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Early-phase amyloid PET reproduces metabolic signatures of cognitive decline in Parkinson's disease.Alzheimer's & Dementia (Amsterdam,... 2024Recent work suggests that amyloid beta (Aβ) positron emission tomography (PET) tracer uptake shortly after injection ("early phase") reflects brain metabolism and...
INTRODUCTION
Recent work suggests that amyloid beta (Aβ) positron emission tomography (PET) tracer uptake shortly after injection ("early phase") reflects brain metabolism and perfusion. We assessed this modality in a predominantly amyloid-negative neurodegenerative condition, Parkinson's disease (PD), and hypothesized that early-phase F-florbetaben (eFBB) uptake would reproduce characteristic hypometabolism and hypoperfusion patterns associated with cognitive decline in PD.
METHODS
One hundred fifteen PD patients across the spectrum of cognitive impairment underwent dual-phase Aβ PET, structural and arterial spin labeling (ASL) magnetic resonance imaging (MRI), and neuropsychological assessments. Multiple linear regression models compared eFBB uptake to cognitive performance and ASL MRI perfusion.
RESULTS
Reduced eFBB uptake was associated with cognitive performance in brain regions previously linked to hypometabolism-associated cognitive decline in PD, independent of amyloid status. Furthermore, eFBB uptake correlated with cerebral perfusion across widespread regions.
DISCUSSION
EFBB uptake is a potential surrogate measure for cerebral perfusion/metabolism. A dual-phase PET imaging approach may serve as a clinical tool for assessing cognitive impairment.
HIGHLIGHTS
Images taken at amyloid beta (Aβ) positron emission tomography tracer injection may reflect brain perfusion and metabolism.Parkinson's disease (PD) is a predominantly amyloid-negative condition.Early-phase florbetaben (eFBB) in PD was associated with cognitive performance.eFBB uptake reflects hypometabolism-related cognitive decline in PD.eFBB correlated with arterial spin labeling magnetic resonance imaging measured cerebral perfusion.eFBB distinguished dementia from normal cognition and mild cognitive impairment.Findings were independent of late-phase Aβ burden.Thus, eFBB may serve as a surrogate measure for brain metabolism/perfusion.
PubMed: 38912306
DOI: 10.1002/dad2.12601 -
The Indian Journal of Radiology &... Jul 2024: Despite documented correlation between glioma grades and dynamic contrast-enhanced (DCE) magnetic resonance (MR) perfusion-derived parameters, and its inherent...
Diagnostic Utility of Integration of Dynamic Contrast-Enhanced and Dynamic Susceptibility Contrast MR Perfusion Employing Split Bolus Technique in Differentiating High-Grade Glioma.
: Despite documented correlation between glioma grades and dynamic contrast-enhanced (DCE) magnetic resonance (MR) perfusion-derived parameters, and its inherent advantages over dynamic susceptibility contrast (DSC) perfusion, the former remains underutilized in clinical practice. Given the inherent spatial heterogeneity in high-grade diffuse glioma (HGG) and assessment of different perfusion parameters by DCE (extravascular extracellular space volume [Ve] and volume transfer constant in unit time [k-trans]) and DSC (rCBV), integration of the two into a protocol could provide a holistic assessment. Considering therapeutic and prognostic implications of differentiating WHO grade 3 from 4, we analyzed the two grades based on a combined DCE and DSC perfusion. : Perfusion sequences were performed on 3-T MR. Cumulative dose of 0.1 mmol/kg of gadodiamide, split into two equal boluses, was administered with an interval of 6 minutes between the DCE and DSC sequences. DCE data were analyzed utilizing commercially available GenIQ software. : Of the 41 cases of diffuse gliomas analyzed, 24 were WHO grade III and 17 grade IV gliomas (2016 WHO classification). To differentiate grade III and IV gliomas, Ve cut-off value of 0.178 provided the best combination of sensitivity (88.24%) and specificity (87.50%; AUC: 0.920; < 0.001). A relative cerebral blood volume (rCBV) of value 3.64 yielded a sensitivity of 70.59% and specificity of 62.50% ( = 0.018). The k-trans value, although higher in grade III than in grade IV gliomas, did not reach statistical significance ( = 0.108). : Uniqueness of employed combined perfusion technique, treatment naïve patients at imaging, user-friendly postprocessing software utilization, and ability of Ve and rCBV to differentiate between grade III and IV gliomas ( < 0.05) are the strengths of the present study, contributing to the existing literature and moving a step closer to achieving accurate MR perfusion-based glioma grading.
