Histology #6 (Digestive) Flashcards

Question

Barret's esophogus vs. Chroic brinchitus

Answer 1

BOTH = indicated by metaplasia but different types Barretts - intetsinal metaplasia (statified squamous to columnar intestinal epithelium) Chronic mronchitus - sqamous metaplasia (psudostratfied columnar to squamous) Image - see the metaplasia

Answer 2

Location - ONLY found in the small intestine - Located centrally in teh villi within the lamina propria - Function of SI = absorb Nutrietnst (does so because of the villi) - lacteals = Lymphatic vessels in the Villi Function - absorb dietary fats and fat soluble vitamens + affect gut immune repsone by facolitatiing the transport of antigen and antigen presenting cells

Answer 3

Once fat and nutrients enters the lacteal --> fat/nutrients will go through the lymphatic system --> fat/nuteints will enter the blood stream --> go to cells that need nutrients Image - shows lacteal

Answer 4

Overall - dysfuction in lacteal aka Waldmann disease Congetical disorder with no known cause Diagnosed before 3 YO Charetized by Pitting Edema - Have enlarged lacteals leading to disrputed absorption of nuetrients - Dilated lacteals = Lymph fluid leaks back into the small intestine

Answer 5

1. Nutrien definceycies because can't absorb fats and vitaments 2. Protein loss (albumin loss) --> decreases onctotic pressure leading to lage of lymhati vessels = lose albumin 3. Edema (primary in limbs) because less portein blocking = decrease oncotic pressure 4. Abdominal discomfert - swelling of the peracardium and fluid in the chest

Answer 6

Due to an underlying condiion that block or damage lymphatic vessels in the intestines - Get dilation of the villi Caused by: 1. Tumors 2. Inflamatory disease (ex. chrons) 3. Traima or lymphatic infections (Ex. Whipple's disease + TB)

Answer 7

1. Long term low fat diet 2. Diuretics (help with edema) 3. Albumin infusion (increases onctotic pressire and reduces edema) 4. Removal of diseased protion of intestine if localized 5. adress the promary cause of lyphatic pbstruction IF have Secondary Intestinal Lymphangiectesia

Answer 8

Function - absorb water + electrolytes + vitaments - Also produces mucus lubricating the intestinal surface Divided into 4 layers: Mucosa --> submucosa --> muscularis Priria --> serosa

Answer 9

Overall - motor disorder of the colon Have missing nevre cells in colon = problems with passing stool Mainly affects newborns - No bowl movment in 48 hours + green/brown vomit + swolen Abdomen Diagnosis - use a rectal biopsy Untreated = can lead to constipation + bowl obstrcution

Answer 10

Colon Aganglionosis - no entertic ganglion cells in the submucosal/ no myenteric nerve plesxus of colon Motor disorder of colon = caused by falure of nueral crest cells to migrate during intestinal developmet - Agalionic segemnt of teh colon fails to relax = causes functional obstruction - Intestinal contents build up ebhind the obstruction

Answer 11

Angaglionic segment - absence of submucosal and myteic ganglion cells + have submucosal and mysenteric nerve enlargment to over compensate (black arrows)

Answer 12

See ganglion cells (black arrows) +submucosal nerves that are narrow (white arrows)

Answer 13

Use actylcholineestrase IHC - Can diagnosis with IHC Normal = Actylchontersatse highlighst sparse thin nerves vs. Hirschsprung it hiughlights abdendet course nerves (shows never enlargment) Image - Hirschsprung Histology - Nomrla = less brown

Answer 14

Overall - cancer of the epithelial cells from colonic mucosa Risk factors: 1. Age 2. Family history 3. Genetc predispotion 4. Illness (Ex. IBD) 5. Envirnment/lifestyle (Ex. Alchol + smoking)

Answer 15

Symptomes: 1. Rectal bleed 2. Abdominal Pain 3. Anemia

Answer 16

1. Colonscopy --> AFTER do multiple biospies of the suspected lesion 2. Barium enema - barium passed into bowels + X-Ray 3. CT colonoscopy

