Blood Cell Membrane Omega-3 (n-3) Fatty Acid Abnormality and Supplementation in Patients with Sickle Cell Anemia

Sickle cell disease (SCD) is a group of autosomal recessive genetic blood disorders caused by a mutation in the sixth codon of the β goblin gene that results in abnormal hemoglobin (Hemoglobin S, HbS) (Knight-Perry et al., 2009; Rees et al., 2010; Serjeant and Serjeant, 2001). The principal phenotypes are homozygous sickle cell (HbSS) disease, sickle cell-hemoglobin C , sickle cell-β0 thalassemia, sickle cell-β1 thalassemia, HbSOArab and HbSDPunjab and HbSLepore Boston SCD (Nagel et al., 2003; Serjeant and Serjeant, 2001). Deoxygenated HbS forms insoluble rigid polymers (sickle) under hypoxic conditions and reverts back to normal on re-oxygenation. However, with repeated cycles of sickling and unsickling, erythrocytes become irreversibly sickled and lose their biconcave shape and fluidity. The primary pathological process in SCD, namely vasoocclusive crisis is a recurrent occlusion of blood vessels which causes ischemia, severe pain episodes (painful crisis), and damage to the brain, eyes, lungs, spleen, liver, and other vital organs (Ballas et al., 2010; Serjeant and Serjeant, 2001). Despite the apparent genetic simplicity, patients with SCD display a remarkable diversity in clinical manifestations and disease severity (Chui and Dover, 2001; Fertrin and Costa, 2010). The Cooperative Study of Sickle Cell Disease (Platt et al., 1991) found that 39% of 3578 patients with SCD did not have painful episodes, whereas 1% had more than six per year. It appears that type and severity of the complication of the disease are modulated by genetic, environmental, and other factors (Sebastiani et al., 2005; Steinberg, 2005)

Natural resources for appropriate water treatment

The high cost of water treatment has rendered provision of good quality water in the developing world difficult. The search for low-cost treatment options is essential in order to provide safe drinking water. This paper presents a study on the use of Moringa oleifera and pumice as low cost natural materials for improving water treatment systems. Moringa oleifera was found to be very effective for coagulating raw turbid water. The coagulant component was isolated from the seed and purified using a single-step ion exchange purification method. The process was standardized and it can be readily scaled up. The use of pumice for dual media filtration was compared against a mono-medium sand filtration system. In a pilot scale study pumice/sand dual media increased the filter run length two-fold and reduced the volume of backwash water by half

Evaluation of models to predict the stoichiometry of volatile fatty acid profiles in rumen fluid of lactating Holstein cows

Volatile fatty acids (VFA), produced in the rumen by microbial fermentation, are the main energy source for ruminants. The VFA profile, particularly the nonglucogenic (acetate, Ac; butyrate, Bu) to glucogenic (propionate, Pr) VFA ratio (NGR), is associated with effects on methane production, milk composition, and energy balance. The aim of this study was to evaluate extant rumen VFA stoichiometry models for their ability to predict in vivo VFA molar proportions. The models were evaluated using an independent data set consisting of 101 treatments from 24 peer-reviewed publications with lactating Holstein cows. All publications contained a full diet description, rumen pH, and rumen VFA molar proportions. Stoichiometric models were evaluated based on root mean squared prediction error (RMSPE) and concordance correlation coefficient (CCC) analysis. Of all models evaluated, the 1998 Friggens model had the lowest RMSPE for Ac and Bu (7.2 and 20.2% of observed mean, respectively). The 2006 Bannink model had the lowest RMSPE and highest CCC for Pr (14.4% and 0.70, respectively). The 2008 Bannink model had comparable predictive performance for Pr to that of the 2006 Bannink model but a larger error due to overall bias (26.2% of MSPE). The 1982 Murphy model provided the poorest prediction of Bu, with the highest RMSPE and lowest CCC (24.6% and 0.15, respectively). The 1988 Argyle and Baldwin model had the highest CCC for Ac with an intermediate RMSPE (0.47 and 8.0%, respectively). The 2006 Sveinbjörnsson model had the highest RMSPE (13.9 and 34.0%, respectively) and lowest CCC (0.31 and 0.40, respectively) for Ac and Pr. The NGR predictions had the lowest RMSPE and highest CCC in the 2 models of Bannink, whereas the lowest predictive performance was in the 2006 Sveinbjörnsson model. It appears that the type of VFA produced is not a simple linear relationship between substrate inputs and pH as currently represented. The analysis demonstrates that most rumen VFA stoichiometric approaches explain a large part of the variation in VFA molar proportions among diets, in particular for Ac, whereas predictive power for Pr and Bu differ largely among approaches. The move toward feed evaluation systems based on animal response might necessitate an improved representation of rumen fermentation, focused on improving our understanding of VFA proportions in diets that vary from the mean

