Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Centre for Biomaterials, Cellular and Molecular Theranostics

Diagnosis of oral cancer using pathology is becoming more dependent on digital imaging. Since precancerous conditions like Oral submucous fibrosis originate in the basal layer of the tissue, it is very important to investigate the cell nuclei of the basal layer in Haematoxylin and Eosin stained tissue as it contains diagnostically important information. For that, accurate identification and segmentation of the nuclei is imperative. Our algorithm uses differential contrast enhancement and distance map transformations to segment out the cell nuclei in ImageJ Software. The algorithm performed successfully on high magnification images with high speed and relative simplicity thus proving its credibility. The nuclear attributes like entropy, polarity, and compactness are calculated and the values obtained are then statistically analyzed using Mann-Whitney U Test using SPSS Software to differentiate between normal and OSF(with severe dysplasia and without dysplasia). The results showed that in case of entropy, statistical significant difference (\mathbf{p} &lt; \pmb{0.0001}) is present between all the above mentioned three classes but in cases of compactness and polarity, statistical significant differences are present between normal and diseased classes, but not between OSF (without dysplasia) and OSF (with severe dysplasia) cases for both attributes (\mathbf{p}=\pmb{0.1527} for compactness and \mathbf{p}\pmb{=0.6965} for polarity). © 2018 IEEE.

VIT Unitversity

World University root node

Vellore Campus

2018 International Conference on Current Trends towards Converging Technologies (ICCTCT)

Nuclear Segmentation and its Quantification in H&amp;E Stained Images of Oral Precancer to Detect its Malignant Potentiality

Cytopathology

Detection and analysis of abnormal nuclear changes in oral cytological smears by Papanicolaou staining

Objectives: Dental composite resins with better biocompatibility and osteoconductivity have been sought in endodontic treatments. This study aimed to develop a technique to produce the osteoconductive resin surfaces through calcium phosphate (CaP) coating using a laser-assisted biomimetic (LAB) process. Methods: Light-cured, acrylic-based composite resins were used as substrates. The resin substrate was subjected to a LAB process comprising Nd:YAG pulsed laser irradiation in a supersaturated CaP solution. The LAB-processed substrate was immersed for 3 days in a simulated body fluid (SBF) for the preliminary osteoconductivity assessment. Results: After irradiation for 30 min, the resin surfaces were partly coated with a newly formed CaP layer. The coating layer contained hydroxyapatite as the main crystalline phase and the coating coverage depended on the laser wavelength and the type of resin. The LAB-processed CaP-coated surface exhibited apatite-forming ability in SBF. Conclusions: LAB process is effective for CaP coating on light-cured dental composite resins and improving their osteoconductivity. Clinical significance: The LAB process is a potential new tool to create a cementum-like osteoconductive surface on dental composite resins. © 2018 The Authors

Fulltext

Heliyon

Calcium phosphate coating on dental composite resins by a laser-assisted biomimetic process

Pre-sintered zirconia is preferred as a restoration material in dental applications due to its excellent strength and fracture toughness. When abrasive processes were used to obtain the required shape of (Y-TZP) yttria-stabilized tetragonal pre-sintered zirconia, it resulted in material strength degradation in the presence of coolant. Therefore, experiments were carried out on pre-sintered zirconia with diamond grinding wheel to evaluate the performance of cooling conditions such as dry, wet and minimum quantity lubrication (MQL). The effects of different environments on the grinding performance were studied based on the temperature distribution, phase transformation, flexural strength, microhardness and edge chipping damage. The Raman spectroscopy and X-ray diffraction analysis were used to estimate the quantity of monoclinic phase in pre-sintered zirconia. The temperature rise of the workpiece material during the grinding experiment was not higher and insufficient to cause the thermal stresses. The microstructural changes induced by grinding under different cooling strategies were associated with the quantitative assessment of monoclinic phase. The flexural strength of ground components was improved in the dry condition compared to the other process due to the absence of the defective layer and the occurrence of Y 3+ ions segregation. After grinding, there was a slight decrease in the hardness value by (1–8 HV), which was due to the formation of microcracks in the subsurface layer of the ground surface. In addition, to ensure the presence of microcracks, the edge chipping depth was measured. The damage depth obtained from the wet condition showed a higher value of 30 µm compared to the dry and MQL conditions. © 2018 Elsevier Ltd

Journal of the Mechanical Behavior of Biomedical Materials

Effect of grinding on subsurface modifications of pre-sintered zirconia under different cooling and lubrication conditions

