Publications by authors named "Khaled Shalaby"

16 Publications

  • Page 1 of 1

Olive Oil/Pluronic Oleogels for Skin Delivery of Quercetin: In Vitro Characterization and Ex Vivo Skin Permeability.

Polymers (Basel) 2021 May 31;13(11). Epub 2021 May 31.

Department of Pharmaceutics, Faculty of Pharmacy, Ahram Canadian University, Giza 14756, Egypt.

The main objective of this study was to prepare and characterize oleogel as potential carrier for quercetin skin delivery. The formulations were prepared by adding olive oil (5-30%) to Pluronic F127 hydrogel and were evaluated for particle size, zeta potential, viscosity in vitro quercetin release and stability, and were compared with that of Pluronic F127 hydrogel. The selected formulation was characterized for its interaction possibility, ex vivo skin permeation and skin histological changes and safety. The particle sizes ranged from 345.3 ± 5.3 nm to 401.5 ± 2.8 nm, and possessed negative charges. The viscosities of the formulations were found in the range of 6367-4823 cps with inverse proportionality to olive oil percentage while the higher percentages showed higher quercetin release. Percentages of 25% and 30% olive oil showed instability pattern under the conditions of accelerated stability studies. Differential scanning calorimetry verified the existence of quercetin in micellar aggregation and the network in the case of hydrogel and oleogel respectively. Ex vivo skin permeation showed an improved skin permeation of quercetin when 20% olive oil containing oleogel was used. Skin histology after 10 days of application showed stratum corneum disruption and good safety profile. Based on these findings, the proposed oleogel containing 20% olive oil denotes a potential carrier for topical delivery of quercetin.
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http://dx.doi.org/10.3390/polym13111808DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8198417PMC
May 2021

Mucoadhesive In Situ Rectal Gel Loaded with Rifampicin: Strategy to Improve Bioavailability and Alleviate Liver Toxicity.

Pharmaceutics 2021 Mar 5;13(3). Epub 2021 Mar 5.

Department of Chemistry, College of Science, Jouf University, Sakaka P.O. Box 2014, Saudi Arabia.

Although it is a front-line in tuberculosis treatment, rifampicin (RF) exhibits poor oral bioavailability and hepatotoxicity. Rectal mucoadhesive and in situ rectal gels were developed to overcome drug drawbacks. A RF/polyethylene glycol 6000 co-precipitate was first prepared in different ratios. Based on the drug solubility, the selected ratio was investigated for drug/polymer interaction and then incorporated into in situ rectal gels using Pluronic F127 (15%) and Pluronic F68 (10%) as a gel base and mucoadhesive polymers (HPMC, sodium alginate and chitosan). The formulations were assessed for gelation temperature and gel strength. The selected formulation was investigated for in vivo assessments. The results showed that a 1:1 drug/polymer ratio exhibited satisfying solubility with the recorded drug/polymer interaction. Depending on their concentrations, adding mucoadhesive polymers shifted the gelation temperature to lower temperatures and improved the gel strength. The selected formulation (F4) did not exhibit any anal leakage or marked rectal irritation. Using a validated chromatographic analytical method, F4 exhibited higher drug absorption with a 3.38-fold and 1.74-fold higher bioavailability when compared to oral drug suspension and solid suppositories, respectively. Toxicity studies showed unnoticeable hepatic injury in terms of biochemical, histopathological and immunohistochemical examinations. Together, F4 showed a potential of enhanced performance and also offered lower hepatic toxicity, thus offering an encouraging therapeutic alternative.
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http://dx.doi.org/10.3390/pharmaceutics13030336DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8001001PMC
March 2021

Development and machine-learning optimization of mucoadhesive nanostructured lipid carriers loaded with fluconazole for treatment of oral candidiasis.

Drug Dev Ind Pharm 2021 Feb 8;47(2):246-258. Epub 2021 Jan 8.

Faculty of Pharmacy, Department of Pharmaceutics and Industrial Pharmacy, Beni-Suef University, Beni-Suef, Egypt.

