A doxycycline-loaded microfiber of poly-metformin/PCL for eradicating melanoma stem cells.

Nowadays, electrospun fibrous mats are used as drug delivery systems for loading of potential drugs in order to kill cancer cells. In the study, a skin patch for treating melanoma cancer after surgery was made using polycaprolactone and polymetformin microfibers that were loaded with doxycycline (PolyMet/PCL@DOX), an anti-cancer stem cell agent. The morphology, structure, mechanical characteristics, swelling, and porosity of the electrospun microfibers were examined. Drug release andanticancereffectiveness of PolyMet/PCL@DOXwas evaluated against A375 melanoma cancer stem cells using the MTS, Flow cytometry, colony formation and CD44 expression assays. Scanning electron microscopy (SEM) verified the micro fibrous structure with a diameter of about 2.31 µm. The porosity and swelling percentages for microfibers was 73.5 % and 2.9 %, respectively. The tensile strength at the breaking point was equal to 3.84 MPa. The IC50 of PolyMet/PCL@DOX was 7.4 µg/mL. The survival rate of A375 cells after 72 h of PolyMet/PCL@DOX treatment was 43.9 %. The colony formation capacity of A375 cells decreased after PolyMet/PCL@DOX treatment. The level of CD44 expression in the PolyMet/PCL@DOX group decreased compared to the control group. Generally, PolyMet/PCL@DOX microfibers can be a promising candidate as a patch after surgery to eradicate cancer stem cells, effectively.

Levofloxacin loaded poly (ethylene oxide)-chitosan/quercetin loaded poly (D,L-lactide-co-glycolide) core-shell electrospun nanofibers for burn wound healing.

This study developed a new burn wound dressing based on core-shell nanofibers that co-deliver antibiotic and antioxidant drugs. For this purpose, poly(ethylene oxide) (PEO)-chitosan (CS)/poly(D,L-lactide-co-glycolide) (PLGA) core-shell nanofibers were fabricated through co-axial electrospinning technique. Antibiotic levofloxacin (LEV) and antioxidant quercetin (QS) were incorporated into the core and shell parts of PEO-CS/PLGA nanofibers, respectively. The drugs could bond to the polymer chains through hydrogen bonding, leading to their steady release for 168 h. An in vitro drug release study showed a burst effect followed by sustained release of LEV and QS from the nanofibers due to the Fickian diffusion. The NIH 3T3 fibroblast cell viability of the drug loaded core-shell nanofibers was comparable to that in the control (tissue culture polystyrene) implying biocompatibility of the nanofibers and their cell supportive role. However, there was no significant difference in cell viability between the drug loaded and drug free core-shell nanofibers. According to in vivo experiments, PEO-CS-LEV/PLGA-QS core-shell nanofibers could accelerate the healing process of a burn wound compared to a sterile gauze. Thanks to the synergistic therapeutic effect of LEV and QS, a significantly higher wound closure rate was recorded for the drug loaded core-shell nanofibrous dressing than the drug free nanofibers and control. Conclusively, PEO-CS-LEV/PLGA-QS core-shell nanofibers were shown to be a promising wound healing material that could drive the healing cascade through local co-delivery of LEV and QS to burn wounds.

Evaluating the therapeutic effects of isotretinoin on patients with coronavirus disease 2019 (COVID-19): A controlled open-label clinical trial.

Coronavirus disease 2019 (COVID-19) is still a global health issue with no certain treatment option. So far, various treatments have been suggested among which one can mention isotretinoin. The aim of the present study was to investigate the potential of this medication as a side treatment for COVID-19. This open-label controlled clinical trial with the approval ID of IRCT20190624043993N3 was conducted in Farabi Hospital, Kermanshah University of Medical Sciences, Kermanshah, Iran. Considering the inclusion and exclusion criteria, 52 patients diagnosed with COVID-19 were enrolled. The control group only received standard of care (SOC) treatment while the intervention arm received 40 mg per day of isotretinoin along with the SOC. The patients were followed until discharge. The results showed no death among the groups. The hospitalization duration in the intervention and SOC groups were 5.1 ± 2.29 and 5.1 ± 3.44 days, respectively with no statistical difference (P = 0.98). Moreover, the SpO2, pulse rate, respiratory rate, and blood pressure also showed no statistical difference neither at admission nor upon discharge (P > 0.05). The laboratory investigations showed that white blood cells, absolute lymphocyte count, hemoglobin value, and platelet count did not differ between the groups at admission or upon discharge (P > 0.05). According to the results, it seems that isotretinoin didn't act as a potent side therapy in patients with COVID-19. However, due to the small sample size, we suggest further investigations.

