N. L. Misra

Synthesis of oleic acid functionalized Fe3O4 magnetic nanoparticles and studying their interaction with tumor cells for potential hyperthermia applications.

In the present study, oleic acid (OA) functionalized Fe3O4 magnetic nanoparticles (MN) were synthesized following modified wet method of MN synthesis. The optimum amount of OA required for capping of MN and the amount of bound and unbound/free OA was determined by thermogravimetric analysis (TGA). Further, we have studied the effect of water molecules, associated with MN, on the variation in their induction heating ability under alternating current (AC) magnetic field conditions. We have employed a new approach to achieve dispersion of OA functionalized MN (MN-OA) in aqueous medium using sodium carbonate, which improves their biological applicability. Interactions amongst MN, OA and sodium carbonate were studied by Fourier transform infrared spectroscopy (FT-IR). Intracellular localization of MN-OA was studied in mouse fibrosarcoma cells (WEHI-164) by prussian blue staining and confocal laser scanning microscopy (CLSM) using nile blue A as a fluorescent probe. Results showed MN-OA to be interacting mainly with the cell membrane. Their hyperthermic killing ability was evaluated in WEHI-164 cells by trypan blue method. Cells treated with MN-OA in combination with induction heating showed decreased viability as compared to respective induction heating controls. These results were supported by altered cellular morphology after treatment of MN-OA in combination with induction heating. Further, the magnitude of apoptosis was found to be ~5 folds higher in cells treated with MN-OA in combination with induction heating as compared to untreated control. These results suggest the efficacy of MN-OA in killing of tumor cells by cellular hyperthermia.

Luminescence, lifetime, and quantum yield studies of redispersible Eu3+-doped GdPO4 crystalline nanoneedles: Core-shell and concentration effects

Crystalline nanoneedles of Eu3+-doped GdPO4 and Eu3+-doped GdPO4 covered with GdPO4 shell (core shell) have been prepared at relatively low temperature of 150 °C in ethylene glycol medium. From luminescence study, asymmetric ratio of Eu3+ emission at 612 nm (electric dipole transition) to 592 nm (magnetic dipole transition) is found to be less than one. Maximum luminescence was observed from the nanoparticles with Eu3+ concentration of 5 at. %. For a fixed concentration of Eu3+ doping, there is an improvement in emission intensity for core-shell nanoparticles compared to that for core. This has been attributed to effective removal of surface inhomogeneities around Eu3+ ions present on the surface of core as well as the passivation of inevitable surface states, defects or capping ligand (ethylene glycol) of core nanoparticles by bonding to the shell. Lifetime for D50 level of Eu3+ was found to increase three times for core-shell nanoparticles compared to that for core confirming the more Eu3+ ions with sym...

Efficacy of diode laser in the management of oral lichen planus

Oral lichen planus (OLP) is a common chronic disease of uncertain aetiology. Treatment of patients with symptomatic OLP represents a therapeutic challenge. Despite numerous existing remedies, there are many treatment failures. The diode laser therapy is used as a possible alternative method in the treatment of lichen planus. The patient with OLP lesions was treated using diode laser (940 nm) for the symptomatic relief of pain and burning sensation. The patient was assessed before, during and after the completion of the treatment weekly. The treatment was performed for 2 months and the patient showed complete remission of burning sensation and pain (visual analog scale 0%). The follow-up was performed for 7 months and no recurrence of burning sensation was found. Diode laser therapy seems to be an effective alternative treatment for relieving the symptoms of OLP.

Angina bullosa haemorrhagica.

Angina bullosa haemorrhagica is the term used to describe benign subepithelial oral mucosal blisters filled with blood that are not attributable to a systemic disorder or haemostatic defect. It is a very rare condition. Elderly patients are usually affected and lesions heal spontaneously without scarring. The pathogenesis is unknown, although it may be a multifactorial phenomenon. Trauma seems to be the major provoking factor and long-term use of steroid inhalers has also been implicated in the disease. We present a 50-year-old patient with angina bullosa haemorrhagica. Trauma by sharp cusp of adjacent tooth and metal crown were identified as aetiological factors in this case. Lesions healed after removal of the metal crown and rounding of the cusp. Therefore, recognition of the lesion is of great importance to dentists, to avoid misdiagnosis.

