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1.
J Int Med Res ; 51(8): 3000605231187801, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37548224

ABSTRACT

Temporal lobe epilepsy is the most common focal epilepsy syndrome and has a broad spectrum of presentations. Nevertheless, isolated vestibular symptoms without other symptoms typical of temporal lobe seizures are relatively rare. Here, we report one female patient who suffered from chronic refractory vertigo and had inappropriate pharmacotherapy for several years. Eventually, epileptic vertigo and dizziness (ictal vertigo) were accurately diagnosed by detailed history taking and serial examinations assisted by sphenoid electroencephalography. Awareness of this unique syndrome is important in the diagnosis of patients with epileptic vertigo and dizziness.


Subject(s)
Epilepsy, Temporal Lobe , Humans , Female , Epilepsy, Temporal Lobe/complications , Epilepsy, Temporal Lobe/diagnosis , Dizziness , Vertigo/complications , Vertigo/diagnosis , Seizures/complications , Seizures/diagnosis , Electroencephalography
2.
J Formos Med Assoc ; 121(1 Pt 1): 187-192, 2022 Jan.
Article in English | MEDLINE | ID: mdl-33736903

ABSTRACT

BACKGROUND/PURPOSE: FAST and Stroke-112 are two campaigns to reduce the emergency room arrival time of stroke patients. No study has compared the effectiveness of these campaigns. This study aimed to compare recalling capacity of people in these two campaigns. METHODS: A prospective, open-label randomized study was conducted in 2019. Recall ability for the items of the two campaigns on the 5th and 30th days post-education was compared using non-parametric methods. Subject characteristics including age, education level, presence of stroke in co-residents, and habitual language were evaluated using multiple ordered logistic regression. RESULTS: There were 202 participants in FAST group and 193 participants in Stroke-112 group who completed the study. No differences were observed between the two groups in recall ability, either on day 5 or day 30 after receiving education. For both campaigns, recall ability was better for signs in the face (FAST: 87.1%, Stroke-112: 86.5%) and the arm (FAST: 87.1%, Stroke-112: 88.1%) than for abnormality in speech (FAST: 78.7%, Stroke-112: 76.7%) on day 5. Recall ability on day 30 remained the same only for the arm item (FAST: 86.1%, Stroke-112: 88.6%). The recall ability was correlated to education level equal or more than 7 years in FAST group, and was inversely correlated to age and being a stroke patient in Stroke-112 group. CONCLUSION: We found no difference in recall ability between the 2 campaigns. Education level was associated with recallability of FAST, and age and stroke history were associated with recallability of Stroke-112.


Subject(s)
Stroke , Educational Status , Emergency Service, Hospital , Humans , Prospective Studies , Stroke/epidemiology , Taiwan/epidemiology
3.
Int J Mol Sci ; 22(17)2021 Aug 26.
Article in English | MEDLINE | ID: mdl-34502166

ABSTRACT

Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of typical chemotherapeutics among cancer survivors. Despite the recent progress, the effective prevention and treatment strategies for CIPN remain limited. Better understanding of the pathogenesis of CIPN may provide new niches for developing a new ideal therapeutic strategy. This review summarizes the current understanding of CIPN and current recommendations along with completed/active clinical trials and aims to foster translational research to improve the development of effective strategies for managing CIPN.


Subject(s)
Antineoplastic Agents/adverse effects , Disease Susceptibility , Drug-Related Side Effects and Adverse Reactions/etiology , Integrative Medicine , Peripheral Nervous System Diseases/etiology , Antineoplastic Agents/therapeutic use , Clinical Trials as Topic , Combined Modality Therapy , Disease Management , Drug-Related Side Effects and Adverse Reactions/diagnosis , Drug-Related Side Effects and Adverse Reactions/therapy , Humans , Integrative Medicine/methods , Integrative Medicine/trends , Peripheral Nervous System Diseases/diagnosis , Peripheral Nervous System Diseases/therapy , Treatment Outcome
4.
J Vet Sci ; 22(5): e60, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34423598

