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Acetylcholine-induced calcium signalling in adrenaline- and noradrenaline-containing adrenal chromaffin cells.

https://arctichealth.org/en/permalink/ahliterature9516
Source
Arch Biochem Biophys. 2004 Apr 1;424(1):23-32
Publication Type
Article
Date
Apr-1-2004
Author
O L Zaika
O M Pochynyuk
P G Kostyuk
E N Yavorskaya
E A Lukyanetz
Author Affiliation
International Center for Molecular Physiology, Kiev, Ukraine.
Source
Arch Biochem Biophys. 2004 Apr 1;424(1):23-32
Date
Apr-1-2004
Language
English
Publication Type
Article
Keywords
Acetylcholine - pharmacology
Adrenal Medulla - cytology
Animals
Atropine - pharmacology
Calcium - chemistry - metabolism
Calcium Signaling - drug effects - physiology
Cholinergic Agonists - pharmacology
Cholinergic Antagonists - pharmacology
Chromaffin Cells - chemistry - drug effects - metabolism - physiology
Cytophotometry - methods
Epinephrine - metabolism
Histocytochemistry - methods
Muscarine - pharmacology
Nicotine - pharmacology
Norepinephrine - metabolism
Rats
Receptors, Muscarinic - metabolism - physiology
Receptors, Nicotinic - metabolism - physiology
Research Support, Non-U.S. Gov't
Tubocurarine - pharmacology
Abstract
Adrenal chromaffin cells secrete catecholamines in response to cholinergic receptor activation by acetylcholine (ACh). Characteristics of Ca(2+) transients induced by activation of nicotinic (nAChRs) and muscarinic (mAChRs) receptors were analyzed using Fura-2 fluorescent measurements on rat chromaffin cells. We first found two populations of chromaffin cells, which differently responded on AChR stimulation. In the first group (n-cells), consecutive ACh applications evoked persistent Ca(2+) transients, whereas desensitizing transients were observed in the other group (m-cells). The AChR agonists and antagonists precisely imitated or abolished the ACh action on n- and m-type cells, respectively. Cytochemical staining showed that n-cells contained adrenaline, whereas m-cells-noradrenaline. Thus, for the first time we found that nAChRs and mAChRs are differentially expressed in adrenergic and noradrenergic chromaffin cells, respectively. Our data suppose that chromaffin cells can be differentially regulated by incoming ACh signals and in such way release different substances-adrenaline and noradrenaline.
PubMed ID
15019833 View in PubMed
Less detail

Dialysate calcium concentration and mineral metabolism in long and long-frequent hemodialysis: a systematic review and meta-analysis for a Canadian Society of Nephrology clinical practice guideline.

