952 resultados para Gene Copy Number
Resumo:
Epidemiological studies suggest that low-birth weight infants show poor neonatal growth and increased susceptibility to metabolic syndrome, in particular, obesity and diabetes. Adipose tissue development is regulated by many genes, including members of the peroxisome proliferator-activated receptor (PPAR) and the fatty acid-binding protein (FABP) families. The aim of this study was to determine the influence of birth weight on key adipose and skeletal muscle tissue regulating genes. Piglets from 11 litters were ranked according to birth weight and 3 from each litter assigned to small, normal, or large-birth weight groups. Tissue samples were collected on day 7 or 14. Plasma metabolite concentrations and the expression of PPARG2, PPARA, FABP3, and FABP4 genes were determined in subcutaneous adipose tissue and skeletal muscle. Adipocyte number and area were determined histologically. Expression of FABP3 and 4 was significantly reduced in small and large, compared with normal, piglets in adipose tissue on day 7 and in skeletal muscle on day 14. On day 7, PPARA and PPARG2 were significantly reduced in adipose tissue from small and large piglets. Adipose tissue from small piglets contained more adipocytes than normal or large piglets. Birth weight had no effect on adipose tissue and skeletal muscle lipid content. Low-birth weight is associated with tissue-specific and time-dependent effects on lipid-regulating genes as well as morphological changes in adipose tissue. It remains to be seen whether these developmental changes alter an individual's susceptibility to metabolic syndrome.
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Although there have been a number of studies of effects of diet and hormones on lipoprotein lipase (EC 3.1.1.34; LPL) activity and levels of LPL mRNA (Raynolds et al. 1990), there have been no studies which have investigated effects of different dietary fatty acids on LPL gene expression. In the present study male Wistar Albino rats were pair-fed diets containing 50 g fat/kg of different fatty acid composition for 2 weeks. The diets fed were (1) a mixed oil (450 g saturated fatty acids, 420 g monounsaturated fatty acids, 130 g polyunsaturated fatty acids/kg; n 8), (2) maize oil (n 8), or (3) fish oil (n 8). Animals were killed, RNA was extracted from liver and perirenal and epididymal fat pads, and analysed by ‘Northern methodology’. Samples were hybridized to a human cDNA probe for LPL (Gotoda et al. 1989). Two transcripts were identified in epididymai and perirenal adipose tissue which were approximately 3·7 and 1·7 kb in size. The results suggested that (1) fish oil-fed animals had significantly greater production of LPL mRNA in epididymai adipose tissue compared with maize oil-fed animals (P < 0·05), (2) maize oil-fed animals had significantly greater production of LPL mRNA in perirenal fat compared with the other dietary groups (P < 0·05), (3) expression in the liver was not significant. Rats fed on a fish oil diet had significantly reduced plasma triacylglycerol concentrations compared with the mixed-oil group (P < 0·05), but there were no significant differences in plasma cholesterol. The differences in LPL could not be explained directly by the changes in plasma immunoreactive-insulin and glucose-dependent insulinotrophic polypeptide levels in the three groups.
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Background and aims CCAAT/enhancer-binding protein alpha (CEBPA) is a transcription factor involved in adipogenesis and energy homeostasis. Caloric restriction reduces CEBPA protein expression in patients with metabolic syndrome (MetS). A previous report linked rs12691 SNP in CEBPA to altered concentration of fasting triglycerides. Our objective was to assess the effects of rs12691 in glucose metabolism in Metabolic Syndrome (MetS) patients. Methods and results Glucose metabolism was assessed by static (glucose, insulin, adiponectin, leptin and resistin plasma concentrations) and dynamic (disposition index, insulin sensitivity index, HOMA-IR and acute insulin response to glucose) indices, performed at baseline and after 12 weeks of 4 dietary interventions (high saturated fatty acid (SFA), high monounsaturated fatty acid (MUFA), low-fat and low-fat-high-n3 polyunsaturated fatty acid (PUFA)) in 486 subjects with MetS. Carriers of the minor A allele of rs12691 had altered disposition index (p = 0.0003), lower acute insulin response (p = 0.005) and a lower insulin sensitivity index (p = 0.025) indicating a lower insulin sensitivity and a lower insulin secretion, at baseline and at the end of the diets. Furthermore, A allele carriers displayed lower HDL concentration. Conclusion The presence of the A allele of rs12691 influences glucose metabolism of MetS patients. Clinical Trials Registry number NCT00429195.