ABSTRACT

BACKGROUND: Echocardiography is a primary tool used by veterinarians to evaluate heart diseases. In recent years, various studies have targeted standard echocardiographic values for different breeds. Reference data are currently lacking in Maltese dogs and it is important to fill this gap as this breed is predisposed to myxomatous mitral valve disease, which is a volume overload disease. OBJECTIVES: To establish the normal echocardiographic parameters for Maltese dogs. METHODS: In total, 23 healthy Maltese dogs were involved in this study. Blood pressure measurements, thoracic radiography, and complete transthoracic echocardiography were performed. The effects of body weight, age and sex were evaluated, and the correlations between weight and linear and volumetric dimensions were calculated by regression analysis. RESULTS: The mean vertebral heart size was 9.1 ± 0.4. Aside from the ejection fraction, fractional shortening, and the left atrial to aorta root ratio, all the other echocardiographic parameters were significantly correlated with weight. CONCLUSION: This study describes normal echocardiographic parameters that may be useful in the echocardiographic evaluation of Maltese dogs.


Subject(s)
Blood Pressure , Body Weight , Echocardiography/veterinary , Radiography, Thoracic/veterinary , Age Factors , Animals , Dogs , Female , Male , Reference Values , Sex Factors
5.
Mar Drugs ; 19(6)2021 May 26.
Article in English | MEDLINE | ID: mdl-34073219

ABSTRACT

Cardiovascular diseases such as atherosclerosis and aortic valve sclerosis involve inflammatory reactions triggered by various stimuli, causing increased oxidative stress. This increased oxidative stress causes damage to the heart cells, with subsequent cell apoptosis or calcification. Currently, heart valve damage or heart valve diseases are treated by drugs or surgery. Natural antioxidant products are being investigated in related research, such as fucoxanthin (Fx), which is a marine carotenoid extracted from seaweed, with strong antioxidant, anti-inflammatory, and anti-tumor properties. This study aimed to explore the protective effect of Fx on heart valves under high oxidative stress, as well as the underlying mechanism of action. Rat heart valve interstitial cells under H2O2-induced oxidative stress were treated with Fx. Fx improved cell survival and reduced oxidative stress-induced DNA damage, which was assessed by cell viability analysis and staining with propidium iodide. Alizarin Red-S analysis indicated that Fx has a protective effect against calcification. Furthermore, Western blotting revealed that Fx abrogates oxidative stress-induced apoptosis via reducing the expression of apoptosis-related proteins as well as modulate Akt/ERK-related protein expression. Notably, in vivo experiments using 26 dogs treated with 60 mg/kg of Fx in combination with medical treatment for 0.5 to 2 years showed significant recovery in their echocardiographic parameters. Collectively, these in vitro and in vivo results highlight the potential of Fx to protect heart valve cells from high oxidative stress-induced damage.


Subject(s)
Calcification, Physiologic/drug effects , Cardiotonic Agents/pharmacology , Heart Valves/drug effects , Xanthophylls/pharmacology , Animals , Cell Survival/drug effects , Dogs , Heart Valves/pathology , Hydrogen Peroxide , Oxidative Stress/drug effects , Rats
6.
Dalton Trans ; 49(26): 9035-9047, 2020 Jul 14.
Article in English | MEDLINE | ID: mdl-32567620

ABSTRACT

This paper proposes a novel µ-hydroxo-bridged dinuclear macrocyclic zinc complex, {[Zn(C10H20N8)]2(OH)}(BF4)3. The structure was determined by X-ray crystallography: Monoclinic, C2/c, a = 25.4632(6), b = 10.9818(3), c = 15.7522(4) Å, Z = 8, R1 = 0.0233, wR2 = 0.0557, based on reflections I > 2σ(I). The complex was successfully reacted with graphene oxide to form a µ-hydroxo-bridged dinuclear macrocyclic Zn complex/reduced graphene oxide composite. To evenly disperse the Zn- and N-rich complex onto the surface of the reduced graphene oxide, and to enhance the electrocatalytic property of the graphene composites, a soluble molecular grafting method was used here. The graphene-based composites were applied as the counter electrodes (CEs) of dye-sensitized solar cells. Current density-voltage measurements revealed that the conversion efficiency of the GO/Zn (1 : 10) sample was 7.78%, which was better than that of Pt CE (7.49%). GO/Zn (1 : 10) CE exhibited the lowest impedance (RCE = 9.90 Ω), which was better than that of Pt CE (RCE = 66.1 Ω), showing that GO/Zn CEs can reduce the impedance at the CE/electrolyte interface. The proposed method is simple, and the composite materials can potentially replace conventional Pt, optimizing efficiency and reducing production cost.

