Papers and References

In clinical practice a method for assessment of tissue vitality is a sought-after tool. We have developed a new sensor principle, which is able to register changes in tissue concentration of O2 and tissue flow. The technique is based on diffusion of inert gases and mass spectrometer detection of gaseous metabolites. It was hypothesized that the new sensor could register changes in vital parameters after induction and release of an ischaemic insult to muscular tissue. The sensor performance was evaluated in ten anaesthetized pigs subjected to local muscular ischaemia. Preliminary data from this study indicate the validity of registered hypoxia and reduction in tissue flow as a consequence of compromised blood supply. It was concluded that although precise calibration of the technique is not yet established, it holds promise as a technique that can be used to monitor changes in tissue vitality. © IMechE 2005.

In catalyzing the reversible hydration of CO2 to bicarbonate and protons, the ubiquitous enzyme carbonic anhydrase (CA) plays a crucial role in CO2 transport, in acid-base balance, and in linking local acidosis to O2 unloading from hemoglobin. Considering the structural similarity between bicarbonate and nitrite, we hypothesized that CA uses nitrite as a substrate to produce the potent vasodilator nitric oxide (NO) to increase local blood flow to metabolically active tissues. Here we show that CA readily reacts with nitrite to generate NO, particularly at low pH, and that the NO produced in the reaction induces vasodilation in aortic rings. This reaction occurs under normoxic and hypoxic conditions and in various tissues at physiological levels of CA and nitrite. Furthermore, two specific inhibitors of the CO2 hydration, dorzolamide and acetazolamide, increase the CA-catalyzed production of vasoactive NO from nitrite. This enhancing effect may explain the known vasodilating effects of these drugs and indicates that CO2 and nitrite bind differently to the enzyme active site. Kinetic analyses show a higher reaction rate at high pH, suggesting that anionic nitrite participates more effectively in catalysis. Taken together, our results reveal a novel nitrous anhydrase enzymatic activity of CA that would function to link the in vivo main end products of energy metabolism (CO2/H+) to the generation of vasoactive NO. The CA-mediated NO production may be important to the correlation between blood flow and metabolic activity in tissues, as occurring for instance in active areas of the brain. Copyright © 2009 the American Physiological Society.

Five marinades were developed using natural antioxidants. Based on a consumer test of the appearance, three marinades were chosen for further investigation: an oregano, an acerola and a Dijon marinade, the Dijon marinade containing acerola, sumac and oregano. A barbecue and a sumac marinade were not included in the further study. In a home use test, consumers barbecued pork chops with the three marinades. Most of the consumers preferred the oregano and the Dijon marinade, while the acerola marinade was less liked. After controlled cooking using both direct and indirect heat to a core temperature of 65˚C and 80˚C, the content of the heterocyclic aromatic amines (HCA) PhiP, MeIQx, DiMeIQx, Harman and Norharman was analysed. All of the marinades reduced the content of MeIQx and DiMeIQx, although only with indirect heat, while PhiP was reduced using both grilling methods…

Respiration is useful parameter for evaluating embryo quality as it provides important information about metabolic activity. In this paper, we describe a scanning electrochemical microscopy (SECM) technique that is a non-invasive and sensitive method for measuring oxygen consumption by individual embryos. SECM measuring system can non-invasively measure respiration activity by single embryos of several species including human. The bovine embryos with higher oxygen consumption are better candidates to further development into good quality embryos and yielded higher pregnancy rates after embryo transfer. Respiration activity correlates with the embryo quality. SECM technique may be a valuable tool for accurately assessing the quality of embryos and thereby contribute to improving outcomes associated with assisted reproduction, including human in vitro fertilization. © 2007, JAPANESE SOCIETY OF OVA RESEARCH. All rights reserved.

