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1.
Chronic inflammation is one of the most common and well-recognized risk factors for human cancer, including colon cancer. Inflammatory bowel disease (IBD) is defined as a longstanding idiopathic chronic active inflammatory process in the colon, including ulcerative colitis and Crohn’s disease. Importantly, patients with IBD have a significantly increased risk for the development of colorectal carcinoma. Dietary inositol and its phosphates, as well as phospholipid derivatives, are well known to benefit human health in diverse pathologies including cancer prevention. Inositol phosphates including InsP3, InsP6, and other pyrophosphates, play important roles in cellular metabolic and signal transduction pathways involved in the control of cell proliferation, differentiation, RNA export, DNA repair, energy transduction, ATP regeneration, and numerous others. In the review, we highlight the biologic function and health effects of inositol and its phosphates including the nature and sources of these molecules, potential nutritional deficiencies, their biologic metabolism and function, and finally, their role in the prevention of colitis-induced carcinogenesis.  相似文献   

2.
Combination therapy is based on the beneficial effects of pharmacodynamic interaction (synergistic or additive) between combined drugs or substances. A considerable group of candidates for combined treatments are natural compounds (e.g., isothiocyanates) and their analogs, which are tested in combination with anticancer drugs. We tested the anticancer effect of the combined treatment of isothiocyanate 2-oxohexyl isothiocyanate and 5-fluorouracil in colon and prostate cancer cell lines. The type of interaction was described using the Chou-Talalay method. The cytostatic and cytotoxic activities of the most promising combined treatments were investigated. In conclusion, we showed that combined treatment with 5-fluorouracil and 2-oxohexyl isothiocyanate acted synergistically in colon cancer. This activity is dependent on the cytostatic properties of the tested compounds and leads to the intensification of their individual cytotoxic activity. The apoptotic process is considered to be the main mechanism of cytotoxicity in this combined treatment.  相似文献   

3.
Nucleotide excision repair (NER) is the primary defense against the DNA damage implicit in skin cancer formation and is negatively affected by chronic exposure to UVB radiation. However, in situ and in vitro studies consistently yield equivocal results when addressing individual DNA repair capacity and melanoma susceptibility. The primary objective of this study was to determine if individual global NER capacity is a risk factor for melanoma formation in a prominent UVB‐inducible melanoma model, hybrid Xiphophorus fishes. After neonatal UVB irradiation, adult tumor‐bearing and tumor‐free fish were given a challenge UVB dose and (6–4) photoproduct repair was quantified in individual fish at 24 h using radioimmunoassay. Despite considerable inter‐individual variation in repair capacity, ranging from 13% to 91%, we found no difference in mean NER capacity between fish with and without melanomas, thus detaching global NER from melanomagenesis. Furthermore, despite epidemiological data indicating that sex and age are important risk factors underlying melanoma susceptibility, we found no difference in mean NER rates among the sexes or as a function of age. We conclude with a discussion of the apparent paradox of how inter‐individual variation in NER is not a risk factor given the clear evidence that DNA damage underlies melanoma susceptibility.  相似文献   

4.
Resistant starches and health   总被引:3,自引:0,他引:3  
It was initially hypothesized that resistant starches, i.e., starch that enters the colon, would have protective effects on chronic colonic diseases, including reduction of colon cancer risk and in the treatment of ulcerative colitis. Recent studies have confirmed the ability of resistant starch to increase fecal bulk, increase the molar ratio of butyrate in relation to other short-chain fatty acids, and dilute fecal bile acids. However the ability of resistant starch to reduce luminal concentrations of compounds that are damaging to the colonic mucosa, including fecal ammonia, phenols, and N-nitroso compounds, still requires clear demonstration. As such, the effectiveness of resistant starch in preventing or treating colonic diseases remains to be assessed. Nevertheless, there is a fraction of what has been termed resistant (RS1) starch, which enters the colon and acts as slowly digested or lente carbohydrate in the small intestine. Foods in this class are low glycemic index and have been shown to reduce the risk of chronic disease. They have been associated with systemic physiological effects such as reduced postprandial insulin levels and higher HDL cholesterol levels. Consumption of low glycemic index foods has been shown to be related to reductions in risk of coronary heart disease and Type 2 diabetes. Type 2 diabetes has in turn been related to a higher risk of colon cancer. If carbohydrates have a protective role in colon cancer prevention this may lie partly in the systemic effects of low glycemic index foods. The colonic advantages of different carbohydrates, varying in their glycemic index and resistant starch content, therefore, remain to be determined. However, as recent positive research findings continue to mount, there is reason for optimism over the possible health advantages of those resistant starches, which are slowly digested in the small intestine.  相似文献   

