220 research outputs found
Immunity toward H1N1 influenza hemagglutinin of historical and contemporary strains suggests protection and vaccine failure
Evolution of H1N1 influenza A outbreaks of the past 100 years is interesting and significantly complex and details of H1N1 genetic drift remains unknown. Here we investigated the clinical characteristics and immune cross-reactivity of significant historical H1N1 strains. We infected ferrets with H1N1 strains from 1943, 1947, 1977, 1986, 1999, and 2009 and showed each produced a unique clinical signature. We found significant cross-reactivity between viruses with similar HA sequences. Interestingly, A/FortMonmouth/1/1947 antisera cross-reacted with A/USSR/90/1977 virus, thought to be a 1947 resurfaced virus. Importantly, our immunological data that didn't show cross-reactivity can be extrapolated to failure of past H1N1 influenza vaccines, ie. 1947, 1986 and 2009. Together, our results help to elucidate H1N1 immuno-genetic alterations that occurred in the past 100 years and immune responses caused by H1N1 evolution. This work will facilitate development of future influenza therapeutics and prophylactics such as influenza vaccines.published_or_final_versio
Transcriptional Activation of REST by Sp1 in Huntington's Disease Models
In Huntington's disease (HD), mutant huntingtin (mHtt) disrupts the normal transcriptional program of disease neurons by altering the function of several gene expression regulators such as Sp1. REST (Repressor Element-1 Silencing Transcription Factor), a key regulator of neuronal differentiation, is also aberrantly activated in HD by a mechanism that remains unclear. Here, we show that the level of REST mRNA is increased in HD mice and in NG108 cells differentiated into neuronal-like cells and expressing a toxic mHtt fragment. Using luciferase reporter gene assay, we delimited the REST promoter regions essential for mHtt-mediated REST upregulation and found that they contain Sp factor binding sites. We provide evidence that Sp1 and Sp3 bind REST promoter and interplay to fine-tune REST transcription. In undifferentiated NG108 cells, Sp1 and Sp3 have antagonistic effect, Sp1 acting as an activator and Sp3 as a repressor. Upon neuronal differentiation, we show that the amount and ratio of Sp1/Sp3 proteins decline, as does REST expression, and that the transcriptional role of Sp3 shifts toward a weak activator. Therefore, our results provide new molecular information to the transcriptional regulation of REST during neuronal differentiation. Importantly, specific knockdown of Sp1 abolishes REST upregulation in NG108 neuronal-like cells expressing mHtt. Our data together with earlier reports suggest that mHtt triggers a pathogenic cascade involving Sp1 activation, which leads to REST upregulation and repression of neuronal genes
Rest-Mediated Regulation of Extracellular Matrix Is Crucial for Neural Development
Neural development from blastocysts is strictly controlled by intricate transcriptional programmes that initiate the down-regulation of pluripotent genes, Oct4, Nanog and Rex1 in blastocysts followed by up-regulation of lineage-specific genes as neural development proceeds. Here, we demonstrate that the expression pattern of the transcription factor Rest mirrors those of pluripotent genes during neural development from embryonic stem (ES) cells and an early abrogation of Rest in ES cells using a combination of gene targeting and RNAi approaches causes defects in this process. Specifically, Rest ablation does not alter ES cell pluripotency, but impedes the production of Nestin+ neural stem cells, neural progenitor cells and neurons, and results in defective adhesion, decrease in cell proliferation, increase in cell death and neuronal phenotypic defects typified by a reduction in migration and neurite elaboration. We also show that these Rest-null phenotypes are due to the dysregulation of its direct or indirect target genes, Lama1, Lamb1, Lamc1 and Lama2 and that these aberrant phenotypes can be rescued by laminins
The Effect of the CO32- to Ca2+ Ion activity ratio on calcite precipitation kinetics and Sr2+ partitioning