Answer 17

Accumilation of multiple geneic mutations over time Three major pathways: 1. Chromosomal Insatbility (CIN) - APC (tumor supressore) mutations - Intiated by mutations in tumor supressor gene 2. Mircosailite insability - Muations in Mismatch repair mutations 3. CpH Island methylaion (CIMP) - BRAF muations (mutation in oncogene) - Leads to serrated Polyps

Answer 18

Mustaions are largley aqured sporatically (70% of pateints) 3-5% have well defined inherited mutations - Ex. Lynch syndrome --> gemrinline mutations in MMR genes - Family adenomatous polyposis (FAP) --> germiline mutaion in APC 25% have family history but no well defined mutation

Answer 19

Healthy colon mucosa = have gladsn in regular pattern Adenocarcimao - fewer glands + irregular patterns Image - poorly differentared tumor (no glandular space)

Answer 20

1. Sugery (used fro localized/earl stage) 2. Chemotherapy if advanced (Ex. 5-Floururicil) 3. Immunotherapy (ant PD1, anti-VEGF etx)

Answer 21

Colon Adenocarcinoma is typically graded by level of glandular formation Well diferentation (95% of tumor gland fomring) vs modertaly differentites (>50%) vs. Poor differentated (<50%) Image - Well differentated tumor - has lots of glandular looking space but different shapes + some empty and some have cells

Answer 22

Have the right and left lobe - seperated by a ligament Lobes are divived by the haptic veins --> divsions ate furtehr dvided into 8 segments that house the hepatic lobules - All 8 segments have same functiion but different blood supply

Answer 23

Liver has dual blood supply 75% of the blood comes from the protal vein (deoxgynated blood) --> liver filters the blood

Answer 24

Liver = considered a gland that secreted proteins and hromones 1. Detoxification - removes toxins + bacteria + old RBCs (immunologic suveilnce) 2. Bile production - Bile is used for the breakdown of fats in SI 3. Storage of vitame s + mineral + glucose 4. Blood coagulates 5. Makes albumin - controsl oncotic pressure

Answer 25

1. Portal triad 2. Central Vein 3. Bile Duct 4. Space of Disse

Answer 26

Overall - Basic fucnational unit of liver structure Functiion - maintains metabolsim + detoxification Hexoganal shape with central vein at the center Composed of Hepatocytes arranged in plates - Hepatocytes have a radial pattern - Radial pattern = Ensures proper blood flow and niterinet absorption Portal traid located at the corner of the hexoginal lobule

Answer 27

Composed of: 1. Hepatic artery - supplies oxygen-rich blood from the heart 2. Portal vein - carries nuterint rich blood from the digestive organs 3. Bile duct - transports bile produced by hepatpcytes Blood and bile flow in opposite directions - Blood flow towards the cebtral vein ; bile flows towards the bile duct - Direction of flow = important for liver function --> ensures porper porcessing of nutreints and waste

Answer 28

See cetral vein

Answer 29

See Potal vein + Hepatic artery + Bile duct Portal vein and hepatic arteru = made up of endothlial cells BUT can distiguish between them because the veins are larger in diamter/thinner and the arteries are thicker - Bile duct = cuoidal epithelial cells

Answer 30

Location - At the cnter of each hepatic lobule and lined with a single layer of endothelial cells - Central vein = surroinded by the protal traid Function - central vein receives oxygen and nucetrint rich blood at the sinusoids from the portal vein and hepatic artery Central vein coeleces into the hepatic vein --> hepatic vein carries deoxygeated blood back to the IVC Image - See central vein at the bottom and protal traid at the top

Answer 31

Left - see sinuisoidal a the bottom - blood goes through them to the Central vein Right - see pattern of hepatpcytes

