ABSTRACT
BACKGROUND: The major challenge of tissue engineering is to develop constructions with suitable properties which would mimic the natural extracellular matrix to induce the proliferation and differentiation of cells. Poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) (PCL-PEG-PCL, PCEC), chitosan (CS), nano-silica (n-SiO₂) and nano-hydroxyapatite (n-HA) are biomaterials successfully applied for the preparation of 3D structures appropriate for tissue engineering. METHODS: We evaluated the effect of n-HA and n-SiO₂ incorporated PCEC-CS nanofibers on physical properties and osteogenic differentiation of human dental pulp stem cells (hDPSCs). Fourier transform infrared spectroscopy, field emission scanning electron microscope, transmission electron microscope, thermogravimetric analysis, contact angle and mechanical test were applied to evaluate the physicochemical properties of nanofibers. Cell adhesion and proliferation of hDPSCs and their osteoblastic differentiation on nanofibers were assessed using MTT assay, DAPI staining, alizarin red S staining, and QRT-PCR assay. RESULTS: All the samples demonstrated bead-less morphologies with an average diameter in the range of 190–260 nm. The mechanical test studies showed that scaffolds incorporated with n-HA had a higher tensile strength than ones incorporated with n-SiO₂. While the hydrophilicity of n-SiO₂ incorporated PCEC-CS nanofibers was higher than that of samples enriched with n-HA. Cell adhesion and proliferation studies showed that n-HA incorporated nanofibers were slightly superior to n-SiO₂ incorporated ones. Alizarin red S staining and QRT-PCR analysis confirmed the osteogenic differentiation of hDPSCs on PCEC-CS nanofibers incorporated with n-HA and n-SiO₂. CONCLUSION: Compared to other groups, PCEC-CS nanofibers incorporated with 15 wt% n-HA were able to support more cell adhesion and differentiation, thus are better candidates for bone tissue engineering applications.
Subject(s)
Humans , Biocompatible Materials , Bone and Bones , Cell Adhesion , Chitosan , Dental Pulp , Durapatite , Extracellular Matrix , Hydrophobic and Hydrophilic Interactions , Nanofibers , Nanoparticles , Osteoblasts , Silicon Dioxide , Spectroscopy, Fourier Transform Infrared , Stem Cells , Tensile Strength , Tissue EngineeringABSTRACT
Aim: The aim of the present study was to determine the prevalence and subtype distribution of Blastocystis and its relation with demographic data and symptoms in humans referred to medical centers in Ahvaz 2014-2015
Background: Infections with intestinal parasites are one of the most important threats to human health worldwide, especially in tropical and subtropical areas. Blastocystis sp. is a common parasite of humans with a vast variety of non-human hosts. We aimed to study the prevalence and subtypes of Blastocystis sp. in individuals referred to medical laboratories in Ahvaz city, southwest Iran
Methods: From September 2014 to September 2015, 618 stool samples were collected from 16 medical laboratories in Ahvaz, and examined using direct wet mount, formalin-ether concentration, a modified version of the Ziehl-Neelsen staining technique, and cultivation in xenic HSr + S medium. Subtypes of positive Blastocysts sp. were obtained using the "barcoding" method. The results were analyzed using SPSS software, version 16, with Chi-square and Fisher's exact test
Results: Totally, 325 [52.6%] of the referred individuals were men and 293 [47.4%] were women. Blastocystis sp. was observed in 146 [23.6%] samples. Co-infections with other intestinal parasites were found in 32 [5.17%] cases. Out of the 146 positive isolates, 20.83%, 20.83% and 58.34% belonged to ST1, ST2, ST3 respectively
Conclusion: Blastocystis sp. was quite common in the study population, with a carrier rate corresponding to nearly one in every four individuals. The subtype distribution identified in the present study was largely identical to that reported from other studies in Iran, with ST3 being the most common