(Wikipediasta)
Adstringentti eli astringentti on kemiallinen aine, jota käytettäessä elimistön kudokset supistuvat tai kuroutuvat (jumoutuvat). Sana "adstringentti" juontuu latinan kielen sanasta astringere ("liittää yhteen"). Tavallisimpia jumeita ovat galmeija ja amerikantaikapähkinä.
Lääketieteessä jumoamista käytetään yleensä tooppisiin hoitoihin.
Adstringaatioksi kutsutaan myös suuhun syntyvää kuivaa jumon tunnetta, jonka aiheuttavat tanniinit. Näitä esiintyy esimerkiksi oratuomen ja tuomen marjoissa sekä kakin hedelmissä. Tanniinit tuhoavat syljen proteiineja, mikä aiheuttaa "hiekkapaperimaisen" tunteen suussa. Monet nisäkkäät (myös ihminen) kokevat jumoavan maun yleensä epämiellyttävänä. Tämän takia ne välttävät adstringoivien hedelmien syömistä. Toisaalta linnut eivät kykene maistamaan adstringaatiota, ja syövätkin mielellään tällaisiakin marjoja.
Adstringentteja esiintyy myös viineissä ja teessä. Joissakin viinilaaduissa, erityisesti rypäleistä valmistetuissa nuorissa punaviineissä kuten Cabernet Sauvignon'ssa pientä määrää adstringentteja pidetään asiaan kuuluvana.
Adstringoivat lääkkeet aiheuttavat limakalvojen tooppisten kudosten supistumista. Niitä käytetään usein sisäisesti estämään veriseerumin tai liman erittymistä esimerkiksi kurkkukivun, verenvuotojen, ripulin tai mahahaavan yhteydessä. Ulkoisesti käytettävät jumelääkkeet koaguloivat vähäisessä määrin ihon proteiineja. Tämän takia ne kuivattavat, lujittavat ja suojaavat ihoa. Aknesta kärsiviä ohjataan usein käyttämään jumeita, jos iho on myös rasvoittuva
Yleisesti käytettyjä adstringentteja ovat aluna, kaurapuuro, siankärsämö, pimenttiöljy, hyvin kylmä vesi ja alkoholi. Monet jumevalmisteet sisältävät hopeanitraattia, sinkkioksidia, sinkkisulfaattia, alumiiniasetaatin vesiliuosta, bentsoiinitinktuuraa ja kasvisperäisiä aineita kuten parkkihappoa ja gallushappoa. Granaattiomenan punaiset, ruusumaiset kukat ovat maultaan hyvin kitkeriä. Lääketieteessä niitä on kuivattuina käytetty jumeeksi Myös joidenkin metallien suoloja ja happoja on käytetty adstringaatioon.
Tässä blogissani on seikkoja terveellisistä ravintotekijöistä ja kehon luonnollisesta puolustuksesta, jota voi tukea terveellisen ravitsemuksen ja terveellisten elämäntapojen avulla.
tisdag 29 oktober 2013
fredag 11 oktober 2013
Luteiini, E 161b, silmän verkkokalvolle tärkeä aine
SILMÄN KELTAISELLE TÄPLÄLLE tärkeä on luteiini: Tässä kohdassa mainitaan muitakin luteiinipitoisia ravinteita. http://en.wikipedia.org/wiki/Lutein |
---|
Product |
Lutein/zeaxanthin (micrograms per hundred grams) |
---|---|
nasturtium (yellow flowers, lutein levels only) | 45,000 |
kale (raw) | 39,550 |
kale (cooked) | 18,246 |
dandelion leaves (raw) | 13,610 |
nasturtium (leaves, lutein levels only) | 13,600 |
turnip greens (raw) | 12,825 |
spinach (raw) | 12,198 |
spinach (cooked) | 11,308 |
swiss chard (raw or cooked) | 11,000 |
turnip greens (cooked) | 8440 |
collard greens (cooked) | 7694 |
watercress (raw) | 5767 |
garden peas (raw) | 2593 |
romaine lettuce | 2312 |
zucchini | 2125 |
brussels sprouts | 1590 |
pistachio nuts | 1205 |
broccoli | 1121 |
carrot (cooked) | 687 |
Maize/corn | 642 |
egg (hard boiled) | 353 |
carrot (raw) | 256 |
kiwifruit | 122 |
lördag 27 april 2013
Pii, Silica, siliconum (Si)
The
EFSA Journal (2009) 1132, 1-24© European Food Safety Authority, 2009
Suomennosta
lähteestä
Pii-kalkki eli kalsiumsilikaatti ja
piidioksidi/ piihappogeeli lisättyinä elintarvikkeisiin
lisäaineitten (E) joukkoon . Ravinnon lisäaineita käsitelevän
asiantuntijapanelin tieteellinen mielipide
Calcium silicate and silicon dioxide/silicic acid gel added for nutritional purposes to food supplements 1 Scientific Opinion of the Panel on Food Additives and Nutrient Sources added to Food
(Questions
No EFSA-Q-2005- 140, EFSA-Q-2006-220, EFSA-Q-2005-098,
EFSA-Q-2005-099)
Adopted on 5 June 2009
PANEL M EMBERS
F.
Aguilar, U.R. Charrondiere, B. Dusemund, P. Galtier, J. Gilbert,
D.M. Gott, S. Grilli, R.
Guertler,
G.E.N. Kass, J. Koenig, C. Lambré, J-C. Larsen, J-C. Leblanc, A.
Mortensen, D.
Parent-Massin,
I. Pratt, I.M.C.M. Rietjens, I.Stankovic, P. Tobback, T. Verguieva,
R.A.
Woutersen.
Yhteenveto (SUMMARY)
Kun EU
komissiolta oli tullut pyyntö Euroopan
Elintrviketurvallisuusvirastolle (EFSA) , kysyttiin
asiantuntijapanelin mielipidettä kalsiumsilikaatista,
silikonioksidista ja silisiinihappogelistä ja niiden
lisäämisestä elintarvikelisäaineitten joukkoon. Tässä
esitetty ielipide koskee ainoastaan kalsiumsilikaattia, piioksidia
ja piihappogeeliä pii-lähteinä, niiden turvallisuutta ja piin
(Si) biologista saatavuutta näistä lähteistä. Paneli noteeraa,
että yksi anojista oli hakemassa myös lupaa kalsiumsilikaatin
käytölle kalsiumlähteenä.
llowing
a request from the European Commission to the European Food Safety
Authority,
the
Scientific Panel on Food Additives and Nutrient Sources added to
Food has been asked to
deliver
a scientific opinion on calcium silicate, silicon dioxide and
silicic acid gel added for
nutritional
purposes to food supplements. The present opinion deals only with
the safety of calcium silicate, silicon dioxide, silicic acid gel as
sources of silicon, and with the bioavailability of silicon from
these sources. The Panel notes that one petitioner also applied for
the use of calcium silicate as a source of calcium.
Tähän
panelikäsittelyyn ei sisällytetä tällä kerralla piin ja
kalsiumin omaa turvallisututa, siis niitä määriä mitä saatetaan
konsumoida, eikä pohdita piin merkitystä ravintoaineena.
The
safety of silicon and calcium itself, in terms of amounts that may
be consumed, and the
consideration
of silicon as a nutrient, are outside the remit of this Panel.
Pii-
alkuainetta , Silicon (Si, siliconum) esiintyy elintarvikkeissa
piidioksidina (SiO2, silikonidioksidi) ja piisuoloina,
silikaatteina. Runsaita piipitoisuuksia on havaittavissa
kasviperäisissä elintarvikkeissa ja erityisesti viljoissa, kun
taas animaalisissa ravintolähteissä silikonin pitoisuus on
matalampaa..
Silicon
occurs naturally in foods as silicon dioxide (SiO2,
silica) and silicates. High levels of
silicon
are found in foods derived from plants, and particularly cereals,
whereas silicon levels
are
lower in foods from animal sources.
Ortopiihappo
( http://fi.wikipedia.org/wiki/Piihappo)
on pääasiallinen piilaatu, mitä esiintyy juomavedessä ja muissa
nesteissä, kuten oluessa ja se on kaikkein helpoin piin saantilähde
ihmiselle. Suunkautta otettuna juuri tämä piihappomuoto ( orto-
piihappo) on pääasiallisin kemiallinen laji, mistä piitä
imeytyy ihmiseen.
Orthosilicic
acid [Si(OH)4] is the
major silicon species present in drinking water and other
liquids,
including beer, and is the most readily available source of silicon
to man. After oral
consumption,
the main chemical species by which silicon is absorbed is
orthosilicic acid. 1
Sitaattitarkoituksiin
seuraava osoite:
For
citation purposes:
Scientific
Opinion of the Panel on Food Additives and Nutrient Sources added
to Food on calcium silicate, silicon dioxide and silicic acid gel
added for nutriti onal purposes to food supplementsfollowing a
request from the European Commission. The EFSA Journal (2009)
1132, 1-24. Calcium silicate and silicon dioxide/silicic acid gel
added to food supplements The EFSA Journal (2009) 1132, 2-24
Piihappojen suolat (Silicates)
E551
on piidioksidi. Se on amorfista.
E552
on kalsiumsilikaattia. Sitä on hydroitunuta ja amorfista .
