scholarly journals Stress response ofChironomus ripariusto changes in water temperature and oxygen concentration in a lowland stream

2018 ◽  
Author(s):  
Alessandro Manfrin ◽  
Stefano Larsen ◽  
Massimiliano Scalici ◽  
Sven Wuertz ◽  
Michael T. Monaghan
Keyword(s):  
Water Temperature ◽  
Oxygen Concentration ◽  
Ecological Status ◽  
Model Organisms ◽  
Suitable Model ◽  
Low Oxygen ◽  
Short Term ◽  
Root Effect ◽  
Hsp70 Mrna ◽  
Lowland Stream

AbstractThe increasing impairment of lotic ecosystems has promoted a growing effort into assessing their ecological status by means of biological indicators. While community-based approaches have proven valuable to assess ecosystem integrity, they mostly reflect long-term changes and might not be suitable for tracking and monitoring short-term events. Responses to rapid changes in environmental conditions have been rarely studied under natural conditions. Biomarkers offer the benefit of integrating biological responses at different time scales. Here we used a field experiment to test how the synthesis of heat shock protein 70 (HSP70) and Haemoglobin (Hb) in laboratory-reared larvae ofChironomus riparius(Diptera, Chironomidae) were influenced by short-term changes to water temperature and oxygen concentration in a lowland stream. Our aim was to determine whether HSP70 mRNA expression and Hb content could be used as anin situ“early warning system” for freshwater habitats undergoing environmental change. HSP70 exhibited a clear response to changes in temperature measured over a one-day period, confirming its suitability as an indicator of environmental stress. Hb concentration was related to oxygen concentration, but not to temperature. Our findings support the hypothesis that depletion in oxygen induces Hb synthesis inC. ripariuslarvae. Because tolerance to low oxygen is not only related to total Hb, but also to a more efficient uptake (binding to Hb, e.g. Bohr effect) and release of oxygen to the cell (Root effect), we cannot discern from our data whether increased efficiency played a role. We suggest thatC. ripariusis a suitable model organism for monitoring sub-lethal stress in the field and that the approach could be applied to other species as more genomic data are available for non-model organisms.

scholarly journals Stress response of Chironomus riparius to changes in water temperature and oxygen concentration in a lowland stream

2018 ◽  
Vol 95 ◽  
pp. 720-725 ◽  
Author(s):  
Alessandro Manfrin ◽  
Stefano Larsen ◽  
Massimiliano Scalici ◽  
Sven Wuertz ◽  
Michael T. Monaghan
Keyword(s):  
Stress Response ◽  
Water Temperature ◽  
Oxygen Concentration ◽  
Chironomus Riparius ◽  
Lowland Stream

Effect of low oxygen concentration on activation of inflammation by Helicobacter pylori

2021 ◽  
Vol 560 ◽  
pp. 179-185
Author(s):  
Adiza Abass ◽  
Tokuju Okano ◽  
Kotchakorn Boonyaleka ◽  
Ryo Kinoshita-Daitoku ◽  
Shoji Yamaoka ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Oxygen Concentration ◽  
Low Oxygen ◽  
Low Oxygen Concentration

The Constant Low Oxygen Concentration in All the Target Cells for Mouse Tail Radionecrosis

1982 ◽  
Vol 92 (1) ◽  
pp. 172 ◽  
Author(s):  
J. H. Hendry ◽  
J. V. Moore ◽  
B. W. Hodgson ◽  
J. P. Keene
Keyword(s):  
Oxygen Concentration ◽  
Target Cells ◽  
Low Oxygen ◽  
Low Oxygen Concentration

Oxygen concentration in milk of healthy and mastitic cows and implications of low oxygen tension for the killing ofStaphylococcus aureusby bovine neutrophils

1988 ◽  
Vol 55 (4) ◽  
pp. 513-519 ◽  
Author(s):  
Susan J. Mayer ◽  
Avril E. Waterman ◽  
Peter M. Keen ◽  
Neil Craven ◽  
F. John Bourne
Keyword(s):  
Staphylococcus Aureus ◽  
Mammary Gland ◽  
Partial Pressure ◽  
Oxygen Concentration ◽  
Bactericidal Activity ◽  
Mammary Glands ◽  
Low Oxygen ◽  
Low Oxygen Tension ◽  
Bovine Neutrophils ◽  
Venous Plasma

SummaryThe partial pressure of O2in milk from normal cows and from cows with mastitis was measured and the concentrations of O2calculated. Oxygen levels of milk from normal cows were similar to those in venous plasma, but inflammation of the mammary gland led to a dramatic drop in O2concentration to < 10% of control values. Intracellular survival ofStaphylococcus aureusstrain M60 in bovine neutrophils was greater under anaerobic than aerobic conditions. The implications of low O2concentrations in milk from infected mammary glands for the bactericidal activity of bovine neutrophils is discussed.

scholarly journals Zooplankton fluctuations in Jurumirim Reservoir (São Paulo, Brazil): a three-year study

2009 ◽  
Vol 69 (1) ◽  
pp. 1-18 ◽  
Author(s):  
LP. Sartori ◽  
MG. Nogueira ◽  
R. Henry ◽  
EM. Moretto
Keyword(s):  
Water Column ◽  
Oxygen Concentration ◽  
Retention Time ◽  
Sao Paulo ◽  
Seasonal Effect ◽  
São Paulo ◽  
Low Oxygen ◽  
High Concentration ◽  
Heterogeneous Distribution ◽  
Low Oxygen Concentration

During three consecutive years, monthly samples of zooplankton were taken in the lacustrine (dam) zone of Jurumirim (São Paulo, Brazil). The seasonal effect on basic limnological features (thermal regime, oxygen distribution, phytoplankton biomass, etc.) was also examined. The influence of the seasonality on the fluctuation of the zooplankton composition and abundance was not clearly detected (low degree of recurrent patterns). Rotifers (32 taxa) were the most abundant organisms during almost the entire study period with some seasonal alternations in the maximum abundance peaks of the main taxa (Conochilus unicornis, Keratella americana, K. cochlearis and Hexarthra spp.), except for Polyarthra (mainly P. vulgaris). Only occasionally copepods were numerically dominant. Higher copepod abundance was positively associated to periods of increase in the water retention time. Among the Copepoda (10 taxa) the calanoids (mainly Notodiaptomus iheringi) were more abundant, especially in warmer periods. Conversely, cyclopoids had higher abundance in autumn and winter. The species Thermocyclops minutus and T. decipiens co-occurred, but the first attained higher abundance. Some evidence of co-existence strategies between both species are considered. Cladocera (17 taxa) was never numerically dominant and the main taxa (Bosmina spp., Ceriodaphnia spp. and Diaphanosoma spp.) occurred almost the whole study period and did not present a seasonal pattern of fluctuation. Diaphanosoma (mainly D. birgei) attained the highest abundance among cladocerans. Most organisms were always found at the surface, but they also occupy the whole water column, even in periods of stratified conditions and low oxygen concentration in the bottom layers. Among the main zooplanktonic taxa, only Hexarthra avoids deep layers. An exceptionally high concentration of Copepoda nauplii on the surface was influenced by low transparency, high concentration of phytoplankton at this layer and low oxygen concentration at the bottom. In periods of higher retention timevariability there was a more heterogeneous distribution of the zooplankton in the water column. The increase in the retention time seems also to favor the copepod development. Finally, some inter-decade changes are considered on the basis of zooplankton assemblage structure observations.

Sign in / Sign up

Export Citation Format

Share Document