Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 13 de 13
Filter
1.
Nanoscale Adv ; 3(10): 2887-2901, 2021 May 18.
Article in English | MEDLINE | ID: mdl-36134187

ABSTRACT

The morphology of a nanoparticle strongly controls the path of electronic interaction, which directly correlates with the physicochemical properties and also the electrochemical comportment. Combining it with a two-dimensional (2D) material for a layer-by-layer approach will increase its possibilities in applications such as energy conversion and storage. Here, two different morphologies of MnFe2O4, nanoparticles and nanoneedles, are developed by a facile hydrothermal approach and sandwiched with reduced graphene oxide for constructing a 2D/3D sandwiched architecture. The rGO planar structure with abundant hierarchical short pores facilitates the thorough utilization of the utmost surface area to permeate the electrolyte within the structure to minimize the accumulation of rGO nanosheets laterally. The ferrite composited with rGO manifests high specific capacitance as the EDLC behaviour surpasses the faradaic pseudocapacitance boosting electrical conductivity compared to the as-synthesized MnFe2O4 structures. Benefiting from a 3D structure and the synergetic contribution of the MnFe2O4 nanoneedles and electrically conductive rGO layer, the MnFe2O4 nanoneedles@rGO electrode exhibits a high areal capacitance of 890 mF cm-2 and a remarkable specific capacitance of 1327 F g-1 at a current density of 5 mA cm-2. 93.36% of the initial capacitance was retained after 5000 cycles in 1 mol L-1 Na2SO4 indicating its high cycling stability. The synthesis route proves to be beneficial for a comprehensive yield of MnFe2O4@rGO nanosheets of different morphologies for use in the sophisticated design of energy-storing devices. This research strongly suggests that nanoparticle geometry, in addition to two-dimensional carbon-based materials, is a critical factor in a supercapacitor design.

2.
ACS Appl Bio Mater ; 3(4): 1924-1933, 2020 Apr 20.
Article in English | MEDLINE | ID: mdl-35025315

ABSTRACT

Bone fractures associated with osteoporosis are a major concern all over the world especially among the elderly population and postmenopausal women. Bisphosphonates (BPs) are widely used clinically for both treatment and prevention of osteoporosis despite their poor oral bioavailability and undesired side effects. Local delivery of BPs from polymeric scaffolds can improve the efficacy and overcome the undesirable side effects associated with oral bisphosphonate therapy. The aim of the present study is to explore the effectiveness of pamidronate (PDS) encapsulated electrospun polycaprolactone/polycaprolactone-polyethyleneglycol-polycaprolactone/nanohydroxyapatite (PCH) scaffolds in healing critical-size calvarial defects in an osteoporotic rat animal model. Prior to implantation studies, the effect of PDS on the fiber architecture, mechanical properties, and in vitro degradation behavior was evaluated. The in vitro release of PDS from PCH scaffolds in phosphate buffer saline (PBS) at 37 °C was monitored for a period of 21 days. An osteoporotic animal model was successfully developed in Wistar rats by bilateral ovariectomy. Results of micro CT (computed tomography) and blood serum analysis confirmed the osteoporotic model induction in rats. Critical-size calvarial defects of 8 mm size were created in osteoporotic rats, and the in vivo osteogenic efficacy of PCH-PDS scaffolds was evaluated by micro CT, histology, and histomorphometry. Micro CT analysis showed improved osseous tissue integration with the use of PDS-loaded PCH scaffolds after 12 week post implantation. Histology, density measurement using micro CT, and histomorphometry further substantiate that PCH-PDS scaffolds have the potential to be used for the repair of osteoporotic bone defects. Our findings revealed that incorporation of PDS onto PCH scaffolds provides a promising biomaterial that could be used for regenerating osteoporosis-related fractures.

