Studies on the metabolic fate of the14C-labeled methyl group of a methylhydrazine derivative in P815 mouse leukemia

1966 ◽  
Vol 22 (7) ◽  
pp. 431-433 ◽  
Author(s):  
W. Kreis ◽  
Susan B. Piepho ◽  
Hannah V. Bernhard
Keyword(s):  
Metabolic Fate ◽  
Mouse Leukemia ◽  
Methyl Group ◽  
P815 Mouse

Effects of B vitamins and methyl group donors on milk production, milk composition and blood biochemistry in dairy cows

2002 ◽  
Vol 2002 ◽  
pp. 196-196
Author(s):  
S.E Richards ◽  
S Hicklin ◽  
T Lord ◽  
A Nickson ◽  
J Long ◽  
...  
Keyword(s):  
Milk Yield ◽  
Milk Composition ◽  
Metabolic Fate ◽  
Dry Period ◽  
Very Low Density Lipoproteins ◽  
Methyl Group ◽  
Fat Reserves ◽  
Esterified Fatty Acids ◽  
Pregnancy And Lactation ◽  
Tag Accumulation

Recent reviews highlight the importance of the liver in the coordination of nutrient fluxes in support of pregnancy and lactation (e.g. Drackley et al., 2001). Mobilisation of body fat reserves in the late dry period and early lactation leads to an increase in uptake of non-esterified fatty acids (NEFA) by the liver. Their metabolic fate is either oxidation or esterification into triacylglycerides (TAG) that are either exported in very low density lipoproteins (VLDL) or accumulated within liver cells. Recent evidence indicates that TAG accumulation impairs ureagenic and gluconeogenic capacity of the liver, with consequent reductions in feed intake and milk yield, increased incidence of disease and decreased reproductive performance (Overton and Piepenbrink, 1999).LiFTTM (NuTec Ltd.) is a proprietary mixture of B-group vitamins and methyl group donors (rumen protected choline, niacin, vitamin B12, biotin, folic acid and thiamine) designed to reduce the accumulation of TAG in the liver and accelerate VLDL export. The objective of this experiment was to evaluate the effect of LiFT on milk yield and composition and concentrations of metabolites in blood.

scholarly journals METHIONINE METABOLISM IN THE DIGESTIVE TRACT OF SHEEP

1976 ◽  
Vol 56 (4) ◽  
pp. 753-761 ◽  
Author(s):  
M. HIDIROGLOU ◽  
C. G. ZARKADAS
Keyword(s):  
Alimentary Tract ◽  
Insoluble Fraction ◽  
Time Dependent ◽  
Appreciable Amount ◽  
Methionine Metabolism ◽  
Bacterial Protein ◽  
Metabolic Fate ◽  
Hydrogen Atoms ◽  
Methyl Group ◽  
Bacterial Proteins

The metabolic fate and time-dependent incorporation of dietary methionine into rumen bacterial proteins of 1-yr-old wethers has been studied following a single intraruminal administration of L-[rnethyl-14C]-methionine. Of the radioactivity found in the rumen liquor (RL) of sheep 2 h after dosing, an appreciable amount of the [methyl-14C] label was incorporated into methionine of the bacterial protein (15%) and only small amounts (< 1%) as cyst(e)ine. In another experiment, the metabolic fate of methionine labeled either in the sulfur atom or in the carbon or hydrogen atoms of the methyl group was studied in the ruminai, omasal, abomasal and duodenal contents of growing lambs. Two hours after oral administration of the L-[methyl-14C]-, L-[methyl-3H]-, or L-[35S]-rnethionine the portions of the radioactivity of rumen liquor located in the methionine of the rumen bacterial protein were 10.7, 6.9 and 7.3%, respectively while those in the cystine were less than 1% for the methyl-labeled methionine and 4.5% for the 35S methionine. Most of the radioactivity reaching the alimentary tract of growing lambs 2 h after dosing was distributed as labeled methionine in the TCA-insoluble fraction of the digesta in the omasum (86%) and abomasum (65%), whereas only 23% was found in this fraction in the duodenum. The relative amount of radioactivity incorporated into methionine of the bacterial protein from lambs which received L-[methyl-3H]-, or L-[35S]-methionine was appreciably less than that from those which received L-[methyl-14C]-methionine.

scholarly journals Microbial metabolism of pyridinium compounds. Radioisotope studies of the metabolic fate of 4-carboxy-1-methylpyridinium chloride

1972 ◽  
Vol 128 (3) ◽  
pp. 561-568 ◽  
Author(s):  
K. A. Wright ◽  
R. B. Cain
Keyword(s):  
Microbial Metabolism ◽  
Heterocyclic Ring ◽  
Ring Cleavage ◽  
Carboxyl Group ◽  
Metabolic Fate ◽  
Methyl Group ◽  
End Products ◽  
Pyridinium Compounds

Extracts of Achromobacter D formed CO2, methylamine, succinate and formate as metabolic end-products from N-methylisonicotinic acid (4-carboxy-1-methylpyridinium chloride). The origin of the CO2 in the 4-carboxyl group and of the methylamine in the N-methyl group of N-methylisonicotinate was demonstrated with carboxyl-14C- and N-Me-14C-labelled substrates respectively. The carbon skeletons of formate and succinate were shown to arise from the C-2 and the C-3–C-6 atoms of the heterocyclic ring respectively by using N-methyl[2,3-14C2]isonicotinate. This result is consistent with ring cleavage by the organism between C-2 and C-3.