E553a(i)
on magnesiumsilikaatti.
E553a(ii)
on magnesiumtrisilikaatti.
E553b
on talkkia.
E554
on natrium alumiinisilikaattia.
Nämä
ovat hyväksyttyjä elintarvikkeen lisäaineita EU.ssa.
(i.e.
E551, silicon dioxide, amor phous; E552, calcium silicate,
hydrous/anhydrous;
E553a(i),
magnesium silicate; E553a(ii), magnesium trisilicate; E553b talc;
E554 sodium
aluminosilicate)
are approved food additives within the EU.
Anoja
katsoi aiheelliseski, että piidioksidi lisättäisiin
elintarvikesupplementteihin, josta saisi piitä 700 milligrammaan
asti päivittäin..Piihappogeeli kollodaalisena dispersiona antaisi
196 mg piitä päivässä.
The
petitioner indicated that silicon dioxide will be added to food
supplements to supply up to
700
mg silicon/day. Silicic acid gel under the form of a colloidal
dispersion will be added to
supply
196 mg silicon/day.
Mutta
Paneli huomautti, että piin essentiellisyyttä ihmiselle ei ole
osoitettu vakututavasti eikä piin funktionaalista rooliakaan ole
tunnistettu. Ei ole asetettu mitään piin suositeltua saanti
ravinnossa.
The
Panel however notes that the essentiality ofs ilicon for man has not
been established and
that
a functional role for silicon has not been identified. A recommended
intake for silicon has
not
been set.
Ei
ole edes mitään spesifisiä tietojakaan olemassa
kalsiumsilikaattiperäisen piin tai kalsiumin biologisesta
saatavuudesta.
No
specific data on the bioavailability of either silicon or calcium
from calcium silicate have
been
provided.
Paneli
toteaa kalsiumsilikaatin matalan liukoisuuden suolahappoon ja
käytännöllisesti katsoen se ei liukene veteen ollenkaan. Mutta
koska puuttuu tätä koskeva erityistieto, ei voida antaa mitään
johtopäätöstä niin kalkin kuin piinkään biologisesta
saatavuudesta mainitusta lähteestä (kalsiumsilikaatista).
The
Panel notes the low solubility of calcium silicate in hydrochloric
acid and its practical insolubility in water, but in the absence
of specific data, cannot reach a conclusion on the bioavailability
of either calcium or silicon from the source.
Ei ole
myöskään mitään jätetty tarkasteltavaksi mitään tietoja
piidioksidi- tai piihappogeeli-peräisen piin biologisesta
saatavuudesta. Kuitenkin on olemassa useita tutkimuksia, jotka ovat
osoittaneet samankaltaisissa muodoissa olevan piin olleen helposti
saatavilla ja monissa tapauksissa absorboituneen samalla tavalla
kuin pii nesteistä.
No
data have been submitted on the bioavailability of silicon from
either silicon dioxide or
silicic
acid gel. However, several studies have shown that silicon present
under similar form
was
readily available from foods and in many cases showed absorption
similar to that of
silicon
from liquids.
Edelleen
ottaen huomioon piidioksidin ja piihapon muuttumisen
ortopiihappomuotoon hydraatiossa ja ortopiihappomuotoisen piin
biologisen saatavuuden Paneli on sitä mieltä, että piidioksidin
ja piihappogeelin pii on biologisesti saatavilla olevaa.
Furthermore,
given the conversion of silicon dioxide/silicic acid to
orthosilicic acid upon hydration, and the bioavailability of silicon
from orthosilicic acid, the Panel considers that silicon from
silicon dioxide/ silicic acid gel is bioavailable.
Vitamiinien
ja Mineraalien Asiantuntijaryhmä (EVM) on asettanut piin (Si)
päivittäisen käytön truvallisen ylärajan (SUL) tasoon 700
milligrammaa piitä (Si) päivässä aikuisille ( koko ikä
huomioonottaen) mikä merkitsee 12 milligrammaa piitä painokiloa
kohden päivässä kun aikuinen on 60 kg painava.
The
Expert group on Vitamins and Minerals (EVM) set a Safe Upper Level
(SUL) for daily
consumption
of silicon at 700 mg silicon/day for adults over a lifetime
(equivalent to 12 mg
silicon/kg
body weight/day for a 60 kg adult).
Kalsiumille
asetettu siedettävä yläraja (TUL) on aikuiselle 2500 mg
päivässä, mikä tarkoittaa 41.3 mg kalsiumia painokiloa kohden
päivässä.
The
Tolerable Upper Intake Level (TUL) for calcium is 2500 mg/day for
adults (equivalent to 41.3 mg calcium/kg body weight/day).
EFSA-
paneli joka käsitteli ravintovalmisteita, ravitsemusta ja
allergioita (NDA) ei voinut asettaa piille (Si) yläraja-arvoa,
mutta arvioi kuitenkin tyypillisen päivittäisen piin(Si) saannin
ravinnossa olevan noin 20 – 50 mg mikä on noin 0,3- 0,8 mg
painokiloa kohden päivässä, kun aikuinen painaa 60 kg , eikä
tällainen saanti todennäköisesti aiheuta mitään haitallisia
vaikutuksia.
The
EFSA Panel on Dietetic products, Nutrition and Allergies (NDA) was
unable to set a UL
for
silicon, but estimated that the typical dietary intake of 20-50 mg
silicon/day (equivalent to
0.3-0.8
mg/kg body weight/day in a 60 kg person) is unlikely to cause
adverse effects.
Vastaavasti
kalsiumin suhteen (a) keskimäärainen saanti ja (b) 97.5
persentiilin saanti elintarvikkeista ja ravintolisistä saattaisi
vaihdella (a) 823- 1084 mg alueella ja (b) 1560- 2110 mg
henkilöä kohden päivässä
For
calcium, the mean and 97.5th
percentile anticipated total exposure from food and food
supplements
would vary from 823 to 1084 mg /person/day and 1560 to 2110
mg/person/day,
respectively.
Paneli
teki johtopäätöksekseen ottamalla huomioon silikonin saannin
700 mg päivässä (SUL, minkä EVM on lisävalmistelle
vahvistanut) ja aikuisten ravintoperäisen kalkin saannin 2500
mg (TUL, mikä on SCF:n vahvistama raja) , että kalsium(Ca++) ja
pii (Si) altistus ravintolisä- kalsiumsilikaatin ehdotetuista
käytöstä Ca ja Pi lähteenä ei ole turvallisuusongelma
edellyttäen, että noudatetaan, mitä on elintarvikelisien
käytöstä erikseen määrätty.
The
Panel concludes that, in view of the Safe Upper Level for silicon of
700 mg silicon/day
established
by the EVM for supplemental use and of 2500 mg calcium/day for
adults
established
by the SCF, the exposure to calcium and to silicon resulting from
the proposed
uses
of calcium silicate as a source of respectively silicon and calcium
in food supplements,
the
use of calcium silicate in food supplements at the proposed use
levels is of no safety
concern,
provided that it complies with the specifications for its use as a
food additive.
Paneli
teki myös johtopäätöksen, että piidioksidin käyttö
päivittäin 1500 milligrammaan asti ( mikä vastaa 700 mg piitä
päivässä) ja piihappogeelin käyttö, mistä tulee 200 mg piitä
päivässä ei ole turvallisuusongelma ravinolisiin liitettyinä.
The
Panel also concludes that the use of silicon dioxide up to 1500 mg
SiO2/day (equal to 700
mg/day)
and of silicic acid gel to supply up to 200 mg silicon/day, added to
food supplements, is of no safety concern.
Calcium
silicate and silicon dioxide/silicic acid gel added to food
supplements
The
EFSA Journal
(2009)
1132, 3-24
Avainsanat (Key words)
Kalsiumnsilikaatti,
Calcium silicate,
piihappo.
[silicic acid (H2SiO3),
kalsiumsuola
calcium salt (1:1)], CAS No. 10101-39-0,
ortopiihappo
[orthosilicic acid (H4SiO4), calcium salt (1:2)], CAS No.
1344-95-2,
piihapon
kalsiumsuola , Silicic acid calcium salt;
kalsiumhydrosilikaatti,
Calcium hydrosilicate;
Tobermorite.
Piidioksidi,
piihappogeeli Silicon dioxide/Silicic acid gel, CAS No.
7631-86-9,
Saostettu
piioksidi, precipitated silicon dioxide,
piigeeli,
silica gel,
hydroitunut
pii, hydrous silica,
hydroitu
piihappo, hydrated silicic acid,
polypiihappogeeli,
polysilicic acid gel,
fytoliittinen
pii, phytolithic silicon, E551
KTS: E- lisäaineluetelot
Viralliset kalsium- pii-ainekset eli
silikaatit ovat klumpförebyggande medel E- luetteloisssa ja
ruoanlaitossa estäen kokkaroitumisia ruoanvalmistuksessa.
(Olisikohan se sittenkin
toiminnallisesti essentielli hivenainemineraali, ehkä pitäisi
"kiiltävämpinä" trombosyyttejä, ettei ne sakkautuisi
niin heposti klimpeiksi. Tuli vain mieleen tässä. Mene ja tiedä).
