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Central inflammation and leptin resistance are attenuated by ginsenoside Rb1 treatment in obese mice fed a high-fat diet
Get PDFA low-grade pro-inflammatory state is at the pathogenic core of obesity and type 2 diabetes. We tested the hypothesis that the plant terpenoid compound ginsenoside Rb1 (Rb1), known to exert anti-inflammatory effects, would ameliorate obesity, obesity-associated inflammation and glucose intolerance in the high-fat diet-induced obese mouse model. Furthermore, we examined the effect of Rb1 treatment on central leptin sensitivity and the leptin signaling pathway in the hypothalamus. We found that intraperitoneal injections of Rb1 (14 mg/kg, daily) for 21 days significantly reduced body weight gain, fat mass accumulation, and improved glucose tolerance in obese mice on a HF diet compared to vehicle treatment. Importantly, Rb1 treatment also reduced levels of pro-inflammatory cytokines (TNF-α, IL-6 and/or IL-1β) and NF-κB pathway molecules (p-IKK and p-IκBα) in adipose tissue and liver. In the hypothalamus, Rb1 treatment decreased the expression of inflammatory markers (IL-6, IL-1β and p-IKK) and negative regulators of leptin signaling (SOCS3 and PTP1B). Furthermore, Rb1 treatment also restored the anorexic effect of leptin in high-fat fed mice as well as leptin pSTAT3 signaling in the hypothalamus. Ginsenoside Rb1 has potential for use as an anti-obesity therapeutic agent that modulates obesity-induced inflammation and improves central leptin sensitivity in HF diet-induced obesity. © 2014 Public Library of ScienceAcquired from the Public Library of Science. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. 2014 Wu et al
Adolescent rats find repeated Δ9-THC less aversive than adult rats but display greater residual cognitive deficits and changes in hippocampal protein expression following exposure
No full textThe current study examined whether adolescent rats are more vulnerable than adult rats to the lasting adverse effects of cannabinoid exposure on brain and behavior. Male Wistar rats were repeatedly exposed to Delta-9-tetrahydrocannabinol (Delta(9)-THC, 5 mg/kg i.p.) in a place-conditioning paradigm during either the adolescent (post-natal day 28+) or adult (post-natal day 60+) developmental stages. Adult rats avoided a Delta(9)-THC-paired environment after either four or eight pairings and this avoidance persisted for at least 16 days following the final Delta(9)-THC injection. In contrast, adolescent rats showed no significant place aversion. Adult Delta(9)-THC-treated rats produced more vocalizations than adolescent rats when handled during the intoxicated state, also suggesting greater drug-induced aversion. After a 10-15 day washout, both adult and adolescent Delta(9)-THC pretreated rats showed decreased social interaction, while only Delta(9)-THC pretreated adolescent rats showed significantly impaired object recognition memory. Seventeen days following their last Delta(9)-THC injection, rats were euthanased and hippocampal tissue processed using two-dimensional gel electrophoresis proteomics. There was no evidence of residual Delta(9)-THC being present in blood at this time. Proteomic analysis uncovered 27 proteins, many involved in regulating oxidative stress/mitochondrial functioning and cytoarchitecture, which were differentially expressed in adolescent Delta(9)-THC pretreated rats relative to adolescent controls. In adults, only 10 hippocampal proteins were differentially expressed in Delta(9)-THC compared to vehicle-pretreated controls. Overall these findings suggest that adolescent rats find repeated Delta(9)-THC exposure less aversive than adults, but that cannabinoid exposure causes greater lasting memory deficits and hippocampal alterations in adolescent than adult rats. © 2018 Springer Natur
Anisotropy in the thermal expansion of uranium silicide measured by neutron diffraction
No full textIn-situ neutron diffraction patterns were collected for a sample of as-cast U3Si2 during heating to 1600 °C. Anomalous changes were observed above 1000 °C, including the formation of a new diffraction peak not belonging to P4/mbm U3Si2, unequal changes in the peak intensities and onset of anisotropic lattice expansion. The large data-set enabled derivation of a function-fitted isotropic thermal expansion coefficient to high precision, in close agreement with previous dilatometry results but reducing linearly with temperature over the studied interval. Anisotropy in the instantaneous lattice thermal expansion corresponded to anomalies reported by White et al. (2015) at a similar temperature. © Elsevier B.
