Thyroid Thyroid & Thyroid Thyroid Diseases Diseases
Submitted By Anushka Sharma XI ‘D’
Submitted to Ms. Lakshmi Peter Biology Teaher Teaher
This is to erti!y that Anushka Sharma" a student o! lass XI ‘D’ has suess!ully om#leted the researh on the belo$ mentioned #ro%et under the guidane o! Ms. Lakshmi Peter during the aademi year &'()*(+.
Signature o! Biology Teaher
Signature o! Prini#al
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Acknowledgeme nt
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rimarily I $ould like to thank ,od !or being able to om#lete this #ro%et $ith suess. Then I $ould like to e-#ress a dee# sense o! thanks gratitude to our #rini#al Dr. Jaishree Kanwar" !or her o*ordination in e-tending e/ery #ossible su##ort !or the om#letion o! this #ro%et. This #ro%et $ould not been !easible $ithout the #ro#er guidane o! biology teahers Ms. Lakshmi Peter & Dr. Shelly Chaturvei $ho guided me throughout this #ro%et in e/ery #ossible $ay. 0er suggestions and her instrutions has ser/ed as the ma%or ontributor to$ards the om#letion o! the #ro%et. I also thank my #arents !or their moti/ation su##ort. I must thank my lassmates !or their timely hel# su##ort !or om#ilation o! this #ro%et. Last but not the least" I $ould like to thank all those $ho had hel#ed diretly or indiretly to$ards om#letion o! this #ro%et.
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Anushka Sharma 1lass*XI ‘D’
Contents (. Thyro yroid ,lan ,land d2222 222222 222 22222 222222 222 22222 222222 22 &. 0orm 0ormon ones es o! Thyroi yroid d ,lan ,land2 d222 2222 2222 222. 2..2 .222 2222 222 2 4. Thyro Thyroid id Disorde Disorders2 rs2222 22222 22222 222222 222222 222222 222.. .. 4.( 0y#e y#erthyro yroidism22222222222222222 4.& 0y#ot y#oth hyro yroidis idism m222 2222222 222222 2222 222 22222 22222. 2... 6. 0isto istorry222 y22222 222 22222 222222 2222 222 22222 222222 222 22 3. 7ther ther Anima imals2 ls22222 22222 22222 222222 2222 222 22222 22222 2 ). 1ase 1ase Stud Study y...22 ..2222 2222 2222 2222 2222 2222 2222 2222 2222 22.. .... +. Bibl Biblio iogr gra# a#h hy222 y22222 2222 2222 2222 2222 2222 2222 2222 222. 2... ..
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The Thyroid Glan Gland d
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he thyroid gland is the largest endorine gland loated anterior to the thyroid artilage o! the laryn- in the nek. It is om#osed o! t$o lobes $hih are loated on the either sides o! the trahea. Both the lobes are interonneted $ith a thin !la# o! onneti/e tissues alled isthmus. The thyroid gland is om#osed o! miroso#i s#herial sas" the !olliles held together by loose onneti/e tissue" the stromal tissue. Beside ontaining blood a#illaries" the stromal tissues ontains small luster o! s#eiali9ed #ara!olliullar ells or ‘1’ ells. :ah thyroid !ollile is om#osed o! !olliular ells" enlosing a a/ity. The !olliles are !illed $ith a homogenous substane alled olloid" om#osed o! glyo#rotein" thyroglobulin. The thyroid gland an store enough hormones in the olloid to su##ly the body !or about t$o months.