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We report here the construction and characterisation of a BAC library from the maize flint inbred line F2, widely used in European maize breeding programs. The library contains 86,858 clones with an average insert size of approximately 90 kb, giving approximately 3.2-times genome coverage. High-efficiency BAC cloning was achieved through the use of a single size selection for the high-molecular-weight genomic DNA, and co-transformation of the ligation with yeast tRNA to optimise transformation efficiency. Characterisation of the library showed that less than 0.5% of the clones contained no inserts, while 5.52% of clones consisted of chloroplast DNA. The library was gridded onto 29 nylon filters in a double-spotted 8 × 8 array, and screened by hybridisation with a number of single-copy and gene-family probes. A 3-dimensional DNA pooling scheme was used to allow rapid PCR screening of the library based on primer pairs from simple sequence repeat (SSR) and expressed sequence tag (EST) markers. Positive clones were obtained in all hybridisation and PCR screens carried out so far. Six BAC clones, which hybridised to a portion of the cloned Rp1-D rust resistance gene, were further characterised and found to form contigs covering most of this complex resistance locus.
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Anticoagulants rodenticides have already known for over half a century, as effective and safe method of rodent control. However, discovered in 1958 anticoagulant resistance has given us a very important problem for their future long-term use. Laboratory tests provide the main method for identification the different types of anticoagulant resistances, quantify the magnitude of their effect and help us to choose the best pest control strategy. The main important tests are lethal feeding period (LFP) and blood clotting response (BCR) tests. These tests can now be used to quantify the likely effect of the resistance on treatment outcome by providing an estimate of the ‘resistance factor’. In 2004 the gene responsible for anticoagulant resistance (VKORC1) was identified and sequenced. As a result, a new molecular resistance testing methodology has been developed, and a number of resistance mutations, particularly in Norway rats and house mice. Three mutations of the VKORC1 gene in Norway rats have been identified to date that confer a degree of resistance to bromadiolone and difenacoum, sufficient to affect treatment outcome in the field.
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Genetic modification of shoot and root morphology has potential to improve water and nutrient 19 uptake of wheat crops in rainfed environments. Near-isogenic lines (NILs) varying for a tillering 20 inhibition (tin) gene and representing multiple genetic backgrounds were investigated in contrasting 21 controlled environments for shoot and root growth. Leaf area, shoot and root biomass were similar 22 until tillering whereupon reduced tillering in tin-containing NILs produced reductions of up to 60% in 23 total leaf area and biomass, and increases in total root length of up to 120% and root biomass to 24 145%. Together, root-to-shoot ratio increased two-fold with the tin gene. The influence of tin on shoot 25 and root growth was greatest in the cv. Banks genetic background, particularly in the biculm-selected 26 NIL, and was typically strongest in cooler environments. A separate de-tillering study confirmed 27 greater root-to-shoot ratios with regular tiller removal in non-tin containing genotypes. In validating 28 these observations in a rainfed field study, the tin allele had a negligible effect on seedling growth but 29 was associated with significantly (P<0.05) reduced tiller number (-37%), leaf area index (-26%) and 30 spike number (-35%) to reduce plant biomass (-19%) at anthesis. Root biomass, root-to-shoot ratio at 31 early stem elongation and root depth at maturity were increased in tin-containing NILs. Soil water use 32 was slowed in tin-containing NILs resulting in greater water availability, greater stomatal 33 conductance, cooler canopy temperatures and maintenance of green leaf area during grain-filling. 34 Together these effects contributed to increases in harvest index and grain yield. In both the controlled 35 and field environments, the tin gene was commonly associated with increased root length and biomass 36 but the significant influence of genetic background and environment suggests careful assessment of 37 tin-containing progeny in selection for genotypic increases in root growth.
