ABSTRACT
BACKGROUND: Hemodynamic compromise has been observed in patients with acute small subcortical infarction (SSI), and it may play a critical role in the development of early neurological deterioration (END). This study aimed to evaluate the clinical relevance and underlying pathology of hemodynamic compromise in SSI using MRI-based neuroimaging markers. METHODS: We retrospectively analyzed data and imaging of previous prospective studies. Patients with acute SSI in penetrating artery territories were recruited, all of whom underwent perfusion MRI within 24 h of stroke onset. We examined the relationships among perfusion defects and neuroimaging markers of small vessel disease, including white matter hyperintensities, cerebral microbleeds, enlarged perivascular spaces (EPVSs) and lacunes. RESULTS: One hundred and seven patients were recruited, of whom 21 (19.6%) had END and 55 (51.4%) had visible perfusion defects. Patients with perfusion defects were associated with a higher rate of END (34.5% vs. 3.8%; p < 0.001), higher initial National Institutes of Health Stroke Scale scores (5.4 vs. 3.4, p < 0.001), higher rate of branch atheromatous disease (61.8% vs. 34.6%, p = 0.005) and higher rate of poor outcome at 3 months (40.0% vs. 5.4%; p = 0.005). In multiple logistic regression, perfusion defects were significantly associated with basal ganglia EPVS scores (adjusted odds ratio [aOR]: 3.93; 95% confidence interval [CI]: 1.76-8.77; p = 0.001) and branch atheromatous disease (aOR: 2.64; 95% CI: 1.06-6.60; p = 0.037). CONCLUSION: Hemodynamic compromise in acute SSI was highly related to the development of END, basal ganglia EPVS and branch atheromatous disease, suggesting the correlation with underlying pathologies of hypertensive arteriopathy and atherosclerosis.
Subject(s)
Clinical Relevance , Stroke , Humans , Retrospective Studies , Magnetic Resonance Imaging/methods , Cerebral Infarction/diagnostic imaging , Neuroimaging/methods , HemodynamicsABSTRACT
The hemodynamic changes of acute small subcortical infarction (SSI) are not well understood. We evaluate the hemodynamic changes and collaterals in acute SSI using perfusion magnetic resonance imaging (MRI). A total of 103 patients with acute SSI in penetrating artery territories were recruited and underwent MRI within 24 h of stroke onset. Using 4D dynamic perfusion MRI, they were divided into three patterns: 25 (24%) with normal perfusion, 31 (30%) with compensated perfusion, and 47 (46%) with hypoperfusion. The development of anterograde or retrograde collaterals was also evaluated. Patients with hypoperfusion pattern had the highest rate of early neurological deterioration (32%, p = 0.007), the largest initial and final infarction volumes (p < 0.001 and p = 0.029), the lowest relative cerebral blood flow (0.63, p < 0.001), and the lowest rate of anterograde and retrograde collaterals (19%, p < 0.001; 66%, p = 0.002). The anterograde collaterals were associated with higher relative cerebral blood volume (0.91 vs. 0.77; p = 0.024) and a higher rate of deep cerebral microbleeds (48 vs. 21%; p = 0.028), whereas retrograde collaterals were associated with higher systolic and diastolic blood pressure (p = 0.031 and 0.020), smaller initial infarction volume (0.81 vs. 1.34 ml, p = 0.031), and a higher rate of lobar cerebral microbleeds (30 vs. 0%; p = 0.013). Both anterograde and retrograde collaterals may play a critical role in maintaining cerebral perfusion and can have an impact on patient clinical outcomes. Further studies are warranted to verify these findings and to investigate effective treatments.
