183 research outputs found
Effects of epidural compression on stellate neurons and thalamocortical afferent fibers in the rat primary somatosensory cortex
A number of neurological disorders such as epidural hematoma can cause compression of cerebral cortex. We here tested the hypothesis that sustained compression of primary somatosensory cortex may affect stellate neurons and thalamocortical afferent (TCA) fibers. A rat model with barrel cortex subjected to bead epidural compression was used. GolgiâCox staining analyses showed the shrinkage of dendritic arbors and the stripping of dendritic spines of stellate neurons for at least 3 months postâlesion. Anterograde tracing analyses exhibited a progressive decline of TCA fiber density in barrel field for 6 months postâlesion. Due to the abrupt decrease of TCA fiber density at 3 days after compression, we further used electron microscopy to investigate the ultrastructure of TCA fibers at this time. Some TCA fiber terminal profiles with dissolved or darkened mitochondria and fewer synaptic vesicles were distorted and broken. Furthermore, the disruption of mitochondria and myelin sheath was observed in some myelinated TCA fibers. In addition, expressions of oxidative markers 3ânitrotyrosine and 4âhydroxynonenal were elevated in barrel field postâlesion. Treatment of antioxidant ascorbic acid or apocynin was able to reverse the increase of oxidative stress and the decline of TCA fiber density, rather than the shrinkage of dendrites and the stripping of dendritic spines of stellate neurons postâlesion. Together, these results indicate that sustained epidural compression of primary somatosensory cortex affects the TCA fibers and the dendrites of stellate neurons for a prolonged period. In addition, oxidative stress is responsible for the reduction of TCA fiber density in barrels rather than the shrinkage of dendrites and the stripping of dendritic spines of stellate neurons
Different Renal Function Equations and Dosing of Direct Oral Anticoagulants in Atrial Fibrillation
BACKGROUND: Randomized trials of direct oral anticoagulants (DOACs) adopted the Cockcroft-Gault (CG) formula to calculate estimated glomerular filtration rate (eGFR) to determine the dosages of DOACs. OBJECTIVES: The authors aimed to investigate the agreements/disagreements of eGFRs calculated using different equations (CG, Modified Diet in Renal Disease [MDRD], and Chronic Kidney Disease Epidemiology Collaboration [CKD-EPI] formulas), and their impacts on the dosages of DOACs and clinical outcomes. METHODS: Medical data from a multicenter health care provider in Taiwan including 39,239 patients with atrial fibrillation were used. Among these patients, there were 11,185 and 2,323 patients treated with DOACs and warfarin, respectively. RESULTS: At the cutoff values of eGFR of 50 mL/min, the agreements were 78% between MDRD and CG and 81% between CKD-EPI and CG. The disagreements among the different equations were largely due to overestimations, especially for patients aged >75 years and with a body weight of <50 kg (58.8% for MDRD and 50.9% for CKD-EPI). Among patients receiving DOACs whose dosages were defined as âon labelâ based on MDRD or CKD-EPI, only those whose dosages were âtruly on labelâ based on CG were associated with a lower risk of major bleeding (adjusted HR: 0.34; 95% CI: 0.26-0.45) compared to warfarin. CONCLUSIONS: The adoptions of MDRD or CKD-EPI rather than CG would result in inappropriate dosing of DOACs (mainly overdosing), which would attenuate the advantages of DOACs compared to warfarin. The CG equation should be used as the gold standard to calculate eGFRs and guide the DOAC dosages
Association between use of nonâvitamin k oral anticoagulants with and without concurrent medications and risk of major bleeding in nonvalvular atrial fibrillation
Importance:Â Nonâvitamin K oral anticoagulants (NOACs) are commonly prescribed with other medications that share metabolic pathways that may increase major bleeding risk.
Objective:Â To assess the association between use of NOACs with and without concurrent medications and risk of major bleeding in patients with nonvalvular atrial fibrillation.