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Changes in land management practices may have significant implications for soil microbial communities important in organic P turnover. Soil bacteria can increase plant P availability by excreting phosphatase enzymes which catalyze the hydrolysis of ester-phosphate bonds. Examining the diversity and abundance of alkaline phosphatase gene harboring bacteria may provide valuable insight into alkaline phosphatase production in soils. This study examined the effect of 20 years of no input organic (ORG), organic with composted manure (ORG + M), conventional (CONV) and restored prairie (PRA) management on soil P bioavailability, alkaline phosphatase activity (ALP), and abundance and diversity of ALP gene (phoD) harboring bacteria in soils from the northern Great Plains of Canada. Management system influenced bioavailable P (P < 0.001), but not total P, with the lowest concentrations in the ORG systems and the highest in PRA. Higher rates of ALP were observed in the ORG and ORG + M treatments with a significant negative correlation between bioavailable P and ALP in 2011 (r2 = 0.71; P = 0.03) and 2012 (r2 = 0.51; P = 0.02), suggesting that ALP activity increased under P limiting conditions. The phoD gene abundance was also highest in ORG and ORG + M resulting in a significant positive relationship between bacterial phoD abundance and ALP activity (r2 = 0.71; P = 0.009). Analysis of phoD bacterial community fingerprints showed a higher number of species in CONV compared to ORG and ORG + M, contrary to what was expected considering greater ALP activity under ORG management. In 2012, banding profiles of ORG + M showed fewer phoD bacterial species following the second manure application, although ALP activity is higher than in 2011. This indicates that a few species may be producing more ALP and that quantitative gene analysis was a better indicator of activity than the number of species present.
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This work examined how the conceptus modulates endometrial tissue remodeling and vascular development prior to implantation in mares. A macroscopic uterine examination was completed at day 21 of pregnancy. In situ morphology revealed that the endometrium involved in encroachment is restricted to the dorsal endometrium immediately overlying the yolk sac. The amount of stromal area occupied by blood vessels and the number of endometrial glands were increased during early pregnancy. Endometrial histomorphometry as well as the endometrial mRNA abundance and immunolocalization of VEGF, VEGFR1, VEGFR2, and Ki-67 was completed at days 14 and 21 of pregnancy, at day 10 of the estrous cycle, and during estrus. No obvious differences in VEGF and VEGFR1 protein localization were detected between pregnant and cycling mares but differential staining pattern for VEGFR2 and Ki-67 was observed. VEGFR2 localized to luminal and glandular epithelium of pregnant mares, while luminal epithelium was negative in cycling mares. Ki-67 staining was weak during the luteal phase but exhibited prominent luminal epithelium staining during estrus. In pregnant mares, all endometrial layers were Ki-67 positive. Quantitative RT-PCR revealed a greater abundance of VEGF mRNA during pregnancy. VEGFR2 transcript abundance was greatest in pregnant mares on day 21. This study supports the concept that the conceptus plays an active role in directing vasculogenesis within the uterus and thereby establishing hemotrophic nutrition that supports pregnancy after implantation. Reproduction (2011) 142 593-603
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Diabetic patients have increased susceptibility to infection, which may be related to impaired inflammatory response observed in experimental models of diabetes, and restored by insulin treatment. The goal of this study was to investigate whether insulin regulates transcription of cytokines and intercellular adhesion molecule 1 (ICAM-1) via nuclear factor-kappa B (NF-kappa B) signaling pathway in Escherichia coli LIPS-induced lung inflammation. Diabetic male Wistar rats (alloxan, 42 mg/kg, iv., 10 days) and controls were instilled intratracheally with saline containing LPS (750 mu g/0.4 mL) or saline only. Some diabetic rats were given neutral protamine Hagedorn insulin (4 IU, s.c.) 2 h before LIPS. Analyses performed 6 h after LPS included: (a) lung and mesenteric lymph node IL-1 beta, TNF-alpha, IL-10, and ICAM-1 messenger RNA (mRNA) were quantified by