Human chorionic gonadotropin attenuates amyloid-β plaques induced by streptozotocin in the rat brain by affecting cytochrome c-ir neuron density

Objective(s): Amyloid β plaques, in Alzheimer’s disease, are deposits in different areas of the brain such as prefrontal cortex, molecular layer of the cerebellum, and the hippocampal formation. Amyloid β aggregates lead to the release of cytochrome c and finally neuronal cell death in brain tissue. hCG has critical roles in brain development, neuron differentiation, and function. Therefore, we investigated the effect of hCG on the density of the congophilic Aβ plaque and cytochrome c-ir neurons in the hippocampus, prefrontal cortex, and cerebellum of Streptozotocin (STZ)-treated rats. Materials and Methods: Alzheimer model in rats (except the control group) was induced by streptozotocin (3 mg/kg, Intracerebroventricularly (ICV)). Experimental group rats received streptozotocin and then different doses of hCG (50, 100, and 200 IU, intraperitoneally) for 3 days. 48 hr after last drug injection and after histological processing, the brain sections were stained by congo red for congophilic amyloid β plaques and cytochrome c in the hippocampus, prefrontal cortex, and cerebellum were immunohistochemically stained. Results: Density of congophilic Aβ plaques and cytochrome c-immunoreactive neurons was significantly higher in ICV STZ treated rats than controls. Treatment with three doses of hCG significantly decreased the density of congophilic Aβ plaques and cytochrome c-immunoreactive neurons in the rat hippocampus, prefrontal cortex, and cerebellum in ICV STZ-treated rats (

Miscible gas injection into the reservoirs for increasing oil production

© 2020 Saint Petersburg 2020 - Geosciences: Converting Knowledge into Resources. All rights reserved. Gas injection into the oil reservoirs is one of the effective methods of increasing oil recovery. The gas injection into the reservoirs when it is fully or partially miscible with oil is a difficult physical process from the point of view of mathematical modelling. The simulation of miscible gas injection process by the simulator could give a recommendation about the amount of required gas, injection pressure and other technological parameters. In this work, an industrial software was used to simulate the miscible gas injection process for an Iranian oil reservoir. We determined the amount of gas injection, total oil and gas production and oil recovery factor in the various scenarios of gas recycling. The simulation results showed that the amount production gas was less than the injection gas. In addition, the total oil production and recovery factor was a function of the amount of miscible gas injection

Simulation investigation of hydraulic fracturing process in the oil reservoirs

© 2020 Saint Petersburg 2020 - Geosciences: Converting Knowledge into Resources. All rights reserved. Hydraulic fracturing is one of the most common methods of formation treatment for increasing the production rate, which can effectively enhance the productivity index. Simulation of hydraulic fracturing before the actual operation can help have the more effective treatment. In this work, the fracture width, which can be crated during hydraulic fracturing process, was simulated depending on the time. In addition, the required injection pressure for an optimum operation was determined at various injection rates. Furthermore, the effect of rock permeability and proppant mass on the productivity index and oil production rate was investigated. The simulation results showed that the optimum injection rate for hydraulic fracturing process is 4 L/s. At this rate, the maximum injection pressure was about 14.3 MPa. Moreover, the highest amount of productivity index was observed at lower values of rock permeability

A Detailed Molecular Dynamics Simulation and Experimental Investigation on the Interfacial Bonding Mechanism of an Epoxy Adhesive on Carbon Steel Sheets Decorated with a Novel Cerium–Lanthanum Nanofilm

