50 research outputs found
A Method for Quantitative Analysis of Standard and High-Throughput qPCR Expression Data Based on Input Sample Quantity
Over the past decade rapid advances have occurred in the understanding of RNA expression and its regulation. Quantitative polymerase chain reactions (qPCR) have become the gold standard for quantifying gene expression. Microfluidic next generation, high throughput qPCR now permits the detection of transcript copy number in thousands of reactions simultaneously, dramatically increasing the sensitivity over standard qPCR. Here we present a gene expression analysis method applicable to both standard polymerase chain reactions (qPCR) and high throughput qPCR. This technique is adjusted to the input sample quantity (e.g., the number of cells) and is independent of control gene expression. It is efficiency-corrected and with the use of a universal reference sample (commercial complementary DNA (cDNA)) permits the normalization of results between different batches and between different instruments – regardless of potential differences in transcript amplification efficiency. Modifications of the input quantity method include (1) the achievement of absolute quantification and (2) a non-efficiency corrected analysis. When compared to other commonly used algorithms the input quantity method proved to be valid. This method is of particular value for clinical studies of whole blood and circulating leukocytes where cell counts are readily available
The AGTR1 gene A1166C polymorphism as a risk factor and outcome predictor of primary intracerebral and aneurysmal subarachnoid hemorrhages
Associations between the angiotensin II type 1 receptor (AGTR1) gene A1166C polymorphism
and hypertension, aortic abdominal aneurysms (as a risk factor) as well as cardiovascular
disorders (as a risk factor and an outcome predictor) have been demonstrated. We aimed to
investigate the role of this polymorphism as risk factors and outcome predictors in primary
intracerebral hemorrhage (PICH) and aneurysmal subarachnoid hemorrhage (aSAH).
We have prospectively recruited 1078 Polish participants to the study: 261 PICH patients,
392 aSAH patients, and 425 unrelated control subjects. The A1166C AGTR1 gene polymorphism was studied using the tetra-primer ARMS-PCR method. Allele and genotype frequencies were compared with other ethnically different populations.
The A1166C polymorphism was not associated with the risk of PICH or aSAH. Among the
aSAH patients the AA genotype was associated with a good outcome, defined by a Glasgow
Outcome Scale of 4 or 5 (p < 0.02). The distribution of A1166C genotypes in our cohort did not
differ from other white or other populations of European descent.
In conclusion, we found an association between the A1166C AGTR1 polymorphism and
outcome of aSAH patients, but not with the risk of PICH or aSAH
The AGTR1 gene A1166C polymorphism as a risk factor and outcome predictor of primary intracerebral and aneurysmal subarachnoid hemorrhages
Associations between the angiotensin II type 1 receptor (AGTR1) gene A1166C polymorphism and hypertension, aortic abdominal aneurysms (as a risk factor) as well as cardiovascular disorders (as a risk factor and an outcome predictor) have been demonstrated. We aimed to investigate the role of this polymorphism as risk factors and outcome predictors in primary intracerebral hemorrhage (PICH) and aneurysmal subarachnoid hemorrhage (aSAH).
We have prospectively recruited 1078 Polish participants to the study: 261 PICH patients, 392 aSAH patients, and 425 unrelated control subjects. The A1166C AGTR1 gene polymorphism was studied using the tetra-primer ARMS-PCR method. Allele and genotype frequencies were compared with other ethnically different populations.
The A1166C polymorphism was not associated with the risk of PICH or aSAH. Among the aSAH patients the AA genotype was associated with a good outcome, defined by a Glasgow Outcome Scale of 4 or 5 (p<0.02). The distribution of A1166C genotypes in our cohort did not differ from other white or other populations of European descent.
In conclusion, we found an association between the A1166C AGTR1 polymorphism and outcome of aSAH patients, but not with the risk of PICH or aSAH
Polimorfizm –455G/A genu β-fibrynogenu a ryzyko udaru niedokrwiennego w populacji polskiej
Background and purpose: Ischaemic stroke is considered to
be multifactorial and interactions between environmental and
genetic factors play an important role. Although vascular risk
factors are well known, the genetic ones are still undiscover -
ed. In the present study, we assessed the significance of the
β-fibrinogen –455G/A gene polymorphism and the risk of
ischaemic stroke in a Polish population.
