scholarly journals Long-Term Effects of Mercury on Biofilms Grown in Contaminated Microcosms: A Pilot Study

Environments ◽  
2019 ◽  
Vol 6 (3) ◽  
pp. 28
Author(s):  
Perrine Dranguet ◽  
Aline Freiburghaus ◽  
Vera Slaveykova ◽  
Séverine Le Faucheur
Keyword(s):  
Pilot Study ◽  
Surface Coverage ◽  
Dry Weight ◽  
Taxonomic Composition ◽  
Algal Community ◽  
Natural Environments ◽  
Long Term Effects ◽  
Chronic Effects ◽  
Biomonitoring Tool

Biofilms are important components of the mercury (Hg) biogeochemical cycle. However, Hg effects on biofilm communities are overlooked. Here, we present results of a pilot study on the chronic effects of Hg on biofilms, notably on the potential change of their taxonomic composition. Biofilms were cultivated in microcosms enriched with three different Hg concentrations (11 ± 2 pM, 121 ± 9 pM and 1454 ± 54 pM) for 55 days and examined for their accumulated Hg concentrations and composition. Bioaccumulated Hg concentrations were representative of those encountered in natural environments. Despite the lack of influence on the ash free dry weight and chlorophyll content, the surface coverage of the substrata of biofilms grown in Hg decreased. Algal community were strongly affected by Hg, with a decrease in their richness with Ochrophyta found as the most sensitive phyla. The diversity and richness of bacterial communities did not change upon cultivation in Hg but the presence of Proteobacteria increased with Hg, whereas Bacteroidetes, Actinobacteria, Verrumicrobia, and Cyanobacteria were negatively impacted. Overall, the above findings suggest that the examination of the algal community composition might be used as a potential biomonitoring tool to assess the impacts of environmental Hg concentrations on aquatic systems, which would merit further investigation.

Acute, medium and long-term effects of yellow sand and air pollutants on allergy and biomarker search

Impact ◽  
2020 ◽  
Vol 2020 (3) ◽  
pp. 63-65
Author(s):  
Tomomi Higashi
Keyword(s):  
Air Pollutants ◽  
Genetic Factors ◽  
Long Term Effects ◽  
Emergency Rooms ◽  
Improve Treatment ◽  
Treatment And Prevention ◽  
Chronic Effects ◽  
Difficulty Breathing ◽  
Acute And Chronic Effects

Talk to any allergy sufferer and they will tell you how awful it can be. Runny noses, itchy eyes, coughing and difficulties breathing. For many these symptoms rise only to the level of annoyance and can be avoided by steering clear of the source of their allergy. What many people don't realise though is that allergies can become a far more serious issue for a large segment of the population. Shortness of breath and difficulty breathing due to allergies bring many people to emergency rooms and these are just the acute symptoms. Along with the potential for an allergic attack during a windy or dusty day, researchers and medical professionals are beginning to recognise that there are chronic, long term effects associated with allergies. In order to mitigate both the acute and chronic effects of allergies a better understanding of how genetic factors combine with environmental conditions to produce the ranges of symptoms and effects of allergy suffers is needed. Professor Tomomi Higashi, from the Department of Hygiene at Kanazawa University in Japan, is an expert in this field and is currently working to improve treatment and prevention of allergic disease.

Glycyrrhizic acid: the assessment of a no effect level

2000 ◽  
Vol 19 (8) ◽  
pp. 434-439 ◽  
Author(s):  
C E M van Gelderen ◽  
J A Bijlsma ◽  
W van Dokkum ◽  
T J F Savelkoull
Keyword(s):  
Body Weight ◽  
Pilot Study ◽  
Glycyrrhizic Acid ◽  
Mild Hypertension ◽  
Daily Intake ◽  
Long Term Effects ◽  
Healthy Female ◽  
The Usa ◽  
Effect Level