E551 |
Kiseldioxid |
Silikat |
Klumpförebyggande
medel Tabletthjälpmedel [1] |
|
E552 |
Kalciumsilikat |
Silikat |
Klumpförebyggande
medel Tabletthjälpmedel [1] |
|
E553a |
Magnesiumsilikat
Magnesiumtrisilikat |
Silikat |
Klumpförebyggande
medel Tabletthjälpmedel [1] |
|
E553b |
Talk |
Silikat |
Klumpförebyggande
medel Tabletthjälpmedel Släppmedel [1] |
|
E554 |
Natriumaluminiumsilikat |
Silikat |
Klumpförebyggande
medel Tabletthjälpmedel [1] |
|
E555 |
Kaliumaluminiumsilikat |
Silikat |
Klumpförebyggande
medel Tabletthjälpmedel [1] |
|
E556 |
Kalciumaluminiumsilikat |
Silikat |
Klumpförebyggande
medel Tabletthjälpmedel [1] |
|
E558 |
Bentonit |
Silikat |
Antioxidationsmedel
och Klumpförebyggande
medel |
Annullerat p g a att det ej
används längre. [31] |
E559 |
Aluminiumsilikat |
Silikat |
Klumpförebyggande
medel [1] |
27.4. 2013
torsdag 25 april 2013
Liponihappo
http://en.wikipedia.org/wiki/Lipoic_acid
Liponihappo on thioctic acid, Lipoic acid englanniksi.
Keho tekee tämän hapon (R) LA enantiomeerimuotoa. jota esiintyy luonnossa, ja joka on essentielli kofaktori neljän mitokondriaentsyymin kompleksille ja aerobiselle aineenvaihdunnalle.
(S)LA muotoa ei ole esiitynyt ennen vuotta 1952, jolloin selviteltiin molekyylistruktuuria. Tarvittiin 10 tonnia maksakudosta, että saatiin 30 mg liponihappoa.
Tästä jo voi ymmärtää, että kehossa esiintyvät määrät ovat pieniä, plasmassa nanogrammoja 12,3- 43,1 ng/ ml RLA muotoa, joka oli se luonnollinen muoto.
On ymmärrettävää., että aineen havaitsemista ja strukturoimista ponnisteltiin kovasti, koska se muodostaa hiilihydraattiaineenvaihdunnassa olennaisessa pisteessä aivan välttämättömän rattaan omien molekyyliensä muodostaman syklin avulla ( eri entsyymeissä kiinni)
LipS2----- --(Ac-S) (Lip-SH )------- Li(SH)2-------Lip S2
LipS2 , LA Lipoic acid ( Käytännössä Lipoamide)
AcS- acetyl- ryhmä joka liittyy liponihapon toiseen rikkiin S. Toisessa on tällöin pelkistynyt -SH. tioli pääty.
Lip (SH)2 nyt on molemmissa rikeissä vetyä, Dihydrolipoic-acid (käytännössä dihydrolipoamide kiinni enstyymissä)
Arveltiin kyseessä olleen vitamiinin, koska siinä samassa pisteessä tarvittiin useita essentiellejä vitamiineja ( Biotiini, Tiamiini, B2, niasiini, koentsyymi A), mutta löydettiin ihmisgenomista sen synteesiä koodaava järjestelmä.
MITEN KEHO TEKEE LIPONIHAPPOA?
Sitä rakentuu tavallisen rasvahapposynteesin yhden rasvahapon (C8:0) vaiheesta, 8 -hiilisestä oktaanihaposta, joka oktanyyli-ACP kompleksina kuljetetaan oktanyylitransferaasientyymin lipoyyli domaanikohtaan.(Lip)
(ACP tarkoittaa acyl carrier protein, rasvahappotähteitä kuljettava proteiini)
octanyyli- ACP --- (+2S) ---Lip-ACP --- LipDomaaniin ( entsyymissä) + ACP-SH
Kehoon tulee orgaanista rikkia cysteiiniaminohapon avulla.
Lipoyylisyntaasipolypeptidin (lipoyl synthase) kahdesta sulfaatista tulee nuo kaksi rikkiä( +2S) liponihapon C6 ja C8 hiileihin.
Tässä on sitten eräänlainen radikaali SAM- mekanismi apuna. Sitaatti Wikistä.
In enzymology, a lipoyl synthase (EC 2.8.1.8) is an enzyme that catalyzes the chemical reaction
Yleensä kaikki relevantti tapahtuma vaatii S- ja N molekyylien ilmenemää kuvioissaan. Ne muokkaavat kehyksiä, struktuuria, energia-aineitten aineenvaihduntaa suorittaville tekijöille, jotka eivät " häviä" prosessin aikana, vaan suorittavat syklistä palautumista käyttömuotoon ja säilyvät aikansa. Joskus ne tietysti vanhenevat ja menevät myös energiaksi jaerittyvät, jos niitä ei keho pysty pilkkomaan.
Mikä on yhden (R)LA molekyylin, liponihapon IKÄ, sitä ei tästä artikkelista näe. Kuinka monta (tuhatta) sykliä se voi tehdä? Kataboliastakin täytyy hakea jokin toinen lähde. Arvelen että sen ikä voi olla riippuvainen sen käyttötarpeesta ja vaihteen normaaliudesta ( hiilihydraattivaihde, rasvankäyttävaihde) .
Näitten rakenneatomien N ja S yleinen suhde kehossa on 6: 1 typpeä ja rikkiä. Ja koska kudokset ja molekyylit vanhenevat, niin niitä erittyy päivittäin ja sen takia tarvitaan päivittäin proteiinia josta saadaan lisää N ja S ( typpeä ja rikkiä) . Miten on liponihapon normaalisaanti ruoassa? Ja miten hyvin sitä syntetisoituu itse kullakin? Koska se ei ole essentielli vitamiini, ja kuitenkin joskus siitä kai on havaittu relatiivia (funktionaalista) puutetta, nin se lie ehdollisesti essentielli, joissain erityisissä tapauksissa essentielli
Iän mukana (R)LA synteesi laskee ja samoin progredioivissa taudeissa.
Thioctic acid , Lipoic acid
Lopuksi tästä oktanyylirasvahaposta on siis muodostunut tioktihappo, jossa näitä orgaanisia rikkejä sijaitsee, Toinen pää on karboksyyliterminaali (-COOH) ja toisessa päässä on ditionaaliterminaali., rengas, jossa on kaksi rikkiä ja kolme hiiltä. Rikkien välinen kohta voi redusoitua kahdeksi SH- ryhmäksi tai oksidoitua takaisin -S-S- sillaksi.Kehossa tämä ei esiinny vapaana, kuten mainittu.
Luonnossa muodostuu vain (R) LA enantiomeeria mutta syntetisoitaessa 1952 saatiin myös (S) LA enantiomeeria , jolla ei ole biologista aktiivisuutta, päin vastoin se voi olla (R) muodon kompetitiivinen inhibiittori.
RLA liponihappoa tavataan mitokondrioissa, peroksisomeissa, tumassa ja muissa organelleissa.
Ennen kuin alkaa ajatella että ongelmat metaboliassa on liponihappopisteessä, tulee myös katsoa ettei ongelma ole siinä koko kompleksissa, mikä sitä ympäröi ( B1, aktivoitunut B1 tiamiinipyrofosfaatti, koentsyymi A, biotiini, B2 entsyymin sykli, FAD- FADH2, nikotinamidin sykli NAD, NADH + H+ ja mahdolliseseti jotain muitakin.
Jos metioniini SAM- järjestelmää tarvitaan, silloin asiiaan liittyy jo foolihappo, B12- vitamiini ehkä BH4:kin kuka ties.
Monta kertaa rasva ja sokeriaineenvaihdunnan pätsipointtia ( palorypälehappopistettä) rasittaa liikunnan puute, aivan täysin epätasapainossa oleva energia-aineitten tarjonta tai kauempana tästä kohdasta sijaitseva tukos tai jokin entsyymimutaatio. Liikunta ehkä pahin puutos nykyajan ihmisellä.
Linkkejä:
Koska liponihapossa on SH- ryhmiä, se on myös helposti myrkyttyvä kohta. Liponihapon SH- ryhmien ja S-S- sidoksen vaihtelu on työväline eikä niinkään toimi "antioksidanttina" , vaan tavallisten aineenvaihduntareaktioitten tärkeänä työkaluna ja oksidanttimuoto on se työkalu, joka ottaa vastaan siirrettävän palan. ja samalla asteittan redusoituu ja siten sen on palattava oksidanttimuotoon, mutta tuo redusoitunut välivaihe altistaa sen myrkyille.
http://www.ncbi.nlm.nih.gov/pubmed/23398199
Liponihappo on thioctic acid, Lipoic acid englanniksi.
Keho tekee tämän hapon (R) LA enantiomeerimuotoa. jota esiintyy luonnossa, ja joka on essentielli kofaktori neljän mitokondriaentsyymin kompleksille ja aerobiselle aineenvaihdunnalle.
(S)LA muotoa ei ole esiitynyt ennen vuotta 1952, jolloin selviteltiin molekyylistruktuuria. Tarvittiin 10 tonnia maksakudosta, että saatiin 30 mg liponihappoa.
Tästä jo voi ymmärtää, että kehossa esiintyvät määrät ovat pieniä, plasmassa nanogrammoja 12,3- 43,1 ng/ ml RLA muotoa, joka oli se luonnollinen muoto.