The human thyroid as viewed from the front with arteries visi!le"
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The thyroid as it may !e seen from from a #osterior view from !ehind the trachea"
%ormones of Thyroid Gland The thyroid gland serets three hormones; !hyr"#ine or tetra$i""thyr"#ine
Setion o! thyroid under miroso#e (.>olliles? &.>olliular ells? 4.:ndothelial ells
Thyro-ine
!hyr"#ine '!*) and !rii""thyr"#ine '!+) are usually onsidered together under the name thyr"i h"rm"ne '!,) beause they ha/e similar e!!et on the target ells. T6 and T4 ontain !our and three atoms o! iodine res#eti/ely? there!ore" they are named so. They are synthesi9ed by attahing iodine to the amino aid tyrosine by en9ymati en9ymati ation. T4 is sereted in smaller amounts but is more ati/e than T6. 0o$e/er T6 is on/erted to T4 by the remo/al o! one iodine in li/er" kidney and some other tissues. The thyroid gland is the only endorine gland that stores its hormones in large @uantity. The hormone is stored in the olloid that !ills the !olliles and is released into the
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blood $hen re@uired. The T6 and T4 #er!orm the !ollo$ing !untions;
The structural formula and the s#ace 'lling model of triiodothyro(ine)T3*
The structural formula and the s#ace 'lling model of thyro(ine)T4*
a= They regulate the metaboli metaboli rate o! the body thus" maintains basal metaboli metaboli rate
e= They hel# in maintaining maintaining body tem#erature tem#erature by regulating regulating heat #rodution. #rodution. != They regulate regulate the urine out#ut out#ut by ontrolling ontrolling the $orking $orking o! kidneys. kidneys. g= They They simulate simulate tissues tissues Am#hi!ian di!!erentiation? hene" they hel# +etamor# hosis in metamor#hism o! tad#ole into adult !rog. !hyr"%al%it"nin '!C!). The thyroalitonin or alitonin in!luenes the alium homeostasis in the body. It then lo$ers the alium le/el by inhibiting the release o! alium ions !rom the bones. Thus" alitonin ats antagonistially to the ation o! #arathyroid hormone on alium metabolism.
-ynthesis of the thyroid hormones as seen on an individual thyroid follicular cell"
%y#erthyroidism 0y#erthyroidism is a ondition o! the thyroid. It ours $hen the thyroid makes too muh T 6" T4" or both.
Causes A /ariety o! onditions an ause hy#erthyroidism. -raves isease" an autoimmune disorder" is the most ommon ause o! hy#erthyroidism. It auses antibodies to stimulate the thyroid to serete too muh hormone. ,ra/es’ disease ours more o!ten in $omen than in men. It tends to run in !amilies" $hih suggests a geneti link. 7ther auses o! hy#erthyroidism inlude; •
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e-ess iodine" a key ingredient in T6 and T4 thyroiditis" or in!lammation o! the thyroid" $hih auses T6 and T4 to leak out o! the gland tumors o! the o/aries or testes benign tumors tumors o! the thyroid thyroid or #ituitary #ituitary gland
-igns & -ym#toms 0igh amounts o! T6" T4" or both an ause an e-essi/ely high metaboli rate. This is alled a hy(er meta/"li% state. hen in a hy#er
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metaboli state" you may e-#eriene a ra#id heart rate" ele/ated blood #ressure" and hand hand tremors. tremors. Co Cou may also s$eat a lot and de/elo# de/elo# a lo$ tolerane !or heat. 0y#erthyroidism an ause more !re@uent bo$el mo/ements" mo/ements" $eight loss" and" in $omen" irregular menstrual yles. isibly" the thyroid gland itsel! an s$ell into a goiter" $hih an be either symmetrial or one*sided. :yes may also a##ear @uite #rominent" $hih is a sign o! e-o#hthalmos" a ondition that’s related to ,ra/es’ disease. 7ther sym#toms o! hy#erthyroidism inlude; •
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inreased a##etite ner/ousness restlessness inability to onentrate $eakness irregular heartbeat di!!iulty slee#ing !ine" brittle hair ithing hair loss nausea and /omiting breast de/elo#ment de/elo#ment in men men
/llustration de#icting enlarged thyroid that may !e associated with hy#erthyroidism
The !ollo$ing sym#toms re@uire immediate medial attention; •
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di99iness shortness o! breath loss o! onsiousness onsiousness !ast" irregular heart rate
0y#erthyroidism 0y#erthyroidism an also ause atrial !ibrillation" a dangerous dangerous arrhythmia that an lead to strokes" as $ell as ongesti/e heart !ailure.