The Fundão mine tailings dam rupture of 2015, in the Rio Doce basin, Brazil, resulted in the deposition of tailings downstream of the dam. It has yet to be determined if metals associated with the tailings have contributed toxicity to organisms, burying a time bomb that could be ticking. Currently the data on toxicity to benthic and aquatic organisms have not been assessed sufficiently to allow an informed assessment using an approach based on weight-of-evidence. This study was conducted to ascertain if sediments at “hot spots” that received Fundão tailings reflected elevated concentrations of metals and if these concentrations were sufficient to result in toxicity to freshwater organisms. The lines-of-evidence considered included assessing metals concentrations in relation to sediment quality criteria, establishing biogeochemical characterizations, completing an evaluation of potential metal release upon resuspension to provide information on bioavailability, and identifying acute and chronic toxicity effects using sensitive native species for waters (water flea, Daphnia similis) and sediments (burrowing midge larvae, Chironomus sancticaroli). Only porewater concentrations of iron and manganese exceeded Brazilian surface water criteria, whereas most trace elements exhibited no enrichment or elevated environmental indexes. The concentrations of bioavailable metals were assessed to be low, and metal concentrations did not increase in the overlying water upon resuspension; rather, they decreased through time. Toxicity testing in resuspended waters and bulk sediments resulted in no acute or chronic toxicity to either benthic or aquatic species. The low metal bioavailability and absence of toxicity of the tailings-enriched sediments was attributed to the strong binding and rapid removal of potentially toxic metal ions caused by oxyhydroxides and particles in the presence of iron-rich particulates. The findings of these sediment hot-spot studies indicate the Fundão dam release of tailings more than six years ago is not causing the current release of toxic concentrations of metals into the freshwaters of the Rio Doce. Integr Environ Assess Manag 2024;20:148–158. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Barley (Hordeum vulgare L.) growth is often inhibited under waterlogged fields. Under waterlogging, a higher C/N ratio in soil easily leads to low oxygen concentration and soil reduction. Although the tolerant varieties for waterlogging and soil reduction were previously reported, those root growth under hypoxia remains unknown. In this study, more than 90% of total leaf area in Deder 2, Hayakiso 2 and Akashinriki remained green even under waterlogged and reduced soil condition at seedling stage. The root elongation of Deder 2 and Hayakiso 2 was similar between aerobic and hypoxic conditions. In comparison, severe leaf necrosis was observed in Haruna Nijo and Houshun. Those root elongation was significantly inhibited under hypoxia, as compared with that under aerobic condition. In conclusion, it was considered that barley varieties tolerant to waterlogged reduced soil showed the better root growth in hypoxia in this study.

This paper reports findings from online, continuous monitoring of dissolved and gaseous nitrous oxide (N2O), combined with dissolved oxygen (DO) and ammonia loading, in a full-scale nitrifying activated sludge plant. The study was conducted over eight weeks, at a 210,000 population equivalent sewage treatment works in the UK. Results showed diurnal variability in the gaseous and dissolved N2O emissions, with hourly averages ranging from 0 to 0.00009 kgN2O-N/h for dissolved and 0.00077-0.0027 kgN2O-N/h for gaseous nitrous oxide emissions respectively, per ammonia loading, depending on the time of day. Similarly, the spatial variability was high, with the highest emissions recorded immediately after the anoxic zone and in the final pass of the aeration lane, where ammonia concentrations were typically below 0.5 mg/L. Emissions were shown to be negatively correlated to dissolved oxygen, which fluctuated between 0.5 and 2.5 mgO2/L, at the control set point of 1.5 mgO2/L. The resulting dynamic DO conditions are known to favour N2O production, both by autotrophic and heterotrophic processes in mixed cultures. Average mass emissions from the lane were greater in the gaseous (0.036% of the influent total nitrogen) than in the dissolved (0.01% of the influent total nitrogen) phase, and followed the same diurnal and spatial patterns. Nitrous oxide emissions corresponded to over 34,000 carbon dioxide equivalents/year, adding 13% to the carbon footprint associated with the energy requirements of the monitored lane. A clearer understanding of emissions obtained from real-time data can help towards finding the right balance between improving operational efficiency and saving energy, without increasing N2O emissions. © 2012 Elsevier Ltd.