On ymmärrettävää., että aineen havaitsemista ja strukturoimista ponnisteltiin kovasti, koska se muodostaa hiilihydraattiaineenvaihdunnassa olennaisessa pisteessä aivan välttämättömän rattaan omien molekyyliensä muodostaman syklin avulla ( eri entsyymeissä kiinni)
LipS2----- --(Ac-S) (Lip-SH )------- Li(SH)2-------Lip S2
LipS2 , LA Lipoic acid ( Käytännössä Lipoamide)
AcS- acetyl- ryhmä joka liittyy liponihapon toiseen rikkiin S. Toisessa on tällöin pelkistynyt -SH. tioli pääty.
Lip (SH)2 nyt on molemmissa rikeissä vetyä, Dihydrolipoic-acid (käytännössä dihydrolipoamide kiinni enstyymissä)
Arveltiin kyseessä olleen vitamiinin, koska siinä samassa pisteessä tarvittiin useita essentiellejä vitamiineja ( Biotiini, Tiamiini, B2, niasiini, koentsyymi A), mutta löydettiin ihmisgenomista sen synteesiä koodaava järjestelmä.
MITEN KEHO TEKEE LIPONIHAPPOA?
Sitä rakentuu tavallisen rasvahapposynteesin yhden rasvahapon (C8:0) vaiheesta, 8 -hiilisestä oktaanihaposta, joka oktanyyli-ACP kompleksina kuljetetaan oktanyylitransferaasientyymin lipoyyli domaanikohtaan.(Lip)
(ACP tarkoittaa acyl carrier protein, rasvahappotähteitä kuljettava proteiini)
octanyyli- ACP --- (+2S) ---Lip-ACP --- LipDomaaniin ( entsyymissä) + ACP-SH
Kehoon tulee orgaanista rikkia cysteiiniaminohapon avulla.
Lipoyylisyntaasipolypeptidin (lipoyl synthase) kahdesta sulfaatista tulee nuo kaksi rikkiä( +2S) liponihapon C6 ja C8 hiileihin.
Tässä on sitten eräänlainen radikaali SAM- mekanismi apuna. Sitaatti Wikistä.
In enzymology, a lipoyl synthase (EC 2.8.1.8) is an enzyme that catalyzes the chemical reaction
- protein N6-(octanoyl)lysine + 2 sulfur + 2 S-adenosyl-L-methionine protein N6-(lipoyl)lysine + 2 L-methionine + 2 5'-deoxyadenosine
Yleensä kaikki relevantti tapahtuma vaatii S- ja N molekyylien ilmenemää kuvioissaan. Ne muokkaavat kehyksiä, struktuuria, energia-aineitten aineenvaihduntaa suorittaville tekijöille, jotka eivät " häviä" prosessin aikana, vaan suorittavat syklistä palautumista käyttömuotoon ja säilyvät aikansa. Joskus ne tietysti vanhenevat ja menevät myös energiaksi jaerittyvät, jos niitä ei keho pysty pilkkomaan.
Mikä on yhden (R)LA molekyylin, liponihapon IKÄ, sitä ei tästä artikkelista näe. Kuinka monta (tuhatta) sykliä se voi tehdä? Kataboliastakin täytyy hakea jokin toinen lähde. Arvelen että sen ikä voi olla riippuvainen sen käyttötarpeesta ja vaihteen normaaliudesta ( hiilihydraattivaihde, rasvankäyttävaihde) .
Näitten rakenneatomien N ja S yleinen suhde kehossa on 6: 1 typpeä ja rikkiä. Ja koska kudokset ja molekyylit vanhenevat, niin niitä erittyy päivittäin ja sen takia tarvitaan päivittäin proteiinia josta saadaan lisää N ja S ( typpeä ja rikkiä) . Miten on liponihapon normaalisaanti ruoassa? Ja miten hyvin sitä syntetisoituu itse kullakin? Koska se ei ole essentielli vitamiini, ja kuitenkin joskus siitä kai on havaittu relatiivia (funktionaalista) puutetta, nin se lie ehdollisesti essentielli, joissain erityisissä tapauksissa essentielli
Iän mukana (R)LA synteesi laskee ja samoin progredioivissa taudeissa.
Thioctic acid , Lipoic acid
Lopuksi tästä oktanyylirasvahaposta on siis muodostunut tioktihappo, jossa näitä orgaanisia rikkejä sijaitsee, Toinen pää on karboksyyliterminaali (-COOH) ja toisessa päässä on ditionaaliterminaali., rengas, jossa on kaksi rikkiä ja kolme hiiltä. Rikkien välinen kohta voi redusoitua kahdeksi SH- ryhmäksi tai oksidoitua takaisin -S-S- sillaksi.Kehossa tämä ei esiinny vapaana, kuten mainittu.
Luonnossa muodostuu vain (R) LA enantiomeeria mutta syntetisoitaessa 1952 saatiin myös (S) LA enantiomeeria , jolla ei ole biologista aktiivisuutta, päin vastoin se voi olla (R) muodon kompetitiivinen inhibiittori.
RLA liponihappoa tavataan mitokondrioissa, peroksisomeissa, tumassa ja muissa organelleissa.
Ennen kuin alkaa ajatella että ongelmat metaboliassa on liponihappopisteessä, tulee myös katsoa ettei ongelma ole siinä koko kompleksissa, mikä sitä ympäröi ( B1, aktivoitunut B1 tiamiinipyrofosfaatti, koentsyymi A, biotiini, B2 entsyymin sykli, FAD- FADH2, nikotinamidin sykli NAD, NADH + H+ ja mahdolliseseti jotain muitakin.
Jos metioniini SAM- järjestelmää tarvitaan, silloin asiiaan liittyy jo foolihappo, B12- vitamiini ehkä BH4:kin kuka ties.
Monta kertaa rasva ja sokeriaineenvaihdunnan pätsipointtia ( palorypälehappopistettä) rasittaa liikunnan puute, aivan täysin epätasapainossa oleva energia-aineitten tarjonta tai kauempana tästä kohdasta sijaitseva tukos tai jokin entsyymimutaatio. Liikunta ehkä pahin puutos nykyajan ihmisellä.
Linkkejä:
Koska liponihapossa on SH- ryhmiä, se on myös helposti myrkyttyvä kohta. Liponihapon SH- ryhmien ja S-S- sidoksen vaihtelu on työväline eikä niinkään toimi "antioksidanttina" , vaan tavallisten aineenvaihduntareaktioitten tärkeänä työkaluna ja oksidanttimuoto on se työkalu, joka ottaa vastaan siirrettävän palan. ja samalla asteittan redusoituu ja siten sen on palattava oksidanttimuotoon, mutta tuo redusoitunut välivaihe altistaa sen myrkyille.
http://www.ncbi.nlm.nih.gov/pubmed/23398199
Pyruvate dehydrogenase complex (PDHc) is the site of action of a new class of herbicides.
http://en.wikipedia.org/wiki/Pyruvate_dehydrogenase
Liponihapon SH- ryhmät myrkyttyvät elohopeasta ja arseniitista. BAL anti-lewisiitti vapauttaa kehoa arseniitin myrkyttämästä liponihaposta. (II maailmansota)
http://en.wikipedia.org/wiki/Pyruvate_dehydrogenase
onsdag 23 januari 2013
Sapropteriini, Tetrahydrobiopteriini
Redusoitu biopteriini (BH4) , jota kehon pitää pystyä valmistamaan, koska kaikkien NOS-entsyymien aktiivisuudelle se on välttämätön tekijä.
Fenyylialaniinihydroksylaasi eli PAH löytyi ensimmäisenä.[1] Todettiin, että tetrahydrobiopteriinin puute saa aikaan harvinaisen aineenvaihdunnan häiriön, joka lisää veren fenyylialaniinipitoisuutta. Fenyylialamiinin kertyminen elimistöön aiheuttaa kehitysvammaisuutta ja muita vakavia terveysongelmia.
Tetrahydrobiopteriini ja Fe2+-ioni ovat tryptofaanihydroksylaasin toiminnalle välttämättömiä koentsyymejä [2] jotka vaikuttavat serotoniiniaineenvaihdunnan kautta muun muassa keskushermoston toimintaa.
Saunassa kudosten lämmetessä elimistöön syntyy tetrahydrobiopteriinia, jota tarvitaan verisuonten normaalin toiminnan ylläpitämisessä.
Tetrahydrobiopteriinista käytetään myös nimeä 5,6,7,8-tetrahydrobiopteriini.
Tetrahydrobiopteriinin kemiallinen kaava on C9H15N5O3, moolimassa 241,247 g/mol ja CAS-numero 17528-72-2.
Myös: tryptofaanin aineenvaihdunta-alue
Tryptophan hydroxylase (TPH) is an enzyme involved in the synthesis of the neurotransmitter serotonin. TPH catalyzes the following chemical reaction L-tryptophan + tetrahydrobiopterin + O2 5-Hydroxytryptophan + dihydrobiopterin + H2O It employs one additional cofactor, iron.