Use of [13C-methyl]Tropinone to follow the fate of the methyl group during calystegine formation in root cultures of Solanum dulcamara (Solanaceae)

Planta Medica ◽  
2008 ◽  
Vol 74 (09) ◽  
Author(s):  
TA Bartholomeusz ◽  
R Molinié ◽  
A Roscher ◽  
AC Freydank ◽  
B Dräger ◽  
...  
Keyword(s):  
Root Cultures ◽  
Solanum Dulcamara ◽  
Methyl Group

STEROIDSTRUKTUR UND LEBERTOXIZITÄT

1967 ◽  
Vol 54 (1) ◽  
pp. 73-84 ◽  
Author(s):  
H. L. Krüskemper ◽  
G. Noell
Keyword(s):  
Alkaline Phosphatase ◽  
Liver Function ◽  
Blood Coagulation ◽  
Electrophoretic Pattern ◽  
Coagulation Factors ◽  
Blood Coagulation Factors ◽  
Methyl Group ◽  
Liver Functions ◽  
Male Subjects ◽  
Androstane Derivatives

ABSTRACT In male subjects investigations have been carried out regarding the effect of C1- and C17-methylated androstane derivatives (20 mg per day, orally, two weeks) on liver functions (parameters: activities of GPT, GOT, alkaline phosphatase and cholinesterase in serum; electrophoretic pattern; blood coagulation factors V, VII, X and prothrombin; BSP-retention). In addition to the well known hepatotropic action of 17α-alkylated C-19-steroids a quasi-axial 1α-methyl configuration (in 1α-methylandrost-2-en-17β-ol) definitely increased BSP-retention and several coagulation factors. These steroid effects decreased gradually when a methyl group was introduced in C1 equatorially (1-methylandrost-1-en-17β-ol-3-one) or quasi-equatorially (1β-methylandrost-2-en-17β-ol), the latter compound completely lacking from any influence on parameters of liver function under investigation.

A Reinvestigation of the Deceptively Simple Reaction of Toluene with ●OH, and the Fate of the Benzyl Radical. I. a Combined Thermodynamic and Kinetic Study on the Competition Between ●OH Addition and Hydrogen Abstraction Reactions.

2019 ◽  
Author(s):  
Zoi Salta ◽  
Agnie M. Kosmas ◽  
Marc E. Segovia ◽  
Martina Kieninger ◽  
Oscar Ventura ◽  
...  
Keyword(s):  
Density Functional ◽  
Room Temperature ◽  
Hydrogen Abstraction ◽  
Reaction Rates ◽  
Composite Model ◽  
Alternative Mechanism ◽  
Radical Intermediate ◽  
Experimental Conditions ◽  
Methyl Group ◽  
Benzyl Radical

This work reports density functional and composite model chemistry calculations performed on the reactions of toluene with the hydroxyl radical. Both experimentally observed H-abstraction from the methyl group and possible additions to the phenyl ring were investigated. Reaction enthalpies and heights of the barriers suggest that H-abstraction is more favorable than ●OH addition to the ring. The calculated reaction rates at room temperature and the radical-intermediate product fractions support this view. This is somehow contradictory with the fact that, under most experimental conditions, cresols are observed in a larger concentration than benzaldehyde. Since the accepted mechanism for benzaldehyde formation involves H-abstraction, a contradiction arises that begs for an explanation. In this first part of our work we give the evidences that support the preference of hydrogen abstraction over ●OH addition and suggest an alternative mechanism which shows that cresols can actually arise also from the former reaction and not only from the latter.

A Reinvestigation of the Deceptively Simple Reaction of Toluene with ●OH, and the Fate of the Benzyl Radical. I. a Combined Thermodynamic and Kinetic Study on the Competition Between ●OH Addition and Hydrogen Abstraction Reactions.

2019 ◽  
Author(s):  
Zoi Salta ◽  
Agnie M. Kosmas ◽  
Marc E. Segovia ◽  
Martina Kieninger ◽  
Oscar Ventura ◽  
...  
Keyword(s):  
Density Functional ◽  
Room Temperature ◽  
Hydrogen Abstraction ◽  
Reaction Rates ◽  
Composite Model ◽  
Alternative Mechanism ◽  
Radical Intermediate ◽  
Experimental Conditions ◽  
Methyl Group ◽  
Benzyl Radical

This work reports density functional and composite model chemistry calculations performed on the reactions of toluene with the hydroxyl radical. Both experimentally observed H-abstraction from the methyl group and possible additions to the phenyl ring were investigated. Reaction enthalpies and heights of the barriers suggest that H-abstraction is more favorable than ●OH addition to the ring. The calculated reaction rates at room temperature and the radical-intermediate product fractions support this view. This is somehow contradictory with the fact that, under most experimental conditions, cresols are observed in a larger concentration than benzaldehyde. Since the accepted mechanism for benzaldehyde formation involves H-abstraction, a contradiction arises that begs for an explanation. In this first part of our work we give the evidences that support the preference of hydrogen abstraction over ●OH addition and suggest an alternative mechanism which shows that cresols can actually arise also from the former reaction and not only from the latter.

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