Design, Setting, and Participants: Retrospective cohort study using data from the Taiwan National Health Insurance database and including 91âŻ330 patients with nonvalvular atrial fibrillation who received at least 1 NOAC prescription of dabigatran, rivaroxaban, or apixaban from January 1, 2012, through December 31, 2016, with final follow-up on December 31, 2016.
Exposures:Â NOAC with or without concurrent use of atorvastatin; digoxin; verapamil; diltiazem; amiodarone; fluconazole; ketoconazole, itraconazole, voriconazole, or posaconazole; cyclosporine; erythromycin or clarithromycin; dronedarone; rifampin; or phenytoin.
Main Outcomes and Measures:Â Major bleeding, defined as hospitalization or emergency department visit with a primary diagnosis of intracranial hemorrhage or gastrointestinal, urogenital, or other bleeding. Adjusted incidence rate differences between person-quarters (exposure time for each person during each quarter of the calendar year) of NOAC with or without concurrent medications were estimated using Poisson regression and inverse probability of treatment weighting using the propensity score.
Results: Among 91âŻ330 patients with nonvalvular atrial fibrillation (mean age, 74.7 years [SD, 10.8]; men, 55.8%; NOAC exposure: dabigatran, 45âŻ347 patients; rivaroxaban, 54âŻ006 patients; and apixaban, 12âŻ886 patients), 4770 major bleeding events occurred during 447âŻ037 person-quarters with NOAC prescriptions. The most common medications co-prescribed with NOACs over all person-quarters were atorvastatin (27.6%), diltiazem (22.7%), digoxin (22.5%), and amiodarone (21.1%). Concurrent use of amiodarone, fluconazole, rifampin, and phenytoin with NOACs had a significant increase in adjusted incidence rates per 1000 person-years of major bleeding than NOACs alone: 38.09 for NOAC use alone vs 52.04 for amiodarone (difference, 13.94 [99% CI, 9.76-18.13]); 102.77 for NOAC use alone vs 241.92 for fluconazole (difference, 138.46 [99% CI, 80.96-195.97]); 65.66 for NOAC use alone vs 103.14 for rifampin (difference, 36.90 [99% CI, 1.59-72.22); and 56.07 for NOAC use alone vs 108.52 for phenytoin (difference, 52.31 [99% CI, 32.18-72.44]; Pâ<â.01 for all comparisons). Compared with NOAC use alone, the adjusted incidence rate for major bleeding was significantly lower for concurrent use of atorvastatin, digoxin, and erythromycin or clarithromycin and was not significantly different for concurrent use of verapamil; diltiazem; cyclosporine; ketoconazole, itraconazole, voriconazole, or posaconazole; and dronedarone.
Conclusions and Relevance:Â Among patients taking NOACs for nonvalvular atrial fibrillation, concurrent use of amiodarone, fluconazole, rifampin, and phenytoin compared with the use of NOACs alone, was associated with increased risk of major bleeding. Physicians prescribing NOAC medications should consider the potential risks associated with concomitant use of other drugs
Development of Interstitial Lung Disease Among Patients With Atrial Fibrillation Receiving Oral Anticoagulants in Taiwan.