PubMed: 38912247
DOI: 10.1055/s-0043-1777742 -
The Indian Journal of Radiology &... Jul 2024Arterial spin labeling (ASL) perfusion imaging is widely used since its main advantage is that no intravenous contrast is needed. Given that perfusion is a crucial...
Arterial spin labeling (ASL) perfusion imaging is widely used since its main advantage is that no intravenous contrast is needed. Given that perfusion is a crucial biological characteristic for identifying tumor lesions, the qualitative noncontrast perfusion characteristics of these lesions were examined. We attempted utilizing the three-dimensional (3D) ASL technique to characterize skull base lesions and to highlight its crucial role in differentiating lesions. 3D ASL imaging of 20 patients with posterior skull base lesions was performed in a 3-T magnetic resonance (MR) system (Siemens Healthineers, Skyra, Erlangen, Germany). The common differential diagnoses of skull base lesions could be distinguished based on this qualitative evaluation. Glomus tumor has a strikingly increased perfusion when compared to meningiomas. The perfusion characteristics of metastasis depends on the primary tumor. Chondrosarcomas have a heterogeneously increased perfusion. Chordomas have variable perfusion, which helps in prognosticating the tumors. ASL benefits pediatric patients and in renal failure as well since it avoids the ethical ambiguity associated with contrast agents.
PubMed: 38912234
DOI: 10.1055/s-0044-1778727 -
Clinical Interventions in Aging 2024Postoperative cognitive dysfunction (POCD) is a neurological complication associated with surgery and anesthesia that is commonly observed in older patients, and it can... (Review)
Review
Postoperative cognitive dysfunction (POCD) is a neurological complication associated with surgery and anesthesia that is commonly observed in older patients, and it can significantly affect patient prognosis and survival. Therefore, predicting and preventing POCD is important. Regional cerebral oxygen saturation (rSO) reflects cerebral perfusion and oxygenation, and decreased intraoperative cerebral oxygen saturation has been reported to increase the risk of POCD. In this review, we elucidated the important relationship between the decline in rSO2 and risk of POCD in older patients. We also emphasized the importance of monitoring rSO2 during surgery to predict and prevent adverse perioperative cognitive outcomes. The findings reveal that incorporating intraoperative rSO2 monitoring into clinical practice has potential benefits, such as protecting cognitive function, reducing perioperative adverse outcomes, and ultimately improving the overall quality of life of older adults.
Topics: Humans; Postoperative Cognitive Complications; Aged; Cerebrovascular Circulation; Oxygen Saturation; Brain; Quality of Life; Oxygen; Cognitive Dysfunction
PubMed: 38911674
DOI: 10.2147/CIA.S462471 -
Plastic and Reconstructive Surgery.... Jun 2024Topical nitrates have demonstrated efficacy in improving flap perfusion. However, evidence for nontopical nitrates in modulation of flap perfusion dynamics has yet to be...
BACKGROUND
Topical nitrates have demonstrated efficacy in improving flap perfusion. However, evidence for nontopical nitrates in modulation of flap perfusion dynamics has yet to be consolidated. Here, we review evidence regarding the use of intravascular, sublingual, and oral nitrates in modulating flap perfusion.
METHODS
We performed a review of the literature for evidence linking nontopical nitrates and flap perfusion, and included clinical studies, animal studies, and in vitro studies.
