651 research outputs found
Mesenchymal Stem Cells Modulate the Immune System in Developing Therapeutic Interventions
Mesenchymal stem cells (MSCs) are emerging as key players in regenerative medicine for the treatment of various diseases associated with the inflammation and degeneration, thereby aiding in therapeutic advancements. Several tissues have been identified as potential sources of MSCs including the bone marrow, cord blood, dental pulp, umbilical cord, adipose tissue, peripheral blood, and fetal liver, of which some are clinically recognized. MSCs are capable of differentiating into cells of multiple lineages and therefore established as suitable candidates for transplantation in damaged organs. They have added advantage of higher proliferation, easy expansion, and, more importantly, the absence of HLA class II receptors, with potential applications extending toward allogenic settings. MSCs are actively involved in different mechanisms related to repair and regeneration of tissues via immunomodulation, transdifferentiation, paracrine factors, etc. They are known to exhibit profound immunomodulatory effect on T and B cells and natural killer (NK) cells mediated via soluble factors and direct cell-cell contact. The MSCs activate the immune responses and inhibit proliferation, maturation, and differentiation of T and B cells. The MSC-activated immune responses induce the expression of regulatory T cells (Tregs). A plethora of studies have established that MSCs suppress immune responses via immunomodulation that makes them a preferred cell source for the use in clinical trials
COMPARISON OF COMPRESSIVE STRENGTH OF BULK FILLED COMPOSITE AND NANO HYBRID COMPOSITE- AN IN-VITRO STUDY.
Background During the past 60 years, the use of composite resin for direct restorations in anterior and posterior teeth has increased significantly, largely due to the esthetic demands of patients and concerns regarding mercury in amalgam fillings. Because composite resins require little to no preparation, minimally invasive procedures can be used to preserve tooth structure and provide natural-looking results. Dental composites typically are composed of three chemical materials: an organic matrix, an inorganic matrix, and a coupling agent. Today’s composite resins produce highly esthetic, long-lasting restorations for many indications. Through an understanding of advanced layering techniques, microleakage, and fracture rate concerns can be decreased significantly. Hence it is imperative to evaluate the compressive strength of bulk-filled composite and nanohybrid composite.Aims & Objectives To assess, evaluate and compare the compressive strength of Bulk filled composite and Nano Hybrid composite.
Materials and MethodsStudy method- In-vitro study
Sample A-Ivoclar Vivadent Inc. Bulk filled composite & Tetric N-Ceram Bulk Filled Composite (Leichtenstein).Sample B-Ivoclar Vivadent Nano filled composite & Tetric N- Ceram Nano Hybrid Composite (Leichtenstein).The cylindrical specimens were transferred onto the Instron testing machine (Model H50KS; Instron,Redhill, Surrey,RH15DZ, UK) individually and subjected to compressive testing at a crosshead speed of 1.0 mm/minute.Results:
A comparison of the compressive strength of the individual groups was done. There was a statistically significant difference between the groups pertaining to compressive strength. The mean score for Group B was more than Group A.ConclusionsWithin the limitation of the specific materials, testing methods, and in-vitro environment in the study, it is concluded that Nanohybrid composite material has better compressive strength as compared to bulk fill composite.