3.
Nanoscale Adv ; 2(7): 2968-2976, 2020 Jul 14.
Article in English | MEDLINE | ID: mdl-36132389

ABSTRACT

Herein we report the development of novel multiferroic nanocomposites for their enhanced magnetic and electrical properties by employing a simple cost-effective chemical process at low temperatures. Novel perovskite-mixed spinel nanocomposites of (1 - x)BiFeO3/xMnFe2O4 where x = 0.1-0.5 have been prepared by a sol-gel auto-combustion technique. The calcination temperature was optimized and the phase formation of BiFeO3/MnFe2O4 nanocomposites was confirmed from the X-ray diffraction patterns for the samples calcined at 500 °C for 2 h. The grain sizes have been found to vary from 60 to 90 nm. The vibrational modes of the prepared nanocomposites were studied using Raman spectroscopy and FESEM and EDX were used to carry out the microstructural and composition analysis respectively. The magnetic properties seemed to have a strong dependence on the concentration of the spinel ferrite in the composite system. Saturation magnetization and coercivity exhibit an increase with increase in the MnFe2O4 content. The electrical properties from solid state impedance analysis confirm the non-Debye characteristics and the maximum activation energy is 0.931 eV for the 0.5BiFeO3/0.5MnFe2O4 nanocomposite. Dispersion in the dielectric constant and dielectric loss in the low frequency range has also been determined, which decreases with increase in temperature at lower ac frequencies.

4.
Indian J Dent Res ; 30(4): 630-633, 2019.
Article in English | MEDLINE | ID: mdl-31745064

ABSTRACT

Proliferative fasciitis is a pseudo-sarcomatous myofibroblastic proliferation characterized by the presence of unusual giant cells resembling ganglion cells, which usually occurs in the adult population with a mean age of 54 years. It usually affects the upper extremities and is rare in head and neck region with only 11 cases described in the literature so far. Because of rapid growth and histological similarity to various malignant tumors such as rhabdomyosarcoma, recognition of this benign condition is a matter of utmost importance when a pathologist is concerned. In this study, we report a case of a 11-year-old boy presented with a lesion on the right side of chin, along with a literature review involving those cases reported in the head and neck region.


Subject(s)
Chin , Fasciitis , Adult , Child , Diagnosis, Differential , Head , Humans , Male , Middle Aged , Neck
5.
Int J Biol Macromol ; 136: 266-274, 2019 Sep 01.
Article in English | MEDLINE | ID: mdl-31201909

ABSTRACT

Paclitaxel, an effective chemotherapeutic drug, is insoluble in aqueous solvents and is usually administered with excipients which have side effects. The use of this drug is also limited due to multi-drug resistance. In this study polysaccharide nanoparticles are used in the delivery of chemotherapeutic drug while minimizing side-effects, solubility issues and drug resistance. The use of biopolymers like galactoxyloglucan to synthesize nanoparticle makes it more biocompatible. This study involves the synthesis of PST-PTX nanoparticles using tamarind seed polysaccharide and Paclitaxel by epichlorohydrin crosslinking. The particles were further characterized by Dynamic Light Scattering (DLS), High-resolution transmission electron microscopy (HR-TEM) Fourier Transform Infrared Spectroscopy (FTIR) and UV-Visible spectroscopy. The cytotoxicity of PST-PTX nanoparticles in cancer cell lines and resistant cancer cell lines were determined by MTT assay. The quantitative analysis of cell death was determined by Annexin V dead cell assay, Caspase 3/7 assay and expression of pro-apoptotic protein Bax. The ability of the nanoparticle to overcome multi-drug resistance was evaluated by the expression of multidrug-resistant proteins P-glycoprotein (P-gp) and Breast cancer resistant protein (BCRP) in lung adenocarcinoma resistant cells (A549R). The present study provides evidence for the ability of PST-PTX nanoparticle to overcome multi-drug resistance and cause apoptotic cell death. The particle was found to be more effective than Paclitaxel in causing cell death in resistant cancer cells. Moreover, the particles were found to downregulate the expression of multi-drug resistant proteins P-gp and BCRP in resistant cell lines suggesting the ability of PST-PTX nanoparticles to overcome multi-drug resistance.


