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1.
Environ Sci Pollut Res Int ; 30(53): 114610-114624, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37863854

ABSTRACT

Microalgae have the potential as a source of biofuels due to their high biomass productivity and ability to grow in a wide range of conditions, including wastewater. This study investigated cultivating two microalgae species, Oocystis pusilla and Chlorococcus infusionum, in wastewater for biodiesel production. Compared to Kühl medium, KC medium resulted in a significant fold increase in cellular dry weight production for both O. pusilla and C. infusionum, with an increase of 1.66 and 1.39, respectively. A concentration of 100% wastewater resulted in the highest growth for O. pusilla, with an increase in biomass and lipid content compared to the KC medium. C. infusionum could not survive in these conditions. For further increase in biomass and lipid yield of O. pusilla, different total dissolved solids (TDS) levels were used. Maximum biomass and lipid productivities were achieved at 3000 ppm TDS, resulting in a 28% increase in biomass (2.50 g/L) and a 158% increase in lipid yield (536.88 mg/g) compared to KC medium. The fatty acid profile of O. pusilla cultivated on aerated wastewater at 3000 ppm TDS showed a high proportion of desirable saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) for biodiesel production. Cultivating microalgae in wastewater for biodiesel production can be cost-effective, especially for microalgae adapted to harsh conditions. It could be concluded that O. pusilla is a promising candidate for biodiesel production using wastewater as a growth medium, as it has high biomass productivity and lipid yield, and its fatty acid profile meets the standard values of American and European biodiesel standards. This approach offers a sustainable and environmentally friendly solution for producing biofuels while reducing the environmental impact of wastewater disposal.


Subject(s)
Microalgae , Wastewater , Biofuels , Fatty Acids , Salt Stress , Biomass
2.
Mol Pharm ; 20(2): 929-941, 2023 02 06.
Article in English | MEDLINE | ID: mdl-36592951

ABSTRACT

Sodium caprate (C10) has been widely evaluated as an intestinal permeation enhancer for the oral delivery of macromolecules. However, the effect of C10 on the intestinal absorption of peptides with different physicochemical properties and its permeation-enhancing effect in vivo remains to be understood. Here, we evaluated the effects of C10 on intestinal absorption in rats with a glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GIP-GLP1) dual agonist peptide (LY) and semaglutide with different enzymatic stabilities and self-association behaviors as well as the oral exposure of the LY peptide in minipigs. Furthermore, we investigated the mechanism of action (MoA) of C10 for improving the intestinal absorption of the LY peptide in vivo via live imaging of the rat intestinal epithelium and tissue distribution of the LY peptide in minipigs. The LY peptide showed higher proteolytic stability in pancreatin and was a monomer in solution compared to that in semaglutide. C10 increased in vitro permeability in the minipig intestinal organoid monolayer to a greater extent for the LY peptide than for semaglutide. In the rat jejunal closed-loop model, C10 increased the absorption of LY peptide better than that of semaglutide, which might be attributed to higher in vitro proteolytic stability and permeability of the LY peptide. Using confocal live imaging, we observed that C10 enabled the rapid oral absorption of a model macromolecule (FD4) in the rat intestine. In the duodenum tissues of minipigs, C10 was found to qualitatively reduce the tight junction protein level and allow peptide uptake to the intestinal cells. C10 decreased the transition temperature of the artificial lipid membrane, indicating an increase in membrane fluidity, which is consistent with the above in vivo imaging results. These data indicated that the LY's favorable physicochemical properties combined with the effects of C10 on the intestinal mucosa resulted in an ∼2% relative bioavailability in minipigs.


Subject(s)
Gastric Inhibitory Polypeptide , Glucagon-Like Peptide 1 , Swine , Rats , Animals , Gastric Inhibitory Polypeptide/metabolism , Gastric Inhibitory Polypeptide/pharmacology , Glucagon-Like Peptide 1/metabolism , Swine, Miniature/metabolism , Decanoic Acids/pharmacology , Intestinal Absorption , Intestinal Mucosa/metabolism , Peptides/metabolism
3.
BMC Nurs ; 21(1): 365, 2022 Dec 21.
Article in English | MEDLINE | ID: mdl-36544166