The aim of this work was to prepare and optimize mucoadhesive nanostructured lipid carrier (NLC) impregnated with fluconazole for better management of oral candidiasis. The NLCs were fabricated using an emulsification/sonication technique. The nanoparticles consisted of stearic acid, oleic acid, Pluronic F127, and lecithin. Box-Behnken design, artificial neural networking, and variable weight desirability were employed to optimize the joint effect of drug concentration in the drug/lipid mixture, solid lipid concentration in the solid/liquid lipid mixture, and surfactant concentration in the total mixture on size and entrapment. The optimized NLCs were coated with chitosan. The nanoparticles were characterized by surface charge, spectroscopic, thermal, morphological, mucoadhesion, release, histopathological, and antifungal properties. The nanoparticles are characterized by a particle size of 335 ± 13.5 nm, entrapment efficiency of 73.1 ± 4.9%, sustained release, minor histopathological effects on rabbit oral mucosa, and higher fungal inhibition efficiency for an extended period of time compared with fluconazole solution. Coating the nanoparticles with chitosan increased its adhesion to rabbit oral buccal mucosa and improved its anti-candidiasis activity. It is concluded that mucoadhesive lipid-based nanoparticles amplify the effect of fluconazole on . This finding warrants pre-clinical and clinical studies in oral candidiasis disease models to corroborate findings.
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http://dx.doi.org/10.1080/03639045.2020.1871005DOI Listing
February 2021

Enhanced full-thickness wound healing via extract delivery based on a chitosan/gelatin dressing incorporating microemulsion.

Drug Dev Ind Pharm 2021 Feb 4;47(2):215-224. Epub 2021 Jan 4.

Department of Pharmaceutics, College of Pharmacy, Jouf University, Sakaka, Saudi Arabia.

There are many synthetic drugs in literature have been utilized in healing of the wounds although the natural product specially antioxidants can offer similar if not better biological activity in that regard. Genus Sophora is well known to contain flavonoids and phenolic compounds which have antioxidant and inflammatory effects. So, the aim of the current study was to develop and evaluate chitosan/gelatin based extract-loaded microemulsion as wound dressing. extract (SGE) contained 16 major compounds which have reasonable antioxidant activity. The developed microemulsion showed that Tween 80 produced significant ( < 0.05) lower particle size than Pluronic F127 at the same SGE concentration whereas high concentration of extract results in large particle size. Thermodynamic stability studies showed that using higher concentration of the extract produced less stable formulations. The selected formulation was impregnated in the dressing base (chitosan/gelatin; 2:1 w/w ratio) which exhibited more water absorption. evaluation revealed that the dressing displayed superior wound repair compared to the control in terms histological examination and determination of alpha smooth muscle actin (α-SMA) and proliferating cell nuclear antigen (PCNA). Thus, SGE-loaded microemulsion-impregnated gelatin/chitosan could be a potential candidate for the wound healing.
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http://dx.doi.org/10.1080/03639045.2020.1863420DOI Listing
February 2021

Improvement of Ocular Efficacy of Levofloxacin by Bioadhesive Chitosan Coated PLGA Nanoparticles: Box-behnken Design, Characterization, Antibacterial Evaluation and Scintigraphy Study.

Iran J Pharm Res 2020 ;19(1):292-311

Department of Pharmaceutics, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, India.

