Khaled Almansour

Dr. Khaled Almansour

orcid

Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
1 July 2015 in Journal of Controlled Release
Verified
Journal Article
Open access
ATAlistair Taverner
Alistair Taverner
RDRuggero Dondi
Ruggero Dondi
KAKhaled Almansour
Khaled Almansour
FLFloriane Laurent
Floriane Laurent
SOSiân-Eleri Owens
Siân-Eleri Owens
RMRandall J. Mrsny
Randall J. Mrsny
The intestinal epithelium functions to effectively restrict the causal uptake of luminal contents but has been demonstrated to transiently increase paracellular permeability properties to provide an additional entry route for dietary macromolecules. We have examined a method to emulate this endogenous mechanism as a means of enhancing the oral uptake of insulin. Two sets of stable Permeant Inhibitor of Phosphatase (PIP) peptides were rationally designed to stimulate phosphorylation of intracellular epithelial myosin light chain (MLC) and screened using Caco-2 monolayers in vitro. Apical application of PIP peptide 640, designed to disrupt protein-protein interactions between protein phosphatase 1 (PP1) and its regulator CPI-17, resulted in a reversible and non-toxic transient reduction in Caco-2 monolayer trans-epithelial electric resistance (TEER) and opening of the paracellular route to 4kDa fluorescent dextran but not 70kDa dextran in vitro. Apical application of PIP peptide 250, designed to impede MYPT1-mediated regulation of PP1, also decreased TEER in a reversible and non-toxic manner but transiently opened the paracellular route to both 4 and 70kDa fluorescent dextrans. Direct injection of PIP peptides 640 or 250 with human insulin into the lumen of rat jejunum caused a decrease in blood glucose levels that was PIP peptide and insulin dose-dependent and correlated with increased pMLC levels. Systemic levels of insulin suggested approximately 3-4% of the dose injected into the intestinal lumen was absorbed, relative to a subcutaneous injection. Measurement of insulin levels in the portal vein showed a time window of absorption that was consistent with systemic concentration-time profiles and approximately 50% first-pass clearance by the liver. Monitoring the uptake of a fluorescent form of insulin suggested its uptake occurred via the paracellular route. Together, these studies add validation to the presence of an endogenous mechanism used by the intestinal epithelium to dynamically regulate its paracellular permeability properties and better define the potential to enhance the oral delivery of biopharmaceuticals via a transient regulation of an endogenous mechanism controlling the intestinal paracellular barrier.

11 December 2021 in Microorganisms
Verified
Journal Article
Open access
PDF file
MAMomen Askoura
Momen Askoura
AAAhmad Almalki
Ahmad Almalki
ALAmr Abu Lila
Amr Abu Lila
KAKhaled Almansour
Khaled Almansour
FAFarhan Alshammari
Farhan Alshammari
Wael HegazyWael Hegazy
Wael Hegazy
Salmonella enterica is a common cause of many enteric infections worldwide and is successfully engineered to deliver heterologous antigens to be used as vaccines. Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs) RNA-guided Cas9 endonuclease is a promising genome editing tool. In the current study, a CRISPR-Cas9 system was used to target S.enterica sdiA that encodes signal molecule receptor SdiA and responds to the quorum sensing (QS) signaling compounds N-acylhomoserine lactones (AHLs). For this purpose, sdiA was targeted in both S.enterica wild type (WT) and the ΔssaV mutant strain, where SsaV has been reported to be an essential component of SPI2-T3SS. The impact of sdiA mutation on S. enterica virulence was evaluated at both early invasion and later intracellular replication in both the presence and absence of AHL. Additionally, the influence of sdiA mutation on the pathogenesis S. enterica WT and mutants was investigated in vivo, using mice infection model. Finally, the minimum inhibitory concentrations (MICs) of various antibiotics against S. enterica strains were determined. Present findings show that mutation in sdiA significantly affects S.enterica biofilm formation, cell adhesion and invasion. However, sdiA mutation did not affect bacterial intracellular survival. Moreover, in vivo bacterial pathogenesis was markedly lowered in S.enterica ΔsdiA in comparison with the wild-type strain. Significantly, double-mutant sdiA and ssaV attenuated the S. enterica virulence and in vivo pathogenesis. Moreover, mutations in selected genes increased Salmonella susceptibility to tested antibiotics, as revealed by determining the MICs and MBICs of these antibiotics. Altogether, current results clearly highlight the importance of the CRISPR-Cas9 system as a bacterial genome editing tool and the valuable role of SdiA in S.enterica virulence. The present findings extend the understanding of virulence regulation and host pathogenesis of Salmonellaenterica.

