Application of Programmable Tetrahedral Framework Nucleic Acid-Based Nanomaterials in Neurological Disorders: Progress and Prospects

Tetrahedral framework nucleic acid (tFNA), a special DNA nanodevice, is widely applied in diverse biomedical fields. Due to its high programmability, biocompatibility, tissue permeability as well as its capacity for cell proliferation and differentiation, tFNA presents a powerful tool that could overcome potential barriers in the treatment of neurological disorders. This review evaluates recent studies on the use and progress of tFNA-based nanomaterials in neurological disorders.

Tissue Integrity and COVID-19

Tissue integrity depends on biological tissue stiffness. Tissue integrity can protect both against age-related diseases and against severity of COVID-19. The disruption of tight junctions and increase of tissue permeability with advancing age can be related with age-related diseases as well as with age-dependent COVID-19. Release of tightly bound water from collagen fibrils leads to the increase of extracellular matrix stiffness and to the associated with matrix stiffness increased tissue permeability. The link between arterial stiffness and oxidative stress has been reported and is expected to be studied in more detail in the future. Trehalose can be suggested for retardation of tightly bound water release and subsequent extracellular matrix crosslinking by advanced glycation end products. Increase in tissue permeability can be blocked by polyphenols that inhibit ICAM-1 expression and mitigate cytoskeleton reorganization. NF-κB activation as a result of increased stiffness and cytoskeleton reorganization can cause both cardiovascular pathologies and COVID-19. Increased cholesterol content in cell membrane leads to increased virus entry into cell and increase of cholesterol is linked with cardiovascular diseases. Statins and chitosan are known as cholesterol-lowering substances. Nrf2 inhibits NF-κB activation and NF-κB inhibits Nrf2 pathway.

Stimulated oxygen transport in tissue by magnetic needle acupuncture

AimTo understand physiology of magnetic needle acupuncture by investigating O2 transport in tissue during needle intervention.MethodsO2 transport in tissue is modeled by utilizing COMSOL with magnetic needle inserted into muscle tissue in a 2D porous media. The damaged tissue has been mimicked by an extracted tissue block with 1st order O2 consumption rate. The convection-diffusion O2 transport in the damaged tissue has been further evaluated by varying magnetic flux density B0 of the needle (0-1 T), myoglobin concentration (0-1 mM), O2 tension (5-100 Torr), O2 consumption rates, tissue permeability (10−12-10−6 m2) and porosity (0.1-0.9).Results1) Active O2 transport carried by interstitial flow is enhanced with the intervention of a magnetic needle by generating a high gradient magnetic field around the tip, which exerts a strong force (104 N/m3) on the diamagnetic interstitial fluid to accelerate the flow. 2) This interstitial flow can reach 30 μm/s at B0 = 1T and strongly correlates to the needle B0 and tissue permeability. 3) The needle stirs the interstitial flow can pump O2 flux by 1-2 orders of magnitude compared to that without magnetic field. 4) The enhancement of active O2 transport by magnetic needle is site-specific to the tissue in the vicinity of the tip. This enhancement is more effective in edema condition with a high tissue permeability (>10−9 m2).ConclusionsThe dramatic enhancement of O2 transport to restore the O2 mitochondria metabolism for dysfunctional muscle tissues is the fundamental physiological mechanism of magnetic needle acupuncture.

Employing CuInS2 quantum dots modified with vancomycin for detecting Staphylococcus aureus and iron(Ⅲ)

This paper describes a Near-infrared quantum dots (CuInS2 QDs)/antibiotics (vancomycin) nanoparticle-based assay for Staphylococcus aureus and iron(Ⅲ) detection. CuInS2 QDs with good biological tissue permeability and biocompatibility are combined with...

Microfluidic organ-on-a-chip model of the outer blood–retinal barrier with clinically relevant read-outs for tissue permeability and vascular structure

This organ-on-a-chip device of the outer blood retinal barrier will allow future studies of complex disease mechanisms and treatments of visual disorders using clinically relevant endpoints in vitro.

Assessment of tissue permeability by early CT perfusion as a surrogate parameter for early brain injury after subarachnoid hemorrhage

OBJECTIVEThe severity of early brain injury (EBI) after aneurysmal subarachnoid hemorrhage (aSAH) correlates with delayed cerebral ischemia (DCI) and outcome. A disruption of the blood-brain barrier is part of EBI pathophysiology. The aim of this study was to assess tissue permeability (PMB) by CT perfusion (CTP) in the acute phase after aSAH and its impact on DCI and outcome.METHODSCTP was performed on day 3 after aSAH. Qualitative and quantitative analyses of all CTP parameters, including PMB, were performed. The areas with increased PMB were documented. The value of an early PMB increase as a predictor of DCI and outcome according to the modified Rankin Scale (mRS) grade 3 to 24 months after aSAH was assessed. Possible associations of increased PMB with the Subarachnoid Hemorrhage Early Brain Edema Score (SEBES) and with early perfusion deficits, as radiographic EBI markers, were evaluated.RESULTSA total of 69 patients were enrolled in the study. An increased PMB on early CTP was detected in 10.1% (7/69) of all patients. A favorable outcome (mRS grade ≤ 2) occurred in 40.6% (28/69) of all patients. DCI was detected in 25% (17/69) of all patients. An increased PMB was a predictor of DCI (logistic regression, p = 0.03) but not of outcome (logistic regression, p = 0.40). The detection of increased PMB predicted DCI with a sensitivity of 25%, a specificity of 94%, a positive predictive value of 57%, and a negative predictive value of 79% (chi-square test p = 0.03). Early perfusion deficits were seen in 68.1% (47/69) of the patients, a finding that correlated with DCI (p = 0.005) but not with the outcome. No correlation was found between the SEBES and increased PMB.CONCLUSIONSChanges in PMB can be detected by early CTP after aSAH, which correlates with DCI. Future studies are needed to evaluate the time course of PMB changes and their interaction with therapeutic measures.