Next Issue
Volume 4, September
Previous Issue
Volume 4, March
 
 

Pharmaceutics, Volume 4, Issue 2 (June 2012) – 4 articles , Pages 252-333

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.
Order results
Result details
Section
Select all
Export citation of selected articles as:

Research

Jump to: Other

722 KiB  
Article
Impact of Molecular Weight on Lymphatic Drainage of a Biopolymer-Based Imaging Agent
by Taryn R. Bagby, Shuang Cai, Shaofeng Duan, Sharadvi Thati, Daniel J. Aires and Laird Forrest
Pharmaceutics 2012, 4(2), 276-295; https://doi.org/10.3390/pharmaceutics4020276 - 23 May 2012
Cited by 31 | Viewed by 9785
Abstract
New lymphatic imaging technologies are needed to better assess immune function and cancer progression and treatment. Lymphatic uptake depends mainly on particle size (10–100 nm) and charge. The size of carriers for imaging and drug delivery can be optimized to maximize lymphatic uptake, [...] Read more.
New lymphatic imaging technologies are needed to better assess immune function and cancer progression and treatment. Lymphatic uptake depends mainly on particle size (10–100 nm) and charge. The size of carriers for imaging and drug delivery can be optimized to maximize lymphatic uptake, localize chemotherapy to lymphatic metastases, and enable visualization of treatment deposition. Toward this end, female BALB/c mice were injected subcutaneously in the hind footpad or forearm with a series of six different molecular weight hyaluronan (HA) near-infrared dye (HA-IR820) conjugates (ca. 5–200 nm). Mice were imaged using whole body fluorescent imaging over two weeks. HA-IR820 fluorescence was clearly visualized in the draining lymphatic capillaries, and in the popliteal and iliac or axillary lymph nodes. The 74-kDa HA-IR820 had the largest lymph node area-under-the-curve. In contrast to prior reports, mice bearing limb tumors exhibited three-fold longer retention of 74-kDa HA-IR820 in the popliteal node compared to mice without tumors. HA conjugate kinetics and disposition can be specifically tailored by altering their molecular weight. The specific lymphatic uptake and increased nodal retention of HA conjugates indicate significant potential for development as a natural biopolymer for intralymphatic drug delivery and imaging. Full article
(This article belongs to the Special Issue Drug Delivery Using Nanotechnology)
Show Figures

Figure 1

860 KiB  
Article
Hydrotalcite Intercalated siRNA: Computational Characterization of the Interlayer Environment
by Hong Zhang, Defang Ouyang, Vinuthaa Murthy, Yunyi Wong, Zhiping Xu and Sean C. Smith
Pharmaceutics 2012, 4(2), 296-313; https://doi.org/10.3390/pharmaceutics4020296 - 07 Jun 2012
Cited by 7 | Viewed by 7816
Abstract
Using molecular dynamics (MD) simulations, we explore the structural and dynamical properties of siRNA within the intercalated environment of a Mg:Al 2:1 Layered Double Hydroxide (LDH) nanoparticle. An ab initio force field (Condensed-phase Optimized Molecular Potentials for Atomistic Simulation Studies: COMPASS) [...] Read more.
Using molecular dynamics (MD) simulations, we explore the structural and dynamical properties of siRNA within the intercalated environment of a Mg:Al 2:1 Layered Double Hydroxide (LDH) nanoparticle. An ab initio force field (Condensed-phase Optimized Molecular Potentials for Atomistic Simulation Studies: COMPASS) is used for the MD simulations of the hybrid organic-inorganic systems. The structure, arrangement, mobility, close contacts and hydrogen bonds associated with the intercalated RNA are examined and contrasted with those of the isolated RNA. Computed powder X-ray diffraction patterns are also compared with related LDH-DNA experiments. As a method of probing whether the intercalated environment approximates the crystalline or rather the aqueous state, we explore the stability of the principle parameters (e.g., the major groove width) that differentiate both A- and A'- crystalline forms of siRNA and contrast this with recent findings for the same siRNA simulated in water. We find the crystalline forms remain structurally distinct when intercalated, whereas this is not the case in water. Implications for the stability of hybrid LDH-RNA systems are discussed. Full article
(This article belongs to the Special Issue Gene Therapy)
Show Figures

