Hypoxia and anoxia effects on alcohol dehydrogenase activity and hemoglobin content in Chironomus riparius Meigen, 1804

The metabolic effects of low oxygen content on alcohol-dehydrogenase (ADH) activity and hemoglobin (Hb) concentration were investigated in IV-instar larvae of Chironomus riparius (Diptera: Chironomidae) from an Italian stream. Two series of short-term (48 h) experiments were carried out: exposure to (1) progressive hypoxia (95 to 5% of oxygen saturation) and (2) anoxia (at <5% of oxygen saturation). In (1), Hb amount increased with increasing oxygen depletion up to a critical value of oxygenation (about 70% of oxygen saturation). Below this percentage, the Hb amount declined to values comparable with those present in the control. The respiration rate (R) remained almost constant at oxygen saturation >50% and decreased significantly only after 48 h of treatment (= <5% of oxygen saturation) reaching values <100 mmolO2 gAFDW-1 h-1. ADH activity showed two phases of growth, within the first 14 h and over 18 h of exposure. Overall, we inferred that i) Hb might function as short-term oxygen storage, enabling animals to delay the on-set of anaerobiosis; and ii) alcoholic fermentation co-occurs for a short time with aerobic respiration, becoming the prevalent metabolic pathway below 5% of oxygen saturation (<1 mg L-1). These considerations were supported also by results from anoxia exposure (2). In such condition, larvae were visibly stressed, becoming immobile after few minutes of incubation, and ADH reached higher values than in the hypoxia treatment (2.03±0.15 UADH mg prot-1). Overall, this study showed a shift from aerobic to anaerobic activity in C. riparius larvae exposed to poorly oxygenated water with an associated alteration of ADH activity and the Hb amount. Such metabolites might be valid candidate biomarkers for the environmental monitoring of running waters.

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Persistent common arterial trunk with hexaleaflet truncal valve and intact ventricular septum

Interactive CardioVascular and Thoracic Surgery ◽

10.1093/icvts/ivaa205 ◽

2020 ◽

Vol 31 (6) ◽

pp. 915-916

Author(s):

Rodrigo Sandoval Boburg ◽

Julia Kelley Hahn ◽

Michael Hofbeck ◽

Christian Schlensak

Keyword(s):

Oxygen Saturation ◽

Interrupted Aortic Arch ◽

Ventricular Septum ◽

Intact Ventricular Septum ◽

Heart Murmur ◽

Low Oxygen ◽

Short Term ◽

Common Arterial Trunk ◽

Arterial Trunk

Abstract We report a case of a 3-week-old infant who presented a heart murmur and low oxygen saturation. An echocardiography was performed and presented a common arterial trunk type B4 with an interrupted aortic arch and intact ventricular septum. We describe the surgical management and short-term follow-up.

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Short-Term Toxicity of NH3 and Low Oxygen to Benthic Macroinvertebrates of Running Waters and Conclusions for Wet Weather Water Pollution Control Measures

Water Science & Technology ◽

10.2166/wst.1990.0319 ◽

1990 ◽

Vol 22 (10-11) ◽

pp. 291-296 ◽

Cited By ~ 3

Author(s):

Sonja Gammeter ◽

Andreas Frutiger

Keyword(s):

Fish Species ◽

Threshold Concentration ◽

Control Measures ◽

Running Waters ◽

Low Oxygen ◽

Short Term ◽

Weather Situation ◽

Combined Sewer ◽

Receiving Waters ◽

Wet Weather

The short-term toxicity of NH3 and low oxygen was determined for different species of aquatic insects (mayflies and stoneflies). The experiments were carried out in laboratory channels. Compared with fish species, the investigated macroinvertebrates were much less sensitive. Hence, if ecotoxicological criteria for the wet weather situation are developed for ammonia and oxygen, the requirements of sensitive fish species should be considered first. In Switzerland, exceedences of the NH3 short-term threshold concentration caused by combined sewer overflow occur mostly in (too) small receiving waters during summer thunderstorms.

