Sharif Digital Repository

To efficiently enhance the contrast obtaining from magnetic resonance imaging (MRI), pharmaceutical grade colloidal dispersions of PEG coated iron-based nanoparticles were prepared and compared to conventional pure iron oxide contrast agent. In this study, we synthesized ∼14 nm iron nanoparticles via NaBH4 reduction of iron(III) chloride in an aqueous medium. The resulting nanoparticles were further oxidized by two different methods via (CH3)3NO oxygen transferring agent and exposure to oxygen flow. XRD and electron microscopy analyses confirmed the formation of a second layer on the surface of α-Fe core. As magnetic measurements and Mössbauer spectra of 4-months post prepared nanoparticles... 

Investigating human brain activity during expressing emotional states provides deep insight into complex cognitive functions and neurological correlations inside the brain. To be able to resemble the brain function in the best manner, a complex and natural stimulus should be applied as well, the method used for data analysis should have fewer assumptions, simplifications, and parameter adjustment. In this study, we examined a functional magnetic resonance imaging dataset obtained during an emotional audio-movie stimulus associated with human life. We used Jackknife Correlation (JC) method to derive a representation of time-varying functional connectivity. We applied different binary measures... 

The main purpose of this study is to evaluate the effect of intravenous irradiation of different low-level laser wavelengths on the activity of lecithin-cholesterol acyltransferase (LCAT), paraoxonase (PON1), catalase, and ferric reducing ability of plasma (FRAP) in diabetic rats. First, diabetes was induced in rats using streptozotocin (STZ). Enzymes’ activity was measured in the blood samples and compared before and after intravenous laser blood irradiation. We used four continuous-wave lasers—IR (λ = 808 nm), Red (λ = 638 nm), Green (λ = 532 nm), and Blue (λ = 450 nm)—to compare the wavelength’s effect on different enzymes’ activity. Laser power was fixed at 0.01 mW and laser energy was... 

Herein, the graphene oxide (GO)/cobalt ferrite nanoparticles were used to apply the heat treatment on the breast cancer cell line of MCF7. The synthesized nanoparticles were evaluated before in vitro and in vivo studies, using transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), X-ray photoelectron spectroscopy (XPS), thermal property and relaxivity measurement. The nanoparticles showed a diameter of 5 nm with the ferrimagnetic property. Also, the nanoparticles were well distributed on the GO nanosheets. The related peaks of cobalt ferrite nanoparticles were approved by using XRD and XPS assays. During the in vitro investigations, IC50 with... 

Human infertility is a multifactorial disease that affects 8%–12% of reproductive-aged couples worldwide. However, the genetic causes of human infertility are still poorly understood. Synaptonemal complex (SC) is a conserved tripartite structure that holds homologous chromosomes together and plays an indispensable role in the meiotic progression. Here, we identified three homozygous mutations in the SC coding gene C14orf39/SIX6OS1 in infertile individuals from different ethnic populations by whole-exome sequencing (WES). These mutations include a frameshift mutation (c.204_205del [p.His68Glnfs∗2]) from a consanguineous Pakistani family with two males suffering from non-obstructive... 

Background: Accurate tracking of the heart surface motion is a major requirement for robot assisted beating heart surgery. Method: The feasibility of a stereo infrared tracking system for measuring the free beating heart motion was investigated by experiments on a heart motion simulator, as well as model surgery on a dog. Results: Simulator experiments revealed a high tracking accuracy (81 μm root mean square error) when the capturing times were synchronized and the tracker pointed at the target from a 100 cm distance. The animal experiment revealed the applicability of the infrared tracker with passive markers in practical heart surgery conditions. Conclusion: With the current technology,... 