7.
Dalton Trans ; 49(25): 8516-8527, 2020 Jul 07.
Article in English | MEDLINE | ID: mdl-32525193

ABSTRACT

Nickel-doped FeS2/rGO composites were synthesized as multifunctional materials via a facile hydrothermal method. The synthesized materials were characterized with XRD, FESEM, XPS, and TEM-SAED for structural, morphological and chemical studies. To study their electrochemical properties, all the synthesized composites were subjected to cyclic voltammetry tests. The optimum composite revealed high catalytic activity with high peak current density, limiting current, and efficiency of 7.60% for DSSC, which surpassed that of a platinum-based counter electrode (6.69%). The efficiency of the DSSC was significantly supported by interfacial studies and electron lifetime studies, and it exhibited lower charge transfer resistance and higher electron lifetime, respectively. Moreover, the fabricated DSSCs with high efficiency were subjected to transient photo-response studies and showed a stable current response with multiple photo-ON and OFF cycles for a period of 600 s. To broaden the application of the synthesized material, it was used as an electrochemical sensor for the efficient sensing of hydrogen peroxide (H2O2). The sensing electrode was modified with the optimum Ni-doped FeS2/rGO composite, and voltammetric detection was carried out in the hydrogen peroxide concentration range of 4-100 µM. Thus, the synthesized material can be applied in DSSCs and as an electrochemical H2O2 sensor.

8.
Sci Rep ; 10(1): 4338, 2020 03 09.
Article in English | MEDLINE | ID: mdl-32152413

ABSTRACT

Ultrasound (US) has been found to rejuvenate and invigorate the hair follicles, increase the size of hair shafts, and promote new hair growth. Our present study found that dual-frequency US-mediated microbubble (MB) cavitation significantly enhanced minoxidil (Mx) delivery in both in vitro and in vivo models, while increasing the hair growth efficacy compared to single-frequency US sonication. The in vitro experiments showed that cavitation activity was enhanced more significantly during dual-frequency sonication than single-frequency sonication in higher concentration of MBs. The pigskin penetration depth in the group in which dual-frequency US was combined with MBs was 1.54 and 2.86 times greater than for single-frequency US combined with MBs and in the control group, respectively; the corresponding increases in the release rate of Mx at 18 hours in in vitro Franz-diffusion-cell experiments were 24.9% and 43.7%. During 21 days of treatment in C57BL/6J mice experiments, the growth rate at day 11 in the group in which dual-frequency US was combined with MBs increased by 2.07 times compared to single-frequency US combined with MBs. These results indicate that dual-frequency US-mediated MB cavitation can significantly increase both skin permeability and transdermal drug delivery. At the same US power density, hair growth was greater in the group with dual-frequency US plus MBs than in the group with single-frequency US plus MBs, without damaging the skin in mice.


Subject(s)
Drug Delivery Systems , Hair Follicle/drug effects , Hair/drug effects , Hair/growth & development , Microbubbles , Minoxidil/administration & dosage , Ultrasonic Waves , Administration, Cutaneous , Animals , Drug Delivery Systems/methods , Drug Delivery Systems/standards , Mice , Minoxidil/pharmacokinetics , Models, Animal , Models, Biological , Permeability , Sonication
9.
Brain Stimul ; 13(1): 35-46, 2020.
Article in English | MEDLINE | ID: mdl-31575487