Jos nukkuu hyvin ei voi suorittaa hyvä motorista prestaatiota samaan aikaan.
http://cat.inist.fr/?aModele=afficheN&cpsidt=20533018
- Suomalainen Wiki sanoo näin:
Fenyylialaniinihydroksylaasi eli PAH löytyi ensimmäisenä.[1] Todettiin, että tetrahydrobiopteriinin puute saa aikaan harvinaisen aineenvaihdunnan häiriön, joka lisää veren fenyylialaniinipitoisuutta. Fenyylialamiinin kertyminen elimistöön aiheuttaa kehitysvammaisuutta ja muita vakavia terveysongelmia.
Tetrahydrobiopteriini ja Fe2+-ioni ovat tryptofaanihydroksylaasin toiminnalle välttämättömiä koentsyymejä [2] jotka vaikuttavat serotoniiniaineenvaihdunnan kautta muun muassa keskushermoston toimintaa.
Saunassa kudosten lämmetessä elimistöön syntyy tetrahydrobiopteriinia, jota tarvitaan verisuonten normaalin toiminnan ylläpitämisessä.
Tetrahydrobiopteriinista käytetään myös nimeä 5,6,7,8-tetrahydrobiopteriini.
Tetrahydrobiopteriinin kemiallinen kaava on C9H15N5O3, moolimassa 241,247 g/mol ja CAS-numero 17528-72-2.
- Vuodelta 2007 on seuraava laaja artikkeli:
- KUVA , Fenylalaniini, Tyrosiini, DOPA aineenvaihdunta alue
Myös: tryptofaanin aineenvaihdunta-alue
Tryptophan hydroxylase (TPH) is an enzyme involved in the synthesis of the neurotransmitter serotonin. TPH catalyzes the following chemical reaction L-tryptophan + tetrahydrobiopterin + O2 5-Hydroxytryptophan + dihydrobiopterin + H2O It employs one additional cofactor, iron.
Jos nukkuu hyvin ei voi suorittaa hyvä motorista prestaatiota samaan aikaan.
http://cat.inist.fr/?aModele=afficheN&cpsidt=20533018
- Myös tämä dihydropteriinista BH2
J Phys Chem A. 2007 May 24;111(20):4280-8. Epub 2007 May 3. Singlet oxygen (O2(1Deltag)) quenching by dihydropterins.
Source
Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CONICET, Boulevard 113 y 64 (1900) La Plata, Argentina.Abstract
Pterins
belong to a class of heterocyclic compounds present in a wide range of
living systems. They participate in relevant biological functions and
are involved in different photobiological processes. Dihydropterins are
one of the biologically active forms of pterins. The photoinduced
production and quenching of singlet oxygen (1O2) by a series of
dihydropterins (7,8-dihydrobiopterin (DHBPT), 7,8-dihydroneopterin
(DHNPT), 6-formyl-7,8-dihydropterin (FDHPT), sepiapterin (SPT),
7,8-dihydrofolic acid (DHFA), and 7,8-dihydroxanthopterin (DHXPT)) in
aqueous solution at physiological pH ( approximately 7) were
investigated, and the quantum yields of 1O2 production (PhiDelta) and
rate constants of total quenching (kt) of 1O2 were determined.
Studied compounds do not produce 1O2 under UV-A irradiation and are very efficient 1O2 quenchers. The chemical reactions between 1O2 and dihydropterin derivatives were investigated, and the corresponding rate constants (kr) were found to be particularly high.
The oxidized pterin derivatives, biopterin (BPT), neopterin (NPT), 6-formylpterin (FPT), and folic acid (FA), were identified and quantified during the reaction of 1O2 with DHBPT, DHNPT, FDHPT, and DHFA, respectively.
Besides the oxidation of the dihydropyrazine ring to yield the corresponding oxidized pterins, a second oxidation pathway, leading to fragmentation of the dihydropterin and formation of non-pterinic products, was identified. Mechanisms and biological implications are discussed.
Studied compounds do not produce 1O2 under UV-A irradiation and are very efficient 1O2 quenchers. The chemical reactions between 1O2 and dihydropterin derivatives were investigated, and the corresponding rate constants (kr) were found to be particularly high.
The oxidized pterin derivatives, biopterin (BPT), neopterin (NPT), 6-formylpterin (FPT), and folic acid (FA), were identified and quantified during the reaction of 1O2 with DHBPT, DHNPT, FDHPT, and DHFA, respectively.
Besides the oxidation of the dihydropyrazine ring to yield the corresponding oxidized pterins, a second oxidation pathway, leading to fragmentation of the dihydropterin and formation of non-pterinic products, was identified. Mechanisms and biological implications are discussed.
- PMID:
- 17474729
- [PubMed - indexed for MEDLINE]
- Jos sydänlihassolun biopteriinin synteesi on vajeista , sepiapteriinimuodon anto voi nostaa BH4 ja BH2 pitoisuutta.
- http://www.ncbi.nlm.nih.gov/pubmed/18835915
Etiketter:
BH2 dihyropteriini,
BH4,
fenylalaniini,
tetrahydrobiopteriini,
THB,
Tryptofaani
torsdag 17 januari 2013
tisdag 8 januari 2013
Vähäbakteerisesta ruoasta vuodelta 1993
Miten alentaa bakteerimäärää ruoassa?
Esimerkkiinä AJ Pattisonin neutropeniadieetti vuodelta 1993. Täallinen oli tarkoitettu ensisijassa lapsille, joilla oli maligni veritauti, hoitona sytostaatteja ja koko kehon säteilytys ennen luuydinsiirtoa, sillä hoidossa häviää valkosolutkin joksikin aikaa ja silloin immuunivaste on hyvin heikkona. bakteerien tuloa kehoon voi alentaa, katsomalla että ruoka ei tuo liikaa bakteereja mukanaan ja mutenmin on hygienisesti tehtyä. Pattisonin dieettiä on myöhemmin modifioitu lievemmäksi, mutta tämä on hyvä pitää tallella tämäkin ohje pahan päivän varalta.
Alla oleva artikkeli on englantilainen:
LÄHDE: Pattison J Amanda. Review of current practice in clean diets in the UK. Journal of Human Nutrition and dietetics, 1993; 6; 3-11.
Introduction
Bone marrow transplant (BMT) can be an effective method of improving the prognosis of patients with resistant malignant diseases involving the bone marrow, usually leucemia ( Pachedly, 1983). Before infusion of the donor marrow, patients receive an intensive course of chemotherapy, usually combined with total body irradiation. This effectively destroys all the cells in the bone marrow, causing the patient to be free from disease and reducing the risk of graft rejection and graft-versus-host disease. However, the destruction of neutrophils leads to a diminished inflammatory response to infection (Bast, 1982, cited in Fisher, 1991). Lymphocyte levels are also depressed after total body irradiation, but can also be affected by malnutrition ( Fischer, 1991). Haffajee & Augburn ( 1985, cited in Fisher, 1991) found that the lymphocyte levels of patients with unresectable cancer of the oesophagus rose to normal when the patients achieved a positive nitrogen balance. This would suggest the use of supplementary feeding in such patients before and after transplantation. A complete enteral feed (EN) should be considered over total parenteral nutrition (TPN) or an elemental enteral feed due to intestinal atrophy and overgrowth of gut bacteria. This is accelerated if the intestinal mucosa is damaged after intensive chemotherapy and total body irradiation ) Alexander, 1990; Barber et al. 1990).
Immunosuppression lasts for several weeks after transplantation and infection is the major cause of morbidity (Naiseef & Maki, 1981). Initially, the patient is usually maintained in closed cubicle or occasional laminar air flow (LAF) unit. Staff and visitors generally wear gowns, gloves and masks to minimize sources of infection from the hospital environment.
Food is one potential source of infection and there is usually some level of “clean diet” employed. This ranges from following basic food-hygiene guidelines to sterile diets used in conjunction with gut-sterilizing antibiotics. In addition to BMT patients, some control may be placed on food for other immunosuppressed patients, e.g. those having conventional chemotherapy.
The clean diet followed by BMT patients at Sheffield Childrens Hospital prior to the present review can be seen in Appendix 2. Additional information was given on suitable meal choices, individual portions available from catering and a suggested meal pattern.
At S. Hospital, in view of the restricted food choice imposed and the improved clinical management of BMT patients, colleagues in the haematology team questioned whether a clean diet was necessary for these patients or, indeed, if its use should be extended to all immunosuppressed patients.
In response, this review was undertaken which aimed to look at current practice in clean diet among UK BMT centres and to use the results together with discussion amongst collegues at S. Hospital to formulate new clean food guidelines.
Method
The dietitians at each of the 20 centres in the UK carrying out BMTs in children were asked for information on their current practice in “clean” diets. Diet sheets and/ or protocols were received from 16 of these centres.
