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Pharmaceutics, Volume 10, Issue 1 (March 2018)

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Open AccessReview Evidence of Drug–Nutrient Interactions with Chronic Use of Commonly Prescribed Medications: An Update
Pharmaceutics 2018, 10(1), 36; https://doi.org/10.3390/pharmaceutics10010036
Received: 13 February 2018 / Revised: 13 March 2018 / Accepted: 16 March 2018 / Published: 20 March 2018
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Abstract
The long-term use of prescription and over-the-counter drugs can induce subclinical and clinically relevant micronutrient deficiencies, which may develop gradually over months or even years. Given the large number of medications currently available, the number of research studies examining potential drug–nutrient interactions is
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The long-term use of prescription and over-the-counter drugs can induce subclinical and clinically relevant micronutrient deficiencies, which may develop gradually over months or even years. Given the large number of medications currently available, the number of research studies examining potential drug–nutrient interactions is quite limited. A comprehensive, updated review of the potential drug–nutrient interactions with chronic use of the most often prescribed medications for commonly diagnosed conditions among the general U.S. adult population is presented. For the majority of the interactions described in this paper, more high-quality intervention trials are needed to better understand their clinical importance and potential consequences. A number of these studies have identified potential risk factors that may make certain populations more susceptible, but guidelines on how to best manage and/or prevent drug-induced nutrient inadequacies are lacking. Although widespread supplementation is not currently recommended, it is important to ensure at-risk patients reach their recommended intakes for vitamins and minerals. In conjunction with an overall healthy diet, appropriate dietary supplementation may be a practical and efficacious way to maintain or improve micronutrient status in patients at risk of deficiencies, such as those taking medications known to compromise nutritional status. The summary evidence presented in this review will help inform future research efforts and, ultimately, guide recommendations for patient care. Full article
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Open AccessArticle Orally Disintegrating Tablets Containing Melt Extruded Amorphous Solid Dispersion of Tacrolimus for Dissolution Enhancement
Pharmaceutics 2018, 10(1), 35; https://doi.org/10.3390/pharmaceutics10010035
Received: 9 February 2018 / Revised: 9 March 2018 / Accepted: 10 March 2018 / Published: 16 March 2018
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Abstract
In order to improve the aqueous solubility and dissolution of Tacrolimus (TAC), amorphous solid dispersions of TAC were prepared by hot melt extrusion with three hydrophilic polymers, Polyvinylpyrrolidone vinyl acetate (PVP VA64), Soluplus® and Hydroxypropyl Cellulose (HPC), at a drug loading of
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In order to improve the aqueous solubility and dissolution of Tacrolimus (TAC), amorphous solid dispersions of TAC were prepared by hot melt extrusion with three hydrophilic polymers, Polyvinylpyrrolidone vinyl acetate (PVP VA64), Soluplus® and Hydroxypropyl Cellulose (HPC), at a drug loading of 10% w/w. Molecular modeling was used to determine the miscibility of the drug with the carrier polymers by calculating the Hansen Solubility Parameters. Powder X-ray diffraction and differential scanning calorimetry (DSC) studies of powdered solid dispersions revealed the conversion of crystalline TAC to amorphous form. Fourier transform Infrared (FTIR) spectroscopy results indicated formation of hydrogen bond between TAC and polymers leading to stabilization of TAC in amorphous form. The extrudates were found to be stable under accelerated storage conditions for 3 months with no re-crystallization, indicating that hot melt extrusion is suitable for producing stable amorphous solid dispersions of TAC in PVP VA64, Soluplus® and HPC. Stable solid dispersions of amorphous TAC exhibited higher dissolution rate, with the solid dispersions releasing more than 80% drug in 15 min compared to the crystalline drug giving 5% drug release in two hours. These stable solid dispersions were incorporated into orally-disintegrating tablets in which the solid dispersion retained its solubility, dissolution and stability advantage. Full article
(This article belongs to the Special Issue Dissolution Enhancement of Poorly Soluble Drugs)
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Open AccessReview Surface-Modified Nanocarriers for Nose-to-Brain Delivery: From Bioadhesion to Targeting
Pharmaceutics 2018, 10(1), 34; https://doi.org/10.3390/pharmaceutics10010034
Received: 8 February 2018 / Revised: 10 March 2018 / Accepted: 12 March 2018 / Published: 15 March 2018
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Abstract
In the field of nasal drug delivery, nose-to-brain delivery is among the most fascinating applications, directly targeting the central nervous system, bypassing the blood brain barrier. Its benefits include dose lowering and direct brain distribution of potent drugs, ultimately reducing systemic side effects.
