Partial Nitritation-Anammox Granules: Short-Term Inhibitory Effects of Seven Metals on Anammox Activity

2017 ◽  
Vol 228 (11) ◽  
Author(s):  
Ángeles Val del Río ◽  
Tulio da Silva ◽  
Tiago Henrique Martins ◽  
Eugenio Foresti ◽  
José Luis Campos ◽  
...  
Keyword(s):  
Inhibitory Effects ◽  
Short Term ◽  
Partial Nitritation ◽  
Anammox Activity

Dexamethasone attenuates the modulatory effect of the insular cortex on the baroreflex in anesthetized rat

2021 ◽  
Author(s):  
Tatiana Sergeevna Tumanova ◽  
Tatiana Nikolaevna Кokurina ◽  
Galina Ivanovna Rybakova ◽  
Viacheslav G. Aleksandrov
Keyword(s):  
Arterial Pressure ◽  
Baroreflex Sensitivity ◽  
Insular Cortex ◽  
Neural Mechanism ◽  
Arterial Baroreflex ◽  
Inhibitory Effects ◽  
Short Term ◽  
Central Autonomic Network

The arterial baroreflex (BR) is an important neural mechanism for the stabilization of arterial pressure (AP). It is known that the insular cortex (IC) and other parts of the central autonomic network (CAN) are able to modulate the BR arc, altering baroreflex sensitivity (BRS). In addition, the sensitivity of the BR changes under the influence of hormones, in particular glucocorticoids (GC). It has been suggested that GC may influence BRS by altering the ability of the IC to modulate the BR. This hypothesis has been tested in experiments on rats anesthetized with urethane. It was found that microelectrostimulation of the visceral area in the left IC causes a short-term drop in AP, which is accompanied by bradycardia, and impairs BRS. The synthetic GC dexamethasone (DEX) did not significantly affect the magnitude of depressor responses but increased BRS and impaired the effect of IC stimulation on the BR. The results obtained confirm the hypothesis put forward and suggest that GC can attenuate the inhibitory effects of the IC on the BR arc, thereby enhancing the sensitivity of the BR.

scholarly journals Resuscitation of starved suspended- and attached-growth anaerobic ammonium oxidizing bacteria with and without acetate

2016 ◽  
Vol 75 (1) ◽  
pp. 115-127 ◽  
Author(s):  
Supaporn Phanwilai ◽  
Chalermraj Wantawin ◽  
Akihiko Terada ◽  
Pongsak (Lek) Noophan ◽  
Junko Munakata-Marr
Keyword(s):  
Nutrient Removal ◽  
Short Term ◽  
Attached Growth ◽  
Copy Numbers ◽  
Anammox Activity ◽  
Suspended Growth

Anammox application for nutrient removal from wastewater is increasing, though questions remain about anammox resilience to fluctuating conditions. Resuscitation of anammox suspended- and attached-growth cultures after 3 months of starvation was studied with and without acetate dosing. Without acetate, the attached-growth culture recovered more quickly than the suspended-growth culture. Suspended-growth cultures recovered more quickly (within 60 days) with weekly and daily acetate dosing than without, but anammox activity and copy numbers decreased with continued acetate addition. All attached-growth cultures recovered within 60 days, but after that activity with acetate dosing was consistently at least 20% lower than that without acetate addition. Ca. Jettenia caeni, Ca. Anammoxoglobus sp., Ca. Brocadia fulgida, Ca. Brocadia anammoxidans, Ca. Brocadia fulgida and Ca. Jettenia asiatica were identified. Acetate addition can significantly accelerate short-term resuscitation of enriched anammox suspended-growth cultures after starvation but may reduce anammox activity over the longer term in suspended- and attached-growth cultures.

The short- and long-term inhibitory effects of Fe (II) on anaerobic ammonium oxidizing (anammox) process

2019 ◽  
Vol 79 (10) ◽  
pp. 1860-1867 ◽  
Author(s):  
Cherh Yih Mak ◽  
Jih Gaw Lin ◽  
Wen Hsing Chen ◽  
Choon Aun Ng ◽  
Mohammed J. K. Bashir
Keyword(s):  
Quantitative Polymerase Chain Reaction ◽  
Substrate Inhibition ◽  
Optimum Concentration ◽  
Anammox Bacteria ◽  
Batch Test ◽  
Short Term ◽  
Anammox Activity ◽  
Study Results ◽  
Anammox Process

Abstract The application of the anammox process has great potential in treating nitrogen-rich wastewater. The presence of Fe (II) is expected to affect the growth and activity of anammox bacteria. Short-term (acute) and long-term effects (chronic) of Fe (II) on anammox activity were investigated. In the short-term study, results demonstrated that the optimum concentration of Fe (II) that could be added to anammox is 0.08 mM, at which specific anammox activity (SAA) improved by 60% compared to the control assay, 0.00 mM. The inhibition concentration, IC50, of Fe (II) was found to be 0.192 mM. Kinetics of anammox specific growth rate were estimated based on results of the batch test and evaluated with Han-Levenspiel's substrate inhibition kinetics model. The optimum concentration and IC50 of Fe (II) predicted by the Han-Levenspiel model was similar to the batch test, with values of 0.07 mM and 0.20 mM, respectively. The long-term effect of Fe (II) on the performance of a sequencing batch reactor (SBR) was evaluated. Results showed that an appropriate Fe (II) addition enhanced anammox activity, achieving 85% NH4+-N and 96% NO2−-N removal efficiency when 0.08 mM of Fe (II) was added. Quantitative polymerase chain reaction (qPCR) was adopted to detect and identify the anammox bacteria.

Gastric leptin: a novel role in cardiovascular regulation

2010 ◽  
Vol 298 (2) ◽  
pp. H406-H414 ◽  
Author(s):  
D. M. Sartor ◽  
A. J. M. Verberne
Keyword(s):  
Cardiovascular Effects ◽  
Receptor Activation ◽  
Cardiovascular Regulation ◽  
Sprague Dawley ◽  
Inhibitory Effects ◽  
Short Term ◽  
Sprague Dawley Rats ◽  
Gut Hormone ◽  
Cervical Vagotomy ◽  
Nerve Discharge

Gastric-derived leptin affects satiety and gastrointestinal function via vagal mechanisms and has been shown to interact with the gut hormone cholecystokinin (CCK). CCK selectively inhibits splanchnic sympathetic nerve discharge (SND) and the activity of a subset of presympathetic vasomotor neurons in the rostroventrolateral medulla (RVLM). The present study sought to examine the effects of gastric leptin on arterial pressure (AP), heart rate (HR), SND, and RVLM neuronal activity to determine whether its effects on cardiovascular regulation are dependent on CCK1 receptors and vagal afferent transmission. To mimic gastric leptin, leptin (15–30 μg/kg) was administered close to the coeliac artery in anesthetized, artificially ventilated Sprague-Dawley rats. Within 5 min, leptin selectively decreased the activity of RVLM neurons also inhibited by CCK (−27 ± 4%; P < 0.001; n = 15); these inhibitory effects were abolished following administration of the CCK1 receptor antagonist lorglumide. Leptin significantly decreased AP and HR (−10 ± 2 mmHg, P < 0.001; and −8 ± 2 beats/min, P < 0.01; n = 35) compared with saline (−1 ± 2 mmHg, 3 ± 2 beats/min; n = 30). In separate experiments, leptin inhibited splanchnic SND compared with saline (−9 ± 2% vs. 2 ± 3%, P < 0.01; n = 8). Bilateral cervical vagotomy abolished the sympathoinhibitory, hypotensive, and bradycardic effects of leptin ( P < 0.05; n = 6). Our results suggest that gastric leptin may exert acute sympathoinhibitory and cardiovascular effects via vagal transmission and CCK1 receptor activation and may play a separate role to adipose leptin in short-term cardiovascular regulation.

scholarly journals Lysozyme and Penicillin Inhibit the Growth of Anaerobic Ammonium-Oxidizing Planctomycetes

