Posted at 10.06.2018
Echogenic bubble formulations have vast applications disease analysis and remedy. Therefore, nanobubbles were ready and the contrast agent function was evaluated in order to study the nanosized bubble's property for ultrasonic imaging. For this purpose Coumarin-6 as a model medicine was loaded into nanobubbles to research the medication delivery potential to skin cells. The results revealed that the nanobubbles made up of 1% of Tween 80, and 3 mg/ml of lipid proved helpful well as an ultrasonic contrast agent by showing a contrast result in the liver region in vivo. The drug-loaded nanobubbles could enhance medication delivery to skin cells significantly, and the procedure was examined by sigmoidally fitted the pharmacokinetic curve. It can be concluded that the nanobubble formulation is a promising approach for both ultrasound imaging and drug delivery enhancing.
The capacity of oxygen-loaded chitosan bubbles to switch air in the presence or in the lack of Ultrasound is researched. Results shows that Air delivery is increased by sonication and both occurrence and time duration of Ultrasound damaged the exchange kinetics.
Nanobubbles with measured measurements of 30 nm extensive and 1 nm high on a hydrophobic Au (111) surface in air-saturated drinking water can be viewed using tapping mode atomic pressure microscopy with a Q-control system. The existence of the nanobubbles implies that smaller, unstable ones may be there about the same expanded hydrophobic surface or in drinking water confined to hydrophobic pores on the nanometer level. This leads to propose an idea that a direct obstruction of the pore of an ligand-gated ion channel can occur from the deposition of anaesthetic molecules at a gating region with a relatively large hydrophobic inner surface in the pore.
From the point of view of basic safety, non-viral vector systems signify a good gene delivery system for gene therapy. However, the transfection efficiency of non-viral vectors in vivo is normally very low. Microbubbles, used as imaging brokers for diagnostic echocardiography, could promote gene delivery into skin cells when coupled with ultrasound exposure. Research workers therefore developed novel liposomal bubbles (Bubble liposomes) made up of the lipid nanobubbles of perfluoropropane which can be used as ultrasound imaging agent. These Bubble liposomes were smaller in diameter than normal microbubbles and induced cavitation after exposure to ultrasound. These results recommended that cavitation of these Bubble liposomes could be a competent approach for delivering plasmid DNA into skin cells. In addition, in in vivo gene delivery, the mixture of Bubble liposomes and ultrasound provided more effective gene delivery than standard lipofection methods, further suggesting that Bubble liposomes could succeed as a non-viral vector system in in vivo gene delivery.
Bubble liposomes (liposomes which entrap an ultrasound imaging gas) may constitute a distinctive system for delivering various molecules effectively into mammalian skin cells in vitro. On this study, Bubble liposomes were compared with cationic lipid (CL)-DNA complexes as potential gene delivery service providers into tumor in vivo. The delivery of genes by Bubble liposomes depended on the strength of the applied ultrasound. Transfection efficiency plateaued at 0. 7 W/cm2 ultrasound strength. Bubble liposomes proficiently transferred genes into cultured skin cells even when the skin cells were exposed to ultrasound for only one 1 s. In addition, Bubble liposomes could create the luciferase gene more effectively than CLDNA complexes into mouse ascites tumor skin cells and sound tumor tissues. This research conclude that the combination of Bubble liposomes and ultrasound is a minimally-invasive and tumor specific gene transfer method in vivo.
In dendritic cell (DC)-based mostly cancer immunotherapy, it's important that DCs present peptides produced from tumor-associated antigens on MHC course I, and activate tumor-specific cytotoxic T lymphocytes (CTLs). However, MHC school I generally present endogenous antigens indicated in the cytosol. Therefore one impressive approach with the capacity of directly delivering exogenous antigens in to the cytosol of DCs; i. e. , a MHC school I-presenting pathway is developed. In this study, the effect of antigen delivery using perfluoropropane gas-entrapping liposomes (Bubble liposomes, BLs) and ultrasound coverage on MHC school I presentation levels in DCs, as well as the feasibility of applying this antigen delivery system in DC-based tumor immunotherapy is investigated. DCs were treated with ovalbumin (OVA) as a model antigen, BLs and Ultrasound visibility. OVA was directly delivered into the cytosol but not via the endocytosis pathway, and OVA-derived peptides were shown on MHC category I. This end result implies that exogenous antigens can be named endogenous antigens when provided into the cytosol. Immunization with DCs treated with OVA, BLs and Ultrasoand subjection proficiently induced OVA-specific CTLs and led to the complete rejection of E. G7-OVA tumors. These data indicate that the mixture of BLs and Ultrasound coverage is a appealing antigen delivery system in DC-based tumor immunotherapy.