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In the field of nasal drug delivery, nose-to-brain delivery is among the most fascinating applications, directly targeting the central nervous system, bypassing the blood brain barrier. Its benefits include dose lowering and direct brain distribution of potent drugs, ultimately reducing systemic side effects. Recently, nasal administration of insulin showed promising results in clinical trials for the treatment of Alzheimer’s disease. Nanomedicines could further contribute to making nose-to-brain delivery a reality. While not disregarding the need for devices enabling a formulation deposition in the nose’s upper part, surface modification of nanomedicines appears the key strategy to optimize drug delivery from the nasal cavity to the brain. In this review, nanomedicine delivery based on particle engineering exploiting surface electrostatic charges, mucoadhesive polymers, or chemical moieties targeting the nasal epithelium will be discussed and critically evaluated in relation to nose-to-brain delivery. Full article
(This article belongs to the Special Issue Nose to Brain Delivery)
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Open AccessArticle Hyaluronic Acid Decorated Naringenin Nanoparticles: Appraisal of Chemopreventive and Curative Potential for Lung Cancer
Pharmaceutics 2018, 10(1), 33; https://doi.org/10.3390/pharmaceutics10010033
Received: 5 February 2018 / Revised: 25 February 2018 / Accepted: 5 March 2018 / Published: 12 March 2018
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Abstract
Lung carcinoma is the most common cancer in men and second in women (preceded by breast cancer) worldwide. Around 1 in 10 of all cancers diagnosed in men, lung cancer contributed to a total fraction of 20% cancer deaths. Naringenin (NAR) is well
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Lung carcinoma is the most common cancer in men and second in women (preceded by breast cancer) worldwide. Around 1 in 10 of all cancers diagnosed in men, lung cancer contributed to a total fraction of 20% cancer deaths. Naringenin (NAR) is well known for its chemopreventive properties since ancient times but lacks an appropriate delivery carrier. The objective of present study was to expand the functionality of naringenin loaded poly caprolactone (PCL) nanoparticles in terms of release, chemoprevention and therapeutics. Polymeric nanoparticles such as PCL lack target specificity; hence, surface modification was attempted using layer by layer technique (LBL) to achieve improved and desired delivery as well as target specificity. The designing of Hyaluronic acid (HA) decorated PCL nanoparticles were prepared by utilizing self-assembling LBL technique, where a polycationic layer of a polymer was used as a linker for modification between two polyanionic layers. Additionally, an attempt has been made to strengthen the therapeutic efficacy of PCL nanocarriers by active targeting and overcoming the extracellular matrix associated barriers of tumors using HA targeting cluster determinant 44 receptor (CD44). Cell cytotoxicity study on A549 cells and J774 macrophage cells depicted enhanced anticancer effect of NAR-HA@CH-PCL-NP with safe profile on macrophages. Uptake study on A549 cells advocated enhanced drug uptake by cancer cells. Cell cycle arrest analysis (A549 cell lines) demonstrated the superior cytotoxic effect and active targeting of NAR-HA@CH-PCL-NP. Further chemopreventive treatment with NAR-HA@CH-PCL-NP was found effective in tumor growth inhibitory effect against urethane-induced lung cancer in rat. In conclusion, developed formulation possesses a promising potential as a therapeutic and chemopreventive agent against urethane-induced lung carcinoma in albino wistar rats. Full article
(This article belongs to the Special Issue Nanotechnology Advances in Cancer Treatment)
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Open AccessArticle Citrate- and Succinate-Modified Carbonate Apatite Nanoparticles with Loaded Doxorubicin Exhibit Potent Anticancer Activity against Breast Cancer Cells
Pharmaceutics 2018, 10(1), 32; https://doi.org/10.3390/pharmaceutics10010032
Received: 7 February 2018 / Revised: 19 February 2018 / Accepted: 22 February 2018 / Published: 11 March 2018
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Abstract
Biodegradable inorganic apatite-based particle complex is popular for its pH-sensitivity at the endosomal acidic environment to facilitate drug release following cellular uptake. Despite being a powerful anticancer drug, doxorubicin shows severe off-target effects and therefore would need a carrier for the highest effectiveness.