https://arctichealth.org/en/permalink/ahliterature114688
Source
Am J Kidney Dis. 2013 Jul;62(1):97-111
Publication Type
Article
Date
Jul-2013
Author
Deborah L Zimmerman
Gihad E Nesrallah
Christopher T Chan
Michael Copland
Paul Komenda
Philip A McFarlane
Azim Gangji
Robert Lindsay
Jennifer MacRae
Robert P Pauly
David N Perkins
Andreas Pierratos
Jean-Philippe Rioux
Andrew Steele
Rita S Suri
Reem A Mustafa
Author Affiliation
Division of Nephrology, Kidney Research Centre of the Ottawa Hospital Research Institute, Division of Nephrology, University of Ottawa, Ottawa, Ontario, Canada. dzimmerman@ottawahospital.on.ca
Source
Am J Kidney Dis. 2013 Jul;62(1):97-111
Date
Jul-2013
Language
English
Publication Type
Article
Keywords
Calcium - chemistry - metabolism
Canada
Hemodialysis Solutions - chemistry - metabolism - standards
Humans
Minerals - metabolism
Nephrology - methods - standards
Practice Guidelines as Topic - standards
Randomized Controlled Trials as Topic - methods - standards
Renal Dialysis - methods - standards
Societies, Medical - standards
Time Factors
Abstract
Patients treated with conventional hemodialysis (HD) develop disorders of mineral metabolism that are associated with increased morbidity and mortality. More frequent and longer HD has been associated with improvement in hyperphosphatemia that may improve outcomes.
Systematic review and meta-analysis to inform the clinical practice guideline on intensive dialysis for the Canadian Society of Nephrology.
Adult patients receiving outpatient long (=5.5 hours/session; 3-4 times per week) or long-frequent (=5.5 hours/session, =5 sessions per week) HD.
We included clinical trials, cohort studies, case series, case reports, and systematic reviews.
Dialysate calcium concentration =1.5 mmol/L and/or phosphate additive.
Fragility fracture, peripheral arterial and coronary artery disease, calcific uremic arteriolopathy, mortality, intradialytic hypotension, parathyroidectomy, extraosseous calcification, markers of mineral metabolism, diet liberalization, phosphate-binder use, and muscle mass.
21 studies were identified: 2 randomized controlled trials, 2 reanalyses of data from the randomized controlled trials, and 17 observational studies. Dialysate calcium concentration =1.5 mmol/L for patients treated with long and long-frequent HD prevents an increase in parathyroid hormone levels and a decline in bone mineral density without causing harm. Both long and long-frequent HD were associated with a reduction in serum phosphate level of 0.42-0.45 mmol/L and a reduction in phosphate-binder use. There was no direct evidence to support the use of a dialysate phosphate additive.
Almost all the available information is related to changes in laboratory values and surrogate outcomes.
Dialysate calcium concentration =1.5 mmol/L for most patients treated with long and long-frequent dialysis prevents an increase in parathyroid hormone levels and decline in bone mineral density without increased risk of calcification. It seems prudent to add phosphate to the dialysate for patients with a low predialysis phosphate level or very low postdialysis phosphate level until more evidence becomes available.
Notes
Comment In: Am J Kidney Dis. 2013 Nov;62(5):1018-924157274
Comment In: Am J Kidney Dis. 2013 Nov;62(5):1019-2024157276
PubMed ID
23591289 View in PubMed
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DNA interaction with biologically active metal ions. Cooperativity of metal ion binding at compacting of DNA.

https://arctichealth.org/en/permalink/ahliterature10834
Source
Acta Biochim Pol. 1998;45(1):107-17
Publication Type
Article
Date
1998
Author
S. Kornilova
E. Hackl
L. Kapinos
V. Andrushchenko
Y. Blagoi
Author Affiliation
B.I. Verkin Institute for Low Temperature Physics and Engineering, National Academy of Sciences of Ukraine, Kharkov.
Source
Acta Biochim Pol. 1998;45(1):107-17
Date
1998
Language
English
Publication Type
Article
Keywords
Calcium - chemistry
Copper - chemistry
DNA - chemistry
Entropy
Manganese - chemistry
Research Support, Non-U.S. Gov't
Spectrophotometry, Infrared
Abstract
The interaction of Cu2+, Mn2+ and Ca2+ ions with DNA in aqueous and water-ethanol solutions at different metal ion concentrations was studied by IR-spectroscopy. At sufficiently high DNA concentrations, DNA interaction with Cu2+, Ca2+ and Mn2+ ions results in compacting of DNA in the aqueous solutions. This process shows a very high cooperativity. In the presence of alcohol, DNA condensation takes place at much lower concentrations of metal ions used than in pure aqueous solution. Binding constants and cooperativity of the metal ion binding rise, and the non-monotonous dependencies of the binding degree, r, on the concentration of free metal ions, Cf, become pronounced. Binding isotherms take the S-like form similar to van der Waals isotherms for phase transitions of the liquid-vapour type. Cu2+ and Ca2+ ion binding to DNA in water-ethanol solutions also results in compacting of DNA macromolecule. The process is characterised by a high positive cooperativity and has a phase transition character.
PubMed ID
9701503 View in PubMed
Less detail