5.
Cancer stem cells (CSCs) are known to be resistant to conventional chemotherapy and radiotherapy. Specific CSC targeting and eradication is therefore a therapeutically important challenge. CD133 is a colorectal CSC marker with unknown function(s). Assessing proteomic changes induced by CD133 may provide clues not only to new CD133 functions but also to the chemotherapy and radiation susceptibility of colon cancer cells. To identify the proteins affected by CD133, CD133‐positive (CD133+), and CD133‐negative (CD133–) human colon cancer cells were obtained by cell sorting. Whole proteomes were profiled from SW620/CD133+ and SW620/CD133– cells and analyzed by 2D‐based proteome analysis. Nucleophosmin (NPM1) was identified as a protein regulated by CD133. CD133 protein level was not affected by NPM1, and an interaction between the two proteins was not observed. CD133 and NPM1 protein levels were positively correlated in 11 human colon cancer cell lines. The CD133+ subpopulation percentage or its value normalized against CD133 protein level was only linked to intrinsic susceptibility of human colon cancer cells to 5‐fluorouracil (5‐FU). However, either suppression of CD133 or NPM1 significantly increased 5‐FU susceptibility of SW620. The present study suggests that CD133‐regulated NPM1 protein level may provide a clue to novel CD133 function(s) linked to human colon cancer cell susceptibility to chemotherapy.  相似文献   

6.
Most common diseases appear to result from complex, poorly understood interactions between genetic and environmental factors. Relatively few factors have been unequivocally linked with disease risk or outcome. Evidence from various studies using different experimental approaches has been interpreted as showing that, apart from its harmful effects on the pathogenesis of the common skin cancers, ultraviolet radiation (UVR) may exert a beneficial effect on development of various internal cancers and other pathologies. This concept is supported by parallel studies showing that hypovitaminosis D is linked with increased risk of various diseases including insulin resistance and multiple sclerosis. These findings suggest that, first, host factors such as skin pigmentation that affect UVR-induced synthesis of vitamin D and, second, polymorphism in genes that mediate the effectiveness of vitamin D action are susceptibility candidates for a variety of diseases. Collectively, these data suggest the hypothesis that, via effects on vitamin D synthesis, UVR exposure has beneficial effects on susceptibility and outcome to a variety of complex diseases. We describe evidence from studies in various diseases, but mainly from prostate cancer patients, that supports this hypothesis, but we emphasize that, although supportive data are available, the concept is unproven. Indeed, other explanations are possible. However, given the potentially important public health implications of the hypothesis and the potential for the development of novel therapeutic modalities, we believe the concept is worthy of further investigation.  相似文献   

7.
Although most health scientists now agree that health risks to the skin (e.g., skin cancer) exist from exposure to the ultraviolet radiation in sunlight, a scientific consensus has not really been achieved vis-à-vis sunlight and ocular health. A growing number of scientists warn of hazards to the eye if ultraviolet radiation - and perhaps even shorter wavelength visible radiation also - is not filtered by lenses. Despite a substantial literature on the adverse effects of ultraviolet radiation (UVR) and intense light upon ocular structures, particularly upon the retina, controversy still surrounds the question of whether the levels of natural and man-made light sources are damaging when encountered under normal viewing conditions. Although scientific evidence accumulates to indicate that chronic exposure conditions may accelerate ageing processes in ocular tissues, the quantitative question of "How much is safe?" remains to be answered conclusively.  相似文献   