ABSTRACT

BACKGROUND: Epilepsy is a neurological disorder characterized by abnormal neuron discharge, and one-third of epilepsy patients suffer from drug-resistant epilepsy (DRE). The current management for DRE includes epileptogenic lesion resection, disconnection, and neuromodulation. Neuromodulation is achieved through invasive electrical stimulus including deep brain stimulation, vagus nerve stimulation, or responsive neurostimulation (RNS). As an alternative therapy, transcranial focused ultrasound (FUS) can transcranially and non-invasively modulate neuron activity. OBJECTIVE: This study seeks to verify the use of FUS pulsations to suppress spikes in an acute epileptic small-animal model, and to investigate possible biological mechanisms by which FUS pulsations interfere with epileptic neuronal activity. METHODS: The study used a total of 76 Sprague-Dawley rats. For the epilepsy model, rats were administered pentylenetetrazol (PTZ) to induce acute epileptic-like abnormal neuron discharges, followed by FUS exposure. Various ultrasound parameters were set to test the epilepsy-suppressing effect, while concurrently monitoring and analyzing electroencephalogram (EEG) signals. Animal behavior was monitored and histological examinations were conducted to evaluate the hazard posed by ultrasound exposure and the expression of neuronal activity markers. Western blotting was used to evaluate the correlation between FUS-induced epileptic suppression and the PI3K-mTOR signaling pathway. RESULTS: We observed that FUS pulsations effectively suppressed epileptic activity and observed EEG spectrum oscillations; the spike-suppressing effect depended on the selection of ultrasound parameters and highly correlated with FUS exposure level. Expression level changes of c-Fos and GAD65 were confirmed in the cortex and hippocampus, indicating that FUS pulsations deactivated excitatory cells and activated GABAergic terminals. No tissue damage, inflammatory response, or behavioral abnormalities were observed in rats treated with FUS under these exposure parameters. We also found that the FUS pulsations down-regulated the S6 phosphorylation and decreased pAKT expression. CONCLUSION: Our results suggest that pulsed FUS exposure effectively suppresses epileptic spikes in an acute epilepsy animal model, and finds that ultrasound pulsation interferes with neuronal activity and affects the PTZ-induced PI3K-Akt-mTOR pathway, which might help explain the mechanism underlying ultrasound-related epileptic spike control.


Subject(s)
Epilepsy/chemically induced , Epilepsy/therapy , Pentylenetetrazole/toxicity , Ultrasonic Therapy/methods , Animals , Cerebral Cortex/physiopathology , Electroencephalography/methods , Epilepsy/physiopathology , Heart Rate/physiology , Hippocampus/physiopathology , Male , Rats , Rats, Sprague-Dawley
10.
Brain Stimul ; 12(5): 1143-1150, 2019.
Article in English | MEDLINE | ID: mdl-31079989

ABSTRACT

BACKGROUND: Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the gene encoding the huntingtin (Htt) protein, which results in a protein containing an abnormally expanded polyglutamine (polyQ) sequence. The expanded polyQ in the Htt protein is toxic to brain cells. No therapy exists to delay disease progression. METHODS: This study describes a gene-liposome system that synergistically applied focused ultrasound (FUS)-blood-brain barrier (BBB) opening for rescuing motor and neuropathological impairments when administered from pre to post-symptomatic transgenic mouse models of HD. DPPC liposomes (LPs) are designed to carry glia cell line-derived neurotrophic factor (GDNF) plasmid DNA (GDNFp) to form a GDNFp-liposome (GDNFp-LPs) complex. Pulsed FUS exposure with microbubbles (MBs) was used to induce BBB opening for non-viral, non-invasive, and targeted gene delivery into the central nervous system (CNS) for therapeutic purposes. RESULTS: FUS-gene therapy significantly improved motor performance with GDNFp-LPs + FUS treated HD mice equilibrating longer periods in the animal behavior. Reflecting the improvements observed in motor function, GDNF overexpression results in significantly decreased formation of polyglutamine-expanded aggregates, reduced oxidative stress and apoptosis, promoted neurite outgrowth, and improved neuronal survival. Immunoblotting and histological staining further confirmed the neuroprotective effect from delivery of GDNF genes to neuronal cells. CONCLUSIONS: This study suggests that the GDNFp-LPs plus FUS sonication can provide an effective gene therapy to achieve local extravasation and triggered gene delivery for non-invasive in vivo treatment of CNS diseases.


Subject(s)
Blood-Brain Barrier , Capillary Permeability/physiology , Gene Transfer Techniques , Glial Cell Line-Derived Neurotrophic Factor/administration & dosage , Huntington Disease/therapy , Ultrasonic Therapy/methods , Animals , Blood-Brain Barrier/metabolism , Brain/metabolism , Disease Models, Animal , Genetic Therapy/methods , Glial Cell Line-Derived Neurotrophic Factor/metabolism , Huntington Disease/genetics , Huntington Disease/metabolism , Mice , Mice, Transgenic , Microbubbles
11.
Sci Rep ; 8(1): 17720, 2018 12 07.
Article in English | MEDLINE | ID: mdl-30531863