ABSTRACT

BACKGROUND: Hypertension diagnosis, treatment, and follow-up depend on accurate blood pressure measurement; however, inaccurate measurement techniques are common among healthcare providers. To improve professional performance, continuous education is necessary. Distance education through virtual social network can be used as it is easy to use and accessible. METHODS: This study adopted a randomized controlled trial design and was conducted at two hospitals in Mansoura, Egypt. The subjects were selected from two hospitals using Stratified random sampling method in proportion to the total number of nurses. Seventy nurses were included in this study and were randomly divided into the intervention (n = 35) and control (n = 35) groups using block randomization. Data were gathered before and after intervention using a blood pressure measurement knowledge questionnaire and a blood pressure measurement observation checklist. The blood pressure measurement error (the difference between the BP determined by each observer and the reference BP) was calculated for the randomly selected recordings in both groups. The intervention group received 24 blood pressure measurement education sessions using WhatsApp, while the control group received only routine education using traditional lecture. RESULTS: No statistically significant differences in pretest knowledge scores, performance scores, and range of error were found between both groups, whereas, after intervention, knowledge scores were higher in the intervention group than those in the control group (p < 0.001). The range of error of systolic and diastolic blood pressure values significantly reduced after the intervention in the intervention group, and the posttest performance scores were higher than the pretest performance scores; however, the difference was not statistically significant. CONCLUSIONS: The blood pressure measurement education program via WhatsApp was effective in increasing nurses' knowledge and reducing the range of error; however, a multimodal approach may be required to improve performance scores. TRIAL REGISTRATION: Prospectively registered with ClinicalTrials.gov on 09/03/2021; registration number NCT04789642.

4.
BMC Nurs ; 21(1): 316, 2022 Nov 16.
Article in English | MEDLINE | ID: mdl-36384544

ABSTRACT

BACKGROUND: Flipped learning excessively boosts the conceptual understanding of students through the reversed arrangement of pre-learning and in classroom learning events and challenges students to independently achieve learning objectives. Using a gamification method in flipped classrooms can help students stay motivated and achieve their goals.  METHODS: This study adopted a randomized controlled study design with a pre-test and post-test and involved 128 nursing students at Mansoura University. This study randomly divided the students into the study and control groups. Data were collected at three time points using six tools. In the intervention group, Moodle was gamified for 6 weeks.  RESULTS: A significant difference in the students' self-confidence (p = 0.021), skills knowledge (p < 0.001), intensity of preparation (p < 0.001), and motivation (p < 0.001) was observed between the two groups; however, no difference in the students' skills performance (p = 0.163) was observed between the two groups after using gamified flipped classrooms. CONCLUSIONS: Compared with the traditional flipped classrooms, gamified flipped classrooms improved nursing students' motivation, intensity of preparation, skills knowledge, and self-confidence during laboratory clinical practice. Thus, gamification is a learning approach that can be implemented in conjunction with the flipped classroom model to motivate students to participate in the learning process. TRIAL REGISTRATION: Prospectively registered with ClinicalTrials.gov on 26/04/2021; registration number NCT04859192.

5.
Pharm Res ; 39(10): 2555-2567, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36050547

ABSTRACT

PURPOSE: Oral delivery of therapeutic peptides has been challenging due to multiple physiological factors and physicochemical properties of peptides. We report a systematic approach to identify formulation compositions combining a permeation enhancer and a peptidase inhibitor that minimize proteolytic degradation and increase absorption of a peptide across the small intestine. METHODS: An acylated glucagon-like peptide-1/glucagon co-agonist peptide (4.5 kDa) was selected as a model peptide. Proteolytic stability of the peptide was investigated in rat and pig SIF. Effective PEs and multiple component formulations were identified in rats. Relative bioavailability of the peptide was determined in minipigs via intraduodenal administration (ID) of enteric capsules. RESULTS: The peptide degraded rapidly in the rat and pig SIF. Citric acid, SBTI, and SBTCI inhibited the enzymatic degradation. The peptide self-associated into trimers in solution, however, addition of PEs monomerized the peptide. C10 was the most effective PE among tested PEs (DPC, LC, rhamnolipid, C12-maltosides, and SNAC) to improve intestinal absorption of the peptide in the rat IJ-closed loop model. A combination of C10 and SBTI or SBTCI increased the peptide exposure 5-tenfold compared to the exposure with the PE alone in the rat IJ-cannulated model, and achieved 1.06 ± 0.76% bioavailability in minipigs relative to subcutaneous via ID administration using enteric capsules. CONCLUSION: We identified SBTI and C10 as an effective peptidase inhibitor and PE for intestinal absorption of the peptide. The combination of SBTI and C10 addressed the peptide physiochemical properties and provides a formulation strategy to achieve intestinal delivery of this peptide.