Interleukin-12 (IL-12) gene remedy is likely to succeed against cancers since it primes the disease fighting capability for cancer cells. In this therapy, it is important to generate IL-12 gene appearance in the tumor cells. Sonoporation is an attractive technique for growing non-invasive and non-viral gene delivery systems, but simple sonoporation using only ultrasound is not an effective cancer gene remedy due to low efficiency of gene delivery. Researchers solve this problem by merging ultrasound and novel ultrasoundsensitive liposomes (Bubble liposomes) that have the ultrasound imaging gas perfluoropropane, this is an efficient gene delivery system, which Bubble liposome collapse (cavitation) is induced by ultrasound visibility. In this research, they evaluated the utility of this system in cancers gene remedy using IL-12 corded plasmid DNA. The combination of Bubble liposomes and ultrasound significantly suppressed tumor progress. This therapeutic impact was T-cell based mostly, requiring mainly Disc8+ T lymphocytes in the effector period, as confirmed by the mouse in vivo depletion assay. Furthermore, migration of Disc8+ T skin cells was observed in the mice, indicating that the combo of Bubble liposomes and ultrasound is an excellent non-viral vector system in IL-12 cancer tumor gene remedy.
Nanobubbles has combine properties of polymeric drug companies, ultrasound imaging comparison agencies, and enhancers of ultrasound-mediated medicine delivery has been developed. At room temperatures, perfluorocarbon nanodroplets stabilized by the walls manufactured from biodegradable block copolymers. Upon heat to physiological temperatures, the nanodroplets convert into nano/microbubbles. The phase condition of the systems and bubble size may be controlled by the copolymer/ perfluorocarbon quantity percentage. Upon intravenous shots, a long-lasting, strong and selective ultrasound distinction is observed in the tumor volume indicating nanobubble extravasation through the defective tumor microvasculature, suggesting their coalescence into much larger, highly echogenic microbubbles in the tumor muscle. Beneath the action of tumor-directed ultrasound, microbubbles cavitate and collapse resulting in a release of the encapsulated medication and dramatically increased intracellular drug uptake by the tumor skin cells. This result is tumor-selective; no accumulation of echogenic microbubbles is seen in other organs. Effective chemotherapy of the MDA MB231 breasts cancer tumor tumors has been achieved using this technique.
In the treating acute ischemic stroke recanalization is the key goal. Thrombolysis with recombinant muscle plasminogen activator (rtPA) is useful in humans, but shows significant problems including poor and incomplete recanalization and consistent bleeding issues. Limited therapeutic windowpane (the first three time after starting point) is the major limitation leading to reach too little patients. Therefore, adjunctive remedies increasing the reperfusion time windowpane, increasing effectiveness and minimizing side effects of rtPA are needed. Ultrasound augmentation of rtPA-mediated thrombolysis is recommended to overcome many of these problems, but low-frequency ultrasound (significantly less than 1 MHz) is not safe and high frequency ultrasound (2 MHz) is very little effective. Researchers suggest that normobaric hyperoxia (NBO) may increase the efficiency of ultrasound and rtPA combination in addition to its efficacy in acute ischemic stroke. Briefly, NBO improves arterial partial air pressure (pO2) significantly up to 6-flip. Increase of pO2 results within an increase of dissolved air in the blood corresponding to Henry's laws. Enhanced dissolved oxygen boosts gas nuclei creation around and within the clot, and reduces the Blake threshold. Under ultrasound field, these small gas nuclei form nanobubbles which fuel inertial cavitation as substrates, and for that reason improve the clot fragmentation and lysis. This hypothesis is not tested up to now. The combo of rtPA, restorative ultrasound and NBO may become more efficacious than rtPA exclusively or its combination with ultrasound as acute stroke treatment modality, because each has different and probably additive mechanism of action.
