Salivary Glands

Salivary Glands

Major glands
* Parotid: so-called watery serous saliva rich in amylase, proline-rich proteins
o Stenson’s duct
* Submandibular gland: more mucinous
o Wharton’s duct
* Sublingual: viscous saliva
o ducts of Rivinus; duct of Bartholin

Minor glands
* Minor salivary glands are not found within gingiva and anterior part of the hard palate
* Serous minor glands=von Ebner below the sulci of the circumvallate and folliate papillae of the tongue
* Glands of Blandin-Nuhn: ventral tongue
* Palatine, glossopalatine glands are pure mucus
* Weber glands

Functions
* Protection
o lubricant (glycoprotein)
o barrier against noxious stimuli; microbial toxins and minor traumas
o washing non-adherent and acellular debris
o formation of salivary pellicle
+ calcium-binding proteins: tooth protection; plaque
* Buffering (phosphate ions and bicarbonate)
o bacteria require specific pH conditions
o plaque microorganisms produce acids from sugars

Functions

* Digestion
o neutralizes esophageal contents
o dilutes gastric chyme
o forms food bolus
o brakes starch
* Antimicrobial
o lysozyme hydrolyzes cell walls of some bacteria
o lactoferrin binds free iron and deprives bacteria of this essential element
o IgA agglutinates microorganisms
* Maintenance of tooth integrity
o calcium and phosphate ions
+ ionic exchange with tooth surface
* Tissue repair
o bleeding time of oral tissues shorter than other tissues
o resulting clot less solid than normal
o remineralization
* Taste
o solubilizing of food substances that can be sensed by receptors
o trophic effect on receptors

Embryonic development
* The parotid: ectoderm (4-6 weeks of embryonic life)
* The sublingual-submandibular glands: endoderm
* The submandibular gland around the 6th week
* The sublingual and the minor glands develop around the 8-12 week
* Differentiation of the ectomesenchyme
* Development of fibrous capsule
* Formation of septa that divide the gland into lobes and lobules

Serous cells
* Seromucus cells=secrete also polysaccharides
* They have all the features of a cell specialized for the synthesis, storage, and secretion of protein
o Rough endoplasmic reticulum (ribosomal sites-->cisternae)
o Prominent Golgi-->carbohydrate moieties are added
Secretory granules-->exocytosis
* The secretory process is continuous but cyclic
* There are complex foldings of cytoplasmic membrane
* The junctional complex consists of:
o Tight junctions (zonula occludens)-->fusion of outer cell layer
o Intermediate junction (zonula adherens)-->intercellular communication
o Desmosomes-->firm adhesion

Mucous cells
* Production, storage, and secretion of proteinaceous material; smaller enzymatic component
-more carbohydrates-->mucins=more prominent Golgi
-less prominent (conspicuous) rough endoplasmic reticulum, mitochondria
-less interdigitations

Formation and Secretion of Saliva
* Primary saliva
o Serous and mucous cells
o Intercalated ducts
* Modified saliva
o Striated and terminal ducts
o End product is hypotonic

Macromolecular component
* Synthesis of proteins
* RER, Golgi apparatus
* Ribosomes RER posttranslational modification (N- & O-linked glycosylation) Golgi apparatus Secretory granules
* Exocytosis
* Endocytosis of the granule membrane

Fluid and Electrolytes
* Parasympathetic innervation
* Binding of acetylcholine to muscarinic receptors
o Activation of phospholipase IP3 release of Ca2+ opening of channels K+, Cl- Na+ in
o K+ and Cl- in
o Also another electrolyte transport mechanism through HCO3-
* Noepinephrine via alpha-adrenergic receptors
o Substance P activates the Ca2+

Myoepithelial cells
* One, two or even three myoepithelial cells in each salivary and piece body
* Four to eight processes
* Desmosomes between myoepithelial cells and secretory cells
* Myofilaments frequently aggregated to form dark bodies along the course of the process

Myoepithelial cells
* The myoepithelial cells of the intercalated ducts are more spindled-shaped and fewer processes
* Ultrastructurally very similar to that of smooth muscle cells
* Functions of myoepithelial cells
o Support secretory cells
o Contract and widen the diameter of the intercalated ducts
o Contraction may aid in the rupture of acinar cells of epithelial origin

Intercalated Ducts
* Small diameter
* Lined by small cuboidal cells
* Nucleus located in the center
* Well-developed RER, Golgi apparatus, occasionally secretory granules, few microvilli
* Myoepithelial cells are also present
* Intercalated ducts are prominent in salivary glands having a watery secretion (parotid).

Striated Ducts
* Columnar cells
* Centrally located nucleus
* Eosinophilic cytoplasm
* Prominenty striations
o Indentations of the cytoplasmic membrane with many mitochondria present between the folds
* Some RER and some Golgi, short microvilli
* Modify the secretion
o Hypotonic solution=low sodium and chloride and high potassium
* Basal cells

Terminal excretory ducts
* Near the striated ducts they have the same histology as the striated ducts
* As the duct reaches the oral mucosa the lining becomes stratified
* Goblet cells, basal cells, clear cells.
* Alter the electrolyte concentration and add mucoid substance.