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Arabidopsis phenotyping reveals the importance of alcohol dehydrogenase and pyruvate decarboxylase for aerobic plant growth

Scientific Reports ◽

10.1038/s41598-020-73704-x ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Irene Ventura ◽

Luca Brunello ◽

Sergio Iacopino ◽

Maria Cristina Valeri ◽

Giacomo Novi ◽

...

Keyword(s):

Plant Growth ◽

Alcohol Dehydrogenase ◽

Pyruvate Decarboxylase ◽

Plant Tolerance ◽

Low Oxygen ◽

Short Term ◽

Aerobic Conditions ◽

Fermentative Metabolism ◽

Oxygen Shortage

Abstract Alcohol dehydrogenase (ADH) and pyruvate decarboxylase (PDC) are key to the establishment of the fermentative metabolism in plants during oxygen shortage. Most of the evidence that both ADH and PDC are required for plant tolerance to hypoxia comes from experiments performed by limiting oxygen in the environment, such as by exposing plants to gaseous hypoxia or to waterlogging or submergence. However, recent experiments have shown that hypoxic niches might exist in plants grown in aerobic conditions. Here, we investigated the importance of ADH and PDC for plant growth and development under aerobic conditions, long-term waterlogging and short-term submergence. Data were collected after optimizing the software associated with a commercially-available phenotyping instrument, to circumvent problems in separation of plants and background pixels based on colour features, which is not applicable for low-oxygen stressed plants due to the low colour contrast of leaves with the brownish soil. The results showed that the growth penalty associated with the lack of functional ADH1 or both PDC1 and PDC2 is greater under aerobic conditions than in hypoxia, highlighting the importance of fermentative metabolism in plants grown under normal, aerobic conditions.

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Breathing space: deoxygenation of aquatic environments can drive differential ecological impacts across biological invasion stages

Biological Invasions ◽

10.1007/s10530-021-02542-3 ◽

2021 ◽

Author(s):

James W. E. Dickey ◽

Neil E. Coughlan ◽

Jaimie T. A. Dick ◽

Vincent Médoc ◽

Monica McCard ◽

...

Keyword(s):

Climate Change ◽

Oxygen Saturation ◽

Ecological Impacts ◽

Neogobius Melanostomus ◽

Aquatic Environments ◽

Relative Impact ◽

Low Oxygen ◽

Per Capita ◽

The Impact ◽

Prey Populations

AbstractThe influence of climate change on the ecological impacts of invasive alien species (IAS) remains understudied, with deoxygenation of aquatic environments often-overlooked as a consequence of climate change. Here, we therefore assessed how oxygen saturation affects the ecological impact of a predatory invasive fish, the Ponto-Caspian round goby (Neogobius melanostomus), relative to a co-occurring endangered European native analogue, the bullhead (Cottus gobio) experiencing decline in the presence of the IAS. In individual trials and mesocosms, we assessed the effect of high, medium and low (90%, 60% and 30%) oxygen saturation on: (1) functional responses (FRs) of the IAS and native, i.e. per capita feeding rates; (2) the impact on prey populations exerted; and (3) how combined impacts of both fishes change over invasion stages (Pre-invasion, Arrival, Replacement, Proliferation). Both species showed Type II potentially destabilising FRs, but at low oxygen saturation, the invader had a significantly higher feeding rate than the native. Relative Impact Potential, combining fish per capita effects and population abundances, revealed that low oxygen saturation exacerbates the high relative impact of the invader. The Relative Total Impact Potential (RTIP), modelling both consumer species’ impacts on prey populations in a system, was consistently higher at low oxygen saturation and especially high during invader Proliferation. In the mesocosm experiment, low oxygen lowered RTIP where both species were present, but again the IAS retained high relative impact during Replacement and Proliferation stages at low oxygen. We also found evidence of multiple predator effects, principally antagonism. We highlight the threat posed to native communities by IAS alongside climate-related stressors, but note that solutions may be available to remedy hypoxia and potentially mitigate impacts across invasion stages.