A new approach to optically guided handled release was experimentally evaluated with liposomes filled with a molecular insert and yellow metal nanoparticles (NPs). NPs were subjected to short laser beam pulses to cause transient vapor bubbles throughout the NPs, plasmonic nanobubbles, in order to disrupt the liposome and eject its molecular contents. The release effectiveness was tuned by differing the life span and size of the nanobubble with the fluence of the laser beam pulse. Optical scattering by nanobubbles correlated to the molecular release and was used to guide the release. The release of two fluorescent proteins from specific liposomes has been straight monitored by fluorescence microscopy, while the era of the plasmonic nanobubbles was imaged and measured with optical scattering techniques. Plasmonic nanobubble-induced release was found to be always a mechanical, nonthermal process that will require a single laser pulse and ejects the liposome details inside a millisecond timescale without damage to the molecular cargo and that may be controlled through the fluence of laser beam pulse.
Dextran nanobubbles were well prepared with a dextran shell and a perfluoropentan central in which air was stored. To improve the steadiness polyvinylpirrolidonewas also added to the formulation as stabilizing agent. Rhodamine B was used as fluorescent marker to obtain fluorescent nanobubbles. The nanobubble formulations exhibited sizes around 500 nm, a negative surface demand and a good capacity of loading air, no hemolytic activity or toxic influence on cell lines. The fluorescent labelled nanobubbles could be internalized in Vero skin cells. Oxygen-filled nanobubbles were able to release oxygen in various hypoxic alternatives at different time after their preparation in in vitro tests. The air release kinetics could be increased after nanobubble insonation with ultrasound at 2. 5 MHz. The oxygen-filled nanobubble formulations might be suggested for healing applications in a variety of diseases.
When targeted, Rhodamine-labeled echogenic liposomes (Rh- ELIP) including nanobubbles are delivered to the arterial wall structure, and whether 1 MHz continuous wave ultrasound is given, it improve the delivery account of the medicine. Aortae excised from apolipoprotein-E deficient (n=8) and wild-type (n=8) mice were attached in a pulsatile flow system by which Rh-ELIP were supplied in a stream of bovine serum albumin. Fifty percent the aortae from each group were treated with 1-MHz ongoing wave ultrasound at 0. 49 MPa peak-to-peak pressure, and half underwent sham vulnerability. Ultrasound guidelines were chosen to market stable cavitation and prevent inertial cavitation. A broadband hydrophone was used to monitor cavitation activity. After treatment, aortic areas were ready for histology and examined by an individual blinded to treatment conditions. Delivery of Rh-ELIP to the vascular endothelium was noticed, and sub-endothelial penetration of Rh-ELIP was within five of five ultrasound-treated aortae and was absent in those not subjected to ultrasound. However, the degree of penetration in the ultrasound-exposed aortae was adjustable. There is no proof ultrasound-mediated injury in virtually any specimen. Ultrasound-enhanced delivery within the arterial wall membrane was exhibited in this book model, that allows quantitative analysis of healing delivery.
The arrival of microbubble comparison agents has increased the capacities of ultrasound as a medical imaging modality and stimulated innovative approaches for ultrasound-mediated medication and gene delivery. To improve their multifunctional comparison and delivery capacity, it is critical to reduce bubble size to the nanometer range without reducing echogenicity, this is achieved by using the surfactant Pluronic, a triblock copolymer of ethylene oxide copropylene oxide coethylene oxide into the formulation. Five Pluronics (L31, L61, L81, L64 and P85) with a variety of molecular weights (Mw: 1100 to 4600 Da) were designed into the lipid shell either before or after lipid film hydration and before addition of perfluorocarbon gas. Results show that PluronicЛ†'lipid relationships lead to a significantly reduced bubble size. One of the tested formulations, bubbles made out of Pluronic L61 were the tiniest with a mean hydrodynamic diameter of 207. 9 ± 74. 7 nm set alongside the 880. 9 ± 127. 6 nm control bubbles. Pluronic L81 also significantly reduced bubble size to 406. 8 ± 21. 0 nm. We conclude that Pluronic is effective in lipid bubble size control, and Pluronic Mw, hydrophilicЛ†'lipophilic balance (HLB), and Pluronic/lipid ratio are critical determinants of the bubble size. The results have shown that although bubbles are nanosized, their stableness and in vitro and in vivo echogenicity are not compromised. The ensuing nanobubbles may be better fitted to contrast increased tumor imaging and succeeding healing delivery.
To fabricate the nanobubble-based distinction agent, the researchers first ultrasonicate a mixture of Period 60 and polyoxyethylene 40 stearate and then use differential centrifugation to isolate the relevant subpopulation from the father or mother suspensions.
