A systematic review of differences in outcome between one and two stage palate repair in cleft lip and palate.

The aim of this systematic review was to determine whether one-stage palatoplasty for children born with cleft lip and palate shows overall advantages in outcome compared with two-stage palatoplasty. The included studies were controlled studies of syndromic and non-syndromic children born with unilateral cleft lip and palate, bilateral cleft lip and palate, or isolated cleft palate. The interventions studied were one-stage palatoplasty and two-stage palatoplasty starting with the soft palate. The outcomes were facial growth, speech, hearing, presence of fistulae, other complications related to surgery, health-related quality of life, and health economics. In total, 14 original studies were included. Results were dichotomized into showing advantage for one- or two-stage palatoplasty for the respective outcome and compared with the results from six included systematic reviews. No overall advantage for either surgical strategy was found for any of the outcome measures. The certainty of evidence was highest for the presence of fistulae, followed by facial growth and speech. For several outcomes, the quality of the existing evidence was too low to allow for any conclusions to be drawn. Neither one- nor two-stage palatoplasty showed significant advantages in clinical outcomes compared with the other. Other aspects such as ethics, economics, or surgeon's preference might hence be of more importance. Homogenous choices of outcome measures and defined minimal clinically important differences would facilitate further research.

Contrasting effects of nitrogen availability on plant carbon supply to mycorrhizal fungi and saprotrophs - a hypothesis based on field observations in boreal forest.

• Soil microorganisms are considered C-limited, while plant productivity is frequently N-limited. Large stores of organic C in boreal forest soils are attributed to negative effects of low temperature, soil acidity and plant residue recalcitrance upon microbial activity. • We examined microbial activity, biomass and community composition along a natural 90-m-long soil N supply gradient, where plant species composition varies profoundly, forest productivity three-fold and soil pH by three units. • There was, however, no significant variation in soil respiration in the field across the gradient. Neither did microbial biomass C determined by fumigation-extraction vary, while other estimates of activity and biomass showed a weak increase with increasing N supply and soil pH. Simultaneously, a phospholipid fatty acid attributed mainly to mycorrhizal fungi declined drastically, while bacterial biomass increased. • We hypothesize that low N supply and plant productivity, and hence low litter C supply to saprotrophs is associated with a high plant C supply to mycorrhizal fungi, while the reverse occurs under high N supply. This should mean that effects of N availability on C supply to these functional groups of microbes acts in opposing directions.

Nitrogen translocation between Alnus glutinosa (L.) Gaertn. seedlings inoculated with Frankia sp. and Pinus contorta Doug, ex Loud seedlings connected by a common ectomycorrhizal mycelium.

Uptake and translocation of nitrogen was studied in laboratory microcosms consisting of Alnus glutinosa (L.) Gaertn., Frankia sp., Paxillus involutus (Fr.) Fr. and Pinus contorta Dougl. ex Loud. P. involutus was shown to form a fully functional ectomycorrhizal association with alder as well as pine, and the seedlings thus became interconnected by a common mycelium. When microcosms were exposed to 15 N2 gas, interplant translocation of 15 N was observed in two out of three experiments. 15 N2 was fixed by Frankia and translocated to all other parts of the system. In the two experiments in which interplant translocation occurred, between 5 and 15% of the 15 N recovered was found in the pine seedlings. Within seven days, fixed N2 was incorporated into amino acids in the Frankia nodules, translocated to both the A. glutinosa and P. contorta seedlings and incorporated into macromolecules. In alder seedlings, citrulline and ornithine were the free amino acids that had both the highest 15 N enrichment levels and concentrations. In pine, glutamine and citrulline had the highest 15 N concentrations, and glutamine had the highest level of 15 N enrichment. 15 N enrichment levels were greatest in the nodules, at between 5.5 and 29% in the different amino acids and 12% in the macromolecular fraction. Enrichment levels decreased with increasing distance from the nodules. The uptake and translocation of 15 N applied as 15 NH4 Cl to the mycelium was also studied. 15 N was incorporated into amino acids in the mycelium and translocated further in this form. Generally, free amino acids had high 15 N enrichment levels in the mycelium, decreasing along the translocation pathway. Citrulline and glutamine were the amino acids with highest 15 N concentrations in all parts of the system. 15 N was also found in the macromolecular fraction.