Diagnosis .
The ommon signs o! hy#erthyroidism; •
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$eight loss ra#id #ulse ele/ated blood #ressure #rotruding eyes enlarged thyroid gland
7ther tests may be #er!ormed to !urther e/aluate your diagnosis. These inlude;
1holesterol test Cour dotor may need to hek your holesterol le/els . Lo$ holesterol an be a sign o! an ele/ated metaboli rate" in $hih your body is burning through through holesterol holesterol @uikly. @uikly. T6" !ree T6" T4 These tests measure ho$ muh thyroid hormone
Triglyeride test Cour triglyeride le/el may also be tested. Similar to lo$ holesterol" lo$ triglyerides an be a sign o! an ele/ated metaboli rate.
Thyroid san and u#take This allo$s your dotor to see i! your thyroid is o/erati/e. In #artiular" #artiular" it an re/eal re/eal $hether the entire thyroid thyroid or %ust a single single area o! the gland is ausing the o/er ati/ity.
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Eltrasound Eltrasounds an measure the si9e o! the entire thyroid gland" as $ell as any masses $ithin it. Dotors an also use ultrasounds to determine i! a mass is solid or ysti.
1T or MI sans A 1T or MI an sho$ i! a #ituitary tumor is #resent that’s ausing the ondition.
%ow to treat hy#erthyroidism Mediation Antithyroid mediations" suh as methima9ole
adioati/e iodine adioati/e iodine e!!eti/ely destroys the ells that #rodue hormones. 1ommon side e!!ets inlude dry mouth" dry eyes" sore throat" and hanges in taste.
Surgery A setion or all o! your thyroid gland may be surgially remo/ed. Cou $ill then ha/e to take thyroid hormone su##lements to #re/ent hy#othyroidism" $hih ours $hen you ha/e an underati/e thyroid that seretes too little hormone. Also" /eta$/l"%kers suh as #ro#ranolol an hel# ontrol your ra#id #ulse" s$eating" an-iety" and high blood #ressure
hat you can do to im#rove sym#toms :ating a #ro#er diet" $ith a !ous on %al%ium and s"ium" is im#ortant" im#ortant" es#eially in #re/enting hy#erthyroidism.
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0y#erthyroidism an also ause your bones to beome $eak and thin" $hih an lead to osteo#orosis. Taking /itamin D and alium su##lements during and a!ter treatment an hel# strengthen your bones.
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%y#othyroidism 0y#othyroidism is a ondition $here your thyroid gland does not make enough thyroid hormone. Lo$ le/els o! thyroid hormone inter!ere $ith the body’s ability to #er!orm normal metaboli !untions suh as e!!iient use o! energy !rom !ood #roduts" regulation o! many hemial reations in the body" and maintenane o! healthy ells" bones and musles" to name a !e$.
Causes The most ommon auses are surgial remo/al o! your thyroid" autoimmune diseases" and radiation treatment.
Surgial emo/al This may be neessary to treat hyperthyroidism" or tumors o! the thyroid gland. 0y#othyroidism $ill our $hen the entire gland is remo/ed.
Autoimmune Diseases These diseases ause the #rodution o! antibodies that attak your thyroid gland. Autoimmune thyroiditis" $hih an a##ear suddenly or de/elo# o/er se/eral years" is more ommon in $omen. 0ashimoto’s thyroiditis and atro#hi thyroiditis are the most ommon ty#es.
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adiation Treatment adiation treatment !or 0odgkin lym#homa and aners o! the head and nek an in%ure the thyroid gland. I! this ours" the gland annot #rodue enough enough thyroid thyroid hormone hormone to kee# your your metabolism running smoothly. adioati/e iodine
ther Causes of %y#othyroidism 1ongenital 0y#othyroidism Some hildren are born $ithout a thyroid gland or they may ha/e one that doesn’t !untion #ro#erly.
iral or Autoimmune Thyroiditis hen antibodies or /iruses attak your thyroid" thyroid hormones an leak out. Sometimes all o! the thyroid’s hormones are released into your blood at one time. hen hen this ha##ens" ha##ens" sym#toms o! thyroid e-ess e-ess or hy#erthyroidism our.