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Biodegradable inorganic apatite-based particle complex is popular for its pH-sensitivity at the endosomal acidic environment to facilitate drug release following cellular uptake. Despite being a powerful anticancer drug, doxorubicin shows severe off-target effects and therefore would need a carrier for the highest effectiveness. We aimed to chemically modify carbonate apatite (CA) with Krebs cycle intermediates, such as citrate and succinate in order to control the growth of the resultant particles to more efficiently carry and transport the anticancer drug into the cancer cells. Citrate- or succinate-modified CA particles were synthesized with different concentrations of sodium citrate or sodium succinate, respectively, in the absence or presence of doxorubicin. The drug loading efficiency of the particles and their cellular uptake were observed by quantifying fluorescence intensity. The average diameter and surface charge of the particles were determined using Zetasizer. Cell viability was assessed by MTT assay. Citrate-modified carbonate apatite (CMCA) exhibited the highest (31.38%) binding affinity for doxorubicin and promoted rapid cellular uptake of the drug, leading to the half-maximal inhibitory concentration 1000 times less than that of the free drug in MCF-7 cells. Hence, CMCA nanoparticles with greater surface area enhance cytotoxicity in different breast cancer cells by enabling higher loading and more efficient cellular uptake of the drug. Full article
(This article belongs to the Special Issue Nanotechnology Advances in Cancer Treatment)
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Open AccessArticle Absolute Oral Bioavailability of Creatine Monohydrate in Rats: Debunking a Myth
Pharmaceutics 2018, 10(1), 31; https://doi.org/10.3390/pharmaceutics10010031
Received: 8 November 2017 / Revised: 13 February 2018 / Accepted: 27 February 2018 / Published: 8 March 2018
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Abstract
Creatine is an ergogenic compound used by athletes to enhance performance. Supplementation with creatine monohydrate (CM) has been suggested for musculoskeletal and neurological disorders. Until now, little is known about its pharmacokinetic profile. Our objective was to determine the oral bioavailability of CM
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Creatine is an ergogenic compound used by athletes to enhance performance. Supplementation with creatine monohydrate (CM) has been suggested for musculoskeletal and neurological disorders. Until now, little is known about its pharmacokinetic profile. Our objective was to determine the oral bioavailability of CM and the influence of dose on oral absorption. Rats were dosed orally with low dose (10 mg/kg) or high dose (70 mg/kg) 13C-labeled CM. Blood samples were removed at various time points. Muscle and brain tissue were collected at the conclusion of the study. Plasma and tissue levels of 13C-labeled creatine were determined using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Physiologically based pharmacokinetic (PBPK) models of CM were built using GastroPlus™. These models were used to predict the plasma concentration–time profiles of creatine hydrochloride (CHCL), which has improved aqueous solubility compared to CM. Absolute oral bioavailability for low dose CM was 53% while high dose CM was only 16%. The simulated Cmax of 70 mg/kg CHCL was around 35 μg/mL compared to 14 μg/mL for CM with a predicted oral bioavailability of 66% with CHCL compared to 17% with CM. Our results suggest that the oral bioavailability of CM is less than complete and subject to dose and that further examination of improved dosage formulations of creatine is warranted. Full article
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Open AccessArticle Rational Design, Synthesis and Evaluation of γ-CD-Containing Cross-Linked Polyvinyl Alcohol Hydrogel as a Prednisone Delivery Platform
Pharmaceutics 2018, 10(1), 30; https://doi.org/10.3390/pharmaceutics10010030
Received: 30 January 2018 / Revised: 1 March 2018 / Accepted: 4 March 2018 / Published: 7 March 2018
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Abstract
This study describes the in-silico rational design, synthesis and evaluation of cross-linked polyvinyl alcohol hydrogels containing γ-cyclodextrin (γ-CDHSAs) as platforms for the sustained release of prednisone (PDN). Through in-silico studies using semi-empirical quantum mechanical calculations, the effectiveness of 20 dicarboxylic acids to generate