Subject(s)
Glucagon-Like Peptide 1 , Glucagon , Animals , Capsules , Citric Acid , Intestinal Absorption , Peptide Hydrolases , Peptides/pharmacology , Protease Inhibitors , Rats , Swine , Swine, Miniature/metabolism
6.
Eur Rev Med Pharmacol Sci ; 26(10): 3456-3468, 2022 05.
Article in English | MEDLINE | ID: mdl-35647826

ABSTRACT

OBJECTIVE: To determine whether neuromuscular electrical stimulation of calf muscles could improve nocturnal symptoms and quality of life in asthmatic children. PATIENTS AND METHODS: Sixty children (8-12 years) with moderate asthma were randomly allocated to three groups (A, B, and C). The three groups completed 12 weeks of supervised breathing exercises for 30 min. In addition, group A completed neuromuscular electrical stimulation of the calf muscles and group B completed aerobic exercise in the same period. The intervention was conducted five days a week for 12 consecutive weeks. Pre-and post-treatment evaluations involved pulmonary function tests, the Children's Asthma Control Questionnaire, calf muscle isometric muscle force, six-minute walk test, and Pediatric Asthma Quality of Life Questionnaire. RESULTS: A significant increase in all measured variables was recorded in all groups in favor of group A (p < 0.001). However, calf muscle isometric muscle strength, and nocturnal symptoms were non-significant in group C (p > 0.05). There was a significant difference between groups A and C in all measured variables (p < 0.001) in favor of group A. Significant differences between groups B and C in all measured variables (p < 0.001) in favor of group B were also noted. No significant differences were seen between groups A and B (p > 0.05). CONCLUSIONS: Neuromuscular electrical stimulation of calf muscles is an excellent adjunct to breathing exercise programs in improving nocturnal symptoms and quality of life in asthmatic children. Moreover, it can serve as a considerable alternative to traditional physical training in periods of disease exacerbation.


Subject(s)
Asthma , Quality of Life , Asthma/therapy , Child , Electric Stimulation , Humans , Leg , Muscle, Skeletal/physiology
7.
Adv Drug Deliv Rev ; 186: 114322, 2022 07.
Article in English | MEDLINE | ID: mdl-35526665

ABSTRACT

Peptides, an emerging modality within the biopharmaceutical industry, are often delivered subcutaneously with evolving prospects on oral delivery. Barrier biology within the subcutis or gastrointestinal tract is a significant challenge in limiting absorption or otherwise disrupting peptide disposition. Aspects of peptide pharmacokinetic performance and ADME can be mitigated with careful molecular design that tailors for properties such as effective size, hydrophobicity, net charge, proteolytic stability, and albumin binding. In this review, we endeavor to highlight effective techniques in qualifying physicochemical properties of peptides and discuss advancements of in vitro models of subcutaneous and oral delivery. Additionally, we will delineate empirical findings around the relationship of these physicochemical properties and in vivo (animal or human) impact. We conclude that robust peptide characterization methods and in vitro techniques with demonstrated correlations to in vivo data are key routines to incorporate in the drug discovery and development to improve the probability of technical and commercial success of peptide therapeutics.


Subject(s)
Biological Products , Peptides , Administration, Oral , Animals , Biological Products/metabolism , Drug Discovery , Gastrointestinal Tract/metabolism , Humans , Hydrophobic and Hydrophilic Interactions
8.
Expert Opin Drug Deliv ; 19(2): 163-178, 2022 02.
Article in English | MEDLINE | ID: mdl-35255753

ABSTRACT

INTRODUCTION: Numerous formulation technologies have been developed to overcome challenges of oral peptide delivery. Understanding the advantages and limitations of each technology is important for the development of new delivery systems to enable oral delivery of peptides designed for parenteral administration. AREAS COVERED: This review summarizes key learnings from the use of permeation enhancers (PEs) for oral peptide delivery associated with solid dosage form optimization to maximize the PE effect. Furthermore, we will highlight the most recent emerging delivery strategies to improve oral peptide bioavailability such as nanoparticles, self-emulsifying drug delivery systems, gut shuttles, and ingestible devices. In addition, advantages and limitations of these technologies will be compared with the permeation enhancer technology. EXPERT OPINION: Despite the success of permeation enhancer technology in the FDA-approved oral peptide products, oral peptide delivery is still facing the immense challenge of low-to-single digit oral bioavailability. Optimization of drug product attributes such as dissolution kinetics is critical to improve permeation enhancer efficacy. The next frontiers to substantially increase oral bioavailability and transform injectable peptides to oral deliverables may be ingestible devices and ligand-mediated transport (gut shuttles). However, clinical studies are necessary to inform the safety and efficacy of these emerging technologies.