Modelling the lactation curve of dairy cows using the differentials of growth functions

Descriptions of entire lactations were investigated using six mathematical equations. comprising the differentials of four growth functions (logistic. Gompertz, Schumacher and Morgan) and two other equations (Wood and Dijkstra). The data contained monthly milk yield records from 70 first, 70 second and 75 third parity Iranian Holstein cows. Indicators of fit were model behavior, statistical evaluation and biologically meaningful parameter estimates and lactation features. Analysis of variance with equation, parity and their interaction as factors and with cows as replicates was performed to compare goodness of fit of the equations. The interaction of equation and parity was not significant for any statistics, which showed that there vas no tendency For one equation to fit a given parity better than other equations. Although model behaviour analysis showed better performance of growth functions than the Wood and Dijkstra equations in filling the individual lactation curves, statistical evaluation revealed that there was no significant difference between file goodness of fit of the different equations. Evaluation of lactation features showed that the Dijkstra equation was able to estimate the initial milk yield and peak yield more accurately than the other equations. Overall evaluation of the different equations demonstrated the potential of the differentials of simple empirical growth functions used in file Current study as equations for fitting monthly milk records of Holstein dairy cattle

Child labour and economic growth

This paper examines the relationship between national income and child labour. We are particularly interested in evaluating the economic role of children at different stages of development. Our objective is to show that in the aggregate, at a low level of development the direction of the relationship between the incidence of child labour and per capita income is indefinite. Child labour may increase or decrease with income. Forecasts of the child labour force participation rate as well as per capita gross domestic product are made for each country in the sample. We also forecast future levels of the primary net enrollment ratio in an effort to provide empirical support for our policy recommendations. Using panel data methodology, we find evidence of an inverted-U, Kuznets-like relationship between the child labour force participation rate and per capita GDP. Holding all else constant, forecast results suggest that for those countries on upward sloping part of the curve, child labour is a problem that will persist for many years to come. The growth rates of per capita GDP required to reach 10 per cent child labour by the target date, 2029, range from 2 per cent to 15 per cent. Our results highlight the importance of the identification of other aspects of development as determinants of child labour levels, as well as exploring the role of government policy. Further research opportunities are also presented

A review of mathematical functions for the analysis of growth in poultry

Poultry industries face various decisions in the production cycle that affect the profitability of an operation. Predictions of growth when the birds are ready for sale are important factors that contribute to the economy of poultry operations. Mathematical functions called ‘growth functions’ have been used to relate body weight (W) to age or cumulative feed intake. These can also be used as response functions to predict daily energy and protein dietary requirements for maintenance and growth (France et al., 1989). When describing growth versus age in poultry, a fixed point of inflexion can be a limitation with equations such as the Gompertz and logistic. Inflexion points vary depending on age, sex, breed and type of animal, so equations such as the Richards and López are generally recommended. For describing retention rate against daily intake, which generally does not exhibit an inflexion point, the monomolecular would appear the function of choice

Phosphorylation of protein kinase B, the key enzyme in insulin signalling cascade, is enhanced in linoleic and arachidonic acid treated HT29 and HepG2 cells