3 January 2022 in Pathogens
Verified
Journal Article
Open access
PDF file
MAMomen Askoura
Momen Askoura
Abbas Hisham AAbbas Hisham A
Abbas Hisham A
HSHadeel Al Sadoun
Hadeel Al Sadoun
WAWesam Abdulaal
Wesam Abdulaal
ALAmr Abu Lila
Amr Abu Lila
Wael HegazyWael Hegazy
Wael Hegazy
Hepatitis C virus (HCV) is one of the most epidemic viral infections in the world. Three-quarters of individuals infected with HCV become chronic. As a consequence of persistent inflammation, a considerable percentage of chronic patients progress to liver fibrosis, cirrhosis, and finally hepatocellular carcinoma. Cytokines, which are particularly produced from T-helper cells, play a crucial role in immune protection against HCV and the progression of the disease as well. In this study, the role of interleukins IL-33, IL-17, and IL-25 in HCV patients and progression of disease from chronicity to hepatocellular carcinoma will be characterized in order to use them as biomarkers of disease progression. The serum levels of the tested interleukins were measured in patients suffering from chronic hepatitis C (CHC), hepatocellular carcinoma (HCC), and healthy controls (C), and their levels were correlated to the degree of liver fibrosis, liver fibrosis markers and viral load. In contrast to the IL-25 serum level, which increased in patients suffering from HCC only, the serum levels of both IL-33 and IL-17 increased significantly in those patients suffering from CHC and HCC. In addition, IL-33 serum level was found to increase by liver fibrosis progression and viral load, in contrast to both IL-17 and IL-25. Current results indicate a significant role of IL-33 in liver inflammation and fibrosis progress in CHC, whereas IL-17 and IL-25 may be used as biomarkers for the development of hepatocellular carcinoma.

27 January 2022 in Polymers
Verified
Journal Article
Open access
PDF file
MAMarwa H. Abdallah
Marwa H. Abdallah
ALAmr Abu Lila
Amr Abu Lila
SSSeham Mohammed Shawky
Seham Mohammed Shawky
KAKhaled Almansour
Khaled Almansour
FAFarhan Alshammari
Farhan Alshammari
TMTarek Makram
Tarek Makram
Current advancements in the research investigations focused at using natural products to generate novel dosage forms with a potential therapeutic impact. Silymarin is a natural product obtained from the herb Silybum marianum that has been shown to have remarkable hypoglycemic activity. Owing to the low enteral absorption, instability in stomach secretion, and poor solubility of Silymarin, it was better to be produced as a topical dosage form. A three-factor, three-level Box Behnken (33 BB) design was constructed to develop 15 formulations using three independent variables (phospholipid concentration, surfactant concentration, and sonication time) and two dependent variables (encapsulation efficiency and in vitro drug release). The optimized formula was added to HPMC gel and the resulting transfersomal gel was investigated for its characteristics, in vitro, ex vivo and hypoglycemic behaviors. The pH of the Silymarin-loaded transfersomal gel was 7.05, the spreadability was 55.35 mm, and the viscosity was 6.27 Pa. Furthermore, Silymarin loaded transfersomal gel had the greatest transdermal flux (92.41 µg/cm2·h), which was much greater than all other formulations. In vivo observations revealed that Silymarin loaded transfersomal gel significantly reduced blood glucose levels, compared to either Silymarin gel or oral Silymarin suspension. The findings show that the developed transfersomal gel could be an effective carrier for Silymarin transdermal delivery.

