PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Plant Variety Protection Act”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed2004

The establishment of 'essential derivation' among rose varieties, using AFLP.

In the International Union for the Protection of New Varieties of Plants Act of 1991, mutation is mentioned as one of the mechanisms to obtain an 'essentially derived' variety (EDV). For the implementation of the EDV concept in the case of mutation, it is important that the level of genetic relatedness between an initial variety and derived mutant varieties can clearly be distinguished from the level of relatedness between arbitrary pairs of varieties without a derivation relation. Conditions to be fulfilled for such a distinction include enough genetic differentiation in the germplasm pool of interest, sufficiently low levels of genomic sampling error and technical laboratory error and high reproducibility within and between laboratories. In rose, mutants or 'sports' are frequently observed during multiplication, making it a suitable crop for studying the possibilities for introduction of the EDV concept in ornamentals. We studied genetic similarities among 83 rose varieties, including 13 mutant groups. Twelve AFLP primer combinations generated 284 polymorphic markers and 114 monomorphic (fixed) bands. Pair-wise Jaccard similarities between original varieties and derived mutants were close to 1.0 (>0.96), whereas all similarities between original varieties were below 0.80, with 75% of the non-mutant similarities even being below 0.50. Values less than 1.0 for similarity among original varieties and their mutants were to a major extent due to scoring errors. Error rates in automated scoring proved to be lower than those in manually scored and transferred data. Experimental errors, even between laboratories, turned out to be very small. On the basis of a consistent and large difference between similarities, relations between an original variety and its mutants can easily be identified and distinguished from relations between original varieties. These results open the way for implementing the essential derivation concept in rose.

Breeding↗
PubMed2006

Protective effect of selected flavonoids on in vitro daunorubicin-induced cardiotoxicity.

Flavonoids are an ubiquitous group of polyphenolic substances with varied chemical structures present in foods of plant origin and act as free radical scavenging and chelating agents with a variety of biological activities. Using a model of spontaneously beating, cultured adult rat cardiomyocytes, this study examined the cardioprotective role of quercetin, naringenin, pycnogenol and a model antioxidant, trolox, against daunorubicin-induced toxicity. Cardiomyocyte protection was assessed by MTT test and extracellular lactate dehydrogenase detection. Protection of cardiomyocytes was concentration/dose dependent for quercetin > naringenin > pycnogenol > trolox. Quercetin (10(-4)-10(-6) mol/L) after 24 h of co-incubation with daunorubicin significantly increased the cardiomyocyte survival in all tested concentrations (p < 0.001). The cytoprotective effect of naringenin (10(-4)-10(-6) mol/L) was similar to those of quercetin (p < 0.001 and p < 0.01, respectively). Pycnogenol was the least effective of the flavonoids studied. On the other hand, all tested flavonoids had significantly better protective effects than trolox. The leakage of lactate dehydrogenase induced by daunorubicin was also prevented by the studied compounds and was in accordance with their cytoprotective activity.

Animals↗
PubMed2003

Releases from copper smelters and refineries and zinc plants in Canada: human health exposure and risk characterization.

In these assessments of releases from copper smelters and refineries and from zinc plants as Priority Substances under the Canadian Environmental Protection Act (CEPA), available data were critically evaluated to determine if environmental exposure to selected components of these releases poses a risk to human health. The data on airborne levels of a variety of toxic substances near these facilities in Canada were obtained from the companies or provinces and systematically analyzed. Monitoring of ambient air near the Canadian copper smelters and refineries and zinc plants indicates that releases from these facilities result in increased potential for inhalation exposure of local human populations to several components of releases (As, Cd, Cr, Ni, Pb, SO(2) and PM(10)). Airborne levels in the vicinity of these metal-processing operations overlap those associated with cardiorespiratory effects for PM(10), and exceed health-based guidelines for SO(2) and, near some facilities, Pb. In addition, the margin between levels of As, Cd, Cr and Ni near these facilities in Canada and carcinogenic potency for each of these metals is relatively small near copper smelters, larger near copper refineries, and intermediate near zinc plants. On this basis, the risk to human health from environmental exposure to releases from these facilities is considered to be high compared with other Priority Substances assessed under CEPA, especially for facilities where copper is smelted.

Air Pollutants↗
PubMed2005

Proposed criteria for assessing the efficacy of cancer reduction by plant foods enriched in carotenoids, glucosinolates, polyphenols and selenocompounds.

