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Human activities are drastically altering water and material flows in river systems across Asia. These anthropogenic perturbations have rarely been linked to the carbon (C) fluxes of Asian rivers that may account for up to 40-50% of the global fluxes. This review aims to provide a conceptual framework for assessing the human impacts on Asian river C fluxes, along with an update on anthropogenic alterations of riverine C fluxes. Drawing on case studies conducted in three selected rivers (the Ganges, Mekong, and Yellow River) and other major Asian rivers, the review focuses on the impacts of river impoundment and pollution on CO2 outgassing from the rivers draining South, Southeast, and East Asian regions that account for the largest fraction of river discharge and C exports from Asia and Oceania. A critical examination of major conceptual models of riverine processes against observed trends suggests that to better understand altered metabolisms and C fluxes in "anthropogenic land-water-scapes", or riverine landscapes modified by human activities, the traditional view of the river continuum should be complemented with concepts addressing spatial and temporal discontinuities created by human activities, such as river impoundment and pollution. Recent booms in dam construction on many large Asian rivers pose a host of environmental problems, including increased retention of sediment and associated C. A small number of studies that measured greenhouse gas (GHG) emissions in dammed Asian rivers have reported contrasting impoundment effects: decreased GHG emissions from eutrophic reservoirs with enhanced primary production vs. increased emissions from the flooded vegetation and soils in the early years following dam construction or from the impounded reaches and downstream estuaries during the monsoon period. These contrasting results suggest that the rates of metabolic processes in the impounded and downstream reaches can vary greatly longitudinally over time as a combined result of diel shifts in the balance between autotrophy and heterotrophy, seasonal fluctuations between dry and monsoon periods, and a long-term change from a leaky post-construction phase to a gradual C sink. The rapid pace of urbanization across southern and eastern Asian regions has dramatically increased municipal wa- ter withdrawal, generating annually 120 km3 of wastewater in 24 countries, which comprises 39% of the global municipal wastewater production. Although municipal wastewater constitutes only 1% of the renewable surface water, it can disproportionately affect the receiving river water, particularly downstream of rapidly expanding metropolitan areas, resulting in eutrophication, increases in the amount and lability of organic C, and pulse emissions of CO2 and other GHGs. In rivers draining highly populated metropolitan areas, lower reaches and tributaries, which are often plagued by frequent algal blooms and pulsatile CO2 emissions from urban tributaries delivering high loads of wastewater, tended to exhibit higher levels of organic C and the partial pressure of CO2 (pCO2) than less impacted upstream reaches and eutrophic impounded reaches. More field measurements of pCO2, together with accurate flux calculations based on river-specific model parameters, are required to provide more accurate estimates of GHG emissions from the Asian rivers that are now underrepresented in the global C budgets. The new conceptual framework incorporating discontinuities created by impoundment and pollution into the river continuum needs to be tested with more field measurements of riverine metabolisms and CO2 dynamics across variously affected reaches to better constrain altered fluxes of organic C and CO2 resulting from changes in the balance between autotrophy and heterotrophy in increasingly human-modified river systems across Asia and other continents. [ABSTRACT FROM AUTHOR]

Background: Mupirocin is a topical antibacterial drug used for the treatment of staphylococcal infections, including meticillin‐resistant Staphylococcus pseudintermedius (MRSP). The recent emergence of resistance to mupirocin is a major concern in many countries. Objectives: This study investigated the prevalence and genotype of mupirocin‐resistant S. pseudintermedius isolated from pet dogs with pyoderma. Samples: A total of 110 clinical isolates of S. pseudintermedius were collected from dogs with pyoderma (n = 110) between July 2010 and September 2016. All animals were client‐owned dogs. Methods: Low‐ and high‐level mupirocin resistance were evaluated with both the broth microdilution and disk diffusion tests. Mupirocin resistance in S. pseudintermedius isolates was confirmed by genetic analysis of the ileS‐2 and naïve ileS genes. Results: MRSP and meticillin‐susceptible S. pseudintermedius were detected in 69 and 41 dogs, respectively. One MRSP strain was highly resistant to mupirocin and contained the high‐level mupirocin resistance gene ileS‐2. There were no low‐level mupirocin‐resistant isolates. Conclusion and clinical importance: Mupirocin is a useful topical antibacterial for MRSP, but a clinical MRSP isolate that had not previously been exposed to mupirocin exhibited the high‐level mupirocin resistance in phenotype and genotype. Therefore, continuous monitoring for mupirocin resistance is important in small animal practice. [ABSTRACT FROM AUTHOR]

Muscle atrophy, a reduction of muscle mass, strength, and volume, results from reduced muscle use and plays a key role in various muscular diseases. In the microgravity environment of space especially, muscle atrophy is induced by muscle inactivity. Exposure to microgravity induces muscle atrophy through several biological effects, including associations with reactive oxygen species (ROS). This study used 3D-clinostat to investigate muscle atrophy caused by oxidative stress in vitro, and sciatic denervation was used to investigate muscle atrophy in vivo. We assessed the effect of Oenothera odorata root extract (EVP) on muscle atrophy. EVP helped recover cell viability in C2C12 myoblasts exposed to microgravity for 24 h and delayed muscle atrophy in sciatic denervated mice. However, the expressions of HSP70, SOD1, and ceramide in microgravity-exposed C2C12 myoblasts and in sciatic denervated mice were either decreased or completely inhibited. These results suggested that EVP can be expected to have a positive effect on muscle atrophy by disuse and microgravity. In addition, EVP helped characterize the antioxidant function in muscle atrophy. [ABSTRACT FROM AUTHOR]