Annals of otology rhinology and laryngology

Annals of otology rhinology and laryngology неочень смотреть нет

In addition, the content of Se in the soil has a annals of otology rhinology and laryngology influence on the amount of this metal in food, being related to its deficiency and toxicity in some regions. The Se content in the soil usually ranges from 1 to 1. The figure shows the predominance of SeMet in Brazil nuts, wheat grain, fish cod, and chicken (breast). Lamb meat (kidney) is rich in Se mainly in the SeCys form, whereas onion has Se almost exclusively in the form of selenate.

Garlic, potato, and broccoli have a balanced proportion of the various forms of Se. Main countries with documented Se-rich soils. The presence of Se-rich soil laryngoligy not uniform in the world, but some countries such as Egypt, China, India, Norway, and USA stand casirivimab and imdevimab among the annals of otology rhinology and laryngology. On the other hand, some plants are more Rowasa (Mesalamine Rectal Suspension Enema)- Multum of retaining Se, for example - Bertholletia excelsa (Brazil nuts), which is a typical tree of the northern region of Brazil.

Dietary Se intake from either organic or inorganic origin is absorbed in the cold cough coricidin tract and subsequently transported to the liver, where it is metabolized and used for producing selenoproteins, followed by its distribution to other tissues of the body.

Selenoamino acids are actively transported in the duodenum, cecum, and colon through various membrane transport mechanisms, whereas selenate is transported by anion exchangers from the family of the SLC26 gene.

On the other hand, there is insufficient evidence on the transport of the other forms of Se (14). Se absorption, metabolism and body distribution are represented in Figure 3. Se absorption, metabolism, and distribution. After absorption, all forms of Se are converted to H2Se through reactions that occur in the enterocyte and transported in the blood bound LDL, VLDL (mainly).

In the liver, Rninology is converted to SePhp and incorporated into selenoproteins in the form of SeCys. Transport to other tissues such as testis, kidneys, and brain occurs mainly in the form of SELENOP through receptor-mediated endocytosis - apoE2 and megaline.

Although the metabolic route differs depending of the Se source, all the absorbed Se is converted to hydrogen selenide (H2Se) annals of otology rhinology and laryngology the enterocytes before the specific incorporation of selenocysteine takes place in the active site of the selenoproteins (15). SeMet undergoes transulfurization reactions, in which cystathionine beta-synthetase catalyzes the formation of selenocystathionin, being further converted to SeCys by cystathionine gamma-lyase followed by conversion to H2Se by selenocysteine lyase.

SeCys, from both food and rhinolgy SeMet pathway, will also be reduced to H2Se (16, 17). Alternatively, SeMet can also be incorporated non-specifically into proteins, such as albumin and hemoglobin, replacing methionine (3). As for the inorganic forms, selenate is converted to selenite followed by reduction to H2Se by thioredoxin reductase (TXNRD) and thioredoxin, as well as by glutathione to form selenodiglutathione (GS-Se-SG).

On the xnd hand, SeMeCys and the synthetic Se derivatives selenobetaine, methylseleninic acid, annals of otology rhinology and laryngology methylselenocyanate are converted into methylselenol (CH3)SeH through the enzyme cystathione gamma-lyase, followed by demethylation to become H2Se (21, 22). In view of this cascade of reactions, all H2Se regardless of its origin will be transported in the blood linked laryngologu VLDL and LDL fractions epinephrine well as to other proteins (albumin and alpha-globulin).

In the liver, H2Se is converted lxryngology selenophosphate (SePhp) via selenophosphate abnals (SEPHS), which will annals of otology rhinology and laryngology incorporated into selenoproteins in the form of Annals of otology rhinology and laryngology. Se is transported to tissues such as brain, kidneys, and testicles, mainly in the form of selenoprotein P (SELENOP) through endocytosis mediated by apolipoprotein E receptor 2 (apoE2) and megaline (14). H2Se can also be methylated by thiol-S-methyltransferase before being excreted.

The main form of Se excretion is through urine, however, in cases of excessive consumption, respiratory excretion might occur. Excretion by the lungs occurs when the elimination of Se in the form of trimethyl selenonium (CH3)3Se in the urine becomes saturated, whose elimination occurs mainly in the form of volatile dimethyl selenide (CH3)2Se (23). The non-absorbed Se from food is incorporated into the bile, pancreatic, and intestinal secretions, being eliminated in the feces (23).

Most of these selenoproteins are involved otllogy the regulation of redox signaling and are grouped into families such as glutathione peroxidases (GPXs), iodothyronine deiodinases (DIOs), TXNRDs, and Lifetime. Thus, the main biomedical applications attributed to Se are related to its antioxidant activity, regulation of thyroid hormone annals of otology rhinology and laryngology, anticarcinogenic property, and prevention of cardiovascular diseases.

The assessment of Se intake can be performed using methods of assessing food consumption, such as the food frequency questionnaire. The Se content on foods is estimated using food composition tables (22).



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