Subject(s)
Cerebral Infarction , Stroke , Cerebral Hemorrhage , Cerebral Infarction/diagnostic imaging , Cerebrovascular Circulation/physiology , Collateral Circulation/physiology , Humans , Magnetic Resonance Imaging/methods , PerfusionABSTRACT
OBJECTIVE: In acute ischemic stroke, early neurological deterioration (END) may occur in up to one-third of patients. However, there is still no satisfying or comprehensive predictive model for all the stroke subtypes. We propose a practical model to predict END using magnetic resonance imaging (MRI). METHOD: Patients with anterior circulation infarct were recruited and they underwent an MRI within 24 hours of stroke onset. END was defined as an elevation of ≥2 points on the National Institute of Health Stroke Scale (NIHSS) within 72 hours of stroke onset. We examined the relationships of END to individual END models, including: A, infarct swelling; B, small subcortical infarct; C, mismatch; and D, recurrence. RESULTS: There were 163 patients recruited and 43 (26.4%) of them had END. The END models A, B and C significantly predicted END respectively after adjusting for confounding factors (p=0.022, p=0.007 and p<0.001 respectively). In END model D, we examined all imaging predictors of Recurrence Risk Estimator (RRE) individually and only the "multiple acute infarcts" pattern was significantly associated with END (p=0.032). When applying END models A, B, C and D, they successfully predicted END (p<0.001; odds ratio: 17.5[95% confidence interval: 5.1- 60.8]), with 93.0% sensitivity, 60.0% specificity, 45.5% positive predictive value and 96.0% negative predictive value. CONCLUSION: The results demonstrate that the proposed model could predict END in all stroke subtypes of anterior circulation infarction. It provides a practical model for clinical physicians to select high-risk patients for more aggressive treatment to prevent END.
Subject(s)
Diffusion Magnetic Resonance Imaging/methods , Nervous System Diseases/diagnostic imaging , Nervous System Diseases/etiology , Stroke/complications , Aged , Aged, 80 and over , Brain Ischemia/complications , Female , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Predictive Value of Tests , Sensitivity and Specificity , Stroke/etiologyABSTRACT
The low-density lipoprotein receptor-related protein 1 (LRP1) gene is associated with increased levels of plasma factor VIII (FVIII). We aimed to explore eight functional genetic LRP1 variants for their potential roles in regulating FVIII levels and acute ischemic stroke (AIS). This genetic association study enrolled 192 patients with AIS and 134 controls. There were no significant differences in the genetic frequency of the eight functional single-nucleotide polymorphisms (SNPs) between the control and AIS groups. However, while analyzing the association between the eight SNPs and plasma FVIII levels, subjects with T/T genotype of rs1800137 (vs. CC+CT) were found to be associated with higher FVIII levels (23.5IU/dL; 95% confidence interval, 7.4-39.5IU/dL; P=0.0044) after adjusting for age, gender, estimated glomerular filtration rate, O blood type, inflammatory state, and body mass index. An analysis of the mRNA stability and abundance was designed and performed using minigene system transfected into HepG2 cells to assess the possible differences in mRNA stabilities between rs1800137 CC (rs1800137C) and TT (rs1800137T) genotypes. Site-directed mutagenesis revealed that rs1800137T accounts for the observed decrease in mRNA stability. The SNP rs1800137, located in exon 8, has been identified as an exon-splicing enhancer in silico. However, alternative splicing of LRP1 without inclusion of exon 8 was not identified. In transfected HepG2 cells, cycloheximide slowed down the degradation of the rs1800137T-containing minigene. These results demonstrate that synonymous SNP rs1800137 can lead to increased plasma FVIII levels due to decreased mRNA stability via translation-dependent mRNA degradation associated with codon optimality.
Subject(s)
Brain Ischemia , Factor VIII , Low Density Lipoprotein Receptor-Related Protein-1 , Polymorphism, Single Nucleotide , RNA Stability/genetics , RNA, Messenger , Stroke , Alternative Splicing/genetics , Brain Ischemia/genetics , Brain Ischemia/metabolism , Brain Ischemia/pathology , Factor VIII/biosynthesis , Factor VIII/genetics , Female , Hep G2 Cells , Humans , Low Density Lipoprotein Receptor-Related Protein-1/genetics , Low Density Lipoprotein Receptor-Related Protein-1/metabolism , Male , RNA, Messenger/genetics , RNA, Messenger/metabolism , Stroke/genetics , Stroke/metabolism , Stroke/pathologyABSTRACT
BACKGROUND: The risk of symptomatic infarct swelling has been reported to be higher in patients treated with recombinant tissue plasminogen activator (rt-PA). The aim of this study was to evaluate the timing of symptomatic infarct swelling after rt-PA treatment. METHODS: We retrospectively analyzed 14 868 patients with acute ischemic stroke from a stroke registry databank. We recruited patients with massive middle cerebral artery (MCA) infarction and symptomatic infarct swelling and excluded those with parenchymal or symptomatic hemorrhage. Multiple linear regression and multivariate logistic regression analyses were used to estimate the impact of rt-PA on the timing of symptomatic infarct swelling. RESULTS: A total of 23 patients with rt-PA treatment and 117 patients without rt-PA treatment were included. The rt-PA treatment group had a lower rate of coronary artery disease (8.7% vs 32.5%; P = .023), lower severity of baseline National Institutes of Health Stroke Scale score (19 vs 23; P = .014), shorter duration of infarct swelling (27.6 vs 45.4 hours; P < .001), and higher rate of hemicraniectomy surgery (65.2% vs 28.2%; P =.001) than those without rt-PA treatment. After adjusting for variables in multiple linear regression analysis, rt-PA treatment and an elevated C-reactive protein level were associated with early symptomatic infarct swelling ( P = .014 and P = .041, respectively). The rt-PA treatment was an independent factor related to early symptomatic infarct swelling within 36 hours ( P = .005; odds ratio [OR]: 5.3; confidence interval [CI]: 1.65-17.0) or 48 hours ( P = .009; OR: 16.4; CI: 2.00-134). CONCLUSION: Intravenous rt-PA treatment may hasten the onset of cerebral edema and subsequent cerebral herniation in large MCA territory infarction.
