Effect of ethanolic extract of beet roots and leaves on motor coordination in male Wistar rats

زمینه و هدف: عدم تعادل حرکتی در اثر عوامل مختلفی از جمله ضایعات مغزی عصبی، مشکلات عضلانی، کم خونی و مصرف داروها رخ می دهد. گیاه چغندر با نام علمی Beta vulgaris L. دارای اثرات متنوع از جمله اثرات ضد التهابی، آنتی اکسیدانی، ضد استیل کولین استرازی و کاهش قند خون می باشد که در این مطالعه اثر عصاره اتانولی برگ و ریشه این گیاه بر تعادل حرکتی بررسی شده است. روش بررسی: در این مطالعه تجربی عصاره اتانولی ریشه و برگ گیاه چغندر به روش ماسراسیون تهیه شد. موش های صحرایی نر بالغ به طور تصادفی در 7 گروه 8 تایی تقسیم شدند و به مدت 25 روز آب مقطر، دوزهای مختلف عصاره ریشه (250،500 و mg/kg1000) و برگ چغندر (50 و mg/kg100) را به صورت داخل صفاقی دریافت کردند. روز 26، نیم ساعت بعد از آخرین تزریق قدرت حفظ تعادل حرکتی موش ها به وسیله روتارود اندازه گیری شد. یافته ها: عصاره ریشه چغندر در دوزهای 500 و mg/kg1000 سبب افزایش معنی دار در تعادل حرکتی شد (p0.05). نتیجه گیری: عصاره های ریشه و برگ گیاه چغندر باعث بهبود فعالیت حرکتی در موش های صحرایی نر بالغ می شود

Effect of Single Selection Method on Woody and Herbaceous Plant Biodiversity in Khalil-Mahale Forest, Behshahr

This study was undertaken to investigate the role of forest management in tree diversity, regeneration and vegetation in control and managed parcels of series No. 1 of forestry plan in Khalil-Mahale, Behshahr. Thirty samples with an area of 1000 m2 were systematically and randomly taken with a 100 × 75 m grid in both parcels. In each plot, tree number and species type were recorded. In order to study the vegetation, five micro-plots (1 m2), one in the center and four others in four main directions (half radius from the center of the plot) were taken in each plot. The type and percentage of herbaceous species were recorded in each microplot. To count the regeneration in the center of the main plot, circular sample plots with an area of 100 m2 were used. To study and compare the biodiversity in the two plots and to calculate the richness and evenness, the Simpson and Shannon-Wiener diversity indices, Margalef and Menhinic indices and the Pilo index were used, respectively, using PAST software. The results showed that the number of plant species was more in managed plots. The biodiversity of woody and herbaceous plants richness indices and regeneration of tree species were higher in managed plots. In fact, the results showed that forest management using single selection method had different effects on woody species regeneration and diversity of herbaceous and tree species

A Simple and Efficient Method to Improve Mechanical Properties of Collagen Scaffolds by UV Irradiation

Collagen is the major protein component of cartilage, bone, skin and connective tissue and constitutes the major part of the extracellular matrix. Collagen type I has complex structural hierarchy, which consists of treepolypeptide α-chains wound together in a rod-like helical structure. Collagen is an important biomaterial, finding many applications in the field of tissue engineering. It has been processed into various shapes, such as, gel, film, sponge and fiber. It is commonly used as the scaffolding material for tissue engineering due to its many superior properties including low antigenicity and high growth promotion. Unfortunately, poor mechanical properties and rapid degradation rates of collagen scaffolds can cause instability and difficulty in handling. By crosslinking, the structural stability of the collagen and its rate of resorption can be adapted with respect to its demanding requirements. The strength, resorption rate, and biocompatibility of collagenous biomaterials are profoundly influenced by the method and extent of crosslinking. In thisstudy, the effect of UV irradiation on collagen scaffolds has been carried out.Collagen scaffolds were fabricated using freeze drying method with freezing temperature of -80oC, then exposed to UV irradiation. Mean pore size of the scaffolds was obtained as 98.52±14.51 μm using scanning electron microscopy. Collagen scaffolds exposed to UV Irradiation (254 nm) for 15 min showed the highest tensile strain (17.37±0.98 %), modulus (1.67±0.15 MPa) and maximum load (24.47±2.38 cN) values. As partial loss of the native collagen structure may influence attachment, migration, and proliferation of cells on collagen scaffolds, we detected no intact α-chains after SDS-Page chromatography. We demonstrate that UV irradiation is a rapid and easily controlled means of increasing the mechanical strength of collagen scaffolds without any molecular fracture

The effects of Nano-Fe2O3 on the mechanical, physical and microstructure of cementitious composites

In this study, properties of cement composites and mortars were investigated in presence of Nano-Fe2O3 as their modifier. Cement composites were synthesized using the sol-gel method with tetraethylammonium orthosilicate as the complex legend. Subsequently, Nano-Fe2O3 was added at 2, 4, and 6 wt% dosages to the cement composite, while for mortars 2, 3 and 4 wt% of Nano-Fe2O3 dosages were used. FTIR and XRD tests were conducted to analyze the phase composition, molecular, and microstructure of cement composites, additionally, the effects of adding Nano-Fe2O3 on compressive and flexural strengths of mortars were investigated. The results indicated a change in the phase composition of the molecular-structure of cement composites, leading to stronger bonds in silicate network with more ordered arrangement in the presence of nanoparticles. The formation of three-membered silicate rings was also evident in composite samples containing higher amounts of Nano-Fe2O3 (i.e. 4 and 6 wt%). The microstructure analysis revealed that samples with Nano-Fe2O3 had a denser structure with a smaller pore size in comparison with control samples. The mechanical performance of mortar samples were enhanced with the incorporation of Nano-Fe2O3, where 3 wt% dosage was identified as the optimum

