274 research outputs found
Post-GWAS functional characterisation of colorectal cancer risk loci
Large bowel cancer, or colorectal cancer (CRC) is the third most common cause of
cancer worldwide and the fourth biggest cause of cancer mortality. Twin studies have
shown that the heritable contribution is ~35%, with ~5% of cases due to rare, high-penetrance
mutations. In the last decade, the use of genome-wide association studies
on large, well-characterised case-control cohorts of CRC has facilitated the
identification of over 25 common genetic variants that carry with them an increased
predisposition to colorectal cancer, invoking the common-disease common variant
paradigm. As almost all of these variants lie within non-coding regions, the
underlying causal mechanism is to-date poorly understood for the majority of these
loci, and it is thought that they mediate risk by influencing gene expression levels.
To test this hypothesis, an agnostic approach that utilises expression quantitative trait
loci (eQTL) analysis was first carried on 115 normal colorectal mucosa samples and
59 peripheral blood mononuclear cells (PBMC). As these heritable variation on gene
expression are likely to be subtle, there is a strong emphasis on the technical
methodology to minimise experimentally-induced non-biological variations,
including the extraction of high-quality RNA from primary tissue, the selection and
validation of reference genes for normalisation of gene expression quantification, as
well as internal validation of the samples and data processing. Thereafter, the
association between the 25 CRC risk variants and the expression of their cis-genes
were examined systematically, demonstrating that ten of these variants are also
tissue-specific eQTLs. This intermediate phenotype strongly suggests that they
confer risk, at least in part, by modifying regulatory mechanisms. One of the best
eQTL associations (Xp22.2) is investigated in further detail to reveal a novel indel
polymorphism (Indel24) at the distal promoter region of target gene SHROOM2 that
influenced both transcript abundance and CRC risk more than the original tagging
SNP. Functional verification with gene reporter assays indicated that Indel24
displays differential allelic control over transcriptional activity. Further in silico
analysis and mutations to the reporter gene constructs provided evidence that Indel24
modulates transcription by modifying the spacing between CCAAT motifs and the
consequent binding affinity of NF-Y transcription factor. siRNA depletion of NF-Y
was associated with a reduction in transcriptional activity of the Indel24 gene
construct as well as endogenous SHROOM2, which is strongly supportive of the
interaction between Indel24 and NF-Y in the transcriptional activation of
SHROOM2. Preliminary evidence is suggestive of SHROOM2 being expressed at the
top of the intestinal epithelial crypt and playing a role in cell cycle regulation.
Hypothesis-driven approaches can also be of utility in demonstrating functionality of
CRC risk variants, complementing the hypothesis-free approach of eQTL analysis.
Guided by a recently discovered gene-environment interaction between the 16q22.1
risk variant and circulating vitamin D levels, the influence of the rs9929218 SNP on
CDH1 gene expression was examined, in relation to the expression of putative
regulatory genes derived from in silico analysis and studies of other target genes.
Although there was no direct association between rs9929218 and CDH1 expression,
there were multiple two-way interactions that were together suggestive of rs9929218
influencing the VDR/FOXO4 regulation of CDH1. This provides functional support
for the mechanism underlying the epidemiological observation of the gene-environment
interaction between 16q22.1 and vitamin D, and demonstrates a
candidate-based approach in deciphering the link between genetic locus and CRC
susceptibility.
In summary, the research presented in this thesis has validated the experimental
rationale of utilising expression studies of normal colorectal mucosa to hone in on
the molecular mechanisms and susceptibility genes underlying the association
between common genetic variation and CRC risk
Antiviral biflavonoids from Radix Wikstroemiae (Liaogewanggen)
<p>Abstract</p> <p>Background</p> <p><it>Radix Wikstroemiae </it>is a common Chinese herbal medicine. The ethyl acetate fraction of the ethanolic extract of <it>W. indica </it>possesses potent <it>in vitro </it>antiviral activity against respiratory syncytial virus (RSV). This study aims to identify the antiviral components of the active fraction.</p> <p>Methods</p> <p>The active fraction of the <it>Radix Wikstroemiae </it>extract was isolated with chromatographic methods such as silica gel, Sephadex LH-20 and semi-preparative high performance liquid chromatography (HPLC) columns. The structures of the isolated compounds were determined based on spectroscopic analyses. The <it>in vitro </it>antiviral activity of the compounds against RSV was tested with the cytopathic effect (CPE) reduction assay and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method.</p> <p>Results</p> <p>Four biflavonoids, namely neochamaejasmin B, genkwanol B, genkwanol C and stelleranol, were isolated and characterized. Genkwanol B, genkwanol C and stelleranol, which are stereo isomers of spirobiflavonoids, showed potent anti-RSV activity whereas neochamaejasmin B did not.</p> <p>Conclusion</p> <p>Neochamaejasmin B, genkwanol B, genkwanol C and stelleranol were isolated from <it>Radix Wikstroemiae </it>and the complete absolute configurations of five chiral carbons in stelleranol were substantiated for the first time. Furthermore, the anti-RSV activity of genkwanol B, genkwanol C and stelleranol was reported for the first time.</p
The impact of green fnance on environmental degradation in BRI region
