266 research outputs found
Alterations in lipid metabolism gene expression and abnormal lipid accumulation in fibroblast explants from giant axonal neuropathy patients
BACKGROUND: Giant axonal neuropathy (GAN) is a hereditary neurological disorder that affects both central and peripheral nerves. The main pathological hallmark of the disease is abnormal accumulations of intermediate filaments (IFs) in giant axons and other cell types. Mutations in the GAN gene, encoding gigaxonin, cause the disease. Gigaxonin is important in controlling protein degradation via the ubiquitin-proteasome system. The goal of this study was to examine global alterations in gene expression in fibroblasts derived from newly identified GAN families compared with normal cells. RESULTS: We report the characterization of fibroblast explants obtained from two unrelated GAN patients. We identify three novel putative mutant GAN alleles and show aggregation of vimentin IFs in these fibroblasts. By microarray analysis, we also demonstrate that the expression of lipid metabolism genes of the GAN fibroblasts is disrupted, which may account for the abnormal accumulations of lipid droplets in these cells. CONCLUSION: Our findings suggest that aberrant lipid metabolism in GAN patients may contribute to the progression of the disease
Global population structure and evolution of Bordetella pertussis and their relationship with vaccination.
Bordetella pertussis causes pertussis, a respiratory disease that is most severe for infants. Vaccination was introduced in the 1950s, and in recent years, a resurgence of disease was observed worldwide, with significant mortality in infants. Possible causes for this include the switch from whole-cell vaccines (WCVs) to less effective acellular vaccines (ACVs), waning immunity, and pathogen adaptation. Pathogen adaptation is suggested by antigenic divergence between vaccine strains and circulating strains and by the emergence of strains with increased pertussis toxin production. We applied comparative genomics to a worldwide collection of 343 B. pertussis strains isolated between 1920 and 2010. The global phylogeny showed two deep branches; the largest of these contained 98% of all strains, and its expansion correlated temporally with the first descriptions of pertussis outbreaks in Europe in the 16th century. We found little evidence of recent geographical clustering of the strains within this lineage, suggesting rapid strain flow between countries. We observed that changes in genes encoding proteins implicated in protective immunity that are included in ACVs occurred after the introduction of WCVs but before the switch to ACVs. Furthermore, our analyses consistently suggested that virulence-associated genes and genes coding for surface-exposed proteins were involved in adaptation. However, many of the putative adaptive loci identified have a physiological role, and further studies of these loci may reveal less obvious ways in which B. pertussis and the host interact. This work provides insight into ways in which pathogens may adapt to vaccination and suggests ways to improve pertussis vaccines. IMPORTANCE Whooping cough is mainly caused by Bordetella pertussis, and current vaccines are targeted against this organism. Recently, there have been increasing outbreaks of whooping cough, even where vaccine coverage is high. Analysis of the genomes of 343 B. pertussis isolates from around the world over the last 100 years suggests that the organism has emerged within the last 500 years, consistent with historical records. We show that global transmission of new strains is very rapid and that the worldwide population of B. pertussis is evolving in response to vaccine introduction, potentially enabling vaccine escape
No Interactions of Stacked Bt Maize with the Non-target Aphid Rhopalosiphum padi and the Spider Mite Tetranychus urticae
In the agroecosystem, genetically engineered plants producing insecticidal Cry proteins from Bacillus thuringiensis (Bt) interact with non-target herbivores and other elements of the food web. Stacked Bt crops expose herbivores to multiple Cry proteins simultaneously. In this study, the direct interactions between SmartStax® Bt maize producing six different Cry proteins and two herbivores with different feeding modes were investigated. Feeding on leaves of Bt maize had no effects on development time, fecundity, or longevity of the aphid Rhopalosiphum padi (Hemiptera: Aphididae), and no effects on the egg hatching time, development time, sex ratio, fecundity, and survival of the spider mite Tetranychus urticae (Acari: Tetranychidae). The results thus confirm the lack of effects on those species reported previously for some of the individual Cry proteins. In the Bt maize leaves, herbivore infestation did not result in a consistent change of Cry protein concentrations. However, occasional statistical differences between infested and non-infested leaves were observed for some Cry proteins and experimental repetitions. Overall, the study provides evidence that the Cry proteins in stacked Bt maize do not interact with two common non-target herbivores
No Interactions of Stacked Bt Maize with the Non-target Aphid Rhopalosiphum padi and the Spider Mite Tetranychus urticae
Mobilization of Au and Ag during Supergene Processes in the Linglong Gold Deposit: Evidence from SEM and LA–ICP–MS Analyses of Sulfides
Precious metals can be mobilized during supergene processes, which are important for the formation of high-grade or high-purity ores. The world-class Linglong gold deposit has high-grade ores that have undergone supergene processes in the near-surface zone. Under which conditions the supergene modification occurred and how Au and Ag behaved during the supergene processes have been poorly studied in this deposit. Here, we performed scanning electron microscope (SEM) and laser ablation–inductively coupled plasma–mass spectrometry (LA–ICP–MS) analyses on samples from the supergene enrichment zone of the Linglong gold deposit. The results show that secondary minerals were formed sequentially from magnetite-goethite-limonite to marcasite-acanthite, and finally to siderite after the primary minerals of pyrite-pyrrhotite-chalcopyrite. These mineral assemblages and variations indicate that the supergene modification by groundwater occurred under oxidative and weakly acidic conditions in the near-surface zone and evolved to reductive and near neutral conditions in the supergene enrichment zone. The newly formed marcasite has much higher Au (0.003–23.5 ppm, mean of 1.33 ppm) and Ag (81.7–6021 ppm, mean of 1111 ppm) concentrations than those of the primary pyrite (Au of 0.004–0.029 ppm and Ag of 0.22–4.14 ppm), which together with the formation of independent Ag–S mineral (acanthite), indicates that Au and Ag were significantly mobilized and fractionated during the supergene processes. These processes improved the Au and Ag grades in the supergene enrichment zone and thus facilitate their extraction