Subject(s)
Infarction, Middle Cerebral Artery/pathology , Thrombolytic Therapy/adverse effects , Tissue Plasminogen Activator/adverse effects , Brain Edema , C-Reactive Protein/analysis , Case-Control Studies , Coronary Artery Disease , Humans , Infarction, Middle Cerebral Artery/drug therapy , Registries , Retrospective Studies , Severity of Illness Index , Stroke/pathology , Tissue Plasminogen Activator/therapeutic useABSTRACT
As the first step of ongoing efforts to investigate the genes responsible for the biosynthesis of steroidal saponins in the medicinal plant Ornithogalum caudatum, this investigation reported the cDNA isolation, prokaryotic expression and functional characterization of squalene synthase (SQS) gene from O. caudatum for the first time. Specifically, two unigenes showing high sequence identity to SQS were retrieved from RNA-Taq data, and then a full-length OcSQS1 corresponding to the two unigenes was isolated from O. caudatum genome by a nested PCR assay. The open reading frame of OcSQS1 was 1230 bp and encoded a polypeptide of 409 aa. OcSQS1 was predicted to be a membrane-bound protein with at least four conserved motifs associated with binding, regulatory and catalytic activities of OcSQS1 and two transmembrane domains. Next, many attempts to generate soluble OcSQS1 in heterologous Escherichia coli were made, including optimization of expression conditions, application of varied expression plasmids with different tags, secretory peptides and molecular chaperones, and truncated mutation of OcSQS1. Finally, the successful availability of a soluble, truncated OcSQS1 mutant was achieved by combinational use of the utensils from the vast genetic toolbook. Moreover, this truncated OcSQS1 mutant retained the folding capability as well as its catalytic activity, converting FPP to form squalene. Importantly, the present research tentatively verified the involvement of the second transmembrane domain in the proper folding of the recombinant OcSQS1 protein.
Subject(s)
Cloning, Molecular , DNA, Complementary , Escherichia coli/metabolism , Farnesyl-Diphosphate Farnesyltransferase , Ornithogalum/genetics , Plant Proteins , DNA, Complementary/genetics , DNA, Complementary/isolation & purification , Escherichia coli/genetics , Farnesyl-Diphosphate Farnesyltransferase/biosynthesis , Farnesyl-Diphosphate Farnesyltransferase/chemistry , Farnesyl-Diphosphate Farnesyltransferase/genetics , Farnesyl-Diphosphate Farnesyltransferase/isolation & purification , Ornithogalum/enzymology , Plant Proteins/biosynthesis , Plant Proteins/chemistry , Plant Proteins/genetics , Plant Proteins/isolation & purification , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purificationABSTRACT
Despite advances in imaging techniques and detailed examinations to determine the etiology of a stroke, the cause still remains undetermined in about one fourth of all ischemic strokes. The aim of this prospective study was to determine whether perfusion magnetic resonance imaging (MRI) can differentiate cardioembolic stroke from large artery atherosclerosis (LAA). We recruited 17 cardioembolic stroke and 22 LAA stroke patients, who were classified according to the Trial of Org 10172 in Acute Stroke Treatment and underwent perfusion MRI within 24 hours after the onset of stroke. The patients with cardioembolic stroke had more severe initial stroke severity and larger volumes of initial and final infarct compared to those with LAA stroke. Receiver operating characteristic curve analysis showed that the ratio of time to maximum of the residual curve (Tmax) volume for a 2-, 3-, 4- or 5-s lag over Tmax volume for a 8s lag all had excellent area under the curve values (> 0.9) to predict cardioembolic stroke. After adjusting for initial National Institute of Health Stroke Scale scores, a threshold of 3.73 for (Tmax > 4s volume)/(Tmax > 8s volume) had the highest odds ratio to predict cardioembolic stroke (p=0.012; odds ratio: 58.5; 95% confident interval: 2.5-1391.1), with 87.5% sensitivity and 94.4% specificity. In conclusion, perfusion MRI could be a reliable tool to identify cardioembolic stroke with its lower collateral. This is important as it could be used to reveal the exact mechanism and provide supportive evidence to classify a stroke.