Subject(s)
Drug Delivery Systems , Peptides , Administration, Oral , Biological Availability , Pharmaceutical Preparations
9.
Stud Health Technol Inform ; 289: 216-219, 2022 Jan 14.
Article in English | MEDLINE | ID: mdl-35062131

ABSTRACT

Left bundle branch block (LBBB) is a frequent source of false positive MPI reports, in patients evaluated for coronary artery disease. PURPOSE: In this work, we evaluated the ability of a CNN-based solution, using transfer learning, to produce an expert-like judgment in recognizing LBBB false defects. METHODS: We collected retrospectively, MPI polar maps, of patients having small to large fixed anteroseptal perfusion defect. Images were divided into two groups. The LBBB group included patients where this defect was judged as false defect by two experts. The LAD group included patients where this defect was judged as a true defect by two experts. We used a transfer learning approach on a CNN (ResNet50V2) to classify the images into two groups. RESULTS: After 60 iterations, the reached accuracy plateau was 0.98, and the loss was 0.19 (the validation accuracy and loss were 0.91 and 0.25, respectively). A first test set of 23 images was used (11 LBBB, and 12 LAD). The empiric ROC (Receiver operating characteristic) Area was estimated at 0.98. A second test set (18x2 images) was collected after the final results. The ROC area was estimated again at 0.98. CONCLUSION: Artificial intelligence, using CNN and transfer learning, could reproduce an expert-like judgment in differentiating between LBBB false defects, and LAD real defects.


Subject(s)
Bundle-Branch Block , Myocardial Perfusion Imaging , Artificial Intelligence , Bundle-Branch Block/diagnostic imaging , Humans , Neural Networks, Computer , Retrospective Studies , Tomography, Emission-Computed, Single-Photon
10.
Sci Total Environ ; 792: 148359, 2021 Oct 20.
Article in English | MEDLINE | ID: mdl-34147795

ABSTRACT

The high demand for sufficient and safe food, and continuous damage of environment by conventional agriculture are major challenges facing the globe. The necessity of smart alternatives and more sustainable practices in food production is crucial to confront the steady increase in human population and careless depletion of global resources. Nanotechnology implementation in agriculture offers smart delivery systems of nutrients, pesticides, and genetic materials for enhanced soil fertility and protection, along with improved traits for better stress tolerance. Additionally, nano-based sensors are the ideal approach towards precision farming for monitoring all factors that impact on agricultural productivity. Furthermore, nanotechnology can play a significant role in post-harvest food processing and packaging to reduce food contamination and wastage. In this review, nanotechnology applications in the agriculture and food sector are reviewed. Implementations of nanotechnology in agriculture have included nano- remediation of wastewater for land irrigation, nanofertilizers, nanopesticides, and nanosensors, while the beneficial effects of nanomaterials (NMs) in promoting genetic traits, germination, and stress tolerance of plants are discussed. Furthermore, the article highlights the efficiency of nanoparticles (NPs) and nanozymes in food processing and packaging. To this end, the potential risks and impacts of NMs on soil, plants, and human tissues and organs are emphasized in order to unravel the complex bio-nano interactions. Finally, the strengths, weaknesses, opportunities, and threats of nanotechnology are evaluated and discussed to provide a broad and clear view of the nanotechnology potentials, as well as future directions for nano-based agri-food applications towards sustainability.


Subject(s)
Nanostructures , Pesticides , Agriculture , Food Industry , Humans , Nanotechnology
11.
Expert Opin Drug Discov ; 16(12): 1467-1482, 2021 12.
Article in English | MEDLINE | ID: mdl-34187273

ABSTRACT

Introduction: To discover and develop a peptide, protein, or antibody into a drug requires overcoming multiple challenges to obtain desired properties. Proteolytic stability is one of the challenges and deserves a focused investigation.Areas covered: This review concentrates on improving proteolytic stability by engineering the amino acids around the cleavage sites of a liable peptide, protein, or antibody. Peptidases are discussed on three levels including all peptidases in databases, mixtures based on organ and tissue types, and individual peptidases. The technique to identify cleavage sites is spotlighted on mass spectrometry-based approaches such as MALDI-TOF and LC-MS. For sequence engineering, the replacements that have been commonly applied with a higher chance of success are highlighted at the beginning, while the rarely used and more complicated replacements are discussed later. Although a one-size-fits-all approach does not exist to apply to different projects, this review provides a 3-step strategy for effectively and efficiently conducting the proteolytic stability experiments to achieve the eventual goal of improving the stability by engineering the molecule itself.Expert opinion: Improving the proteolytic stability is a spiraling up process sequenced by testing and engineering. There are many ways to engineer amino acids, but the choice must consider the cost and properties affected by the changes of the amino acids.