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This study describes the in-silico rational design, synthesis and evaluation of cross-linked polyvinyl alcohol hydrogels containing γ-cyclodextrin (γ-CDHSAs) as platforms for the sustained release of prednisone (PDN). Through in-silico studies using semi-empirical quantum mechanical calculations, the effectiveness of 20 dicarboxylic acids to generate a specific cross-linked hydrogel capable of supporting different amounts of γ-cyclodextrin (γ-CD) was evaluated. According to the interaction energies calculated with the in-silico studies, the hydrogel made from PVA cross-linked with succinic acids (SA) was shown to be the best candidate for containing γ-CD. Later, molecular dynamics simulation studies were performed in order to evaluate the intermolecular interactions between PDN and three cross-linked hydrogel formulations with different proportions of γ-CD (2.44%, 4.76% and 9.1%). These three cross-linked hydrogels were synthesized and characterized. The loading and the subsequent release of PDN from the hydrogels were investigated. The in-silico and experimental results showed that the interaction between PDN and γ-CDHSA was mainly produced with the γ-CDs linked to the hydrogels. Thus, the unique structures and properties of γ-CDHSA demonstrated an interesting multiphasic profile that could be utilized as a promising drug carrier for controlled, sustained and localized release of PDN. Full article
(This article belongs to the Special Issue Smart Hydrogels for Drug Delivery)
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Open AccessArticle Prediction of Phase Behavior of Spray-Dried Amorphous Solid Dispersions: Assessment of Thermodynamic Models, Standard Screening Methods and a Novel Atomization Screening Device with Regard to Prediction Accuracy
Pharmaceutics 2018, 10(1), 29; https://doi.org/10.3390/pharmaceutics10010029
Received: 11 February 2018 / Revised: 27 February 2018 / Accepted: 2 March 2018 / Published: 7 March 2018
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Abstract
The evaluation of drug–polymer miscibility in the early phase of drug development is essential to ensure successful amorphous solid dispersion (ASD) manufacturing. This work investigates the comparison of thermodynamic models, conventional experimental screening methods (solvent casting, quench cooling), and a novel atomization screening
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The evaluation of drug–polymer miscibility in the early phase of drug development is essential to ensure successful amorphous solid dispersion (ASD) manufacturing. This work investigates the comparison of thermodynamic models, conventional experimental screening methods (solvent casting, quench cooling), and a novel atomization screening device based on their ability to predict drug–polymer miscibility, solid state properties (Tg value and width), and adequate polymer selection during the development of spray-dried amorphous solid dispersions (SDASDs). Binary ASDs of four drugs and seven polymers were produced at 20:80, 40:60, 60:40, and 80:20 (w/w). Samples were systematically analyzed using modulated differential scanning calorimetry (mDSC) and X-ray powder diffraction (XRPD). Principal component analysis (PCA) was used to qualitatively assess the predictability of screening methods with regards to SDASD development. Poor correlation was found between theoretical models and experimentally-obtained results. Additionally, the limited ability of usual screening methods to predict the miscibility of SDASDs did not guarantee the appropriate selection of lead excipient for the manufacturing of robust SDASDs. Contrary to standard approaches, our novel screening device allowed the selection of optimal polymer and drug loading and established insight into the final properties and performance of SDASDs at an early stage, therefore enabling the optimization of the scaled-up late-stage development. Full article
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Open AccessReview Ocular Drug Delivery Barriers—Role of Nanocarriers in the Treatment of Anterior Segment Ocular Diseases
Pharmaceutics 2018, 10(1), 28; https://doi.org/10.3390/pharmaceutics10010028
Received: 22 December 2017 / Revised: 12 February 2018 / Accepted: 23 February 2018 / Published: 27 February 2018
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Abstract