Answer 32

Lined with Cholangiocytes - simple cuboidal epithelum cells Emerge from canacals of hering --> get larger in diamater --> branch to the irght and left hepatic duct --> go to the common hepatic duct --> goes to others in GI Function - stores and passes bile Small bile ductules join together to form left and irght hepatic ducts Passes through the liver and collects bile as liver produces it Chalangiocytes have many functions in bile modoification - Chalangiocytes = chnage the bile composition through secretion and reabsorption of water and electrocytes + immine cells. barrier for bile

Answer 33

See cholgiocytes lining the bile duct

Answer 34

Overall - Space between the sinusoidal endotheluum and hepatcytes Function - Trasnport of lymphatic fluid to lymphatic capilaiers in the protal traid - Important for the uptake of macromolecules + bile salts + nuetrients + ions Blood goes from the portal triad to the central vein --> sinuisoids have fenestartes (open space that allow macromolcules to go to the space of disse) Space of Disse = face the basolaternal surface of hepatcytes = allows hepatpcytes to uptake macromolecules

Answer 35

Seen in EM See endothelial cells + hepatocytes ; space between is the space of Disse In space = have Dentrotic cells + reticular fibers + liver stem cells + Stelate cells

Answer 36

1. Hepatocytes 2. Kupffer Cells 3. Stellate Cells

Answer 37

Main functional cells of he liver Shape - Polygonal shapes + arranged in interconecting plates - Bile canaliculi between adjacent cells = allows bile to flow - Have microvili Involoved in Main function of the liver: 1. Endocrine and exocrine secretion 2. Synthesis of proteins and lipids 3. Metabolism 4. Detoxification 5. Activation of immune cells

Answer 38

Left - See arangment of hepatcytes with iterlated plate sbranching from cnetral vein Right - see have many mitocorndria + many ER + rpund central nucelus

Answer 39

Overall - Macrophages located in the walls of hepatic sinuisoids Shape - irregular and varibale shape + oval/indented Cell surface conatins microvilli + slender projections that extend in all directons Function - removes pathogens, compounds, and debris through phagocytosis

Answer 40

Traid blie = taken up by the phagcytic Kupffer cells = can be used to idetfy them Rigt - see iregular shape + proejctsiing coming from kupfer cells to the sinusoid space

Answer 41

Overall - Mesenchymal cells located in the space of Disse Shape - Star hsaped contaning multiple lipid vacuoles in cytoplasm + irregular nuclei Functions: 1. Vitamen A storage 2. Liver development and regernations 3. Response to hepatic injury - If have toxins/pathigens = stellate cells make ECM and collegen (could lead to fibrosis)

Answer 42

Left - Identofy Stelate cells based on lipid vaculaues circule structure) Right - see vacule is lighter yellow + irregu;ar nuceli

Answer 43

yellow color = lipfusion on Hepatocytes H ane E = older hepatpcytes ; can have also bile pigment o heptocytes

Answer 44

1. Endocrine = hormones going to the blood stream 2. Exocrine = digestive enzymes going to the small intestine

Answer 45

Endocrone function = localizes at the islates of langerhands Islets are composed of: Alpaha cells - secrete glucagon Beta Cells - Secrete Insulin Delta Cells - Secrete somatostatin F Cells - Secrete Pancreyotc polypeptides

Answer 46

Function - Prodice Glucogan in reponse to low blood glucose - fasting response + respond after excersize Make up 20% of islet cels H/E - stain pink due to glucogan granuales

Answer 47

Overall - increases glucose in the body 1. Glycogenolysis - stimulates the liver to cnvert glycogen to gucose 2. Gluconogensis - Stimulates the liver to increase amino acid uptake from the blood to make glucose 3. Lipolysis (form of gluconeogensis) - stimulates the liver and adipose tissue to convert stores trglycerides to free fattery acids and glyceral to then make glycerol and then make glucose in the liver

Answer 48

Produce inculin - When have food in inetstine --> hae release of gastrointestinal hormones --> leads to insulin production by beta cels - Secretion is stimulated by increase blood glucose 75% of islet cels (most numerous cell in islets) H/E = stain blue because of insulin granial Lose of function --> get tyoe 1 diabetes

