Dikarboksyylihapot Wikipediassa

http://fi.wikipedia.org/wiki/Dikarboksyylihappo
26.10.2017 teksti tullut Wikipediaan. kaavoja. 

Onko uremisissa neurotoksiineissa myös dikarboksyylimuotoisia?

Kidney Int Suppl. 2001 Feb;78:S77-83.
Endogenous guanidino compounds as uremic neurotoxins.
De Deyn PP, D'Hooge R, Van Bogaert PP, Marescau B.
Source

Department of Neurology, Middelheim Hospital, Wilrijk-Antwerp, Belgium.
Abstract

Epileptic and cognitive symptomatologies are among the most typical manifestations of uremic encephalopathy. Several guanidino compounds (GCs) may play an important role in the etiology of uremic encephalopathy. Four GCs appeared to be highly increased as well in serum, cerebrospinal fluid, and brain of uremic patients, whereas the levels of other metabolically relevant GCs were not or only moderately increased and others were even decreased. These highly increased compounds or "uremic" GCs are creatinine (CTN), guanidine (G), guanidinosuccinic acid (GSA), and methylguanidine (MG). All four compounds were shown to be experimental convulsants in brain concentrations similar to those found in uremic brain. We have described a possible mechanism for the contribution of GCs to uremic hyperexcitability, referring to the in vitro effects of uremic GCs on inhibitory and excitatory amino acid receptors. The excitatory effects of uremic GCs on the central nervous system may be explained by the activation of N-methyl-D-aspartate (NMDA) receptors by GSA, concomitant inhibition of GABA(A) receptors by uremic GCs, and other depolarizing effects. These effects might also indicate the putative contribution of uremic GCs to the etiology of uremic encephalopathy.

PMID:
11168988
[PubMed - indexed for MEDLINE]

• SIIS löytyyhän sieltä meripihkahapon guanidinojohdannainen.

Isovalthine, kaava

Indikaattoriaine?

Hypotyreoosi tiedetään syyksi ihmisellä.
Olisiko vielä b12-vajekin, vai pelkkä aineenvaihdunnallinen vaje?
http://www.guidechem.com/dictionary/2134-55-6.html

Päivitys 2011-11-23

Isovalthine, biosynteesin pohdinta

J Anim Physiol Anim Nutr (Berl). 2005 Feb;89(1-2):1-10. Mammalian isovalthine metabolism.

Rutherfurd-Markwick KJ, Rogers QR, Hendriks WH.

Source

Institute of Food, Nutrition and Human Health, Massey University, Palmerston North, New Zealand. K.J.Rutherfurd@massey.ac.nz

Abstract (Suomennosta)

Isovalthine is a branched-chain sulphur amino acid, which has been found in the urine of normal cats.

ISOVALTIINI on haaraketjullinen rikkiä sisältävä aminohappo, jota kissojen virtsassa on normaalisti.

The concentrations of isovalthine in the urine of healthy adult cats are approximately 24-66 micromol/l and are not affected by the gender of the cat.

Isovaltiinipitoisuus terveen aikuiskissan pissassa on noin 24- 66 mikromoolia litrassa sukupuolesta riippumatta.

Isovalthinuria can be induced in other species (rats, rabbits, guinea-pigs, humans, dogs) following the administration of certain inducing agents such as some hypocholesterolaemic agents, bile acids, hormones or cholesterol precursors.

ISOVALTINURIAA voi indusoitua muissakin lajeissa: rotassa, kaniinissa, hamsterissa, ihmisissä, koirissa- jos niille annetaan joitain tiettyjä aineita kuten eräitä hypokolesterolemisia aineita, sappihappoja, hormoneita tai kolesterolin esiasteita.

The method of induction of isovalthinuria was studied extensively during the 1960s, and efforts were made to understand its biosynthesis.

ISOVALTIININ induktiomenetelmiä tutkittiin laajasti 1960 luvulla, kun koetettiin saada sen biossynteesi selville.

However, although the origin of the sulphur atom in isovalthine was shown to be from cysteine or methionine, the origin of the carbon skeleton remains unknown.

Sen hiiliketjun alkuperä jäi selvittämättä, vaikka saatiinkin selville rikkimolekyylin olevan peräisin cysteiinistä tai metioniinista.

Interest in isovalthine metabolism was generated in part because it was reportedly found in the urine of patients with hypercholesterolaemia.

Asiaan loi mielenkiintoa havainto isovaltiinista hyperkolesterolemisten potilaitten virtsassa.

The validity of this finding however, was brought into question following reports that administration of the drug Bromural (alpha-bromoisovalerylurea), to humans results in the generation of compounds which break down to yield isovalthine following acid hydrolysis.

Havainnon merkitys kuitenkin kyseenalaistettiin, koska Bromural niminen lääkeainekin hajosi yhdistyksiinsä happohydrolyysissa tuottaen isovaltiinia.

This article presents a review and discussion of the experimental data on isovalthine metabolism.

Tässä katsauksessa esitetään ja pohditaan isovaltiinin aineenvaihdunnan kokeellisia tietoja.

PMID:

19112709

[PubMed - indexed for MEDLINE]

(Kts.blogin artikkeli. isovaltiinia esiintyy hypotyreoottisilla henkilöillä virtsassa. )