This study investigates how manganese (Mn) stimulates oxidative stress in manganism, a movement disorder caused by high Mn levels resembling Parkinson's disease. The researchers discovered that Mn speeds up the redox cycling of dopathiazines, dopamine derivatives present in the basal ganglia brain region. This redox cycling produces reactive oxygen species and leads to oxidative stress. Mn uniquely stimulated redox cycling of dopathiazines compared to other metals. The effect requires inorganic phosphate and suggests Mn forms a complex with two dopathiazine molecules and phosphate. This Mn-stimulated redox cycling may explain the neurological selectivity of manganism symptoms.
Chemistry of peptide (BPHARM,MPHARM,MSC,BSC)Shikha Popali
THE PRESENTATION DESCRIBING BOND FORMATION OF AMINO ACIDS AND PROTEINS AND COUPLING REAGENTS IN PEPTIDE SYNTHESIS FOLLOWED BY CARBODIMIDES, PHOSPHONIUM AND AMMONIUM SALTS.
Poster reactive extrusion of poly(lactide) with low molecular weight acryl fu...Lionel Derue
Reactive extrusion of poly(lactide) with low molecular weight acryl-functionalized poly(ethylene glycol). An original and effective methodology to toughen poly(lactide)
THE SOLID PHASE PEPTIDE SYNTHESIS IS SLIGHTLY DIFFRENT FROM PEPTIDE SYNTHESIS WHICH IS DISCUSSED HERE, ITS SYNTHESIS WITH STRUCTURE ANS BASICS ARE DISCUSSED WHICH WILL BE VERY USEFUL FOR READERS.
Chemistry of peptide (BPHARM,MPHARM,MSC,BSC)Shikha Popali
THE PRESENTATION DESCRIBING BOND FORMATION OF AMINO ACIDS AND PROTEINS AND COUPLING REAGENTS IN PEPTIDE SYNTHESIS FOLLOWED BY CARBODIMIDES, PHOSPHONIUM AND AMMONIUM SALTS.
Poster reactive extrusion of poly(lactide) with low molecular weight acryl fu...Lionel Derue
Reactive extrusion of poly(lactide) with low molecular weight acryl-functionalized poly(ethylene glycol). An original and effective methodology to toughen poly(lactide)
THE SOLID PHASE PEPTIDE SYNTHESIS IS SLIGHTLY DIFFRENT FROM PEPTIDE SYNTHESIS WHICH IS DISCUSSED HERE, ITS SYNTHESIS WITH STRUCTURE ANS BASICS ARE DISCUSSED WHICH WILL BE VERY USEFUL FOR READERS.
synthesis and characterization of hydrazone ligand and their metal complexesMUBASHIRA M
This slide mainly contain the synthesis, characterization of a few hydrazine based heterocyclic ligand such as hydralazone and phenyl hydralazone and also their metal complexes. so in this work, my aim is to synthesise the ligands; 2-thiophenecarboxylaldehydehydralazone and 2,3-butanedionephenylhydrazone. also to characterized the synthesised hydrazones by different physiochemical techniques.
property of Tris(acetylacetonato)manganese(III) MUKULsethi5
this presentation useful for discussing #chemical and #physical property and application of ..
#Manganese(III)acetylacetonate
#Manganicacetylacetonate
#3-Penten-2-one,4-hydroxy-,manganese(3+) salt
#Mangan(3+)tris[(2Z)-4-oxo-2-penten-2-olat]
#3-Penten-2-one,4-hydroxy-,manganese(3+)salt,(3Z)-(3:1)
in this I discuss chemical and physical property, #spectra, application, #harmness etc
Synthesis and Characterization of New Complexes of 2-(6-Methoxybenzo[d]thiazo...IOSR Journals
Abstract: The synthesis and characterization of manganese (ІІ), cobalt (ІІ), nickel (ІІ), copper (ІІ), zinc (ІІ), cadmium (ІІ) and mercury (ІІ) bidentate 2-(6-methoxybenzo[d]thiazol-2-ylamino)-2-phenyl acetonitrile ligand which was prepared from Benz aldehyde and 6-methoxybenzo[d]thiazol-2-amine in the presence of KCN and acidic medium. The complexes were synthesized by treating an ethanolic solution of the ligand with appropriate amount of metal salts [1:2] [M: L] ratio. The complexes were characterized by using metal and elemental chemical analysis, molar conductance, magnetic susceptibility measurements, FTIR , electronic spectral and mole ratio method. According to the obtained data the probable coordination geometries of manganese (ІІ), cobalt (ІІ), nickel (ІІ), copper (ІІ) zinc (ІІ), cadmium (ІІ) and mercury (ІІ) in these complexes are octahedral. All complexes were found to be non-electrolyte in absolute ethanol, and the complexes were formulated as [ML2Cl2] XH2O. Keywords: 2-(6-methoxybenzo[d]thiazol-2-ylamino)-2-phenyl acetonitrile, N2-donor, transition metals.
