scholarly journals Interactive comment on “Biotic and abiotic transformation of amino acids in cloud water: Experimental studies and atmospheric implications” by Saly Jaber et al.

2020 ◽  
Author(s):  
Anonymous
2020 ◽  
Author(s):  
Saly Jaber ◽  
Muriel Joly ◽  
Maxence Brissy ◽  
Martin Leremboure ◽  
Amina Khaled ◽  
...  

Abstract. The interest for organic nitrogen and particularly for quantifying and studying the fate of amino acids (AA) has been growing in the atmospheric science community. However very little is known about biotic and abiotic transformation mechanisms of amino acids in clouds. In this work, we measured the biotransformation rates of 18 amino acids with four bacterial strains (Pseudomonas graminis PDD-13b-3, Rhodococcus enclensis PDD-23b-28, Sphingomonas PDD-32b-11 and Pseudomonas syringae PDD-32b-74) isolated from cloud water and representative of this environment. At the same time, we also determined the abiotic (chemical, OH radical) transformation rates within the same solutions mimicking the composition of cloud water. We used a new approach by UPLC-HRMS to quantify free AA directly in the artificial cloud water medium without concentration and derivatization. The experimentally-derived transformation rates were used to compare their relative importance under atmospheric conditions and compared to the chemical loss rates based on kinetic data of amino acid oxidation in the aqueous phase. This analysis shows that previous estimates overestimated the abiotic degradation rates, and thus underestimated the lifetime of amino acids in the atmosphere as they only considered loss processes but did not take into account the potential transformation of amino acids into each other.


2021 ◽  
Vol 18 (3) ◽  
pp. 1067-1080
Author(s):  
Saly Jaber ◽  
Muriel Joly ◽  
Maxence Brissy ◽  
Martin Leremboure ◽  
Amina Khaled ◽  
...  

Abstract. The interest in organic nitrogen and particularly in quantifying and studying the fate of amino acids (AAs) has been growing in the atmospheric-science community. However very little is known about biotic and abiotic transformation mechanisms of amino acids in clouds. In this work, we measured the biotransformation rates of 18 amino acids with four bacterial strains (Pseudomonas graminis PDD-13b-3, Rhodococcus enclensis PDD-23b-28, Sphingomonas sp. PDD-32b-11, and Pseudomonas syringae PDD-32b-74) isolated from cloud water and representative of this environment. At the same time, we also determined the abiotic (chemical, OH radical) transformation rates within the same solutions mimicking the composition of cloud water. We used a new approach by UPLC–HRMS (ultra-performance liquid chromatography–high-resolution mass spectrometry) to quantify free AAs directly in the artificial-cloud-water medium without concentration and derivatization. The experimentally derived transformation rates were used to compare their relative importance under atmospheric conditions with loss rates based on kinetic data of amino acid oxidation in the aqueous phase. This analysis shows that previous estimates overestimated the abiotic degradation rates and thus underestimated the lifetime of amino acids in the atmosphere, as they only considered loss processes but did not take into account the potential transformation of amino acids into each other.


1991 ◽  
Vol 69 (7) ◽  
pp. 1115-1122 ◽  
Author(s):  
Kenneth C. Marshall ◽  
Huangui Xiong

Developments in the field of central neurotransmission indicate that amino acids serve as important and widespread transmitters throughout the central nervous system. There are increasing indications from recent experimental studies that several of the other central neurotransmitters may exert potent effects on central neurons by modulating the actions of amino acids. Noradrenaline and serotonin have received particular attention as potential modulators, and a wide variety of actions has been reported for them. Modulatory actions have been reported at both pre- and post-synaptic levels, including both short- and long-term effects and facilitation or inhibition of amino acid actions. Selectivity has been found both for specific receptor subtypes of the neuromodulator and for specific effects of amino acids. Examples of such selectivity are modification of actions of an amino acid with little effect on spontaneous activity or membrane properties of the target cell, or in comparison to the actions of other neurotransmitters, or even other selective amino acid analogs. Modulatory actions on amino acids have also been reported for several other neurotransmitters including acetylcholine and various peptides. Recent studies of angiotensin II demonstrate that when iontophoretically applied, it can potently and selectively block the depolarizing action of glutamate on locus coeruleus neurons. It is possible that physiological influences of these various transmitter substances are expressed through modification of amino acid actions, rather than through direct effects on central neurons.Key words: neuromodulation, neurotransmitters, glutamic acid, noradrenaline, angiotensin II.