Answer 49

Overall - decreases blood glucose - Inhibit the release wgen blood glucose decreases 1. Stimulates glycosis (get breakdown of Glucose to get ATP) 2. Stimulate glycogensis (Covert glucose to glycogen) 3. Inhibits glycogenolysis and gluconeogensos 4. Promotes triglyceride and protein syntehsis - creates a negative feedback loop to mkae sure blood surgar doesn't drop too low

Answer 50

Facilitates glucose uptake - Occurs in skelatal mucles + Adipose tissue Mechaism is largkey unknown - Insulin activates tyrosin kinase --> kinase move glucose trasnprter GLUT4 from storage vesicles in the cytoplasm to the plasma membrane to take in glucose from the envirnment

Answer 51

Alpha cells = in the periphery (pink cels) ; beta cells are on the inside of the sphere under the pink layer

Answer 52

Overall - Produce Somatostatin - Release is stimulated by increase in glucose + ghrelin in the stomach Cooridnates insulin + glucose secretion to maintain homeostasis 4% of islet cells

Answer 53

Overall - Inhibits release of glucogan + insulin Somatstin = activate somatostatsin receptors on alpha and beta cells coupled to inhibitory GPCR --> supresses electrical stimularion --> inhibits exicytosis of granualswith glucose or insulin

Answer 54

Aka Gamma cells/F cells Produce Pancreotic Polypeptide - Produces after eating+ in response to fasting - Sceretion stimulated by intestinal hormones cholecystoknin + secrtin + gastron 1% of islaet cells Use Immunoflourence to see

Answer 55

Regulates appetitie to reduce hunger levels - Singals to the brain through the vegas nerve to decrease hunger levels after eating and slow digestion Slows digestion - Decreases the rate of gastric emptying - Decreases pancreati exocrine secretion - Decreases Gallblader contracton

Answer 56

see immunostains for different sections Alpha cells stain for glucogon Beta cells = stain for insuline

Answer 57

Function - Used for breaking down food into constutent molecules for absorbption - Pancreatis makes many products that we need to digets things Produces pancreitic juice that conatins digetsive enzymes + biocarbinate + water - Products are released into the duadenum of teh SI Exocrine = uses Acinar Cells

Answer 58

Secrete digestive enzymes - Take complex biomilciles and breaks them down into end products we can absrobs Secrete: 1. Amylase - breask down starches into simple surgars 2. Protease - breaks down proteins into amino acids (Ex. Trypsin) 3. Lipases - break donw fats to fatty acids and lycerol 4. Nucelases - Break donw nucleic acids into nucleotides

Answer 59

Have many ER for protein synthesis - Acinar cells = main cells that make digetsive zymes = protein factpries = have many ER (light blue in image) Acinar makes the enzymes in inactive form --> Stores inactive enzmes in Zymogen granuaals (purple in image) - Zymogen has inactive enzyme precursory --> precursor is released via excocytosis when stimulated by CCK to the duadenum

Answer 60

Sceret Biocarbinate and Water Bicarbinated is scerted into the diadenum to nuertilzie HCl in acidic chyme - When acidic chyme is in the dusenum scertrin homrone is released which stimultae bicrabinate release - Bicarbinate protects the small intestone from stomach acid + maks H more aklinine to optomize pH for digestive zymes to function - Controled by secrtin hromone

Answer 61

Uses Acinar Cells + epithelial cells + centracinar cells Glandular tissue = tubular acinar function Acinar cells = oretneted regu;larley around the lumen in glands ; centroacinar cells are the first cells in interclated ducts

Answer 62

There is no muscle in the pancreus to put fluid into teh SI --> center of the acinar and endothlialc els make water to push fluid put

Answer 63

Acinar cells = have apical granals (stains pinked) + pyrimidal shaped Centracinar Cells = pale + Low cuboidal cells

