73,858 research outputs found
Effect of synthetic and bovine milk conjugated linoleic acid (CLA) on immune function : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Nutrition Science at Massey University
CLA is a collective name for a mixture of positional and geometrical isomers of linoleic acid (c-9, c-12-octadecadioenic acid) which possess conjugated double bonds. CLA occurs in a variety of foods, but is present at higher concentrations in products from ruminants. Milk fat is the richest natural source of CLA. The objective of this research was to examine the immunomodulatory properties of CLA (both synthetic and natural CLA derived from bovine milk fat). Two experiments were conducted at the Milk and Health Research Centre, Massey University, Palmerston North, New Zealand. The aim of the first experiment was to investigate the dose effect of different concentrations of synthetic CLA (Tonalin) on immune function. Mice were fed either skim milk powder based diet or the same diet supplemented with 0.1, 0.25, 0.5, 1.0 or 2.0% synthetic CLA (Tonalin) by weight. Animals were immunised orally with a mixture of polio vaccine in sodium bicarbonate (25μl) and subcutaneously with Fluvax and Tetanus toxoid vaccine on days 7 and 21. After 4 weeks feeding, mice were euthanased by isoflurane overdose. Various immune parameters were measured and the results showed that synthetic CLA (Tonalin) enhanced a range of immune functions. Synthetic CLA stimulated PHA induced T lymphocyte proliferation at 0.25, 0.5 and 1.0% as compared with the control group (p < 0.05). Synthetic CLA enhanced macrophage phagocytosis in a dose dependent manner. Synthetic CLA enhanced antibody responses (mucosal and systemic) to vaccines (polio vaccine, Fluvax and Tetanus toxoid). Natural killer cell activity was significantly enhanced in mice fed 0.25 and 0.5% CLA. In general, 0.25% CLA was regarded as the best CLA level which achieved optimal immunoregulating effects. The aim of the second experiment was to examine the effect of natural CLA derived from milk fat on immune responses in mice. Mice were fed a skim milk powder (SMP) based diet. The control diet was skim milk powder only, without any CLA or milk fat supplementation. The dietary treatments were: ordinary milk fat, fractionated milk fat (1st stage), 0.2% synthetic CLA (Tonalin) and CLA enriched milk fat. Animals were fed these diets for 28 days. Mice were immunised orally with a mixture of polio vaccine/ovalbumin/cholera toxin in sodium bicarbonate on days 7, 14 and 21 and subcutaneously with Fluvax and ADT (Diptheria and Tetanus toxoid vaccine) on days 7 and 21. Natural CLA was found to stimulate PHA and Con A induced T lymphocyte blastogenesis. Supplementation with natural CLA also led to increased antibody responses to vaccines and increased CD25+ populations in peripheral blood in mice. Natural CLA also enhanced macrophage phagocytosis. Synthetic CLA enhanced a range of immune functions which is consistent with the results in the first experiment. It is noted that although the CLA content is low in milk fat, the natural CLA derived from milk fat expressed potent effects in enhancing the growth of immune cells and promoting a range of immune functions in mice. Key words: conjugated linoleic acid (CLA), lymphocyte, macrophage, immunity, milk fa
A bipolar outflow from the massive protostellar core W51e2-E
We present high resolution images of the bipolar outflow from W51e2, which
are produced from the Submillimeter Array archival data observed for CO(3-2)
and HCN(4-3) lines with angular resolutions of 0.8" x 0.6" and 0.3" x 0.2",
respectively. The images show that the powerful outflow originates from the
protostellar core W51e2-E rather than from the ultracompact HII region W51e2-W.
The kinematic timescale of the outflow from W51e2-E is about 1000 yr, younger
than the age (~5000 yr) of the ultracompact HII region W51e2-W. A large mass
loss rate of ~1 x 10^{-3} M_sun yr^{-1} and a high mechanical power of 120
L_sun are inferred, suggesting that an O star or a cluster of B stars are
forming in W51e2-E. The observed outflow activity along with the inferred large
accretion rate indicates that at present W51e2-E is in a rapid phase of star
formation.Comment: 5 pages, 2 figures, 1 table, accepted for publication in ApJL. v2:
some typos correcte
Clapeyron equation and phase equilibrium properties in higher dimensional charged topological dilaton AdS black holes with a nonlinear source
Using Maxwell's equal area law, we discuss the phase transition of higher
dimensional charged topological dilaton AdS black holes with a nonlinear
source. The coexisting region of the two phases is found and we depict the
coexistence region in diagrams. The two-phase equilibrium curves in
diagrams are plotted, and we take the first order approximation of volume
in the calculation. To better compare with a general thermodynamic system, the
Clapeyron equation is derived for higher dimensional charged topological black
hole with a nonlinear source. The latent heat of isothermal phase transition is
investigated. We also study the effect of the parameters of the black hole on
the region of two-phases coexistence. The results show that the black hole may
go through a small-large phase transition similar to those of usual non-gravity
thermodynamic systems.Comment: 21 pages,25 figures. published version in EPJC. arXiv admin note:
substantial text overlap with arXiv:1411.7202; text overlap with
arXiv:1506.01786, arXiv:hep-th/0605042 by other author
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