In this study, physically cross-linked hydrogels were developed by freezing-thawing method while different concentrations of honey were included into the hydrogels for accelerated wound healing. The hydrogel was composed of chitosan, polyvinyl alcohol (PVA), and gelatin with the ratio of 2:1:1 (v/v), respectively. Further, the effect of honey concentrations on antibacterial properties, and cell behavior was investigated. In vivo studies, including wound healing mechanism using rat model and histological analysis of section tissue samples were performed. The results illustrated that the incorporation of honey in hydrogels increased the ultimate strain of hydrogels approximately two times,... 

This study presents a bilayer structure as a skin scaffold comprised of an electrospun sheet layer made of polycaprolactone and polyvinil alcohol and a porous hydrogel layer made of chitosan and gelatin. The hydrogel layer was fabricated by employing the freeze-gelation technique. The bilayer structure was achieved by pouring the hydrogel solution on the electrospun sheet at the bottom of a mold followed by the freeze-gelation technique to obtain a porous structure in the hydrogel. The hydrogel and hydrogel-electrospun samples were characterized by scanning electron microscopy, swelling, tensile strength, in vitro and in vivo analyses. From a mechanical strength standpoint, the combination... 

Background & Objective: The potent antioxidant property of fullerene C60 nanoparticles and their derivatives has been demonstrated in a wide range of in vitro and in vivo studies. Hence, we examined the effects of fullerene C60 on the oxidative stress parameters in brain and liver of the rats in normal situation. Materials & Methods: The study was performed in two groups of Wistar rats (each group, n = 6); normal and fullerene-treated normal animals. Treated rats received fullerene via oral gavage at dose of 1 mg/kg/day for 60 days. At termination of the study, the oxidative stress parameters were determined in brain and liver tissues, including the contents of glutathione (GSH) and... 

Context: Elevated expression of the folate receptor (FR) occurs in many human malignancies. Thus, folate targeting is widely utilized in drug delivery purposes specially using nano-radioactive agents. Aims: In this work, we report production and biological evaluation of gallium-67 labeled superparamagnetic iron oxide nanoparticles, embedded by folic acid (67 Ga-SPION-folate) complex especially in tumor-bearing mice for tumor imaging studies. Settings and Design: The structure of SPION-folate was confirmed by X-ray diffraction (XRD), transmission electron microscopy (TEM) and foureir transform infrared spectroscopy (FT-IR) analyses. The radiolabeled SPION-folate formation was confirmed by... 

Solid-phase microextraction probes based on poly(ethylene glycol)/C18-bonded silica were used for in vivo monitoring of drugs from circulating blood of beagles, over a period of 8 h. After sampling, the extracted drugs were subsequently quantified by liquid chromatography coupled with tandem mass spectrometry. External calibrations in whole blood and phosphate-buffered saline were used to correlate the amount of analytes extracted in regard to the total and free concentrations in blood respectively. The probe provided sufficient sensitivity for the drugs in the blood matrix, while the need for drawing blood was eliminated. The limit of detections of the method from whole blood were 1.7, 1.4... 

The oxidation-reduction (redox)–responsive micelle system is based on a diselenide-containing triblock copolymer, poly(ε-caprolactone)-bis(diselenide-methoxy poly(ethylene glycol)/poly(ethylene glycol)-folate) [PCL-(SeSe-mPEG/PEG-FA)2]. This has helped in the development of tumor-targeted delivery for hydrophobic anticancer drugs. The diselenide bond, as a redox-sensitive linkage, was designed in such a manner that it is located at the hydrophilic–hydrophobic hinge to allow complete collapse of the micelle and thus efficient drug release in redox environments. The amphiphilic block copolymers self-assembled into micelles at concentrations higher than the critical micelle concentration (CMC)... 

Aims Previous reports on the possible effects of Extremely Low Frequency Magnetic Fields (ELF MF) on mood have been paradoxical in different settings while no study has yet been conducted on animal behavior. In addition, it was shown that ELF MF exposure makes an increase in brain nitric oxide level. Therefore, in the current study, we aimed to assess the possible effect(s) of ELF MF exposure on mice Forced Swimming Test (FST) and evaluate the probable role of the increased level of nitric oxide in the observed behavior. Main methods Male adult mice NMRI were recruited to investigate the short term and long term ELF MF exposure (0.5 mT and 50 Hz, single 2 h and 2 weeks 2 h a day). Locomotor... 