RecommendationsFurther studies are needed to determine the optimal curing light intensity to obtain the best results in terms of mechanical properties for newer bulk-fill composite materials
3D Culturing of Stem Cells: An Emerging Technique for Advancing Fundamental Research in Regenerative Medicine
Regenerative medicine has been coming into spotlight ever since the realisation that conventional treatments are not enough, and the need for specific therapies has emerged. This, however, has paved way for cell-free therapy using extracellular vesicles. A two-dimensional (2D) cell culture model is widely recognised as the “gold standard” for researching cellular communications ex vivo. Although the 2D culture technique is straightforward and easy to use, it cannot replicate the in vivo ECM interactions & microenvironment. On the contrary, 3D culture culturing technology has emerged which include structures such as spheroids and organoids. Organoids are small replicas of in vivo tissues and organs, which faithfully recreate their structures and functions. These could be used as models to derive stem cells based EVs for manufacturing purposes. The linkages between infection and cancer growth, as well as mutation and carcinogenesis, may be modelled using this bioengineered platform. All in all, 3D culturing derived EVs serves as a novel platform for diagnostics, drug discovery & delivery, and therapy
Mechanisms of Action of Human Mesenchymal Stem Cells in Tissue Repair Regeneration and their Implications
Cell replacement therapy holds a promising future in the treatment of degenerative diseases related to neuronal, cardiac and bone tissues. In such kind of diseases, there is a progressive loss of speciï¬c types of cells. Currently the most upcoming and trusted cell candidate is Mesenchymal Stem Cells (MSCs) as these cells are easy to isolate from the tissue, easy to maintain and expand and no ethical concerns are linked. MSCs can be obtained from a number of sources like bone marrow, umbilical cord blood, umbilical cord, dental pulp, adipose tissues, etc. MSCs help in tissue repair and regeneration by various mechanisms of action like cell differentiation, immunomodulation, paracrine effect, etc. The future of regenerative medicine lies in tissue engineering and exploiting various properties to yield maximum output. In the current review article, we have targeted the repair and regeneration mechanisms of MSCs in neurodegenerative diseases, cardiac diseases and those related to bones. Yet there is a lot to understand, discover and then understand again about the molecular mechanisms of MSCs and then applying this knowledge in developing the therapy to get maximum repair and regeneration of concerned tissue and in turn the recovery of the patient
Differentiation Of Mesenchymal Stem Cells (Mscs) To Functional Neuron On Graphene-Polycaprolactone Nanoscaffolds
Spinal cord is an important part of the central nervous system that controls all activities of the body. It is a tubular bundle of nerve fibers and tissues connecting brain to nearly all parts of the body. Nerve cells in an adult human body do not divide and make copies of themselves. Therefore, in case of an injury or damage to any part of spinal cord causes permanent changes to strength, sensation and other body functions. The field of tissue engineering and regenerative medicine which aims to replace and repair damaged tissues, organs or cells entails for effective methods for fabricating biological scaffolds. Here we present synthesis of fibrous scaffolds by a process called electrospinning that can provide a microenvironment in-vitro for differentiation and proliferation of functional neurons from mesenchymal stem cells. These nanofibrous PCL scaffolds with graphene as filler materials are engineered in such a way so as to provide topological, biochemical as well as electrical cues that can enhance neurite extension and penetration. Poly(ε-caprolactone) (PCL) is a FDA approved synthetic biodegradable polyester extensively used in biomedical applications. Graphene, a single layer carbon crystal, based nanomaterials have recently gained considerable interest for tissue engineering applications including osteogenic, neural and differentiation in other lineages due to their favorable chemical, electrical and mechanical properties. Our final aim is that the functional tissues or organs developed in vitro shall be implanted inside body to rehabilitate the biological function that was lost due to injury, abnormality or loss
First record of a Leucosid crab<em> Paranursia abbreviata</em> Bell, 1855 from Devi estuary, Odisha Coast, India
117-119A leucosid crab Paranursia abbreviata Bell, 1855 is recorded for the first time from Odisha albeit from coastal waters of the Indian peninsula after half a century. Present study is an effort towards documentation of the species from Odisha, indicative of a range extension between the Coromandal coast and Gulf of Martaban, Myanmar
Optimization of saccharification prospective from starch of sweet potato roots through acid-enzyme hydrolysis : structural, chemical and elemental profiling
