Premature aging is associated with higher levels of 8‐oxoguanine and increased DNA damage in the Polg mutator mouse

Mitochondrial dysfunction plays an important role in the aging process. However, the mechanism by which this dysfunction causes aging is not fully understood. The accumulation of mutations in the mitochondrial genome (or “mtDNA”) has been proposed as a contributor. One compelling piece of evidence in support of this hypothesis comes from the Polg ^D257A/D257A mutator mouse (Polg ^mut/mut ). These mice express an error‐prone mitochondrial DNA polymerase that results in the accumulation of mtDNA mutations, accelerated aging, and premature death. In this paper, we have used the Polg ^mut/mut model to investigate whether the age‐related biological effects observed in these mice are triggered by oxidative damage to the DNA that compromises the integrity of the genome. Our results show that mutator mouse has significantly higher levels of 8‐oxoguanine (8‐oxoGua) that are correlated with increased nuclear DNA (nDNA) strand breakage and oxidative nDNA damage, shorter average telomere length, and reduced mtDNA integrity. Based on these results, we propose a model whereby the increased level of reactive oxygen species (ROS) associated with the accumulation of mtDNA mutations in Polg ^mut/mut mice results in higher levels of 8‐oxoGua, which in turn lead to compromised DNA integrity and accelerated aging via increased DNA fragmentation and telomere shortening. These results suggest that mitochondrial play a central role in aging and may guide future research to develop potential therapeutics for mitigating aging process.     

Interactionism and Innateness in the Evolutionary Study of Human Nature

While most researchers who use evolutionary theory to investigatehuman nature especially human sexuality describe themselves as ``interactionists', there is no clear consensus on the meaning of thisterm in this context. By interactionism most people in the fieldmean something like, both nature and nurture ``count' in thedevelopment of human psychology and behavior. Nevertheless, themultidisciplinary nature of evolutionary psychology results in a widevariety of interpretations of this general claim. Today, mostdebates within evolutionary psychology about the innateness of agiven behavioral characteristic or over its development turn as muchon which conception of ``innateness' and ``interactionism' theresearcher holds as on any empirical data they might derive.     

Intercontinental transfer of adult Acipenser oxyrinchus– impact assessment of aviation transport conditions on blood parameters

In order to facilitate intercontinental air transport of live sturgeon broodstock, a simulation test for an 8‐h flight was performed in a pressure chamber (pressure profiles resembling conditions during trans‐Atlantic cargo flights). Atlantic sturgeon (Acipenser oxyrinchus) were maintained in sealed polyethylene bags with water and an oxygen‐enriched atmosphere at a ratio of 1 : 5 : 10 (fish:water:oxygen by volume) over a 10 h period at 15°C water temperature. Minimum pressure during the simulated flight was regulated at an elevation of 2600 m equalling 850 hPa. Decompression and compression phases to simulate takeoff and landing were set at 30 min each. Respiration frequency was recorded during flight simulation. Blood pH, blood pO₂ and pCO₂ as well as Ca²⁺, Na⁺, K⁺, Cl^?, glucose and cortisol, cholesterol and trigycerids were also monitored prior to and after transport (at 12, 24, 36, 280 and 366 h). During exposure in the bags, blood pH decreased from a mean of 7.35 to 7.11 and blood pCO₂ increased from 2.48 to 8.53 hPa. Both parameters revealed the most significant deviations from control levels immediately following the trial, returning to normal levels after 36 h. In contrast, the Na²⁺, Ca²⁺and Cl^? ion as well as glucose concentration required 72 h following the simulated transport until baseline levels were reached. During the subsequent transatlantic transport trials from Canada to Germany, blood parameters were utilized to assess fish recovery following transport. Additionally, testing of the transport water revealed that NH₄–N reached critical levels of 6 mg l^?1 within 16–18 h when the fish were kept in the sealed bags at 10°C. Following transport, adaptation of pH in the water of the rearing facility to levels of pH 6.9–7.0 for 20–28 h minimized toxic NH₃ concentrations and ensured recovery. Recovery times varied to a large extent, influenced by the condition factor of the fish. Fish survival was 100% for 2 months post‐transport, indicating that the critical parameters were met during transport.     

Life Cycle Energy Assessment of Alternative Water Supply Systems (9 pp)

Goal, Scope and Background This paper discusses the merging of methodological aspects of two known methods into a hybrid on an application basis. Water shortages are imminent due to scarce supply and increasing demand in many parts of the world. In California, this is caused primarily by population growth. As readily available water is depleted, alternatives that may have larger energy and resource requirements and, therefore, environmental impacts must be considered. In order to develop a more environmentally responsible and sustainable water supply system, these environmental implications should be incorporated into planning decisions. Methods Comprehensive accounting for environmental effects requires life cycle assessment (LCA), a systematic account of resource use and environmental emissions caused by extracting raw materials, manufacturing, constructing, operating, maintaining, and decommissioning the water infrastructure. In this study, a hybrid LCA approach, combining elements of process-based and economic input-output-based LCA was used to compare three supply alternatives: importing, recycling, and desalinating water. For all three options, energy use and air emissions associated with energy generation, vehicle and equipment operation, and material production were quantified for life-cycle phases and water supply functions (supply, treatment, and distribution). The Water-Energy Sustainability Tool was developed to inform water planning decisions. It was used to evaluate the systems of a Northern and a Southern California water utility. Results and Discussion The results showed that for the two case study utilities desalination had 2–5 times larger energy demand and caused 2–18 times more emissions than importation or recycling, due primarily to the energy-intensity of the treatment process. The operation life-cycle phase created the most energy consumption with 56% to 90% for all sources and case studies. For each water source, a different life-cycle phase dominated energy consumption. For imported water, supply contributed 56% and 86% of the results for each case study; for desalination, treatment accounted for approximately 85%; for recycled water, distribution dominated with 61% and 74% of energy use. The study calculated external costs of air pollution from all three water supply systems. These costs are borne by society, but not paid by producers. The external costs were found to be 6% of desalinated water production costs for both case studies, 8% of imported water production costs in Southern California, and 1–2% for the recycled water systems and for the Northern California utility's imported water system. Conclusion Recycling water was found to be more energy intensive in Northern than in Southern California, but the results for imported water were similar. While the energy demand of water recycling was found to be larger than importation in Northern California, the two alternatives were competitive in Southern California. For all alternatives in both case studies, the energy consumed by system operation dominated the results, but maintenance was also found to be significant. Energy production was found to be the largest contributor in all water provision systems, followed by materials production. The assessment of external costs revealed that the environmental effects of energy and air emissions caused by infrastructure is measurable, and in some cases, significant relative to the economic cost of water. Recommendation and Perspective This paper advocates the necessity of LCA in water planning, and discusses the applicability of the described model to water utilities.     

An analytical method for the separation of dopamine metabolites in cellular extracts by high-pressure liquid chromatography

An analytical scheme using high-performance liquid chromatography (HPLC) has been developed to separate radiolabeled catecholamines in cell extracts derived from mammalian cells grown in tissue culture. Four different types of chromatographic systems have been employed to effect separations of groups of metabolites that possess similar organic functional groups. Data obtained by thin-layer chromatography are also presented and it is demonstrated that HPLC is the system of choice for the separation and quantitative analysis of metabolites of dopamine in physiological fluids.