real-time reverse transcriptase-polymerase chain reaction; (b) number of neutrophils in the bronchoalveolar lavage (BAL) fluid, and concentrations of IL-1 beta, TNF-alpha, and IL-10 in the BAL were determined by the enzyme-linked immunosorbent assay; and (c) activation of NF-kappa B p65 subunit and phosphorylation of I-kappa B alpha were quantified by Western blot analysis. Relative to controls, diabetic rats exhibited a reduction in lung and mesenteric lymph node IL-1 beta (40%), TNF-alpha (similar to 30%), and IL-10 (similar to 40%) mRNA levels and reduced concentrations of IL-1 beta (52%), TNF-alpha (62%), IL-10 (43%), and neutrophil counts (72%) in the BAL. Activation of NF-kappa B p65 subunit and phosphorylation of I-kappa B alpha were almost suppressed in diabetic rats. Treatment of diabetic rats with insulin completely restored mRNA and protein levels of these cytokines and potentiated lung ICAM-1 mRNA levels (30%) and number of neutrophils (72%) in the BAL. Activation of NF-kappa B p65 subunit and phosphorylation of I-kappa B alpha were partially restored by insulin treatment. In conclusion, data presented suggest that insulin regulates transcription of proinflammatory (IL-1 beta, TNF-alpha) and anti-inflammatory (IL-10) cytokines, and expression of ICAM-1 via the NF-kappa B signaling pathway.
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The numbers of culturable diazotrophic endophytic bacteria (CDEB) from roots stems and leaves of sugarcane submitted to organic inorganic or no fertilization were compared In order to determine the size of the N(2) fixing populations the Most Probable Number technique (MPN) was used The quantification of diazotrophic bacteria by using the acetylene reduction assay (ARA) was more accurate than observing the bacterial growth in the vials to confirm N(2) fixing capability the detection of gene nifH was performed on a sample of 105 Isolated bacteria The production of extracellular enzymes involved in the penetration of the plants by the bacteria was also studied The results showed that organic fertilization enhances the number of CDEB when compared with conventional fertilization used throughout the growing season The maximum number of bacteria was detected in the roots Roots and stems presented the greatest number of CDEB in the middle of the cropping season and in leaves numbers varied according to the treatment Using two pairs of primers and two different methods the nifH gene was found in 104 of the 105 tested isolates Larger amounts of pectinase were released by isolates from sugarcane treated with conventional fertilizers (66%) whereas larger amounts of cellulase were released by strains isolated from sugarcane treated with organic fertilizers (80%) (C) 2010 Elsevier Masson SAS All rights reserved
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The biosynthesis of quinolinate, the de novo precursor of nicotinamide adenine dinucleotide (NAD), may be performed by two distinct pathways, namely, the bacterial aspartate (aspartate-to-quinolinate) and the eukaryotic kynurenine (tryptophan-to-quinolinate). Even though the separation into eukaryotic and bacterial routes is long established, recent genomic surveys have challenged this view, because certain bacterial species also carry the genes for the kynurenine pathway. In this work, both quinolinate biosynthetic pathways were investigated in the Bacteria clade and with special attention to Xanthomonadales and Bacteroidetes, from an evolutionary viewpoint. Genomic screening has revealed that a small number of bacterial species possess some of the genes for the kynurenine pathway, which is complete in the genus Xanthomonas and in the order Flavobacteriales, where the aspartate pathway is absent. The opposite pattern (presence of the aspartate pathway and absence of the kynurenine pathway) in close relatives (Xylella ssp. and the order Bacteroidales, respectively) points to the idea of a recent acquisition of the kynurenine pathway through lateral gene transfer in these bacterial groups. In fact, sequence similarity comparison and phylogenetic reconstruction both suggest that at least part of the genes of the kynurenine pathway in Xanthomonas and Flavobacteriales is shared by eukaryotes. These results reinforce the idea of the role that lateral gene transfer plays in the configuration of bacterial genomes, thereby providing alternative metabolic pathways, even with the replacement of primary and essential cell functions, as exemplified by NAD biosynthesis.