The sweet potato root, a potent source of starch which is being considered as an effi cient alternative for fuel ethanol production in recent times. The starchy substrate needs to be subsequently dextrinized and saccharifi ed so as to enhance the utilization of its carbohydrates for ethanol production. In the present investigation, acid-enzyme process was conducted for the dextrinization and saccharifi cation of sweet potato root fl our (SPRF). The best optimized condition for dextrinization was achieved with an incubation period of 60 min, temperature 100 ºC and 1M HCl. However, for saccharifi cation, the best result was obtained with an incubation of 18 h, pH 4, temperature 65 ºC and 1000 U concentration of Palkodex®. After the dextrinization process, maximum concentrations of total sugar and hydroxymethylfurfural (HMF) [380.44 ± 3.17 g/kg and 13.28 ± 0.25 mg/g, respectively] were released. Nevertheless, after saccharifi cation, 658.80 ± 7.83 g/kg of total sugar was obtained which was about 73% more than that of dextrinization. After successful dextrinization and saccharifi cation, the structural, chemical and elemental analysis were investigated using techniques such as scanning electron microscopy (SEM), Fourier-transforms infrared spectroscopy (FTIR) and energy-dispersive X-ray fl uorescence spectrophotometer (EDXRF), respectively. Eff ective hydrolysis was demonstrated in thin layer chromatography (TLC) where the HCl was able to generate monomeric sugar such as glucose and maltose. On the other hand, only glucose is synthesized on the mutual eff ect of HCl and Palkodex®. The SEM fi ndings indicate that the rough structure of both dextrinized and saccharifi ed sample was gained due to the vigorous eff ect of both acid and enzyme subsequently. The saccharifi ed SPRF when subjected to fermentation with Saccharomyces cerevisiae and Zymomonas mobilis separately, it was observed that Z. mobilis produced more stretching vibration of –OH than S. cerevisiae, which evidenced the better production of bioethanol. Additionally, evaluation of the infl uence of S. cerevisiae and Z. mobilis through elemental analysis revealed upsurge in the concentrations of S, Cl, Ca, Mn, Fe and Zn and decline in the concentrations of P, K and Cu in the fermented residue of S. cerevisiae and Z. mobilis, however, Z. mobilis showed little more variation than that of S. cerevisiae
GPR56 Regulates VEGF Production and Angiogenesis during Melanoma Progression
2012 February 15Angiogenesis is a critical step during cancer progression. The VEGF is a major stimulator for angiogenesis and is predominantly contributed by cancer cells in tumors. Inhibition of the VEGF signaling pathway has shown promising therapeutic benefits for cancer patients, but adaptive tumor responses are often observed, indicating the need for further understanding of VEGF regulation. We report that a novel G protein–coupled receptor, GPR56, inhibits VEGF production from the melanoma cell lines and impedes melanoma angiogenesis and growth, through the serine threonine proline-rich segment in its N-terminus and a signaling pathway involving protein kinase Cα. We also present evidence that the two fragments of GPR56, which are generated by autocatalyzed cleavage, played distinct roles in regulating VEGF production and melanoma progression. Finally, consistent with its suppressive roles in melanoma progression, the expression levels of GPR56 are inversely correlated with the malignancy of melanomas in human subjects. We propose that components of the GPR56-mediated signaling pathway may serve as new targets for antiangiogenic treatment of melanoma. Cancer Res; 71(16); 5558–68.National Institutes of Health (U.S.) (U54CA126515)Howard Hughes Medical Institut
Identification and Functional Characterization of N-Terminally Acetylated Proteins in Drosophila melanogaster
A new study reveals a functional rule for N-terminal acetylation in higher eukaryotes called the (X)PX rule and describes a generic method that prevents this modification to allow the study of N-terminal acetylation in any given protein
Comparative Functional Analysis of the Caenorhabditis elegans and Drosophila melanogaster Proteomes
The nematode Caenorhabditis elegans is a popular model system in genetics, not least because a majority of human disease genes are conserved in C. elegans. To generate a comprehensive inventory of its expressed proteome, we performed extensive shotgun proteomics and identified more than half of all predicted C. elegans proteins. This allowed us to confirm and extend genome annotations, characterize the role of operons in C. elegans, and semiquantitatively infer abundance levels for thousands of proteins. Furthermore, for the first time to our knowledge, we were able to compare two animal proteomes (C. elegans and Drosophila melanogaster). We found that the abundances of orthologous proteins in metazoans correlate remarkably well, better than protein abundance versus transcript abundance within each organism or transcript abundances across organisms; this suggests that changes in transcript abundance may have been partially offset during evolution by opposing changes in protein abundance
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