Ocular drug delivery is challenging due to the presence of anatomical and physiological barriers. These barriers can affect drug entry into the eye following multiple routes of administration (e.g., topical, systemic, and injectable). Topical administration in the form of eye drops is preferred
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Ocular drug delivery is challenging due to the presence of anatomical and physiological barriers. These barriers can affect drug entry into the eye following multiple routes of administration (e.g., topical, systemic, and injectable). Topical administration in the form of eye drops is preferred for treating anterior segment diseases, as it is convenient and provides local delivery of drugs. Major concerns with topical delivery include poor drug absorption and low bioavailability. To improve the bioavailability of topically administered drugs, novel drug delivery systems are being investigated. Nanocarrier delivery systems demonstrate enhanced drug permeation and prolonged drug release. This review provides an overview of ocular barriers to anterior segment delivery, along with ways to overcome these barriers using nanocarrier systems. The disposition of nanocarriers following topical administration, their safety, toxicity and clinical trials involving nanocarrier systems are also discussed. Full article
(This article belongs to the Special Issue Advanced Ocular Drug Delivery)
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Open AccessArticle In Vitro Evaluation of Sunscreen Safety: Effects of the Vehicle and Repeated Applications on Skin Permeation from Topical Formulations
Pharmaceutics 2018, 10(1), 27; https://doi.org/10.3390/pharmaceutics10010027
Received: 16 December 2017 / Revised: 16 February 2018 / Accepted: 24 February 2018 / Published: 27 February 2018
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Abstract
The evaluation of UV-filter in vitro percutaneous absorption allows the estimation of the systemic exposure dose (SED) and the margin of safety (MoS) of sunscreen products. As both the vehicle and pattern of application may affect sunscreen safety and efficacy, we evaluated in
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The evaluation of UV-filter in vitro percutaneous absorption allows the estimation of the systemic exposure dose (SED) and the margin of safety (MoS) of sunscreen products. As both the vehicle and pattern of application may affect sunscreen safety and efficacy, we evaluated in vitro release and skin permeation of two widely used UV-filters, octylmethoxycinnamate (OMC) and butylmethoxydibenzoylmethane (BMBM) from topical formulations with different features (oil in water (O/W) emulsions with different viscosity, water in oil (W/O) emulsion, oils with different lipophilicity). To mimic in-use conditions, we carried out experiments repeating sunscreen application on the skin surface for three consecutive days. BMBM release from all these vehicles was very low, thus leading to poor skin permeation. The vehicle composition significantly affected OMC release and skin permeation, and slight increases of OMC permeation were observed after repeated applications. From skin permeation data, SED and MoS values of BMBM and OMC were calculated for all the investigated formulations after a single application and repeated applications. While MoS values of BMBM were always well beyond the accepted safety limit, the safety of sunscreen formulations containing OMC may depend on the vehicle composition and the application pattern. Full article
(This article belongs to the Special Issue Penetration Enhancement of Topical Formulations)
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Open AccessArticle Design, Optimization and Characterization of a Transfersomal Gel Using Miconazole Nitrate for the Treatment of Candida Skin Infections
Pharmaceutics 2018, 10(1), 26; https://doi.org/10.3390/pharmaceutics10010026
Received: 19 January 2018 / Revised: 17 February 2018 / Accepted: 20 February 2018 / Published: 23 February 2018
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Abstract
Miconazole nitrate (MIC) is an antifungal drug used for treatment of superficial fungal infections. However, it has low skin permeability. Hence, the objective of this study was to prepare miconazole nitrate using Transfersomes to overcome the barrier function of the skin. MIC Transfersomes