Excellent vitality Doppler development was found in vivo in renal imaging pursuing intravenous injection of the team's nanobubble contrast agent. The very small bubbles are small enough to leak through the vascular pores of the tumour and accumulate in the tumour muscle through passive targeting because of the higher permeability of tumour blood vessels weighed against normal muscle vasculature. After extravasations, an elevated acoustic indication is from the gathered nanobubbles, providing strong ultrasound compare imaging.
In addition to diagnostic applications, the nanobubbles show great potential as ultrasound-mediated drug-delivery vehicles to help medication release and extravascular delivery.
Nanobubbles (NB) with ultrasound (US) to permeabilize cancer tumor skin cells and potentiate the cytotoxicity of anti-cancer drugs (cisplatin and 5-FU). Analysts used 293T human kidney, MCF7 human being breast adenocarcinoma, EMT6 murine mammary carcinoma and digestive tract 26 murine rectum carcinoma cells. Cytotoxicity was assessed with MTT assay. Under optimal conditions, NB (albumin or lipid, 10% v/v) combined with US (regularity: 945 kHz, obligation percentage: 20-80%, pressure: 0. 96 MPa) produced significant cytotoxicity not seen with either US or medicine alone. Increasing the duty proportion up to 80% further increased cytotoxicity. In the observation of fast collapse of nanobubbles around, we hypothesised that sub-nanobubbles (cavitation bubbles) are produced by the collapse of nanobubbles and distress waves made from the cavitation bubbles lead to the transient membrane permeability, accompanied by admittance of plasmid DNA or drugs. To investigate the mechanisms of molecular delivery with surprise waves, we performed molecular dynamics (MD) simulations of the discussion of the distress influx impulse with a lipid bilayer and consequently increased the fluidity of every molecule of the level. These changes in bilayer may make a difference factors to enhance drug susceptibility of cancers cells.
Novel biocompatible nanobubbles were fabricated by ultrasonication of a mixture of Span 60 and polyoxyethylene 40 stearate (PEG40S) accompanied by differential centrifugation to isolate the relevant subpopulation from the father or mother suspensions. Particle sizing research and optical microscopy inspection suggested that the newly generated micro/nanobubble suspension was polydisperse and the size circulation was bimodal with large amounts of nanobubbles. To develop a nano-sized distinction agent that is small enough to leak through tumor pores, a fractionation to extract smaller bubbles by variant in the time of centrifugation at 20g (comparative centrifuge field, RCF) was advised. The results proved that the populace of nanobubbles with a exactly handled mean diameter could be sorted from the initial polydisperse suspensions to meet up with the given requirements. The isolated bubbles were steady over fourteen days under the coverage of perfluoropropane gas. The acoustic habit of the nano-sized comparison agent was evaluated using electric power Doppler imaging in a normal rabbit model. A fantastic power Doppler advancement was found in vivo renal imaging after intravenous injection of the obtained nanobubbles. Given the wide-ranging spectral range of potential scientific applications, the nano-sized comparison agent might provide a adaptable adjunct for ultrasonic imaging enhancement and/or treatment of tumors.
Functionalised nanoparticles have been suggested as potential providers for non-invasive treatments where an exterior source like a laser or an electro-magnetic wave is utilized to warm up targeted allergens for either medicine release or malignant cell damage. It is suitable to obtain intracellular reactions to minimise the damage to health cells. However, it is still debatable from the thermal response perspective, whether intracellular hyperthermia is better than extracellular delivery anticipated to standard ideas of localisation of warmth by nanoparticles. This work conducts an analytical study on the heating system of a single nanoparticle by way of a pulsed laser and reveals the potential role of the forming of nanobubbles around heated up particles. The quick creation and contraction of bubbles around heated nanoparticles, from the propagation of pressure waves, could bring thermal-mechanical damage to surrounding skin cells at a dimension much bigger than that of a nanoparticle.