Effect of ethanol on structural transitions of DNA and polyphosphates under Ca2+ ions action in mixed solutions.

https://arctichealth.org/en/permalink/ahliterature10393
Source
Acta Biochim Pol. 2000;47(1):103-12
Publication Type
Article
Date
2000
Author
E V Hackl
Y P Blagoi
Author Affiliation
Institute for Low Temperature Physics and Engineering, National Academy of Sciences of Ukraine, Kharkov, Ukraine. e_hackl@usa.net
Source
Acta Biochim Pol. 2000;47(1):103-12
Date
2000
Language
English
Publication Type
Article
Keywords
Calcium - chemistry
DNA - chemistry - drug effects
Ethanol - pharmacology
Nucleic Acid Conformation
Polyphosphates - chemistry
Solutions
Spectrophotometry, Infrared
Abstract
In the present work using the IR spectroscopy method the effect of ethanol on structural transitions of DNA and polyphosphates under the action of Ca2+ ions in mixed solutions containing ethanol (0-25 vol.%) was studied. It was shown that, on its interaction with Ca2+ ions, in aqueous and mixed solutions DNA becomes transformed into compact form. With the increase of concentration of ethanol the degree of Ca2+-induced DNA compactisation rises. It was found that, in mixed solutions containing ethanol, Ca2+-induced DNA compactisation depends not only on the solution's dielectric permeability but also on the solution structure. On stabilisation of the water structure in the presence of low ethanol concentrations a stabilisation of the DNA macromolecule occurs that leads to the increase of the Ca2+ ion concentration necessary for DNA compactisation. Comparison of the effects of ethanol on Ca2+-induced structural transitions in DNA and polyphosphates in mixed solvents permits to suppose that at alcohol concentrations in solution resulting in disruption of the water spatial structure, some peculiarities are observed in the behavior of those molecules whose hydrophobic interactions are essential.
PubMed ID
10961683 View in PubMed
Less detail

Evidence for sodium-rich alkaline water in the Tagish Lake parent body and implications for amino acid synthesis and racemization.

https://arctichealth.org/en/permalink/ahliterature305962
Source
Proc Natl Acad Sci U S A. 2020 05 26; 117(21):11217-11219
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
05-26-2020
Author
Lee F White
Kimberly T Tait
Brian Langelier
Elizabeth A Lymer
Ana Cernok
Tanya V Kizovski
Chi Ma
Oliver Tschauner
Richard I Nicklin
Author Affiliation
Department of Natural History, Royal Ontario Museum, Toronto, ON M5S 2C6, Canada; lwhite@rom.on.ca.
Source
Proc Natl Acad Sci U S A. 2020 05 26; 117(21):11217-11219
Date
05-26-2020
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Amino Acids - biosynthesis - chemical synthesis
British Columbia
Calcium - chemistry
Ferrosoferric Oxide - chemistry
Hydrogen-Ion Concentration
Lakes
Magnesium - chemistry
Meteoroids
Sodium - chemistry
Stereoisomerism
Tomography - methods
Water - chemistry
Abstract
Understanding the timing and mechanisms of amino acid synthesis and racemization on asteroidal parent bodies is key to demonstrating how amino acids evolved to be mostly left-handed in living organisms on Earth. It has been postulated that racemization can occur rapidly dependent on several factors, including the pH of the aqueous solution. Here, we conduct nanoscale geochemical analysis of a framboidal magnetite grain within the Tagish Lake carbonaceous chondrite to demonstrate that the interlocking crystal arrangement formed within a sodium-rich, alkaline fluid environment. Notably, we report on the discovery of Na-enriched subgrain boundaries and nanometer-scale Ca and Mg layers surrounding individual framboids. These interstitial coatings would yield a surface charge state of zero in more-alkaline fluids and prevent assimilation of the individual framboids into a single grain. This basic solution would support rapid synthesis and racemization rates on the order of years, suggesting that the low abundances of amino acids in Tagish Lake cannot be ascribed to fluid chemistry.
Notes
CommentIn: Proc Natl Acad Sci U S A. 2020 Sep 15;117(37):22650-22651 PMID 32913061
CommentIn: Proc Natl Acad Sci U S A. 2020 Sep 15;117(37):22649 PMID 32913062
PubMed ID
32393617 View in PubMed
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[Role of the Microbial Community in Formation of Speleothem (Moonmilk) in the Snezhnaya Carst Cave (Abkhazia).]