8.
Hydrocolloids in the form of polymeric ingredients as well as natural biopolymer assemblies provide much of the macroscopic structure of foods. The controlled disassembly of hydrocolloid-structured foods in the digestive tract determines numerous nutritional properties driven by the rates of passage, digestion, absorption, and fermentation. Despite convincing evidence for health benefits of hydrocolloids (particularly dietary fibre) from epidemiology, and numerous in vitro model system studies, the detailed underlying mechanisms operating in the digestive tract are currently understood to only a limited extent. Distinct hydrocolloid-based processes occur in each of the gastric, small intestinal and large intestinal environments, with significant biological cross-talk between the sites. Hydrocolloids offer a major opportunity to tailor nutritional value and provide potential health benefits through control of gastric emptying and ileal brake mechanisms (satiety and potentially obesity), glycemic response (diabetes), plasma cholesterol levels (cardiovascular disease), and carbohydrate fermentation throughout the large intestine (colon cancer). There is often a parallel between the functionality of the plant-based foods which the human digestive tract evolved to digest and the use of extracted hydrocolloids in modern food structuring technology.  相似文献   

9.
Natural products have always enjoyed great popularity among consumers. Wild tea is an interesting alternative to tea from intensive plantations. The term “wild tea” is applied to many different varieties of tea, the most desirable and valued of which are native or indigenous tea plants. Special pro-health properties of wild tea are attributed to the natural conditions in which it grows. However, there are no complex studies that describe quality and health indicators of wild tea. The aim of this research was to evaluate the quality of wild and cultivated green tea from different regions of China: Wuzhishan, Baisha, Kunlushan, and Pu’Er. The assessment was carried out by verifying the concentration of selected chemical components in tea and relating it to the health risks they may pose, as well as to the nutritional requirements of adults. Wild tea was characterized by higher micronutrient concentration. The analyzed teas can constitute a valuable source of Mn in the diet. A higher concentration of nitrates and oxalates in cultivated tea can be associated with fertilizer use. The analyzed cultivated tea was a better source of antioxidants with a higher concentration of caffeine. There were no indications of health risks for wild or cultivated teas.  相似文献   

10.
Superparamagnetic iron oxide nanoparticles (SPIONs) are promising materials for various biomedical applications including targeted drug delivery and imaging, hyperthermia, magneto-transfections, gene therapy, stem cell tracking, molecular/cellular tracking, magnetic separation technologies (e.g. rapid DNA sequencing), and detection of liver and lymph node metastases. The most recent applications for SPIONs for early detection of inflammatory, cancer, diabetes and atherosclerosis have also increased their popularity in academia. In order to increase the efficacy of SPIONs in the desired applications, especial surface coating/characteristics are required. The aim of this article is to review the surface properties of magnetic nanoparticles upon synthesis and the surface engineering by different coatings. The biological aspects, cytotoxicity, and health risks are addressed. Special emphasis is given to organic and inorganic-based coatings due to their determinant role in biocompatibility or toxicity of the final particles.  相似文献   

11.
Capillary electrophoresis-mass spectrometry in food analysis   总被引:1,自引:0,他引:1  
Simó C  Barbas C  Cifuentes A 《Electrophoresis》2005,26(7-8):1306-1318
This work provides an updated overview (including works published till June 2004) on the principal applications of capillary electrophoresis-mass spectrometry (CE-MS) together with their main advantages and drawbacks in food science. Thus, analysis of amino acids, peptides, proteins, carbohydrates, or polyphenols by CE-MS in different foods is reviewed. Also, other natural compounds (e.g., alkaloids) and toxins analyzed by CE-MS in foods are revised. Moreover, exogenous substances with a potential risk for human health (e.g., pesticides, drugs) detected in foods by CE-MS are included in this work. The usefulness of CE-MS for food analysis and the information that this coupling can provide in terms of processing, composition, authenticity, quality, or safety of foods is also discussed.  相似文献   