Conjunctivitis is considered as a common infection of ocular surfaces. Eye drop is most commonly used for treatment of conjunctivitis, but has some drawback like 95% drug eliminated after administration. Administration of levofloxacin to the anterior site in form of chitosan coated poly (lactic-co-glycolic acid) nanoparticles (LFV-CS-PLGA-NPs) expected to overcome these problem and increasing corneal contact time and permeability for effective treatment of bacterial conjunctivitis. The Nanoparticles were developed by single emulsion solvent evaporation technique and optimized for different variables (chitosan, poly (lactide-co-glycolic acid) and polyvinyl alcohol concentration) by employing three factors, three levels Box-Behnken statistical design. The nanoparticles were evaluated for particle size, drug loading, entrapment efficiency, drug release, permeation, ocular tolerance, antimicrobial study, confocal laser microscopy, and Gamma scintigraphy study. The particle size and PdI of the optimized nanoparticles were 169.968 ± 15.23 nm and 0.13 ± 0.03, respectively, where as entrapment efficiency and drug loading is 49.54 ± 2.43% and 11.29 ± 2.13% with extended release profile and strong mucoadhesion. DSC data indicated levofloxacin formed molecular dispersion within coated nanoparticles. Corneal flux showed significantly ( 0.05) higher permeation as compared to marketed formulation. Formulation was nonirritant and possessed good antibacterial activity. Gamma Scintigraphy showed slow drainage compared to drug solution, indicating reduction in nasolachrymal drainage. The Gamma Scintigraphy study indicated the CS coated PLGA-NPs have high corneal residence time as compared to drug solution. So, it is revealed that LFV-CS-PLGA-NPs increase the drug concentration over ocular tissue and potential usefulness for sustained drug delivery.
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http://dx.doi.org/10.22037/ijpr.2019.15318.13016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7462482PMC
January 2020

Role of serum Metadherin mRNA expression in the diagnosis and prediction of survival in patients with colorectal cancer.

Mol Biol Rep 2020 Apr 22;47(4):2509-2519. Epub 2020 Feb 22.

Department of Internal Medicine, Faculty of Medicine, Tanta University, Tanta, Egypt.

Early diagnosis and treatment of colorectal cancer (CRC) are important for improving patients' survival. Metadherin is an oncogene that plays a pivotal role in carcinogenesis and can be suggested as a cancer biomarker. This study aimed to elucidate the efficacy of serum Metadherin mRNA expression as a potential non-invasive biomarker for early diagnosis of CRC in relation to other screening markers as carcinoembryonic antigen (CEA), carbohydrate antigen 19.9 (CA19.9) and Fecal occult blood (FOB) and also to assess its relationship with the tumor stage and survival rate. A convenience series of 86 CRC cases (group I) were recruited with 78 subjects as controls (group II). Serum Metadherin mRNA expression level was determined using reverse transcription polymerase chain reaction (RT-PCR). Serum Metadherin mRNA expression level was significantly elevated in CRC cases when compared with controls (P < 0.001). For CRC diagnosis; Receiver operator characteristic (ROC) analyses revealed that the diagnostic accuracy of serum Metadherin mRNA (AUC = 0.976) was significantly higher than other routine CRC screening markers as CEA, CA19.9 and FOB. The combined accuracy of these markers (AUC = 0.741) was increased when used with serum Metadherin mRNA (AUC = 0.820). High serum Metadherin mRNA expression was associated with poorly differentiated histological grade, advanced tumor stage and lower survival rate. AUC of Metadherin was 0.820 for differentiating advanced versus early tumor stages. Serum Metadherin mRNA expression is a useful non-invasive biomarker for CRC. It can be used for screening and early diagnosis of CRC and can increase the efficacy of other routine CRC screening markers when it is estimated in CRC patients with them. It is also associated with advanced tumor stage and a lower survival rate.
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http://dx.doi.org/10.1007/s11033-020-05334-5DOI Listing
April 2020

Long-Acting Paliperidone Parenteral Formulations Based on Polycaprolactone Nanoparticles; the Influence of Stabilizer and Chitosan on In Vitro Release, Protein Adsorption, and Cytotoxicity.

Pharmaceutics 2020 Feb 16;12(2). Epub 2020 Feb 16.

Department of Pharmaceutics, College of Pharmacy, Jouf University, Sakakah P.O. Box 2014, Saudi Arabia.