Fabrication of a Controlled-Release Core-Shell Floating Tablet of Ketamine Hydrochloride Using a 3D Printing Technique for Management of Refractory Depressions and Chronic Pain.

In this study, a novel floating, controlled-release and core-shell oral tablet of ketamine hydrochloride (HCl) was produced using a dual extrusion by 3D printing method. A mixture of Soluplus® and Eudragit® RS-PO was extruded by a hot-melt extrusion (HME) nozzle at 150-160 °C to fabricate the tablet shell, while a second nozzle known as a pressure-assisted syringe (PAS) extruded the etamine HCl in carboxymethyl cellulose gel at room temperature (25 °C) inside the shell. The resulting tablets were optimized based on the United States pharmacopeia standards (USP) for solid dosage forms. Moreover, the tablet was characterized using Fourier-transform infrared (FTIR) spectrum, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and buoyancy techniques. The results showed a desired dissolution profile for a 100% infill optimized tablet with total drug release (100%) during 12 h. Weight variation and content uniformity of the tablets achieved the USP requirements. SEM micrographs showed a smooth surface with acceptable layer diameters. According to the FTIR analysis, no interference was detected among peaks. Based on DSC analysis, the crystallinity of ketamine HCl did not change during melt extrusion. In conclusion, the floating controlled-release 3D-printed tablet of ketamine HCl can be a promising candidate for management of refractory depressions and chronic pain. Additionally, the additive manufacturing method enables the production of patient-tailored dosage with tunable-release kinetics for personalized medicine in point-of care setting.

Nanoarchitectonics of doxycycline-loaded vitamin E-D-α-tocopheryl polyethylene glycol 1000 succinate micelles for ovarian cancer stem cell treatment.

Aim: This study aim to develop doxycycline within the D-α-tocopheryl polyethylene glycol 1000 succinate micelle platform as an anticancer stem cell agent. Materials & methods: The optimized nanomicelle formulation was prepared using the solvent casting method and evaluated through physicochemical and biological characterization. Results: Nanomicelles exhibited mean particle sizes of 14.48 nm (polydispersity index: 0.22) using dynamic light scattering and 18.22 nm using transmission electron micrography. Drug loading and encapsulation efficiency were 2% and 66.73%, respectively. Doxycycline-loaded micelles exhibited sustained release, with 98.5% released in 24 h. IC50 values were 20 µg/ml for free drug and 5 µg/ml for micelles after 48 h of cell exposure. A significant 74% reduction in CD44 biomarker and 100% colony formation inhibition were observed. Conclusion: Doxycycline in hemo/biocompatible nanomicelles holds potential for ovarian cancer stem cell therapy.

Cancer, a global leading cause of death, has a significant impact on human health. Among the various types of cancer, ovarian cancer ranks as the seventh most prevalent, posing a significant threat to women and contributing significantly to deaths in this population. Recent studies have highlighted the importance of targeting cancer stem cells to enhance the effectiveness of cancer treatments and prevent tumor relapse. Cancer stem cells are cells that can differentiate into different cell types in a tumor, driving the growth and spread of cancer. Over the past few decades, certain antibiotics, including doxycycline, have emerged as potent and selective anticancer stem cell agents by specifically targeting mitochondrial biogenesis. In line with this, the authors developed a doxycycline-loaded micelle delivery system. Micelles are spheres made of a single layer of a type of fat called phospholipids; they have been combined with drugs to increase the successful delivery and effectiveness of that drug. This research revealed that this micelle formulation demonstrated a fourfold increase in efficacy against ovarian cancer stem cells compared with free antibiotics. Moreover, it efficiently reduced colony formation and CD44 biomarker levels among the stem cells, indicating damage to cancer stem cells. These findings underscore the potential of this doxycycline-loaded micelle system as a promising approach for eradicating ovarian cancer stem cells and improving therapeutic outcomes.