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Miconazole nitrate (MIC) is an antifungal drug used for treatment of superficial fungal infections. However, it has low skin permeability. Hence, the objective of this study was to prepare miconazole nitrate using Transfersomes to overcome the barrier function of the skin. MIC Transfersomes were prepared using a thin lipid film hydration technique. The prepared Transfersomes were evaluated with respect to entrapment efficiency (EE%), particle size, and quantity of in vitro drug released to obtain an optimized formulation. The optimized formulation of MIC Transfersomes was incorporated into a Carbapol 934 gel base which was evaluated in comparison with a marketed product (Daktarin® cream 2%) for drug content, pH, spreadability, viscosity, in vitro permeation, and in vitro and in vivo antifungal activity. The prepared MIC Transfersomes had a high EE% ranging from (67.98 ± 0.66%) to (91.47 ± 1.85%), with small particle sizes ranging from (63.5 ± 0.604 nm) to (84.5 ± 0.684 nm). The in vitro release study suggested that there was an inverse relationship between EE% and in vitro release. The kinetic analysis of all release profiles was found to follow Higuchi’s diffusion model. All independent variables had a significant effect on the dependent variables (p-values < 0.05). The prepared MIC transfersomal gel showed higher antifungal activity than Daktarin® cream 2%. Therefore, miconazole nitrate in the form of Transfersomes has the ability to penetrate the skin, overcoming the stratum corneum barrier. Full article
(This article belongs to the Special Issue Lipid-Based Dosage Form)
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Open AccessArticle Pharmacokinetics and Scintigraphic Imaging of the Hypoxia-Imaging Agent [123I]IAZA in Healthy Adults Following Exercise-Based Cardiac Stress
Pharmaceutics 2018, 10(1), 25; https://doi.org/10.3390/pharmaceutics10010025
Received: 15 January 2018 / Revised: 16 February 2018 / Accepted: 16 February 2018 / Published: 22 February 2018
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Abstract
The objective of this work is to evaluate the potential effect of cardiac stress exercise on the accumulation of [123I]IAZA, a radiopharmaceutical used to image focal tissue hypoxia, in otherwise normal myocardium in healthy volunteers, and to determine the impact of
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The objective of this work is to evaluate the potential effect of cardiac stress exercise on the accumulation of [123I]IAZA, a radiopharmaceutical used to image focal tissue hypoxia, in otherwise normal myocardium in healthy volunteers, and to determine the impact of exercise on [123I]IAZA pharmacokinetics. The underlying goal is to establish a rational basis and a baseline for studies of focal myocardial hypoxia in cardiac patients using [123I]IAZA. Three healthy male volunteers ran the ‘Bruce’ treadmill protocol, a clinically-accepted protocol designed to expose myocardial ischemia in patients. The ‘Bruce’ criterion heart rate is 85% of [220–age]. Approximately one minute before reaching this level, [123I]IAZA (5.0 mCi/0.85 mg) was administered as a slow (1–3 min) single intravenous (i.v.) injection via an indwelling venous catheter. The volunteer continued running for an additional 1 min before being transferred to a gamma camera. Serum samples were collected from the arm contralateral to the administration site at pre-determined intervals from 1 min to 45 h post injection and were analyzed by radio HPLC. Pharmacokinetic (PK) parameters were derived for [123I]IAZA and total radioactivity (total[123I]) using compartmental and noncompartmental analyses. Whole-body planar scintigraphic images were acquired from 0.75 to 24 h after dosing. PK data and scintigraphic images were compared to previously published [123I]IAZA data from healthy volunteers rest. Following exercise stress, both [123I]IAZA and total[123I] exhibited bi-exponential decline profiles, with rapid distribution phases [half-lives (t1/2α) of 1.2 and 1.4 min, respectively], followed by slower elimination phases [t1/2β of 195 and 290 min, respectively]. Total body clearance (CLTB) and the steady state volume of distribution (Vss) were 0.647 L/kg and 185 mL/min, respectively, for [123I]IAZA and 0.785 L/kg and 135 mL/min, respectively, for total[123I]. The t1/2β, CLTB and Vss values were comparable to those reported previously for rested volunteers. The t1/2α was approximately 4-fold shorter for [123I]IAZA and