Search Results for: DNA

Abstract: The history of this book is closely related to the origins of the international biosafety course ‘Holistic Foundations for Assessment and Regulation of Genetic Engineering and Genetically Modified Organisms’. It started at a breakfast conversation between the Third World Network (TWN) director Martin Khor, TWN’s coordinator of its environment programme Chee Yoke Ling, and …

Abstract: A field in which Brassica napus volunteers were not controlled by several applications of glyphosate was investigated in 1998. This field had been planted with glufosinate-resistant and imidazolinone-resistant B. napus in 1997 and was adjacent to a field that had grown glyphosate-resistant B. napus. Mature volunteer B. napus were collected on a 50- by …

Abstract: Transgene integration into plant genomes is a complex process accompanied by molecular rearrangements. Classic methods that are normally used to study transgenic population genetics are generally inadequate for assessing such integration. Two major characteristics of transgenic populations are that a transgenic genome may harbor many copies of the transgene and that molecular rearrangements can …

Abstract: Samples of rice from Mexican and USA retail stores were analyzed for the presence of transgenic (GM) events using real-time PCR. In screening for the CaMV35S promoter sequence (35SP), positive results were found in 49 and 35% of the Mexican and American samples, respectively. In further investigations in Mexican samples, 43% were positive for …

Abstract: 研究目的： 通过GC.1小鼠精原细胞体外试验及小鼠精子畸形体内试验,探讨农达对雄性生殖细胞的毒性作用及其可能作用机制。 研究方法： GC-1小鼠精原细胞体外试验：以GC-1细胞为受试细胞,通过MTT试验筛选农达染毒浓度及NAC干预浓度。其后续试验中NAC干预浓度为101μmol／L,预处理1h,农达染毒浓度定为60、90、120、150、180mg／L,染毒时间为24h。将GC-1细胞随机分成对照组(第1组)、农达染毒组(第2-6组)、10mmol／L NAC+90 mg／L农达染毒干预组(第7组)。GC-1细胞的形态学改变,采用姬母萨染色法在光镜下观察；农达对GC-1细胞膜通透性影响和细胞毒性作用采用乳酸脱氢酶(LDH)活性水平结合台盼蓝拒染法评价；农达诱导GC-1细胞氧化损伤程度选用超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽(GSH)含量指标评价；用彗星实验检测细胞DNA损伤。 小鼠精子畸形体内试验：将100只昆明种雄性小鼠随机分为5组(每组20只),即290mg／kg、580mg／kg、1160mg／kg农达染毒组、1个阴性对照组和1个阳性对照组。各染毒组和阴性对照组采用灌胃给药,阳性对照组采用腹腔注射,连续给药5天,将动物于给药第7、28、35天分三批处死,观察睾丸、附睾重量及其脏器系数,分析精子数和精子畸形率的变化。 结果： GC-1小鼠精原细胞体外试验： 1、农达在60-180mg／L处理浓度范围内,能明显引起GC-1细胞存活率的降低(P0.05),处理浓度和细胞存活率之间存在负相关(r=-0.992,p0.01)。 2、农达在60-180mg／L处理浓度范围内,引起GC-1细胞皱缩或肿大,染色质浓染,细胞间隙扩大,空泡样变。随着农达浓度的增加变化明显,细胞密度也明显减少,细胞膜和核膜不完整或消失,染色质嗜碱性降低。加入NAC有保护作用。 3、农达在90-180mg／L处理浓度范围内,引起细胞培养上清液中LDH活性增加(p0.05),台盼蓝染色实验表明农达引起细胞膜受损率增加(p0.05),NAC能减少细胞毒性。 4、农达在60-180mg／L处理浓度范围内,能明显诱导细胞DNA的链断裂,剂量越高,DNA断裂程度越严重,彗星率越高(P0.05)；NAC+90mg／L处理组,与90mg／L处理组相比DNA损伤程度减轻(P0.05)。 5、农达在60-180mg／L处理浓度范围内,随染毒剂量增大,MDA生成增多SOD、GSH活性明显降低,与对照组比较差异有显著性(P0.05)；加入NAC后有明显保护作用(P0.05)。 小鼠精子畸形体内试验： 1、与阴性对照组比较,580mg／kg、1160mg／kg农达剂量组可使小鼠精子数目明显减少(p0.05)、精子畸形率明显增加(p0.05)。 2、与阴性对照组比较,1160mg／kg农达剂量组在染毒后早期可引起附睾重量和附睾系数下降,在染毒后晚期引起附睾和睾丸重量减轻,睾丸系数下降(p0.05)。 结论： 农达在60mg／L-180mg／L范围内,能引起GC-1细胞存活率下降,LDH活性增加,MDA生成增多、GSH和SOD活性降低以及DNA损伤,使细胞产生凋亡和坏死,对细胞具有明显的损伤作用；加入抗氧化剂NAC预处理后具有相应的拮抗作用。提示其损伤的作用机制可能与农达导致GC-1细胞氧化与抗氧化失衡、破坏细胞膜通透性,引起细胞氧化损伤和DNA损害等途径有关。 580mg／kg和1160mg／kg的农达剂量组可引起小鼠精子数目减少、精子畸形率增加,以及附睾和睾丸重量及其系数下降,提示农达对雄性小鼠具有明显的生殖毒性作用。 Keywords: Roundup, Toxic Effects, Male Germ Cells, Mouse Sperm Abnormality, In Vitro Test, Morphological Changes, Cytotoxicity, Survival Rate, Cell Survival, Chromatin Staining, Cell Gap Expansion, Vacuolization, DNA Strand Breakage, Sperm Abnormality, Sperm Count Citation: …

