Revisiting cobalt chloride preconditioning to prevent hypobaric hypoxia-induced damage: identification of global proteomic alteration and key networks

Several studies have supported the hypoxia mimetic roles and cytoprotective properties of cobalt chloride in vitro and in vivo. However, a clear understanding of biological process-based mechanism that integrates the available information remains unknown. This study was aimed to explore the potential mechanism of cobalt chloride deciphering its benefits and well-known physiological challenge caused by hypobaric hypoxia that reportedly affects nearly 24 % of the global population. In order to explore the mechanism of CoCl₂, we used global proteomic and systems biology approach in rat model to provide a deeper insight into molecular mechanisms of preconditioning. Furthermore, key conclusions were drawn based on biological network analysis and their enrichment with ontological overlaps. The study was further strengthened by consistent identification of validation of proteins using immunoblotting. CoCl₂-pretreated animals exposed to hypoxia showed two significant networks, one lipid metabolism and other cell cycle associated, with a total score of 23 and eight focus molecules. In this study, we delineated two primary routes: one, by direct modulation of reactive oxygen species metabolism and, second, by regulation of lipid metabolism which was not known until now. The previously known benefits of cobalt chloride during physiological challenge by hypobaric hypoxia are convincing and could be explained by some basic set of metabolic and molecular reorganization within the hypoxia model. Interestingly, we also observed some of the completely unknown roles of cobalt chloride such as regulation of lipid that could undulate the translational roles of cobalt chloride supplementation beyond hypoxia preconditioning.     

Distribution and microhabitats of freshwater mussels in waterbodies in the terrestrialized floodplains of a lowland river

Even when anthropogenically altered, river floodplains continue to contribute to biodiversity. This study examined the distribution of freshwater mussels in relation to environmental factors in waterbodies in the terrestrialized floodplain of a lowland river. Mussels were captured, and environmental measurements were taken in November of 2013 and 2014 in quadrats established in three floodplain waterbodies (FWBs), which were isolated from the main river channel. Among the three FWBs, mussel abundance was highest in a shallow FWB (depth range 18–45 cm) that had intermediate conditions of mud depth and fine sediment rate. Mussel abundance showed a hump-shaped relationship with water depth (the peak 45–50 cm) and mud depth (the peak 8–12 cm). Mussel abundance was also negatively related to the abundance of benthic litter. Litter abundance was positively related to branch abundance and the presence of tree cover, and negatively related to the distance to tree cover, indicating that benthic litter was derived from riparian trees. Our results indicate that relatively shallow (≤ 50 cm) FWBs with moderately accumulated mud, which are not scoured even during flooding, appear to be suitable habitats for mussels. Moreover, it is possible that riparian trees negatively impact mussel distribution in FWBs. Possible short-term measures for improving mussel habitat in FWBs may include the elimination of riparian trees and benthic litter.     

Py-GC/MS analysis of sediments from Lake Biwa,Japan: characterization and sources of humic acids

Humic substances extracted and purified from bottom sediments of northern Lake Biwa, Japan, in November 2012 and 2013 were characterized using elemental analysis, Fourier-transform infrared spectroscopy, hydrogen-1 nuclear magnetic resonance (¹H NMR) analysis, and pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). The infrared (IR) bands in the spectra of humic acids showed the presence of amide linkages and polysaccharides. Results of ¹H NMR analysis showed that the humic acids contained approximately twice the number of aliphatic protons as those in the Japanese soil standards used for comparison. Results of the Py-GC/MS analysis, which evaluates pyrolysis temperature dependency of the amount of pyrolysis products, showed that the generation of pyrolysis products in humic acids also differed from that in Japanese soil standards but was similar to that of phytoplankton in Lake Biwa. This analysis method is the first to provide extensive information about the chemical structure of humic substances; conventional Py-GC/MS provides limited information for a single temperature. Data suggest that humic acids in lake sediments are related to chemical characteristics of phytoplankton. Results shed new light on the origins of humic substances in deep-water-lake sediments and provide insights into material recycling in such sediments.     

Characteristic seasonal variation in dissolved uranium concentration induced by the change of lake water pH in Lake Biwa,Japan

Epilimnion-dominated profiles of dissolved uranium (U) have been observed during summer in an oxygenated Japanese lake, Lake Biwa, contrary to the commonly accepted view that U shows conservative behavior in oxygenated seas and lakes. Monthly observations were conducted to reveal the mechanism for such characteristic distribution and geochemical behavior of dissolved U in the lake. In the surface water, dissolved U concentration started to increase in spring, peaked in summer, and decreased from autumn to winter. In contrast, the concentration remained almost constant in the middle layer (40 m depth) and decreased slightly in the bottom layer (70 m depth) throughout the stagnation period. Mass balance calculations of U suggest that the major mechanism for seasonal variations in the surface layer is the supply of U, not via water inflow from the watershed, but by internal chemical reactions within the lake. A laboratory experiment using the lake water and sediment demonstrated that U was desorbed from and adsorbed onto sediment in response to variations in lake water pH. From these results, it is inferred that the seasonal variation in the concentration of dissolved U in the epilimnion results mainly from the desorptive/adsorptive processes of U between sediment/water interface in response to variation in water pH, which is affected by biological activity in the lake.     

How do we restore New Zealand's biological heritage by 2050?

If we are to make meaningful and measurable progress in restoring New Zealand's biological heritage by 2050, a range of fundamental issues need to be addressed. These relate not just to restoration science but also to building ecosystem resilience in the wider socio‐economic and cultural context within which restoration occurs.     

Intercellular adhesion molecule 1 serves as a primary cognate receptor for the Type IV pilus of nontypeable Haemophilus influenzae

Nontypeable Haemophilus influenzae (NTHI) utilizes the Type IV pilus (Tfp) to adhere to respiratory tract epithelial cells thus colonizing its human host; however, the host cell receptor to which this adhesive protein binds is unknown. From a panel of receptors engaged by Tfp expressed by other bacterial species, we showed that the majority subunit of NTHI Tfp, PilA, bound to intercellular adhesion molecule 1 (ICAM1) and that this interaction was both specific and of high affinity. Further, Tfp‐expressing NTHI inoculated on to polarized respiratory tract epithelial cells that expressed ICAM1 were significantly more adherent compared to Tfp‐deficient NTHI or NTHI inoculated on to epithelial cells to which ICAM1 gene expression was silenced. Moreover, pre‐incubation of epithelial cells with recombinant soluble PilA (rsPilA) blocked adherence of NTHI, an outcome that was abrogated by admixing rsPilA with ICAM1 prior to application on to the target cells. Epithelial cells infected with adenovirus or respiratory syncytial virus showed increased expression of ICAM1; this outcome supported augmented adherence of Tfp‐expressing NTHI. Collectively, these data revealed the cognate receptor for NTHI Tfp as ICAM1 and promote continued development of a Tfp‐targeted vaccine for NTHI‐induced diseases of the airway wherein upper respiratory tract viruses play a key predisposing role.