Riham Bakr

Dr. Riham Bakr

orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

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

Representative Publications

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1 July 2016 in Revista Brasileira de Farmacognosia
Verified
Journal Article
Open access
RBRiham Bakr
Riham Bakr
MBMahitab El Bishbishy
Mahitab El Bishbishy
The present study was designed to investigate polyphenolic and sulphur contents of the aerial parts of Capparis spinosa var. aegyptia (Lam.) Boiss., Capparaceae, wildly growing in Egypt. The chemical compositions of the water distilled essential oil were investigated by GC/MS analysis where the major constituent of the oil was methyl isothiocyanate (24.66%). Hydroethanolic extract was evaluated by LC-HRESI-MS–MS in both positive and negative modes. Forty-two compounds were identified including quercetin, kaempferol and isorhamnetin derivatives in addition to myricetin, eriodictyol, cirsimaritin and gallocatechin derivatives. Quercetin tetrahexoside dirhamnoside as well as kaempferol dihexoside dirhamnoside have not been identified before in genus Capparis. Phenolic acids, such as quinic acid, p-coumaroyl quinic acid and chlorogenic acid were also identified. Evaluation of cytotoxic activity of hydroethanolic extract against three human cancer cell lines (MCF-7; breast adenocarcinoma cells, Hep-G2; hepatocellular carcinoma cells and HCT-116; colon carcinoma) using 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay showed significant effect with IC50 values 24.5, 24.4 and 11μg/ml, compared to Doxorubicin as a standard cytotoxic drug. C. spinosa revealed itself as a promising candidate for nutraceutical researches

14 April 2020 in Scientific Reports
Verified
Journal Article
Open access
PDF file
RBRiham Bakr
Riham Bakr
GEGhada H. El-Osaily
Ghada H. El-Osaily
RBRiham O. Bakr
Riham O. Bakr
RDRiham Salah El Dine
Riham Salah El Dine
AFAhmed M. Fayez
Ahmed M. Fayez
Skin health is vital for a healthy body. Herbal remedies have long been used for skin care, and their global use has tremendously increased over the past three decades. Although cellulite is seen as a normal condition by the medical community, it is considered a serious cosmetic concern for most affected women. Many topical anti-cellulite creams are available on the market, but unfortunately, their efficacy has not been proven scientifically. Microneedles (MNs) represent a new approach to enhance the permeation of loaded medication through the skin. In this study, the anti-cellulite effects of Vitex agnus-castus and Tamarindus indica extracts were compared using safe and effective polymeric MNs. This delivery system offers a painless alternative to the combined treatment strategy of microneedling devices and anti-cellulite products. The selected standardized extracts were evaluated for their mineral, phenolic and flavonoid contents, which are correlated to a promising antioxidant effect, as demonstrated by an in vitro radical scavenging activity assay. 3D-printing techniques were chosen for fabrication of a micromold, which is inexpensive for mass production. To ensure that MNs were sufficiently strong to perforate the skin without breaking, axial failure force was measured using a micro-mechanical test machine. The anticellulite effects of MNs were assessed using an in vivo diet-induced obesity guinea pig model. Skin properties, histopathology and inflammatory markers were examined. MNs loaded with plant extracts were statistically comparable in normalizing the oxidative state and reducing inflammation, while myeloperoxidase levels were more significantly reduced by T. indica than by V. agnus-castus. This novel delivery system opens the door for new transdermal strategies for cellulite management.

1 March 2021 in Biomedicine & Pharmacotherapy
Verified
Journal Article
Open access
RBRiham Bakr
Riham Bakr
RAReham I. Amer
Reham I. Amer
DADalia Attia
Dalia Attia
MAMai M. Abdelhafez
Mai M. Abdelhafez
AAAsmaa K. Al-Mokaddem
Asmaa K. Al-Mokaddem
SGSameh S. Gad
Sameh S. Gad
Many researches have been undergone to hasten the natural wound healing process. In this study, several Hibiscus species (leaves) were extracted with petroleum ether, methanol, and their mucilage was separated. All the tested species extracts were assessed for their viability percentage using the water-soluble tetrazolium. H.syriacus was the plant of choice to be incorporated in a new drug delivery system and evaluated for its wound healing activity. H.syriacus petroleum ether extract (PEE) showed a high percentage of palmitic and oleic acids while its mucilage demonstrated high glucosamine and galacturonic acid. It was selected to be formulated and pharmaceutically evaluated into three different composite sponges using chitosan in various ratios. Fourier-transformed infrared spectroscopy investigated the chemical interaction between the utilized sponges' ingredients. Morphological characteristics were evaluated using scanning electron microscopy. H.syriacus composite sponge of mucilage: chitosan (1:5) was loaded with three different concentrations of PEE. Medicated formulations were assessed in rat model of excision wound model. The wound healing ability was clearly proved by the clinical acceleration, histopathological examination, and modulation of correlated inflammatory parameters as tumor necrosis factor in addition to vascular endothelial growth factor suggesting a promising valuable candidate that supports the management of excision wounds using single-dose preparation.

17 January 2017 in Chemistry & Biodiversity
Verified
Journal Article
Closed access
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ESEsraa A. Shahat
Esraa A. Shahat
RBRiham Bakr
Riham Bakr
OEOmayma A. Eldahshan
Omayma A. Eldahshan
NANahla Ayoub
Nahla Ayoub

1 October 2019 in Colloids and Surfaces B: Biointerfaces
Verified
Journal Article
Closed access
EMEman Mostafa
Eman Mostafa
MFMarwa A.A. Fayed
Marwa A.A. Fayed
RRRasha A. Radwan
Rasha A. Radwan
RBRiham Bakr
Riham Bakr

29 September 2016 in African Journal of Traditional, Complementary and Alternative Medicines
Verified
Journal Article
Open access
PDF file
RBRiham Bakr
Riham Bakr
SMShaza Abd El Halim Mohamed
Shaza Abd El Halim Mohamed
NANahla Ayoub
Nahla Ayoub
Background: Centaurea aegyptiaca L (Asteraceae), is one of the most attractive plants growing wildly in Sinai, and is not well investigated for its phytochemical constituents. This study represents the first in-depth characterization of the phenolic profile of the aerial parts of C. aegyptiaca methanolic extract utilizing liquid chromatography (LC) combined with electrospray ionization (ESI) tandem mass spectrometry (MS/MS). Material and Methods: Phenolic profile was researched utilizing LC-HRESI-MS-MS. Assessment of cytotoxic activity against four human cancer cell lines (Hep-G2; hepatocellular carcinoma cells, MCF-7; breast adenocarcinoma cells, and HCT-116; colon carcinoma and HELA; cervical carcinoma cells) was performed using 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Antiviral activity was surveyed utilizing cytopathic effect inhibition assay. Results: A total of sixty-one compounds were tentatively distinguished (twenty-one phenolic acids and their derivatives, thirty-one flavonols and nine flavones) in the negative and positive modes. Centaurea aegyptiaca demonstrated outstanding results against Hep-G2, MCF-7, HCT-116 and HELA cell lines with IC50 of 12.1, 30.9, 11.7 and 19.5 μg/mL respectively compared and doxorubicin as a reference drug. Weak antiviral activity was seen against hepatitis A virus (HAV) and no impact against herpes simplex virus type 1 (HSV 1). Conclusion: This study provides a better understanding of the chemistry of C. aegyptiaca that announces itself as a promising cytotoxic agent.