ABSTRACT

Focused ultrasound (FUS) with the presence of microbubbles induces blood brain barrier (BBB) opening in targeted areas and facilitates drug delivery. However, recent studies have indicated that FUS-BBB opening with excessive exposure levels may be associated with inflammatory response and cellular/tissue damage. Multiple weekly FUS exposures have been shown to be safe for human subjects. However the effect of more frequent FUS exposures is still unknown. This study examines whether frequent focused ultrasound blood brain barrier opening is associated with aggravated behavioral, histopathologic change or brain tissue damage. Two protocols of focused ultrasound blood brain barrier opening were devised using different microbubble doses (0.15 µl/kg and 0.4 µl/kg). Focused ultrasound exposure at a threshold level of BBB-opening, below-threshold level, or above level for intracerebral hemorrhage were delivered every 2 days. Animal behavioral and physiological changes were examined and recorded. Brain tissue was examined for hemorrhage and apoptosis. Results indicate that frequent exposure of excessive focused ultrasound (1.4 mechanical index) produced minor and short-term behavioral changes despite significant tissue damage, while frequent BBB opening with threshold or below-threshold FUS exposure (0.33-0.8 mechanical index) did not cause behavioral or histological change. Immunofluorescent examination of rat brain tissue indicated that excessive doses of microbubble administration induce an apparent cellular apoptotic response, which may be exacerbated by intracerebral hemorrhage. Experimental results suggest that frequent focused ultrasound blood brain barrier opening with sufficient ultrasound exposure level and a microbubble dose can be safe and pose minimal risk to brain tissue.


Subject(s)
Blood-Brain Barrier/metabolism , Brain/metabolism , Animals , Apoptosis/physiology , Biological Transport/physiology , Coloring Agents/metabolism , Drug Delivery Systems/methods , Hemorrhage/metabolism , Male , Microbubbles , Rats , Rats, Sprague-Dawley , Ultrasonography/methods
12.
Article in English | MEDLINE | ID: mdl-30010555

ABSTRACT

Focused ultrasound phased array systems have attracted increased attention for brain therapy applications. However, such systems currently lack a direct and real-time method to intraoperatively monitor ultrasound pressure distribution for securing treatment. This study proposes a dual-mode ultrasound phased array system design to support transmit/receive operations for concurrent ultrasound exposure and backscattered focal beam reconstruction through a spherically focused ultrasound array. A 256-channel ultrasound transmission system was used to transmit focused ultrasonic energy (full 256 channels), with an extended implementation of multiple-channel receiving function (up to 64 channels) using the same 256-channel ultrasound array. A coherent backscatter-received beam formation algorithm was implemented to map the point spread function (PSF) and focal beam distribution under a free-field/transcranial environment setup, with the backscattering generated from a strong scatterer (a point reflector or a microbubble-perfused tube) or a weakly scattered tissue-mimicking graphite phantom. Our results showed that PSF and focal beam can be successfully reconstructed and visualized in free-field conditions and can also be transcranially reconstructed following skull-induced aberration correction. In vivo experiments were conducted to demonstrate its capability to preoperatively and semiquantitatively map a focal beam to guide blood-brain barrier opening. The proposed system may have potential for real-time guidance of ultrasound brain intervention, and may facilitate the design of a dual-mode ultrasound phased array for brain therapeutic applications.


Subject(s)
Brain/diagnostic imaging , Ultrasonic Therapy , Ultrasonography , Algorithms , Animals , Blood-Brain Barrier/diagnostic imaging , Equipment Design , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Microbubbles , Phantoms, Imaging , Rats , Skull/diagnostic imaging , Ultrasonic Therapy/instrumentation , Ultrasonic Therapy/methods , Ultrasonography/instrumentation , Ultrasonography/methods
13.
Toxicol Lett ; 290: 116-122, 2018 Jun 15.
Article in English | MEDLINE | ID: mdl-29551592