RESULTS
Evidence suggests that intravascular, sublingual, and oral nitrates exert vasodilatory properties, which may be harnessed for identification of perforators and improved flap perfusion. We also found evidence suggesting nitrates may facilitate ischemic preconditioning while reducing ischemia-reperfusion injury.
CONCLUSIONS
Nitrates delivered intravascularly, sublingually, or orally may increase flap perfusion and serve as a method for ischemic preconditioning, particularly in the intraoperative setting.
PubMed: 38911578
DOI: 10.1097/GOX.0000000000005918 -
Cell Reports. Physical Science May 2024Recreating tissue environments with precise control over mechanical, biochemical, and cellular organization is essential for next-generation tissue models for drug...
Recreating tissue environments with precise control over mechanical, biochemical, and cellular organization is essential for next-generation tissue models for drug discovery, development studies, and the replication of disease environments. However, controlling these properties at cell-scale lengths remains challenging. Here, we report the development of printing approaches that leverage polyethylene glycol diacrylate (PEGDA) hydrogels containing photocaged oligonucleotides to spatially program material characteristics with non-destructive, non-ultraviolet light. We further integrate this system with a perfusion chamber to allow us to alter the composition of PEGDA hydrogels while retaining common light-activatable photocaged DNAs. We demonstrate that the hydrogels can capture DNA functionalized materials, including cells coated with complementary oligonucleotides with spatial control using biocompatible wavelengths. Overall, these materials open pathways to orthogonal capture of any DNA functionalized materials while not changing the sequences of the DNA.
PubMed: 38911357
DOI: 10.1016/j.xcrp.2024.101922 -
Frontiers in Physiology 2024This study was undertaken to explore the potential therapeutic effects of Tongyang Huoxue Granules (TYHX) on sinoatrial node (SAN) dysfunction, a cardiac disorder...
INTRODUCTION
This study was undertaken to explore the potential therapeutic effects of Tongyang Huoxue Granules (TYHX) on sinoatrial node (SAN) dysfunction, a cardiac disorder characterized by impaired impulse generation or conduction. The research question addressed whether TYHX could positively influence SAN ion channel function, specifically targeting the sodium-calcium exchanger ( ) and L-type calcium channel ( ) of the SAN.
METHODS
Sinoatrial node cells (SANCs) were isolated and cultured from neonatal Japanese big-eared white rabbits within 24 h of birth. The study encompassed five groups: Control, H/R (hypoxia/reoxygenation), H/R+100 μg/mL TYHX, H/R+200 μg/mL TYHX, and H/R+400 μg/mL TYHX. The H/R model, simulating hypoxia/reoxygenation stress, was induced within 5 days of culture. Whole-cell patch clamp technique was employed to record currents following a 3-min perfusion and stabilization period with TYHX.
RESULTS
TYHX administration demonstrated improvements in the ignition phase of impaired SANCs. The half-maximal effective dose of TYHX, as determined by SANC beating frequency, was found to be 323.63 μg/mL. Inward current density of increased in response to TYHX (200 and 400 μg/mL), while TYHX enhanced current density in H/R SANCs, with 400 μg/mL exhibiting greater efficacy. Additionally, TYHX regulated the gating mechanisms of by right-shifting the steady-state inactivation curve and accelerating recovery from inactivation. Notably, TYHX increased the activation time constant under 200 and 400 μg/mL, prolonged the fast inactivation time constant τ1 with 400 μg/mL, and extended the slow inactivation time constant τ2 with 100 and 400 μg/mL.
DISCUSSION AND CONCLUSION
The findings suggest that TYHX may hold promise as a therapeutic intervention for sinus node dysfunction, offering potential avenues for drug development aimed at safeguarding SAN function.
PubMed: 38911325
DOI: 10.3389/fphys.2024.1402478 -
Nature and Science of Sleep 2024Mental stress induced myocardial ischemia (MSIMI) is regarded as the primary cause of the angina with no obstructive coronary artery disease (ANOCA). Obstructive sleep...
PURPOSE
Mental stress induced myocardial ischemia (MSIMI) is regarded as the primary cause of the angina with no obstructive coronary artery disease (ANOCA). Obstructive sleep apnea (OSA) is autonomously linked to obstructive coronary heart disease, hypertension, and sudden cardiac death. Similar to the impact of psychological stress on the cardiovascular system, individuals with OSA experience periodic nocturnal hypoxia, resulting in the activation of systemic inflammation, oxidative stress, endothelial dysfunction, and sympathetic hyperactivity. The contribution of OSA to MSIMI in ANOCA patients is unclear. To explore the prevalence of OSA in ANOCA patients and the correlation between OSA and MSIMI, a prospective cohort of female ANOCA patients was recruited.
PATIENTS AND METHODS
We recruited female patients aged 18 to 75 years old with ANOCA and evaluated MSIMI using positron emission tomography-computed tomography. Subsequently, Level III portable monitors was performed to compare the relationship between OSA and MSIMI.
RESULTS
There is higher REI (7.8 vs 2.6, =0.019), ODI (4.7 vs 9.2, =0.028) and percentage of OSA (67.74% vs 33.33%, =0.004) in MSIMI patients. The patients diagnosed with OSA demonstrated higher myocardial perfusion imaging scores (SSS: 1.5 vs 3, = 0.005, SDS: 1 vs 3, P = 0.007). Adjusted covariates, the risk of developing MSIMI remained 3.6 times higher in OSA patients (β=1.226, OR = 3.408 (1.200-9.681), = 0.021).
CONCLUSION
Patients with MSIMI exhibit a greater prevalence of OSA. Furthermore, the myocardial blood flow perfusion in patients with OSA is reduced during mental stress.
PubMed: 38911317
DOI: 10.2147/NSS.S445219 -
Hepatobiliary Surgery and Nutrition Jun 2024
PubMed: 38911200
DOI: 10.21037/hbsn-24-144 -
Transplant International : Official... 2024Optimizing graft preservation is key for ex-situ split grafts in pediatric liver transplantation (PSLT). Hypothermic Oxygenated Perfusion (HOPE) improves... (Comparative Study)
Comparative Study
Optimizing graft preservation is key for ex-situ split grafts in pediatric liver transplantation (PSLT). Hypothermic Oxygenated Perfusion (HOPE) improves ischemia-reperfusion injury (IRI) and post-operative outcomes in adult LT. This study compares the use of HOPE in ex-situ partial grafts to static cold storage ex-situ partial grafts (SCS-Split) and to the gold standard living donor liver transplantation (LDLT). All consecutive HOPE-Split, SCS-Split and LDLT performed between 2018-2023 for pediatric recipients were included. Post-reperfusion syndrome (PRS, drop ≥30% in systolic arterial pressure) and reperfusion biopsies served as early indicators of IRI. We included 47 pediatric recipients (15 HOPE-Split, 17 SCS-Split, and 15 LDLT). In comparison to SCS-Split, HOPE-Split had a significantly shorter cold ischemia time (CIT) (470min vs. 538 min; =0.02), lower PRS rates (13.3% vs. 47.1%; = 0.04) and a lower IRI score (3 vs. 4; = 0.03). The overall IRI score (3 vs. 3; = 0.28) and PRS (13.3% vs. 13.3%; = 1) after HOPE-Split were comparable to LDLT, despite a longer CIT (470 min vs. 117 min; < 0.001). Surgical complications, one-year graft, and recipient survival did not differ among the groups. In conclusion, HOPE-Split mitigates early IRI in pediatric recipients in comparison to SCS-Split, approaching the gold standard of LDLT.
Topics: Humans; Liver Transplantation; Reperfusion Injury; Living Donors; Male; Female; Child; Child, Preschool; Organ Preservation; Perfusion; Adolescent; Infant; Cold Ischemia; Graft Survival; Retrospective Studies; Liver
PubMed: 38911062
DOI: 10.3389/ti.2024.12686