Material and methods: 426 ischaemic stroke patients classified according to stroke aetiologies (small vessel disease, large
vessel disease or cardioembolic stroke) and 234 controls were
included in the study. The association of the β-fibrinogen
genotypes with ischaemic stroke was tested using logistic
regression analysis under dominant, recessive or additive
models of inheritance.
Results: The allele and genotype distributions of the β-fibri -
nogen –455G/A gene polymorphism did not differ significantly between patients and controls (patients: G – 75%,
GG – 56.6%, GA – 36.8%, AA – 6.6%; controls: G – 73.7%,
GG – 57.3%, GA – 32.9%, AA – 9.8%; p > 0.05, χ2). In
addition, logistic regression analysis adjusted for the known
risk factors, i.e. hypertension, ischaemic heart disease, myocardial infarction, hypercholesterolaemia, diabetes mellitus and
smoking, did not show a role of the studied polymorphism
in ischaemic stroke. Conclusions: The β-fibrinogen –455G/A gene polymorphism
is not a risk factor for ischaemic stroke in a Polish population
Polimorfizm –455G/A genu β-fibrynogenu a ryzyko udaru niedokrwiennego w populacji polskiej
Background and purpose
Ischaemic stroke is considered to be multifactorial and interactions between environmental and genetic factors play an important role. Although vascular risk factors are well known, the genetic ones are still undiscovered. In the present study, we assessed the significance of the β-fibrinogen –455G/A gene polymorphism and the risk of ischaemic stroke in a Polish population.
Material and methods
426 ischaemic stroke patients classified according to stroke aetiologies (small vessel disease, large vessel disease or cardioembolic stroke) and 234 controls were included in the study. The association of the β-fibrinogen genotypes with ischaemic stroke was tested using logistic regression analysis under dominant, recessive or additive models of inheritance.
Results
The allele and genotype distributions of the β-fibrinogen –455G/A gene polymorphism did not differ significantly between patients and controls (patients: G – 75%, GG – 56.6%, GA – 36.8%, AA – 6.6%; controls: G – 73.7%, GG – 57.3%, GA – 32.9%, AA – 9.8%; p > 0.05, χ2). In addition, logistic regression analysis adjusted for the known risk factors, i.e. hypertension, ischaemic heart disease, myocardial infarction, hypercholesterolaemia, diabetes mellitus and smoking, did not show a role of the studied polymorphism in ischaemic stroke.
Conclusions
The β-fibrinogen –455G/A gene polymorphism is not a risk factor for ischaemic stroke in a Polish population.Wstęp i cel pracy
Etiologia udaru niedokrwiennego mózgu jest wieloczynnikowa. Istotną rolę odgrywają w niej interakcje pomiędzy czynnikami środowiskowymi i genetycznymi. Naczyniowe czynniki ryzyka udaru mózgu są dość dobrze poznane, natomiast rola czynników genetycznych pozostaje wciąż niejasna. W prezentowanym badaniu oceniano znaczenie polimorfizmu –455G/A genu β-fibrynogenu w kontekście ryzyka wystąpienia udaru niedokrwiennego mózgu w populacji polskiej.
Materiał i metody
Do badania włączono 426 chorych na udar niedokrwienny mózgu sklasyfikowanych zgodnie z etiologią udaru (choroba małych naczyń, choroba dużych naczyń lub udar sercowozatorowy) oraz 234 osoby z grupy kontrolnej. Związek pomiędzy badanym polimorfizmem a udarem niedokrwiennym mózgu został zbadany przy użyciu regresji logistycznej w dominującym, recesywnym i addytywnym modelu dziedziczenia.
