Enface Thickness Mapping and Reflectance Imaging of Retinal Layers in Diabetic Retinopathy

Purpose

To present a method for image segmentation and generation of enface thickness maps and reflectance images of retinal layers in healthy and diabetic retinopathy (DR) subjects.

Methods

High density spectral domain optical coherence tomography (SDOCT) images were acquired in 10 healthy and 4 DR subjects. Customized image analysis software identified 5 retinal cell layer interfaces and generated thickness maps and reflectance images of the total retina (TR), inner retina (IR), outer retina (OR), and the inner segment ellipsoid (ISe) band. Thickness maps in DR subjects were compared to those of healthy subjects by generating deviation maps which displayed retinal locations with thickness below, within, and above the normal 95% confidence interval.

Results

In healthy subjects, TR and IR thickness maps displayed the foveal depression and increased thickness in the parafoveal region. OR and ISe thickness maps showed increased thickness at the fovea, consistent with normal retinal anatomy. In DR subjects, thickening and thinning in localized regions were demonstrated on TR, IR, OR, and ISe thickness maps, corresponding to retinal edema and atrophy, respectively. TR and OR reflectance images showed reduced reflectivity in regions of increased thickness. Hard exudates appeared as hyper-reflective spots in IR reflectance images and casted shadows on the deeper OR and ISe reflectance images. The ISe reflectance image clearly showed the presence of focal laser scars.

Conclusions

Enface thickness mapping and reflectance imaging of retinal layers is a potentially useful method for quantifying the spatial and axial extent of pathologies due to DR.     

Expression of TGF-β3 in isolated fibroblasts from foreskin

Background:

The multifunctional transforming growth factor beta (TGF-β) is a glycoprotein that exists in three isoforms. TGF-β3 expression increases in fetal wound healing and reduces fibronectin and collagen I and III deposition, and also improves the architecture of the neodermis which is a combination of blood vessels and connective tissue during wound healing. Fibroblasts are key cells in the wound healing process. TGF-β3 plays a critical role in scar-free wound healing and fibroblast actions in the wound healing process. The aim of this study was to express the TGF-β3 gene (tgf-b3) in human foreskin fibroblasts (HFF’s).

Methods:

We obtained HFF’s from a newborn and a primary fibroblast culture was prepared. The cells were transfected with TGF-β3-pCMV6-XL5 plasmid DNA by both lipofection and electroporation. Expression of TGF-β3 was measured by enzyme-linked immunosorbent assay (ELISA).

Results:

The highest TGF-β3 expression (8.3-fold greater than control) was obtained by lipofection after 72 hours using 3 µl of transfection reagent. Expression was 1.4-fold greater than control by electroporation.

Conclusions:

In this study, we successfully increased TGF-β3 expression in primary fibroblast cells. In the future, grafting these transfected fibroblasts onto wounds can help the healing process without scarring.Key Words: Fibroblasts, Gene expression, TGF-β3     

The computational study of the γ-Fe2O3 nanoparticle as Carmustine drug delivery system: DFT approach

In the present study, it is attempted to scrutinize the properties of the maghemite nanoparticle as a Carmustine drug delivery system by means of the density functional theory calculations regarding their geometries, adsorption energies, vibrational frequencies, and topological features of the electron density. Based on the density functional theory results, it is found that the interaction between Carmustine drug molecule and maghemite nanoparticle is weak; so that, the adsorption of the Carmustine drug is typically physisorption. It is also found that the intermolecular hydrogen bonds between the drug and the nanoparticle play the significant role in the stability of the physisorption configurations. The nature of the intermolecular interactions has been explored by calculation of the electron densities and their Laplacian at the bond critical points using Atoms-in-Molecule theory. Moreover, natural bond orbital analysis indicates that the Carmustine molecule can be adsorbed on the nanoparticle surface with a charge transfer from the Carmustine drug to the nanoparticle.     

Assessment of the Cannabinoid Content from Different Varieties of Cannabis sativa L. during the Growth Stages in Three Regions

Hemp (Cannabis sativa L.) belongs to the Cannabaceae family. It is very rich in chemical constituents, especially the cannabinoids which has not been reported in any other plant, and has broad pharmacological properties. Hemp as a multi-purpose crop is a good source of fibers, seed, fixed and volatile oil. It is known that the cannabinoid content of hemp is related to genetic factors, as well as plant's growth stages and environmental factors such as latitude, altitude, weather, particularly moisture availability and nutrient supply during the growing season. The present study was designed to produce hemp that contains allowable concentration of THC (<3 %) by comparing different varieties of hemp, different stages of plant growth, and different geographical locations where it was planted. To achieve this, seeds of two native populations from Iran (Fars and Yazd Provinces) and one foreign variety from France (Fedora17, as an industrial hemp cultivar) with its progenies (Fedora17-2) were cultivated in 3 research fields (Gilan, Golestan and Alborz provinces) in Iran. The following plant materials were extracted with methanol/chloroform and analyzed by HPLC: foliage in the vegetative stage, inflorescent in the flowering stage, inflorescent of seeds in the seeding stage and the mature seed. The THC concentration of Fedora17 (Fed17) in all three geographical locations was found to be under 0.03 % or even non-detectable. Same result was also observed in its progenies (Fed17-2), indicating stability of the trait in this cultivar. The THC concentration of the Yazd variety that was planted in Alborz and Gilan regions was less than 0.080 % in all growth stages. The female flowers planted in Golestan, showed a THC concentration of 1.029 % which was more than the allowed THC concentration of <3 %. The THC concentration in all growth stages of all of the different varieties planted varied from 0 to 1.392 %. The above results indicates that the type of cannabinoid produced depends on the difference in genetic prosperities of the different seed types as well as the growth stage in which the plant material was extracted. On the other hand, the climate and the region in which the seeds were planted had little influence on the THC concentration.