We demonstrate facile and green synthesis of gold deposited zein nanoshells (AuZNS) using environmental benign solvent ethanol. Water soluble glycol chitosan is used for stabilization as well as for cationic functionalization of zein nanoparticles. Gold deposition is performed via ex-situ method at ambient conditions. AuZNS is of size around 100 nm and shows high inertness and biocompatibility even at double the therapeutic dosage. The absorbance is tuned at 808 nm for imaging-guided plasmonic photothermal therapy of cancer. Highly effective killing of cancer cells irrespective of their chemorefractory status is noticed at a very low therapeutic dosage of 25 μg and 5 min of biologically acceptable (500 mW) 808 nm laser irradiation. AuZNS also exhibit better X-ray attenuation in comparison to the commercially available iodine based contrast agent. © 2018 Elsevier B.V.

Materials Science and Engineering C

Facile synthesis of plasmonic zein nanoshells for imaging-guided photothermal cancer therapy

Surface functionalization of teeth with fluoride-incorporated apatite layers displays great potential in treatments and prevention of dental disorders. In this study, we used a sintered hydroxyapatite (sHA) substrate as a model material of teeth, and established a rapid and area-specific coating technique of fluoride-incorporated apatite layers by using a laser-assisted biomimetic (LAB) process. In this technique, a sHA substrate was irradiated on the surface with a Nd:YAG pulsed UV laser for 30 min in supersaturated calcium phosphate (CaP) solutions with various fluoride concentrations. The fluoride concentration in the CaP solution was varied to control morphology, crystalline structure, and fluoride content of the resulting layers. Without fluoride in the CaP solution, an octacalcium phosphate (OCP) layer with a flake-like structure was formed on the laser-irradiated surface of the substrate. The addition of fluoride (1000 µM and 3000 µM) to the CaP solution led to the formation of fluoride-incorporated apatite layers with an enamel-like needle-like nanostructure. The fluoride-incorporated apatite layers adhered firmly to the sHA surface and reduced acid dissolution of the sHA substrate by acting as a protective covering. Additionally, the layers released fluoride ions for more than 24 h, and exhibited antibacterial activity relative to a caries-causing bacterium, namely Streptococcus mutans. Thus, our LAB process can potentially act as a new tool for functionalization of tooth surfaces. Statement of Significance: We used a sintered hydroxyapatite (sHA) substrate as a model material of teeth, and established a rapid and area-specific coating technique of fluoride-incorporated apatite layers on the sHA surface by using our laser-assisted biomimetic (LAB) process. In this process, pulsed laser was utilized to accelerate seeded crystal growth in supersaturated calcium phosphate solutions supplemented with NaF. The thus-fabricated fluoride-incorporated apatite layers consisted of enamel-like needle-like nanocrystals with c-axis orientation. These fluoride-incorporated apatite layers adhered firmly to the sHA surface, reduced acid dissolution of the sHA substrate by acting as a protective covering, and exhibited antibacterial activity against Streptococcus mutans through the fluoride release. Thus, our LAB process can potentially act as a new tool for functionalization of tooth surfaces. © 2018 Acta Materialia Inc.

Acta Biomaterialia

Rapid and area-specific coating of fluoride-incorporated apatite layers by a laser-assisted biomimetic process for tooth surface functionalization

Zirconia-based ceramics are the most preferred materials used in implants due to their excellent mechanical properties compared with other alternatives. These materials available in the pre-sintered form are appropriate to grind due to their soft nature. However, it is challenging to achieve a required surface finish in grinding these ceramic materials owing to chipping, which limits its usage in industries. In this work, the pre-sintered yttria stabilized tetragonal zirconia (Y-TZP) component was ground using a resin-bonded diamond-grinding wheel under different cooling environments. The components ground under the minimum quantity lubrication conditions exhibited a reduced grinding force with better surface finish compared to wet (flood coolant) and dry conditions. The resultant specific energy was reduced with the increase in maximum chip thickness for different cooling conditions. The critical depth of cut estimated from the pre-sintered zirconia was witnessed to be higher, which indicated that the initiation of ductile to brittle transition occurred at a deeper depth of cut. The material removal mechanism observed in the pre-sintered zirconia was dominated by brittle fracture. This was evident from the obtained chips and ground surface morphology. © 2017 Taylor & Francis.