Subject(s)
Peptides , Proteins , Drug Discovery , Humans , Peptide Hydrolases , Peptides/chemistry , Proteins/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods
12.
Environ Sci Pollut Res Int ; 27(26): 32481-32493, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32506400

ABSTRACT

The present study evaluated the sequential biodiesel-bioethanol production from seaweeds. A total of 22 macroalgal species were collected at different seasons and screened based on lipid and carbohydrate contents as well as biomass production. The promising species was selected, based on the relative increase in energy compounds (REEC, %), for further energy conversion. Seasonal and annual biomass yields of the studied species showed significant variations. The rhodophyte Amphiroa compressa and the chlorophyte Ulva intestinalis showed the highest annual biomass yield of 75.2 and 61.5 g m-2 year-1, respectively. However, the highest annual carbohydrate productivity (ACP) and annual lipid productivity (ALP) were recorded for Ulva fasciata and Ulva intestinalis (17.0 and 3.0 g m-2 year-1, respectively). The later was selected for further studies because it showed 14.8% higher REEC value than Ulva fasciata. Saturated fatty acids (SAFs) showed 73.4%, with palmitic acid as a dominant fatty acid (43.8%). Therefore, biodiesel showed high saturation degree, with average degree of unsaturation (ADU) of 0.508. All the measured biodiesel characteristics complied the international standards. The first route of biodiesel production (R1) from Ulva intestinalis showed biodiesel recovery of 32.3 mg g-1 dw. The hydrolysate obtained after saccharification of the whole biomass (R2) and lipid-free biomass (R3) contained 1.22 and 1.15 g L-1, respectively, reducing sugars. However, bioethanol yield from R3 was 0.081 g g-1 dw, which represented 14.1% higher than that of R2. Therefore, application of sequential biofuel production using R3 resulted in gross energy output of 3.44 GJ ton-1 dw, which was 170.9% and 82.0% higher than R1 and R2, respectively. The present study recommended the naturally-grown Ulva intestinalis as a potential feedstock for enhanced energy recovery through sequential biodiesel-bioethanol production.


Subject(s)
Seaweed , Ulva , Biofuels , Biomass , Fatty Acids
13.
Saudi Med J ; 41(5): 516-523, 2020 May.
Article in English | MEDLINE | ID: mdl-32373919

ABSTRACT

OBJECTIVES: To identify the knowledge gap and misconceptions about osteoarthritis (OA) and its risk factors among the general population of Jeddah, Saudi Arabia. METHODS: This is a cross-sectional study conducted Jeddah, Saudi Arabia, between 11-13 April, 2019. The study was approved by King Abdullah International Medical Research Center. A representative sample of the public in well-known mall was asked to complete the questionnaire to assess their knowledge regarding OA. The questionnaire consisted of 3 parts: 1) demographic data, 2) general knowledge regarding OA, and 3) a quiz of 20 questions. A descriptive analysis was carried out with t-test and F-test-based method. RESULTS: The study had 1238 respondents. Approximately 55% of them were females, with 51.8% between the ages of 18 to 29. Approximately 62% held a bachelor's degree and 63% had a family member or a friend afflicted with OA. Relatives and friends were the main source of information regarding OA. Only 37% correctly identified the mechanism behind OA. The mean score for the 20-item quiz was 9.84. No significant differences were found when comparing scores of males and females or those of age groups. However, significant differences in scores were identified between respondents of varying educational levels (p less than 0.001), participants' knowledge of the mechanism leading to OA (p less than 0.001), information sources (p less than 0.001), and knowing someone with it (p less than 0.001). CONCLUSION: The results of our study suggest a low level of knowledge regarding OA among Jeddah population. Many misconceptions regarding OA were identified, so more information be brought to the public.