Graphical abstract

328 KiB  
Article
Expression Profile of Drug and Nutrient Absorption Related Genes in Madin-Darby Canine Kidney (MDCK) Cells Grown under Differentiation Conditions
by Yong Quan, Yisheng Jin, Teresa N. Faria, Charles A. Tilford, Aiqing He, Doris A. Wall, Ronald L. Smith and Balvinder S. Vig
Pharmaceutics 2012, 4(2), 314-333; https://doi.org/10.3390/pharmaceutics4020314 - 18 Jun 2012
Cited by 22 | Viewed by 7450
Abstract
The expression levels of genes involved in drug and nutrient absorption were evaluated in the Madin-Darby Canine Kidney (MDCK) in vitro drug absorption model. MDCK cells were grown on plastic surfaces (for 3 days) or on Transwell® membranes (for 3, 5, 7, [...] Read more.
The expression levels of genes involved in drug and nutrient absorption were evaluated in the Madin-Darby Canine Kidney (MDCK) in vitro drug absorption model. MDCK cells were grown on plastic surfaces (for 3 days) or on Transwell® membranes (for 3, 5, 7, and 9 days). The expression profile of genes including ABC transporters, SLC transporters, and cytochrome P450 (CYP) enzymes was determined using the Affymetrix® Canine GeneChip®. Expression of genes whose probe sets passed a stringent confirmation process was examined. Expression of a few transporter (MDR1, PEPT1 and PEPT2) genes in MDCK cells was confirmed by RT-PCR. The overall gene expression profile was strongly influenced by the type of support the cells were grown on. After 3 days of growth, expression of 28% of the genes was statistically different (1.5-fold cutoff, p < 0.05) between the cells grown on plastic and Transwell® membranes. When cells were differentiated on Transwell® membranes, large changes in gene expression profile were observed during the early stages, which then stabilized after 5–7 days. Only a small number of genes encoding drug absorption related SLC, ABC, and CYP were detected in MDCK cells, and most of them exhibited low hybridization signals. Results from this study provide valuable reference information on endogenous gene expression in MDCK cells that could assist in design of drug-transporter and/or drug-enzyme interaction studies, and help interpret the contributions of various transporters and metabolic enzymes in studies with MDCK cells. Full article
(This article belongs to the Special Issue Oral and Buccal Drug Delivery)
Show Figures

Graphical abstract

Other

Jump to: Research

687 KiB  
Other
Breakdown of the Blood-Ocular Barrier as a Strategy for the Systemic Use of Nanosystems
by Marcelo L. Occhiutto, Fatima R. Freitas, Raul C. Maranhao and Vital P. Costa
Pharmaceutics 2012, 4(2), 252-275; https://doi.org/10.3390/pharmaceutics4020252 - 14 May 2012
Cited by 63 | Viewed by 12882
Abstract
Several drug delivery systems have been proposed to overcome physiological barriers, improving ocular bioavailability. Systemic routes are seldom used due to the blood-ocular barrier. Novel drug delivery systems based on nanotechnology techniques have been developed to overcome ocular physiological barriers. This non-systematic review [...] Read more.
Several drug delivery systems have been proposed to overcome physiological barriers, improving ocular bioavailability. Systemic routes are seldom used due to the blood-ocular barrier. Novel drug delivery systems based on nanotechnology techniques have been developed to overcome ocular physiological barriers. This non-systematic review suggests the utilization of a transitory blood-ocular breakdown to allow the access of drugs by nanotechnology drug delivery systems via the systemic route. We discuss the possible ways to cause the breakdown of the blood-ocular barrier: acute inflammation caused by intraocular surgery, induced ocular hypotony, and the use of inflammatory mediators. The suitability of use of the systemic route and its toxic effects are also discussed in this article. Full article
(This article belongs to the Special Issue Ocular Drug Delivery)
Show Figures

Figure 1

Previous Issue
Next Issue
Back to TopTop