Subject(s)
Brain Ischemia/diagnosis , Brain/blood supply , Heart Diseases/complications , Magnetic Resonance Angiography , Stroke/diagnosis , Aged , Aged, 80 and over , Brain/pathology , Brain Ischemia/complications , Brain Ischemia/pathology , Cerebrovascular Circulation/physiology , Embolism/complications , Female , Humans , Magnetic Resonance Angiography/methods , Male , Middle Aged , Prospective Studies , Stroke/complications , Stroke/therapy , Thrombolytic Therapy/methodsABSTRACT
The purpose of this study was to analyze the outcomes and complications between stroke subtypes after intravenous thrombolysis. A total of 471 patients with acute ischemic stroke after intravenous thrombolysis from January 2007 to April 2014 were enrolled and classified according to the Trial of Org 10172 in Acute Stroke Treatment. A multivariate logistic regression model was used to evaluate the outcomes and complications among stroke subtypes after adjusting for baseline variables. Of the 471 patients, 117 (25.1 %) had large-artery atherosclerosis (LAA), 148 (31.8 %) had cardioembolism (CE), 82 (17.6 %) had small vessel disease (SVD), 119 (25.5 %) had undetermined etiology, and 5 (1.1 %) had other determined etiology. The patients with SVD had the mildest initial stroke severity and highest ratio of good and favorable outcomes, whereas those with CE had a higher rate of symptomatic intracranial hemorrhage (sICH) than those with SVD. After adjusting for confounding factors, the ratio of favorable outcome in the patients with SVD stroke was higher than in those with LAA. SVD was associated with a significantly lower rate of any hemorrhage compared to other stroke subtypes, whereas there were no differences in sICH or mortality between stroke subtypes. A lower initial National Institutes of Health Stroke Scale score was associated with good and favorable outcomes, and lower rates of sICH and mortality. The patients with SVD after intravenous thrombolysis had better outcomes and a lower rate of hemorrhage even after adjusting for confounding factors. Stroke severity was an independent factor associated with better functional outcomes, sICH and mortality.
ABSTRACT
BACKGROUND: (2S)-Pinocembrin is a chiral flavanone with versatile pharmacological and biological activities. Its health-promoting effects have spurred on research effects on the microbial production of (2S)-pinocembrin. However, an often-overlooked salient feature in the analysis of microbial (2S)-pinocembrin is its chirality. RESULTS: Here, we presented a full characterization of absolute configuration of microbial (2S)-pinocembrin from engineered Escherichia coli. Specifically, a transcriptome-wide search for genes related to (2S)-pinocembrin biosynthesis from Ornithogalum caudatum, a plant rich in flavonoids, was first performed in the present study. A total of 104,180 unigenes were finally generated with an average length of 520 bp. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway mapping assigned 26 unigenes, representing three enzyme families of 4-coumarate:coenzyme A ligase (4CL), chalcone synthase (CHS) and chalcone isomerase(CHI), onto (2S)-pinocembrin biosynthetic pathway. A total of seven, three and one full-length candidates encoding 4CL, CHS and CHI were then verified by reverse transcription polymerase chain reaction, respectively. These candidates were screened by functional expression in E. coli individual or coupled multienzyme reaction systems based on metabolic engineering processes. Oc4CL1, OcCHS2 and OcCHI were identified to be bona fide genes encoding respective pathway enzymes of (2S)-pinocembrin biosynthesis. Then Oc4CL1, OcCHS2 and MsCHI from Medicago sativa, assembled as artificial gene clusters in different organizations, were used for fermentation production of (2S)-pinocembrin in E. coli. The absolute configuration of the resulting microbial pinocembrin at C-2 was assigned to be 2S-configured by combination of retention time, UV spectrum, LC-MS, NMR, optical rotation and circular dichroism spectroscopy. Improvement of (2S)-pinocembrin titres was then achieved by optimization of gene organizations, using of codon-optimized pathway enzymes and addition of cerulenin for increasing intracellular malonyl CoA pools. Overall, the optimized strain can produce (2S)-pinocembrin of 36.92 ± 4.1 mg/L. CONCLUSIONS: High titre of (2S)-pinocembrin can be obtained from engineered E. coli by an efficient method. The fermentative production of microbial (2S)-pinocembrin in E. coli paved the way for yield improvement and further pharmacological testing.