<p>Abstract</p> <p>Background</p> <p>A proposed strategy for immobilizing trace metals in the subsurface is to stimulate calcium carbonate precipitation and incorporate contaminants by co-precipitation. Such an approach will require injecting chemical amendments into the subsurface to generate supersaturated conditions that promote mineral precipitation. However, the formation of reactant mixing zones will create gradients in both the saturation state and ion activity ratios (i.e., <inline-formula><m:math name="1467-4866-13-1-i1" xmlns:m="http://www.w3.org/1998/Math/MathML"><m:msub><m:mrow><m:mi>a</m:mi></m:mrow><m:mrow><m:mi>C</m:mi><m:msup><m:mrow><m:msub><m:mrow><m:mi>O</m:mi></m:mrow><m:mrow><m:mn>3</m:mn></m:mrow></m:msub></m:mrow><m:mrow><m:mn>2</m:mn><m:mo class="MathClass-bin">-</m:mo></m:mrow></m:msup></m:mrow></m:msub><m:mo class="MathClass-bin">/</m:mo><m:msub><m:mrow><m:mi>a</m:mi></m:mrow><m:mrow><m:mi>C</m:mi><m:msup><m:mrow><m:mi>a</m:mi></m:mrow><m:mrow><m:mn>2</m:mn><m:mo class="MathClass-bin">+</m:mo></m:mrow></m:msup></m:mrow></m:msub></m:math></inline-formula>). To better understand the effect of ion activity ratios on CaCO<sub>3 </sub>precipitation kinetics and Sr<sup>2+ </sup>co-precipitation, experiments were conducted under constant composition conditions where the supersaturation state (Ω) for calcite was held constant at 9.4, but the ion activity ratio <inline-formula><m:math name="1467-4866-13-1-i2" xmlns:m="http://www.w3.org/1998/Math/MathML"><m:mrow><m:mo class="MathClass-open">(</m:mo><m:mrow><m:mi>r</m:mi><m:mo class="MathClass-rel">=</m:mo><m:msub><m:mrow><m:mi>a</m:mi></m:mrow><m:mrow><m:mi>C</m:mi><m:msup><m:mrow><m:msub><m:mrow><m:mi>O</m:mi></m:mrow><m:mrow><m:mn>3</m:mn></m:mrow></m:msub></m:mrow><m:mrow><m:mn>2</m:mn><m:mo class="MathClass-bin">-</m:mo></m:mrow></m:msup></m:mrow></m:msub><m:mo class="MathClass-bin">/</m:mo><m:msub><m:mrow><m:mi>a</m:mi></m:mrow><m:mrow><m:mi>C</m:mi><m:msup><m:mrow><m:mi>a</m:mi></m:mrow><m:mrow><m:mn>2</m:mn><m:mo class="MathClass-bin">+</m:mo></m:mrow></m:msup></m:mrow></m:msub></m:mrow><m:mo class="MathClass-close">)</m:mo></m:mrow></m:math></inline-formula> was varied between 0.0032 and 4.15.</p> <p>Results</p> <p>Calcite was the only phase observed, by XRD, at the end of the experiments. Precipitation rates increased from 41.3 ± 3.4 μmol m<sup>-2 </sup>min<sup>-1 </sup>at <it>r = </it>0.0315 to a maximum rate of 74.5 ± 4.8 μmol m<sup>-2 </sup>min<sup>-1 </sup>at <it>r = </it>0.306 followed by a decrease to 46.3 ± 9.6 μmol m<sup>-2 </sup>min<sup>-1 </sup>at <it>r </it>= 1.822. The trend was simulated using a simple mass transfer model for solute uptake at the calcite surface. However, precipitation rates at fixed saturation states also evolved with time. Precipitation rates accelerated for low <it>r </it>values but slowed for high <it>r </it>values. These trends may be related to changes in effective reactive surface area. The <inline-formula><m:math xmlns:m="http://www.w3.org/1998/Math/MathML" name="1467-4866-13-1-i1"><m:msub><m:mrow><m:mi>a</m:mi></m:mrow><m:mrow><m:mi>C</m:mi><m:msup><m:mrow><m:msub><m:mrow><m:mi>O</m:mi></m:mrow><m:mrow><m:mn>3</m:mn></m:mrow></m:msub></m:mrow><m:mrow><m:mn>2</m:mn><m:mo class="MathClass-bin">-</m:mo></m:mrow></m:msup></m:mrow></m:msub><m:mo class="MathClass-bin">/</m:mo><m:msub><m:mrow><m:mi>a</m:mi></m:mrow><m:mrow><m:mi>C</m:mi><m:msup><m:mrow><m:mi>a</m:mi></m:mrow><m:mrow><m:mn>2</m:mn><m:mo class="MathClass-bin">+</m:mo></m:mrow></m:msup></m:mrow></m:msub></m:math></inline-formula> ratios did not affect the distribution coefficient for Sr in calcite (D<sup>P</sup><sub>Sr</sub><sup>2+</sup>), apart from the indirect effect associated with the established positive correlation between D<sup>P</sup><sub>Sr</sub><sup>2+ </sup>and calcite precipitation rate.</p> <p>Conclusion</p> <p>At a constant supersaturation state (Ω = 9.4), varying the ion activity ratio affects the calcite precipitation rate. This behavior is not predicted by affinity-based rate models. Furthermore, at the highest ion ratio tested, no precipitation was observed, while at the lowest ion ratio precipitation occurred immediately and valid rate measurements could not be made. The maximum measured precipitation rate was 2-fold greater than the minima, and occurred at a carbonate to calcium ion activity ratio of 0.306. These findings have implications for predicting the progress and cost of remediation operations involving enhanced calcite precipitation where mineral precipitation rates, and the spatial/temporal distribution of those rates, can have significant impacts on the mobility of contaminants.</p
Incidence and Severity of Coronary Artery Disease in Patients with Atrial Fibrillation Undergoing First-Time Coronary Angiography
