Postoperative Acute Submandibular Sialadenitis: A Case Report.

Acute postoperative sialadenitis is a rare complication usually after surgery involving extreme head and neck rotation, such as posterior fossa surgery. It is characterized by the development of swelling in the submandibular region, usually contralateral to the surgical side, either immediately or within hours post-operatively. We report a case of a 43-year-old woman who developed sialadenitis leading to upper airway obstruction in the postoperative period. Further, she developed bilateral neck and face swelling. Dexmedetomidine used as an infusion throughout the surgery could be an additional cause. Swelling without signs of inflammation is rapidly progressive and may cause airway obstruction. Therefore, awareness and recognition are important, as a delay in airway securement can cause a complete collapse of the airway. Keywords: airway obstruction; case reports; sialadenitis.

Functional evolution of C(4) pyruvate, orthophosphate dikinase.

Pyruvate,orthophosphate dikinase (PPDK) plays a controlling role in the PEP-regeneration phase of the C(4) photosynthetic pathway. Earlier studies have fully documented its biochemical properties and its post-translational regulation by the PPDK regulatory protein (PDRP). However, the question of its evolution into the C(4) pathway has, until recently, received little attention. One assumption concerning this evolution is that changes in catalytic and regulatory properties of PPDK were necessary for the enzyme to fulfil its role in the C(4) pathway. In this study, the functional evolution of PPDK from its ancient origins in the Archaea to its ascension as a photosynthetic enzyme in modern C(4) angiosperms is reviewed. This analysis is accompanied by a comparative investigation into key catalytic and regulatory properties of a C(3) PPDK isoform from Arabidopsis and the C(4) PPDK isoform from Zea mays. From these analyses, it is proposed that PPDK first became functionally seated in C(3) plants as an ancillary glycolytic enzyme and that its transition into a C(4) pathway enzyme involved only minor changes in enzyme properties per se.