The relation between sphingomyelinase activity, lipid peroxide oxidation and NO-releasing in mice liver and brain

We used animal models to study connection between oxidating system and sphingomyelin signaling cascade, because this models are more close related to people disease. Activation of n-sphingomyelinase (n-SMase) in mice liver and brain is coincided in time with increased level of peroxide products (conjugated dienes) after injection of tumor necrosis factor alpha (TNF-alpha). We found that ceramide can induce peroxide oxidation and lead to accumulation of TNF-alpha in animal organs. Nitric oxide (NO) donors (S-nitrosoglutathione and dinitrosyl iron complex) reversibly inhibited activity of n-SMase and decreased level of lipid peroxidation products. This data proposed that both SMase and messengers of oxidative systems could be targets for NO-derived oxidants.     

Electron paramagnetic resonance spectroscopy with N-methyl-D-glucamine dithiocarbamate iron complexes distinguishes nitric oxide and nitroxyl anion in a redox-dependent manner: applications in identifying nitrogen monoxide products from nitric oxide synthase

Though a large number of studies indicate that nitric oxide synthase (NOS) is responsible for NO&z.rad; production in biological systems, controversy still remains concerning whether NOS directly produces NO&z.rad;. Schmidt et al. (PNAS 93:144492, 1996) proposed that NOS first synthesizes nitroxyl anion (NO(-)), which is then converted to NO&z.rad; by superoxide dismutase (SOD). With electron paramagnetic resonance spectroscopy using N-methyl-D-glucamine dithiocarbamate iron (Fe-MGD), we directly detected NO&z.rad; from purified NOS in the absence of SOD (Xia et al., PNAS 94:12705, 1997). We also showed that the requirement for SOD in the previous NO&z.rad; measurements appeared to be due to the high levels of exogenous superoxide production in their reaction system because of the presence of free FAD. However, it was recently questioned whether Fe-MGD can discriminate NO&z.rad; from NO(-) (Komarov et al., FRBM 28:739-742, 2000). In this study we examined the trapping specificity of different redox forms of Fe-MGD. With Fe(2+)-MGD, NO&z.rad; generated characteristic triplet NO&z.rad;-Fe(2+)-MGD signals (g = 2. 04, a(N) = 12.7 G), whereas NO(-) from Angeli's salt was EPR silent. Both NO&z.rad; and NO(-) gave rise to NO&z.rad;-Fe(2+)-MGD signals when Fe(3+)-MGD was used. Strong NO&z.rad; signals were measured from purified nNOS using the NO&z.rad; selective Fe(2+)-MGD and this was not affected by SOD. Thus, spin trapping with Fe-MGD can distinguish NO&z.rad; and NO(-) and this depends on the redox status of the iron. The detection of NO&z.rad; from purified NOS by Fe(2+)-MGD unambiguously reconfirms our previous report that NOS directly synthesizes NO&z.rad; but not NO(-).     

Beneficial effect of gaseous nitric oxide on the healing of skin wounds

Intermittent daily exposures (60 s) to NO-containing gas flow (NO dose of 500 ppm) generated by air-plasma unit "Plason" improves healing of skin wounds in rats. The gas flow treatment shortened the recovery time of both aseptic and purulent wounds (300 mm2 area) by nearly a third. The treatment allows to achieve a marked improvement in the histological, histochemical, and electron-microscopic characteristics of the affected tissue. The mechanism of this phenomenon was studied by spin trapping method. The NO status of the wound tissue was investigated with EPR by following the formation of paramagnetic mononitrosyl complexes with iron-diethyldithiocarbamate, or with the heme groups in hemoglobin or myoglobin. For the first 5 min after a gas treatment with the exposure of 60s, detectable NO levels in the affected tissue were slightly lowered with respect to untreated controls. At subsequent times, treated tissues showed the formation of large quantities of nitroso-iron complexes: At 30-40 min after gas exposure, their levels were nearly two orders of magnitude higher than soon after (15 s-5 min) the exposure. The data demonstrate that the accumulation of nitrosyl-iron complexes reflects a sharp rise in endogenous NO production inside the affected tissue. Paradoxically, the beneficial effect of gaseous NO treatment can be mediated by the formation of limited quantities of peroxynitrite due to the reaction between exogenous NO and superoxide anions generated in high amount in wound tissue. This peroxynitrite has a strong prooxidant effect and can activate various antioxidant systems which diminish the amount of superoxide anions in wound tissue. The reduced superoxide levels allow to increase the contents of endogenous NO in gas-treated tissues. Therefore, the beneficial action of the treatment is attributed to enhanced NO bioavailability.     

Correction of multi-gene deficiency in vivo using a single 'self-cleaving' 2A peptide-based retroviral vector

Attempts to generate reliable and versatile vectors for gene therapy and biomedical research that express multiple genes have met with limited success. Here we used Picornavirus 'self-cleaving' 2A peptides, or 2A-like sequences from other viruses, to generate multicistronic retroviral vectors with efficient translation of four cistrons. Using the T-cell receptor:CD3 complex as a test system, we show that a single 2A peptide-linked retroviral vector can be used to generate all four CD3 proteins (CD3epsilon, gamma, delta, zeta), and restore T-cell development and function in CD3-deficient mice. We also show complete 2A peptide-mediated 'cleavage' and stoichiometric production of two fluorescent proteins using a fluorescence resonance energy transfer-based system in multiple cell types including blood, thymus, spleen, bone marrow and early stem cell progenitors.     