3D printed pH-responsive tablets containing N-acetylglucosamine-loaded methylcellulose hydrogel for colon drug delivery applications.

The pH-responsive drug release approach in combination with three-dimensional (3D) printing for colon-specific oral drug administration can address the limitations of current treatments such as orally administered solid tablets. Such existing treatments fail to effectively deliver the right drug dosage to the colon. In order to achieve targeted drug release profiles, this work aimed at designing and producing 3D printed tablet shells using Eudragit® FS100 and polylactic acid (PLA) where the core was filled with 100 µl of N-acetylglucosamine (GlcNAc)-loaded methyl cellulose (MC) hydrogel. To meet the requirements of such tablets, the effects of polymer blending ratios and MC concentrations on physical, thermal, and material properties of various components of the tablets and most importantly in vitro drug release kinetics were investigated. The tablets with 80/20 wt% of Eudragit® FS100/PLA and the drug-loaded hydrogel with 30 mg/ml GlcNAc and 3% w/v MC showed the most promising results having the best printability, processability, and drug release kinetics besides being non-cytotoxic. Manufacturing of these tablets will be the first milestone in shifting from the conventional "one size fits all" approach to personalized medicine where different dosages and various combinations of drugs can be effectively delivered to the inflammation site.

Anti-inflammation-based treatment of atherosclerosis using Gliclazide-loaded biomimetic nanoghosts.

In the study, a biomimetic platform for anti-inflammatory-based treatment of atherosclerotic plaque was developed. Gliclazide (GL) as an anti-inflammasome agent was encapsulated in PLGA nanoparticles (NP), which were coated by monocyte membrane using an extrusion procedure. The size and zeta potential of the nanoghost (NG) changed to 292 and - 10 nm from 189.5 to -34.1 in the core NP. In addition, the actual size of 62.5 nm with a coating layer of 5 nm was measured using TEM. The NG was also showed a sustained release profile with the drug loading content of about 4.7%. Beside to attenuated TNFα, decrease in gene expression levels of NLRP3, MyD88, NOS, IL-1ß, IL-18 and caspases 1/3/8/9 in LPS-primed monocytes exposed to NG strongly indicated remarkable inflammation control. After systemic toxicity evaluation and pharmacokinetic analysis of NP and NG, intravenous NG treatment of rabbits with experimentally induced atherosclerosis revealed remarkably less plaque lesions, foam cells, lipid-laden macrophages, and pathological issues in tunica media of aorta sections. Higher expression of CD163 than CD68 in aorta of NG-treated rabbits strongly reveals higher M2/M1 macrophage polarization. The bio/hemocompatible, biomimetic and anti-inflammatory NG can be considered as a potential platform for immunotherapy of particularly atherosclerosis in the field of personalized medicine.

Additive Manufacturing of an Extended-Release Tablet of Tacrolimus.

An extended-release tablet of tacrolimus as once-daily dosing was fabricated using 3D printing technology. It was developed by combining two 3D-printing methods in parallel. Indeed, an optimized mixture of PVA, sorbitol, and magnesium stearate as a shell compartment was printed through a hot-melt extrusion (HME) nozzle while an HPMC gel mixture of the drug in the core compartment was printed by a pressure-assisted micro-syringe (PAM). A 3D-printed tablet with an infill of 90% was selected as an optimized formula upon the desired dissolution profile, releasing 86% of the drug at 12 h, similar to the commercial one. The weight variation, friability, hardness, assay, and content uniformity determination met USP requirements. A microbial evaluation showed that the 3D-printed tablet does not support microbial growth. SEM analysis showed smooth surfaces with multiple deposited layers. No peak interference appeared based on FTIR analysis. No decomposition of the polymer and drug was observed in the printing temperature, and no change in tacrolimus crystallinity was detected based on TGA and DSC analyses, respectively. The novel, sTable 3D-printed tablet, fabricated using controllable additive manufacturing, can quickly provide tailored dosing with specific kinetic release for personalized medicine at the point-of-care.