Long-acting preparations containing the antipsychotic paliperidone for intramuscular injection has drawn considerable attention to achieve harmless long-term treatment. This study aimed to develop paliperidone loaded polycaprolactone (PCL) nanoparticles and investigate the influence of PCL/drug ratio, stabilizer type, and chitosan coating on physicochemical properties, protein adsorption, and cellular toxicity. Results showed that chitosan coating produced enlarged particle sizes, shifted the surface charges from negative into positive and did not influence encapsulation efficiencies. Chitosan coating relatively sustained the drug release especially in pluronic stabilized formulations. Pluronic F127 based formulations exhibited the least protein adsorption (384.3 μg/mL). Chitosan coating of Tween 80 and polyvinyl alcohol stabilized formulations significantly ( < 0.05) increased protein adsorption. Cellular viability was concentration-dependent and negatively affected by stabilizers. All formulations did not show cellular death at 1.56 μg/mL. Inflammatory responses and oxidative stress were less affected by Tween 80 compared with other stabilizers. Chitosan minimized all aspects of cellular toxicity. Collectively, stabilizer type and chitosan coating play critical roles in developing safe and effective long-acting PCL nanoparticles intended for parenteral drug delivery. The coated formulations containing Tween 80 and Pluronic F127 as stabilizers are warranted a future in vivo study to delineate its safety and efficacy profiles.
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http://dx.doi.org/10.3390/pharmaceutics12020160DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7076490PMC
February 2020

Predictors of poorly developed coronary collateral circulation in patients with subclinical hypothyroidism suffered from chronic stable angina.

Glob Cardiol Sci Pract 2019 Sep 20;2019(2):e201910. Epub 2019 Sep 20.

Department of Internal Medicine, Faculty of Medicine, Tanta University, Tanta, Egypt.

The development of coronary collaterals is variable among patients with coronary artery disease and remains incompletely understood. We aimed to demonstrate the predictors of poorly developed coronary collateral circulation (CCC) in patients with subclinical hypothyroidism suffered from chronic stable angina. The study was conducted on 226 patients with subclinical hypothyroidism suffered from chronic stable angina, coronary angiography documented total occlusion at any major coronary artery or coronary artery lumen diameter stenosis >90%. Patients were divided into two groups according to grade of CCC, group A: 138 patients with (good collaterals) and group B: 88 patients with (poor collaterals). To classify CCC, we used Rentrop's classification. Multivariate regression analysis was performed and identified the independent predictors of poor coronary collaterals: N/L ratio (OR 0.413, CI 95% [0.172-0.993], p = 0.048), and TSH (OR 2.511, CI 95% [1.784-3.534], p = 0.001). The ROC analysis provided a cut-off value of >4.6 for N/L ratio, and >9 µIU/mL for TSH to predict poor coronary collaterals. An elevated level of N/L ratio >4.6 and TSH level >9 µIU/mL were the independent predictors of poorly developed CCC in patients with subclinical hypothyroidism suffered from chronic stable angina.
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http://dx.doi.org/10.21542/gcsp.2019.10DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6865308PMC
September 2019

Assessment of two novel renal tubular proteins in type 2 diabetic patients with nephropathy.

J Investig Med 2020 03 12;68(3):748-755. Epub 2019 Nov 12.

Medical Biochemistry, Tanta University Faculty of Medicine, Tanta, Egypt.

Nephropathy is a common health issue associated with type 2 diabetes mellitus (T2DM). Treatment of diabetic nephropathy (DN) in an early stage can effectively inhibit its progression. Albuminuria is the currently accepted marker for detection of DN.This study aims to evaluate the urinary level of two novel renal tubular proteins (cyclophilin A and periostin) in patients with T2DM and among different nephropathy stages and also to validate the diagnostic accuracy of both cyclophilin A and periostin as potential markers for early prediction of DN relative to albuminuria.This cross-sectional study recruited 137 patients with T2DM, and they were divided based on their urinary albumin:creatinine ratio into T2DM with normoalbuminuria (), incipient T2DN with microalbuminuria () and overt T2DN with macroalbuminuria ( ) beside 41 healthy subjects as Cyclophilin A and periostin were measured in the urine using ELISA. Diagnostic accuracy of both markers was determined for prediction of DN via receiver operating characteristic curve analyses.Urinary cyclophilin A and periostin levels were significantly higher in DN groups when compared with T2DM with normoalbuminuria group. For prediction of incipient and overt DN, areas under the curve (AUCs) of periostin were 0.954, 0.997 and cyclophilin A were 0.914, 0.937, respectively. AUCs of periostin were higher than that for cyclophilin A with a significant AUC difference (p=0.022) in overt DN stage.Periostin and cyclophilin A could be regarded as a potential urinary biomarker for early prediction of DN. Periostin exhibits a higher diagnostic accuracy than urinary cyclophilin A specifically in overt DN stage.
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http://dx.doi.org/10.1136/jim-2019-001135DOI Listing
March 2020

Impact of nanostructured lipid carriers on dapsone delivery to the skin: in vitro and in vivo studies.

