Lymphatic transport in rats of interesterified oils containing conjugated linoleic acids

In this study we examined the lymphatic transport in rats of FA after administration of interesterified oils containing CLA, with emphasis on the location of CLA and octanoic acid in the TAG. The oils were produced by enzymatic interesterification. Eight oils with different structures or FA profiles were examined in this study: MCM, CMC, OCO, and COC, where M was expected to be octanoic acid and O oleic acid. In group 1, C was CLA as a mixture of the two CLA isomers c9, t11 or t10, c12, and in group 2, C was mainly the isomer t10, c12. Rats were subjected to cannulation of the mesenteric lymph duct, and the following day they were intragastrically administered one of the oils and lymph samples were collected for 24 h. The lymphatic transport of total FA from 0 to 8 h in group 1 was significantly (P < 0.05) higher for the OCO-1 and the COC-1 oils than for the CMC-1 oil. Similarly, in group 2 the transport was higher for the OCO-2 oil than for the CMC-2 oil. The recovery of both of the CLA isomers examined was similar (50-70%) and independent of the isomer, oil structure, and FA profile, whereas more octanoic acid was recovered from the CMC oils than from the MCM oils. The results indicated that the FA profiles and the position of octanoic acid had only a minor influence on the absorption of CLA.     

Anionic Clays as Potential Slow-Release Fertilizers: Nitrate Ion Exchange

Several nitrate containing anionic clays were synthesized at different temperatures and the kinetics of NO₃ ^– release were determined to test their suitability as slow-release N fertilizers. A sample (Mg:Al = 2:1) synthesized at 60°C with smaller particle size released 75, 86 and 100% of its NO₃ ^– in 1, 3 and 7 days, respectively when equilibrated with a simulated soil solution. On the other hand, the 175°C/2 hrs sample with larger particle size released 65, 77 and 84% of its nitrate in 1, 3 and 7 days, respectively. Another anionic clay (synthesized at 175°C/24 hrs) of higher charge density (Mg:Al = 2:1) containing NO₃ ^– was equilibrated with a 0.012 N NaCl or Na₂CO₃ to test the role of different anions in releasing the NO₃ ^– anion from the interlayers. The results showed that Cl^– released more NO₃ ^– than did CO₃ ^2– from this anionic clay after all the treatment times probably as a result of the CO₃ ^2– anion blocking the release of NO₃ ^– from the interior of the crystals. When a lower charge density (Mg:Al = 3:1) sample (synthesized at 175°C/48 hrs) was equilibrated with 0.02N solution of anions the release of nitrate was as follows: Cl^– < F^– < SO₄ ⁼ CO₃ ^2–. These results suggest that the divalent SO₄ ⁼ and CO₃ ^2– anions are more effective in the release of NO₃ ^– from this lower charge density anionic clay. Time-resolved structural analysis of NO₃ ^– exchange with CO₃ ^2– in the above anionic clay using synchrotron x-ray diffraction showed that ion exchange is rapid because of small crystal size and lower charge density. Thus the release of NO₃ ^– from anionic clays is an interplay among the type of anions present in soil solution, their concentration, pH of soil solution, the charge density and crystal size of anionic clay etc.     

Mutation of herpesvirus thymidine kinase to generate ganciclovir-specific kinases for use in cancer gene therapies

Understanding the functional and mechanistic properties of themulti-substrate herpes simplex virus type-1 thymidine kinase(HSV-1 TK) remains critical to defining its role as a majorpharmacological target in herpesvirus and gene therapies forcancer. An inherent limitation of the activity of HSV-TK isthe >70-fold difference in the K_ms for phosphorylation ofthymidine over the pro-drug ganciclovir (GCV). To engineer anHSV-1 TK isoform that is specific for GCV as the preferred substrate,16 site-specific mutants were generated. The mutations wereconcentrated at conserved residues involved in nucleoside basebinding, Gln125 and near sites 3 and 4 involved in catalysisand substrate binding. The substrate preferences of each mutantenzyme were compared with wild-type HSV-1 TK. One mutant, termedQ7530 TK, had a lower K_m for GCV than thymidine. Expressionof the Q7530 TK in tumor cells indicated comparable metabolismto and improved sensitivity to GCV over wild-type HSV-1 TK,with minimal thymidine phosphorylation activity. A molecularmodeling simulation of the different HSV-1 TK active-sites wasdone for GCV and thymidine binding. It was concluded that mutationsat Gln125 and near site 4, especially at Ala168, were responsiblefor loss of deoxypyrimidine substrate binding.     

