Idiopathic leukoplakia- report of a rare case and review.

Idiopathic leukoplakia is a rare potentially malignant lesion, usually found on the tongue with an increased risk of malignant transformation as compared to the tobacco associated form. The risk of malignant transformation increases with age. Diagnosis poses a challenge to the clinician as it is diagnosed by exclusion of other possible causes leading to hyperkeratosis. We present one such rare case in an elderly male patient who was followed up for a year to record the course of the lesion and to report recurrences, if any.

Energy transfer based emission analysis of (Tb³âº, Sm³âº): lithium zinc phosphate glasses.

The present paper reports on the results pertaining to photoluminescence properties of Tb(3+), Sm(3+) and energy transfer from Tb(3+) to Sm(3+) ions in lithium zinc phosphate (LZP) glass matrix prepared by melt quenching method. Besides photoluminescence studies thermal stability for the LZP glass is also evaluated from TG-DTA measurement. Tb(3+) doped glasses have exhibited a prominent green emission at 547 nm assigned to (5)D4→(7)F5 transitions on exciting at λ(exci)=377 nm. The quenching phenomenon in Tb(3+) emission on varying its concentration has been discussed from cross-relaxations. Sm(3+) incorporated glasses have shown strong orange emission at 603 nm assigned to (4)G5/2→(6)H7/2 transition upon exciting with λ(exci)=404 nm. The possibility of energy transfer process taking place between these two ions is understood from the significant spectral overlap of Sm(3+) absorption and Tb(3+) emission. Migration of excitation energy from Tb(3+) ions to Sm(3+) ions at λ(exci)=375 nm is evaluated from the emission spectra of (0.5 mol.% Tb(3+)+(0.5-2.0 mol.%) Sm(3+)) co-doped glasses. The emission intensity of Sm(3+) has enhanced while Tb(3+) emission intensity decreased with an increase in Sm(3+) concentration suggesting the occurrence of energy transfer through cross-relaxations from Tb(3+) ((5)D4) to Sm(3+) ((4)G5/2). The mechanism behind energy transfer process has been further explained from energy level diagram, decay profiles and confirmed by calculating energy transfer parameters (energy transfer efficiency (η) and energy transfer probability (P)) of co-doped glasses. The dipole-dipole interaction is found to be more responsible for energy transfer Tb(3+) ((5)D4) to Sm(3+) ((4)G5/2) ions in LZP glass matrix.

Off-pump coronary artery bypass in congenital absence of pericardium.

Off-pump coronary artery bypass involves precise manipulations for proper positioning the heart without causing hemodynamic compromise. Pericardial stay sutures exerting appropriate traction play an important role in off-pump surgery. We report a rare case in which a congenital pericardial defect was discovered after sternotomy in a patient undergoing off-pump coronary artery bypass.