Subject(s)
Health Knowledge, Attitudes, Practice , Osteoarthritis , Adolescent , Adult , Cross-Sectional Studies , Educational Status , Family , Female , Humans , Male , Risk Factors , Saudi Arabia , Surveys and Questionnaires , Time Factors , Young Adult
14.
Trop Anim Health Prod ; 52(5): 2327-2332, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32157519

ABSTRACT

The serostatus of enzootic bovine leukosis (EBL) was determined at three dairy farms and the Al Ain Livestock Market (AALM), within the Al Ain region of Abu Dhabi, UAE. Of the 957 bovine sera tested by ELISA, 657 were from Holstein-Friesians from three dairy farms, and 300 from Bos indicus cattle at AALM. The chi-square homogeneity test (CSHT) and the Marascuilo multiple comparison procedure (MMCP) assessed the level of significance between the proportions of EBL-seropositive cattle (ESPC) across the study farms and AALM, and between the age groups at farms 1 and 3. Overall, the proportion of ESPC was 25.7% at dairy farms and AALM, 37.0% for farms and 1.0% for AALM. Furthermore, the proportions of ESPC at farms 1, 2 and 3 were 54.7%, 0.0% and 26.3% respectively, and statistically significant differences were seen across the farm/farm and farm/AALM comparisons, and between two age groups at farms 1 and 3. The 37-72-month-old age group showed the highest proportion of ESPC. This is the first serological evidence of EBL in the UAE. As previously reported, the ESPC are comparatively higher in dairy than Bos indicus cattle. Molecular and more extensive serological studies are needed to further corroborate the present data. Meanwhile, the UAE veterinary authorities will need to formulate national EBL control policies.


Subject(s)
Enzootic Bovine Leukosis/epidemiology , Animals , Antibodies, Viral/blood , Cattle , Enzootic Bovine Leukosis/blood , Enzootic Bovine Leukosis/immunology , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Leukemia Virus, Bovine/immunology , United Arab Emirates/epidemiology
15.
Pharm Res ; 36(6): 89, 2019 Apr 19.
Article in English | MEDLINE | ID: mdl-31004235

ABSTRACT

PURPOSE: To develop a planar, asymmetric, micro-scale oral drug delivery vehicle by i) fabricating microdevice bodies with enteric materials, ii) efficiently and stably loading sensitive drug molecules, and iii) capping microdevices for controlled drug release. METHODS: Picoliter-volume inkjet printing was used to fabricate microdevices through additive manufacturing via drop-by-drop deposition of enteric polymer materials. Microdevice bodies with reservoirs are fabricated through deposition of an enteric polymer, Eudragit FS 30 D. A model API, insulin, was loaded into each microdevice and retained its stability during printing and release. Eudragit L 100 and/or S 100 were used to cap microdevices and control the kinetics of insulin release in simulated intestinal conditions. RESULTS: Microdevice morphologies and size can be tuned on the fly based on printing parameters to span from the microscale to the mesoscale. Insulin retained its stability throughout device fabrication and during in vitro release in simulated intestinal conditions. Insulin release kinetics, from burst release to no release, can be tailored by controlling the blend of the Eudragit capping material. CONCLUSION: This approach represents a uniquely scalable and flexible strategy for microdevice fabrication that overcomes limitations in loading sensitive biologics and in the tuneability of device geometries that are inherent to traditional microfabrication strategies.


Subject(s)
Delayed-Action Preparations/chemistry , Drug Delivery Systems/instrumentation , Equipment Design/instrumentation , Insulins/chemistry , Polyvinyls/chemistry , Administration, Oral , Delayed-Action Preparations/administration & dosage , Drug Liberation , Excipients/chemistry , Insulins/administration & dosage , Microspheres , Particle Size , Printing, Three-Dimensional , Surface Properties
16.
J Control Release ; 289: 79-93, 2018 11 10.
Article in English | MEDLINE | ID: mdl-30149048

ABSTRACT

Overexpression of RhoC protein in breast cancer patients has been linked to increased cancer cell invasion, migration, and metastases. Suppressing RhoC expression in aggressive breast cancer cells using silencing RNA (siRNA) molecules is a viable strategy to inhibit the metastatic spread of breast cancer. In this report, we describe the synthesis of a series of asymmetric pH-sensitive, membrane-destabilizing polymers engineered to complex anti-RhoC siRNA molecules forming "smart" nanoparticles. Using ß-CD as the particle core, polyethylene glycol (PEG) chains were conjugated to the primary face via non-cleavable bonds and amphiphilic polymers incorporating hydrophobic and cationic monomers were grafted to the secondary face via acid-labile linkages. We investigated the effect of PEG molecular weight (2 & 5 kDa) on transfection capacity and serum stability of the formed particles. We evaluated the efficacy of EPPT1 peptides presented on the free tips of the PEG brush to function as a targeting ligand against underglycosylated MUC1 (uMUC1) receptors overexpressed on the surface of metastatic breast cancer cells. Results show that "smart" nanoparticles successfully delivered anti-RhoC siRNA into the cytoplasm of aggressive SUM149 and MDA-MB-231 breast cancer cells, which resulted in a dose-dependent inhibition of cell migration and invasion. Further, EPPT1-targeted nanoparticles demonstrate a synergistic inhibition of cell migration and invasion imparted via RhoC knockdown and EPPT1-mediated signaling via the uMUC1 receptor.


