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排序方式: 共有1801条查询结果,搜索用时 15 毫秒
41.
Balaji Bharatwaj Radovan Dimovski Denise S. Conti Sandro R. P. da Rocha 《The AAPS journal》2014,16(3):522-538
The purpose of this study was to (a) Determine the cellular transport and uptake of amine-terminated generation 3 (G3) poly(amido amine) (PAMAM) dendrimers across an in vitro model of the pulmonary epithelium, and the ability to modulate their transport by forming nanoblends of the dendrimers with biodegradable solid polymeric nanoparticles (NPs) and (b) to formulate dendrimer nanocarriers in portable oral inhalation devices and evaluate their aerosol characteristics. To that end, fluorescein isothiocyanate (FITC)-labeled G3 PAMAM dendrimer nanocarriers (DNCs) were synthesized, and also encapsulated within poly lactide-co-glycolide nanoparticles (NPs). Transport and uptake of both DNCs encapsulated within NPs (nanoblends) and unencapsulated DNCs were tracked across polarized monolayers of airway epithelial cells, Calu-3. DNCs were also formulated as core-shell microparticles in pressurized metered-dose inhalers (pMDIs) and their aerodynamic properties evaluated by Andersen cascade impaction. The apparent permeability of DNCs across the airway epithelial model was similar to that of a paracellular marker of comparable molar mass—order of 10−7 cm s−1. The transport and cellular internalization of the DNCs can be modulated by formulating them as nanoblends. The transport of the DNCs across the lung epithelium was completely suppressed within the time of the experiment (5 h) when formulated as blends. The encapsulation also prevents saturation of the cellular internalization profile. Nanoblending may be a potential strategy to modulate the rate of transport and cellular uptake of DNCs, and thus be used as a design strategy to achieve enhanced local or systemic drug delivery.
Electronic supplementary material
The online version of this article (doi:10.1208/s12248-014-9588-5) contains supplementary material, which is available to authorized users.KEY WORDS: Calu-3, dendrimers, nanoparticles, nanoblends, oral inhalation, pressurized metered-dose inhalers, transport modulation 相似文献42.
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44.
Liangling Sun Balaji Devakumar Jia Liang Bin Li Shaoying Wang Qi Sun Heng Guo Xiaoyong Huang 《RSC advances》2018,8(56):31835
In this paper, we reported on the high-efficiency and thermally-stable La2LiSbO6:Mn4+,Mg2+ (LLS:Mn4+,Mg2+) far-red emitting phosphors. Under 338 nm excitation, the composition-optimized LLS:0.3%Mn4+,1.6%Mg2+ phosphors which were made up of [SbO6], [LiO6], and [LaO8] polyhedrons, showed intense far-red emissions peaking at 712 nm (2Eg → 4A2g transition) with internal quantum efficiency as high as 92%. The LLS:0.3%Mn4+,1.6%Mg2+ phosphors also exhibited high thermal stability, and the emission intensity at 423 K only reduced by 42% compared with its initial value at 303 K. The far-red light-emitting device has also been made by using the LLS:0.3%Mn4+,1.6%Mg2+ phosphors and a 365 nm emitting InGaN chip, which can emit far-red light that is visible to the naked eye. Importantly, the emission spectrum of the LLS:0.3%Mn4+,1.6%Mg2+ phosphors can match well with the absorption spectrum of phytochrome PFR, indicating the potential of these phosphors to be used in plant growth light-emitting diodes.Double perovskite La2LiSbO6:Mn4+,Mg2+ far-red emitting phosphors with internal quantum efficiency as high as 92% and good thermal stability were developed for plant growth LEDs. 相似文献
45.
