Early Evidence for Northern Salmonid Fisheries Discovered using Novel Mineral Proxies.

Salmonid resources currently foster socioeconomic prosperity in several nations, yet their importance to many ancient circumpolar societies is poorly understood due to insufficient fish bone preservation at archaeological sites. As a result, there are serious gaps in our knowledge concerning the antiquity of northern salmonid fisheries and their impacts on shaping biodiversity, hunter-gatherer adaptations, and human-ecological networks. The interdisciplinary study presented here demonstrates that calcium-magnesium phosphate minerals formed in burned salmonid bones can preserve at ancient northern sites, thus informing on the early utilization of these resources despite the absence of morphologically classifiable bones. The minerals whitlockite and beta magnesium tricalcium phosphate were identified in rare morphologically classifiable Atlantic salmonid bones from three Mid-Holocene sites in Finland. Large amounts of beta magnesium tricalcium phosphate were also experimentally formed by burning modern Atlantic salmonid and brown trout bones. Our results demonstrate the value of these minerals as proxies for ancient northern salmonid fishing. Specifically, the whitlockite mineral was discovered in hearth sediments from the 5,600 year old Yli-Ii Kierikinkangas site on the Iijoki River in northern Finland. Our fine sieving and mineralogical analyses of these sediments, along with zooarchaeological identification of recovered bone fragments, have confirmed for the first time that the people living at this village did incorporate salmonids into their economies, thus providing new evidence for early estuary/riverine fisheries in northern Finland.

Outcome after coronary artery bypass surgery with miniaturized versus conventional cardiopulmonary bypass.

We have reviewed the results of our experience with the use of miniaturized (Mini-CPB) versus conventional (C-CPB) cardiopulmonary bypass in coronary artery bypass surgery (CABG). This study included 365 patients who underwent CABG with C-CPB and 101 patients with Mini-CPB. In-hospital mortality was lower in the C-CPB group (1.4% vs. 3.0%, P = 0.38). A better, but not statistically significant, immediate outcome was observed in the C-CPB group as indicated by a shorter length of stay in the intensive care unit as well as a lower incidence of combined adverse end-point. However, this was probably due to significantly higher operative risk in the Mini-CPB group (logistic EuroSCORE: 8.5 +/- 10.0 vs. 4.6 +/- 7.1, P < 0.0001). Seventy-seven propensity score-matched pairs had similar immediate postoperative results after Mini-CPB and C-CPB (30-day mortality: 1.3% vs. 1.3%; stroke: 0% vs. 0%; intensive care unit stay > or = 5 days: 6.5% vs. 9.1%; combined adverse events: 14.3% vs. 11.7%). Mini-CPB achieves similar results to C-CPB in patients undergoing isolated CABG. The potential efficacy of Mini-CPB is expected to be more evident in high-risk patients or in complex cardiac surgery requiring much longer cardiopulmonary perfusion.

Different effects of pH on the permeation of pilocarpine and pilocarpine prodrugs across the isolated rabbit cornea.

Ocular absorption of pilocarpine and many other ophthalmic drugs can be improved by prodrug derivatization. For stability and solubility reasons basic prodrugs must be formulated at acidic pH, which may affect the corneal drug permeability. We studied the effects of pH on in vitro permeation of pilocarpine, pilocarpic acid benzyl diester prodrugs [O-propionyl (I) and O-valeryl (II)] and O,O'-(1, 4-xylylene) bispilocarpic acid diester prodrugs [O,O'-diacetyl (III), O,O'-dipropionyl (IV) and O,O'-divaleryl (V)] through albino rabbit cornea. Reversed-phase high-performance liquid chromatography was used to assay pilocarpine and its prodrugs. The permeability coefficient for pilocarpine decreased more than three times, from 2. 8x10-6 cm/s to 0.9x10-6 cm/s, when the pH was decreased from 7.65 to 5.5. At pH 7.65 permeability of pilocarpine improved several fold with delivery as prodrugs. Acidic pH (5.5, 6.0) affected to a different extent the corneal permeability of pilocarpine given as prodrugs. Consequently, the rank order of the corneal permeabilities among the compounds was different at various pH values. The effect of pH was greatest (an order of magnitude) for prodrugs with intermediate lipophilicity (I, III, IV), while pH had only minor or no effect on permeability of the most lipophilic prodrugs (II, V). In conclusion, the effect of pH on pilocarpine delivery as prodrug is dependent on prodrug structure and the advantage gained with prodrugs relative to pilocarpine is dependent on formulation pH.

Is Daphnia magna an ecologically representative zooplankton species in toxicity tests?

Daphnia magna is commonly used in aquatic toxicity testing because of many characters that make it easy and economical to culture in the laboratory: it is relatively small, has short life cycle, high fecundity, and parthenogenetic reproduction. On the other hand, D. magna differs from other freshwater zooplankters in size, habitat, life-history, and ability to withstand fish predation. D. magna is a relatively large zooplankton species which makes it so vulnerable to fish predation that it is excluded from fish-inhabiting lakes. It occurs mainly in ephemeral habitats like small ponds and rockpools where vertebrate predators are rare. As a result, D. magna is seldom an indigenous species in lakes which receive pollutants, although representativeness is one important criterion for the standardised toxicity test species. Small ponds are unpredictable habitats with large temporal and spatial variability in abiotic factors. Adaptation to this natural abiotic stress may increase pollution tolerance. The life-history of D. magna also differs from that of lake-inhabiting cladocerans. Large daphnids produce many small neonates, whereas the opposite is true for small cladocerans. The large neonate size allows an earlier maturation of small cladocerans compared to daphnids. In a few comparative studies D. magna tended to be less sensitive to toxic substances than other cladocerans, and this may be due in part to life-history and size differences.