ImportanceThere are emerging concerns from case reports and pharmacovigilance analyses of a possible risk of interstitial lung disease (ILD) associated with the use of factor Xa (FXa) inhibitors.ObjectiveTo evaluate the risk of incident ILD associated with the use of oral anticoagulants (OACs) in patients with nonvalvular atrial fibrillation (NVAF).Design, setting, and participantsThis nationwide retrospective cohort study used data from the Taiwan National Health Insurance Research Database. Patients with NVAF without preexisting lung disease who received OACs from June 1, 2012, to December 31, 2017, were included. Propensity score stabilized weighting (PSSW) was used to balance covariates across the medication groups (FXa inhibitors, dabigatran, and warfarin, with warfarin as the reference). Patients were followed up from the drug index date until the onset of ILD, death, or end of the study (December 31, 2019), whichever occurred first. Data were analyzed from September 11, 2021, to August 3, 2022.ExposuresPatients with NVAF were treated with FXa inhibitors, dabigatran, or warfarin.Main outcomes and measuresNew-onset idiopathic ILD.ResultsAmong the 106âŻ044 patients (mean [SD] age, 73.4 [11.9] years; 59 995 men [56.6%]) included in the study, 64âŻ555 (60.9%) received FXa inhibitors (apixban [nâ=â15âŻ386], edoxaban [nâ=â12âŻ413], and rivaroxaban [nâ=â36âŻ756]), 22âŻ501 (21.2%) received dabigatran, and 18âŻ988 (17.9%) received warfarin at baseline. The FXa inhibitors were associated with a higher risk of incident ILD (0.29 vs 0.17 per 100 patient-years; hazard ratio, 1.54 [95% CI, 1.22-1.94]; PâConclusions and relevanceResults of this study suggest that FXa inhibitors were associated with lung injury among patients with NVAF who were treated with OACs. Physicians should be vigilant in monitoring for any potential adverse lung outcomes associated with the use of these drugs
Off-label dosing of non-vitamin K antagonist oral anticoagulants and clinical outcomes in Asian patients with atrial fibrillation
Direct Oral Anticoagulants in Atrial Fibrillation Patients With Concomitant Hyperthyroidism
Objective
Patients with hyperthyroidism were excluded from randomized clinical trials of direct oral anticoagulants(DOACs) for stroke prevention in patients with non-valvular atrial fibrillation (NVAF).
Methods
We performed a nationwide retrospective cohort study using data from the Taiwan National Health Insurance Research Database. We enrolled 3,213 and 1,181 NVAF patients with hyperthyroidism taking DOACs and warfarin, respectively, from June 1, 2012 to December 31, 2017. We also enrolled 53,591 and 16,564 NVAF patients without hyperthyroidism taking DOACs and warfarin, respectively. We used propensity score-based stabilized weights (PSSWs) to balance covariates across the study groups. We also used 1:4 matching on both taking DOACs, with (n=3,213) and without hyperthyroidism (n=12,852); and both taking warfarin, with (n=1,181) and without hyperthyroidism (n=4,724).
Results
After PSSW, DOAC had a comparable risk of ischemic stroke/systemic embolism (IS/SE) and a lower risk of major bleeding (hazard ratio (HR):0.65; [95% confidential interval (CI):0.44-0.96]; P=0.0295) than warfarin among patients with hyperthyroidism. There were comparable risks of IS/SE and major bleeding between those patients with and without hyperthyroidism. However, patients taking warfarin with hyperthyroidism had a lower risk of IS/SE than those without hyperthyroidism (HR:0.61; [95%CI:0.43-0.86]; P=0.0050).
Conclusion
Among NVAF Asian patients with concomitant hyperthyroidism, DOACs may be an effective and safer alternative to warfarin. Thromboprophylaxis with DOACs may be considered for such patients, and it is important to validate this finding in further prospective study.Supplemental materials (figures and tables) for the article of "Direct Oral Anticoagulants in Atrial Fibrillation Patients with Concomitant Hyperthyroidism"
Funding provided by: Chang Gung Memorial HospitalCrossref Funder Registry ID: http://dx.doi.org/10.13039/100012553Award Number: CMRPG3G1371-3Funding provided by: Chang Gung Memorial HospitalCrossref Funder Registry ID: http://dx.doi.org/10.13039/100012553Award Number: CMRPG3F0991-3Funding provided by: Chang Gung Memorial HospitalCrossref Funder Registry ID: http://dx.doi.org/10.13039/100012553Award Number: CMRPD1K0031Funding provided by: Chang Gung Memorial HospitalCrossref Funder Registry ID: http://dx.doi.org/10.13039/100012553Award Number: CMRPG3K0021We performed a nationwide retrospective cohort study using data from the Taiwan National Health Insurance Research Database. We enrolled 3,213 and 1,181 NVAF patients with hyperthyroidism taking DOACs and warfarin, respectively, from June 1, 2012 to December 31, 2017
The risk of incident atrial fibrillation in patients with type 2 diabetes treated with sodium glucose cotransporter-2 inhibitors, glucagon-like peptide-1 receptor agonists, and dipeptidyl peptidase-4 inhibitors: a nationwide cohort study.