Materials and Manufacturing Processes

Study on grinding of pre-sintered zirconia using diamond wheel

Bacterial fish diseases caused by pathogenic organisms hamper aquaculture production and are responsible for considerable economic losses. Improperly sanitized hatcheries and fish cages with high stocking density are also responsible for causing fish diseases. Plant based natural products such as seaweeds are one of the effective alternative nutraceutical sources having antimicrobial property. The formulated extracts containing bioactive compounds are now being widely used because of their antibacterial activities. Seaweeds are rich in secondary metabolites and have a wide range of biological and medicinal properties. In this study biocompatible and biodegradable polymer Polycaprolactone (PCL) nonwoven nanofibrous membranes were fabricated. Antibacterial compounds extracted from the seaweed Sargasum longifolium and characterized for its antibacterial activity against fish pathogen were incor porated in to these membranes. The compounds with antibacterial activity were isolatet and purified through chromatography and characterized to detect the presence of bioactive antibacterial compounds and also to study their antibacterial activity against Aeromonas salmonicida. I addition their biological activities were also studied. The ethanol extract of S. longifolium was found to be effective against A. salmonicida. These preliminary findings confirm the efficiency of the S. longifolium bioactive compounds mediated nano fiber formulation for the treatment of A. salmonicida infection in fishes. Copyright © 2018 American Scientific Publishers All rights reserved.

Centre for Nanobiotechnology

Journal of Bionanoscience

Antibacterial Activity of Sargasum longifolium-Polycaprolactone Nanobiocomposite for Fish Pathogen

Although peptides, antibodies/antibody fragments, siRNAs, antisense DNAs, enzymes, and aptamers are all under development as possible therapeutic agents, the breadth of their applications has been severely compromised by their inability to reach intracellular targets. Thus, while macromolecules can often enter cells by receptor-mediated endocytosis, their missions frequently fail due to an inability to escape their entrapping endosomes. In this paper, we describe a general method for promoting release of any biologic material from any entrapping endosome. The strategy relies on the fact that all nascent endosomes contain extracellular (Na + -enriched) medium, but are surrounded by intracellular (K + -enriched) fluid in the cytoplasm. Osmotic swelling and rupture of endosomes will therefore be facilitated if the flow of K + down its concentration gradient from the cytosol into the endosome can be facilitated without allowing downhill flow of Na + from the endosome into the cytosol. While any K + selective ionophore can promote the K + specific influx, the ideal K + ionophore will also exchange influxed K + for an osmotically inactive proton (H + ) in order to prevent buildup of an electrical potential that would rapidly halt K + influx. The only ionophore that catalyzes this exchange of K + for H + efficiently is nigericin. We demonstrate here that ligand-targeted delivery of nigericin into endosomes that contain an otherwise impermeable fluorescent dye can augment release of the dye into the cell cytosol via swelling/bursting of the entrapping endosomes. We further show that nigericin-facilitated escape of a folate-targeted luciferase siRNA conjugate from its entrapping endosomes promotes rapid suppression of the intended luciferase reporter gene. Taken together, we propose that ionophore-catalyzed entry of K + into endosomal compartments can promote the release of otherwise impermeable contents from their encapsulating endosomes. © 2018 American Chemical Society.

Bioconjugate Chemistry

New Mechanism for Release of Endosomal Contents: Osmotic Lysis via Nigericin-Mediated K + /H + Exchange

Titanium oxide (TiO2) and zinc oxide (ZnO) composite structured nanoparticles were prepared by combining a sol-gel process and a solvothermal method. Titanium (IV) isoproxide (TTIP), used as a TiO2 precursor, was dissolved in a colloidal ZnO nanoparticle solution synthesized by the sol-gel method, and TiO2 was synthesized via solvothermal synthesis onto the ZnO nanoparticles. The effects of reaction conditions such as pH, reaction temperature, and reaction time on the morphology of the composite nanoparticles and the ultraviolet (UV) absorbance of their polymer composite films were investigated. The UV absorption of the poly(vinyl alcohol) (PVA) composite film with TiO2-coated ZnO nanoparticles was higher than that of the TiO2, ZnO, and ZnO-coated TiO2 composite films. The reaction pH was found to have the strongest influence on the UV absorbance of the PVA/(TiO2/ZnO) composite film. A pH of 7.0, reaction temperature of 250 °C, and reaction time of 24 h were the optimum conditions for UV absorption. © 2018, The Korean Fiber Society and Springer Nature B.V.