Variety of Plant Oils: Species-Specific Lipid Biosynthesis.

Plant oils represent a large group of neutral lipids with important applications in food, feed and oleochemical industries. Most plants accumulate oils in the form of triacylglycerol within seeds and their surrounding tissues, which is comprised of three fatty acids attached to a glycerol backbone. Different plant species accumulate unique fatty acids in their oils, serving a range of applications in pharmaceuticals and oleochemicals. To enable the production of these distinctive oils, select plant species have evolved specialized oil metabolism pathways, involving differential gene co-expression networks and structurally divergent enzymes/proteins. Here, we summarize some of the recent advances in our understanding of oil biosynthesis in plants. We compare expression patterns of oil metabolism genes from representative species, including Arabidopsis thaliana, Ricinus communis (castor bean), Linum usitatissimum L. (flax), and Elaeis guineensis (oil palm) to showcase the co-expression networks of relevant genes for acyl metabolism. We also review several divergent enzymes/proteins associated with key catalytic steps of unique oil accumulation, including fatty acid desaturases, diacylglycerol acyltransferases, and oleosins, highlighting their structural features and preference towards unique lipid substrates. Lastly, we briefly discuss protein interactomes and substrate channeling for oil biosynthesis and the complex regulation of these processes.

[Congenital laryngeal stridor - an interdisciplinary problem]. / Wrodzony stridor krtaniowy­ problem interdyscyplinarny.

UNLABELLED: The most common causes of laryngeal stridor are laryngomalacia (60%), vocal cord paralysis (VCP) (10 %) and subglottic laryngeal stenosis. Majority of cases of VCP are idiopathic, less frequently it is the effect of abnormalities in central nervous system (Arnold - Chiari syndrome, hydrocephalus, neonatal hypoxia). Differential diagnosis should also include anomalies of aortic arch and its branches (vascular rings). The authors present two cases of neonatal congenital laryngeal stridor. In the first case the girl presented with VCP of unknown etiology. The perinatal period was normal, ultrasound of central nervous system and neurologic examination revealed no abnormalities. Due to sustained VCP in control laryngeal ultrasound examinations, tracheostomy was performed in the third month of life. In the second case, stridor was caused by laryngomalacia and subglottic laryngeal stenosis of first grade according to Meyer-Cotton scale (larynx lumen diameter <4 mm). The diagnosis was established by laryngotracheobronchoscopy. In both children angiotomography was performed and vascular ring was diagnosed (aberrant right subclavian artery). Vascular anomaly was suspected in barium X-ray. In both cases echocardiographic examination did not visualize the fourth vessel of the aortic arch. Chest X- rays were normal. Both children had no symptoms caused by vascular ring. CONCLUSION: Diagnosis of congenital laryngeal stridor is an indication for complete evaluation to establish the cause of the airway obstruction. The differential diagnosis should include laryngomalacia, vocal cord paralysis, subglottic laryngeal stenosis, congenital anomalies of large vessels and abnormalities of the central nervous system.