Sharif Digital Repository

A Zn-Rich (GaN)1−x(ZnO)xnanostructure was synthesized with the assistance of a high-gravity technique in order to reduce the reaction time and temperature. The synthesized inorganic nanomaterial has been applied in both drug and gene delivery systems, and as the first fully inorganic nanomaterial, it was investigated in a comprehensive cellular investigation as well. In order to increase the potential bioavailability, as well as the interactions with the pCRISPR, the nanomaterial was enriched with additional Zn ions. The nanomaterial and the final nanocarrier were characterized at each step before and after any biological analysisviaFESEM, AFM, TEM, FTIR and XRD. The polymer coated... 

Glioma is a common type of tumor that develops in the brain. Due to many differences in the shape and appearance, accurate segmentation of glioma for identifying all parts of the tumor and its surrounding tissues in cancer detection is a challenging task in cancer detection. In recent researches, the combination of atlas-based segmentation and machine learning methods have presented superior performance over other automatic brain MRI segmentation algorithms. To overcome the side effects of limited existing information on atlas-based segmentation, and the long training and the time consuming phase of learning methods, we proposed a semi-supervised learning framework by introducing a... 

Improving detection efficiency in small animal PET scanners without degrading spatial resolution is one of the main problems of these scanners. Commercial small animal PET scanners use different methods to achieve desirable levels of sensitivity and spatial resolution. GE Healthcare eXplore VISTA PET scanner uses double layer (LYSO-GSO) depth-of-interaction (DOI) capable cuboid detector modules. In this work, the design of GE Healthcare eXplore VISTA PET scanner is improved using tapered detector geometry instead of cuboid geometry. Using tapered detector geometry, the gaps between adjacent modules are filled and the sensitive volume has increased about 11.5%. The new designed PET scanner... 

Graphene oxide (GO) was chemically modified withpara-aminobenzoic acid (PABA) to immobilize copper(ii) ions on its surface and used as a nanocatalyst for the oxidative C(sp2)-H bond amination reaction. A practical method to prepare Cu2+supported onpara-aminobenzoic acid grafted on GO was reported. The prepared Cu2+@GO/PABA was characterized by FT-IR, XRD, SEM, AFM, TEM, UV-Vis, and ICP techniques. The results showed that the morphology, distribution, and loading of copper ions could be well-adjusted by grafting of PABA on GO. Moreover, just 2 mol% of Cu2+@GO-PABA could catalyze the C-H activation reaction of benzoxazole and benzothiazole with secondary amines in >94% yields. Also, the... 

Atherosclerosis as a common cardiovascular disease is a result of both adverse hemodynamics conditions and monocyte deposition within coronary arteries. It is known that the adhesion of monocytes on the arterial wall and their interaction with the vascular surface are one of the main parameters in the initiation and progression of atherosclerosis. In this work, hemodynamic parameters and monocyte deposition have been investigated in a 3D computational model of the Left Anterior Descending coronary artery (LAD) and its first diagonal branch (D1) under the heart motion. A one-way Lagrangian approach is performed to trace the monocyte particles under different blood flow regimes and heart motion... 

Targeted drug delivery using nanocarriers (NCs) is one of the novel techniques that has recently been used to improve drug delivery to the Abdominal aortic aneurysm (AAA) disease. The purpose of this study is to evaluate the surface density of NCs (SDNC) adhered via ligand-receptor binding to the inner wall of AAA. For this purpose, fluid–structure interaction (FSI) analysis was first performed for the patient-specific and ideal AAA models. Then, by injecting NCs into the aortic artery, the values of SDNC adhered to and interacted with AAA wall were obtained. Two types of NCs, liposomes, and solid particles in four different diameters, were used to investigate the effect of the diameter and... 

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... 

In this research, the efficiency of the integrated fixed-film activated sludge-oxic settling anoxic (IFAS-OSA) system in biological nutrient removal was studied. The oxic-settling anoxic (OSA) process is known as a cost effective way to reduce the nutrients (nitrogen and Phosphorus). According to the results, the percentages of total nitrogen removal efficiency in the IFAS, IFAS-OSA2h and IFAS-OSA4h systems were 78.56 ± 2.46, 83.60 ± 0.92 and 85.03 ± 1.69, respectively, while the percentages of phosphorus removal efficiency in these systems were 32.69 ± 8.25, 36.35 ± 6.73 and 39.87 ± 3.61, respectively. The PCR-RFLP method showed that C. albicans had the greatest prevalence (n = 36, 90%).... 

Stem cell treatment is promising in the various disorders treatment, but its effect is confined by the adverse conditions in the damaged tissues. The utilization of hydrogels has been suggested as a procedure to defeat this issue by developing the engraftment and survival of injected stem cells. Specifically, injectable hydrogels have drawn much attention due to their shape adaptability, ease of use, and the capability to reach body parts that are hard to access. In this study, the thermosensitive injectable hydrogels based on oxidized alginate, gelatin, and carbon nitride quantum dots (CNQDs) have been fabricated for tissue engineering. The mechanical characteristics of the nanocomposite... 

Mechanical ventilation (MV) can result in long-term brain impairments that are resistant to treatment. The mechanisms underlying MV-induced brain function impairment remain unclear. Since nasal airflow modulates brain activity, here we evaluated whether reinstating airflow during MV could influence the memory performance of rats after recovery. Rats were allocated into two study groups: one group received rhythmic air-puff into the nasal cavity during MV and a control group that underwent ventilation without air-puff. During MV, air-puffs induced time-locked event potentials in OB, mPFC and vHPC and significantly increased the oscillatory activity at the air-puff frequency. Furthermore, in... 