Apomorphine is a dopamine receptor agonist for treating Parkinson's disease. However, its professional medical application is bound by its instability and the necessity for frequent injections. The aim of today's work was to build up acoustically lively perfluorocarbon nanobubbles (PNs) for encapsulation of both apomorphine HCl and base forms to circumvent these delivery problems. The PNs were ready using coconut oil and perfluoropentane as the inner phase, which was emulsified by phospholipids and cholesterol. The morphology, size, zeta probable, and medication release of the PNs were characterized. The particle size ranged from 150 to 380 nm, with differences in the oil or perfluorocarbon percentage in the formulations. Atomic force microscopy validated oval- or raisin-shaped particles and a thin size distribution of the systems (polydispersity index = 0. 25-0. 28). The stability experimental results indicated that PNs could protect apomorphine from degradation. Evaporation of the PNs at 37 levels C was also limited. Apomorphine HCl and platform in PNs demonstrated retarded and sustained release information. Ultrasound imaging established the echogenic activity of PNs developed in this study. The apomorphine HCl release by insonation at 1 MHz proved enhancements of two- to fourfold compared to the non-ultrasound group, illustrating a possible drug-targeting impact. On the contrary, apomorphine base confirmed a decreased release account with ultrasound application. Apomorphine-loaded PNs proved promising stableness and safety. These were successful in sustaining apomorphine delivery.
Drug delivery in polymeric micelles combined with tumor irradiation by ultrasound leads to effective drug focusing on, but this system requires previous tumor imaging. A technology that merged ultrasound imaging with ultrasound-mediated nanoparticle-based targeted chemotherapy could therefore have important applications in cancers treatment. Mixtures of drug-loaded polymeric micelles and perfluoropentane (PFP) nano/microbubbles stabilized by the same biodegradable block copolymer were ready. Size distribution of nanoparticles was assessed by powerful light scattering. Cavitation activity (oscillation, development, and collapse of microbubbles) under ultrasound was evaluated predicated on the changes in micelle/microbubble volume ratios. The result of the nano/microbubbles on the ultrasound-mediated mobile uptake of doxorubicin (Dox) in MDA MB231 breasts tumors in vitro and in vivo (in mice bearing xenograft tumors) was determined by movement cytometry. Statistical assessments were two-sided. Phase condition and nanoparticle sizes were very sensitive to the copolymer/perfluorocarbon quantity ratio. At physiologic temperature, nanodroplets changed into nano/microbubbles. Doxorubicin was localized in the microbubble walls shaped by the block copolymer. Upon intravenous injection into mice, Dox-loaded micelles and nanobubbles extravasated selectively in to the tumor interstitium, where in fact the nanobubbles coalesced to produce microbubbles with a strong, durable ultrasound distinction. Doxorubicin was strongly maintained in the microbubbles but released in response to therapeutic ultrasound. Microbubbles cavitated under the action of tumor-directed ultrasound, which improved intracellular Dox uptake by tumor cells in vitro to a statistically significant magnitude in accordance with that witnessed with unsonicated microbubbles (medicine uptake proportion = 4. 60; 95% confidence period [CI] = 1. 70 to 12. 47; P =. 017) and unsonicated micelles (medicine uptake ratio = 7. 97; 95% CI = 3. 72 to 17. 08; P =. 0032) and resulted in tumor regression in the mouse model. Multifunctional nanoparticles that are tumor-targeted medicine service providers, long-lasting ultrasound compare agents, and enhancers of ultrasound-mediated medicine delivery have been developed and are worthy of further exploration as tumors therapeutics.
Recently, there have been numerous information on the use of non-thermal ultrasound energy for dealing with various diseases in mixture with drugs. Furthermore, the intro of microbubbles and nanobubbles as providers/enhancers of drugs has added a complete new dimension to therapeutic ultrasound. Non-thermal mechanisms for effects seen include various kinds of energy credited to cavitation, acoustic streaming, micro jets and radiation push which increases alternatives for targeting muscle with drugs, enhancing drug performance or even chemically activating certain materials. Examples such as development of thrombolytic agents by ultrasound are actually beneficial for severe stroke patients and peripheral arterial occlusions. Non-invasive low level focused ultrasound in conjunction with anti-cancer drugs may help to lessen tumor size and decrease recurrence while minimizing severe drug part effects. Substance activation of drugs by ultrasound energy for treatment of atherosclerosis and tumors is another new field recently referred to as "Sonodynamic therapy". Lastly, innovations in molecular imaging have aroused great targets in making use of ultrasound for both analysis and therapy together. Microbubbles or nanobubbles directed at the molecular level will allow medical doctors to make a final prognosis of an illness using ultrasound imaging and then immediately check out a restorative ultrasound treatment.