In standard reference sources, the incidence of coronary artery disease (CAD) in patients with atrial fibrillation (AF) ranged between 24 and 46.5%. Since then, the incidence of cardiovascular risk factors (CRF) has increased and modern treatment strategies ("pill in the pocket") are only applicable to patients without structural heart disease. The aim of this study was to investigate the incidence and severity of CAD in patients with AF.From January 2005 until December 2009, we included 261 consecutive patients admitted to hospital with paroxysmal, persistent or permanent AF in this prospective study. All patients underwent coronary angiography and the Framingham risk score (FRS) was calculated. Patients with previously diagnosed or previously excluded CAD were excluded.The overall incidence of CAD in patients presenting with AF was 34%; in patients >70 years, the incidence of CAD was 41%. The incidence of patients undergoing a percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) was 21%. Patients with CAD were older (73±8 years vs 68±10 years, p = 0.001), had significantly more frequent hypercholesterolemia (60% vs 30%, p<0.001), were more frequent smokers (26% vs 13%, p = 0.017) and suffered from angina more often (37% vs 2%, p<0.001). There was a significant linear trend among the FRS categories in percentage and the prevalence of CAD and PCI/CABG (p<0.0001).The overall incidence of CAD in patients presenting with AF was relatively high at 34%; the incidence of PCI/CABG was 21%. Based upon increasing CRF in the western world, we recommend a careful investigation respecting the FRS to either definitely exclude or establish an early diagnosis of CAD--which could contribute to an early and safe therapeutic strategy considering type Ic antiarrhythmics and oral anticoagulation
Rare Exonic Minisatellite Alleles in MUC2 Influence Susceptibility to Gastric Carcinoma
BACKGROUND: Mucins are the major components of mucus and their genes share a common, centrally-located region of sequence that encodes tandem repeats. Mucins are well known genes with respect to their specific expression levels; however, their genomic levels are unclear because of complex genomic properties. In this study, we identified eight novel minisatellites from the entire MUC2 region and investigated how allelic variation in these minisatellites may affect susceptibility to gastrointestinal cancer. METHODOLOGY/PRINCIPLE FINDINGS: We analyzed genomic DNA from the blood of normal healthy individuals and multi-generational family groups. Six of the eight minisatellites exhibited polymorphism and were transmitted meiotically in seven families, following Mendelian inheritance. Furthermore, a case-control study was performed that compared genomic DNA from 457 cancer-free controls with DNA from individuals with gastric (455), colon (192) and rectal (271) cancers. A statistically significant association was identified between rare exonic MUC2-MS6 alleles and the occurrence of gastric cancer: odds ratio (OR), 2.56; 95% confidence interval (CI), 1.31-5.04; and p = 0.0047. We focused on an association between rare alleles and gastric cancer. Rare alleles were divided into short (40, 43 and 44) and long (47, 50 and 54), according to their TR (tandem repeats) lengths. Interestingly, short rare alleles were associated with gastric cancer (OR = 5.6, 95% CI: 1.93-16.42; p = 0.00036). Moreover, hypervariable MUC2 minisatellites were analyzed in matched blood and cancer tissue from 28 patients with gastric cancer and in 4 cases of MUC2-MS2, minisatellites were found to have undergone rearrangement. CONCLUSIONS/SIGNIFICANCE: Our observations suggest that the short rare MUC2-MS6 alleles could function as identifiers for risk of gastric cancer. Additionally, we suggest that minisatellite instability might be associated with MUC2 function in cancer cells
Distribution of cytogenetic abnormalities in myelodysplastic syndromes, Philadelphia negative myeloproliferative neoplasms, and the overlap MDS/MPN category
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Environmental enrichment reduces signs of boredom in caged mink
Animals housed in impoverished cages are often labelled 'bored'. They have also been called 'apathetic' or 'depressed', particularly when profoundly inactive. However, these terms are rarely operationally defined and validated. As a negative state caused by under-stimulation, boredom should increase interest in stimuli of all kinds. Apathy (lack of interest), by contrast, should manifest as decreased interest in all stimuli, while anhedonia (loss of pleasure, a depressive symptom) should specifically decrease interest in normally rewarding stimuli. We tested the hypotheses that mink, a model carnivore, experience more boredom, depression-like apathy, or anhedonia in non-enriched (NE) cages than in complex, enriched (E) cages. We exposed 29 subjects (13 E, 16 NE) to ten stimuli categorized a priori as aversive (e.g. air puffs), rewarding (e.g. evoking chasing) or ambiguous/neutral (e.g. candles). Interest in stimuli was assessed via latencies to contact, contact durations, and durations oriented to stimuli. NE mink contacted all stimuli faster (P = 0.003) than