Int J Pharm 2019 Dec 9;572:118781. Epub 2019 Nov 9.

Department of Pharmaceutics and Ind. Pharmacy, Faculty of Pharmacy (Boys), Al-Azhar University, Nasr City, Cairo, Egypt; Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia.

The main objective of this study was to develop, characterize and evaluate the potential use of dapsone-loaded nanostructured lipid carriers (NLCs) as a topical treatment for acne. Differently charged NLC formulations were successfully prepared using an emulsification/sonication method. The particle sizes ranged from 106.2 ± 5.6 nm to 151.3 ± 7.4 nm, and the NLCs possessed the predicted surface charges, depending on the emulsifier used (Tween 80, Transcutol P, or cetyltrimethylammonium bromide). The entrapment efficiencies ranged from 76.5 ± 3.8% to 91.1 ± 3.9%. Selected formulations were assessed for possible interactions, in vitro release, ex vivo skin permeation, pharmacological efficacy and safety compared with a hydroalcoholic solution. Dapsone was embedded in the lipid matrix of NLCs and behaved as controlled release system with a good occlusive effect. Dapsone-loaded cationic NLC formulation enhanced the skin permeation of dapsone, increase the amount of dapsone retained in the skin in controlled manner, and improved the anti-rosacea activity. Based on these encouraging results, cationic NLC represents a promising carrier for the safe topical delivery of dapsone.
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http://dx.doi.org/10.1016/j.ijpharm.2019.118781DOI Listing
December 2019

Assessment of Ketamine Adult Anesthetic Doses in Pediatrics Using Pharmacokinetic Modeling and Simulations.

Pharmacotherapy 2019 04 27;39(4):454-462. Epub 2019 Mar 27.

Department of Anesthesia, School of Medicine, Stanford University, Stanford, California.

Background: Although few studies have used ketamine for induction and maintenance of pediatric anesthesia, official dosage recommendations are lacking. This study evaluates the outcomes of adult anesthetic doses in a pediatric population through pharmacokinetic modeling and computer simulations in an attempt to recommend an adequate ketamine dosing regimen.

Methods: Ketamine plasma concentration-time data in 19 children (age 8 months to 16 years; weight 5.5 to 67 kg) were analyzed according to a non-compartmental pharmacokinetic approach. The relationship between pharmacokinetic parameters and demographic covariates was mathematically characterized. A one-compartment open model was implemented to simulate the plasma profile following administration of 1-4.5 mg/kg IV bolus dose and 0.1-0.5 mg/kg/min continuous infusion of ketamine and to predict anesthesia onset and offset.

Key Results: Pharmacokinetic parameters determined were clearance 0.025 ± 0.008 L/kg/min; distribution volume 3.3 ± 1.3 L/kg; half-life 2.6 ± 1 h; and mean residence time 2.3 ± 0.64 h. Body weight was the best predictor of clearance and distribution volume according to a 0.75-power model. Using weight to scale doses was associated with limited variability in simulated concentrations. Ketamine administered as 2.25 mg/kg IV bolus dose, followed by 0.1 mg/kg/min continuous IV infusion enables anesthesia initiation within 3 minutes and maintains it for 3 hours.

Conclusions & Inferences: Weight-based dosing minimizes age-dependent variation in the plasma concentration of ketamine. Low-to-intermediate adult doses are suitable for induction and maintenance of safe anesthesia in children undergoing short-term surgical operations. However, this finding requires validation in controlled clinical trials before it is adopted into surgical standard practices.
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http://dx.doi.org/10.1002/phar.2243DOI Listing
April 2019

Soy isoflavone-loaded alginate microspheres in thermosensitive gel base: attempts to improve wound-healing efficacy.