Today there exists only 1 FDA-approved treatment for ischemic heart stroke; i. e. , the serine protease tissue-type plasminogen activator (tPA). Inside the aftermath of the failed stroke medical trials with the nitrone spin capture/radical scavenger, NXY-059, lots of articles raised the question: are we doing the right thing? Is the pet research truly translational in discovering new agents for stroke treatment? This review summarizes the existing state of affairs with plasminogen activators in thrombolytic remedy. Furthermore to healing value, potential side ramifications of tPA also are present that aggravate heart stroke damage and offset the benefits provided by reperfusion of the occluded artery. Thus, combinational options (ultrasound only or with microspheres/nanobubbles, mechanical dissociation of clot, turned on health proteins C (APC), plasminogen activator inhibitor-1 (PAI-1), neuroserpin and CDP-choline) that can offset tPA harmful side effects and improve efficiency are also talked about here. Desmoteplase, a plasminogen activator derived from the saliva of Desmodus rotundus vampire bat, antagonizes vascular tPA-induced neurotoxicity by competitively binding to low-density lipoprotein related-receptors (LPR) at the blood-brain hurdle (BBB) interface, minimizing the tPA uptake into brain parenchyma. tPA can also switch on matrix metalloproteinases (MMPs), a family group of endopeptidases made up of 24 mammalian enzymes that mostly catalyze the turnover and degradation of the extracellular matrix (ECM). MMPs have been implicated in BBB malfunction and neuronal personal injury in the first times after heart stroke, but also contribute to vascular remodeling, angiogenesis, neurogenesis and axonal regeneration through the later repair period after stroke. tPA, directly or by activation of MMP-9, could have beneficial effects on restoration after stroke by promoting neurovascular repair through vascular endothelial progress factor (VEGF). However, any treatment regimen directed at MMPs must consider their pleiotropic dynamics and the probability of either beneficial or detrimental effects that may be based upon the timing of the procedure in relation to the stage of brain damage.
Combining diagnostic and restorative processes into one (theranostics) and enhancing their selectivity to the cellular level may offer significant benefits in a variety of research and disease systems and presently is not backed with efficient methods and agents. We've developed an innovative way predicated on the platinum nanoparticle-generated transient photothermal vapor nanobubbles, that we make reference to as plasmonic nanobubbles (PNB). After delivery and clusterization of the platinum nanoparticles (NP) to the prospective skin cells the intracellular PNBs were optically generated and controlled through the laser fluence. The PNB action was tuned in specific living cells from non-invasive high-sensitive imaging at lower fluence to disruption of the cellular membrane at higher fluence. We have achieved non-invasive 50-fold amplification of the optical scattering amplitude with the PNBs (relative to that of NPs), selective mechanical and fast damage to specific skin cells with bigger PNBs, and optical instruction of the destruction through the damage-specific impulses of the bubbles. Thus the PNBs acted as tunable theranostic agents at the cellular level and in one process that contain supported diagnosis, therapy and instruction of the treatment.
The definitive goal in the treating acute ischemic heart stroke is quick arterial recanalization. Thrombolysis with recombinant structure plasminogen activator (rtPA) is useful in humans, but shows significant problems including sluggish and imperfect recanalization and regular bleeding complications. Limited therapeutic home window (the first three hours after starting point) is the major limitation leading to reach too few patients. Therefore, adjunctive therapies stretching the reperfusion time home window, increasing effectiveness and minimizing side ramifications of rtPA are needed. Ultrasound augmentation of rtPA-mediated thrombolysis is recommended to overcome a few of these problems, but low-frequency ultrasound (significantly less than 1 MHz) is not safe and high rate of recurrence ultrasound (2 MHz) is very little effective. Researchers claim that normobaric hyperoxia (NBO) may boost the effectiveness of ultrasound and rtPA blend in addition to its efficacy in severe ischemic stroke. Briefly, NBO enhances arterial partial oxygen pressure (pO2) significantly up to 6-flip. Increase of pO2 results within an increase of dissolved air in the blood matching to Henry's legislation. Enhanced dissolved oxygen boosts gas nuclei formation around and inside of the clot, and decreases the Blake threshold. Under ultrasound field, these small gas nuclei form nanobubbles which energy inertial cavitation as substrates, and for that reason boost the clot fragmentation and lysis. This hypothesis has not been tested so far. The combo of rtPA, restorative ultrasound and NBO may become more efficacious than rtPA together or its blend with ultrasound as acute heart stroke treatment modality, because each has different and probably additive system of action.