approximately 3-fold shorter for total[123I] under exercise relative to rested subjects. The heart region was visualized in early whole body scintigraphic images, but later images showed no accumulated radioactivity in this region, and no differences from images reported for rested volunteers were apparent. Minimal uptake of radiotracer in myocardium and skeletal muscle was consistent with uptake in non-stressed myocardium. Whole-body scintigrams for [123I]IAZA in exercise-stressed healthy volunteers were indistinguishable from images of non-exercised volunteers. There was no evidence of hypoxia-dependent binding in exercised but otherwise healthy myocardium, supporting the conclusion that exercise stress at Bruce protocol intensity does not induce measurable myocardial hypoxia. Effects of exercise on PK parameters were minimal; specifically, the t1/2α was shortened, reflecting increased cardiac output associated with exercise. It is concluded that because [123I]IAZA was not metabolically bound in exercise-stressed myocardium, a stress test will not create elevated myocardial background that would mask regions of myocardial perfusion deficiency. [123I]IAZA would therefore be suitable for the detection of viable, hypoxic myocardium in patients undergoing stress-test-based diagnosis. Full article
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Open AccessArticle Epinephrine in Anaphylaxis: Preclinical Study of Pharmacokinetics after Sublingual Administration of Taste-Masked Tablets for Potential Pediatric Use
Pharmaceutics 2018, 10(1), 24; https://doi.org/10.3390/pharmaceutics10010024
Received: 22 November 2017 / Revised: 19 December 2017 / Accepted: 12 January 2018 / Published: 11 February 2018
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Abstract
Epinephrine is a life-saving treatment in anaphylaxis. In community settings, a first-aid dose of epinephrine is injected from an auto-injector (EAI). Needle phobia highly contributes to EAI underuse, leading to fatalities—especially in children. A novel rapidly-disintegrating sublingual tablet (RDST) of epinephrine was developed
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Epinephrine is a life-saving treatment in anaphylaxis. In community settings, a first-aid dose of epinephrine is injected from an auto-injector (EAI). Needle phobia highly contributes to EAI underuse, leading to fatalities—especially in children. A novel rapidly-disintegrating sublingual tablet (RDST) of epinephrine was developed in our laboratory as a potential alternative dosage form. The aim of this study was to evaluate the sublingual bioavailability of epinephrine 30 mg as a potential pediatric dose incorporated in our novel taste-masked RDST in comparison with intramuscular (IM) epinephrine 0.15 mg from EAI, the recommended and only available dosage form for children in community settings. We studied the rate and extent of epinephrine absorption in our validated rabbit model (n = 5) using a cross-over design. The positive control was IM epinephrine 0.15 mg from an EpiPen Jr®. The negative control was a placebo RDST. Tablets were placed under the tongue for 2 min. Blood samples were collected at frequent intervals and epinephrine concentrations were measured using HPLC with electrochemical detection. The mean ± SEM maximum plasma concentration (Cmax) of 16.7 ± 1.9 ng/mL at peak time (Tmax) of 21 min after sublingual epinephrine 30 mg did not differ significantly (p > 0.05) from the Cmax of 18.8 ± 1.9 ng/mL at a Tmax of 36 min after IM epinephrine 0.15 mg. The Cmax of both doses was significantly higher than the Cmax of 7.5 ± 1.7 ng/mL of endogenous epinephrine after placebo. These taste-masked RDSTs containing a 30 mg dose of epinephrine have the potential to be used as an easy-to-carry, palatable, non-invasive treatment for anaphylactic episodes for children in community settings. Full article
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Open AccessArticle Chitosan Loaded into a Hydrogel Delivery System as a Strategy to Treat Vaginal Co-Infection
Pharmaceutics 2018, 10(1), 23; https://doi.org/10.3390/pharmaceutics10010023
Received: 22 December 2017 / Revised: 27 January 2018 / Accepted: 1 February 2018 / Published: 3 February 2018
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Abstract
Polymeric hydrogels are common dosage forms designed for the topical administration of antimicrobial drugs to treat vaginal infections. One of the major advantages of using chitosan in these formulations is related to the intrinsic and broad antimicrobial activity exerted on bacteria and fungi