Subject(s)
Biosynthetic Pathways/genetics , Flavanones/metabolism , Metabolic Engineering/methods , Ornithogalum/enzymology , Ornithogalum/genetics , Transcriptome/genetics , Carbon-13 Magnetic Resonance Spectroscopy , Chromatography, High Pressure Liquid , Circular Dichroism , DNA, Complementary/genetics , DNA, Complementary/isolation & purification , Fermentation , Flavanones/chemistry , Gene Expression Regulation, Plant , Multigene Family , Proton Magnetic Resonance Spectroscopy , Recombinant Proteins/metabolismABSTRACT
BACKGROUND: The role played by hemostasis in the pathogenesis of ischemic strokes is still controversial. The activated partial thromboplastin time (APTT) measures the time necessary to generate fibrin from initiation of the intrinsic pathway. In the present study, we looked for a possible association of ischemic strokes with the shortened APTT. METHODS: The study population consisted of 154 patients with acute ischemic strokes who had been admitted from December 2013 to December 2014 to the Department of Neurology, Chiayi Chang Gung Memorial Hospital, and 71 control subjects with no history of stroke. RESULTS: In a univariate risk analysis, shortened APTT was associated with an odds ratio (OR) for acute ischemic strokes of up to 1.86 (95% confidence interval [CI], 1.06-3.29, P = .031). In a multivariate analysis using a logistic regression model including age, sex, hypertension, diabetes mellitus, and shortened APTT, shortened APTT was still found to significantly add to the risk of ischemic stroke (OR = 2.12 with 95% CI, 1.13-3.98, P = .020). Shortened APTT was also associated significantly with neurological worsening (OR = 3.72 with 95% CI 1.03-13.5, P = .046). As for stroke severity, shortened APTT was associated with an OR for moderate/severe stroke of up to 3.42 (95% CI, 1.53-7.61, P = .003). CONCLUSION: Shortened APTT is a prevalent and independent risk factor for ischemic stroke, stroke severity, and neurological worsening after acute stroke.
Subject(s)
Nervous System Diseases/etiology , Partial Thromboplastin Time , Stroke/complications , Thromboplastin/metabolism , Adult , Aged , Aged, 80 and over , Brain Ischemia/complications , Female , Humans , Lipoproteins/metabolism , Male , Middle Aged , Retrospective Studies , Stroke/etiology , Time FactorsABSTRACT
Perfusion-diffusion mismatch in magnetic resonance imaging (MRI) represents the non-core hypoperfused area in acute ischemic stroke. The mismatch has been used to predict clinical response after thrombolysis in acute ischemic stroke, but its role for predicting early neurological deterioration (END) in acute ischemic stroke without thrombolysis has not been clarified yet. In this study, we prospectively recruited 54 patients with acute non-lacunar ischemic stroke in anterior circulation without thrombolysis. All patients received the first perfusion MRI within 24 hours from stroke onset. Target mismatch profile was defined as a perfusion-diffusion mismatch ratio ≥ 1.2. END was defined as an increase of ≥ 4 points in the National Institute of Health Stroke Scale (NIHSS) score within 72 hours. There were 13 (24.1%) patients developing END, which was associated with larger infarct growth (p = 0.002), worse modified Rankin Scale (p = 0.001) and higher mortality rate at 3 months (p = 0.025). Target mismatch profiles measured by T(max) ≥ 4, 5 and 6 seconds were independent predictors for END after correcting initial NIHSS score. Among the 3 T(max) thresholds, target mismatch measured by T(max) ≥ 6 seconds had the highest odd's ratio in predicting END (p < 0.01, odd's ratio = 17), with an 80% sensitivity and a 79.5% specificity. In conclusion, perfusion-diffusion mismatch could identify the patients at high risk of early clinical worsening in acute ischemic stroke without thrombolysis.