Introduction: It has shown that listening to Mozart music can potentiate spatial tasks in human; and reduce seizure attacks in epileptic patients. A few studies have reported the effects of prenatal plus postpartum exposure of mice to the Mozart music on brain-drived neurotrophic factor (BDNF) in the hippocampus. Here we investigated the effect of postpartum exposure to The Mozart music on BDNF concentration in the hippocampus of rat. Methods: Thirty male one day old newborn Wistar rats divided randomly in two equal experimental and control groups. Experimental group exposed to slow rhythm Mozart music (Mozart Sonata for two pianos KV 448, 6 hour per day; sound pressure levels, between 80... 

Local three-stranded DNA/RNA hybrid regions of genomes (R-loops) have been detected either by binding of a monoclonal antibody (DRIP assay) or by enzymatic recognition by RNaseH. Such a structure has been postulated for mouse and human telomeres, clearly suggested by the identification of the complementary RNA Telomeric repeat-containing RNA “TERRA”. However, the tremendous disparity in the information obtained with antibody-based technology drove us to investigate a new strategy. Based on the observation that DNA/RNA hybrids in a triplex complex genome co-purify with the double-stranded chromosomal DNA fraction, we developed a direct preparative approach from total protein-free cellular... 

Purpose: Tests on animals of different species with large differences in intervertebral disc size are commonly used to investigate the therapeutic efficacy of intravenously injected solutes in the disc. We hypothesize that disc size markedly affects outcome. Methods: Here, using a small non-metabolized molecule, glucosamine (GL) as a model solute, we calculate the influence of disc size on transport of GL into rat, rabbit, dog and human discs for 10 h post intravenous-injection. We used transient finite element models and considered an identical GL supply for all animals. Results: Huge effects of disc size on GL concentration profiles were found. Post-injection GL concentration in the rat... 

Since physiological and pathological processes occur at nano-environments, nanotechnology has considered as an efficient tool for designing of next generation specific biomolecules with enhanced pharmacodynamic and pharmacodynamic properties. In the current investigation, by control of the size and hydrodynamic volume at the nanoscale, for the first time, physicochemical and pharmacokinetic properties of an anti-VEGFA nanobody was remarkably improved by attachment of a Proline-Alanine-Serine (PAS) rich sequence. The results elucidated unexpected impressive effects of PAS sequence on physicochemical properties especially on size, hydrodynamics radius, and even solubility of nanobody. CD... 

Background: Melittin, a peptide component of honey bee venom, is an appealing candidate for cancer therapy. In the current study, melittin, melittin-loaded niosome, and empty niosome had been optimized and the anticancer effect assessed in vitro on 4T1 and SKBR3 breast cell lines and in vivo on BALB/C inbred mice. "Thin-layer hydration method" was used for preparing the niosomes; different niosomal formulations of melittin were prepared and characterized in terms of morphology, size, polydispersity index, encapsulation efficiency, release kinetics, and stability. A niosome was formulated and loaded with melittin as a promising drug carrier system for chemotherapy of the breast cancer cells.... 

Background: Recent clinical studies of treating traumatic brain injury (TBI) with autologous adult stem cells led us to compare effect of intravenous injection of bone marrow mesenchymal stem cells (BMSC) and bone marrow hematopoietic stem cell mobilization, induced by granulocyte colony stimulating factor (G-CSF), in rats with a cortical compact device. Methods: Forty adult male Wistar rats were injured with controlled cortical impact device and divided randomly into four groups. The treatment groups were injected with 2 × 106 intravenous bone marrow stromal stem cell (n = 10) and also with subcutaneous G-CSF (n = 10) and sham-operation group (n = 10) received PBS and "bromodeoxyuridine...