Answer 64

Shows the islets + blood flow in the islets - Blood flows form the center of the islet to the periphery (drains to the portal vein) - Capilaries put hormones throughout the body (focus on capilaries) Capilaries - see fenetratsed capilaried running rthough the endocrine tissue + running hrough the islets Acinar cells = darer purpel cells ; stain protein products rain ; pyrimindal shape Centroacinar cells = more pale + cuboidal + first ductal cell in the system (form interclated ducts)

Answer 65

Pacreus = divided into lobules Lobules = cluster f acinar and islets in connective tossue capsule (Blue in image) Lobules often seoprate during processing (see on irght image)

Answer 66

Ductal cells = exicrine cells Veins + arteries + nerves + lymphatics = ofte fowllow connective tissue in pancreus 1. Epithelial ductual cells - start as cuboidal and trasnition to columnar cells along path to main pancreatic duct - Also have more connective tossie as go tpwards main duct 2. Interclated Ducts - most proximal part - start as cuboidal and trasnition to columnar cells along path to main pancreatic duct 3. Intralobular ducts (D in image) - Join acini within a lobule 4. Interlobule ducts - Connect lobules

Answer 67

Sectrein is produced in the duodenum in presnece of acids --> secrtin binds to secrtin recpetors on memebrane of centroacinar cells --> binding leads to GPCR signaling --> get secretion of biocrabinate and water from centroacinar cells

Answer 68

Centeroacinar Cells line the interclated ducts Stimulation of the centroacinar cells stiulates the intercalted ducts Centeroaconar cels --> intercladed ducts --> Pancreatic ductal system

Answer 69

Cholecytoskinin (CCK) = prduced by the duodenum - Seretion of acinar cells = stimulated by CCK CCK has a direct and indirect effect on the secretion of acinar cells - Direct - CCK binds to CCK receptors on acinar cells (CCK recpetors may or may not be found in humans) - Indirect - CCK --> affects through vegal afferent fibers --> get actylcholine --> stimulates acinar cells to release digestive enzymes

Answer 70

Have head then neck then body then tail Have the main duct thabranches and goes through the pancreaus to faclitate movement of pancreotic juices to teh SI

Answer 71

Exocrine - digetive zbymes relased by acinar cels + ductual cells relased HCO3- - Acinar cell - Digetsive enzymes - Ductal cells - HCO3- Endocrone - isle cells that have alpha + beta+ delta cells - Hormone cells - Glycagon + insulin + Somatostatin Image - see exocrine vs. endocrine pancreus

Answer 72

Pancreus regulates glucose metabolism - Produces digetsive enzymes and hromones important for glucose and lipid metabolism High blood suar = pancreus releases insulin -- release will bring glucose into cells and convert glucose to glycogen in the liver - Insulin lowers blood sugar levels

Answer 73

Chronic disrpuiion of insulin sugnlaing + chronic hyperglycemia Get hyperglycemia - high blood glucose levels Symptmes - Thirst + fatigure + weight loss + blurred vision Untreated diabetes leads to - circulatpry disorders + renal failire + blindness + gangrene + stroke + heart attack Tteatments - diet change + insulin (ex. pills)

Answer 74

Autoimmune disease Cause = unknonw but has envirnmental and genetic components Have loss or inactivity of beta cells - Immune system attacks beta cells that produce insulin --> detsroyes beta cells --> pancreus can't make insulin --> results in high blood glucose level because glucose is no longer being brought into the cells

Answer 75

Top image = helathy (have islets + beta cells) Left - dark blue circles are lymphocytes influtrating islates = detroy beta cells Right - more scere case of diabetes - immune cells took ove (no more beta cells)

Answer 76

Metabolic disorder Caused by Lifestyle factors + genetic predisposition Have decrease in insulin secretion OR tissues fail to respond to insulin - Insuoin binds to receptors but can't activate GLUT4 --> glucose can't enter the cell --> glucose builds up outside the cell --> reulst with high blood glucose levels histology - charcterized by amyloid deposits (uildup of plaues in the pancreus because of misfolded proteins)

