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991.
Jim Kaput Chris T. Evelo Giuditta Perozzi Ben van Ommen Richard Cotton 《Genes & nutrition》2010,5(4):275-283
Nutrigenomics is the science of analyzing and understanding gene–nutrient interactions, which because of the genetic heterogeneity, varying degrees of interaction among gene products, and the environmental diversity is a complex science. Although much knowledge of human diversity has been accumulated, estimates suggest that ~90% of genetic variation has not yet been characterized. Identification of the DNA sequence variants that contribute to nutrition-related disease risk is essential for developing a better understanding of the complex causes of disease in humans, including nutrition-related disease. The Human Variome Project (HVP; http://www.humanvariomeproject.org/) is an international effort to systematically identify genes, their mutations, and their variants associated with phenotypic variability and indications of human disease or phenotype. Since nutrigenomic research uses genetic information in the design and analysis of experiments, the HVP is an essential collaborator for ongoing studies of gene–nutrient interactions. With the advent of next generation sequencing methodologies and the understanding of the undiscovered variation in human genomes, the nutrigenomic community will be generating novel sequence data and results. The guidelines and practices of the HVP can guide and harmonize these efforts. 相似文献
992.
Mohamed Ben Sghaier Jihed Boubaker Aicha Neffati Ilef Limem Ines Skandrani Wissem Bhouri Ines Bouhlel Soumaya Kilani Leila Chekir‐Ghedira Kamel Ghedira 《化学与生物多样性》2010,7(7):1754-1763
The mutagenic and antimutagenic effects of the essential oil extracted from the aerial parts of Teucrium ramosissimum were evaluated by the bacterial reverse mutation assay in Salmonella typhimurium TA98, TA100, and TA1535, with and without exogenous metabolic activation (S9 fraction). The T. ramosissimum essential oil showed no mutagenic effect. In contrast, our results established that it possessed antimutagenic effects against sodium azide (SA), aflatoxin B1 (AFB1), benzo[a]pyrene (B[a]P), and 4‐nitro‐o‐phenylenediamine (NOPD). The antioxidant capacity of the tested essential oil was evaluated using enzymatic, i.e., the xanthine/xanthine oxidase (X/XOD) assay, and nonenzymatic systems, i.e., the nitro‐blue tetrazolium (NBT)/riboflavin and the DPPH assays. A moderate free radical‐scavenging activity was observed towards DPPH. and O$\rm{{_{2}^{{^\cdot} -}}}$ . In contrast, T. ramosissimum essential oil showed no effect for all the tested concentrations in the X/XOD assay. 相似文献
993.
? Premise of the study: Parthenocissus is a genus of the grape family Vitaceae and has a disjunct distribution in Asia and North America with members in both tropical and temperate regions. The monophyly of Parthenocissus has not yet been tested, and the species relationships and the evolution of its intercontinental disjunction have not been investigated with extensive sampling and molecular phylogenetic methods. ? Methods: Plastid (trnL-F, rps16, and atpB-rbcL) and nuclear GAI1 sequences of 56 accessions representing all 12 Parthenocissus species were analyzed with parsimony, likelihood, and Bayesian inference. Divergence times of disjunct lineages were estimated with relaxed Bayesian dating. Evolution of the leaflet number was assessed by tracing this character onto Bayesian trees using the Trace Character Over Trees option in the program Mesquite. ? Key results: Parthenocissus is monophyletic and sister to the newly described segregate genus Yua. Two major clades within Parthenocissus are recognizable corresponding to their distribution in Asia and North America. The disjunction between the two continents is estimated to be at 21.64 (95% higher posterior densities 10.23-34.89) million years ago. ? Conclusions: Parthenocissus is likely to have derived from the Eocene boreotropical element. Its current Asian-North American disjunction is dated to the early Miocene, congruent with fossil and paleoclimatic evidence. The tropical species is nested within the temperate clade and is inferred to have dispersed from the adjacent temperate regions. Parthenocissus and Yua are best treated as distinct genera. Leaflet number in this genus has a complex history and cannot be used as a character for infrageneric classification. 相似文献
994.
