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Background: Proper position of the head and the neck is important for optimizing laryngoscopic view and for ease of endotracheal intubation.We compared two different positions, sniffing position and simple head extension during direct laryngoscopy on the basis of laryngoscopic view, intubation difficulty and sympathetic response. Methodology: One hundred twenty patients of age group 20-50 years, scheduled for elective surgeries under general anaesthesia were divided into two equal groups in a randomized fashion. In group A (n = 60), sniffing position during laryngoscopy and intubation; and in group B(n =60),simple head extension position during laryngoscopy and intubation. Laryngoscopy view, ease of intubation and hemodynamic parameters were recorded. Results: Demographic data and the different parameters for assessment of difficult airway were similar in both groups. Glottic visualization grade was superior in group A and intubation difficulty score were higher in Group B (P < 0.05), Hemodynamic parameters at different time intervals were comparable. Conclusion: Sniffing position during laryngoscopy was found to be superior to simple head extention position in respect of better glottis visualization and ease of intubation though no difference in sympathetic response to intubation was found.

Cyclin-dependent kinases (Cdks) control the eukaryotic cell cycle by phosphorylating serine and threonine residues in key regulatory proteins, but some Cdk family members may exert kinase-independent functions that cannot easily be assessed using gene knockout approaches. While Cdk2-deficient mice display near-normal mitotic cell proliferation due to the compensatory activities of Cdk1 and Cdk4, they are unable to undergo meiotic generation of gametes and are consequently sterile. To investigate whether Cdk2 regulates meiosis via protein phosphorylation or by alternative kinase-independent mechanisms, we generated two different knockin mouse strains in which Cdk2 point mutations ablated enzyme activity without altering protein expression levels. Mice homozygous for the mutations Cdk2(D145N/D145N) or Cdk2(T160A/T160A) expressed only 'kinase-dead' variants of Cdk2 under the control of the endogenous promoter, and despite exhibiting normal expression of cell cycle regulatory proteins and complexes, both mutations rendered mice sterile. Mouse cells that expressed only 'kinase-dead' variants of Cdk2 displayed normal mitotic cell cycle progression and proliferation both in vitro and in vivo, indicating that loss of Cdk2 kinase activity exerted little effect on this mode of cell division. In contrast, the reproductive organs of Cdk2 mutant mice exhibited abnormal morphology and impaired function associated with defective meiotic cell division and inability to produce gametes. Cdk2 mutant animals were therefore comparable to gene knockout mice, which completely lack the Cdk2 protein. Together, our data indicate that the essential meiotic functions of Cdk2 depend on its kinase activity, without which the generation of haploid cells is disrupted, resulting in sterility of otherwise healthy animals., info:eu-repo/semantics/published