Kinetics of Ruthenium(III) Catalyzed and Uncatalyzed Oxidation of Monoethanol...Ratnakaram Venkata Nadh
Kinetics of uncatalyzed and ruthenium(III) catalyzed oxidation of monoethanolamine by N-bromosuccinimide
(NBS) has been studied in an aqueous acetic acid medium in the presence of sodium acetate
and perchloric acid, respectively. In the uncatalyzed oxidation the kinetic orders are: the first order in NBS,
a fractional order in the substrate. The rate of the reaction increased with an increase in the sodium acetate
concentration and decreased with an increase in the perchloric acid concentration. This indicates that free
amine molecules are the reactive species. Addition of halide ions results in a decrease in the kinetic rate,
which is noteworthy. Both in absence and presence of a catalyst, a decrease in the dielectric constant of the
medium decreases the kinetic rate pointing out that these are dipole—dipole reactions. A relatively higher
oxidation state of ruthenium i.e., Ru(V) was found to be the active species in Ru(III) catalyzed reactions. A
suitable mechanism consistent with the observations has been proposed and a rate law has been derived to
explain the kinetic orders.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
BREEDING METHODS FOR DISEASE RESISTANCE.pptxRASHMI M G
Plant breeding for disease resistance is a strategy to reduce crop losses caused by disease. Plants have an innate immune system that allows them to recognize pathogens and provide resistance. However, breeding for long-lasting resistance often involves combining multiple resistance genes
Travis Hills' Endeavors in Minnesota: Fostering Environmental and Economic Pr...Travis Hills MN
Travis Hills of Minnesota developed a method to convert waste into high-value dry fertilizer, significantly enriching soil quality. By providing farmers with a valuable resource derived from waste, Travis Hills helps enhance farm profitability while promoting environmental stewardship. Travis Hills' sustainable practices lead to cost savings and increased revenue for farmers by improving resource efficiency and reducing waste.
ANAMOLOUS SECONDARY GROWTH IN DICOT ROOTS.pptxRASHMI M G
Abnormal or anomalous secondary growth in plants. It defines secondary growth as an increase in plant girth due to vascular cambium or cork cambium. Anomalous secondary growth does not follow the normal pattern of a single vascular cambium producing xylem internally and phloem externally.
Remote Sensing and Computational, Evolutionary, Supercomputing, and Intellige...University of Maribor
Slides from talk:
Aleš Zamuda: Remote Sensing and Computational, Evolutionary, Supercomputing, and Intelligent Systems.
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Inter-Society Networking Panel GRSS/MTT-S/CIS Panel Session: Promoting Connection and Cooperation
https://www.etran.rs/2024/en/home-english/
hematic appreciation test is a psychological assessment tool used to measure an individual's appreciation and understanding of specific themes or topics. This test helps to evaluate an individual's ability to connect different ideas and concepts within a given theme, as well as their overall comprehension and interpretation skills. The results of the test can provide valuable insights into an individual's cognitive abilities, creativity, and critical thinking skills
The use of Nauplii and metanauplii artemia in aquaculture (brine shrimp).pptxMAGOTI ERNEST
Although Artemia has been known to man for centuries, its use as a food for the culture of larval organisms apparently began only in the 1930s, when several investigators found that it made an excellent food for newly hatched fish larvae (Litvinenko et al., 2023). As aquaculture developed in the 1960s and ‘70s, the use of Artemia also became more widespread, due both to its convenience and to its nutritional value for larval organisms (Arenas-Pardo et al., 2024). The fact that Artemia dormant cysts can be stored for long periods in cans, and then used as an off-the-shelf food requiring only 24 h of incubation makes them the most convenient, least labor-intensive, live food available for aquaculture (Sorgeloos & Roubach, 2021). The nutritional value of Artemia, especially for marine organisms, is not constant, but varies both geographically and temporally. During the last decade, however, both the causes of Artemia nutritional variability and methods to improve poorquality Artemia have been identified (Loufi et al., 2024).
Brine shrimp (Artemia spp.) are used in marine aquaculture worldwide. Annually, more than 2,000 metric tons of dry cysts are used for cultivation of fish, crustacean, and shellfish larva. Brine shrimp are important to aquaculture because newly hatched brine shrimp nauplii (larvae) provide a food source for many fish fry (Mozanzadeh et al., 2021). Culture and harvesting of brine shrimp eggs represents another aspect of the aquaculture industry. Nauplii and metanauplii of Artemia, commonly known as brine shrimp, play a crucial role in aquaculture due to their nutritional value and suitability as live feed for many aquatic species, particularly in larval stages (Sorgeloos & Roubach, 2021).