Design and Fabrication of a High Performance Microfluidic Chip for Blood Plasma Separation: Modelling and Prediction of System Behaviour via CFD Method.

This paper presents a single-step microfluidic system designed for passive separation of human fresh blood plasma using direct capillary forces. Our microfluidic system is composed of a cylindrical well between upper and lower channel pairs produced by soft photolithography. The microchip was fabricated based on hydrophobicity differences upon suitable cylindrical surfaces using gravitational and capillary forces and lateral migration of plasma and red blood cells. The plasma radiation was applied to attach the polymeric segment (polydimethylsiloxane (PDMS)) to the glass. Meanwhile, Tween 80 was used as a surfactant to increase the hydrophobicity of the lateral channel surfaces. This led to the higher movement of whole blood, including plasma. Fick's law of diffusion was validated for this diffusion transfer, the Navier-Stokes equation was used for the momentum balance, and the Laplace equation was utilized for the dynamics of the mesh. A model with high accuracy using the COMSOL Multiphysics software was created to predict the capillary forces and chip model validation. RBCs (red blood cells) were measured by the H3 cell counter instrument, by which 99% plasma purity was achieved. Practically, 58.3% of the plasma was separated from the blood within 12 min. Correlation between plasma separation results obtained from software and experimental data showed a coefficient of determination equal to 0.9732. This simple, rapid, stable, and reliable microchip can be considered as a promising candidate for providing plasma in point-of-care diagnostics.

Microfluidic synthesis of zoledronic acid loaded chitosan nanoparticles used for osteogenic differentiation of mesenchymal cells.

Zoledronic acid (ZA) is known as a potent bisphosphonate in osteogenic differentiation, but at high doses, it possesses toxic effects and causes decreased proliferation and differentiation of osteoblasts. Therefore, encapsulation of ZA into nanoparticles and control of its release is expected to promote differentiation of stem cells into osteoblasts. The present work aimed to develop a simple method for synthesis of monodisperse ZA-loaded chitosan (CS) nanoparticles. In this regard, we proposed a microfluidic synthesis of nanoparticles through the ionic cross-linking of CS in the presence of ZA without a crosslinker. The main advantages of these microfluidic generated nanoparticles were narrow size distribution and fine spherical shape. Conversely, the nanoparticles that were synthesized using a bulk mixing method had an irregular shape with a broad size distribution. Real-time PCR assay as well as alizarin red staining were used to evaluate the in-vitro osteogenic potential of the nanoparticles. The results indicated that the controlled release of ZA from the microfluidic system generated uniform nanoparticles, improving the osteogenic differentiation of mesenchymal stem cells. Additionally, this microfluidic device provided the well-controlled synthesis of novel nanoparticles with a modified CS macromolecular polymer for targeted drug delivery systems.

Development of osteon-like scaffold-cell construct by quadruple coaxial extrusion-based 3D bioprinting of nanocomposite hydrogel.