12.
Dietary phytochemicals play an important role in the prevention and treatment of colon cancer. It is reported that group B of soyasaponin, derived from dietary pulses, has anti-colonic effects on some colon cancer cell lines. However, it is uncertain which specific soybean saponins play a role. In our study, as one of the group B soyasaponin, the anti-colon cancer activity of soyasaponins I (SsI) was screened, and we found that it had the inhibitory effect of proliferation on colon cancer cell lines HCT116 (IC50 = 161.4 μM) and LoVo (IC50 = 180.5 μM), but no effect on HT29 between 0–200 μM. Then, nine potential targets of SsI on colon cancer were obtained by network pharmacology analysis. A total of 45 differential metabolites were identified by metabolomics analysis, and the KEGG pathway was mainly enriched in the pathways related to the absorption and metabolism of amino acids. Finally, molecular docking analysis predicted that SsI might dock with the protein of DNMT1, ERK1. The results indicated that the effect of SsI on HCT116 might be exerted by influencing amino acid metabolism and the estrogen signaling pathway. This study may provide the possibility for the application of SsI against colon cancer.  相似文献   

13.
To evaluate the interactive effect of methylenetetrahydrofolate reductase (MTHFR) genotype and dietary factors on the development of breast cancer, a hospital based case-control study was conducted in South Korean study population consisting of 189 histologically confirmed incident breast cancer cases and their 189 age-matched controls without present or previous history of cancer. A PCR-RFLP method was used for the genotyping of MTHFR (C677T) and statistical evaluations were performed by unconditional logistic regression analysis. Consumption of some dietary factors, such as green vegetables (OR = 0.3, 95% CI: 0.2-0.6), white vegetables (OR = 0.3, 95% CI: 0.1-0.7) mushrooms (OR = 0.4, 95% CI: 0.3-0.7), and meats (OR = 1.7, 95% CI: 1.1-2.8) significantly decreased or increased the risk of breast cancer. Although the breast cancer risk was 1.7-fold (95% CI: 0.8-3.2) increased in women with MTHFR TT genotype, the association was not statistically significant. Women with MTHFR TT genotype and low green vegetable intake increased 5.6-fold (95% CI: 1.2-26.3) risk of breast cancer compared to high green vegetable intake group containing MTHFR CC/CT genotype. However, the interaction was not significant (p for interaction = 0.96). Our findings suggest that MTHFR polymorphism did not influence individual susceptibility to breast cancer. However MTHFR (C667T) genotype and green vegetable intakes appeared to have the interactive effect in breast cancer development.  相似文献   

14.
Sesame seeds are rich in lignan content and have been well-known for their health benefits. Unlike the other sesame lignan compounds (i.e., sesamin and sesamol), the study of the pharmacological activity of sesamolin has not been explored widely. This review, therefore, summarizes the information related to sesamolin’s pharmacological activities, and the mechanism of action. Moreover, the influence of its physicochemical properties on pharmacological activity is also discussed. Sesamolin possessed neuroprotective activity against hypoxia-induced reactive oxygen species (ROS) and oxidative stress in neuron cells by reducing the ROS and inhibiting apoptosis. In skin cancer, sesamolin exhibited antimelanogenesis by affecting the expression of the melanogenic enzymes. The anticancer activity of sesamolin based on antiproliferation and inhibition of migration was demonstrated in human colon cancer cells. In addition, treatment with sesamolin could stimulate immune cells to enhance the cytolytic activity to kill Burkitt’s lymphoma cells. However, the toxicity and safety of sesamolin have not been reported. And there is also less information on the experimental study in vivo. The limited aqueous solubility of sesamolin becomes the main problem, which affects its pharmacological activity in the in vitro experiment and clinical efficacy. Therefore, solubility enhancement is needed for further investigation and determination of its pharmacological activity profiles. Since there are fewer reports studying this issue, it could become a future prospective research opportunity.  相似文献   