Abstract: Eleusine indica is one of the most common weed species found in agricultural land worldwide. Although herbicide-glyphosate provides good control of the weed, its frequent uses has led to abundant reported cases of resistance. Hence, the development of genetic markers for quick detection of glyphosate-resistance in E. indica population is imperative for the control …

Abstract: Consumer response to genetically altered foods has been mixed in the United States. While transgenic crops have entered the food supply with little comment, other foods, such as the bioengineered tomato, have caused considerable controversy. Objections to genetically engineered food are varied, ranging from the religious to the aesthetic. One need not endorse these …

Text: One of the communication tools of the EC-funded Biosafenet project is a series of six Biosafenet Seminars that will be held 2007–2009. Their purpose is to convene small groups of scientists to consider emerging issues related to the potential impact of genetically modified organisms (GMOs). The first Seminar was organized by the ICGEB at …

Abstract: This synopsis reviews published in vivo studies on possible health consequences of genetically modified food and feed where the ingredients in question have consisted of genetically modified plant materials. The following, however, have not been taken into consideration:–ingredients consisting of genetically modified microorganisms or parts of animals/fish–ingredients produced by/from genetically modified organisms but without …

Abstract: The causal link between GM food and human health is proposed to be the scrambling of genes in DNA by low-level UV radiation. GM stands for genetically modified. Modern agriculture controls weeds by spraying Roundup containing water and Glyphosate onto crop fields. To enhance Glyphosate penetration through weed leaves, the adjuvant POEA is added …

Abstract: The genotoxicity of pesticides is an issue of worldwide concern. The present study was undertaken to evaluate the genotoxic potential of a widely used herbicide formulation, Roundup (glyphosate), in erythrocytes of broad-snouted caiman (Caiman latirostris) after in ovo exposure. Caiman embryos were exposed at early embryonic stage to different sub-lethal concentrations of Roundup (50, …

Abstract: In South America, economic interests in last years have produced a constant increase in transgenic soybean cropping, with the corresponding rise in pesticide formulated products. The aim of this study was to determine the effects of pesticides formulations and mixtures on a South American caiman, Caiman latirostris, after in ovo exposure. We conducted a …

Abstract: Multiple variants of the Cauliflower mosaic virus 35S promoter (P35S) are used to drive the expression of transgenes in genetically modified plants, for both research purposes and commercial applications. The genetic organization of the densely packed genome of this virus results in sequence overlap between P35S and viral gene VI, encoding the multifunctional P6 …