Synroc tailored waste forms for actinide immobilization
No full textSince the end of the 1970s, Synroc at the Australian Nuclear Science and Technology Organisation (ANSTO) has evolved from a focus on titanate ceramics directed at PUREX waste to a platform waste treatment technology to fabricate tailored glass–ceramic and ceramic waste forms for different types of actinide, high- and intermediate level wastes. The particular emphasis for Synroc is on wastes which are problematic for glass matrices or existing vitrification process technologies. In particular, nuclear wastes containing actinides, notably plutonium, pose a unique set of requirements for a waste form, which Synroc ceramic and glass-ceramic waste forms can be tailored to meet. Key aspects to waste form design include maximising the waste loading, producing a chemically durable product, maintaining flexibility to accommodate waste variations, a proliferation resistance to prevent theft and diversion, and appropriate process technology to produce waste forms that meet requirements for actinide waste streams. Synroc waste forms incorporate the actinides within mineral phases, producing products which are much more durable in water than baseline borosilicate glasses. Further, Synroc waste forms can incorporate neutron absorbers and 238U which provide criticality control both during processing and whilst within the repository. Synroc waste forms offer proliferation resistance advantages over baseline borosilicate glasses as it is much more difficult to retrieve the actinide and they can reduce the radiation dose to workers compared to borosilicate glasses. Major research and development into Synroc at ANSTO over the past 40 years has included the development of waste forms for excess weapons plutonium immobilization in collaboration with the US and for impure plutonium residues in collaboration with the UK, as examples. With a waste loading of 40–50 wt.%, Synroc would also be considered a strong candidate as an engineered waste form for used nuclear fuel and highly enriched uranium-rich wastes. © 2011–2018 by Walter de Gruyter Gmb
The new confocal heavy ion microprobe beamline at ANSTO: the first microprobe resolution tests and applications for elemental imaging and analysis
No full textThe Centre for Accelerator Science facility at ANSTO has been expanded with the new NEC 6MV “SIRIUS” accelerator system in 2015. In this paper we present a detailed description of the new nuclear microprobe–Confocal Heavy Ion Micro-Probe (CHIMP) together with results of the microprobe resolution testing and the elemental analysis performed on typical samples of mineral ore deposits and hyper-accumulating plants regularly measured at ANSTO. The CHIMP focusing and scanning systems are based on the OM-150 Oxford quadrupole triplet and the OM-26 separated scan-coil doublet configurations. A maximum ion rigidity of 38.9amu-MeV was determined for the following nuclear microprobe configuration: the distance from object aperture to collimating slits of 5890mm, the working distance of 165mm and the lens bore diameter of 11mm. The overall distance from the object to the image plane is 7138mm. The CHIMP beamline has been tested with the 3MeV H+ and 6MeV He2+ ion beams. The settings of the object and collimating apertures have been optimized using the WinTRAX simulation code for calculation of the optimum acceptance settings in order to obtain the highest possible ion current for beam spot sizes of 1μm and 5μm. For optimized aperture settings of the CHIMP the beam brightness was measured to be ∼0.9pAμm−2mrad−2 for 3MeV H+ ions, while the brightness of ∼0.4pAμm−2mrad−2 was measured for 6MeV He2+ ions. The smallest beam sizes were achieved using a microbeam with reduced particle rate of 1000Hz passing through the object slit apertures several micrometers wide. Under these conditions a spatial resolution of ∼0.6μm×1.5μm for 3MeV H+ and ∼1.8μm×1.8μm for 6MeV He2+ microbeams in horizontal (and vertical) dimension has been achieved. The beam sizes were verified using STIM imaging on 2000 and 1000mesh Cu electron microscope grids. © 2017 Elsevier B.V
In vivo PET imaging with [18F]FDG to explain improved glucose uptake in an apolipoprotein A-I treated mouse model of diabetes