15.
The study represents the first systematic risk assessment study in East Singhbhum district, Jharkhand, India for the safety of groundwater for drinking purpose with respect to metal(loid)s. The district is known for its mining and related activities. The results demonstrated that concentrations of the metal(loid)s showed significant spatial variation with Al, Mn, Fe, Ni and Zn exceeding the drinking water standards. Principal component analysis resulted in extraction of four factors explaining 76.3% of the data variability. The extracted principal components pointed towards both geogenic and anthropogenic activities governing the groundwater quality. Risk assessment was quantified by the hazard quotient (HQ) and cancer risk for both adult and child. The risk on human health posed by the metal(loid)s was found to be adverse for Mn with HQ > 1 for child. The chronic risks to the local population were largely contributed by Mn, Co and As. However, the carcinogenic risk for As was within the acceptable cancer risk value of 1 × 10?4. Considering the geometric mean of the metal(loid)s in the study area, the hazard index (HI) for adult was above unity. Considering all the locations, the HI varied from 0.23 to 13.03 and 0.20 to 11.15 for adult and child, respectively, suggesting that the groundwater is unsuitable for drinking without treatment at most of the locations.  相似文献   

16.
为了解重庆地区孕妇、婴儿及其母亲碘营养现状,给该地区实施科学补碘提供科学依据,采用砷铈催化分光光度法测定了当地水碘和孕妇、婴儿及其母亲的尿碘,电化学发光法检查了孕妇甲状腺功能.结果表明,水碘为5.99 μg/L,孕妇、乳母、婴儿尿碘中位数为203.80 μg/L、218.3 μg/L、288.4 μg/L,FT3、FT4为(3.94±0.59) pmol/L、(12.44±2.30) pmol/L;逐步回归分析表明,碘营养与文化程度、食用优质蛋白及富硒食品呈正相关,母亲缺碘是小孩缺碘的危险因素之一.提示特需人群的碘营养水平适宜,文化程度、食用优质蛋白及富硒食品为主要影响因素,婴儿尿碘与母亲相关.  相似文献   

17.
The biological activity of an in vitro digested infusion of Epilobium angustifolium (fireweed) was examined in a model system of intestinal epithelial and colon cancer tissues. The content of selected phenolic compounds in the digested aqueous extract of fireweed was determined using HPLC-ESI-QTOF-MS/MS. Biological activity was examined using the human colon adenocarcinoma cell lines HT-29 and CaCo-2 and the human colon epithelial cell line CCD 841 CoTr. Cytotoxicity was assessed by an MTT assay, a Neutral Red uptake assay, May-Grünwald-Giemsa staining, and a label-free Electric Cell-Substrate Impedance Sensing cytotoxicity assay. The effect of the infusion on the growth of selected intestinal bacteria was also examined. The extract inhibited the growth of intestinal cancer cells HT-29. This effect can be attributed to the activity of quercetin and kaempferol, which were the most abundant phenolic compounds found in the extract after in vitro digestion. The cytotoxicity of the fireweed infusion was dose-dependent. The highest decrease in proliferation (by almost 80%) compared to the control was observed in HT-29 line treated with the extract at a concentration of 250 μg/mL. The fireweed infusion did not affect the growth of beneficial intestinal bacteria, but it did significantly inhibit E. coli. The cytotoxic effect of the fireweed extract indicates that it does not lose its biological activity after in vitro digestion. It can be concluded that the fireweed infusion has the potential to be used as a supporting agent in colon cancer therapy.  相似文献   