BackgroundAlthough a few meta-analyses were conducted to compare the risk of incident atrial fibrillation (AF) between sodium-glucose cotransporter-2 inhibitor (SGLT2i), glucagon-like peptide-1 receptor agonists (GLP-1RA), and other anti-hyperglycemic agents using indirect or direct comparison, the above analyses showed conflicting results with each other. We aimed to evaluate the risk of new-onset AF associated with the use of SGLT2i, GLP-1RA, and dipeptidyl peptidase-4 inhibitor (DPP4i) among a large longitudinal cohort of diabetic patients.MethodsIn this nationwide retrospective cohort study based on the Taiwan National Health Insurance Research Database, a total of 344,893, 44,370, and 393,100 consecutive patients with type 2 diabetes without preexisting AF receiving GLP-1RA, SGLT2i, and DPP4i, respectively, were enrolled from May 1, 2016, to December 31, 2019. We used 1:1 propensity score matching (PSM) to balance covariates across paired study groups. Patients were followed from the drug index date until the occurrence of AF, death, discontinuation of the index drug, or the end of the study period (December 31, 2020), whichever occurred first.ResultsAfter PSM, there were 245,442, 43,682, and 39,190 paired cohorts of SGLT2i-DPP4i, SGLT2i-GLP-1RA, and GLP-1RA-DPP4i, respectively. SGLT2i treatment was associated with lower risk of new-onset AF in participants with type 2 diabetes compared with either DPP4i [hazard ratio (HR):0.90; 95% confidential interval (CI) 0.84-0.96; Pâ=â0.0028] or GLP-1RA [HR 0.74; 95% CI 0.63-0.88; Pâ=â0.0007] treatment after PSM. There was no difference in the risk of incident AF between GLP-1RA and DPP4i users [HR 1.01; 95% CI 0.86-1.19; Pâ=â0.8980]. The above findings persisted among several important subgroups. Dapagliflozin was specifically associated with a lower risk of new-onset AF compared with DPP4i (P interactionâ=â0.02).ConclusionsCompared with DPP4i, SGLT2i but not GLP-1RA was associated with a lower risk of incident AF in patients with type 2 diabetes
A 9âbp cis-element in the promoters of class I small heat shock protein genes on chromosome 3 in rice mediates L-azetidine-2-carboxylic acid and heat shock responses
In rice, the class I small heat shock protein (sHSP-CI) genes were found to be selectively induced by L-azetidine-2-carboxylic acid (AZC) on chromosome 3 but not chromosome 1. Here it is shown that a novel cis-responsive element contributed to the differential regulation. By serial deletion and computational analysis, a 9âbp putative AZC-responsive element (AZRE), GTCCTGGAC, located between nucleotides â186 and â178 relative to the transcription initiation site of Oshsp17.3 was revealed. Deletion of this putative AZRE from the promoter abolished its ability to be induced by AZC. Moreover, electrophoretic mobility shift assay (EMSA) revealed that the AZRE interacted specifically with nuclear proteins from AZC-treated rice seedlings. Two AZREâprotein complexes were detected by EMSA, one of which could be competed out by a canonical heat shock element (HSE). Deletion of the AZRE also affected the HS response. Furthermore, transient co-expression of the heat shock factor OsHsfA4b with the AZRE in the promoter of Oshsp17.3 was effective. The requirement for the putative AZRE for AZC and HS responses in transgenic Arabidopsis was also shown. Thus, AZRE represents an alternative form of heat HSE, and its interaction with canonical HSEs through heat shock factors may be required to respond to HS and AZC
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