No full textType 2 diabetes is characterised by decreased HDL levels, as well as the level of apolipoprotein A-I (apoA-I), the main apolipoprotein of HDLs. Pharmacological elevation of HDL and apoA-I levels is associated with improved glycaemic control in patients with type 2 diabetes. This is partly due to improved glucose uptake in skeletal muscle.© 2016 Springer Natur
Towards sustainable energy. Generation of hydrogen fuel using nuclear energy
No full textThe increasing demand for sustainable energy results in the development of new technologies of energy generation. The key objective of hydrogen economy is the introduction of hydrogen as main energy carrier, along with electricity, on a global scale. The key goal is the development of hydrogen-related technologies needed for hydrogen generation, hydrogen storage, hydrogen transportation and hydrogen distribution as well as hydrogen safety systems. It is commonly believed that hydrogen is environmentally clean since its combustion results in the formation of water. However, the technology currently employed for the generation of hydrogen from natural gas, does in fact lead to the emission of greenhouse gases and climate change. Therefore, the key issues in the introduction of hydrogen economy involve the development of environmentally clean hydrogen production technology as well as storage and transport. The clean options available for hydrogen generation using nuclear energy; such as advanced nuclear fission and, ultimately, nuclear fusion, are discussed. The latter, which is environmentally clean, is expected to be the primary approach in the production of hydrogen fuel at the global scale. The present work considers the effect of hydrogen on properties of TiO2 and its solid solutions in the contexts of photocatalytic energy conversion and the effect of tritium on advanced tritium breeders. © 2016 Hydrogen Energy Publications LLC
Wormlike micelle formation of novel alkyl-tri(ethylene glycol)-glucoside carbohydrate surfactants: Structure–function relationships and rheology
No full textCarbohydrates are appealing non-ionic surfactant head-groups as they are naturally abundant, generally biocompatible and biodegradable, and readily functionalized. Here, seven novel carbohydrate based surfactants (CBS) have been synthesized that contain a tri-ethylene glycol (TEG) linker between a glucose head-group and alkyl tail-group, with linear saturated (C8–18) and unsaturated (C18:1) alkyl chains. The aqueous adsorption and self-assembly of these surfactants was explored using tensiometry and small- and ultra-small-angle neutron scattering (SANS and USANS). With SANS we observed elongation from spherical to cylindrical micelles with increasing alkyl chain length. C16 and C18 chains exhibited pronounced Krafft points, yet formed worm-like micelles as single components upon heating to 43 and 48 °C respectively. The introduction of mono-unsaturation in the form of a C18:1 chain reduced the Krafft point and gave a surfactant that produced worm-like micelles in water without additives at room temperature. We also observed micellar elongation for C12 and C14 chains at 50 °C due to dehydration of the TEG linker. The room temperature worm-like micelles were further characterized using rheo-SANS and rheology, revealing the C18:1 surfactant to exhibit near ideal Maxwell behavior at low concentrations (2.9 wt.%). These results provide insight into structure-function relationships for CBS, and demonstrate a promising molecular candidate for the formation of viscoelastic worm-like micellar solutions. © 2018 Elsevier Inc
Identifying historical flood deposits in a sediment cores
No full textRiver floods are a risk, not only because of the large volume of water that is mobilized, but also
because of the potentially high level of nutrients and pollutants contained in these waters. There is
limited understanding of flood water quality, which hinders the implementation of appropriate
mitigation strategies. Therefore we must better understand the trends in flood water quality to protect society and the natural environment from risks associated with poor quality flood waters. Fluvial flood water quality data could be obtained using sediment cores from floodplains, as sediment cores can preserve historical flood deposits and can also be used to infer long term trends in the water quality of aquatic environments.