Liangling Sun Jia Liang Balaji Devakumar Qi Sun Shaoying Wang Bin Li Xiaoyong Huang 《RSC advances》2018,8(61):35187
Mn4+-activated SrLaMgSbO6 far-red emitting phosphors with double perovskite structure were prepared by traditional solid-state reaction. The research on the crystal structure of the SrLaMgSbO6:0.8%Mn4+ (SLMS:0.8%Mn4+) phosphors showed that the as-prepared sample was made up of two polyhedrons, [SbO6] and [MgO6]. Under the excitation of 333 nm, the SLMS:0.8%Mn4+ phosphors exhibited an intense far-red emission in the 625–800 nm wavelength range with CIE chromaticity coordinates of (0.733, 0.268), which could match well with the absorption spectrum of phytochrome PFR. The optimal concentration of Mn4+ ions in the SLMS:Mn4+ phosphors was 0.8 mol%. Importantly, the as-prepared SLMS:0.8%Mn4+ phosphors had an internal quantum efficiency of 35%. The thermal stability of SLMS:0.8%Mn4+ phosphors was also investigated, and the activation energy was found to be 0.3 eV. Thus, the Mn4+-activated SLMS phosphors have great potential to serve as far-red emitting phosphors in indoor plant growth lighting.Novel far-red emitting double perovskite SrLaMgSbO6:Mn4+ phosphors were prepared and their photoluminescence properties were studied for applications in indoor plant growth lighting. 相似文献
46.
Akhand Pratap Singh Rachna Singh Sumit Singh Verma Vipin Rai Catherine H. Kaschula Pralay Maiti Subash Chandra Gupta 《Medicinal research reviews》2019,39(5):1851-1891
Resveratrol is a polyphenolic nutraceutical that exhibits pleiotropic activities in human subjects. The efficacy, safety, and pharmacokinetics of resveratrol have been documented in over 244 clinical trials, with an additional 27 clinical trials currently ongoing. Resveretrol is reported to potentially improve the therapeutic outcome in patients suffering from diabetes mellitus, obesity, colorectal cancer, breast cancer, multiple myeloma, metabolic syndrome, hypertension, Alzheimer's disease, stroke, cardiovascular diseases, kidney diseases, inflammatory diseases, and rhinopharyngitis. The polyphenol is reported to be safe at doses up to 5 g/d, when used either alone or as a combination therapy. The molecular basis for the pleiotropic activities of resveratrol are based on its ability to modulate multiple cell signaling molecules such as cytokines, caspases, matrix metalloproteinases, Wnt, nuclear factor-κB, Notch, 5′-AMP-activated protein kinase, intercellular adhesion molecule, vascular cell adhesion molecule, sirtuin type 1, peroxisome proliferator-activated receptor-γ coactivator 1α, insulin-like growth factor 1, insulin-like growth factor-binding protein 3, Ras association domain family 1α, pAkt, vascular endothelial growth factor, cyclooxygenase 2, nuclear factor erythroid 2 like 2, and Kelch-like ECH–associated protein 1. Although the clinical utility of resveratrol is well documented, the rapid metabolism and poor bioavailability have limited its therapeutic use. In this regard, the recently produced micronized resveratrol formulation called SRT501, shows promise. This review discusses the currently available clinical data on resveratrol in the prevention, management, and treatment of various diseases and disorders. Based on the current evidence, the potential utility of this molecule in the clinic is discussed. 相似文献
47.
Balaji S 《Current treatment options in cardiovascular medicine》2001,3(5):385-392
Opinion statement
相似文献
– | The cardiac rhythm can be very labile in the early postoperative period, neces-sitating a high degree of vigilance. |
– | Bradycardia may be due to sinus node dysfunction or varying degrees of atrio-ventricular block, both of which are usually due to surgical trauma. Temporary pacing, using implanted temporary pacing wires, should be readily available. Most often, bradycardias are transient. Patients who fail to recover an adequate sinus rhythm or atrioventricular conduction within 7 to 10 days should be treated with a pacemaker. |
– | Supraventricular tachycardia, ventricular tachycardia, and junctional ectopic tachycardia are the major tachyarrhythmias of the early postoperative period. Establishing the diagnosis may require electrocardiography, atrial electrocar-diograph recordings, and the use of intravenous adenosine. The management options for patients with tachyarrhythmias include vagal maneuvers, hypo-thermia, pacing, drug therapy, catheter ablation, direct-current cardioversion, and adjuvant measures. |
– | Electrolytes and acid-based balance should be checked in all patients with an arrhythmia and optimized if necessary. |
48.
Seshadri Balaji Ankana Daga David J. Bradley Susan P. Etheridge Ian H. Law Anjan S. Batra Shubayan Sanatani Anoop K. Singh Kelly K. Gajewski Sabrina Tsao Harinder R. Singh Svjetlana Tisma-Dupanovic Shigeru Tateno Motoki Takamuro Hiromichi Nakajima Jolien W. Roos-Hesselink Maully Shah 《The Journal of thoracic and cardiovascular surgery》2014
49.