The influences of steel surface treatment by a novel cerium–lanthanum (Ce-La) nanofilm on the adhesion mechanism of an epoxy adhesive were studied through experimental and modeling approaches. The surface morphology and microstructure of the film deposited were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). The surface free energy and work of adhesion values were evaluated through contact angle analysis. Also, the interfacial adhesion strength between the epoxy adhesive and steel surface, together with failure forms, were examined through pull-off test, under dry and wet conditions, and Fourier transform infrared (FT-IR) spectroscopy. The results obtained from experiments revealed that depositing a Ce-La nanofilm on the steel surface increased its roughness and surface free energy, and strengthened the epoxy coating adhesion. It was also observed that the epoxy adhesion on the Ce-La treated steel was stronger, compared to the Ce-treated surface. Furthermore, the adhesion extent and surface bonding mechanism of aminoamide-cross-linked epoxy resin were computationally modeled by applying atomistic molecular dynamics (MD) and electronic density functional theory (DFT) methods. The modeling results evidenced that epoxy resin adhered more strongly to the conversion layer (represented by CeO₂ and La₂O₃), compared to an untreated steel surface (i.e., pure and oxidized iron). The epoxy binding onto CeO₂(111), La₂O₃(001), Fe₂O₃(110), and Fe₃O₄(100) almost occurred via electrostatic interactions, while its adhesion mechanism over FeO(100) and Fe(110) surfaces was based on van der Waals forces. The computations also demonstrated that the epoxy adsorption energy decreased in wet environments, because of solvent affinity toward the epoxy and the surface, but the rate of reduction was smaller over CeO₂ and La₂O₃, compared to that observed with iron oxides. These modeling outcomes were consistent with our experiments and proposed the superior epoxy adhesion on modified steel sheets

Human chorionic gonadotropin decreases the phosphorylated tau protein level in streptozotocin-Alzheimeric male rats' hippocampus

Introduction: The pharmacological suppression of luteinising hormone or human chorionic gonadotropin (hCG) can reduce Aβ plaques in the brains of rats and mice, but the effects of hCG on the phosphorylated tau protein level in the hippocampus have not been studied. Therefore, we investigated the effects of hCG on the phosphorylated tau protein level and its effect on hCG receptor-immunoreactive neuron density in the hippocampus of Alzheimer's disease (AD) model rats (streptozotocin STZ injected intracerebroventricularly). Material and methods: The rats were administered hCG (50, 100, and 200 IU/200 µl saline, intraperitoneally) or vehicle once/day for three days after injection of STZ. The passive avoidance memory test was performed 6 hours after the last hCG injection. The phosphorylated tau protein level in the hippocampus was measured by ELISA, and hCG receptor-immunoreactive neurons were shown by immunohistochemical technique in areas of hippocampus. Results: Treatment with hCG attenuated memory deficiencies and reduced the level of phosphorylated tau protein in the hippocampus. hCG also improved the density of hCG receptor-immunoreactive neurons. The high dose of hCG hormone (200 IU/200 µl saline) seemed to have a significant effect on passive avoidance memory, phosphorylated tau protein concentration, and accumulation of hCG receptor-immunoreactive neurons in Alzheimeric rats' hippocampus. Conclusions: In conclusion, hCG can provide protection against memory deficits induced by STZ and it can inhibit accumulation of tau hyperphosphorylation in the hippocampus. Furthermore, hCG can increase the hCG receptor-ir neurons number in the rats hippocampus after ICV injection of STZ. © 2018 Termedia Publishing House Ltd. All Rights Reserved

Effects of hCG on reduced numbers of hCG receptors in the prefrontal cortex and cerebellum of rat models of Alzheimer�s disease