Behaviour of Human Induced Pluripotent Stem Cell-Derived Neural Progenitors on Collagen Scaffolds Varied in Freezing Temperature and Laminin Concentration Citation: Seeding hiPSC-NPs on Collagen Scaffolds

Abstract Objective: Biomaterial technology, when combined with emerging human induced pluripotent stem cell (hiPSC) technology, provides a promising strategy for patient-specific tissue engineering. In this study, we have evaluated the physical effects of collagen scaffolds fabricated at various freezing temperatures on the behavior of hiPSC-derived neural progenitors (hiPSC-NPs). In addition, the coating of scaffolds using different concentrations of laminin was examined on the cells. Materials and Methods: Initially, in this experimental study, the collagen scaffolds fabricated from different collagen concentrations and freezing temperatures were characterized by determining the pore size, porosity, swelling ratio, and mechanical properties. Effects of cross-linking on free amine groups, volume shrinkage and mass retention was also assessed. Then, hiPSC-NPs were seeded onto the most stable three-dimensional collagen scaffolds and we evaluated the effect of pore structure. Additionally, the different concentrations of laminin coating of the scaffolds on hiPSC-NPs behavior were assessed. Results: Scanning electron micrographs of the scaffolds showed a pore diameter in the range of 23-232 μm for the scaffolds prepared with different fabrication parameters. Also porosity of all scaffolds was >98% with more than 94% swelling ratio. hiPSC-NPs were subsequently seeded onto the scaffolds that were made by different freezing temperatures in order to assess for physical effects of the scaffolds. We observed similar proliferation, but more cell infiltration in scaffolds prepared at lower freezing temperatures. The laminin coating of the scaffolds improved NPs proliferation and infiltration in a dose-dependent manner. Immunofluorescence staining and scanning electron microscopy confirmed the compatibility of undifferentiated and differentiated hiPSC-NPs on these scaffolds. Conclusion: The results have suggested that the pore structure and laminin coating of collagen scaffolds significantly impact cell behavior. These biocompatible three-dimensional laminin-coated collagen scaffolds are good candidates for future hiPSC-NPs biomedical nerve tissue engineering applications

Exosome-inspired targeting of cancer cells with enhanced affinity

One of the major challenges in the area of novel drug delivery systems (NDDSs) is finding distinguished ligands for specific receptors represented by many cancer cells in order to enhance their cancer homing efficacy. Exosomes, the so-called natural nanocarriers or "Trojan horses,'' are secreted by the majority of cancer cells. These carriers exchange biomolecular information (e.g. proteins, siRNA, enzymes) between cancer cells and their stromal compartments in order to adjust a variety of cellular behaviours, including metastasis, apoptosis in T cells and angiogenesis. By exhibiting exosomal smart functions and biomimetic traits, exosome-mimicking nanocarriers will be one step ahead of the conventional targeted DDSs for the efficient delivery of antitumor drugs. In the present study, we tried to describe an engineering route to make some surface-functionalized nanoparticles that can mimic the targeting mechanism recruited by tumor-derived exosomes. The ligand-receptor interactions were investigated by molecular dynamics (MD) simulations. In addition, the selected ligand was experimentally studied to verify its improved targeting efficacy. The present study describes a novel targeting method that forces the mucin-domain-containing molecule-4 (TIM4)-embellished nanoparticles (NPs) to swarm towards the cancerous cells. These NPs can interact with the phosphatidylserine (PS) receptor on the surface of several kinds of cancer cells, such as U-87 MG (glioblastoma cell line). The molecular affinity between TIM4 as a homing device and PS, the target receptor, was investigated using MD simulations and surface plasmon resonance (SPR). According to the calculated free energies and the cellular uptake of TIM4-functionalized NPs, it seems that the TIM4/PS complex releases enough free energy to induce endocytosis. Our results emphasize on the potential of the proposed ligand as a good candidate for many targeted drug delivery applications. In this report, we present our proof-of-concept results in order to spotlight the importance of using computer-based simulating methods at the molecular level for the next-generation nanomedicine

Network Influence Based Classification and Comparison of Neurological Conditions

Variations in the influence of brain regions are used to classify neurological conditions by identifying eigenvector-based communities in connectivity matrices, generated from resting state functional magnetic resonance imaging scans. These communities capture the network influence of each brain region, revealing that the subjects with Alzheimer’s disease (AD) have a significantly lower degree of variation in their most influential brain regions when compared with healthy control (HC) and amnestic mild cognitive impairment (aMCI) subjects. Classification of subjects based on their pattern of influential regions is demonstrated with neural networks identifying HC, aMCI and AD subjects. The difference between these conditions are investigated by altering brain region influence so that a neural network changes a subject’s classification. This conversion is performed on healthy subjects changing to aMCI or AD, and for aMCI subjects changing to AD. The results highlight potential compensatory mechanisms that increase functional activity in certain regions for those with aMCI, such as in the right parahippocampal gyrus and regions in the default mode network, but these same regions experience significant decline in those that convert from aMCI to AD