Despite advances in bone tissue engineering, fabricating a scaffold which can be used as an implant for large bone defects remains challenge. One of the great importance in fabricating a biomimetic bone implant is considering the possibility of the integration of the structure and function of implants with hierarchical structure of bone. Herein, we propose a method to mimic the structural unit of compact bone, osteon, with spatial pattern of human umbilical vein endothelial cells (HUVECs) and human mesenchymal stem cells (hMSCs) in the adjacent layers that mimic Haversian canal and lamella, respectively. To this end, coaxial extrusion-based bioprinting technique via a customized quadruple-layer core-shell nozzle was employed. 3D implant scaffold-cell construct was fabricated by using polyethylene glycol as a hollowing agent in the first layer, gelatin methacryloyl (GelMA) and alginate blended hydrogel encapsulating HUVEC cells with vascular endothelial growth factor nanoparticles in the second layer (vasculogenic layer) to mimic vascular vessel, and GelMA and alginate blended hydrogel containing hMSCs cells in the outer osteogenic layer to imitate lamella. Two types of bone minerals, whitlockite and hydroxyapatite, were incorporated in osteogenic layer to induce osteoblastic differentiation and enhance mechanical properties (the young's modules of nanocomposite increased from 35 kPa to 80 kPa). In-vitro evaluations demonstrated high cell viability (94 % within 10 days) and proliferation. Furthermore, ALP enzyme activity increased considerably within 2 weeks and mineralized extra cellular matrix considerably produced within 3 weeks. Also, a significant increase in osteogenic markers was observed indicating the presence of differentiated osteoblast cells. Therefore, the work indicates the potential of single step 3D bioprinting process to fabricate biomimetic osteons to use as bone grafts for regeneration.

Activation of androgen receptors alters hippocampal synaptic plasticity and memory retention through modulation of L-type calcium channels.

AIMS: It has been revealed that membrane androgen receptor activation modulates avoidance memory and synaptic plasticity. In a previous study, we showed that Calcineurin, a calcium dependent phosphatase, could be a potential mediator of these AR effects. Also, it is reported that AR activation leads to L-type calcium channel activation. The aim of the current study is to test whether L-type calcium channels are downstream of AR and whether this signal pathway mediates the impairment effect of androgenic steroids on passive avoidance memory and synaptic plasticity. MATERIALS AND METHODS: We measured the effect of Nandrolone Decanoate (AR agonist), AR antagonist (Nilutamide) plus ND or L-type calcium channel inhibitor (Nifedipine) plus ND on passive avoidance performance of adolescent male rats. For extracellular field potential recordings hippocampal slices were perfused with ND, Nilutamide-ND or Nifedipine-ND. KEY FINDINGS: Our results clarified that AR activation by ND could impair avoidance behavior as step through latency decreased in ND-treated group while application of both Nilutamide and Nifedipine reestablished normal avoidance behavior. Also, LTP induction in the CA1 area of hippocampus was diminished by ND perfusion and both AR antagonist and L-type calcium channel inhibitor application lead to normal LTP. These findings support our hypothesis that activation of L-type calcium channels are involved in ARs mechanism effects on both avoidance behavior and hippocampal synaptic plasticity. SIGNIFICANCE: Understanding the biological effects of AR agonists on cognitive processes and its cellular mechanism may be a new/supplementary way to treating fear-related disorders.

Size-dependent bioactivity of electrosprayed core-shell chitosan-alginate particles for protein delivery.

Nano-bio interactions are size-dependent. The present study investigates whether core-shell chitosan-alginate particle size governs biological activities as well as protein release profile. A coaxial electrospraying was used to fabricate bovine serum albumin (BSA)-loaded core-shell micro/nanoparticles and were fully characterized. The bio/hemocompatibility of the particles was assessed using MTT and hemolytic assays, respectively, followed by the uptake assessment using flow cytometry. Finally, protein absorption was investigated using SDS-PAGE. The SEM size of the microparticles, the hydrodynamic, and the actual sizes of the nanoparticles were 1.2 µm, 90.49 nm, and 50 nm, respectively. Interactions among two polymers and BSA were observed using DSC analysis. BET analysis showed a more surface area for nanoparticles. A sustained release trend of BSA was observed after 14- and 10-day for microparticles and nanoparticles, respectively. Microparticles exhibited excellent hemocompatibility (< 5% hemolysis) and cell viability (at least > 70%) in all concentrations. However, acceptable hemolytic activity and cell viability were observed for nanoparticles in concentrations below 250 µg/mL. Furthermore, nanoparticles showed greater cellular uptake (~ 4 folds) and protein absorption (~ 1.61 folds) than microparticles. Overall, the developed core-shell chitosan-alginate particles in the micro/nanoscale can be promising candidates for biomedical application and regenerative medicine regarding their effects on above mentioned biological activities.

