Optimization and synthesis of a novel sorbent composite based on magnetic chitosan-amine-functionalized bimetallic MOF for the simultaneous dispersive solid-phase microextraction of four aflatoxins in real water, herbal distillate, and food samples.

Aflatoxins (AFs), an important category of pollutants, are formed in many foods and adversely affect human health. Therefore, their determination is critical to ensuring human food health. An efficient dispersive solid-phase microextraction technique was developed as a simple and straightforward sample preparation technique for determination of four aflatoxins using a high-performance liquid chromatography (HPLC) fluorescence detector. A novel efficient, green sorbent for extracting AFs was synthesized based on hydrothermal and chemical strategies. The amounts of three sorbent components were optimized using a mixture design (simplex lattice design), including 14 experiments. The optimal amount of amino-bimetallic Fe/Ni-MIL-53 nanospheres, chitosan, and magnetic Fe3O4 nanoparticles as sorbent components was 0.87, 0.67, and 0.47 g, respectively. Also, various factors affecting the process of AF determination were studied and optimized in two successive experimental designs, including the definitive screening design and the Box-Behnken design. Under optimal conditions, the linear ranges for measuring aflatoxin B1, aflatoxin B2, aflatoxin G1, and aflatoxin G2 were 0.05-82.6, 0.07-86.4, 0.08-85.7, and 0.07-89.5 ng mL-1, respectively. The relative standard deviations under inter-day and intra-day conditions for measuring AFs at three analyte concentrations were determined in triplicate analysis and were in the ranges of 3.7-4.6% and 4.9-6.1% for water sample analysis, respectively. The qualitative detection limits for determining AFs were between 0.01 and 0.05 ng mL-1. The pre-concentration factor of the method for measuring AFs ranged from 739.7 to 802.1. The proposed method was used for determining AFs in several real samples, including herbal distillate, black tea, corn, and real water samples. The relative recovery and standard deviation were 87.8-97.8% and 4.10-6.82%, respectively.

vCOMBAT: a novel tool to create and visualize a computational model of bacterial antibiotic target-binding.

BACKGROUND: As antibiotic resistance creates a significant global health threat, we need not only to accelerate the development of novel antibiotics but also to develop better treatment strategies using existing drugs to improve their efficacy and prevent the selection of further resistance. We require new tools to rationally design dosing regimens from data collected in early phases of antibiotic and dosing development. Mathematical models such as mechanistic pharmacodynamic drug-target binding explain mechanistic details of how the given drug concentration affects its targeted bacteria. However, there are no available tools in the literature that allow non-quantitative scientists to develop computational models to simulate antibiotic-target binding and its effects on bacteria. RESULTS: In this work, we have devised an extension of a mechanistic binding-kinetic model to incorporate clinical drug concentration data. Based on the extended model, we develop a novel and interactive web-based tool that allows non-quantitative scientists to create and visualize their own computational models of bacterial antibiotic target-binding based on their considered drugs and bacteria. We also demonstrate how Rifampicin affects bacterial populations of Tuberculosis bacteria using our vCOMBAT tool. CONCLUSIONS: The vCOMBAT online tool is publicly available at https://combat-bacteria.org/ .

Ultrasonic assisted magnetic dispersive solid phase microextraction for pre concentration of serotonin-norepinephrine reuptake inhibitor drugs.

A simple and sensitive ultrasonic assisted magnetic dispersive solid phase microextraction method (UAMDSPME) coupled with high performance liquid chromatography was developed to determine serotonin-norepinephrine reuptake inhibitor drugs including duloxetine (DUL), venlafaxine (VEN) and atomoxetine (ATO) in human urine, river water and well water samples. A novel and efficient SPME sorbent, magnetic p-Phenylenediamine functionalized reduced graphene oxide Quantum Dots@ Ni nanocomposites (MrGOQDs-PD@ Ni), was prepared and applied for extraction of the analytes. Several effective parameters on the extraction efficiency of the analytes were investigated and optimized with experimental design approach. The performance of MrGOQDs-PD@ Ni as the SPME sorbent for the extraction of DUL, VEN and ATO was then compared with magnetic graphene oxide (MGO@Fe3O4) and magnetic reduced graphene oxide (MrGO@ Ni). Under the optimized conditions for the MrGOQDs-PD@ Ni sorbent, the intra-day relative standard deviations (RSDs, n = 5) and the limits of detections (LODs) were lower than 4.6% and 1.1 ngmL-1, respectively. Moreover, the good linear ranges were observed in wide concentration ranges with R-squared larger than 0.9878. Finally, the enrichment factors in the range of 137-183 and the recovery percentage in the range of 89.2-94.8% were obtained to determine the analytes in the real samples.