Phenomics assisted breeding in crop improvementIshaGoswami9
As the population is increasing and will reach about 9 billion upto 2050. Also due to climate change, it is difficult to meet the food requirement of such a large population. Facing the challenges presented by resource shortages, climate
change, and increasing global population, crop yield and quality need to be improved in a sustainable way over the coming decades. Genetic improvement by breeding is the best way to increase crop productivity. With the rapid progression of functional
genomics, an increasing number of crop genomes have been sequenced and dozens of genes influencing key agronomic traits have been identified. However, current genome sequence information has not been adequately exploited for understanding
the complex characteristics of multiple gene, owing to a lack of crop phenotypic data. Efficient, automatic, and accurate technologies and platforms that can capture phenotypic data that can
be linked to genomics information for crop improvement at all growth stages have become as important as genotyping. Thus,
high-throughput phenotyping has become the major bottleneck restricting crop breeding. Plant phenomics has been defined as the high-throughput, accurate acquisition and analysis of multi-dimensional phenotypes
during crop growing stages at the organism level, including the cell, tissue, organ, individual plant, plot, and field levels. With the rapid development of novel sensors, imaging technology,
and analysis methods, numerous infrastructure platforms have been developed for phenotyping.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
4. Abstract
Manganism is a condition caused by chronic high levels of Manganese. Interestingly,
this selectively disrupts signaling in the basal ganglia, so Manganism is a movement
disorder resembling Parkinson's Disease. The basal ganglia are a dopamine-rich region
of the brain, and we have discovered that MnCl2 speeds up the redox cycling of
dopamine-derived benzothiazines, called dopathiazines. This redox cycling reduces O2
to superoxide and hydrogen peroxide, so it leads to oxidative stress. This effect is only
seen with Mn and is not reproduced by other metal ions such as Fe, Cu, Zn, Co, Ca or
Mg. The Mn effect requires that inorganic phosphate be present, suggesting that the
phosphate is involved in stabilizing a Mn:dopathiazine complex. It is proposed that
these or similar endogenous dopamine derivatives may magnify Mn-dependent
oxidative stress accounting for the neurological selectivity of manganism.
5. Introduction
Catechols are known to form specific complexes with Mn, and these have been studied
as models for the water-splitting center in photosynthesis (Larsen et al., 1986). Like
dopamine and its derivatives, catechols can bind Mn and lead to redox reactions which are
known to lead to oxidative stress. We examined the effect of manganese on the redox
cycling activity of a numerous dopamine derivatives and catechol analogs to test this
possibility (Figure 1). In addition to suggesting a possible route for these pathological
effects, redox cycling allows us to screen for compounds that react readily with O2 and
interact with manganese.
The dopamine quinone reacts rapidly with thiols like cysteine so when dopamine is
oxidized it yields cysteinyl-dopamine. Both dopamine and cysteinyl-dopamine have
relatively high reduction potentials and oxidize slowly in the presence of O2. Our lab
discovered that reaction of cysteinyl-dopamine and other catechol/thiol adducts with
hypochlorite forms benzothiazine derivatives with redox cycling activities that are greatly
accelerated by Mn. These products, which we call dopathiazines, include DTM2, formed
from dopamine and cysteine, DTM1 (which is formed from dopamine and cysteamine) and
DTM0 (formed by 4-methylcatechol and cysteamine). These dopathiazines have a
characteristic of being sensitive to Mn-stimulation of two-equivalent redox cycling that
separates them from other dopathiazines.
6. Methodology/Experimental
Synthesis of Dopathiazines
Dopathiazines were synthesized by oxidizing a catechol (dopamine) in the
presence of a thiol (cysteine) using ceric ammonium nitrate. The product was
treated with NaOCl in HCl and then purified by chromatography through Dowex
50Wx8 and a C18 reverse phase column (SepPak).
Oxidation
7. Methodology/Experimental
Redox Cycling
Redox cycling occurs when a compound (Q) is repeatedly reduced and the reduced form
is reoxidized by O2. Redox cycling is observed as a decrease in the amount of O2 after the
addition of a reducing agent such as dithiothreitol or ascorbic acid. Redox cycling was
measured as the initial rate of O2 consumption following addition of either 2.5 mM
ascorbic acid or 0.5 mM dithiothreitol. Oxygen concentration was monitored in 4 ml of
buffer solution containing redox cycler and other additions as indicated at 37°C using a
Clark-type oxygen electrode.