Subject(s)
Drug Resistance, Neoplasm/drug effects , Galactose/chemistry , Glucans/chemistry , Lung Neoplasms/pathology , Nanoparticles/chemistry , Paclitaxel/chemistry , Paclitaxel/pharmacology , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , ATP Binding Cassette Transporter, Subfamily G, Member 2/metabolism , Apoptosis/drug effects , Biological Transport , Caspase 3/metabolism , Caspase 7/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Down-Regulation/drug effects , Drug Carriers/chemistry , Humans , Lymphocytes/cytology , Lymphocytes/drug effects , Neoplasm Proteins/metabolism , Paclitaxel/metabolism
6.
Indian J Dent Res ; 29(2): 238-243, 2018.
Article in English | MEDLINE | ID: mdl-29652021

ABSTRACT

Ghost cell odontogenic carcinoma (GCOC) is a malignant odontogenic epithelial tumor which is an exceedingly rare, highly aggressive, rapidly growing, and infiltrative tumor forming the malignant counterpart of long-standing benign cystic lesions coming in the spectrum of calcifying odontogenic cysts. To date, only a few cases have been reported in the medical literature. A case of unusual presentation of GCOC is presented and the clinical, histopathological, and immunohistochemical features are discussed along with a literature review. Our case report further emphasizes the bizarre biological behavior of this tumor and the need for strict long-term surveillance of the patients as metastasis to distant sites has been reported.


Subject(s)
Mandibular Neoplasms/diagnosis , Odontogenic Tumors/diagnosis , Adult , Humans , Male , Mandibular Neoplasms/diagnostic imaging , Mandibular Neoplasms/pathology , Mandibular Neoplasms/surgery , Odontogenic Tumors/diagnostic imaging , Odontogenic Tumors/pathology , Odontogenic Tumors/surgery , Radiography, Panoramic , Tomography, X-Ray Computed
7.
J Biomater Sci Polym Ed ; 29(12): 1444-1462, 2018 08.
Article in English | MEDLINE | ID: mdl-29656699

ABSTRACT

In the present study, we attempt to modify Polycaprolactone (PCL) by blending it with a water soluble polymer Polyethyleneoxide (PEO) having two different molecular weights (Mv ~1,00,000 and 6,00,000) using electrospinning technique. The effect of PEO molecular weight and blend ratio on fiber morphology, porosity, surface wettability, static and dynamic mechanical properties of PCL was investigated. In vitro degradation studies in phosphate buffer saline (PBS) at 37 °C demonstrated formation of pores on fiber surface especially in blend scaffolds with 50:50 ratios. In vitro studies using human osteoblast sarcoma (hOS) cell lines on blend scaffolds showed improved cellular response with good cell adhesion, viability and proliferation. The study revealed that incorporation of PEO on PCL scaffolds complemented the properties of PCL and facilitated fabrication of scaffolds with improved hydrophilicity, mechanical property and tunable degradation profile with better cell viability which makes it an ideal candidate for bone tissue engineering applications.


Subject(s)
Bone and Bones/chemistry , Polyesters/chemistry , Polyethylene Glycols/chemistry , Tissue Scaffolds/chemistry , Absorbable Implants , Animals , Cell Adhesion , Cell Line , Cell Proliferation , Cell Survival , Cells, Cultured , Fibroblasts/cytology , Humans , Hydrophobic and Hydrophilic Interactions , Mechanical Phenomena , Mice , Osteoblasts/cytology , Osteogenesis , Porosity , Surface Properties , Tissue Engineering/methods
8.
Mater Sci Eng C Mater Biol Appl ; 77: 513-520, 2017 Aug 01.
Article in English | MEDLINE | ID: mdl-28532060

