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In people with thyrotoxicosis caused by taking thyroid hormone medication, the rise in active thyroid hormone (FT3) is smaller and less proportional to the increase in precursor hormone (FT4) than in...
In people with thyrotoxicosis caused by taking too much thyroid hormone medication, the brain's control system for thyroid hormone levels behaves differently than in people whose thyroid gland...
People taking synthetic thyroid hormone (levothyroxine) for thyroid conditions show lower levels of a specific enzyme activity that converts T4 to T3 in the body, compared to people whose thyroid...
People taking synthetic thyroid hormone after thyroid removal have higher levels of FT4 but similar levels of FT3 compared to people with overactive thyroid glands due to Graves' disease or toxic...
When the THRB protein is removed from a specific type of pituitary cell in the lab, more THRA protein binds to the DNA region that controls the Tshb gene.
In a laboratory cell line derived from pituitary tissue, removing both versions of the thyroid hormone receptor prevents the hormone T3 from suppressing the production of Tshb mRNA, even when T3 is...
In a laboratory cell line derived from pituitary tissue, removing the thyroid hormone receptor beta prevents T3 from suppressing the production of Tshb mRNA, while removing receptor alpha does not,...
When thyroid hormone levels are slightly above normal, heart failure risk does not increase and may be slightly lower; when levels are much higher, heart failure risk increases. This suggests heart...
People with consistently elevated TSH levels above 5.5 mIU/L due to insufficient thyroid hormone replacement have a higher risk of developing heart failure over time, and the risk increases further...
Long-term use of too little or too much thyroid hormone medication is linked to a higher risk of developing heart failure, with the risk increasing the longer the imbalance lasts. After five years,...
In adults taking thyroid hormone medication, consistently having too much hormone in the blood—measured by very low TSH or high free thyroxine—is linked to a higher chance of developing heart failure.
Adults on thyroid hormone replacement therapy who consistently have very high TSH levels (above 20 mIU/L) are at significantly higher risk of developing heart failure over time compared to those with...
In certain benign tumors of the pituitary gland that overproduce TSH, the lack of thyroid hormone receptors prevents thyroid hormone from signaling the tumor to stop releasing TSH, leading to...
In certain pituitary tumors that overproduce TSH, the genetic instructions for thyroid hormone receptors are present and readable, but the receptors themselves are not made, suggesting a problem...
In tumors that produce excess TSH hormone, the proteins that respond to thyroid hormones are not detectable, even though the genetic instructions to make them are present. This suggests a problem in...
Eating 150 grams of cooked Brussels sprouts every day for four weeks does not change the levels of thyroid hormones in the blood of healthy adults.
In some people with autoimmune thyroiditis, the immune system's attack on the thyroid gland can lead to either an overactive or underactive thyroid, depending on how much damage has occurred and at...
In autoimmune disease, the immune system produces antibodies that target the body's own molecules and tissues.
Prolonged stress-related hormonal signaling can reduce the ability of the immune system to maintain balance, which may lead to a higher likelihood of autoimmune conditions.
Periodic fasting is associated with lower levels of inflammation in the body, which may occur because eating less frequently reduces exposure to food-derived antigens and activates cellular cleanup...
When the gut barrier is compromised, certain proteins in food called lectins that resemble thyroid proteins may trigger the immune system to produce antibodies that mistakenly target the thyroid...
Giving synthetic thyroid hormone externally raises levels of thyroid hormone in the blood and makes an existing overactive thyroid condition more severe.
Chemicals called glucosinolates found in cruciferous vegetables can reduce the uptake of iodine by thyroid cells, which may lead to decreased production of thyroid hormones.
Bile salts enhance the conversion of the thyroid hormone T4 into the more active form, T3, in tissues outside the thyroid gland, leading to higher levels of T3 in the blood.