Age-associated changes in the levels of luteinizing hormone and human chorionic gonadotropin (hCG) are potential risk factors for Alzheimer�s disease (AD); hCG concentration is related to the incidence of AD. The highest density of hCG receptors is in zones of the brain that are vulnerable to AD and streptozotocin (STZ) can decrease the density of this receptor. We investigated the effects of different doses of hCG on hCG receptor density in the prefrontal cortex and cerebellum in a rat model of STZ-induced AD. AD was induced by intracerebroventricular injection of 3 mg/kg STZ. The resulting AD rats were treated for 3 days with 50, 100 or 200 IU/200 μl hCG, or with saline as a control. Sections of prefrontal cortex and cerebellum were stained immunohistochemically and hCG receptor-immunoreactive (ir) neurons were counted. STZ injected into the lateral ventricles of rat brains reduced the density of hCG receptor-ir neurons in the prefrontal cortex and cerebellum. hCG administration resulted in a significant dose-dependent increase in the number of hCG receptor-ir neurons in the prefrontal cortex and cerebellum. The maximum increase in the number of receptors occurred following the 200 IU dose of hCG. Administration of hCG ameliorated the lowered density of hCG receptor-ir neurons in the cerebellum and prefrontal cortex in STZ-induced AD rats. © 2019, © 2019 The Biological Stain Commission

Does the application of GaAlAs laser and platelet-rich plasma induce cell proliferation and increase alkaline phosphatase activity in human dental pulp stem cells?

Blood extracts containing platelet products are gaining popularity in promoting healing and pulp regeneration. This study was designed to evaluate the effect of platelet-rich plasma (PRP) and gallium�aluminum�arsenide (GaAlAs) laser on proliferation and differentiation of human dental pulp stem cells (hDPSCs). In this ex vivo study, hDPSCs isolated from impacted mandibular third molars were cultured in Dulbecco�s Modified Eagle�s medium )DMEM(with 10 fetal bovine serum (FBS). After reaching the desired confluence, the cells were distributed into 4 groups, namely, control, PRP, laser, and PRP+laser for MTT assay and alkaline phosphatase (ALP) test. In the PRP and PRP+laser groups, 10 PRP was added to each well on the plate. In the laser and PRP+laser groups, as for the proliferation test, laser irradiation was carried out for 45 s, while 135 s was designated for ALP test. After 1, 3, and 5 days, cell proliferation and ALP activity were assessed using MTT and ALP colorimetric assay, respectively. Two-way ANOVA was utilized to analyze data. In PRP and PRP+laser groups, cell proliferation and viability increased until day 3 but began to decline afterwards until the 5th day. In the laser group, the increase in proliferation and viability was observed till day 5 which was less than the control group. Laser and control groups exhibited significantly higher cell viability and proliferation than both PRP and PRP+laser groups. ALP activity was more pronounced in PRP+laser, PRP, and laser in descending order; however, all were less than that of the control group. Only in the control group did the ALP activity augment during the 5-day period. Laser irradiation could induce pulp cell proliferation and demonstrated a better performance than PRP in this regard. © 2021, The Author(s), under exclusive licence to Springer-Verlag London Ltd. part of Springer Nature

Photocatalytic, corrosion protection and adhesion properties of acrylic nanocomposite coating containing silane treated nano zinc oxide: A combined experimental and simulation study

The influence of silane treated nano zinc oxide (nZnO) on the protection, photocatalytic properties and interfacial interactions in acrylic/carbon steel systems was investigated. For this purpose, nZnO particles have been synthesized using microwave irradiation method. The morphology of synthesized zinc oxide nanoparticles was studied by scanning electron microscopy (SEM). The nZnO were treated by 3(2-amino ethyl amino) propyl trimethoxysilane. Fourier transforms infrared spectroscopy (FTIR) and thermogravimetry (TGA) techniques have been used to prove success of nZnO surface modification. In the next step, nanocomposites were prepared and coated on carbon steel by dip-coating method. Corrosion resistances of coatings were evaluated by electrochemical impedance spectroscopy (EIS). Field emission scanning electron microscopy (FE-SEM) has been carried out to study morphology of cross section of films. Moreover, to study the hydrophillicity and photocatalytic properties of coating surface, contact angle of the nanocomposites coating surface have been measured. Finally interfacial adhesion and their mechanisms have been studied by molecular dynamics (MD) and first principle quantum mechanics (QM) simulation method.Accepted Author Manuscript(OLD) MSE-