ABSTRACT

CONTEXT: Arsenic poisoning commonly occurs through exposure to water contaminated with arsenic and causes long-term symptoms. Of all the arsenic derivatives, arsenite is the one of the most toxic compounds. However, the toxicity of arsenite during developmental stages is still unclear. OBJECTIVE: In this study, we performed a metabolomic analysis of arsenite responses in embryonic zebrafish. MATERIALS AND METHODS: Embryonic zebrafish were used as an animal model in this study. They were exposed to sodium arsenite under different concentrations (0.5, 1.0, 2.0, and 5.0 mg/L) in 24 h, 48 h and 72 h post fertilization. Changes in morphology were observed through a light microscope. Changes in metabolomics were identified using an ultraperformance liquid chromatography quadrupole time-of-flight system. RESULTS: The IC50 range was 0.75 ±â€¯0.25 mg/L. Compared with the control group, the embryonic lethality rate decreased to 33.3% under 1.0 mg/L of arsenite treatment, whereas it decreased to 20.0% under 2.0 mg/L of arsenite treatment. Numerous body axis curvatures were also observed under treatment with 2.0 and 5.0 mg/L of arsenic. Pericardium and yolk sac edema were randomly discovered and found to worsen over time. Moreover, the 10 metabolites with the highest variable importance in projection score were identified as potential biomarkers for arsenic exposure. CONCLUSION: Arsenic exposure not only leads to a change in the morphology of embryonic zebrafish but also disturbs the metabolism of zebrafish in early developmental stages.


Subject(s)
Arsenites/toxicity , Embryo, Nonmammalian/drug effects , Metabolomics , Zebrafish/embryology , Animals , Arachidonic Acids/physiology , Biomarkers , Dose-Response Relationship, Drug , Embryo, Nonmammalian/metabolism , Endocannabinoids/physiology , Glycerides/physiology , ROC Curve
14.
Sci Rep ; 8(1): 4151, 2018 03 07.
Article in English | MEDLINE | ID: mdl-29515222

ABSTRACT

Focused ultrasound (FUS) exposure with microbubbles can transiently open the blood-brain barrier (BBB) to deliver therapeutic molecules into CNS tissues. However, delivered molecular distribution/concentration at the target need to be controlled. Dynamic Contrast-Enhanced Magnetic-Resonance Imaging (DCE-MRI) is a well-established protocol for monitoring the pharmacokinetic/pharmacodynamic behavior of FUS-BBB opening. This study investigates the feasibility of using DCE-MRI to estimate molecular CNS penetration under various exposure conditions and molecule sizes. In the 1st stage, a relationship among the imaging index Ktrans, exposure level and molecular size was calibrated and established. In the 2nd stage, various exposure levels and distinct molecules were applied to evaluate the estimated molecular concentration discrepancy with the quantified ones. High correlation (r2 = 0.9684) between Ktrans and transcranial mechanical index (MI) implies Ktrans can serve as an in vivo imaging index to mirror FUS-BBB opening scale. When testing various molecules with the size ranging 1-149 kDa, an overall correlation of r2 = 0.9915 between quantified and predicted concentrations was reached, suggesting the established model can provide reasonably accurate estimation. Our work demonstrates the feasibility of estimating molecular penetration through FUS-BBB opening via DCE-MRI and may facilitate development of FUS-induced BBB opening in brain drug delivery.


Subject(s)
Blood-Brain Barrier , Contrast Media , Drug Delivery Systems/methods , Magnetic Resonance Imaging , Microbubbles , Ultrasonic Therapy , Animals , Blood-Brain Barrier/diagnostic imaging , Blood-Brain Barrier/metabolism , Contrast Media/pharmacokinetics , Contrast Media/pharmacology , Male , Mice , Rats, Sprague-Dawley
15.
Sci Rep ; 7(1): 1638, 2017 05 09.
Article in English | MEDLINE | ID: mdl-28487554

ABSTRACT

Combination therapy with focused ultrasound (FUS) and a neuroprotective agent, BNG-1, was examined in an acute carotid thrombotic occlusion model using LED irradiation in rat to improve the thrombolytic effect of rt-PA. Seven treatment groups included (A) intravenous bolus injection of 0.45 mg/kg rt-PA, (B) intravenous bolus injection of 0.9 mg/kg, (C) sonothrombolysis with FUS alone, (D) oral administration of 2 g/kg BNG-1 for 7 days alone, (E) A + D, (F) A + C, and (G) A + C + D. Four comparison groups were made including (H) 0.45 mg/kg rt-PA 20% bolus +80% IV fusion + FUS, (I) 0.9 mg/kg rt-PA with 10% bolus + 90% intravenous fusion, (J) B + C, (K) B + D. At 7 days after carotid occlusion, small-animal carotid ultrasound and 7 T MR angiography showed the recanalization rate of ≤50% stenosis was 50% in group B and 83% in group I, but 0% in groups A and C and 17% in group D. Combination therapy improved recanalization rate to 50-63% in groups E and F, to 67-83% in groups J and K, and to 100% in groups G and H. Our study demonstrated combination therapy with different remedies can be a feasible strategy to improve the thrombolytic effect of rt-PA.