Evaluating the Impact of the COVID-19 Pandemic on Accessing HIV Services in South Africa: A Systematic Review.

Progress has been made towards controlling the Human Immunodeficiency Virus (HIV) epidemic in South Africa. However, the emergence of coronavirus disease 2019 (COVID-19) has disrupted access to health care. This systematic review aims to evaluate the impact of the pandemic on accessing HIV services at a primary health care (PHC) level in South Africa. HIV services that have been significantly impacted are highlighted, and recommendations for future public health emergencies are made. Three databases were searched in January 2022. The studies included were those that reported on HIV services at a PHC level in South Africa. From the searches, 203 papers were identified, of which 34 full texts were screened. Eleven studies met the inclusion criteria and were included in this review. Overall, decreases in HIV testing, positive HIV tests, and initiation of antiretroviral therapy (ART) were reported. Resilience of ART provision was reported, meaning that adherence to treatment was sustained throughout the pandemic. The findings showed that HIV services at private PHC facilities were unaffected, however, an overall decrease in HIV services at public PHC facilities was reported, excluding antenatal care which showed resilience.

The application of 3D printing in preoperative planning for transcatheter aortic valve replacement: a systematic review.

BACKGROUND: Recently, transcatheter aortic valve replacement (TAVR) has been suggested as a less invasive treatment compared to surgical aortic valve replacement, for patients with severe aortic stenosis. Despite the attention, persisting evidence suggests that several procedural complications are more prevalent with the transcatheter approach. Consequently, a systematic review was undertaken to evaluate the application of three-dimensional (3D) printing in preoperative planning for TAVR, as a means of predicting and subsequently, reducing the incidence of adverse events. METHODS: MEDLINE, Web of Science and Embase were searched to identify studies that utilised patient-specific 3D printed models to predict or mitigate the risk of procedural complications. RESULTS: 13 of 219 papers met the inclusion criteria of this review. The eligible studies have shown that 3D printing has most commonly been used to predict the occurrence and severity of paravalvular regurgitation, with relatively high accuracy. Studies have also explored the usefulness of 3D printed anatomical models in reducing the incidence of coronary artery obstruction, new-onset conduction disturbance and aortic annular rapture. CONCLUSION: Patient-specific 3D models can be used in pre-procedural planning for challenging cases, to help deliver personalised treatment. However, the application of 3D printing is not recommended for routine clinical practice, due to practicality issues.

Nanobiosensor Based on Sugar Code-AuNPs Aggregation: A Key to Opening New Gates in Rapid Diagnosis of Streptococcal Pharyngitis.

Streptococcal pharyngitis is mainly caused by Streptococcus pyogenes (GAS), which if left untreated can lead to rheumatic heart disease. The accurate diagnosis of streptococcal pharyngitis is a challenge for clinicians because several symptoms of streptococcal pharyngitis are similar to viral pharyngitis. There are some commercially available biosensors for the rapid diagnosis of streptococcal pharyngitis. Nevertheless, they are not widely used by physicians, mainly because of their high price and dependence on the instrument. Serotype M1 GAS is the most prevalent cause of streptococcal pharyngitis and binds to H-1 antigen, a sugar code found on oral epithelial cells. Here, we present a nanobiosensor based on aggregation of H-1 antigen-conjugated gold nanoparticles for the rapid, qualitative, and quantitative detection of M1 GAS, which is inspired by the sugar code-lectin interaction. It is noteworthy that M1 GAS was detected in a wide concentration range (1 × 103-1×106 CFU/ml) with a linear response and a short detection time of 20 min. Good reproducibility, easy-to-use, and relatively low production cost are among other attractive features of this nanobiosensor. This work provides a strategic roadmap for developing a new generation of biosensors via targeting the sugar code-lectin interaction in future studies.

The effect of cryoprecipitate on prevention of intra cerebral hemorrhage and brain contusion expansion in traumatic patients.