Answer 77

Have premature activation of Tyrsinogne to trypsin in acinar cells in the pancreus (activation should occur in teh duadenmum) - Trypisn activates several pancreatc enzymes --> leads to autog=digestion of the pancreus End = have self digestion of the pancreus

Answer 78

1. Serine proteae inhibitore (SPINK1) - normally inhibites the convesion of trypsinogen to trypsin ; kazal type 1 - Muation or absense of function of SPINK1 = get prmeature activation of tyrpin - Mutation alone will not cause ALSO need genetic modifcation or envirnmental trigger to cause 2. Cytsic fibrosis trasnmemrane conductase regulator - ATP gated ion chanle that meduaes passive dffusion of Cl- and HCO3- - Mutation/dysfunction chanel = get abnormal secretion of digestive enzymes = failure to wash away active trypsin to pancreatic duct = get inflamation - One mutation in chanel won't cuase ALSO need other genetic modifcation

Answer 79

Acute inflamation of the pancreus - pancreus is swollen for short period of time Leading cuase of gastrointestinal related hspilization in the US Mortality rate is 3%-20% Causes: 1. Gallstones + Achol Use + hypertiglyceridemia - glyceride = lipid that prpvides energy -> too much in blood causes acute pancreatitus

Answer 80

Condition 1 - increase intraductal pressure - Caused by Gall stones Condition 2 - High intrcelllular Ca2+ levels --> facilitaties activation of trypsin - Caused by Alchol use + hypertriglyceridemia = get disrupts calcium homeostasis

Answer 81

Top = Normal Other 2 images - see intestinal damage in acuate pacreatitise - Have leukocyte invasion + edema

Answer 82

More svere - have cells with nerosis + hemorage

Answer 83

Form of pancreatic cancer involved in the organ's exocrine cells that release digestive enzymes Risk factors: 1. Chonic pancreatitus 2. Diabetes 3. Inherited DNA mutaions 4. Obesity 5. Smoking Causes 90% of all pancreus cancer 13% 5 year survival rate (bad prognosis because detected late) 19% of tumors are detected at late stage >50% of tumoes have systemic metastses

Answer 84

1. PanLN 2. IPMN 3. MCN

Answer 85

Two teir grading system for precursors (low and high grade dysplasia) PANIN and Cyt=stic = transition from columnar cells with basolary orineted nuceli to irregular shape cells with displased nuceli (have cytologic and morphologic chnages)

Answer 86

Pancreatoc intraepithelial neoplasia Microscopic size (Small) Found in intralobular ducts Causes 90% of PDAc cases Commonly found in the head of the pancreus

Answer 87

Intraductal papilary mucinous neoplasm Characterized as growths of the ductal epithelium Columnar cell tye Macroscopic size <10% of PDAC Comonlu found in head and neck fo pancreus

Answer 88

Mucinous cystic neoplasm Does NOT invove panreus dctal system (not in communcation with pancreotic ducts) Charcterized by ovarian type stroma (maybe due to estrogen receptors on origin cells) Macroscopic size <3% of PDAC Commonly found in pancreus body and tail (distal regions)

Answer 89

Goes from normal --> low grade lesions --> high grade --> PDAC

Answer 90

Whipple - remice head of pnacreus + duadenum + bile duct + gall bladder + part of stomach Distal pancreatectomy - remove body of pacreaus + tail of pancreus + spleen Total pancreatcomy - remove pancres + spleen + gallbladder + common bile duct + some of SI + some the stomach - Patients are given artifical hormones and digetsive enzymes

Answer 91

1. Extermal Beam Radaitio therapy 2. Intesity-modulated radiation therapy (IMRT) 3. Stereotactic Body radiation theapry (SBRT)

Answer 92

Can give chemothearapy drugs Examples: 1. Gemcitabime 2. 5-flourouracil 3. Irontecan 3. Alubimin bound pcitaxel 4. Cisplatin 5. Paclitaxel

Histology #6 (Digestive) Flashcards

(121 cards)