Results
Table 1 is a collation of the information received, including 12 different diet sheets. Several centres use the information provided by the Manual of Dietetic Practice (Thomas, 1988)
Table 1
Food group (and frequency)
WATER
Tap-water (3)
Boiled tap-water (4)
Tap-water let run (3)
Sterile water only (2)
Boiled tap or sterile (2)
MINERAL WATER
Bottled only (1)
Canned only (1)
Sparkling only (1)
Any (1)
Evian, Perrier only (1)
No mention (7)
DRINKS
COFFEE
Sachets (4)
Boiling water(2)
No mention( 6)
TEA
Tea bags (3)
Irradiated (1)
Boiling water (2)
No mention (6)
SOFT DRINKS
Canned or bottled (7)
Sparkling only (2)
Repasteurized squash (1)
Cordial only (2)
DAIRY PRODUCTS
MILK
Sterilized only (6)
Pasteurized (6)
DAIRY PRODUCTS
YOGHURT
Any (2)
No live yoghurt (4)
Long-life only (1)
No mention (4)
CHEESE
Cooked only (1)
Processed only (3)
Cooked/processed only (3)
No blue or soft (3)
No mention (2)
DAIRY PRODUCTS
BUTTER
Individual portion (7)
Any-refrigerated (4)
Autoclaved (1)
MEAT and FISH
Well cooked (10)
Tinned (6)
Frozen (4)
No cold meat (1)
Good quality (2)
EGGS
Well cooked (9)
Pasteurized (1)
Ni mention (2)
FRUIT
Tinned only ( 3)
Peeled-raw allowed (3)
No raw (6)
No dried (4)
VEGETABLES
No salad/ raw
Cooked only (10)
Frozen/tinned only (2)
BREAD
Any (3)
Fresh loaf /3)
Toasted (3)
Double-baked (1)
Breakfast cereal:
Any (1)
Individual portion (9)
No dried fruit/ nuts/ sugar coated (1)
No mention (1)
BISCUITS, CAKES
Any (2)
Individual portions (6)
Plain only (1)
No cream cakes (1)
Home-baked only(1)
No cakes (1)
CHOCOLATES SWEETS
Individual portions (5)
Double-wrapped (2)
No nuts/dried fruit (1)
No chocolate (3)
No mention(1)
DESSERTS
Tinned/individual portions (4)
No custard/blancmange (1)
Freshly cooked (2)
No instant desserts (2)
No mention (1)
JAM, SAUCES, SUGAR etc
Individual portions (4)
Irradiated pepper (1)
No mayonnaise (1)
Any (3)
No mention (5)
As can be seen, individual portions of butter, salt, sauces, etc. and individually wrapped biscuits, cakes, desserts and breakfast cereals are favoured by most centres. This minimizes wastage and avoids the use of leftover food.
Meat products and cold meats are generally avoided as, they are a common source of infection, particularly if stored incorrectly.
Centres which use only toasted bread do so to kill any surface yeasts. Pepper and spices must generally be cooked as they are a major source of bacterial spores.
There appears to be no consensus of opinion regarding the use of tap-water and mineral water. Sterile water is used by four centres and tap-water is used by four centres. Boiled water is the most popular, but other centres use untreated tap-water or tap-water which has run for several minutes.
The bacterial content of mineral waters has been questioned (DHSS, 1988), but several centres do use them. Again, no common patterns within the type of water used can be seen. Unboiled mineral water or tap-water should certainly not be given to healthy infants, but their use for immunosuppressed children requires further clarification. There is some support for the view that carbonated drinks tend to have a lower bacterial count and this presumably forms the basis of the recommendation to use sparkling drinks.
Cooking methods
Table 2 shows the methods of food preparation for BMT patients. The Manual of Dietetic Practice recommends the use of conventional cookers and especially pressure-cookers, with a minimum core temperature of 70 degrees C. One centre encourages the use of slow cooking, e.g. stewing, braising and roasting, to kill bacteria most effectively. Only one centre mentions the use of microwave ovens; there they are used only for reheating cooked food on the ward. Although most centres use conventional methods for cooking, a diet cook may prepare the food separately; it is cooked quickly and thoroughly and served immediately to minimize multiplication of bacteria.
Instruction for ward staff
Only three centres included instructions for ward, including preparation for eating, storage and service of food and treatment or disposal of food and utensils after each meal.
At S Hospital, a meal is served as soon as it is cooked and transferred from a covered plate to a clean plate inside the cubicle. All crockery and cutlery are soaked in a sterilizing fluid after washing, rinsed and stored in the cubicle, together with a selection of individually packaged snacks and vacuum-packed soft drinks.
Other centres vary in their degree of hygienic practice. The centre employing the sterile diet has its own housekeepers working in the LAF kitchen.
Information for home
At S Hospital, children may occasionally be discharged when their neutrophil count is >1x10E9/L. As this is below the normal range of 2.5- 7.5x10E9/L, some care with food is still necessary. Advice is given on ensuring food is as fresh as possible and refrigerated as necessary, not damaged or overripe, that food should be prepared in clean condition and that any food requiring cooking must be cooked thoroughly. Take-away food is not encouraged.
The Manual of Dietetic Practice offers similar advice, but states that no soft or raw eggs should be used, fruit and vegetables should be skinned and chilled cabinet foods should be avoided.
Three centres included literature for patients going home.
One or more of these centres advises against the following foods:
Poultry, cold meat, shellfish, raw eggs, soft and blue cheeses, dried fruit, raw vegetables, fresh cream and tap-water.
Dietary supplements
At S Hospital, commercial tube feeds and ready-prepared sip feeds without additional ingredients are used wherever possible to avoid contamination. Feeds are stored and prepared if necessary in a special feed unit under very clean conditions. The bottle or carton should be opened in the cubicle and either refrigerated in a sealed container for up to 24 hr or discarded if not used immediately. Prior to opening, bottles of prepared feed must be kept refrigerated. Information on the specific use of supplements was not received from other centres.
Table 2
Method Number of centres Comment
Main kitchen
Conventional cooking
Reheat in microwave oven .
11 centres
1 centre Diet cook generally follows detailed instructions
Cook chill 1 centre Only up to day of transplant
Ward kitchen 2 centres One used for BMT food preparation only
Gamma-irradiated/tinned food prepared in LAF uni 1 centre Sterile diet used for BMT patients
Discussion
Although the design of the survey provides only a limited amount of information, that which was received demonstrates that the level of restriction varies enormously between centres. The differences appear to be based on availably facilities and the individual views of staff. This is the case at S Hospital, where there are two closed cubicles available on the ward and very accommodating catering staff. Stricter measures have not been deemed necessary by the haematology team in the past. The use of LAF units as opposed to closed cubicles has decreased in popularity due to financial constraints and more effective antibiotic therapy. Studies have shown that total isolation can lead to low morale and poor appetite (Driedger & Burstall, 1987) and may not be more successful in reducing infection rates /Yates & Holland, 1973) when appropriate antibiotics are used.
Bacterial contamination
is by far the commonest cause of food poisoning with
· Salmonella causing 80-90% of cases in the general population, followed by
· Clostridium perfringes and
· Staphylococcus aureus.
High risk foods
( those which support multiplication of pathogens in the state they are to be eaten) are listed as cooked meat and poultry, dairy products, cooked eggs and egg products, shellfish and cooked rice.
Raw vegetables
have also been implicated as a source of infection for immunosuppressed patients from
· Pseudomonas aeruginosa
· Escherichia coli and
· Klebsiella species
(Shooter et al 1971; Kominos et al. 1972; Mutton et al 1980)
Contamination may occur during preparation of salad vegetables suggesting a need for scrupulous kitchen practice.
Bacterial testing of food
in US centres tend to be carried out only in LAF environments (Dezenhall et al, 1987) and was taken into account in only some of the centres surveyed here. The microbiology department at S Hospital does not feel that foodborne pathogens are an important source of infection in BMT patients and does not carry out routine microbiological testing of food.
One classification of the food to be “high risk”
Driedger et Burstall (1987) classified food according to bacterial levels and found the following foods to be “high-risk”: salads, fresh fruit and vegetables, non pasteurized dairy products and prepared snacks, desserts and condiments.
The number of organism that must be swallowed by a patient for intestinal colonization varies according to antibiotic therapy and the underlying disease. Animal studies have shown that in lowered resistance, only 10-100 organisms are needed for colonization, compared with 1 000 000 organisms in unimpaired resistance ( Van der Waajj et al 1972). After antibiotic therapy the intestine may be colonized with new pathogens after relatively few organisms have been ingested (Remington et Schimpff, 1981). The optimal temperature for multiplication of bacteria is 37 degree C and multiplication is rapid between 20 and 50 degree C. Food should be kept below 10 degree C or above the critical temperature 63 degrees C. Above this temperature, bacteria can no longer multiply. The Manual of Dietetic Practice recommends a minimum core temperature of 70 degrees C.
Ovens should be preheated
to a minimum temperature of 200 degrees C to raise the temperature of the food quickly. If food is to be boiled, e.g. vegetables, the water should be boiling before food is added to it.
Pressure-cooking is a good choice as long as the food is served immediately after cooking.
The use of microwave ovens
to cook food for BMT patients remains controversial. Their use was mentioned by only one centre surveyed here, which used microwave oven only for reheating cooked food. Microbes may only be inactivated in the presence of water, so dry foods may not be cooked effectively by microwave (Vela et Wu, 1979). In addition, Page et Martin, 1978, found that the survival
· Escherichia coli and
· Streptococcus cerevisiae on the inner surfaces of microwave oven was high when compared with the same organism in food.
Therefore, it is essential to disinfect the oven, especially if used for immunocompromized patients.
Fruuin et Gethertz (1982) found that bacteria were not killed as effectively by the rapid increase in temperature in microwave cooking as in conventional cooking, where food is held at high temperature for a long time.