Subject(s)
Breast Neoplasms/therapy , Nanocapsules/chemistry , Neoplasm Invasiveness/prevention & control , Oligopeptides/metabolism , RNA Interference , RNA, Small Interfering/administration & dosage , rhoC GTP-Binding Protein/genetics , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Membrane Permeability , Cell Movement , Cell Proliferation , Drug Liberation , Female , Gene Expression Regulation, Neoplastic , Gene Knockdown Techniques/methods , Humans , Mucin-1/metabolism , Oligopeptides/chemistry , Polyethylene Glycols/chemistry , Polymerization , Transfection , Tumor Microenvironment , beta-Cyclodextrins/chemistry , rhoC GTP-Binding Protein/metabolism
17.
Int J Pharm ; 545(1-2): 27-36, 2018 Jul 10.
Article in English | MEDLINE | ID: mdl-29673805

ABSTRACT

The display of N-acetylgalactosamine (NAcGal) ligands has shown great potential in improving the targeting of various therapeutic molecules to hepatocellular carcinoma (HCC), a severe disease whose clinical treatment is severely hindered by limitations in delivery of therapeutic cargo. We previously used the display of NAcGal on generation 5 (G5) polyamidoamine (PAMAM) dendrimers connected through a poly(ethylene glycol) (PEG) brush (i.e. G5-cPEG-NAcGal; monoGal) to effectively target hepatic cancer cells and deliver a loaded therapeutic cargo. In this study, we were interested to see if tri-valent NAcGal ligands (i.e. NAcGal3) displayed on G5 dendrimers (i.e. G5-cPEG-NAcGal3; triGal) could improve their ability to target hepatic cancer cells compared to their monoGal counterparts. We therefore synthesized a library of triGal particles, with either 2, 4, 6, 8, 11, or 14 targeting branches (i.e. cPEG-NAcGal3) attached. Conventional flow cytometry studies showed that all particle formulations can label hepatic cancer cells in a concentration-dependent manner, reaching 90-100% of cells labeled at either 285 or 570 nM G5, but interestingly, monoGal labeled more cells at lower concentrations. To elucidate the difference in internalization of monoGal versus triGal conjugates, we turned to multi-spectral imaging flow cytometry and quantified the amount of internalized (I) versus surface-bound (I0) conjugates to determine the ratio of internalization (I/I0) in all treatment groups. Results show that regardless of NAcGal valency, or the density of targeting branches, all particles achieve full internalization and diffuse localization throughout the cell (I/I0 ∼ 3.0 for all particle compositions). This indicates that while tri-valent NAcGal is a promising technique for targeting nanoparticles to hepatic cancer cells, mono-valent NAcGal is more efficient, contrary to what is observed with small molecules.


Subject(s)
Acetylgalactosamine/metabolism , Carcinoma, Hepatocellular/metabolism , Dendrimers/metabolism , Drug Carriers , Liver Neoplasms/metabolism , Polyamines/metabolism , Acetylgalactosamine/analogs & derivatives , Acetylgalactosamine/chemical synthesis , Biological Transport , Carcinoma, Hepatocellular/pathology , Dendrimers/chemical synthesis , Drug Compounding , Flow Cytometry , Hep G2 Cells , Humans , Ligands , Liver Neoplasms/pathology , Polyamines/chemical synthesis , Polyethylene Glycols/chemistry , Technology, Pharmaceutical/methods
18.
R Soc Open Sci ; 5(2): 171220, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29515841

ABSTRACT

The stability of an emulsified liquid membrane composed of Span80 as a surfactant, D2EHPA as an extractant and sulfuric acid as an internal phase was first studied according to different diluents and many operating parameters using the Plackett-Burman design of experiments. Then the removal of methylene blue from an aqueous solution has been carried out using this emulsified liquid membrane at its stability conditions. The effects of operating parameters were analysed from the Box-Behnken design of experiments. The optimization of the extraction has been realized applying the response surface methodology and the results showed that the dye extraction yielding 98.72% was achieved at optimized conditions.