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Polymeric hydrogels are common dosage forms designed for the topical administration of antimicrobial drugs to treat vaginal infections. One of the major advantages of using chitosan in these formulations is related to the intrinsic and broad antimicrobial activity exerted on bacteria and fungi by this natural polymer. Most vaginal yeast infections are caused by the pathogenic fungus Candida albicans. However, despite the anti-Candida activity towards and strains susceptibility to low molecular weight chitosan being documented, no information is available regarding the antimicrobial efficacy of mixed hydrogels in which chitosan is dispersed in a polymeric matrix. Therefore, the aim of the study is to evaluate the anti-Candida activity against eight different albicans and non-albicans strains of a mixed hydroxypropyl methylcellulose (HPMC)/chitosan hydrogel. Importantly, chitosan was dispersed in HPMC matrix either assembled in nanoparticles or in a monomolecular state to eventually correlate any variation in terms of rheological and mucoadhesive properties, as well as anti-Candida activity, with the chitosan form. Hydrogels containing 1% w/w chitosan, either as free polymer chain or assembled in nanoparticles, showed an improved mucoadhesiveness and an anti-Candida effect against all tested albicans and non-albicans strains. Overall, the results demonstrate the feasibility of preparing HPMC/CS mixed hydrogels intended for the prevention and treatment of Candida infections after vaginal administration. Full article
(This article belongs to the Special Issue Chitosan Biomedical Applications: Opportunities and Challenges)
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Open AccessArticle Feasibility of Using Gluconolactone, Trehalose and Hydroxy-Propyl Gamma Cyclodextrin to Enhance Bendroflumethiazide Dissolution Using Lyophilisation and Physical Mixing Techniques
Pharmaceutics 2018, 10(1), 22; https://doi.org/10.3390/pharmaceutics10010022
Received: 29 November 2017 / Revised: 22 January 2018 / Accepted: 24 January 2018 / Published: 1 February 2018
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Abstract
Purpose: Hydrophobic drugs are facing a major challenge in dissolution rate enhancement and solubility in aqueous solutions; therefore, a variety of methods have been used to improve dissolution rate and/or solubility of bendroflumethiazide as a model hydrophobic drug. Methods: In this study, two
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Purpose: Hydrophobic drugs are facing a major challenge in dissolution rate enhancement and solubility in aqueous solutions; therefore, a variety of methods have been used to improve dissolution rate and/or solubility of bendroflumethiazide as a model hydrophobic drug. Methods: In this study, two main methods (physical mixing and lyophilisation) were used with gluconolactone, hydroxyl propyl γ-ccyclodextrin, and trehalose to explore this challenge. Bendroflumethiazide, practically insoluble in water, was mixed with one of the three excipients gluconolactone, hydroxyl propyl γ-cyclodextrin, and trehalose in three different ratios 1:1, 1:2, 1:5. To the best of our knowledge, the dissolution of the drug has not been previously enhanced by using either these methods or any of the used excipients. Samples containing drug and each of the excipients were characterized via dissolution testing, Fourier Transform infra-red spectroscopy, differential scanning calorimetry, and scanning electron microscopy. Results: The used methods showed a significant enhancement in dug dissolution rate; physical mixing significantly, p < 0.05, increased the percentage of the drug released with time; for example, bendroflumethiazide dissolution in distilled water was improved from less than 20% to 99.79% within 90 min for physically mixed drug-cyclodextrin 1:5. The lyophilisation process was enhanced and the drug dissolution rate and the highest drug dissolution was achieved for (drug-gluconolactone 1:1) with 98.98% drug release within 90 min. Conclusions: the physical mixing and freeze drying processes significantly increased the percentage of drug release with time. Full article
(This article belongs to the Special Issue Dissolution Enhancement of Poorly Soluble Drugs)
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