940 nm diode laser therapy in management of recurrent apthous ulcer

Recurrent apthous stomatitis (RAS) is one of the most common oral inflammatory diseases characterised by painful recurrent ulcerations of the orofacial region. The ulcers occur in three clinical forms: minor, major and herpetiform. Several therapies have been advocated to manage these lesions such as topical corticosteroids (triamcinolone acetonide, hydrocortisone acetate and clobetasol propionate), chlorhexidine mouth rinses, tetracycline oral rinses, thalidomide, fluocinonide, colchicines and the immune boosting agent levamosile, vitamin therapy and topical interferon α-2a. Laser therapy is used as an alternative method in treatment of RAS. In this paper one patient with RAS was treated using a 940 nm diode laser for symptomatic relief of pain and burning sensation and healing of ulcer.

Direct Determination of Oxidation States of Uranium in Mixed-Valent Uranium Oxides Using Total Reflection X-ray Fluorescence X-ray Absorption Near-Edge Spectroscopy

Total reflection X-ray fluorescence (TXRF)-based X-ray absorption near-edge spectroscopy has been used to determine the oxidation state of uranium in mixed-valent U3O8 and U3O7 uranium oxides. The TXRF spectra of the compounds were measured using variable X-ray energies in the vicinity of the U L3 edge in the TXRF excitation mode at the microfocus beamline of the Indus-2 synchrotron facility. The TXRF-based X-ray absorption near-edge spectroscopy (TXRF-XANES) spectra were deduced from the emission spectra measured using the energies below and above the U L3 edge in the XANES region. The data processing using TXRF-XANES spectra of U(IV), U(V), and U(VI) standard compounds revealed that U present in U3O8 is a mixture of U(V) and U(VI), whereas U in U3O7 is mixture of U(IV) and U(VI). The results obtained in this study are similar to that reported in literature using the U M edge. The present study has demonstrated the possibility of application of TXRF for the oxidation state determination and elemental speciation of radioactive substances in a nondestructive manner with very small amount of sample requirement.

Oxygen vacancy induced magnetism in (Th0.9Bi0.1)O1.95 solid solution

We present a magnetic study on Bi doped ThO2. EPR study revealed a clear signature of oxygen vacancies as a result of doping Bi. Interestingly, we also observe clear indication of a ferromagnetic behavior in the Bi doped ThO2. FC and ZFC measurements clearly indicate the ferromagnetic ordering at low temperature. The magnetism presumably originates from the oxygen vacancies created by doping lower valent cations into ThO2.

Osteoma of temporomandibular joint: a rarity

Osteoma is a benign tumour consisting of mature bone tissue. It is an uncommon lesion that occurs in the bones of the craniofacial complex. Only a few cases involving the temporomandibular joint have been reported. An osteoma of the left temporomandibular joint causing limited mouth opening in a 22-year-old man with CT findings revealing the unusual possibility in differential diagnosis of trismus.

Nasopalatine canal cyst: often missed

Nasopalatine canal cyst may occur within the nasopalatine canal or in the soft tissues of the palate, at the opening of the canal, where it is called the ‘cyst of the palatine papilla’. These are normally asymptomatic, constituting casual radiological findings. We present a case report of a male patient with infected nasopalatine canal cyst seen clinically as swelling over palate. Radiographic interpretation should be thoroughly performed for maxillary anterior region and any occlusal radiograph in routine radiography to screen this entity and must be distinguished from other maxillary anterior radiolucencies by the clinician.

Dental age estimation by Demirjian's and Nolla's method: A comparative study among children attending a dental college in Lucknow (UP)

Introduction: Estimation of age is an important aspect of forensic science. The assessment of age is useful in forensic odontology and in treatments plans of orthodontic and pedodontic patients. Aims and Objectives: The aim of the study was to determine dental age from orthopantomograph using Demirjians method and Nollas method. It was also to evaluate the interrelationship between chronological and dental age according to both these methods and to evaluate which technique was better. Materials and Methods: The study was conducted in the Department of Oral Medicine and Radiology of Babu Banarasi Das College of Dental Sciences (UP, Northern India). A total of 300 subjects (150 girls and 150 boys) of age group from 6 years to 15 years were enrolled. These subjects were grouped by a difference of 1 year into 10 groups (each group comprised of 30 subjects: 15 males and 15 females). For every individual included in the study a panoramic radiograph was taken, with standard parameters and adequate protective measures. Results: The results imply that Demirjians method is applicable to all age groups and for both genders with better accuracy than Nollas method, which had a limited utility in younger age group. Thus Demirjians method is a better method when compared to Nollas method in Northern Indian population.