6 April 2022 in Pharmaceutics
Verified
Journal Article
Open access
PDF file
KAKhaled Almansour
Khaled Almansour
RARAISUDDIN ALI
RAISUDDIN ALI
FAFawaz Nasser Alheibshy
Fawaz Nasser Alheibshy
TATariq J. Almutairi
Tariq J. Almutairi
RARakan F. Alshammari
Rakan F. Alshammari
MEMustafa M.A. Elsayed
Mustafa M.A. Elsayed
Nano spray drying has emerged as an outstanding platform for engineering micro- and nanoparticles, with growing applications in various areas of drug delivery. As a new technology involving distinct technical design, parameters of the nano spray drying process are not fully elucidated. In a quality-by-design approach, the aim of the current study was to gain thorough understanding of critical determinants of product characteristics in the Büchi Nano Spray Dryer B-90. Following a factorial experimental design, a series of spray drying experiments were conducted to gain new insights into the influences of the inlet temperature, the spray solvent, and the solute concentration in the spray solution on the yield, the moisture content, and the particle size of the nano spray-dried powder material. Special consideration was given to the potential of using hydroethanolic in comparison with aqueous solvent systems and to particle engineering for pulmonary drug delivery. Lactose and mannitol, widely used as excipients in dry powder inhalation formulations, were used as model materials. Lactose and mannitol are known to spray dry in amorphous and crystalline forms, respectively. The yields of spray drying of lactose and mannitol amounted generally to 71.1 ± 6.6% w/w and 66.1 ± 3.5% w/w, respectively. The spray-dried materials exhibited generally a number-weighted median particle diameter of 1.6 ± 0.2 μm and a volume-weighted median particle diameter of 5.1 ± 1.0 μm. A detailed analysis of the results improved understanding of the interplay between process parameters in the Nano Spray Dryer. The results demonstrate that optimization of spray generation is the key to yield optimization. On the other hand, particle size is determined by the spray mesh pore size and the spray solution degree of saturation. Selection of an appropriate spray solvent and using spray solution additives could optimize spray flow. In parallel, the spray solvent and the solute concentration in the spray solution determine the degree of saturation. Guidance on optimization of particle engineering by nano spray drying is provided.

18 November 2021 in Gels
Verified
Journal Article
Open access
PDF file
MAMarwa H. Abdallah
Marwa H. Abdallah
HEHeba Elsewedy
Heba Elsewedy
ALAmr Abu Lila
Amr Abu Lila
KAKhaled Almansour
Khaled Almansour
RURahamat Unissa
Rahamat Unissa
MSMahmoud S. Soliman
Mahmoud S. Soliman
One of the recent advancements in research is the application of natural products in developing newly effective formulations that have few drawbacks and that boost therapeutic effects. The goal of the current exploration is to investigate the effect of jojoba oil in augmenting the anti-inflammatory effect of Brucine natural alkaloid. This is first development of a formulation that applies Brucine and jojoba oil int a PEGylated liposomal emulgel proposed for topical application. Initially, various PEGylated Brucine liposomal formulations were fabricated using a thin-film hydration method. (22) Factorial design was assembled using two factors (egg Phosphatidylcholine and cholesterol concentrations) and three responses (particle size, encapsulation efficiency and in vitro release). The optimized formula was incorporated within jojoba oil emulgel. The PEGylated liposomal emulgel was inspected for its characteristics, in vitro, ex vivo and anti-inflammatory behaviors. Liposomal emulgel showed a pH of 6.63, a spreadability of 48.8 mm and a viscosity of 9310 cP. As much as 40.57% of Brucine was released after 6 h, and drug permeability exhibited a flux of 0.47 µg/cm2·h. Lastly, % of inflammation was lowered to 47.7, which was significant effect compared to other formulations. In conclusion, the anti-inflammatory influence of jojoba oil and Brucine was confirmed, supporting their integration into liposomal emulgel as a potential nanocarrier.