http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Paramagnetic Gd<sup>3+</sup> labeled red blood cells for magnetic resonance angiography
Aryal, S.,Stigliano, C.,Key, J.,Ramirez, M.,Anderson, J.,Karmonik, C.,Fung, S.,Decuzzi, P. IPC Science and Technology Press 2016 Biomaterials Vol.98 No.-
<P>Despite significant advances in contrast enhanced-magnetic resonance angiography, the lack of truly blood-pool agents with long circulating property is limiting the clinical impact of this imaging technique. The terminal half-life for blood elimination of most small molecular weight gadolinium (Gd) based extracellular fluid agents is about 1.5 h when administered intravenously to subjects with normal renal function. The small size of these extracellular fluid agents does not prevent them from extravasating, especially from damaged vessels which are generally hyperpermeable. Therefore, the development of novel, clinically relevant blood pool contrast agents is critically needed to improve outcomes in the prevention, detection, and treatment of vascular diseases. We have demonstrated the fusion strategies in which the Gd-liposome without any stealth property radically fuses with red blood cells (RBCs) forming MR glowing Gd-RBC with the order of magnitude enhancements in circulation half-life (t(1/2) = 50 h) and r(1) relaxivity (r(1) = 19.0 mM(-1) s(-1)) of Gd. The in vivo contrast enhancement of Gd-RBC was studied by using 3T clinical MR scanner for extended period of time, which clearly visualized the abdominal aorta. In summary, the vascular delivery of blood pool agents may benefit from carriage by RBCs because it naturally stays within the vascular lumen. (C) 2016 Elsevier Ltd. All rights reserved.</P>
Choi B.,Aryal M. 한국물리학회 2023 Current Applied Physics Vol.49 No.-
The effect of gold nanoparticles embedded in ferromagnetic Ni80Fe20 thin films on the magneto-optical response was studied by means of spectroscopic ellipsometry and magneto-optical Kerr effect spectroscopy. Au nanoparticles (Au NPs) are prepared by using post-annealing of Au films on SiO2/Si substrate, and Ni80Fe20 film was deposited on top of Au NPs. A significant enhancement of the magneto-optical response is observed in the photon energy regime near the localized surface plasmon resonance. A large MO enhancement, over 60% compared to the reference Ni80Fe20, takes place in Ni80Fe20–Au NPs. Optical constants extracted from spectroscopic ellipsometry measurements reveal a strong modification of the complex refractive index values (n, k) owing to the excitation of localized surface plasmons in Au nanoparticles. A close correlation of the MO response to the complex refractive indices (n, k) is found, in which the MO enhancement is accompanied by increasing reflectivity.
Gaihre, Babita,Aryal, Santosh,Barakat, Nasser A.M.,Kim, Hak Y. Elsevier S.A. 2008 Materials Science and Engineering C Vol. No.
<P><B>Abstract</B></P><P>Inspired by the structural similarity of gelatin (and collagen) linked to a mineral phase based on Ca-phosphates compounds with natural bone and increasing application of magnetic iron oxides in hyperthermia, gelatin coated iron oxide (GIO) was synthesized and hydroxyapatite (HAp) crystal nucleation and growth in the nanoparticles was explored. A series of GIO/HAp nanocomposites with various amount of GIO were synthesized by co-precipitation technique using calcium hydroxide and phosphoric acid as precursor. Various physico-chemical analysis showed that the HAp crystal nucleation and growth occurred at acidic group of gelatin, while magnetic iron oxide nanoparticles (< 8nm) were bound to the amide groups of the gelatin chain. Moreover, the growth of HAp nanocrystals in aq. GIO solution was highly influenced by the GIO contents in the solution. The mineralized composite with magnetic properties could have great scope in biomedical field as a thermoseed to kill the cancerous cell in bone side by side for the bone reinforcement.</P>
Park, J.,Aryal, M.,Vykhodtseva, N.,Zhang, Y.Z.,McDannold, N. Elsevier Science Publishers 2017 Journal of controlled release Vol.250 No.-
<P>Drug delivery in brain tumors is challenging because of the presence of blood-brain barrier (BBB) and the blood-tumor barrier (BTB). Focused ultrasound (FUS) combined with microbubbles can enhance the permeability of the BTB in brain tumors, as well as disrupting the BBB in the surrounding tissue. In this study, dynamic contrast-enhancedMagnetic Resonance Imaging (DCE-MRI) was used to characterize FUS-induced permeability changes in a rat glioma model and in the normal brain and to investigate the relationship between these changes and the resulting concentration of the chemotherapy agent doxorubicin (DOX). 