18.
There is an increasing concern over the safety of engineered nanoparticles (ENPs) to humans and the environment and it is likely that the environmental risks of these particles will have to be tested under regulatory schemes such as REACH. Due to their unique properties and the fact that their detection and characterisation in complex matrices is challenging, existing analytical methods and test approaches for assessing environmental risk may not be appropriate for ENPs. In this article we discuss the challenges associated with the testing of ENPs to generate data on persistence, mobility, bioavailability and ecotoxicity in the environment. It is essential that careful consideration is given to the selection of the test material, the test system (including test vessels and study media) and the test exposure conditions. During a study it is critical that not only the concentration of the ENP is determined but also its characteristics (e.g. size, shape, degree of aggregation and dissolution). A range of analytical techniques is available including microscopy-based approaches (e.g transmission and scanning electron microscopy), dynamic light scattering, and size separation approaches (e.g. field flow fractionation and hydrodynamic chromatography) coupled to detection methods such as inductively coupled plasma MS. All of these have their disadvantages: some are unable to distinguish between ENPs and natural interferences; some techniques require sample preparation approaches that can introduce artefacts; and others are complex and time-consuming. A combination of techniques is therefore needed. Our knowledge in this area is still limited, and co-ordinated research is required to gain a better understanding of the factors and processes affecting ENP fate and effects in the environment as well as to develop more usable, robust and sensitive methods for characterisation and detection of ENPs in environmental systems.  相似文献   

19.
This review considers the recent literature in which animal models were used to investigate the purported health benefits of soy isoflavones. The main conclusions are that our animal models demonstrate minimal effects in breast, prostate, and colon cancer prevention, and that, while some cancers may respond to isoflavones, it would appear that isoflavones do not prevent further development once cancer has become established. Regarding cardiovascular health, the lipid-lowering effects of isoflavones have been established, but their efficacy may be less than original research purported. However, it may be considered a bonus of habitual soy consumption that blood cholesterol levels would be reduced somewhat. With respect to osteoporosis and menopausal symptoms, animal models do not show any consistent benefit of isoflavones in preventing osteoporosis, and calcium fortification or the use of prescribed medications are likely much better approaches to combat bone loss. However, our animal models of osteoporosis and menopausal symptoms may not be entirely representative of the human situation. Perhaps the benefit of isoflavones in cognitive skills and in delaying Alzheimer's disease is an area where they can be of some advantage. However, this field is very recent and requires much more research in both humans and animal models before any definitive benefit can be propounded. On the other hand, isoflavones in moderation are probably not dangerous, as few studies have indicated adverse effects. However, large doses have been shown to increase apoptosis and cell degeneration, and in some cancer regimes, once the cancer has progressed beyond the hormone-dependent stage, high doses of isoflavones may be contraindicated. The prospect of mega-dosing from isoflavone supplements opens a new chapter in the risk assessment of isoflavone consumption.  相似文献   

20.
Food allergies have become an important health issue especially in industrialized countries. Undeclared allergenic ingredients or the presence of “hidden” allergens because of contamination during the food production process pose great health risks to sensitised individuals. The EU directive for food labelling lists allergenic foods that have to be declared on food products by the manufacturers. The list includes gluten-containing cereals, crustaceans, eggs, fish, peanuts, soybeans, milk, various nuts (e.g. almond, hazelnut, and walnut, etc.), celery, mustard, sesame seeds, lupin, and molluscs. Reliable methods for detection and quantification of food allergens are needed that can be applied in a fast and easy-to-use manner, are portable, and need only limited technical equipment. This review focuses on the latest developments in food allergen analysis with special emphasis on fast immunoanalytical methods such as rapid enzyme-linked immunosorbent assays (ELISA), lateral-flow immunochromatographic assays (LFA) and dipstick tests. Emerging technologies such as immunochemical microarrays and biosensors are also discussed and their application to food allergen analysis is reviewed. Finally, a comprehensive overview of rapid immunochemical test kits that are currently available commercially is given in tabular form.  相似文献   

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