Prediction Equations for Spirometry in Adults from Northern India.

Background. Most of the Indian studies on prediction equations for spirometry in adults are several decades old and may have lost their utility as these were carried out with equipment and standardisation protocols that have since changed. Their validity is further questionable as the lung health of the population is likely to have changed over time. Objective. To develop prediction equations for spirometry in adults of north Indian origin using the 2005 American Thoracic Society/European Respiratory Society (ATS/ERS) recommendations on standardisation. Methods. Normal healthy non-smoker subjects, both males and females, aged 18 years and above underwent spirometry using a non-heated Fleisch Pneumotach spirometer calibrated daily. The dataset was randomly divided into training (70%) and test (30%) sets and the former was used to develop the equations. These were validated on the test data set. Prediction equations were developed separately for males and females for forced vital capacity (FVC), forced expiratory volume in first second (FEV1), FEV1/FVC ratio, and instantaneous expiratory flow rates using multiple linear regression procedure with different transformations of dependent and/or independent variables to achieve the best-fitting models for the data. The equations were compared with the previous ones developed in the same population in the 1960s. Results. In all, 685 (489 males, 196 females) subjects performed spirometry that was technically acceptable and repeatable. All the spirometry parameters were significantly higher among males except the FEV1/FVC ratio that was significantly higher in females. Overall, age had a negative relationship with the spirometry parameters while height was positively correlated with each, except for the FEV1/FVC ratio that was related only to age. Weight was included in the models for FVC, forced expiratory flow (FEF75) and FEV1/FVC ratio in males, but its contribution was very small. Standard errors of estimate were provided to enable calculation of the lower limits of normal and standardised residuals for these parameters. The equations were found to be valid on the test dataset, and therefore, may be extended to general population. Comparison with the 1960s equations revealed lack of good agreement, and substantially higher predicted FVC with the current equations, especially in the forty-years-plus age group, in both males and females. Even in the age group upto 40 years, the level of agreement was clinically not acceptable. Conclusions. Validated prediction equations have been developed for spirometry variables in adults of north Indian origin using the current ATS/ERS spirometry standardisation recommendations. The equations suggest an improvement in the lung health of the population over time in the middle-aged and the elderly. These equations should address a long-felt unmet need and enable a more appropriate evaluation of spirometry data in different chest diseases in Indian subjects.

Bilateral Tinea Nigra of palm: A rare case report from Eastern India.

A 14 year old girl from a coastal district of Odisha presented with a six month history of asymptomatic brownish patches on the palm of the both hands. Epidermal scrape from these patches showed brown septate hyphae with occasional yeast like cells. Hortaea wernekii was isolated from the fungal culture. A diagnosis of Tinea nigra was made. The patches resolved completely after treatment with topical 1% clotrimazole cream.

Physical microenvironment of platelet membrane in acute myocardial infarction.

Patients with acute myocardial infarction have more reactive platelets than those from normal population. These pathological platelets had more viscous plasma membrane, as inferred from fluorescence polarisation studies, and a lower fusion activation energy (delta E) of the membrane, reflecting a higher degree of order within lipid-lipid interactions.

Do ribosomal RNAs act merely as scaffold for ribosomal proteins.

Investigations that are being carried out in various laboratories including ours clearly provide the answer which is in the negative. Only the direct evidences obtained in this laboratory will be presented and discussed. It has been unequivocally shown that the interaction between 16S and 23S RNAs plays the primary role in the association of ribosomal subunits. Further, 23S RNA is responsible for the binding of 5S RNA to 16S.23S RNA complex with the help of three ribosomal proteins, L5, L18, L15/L25. The 16S.23S RNA complex is also capable of carrying out the following ribosomal functions, although to small but significant extents, with the help of a very limited number of ribosomal proteins and the factors involved in protein synthesis: (a) poly U-binding, (b) poly U-dependent binding of phenylalanyl tRNA, (c) EF-G-dependent GTPase activity, (d) initiation complex formation, (e) peptidyl transferase activity (puromycin reaction) and (f) polyphenylalanine synthesis. These results clearly indicate the direct involvement of rRNAs in the various steps of protein synthesis. Very recently it has been demonstrated that the conformational change of 23S RNA is responsible for the translocation of peptidyl tRNA from the aminoacyl (A) site to the peptidyl (Ρ) site. A model has been proposed for translocation on the basis of direct experimental evidences. The new concept that ribosomal RNAs are the functional components in ribosomes and proteins act as control switches may eventually turn out to be noncontroversial.