Disclination elastica model of loop collision and growth in confined nematic liquid crystals.

Theory and modeling are used to characterize disclination loop-loop interactions in nematic liquid crystals under capillary confinement with strong homeotropic anchoring. This defect process arises when a mesogen in the isotropic phase is quenched into the stable nematic state. The texture evolution starts with +1/2 disclination loops that merge into a single loop through a process that involves collision, pinching and relaxation. The process is characterized with a combined Rouse-Frank model that incorporates the tension and bending elasticity of disclinations and the rotational viscosity of nematics. The Frank model of disclinations follows the Euler elastica model, whose non-periodic solution, known as Poleni's curve, is shown to locally describe the loop-loop collision and to shed light on why loop-loop merging results in a disclination intersection angle of approximately 60°. Additional Poleni invariants demonstrate how tension and bending pinch the two loops into a single +1/2 disclination ring. The Rouse model of disclination relaxation yields a Cahn-Hilliard equation whose time constant combines the confinement, tension/bending stiffness ratio and disclination diffusivity. Based on predictions made using this three stage process, a practical procedure is proposed to find viscoelastic parameters from defect geometry and defect dynamics. These findings contribute to the evolving understanding of textural transformations in nematic liquid crystals under confinement using the disclination elastica methodology.

Mechanisms and shape predictions of nematic disclination branching under conical confinement.

Liquid crystals (LCs) are self-organizing anisotropic viscoelastic soft materials that flow like viscous liquids and display anisotropies like crystals. When a nematic liquid crystal is confined to a capillary tube with strong anchoring conditions, disclination defects of higher (+1) and lower (+1/2) topological charges can coexist, connected through a defect branch point. The shape of the +1/2 disclination lines emanating from the branch point are functions of confinement and bulk elasticity. Previous work shows that nematic liquid crystals under cylindrical confinement display a radial (one +1 line)-to-planar polar (two +1/2 lines) defect texture transition through the nucleation and uniform motion of a disclination branch point. Here we present analysis, scaling and modeling based on a non-linear non-local nematic elastic equation that shows that a branch point also can be generated from disclinations in a liquid crystal confined to different conical geometries with homeotropic anchoring conditions. The cone aperture increases the bending stiffness but decreases the curvature of the disclination. These competing effects lead to a decrease in the total disclination curvature, increase in elastic energy and volume of the branching region. The results are summarized into power laws and integrated into a shape/energy diagram that reveals the effects of confinement and its gradient (cone angle) on disclination shape selection. These new findings are useful to assess the Frank elasticity of new nematic liquid crystals and to predict novel defect structures in complex confinement, including biological microfluidics and mesophase fiber spinning.

Investigation of Signals and Transcription Factors for The Generation of Female Germ-Like Cells.

Objective: Primordial germ cell (PGCs) lines are a source of a highly specialized type of cells, characteristically oocytes,
during female germline development in vivo. The oocyte growth begins in the transition from the primary follicle. It is
associated with dynamic changes in gene expression, but the gene-regulating signals and transcription factors that control oocyte growth remain unknown. We aim to investigate the differentiation potential of mouse bone marrow mesenchymal stem cells (mMSCs) into female germ-like cells by testing several signals and transcription factors.
Materials and Methods: In this experimental study, mMSCs were extracted from mice femur bone using the flushing
technique. The cluster-differentiation (CD) of superficial mesenchymal markers was determined with flow cytometric analysis. We applied a set of transcription factors including retinoic acid (RA), titanium nanotubes (TNTs), and fibrin such as TNT-coated fibrin (F+TNT) formation and (RA+F+TNT) induction, and investigated the changes in gene, MVH/ DDX4, expression and functional screening using an in vitro mouse oocyte development condition. Germ cell markers expression, (MVH / DDX4), was analyzed with Immunocytochemistry staining, quantitative transcription-polymerase chain reaction (RT-qPCR) analysis, and Western blots.
Results: The expression of CD was confirmed by flow cytometry. The phase determination of the TNTs and F+TNT were confirmed using x-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. Remarkably, applying these transcription factors quickly induced pluripotent stem cells into oocyte-like cells that were sufficient to generate female germlike cells, growth, and maturation from mMSCs differentiation. These transcription factors formed oocyte-like cells specification of stem cells, epigenetic reprogramming, or meiosis and indicate that oocyte meiosis initiation and oocyte growth are not separable from the previous epigenetic reprogramming in stem cells in vitro.
Conclusion: Results suggested several transcription factors may apply for arranging oocyte-like cell growth and supplies an alternative source of in vitro maturation (IVM).