Data from: Stacked Bt maize and arthropod predators – exposure to insecticidal Cry proteins and potential hazards
Genetically engineered (GE) crops with stacked insecticidal traits expose arthropods to multiple Cry proteins from Bacillus thuringiensis (Bt). One concern is that the different Cry proteins may interact and lead to unexpected adverse effects on non-target species. Bi- and tri-trophic experiments with SmartStax maize, herbivorous spider mites (Tetranychus urticae) and aphids (Rhopalosiphum padi), and predatory spiders (Phylloneta impressa), ladybeetles (Harmonia axyridis), and lacewings (Chrysoperla carnea) were conducted. Cry1A.105, Cry1F, Cry3Bb1, and Cry34Ab1 moved in a similar pattern through the arthropod food chain. In contrast, Cry2Ab2 had highest concentrations in maize leaves, but lowest in pollen, and lowest acquisition rates by herbivores and predators. While spider mites contained Cry protein concentrations exceeding the values in leaves (except Cry2Ab2), aphids contained only traces of any Cry protein. Predators contained lower concentrations than their food. Among the different predators, ladybeetle larvae showed higher concentrations than lacewing larvae and juvenile spiders. Acute effects of SmartStax maize on predator survival, development, and weight were not observed. The study thus provides evidence that the different Cry proteins do not interact in a way that poses a risk to the investigated non-target species under controlled laboratory conditions
Data from: Stacked Bt maize and arthropod predators: exposure to insecticidal Cry proteins and potential hazards
Weight, development, and survival data for Phylloneta impressa juvenile spiders, Chrysoperla carnea lacewing larvae, and Harmonia axyridis ladybeetle larvae fed with pollen, aphids Rhopalosiphum padi, or spider mites Tetranychus urticae from SmartStax Bt maize or genetically closest non-Bt hybrid. ELISA Cry protein measurements of the previously described predators as well as of food items and maize leaves
Effects of Exogenous Salicylic Acid Application to Aboveground Part on the Defense Responses in Bt (Bacillus thuringiensis) and Non-Bt Corn (Zea mays L.) Seedlings
Bt (Bacillus thuringiensis) corn is one of the top three large-scale commercialized anti-insect transgenic crops around the world. In the present study, we tested the Bt protein content, defense chemicals contents, and defense enzyme activities in both the leaves and roots of Bt corn varieties 5422Bt1 and 5422CBCL, as well as their conventional corn 5422 seedlings, with two fully expanded leaves which had been treated with 2.5 mM exogenous salicylic acid (SA) to the aboveground part for 24 h. The result showed that the SA treatment to the aboveground part could significantly increase the polyphenol oxidase activity of conventional corn 5422, the Bt protein content, and peroxidase activities of Bt corn 5422Bt1, as well as the polyphenol oxidase and peroxidase activity of Bt corn 5422CBCL in the leaves. In the roots, the polyphenol oxidase and peroxidase activity of conventional corn 5422, the polyphenol oxidase and superoxide dismutase activities of Bt corn 5422Bt1, the DIMBOA (2,4-dihydroxy-7-methoxy-2H, 1, 4-benzoxazin-3 (4H)-one) content, and four defense enzymes activities of Bt corn 5422CBCL were systematically increased. These findings suggest that the direct effect of SA application to aboveground part on the leaf defense responses in Bt corn 5422CBCL is stronger than that in non-Bt corn. Meanwhile, the systemic effect of SA on the root defense responses in Bt corn 5422CBCL is stronger than that in conventional corn 5422 and Bt corn 5422Bt1. It can be concluded that the Bt gene introduction and endogenous chemical defense responses of corns act synergistically during the SA-induced defense processes to the aboveground part. Different transformation events affected the root defense response when the SA treatment was applied to the aboveground part
Recent trends and advances in the epidemiology, synergism, and delivery system of lycopene as an anti-cancer agent
Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGDietary interventions are key nutritional strategies to prevent, improve, and prolong the survival of cancer patients. Lycopene, one of the strongest natural antioxidants, and its biologically active metabolites, have shown significant potential to prevent a variety of cancers, including prostate, breast, and stomach cancers, making it a promising anti-cancer agent. We review the potential regulatory mechanisms and epidemiological evidences of lycopene and its metabolites to delay the progression of cancers at different developmental stages. Recent studies have revealed that lycopene and its metabolites mediate multiple molecular mechanisms in cancer treatment such as redox homeostasis, selective anti-proliferation, apoptosis, anti-angiogenesis, tumour microenvironment regulation, and anti-metastasis and anti-invasion. Gut microbes and cholesterol metabolism are also the potential regulation targets of lycopene and its metabolites. As a dietary supplement, the synergistic interaction of lycopene with other drugs and nutrients is highlighted especially due to its binding activity with other nutrients in the diet found central to the fight against cancer. Furthermore, the application of several of novel lycopene delivery carriers are on the rise including nanoemulsions, nanostructured liposomes, and polymer nanoparticles for cancer prevention as discussed in this review with future needed development. Moreover, the synergistic mechanism between lycopene and other nutrients or drugs and novel delivery systems of lycopene should now be deeply investigated to improve its clinical application in cancer intervention in the future
- …