Magnetotactic bacteria (MTB) comprise a group of motile microorganisms common in most mesothermal aquatic habitats with pH values around neutrality. However, during the last two decades, a number of MTB from extreme environments have been characterized including: cultured alkaliphilic strains belonging to the Deltaproteobacteria class of the Proteobacteria phylum; uncultured moderately thermophilic strains belonging to the Nitrospirae phylum; cultured and uncultured moderately halophilic or strongly halotolerant bacteria affiliated with the Deltaproteobacteria and Gammaproteobacteria classes and an uncultured psychrophilic species belonging to the Alphaproteobacteria class. Here, we used culture-independent techniques to characterize MTB from an acidic freshwater lagoon in Brazil (pH ∼ 4.4). MTB morphotypes found in this acidic lagoon included cocci, rods, spirilla and vibrioid cells. Magnetite (Fe3O4) was the only mineral identified in magnetosomes of these MTB while magnetite magnetosome crystal morphologies within the different MTB cells included cuboctahedral (present in spirilla), elongated prismatic (present in cocci and vibrios) and bullet-shaped (present in rod-shaped cells). Intracellular pH measurements using fluorescent dyes showed that the cytoplasmic pH was close to neutral in most MTB cells and acidic in some intracellular granules. Based on 16S rRNA gene phylogenetic analyses, some of the retrieved gene sequences belonged to the genus Herbaspirillum within the Betaproteobacteria class of the Proteobacteria phylum. Fluorescent in situ hybridization using a Herbaspirillum-specific probe hybridized with vibrioid MTB in magnetically-enriched samples. Transmission electron microscopy of the Herbaspirillum-like MTB revealed the presence of many intracellular granules and a single chain of elongated prismatic magnetite magnetosomes. Diverse populations of MTB have not seemed to have been described in detail in an acid environment. In addition, this is the first report of an MTB phylogenetically affiliated with Betaproteobacteria class.

Since the earliest days of time, numerous therapeutic plants and medications with plant origins have been utilized extensively. Due to their generally lower side effects, more than half of the population now primarily uses traditional therapies. An Ayurvedic plant belonging to the Boraginaceae family called Onosma Bracteatum Wall is also referred to as Segde in the Middle East and Gaozaban in the Unani medical system. This herb is known by the Arabic names “Lisan-al-Thawr” and “Saquil-ul-Hammam.” “Borage” and “Vipers Bugloss” are the English names for this plant. “Gaozaban” is the name of this herb in Urdu. It is one of the important components of many Unani and Ayurvedic formulas, including Kameera gaozaban sada, Dawa ul misk motadil Jawaardar, Sahi, and the herbal formulation Joshanda, which is used to treat the common cold and influenza. It is safer as compared to self-medication with modern common cold remedies. The phytochemical investigation of the plant revealed the presence of a number of chemical components, including sugars, glycosides such as saponin and anthraquinone glycosides, flavonoids and phenolic compounds, tannins, and gums. Additionally, it contains minerals like potassium, calcium, and others that have pharmacological effects. The seeds, flowers, and leaves are traditionally used as expectorants for bronchitis, stomatitis, wounds, jaundice, constipation, weak heart muscles, rhinitis, and other conditions. This plants has reported various pharmacological actions like antidiarrhoeal, antibacterial, antifungal, antidepressant, anxiolytic, antiaging, wound healing activity, anti-asthamatic , anticancer ,analgesic, antioxidant and lowers the blood pressure and as a memory and as an immunity enhancer. The presence review provides a thorough overview of the research on the medicinal, phytochemical, and traditional uses of Onosma bracteatum Wall. KEYWORDS:

• Background and Aims: Species of Utricularia and Genlisea (Lentibulariaceae) are carnivorous, capturing small prey in traps which are physiologically very active, with abundant quadrifid and bifid glands. Traps of Utricularia have walls composed of two cell layers, and are filled with water. Diverse communities of commensal microorganisms often live inside the traps. Genlisea forms long, hollow subterranean traps of foliar origin, growing in anoxic wet substrate. Knowledge of the O2 concentrations inside Utricularia and Genlisea traps is vital for understanding their physiological functioning and conditions for the life of commensals. To test the hypothesis that prey are killed by anoxia inside the traps, and to measure respiration of traps, [O2] was measured in the fluid in mature traps of these species. • Methods: Oxygen concentration and electrical redox potential were measured using a small Clark-type oxygen sensor and a miniature platinum electrode, respectively, in the fluid of excised and intact traps of six aquatic Utricularia species and in Genlisea hispidula traps. • Key Results: Steady-state [O2] in the traps of both genera always approached zero (median 0.0-4.7 μm). The [O2] decreased after electrodes were inserted into Utricularia traps at a rate which ranged from 0.09 to 1.23 mm h-1 and was lower in traps of irradiated and intact shoots with higher [O2] in shoot tissues. Redox potential ranged from -24 to -105 mV in the traps, confirming the very small or zero [O2]. • Conclusions: Very small or zero [O2], effectively anoxia, is demonstrated in Utricularia and Genlisea traps. This is probably below the critical [O2] for prey survival, and causes captured prey to die of suffocation. Internal trap glands and trap commensals are considered to be adapted to facultative anoxia interrupted by limited periods of higher [O 2] after firings. © The Author 2007. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved.