Focused ultrasound (FUS) in combination with microbubbles temporally and locally increases the permeability of the blood-brain barrier (BBB) for facilitating drug delivery. However, the temporary effects of FUS on the brain microstructure and microcirculation need to be addressed. We used label-free optical coherence tomography (OCT) and OCT angiography (OCTA) to investigate the morphological and microcirculation changes in mouse brains due to FUS exposure at different power levels. Additionally, the recovery progress of the induced effects was studied. The results show that FUS exposure causes cerebral vessel dilation and can be identified and quantitatively analyzed via OCT/OCTA. Micro-hemorrhages can be detected when an excessive FUS exposure power is applied, causing the degradation of OCTA signal owing to strong scattering by leaked red blood cells (RBCs) and weaker backscattered intensity from RBCs in vessels. The vessel dilation effect due to FUS exposure was found to abate in several hours. This study demonstrates that the FUS-induced cerebral transiently dilated effects can be differentiated and monitored with OCTA, and shows the feasibility of using OCT/OCTA as a novel tool for long-time monitoring of cerebral vascular dynamics during FUS-BBB opening process.
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http://dx.doi.org/10.1364/BOE.9.000507 | DOI Listing |
Obstet Gynecol
December 2024
Department of Obstetrics and Gynecology, The Ohio State University, Columbus, Ohio; the Department of Obstetrics and Gynecology, Brown University, Providence, Rhode Island; and the Department of Preventive Medicine and the Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois.
We examined the association between blood pressure (BP) in the early third trimester and hypertension 10-14 years after delivery per American College of Cardiology and American Heart Association recommendations. We conducted a secondary analysis using the prospective HAPO FUS (Hyperglycemia and Adverse Pregnancy Outcome Follow-up Study) in patients without a chronic hypertension diagnosis. The exposure and outcome were systolic and diastolic BP measured in the early third trimester and 10-14 years after delivery, respectively.
View Article and Find Full Text PDFBrain Stimul
December 2024
Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada.
Background: Current strategies for reducing blood pressure (BP) are ineffective and unsafe for many patient populations, including drug-resistant hypertension and during pregnancy. Stimulating the periaqueductal grey (PAG) region has shown promise in treating drug-resistant hypertension in patients using deep brain stimulation.
Objective: To develop a minimally invasive neuromodulation technique for the sustained treatment of hypertension.
Bioinform Biol Insights
November 2024
Federal Research Center of Fundamental and Translational Medicine, Laboratory of molecular mechanisms of carcinogenesis, Novosibirsk, Russia.
MicroRNAs play a significant role in the development of cancers, including lung cancer. A recent study revealed that smoking, a key risk factor for lung cancer, increased the levels of hsa-mir-301a in the tumor tissues of patients with lung squamous cell carcinoma (LUSC). The aim of the current study is to investigate the mechanism by which tobacco smoke increases hsa-mir-301a levels in LUSC tumor tissues using bioinformatics analysis.
View Article and Find Full Text PDFHum Gene Ther
December 2024
Department Mental Retardation & Birth Defect Research, National Center of Neurology & Psychiatry, National Institute of Neuroscience, Tokyo, Japan.
Systemic delivery of adeno-associated virus (AAV) vectors targeting the central nervous system has the potential to solve many neurodevelopmental disorders, yet it is made difficult by the filtering effect of the blood-brain barrier and systemic complications. To overcome this limitation, we attempted to inject a Venus-expressing, oligodendrocyte-selective AAV9 viral vector in the ventricles together with lipid microbubbles and subjected them to focused ultrasound (FUS); the resulting mechanical stimulation on the brain ventricles is able to open small, temporary gaps from which vector particles can leak and spread. Our findings indicate that FUS can increase viral vector diffusion across both the anteroposterior and left-right axes without influencing cell tropism; significant effects were found with 60 and 90 s exposure time, but no effects were observed with longer intervals.
View Article and Find Full Text PDFMutat Res Rev Mutat Res
December 2024
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