Yanrui Wu Yina Cun Jing Dong Jingru Shao Shengjun Luo Shengjie Nie Haijing Yu Bingrong Zheng Qi Wang Chunjie Xiao 《遗传学报》2010,37(6):371-379
Based on the theory of constitution of Traditional Chinese Medicine (TCM), the human population is divided into nine constitutions including one balanced constitution (Normality) and eight unbalanced constitutions (Yang-deficiency, Yin-deficiency, Phlegm-wetness, Qi-deficiency, Wetness-heat, Blood stasis, Depressed constitution, and Inherited special constitution). Different constitutions have specific metabolic features and different susceptibility to certain diseases. However, whether a genetic basis accounts for such constitution classification is yet to be determined. Here we performed a genetic study to assess the association between genetic variations of metabolic genes including PPARD, PPARG and APM1 and the constitutions. A total of 233 individuals of the Han population in China were classified into four groups, Normality, Yang-deficiency, Yin-deficiency and Phlegm-wetness with whom 23 single nucleotide polymorphisms (SNPs) in the three genes were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Biased distribution of PPARD rs2267669 and rs2076167, APM1 rs7627128 and rs1063539 in Yang-deficiency, PPARG Pro12Ala in Yin-deficiency and PPARD rs2076167, APM1 rs266729 and rs7627128 in Phlegm-wetness were observed. The frequencies of Haplotype13 (Hap13) of PPARG in Yin-deficiency, Hap25 of APM1 in Yang-deficiency and Hap2 of PPARD and Hap14 of PPARG in Phlegm-wetness, were significantly different from those in Normality, suggesting those might be group-associated haplotypes. These results suggested that single SNP and haplotypes of PPARD, PPARG and APM1 may underlie the genetic basis of the constitutions classified in TCM. 相似文献
995.
Ming Nie Qiang Yang Li-Fen Jiang Chang-Ming Fang Jia-Kuan Chen Bo Li 《Biology letters》2010,6(6):811-814
Biomass allocation is an important plant trait that responds plastically to environmental heterogeneities. However, the effects on this trait of pollutants owing to human activities remain largely unknown. In this study, we investigated the response of biomass allocation of Phragmites australis to petroleum pollution by a 13CO2 pulse-labelling technique. Our data show that plant biomass significantly decreased under petroleum pollution, but the root–shoot ratio for both plant biomass and 13C increased with increasing petroleum concentration, suggesting that plants could increase biomass allocation to roots in petroleum-polluted soil. Furthermore, assimilated 13C was found to be significantly higher in soil, microbial biomass and soil respiration after soils were polluted by petroleum. These results suggested that the carbon released from roots is rapidly turned over by soil microbes under petroleum pollution. This study found that plants can modulate biomass allocation in response to petroleum pollution. 相似文献
996.
Awatef Béjaoui Khiari Ibtissem Guériri Radhia Ben Mohammed Boutheina Ben Abdelmoumen Mardassi 《BMC microbiology》2010,10(1):6
Background
In Mycoplasma synoviae, type strain WVU 1853, a single member of the haemaglutinin vlhA gene family has been previously shown to be expressed. Variants of vlhA are expressed from the same unique vlhA promoter by recruiting pseudogene sequences via site-specific recombination events, thus generating antigenic variability. Using a bacterial stock of M. synoviae WVU 1853 that had been colony purified thrice and maintained in our laboratory at low passage level, we previously identified a vlhA gene-related partial coding sequence, referred to as MS2/28.1. The E. coli-expressed product of this partial coding sequence was found to be immunodominant, suggesting that it might be expressed. 相似文献997.
Background
Most of environmental mycobacteria have been previously demonstrated to resist free-living amoeba with subsequent increased virulence and resistance to antibiotics and biocides. The Mycobacterium avium complex (MAC) comprises of environmental organisms that inhabit a wide variety of ecological niches and exhibit a significant degree of genetic variability. We herein studied the intra-ameobal location of all members of the MAC as model organisms for environmental mycobacteria. 相似文献998.
Dolowschiak T Chassin C Ben Mkaddem S Fuchs TM Weiss S Vandewalle A Hornef MW 《PLoS pathogens》2010,6(11):e1001194
The epithelium efficiently attracts immune cells upon infection despite the low number of pathogenic microbes and moderate levels of secreted chemokines per cell. Here we examined whether horizontal intercellular communication between cells may contribute to a coordinated response of the epithelium. Listeria monocytogenes infection, transfection, and microinjection of individual cells within a polarized intestinal epithelial cell layer were performed and activation was determined at the single cell level by fluorescence microscopy and flow cytometry. Surprisingly, chemokine production after L. monocytogenes infection was primarily observed in non-infected epithelial cells despite invasion-dependent cell activation. Whereas horizontal communication was independent of gap junction formation, cytokine secretion, ion fluxes, or nitric oxide synthesis, NADPH oxidase (Nox) 4-dependent oxygen radical formation was required and sufficient to induce indirect epithelial cell activation. This is the first report to describe epithelial cell-cell communication in response to innate immune activation. Epithelial communication facilitates a coordinated infectious host defence at the very early stage of microbial infection. 相似文献
999.