Size distribution functions of dispersions

The size distribution function of bubbles in thermodynamic equilibrium with the surrounding liquid has been derived in the absence of gravity. The derivation has been based on the assumption that the gas is dispersed into bubbles in a completely random way in respect of the energies of the bubbles. The size distribution function of bubbles obtained when surface tension effects are neglected is of the same form as the empirical Nukiyama-Tanasawa distribution, and gives also the size distribution function of droplets consisting of an incompressible liquid when the way the liquid is dispersed into droplets is assumed to be completely random with respect to the volumes of the droplets. The derived size distribution functions agree well with the experimental size distributions of bubbles in water having been generated by an air entrainment process at the surface of the water or behind a ventilated body.     

Activity coefficients of Na2O in molten NaCl,Na2SO4, and Na2CO3

Measurements of the cell

have been used to determine activity coefficients of Na₂O in molten NaCl, Na₂SO₄ and Na₂CO₃. Extreme negative deviations from Raoult's law were observed (γ < 10^?3). In NaCl and Na₂SO₄, γ is independent of concentration below 1 m/o Na₂O, but in Na₂CO₃, the activity is nearly independent of concentration, probably because the oxide reacts with dissolved O₂ to form superoxide (O^?₂).     

Water Governance in Canada: Innovation and Fragmentation

This paper explores Canada's approach to water governance. It argues that fragmented governance has had negative impacts on Canada's ability to manage water resources adequately (particularly in the context of urbanization, agriculture and resource extraction), and to deal with new issues (such as climate change). Further, it argues that Canada's highly decentralized approach to water governance creates challenges of integration, coordination and data availability. The paper explores possible future strategies for innovations in water governance that may have the potential to improve water management outcomes.     

Adaptive signal processing of asset price dynamics with predictability analysis

In this paper we illustrate the optimal filtering of log returns of commodity prices in which both the mean and volatility are modulated by a hidden Markov chain with finite state space. The optimal estimate of the Markov chain and the parameters of the price model are given in terms of discrete-time recursive filters. We provide an application on a set of high frequency gold price data for the period 1973-2006 and analyse the h-step ahead price predictions against the Diebold-Kilian metric. Within the modelling framework where the mean and volatility are switching regimes, our findings suggest that a two-state hidden Markov model is sufficient to describe the dynamics of the data and the gold price is predictable up to a certain extent in the short term but almost impossible to predict in the long term. The proposed model is also benchmarked with ARCH and GARCH models with respect to price predictability and forecasting errors.     

Application of virtual reality for peritoneal dialysis exchange learning in patients with end-stage renal disease and cognitive impairment

Virtual Reality - Cognitive impairment is not uncommon in patients with end-stage renal disease and can make it more difficult for these patients to carry out peritoneal dialysis (PD) on their own....     

Quality of life development during initial hemodialysis therapy and association with loss of residual renal function

Introduction: Health related quality of life (HRQOL) is markedly reduced in hemodialysis patients compared to the general population. We investigated the course of self‐reported HRQOL over time and the association with selected factors, focusing on changes in glomerular filtration rate (GFR). Methods: Eighty‐two newly started hemodialysis patients from the SAFIR cohort filled out the Kidney Disease Quality of Life Short Form Version 1.3 (KDQOL‐SF^TM) questionnaire at baseline, 6 and 12 months. The SAFIR study was a randomized, placebo‐controlled, double‐blind intervention study, examining the effects of the angiotensin II receptor blocker irbesartan. HRQOL was a secondary outcome measure. Main inclusion criteria: Dialysis vintage <1 year, left ventricular ejection fraction >30% and urinary output >300 mL/day. GFR was measured with mean creatinine and urea clearance from 24‐hour urine collections at baseline, 6 and 12 months. Findings: Irbesartan treatment did not affect HRQOL. Patients were pooled into one group for further analyses. Decline in GFR correlated significantly with decreasing HRQOL over time. HRQOL was stable over time, with a slight nonsignificant tendency toward improved HRQOL. The largest HRQOL‐differences (positive values equal improved HRQOL) observed during the 12 month study period were (mean[95% confidence interval]): Burden of kidney disease:6.4[?2.2;15.0], Role limitations‐physical:12.7[?2.1;27.5], and Role limitations‐emotional:9.7[?5.2;24.6]. Comorbidity, especially diabetes, hospital admissions, female gender, and age were strongly associated with lower HRQOL in cross sectional analysis. Discussion: Preservation of residual renal function seems to be important for HRQOL. In newly started HD patients, HRQOL showed little change after 12 months. HRQOL was negatively affected by comorbidity, especially diabetes, hospital admissions, female gender, and age.