95% CI 0.14-0.84), temporal lobe EEG ictal onsets (OR 0.21, 95% CI 0.07-0.62), and temporal lobe epileptogenic zone (OR 0.19, 95% CI 0.07-0.55). CONCLUSION: The novel finding in this study is the association between employment status and whether the patient had epilepsy surgery: employed patients were 4.2 times more likely to not proceed with surgery compared to unemployed patients. In addition, patients with a temporal lobe lesion on MRI, temporal lobe EEG ictal onsets, and/or a temporal epileptogenic zone were more likely to proceed with surgery. Future work will be needed to evaluate these findings prospectively, determine if they generalize to other patient populations, explore the decision whether or not to proceed with epilepsy surgery from a patient-centered perspective, and suggest strategies to reduce barriers to this underutilized treatment.


Asunto(s)
Epilepsia del Lóbulo Temporal , Epilepsia , Estudios de Casos y Controles , Electroencefalografía , Epilepsia/diagnóstico por imagen , Epilepsia/cirugía , Humanos , Imagen por Resonancia Magnética , Estudios Retrospectivos , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/cirugía , Resultado del Tratamiento
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