BACKGROUND AND AIMS: The cancer-protective properties of vegetable consumption are most likely mediated through 'bioactive compounds' that induce a variety of physiologic functions including acting as direct or indirect antioxidants, regulating enzymes and controlling apoptosis and the cell cycle. The 'functional food' industry has produced and marketed foods enriched with bioactive compounds, but there are no universally accepted criteria for judging efficacy of the compounds or enriched foods. SCOPE: Carotenoids, glucosinolates, polyphenols and selenocompounds are families of bioactive compounds common to vegetables. Although numerous studies have investigated the agricultural and human health implications of enriching foods with one or more of these compounds, inadequate chemical identification of compounds, lack of relevant endpoints and inconsistencies in mechanistic hypotheses and experimental methodologies leave many critical gaps in our understanding of the benefits of such compounds. This review proposes a decision-making process for determining whether there is reasonable evidence of efficacy for the both the compound and the enriched food. These criteria have been used to judge the evidence of efficacy for cancer prevention by carotenoids, polyphenols, glucosinolates and selenocompounds. CONCLUSIONS: The evidence of efficacy is weak for carotenoids and polyphenols; the evidence is stronger for glucosinolates and lycopene, but production of enriched foods still is premature. Additionally there is unacceptable variability in the amount and chemical form of these compounds in plants. The evidence of efficacy for selenocompounds is strong, but the clinical study that is potentially the most convincing is still in progress; also the variability in amount and chemical form of Se in plants is a problem. These gaps in understanding bioactive compounds and their health benefits should not serve to reduce research interest but should, instead, encourage plant and nutritional scientists to work together to develop strategies for improvement of health through food.

Animals↗
PubMed2004

In situ and in vitro antioxidant activity of sweetpotato anthocyanins.

Anthocyanins from a variety of fruits and vegetables have been shown to possess potent antioxidant activity in vitro, but scavenging of free radicals by anthocyanins has only been demonstrated in situ in the leaves of certain plants. We report on a new sweetpotato that exhibits mottled purple flesh attributable to high concentrations of anthocyanins. By perfusing transverse sweetpotato sections with the reactive oxygen species H(2)O(2), followed by the H(2)O(2) sensitive fluorochrome scopletin, we show that anthocyanins act as antioxidants in situ within the sweetpotato storage roots. We also demonstrate in vitro antioxidant activity by sweetpotato anthocyanins, where an additive effect with hydroxycinnamic acids is observed. Anthocyanic foods have been shown to offer protection against a variety of degenerative disease processes. Given that sweetpotato can be eaten several hundred grams at a time and as a staple, these data are consistent with the possibility of superior health protection by anthocyanic varieties of sweetpotato in comparison to most common fruits and vegetables.

Anthocyanins↗
PubMed2004

New approaches to the role of diet in the prevention of cancers of the alimentary tract.

Cancers of the alimentary tract are, collectively, amongst the major causes of morbidity and deaths from cancer across the world today. Of the 10 million new cases of cancer diagnosed in 2000, about 2.3 million were cancers of the pharynx, oesophagus, stomach or colorectum. Nevertheless, epidemiological studies indicate that cancers of the digestive organs are also amongst the most susceptible to modification by dietary factors. International variations in incidence suggest that round three quarters of all sporadic colorectal cancers are attributable to diet. Even within the relatively uniform environment of the European Union, there are variations in the incidence of colorectal and oesophageal cancers of about two- and six-fold, respectively. Carcinomas of the alimentary tract arise from epithelial cells via distinct sequences of neoplastic change, which require a large fraction of an individual's lifespan. The best characterised of these is the adenoma-carcinoma sequence of colorectal carcinogenesis, in which progressive loss of differentiation and normal morphology in a growing lesion is associated with the acquisition of somatic mutations, and of aberrant methylation of CpG-islands, leading to gene silencing. These molecular events are accompanied by functional changes, including increased mitosis and evasion of apoptosis. There is little evidence that diet exerts its effects primarily through food-borne carcinogens that can be identified and eliminated from the food-chain. It is far more probable that the adverse effects of diet are caused largely by over-consumption of energy, coupled with inadequate intakes of protective substances, including micronutrients, dietary fibre and a variety of phytochemicals. The latter are biologically active secondary plant metabolites, many of which modify cell proliferation and induce apoptosis in vitro. There is growing evidence that such effects also occur in vivo, and that they can suppress the progress of neoplasia. Carcinomas of the oesophagus, stomach and colon all appear to be partially preventable by diets rich in fruits and vegetables. Plant foods contain a variety of components including micronutrients, polyunsaturated fatty acids, and secondary metabolites such as glucosinolates and flavonoids, many of which can inhibit cell proliferation and induce apoptosis, and which may well act synergistically when combined in the human diet. The future challenge is to fully characterise and evaluate these effects at the cellular and molecular level, so at to exploit their full potential as protective mechanisms for the population as a whole.