However, Dreyfuss et Chipley (1980) found that microwave ovens had a destructive effect on Staphylococcus aureus due to radiation, in addition to the thermal effects found on conventional ovens.
There has been little documented evidence on the use and effectiveness of “clean” diets. Generally, there are four different levels of restriction.
Recently established centres in a US survey ( Dezenhall et al 1987) tended to use a modified ward diet ( normal diet excluding fruit and vegetables) and four centres had changed from sterile diet to a low-bacteria or modified ward diet. Reasons for the move towards less strict dietary procedures included limited availability of individual portions of sterile foods, lack of standardized recipes and low patient acceptance of autoclaved foods.
Preisler et al (1987) found a sterile diet afforded little or no advantage over a low-microbial diet and Yales et Holland (1973) showed a decreased incidence of Pseudomonas infections in both patients on a sterile diet and on a low-microbial diet.
Naiseef et Maki (1981) stated that it was possible for the simple measure of providing well-cooked food to provide considerable protection against endogenous infection caused by hospital acquired organisms.
Pizzo et al (1982) found that food selection became the focal point for patient frustration and also affected patient compliance with other medical procedures. A wider food selection added pleasure and variety to patient meals especially children.
Conclusion
Following the survey of current practice, discussions between the consultant haematologists, oncologists, microbiologists, ward staff, catering staff and dietitian reviewed the advice given to BMT patients at S Hospital. Several other factors were taken into account.
(1) There had been no record of food related infections in any immunosuppressed patient at the hospital.
(2) It was felt that the restrictions imposed by the clean diet made it difficult for the children to enjoy their food.
(3) It was felt that any advice given to patients undergoing BMT should be extended to any child undergoing chemotherapy as they would all be immunocompromised to some extent. Practically, this would be possible with new guidelines.
(4) The temperature of the food served from the ward trolley is regularly monitored to be higher than 63 degrees C. and therefore it was felt unnecessary to provide individual meals.
As a result. the advice now given is more in line with a more relaxed diet used in other centres for use at home. The advice sheet is given to all new patients on the oncology ward at the start of their treatment. The guidelines are to be continued on discharge.
Evaluation of patient acceptance and infection rates following the implementation of these guidelines will be carried out in the future.
( Appendix 1,2,3, ei ole kirjoitettuna tässä)
Esimerkkiinä AJ Pattisonin neutropeniadieetti vuodelta 1993. Täallinen oli tarkoitettu ensisijassa lapsille, joilla oli maligni veritauti, hoitona sytostaatteja ja koko kehon säteilytys ennen luuydinsiirtoa, sillä hoidossa häviää valkosolutkin joksikin aikaa ja silloin immuunivaste on hyvin heikkona. bakteerien tuloa kehoon voi alentaa, katsomalla että ruoka ei tuo liikaa bakteereja mukanaan ja mutenmin on hygienisesti tehtyä. Pattisonin dieettiä on myöhemmin modifioitu lievemmäksi, mutta tämä on hyvä pitää tallella tämäkin ohje pahan päivän varalta.
- (Näitä periaatteita toistivat myös 2000- 2001 dietetiikan luennoilla onkologiaan erikoistuneet dietistit Ruotsissa:
- "Hedelmät tulee kuoria valmiiksi.
- Sormin poimittavaa ruokaa ei saisi käyttää.
- Eläviä bakteereja sisältävää ruokaa pitäisi välttää.
- Ruoan valmistajan on pidettävä tarkka huoli käsien puhtaudesta .
- Syöpäpotilaille kaikki ruoka, minkä potilas syö, sitä oikeaa ruokaa. Huono ruokahalu on vaikea asia syöpätaudissa ja hoidon sivuvaikutuksena)".
Alla oleva artikkeli on englantilainen:
LÄHDE: Pattison J Amanda. Review of current practice in clean diets in the UK. Journal of Human Nutrition and dietetics, 1993; 6; 3-11.
Introduction
Bone marrow transplant (BMT) can be an effective method of improving the prognosis of patients with resistant malignant diseases involving the bone marrow, usually leucemia ( Pachedly, 1983). Before infusion of the donor marrow, patients receive an intensive course of chemotherapy, usually combined with total body irradiation. This effectively destroys all the cells in the bone marrow, causing the patient to be free from disease and reducing the risk of graft rejection and graft-versus-host disease. However, the destruction of neutrophils leads to a diminished inflammatory response to infection (Bast, 1982, cited in Fisher, 1991). Lymphocyte levels are also depressed after total body irradiation, but can also be affected by malnutrition ( Fischer, 1991). Haffajee & Augburn ( 1985, cited in Fisher, 1991) found that the lymphocyte levels of patients with unresectable cancer of the oesophagus rose to normal when the patients achieved a positive nitrogen balance. This would suggest the use of supplementary feeding in such patients before and after transplantation. A complete enteral feed (EN) should be considered over total parenteral nutrition (TPN) or an elemental enteral feed due to intestinal atrophy and overgrowth of gut bacteria. This is accelerated if the intestinal mucosa is damaged after intensive chemotherapy and total body irradiation ) Alexander, 1990; Barber et al. 1990).
Immunosuppression lasts for several weeks after transplantation and infection is the major cause of morbidity (Naiseef & Maki, 1981). Initially, the patient is usually maintained in closed cubicle or occasional laminar air flow (LAF) unit. Staff and visitors generally wear gowns, gloves and masks to minimize sources of infection from the hospital environment.
Food is one potential source of infection and there is usually some level of “clean diet” employed. This ranges from following basic food-hygiene guidelines to sterile diets used in conjunction with gut-sterilizing antibiotics. In addition to BMT patients, some control may be placed on food for other immunosuppressed patients, e.g. those having conventional chemotherapy.
The clean diet followed by BMT patients at Sheffield Childrens Hospital prior to the present review can be seen in Appendix 2. Additional information was given on suitable meal choices, individual portions available from catering and a suggested meal pattern.
At S. Hospital, in view of the restricted food choice imposed and the improved clinical management of BMT patients, colleagues in the haematology team questioned whether a clean diet was necessary for these patients or, indeed, if its use should be extended to all immunosuppressed patients.
In response, this review was undertaken which aimed to look at current practice in clean diet among UK BMT centres and to use the results together with discussion amongst collegues at S. Hospital to formulate new clean food guidelines.
Method
The dietitians at each of the 20 centres in the UK carrying out BMTs in children were asked for information on their current practice in “clean” diets. Diet sheets and/ or protocols were received from 16 of these centres.
Results
Table 1 is a collation of the information received, including 12 different diet sheets. Several centres use the information provided by the Manual of Dietetic Practice (Thomas, 1988)
Table 1
Food group (and frequency)
WATER
Tap-water (3)
Boiled tap-water (4)
Tap-water let run (3)
Sterile water only (2)
Boiled tap or sterile (2)
MINERAL WATER
Bottled only (1)
Canned only (1)
Sparkling only (1)
Any (1)
Evian, Perrier only (1)
No mention (7)
DRINKS
COFFEE
Sachets (4)
Boiling water(2)
No mention( 6)
TEA
Tea bags (3)
Irradiated (1)
Boiling water (2)
No mention (6)
SOFT DRINKS
Canned or bottled (7)
Sparkling only (2)
Repasteurized squash (1)
Cordial only (2)
DAIRY PRODUCTS
MILK
Sterilized only (6)
Pasteurized (6)
DAIRY PRODUCTS
YOGHURT
Any (2)
No live yoghurt (4)
Long-life only (1)
No mention (4)
CHEESE
Cooked only (1)
Processed only (3)
Cooked/processed only (3)
No blue or soft (3)
No mention (2)
DAIRY PRODUCTS
BUTTER
Individual portion (7)
Any-refrigerated (4)
Autoclaved (1)
MEAT and FISH
Well cooked (10)
Tinned (6)
Frozen (4)
No cold meat (1)
Good quality (2)
EGGS
Well cooked (9)
Pasteurized (1)
Ni mention (2)
FRUIT
Tinned only ( 3)
Peeled-raw allowed (3)
No raw (6)
No dried (4)
VEGETABLES
No salad/ raw
Cooked only (10)
Frozen/tinned only (2)
BREAD
Any (3)
Fresh loaf /3)
Toasted (3)
Double-baked (1)
Breakfast cereal:
Any (1)
Individual portion (9)
No dried fruit/ nuts/ sugar coated (1)
No mention (1)
BISCUITS, CAKES
Any (2)
Individual portions (6)
Plain only (1)
No cream cakes (1)
Home-baked only(1)
No cakes (1)
CHOCOLATES SWEETS
Individual portions (5)
Double-wrapped (2)
No nuts/dried fruit (1)
No chocolate (3)
No mention(1)
DESSERTS
Tinned/individual portions (4)
No custard/blancmange (1)
Freshly cooked (2)
No instant desserts (2)
No mention (1)
JAM, SAUCES, SUGAR etc
Individual portions (4)
Irradiated pepper (1)
No mayonnaise (1)
Any (3)
No mention (5)
As can be seen, individual portions of butter, salt, sauces, etc. and individually wrapped biscuits, cakes, desserts and breakfast cereals are favoured by most centres. This minimizes wastage and avoids the use of leftover food.
Meat products and cold meats are generally avoided as, they are a common source of infection, particularly if stored incorrectly.