Mediations Lithium
Pituitary Disease The #ituitary is the master gland that signals the thyroid ho$ muh hormone it needs to #rodue. I! the #ituitary is damaged by trauma" stroke" or tumor" the signal to release thyro-ine an sto#. This auses the thyroid to sto# making thyroid hormone.
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Fot :nough or To Too Muh Iodine The thyroid gland needs iodine to make T4 and T6. Iodine had to be obtained in the diet. Too little iodine an ause hy#othyroidism and" ironially" too muh iodine an blok the thyroid’s ability to make thyroid hormone.
In!iltration Diseases like amyloidosis an ause the thyroid to beome o/er$helmed by abnormal #roteins $here the ells annot !untion normally.
Grou#s Grou#s at %igher isk for %y#othyroidism %y#othyroidism The !ollo$ing grou#s are at a greater risk !or de/elo#ing hy#othyroidism; •
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$omen o/er age 3'. #eo#le $ith autoimmune autoimmune diseases or a #arent #arent or grand#arent grand#arent $ith an autoimmune disease. #eo#le gi/en gi/en radioati/e radioati/e iodine or radiation radiation thera#y thera#y #eo#le treated treated $ith antithyroid antithyroid mediation mediation those $ith a history o! radiation to the nek and u##er hest #eo#le $ith a #artial thyroidetomy
hat Are the -ym#toms There are no sym#toms that are uni@ue to hy#othyroidism. There may be no sym#toms sym#toms early in the disease disease #roess. Long Long standing" untreated untreated hy#othyroidism an ause obesity" %oint #ain" heart disease" and in!ertility. 7ther sym#toms an inlude; •
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inreased sensiti/ity to old onsti#ation
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de#ression !atigue $eakness hea/ier menstrual !lo$ brittle hair and and nails
I! le!t untreated" the !ollo$ing sym#toms an our; •
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hoarseness #u!!iness #u!!iness o! the !ae" !ae" hands" and !eet !eet slo$ed s#eeh dereased taste and smell thin eyebro$s thikened skin oma <alled Gmy-edema omaH=
%ow /s /t Diagnosed Cour dotor !irst onduts a #hysial e-am and re/ie$s o! your medial history. This an re/eal any #roedures like thyroid surgery or radiation treatments onneted to hy#othyroidism. >amily history might re/eal a lose relati/e $ith autoimmune disease. Mediation history might be #ositi/e !or drugs" drugs" suh as lithium lithium and amiodarone amiodarone that an an ause the ondition. Beause hy#othyroidism is most o!ten !ound in $omen o/er age 3'" some dotors ad/oate thyroid !untion sreening !or this grou#. Dotors also may suggest sreening $omen o! hildbearing age. Blood tests also are ommon. These inlude; •
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thyroid !untion tests; T6" T4E and TS0 tests !or #ituitary !untion; TS0 holesterol <an be ele/ated= 1B1
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#rolatin <an <an be ele/ated= ele/ated= eletrolytes
In hy#othyroidism" T6 is lo$ and TS0 is high. This means the #ituitary is sending more TS0 to stimulate the thyroid" but the thyroid does not res#ond. A lo$ TS0 indiates the #ituitary may be the ause o! hy#othyroidism.