J Pharm Pharmacol 2019 May 14;71(5):774-787. Epub 2019 Jan 14.

Department of Pharmaceutics, College of Pharmacy, Jouf University, Sakaka, Saudi Arabia.

Objectives: This study aims to develop thermosensitive gel containing soy isoflavone (antioxidant and anti-inflammatory natural agent) alginate microspheres for enhancement of wound-healing performance.

Methods: Soy isoflavone microspheres were prepared by ionic cross-linking method and optimized using the Box-Behnken optimization design. Formulations were characterized in terms of particle size, encapsulation efficiency and equilibrium swelling degree. The optimized formula was incorporated in Pluronic F127 gel base and examined for in vivo wound-healing efficacy.

Key Findings: Results showed mean particle size between 18 and 25 μm, encapsulation efficiency of over 75% and equilibrium swelling degree over 1.9. Thermal analysis indicated interaction between alginate and CaCl and embedding of soy isoflavone in microspheres. In vivo wound-healing efficacy showed significant advance in re-epithelization, mature collagen synthesis and proangiogenesis. Immunohistochemical investigation exhibited promising alpha-smooth muscle actin immunopositive cells expression, fibroblast activation and expression of proliferating cell nuclear antigen (proliferation marker) in the epidermis and in the dermis.

Conclusions: The developed formulation would appear to be a promising topical preparation for accelerating healing process.
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http://dx.doi.org/10.1111/jphp.13066DOI Listing
May 2019

Multifunctional carbamazepine loaded nanostructured lipid carrier (NLC) formulation.

Int J Pharm 2018 Oct 1;550(1-2):359-371. Epub 2018 Sep 1.

Department of Anatomy and Embryology, Faculty of Medicine, Ain Shams University, Cairo, Egypt; Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, P.O. Box 2014, Skaka, Saudi Arabia.

Carbamazepine is a valuable pharmacological agent prescribed in treatment of epilepsy and trigeminal neuralgia. Poor bioavailability, successive dose adjustments and reported long term toxic effects are the main hurdles associated with carbamazepine oral administration. Bees wax containing NLC formulations were developed using high shear homogenization/sonication technique to overcome drug limitations. Formulations were successfully produced and evaluated for both in vitro and in vivo assessments. Results showed particles in nanometric range with negative surface charge and satisfying encapsulation efficiencies (from 93.1 ± 7.6 to 95.7 ± 5.6%). In vitro release studies revealed biphasic pattern and faster release was accompanied with higher bees wax concentration. Interaction between drug and NLC components was assessed using infrared and thermal analysis. Using validated chromatographic analytical method, selected formulation showed good pharmacokinetic profile depriving from plasma fluctuation with 2.27-fold and 1.83-fold improved bioavailability compared to conventional drug suspension and Tegretol™ suspension respectively. It also showed stronger anticonvulsant activity, with respect to conventional drug suspension, in terms of seizure latency, frequency and duration. Toxicity studies revealed undetectable liver or testicular toxicity in biochemical, histological and immunohistochemical investigations verifying its superiority above other investigated formulations. Collectively, results indicate potential suitability of NLC system to effectively and safely deliver carbamazepine orally.
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http://dx.doi.org/10.1016/j.ijpharm.2018.08.062DOI Listing
October 2018

Atorvastatin-loaded nanostructured lipid carriers (NLCs): strategy to overcome oral delivery drawbacks.

Drug Deliv 2017 Nov;24(1):932-941

a Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy , Al-Azhar University , Cairo , Egypt.

