995 research outputs found
Avaliação de hĂbridos comerciais de milho em ĂĄreas de arroz irrigado no Rio Grande do Sul. 2000/01 e 2001/02.
bitstream/item/31547/1/comunicado62.pd
A precision study of the fine tuning in the DiracNMSSM
Recently the DiracNMSSM has been proposed as a possible solution to reduce
the fine tuning in supersymmetry. We determine the degree of fine tuning needed
in the DiracNMSSM with and without non-universal gaugino masses and compare it
with the fine tuning in the GNMSSM. To apply reasonable cuts on the allowed
parameter regions we perform a precise calculation of the Higgs mass. In
addition, we include the limits from direct SUSY searches and dark matter
abundance. We find that both models are comparable in terms of fine tuning,
with the minimal fine tuning in the GNMSSM slightly smaller.Comment: 20 pages + appendices, 10 figure
Sialic Acid Glycobiology Unveils Trypanosoma cruzi Trypomastigote Membrane Physiology.
Trypanosoma cruzi, the flagellate protozoan agent of Chagas disease or American trypanosomiasis, is unable to synthesize sialic acids de novo. Mucins and trans-sialidase (TS) are substrate and enzyme, respectively, of the glycobiological system that scavenges sialic acid from the host in a crucial interplay for T. cruzi life cycle. The acquisition of the sialyl residue allows the parasite to avoid lysis by serum factors and to interact with the host cell. A major drawback to studying the sialylation kinetics and turnover of the trypomastigote glycoconjugates is the difficulty to identify and follow the recently acquired sialyl residues. To tackle this issue, we followed an unnatural sugar approach as bioorthogonal chemical reporters, where the use of azidosialyl residues allowed identifying the acquired sugar. Advanced microscopy techniques, together with biochemical methods, were used to study the trypomastigote membrane from its glycobiological perspective. Main sialyl acceptors were identified as mucins by biochemical procedures and protein markers. Together with determining their shedding and turnover rates, we also report that several membrane proteins, including TS and its substrates, both glycosylphosphatidylinositol-anchored proteins, are separately distributed on parasite surface and contained in different and highly stable membrane microdomains. Notably, labeling for α(1,3)Galactosyl residues only partially colocalize with sialylated mucins, indicating that two species of glycosylated mucins do exist, which are segregated at the parasite surface. Moreover, sialylated mucins were included in lipid-raft-domains, whereas TS molecules are not. The location of the surface-anchored TS resulted too far off as to be capable to sialylate mucins, a role played by the shed TS instead. Phosphatidylinositol-phospholipase-C activity is actually not present in trypomastigotes. Therefore, shedding of TS occurs via microvesicles instead of as a fully soluble form
Nutritional value of the larvae of the black soldier fly (Hermetia illucens) and the house fly (Musca domestica) as a food alternative for farm animal: a systematic review.
