2024-03-29T09:15:09Z
https://ejbbe.journals.ekb.eg/?_action=export&rf=summon&issue=1713
Egyptian Journal of Biomedical Engineering and Biophysics
Egypt. J. Biophys. Biomed. Engng.
1110-8525
1110-8525
2017
18
1
In vitro Study of Novel Organic/ Inorganic Composite Scaffold for Bone Regeneration
Khairy
Tohamy
Islam
Soliman
Mostafa
Mabrouk
Mohamed
Aboelnasr
In this study, polysaccharide polymers /Hydroxyapatite composite scaffolds were prepared by using freeze-drier processing technique. The microstructure and morphology as well as mechanical strength of the scaffolds were characterized by XRD, FTIR, SEM, EDX, and other methods. The porosity ratio and in vitro biomineralization of the scaffold were also evaluated. It was found that, both porosity and compressive strength are strongly dependent on the concentration of HA. The porosity was reduced from ≈ 87 ±5.1% to 66.7±3.2%, while the mechanical measurements revealed that, the compressive strength reaches the highest value 23.96±0.82 MPa by adding HA to hybrid polymers. In addition, Blended hydroxyethylcellulose to sodium alginate cause increase of total pore volume inside scaffold, decrease in mechanical properties and the presence of bioceramic inside scaffolds structure enhances the precipitation and biomineralization of HA from SBF on scaffolds surface. Thus results suggest that these biocompatible composite scaffolds can be useful for bone tissue regeneration.
Polysaccharide
Hydroxyapatite
Alginates
SBF
2017
12
01
1
12
https://ejbbe.journals.ekb.eg/article_4719_639513f5a14ce69940f9cf2cac027145.pdf
Egyptian Journal of Biomedical Engineering and Biophysics
Egypt. J. Biophys. Biomed. Engng.
1110-8525
1110-8525
2017
18
1
Controlling the Features of Electrospun Nanofibers
Mohamed
El gohary
Aziza
Elsaied
Bothaina
Abdermoneam
Ahlam
Elrashiedy
Safaa
Saleh
The major challenge of the electrospinning process lies in the optimization of its parameters to achieve desirable nanofibers morphology and properties. The present work highlights the change of properties for electrospun poly ɛ-caprolactone and poly ethylene oxide with modulation of different parameters. The effect of solution parameters such as; concentration poly ɛ-caprolactone, concentration of poly ethylene oxide relative to poly ɛ-caprolactone, viscosity , different solvents, voltage properties and distance separates tip of the syringe and collector to fabricate poly ɛ-caprolactone electrospun nanofibers with desired morphologies is indicated in present work. Morphologies of the processed nanofibers are examined by FESEM, the average diameter of nanofibers and their normal distribution are investigated by image j analyzer software. Of all combinations, the best and the finest nanofibers are obtained at 10%w\v poly ɛ-caprolactone, 3% w\v poly ethylene oxide concentration with respect to that of poly ɛ-caprolactone, at voltage 20 kV and lastly at 12 cm distance separates the tip of syringe and collector.
Electrospinning
Nanofibers
poly ɛ-caprolactone
poly ethylene oxide
2017
12
01
13
21
https://ejbbe.journals.ekb.eg/article_6325_d7dd1fed63f8061a835afbd3099035f3.pdf
Egyptian Journal of Biomedical Engineering and Biophysics
Egypt. J. Biophys. Biomed. Engng.
1110-8525
1110-8525
2017
18
1
Validation of the Octavius 4D Measuring System in Verifying Advanced External Beams Radiotherapy Techniques
Noha
Salem
The development of advanced techniques as Intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) are characterized by their numerous steep dose gradient using the dynamic MLC modality and these requires specific quality assurance (QA) to meet this complexity. The conventional dosimetery techniques, such as ionization chamber, point dose measurements and film dosimetry, are gradually being replaced by detector arrays which can produce accurate results immediately. There are many commercial detector arrays one of them is 2D-ARRAY seven29 (PTW, Freiburg, Germany). We used the Octavius 4 D measuring system with its detector array, ionization chamber. The accuracy of the synchronizing motion of the phantom was validated. It was found that the detector array response is stable after warming up with 800 MU, the dose rate measurements and the dose response is linear with R2=0.929. The gamma index for the clinical IMRT plans were found to be 93.3%, 98.0 %, 95.5% and 96.2% for head and neck, prostate, breast and brain cases, and for VMAT plans are 96.3%, 99.4 %, 98.1% and 98.6% for head and neck, prostate, breast and brain, respectively, using gamma criteria 3%/3 mm. The aim of this work is to characterize and validate the Octavius 4D measuring system for 6MV beams. Also, to verify clinical IMRT and VMAT plans, the volumetric dose matrix of the clinical plans, dose line profiles and to study the factors affect the gamma index.
Octavius 4D
arrays
verification
synchronizing
gamma
2017
12
01
22
35
https://ejbbe.journals.ekb.eg/article_6326_2ef5f5fadfd90f1297404e59a6e8e8af.pdf
Egyptian Journal of Biomedical Engineering and Biophysics
Egypt. J. Biophys. Biomed. Engng.