2013 ◽  
Vol 79 (24) ◽  
pp. 7763-7769 ◽  
Author(s):  
Ziye Hu ◽  
Theo van Alen ◽  
Mike S. M. Jetten ◽  
Boran Kartal
Keyword(s):  
Cell Wall ◽  
Continuous Cultivation ◽  
Penicillin G ◽  
Anammox Bacteria ◽  
Short Term ◽  
Content Type ◽  
Genome Data ◽  
Wall Structures ◽  
Anammox Activity

ABSTRACTAnaerobic ammonium-oxidizing (anammox) planctomycetes oxidize ammonium in the absence of molecular oxygen with nitrite as the electron acceptor. Although planctomycetes are generally assumed to lack peptidoglycan in their cell walls, recent genome data imply that the anammox bacteria have the genes necessary to synthesize peptidoglycan-like cell wall structures. In this study, we investigated the effects of two antibacterial agents that target the integrity and synthesis of peptidoglycan (lysozyme and penicillin G) on the anammox bacteriumKuenenia stuttgartiensis. The effects of these compounds were determined in both short-term batch incubations and long-term (continuous-cultivation) growth experiments in membrane bioreactors. Lysozyme at 1 g/liter (20 mM EDTA) lysed anammox cells in less than 60 min, whereas penicillin G did not have any observable short-term effects on anammox activity. Penicillin G (0.5, 1, and 5 g/liter) reversibly inhibited the growth of anammox bacteria in continuous-culture experiments. Furthermore, transcriptome analyses of the penicillin G-treated reactor and the control reactor revealed that penicillin G treatment resulted in a 10-fold decrease in the ribosome levels of the cells. One of the cell division proteins (Kustd1438) was downregulated 25-fold. Our results suggested that anammox bacteria contain peptidoglycan-like components in their cell wall that can be targeted by lysozyme and penicillin G-sensitive proteins were involved in their synthesis. Finally, we showed that a continuous membrane reactor system with free-living planktonic cells was a very powerful tool to study the physiology of slow-growing microorganisms under physiological conditions.

scholarly journals Short- and long-term orange dye effects on ammonium oxidizing and anammox bacteria activities

2017 ◽  
Vol 76 (1) ◽  
pp. 79-86 ◽  
Author(s):  
A. Val del Río ◽  
A. Stachurski ◽  
R. Méndez ◽  
J. L. Campos ◽  
J. Surmacz-Górska ◽  
...  
Keyword(s):  
Azo Dye ◽  
Specific Activity ◽  
Dye Adsorption ◽  
Anammox Bacteria ◽  
Ammonia Oxidizing Bacteria ◽  
Continuous Stirred Tank Reactor ◽  
Partial Nitritation ◽  
Anammox Activity ◽  
Anammox Process

The effects of orange azo dye over ammonia oxidizing bacteria (AOB) and anammox bacteria activities were tested. Performed batch tests indicated that concentrations lower than 650 mgorange/L stimulated AOB activity, while anammox bacteria activity was inhibited at concentrations higher than 25 mgorange/L. Long-term performance of a continuous stirred tank reactor (CSTR) for the partial nitritation and a sequencing batch reactor (SBR) for the anammox process was tested in the presence of 50 mgorange/L. In the case of the partial nitritation process, both the biomass concentration and the specific AOB activity increased after 50 days of orange azo dye addition. Regarding the anammox process, specific activity decreased down to 58% after 12 days of operation with continuous feeding of 50 mgorange/L. However, the anammox activity was completely recovered only 54 days after stopping the dye addition in the feeding. Once the biomass was saturated the azo dye adsorption onto the biomass was insignificant in the CSTR for the partial nitritation process fed with 50 mgorange/L. However, in the SBR the absorption was determined as 6.4 mgorange/g volatile suspended solids. No biological decolorization was observed in both processes.

Inhibitory effects of veterinary antibiotics on anammox activity: short- and long-term tests

2017 ◽  
Vol 38 (21) ◽  
pp. 2661-2667 ◽  
Author(s):  
S. Sguanci ◽  
T. Lotti ◽  
C. Caretti ◽  
S. Caffaz ◽  
T. Dockhorn ◽  
...  
Keyword(s):  
Veterinary Antibiotics ◽  
Inhibitory Effects ◽  
Anammox Activity ◽  
Short And Long Term
Sign in / Sign up

Export Citation Format

Share Document