Dietary alternatives using insect-based products as an alternative for farm animal nutrition have been the object of study due to the high nutritional value of these feeds and the costs related to both their production and consequently their commercialization. Thus, the use of flies, especially larvae, has a high content of proteins and lipids (fat), as well as minerals and essential nutrients for development and growth, directly impacting the production of these animals, whether meat or milk. Therefore, the objective of this study was to compile data from the literature on the nutritional value of adults and larvae of Black soldier (Hermetia illucens) and housefly (Musca domestica) as a dietary alternative for animal feed. The Prisma checklist was used. After reviewing the data found in the literature, following the systematic review, it was noted that studies emerge that larvae of black soldier flies and domestic flies of the order Diptera obtain essential sources in the nutrition of ruminants, in addition to obtaining rapid digestibility, thus adhering to reproduction with high nutritional content, due to incident levels of protein, lipids, and minerals in M. domestica and Lucilia sericata, making it a target for inclusion in the diet of farm animals. In addition, it is concluded that both species are studied for their sustainable potential as well as for offering greater economic and nutritional viability when compared to ingredients present in production animal feed
Simultaneous CXCL12 and ESR1 CpG island hypermethylation correlates with poor prognosis in sporadic breast cancer
<p>Abstract</p> <p>Background</p> <p>CXCL12 is a chemokine that is constitutively expressed in many organs and tissues. <it>CXCL12 </it>promoter hypermethylation has been detected in primary breast tumours and contributes to their metastatic potential. It has been shown that the oestrogen receptor α (<it>ESR1</it>) gene can also be silenced by DNA methylation. In this study, we used methylation-specific PCR (MSP) to analyse the methylation status in two regions of the <it>CXCL12 </it>promoter and <it>ESR1 </it>in tumour cell lines and in primary breast tumour samples, and correlated our results with clinicopathological data.</p> <p>Methods</p> <p>First, we analysed <it>CXCL12 </it>expression in breast tumour cell lines by RT-PCR. We also used 5-aza-2'-deoxycytidine (5-aza-CdR) treatment and DNA bisulphite sequencing to study the promoter methylation for a specific region of <it>CXCL12 </it>in breast tumour cell lines. We evaluated <it>CXCL12 </it>and <it>ESR1 </it>methylation in primary tumour samples by methylation-specific PCR (MSP). Finally, promoter hypermethylation of these genes was analysed using Fisher's exact test and correlated with clinicopathological data using the Chi square test, Kaplan-Meier survival analysis and Cox regression analysis.</p> <p>Results</p> <p><it>CXCL12 </it>promoter hypermethylation in the first region (island 2) and second region (island 4) was correlated with lack of expression of the gene in tumour cell lines. In the primary tumours, island 2 was hypermethylated in 14.5% of the samples and island 4 was hypermethylated in 54% of the samples. The <it>ESR1 </it>promoter was hypermethylated in 41% of breast tumour samples. In addition, the levels of ERα protein expression diminished with increased frequency of <it>ESR1 </it>methylation (p < 0.0001). This study also demonstrated that <it>CXCL12 </it>island 4 and <it>ESR1 </it>methylation occur simultaneously at a high frequency (p = 0.0220).</p> <p>Conclusions</p> <p>This is the first study showing a simultaneous involvement of epigenetic regulation for both <it>CXCL12 </it>and <it>ESR1 </it>genes in Brazilian women. The methylation status of both genes was significantly correlated with histologically advanced disease, the presence of metastases and death. Therefore, the methylation pattern of these genes could be used as a molecular marker for the prediction of breast cancer outcome.</p
Pathogenic mycobacteria achieve cellular persistence by inhibiting the Niemann-Pick Type C disease cellular pathway
Background. Tuberculosis remains a major global health concern. The ability to prevent phagosome-lysosome fusion is a key mechanism by which intracellular mycobacteria, including Mycobacterium tuberculosis, achieve long-term persistence within host cells. The mechanisms underpinning this key intracellular pro-survival strategy remain incompletely understood. Host macrophages infected with intracellular mycobacteria share phenotypic similarities with cells taken from patients suffering from Niemann-Pick Disease Type C (NPC), a rare lysosomal storage disease in which endocytic trafficking defects and lipid accumulation within the lysosome lead to cell dysfunction and cell death. We investigated whether these shared phenotypes reflected an underlying mechanistic connection between mycobacterial intracellular persistence and the host cell pathway dysfunctional in NPC. Methods. The induction of NPC phenotypes in macrophages