1110-8525
1110-8525
2017
18
1
Influence of Nanocomposite Scaffolds Using Freeze-drying Technique on Hepg2
Mohamed Ismail
El gohary
Gehan Mohamed
Kamal
Emad
El-Meliegy
Sahar
Awad
Asmaa
El-tohamy
Novel approaches are devoted towards creating 3D scaffolds that allow good permeability and diffusion. Appropriate synthetic biodegradable materials for this purpose are biopolymer- bioceramic nanocomposites. They have good tissue compatibility and safety profiles seem essential for their successful utilization in medical applications. The 3D dicalcium phosphate/dextran/ sodium carboxymethyl cellulose nanocomposites are prepared by freeze-drying method. In the present work, the physico-chemical properties of scaffolds are evaluated by XRD and FTIR. The interior morphology as well as porous structure are evaluated by scanning electron microscope (SEM). The porosity of scaffolds examined by mercury intrusion porosimetry (MIP). In addition to compressive stress parameter is also determined by Instron Industrial Product,(Model 3345;Norwood, MA, USA).The respective nanocomposite scaffolds are tested for in vitro Hepg2 cancer cytotoxicity. The nanocomposite scaffolds exhibit good biocompatibility and exerts no toxic effect on Hepg2 liver cancer cell. Therefore, the prepared porous system of nanocomposite scaffolds can be considered as promising technique for tissue engineering.
Dicalcium phosphate
Dextran
Nanocomposite
3D Scaffold
2017
12
01
36
45
https://ejbbe.journals.ekb.eg/article_7431_b4b13a86a5f0dcdda226e8664d9d85d6.pdf
Egyptian Journal of Biomedical Engineering and Biophysics
Egypt. J. Biophys. Biomed. Engng.
1110-8525
1110-8525
2017
18
1
Efficiency of Photodynamic Therapy and Avastin in Treatment of Corneal Neovascularization in Rabbit's Eye
Mohamed Ismail
El gohary
Salwa
Abdelkawi
Aziza
Hassan
Ahmed
Saif
Ayman
El Shinawy
The aim of the present work is to evaluate the effect of photodynamic therapy (PDT) by using argon laser with rose bengal (Herbs) as a photosensitizer when compared to the Avastin for treatment of corneal neovascularization (CNV) in rabbits. Thirty-Nine New Zealand male rabbits aged 2.5 months and weighing 2.5-3 kg are selected from the animal house of research institute of ophthalmology, Giza, Egypt. Three rabbits are used as control, and 36 rabbits are subjected to corneal neovascularization (CNV) induced by 3 silk sutures at mid-stromal depth approximately 1 mm from the limbus. After four days, sutures are removed and slit lamp examinations are performed to determine the area of CNV. Rabbits with CNV are divided into 3 groups: (1) The first group left without any treatment(n=12); (2) The second group (n=12 rabbits) were generally anesthetized and rose bengal(C20H4Cl4I4O5) with a dose of 50 mg/Kg was administered by slow intravenous injection in the marginal ear vein. After 15 minutes, rabbit’s eyes were exposed to argon laser(Quantel-Medical, Vitra, France) in a pulsed mode at 532 nm, spot size of 50 μm, pulse duration of 0.2 ms and a power of 150-200 mW/cm 2.; (3) The third group are treated with subconjunctival injection of 25 mg Avastin (n=12). The rabbits are followed up for 4 weeks and 3 rabbits are selected and sacrificed weekly from each group. The corneas are isolated for determination of protein content, SDS-poly acrylamide gel electrophoresis, total antioxidant capacity (TAC) and total oxidative capacity (TOC). Final results show that avastin is almost as effective as photodynamic therapy.
Corneal neovascularization (CNV)
Photodynamic therapy (PDT)
argon laser
Avastin
2017
12
01
46
55
https://ejbbe.journals.ekb.eg/article_7432_b68a227a1f62646318e3d2b242c15b64.pdf
Egyptian Journal of Biomedical Engineering and Biophysics
Egypt. J. Biophys. Biomed. Engng.
1110-8525
1110-8525
2017
18
1
Effect of Blue and Green Light Emitting Diode (LED) on Rat's Retina.
Mohamed Ismail
El gohary
Amal
El awady
Tamer
Mahmoud
Mona
Gamal
Mostafa
Abu ghazala
Our eyes are increasingly exposed to light from the light emitting diode (LED) of video display terminals (VDT) which contain much blue light. VDTs are equipped with televisions, personal computers, and smartphones.; hence it is so important to know the implications of LED radiations on the human visual system. The present study is designed to evaluate the influence of blue and green LEDs on rat's retina. Forty-six female Wistar albino rats weighing 250-300 g classified into 3 groups. Group (1) served as control. Group (II) exposed to (461nm) blue LED (12 hr light-dark cycle) for 3, 7, 14 and 21days. Group (III) exposed to (525.9 nm) green LED (12 hr light-dark cycle) for 3, 7, 14 and 21days. At the end of each period, electroretinogram (ERG) and microscopic examination are carried out. The results indicated that there was no significant effect for the green LED on the ERG, and microscopic examination illustrates mild changes. After exposure of rat's retina to blue LED, there is a reduction in a- and b- wave amplitudes, and the histopathological examination illustrates severe changes. The data suggest that the blue LED may cause retinal toxicity. Therefore, it is very important to recognize the hazard of LED radiations that affects vision and take appropriate precautions for the eye safetyKeywords: Light emitting diodes, Electroretinogram, histopathological examination.
Light emitting diodes
Electroretinogram
Histopathological examination
2017
12
01
56
66
https://ejbbe.journals.ekb.eg/article_7433_81e2780a87a032edde003b3b7c21cc22.pdf