Centres which use only toasted bread do so to kill any surface yeasts. Pepper and spices must generally be cooked as they are a major source of bacterial spores.
There appears to be no consensus of opinion regarding the use of tap-water and mineral water. Sterile water is used by four centres and tap-water is used by four centres. Boiled water is the most popular, but other centres use untreated tap-water or tap-water which has run for several minutes.
The bacterial content of mineral waters has been questioned (DHSS, 1988), but several centres do use them. Again, no common patterns within the type of water used can be seen. Unboiled mineral water or tap-water should certainly not be given to healthy infants, but their use for immunosuppressed children requires further clarification. There is some support for the view that carbonated drinks tend to have a lower bacterial count and this presumably forms the basis of the recommendation to use sparkling drinks.
Cooking methods
Table 2 shows the methods of food preparation for BMT patients. The Manual of Dietetic Practice recommends the use of conventional cookers and especially pressure-cookers, with a minimum core temperature of 70 degrees C. One centre encourages the use of slow cooking, e.g. stewing, braising and roasting, to kill bacteria most effectively. Only one centre mentions the use of microwave ovens; there they are used only for reheating cooked food on the ward. Although most centres use conventional methods for cooking, a diet cook may prepare the food separately; it is cooked quickly and thoroughly and served immediately to minimize multiplication of bacteria.
Instruction for ward staff
Only three centres included instructions for ward, including preparation for eating, storage and service of food and treatment or disposal of food and utensils after each meal.
At S Hospital, a meal is served as soon as it is cooked and transferred from a covered plate to a clean plate inside the cubicle. All crockery and cutlery are soaked in a sterilizing fluid after washing, rinsed and stored in the cubicle, together with a selection of individually packaged snacks and vacuum-packed soft drinks.
Other centres vary in their degree of hygienic practice. The centre employing the sterile diet has its own housekeepers working in the LAF kitchen.
Information for home
At S Hospital, children may occasionally be discharged when their neutrophil count is >1x10E9/L. As this is below the normal range of 2.5- 7.5x10E9/L, some care with food is still necessary. Advice is given on ensuring food is as fresh as possible and refrigerated as necessary, not damaged or overripe, that food should be prepared in clean condition and that any food requiring cooking must be cooked thoroughly. Take-away food is not encouraged.
The Manual of Dietetic Practice offers similar advice, but states that no soft or raw eggs should be used, fruit and vegetables should be skinned and chilled cabinet foods should be avoided.
Three centres included literature for patients going home.
One or more of these centres advises against the following foods:
Poultry, cold meat, shellfish, raw eggs, soft and blue cheeses, dried fruit, raw vegetables, fresh cream and tap-water.
Dietary supplements
At S Hospital, commercial tube feeds and ready-prepared sip feeds without additional ingredients are used wherever possible to avoid contamination. Feeds are stored and prepared if necessary in a special feed unit under very clean conditions. The bottle or carton should be opened in the cubicle and either refrigerated in a sealed container for up to 24 hr or discarded if not used immediately. Prior to opening, bottles of prepared feed must be kept refrigerated. Information on the specific use of supplements was not received from other centres.
Table 2
Method Number of centres Comment
Main kitchen
Conventional cooking
Reheat in microwave oven .
11 centres
1 centre Diet cook generally follows detailed instructions
Cook chill 1 centre Only up to day of transplant
Ward kitchen 2 centres One used for BMT food preparation only
Gamma-irradiated/tinned food prepared in LAF uni 1 centre Sterile diet used for BMT patients
Discussion
Although the design of the survey provides only a limited amount of information, that which was received demonstrates that the level of restriction varies enormously between centres. The differences appear to be based on availably facilities and the individual views of staff. This is the case at S Hospital, where there are two closed cubicles available on the ward and very accommodating catering staff. Stricter measures have not been deemed necessary by the haematology team in the past. The use of LAF units as opposed to closed cubicles has decreased in popularity due to financial constraints and more effective antibiotic therapy. Studies have shown that total isolation can lead to low morale and poor appetite (Driedger & Burstall, 1987) and may not be more successful in reducing infection rates /Yates & Holland, 1973) when appropriate antibiotics are used.
Bacterial contamination
is by far the commonest cause of food poisoning with
· Salmonella causing 80-90% of cases in the general population, followed by
· Clostridium perfringes and
· Staphylococcus aureus.
High risk foods
( those which support multiplication of pathogens in the state they are to be eaten) are listed as cooked meat and poultry, dairy products, cooked eggs and egg products, shellfish and cooked rice.
Raw vegetables
have also been implicated as a source of infection for immunosuppressed patients from
· Pseudomonas aeruginosa
· Escherichia coli and
· Klebsiella species
(Shooter et al 1971; Kominos et al. 1972; Mutton et al 1980)
Contamination may occur during preparation of salad vegetables suggesting a need for scrupulous kitchen practice.
Bacterial testing of food
in US centres tend to be carried out only in LAF environments (Dezenhall et al, 1987) and was taken into account in only some of the centres surveyed here. The microbiology department at S Hospital does not feel that foodborne pathogens are an important source of infection in BMT patients and does not carry out routine microbiological testing of food.
One classification of the food to be “high risk”
Driedger et Burstall (1987) classified food according to bacterial levels and found the following foods to be “high-risk”: salads, fresh fruit and vegetables, non pasteurized dairy products and prepared snacks, desserts and condiments.
The number of organism that must be swallowed by a patient for intestinal colonization varies according to antibiotic therapy and the underlying disease. Animal studies have shown that in lowered resistance, only 10-100 organisms are needed for colonization, compared with 1 000 000 organisms in unimpaired resistance ( Van der Waajj et al 1972). After antibiotic therapy the intestine may be colonized with new pathogens after relatively few organisms have been ingested (Remington et Schimpff, 1981). The optimal temperature for multiplication of bacteria is 37 degree C and multiplication is rapid between 20 and 50 degree C. Food should be kept below 10 degree C or above the critical temperature 63 degrees C. Above this temperature, bacteria can no longer multiply. The Manual of Dietetic Practice recommends a minimum core temperature of 70 degrees C.
Ovens should be preheated
to a minimum temperature of 200 degrees C to raise the temperature of the food quickly. If food is to be boiled, e.g. vegetables, the water should be boiling before food is added to it.
Pressure-cooking is a good choice as long as the food is served immediately after cooking.
The use of microwave ovens
to cook food for BMT patients remains controversial. Their use was mentioned by only one centre surveyed here, which used microwave oven only for reheating cooked food. Microbes may only be inactivated in the presence of water, so dry foods may not be cooked effectively by microwave (Vela et Wu, 1979). In addition, Page et Martin, 1978, found that the survival
· Escherichia coli and
· Streptococcus cerevisiae on the inner surfaces of microwave oven was high when compared with the same organism in food.
Therefore, it is essential to disinfect the oven, especially if used for immunocompromized patients.
Fruuin et Gethertz (1982) found that bacteria were not killed as effectively by the rapid increase in temperature in microwave cooking as in conventional cooking, where food is held at high temperature for a long time.
However, Dreyfuss et Chipley (1980) found that microwave ovens had a destructive effect on Staphylococcus aureus due to radiation, in addition to the thermal effects found on conventional ovens.
There has been little documented evidence on the use and effectiveness of “clean” diets. Generally, there are four different levels of restriction.
Recently established centres in a US survey ( Dezenhall et al 1987) tended to use a modified ward diet ( normal diet excluding fruit and vegetables) and four centres had changed from sterile diet to a low-bacteria or modified ward diet. Reasons for the move towards less strict dietary procedures included limited availability of individual portions of sterile foods, lack of standardized recipes and low patient acceptance of autoclaved foods.
Preisler et al (1987) found a sterile diet afforded little or no advantage over a low-microbial diet and Yales et Holland (1973) showed a decreased incidence of Pseudomonas infections in both patients on a sterile diet and on a low-microbial diet.
Naiseef et Maki (1981) stated that it was possible for the simple measure of providing well-cooked food to provide considerable protection against endogenous infection caused by hospital acquired organisms.
Pizzo et al (1982) found that food selection became the focal point for patient frustration and also affected patient compliance with other medical procedures. A wider food selection added pleasure and variety to patient meals especially children.
Conclusion
Following the survey of current practice, discussions between the consultant haematologists, oncologists, microbiologists, ward staff, catering staff and dietitian reviewed the advice given to BMT patients at S Hospital. Several other factors were taken into account.
(1) There had been no record of food related infections in any immunosuppressed patient at the hospital.
(2) It was felt that the restrictions imposed by the clean diet made it difficult for the children to enjoy their food.
(3) It was felt that any advice given to patients undergoing BMT should be extended to any child undergoing chemotherapy as they would all be immunocompromised to some extent. Practically, this would be possible with new guidelines.
(4) The temperature of the food served from the ward trolley is regularly monitored to be higher than 63 degrees C. and therefore it was felt unnecessary to provide individual meals.
As a result. the advice now given is more in line with a more relaxed diet used in other centres for use at home. The advice sheet is given to all new patients on the oncology ward at the start of their treatment. The guidelines are to be continued on discharge.
Evaluation of patient acceptance and infection rates following the implementation of these guidelines will be carried out in the future.
( Appendix 1,2,3, ei ole kirjoitettuna tässä)
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