Silymarin Administration Attenuates Cirrhotic-induced Cardiac Abnormality in the Rats: A Possible Role of ß1-adrenergic Receptors and L-type Voltage-Dependent Calcium Channels.

Background: Cirrhotic cardiomyopathy is a well-recognized cardiac dysfunction in cirrhotic patients. Studies have confirmed the protective effects of silymarin in different types of cardiac injury. This study aimed to examine the effectiveness and molecular mechanism of silymarin against myocardial dysfunction and hypertrophy in a rat model of cirrhosis. Methods: The experiment was performed at Alborz University of Medical Sciences (Karaj, Iran) during 2020-2021. Thirty-two male Wistar rats were randomly divided into four groups of Sham-operated (control group for surgical procedures), Bile Duct Ligated (BDL), and two Silymarin extract (SE)-treated groups of 300 and 600 mg/Kg/day. After 28 days, serum levels of AST, ALT, GGT, and ALP, liver histopathological status, as well as cardiac mechanical function, were assessed. Cardiac ß1-adrenergic receptors (ß1-AR), L-type voltage-dependent calcium channels (L-VDCC), and GATA4 mRNA expression were also determined using real-time RT-PCR. Data analysis was performed using the one-way ANOVA followed by Duncan's multiple range test. Histological data has been analyzed with Kruskal-Wallis nonparametric test. The analysis was performed at P≤0.05. Results: BDL was associated with a significant elevation in serum AST, ALT, GGT, and ALP, development of necrosis and fibrosis of the liver texture, increased Heart Weight and Heart Weight to Body Weight ratio, enhanced cardiac mechanical function as well as a significant up-regulation of ventricular ß1-AR and L-VDCC. Administration of SE600, but not SE300, significantly reduced the serum levels of the enzymes and alleviated signs of liver necrosis and fibrosis. Cirrhotic-induced cardiac dysfunction was also restored by SE600, but not by the lower dose. In addition, cardiac expression of the ß1-AR and L-VDCC was down-regulated toward normal values by either higher or lower doses of the SE. Conclusion: Silymarin treatment in higher dose attenuated cirrhosis-associated cardiac remodeling and reduced cardiac mechanical dysfunctions.

Facial nerve regeneration using silicone conduits filled with ammonia-functionalized graphene oxide and frankincense-embedded hydrogel.

BACKGROUND: Silicone tube (ST) conduits have been accepted as a therapeutic alternative to direct nerve suturing in the treatment of nerve injuries; however, the search for optimal adjuncts to maximize the outcomes is still ongoing. Frankincense (Fr) and graphene oxide (GO) have both been cited as neuroregenerative compounds in the literature. This study assesses the efficacy of these materials using a ST conduit in a rat facial nerve motor neuron axotomy model, distal to the stylomastoid foramen. METHODS: Ammonia-functionalized graphene oxide (NH2-GO) and/or Fr extract were embedded in a collagen-chitosan hydrogel and were injected inside a ST. The ST was inserted in the gap between the axotomized nerve stumps. Return of function in eye closure, blinking reflex, and vibrissae movements were assessed and compared to control groups through 30 days following axotomy. To assess the histological properties of regenerated nerves, biopsies were harvested distal to the axotomy site and were visualized through light and fluorescence microscopy using LFB and anti-MBP marker, respectively. RESULTS: There was no significant difference in behavioral test results between groups. Histological analysis of the nerve sections revealed increased number of regenerating axons and mean axon diameter in NH2-GO group and decreased myelin surface area in Fr group. Using both NH2-GO and Fr resulted in increased number of regenerated axons and myelin thickness compared to the hydrogel group. CONCLUSIONS: The findings suggest a synergistic effect of the substances above in axon regrowth, notably in myelin regeneration, where Fr supposedly decreases myelin synthesis.