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GENETIC AND BIOCHEMICAL BASIS OF ENZYME ACTIVITY VARIATION IN NATURAL POPULATIONS. I. ALCOHOL DEHYDROGENASE IN DROSOPHILA MELANOGASTER

Genetics ◽

10.1093/genetics/89.2.371 ◽

1978 ◽

Vol 89 (2) ◽

pp. 371-388

Author(s):

John F McDonald ◽

Francisco J Ayala

Keyword(s):

Gene Regulation ◽

Drosophila Melanogaster ◽

Alcohol Dehydrogenase ◽

Natural Populations ◽

Difficult Problem ◽

Regulatory Genes ◽

Biochemical Basis ◽

Evolutionary Consequence ◽

The Third ◽

Adh Activity

ABSTRACT Recent studies by various authors suggest that variation in gene regulation may be common in nature, and might be of great evolutionary consequence; but the ascertainment of variation in gene regulation has proven to be a difficult problem. In this study, we explore this problem by measuring alcohol dehydrogenase (ADH) activity in Drosophila melanogaster strains homozygous for various combinations of given second and third chromosomes sampled from a natural population. The structural locus (Adh) coding for ADH is on the second chromosome. The results show that: (1) there are genes, other than Adh, that affect the levels of ADH activity; (2) at least some of these "regulatory" genes are located on the third chromosome, and thus are not adjacent to the Adh locus; (3) variation exists in natural populations for such regulatory genes; (4) the effect of these regulatory genes varies as they interact with different second chromosomes; (5) third chromosomes with high-activity genes are either partially or completely dominant over chromosomes with low-activity genes; (6) the effects of the regulatory genes are pervasive throughout development; and (7) the third chromosome genes regulate the levels of ADH activity by affecting the number of ADH molecules in the flies. The results are consistent with the view that the evolution of regulatory genes may play an important role in adaptation.

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WALANT–Epinephrine injection may lead to short term, reversible episodes of critical oxygen saturation in the fingertips

Archives of Orthopaedic and Trauma Surgery ◽

10.1007/s00402-020-03744-5 ◽

2021 ◽

Vol 141 (3) ◽

pp. 527-533

Author(s):

P. Moog ◽

M. Dozan ◽

J. Betzl ◽

I. Sukhova ◽

H. Kükrek ◽

...

Keyword(s):

Blood Flow ◽

Oxygen Saturation ◽

Substantial Reduction ◽

Tissue Perfusion ◽

Critical Levels ◽

Short Term ◽

Doppler Flowmetry ◽

Epinephrine Injection ◽

Venous Oxygen Saturation

Abstract Introduction Although the WALANT technique’s long-term safeness has been demonstrated in many studies, there are only few data investigating its short-term effects on tissue perfusion and oxygen levels. It was hypothesized that, temporarily, critical levels of tissue perfusion may occur. Methods Seventeen patients, who were scheduled for different procedures in WALANT technique, were injected with 5–7 ml of 1% Articain containing 1:200,000 epinephrine at the finger base. Capillary-venous oxygen saturation, hemoglobin volume in the capillaries, and relative blood flow in the fingertips were recorded once per second by white light spectrometry and laser Doppler flowmetry before, during and after injection for an average of 32 min. Results Clinically, no persistent tissue malperfusion was observed, and there were no postoperative complications. Capillary-venous oxygen saturation was reduced by ≥ 30% in seven patients. Critical levels of oxygen saturation were detected in four patients during 13 intervals, each lasting for 132.5 s on average. Oxygen saturation returned to noncritical values in all patients by the end of the observation period. Blood flow in the fingertips was reduced by more than 30% in nine patients, but no critical levels were observed, as with the hemoglobin. Three patients demonstrated a reactive increase in blood flow of more than 30% after injection. Conclusions Injection of tumescent local anesthesia containing epinephrine into finger base may temporarily cause a substantial reduction in blood flow and lead to critical levels of oxygen saturation in the fingertips. However, this was fully reversible within minutes and does not cause long-term complications.

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