Anticarcinogenic Agents↗
PubMed1985

Suppression of cholesterogenesis by plant constituents: review of Wisconsin contributions to NC-167.

In animals, non-sterol metabolites of the mevalonate pathway act independently from receptor-mediated cholesterol uptake in the multivalent feedback regulation of mevalonate biosynthesis. Studies leading to the isolation and characterization of plant-borne suppressors of mevalonate biosynthesis are reviewed. We propose that one cardio-protective component of the vegetarian diet consists of a variety of non-sterol, post-mevalonate metabolites. These products of plant branches of the mevalonate pathway, discarded as animals evolved, continue to influence animal sterol metabolism. It is through this action, we propose, that the cholesterol-suppressive action of plant materials is expressed.

Animals↗
PubMed2000

Ice nucleation and antinucleation in nature.

Plants and ectothermic animals use a variety of substances and mechanisms to survive exposure to subfreezing temperatures. Proteinaceous ice nucleators trigger freezing at high subzero temperatures, either to provide cold protection from released heat of fusion or to establish a protective extracellular freezing in freeze-tolerant species. Freeze-avoiding species increase their supercooling potential by removing ice nucleators and accumulating polyols. Terrestrial invertebrates and polar marine fish stabilize their supercooled state by means of noncolligatively acting antifreeze proteins. Some organisms also depress their body fluid melting point to ambient temperature by evaporation and/or solute accumulation.

Acclimatization↗
PubMedDate not supplied

The antitumor activities of flavonoids.

The flavonoids are polyphenolic compounds found as integral components of the human diet. They are universally present as constituents of flowering plants, particularly of food plants. The flavonoids are phenyl substituted chromones (benzopyran derivatives) consisting of a 15-carbon basic skeleton (C6-C3-C6), composed of a chroman (C6-C3) nucleus (the benzo ring A and the heterocyclic ring C), also shared by the tocopherols, with a phenyl (the aromatic ring B) substitution usually at the 2-position. Different substitutions can typically occur in the rings, A and B. Several plants and spices containing flavonoid derivatives have found application as disease preventive and therapeutic agents in traditional medicine in Asia for thousands of years. The selection of a particular food plant, plant tissue or herb for its potential health benefits appears to mirror its flavonoid composition. The much lower risk of colon, prostate and breast cancers in Asians, who consume more vegetables, fruits and tea than populations in the Western hemisphere do, raises the question of whether flavonoid components mediate the protective effects of diets rich in these foodstuffs by acting as natural chemopreventive and anticancer agents. An impressive body of information exists on the antitumor action of plantflavonoids. In vitro work has concentrated on the direct and indirect actions of flavonoids on tumor cells, and has found a variety of anticancer effects such as cell growth and kinase activity inhibition, apoptosis induction, suppression of the secretion of matrix metalloproteinases and of tumor invasive behavior. Furthermore, some studies have reported the impairment of in vivo angiogenesis by dietary flavonoids. Experimental animal studies indicate that certain dietary flavonoids possess antitumor activity. The hydroxylation pattern of the B ring of the flavones and flavonols, such as luteolin and quercetin, seems to critically influence their activities, especially the inhibition of protein kinase activity and antiproliferation. The different mechanisms underlying the potential anticancer action of plant flavonoids await further elucidation. Certain dietary flavonols and flavones targeting cell surface signal transduction enzymes, such as protein tyrosine and focal adhesion kinases, and the processes of angiogenesis appear to be promising candidates as anticancer agents. Further in vivo studies of these bioactive constituents is deemed necessary in order to develop flavonoid-based anticancer strategies. In view of the increasing interest in the association between dietary flavonoids and cancer initiation and progression, this important field is likely to witness expanded effort and to attract and stimulate further vigorous investigations.

Animals↗
PubMed2002

Analysis of flour and food samples for cry9C from bioengineered corn.

StarLink corn is a variety of yellow corn that has been genetically modified by the insertion of an altered cry9C gene into the plant genome. resulting in expression of the insecticidal Cry9C protein. The U.S. Environmental Protection Agency has approved StarLink corn for use in animal feed but not in food intended for human consumption. Therefore, under the U.S. Food, Drug, and Cosmetic Act, any food intended for human consumption in which the presence of StarLink corn is indicated by the presence of either the Cry9C protein or the cry9C gene would be considered adulterated. Extraction and PCR-based methods were used to detect the presence of the cry9C DNA initially in corn flour and corn meal, and then these methods were extended to the analysis of processed corn products, including taco shells, cereals, baby foods, party snacks, and chips, for the presence of this modified genetic material. In a survey of 63 products, the cry9C transgene was detected in 4 taco shells.

Bacillus thuringiensis Toxins↗