Objective: Defects in insulin signalling pathway have been implicated in the pathogenesis of impaired glucose uptake, insulin resistance and type II diabetes. However, the specific defects that precipitate these abnormalities are yet to be fully elucidated. The plasma membrane embedded insulin receptor transmembrane protein, after binding to insulin, initiates a cascade of phosphorylation which leads to the activation of protein kinase B (AKT) and subsequently to initiation of some metabolic actions of insulin. The activities of this receptor, insulin binding and tyrosine kinase activation, is dependent on its plasma lipid environment. There are scarcity of published data on the influence of omega-3 and -6 polyunsaturated fatty acids on insulin response. Moreover, the findings of the published investigations, most of which have used omega-3 and -6 PUFA blend, have been inconclusive. Hence, a need for well- thought-out further research. The aim was to elucidate the effect of treatments with LNA, ARA, ALA, DHA, and EPA on cell membrane composition and consequently on insulin signalling pathway, specifically AKT phosphorylation. Research Methods and Procedures: Human colon adenocarcinoma (HT29) and liver hepatocellular (HepG2) cells were treated with or without 40 µM of linoleic (LNA), arachidonic (ARA), alpha-linolenic (ALA), eicosapentaenoic (EPA) or docosahexaenoic (DHA) for 48 hours. Fatty acids composition of phosphatidylcholine (PtdCho) and phosphatidylethanolamine (PtdEtn) from the treated cells by capillary gas liquid chromatograph. Cells were incubated for 30 minutes with or without human insulin (50ng/ml) and the phosphorylation of AKT assessed with the use of western blotting. Results: The fatty acids were incorporated in PtdCho and PtdEtn of both cell lines; but, the level of incorporation was higher in HT29. Phosphorylation of AKT increased when HT29 was treated with LNA (P<0.05) and ARA (P<0.01), but not with ALA, EPA or DHA. A similar but non-significant increase in AKT phosphorylation was observed in LNA and ARA treated HepG2 cells. Conclusion: The finding of this investigation demonstrates, plasma membrane lipid bilayer enrichment with LNA or ARA treatment enhances insulin action by AKT activation

Omega- 3 fatty acids are potential therapy for patients with sickle cell disease

A correspondence letter to “Nature Reviews Disease Primers” about the therapeutic potential of omega 3 fatty acids for patients with sickle cell disease

A universal method for assessing intrinsic expansiveness of soils.

Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2004.Many of the attempts made over the past six decades to find a universal system for assessing expansiveness of soils using soil index data have failed to follow the basic principles of soil mechanics. By overcoming most of these limitations Gourley and Schreiner (1993a) developed a new procedure that allows comparison of intrinsic expansiveness of soil samples prepared to have stable micro-fabric and consistent stress history. In this research, the same procedure is used on twenty-seven natural clayey soil samples of varying geological, geomorphological and geographical origin obtained from Kenya, Sudan, Eritrea and South Africa. Each of these samples was tested for Atterberg limits, volume change behaviours and soil suction. Statistical analysis was conducted on different soil parameters derived from these tests to obtain a significant relationship with their intrinsic expansiveness using measured swell. The analysis confirmed that most of the significant relationships obtained contain swell index, C*5' showing the identicalness of the soil properties responsible for volume change behaviour of both saturated and unsaturated clayey soils. Depending on the cost and the significance, the analysis recommended three major models that can be used as a screening system in the assessment of intrinsic expansiveness. For any soil it is possible to obtain preliminary information regarding its intrinsic expansiveness using the cheapest of the recommended models that needs liquid and plastic limit tests and hydrometer analysis, which are the routine tests of geotechnical site investigation. A more detailed assessment can be achieved by including only t he shrinkage test. The most reliable assessment needs addition of consolidation test with the unloading stage. All of the models allow obtaining information regarding the intrinsic expansiveness of soils as early as site investigation stage for successful engineering design. Moreover, they are anticipated to promote worldwide exchange of information regarding these problematic soils