Simultaneous determination of organophosphorus pesticides residues in vegetable, fruit juice, and milk samples with magnetic dispersive micro solid-phase extraction and chromatographic method; recruitment of simplex lattice mixture design for optimization of novel sorbent composites.

Dispersive micro solid-phase extraction procedure using a novel and selective sorbent prepared from four components was developed as a sample preparation strategy for extracting five organophosphorus pesticides, including fenitrothion, malathion, ethion, and chlorpyrifos, and diazinon in several vegetables, fruit juices, and cow's milk samples. Due to the high importance of the sorbent in the microextraction process, the percentages of sorbent components, including metal-organic framework (ZIF-67), chitosan, magnetic Fe3O4 nanoparticles, and silica nanoparticles, were optimized by a simplex lattice mixture design. After optimizing the sorbent composite, effective parameters on the extraction of organophosphorus pesticides were optimized using a definitive screening design and Box-Behnken design, respectively. A surfactant (Triton X100) as a dispersion agent with a low volume (10 µL) was utilized in the microextraction procedure to reduce the sorbent dispersion time and increase the sorbent dispersion efficiency. Under the optimal conditions, linearity for the determination of fenitrothion, malathion, ethion, chlorpyrifos, and diazinon was in the concentration ranges of 0.13-1100, 0.27-1000, 0.38-1000, 0.21-1200, and 0.11-1100 ng mL-1 with a determination coefficient higher than 0.9906, respectively. The quantitation limits, detection limits, and relative standard deviations (n = 5) were lower than 0.38 ng mL-1, 0.11 ng mL-1, and 4.59% for the determination of organophosphorus pesticides. The method application for measuring OPPs on cucumber, carrot, tomato, apple juice, orange juice, and cow's milk indicated the presence of residual amounts of malathion in a cucumber sample, diazinon in a carrot sample, and chlorpyrifos in a tomato sample.

Yes-associated protein-1 may serve as a diagnostic marker and therapeutic target for residual/recurrent hepatocellular carcinoma post-transarterial chemoembolization☆.

BACKGROUND AND AIM: The transcriptional co-activator Yes-associated protein-1 (YAP1) has been implicated as an oncogene and is overexpressed in different kinds of human cancers, especially hepatocellular carcinoma (HCC). However, the role of YAP1 has not been reported in residual/recurrent HCC after transarterial chemoembolization (TACE). Our aim is to determine whether YAP1 is overexpressed in the residual/recurrent HCC after TACE. METHODS: A total of 105 tumor tissues from 71 patients including 30 cases of primary HCC without prior treatment, 35 cases of residual/recurrent HCC post TACE, and 6 cases of hepatoblastoma were included in the immunohistochemical study. YAP1 immunoreactivity was blindly scored as 0, 1+, 2+ or 3+ in density and percentages of positive cells. RESULTS: About 33.3% (10/30) of primary HCC without prior treatment showed 2+ of YAP1 immunoreactivity. While 82.8% (29/35) of residual/recurrent HCCs after TACE treatment displayed 2-3+ of YAP1 immunoreactivity, which was significantly higher compared to primary HCC without prior treatment (P = 0.0002). YAP1 immunoreactivity was moderately to strongly positive (2-3+) in 100% of the hepatoblastoma, particularly in the embryonal components (3+ in 100% cases). CONCLUSIONS: YAP1 is significantly upregulated in the residual/recurrent HCCs post TACE treatment, suggesting that YAP1 may serve as a sensitive diagnostic marker and a treatment target for residual/recurrent HCC post TACE.

Fabrication and characterisation of super-paramagnetic responsive PLGA-gelatine-magnetite scaffolds with the unidirectional porous structure: a physicochemical, mechanical, and in vitro evaluation.