https://arctichealth.org/en/permalink/ahliterature289528
Source
Mikrobiologiia. 2016 Sep; 85(5):598-608
Publication Type
Journal Article
Date
Sep-2016
Source
Mikrobiologiia. 2016 Sep; 85(5):598-608
Date
Sep-2016
Language
Russian
Publication Type
Journal Article
Keywords
Calcium - chemistry
Calcium Carbonate - chemistry
Caves - microbiology
Cold Temperature
Comamonadaceae - growth & development - metabolism
Ferric Compounds - chemistry
Russia
Abstract
The resi Its of investigation of speleothem (moonmilk) from the Snezhnaya cave (West Caucasus, Abkhazia) are-reported. The structure of microbial complexes from moonmilk was investigated by quantita- tive PCR; strains of culturable microorganisms were isolated and their preferred temperature and carbon sources were determined. Among eubacteria, -34% belonged to the iron bacteria (Rhodoferax). Most bacte- rial strains were shown to be facultative psychrophiles with the maximum growth rate at 4C. The microstruc- ture and elemental composition of mionmilk were investigated using a scanning electron microscope (EVO- 40HV, Carl Zeiss) and silicon drifi X-ay detector X-MAX 80 ffM2' The visually plastic and homogeneous mass of moonmilk was shown to be highly heterogeneous, containing various microstructures. The elemental composition of some nanostructures depended on the structure of bacterial biofilms. Some loci of the biofilm were found to contain up to 46% (wt/wt) of iron oxides. Calcium content was high, up to 61.5% (wt/wt) only in cubic crystalline structures which were not involved in microbiological processes.
PubMed ID
29364607 View in PubMed
Less detail

[Role of the Microbial Community in Formation of Speleothem (Moonmilk) in the Snezhnaya Carst Cave (Abkhazia).]

https://arctichealth.org/en/permalink/ahliterature289686
Source
Mikrobiologiia. 2016 Sep; 85(5):598-608
Publication Type
Journal Article
Date
Sep-2016
Source
Mikrobiologiia. 2016 Sep; 85(5):598-608
Date
Sep-2016
Language
Russian
Publication Type
Journal Article
Keywords
Calcium - chemistry
Calcium Carbonate - chemistry
Caves - microbiology
Cold Temperature
Comamonadaceae - growth & development - metabolism
Ferric Compounds - chemistry
Russia
Abstract
The resi Its of investigation of speleothem (moonmilk) from the Snezhnaya cave (West Caucasus, Abkhazia) are-reported. The structure of microbial complexes from moonmilk was investigated by quantita- tive PCR; strains of culturable microorganisms were isolated and their preferred temperature and carbon sources were determined. Among eubacteria, -34% belonged to the iron bacteria (Rhodoferax). Most bacte- rial strains were shown to be facultative psychrophiles with the maximum growth rate at 4C. The microstruc- ture and elemental composition of mionmilk were investigated using a scanning electron microscope (EVO- 40HV, Carl Zeiss) and silicon drifi X-ay detector X-MAX 80 ffM2' The visually plastic and homogeneous mass of moonmilk was shown to be highly heterogeneous, containing various microstructures. The elemental composition of some nanostructures depended on the structure of bacterial biofilms. Some loci of the biofilm were found to contain up to 46% (wt/wt) of iron oxides. Calcium content was high, up to 61.5% (wt/wt) only in cubic crystalline structures which were not involved in microbiological processes.
PubMed ID
29364607 View in PubMed
Less detail

7 records – page 1 of 1.