19.
PLoS One ; 12(8): e0181944, 2017.
Article in English | MEDLINE | ID: mdl-28829785

ABSTRACT

Hepatocellular carcinoma (HCC) is the 2nd leading cause of cancer-related deaths every year globally. The most common form of treatment, hepatic arterial infusion (HAI), involves the direct injection of doxorubicin (DOX) into the hepatic artery. It is plagued with limited therapeutic efficacy and the occurrence of severe toxicities (e.g. cardiotoxicity). We aim to improve the therapeutic index of DOX delivered via HAI by loading the drug onto generation 5 (G5) poly(amidoamine) (PAMAM) dendrimers targeted to hepatic cancer cells via N-acetylgalactosamine (NAcGal) ligands. DOX is attached to the surface of G5 molecules via two different enzyme-sensitive linkages, L3 or L4, to achieve controllable drug release inside hepatic cancer cells. We previously reported on P1 and P2 particles that resulted from the combination of NAcGal-targeting with L3- or L4-DOX linkages, respectively, and showed controllable DOX release and toxicity towards hepatic cancer cells comparable to free DOX. In this study, we demonstrate that while the intratumoral delivery of free DOX (1 mg/kg) into HCC-bearing nod scid gamma (NSG) mice achieves a 2.5-fold inhibition of tumor growth compared to the saline group over 30 days, P1 and P2 particles delivered at the same DOX dosage achieve a 5.1- and 4.4-fold inhibition, respectively. Incubation of the particles with human induced pluripotent stem cell derived cardiomyocytes (hiPSC CMs) showed no effect on monolayer viability, apoptosis induction, or CM electrophysiology, contrary to the effect of free DOX. Moreover, magnetic resonance imaging revealed that P1- and P2-treated mice maintained cardiac function after intraperitoneal administration of DOX at 1 mg/kg for 21 days, unlike the free DOX group at an equivalent dosage, confirming that P1/P2 can avoid DOX-induced cardiotoxicity. Taken together, these results highlight the ability of P1/P2 particles to improve the therapeutic index of DOX and offer a replacement therapy for clinical HCC treatment.


Subject(s)
Antibiotics, Antineoplastic/chemistry , Carcinoma, Hepatocellular/drug therapy , Dendrimers/chemistry , Doxorubicin/chemistry , Heart/drug effects , Liver Neoplasms, Experimental/drug therapy , Animals , Antibiotics, Antineoplastic/pharmacology , Doxorubicin/pharmacology , Female , Hep G2 Cells , Humans , Male , Mice
20.
Pharm Res ; 34(10): 2197-2210, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28721446

ABSTRACT

PURPOSE: This report describes the effect of rhamnolipids (RLs) on the tight junctions (TJ) of the intestinal epithelium using the rat in-situ closed loop model. METHODS: We investigated the transport of 5 (6)-carboxyfluorescein (CF) and fluorescein isothiocyanate-labeled dextrans with average molecular weights of 4.4 and 10 kDa (FD-4 and FD-10) when co-administered with different concentrations of RLs. Lactate dehydrogenase (LDH) leakage assay and histopathological examination of treated intestinal loops were used to assess potential toxicity of RLs. Further, the effect of kaempferol on accelerating the resealing of the tight junctions in vivo was also investigated RESULTS: Data shows that administration of different RLs concentrations (1.0-5.0% v/v) increased CF absorption through rat intestine by 2.84- and 15.82-folds with RLs concentrations of 1.0% and 5.0% v/v, respectively. RLs exhibited size-dependent increase on FD-4 and FD-10 absorption. Dosing RLs at 1.0% v/v didn't cause a significant LDH leakage or histopathological changes to intestinal mucosa compared to higher concentrations, which showed a progressive damaging effect. Using kaempferol, a natural flavonoid that stimulates the assembly of the TJs, proved to enhance the recovery of barrier properties of the intestinal mucosa treated with high concentrations of RLs (2.5% and 5% v/v). CONCLUSIONS: These results collectively illustrate the ability of RLs to enhance oral bioavailability of different molecules across the intestinal epithelial membrane in a concentration- and time-dependent fashion.


Subject(s)
Glycolipids/metabolism , Kaempferols/metabolism , Administration, Oral , Animals , Biological Availability , Fluorescent Dyes/chemistry , Glycolipids/administration & dosage , Glycolipids/chemistry , Humans , Intestinal Absorption , Intestinal Mucosa/metabolism , Kaempferols/administration & dosage , Kaempferols/chemistry , Male , Molecular Weight , Permeability , Rats , Rats, Wistar
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