E mink, and spent longer oriented to/in contact with them, albeit only significantly so for ambiguous ones (treatment*type P<0.013). With stimulus category removed from statistical models, interest in all stimuli was consistently higher among NE mink (P<0.0001 for all measures). NE mink also consumed more food rewards (P = 0.037). Finally, we investigated whether lying down while awake and stereotypic behaviour (both increased by NE housing) predicted these responses. Lying awake positively co-varied with certain measures of increased exploration. In contrast, stereotypic 'scrabbling' or locomotion (e.g. pacing) did not. Overall, NE mink showed no evidence of apathy or depression, but instead a heightened investigation of diverse stimuli consistent with boredom. This state was potentially indicated by spending much time lying still but awake (although this result requires replication). Boredom can thus be operationalized and assessed empirically in non-human animals. It can also be reduced by environmental enrichment
Transcriptional Profiling of Human Liver Identifies Sex-Biased Genes Associated with Polygenic Dyslipidemia and Coronary Artery Disease
Sex-differences in human liver gene expression were characterized on a genome-wide scale using a large liver sample collection, allowing for detection of small expression differences with high statistical power. 1,249 sex-biased genes were identified, 70% showing higher expression in females. Chromosomal bias was apparent, with female-biased genes enriched on chrX and male-biased genes enriched on chrY and chr19, where 11 male-biased zinc-finger KRAB-repressor domain genes are distributed in six clusters. Top biological functions and diseases significantly enriched in sex-biased genes include transcription, chromatin organization and modification, sexual reproduction, lipid metabolism and cardiovascular disease. Notably, sex-biased genes are enriched at loci associated with polygenic dyslipidemia and coronary artery disease in genome-wide association studies. Moreover, of the 8 sex-biased genes at these loci, 4 have been directly linked to monogenic disorders of lipid metabolism and show an expression profile in females (elevated expression of ABCA1, APOA5 and LDLR; reduced expression of LIPC) that is consistent with the lower female risk of coronary artery disease. Female-biased expression was also observed for CYP7A1, which is activated by drugs used to treat hypercholesterolemia. Several sex-biased drug-metabolizing enzyme genes were identified, including members of the CYP, UGT, GPX and ALDH families. Half of 879 mouse orthologs, including many genes of lipid metabolism and homeostasis, show growth hormone-regulated sex-biased expression in mouse liver, suggesting growth hormone might play a similar regulatory role in human liver. Finally, the evolutionary rate of protein coding regions for human-mouse orthologs, revealed by dN/dS ratio, is significantly higher for genes showing the same sex-bias in both species than for non-sex-biased genes. These findings establish that human hepatic sex differences are widespread and affect diverse cell metabolic processes, and may help explain sex differences in lipid profiles associated with sex differential risk of coronary artery disease
Seismic vulnerability and risk assessment of historic masonry buildings
Seismic risk evaluation of built-up areas involves analysis of the level of earthquake hazard of the region, building vulnerability and exposure. Within this approach that defines seismic risk, building vulnerability assessment assumes great importance, not only because of the obvious physical consequences in the eventual occurrence of a seismic event, but also because it is the one of the few potential aspects in which engineering research can intervene. In fact, rigorous vulnerability assessment of existing buildings and the implementation of appropriate retrofitting solutions can help to reduce the levels of physical damage, loss of life and the economic impact of future seismic events. Vulnerability studies of urban centresshould be developed with the aim of identifying building fragilities and reducing seismic risk. As part of the rehabilitation of the historic city centre of Coimbra, a complete identification and inspection survey of old masonry buildings has been carried out. The main purpose of this research is to discuss vulnerability assessment methodologies, particularly those of the first level, through the proposal and development of a method previously used to determine the level of vulnerability, in the assessment of physical damage and its relationship with seismic intensity
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