Phleger CF Nelson MM Mooney BD Nichols PD 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2002,131(4):733-747
Antarctic euphausiids, Euphausia superba, E. tricantha, E. frigida and Thysanoessa macrura were collected near Elephant Island ¦ during 1997 and 1998. Total lipid was highest in E. superba small juveniles (16 mg g−1 wet mass), ranging from 12 to 15 mg in other euphausiids. Polar lipid (56–81% of total lipid) and triacylglycerol (12–38%) were the major lipids with wax esters (6%) only present in E. tricantha. Cholesterol was the major sterol (80–100% of total sterols) with desmosterol second in abundance (1–18%). 1997 T. macrura and E. superba contained a more diverse sterol profile, including 24-nordehydrocholesterol (0.1–1.7%), trans-dehydrocholesterol (1.1–1.5%), brassicasterol (0.5–1.7%), 24-methylenecholesterol (0.1–0.4%) and two stanols (0.1–0.2%). Monounsaturated fatty acids included primarily 18:1(n−9)c (7–21%), 18:1(n−7)c (3–13%) and 16:1(n−7)c (2–7%). The main saturated fatty acids in krill were 16:0 (18–29%), 14:0 (2–15%) and 18:0 (1–13%). Highest eicosapentaenoic acid [EPA, 20:5(n−3)] and docosahexaenoic acid [DHA, 22:6(n−3)] occurred in E. superba (EPA, 15–21%; DHA, 9–14%), and were less abundant in other krill. E. superba is a good source of EPA and DHA for consideration of direct or indirect use as a food item for human consumption. Lower levels of 18:4(n−3) in E. tricantha, E. frigida and T. macrura (0.4–0.7% of total fatty acids) are more consistent with a carnivorous or omnivorous diet as compared with herbivorous E. superba (3.7–9.4%). The polyunsaturated fatty acid (PUFA) 18:5(n−3) and the very-long chain (VLC-PUFA), C26 and C28 PUFA, were not present in 1997 samples, but were detected at low levels in most 1998 euphausiids. Interannual differences in these biomarkers suggest greater importance of dinoflagellates or some other phytoplankton group in the Elephant Island area during 1998. The data have enabled between year comparisons of trophodynamic interactions of krill collected in the Elephant Island region, and will be of use to groups using signature lipid methodology. 相似文献
1000.
Kaiwu He Lulin Nie Tahir Ali Shujin Wang Xiao Chen Zizhen Liu Weifen Li Kaiqin Zhang Jia Xu Jianjun Liu ZhiJian Yu Xifei Yang Shupeng Li 《Aging cell》2021,20(12)
Adiponectin (APN) deficiency has also been associated with Alzheimer‐like pathologies. Recent studies have illuminated the importance of APN signaling in reducing Aβ accumulation, and the Aβ elimination mechanism remains rudimentary. Therefore, we aimed to elucidate the APN role in reducing Aβ accumulation and its associated abnormalities by targeting autophagy and lysosomal protein changes. To assess, we performed a combined pharmacological and genetic approach while using preclinical models and human samples. Our results demonstrated that the APN level significantly diminished in the plasma of patients with dementia and 5xFAD mice (6 months old), which positively correlated with Mini‐Mental State Examination (MMSE), and negatively correlated with Clinical Dementia Rating (CDR), respectively. APN deficiency accelerated cognitive impairment, Aβ deposition, and neuroinflammation in 5xFAD mice (5xFAD*APN KO), which was significantly rescued by AdipoRon (AR) treatment. Furthermore, AR treatment also markedly reduced Aβ deposition and attenuated neuroinflammation in APP/PS1 mice without altering APP expression and processing. Interestingly, AR treatment triggered autophagy by mediating AMPK‐mTOR pathway signaling. Most importantly, APN deficiency dysregulated lysosomal enzymes level, which was recovered by AR administration. We further validated these changes by proteomic analysis. These findings reveal that APN is the negative regulator of Aβ deposition and its associated pathophysiologies. To eliminate Aβ both extra‐ and intracellular deposition, APN contributes via the autophagic/lysosomal pathway. It presents a therapeutic avenue for AD therapy by targeting autophagic and lysosomal signaling. 相似文献