Atorvastatin (AT) is a widely used lipid-regulating drug to reduce cholesterol and triglycerides. Its poor aqueous solubility and hepatic metabolism require development of drug delivery systems able to improve its solubility and bypass hepatic effect. For this purpose, atorvastatin nanostructured lipid carriers (AT-NLCs) were prepared and characterized. AT-NLCs were prepared by emulsification using high-speed homogenization followed by ultrasonication. The prepared NLCs showed particle size between 162.5 ± 12 and 865.55 ± 28 nm while zeta potential values varied between -34 ± 0.29 and -23 ± 0.36 mV. They also showed high encapsulation efficiency (>87%) and amorphous state of the drug in lipid matrix. Pharmacokinetic parameters of optimized formulation (NLC-1; composed of 2% Gelucire 43/01, 8% Capryol PGMC, 2% PluronicF68 and 0.5% lecithin) revealed 3.6- and 2.1-fold increase in bioavailability as compared to atorvastatin suspension and commercial product (Lipitor), respectively. Administration of NLC-1 led to significant reduction (p < .05) in the rats' serum levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL) and significant increase in high-density lipoprotein (HDL). This improvement was confirmed histologically by minimizing the associated hepatic steatosis. These investigations demonstrated the superiority of NLCs for improvement of oral bioavailability and in vivo performance of AT.
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http://dx.doi.org/10.1080/10717544.2017.1337823DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8241136PMC
November 2017

Influence of the flexible liposomes on the skin deposition of a hydrophilic model drug, carboxyfluorescein: dependency on their composition.

ScientificWorldJournal 2012 12;2012:134876. Epub 2012 Mar 12.

Department of Pharmaceutics, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia.

This study focuses on the effect of different flexible liposomes containing sodium cholate, Tween 80, or cineol on skin deposition of carboxyfluorescein (CF). Size distribution, morphology, zeta potential, and stability of the prepared vesicles were evaluated. The influence of these systems on the skin deposition of CF utilizing rat skin as membrane model was investigated. Results showed that all of the investigated liposomes had almost spherical shapes with low polydispersity (PDI < 0.3) and particles size range from 83 to 175 nm. All liposomal formulations exhibited negative zeta potential, good drug entrapment efficiency, and stability. In vitro skin deposition data showed that flexible liposomes gave significant deposition of CF on the skin compared to conventional liposomes and drug solutions. This study revealed that flexible liposomes, containing cineole, were able to deliver higher amount of CF suggesting that the hydrophilic drugs delivery to the skin was strictly correlated to the vesicle composition.
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http://dx.doi.org/10.1100/2012/134876DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3334324PMC
July 2012

Relaxing retinotomies and retinectomies in the management of retinal detachment with severe proliferative vitreoretinopathy (PVR).

Clin Ophthalmol 2010 Oct 5;4:1107-14. Epub 2010 Oct 5.

Opthamology Department, Al-Azhar University, Cairo, Egypt; Chief Vitreoretinal Service, Dr Soliman Fakeeh Hospital, Jeddah, Saudi Arabia.

Unlabelled: Relaxing retinotomies and retinectomies are used in the presence of retinal shortening resulting from retinal incarceration or fibrous proliferation and contraction that prevents contact of the retina with the retinal pigment epithelium. The peripheral retina is usually cut or excised to preserve function of the posterior retina which is more visually significant.

Objective: To investigate the techniques, therapeutic effects, indications, and complications of relaxing retinotomies and retinectomies for complicated retinal detachment with severe proliferative vitreoretinopathy (PVR).

Methods: Thirty eight eyes of 38 patients of complicated retinal detachment with severe PVR were recruited for a noncomparative retrospective study. They were operated on and followed-up for at least six months. The operative technique included buckling, vitrectomy, peeling, relaxing retinotomy and/or retinectomy, intraocular tamponade, and laser treatment.

Results: Retina was reattached in 34 (89.5%) eyes in operations. Retinal detachment was recurrent in seven eyes in follow-up, in which the retina was reattached again in two eyes by a second operation. The final success rate was 76.3% (29 eyes out of 38 eyes). Visual acuity was perception of light with bad projection in 35 (92%) eyes and hand motion in three (8%) eyes before operation. Visual acuity was better than 4/60 in 23 eyes (60.5%) after operation. The complications included iatrogenic retinal breaks, bleeding from the retinotomy site, hypotony, and recurrent fibrous proliferation from the retinotomy site.

Conclusion: Retinotomy and retinectomy can improve the curative effect of complicated retinal detachment. There are potentially serious complications of these maneuvers and they should not be performed if less aggressive measures will suffice.
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http://dx.doi.org/10.2147/OPTH.S4934DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2952612PMC
October 2010
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