Architecture and composition of Scaffolds are influential factors in the regeneration of defects. Herein, synthesised iron oxide (magnetite) nanoparticles (MNPs) by co-precipitation technique were evenly distributed in polylactic-co-glycolic acid (PLGA)-gelatine Scaffolds. Hybrid structures were fabricated by freeze-casting method to the creation of a matrix with tunable pores. The synthesised MNPs were characterised by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy, and vibrating sample magnetometer analysis. Scanning electron microscopy micrographs of porous Scaffolds confirmed the formation of unidirectional microstructure, so that pore size measurement indicated the orientation of pores in the direction of solvent solidification. The addition of MNPs to the PLGA-gelatine Scaffolds had no particular effect on the morphology of the pores, but reduced slightly pore size distribution. The MNPs contained constructs demonstrated increased mechanical strength, but a reduced absorption capacity and biodegradation ratio. Stability of the MNPs and lack of iron release was the point of strength in this investigation and were determined by atomic absorption spectroscopy. The evolution of rat bone marrow mesenchymal stem cells performance on the hybrid structure under a static magnetic field indicated the potential of super-paramagnetic constructs for further pre-clinical and clinical studies in the field of neural regeneration.

Magnetic ethylene diamine-functionalized graphene oxide as novel sorbent for removal of lead and cadmium ions from wastewater samples.

In this paper, magnetic ethylene diamine-functionalized graphene oxide (MDFGO) as a novel sorbent was synthesized and applied for removal of Pb(II) and Cd(II) from real wastewater samples. The morphology and molecular structure of MDFGO were studied by different analytical methods. The effective parameters in adsorption efficiency of Pb(II) and Cd(II) were studied and optimized using experimental design. Under the optimal condition, the effective parameters including pH, sorbent dosage, shaking rate, and adsorption time were 6.2, 33.0 mg, 500 rpm, and 11 min, respectively. Mechanism of adsorption kinetic was investigated using the Lagergren pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. It was found that adsorption of lead and cadmium ions in the MDFGO sorbent followed from pseudo-first-order and pseudo-second-order models, respectively. Thermodynamic parameters (ΔG°, ΔH°, and ΔS°) for the lead and cadmium ions uptake onto the MDFGO sorbent were calculated and indicated that the adsorption processes were spontaneous and endothermic in nature for both cations. In order to investigate the isotherm model for adsorption of Pb(II) and Cd(II), the experimental data were studied using the Langmuir, Freundlich, and Harkins-Jura isotherm models. The results fitted well with Freundlich model for both metal ions. The new sorbent (MDFGO) was applied to remove Pb(II) and Cd(II) from battery wastewater and electroplating wastewater. The removal percentage of Pb(II) and Cd(II) were 99.6±0.5 and 99.4±0.6, respectively, and demonstrated that the new sorbent was very suitable for removal of lead and cadmium ion from the real wastewater samples.

Outcomes for Umbilical Cord Blood Transplantation in Severe Combined Immunodeficiency Disorders: Ten-Year Experience.

The treatment of severe combined immunodeficiency (SCID) is immune reconstitution using hematopoietic stem cell (HSC) transplantation early in life. HLA-identical related donors are the preferred source of HSCs. Since sibling donors are available in <30% of patients, other sources of HSCs are considered-mismatched related donor, umbilical cord blood (UCB), and matched unrelated donor bone marrow. We report the outcome of 10 patients with SCID or combined immunodeficiency (CID) 10 years after UCB transplantation (UCBT) at our institution using a retrospective chart review. Eight patients were alive 10 years post-transplantation. This was the second transplant for 2 patients due to initial transplant engraftment failure. Immunologic reconstitution was demonstrated after transplant with presence of memory T cells at 3 months, naive T cells at 12 months, B cells at 3 months, and normal tetanus/diphtheria toxoid antibody responses at 2 years. Immune response remained robust 10 years post-transplantation. Eight patients developed stage I acute graft-versus-host disease (GvHD), 2 patients developed grades 2-4 GvHD, and 1 child developed chronic GvHD with bronchiolitis obliterans. UCB should be considered as an alternative HSC source for patients with SCID and CID because of its robust and sustained recovery of immune function, low risk of severe GvHD, and accessibility.

Comparison of Human Amniotic, Chorionic, and Umbilical Cord Multipotent Mesenchymal Stem Cells Regarding Their Capacity for Differentiation Toward Female Germ Cells.