Because from earlier experiments in rats and a pilot study in humans a no effect level of glycyrrhizic acid could not be established, a second experiment was performed in healthy volunteers. The experiment was performed in females only, because the effects were most marked in females in the pilot study. Doses of 0, 1, 2 and 4 mg glycyrrhizic acid/kg body weight were administered orally for 8 weeks to 39 healthy female volunteers aged 19-40 years. The experimentlasted 12 weeks including an adaptation and a “wash-out” period.Ano-effectlevel of2 mg/kgis proposed from the results ofthis study, from which an acceptable daily intake (ADI) of 0.2 mg/kg body weight can be extrapolated with a safety factor of 10. This means consumption of 12 mg glycyrrhizic acid/day for a person with a body weight of 60 kg. This would be equal to 6 g licorice a day, assuming that licorice contains 0.2% of glycyrrhizic acid. The proposed ADI is below the limit advised by the Dutch Nutrition Council of 200 mg glycyrrhizic acid/day. This reflects the relatively mild acute toxicity of glycyrrhizic acid, which is also emphasised by the “generally recognised as safe” (GRAS) status of glycyrrhizic acid in the USA in 1983. However, the long-term effects of a mild chronic intoxication (causing, for example, a mild hypertension), although not immediately lethal, justify special attention to the amount of glycyrrhizic acid used daily.

LONG TERM EFFECTS OF THYROID STIMULATING HORMONE AND INSULIN ON INTRACELLULAR pH IN FRTL-5 CELLS

1992 ◽  
Vol 133 (2) ◽  
pp. R9-R11
Author(s):  
A.M. Wood ◽  
S.P. Bidey ◽  
J. Soden ◽  
W.R. Robertson
Keyword(s):  
Intracellular Ph ◽  
Small Groups ◽  
Thyroid Stimulating Hormone ◽  
Ph Sensitive ◽  
Long Term Effects ◽  
Bicarbonate Ions ◽  
Chronic Effects ◽  
Petri Dishes ◽  
Presence And Absence

ABSTRACT We have studied the chronic effects of TSH (100μU/ml) and insulin (10μg/ml) on intracellular pH (pHi) in FRTL-5 cells using the pH sensitive probe 2′7-bis (2-carboxyethyl-5′-6′) carboxyfluorescein. FRTL-5 cells were cultured on Petri dishes either in the presence of 4H, ie. Coons F-12 containing cortisol (10nM), transferrin (0.5μg/ml), glycyl-histidyl lysine acetate (10ng/ml) and somatostatin (10μg/ml), or with 4H+insulin (5H), 4H+TSH, or 4H+TSH+insulin (6H). pHi was measured in small groups of cells by microspectrofluorimetry both in the presence and absence of bicarbonate ions after cells had been deprived of serum for at least a day. In

Long-term effects of charcoal on nematodes and other soil meso- and microfaunal groups at historical kiln-sites – a pilot study

2019 ◽  
Vol 93 ◽  
pp. 103095 ◽  
Author(s):  
Urs Christian Gießelmann ◽  
Nils Borchard ◽  
Walter Traunspurger ◽  
Klaudia Witte
Keyword(s):  
Pilot Study ◽  
Long Term Effects

Differential Effects of Worry and Imagery After Exposure to a Stressful Stimulus: A Pilot Study

1995 ◽  
Vol 23 (1) ◽  
pp. 45-56 ◽  
Author(s):  
Gillian Butler ◽  
Adrian Wells ◽  
Hilary Dewick
Keyword(s):  
Pilot Study ◽  
Emotional Processing ◽  
Long Term Effects ◽  
Short Term ◽  
Differential Effects ◽  
Short And Long Term ◽  
Intrusive Cognitions ◽  
Stressful Stimulus ◽  
Do So

Imagery appears to be associated with higher levels of anxiety than does worry. Borkovec has argued that worry could be a way of avoiding distressing imagery and the associated affect. Thus worry could suppress emotional activation, interfere with emotional processing, and contribute to the maintenance of anxiety. This hypothesis suggests that short and long-term effects of worrying after experiencing a distressing stimulus should differ from the effects of engaging in imagery. In the short term, imagery should maintain anxiety while worry should not do so, or should do so less. In the longer term, worry should be a less successful way of reducing anxiety associated with the stimulus than imagery, and should be followed by a greater number of intrusive cognitions (indicating the relative failure of emotional processing). These predictions were tested by asking subjects to worry, engage in imagery or “settle down” after watching a distressing video. The results were broadly consistent with the hypothesis. Other interpretations are also considered.

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