Subject(s)
Carotid Artery Thrombosis/drug therapy , Neuroprotective Agents/therapeutic use , Thrombolytic Therapy , Ultrasonics , Angiography , Animals , Magnetic Resonance Imaging , Male , Neuroprotective Agents/pharmacology , Phosphodiesterase Inhibitors/pharmacology , Platelet Endothelial Cell Adhesion Molecule-1/metabolism , Rats, Sprague-Dawley
16.
Sci Rep ; 7: 46689, 2017 04 20.
Article in English | MEDLINE | ID: mdl-28425493

ABSTRACT

Microbubbles (MBs) serve as a critical catalyst to amplify local cavitation in CNS capillary lumen to facilitate focused ultrasound (FUS) to transiently open the blood-brain barrier (BBB). However, limited understanding is available regarding the effect of different microbubbles to induce BBB opening. The aim of this study is to characterize different MBs on their effect in FUS-induced BBB opening. Three MBs, SonoVue, Definity, and USphere, were tested, with 0.4-MHz FUS exposure at 0.62-1.38 of mechanical index (MI) on rats. Evans blue, dynamic contrast-enhanced (DCE) MRI and small-animal ultrasound imaging were used as surrogates to allow molecule-penetrated quantification, BBB-opened observation, and MBs circulation/persistence. Cavitation activity was measured via the passive cavitation detection (PCD) setup to correlate with the exposure level and the histological effect. Under given and identical MB concentrations, the three MBs induced similar and equivalent BBB-opening effects and persistence. In addition, a treatment paradigm by adapting exposure time is proposed to compensate MB decay to retain the persistence of BBB-opening efficiency in multiple FUS exposures. The results potentially improve understanding of the equivalence among MBs in focused ultrasound CNS drug delivery, and provide an effective strategy for securing persistence in this treatment modality.


Subject(s)
Blood-Brain Barrier/drug effects , Contrast Media/administration & dosage , Microbubbles , Ultrasonic Therapy/methods , Animals , Blood-Brain Barrier/diagnostic imaging , Blood-Brain Barrier/metabolism , Capillary Permeability/drug effects , Magnetic Resonance Imaging/methods , Male , Rats, Sprague-Dawley
17.
J Colloid Interface Sci ; 495: 111-121, 2017 06 01.
Article in English | MEDLINE | ID: mdl-28189954

ABSTRACT

A novel series of reduced graphene oxide (RGO)/macrocyclic iron (Fe) complex hybrid materials were synthesized and then used in the production of counter electrodes (CEs) for dye-sensitized solar cells (DSSCs). The electrode properties of various CEs were comprehensively analyzed using scanning electron microscopy, transmission electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, energy dispersive spectroscopy, Raman spectroscopy, X-ray diffraction, and cyclic voltammetry analyses. DSSCs, based on various CEs, were characterized using current density-voltage, incident monochromatic photon-to-current conversion efficiency, and electrochemical impedance spectroscopy measurements. DSSCs fabricated using the RGO/macrocyclic Fe nanocomposite CEs yielded an efficiency of 6.75%. The RGO/Fe CEs exhibited efficient electrocatalytic capability because catalytic Fe particles were uniformly distributed on the surface of RGO. The results indicated that a DSSC with a RGO/Fe CE can exhibit an efficiency comparable to that of a platinum (Pt) CE DSSC and can therefore replace conventional Pt CE DSSCs to lower the cost of solar cells.