Abstract: Glyphosate-based products are the leading post-emergent agricultural herbicides in the world, particularly in association with glyphosate tolerant crops. However, studies on the effects of glyphosate-based formulations on terrestrial receptors are scarce. This study was conducted to evaluate the comparative toxicity of two glyphosate-based products: Roundup FG (monoammonium salt, 72% acid equivalent, glyphosate-A) and Mon …

Abstract: A possible consequence of planting genetically modified organisms (GMOs) in centres of crop origin is unintended gene flow into traditional landraces. In 2001, a study reported the presence of the transgenic 35S promoter in maize landraces sampled in 2000 from the Sierra Juarez of Oaxaca, Mexico. Analysis of a large sample taken from the …

Abstract: So far, relatively few genetically modified plants (GMPs) have been planted in the European Union (EU). However, in France, seed batches weakly contaminated by unidentified GM materials have recently been detected among commercial maize seeds (14 seed batches positive out of 447 analyzed). We have developed a 3-step approach to precisely identify the genetic …

Abstract: Seasonal variation in the response of riverine microbial communities to an environmentally relevant exposure to glyphosate (about 10 μg l−1) was assessed on natural communities collected in spring and summer, using two 14-day microcosm studies. The two experiments showed no major effect of glyphosate on algal biomass (chlorophyll a concentrations), bacterial activity ([3H]thymidine incorporation), …

Abstract: Evolved resistance to the herbicide glyphosate has been reported in eleven weed species, including Lolium multiflorum. Two glyphosate-resistant L. multiflorum populations were collected, one from Chile (SF) and one from Oregon, USA (OR), and the mechanisms conferring glyphosate resistance were studied. Based on a Petri dish dose–response bioassay, the OR and the SF populations …

Abstract: Microprojectile bombardment to deliver DNA into plant cells represents a major breakthrough in the development of plant transformation technologies and accordingly has resulted in transformation of numerous species considered recalcitrant to Agrobacterium- or protoplast-mediated transformation methods. This article attempts to review the current understanding of the molecular and genetic behavior of transgenes introduced by …

Abstract: Endometriosis is an oestrogen-dependant inflammatory disease affecting 10 % of reproductive-aged women. Often accompanied by chronic pelvic pain and infertility, endometriosis rigorously interferes with women’s quality of life. Although the pathophysiology of endometriosis remains unclear, a growing body of evidence points to the implication of environmental toxicants. Over the last decade, an increase in …

Abstract: Many food and feed additives result from fermentation of genetically modified (GM) microorganisms. For vitamin B2 (riboflavin), GM Bacillus subtilis production strains have been developed and are often used. The presence of neither the GM strain nor its recombinant DNA is allowed for fermentation products placed on the EU market as food or feed …

Abstract: Daphnia magna is a widely used model organism for aquatic toxicity testing. In the present study, the authors investigated the hydrolytic enzyme activity of D. magna after exposure to toxicant stress. In vivo enzyme activity was quantified using 15 fluorogenic enzyme probes based on 4‐methylumbelliferyl or 7‐amino‐4‐methylcoumarin. Probing D. magna enzyme activity was evaluated …

Abstract: Genetically modified (GM) food crops are considered to have the potential of providing food security especially in developing countries. Scientists have raised concern over the hazards associated with the consumption of genetically modified organisms (GMOs). One of these hazards, which have great controversy reports, is the possible horizontal gene transfer from GM-food or feed …

Abstract: This work was conducted in the context of postmarketing biosafety assessment of genetically modified products. It presents a systematic approach based on a chronic toxicity study on Wistar albino rats, with a range of combined parameters including biochemical, histopathological, and cytogenetic to evaluate the negative impact of a genetically modified (GM) diet on animal …

Abstract: Interspecific hybridization is a route for transgenes from genetically modified (GM) animals to invade wild populations, yet the ecological effects and potential risks that may emerge from such hybridization are unknown. Through experimental crosses, we demonstrate transmission of a growth hormone transgene via hybridization between a candidate for commercial aquaculture production, GM Atlantic salmon …