Wyniki
Nie stwierdzono istotnej różnicy w rozkładzie alleli i genotypów polimorfizmu –455G/A genu β-fibrynogenu pomiędzy pacjentami a osobami z grupy kontrolnej (pacjenci: G – 75%, GG – 56,6%, GA – 36,8%, AA – 6,6%; grupa kontrolna: G – 73,7%, GG – 57,3%, GA – 32,9%, AA – 9,8 %; p > 0,05, test χ2). Ponadto w modelu regresji logistycznej uwzględniającym wpływ znanych czynników ryzyka, takich jak: nadciśnienie tętnicze, choroba niedokrwienna serca, zawał mięśnia sercowego, hipercholesterolemia, cukrzyca i palenie tytoniu, nie wykazano roli badanego polimorfizmu w udarze niedokrwiennym mózgu.
Wnioski
Polimorfizm –455G/A genu β-fibrynogenu nie jest czynnikiem ryzyka udaru niedokrwiennego mózgu w populacji polskiej
Vascular cognitive impairment linked to brain endothelium inflammation in early stages of heart failure in mice
Background
Although advanced heart failure (
HF
) is a clinically documented risk factor for vascular cognitive impairment, the occurrence and pathomechanisms of vascular cognitive impairment in early stages of
HF
are equivocal. Here, we characterize vascular cognitive impairment in the early stages of
HF
development and assess whether cerebral hypoperfusion or prothrombotic conditions are involved.
Methods and Results
Tgαq*44 mice with slowly developing isolated
HF
triggered by cardiomyocyte‐specific overexpression of G‐αq*44 protein were studied before the end‐stage
HF
, at the ages of 3, 6, and 10 months: before left ventricle dysfunction; at the stage of early left ventricle diastolic dysfunction (with preserved ejection fraction); and left ventricle diastolic/systolic dysfunction, respectively. In 6‐ to 10‐month‐old but not in 3‐month‐old Tgαq*44 mice, behavioral and cognitive impairment was identified with compromised blood‐brain barrier permeability, most significantly in brain cortex, that was associated with myelin sheet loss and changes in astrocytes and microglia. Brain endothelial cells displayed increased E‐selectin immunoreactivity, which was accompanied by increased amyloid‐β
1‐42
accumulation in piriform cortex and increased cortical oxidative stress (8‐
OH
dG immunoreactivity). Resting cerebral blood flow measured by magnetic resonance imaging in vivo was preserved, but ex vivo
NO
‐dependent cortical arteriole flow regulation was impaired. Platelet hyperreactivity was present in 3‐ to 10‐month‐old Tgαq*44 mice, but it was not associated with increased platelet‐dependent thrombogenicity.
Conclusions
We report for the first time that vascular cognitive impairment is already present in the early stage of
HF
development, even before left ventricle systolic dysfunction. The underlying pathomechanism, independent of brain hypoperfusion, involves preceding platelet hyperreactivity and brain endothelium inflammatory activation.
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Atrial fibrillation genetic risk differentiates cardioembolic stroke from other stroke subtypes
AbstractObjectiveWe sought to assess whether genetic risk factors for atrial fibrillation can explain cardioembolic stroke risk.MethodsWe evaluated genetic correlations between a prior genetic study of AF and AF in the presence of cardioembolic stroke using genome-wide genotypes from the Stroke Genetics Network (N = 3,190 AF cases, 3,000 cardioembolic stroke cases, and 28,026 referents). We tested whether a previously-validated AF polygenic risk score (PRS) associated with cardioembolic and other stroke subtypes after accounting for AF clinical risk factors.ResultsWe observed strong correlation between previously reported genetic risk for AF, AF in the presence of stroke, and cardioembolic stroke (Pearson’s r=0.77 and 0.76, respectively, across SNPs with p < 4.4 × 10−4 in the prior AF meta-analysis). An AF PRS, adjusted for clinical AF risk factors, was associated with cardioembolic stroke (odds ratio (OR) per standard deviation (sd) = 1.40, p = 1.45×10−48), explaining ∼20% of the heritable component of cardioembolic stroke risk. The AF PRS was also associated with stroke of undetermined cause (OR per sd = 1.07, p = 0.004), but no other primary stroke subtypes (all p > 0.1).ConclusionsGenetic risk for AF is associated with cardioembolic stroke, independent of clinical risk factors. Studies are warranted to determine whether AF genetic risk can serve as a biomarker for strokes caused by AF.</jats:sec