Pacific salmons in the nekton community of the upper epipelagic layer of the Northwest Pacific at Kuril Islands in the early summer of 2012

According to the data of trawl catches performed by the R/V “TINRO” in the upper epipelagic zone (0–50 m) of Pacific waters off the Kuril Islands from June 2 to July 8, 2012, the abundance of nekton was the lowest for the recent 9 years; thus, its density in 2012 (1.5 t/km²) was lower than the average value for the 2004–2012 period (2.40 ± 0.39 t/km²). The major portion of the nekton biomass was formed by pacific salmon (706 000 tons, or 43.6%); their role grows abruptly during pre-spawning migrations of pink salmon, whose proportion reached 29.8% (483 000 t). In 2012, the recorded biomass of pre-anadromous pink salmon was as high as those in the previous 3 years, and even higher than the estimate of 2010 (479 800 t), which is the largest value for even-numbered years. The value of 2012 also was comparable with the estimates for the previous odd-numbered year, 2011, when the total biomass of the species constituted 496 500 t. Chum salmon stands out among other salmon for its record-high biomass (192 700 t, 11.9%), which was twice as high as that in 2011. The biomass and the share of the mesopelagic fish complex was the lowest (286800 t, 17.7%) since 2004. Among other fish species, Kuril groups of walleye pollock also had a substantial biomass (381 200 t, 23.5%). The total biomass of squid (225 300 t, 13.9%) was lower than the value of 2011 (326 300 t, 14.8%) owing to the decline in the biomass of Boreopacific gonate squid by 90 000 t.     

Genome sequencing reveals fine scale diversification and reticulation history during speciation in Sus

Background

Elucidating the process of speciation requires an in-depth understanding of the evolutionary history of the species in question. Studies that rely upon a limited number of genetic loci do not always reveal actual evolutionary history, and often confuse inferences related to phylogeny and speciation. Whole-genome data, however, can overcome this issue by providing a nearly unbiased window into the patterns and processes of speciation. In order to reveal the complexity of the speciation process, we sequenced and analyzed the genomes of 10 wild pigs, representing morphologically or geographically well-defined species and subspecies of the genus Sus from insular and mainland Southeast Asia, and one African common warthog.

Results

Our data highlight the importance of past cyclical climatic fluctuations in facilitating the dispersal and isolation of populations, thus leading to the diversification of suids in one of the most species-rich regions of the world. Moreover, admixture analyses revealed extensive, intra- and inter-specific gene-flow that explains previous conflicting results obtained from a limited number of loci. We show that these multiple episodes of gene-flow resulted from both natural and human-mediated dispersal.

Conclusions

Our results demonstrate the importance of past climatic fluctuations and human mediated translocations in driving and complicating the process of speciation in island Southeast Asia. This case study demonstrates that genomics is a powerful tool to decipher the evolutionary history of a genus, and reveals the complexity of the process of speciation.     

Nitric Oxide Donors as Potential Antitumor Agents

Biophysics - The role of nitric oxide as one of the universal regulators of metabolic processes in living organisms is considered. The results of experimental studies of NO association with cancer...     

Local Knowledge and Conservation of Seagrasses in the Tamil Nadu State of India

Local knowledge systems are not considered in the conservation of fragile seagrass marine ecosystems. In fact, little is known about the utility of seagrasses in local coastal communities. This is intriguing given that some local communities rely on seagrasses to sustain their livelihoods and have relocated their villages to areas with a rich diversity and abundance of seagrasses. The purpose of this study is to assist in conservation efforts regarding seagrasses through identifying Traditional Ecological Knowledge (TEK) from local knowledge systems of seagrasses from 40 coastal communities along the eastern coast of India. We explore the assemblage of scientific and local traditional knowledge concerning the 1. classification of seagrasses (comparing scientific and traditional classification systems), 2. utility of seagrasses, 3. Traditional Ecological Knowledge (TEK) of seagrasses, and 4. current conservation efforts for seagrass ecosystems. Our results indicate that local knowledge systems consist of a complex classification of seagrass diversity that considers the role of seagrasses in the marine ecosystem. This fine-scaled ethno-classification gives rise to five times the number of taxa (10 species = 50 local ethnotaxa), each with a unique role in the ecosystem and utility within coastal communities, including the use of seagrasses for medicine (e.g., treatment of heart conditions, seasickness, etc.), food (nutritious seeds), fertilizer (nutrient rich biomass) and livestock feed (goats and sheep). Local communities are concerned about the loss of seagrass diversity and have considerable local knowledge that is valuable for conservation and restoration plans. This study serves as a case study example of the depth and breadth of local knowledge systems for a particular ecosystem that is in peril.     

Estimation of some molecular effects of gaseous nitrogen oxide on human blood in vitro

The aim of this work is complex estimation of the nitric oxide action on whole blood of healthy people. We tested the reaction of whole human blood (n = 14) to the processing of it with cold NO-containing plasma. We performed direct sparging of blood samples by gaseous flow with NO in a special plant. Cold NO-containing plasma was generated by apparatus “Plazon” (Russia). We tested lactate dehydrogenase activity in direct and reverse reactions, aldehyde dehydrogenase and superoxide dismutase activity, total protein and lactate level, acid-base balance and the partial pressure of gases in blood. For integral assessment of energy metabolism changes a number of derivative parameters (coefficients of energy reaction balance and substrate provision) were used. Our experiments showed that the processing of whole human blood with NO-containing gas flow (NO concentration — 800 ppm) results in significant changes of its physical and chemical parameters. This exposure leads to inhibition of erythrocytes energy metabolism, decreasing plasma antioxidant reserves, developing moderate ionic disorders and acid-base disbalance in blood samples in vitro.