Recent studies have provided clues for participation of apoptosis related genes in the development of periodontitis. We examined expression of four apoptosome related genes namely CPSF7, AGO2, WDR33 and HUR1 in the blood and tissues of patients with stage III-IV periodontitis compared with control blood/tissue samples. Expression of AGO2 was significantly higher in the blood specimens of individual having periodontitis compared with healthy persons (ratio of mean expression = 6.9, P value = 4.79E−02). However, when categorizing individuals based on their gender, none of comparisons yielded significant results. Expression of AGO2 was not different between tissue samples of patients and... 

Irregular hemodynamics affects the progression of various vascular diseases, such atherosclerosis or aneurysms. Despite the extensive hemodynamics studies on animal models, the inter-species differences between humans and animals hamper the translation of such findings. Recent advances in vascular tissue engineering and the suitability ofin vitromodels for interim analysis have increased the use ofin vitrohuman vascular tissue models. Although the effect of flow on endothelial cell (EC) pathophysiology and EC-flow interactions have been vastly studied in two-dimensional systems, they cannot be used to understand the effect of other micro- and macro-environmental parameters associated with... 

Background: The exact pathogenic mechanism causes hair miniaturization during androgenic alopecia (AGA) has not been delineated. Recent evidence has shown a role for non-coding regulatory RNAs, such as microRNAs (miRNAs), in skin and hair disease. There is no reported information about the role of miRNAs in hair epithelial cells of AGA. Objectives: To investigate the roles of miRNAs affecting AGA in normal and patient's epithelial hair cells. Methods: Normal follicular stem and progenitor cells, as well as follicular patient's stem cells, were sorted from hair follicles, and a miRNA q-PCR profiling to compare the expression of 748 miRNA (miRs) in sorted cells were performed. Further, we... 

Melanoma is the deadliest type of human skin cancer. However, it is curable if diagnosed in an early stage. Recently, computer aided diagnosis (CAD) systems have drawn much interests. Segmentation is a crucial step of a CAD system. There are different types of skin lesions having high similarities in terms of color, shape, size and appearance. Most available works focus on a binary segmentation. Due to the huge variety of skin lesions and high similarities between different types of lesions, multi-class segmentation is still a challenging task. Here, we propose a method based on joint dictionary learning for multi-class segmentation of dermoscopic images. The key idea is based on combining... 

Adult cardiomyocytes are terminally differentiated cells that result in minimal intrinsic potential for the heart to self-regenerate. The introduction of novel approaches in cardiac tissue engineering aims to repair damages from cardiovascular diseases. Recently, conductive biomaterials such as carbon- and gold-based nanomaterials, conductive polymers, and ceramics that have outstanding electrical conductivity, acceptable mechanical properties, and promoted cell-cell signaling transduction have attracted attention for use in cardiac tissue engineering. Nevertheless, comprehensive classification of conductive biomaterials from the perspective of cardiac cell function is a subject for... 

Background: The Central Sensitization Inventory (CSI) is a patient-reported tool to assess symptoms associated with central sensitization (CS). It consists of two parts: Part A assesses 25 somatic and emotional CS-related health symptoms, and part B asks if one has previously been diagnosed with a list of 10 Central Sensitivity Syndromes and related conditions. Objectives: The aim of this study was to translate and cross-culturally adapt the CSI into Persian and to evaluate its psychometric properties. Design: Cross-sectional study. Method: After completing the Persian translation, the psychometric properties of the Persian CSI (CSI-Per) were evaluated in 256 patients with chronic pain and... 

The role of emulsions as a prevalent phenomenon is broadly investigated in the petroleum industry since forming the emulsion has many severe harmful implications. Heavy components of crude oil such as wax and asphaltene make the water-in-oil (w/o) emulsion more stable, while the role of these components on the emulsion viscosity has not been fully understood. In this regard, to find a proper demulsifier to break these emulsions, it is necessary to know the mechanisms of emulsion formation by heavy oil components. In this study, the effects of waxy-oil and asphaltenic-oil on w/o emulsion were investigated by measuring volume and viscosity of the formed emulsion after an elapsed time, followed... 

Currently, Alzheimer's disease (AD) accounts for more than half of all dementia cases. Although genetics, age, and environmental factors affect the disease, the cause of AD is not yet fully known. Various drugs have been proposed for the prevention and treatment of AD, but the delivery of these therapeutic agents to the brain is difficult. The blood–brain barrier prevents systemic drugs from accessing the central nervous system and designing a suitable system to overcome this barrier has attracted much attention. The intranasal pathway, given its proximity to the brain, provides a great opportunity for drug delivery. Understanding the physiological characteristics of the nose can be useful... 

This paper aims to propose a high-speed and accurate fully-automated method to detect COVID-19 from the patient's chest CT scan images. We introduce a new dataset that contains 48,260 CT scan images from 282 normal persons and 15,589 images from 95 patients with COVID-19 infections. At the first stage, this system runs our proposed image processing algorithm that analyzes the view of the lung to discard those CT images that inside the lung is not properly visible in them. This action helps to reduce the processing time and false detections. At the next stage, we introduce a novel architecture for improving the classification accuracy of convolutional networks on images containing small... 

In addition to its biological importance, DPhPC lipid bilayers are widely used in droplet bilayers, study of integral membrane proteins, drug delivery systems as well as patch-clamp electrophysiology of ion channels, yet their mechanical properties are not fully measured. Herein, we examined the effect of the ether linkage on the mechanical properties of ester- and ether-DPhPC lipid bilayers using all-atom molecular dynamics simulation. The values of area per lipid, thickness, intrinsic lateral pressure profile, order parameter, and elasticity moduli were estimated using various computational frameworks and were compared with available experimental values. Overall, a good agreement was...