9L gliosarcoma cells were implanted in both hemispheres in male rats. At day 10-12 after implantation, FUS-induced BTB disruption using 690 kHz ultrasound and Definity microbubbles was performed in one of the tumors and in a normal brain region in each animal. After FUS, DOX was administered at a dose of 5.67mg/kg. The resulting DOX concentration was measured via fluorometry at 1 or 24 h after FUS. The transfer coefficient K-trans describing extravasation of the MRI contrast agent Gd-DTPA was significantly increased in both the sonicated tumors and in the normal brain tissue (P < 0.001) between the two DCE-MRI acquisitions obtained before and after FUS, while no significant difference was found in the controls (non-sonicated tumor/normal brain tissue). DOX concentrations were also significantly larger than controls in both the sonicated tumors and in the normal tissue volumes at 1 and 24 h after sonication. The DOX concentrations were significantly larger (P < 0.01) in the control tumors harvested 1 h after FUS than in those harvested at 24 h, when the tumor concentrations were not significantly different than in the non-sonicated normal brain. In contrast, there was no significant difference in the DOX concentrations between the tumors harvested at 1 and 24 h after FUS or in the concentrations measured in the brain at these time points. The transfer coefficient Ktrans for Gd-DTPA and the drug concentrations showed a good linear correlation (R-2-0.56). Overall, these data suggest that FUS and microbubbles can not only increase DOX delivery across the BBB and BTB, but that it is retained in the tissue at significantly enhanced levels for at least 24 h. Such enhanced retention may increase the potency of this chemotherapy agent and allow for reduced systemic doses. Furthermore, MRI-based estimates of Gd-DTPA transport across these barriers might be useful to estimate local DOX concentrations in the tumor and in the surrounding normal tissue. (C) 2016 Elsevier B.V. All rights reserved.</P>
Trends of Smokeless Tobacco use among Adults (Aged 15-49 Years) in Bangladesh, India and Nepal
Sinha, Dhirendra N,Rizwan, SA,Aryal, Krishna K,Karki, Khem B,Zaman, Mostafa M,Gupta, Prakash C Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.15
Background: Smokeless tobacco (SLT) has long been realized as an important component of the fight for global tobacco control. It still remains a major problem in countries like India, Bangladesh and Nepal. The objective of this study was to estimate the trends of SLT use in three countries of the SEARO WHO office. Materials and Methods: We used data from national surveys in three countries (Bangladesh, India and Nepal) to estimate trends in prevalence of current SLT use. All available nationally representative data sources were used. Estimates were weighted, age standardized and given along with 95% confidence intervals. Significance of linear trend in prevalence over time was tested using the Cochrane-Armitage test for trend. A p value of less than 0.05 was considered statistically significant. Results: We identified three surveys for Bangladesh, three for India and four for Nepal that met the selection criteria (such as Demographic and Health Surveys, WHO-STEPwise approach to Surveillance and Global Adult Tobacco Surveys). A significantly increasing trend was noticed in the prevalence of current SLT use among Bangladeshi men (20.2% to 23%, p=0.03). In India, a similar significantly increasing trend was seen among men (27.1% to 33.4%, p<0.001) and women (10.1% to 15.7%, p<0.001). In Nepal, there was a no significant trend among both men (39.1% to 31.6%, p=0.11) and women (5.6% to 4.7%, p=0.49). Conclusions: In the study countries SLT use has remained at alarmingly high levels. Usage trends do not show any signs of decline in spite of control efforts. Tobacco control measures should focus more on controlling SLT use.
Sheikh, F.A.,Barakat, N.A.M.,Kim, B.S.,Aryal, S.,Khil, M.S.,Kim, H.Y. Elsevier 2009 Materials Science and Engineering C Vol.29 No.3
In the present study, spherical nanoparticles (NPs) containing polyhedral oligosilsesquioxane (POSS) as an inner hydrophobic core and poly(vinyl alcohol) PVA as a hydrophilic outer shell were prepared by dialysis approach. Preparation of amphiphilic POSS-grafted-PVA co-polymer was characterized by <SUP>1</SUP>H NMR and FT-IR. The results indicated urethane linkage between monoisocyanate group of POSS macromer and the hydroxyl groups of PVA. The dynamic light scattering (DLS) and electrophoretic light scattering (ELS) of the NPs revealed that they have an average hydrodynamic diameter and negative zeta (ζ)-potential of 215 nm and -161 mV, respectively. Atomic force microscopy (AFM) and bio-transmission electron microscope (BIO-TEM) have shown unagglomerated NPs within a diameter range of 60-90 nm. The prepared NPs were investigated to improve the control release of anticancer drug; paclitaxel as a model drug. Due to drug loading, the hydrodynamic diameter and negative zeta (ζ)-potential have changed to 325 nm and -14 mV, respectively. In addition, in-vitro drug release experiments were conducted; the obtained results explicated continuous release for over 40 days. However, in case of using pure drug only, the drug completely released within 1 h.
S. C. Kang,H. J. Kim,J. Y. Choi,G. S. Kim,Pabitra Aryal,Arshad Khan,S. J. Kang,J. Kaewkhao,J. M. PARK,MinJeong Kim 한국물리학회 2018 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.73 No.8
Glass scintillators can be doped with different elements to improve their luminescence properties. In this study, we present 0.5 wt% Ce3+-doped (58x)SiO2-4MgO-18Al2O3-20Li2O and (58x)SiO2- 4MgO-18Al2O3-20LiF glass scintillators. We used a pulsed laser to measure the laser-induced emission spectrum and the decay time with decreasing temperature from 300 K to 10 K. The light intensity of both glass samples increased with decreasing temperature from 300 K to 10 K. Additionally, the two glass samples exhibited a fast decay time of approximately 25 ns. In the photo-induced spectrum, an excitation peak at 312 nm and two emission peaks, at 370 nm and 700 nm, were observed in both the glass samples. The X-ray-induced emission intensity of former is approximately six times higher than that of latter, and only former glass sample exhibits a proton-induced emission spectrum.