ABSTRACT

We have engineered hybrid polymer products based on a hybrid inorganic-organic comacromer consisting of hydroxyapatite (HA), carboxyl terminated polypropylene fumarate (CTPPF), PEG300 and ascorbic acid (AA) as a bone graft material. The integration and the spatial distribution of HA in the polymer backbone were facilitated by silanisation and 1-ethyl-3-(-3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) coupling technique. These comacromers and crosslinked polymer products were characterized by Fourier transform infrared spectroscopy (FTIR), Nuclear magnetic resonance (NMR), Scanning electron microscopy (SEM) and Raman mapping techniques. SEM and EDAX analysis substantiate high invitro bioactivity of the polymer products. SEM studies depict a distinct macroporous structure with pore size of 50 to 300µm. These crosslinked hybrid products demonstrated no significant difference in compressive moduli after 4weeks immersion in SBF. In particular, the compressive moduli were found to be comparable with that of trabecular bone. We suggest that the formation of an apatite layer on the surface of the composites deter initial degradation leading to better mechanical stability. As expected, the polymer products displayed negligible degradation in SBF during the first 4weeks which increased to a maximum of 25% by the end of the 8weeks time period. In addition these crosslinked products which are hydrophilic exhibit favorable albumin adsorption, cell viability, HOS cell adhesion and exemplary compatibility. Cumulatively, the results deduced in the present study suggest that these hybrid products have potential as a bone graft material.


Subject(s)
Biocompatible Materials/chemistry , Cell Adhesion , Durapatite , Microscopy, Electron, Scanning , Polymers , Spectroscopy, Fourier Transform Infrared
9.
Contemp Clin Dent ; 6(1): 69-73, 2015.
Article in English | MEDLINE | ID: mdl-25684915

ABSTRACT

BACKGROUND: Early childhood caries (ECC) is a severe form of dental decay with multi-factorial origin. OBJECTIVES: The aim of this cross-sectional study was to determine the prevalence and related risk factors of ECC among preschool children residing in rural and urban areas of Trivandrum district in Kerala. METHODS: A sample size of 1329 preschool children of <60 months of age was randomly selected from rural and urban areas of Trivandrum and decayed missing filled teeth indices were recorded. A standardized questionnaire was distributed to the parents. The data were subjected to SPSS version 16 and statistically analyzed with Chi-square test. RESULTS: Prevalence of ECC in the study sample was found to be 54%. Furthermore, a positive association was obtained between ECC and age of the child, location of residence, dietary habits, and oral hygiene habits. CONCLUSION: There is an urgent need to implement preventive and curative oral health programs for preschool children in rural and urban areas.

10.
J Environ Biol ; 35(6): 1137-44, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25522517

ABSTRACT

A detailed evaluation was performed on the soils of Nanmangalam Reserve Forest (NRF) in order to understand its physico-chemical, microbiological and enzymatic characteristics. The results of analysis showed that soil pH was directly proportional to the soil depth and the soil moisture content was irreversibly related to varying soil depth. Soil organic carbon was positively correlated with (p < 0.01) with total nitrogen, total bacterial count, cellulytic microbes, nitrogen-fixing bacteria, microbial biomass carbon, dehydrogenase activity and soil respiration. During summer, microbial population in the organic layer was more diverse than in the deepest layer. Analysis showed that NRF had low organic carbon content (less than 1%), microbial biomass, nutrient and functional microbes. The overall results of the analysis reinstate that Nanmangalam forest soil is undergoing degradation.