2007 ◽  
Vol 99 (4) ◽  
pp. 855-862 ◽  
Author(s):  
C. Moinard ◽  
I. Nicolis ◽  
N. Neveux ◽  
S. Darquy ◽  
S. Bénazeth ◽  
...  

Previous experimental studies have highlighted that citrulline (CIT) could be a promising pharmaconutrient. However, its pharmacokinetic characteristics and tolerance to loading have not been studied to date. The objective was to characterise the plasma kinetics of CIT in a multiple-dosing study design and to assess the effect of CIT intake on the concentrations of other plasma amino acids (AA). The effects of CIT loading on anabolic hormones were also determined. Eight fasting healthy males underwent four separate oral loading tests (2, 5, 10 or 15 g CIT) in random order. Blood was drawn ten times over an 8 h period for measurement of plasma AA, insulin and growth hormone (Gh). Urine samples were collected before CIT administration and over the next 24 h. None of the subjects experienced side effects whatever the CIT dose. Concerning AA, only CIT, ornithine (ORN) and arginine (ARG) plasma concentrations were affected (maximum concentration 146 (sem 8) to 303 (sem 11) μmol/l (ARG) and 81 (sem 4) to 179 (sem 10) μmol/l (ORN); time to reach maximum concentration 1·17 (sem 0·26) to 2·29 (sem 0·20) h (ARG) and 1·38 (sem 0·25) to 1·79 (sem 0·11) h (ORN) according to CIT dose). Even at high doses, urinary excretion of CIT remained low ( < 5 %). Plasma insulin and Gh were not affected by CIT administration. Short-term CIT administration is safe and well-tolerated. CIT is a potent precursor of ARG. However, at the highest doses, CIT accumulated in plasma while plasma ARG levels increased less than expected. This may be due to saturation of the renal conversion of CIT into ARG.