18.
ACS Appl Mater Interfaces ; 9(13): 11942-11949, 2017 Apr 05.
Article in English | MEDLINE | ID: mdl-28177598

ABSTRACT

The surface morphology in polycrystalline silicon (poly-Si) film is an issue regardless of whether conventional excimer laser annealing (ELA) or the newer metal-induced lateral crystallization (MILC) process is used. This paper investigates the stress distribution while undergoing long-term mechanical stress and the influence of stress on electrical characteristics. Our simulated results show that the nonuniform stress in the gate insulator is more pronounced near the polysilicon/gate insulator edge and at the two sides of the polysilicon protrusion. This stress results in defects in the gate insulator and leads to a nonuniform degradation phenomenon, which affects both the performance and the reliability in thin-film transistors (TFTs). The degree of degradation is similar regardless of bending axis (channel-length axis, channel-width axis) or bending type (compression, tension), which means that the degradation is dominated by the protrusion effects. Furthermore, by utilizing long-term electrical bias stresses after undergoing long-tern bending stress, it is apparent that the carrier injection is severe in the subchannel region, which confirms that the influence of protrusions is crucial. To eliminate the influence of surface morphology in poly-Si, three kinds of laser energy density were used during crystallization to control the protrusion height. The device with the lowest protrusions demonstrates the smallest degradation after undergoing long-term bending.

19.
Sci Rep ; 6: 33264, 2016 09 15.
Article in English | MEDLINE | ID: mdl-27630037

ABSTRACT

Focused ultrasound (FUS) with microbubbles can temporally open the blood-brain barrier (BBB), and the cavitation activities of microbubbles play a key role in the BBB-opening process. Previous attempts used contrast-enhanced magnetic resonance imaging (CE-MRI) to correlate the mechanical index (MI) with the scale of BBB-opening, but MI only partially gauged acoustic activities, and CE-MRI did not fully explore correlations of pharmacodynamic/pharmacokinetic behaviors. Recently, the cavitation index (CI) has been derived to serve as an indicator of microbubble-ultrasound stable cavitation, and may also serve as a valid indicator to gauge the level of FUS-induced BBB opening. This study investigates the feasibility of gauging FUS-induced BBB opened level via the two indexes, MI and CI, through dynamic contrast-enhanced (DCE)-MRI analysis as well as passive cavitation detection (PCD) analysis. Pharmacodynamic/pharmacokinetic parameters derived from DCE-MRI were characterized to identify the scale of FUS-induced BBB opening. Our results demonstrated that DCE-MRI can successfully access pharmacodynamic/pharmacokinetic BBB-opened behavior, and was highly correlated both with MI and CI, implying the feasibility in using these two indices to gauge the scale of FUS-induced BBB opening. The proposed finding may facilitate the design toward using focused ultrasound as a safe and reliable noninvasive CNS drug delivery.


Subject(s)
Blood-Brain Barrier/diagnostic imaging , Drug Delivery Systems , Magnetic Resonance Imaging/methods , Ultrasonic Therapy/methods , Animals , Blood-Brain Barrier/drug effects , Blood-Brain Barrier/physiopathology , Contrast Media/pharmacology , Disease Models, Animal , Humans , Microbubbles/therapeutic use , Rats
20.
ACS Appl Mater Interfaces ; 8(41): 27832-27842, 2016 Oct 19.
Article in English | MEDLINE | ID: mdl-27671011

ABSTRACT

Two new organic dyes-BPDTA and BTTA-possessing dual D-π-A units have been synthesized, characterized, and employed as efficient sensitizers for dye-sensitized solar cells. The two individual D-π-A, which are based on (E)-3-(5'-(4-(bis(4-(hexyloxy)phenyl)amino)phenyl)-[2,2'-bithiophen]-5-yl)-2-cyanoacrylic acid unit (D21L6), are connected directly between phenylene or thiophene within linear π-conjugated backbone to constitute a highly twisted architecture for suppressing the dye aggregation. The new dianchoring dyes exhibited pronounced absorption profile with higher molar extinction coefficient, which is consistent with the results obtained from density functional theory (DFT) calculations. The theoretical analysis also indicated that the charge transfer transition is mainly constituted of HOMO/HOMO-1 to LUMO/LUMO+1 that were found to be located on donor and acceptor segments, respectively. Theoretical calculations give the distance between two binding sites of 19.50 Å for BPDTA and 12.04 Å for BTTA. The proximity between two anchoring units of BTTA results in superior dye loading and, hence, higher cell efficiency. The BTTA-based device yielded an optimized efficiency of 6.86%, compared to 6.61% for the BPDTA-based device, whereas the model sensitizer D21L6 only delivered an inferior performance of 5.33% under similar conditions. Our molecular design strategy thus opens up a new horizon to establish efficient dianchoring dyes.

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