Subject(s)
Forests , Soil Microbiology , Soil/chemistry , Environmental Monitoring , India
11.
Indian J Physiol Pharmacol ; 58(3): 294-7, 2014.
Article in English | MEDLINE | ID: mdl-25906615

ABSTRACT

Obstructive sleep apnea (OSA) is a sleep related breathing disorder associated with high morbidity and mortality. Digit ratio (2D:4D) a sexually dimorphic trait is a putative indicator of prenatal testosterone exposure and adult testosterone level. Present study aimed at investigating the correlation between 2D:4D ratio and OSA based on the study conducted on 290 volunteered participants of both the sexes in the age range of 20-45 years. A significant negative correlation was observed for 2D:4D with OSA related parameters specifically Berlin score, Epworth score and certain key anthropometric measurements, neck circumference (NC) and waist-hip ratio (WHR). The study thus showed that lower 2D:4D ratio, increases risk of developing OSA and hence it can be used as an adjunct tool in the prediction of OSA.


Subject(s)
Fingers/anatomy & histology , Sleep Apnea, Obstructive/diagnosis , Adult , Female , Humans , Male , Middle Aged
12.
J Biomed Nanotechnol ; 9(9): 1483-94, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23980497

ABSTRACT

The present work is a comparative evaluation of physical and biological properties of electrospun biodegradable fibrous scaffolds based on polycaprolactone (PCL) and its blend with polycaprolactone-polyethyleneglycol-polycaprolactone (CEC) with and without nanohydroxyapatite (nHAP) particles. The fiber morphology, porosity, surface wettability, and mechanical properties of electrospun PCL were distinctly influenced by the presence of both copolymer CEC and nHAP. The degradation in hydrolytic media affected both morphological and mechanical properties of the scaffolds and the tensile strength decreased by 58% for PCL, 83% for PCL/CEC, 36% for PCL/nHAP and 75% for PCL/CEC/nHAP in 90 days of PBS ageing. MTT assay using mouse fibroblast L929 cells proved all the scaffolds to be non-cytotoxic. An overall enhanced performance was shown by PCL/CEC/nHAP scaffold in cell viability (LPH) and proliferation (Picogreen). Simultaneously, ELF assay of ALP activity (bone marker) confirmed the presence of osteogenic-induced Rabbit adipose-derived mesenchymal stem cells (ADMSCs) on all the scaffolds. In comparison, the results reveal the potential of the cytocompatible PCL/CEC/nHAP scaffold for the fabrication of living bony constructs for tissue engineering applications.


Subject(s)
Durapatite/chemistry , Ethylene Oxide/chemical synthesis , Lactones/chemical synthesis , Mesenchymal Stem Cells/cytology , Nanostructures/chemistry , Osteoblasts/cytology , Tissue Engineering/instrumentation , Tissue Scaffolds , Animals , Bone Development/physiology , Bone Substitutes/chemical synthesis , Cell Differentiation , Cells, Cultured , Equipment Design , Equipment Failure Analysis , Ethylene Oxide/therapeutic use , Lactones/therapeutic use , Materials Testing , Mesenchymal Stem Cells/physiology , Nanostructures/ultrastructure , Osteoblasts/physiology , Osteogenesis/physiology , Particle Size , Rabbits
13.
J Pharm Bioallied Sci ; 2(2): 141-3, 2010 Apr.
Article in English | MEDLINE | ID: mdl-21814449

ABSTRACT

Microsatellites known as simple-sequence repeats (SSRs) or short-tandem repeats (STRs), represent specific sequences of DNA consisting of tandemly repeated units of one to six nucleotides. The repetitive nature of microsatellites makes them particularly prone to grow or shrink in length and these changes can have both good and bad consequences for the organisms that possess them. They are responsible for various neurological diseases and hence the same cause is now utilized for the early detection of various diseases, such as, Schizophrenia and Bipolar Disorder, Congenital generalized Hypertrichosis, Asthma, and Bronchial Hyperresponsiveness. These agents are widely used for forensic identification and relatedness testing, and are predominant genetic markers in this area of application. The application of microsatellites is an extending web and covers the varied scenarios of science, such as, conservation biology, plant genetics, and population studies. At present, researches are progressing round the globe to extend the use of these genetic repeaters to unmask the hidden genetic secrets behind the creation of the world.

SELECTION OF CITATIONS
SEARCH DETAIL
...