from wild-type mice or obtained from healthy human donors was assessed via infection with mycobacteria and subsequent measurement of lipid levels and intracellular calcium homeostasis. The effect of NPC therapeutics on intracellular mycobacterial load was also assessed. Results. Macrophages infected with intracellular mycobacteria phenocopied NPC cells, exhibiting accumulation of multiple lipid types, reduced lysosomal Ca 2+ levels, and defects in intracellular trafficking. These NPC phenotypes could also be induced using only lipids/glycomycolates from the mycobacterial cell wall. These data suggest that intracellular mycobacteria inhibit the NPC pathway, likely via inhibition of the NPC1 protein, and subsequently induce altered acidic store Ca 2+ homeostasis. Reduced lysosomal calcium levels may provide a mechanistic explanation for the reduced levels of phagosome-lysosome fusion in mycobacterial infection. Treatments capable of correcting defects in NPC mutant cells via modulation of host cell calcium were of benefit in promoting clearance of mycobacteria from infected host cells. Conclusion. These findings provide a novel mechanistic explanation for mycobacterial intracellular persistence, and suggest that targeting interactions between the mycobacteria and host cell pathways may provide a novel avenue for development of anti-TB therapies
Rare disruptive variants in the DISC1 Interactome and Regulome : association with cognitive ability and schizophrenia
Schizophrenia (SCZ), bipolar disorder (BD) and recurrent major depressive disorder (rMDD) are common psychiatric illnesses. All have been associated with lower cognitive ability, and show evidence of genetic overlap and substantial evidence of pleiotropy with cognitive function and neuroticism. Disrupted in schizophrenia 1 (DISC1) protein directly interacts with a large set of proteins (DISC1 Interactome) that are involved in brain development and signaling. Modulation of DISC1 expression alters the expression of a circumscribed set of genes (DISC1 Regulome) that are also implicated in brain biology and disorder. Here we report targeted sequencing of 59 DISC1 Interactome genes and 154 Regulome genes in 654 psychiatric patients and 889 cognitively-phenotyped control subjects, on whom we previously reported evidence for trait association from complete sequencing of the DISC1 locus. Burden analyses of rare and singleton variants predicted to be damaging were performed for psychiatric disorders, cognitive variables and personality traits. The DISC1 Interactome and Regulome showed differential association across the phenotypes tested. After family-wise error correction across all traits (FWERacross), an increased burden of singleton disruptive variants in the Regulome was associated with SCZ (FWERacross P=0.0339). The burden of singleton disruptive variants in the DISC1 Interactome was associated with low cognitive ability at age 11 (FWERacross P=0.0043). These results identify altered regulation of schizophrenia candidate genes by DISC1 and its core Interactome as an alternate pathway for schizophrenia risk, consistent with the emerging effects of rare copy number variants associated with intellectual disability.Peer reviewe
Proteome from patients with metabolic syndrome is regulated by quantity and quality of dietary lipids
Background: Metabolic syndrome is a multi-component disorder associated to a high risk of cardiovascular disease.
Its etiology is the result of a complex interaction between genetic and environmental factors, including dietary
habits. We aimed to identify the target proteins modulated by the long-term consumption of four diets differing in
the quality and quantity of lipids in the whole proteome of peripheral blood mononuclear cells (PBMC).
Results: A randomized, controlled trial conducted within the LIPGENE study assigned 24 MetS patients for 12 weeks
each to 1 of 4 diets: a) high-saturated fatty acid (HSFA), b) high-monounsaturated fatty acid (HMUFA), c) low-fat,
high-complex carbohydrate diets supplemented with placebo (LFHCC) and d) low-fat, high-complex carbohydrate
diets supplemented with long chain (LC) n-3 polyunsaturated fatty acids (PUFA) (LFHCC n-3). We analyzed the
changes induced in the proteome of both nuclear and cytoplasmic fractions of PBMC using 2-D proteomic analysis.
Sixty-seven proteins were differentially expressed after the long-term consumption of the four diets. The HSFA diet
induced the expression of proteins responding to oxidative stress, degradation of ubiquitinated proteins and DNA
repair. However, HMUFA, LFHCC and LFHCC n-3 diets down-regulated pro-inflammatory and oxidative stress-related
proteins and DNA repairing proteins.
Conclusion: The long-term consumption of HSFA, compared to HMUFA, LFHCC and LFHCC n-3, seems to increase the
cardiovascular disease (CVD) risk factors associated with metabolic syndrome, such as inflammation and oxidative stress,
and seem lead to DNA damage as a consequence of high oxidative stress
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