Relation between Nasal Septal Deviation and Pneumatization of Mastoid Air Cells – A Computerised Tomographic Study

Introduction: The environment of middle ear cavity gets regulated mostly by pneumatized mastoid air cell system (MACS). Many theories exist that details the process of pneumatization of this MACS. The nasal septal deviation (NSD) has been shown to be instrumental in influencing pneumatization of paranasal sinuses to varied degrees. The effect of NSD on the pneumatization of MACS remains questionable due to limited literature available. And so this study was done to find the relation between the side of NSD and extent of Pneumatization of MACS on that side by computerized tomographs of Paranasal sinus region. Subjects and Methods: 120 CT images of paranasal region from archives of radiology department were studied for NSD. The NSD was classified according to the nasal septal angle. The extent of pneumatization of mastoid region was studied and classified. The relation between severe NSD and extent of mastoid pneumatization was noted. Results: NSD was found to be right sided in 90% cases studied and 20, 45, 55 were seen belonging to group I, II and III NSD respectively. The mean NSA was found to be 13.5o. Mastoid region was observed to be hypo pneumatized in the side of NSD in 42 cases of group III NSD. Conclusion: The findings of the study puts forth the need for assessment of NSD and planning possible correction of NSD prior to middle ear and mastoid surgeries for successful results.

Effect of cigarette smoking on muscle strength of flexibility of athletes.

Kraus-Webber test which indicates muscle strength and flexibility of certain group of muscles showed significant decrease in cigarette smoking athletes in the age group of 19-30 years compared to nonsmoking athletes. The results indicate tobacco smoke inhalation affects muscle flexibility and strength required for athletes.

Recognition schemes for protein-nucleic acid interactions.

The molecular forces involved in protein-nucleic acid interaction are electrostatic, stacking and hydrogen-bonding. These interactions have a certain amount of specificity due to the directional nature of such interactions and the spatial contributions of the steric effects of different substituent groups. Quantum chemical calculations on these interactions have been reported which clearly bring out such features. While the binding energies for electrostatic interactions are an order of magnitude higher, the differences in interaction energies for structures stabilised by hydrogen-bonding and stacking are relatively small. Thus, the molecular interactions alone cannot explain the highly specific nature of binding observed in certain segments of proteins and nucleic acids. It is therefore logical to assume that the sequence dependent three dimensional structures of these molecules help to place the functional groups in the correct geometry for a favourable interaction between the two molecules. We have carried out 2D-FT nuclear magnetic resonance studies on the oligonucleotide d- GGATCCGGATCC. This oligonucleotide sequence has two binding sites for the restriction enzyme Bam H1. Our studies indicate that the conformation of this DNA fragment is predominantly B-type except near the binding sites where the ribose ring prefers a 3E conformation. This interesting finding raises the general question about the presence of specificity in the inherent backbone structures of proteins and nucleic acids as opposed to specific intermolecular interactions which may induce conformational changes to facilitate such binding.