The Belt and Road Initiative (BRI) is one of the largest infrastructure projects in the world, accounting for more than 30% of global GDP and 60% of world population. The economic growth of BRI member countries can be improved signifcantly, attributable to the success‑fulness of the infrastructure projects. The increased economic growth indirectly leads to higher energy consumption and environmental damage. In response to this, the BRI estab‑
lished a new concept and version of the project, namely green BRI. Thus, this study aims to examine if green fnance plays a signifcant role in mitigating environmental degradation in the BRI region. Utilising a Generalised Method of Moments approach, we fnd green fnance is negatively and signifcantly correlated with environmental degradation, suggest‑ing green fnance play an essential role to reduce the deterioration of environmental qual‑
ity, while enhancing economic growth at the same time. In conclusion, BRI member states should continue promoting green fnance by implementing incentive schemes, such as
subsidising interest rates for the green loan, reducing corporate tax and establishing green credit guarantee scheme. Besides, in order simultaneously enhance economic growth, pro‑mote sustainability and achieve the 2030 Sustainable Development Goals, both governments and private sector should work hand in hand to promote green transformation of BRI
Car navigation system (mapping system)
The car navigation system naturally links with the Global Positioning System (GPS).It is increasingly being used by the road traffic users to help them in navigating to their
destination.In this research, the basic operations of car navigation are being discussed in detail.Besides that, this research also discussed the fabrication of car navigation system by having to take the Garmin Car Navigation product as the basic sample.By referring to the academic literature and the internet resources, this research reveals
the expected fabrication process of a car navigation product.This knowledge is a small step in understanding the basic operation concepts and assembly of a car navigation system
The Body Shop "Forever Against Animal Testing”
Body Shop is a well-known cruelty-free cosmetics brand company. This research paper explores how Body Shop is running the campaign 'forever against animal testing' and raising its voice for banning animal testing in cosmetics. The Body Shop has been advocating for animal rights since 1989. Qualitative analysis techniques have been used in this research paper and information is obtained through a questioner focused on convenient sampling. We have discovered in our research that most consumers do not want to purchase goods which are created by harming animals. In manufacturing cosmetics, we say companies must use alternative artificial testing like Body Shop
Differential genetic influences over colorectal cancer risk and gene expression in large bowel mucosa:Topographical differences in colorectal cancer risk loci eQTLs
The Early Clinical Features of Dengue in Adults: Challenges for Early Clinical Diagnosis
Dengue infection in adults has become increasingly common throughout the world. As most of the clinical features of dengue have been described in children, we undertook a prospective study to determine the early symptoms and signs of dengue in adults. We show here that, overall, dengue cases presented with high rates of symptoms listed in the WHO 1997 or 2009 classification schemes for probable dengue fever thus resulting in high sensitivities of these schemes when applied for early diagnosis. However, symptoms such as myalgia, arthralgia, retro-orbital pain and mucosal bleeding were less frequently reported in older adults. This trend resulted in reduced sensitivity of the WHO classification schemes in older adults even though they showed increased risks of hospitalization and severe dengue. Instead, we suggest that older adults who present with fever and leukopenia should be tested for dengue, even in the absence of other symptoms. This could be useful for early clinical diagnosis in older adults so that they can be monitored and treated for severe dengue, which is especially important when an antiviral drug becomes available
Transgenic Cry1Ab Rice Does Not Impact Ecological Fitness and Predation of a Generalist Spider
Background: The commercial release of rice genetically engineered to express a Cry1Ab protein from Bacillus thuringiensis (Bt) for control of Lepidoptera in China is a subject of debate. One major point of the debate has focused on the ecological safety of Bt rice on nontarget organisms, especially predators and parasitoids that help control populations of insect pests. Methodology/Principal Findings: A tritrophic bioassay was conducted to evaluate the potential impact of Cry1Abexpressing rice on fitness parameters of a predaceous ground spider (Pardosa pseudoannulata (Bösenberg et Strand)) that had fed on Bt rice-fed brown planthopper (Nilaparvata lugens (Sta˚l)) nymphs. Survival, development time and fecundity of this spider were not different when they were fed with Bt rice-fed or non-Bt rice-fed prey. Furthermore, ELISA and PCR gut assays, as well as a functional response trial, indicated that predation by P. pseudoannulata was not significantly different in Bt rice or non-Bt rice fields. Conclusions/Significance: The transgenic Cry1Ab rice lines tested in this study had no adverse effects on the survival, developmental time and fecundity of P. pseudoannulata in the laboratory or on predation under field conditions. Thi
Seroepidemiology of coxsackievirus A6, coxsackievirus A16, and Enterovirus 71 infections among children and adolescents in Singapore, 2008-2010
10.1371/journal.pone.0127999PLoS ONE105e012799
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