Placenta harbors a plentiful source of various cells with stem cells or stem-like cell properties, which can be used in therapeutic procedures and research. Mesenchymal stem cells (MSCs) have attracted much attention due to their specific differentiation potential and tolerogenic properties. MSCs have been isolated from different parts of placenta; however, in this study, we isolated MSCs from amnion and chorion membrane, as well as umbilical cord (Wharton's jelly [WJ]) and compared their capacity regarding differentiation toward female germ cells under influence of 10 ng/mL BMP4. All placenta samples were collected from delivering mothers by normal cesarean section and cells were isolated by different methods. Results showed that all isolated cells were mostly positive for the MSC markers CD73, CD166, and CD105, and minimally reacted with CD34 and CD45 (hematopoietic markers). After differentiation induction using third passage cultured cells, immunocytochemistry staining showed that cells were positive for germline cell-related genes Ssea4, Oct4, and Ddx4, and oocyte-related gene Gdf9. RT-qPCR results indicated that human chorion MSCs (hCMSCs) had a greater potential to be differentiated into female germline cells. Moreover, the results of this study indicate that human umbilical cord MSCs originated from either male or female umbilical cord have the same differentiation potential into female germline cells. We recommend that for presumptive application of MSCs for infertility treatment and research, hUMSCs are best candidates due to their higher differentiation potential, ease of proliferation and expansion, and low immunogenicity.

Focal Injection of Ethidium Bromide as a Simple Model to Study Cognitive Deficit and Its Improvement.

INTRODUCTION: Memory and cognitive impairments are some of devastating outcomes of Multiple Sclerosis (MS) plaques in hippocampus, the gray matter part of the brain. The present study aimed to evaluate the intrahippocampal injection of Ethidium Bromide (EB) as a simple and focal model to assess cognition and gray matter demyelination. METHODS: Thirty Wistar rats were divided into three groups: control group, which received saline, as solvent of EB, into the hippocampus; and two experimental groups, which received 3 µL of EB into the hippocampus, and then, were evaluated 7 and 28 days after EB injection (n=10 in each group), using a 5-day protocol of Morris Water Maze (MWM) task as well as Transmission Electron Microscopy (TEM) assay. RESULTS: Seven days after EB injection, the behavioral study revealed a significance increase in travelled distance for platform finding in the experimental group compared to the control group. In addition, the nucleus of oligodendrocyte showed the typical clumped chromatin, probably attributed to apoptosis, and the myelin sheaths of some axons were unwrapped and disintegrated. Twenty-eight days after EB injection, the traveled distance and the time spent in target quadrant significantly decreased and increased, respectively in experimental groups compared to the control group. Also, TEM micrographs revealed a thin layer of remyelination around the axons in 28 days lesion group. DISCUSSION: While intracerebral or intraventricular injection of EB is disseminated in different parts of the brain and can affect the other motor and sensory systems, this model is confined locally and facilitates behavioral study. Also, this project could show improvement of memory function subsequent to the physiological repair of the gray matter of the hippocampus.

Theoretical predictions of disclination loop growth for nematic liquid crystals under capillary confinement.

The combination of low elasticity modulus, anisotropy, and responsiveness to external fields drives the rich variety of experimentally observed pattern formation in nematic liquid crystals under capillary confinement. External fields of interest in technology and fundamental physics are flow fields, electromagnetic fields, and surface fields due to confinement. In this paper we present theoretical and simulation studies of the pattern formation of nematic liquid crystal disclination loops under capillary confinement including branching processes from a m=+1 disclination line to two m=+1/2 disclination curves that describe the postnucleation and growth regime of the textural transformation from radial to planar polar textures. The early postnucleation and growth of emerging disclination loops in cylindrical capillaries are characterized using analytical and computational methods based on the nematic elastica that takes into account line tension and line bending stiffness. Using subdiffusive growth and constant loop anisotropy, we found that the solution to the nematic elastica is a cusped elliptical geometry characterized by exponential curvature variations. The scaling laws that govern the loop growth reflect the tension to bending elasticity balance and reveal that the loop dilation rate depends on the curvature and normal velocity of the disclination. The line energy growth is accommodated by the decrease in branch-point curvature. These findings contribute to the evolving understanding of textural transformations in nematic liquid crystals under confinement using the nematic elastic methodology.