BACKGROUND: Traumatic brain injury (TBI) is a general and socioeconomic complication and is one of the important causes of mortality and disability among young people in the world. Falling and violence and sports injuries are the other cause. It causes for about ten million new patients, accounting for 9% of all deaths. This interventional study aims to investigate the effects of early administration of cryoprecipitate to prevent expansion of intracranial hemorrhage. METHODS: This randomized clinical trial recruited 54 non-pregnant patients. 27 patients in the control group and 27patients in the interventional group. For all patients, common and accepted procedures in scientific centers, including anticonvulsant drugs, normal saline and the other routine management was done and only for patients in the intervention group, 4 units of cryoprecipitate were added to their routine treatments; computed tomography scan (CT) scan was performed 48 hours later in both groups and finally the contusion size was compared in both groups. RESULTS: It was observed in the intervention group that by adding 4 units of cryoprecipitate to their treatments; they had no increased size of the brain parenchymal contusion according to the criteria defined in the study compared to the control group (OR: 0.08, 95% CI: 0.0102_0.6303). CONCLUSIONS: According to a clinical trial, it seems that cryoprecipitate can prevent of cerebral parenchymal hemorrhage expansion in traumatic patients.

Genotoxicity assessment of amino zinc nanoparticles in wheat (Triticum aestivum L.) as cytogenetical perspective.

Nanoparticles have a positive impact in several subjects especially in agriculture, while their safety is still being debated. Numerous commercial nano pesticide, insecticides, and fertilizers products are found in the local markets without any intensely studies on the side effect of these products on plant, human as well as environmental effects. The present study aimed to evaluate the genotoxicity of commercial amino zinc nanoparticles (AZ NPs) on Triticum aestivum L. during seeds germination and root elongation using concentration ranges (50, 100, and 150 ppm) at different exposure times (8, 16 and 24 hrs). Long term exposure to AZ NPs, exhibited only slight variation in germination rates and the elongation of roots was affected by AZ NPs treatment ranged from 97.66 to 100%. Significant reduction in the mitotic index was 35.33% after 24 hrs and 150 ppm of AZ NPs, was also observed comparing with control which was 88.0%. Genotoxicity was evaluated at a cytological level in root meristems that revealed sever variations in mitotic activity, chromosomal aberrations, and micronuclei release. Results exhibited that nano amino zinc could enter effortlessly into the cells and inhibit the normal cellular function. The decrease in the emergence of chromosomal aberrations resulting from AZ NPs exposure in a dose-dependent manner was clearly indicated that AZ NPs has induced genotoxic effect on wheat root tips.

SPION based magnetic PLGA nanofibers for neural differentiation of mesenchymal stem cells.

Recently, magnetic platforms have been widely investigated in diagnostic, therapeutic and research applications due to certain properties, such as cell and tissue tracking and imaging, thermal therapy and being dirigible. In this study, the incorporation of magnetic nanoparticles (MNPs) in nanofibers has been proposed to combine the advantages of both nanofibers and MNPs to induce neural differentiation of mesenchymal stem cells. Magnetic poly (lactic-co-glycolic acid) nanofibers (containing 0%, 5% and 10% SPION) were fabricated and utilized as the matrix for the differentiation of mesenchymal stem cells (MSCs). Morphological, magnetic and mechanical properties were analyzed using FESEM, VSM and tensile test, respectively. The expression of neural markers (TUJ-1, NSE, MAP-2) was assessed quantitative and qualitatively utilizing RT-PCR and immunocytochemistry. Results confirmed the incorporation of MNPs in nanofibrous scaffold, presenting a saturation magnetization of 9.73 emu g-1. Also, with increase in magnetic particle concentration (0%-10%), tensile strength increased from 4.08 to 5.85 MPa, whereas the percentage of elongation decreased. TUJ-1 expression was 3.8 and 1.8 fold for 10% and 5% magnetic scaffold (versus non-magnetic scaffold) respectively, and the expression of NSE was 6.3 and 1.2-fold for 10% and 5%, respectively. Consequently, it seems that incorporation of magnetic biomaterial can promote the neural differentiation of MSCs, during which the augmentation of super paramagnetic iron oxide concentration from 0% to 10% accelerates the neural differentiation process.