8. Figure 1
Figure 1. Manganese stimulates dithiothreitol-driven redox cycling (a) but not
ascorbate-driven redox cycling (b). O2 concentration was recorded at 37°C in 4 ml of
0.2 M potassium phosphate, 1 µM EDTA, pH 7.4 containing DTM2 and MnCl2 as
indicated. Redox cycling was initiated by adding 0.5 mM dithiothreitol or 2.5 mM
ascorbic acid at the arrow.
0
50
100
150
200
250
300
-2 0 2 4 6
[O₂]
(µM) Time (minutes)
12.5 µM Mn
200 nM DTM2
Mn + DTM2
Ascorbate
0
50
100
150
200
250
300
-2 0 2 4 6
[O₂]
(µM)
Time (minutes)
5 µM Mn
800 nM DTM2
Mn + DTM2
Dithiothreitol
9. Figure 2
0
50
100
150
200
No
metal
Mn Fe Cu Co Zn Mg Ca
Rate
(µM
[O₂]/min)
Figure 2. Manganese uniquely stimulates dithiothreitol-driven redox cycling. Redox
cycling by 200 nM DTM2 following addition of 0.5 mM dithiothreitol was recorded as
in Figure 1 in the presence of 10 µM concentrations of MnCl2, FeCl3, CuCl2, CoCl2,
ZnSO4, MgCl2, CaCl2 or no metal (1 µM EDTA). Rates of redox cycling were
determined from the initial slope following dithiothreitol addition. Each bar shows
the average (±SD) of three replicate samples.
10. Figure 3
0
20
40
60
80
100
120
140
160
DTT no
Pi Mn
DTT Pi
Mn
DTT no
Pi
DTT Pi Asc no
Pi
Asc Pi
Rate
(µM/min)
Figure 3. Inorganic phosphate is required for Mn-stimulated redox cycling but not for
ascorbate-driven redox cycling or for dithiothreitol-driven redox cycling in the absence of
Mn. The rate of redox cycling of 1 µM DTM2 was measured in 2 ml of 50 mM Hepes(KOH),
pH 7.4 and 2 ml of either 0.2 M potassium phosphate, 1 µM EDTA, pH 7.4 (Control) or H2O
(no Pi) in the presence or absence of 10 µM MnCl2. Redox cycling was initiated by adding 2.5
mM ascorbic acid or 0.5 mM dithiothreitol. Each bar shows the average (±SD) of three
replicate samples.
11. Figure 4
0
20
40
60
80
0 5 10 15
Rate
(µM
[O₂]/min)
[Mn] (µM)
665 nM DTM2
333 nM DTM2
166 nM DTM2
0 DTM2
a)
0
50
100
0 200 400 600 800
Rate
(µM
[O₂]/min)
[DTM2] (nM)
12.5 uM Mn
5 uM Mn
2.5 uM Mn
1.25 uM Mn
0.5 uM Mn
0 Mn
b)
Figure 4. Dependence of Mn-stimulated redox cycling on concentrations of
Mn and redox cycler. a and b) Rates of redox cycling were measured from
traces as shown in Figure 1a with DTM2 and MnCl2 at the indicated
concentrations. Lines show rates predicted by a kinetic model assuming
formation of a 2:1 complex of DTM2 to MnCl2.
12. Redox Cycling Mechanism
A) Hypothesized
mechanisms of redox
cycling driven by
dithiothreitol and
ascorbic acid. One-
equivalent cycling driven
by ascorbic acid avoids
the slow oxidation of the
fully reduced compound,
which requires either
superoxide or
comproportionation.
B) Mn stimulates two-
equivalent redox cycling
by facilitating oxidation of
the fully reduced
compound in a 2:1
complex.
13. Conclusions
1. Mn stimulates dithiothreitol-driven redox cycling of dopathiazines.
2. The effect on dithiothreitol-driven redox cycling is unique to manganese
and is not reproduced by Fe, Cu, Ca, Zn, Mg, or Co.
3. Inorganic phosphate is required for the Mn effect.
4. The effect of Mn on redox cycling of dopathiazines suggests the formation
of a complex consisting of 1 Mn, 2 dopathiazines and inorganic phosphate
5. The stimulation by Mn of redox cycling of dopathiazines or similar
dopamine derivatives may account for the unique vulnerability of the
dopamine-rich basal ganglia to Mn toxicity.
14. Acknowledgments
We thank Gijong Paik, Christopher Issa, Christopher Jemison, Muhammad
Qureshi, and Dr. Eduardo Palomino for assistance with this work.