This presentation aims to identify and separate flood-deposited fluvial sediments from in-situ biogenic sediments in a sediment core from a floodplain lake, and to then identify the pollutant levels contained in these flood-deposited sediments. The Yarra River (South-East Australia) and its floodplain lake
(Willsmere Billabong) was used as a case study. Cores taken from Willsmere Billabong were
analysed using the ITRAX micro-X-Ray Fluorescence (XRF) core scanner and the optical and
radiographic images, magnetic susceptibility and elemental composition profiles were used to infer
the sediment type and origins.
Using the data obtained from the core scanner, we found that flooding frequency of the Yarra River
into Willsmere Billabong decreased in the early to mid-20th century. This is most likely due to
increased water extraction with the construction of large reservoirs in the upper river catchment in 1927, 1932 and 1957. Indeed, there is also a decrease in measured flow rates for the Yarra River.
Having identified the flood-deposited sediments within the Willsmere Billabong sediment cores, we
have determined pollutant levels within the flood-deposited sediment layers, to identify water quality trends in river flood water quality
Groundwater systems in northern Australia – are they suitable for a northern food bowl: evidence from residence times and geochemical analyses of ground and surface waters in the Lawn Hill region, northwest Queensland
No full textWater resources in the northern regions of Australia have become increasingly important with the possible development of a northern ‘food-bowl’. Understanding the chemistry, flow systems, and mean residence time (MRT) of groundwater systems in this region is therefore essential.
The Lawn Hill region of northwest Queensland is subjected to a semi-arid monsoonal climate with an average of 542 mm/a – the majority falling in the warmer months through November–March. Due to the polarity of rainfall, most streams run dry during the dry season. However, four major perennial streams are maintained by groundwater discharge, highlighting the importance of groundwater–surface water interaction and our understanding of such systems. The regional geology is dominated by the Barkly Tableland, an expansive Cambrian carbonate plateau, or
siliciclastic formations of the Proterozoic Mount Isa Inlier. The carbonate and siliciclastic lithologies exhibit variable influences on groundwater chemistry and flow. There are
distinct differences in chemical signatures whereby the carbonate-hosted groundwater was found to be strongly influenced by carbonate dissolution with little evidence of evapotranspirative enrichment as indicated by both Cl
concentrations and stable water isotopes (SWI). Conversely, major ion chemistry and SWI composition of the siliciclastic-hosted groundwaters suggest they are strongly influenced by evapotranspirative enrichment and less by
later water–rock interactions (though these do impart a signature on groundwater chemistry). Importantly, the
limited influence of evapotranspiration on carbonate-hosted groundwater with TDS values ranging 540–611 mg/L
means these waters are classified as freshwater and represent a low–medium irrigation salinity risk. Comparatively,
the siliciclastic-hosted groundwaters have much higher TDS values (599–7204 mg/L), which spans the fresh–brackish–saline classifications and represents a medium–high salinity risk. These differences highlight the fact that suitability of groundwater for irrigation purposes greatly depends on the geological controls through water–rock
interactions and influence on groundwater infiltration.
The mean residence time (MRT) of groundwater is an important indicator for groundwater sustainability. Again, there is a clear distinction between carbonate and siliciclastic hosted groundwaters. Both tritium and radiocarbon analyses of dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC) indicate a modern age for carbonate groundwaters with fast recharge indicating the carbonate groundwater is less susceptible to depletion but more susceptible to anthropogenic influences. Comparatively, measurable tritium concentrations in siliciclastic
groundwaters indicate a modern system; however, DIC and DOC radiocarbon analyses indicate a much older groundwater up to ca 10 000 a (depending on the flow model applied). The differences between tritium and
radiocarbon MRT may indicate more complex mixing between young and old groundwater and slower recharge, suggesting siliciclastic groundwaters may be susceptible to depletion