Treatment Treatment #tions for %y#othyroidism %y#othyroidism A ommon treatment is to re#lae thyro-ine $ith a s#ei!i syntheti thyroid hormone
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shakiness or tremors #al#itations insomnia inreased a##etite
Diets rih in soy and high !iber an inter!ere $ith le/othyro-ine absor#tion. Mediations and su##lements also an redue absor#tion. These inlude; •
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alium su##lements iron su##lements holestyramine aluminum hydro-ide <#resent in some antaids=
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%istory
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istorial re!erenes to $hat $e no$ kno$ as the thyroid gland arise early in medial history. In Ayur/edi mediine medi ine"" the book Sushruta Samhita $ritten Samhita $ritten about (3'' B1 mentions the disease goitre as ,alaganda along $ith its treatment. In ()'' B1 the 1hinese $ere using burnt s#onge and sea$eed !or the treatment o! goiters
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the ha#ter JDe boioJ o! his magnum o#us" he desribes se/eral #harmaologial #harmaologial and surgial surgial ures" ures" some o! $hih no$adays no$adays are are rea##raised as sienti!ially e!!eti/e. It $as not until (6+3 that ang 0ei anatomially 0ei anatomially desribed the thyroid gland and reommended reommended that the treatment o! goitre should be dried thyroid. Paraelsus Paraelsus"" some !i!ty years later" attributed goitre to mineral im#urities in the $ater.
In modern times" the thyroid $as identi!ies in ()3) by the anatomist Thomas harton. In ()3) Thomas harton named the gland the thyroid" meaning shield" as its sha#e resembled the shields ommonly used in Anient ,reee. In (8'8" Theodor Koher !rom S$it9erland $on the Fobel Pri9e in Mediine G!or his $ork on the #hysiology" #athology and surgery o! the thyroid gland.
Thyroid in ther ther Anim Animals als
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he thyroid gland is !ound in all /ertebrates /ertebrates.. In !ish" it is usually loated belo$ the gills and is not al$ays di/ided into distint lobes. 0o$e/er" in some teleosts teleosts"" #athes o! thyroid tissue are !ound else$here in the body" assoiated $ith the kidneys" s#leen" heart" or eyes.
In tetra#ods tetra#ods"" the thyroid is al$ays !ound some$here in the nek region. In most tetra #od s#eies" there are t$o #aired thyroid glands * that is" the right and le!t lobes are not %oined together. 0o$e/er" there is only e/er a single thyroid gland in most mammals mammals"" and the sha#e !ound in humans is ommon to many other s#eies. In lar/al lam#reys lam#reys"" the thyroid originates as an e-orine e-orine gland" gland" sereting its hormones into the gut" and assoiated $ith the lar/as !ilter*!eeding a##aratus. In the adult lam#rey" the gland se#arates !rom the gut" and beomes endorine" endorine" but this this #ath o! de/elo#ment de/elo#ment may may re!let the e/olutionary origin o! the thyroid. >or instane" the losest li/ing
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relati/es o! /ertebrates" the tuniates tuniates and and Amphioxus Amphioxus"" ha/e a struture /ery similar to that o! lar/al lam#reys
Characteristic changes in the facial skin of a 6a!rador etriever with hy#othyroidism
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Case Study
7i!liogra#hy 20
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G7ther An AnimalsH. Thyroid. &+ ul. &'(). ( Aug &'(). htt#s;NNen.$iki#edia.orgN$ikiNThyroid htt#s;NNen.$iki#edia.orgN$ikiNThyroidO7theranimalsQ O7theranimalsQ G0istoryH Thyroid. &+ ul. &'(). ( Aug &'() htt#s;NNen.$iki#edia.orgN$ikiNThyroidO0istory N$ikiNThyroidO0istory Q htt#s;NNen.$iki#edia.org Sharma" Dr. .P. .P. Comprehensive Comprehensive Biology Class XI ; 1hemial 1oordination and Integration" (''6" (''3. Etiger Etiger"" obert obert D. G0y#oth G0y#othyro yroidi idismH smH.. :nylo# :nylo#Rdi Rdiaa Britann Britannia ia.. :nylo# :nylo#Rdi Rdiaa Britannia 7nline. :nylo#Rdia Britannia In." &'(). eb. eb. &( ul. &'() htt#s;NN$$$.britannia.omNsieneNhy#othyroidismQ G0y# G0y#er erth thyr yroi oidi dism smH. H. 4 Aug. ug. &'( &'() ) htt#;NN$$$.healthline.omNhealthNhy#erthyroidismQ
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