Author(s):  
Maria Olga Kokornaczyk ◽  
Stephan Baumgartner

Background: The present study makes part of the project ‘Systematic Review of Crystallization Processes Applied for Medical Purposes (SyRCrysMed)’. SyRCrysMed is planned to lead to a publication of three review articles: (i) on crystallization of blood and its derivatives (serum, plasma) for diagnostic purposes, (ii) on crystallization of other biological fluids for diagnostic purposes, and (iii) on crystallization applied to homeopathy (both, basic and clinical research). Medical crystallization is a wide, however fragmented and little known field of science. It embraces different crystallization methodologies and applications. The commune scope of most of the crystallization-based methods is to access a more complex (or different) kind of information on the diagnosed/analyzed subject than it is possible by the use of conventional methods. The underlying thought to this analysis possibility provided by crystallization is that crystallization is an extremely sensitive process and is able to visualize not only the material dimension of the sample (e.g. composition), but also immaterial forces (e.g. force-like effects, sample’s vitality). This sensitivity of crystallization encouraged some researchers (both in the past and nowadays) to apply this process also in homeopathic research. Here we present a first summary of the crystallization-based methodologies with focus on these applied in homeopathy. Materials and methods: 177 articles, books, and book chapters on medical crystallization have been collected from scientific databases, university libraries, and the library at the Goetheanum in Dornach/Switzerland. The collected literature was divided into experimental studies and other literature. All methodologies described in the experimental studies were summarized in accordance to following criteria: type of the biological fluid, dilution degree of the fluid in the crystallizing solution, presence and type of reagent in the crystallizing solution, amount of the crystallizing solution per pattern, type of diagnosed disorder, and sensitivity and specificity of the method. Results: The different diagnostic methodologies concerned mainly the crystallization of blood, plasma, serum and saliva, however also tears, urine, cerebrospinal fluid, vaginal mucosa, and sweat were used. The concentration of the sample in the crystallizing solution ranged from 100% to trace amounts. In case of diluted samples additions of salts, amino acids, neurotransmitters were used. The volume of the crystallization solution per pattern ranged from 3 μl to 6ml. The evaporation took place on a glass surface in forms of droplets, smears, or on round dishes (10cm diameter). The methodologies were applied for the diagnoses of cancer (different types and stages, including pre-symptomatic diagnosis), other diseases (e.g. diabetes, hepatitis B&C, multiple sclerosis, tuberculosis, cystic fibrosis, Sjogren’s syndrome, gastro-intestinal disorders, colon polyps, senile dementia), and physiological stages (fertility days and pregnancy in women, differences before and after physical activity). Finally, the mean sensitivity of the methods amounted to 82.1% (from 40.6% to 100%) and the mean specificity to 84.9% (from 62.3% to 96.7%). In overall the experimental methodologies can be divided into following groups: - Evaporation of droplets of an undiluted biological fluid, - Evaporation of droplets of a diluted biological fluid with addition of salts, - Evaporation of droplets of a diluted biological fluid with addition of salts and amino acids, - Evaporation of droplets containing salts, amino acids and neurotransmitters, - Evaporation of droplets of a watery solution of ashes of a biological fluid (spagyric crystallization), - Evaporation of films/smears of an undiluted biological fluid (ferning tests), - Evaporation of larger amounts of crystallizing solution of a strongly diluted biological fluid with addition of copper chloride placed on dishes (Pfeiffer’s crystallization), Within the analyzed literature there were 10 works on crystallization applied for homeopathy. They concerned three different crystallization approaches, all characterized by a low concentration of the analyzed sample in the crystallization solution (from 1% to trace amounts), or even its absence. These methodologies, besides blood, concerned also plant models and crystallization of the homeopathic preparations by themselves (without a biological sample). In these approaches the crystallization took place with or without the addition of a reagent (salt). Summary & Conclusions: Our preliminary results indicate that crystallization based methods might constitute in future valid, non-invasive, and cost-saving tools enabling, inter alia, pre-symptomatic cancer diagnosis. The studies on crystallization based methods applied to homeopathic research point at a great potential of these methodologies for both basic research and possibly also clinical applications and screening tests. Disclosure Information: The Authors declare that there is no conflict of interest.


2021 ◽  
Author(s):  
Pascal Renard ◽  
Maxence Brissy ◽  
Florent Rossi ◽  
Martin Leremboure ◽  
Saly Jaber ◽  
...  

Author(s):  
Lavanya B

Biosimilars are the biological medicinal products that produce the therapeutic effects in the human body similar to that of inner biological molecule. Biopharmaceuticals consist of nucleic acids, amino acids, polysaccharides, or combination of all compounds. In India, the steps have been taken to manufacture biosimilars with the lowest cost and least side effects. Globally, India is one of the major developing countries in manufacturing and marketing of biosimilars. The application of biosimilar was rapidly growing in treating various disorders such as cancer, inflammatory disease, and cardiovascular diseases. For the approval of biosimilars, in vitro studies become the necessity for representing comparison to a standard biological in terms of quality for experimental studies indicating similar pharmacokinetics, efficacy, safety, and immunogenicity. Huminsulin was the first DNA-recombinant protein accepted by the US Food and Drug Administration (FDA) in 1982. As currently there are no FDA-approved biosimilars for treating breast cancer, many biologic antibodies are under investigation.


2016 ◽  
Vol 48 (11) ◽  
pp. 647-659 ◽  
Author(s):  
Homayoon Bahrami ◽  
Gholamreza Jaferian ◽  
Mehdi D. Davari ◽  
Mansour Zahedi ◽  
Ali Akbar Moosavi-Movahedi

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