Subject(s)
Brain Infarction/complications , Early Diagnosis , Nervous System Diseases/diagnosis , Nervous System Diseases/etiology , Aged , Aged, 80 and over , Diffusion Magnetic Resonance Imaging , Female , Humans , Male , Perfusion Imaging , Predictive Value of Tests , Retrospective StudiesABSTRACT
The role played by hemostasis in the pathogenesis of ischemic stroke is still controversial. In the present study, we looked for a possible association of ischemic stroke with the high clotting activity of factor VIII (FVIII). The study population consisted of 116 patients with acute ischemic stroke who had been admitted between September 2013 and September 2014 to the Department of Neurology, Chiayi Chang Gung Memorial Hospital, and 76 control subjects with no history of stroke. FVIII levels were higher in stroke patients as compared to controls (127.5 ± 52.5 vs. 108.4 ± 49.0 IU/dL; P = 0.012). In a univariate risk analysis, FVIII at levels above 150 IU/dL was associated with an odds ratio (OR) for ischemic stroke of up to 2.55 (95% CI, 1.20-5.42, P = 0.013). In a multivariate analysis using a logistic regression model including age, hypertension, low density lipoprotein cholesterol level, estimated glomerular filtration rate, and high FVIII (< 150 IU/dL), high FVIII was still found to significantly add to the risk of ischemic stroke (OR = 3.26 with 95% CI, 1.38-7.68, P = 0.007). As for the stroke subtypes, mean FVIII level was significantly higher in patients with cardioembolic stroke than patients with noncardioembolic stroke (156.0 ± 51.5 IU/dL vs. 124.3 ± 51.9 IU/dL). High levels of FVIII were also associated significantly with neurological worsening (OR = 3.66 with 95% CI, 1.24-10.82, P = 0.019). A high plasma level of FVIII is a prevalent and independent risk factor for ischemic stroke and neurological worsening after acute stroke.
Subject(s)
Brain Ischemia/complications , Factor VIII/metabolism , Nervous System Diseases/etiology , Stroke , Adult , Aged , Aged, 80 and over , Disability Evaluation , Female , Humans , Male , Middle Aged , Neurologic Examination , Odds Ratio , Stroke/classification , Stroke/complications , Stroke/etiologyABSTRACT
BACKGROUND: Whether a perfusion defect exists in lacunar infarct and whether it is related to early neurological deterioration (END) is still under debate. The aim of this study was to evaluate whether END in lacunar infarct is related to a perfusion defect using diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI) and perfusion MR imaging. METHODS: One hundred and forty-one consecutive patients had an MRI scan within 30 hours after onset of symptoms and 43 patients with acute lacunar infarct and classic lacunar syndrome were recruited. The MRI sequences included DWI, DTI and cerebral blood flow (CBF) maps to respectively represent the topographic locations of acute infarcts, the corticospinal tract and perfusion defects. The END was defined in reference to the National Institute of Health Stroke Scale (NIHSS) as an increase â§2 within 72 hours. Cohen's Kappa coefficient was used to examine the reliability between the 2 image readers. A multivariate logistic regression model was constructed adjusting for baseline variables. RESULTS: Ten out of the 43 patients had END. Patients having END was significantly associated with lower chances of favorable and good outcomes at 3 months (pâ=â0.01 and pâ=â0.002, respectively). END was predicted when the non-core hypoperfused area overlapped on the corticospinal tract, which is defined as the expected END profile. Cohen's Kappa coefficient between the 2 image readers to define images of expected END profiles was 0.74. In 15 patients with expected END profile, 9 had END clinically, whereas 28 patients had no expected END profile, and only 1 patient had END (p<0.0001). After adjusting for sex, the expected END profile was still associated with END (odds ratio, 42.2; pâ=â0.002). CONCLUSION: Our study demonstrated that the END in acute lacunar stroke is likely related to the transformation of non-core hypoperfused area into infarction in the anatomy of corticospinal tracts.