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The human malaria parasite Plasmodium falciparum expresses erythrocyte-surface directed variant antigens which are important virulence factors Many are transcribed from multigene families and presumably their mode of expression is strictly controlled to guarantee immune evasion in the human host. In order to elucidate the dynamics of rif transcription and to investigate if rif switching is comparable to var switching we monitored rif variant gene expression in parasites with different cytoadhesive properties as well as after a number of reinvasions. We found identical transcripts in parasite lines with different adhesive phenotypes suggesting that rif genes do not have a critical role in determining the cytoadhesion specificity of infected erythrocytes. We show for the first time that rif genes may show a conserved mode of transcription, maintaining the previously dominant rif transcript in subsequent reinvasions, but also observed rapid switching at rates up to 45% per generation, much higher than for the var gene family. (C) 2009 Elsevier B.V. All rights reserved.
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Mycoplasma synoviae (MS) is an important avian pathogen may cause both respiratory disease and joint inflammation synovitis in poultry, causing economic losses to the Brazilian poultry industry. The genotypic variation in 16S rRNA gene is unknown. Partial sequences of 16S rRNA gene of 19 strains of M. synoviae were sequenced and analyzed in order to obtain molecular characterization and evaluation of the genetic variability of strains from distinct Brazilian areas of poultry production. Different polymorphic patterns were observed. The number of polymorphic alterations in the studied strains ranged from 0 to 6. The nucleotide variations, including deletion, insertion and substitutions, ranged from 3 to 5. The genotypic diversity observed in this study may be explained by spontaneous mutations that may occur when a lineage remains in the same flock for long periods. The culling and reposition in poultry flocks may be responsible for the entry of new strains in different areas. (C) 2008 Elsevier Ltd. All rights reserved.
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Autosomal recessive spastic paraplegia with thinning of corpus callosum (ARHSP-TCC) is a complex form of HSP initially described in Japan but subsequently reported to have a worldwide distribution with a particular high frequency in multiple families from the Mediterranean basin. We recently showed that ARHSP-TCC is commonly associated with mutations in SPG11/KIAA1840 on chromosome 15q. We have now screened a collection of new patients mainly originating from Italy and Brazil, in order to further ascertain the spectrum of mutations in SPG11, enlarge the ethnic origin of SPG11 patients, determine the relative frequency at the level of single Countries (i.e., Italy), and establish whether there is one or more common mutation. In 25 index cases we identified 32 mutations; 22 are novel, including 9 nonsense, 3 small deletions, 4 insertions, 1 in/del, 1 small duplication, 1 missense, 2 splice-site, and for the first time a large genomic rearrangement. This brings the total number of SPG11 mutated patients in the SPATAX collection to 111 cases in 44 families and in 17 isolated cases, from 16 Countries, all assessed using homogeneous clinical criteria. While expanding the spectrum of mutations in SPG11, this larger series also corroborated the notion that even within apparently homogeneous population a molecular diagnosis cannot be achieved without full gene sequencing. (C) 2008 Wiley-Liss, Inc.
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Denote by R(L, L, L) the minimum integer N such that any 3-coloring of the edges of the complete graph on N vertices contains a monochromatic copy of a graph L. Bondy and Erdos conjectured that when L is the cycle C(n) on n vertices, R(C(n), C(n), C(n)) = 4n - 3 for every odd n > 3. Luczak proved that if n is odd, then R(C(n), C(n), C(n)) = 4n + o(n), as n -> infinity, and Kohayakawa, Simonovits and Skokan confirmed the Bondy-Erdos conjecture for all sufficiently large values of n. Figaj and Luczak determined an asymptotic result for the `complementary` case where the cycles are even: they showed that for even n, we have R(C(n), C(n), C(n)) = 2n + o(n), as n -> infinity. In this paper, we prove that there exists n I such that for every even n >= n(1), R(C(n), C(n), C(n)) = 2n. (C) 2009 Elsevier Inc. All rights reserved.