Subject(s)
Hemodynamics/physiology , Stroke, Lacunar/physiopathology , Aged , Cerebrovascular Circulation , Demography , Diffusion Magnetic Resonance Imaging , Diffusion Tensor Imaging , Female , Humans , Male , Time FactorsABSTRACT
Analysis of the low-density lipoprotein receptor (LDLR) gene based on the rs688 and rs5925 genetic polymorphisms has provided evidence suggesting that haplotypes related to rs688 and rs5925 are associated with ischemic cerebrovascular diseases. Both rs688 and rs5925 have been empirically identified as exon-splicing enhancers in silico, and rs688 has been shown to be a functional polymorphism that modulates LDLR exon 12 splicing efficiency both in vitro and in vivo. The aim of this study was to evaluate whether rs688 and rs5925 and their haplotypes may alter the splicing efficiency of exons 12 and 13 both in vivo and in vitro. When the minigenes were evaluated for splicing efficiency, we found that converting rs688C to the T allele reduced exon 12 splicing efficiency. In parallel, converting rs688T to the C allele increased the efficiency of exon 12 inclusion. The apparent difference in splicing efficiency was 9.36%±2.58% between the C and T alleles. When rs688C existed in the minigene, the major and minor rs5925 alleles were also sufficient to account for the differences in splicing efficiency of LDLR involving exon 13. The apparent splicing efficiency difference was 5.43%±2.87%. Sequential mutations of rs688 and rs5925 were performed to generate four different haplotypes in the LDLR minigene system. The splicing efficiencies for the haplotypes CC, CT, TC, and TT were 79.60%±1.38%, 76.68%±0.85%, 69.02%±1.79%, and 68.54%±1.38%, respectively. The splicing efficiency of the four haplotype groups differed significantly. In vivo analysis of human leukocyte samples was also compatible with in vitro analysis, indicating a mutual effect between rs688 and rs5925 in regulating LDLR splicing efficiency.
Subject(s)
Polymorphism, Single Nucleotide , RNA Splicing , RNA, Messenger/genetics , Receptors, LDL/genetics , Alleles , Alternative Splicing , Exons , HEK293 Cells , Haplotypes , Humans , Protein Isoforms/genetics , Protein Isoforms/metabolism , RNA, Messenger/metabolism , Receptors, LDL/metabolismABSTRACT
Intracranial hemorrhage is the third most common cause of cerebrovascular disease. Some polymorphisms that affect clotting factors increase the risk of thrombosis. However, few reports have analyzed the effect of polymorphisms on the hemostatic state in bleeding disorders. The low-density lipoprotein receptor (LDLR) has been shown to contribute to factor VIII (FVIII) homeostasis, which represents a link between LDLR and hemostasis. FVIII plays a pivotal role in the coagulation cascade. Patients with high levels of FVIII are at an increased risk of arterial and venous thrombosis. On the other hand, patients with insufficient FVIII tend to bleed excessively, such as in hemophilia A. In a previous study, analysis of the genetic LDLR variant rs688 provided evidence suggesting that genetic polymorphisms of rs688 are associated with thrombotic cardiovascular diseases. The current study aimed to investigate the potential role of rs688 in primary intracerebral hemorrhage (PICH). This genetic association study was conducted within an isolated Taiwanese population (447 PICH patients and 430 controls). Genotypes C/C and C/T were used as the reference genotypes, and the genotype T/T was found to be associated with a 73% decreased risk of PICH. The preliminary evidence suggests that genetic polymorphisms of LDLR are associated with PICH.
Subject(s)
Cerebral Hemorrhage/genetics , Genetic Predisposition to Disease , Polymorphism, Single Nucleotide/genetics , Receptors, LDL/metabolism , Adult , Aged , Cerebral Hemorrhage/diagnosis , Factor VIII/genetics , Female , Gene Frequency , Genetic Association Studies , Genotype , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Tomography Scanners, X-Ray ComputedABSTRACT
Cell sorting involves the segregation of two cell populations into `immiscible' adjacent tissues with smooth borders. Echinoid (Ed), a nectin ortholog, is an adherens junction protein in Drosophila, and cells mutant for ed sort out from the surrounding wild-type cells. However, it remains unknown which factors trigger cell sorting. Here, we dissect the sequence of this process and find that cell sorting occurs when differential expression of Ed triggers the assembly of actomyosin cable. Conversely, Ed-mediated cell sorting can be rescued by recruitment of Ed, via homophilic or heterophilic interactions, to the wild-type cell side of the clonal interface, even when differential Ed expression persists. We found, unexpectedly, that when actomyosin cable was largely absent, differential adhesion was sufficient to cause limited cell segregation but with a jagged tissue border (imperfect sorting). We propose that Ed-mediated cell sorting is driven both by differential Ed adhesion that induces cell segregation with a jagged border and by actomyosin cable assembly at the interface that smoothens this border.