Ductal modification
* Autonomic nervous system
* Striated and terminal ducts
* Modofication via reabsorption and secretion of electrolytes
* Final product is hypotonic
* Rate of salivary flow
o High: Sodium and chlorine up; potassium down

Connective tissue
* Fibroblasts
* Inflammatory cells
* Mast cells
* Adipose cells
* Extracellular matrix
o Glycoproteins and proteoglycans
* Collagen and oxytalan fibers
* Blood supply

Nerve supply
* No direct inhibitory innervation
* Parasympathetic and sympathetic impulses
* Parasympathetic are more prevalent.
* Parasympathetic impulses may occur in isolation, evoke most of the fluid to be excreted, cause exocytosis, induce contraction of myoepithelial cells (sympathetic too) and cause vasodilatation.
* There are two types of innervation: Epilemmal and hypolemmal
* beta-adrenergic receptors that induce protein secretion
* L-adrenergic and cholinergic receptors that induce water and electrolyte secretion

Hormones can influence the function of the salivary glands. They modify the salivary content but cannot iniate salivary flow.

Age changes
* Fibrosis and fatty degenerative changes
* Presence of oncocytes (eosinophilic cells containing many mitochondria)

Clinical Considerations
* Obstruction
* Role of drugs
* Systemic disorders
* Bacterial or viral infections
* Therapeutic radiation
* Formation of plaque and calculus

Salivary Glands.ppt

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Examination of Urine

Examination of Urine
By:Terry Kotrla, MS, MT(ASCP)
Professor
Austin Community College


Urine Color

* Normal urine color ranges from pale yellow to deep amber — the result of a pigment called urochrome
o B vitamins turn urine an eye-popping neon yellow BUT may also indicate liver disease.
o porphyria, a disease that affects your skin and nervous system, turns urine the color of port wine.

Urine Color

* Most changes in urine color are harmless and temporary and may be due to:
o Certain foods – beets may turn urine red
o Dyes in foods/drinks
o Supplements – vitamins
o Prescription drugs
* Unusual urine color can indicate an infection or serious illness .

Suggested Colors

* pale yellow (straw)
* light yellow
* yellow
* green-yellow (olive)
* red-yellow
* red
* red-brown
* brown-black
* black
* milky

Examples of Urine Color

Urine Clarity

* During the visual inspection, the MLT observes the urine's and determines how clear it is (its clarity).
* Urine clarity refers to how clear the urine is.
* Terms used: clear, slightly cloudy, cloudy, or turbid.
* “Normal” urine can be clear or cloudy.
* The clarity of the urine is not as important as the substance that is causing the urine to be cloudy.

Urine Clarity

* Substances that cause cloudiness but that are not considered unhealthy include:
o mucous,
o sperm and prostatic fluid,
o cells from the skin,
o normal urine crystals, and
o contaminants (like body lotions and powders).
* Other substances that can make urine cloudy (such as red blood cells, white blood cells, or bacteria) indicate a condition that requires attention.

Examples of Urine Clarity

Urine Color and Clarity

* Urine color and clarity can indicate what substances may be present in urine.
* Confirmation of suspected substances is obtained during the chemical and microsopic examination.

Chemical Examination

* Reagent strips are used only once and discarded.
* Testing
o Perform within 1 hour after collection
o Allow refrigerated specimens to return to room temperature.
o Dip strip in fresh urine and compare color of pads to the color chart after appropriate time period.
o Instruments are available which detect color changes electronically

Using Reagent Strips

* BRIEFLY dip the strip in urine.
* Colors are matched to those on the bottle label at the appropriate times.
* Timing is critical for accurate results.

Reagent Strips

Glucose

* Presence of glucose (glycosuria) indicates that the blood glucose level has exceeded the renal threshold.
* Useful to screen for diabetes.

Bilirubin

* Bilirubin is a byproduct of the breakdown of hemoglobin.
* Normally contains no bilirubin.
* Presence may be an indication of liver disease, bile duct obstruction or hepatitis.
* Since the bilirubin in samples is sensitive to light, exposure of the urine samples to light for a long period of time may result in a false negative test result.

Ketones

* Ketones are excreted when the body metabolizes fats incompletely (ketonuria)

Specific Gravity

* Specific gravity reflects kidney's ability to concentrate.
* Want concentrated urine for accurate testing, best is first morning sample.
* Low – specimen not concentrated, kidney disease.
* High – first morning, certain drugs

Blood

* Presence of blood may indicate infection, trauma to the urinary tract or bleeding in the kidneys.
* False positive readings most often due to contamination with menstrual blood.

Ph

* pH measures degree of acidity or alkalinity of urine

Protein

* Presence of protein (proteinuria) is an important indicator of renal disease.
* False negatives can occur in alkaline or dilute urine or when primary protein is not albumin.

Urobilinogen

* Urobilinogen is a degradation product of bilirubin formed by intestinal bacteria.
* It may be increased in hepatic disease or hemolytic disease

Nitrite

* Nitrite formed by gram negative bacteria converting urinary nitrate to nitrite

Leukocytes

* Leukocytes (white blood cells) usually indicate infection.
* Leucocyte esterase activity is due to presence of WBCs in urine while nitrites strongly suggest bacteriuria.

Normal Values

* Negative results for glucose, ketones, bilirubin, nitrites, leukocyte esterase and blood.
* Protein negative or trace.
* pH 5.5-8.0
* Urobilinogen 0.2-1.0 Ehrlich units

Handling and Storage of Strips

* Handling and Storage
o Keep strips in original container
o Do not touch reagent pad areas
o Reagents and strips must be stored properly to retain activity
+ Protect from moisture and volatile fumes
+ Stored at room temperature
o Use before expiration date

Procedure

* Dip strip briefly, but completely into well mixed, room temperature urine sample.
* Withdraw strip.
* Blot briefly on its side.
* Keep the strip flat, read results at the appropriate times by comparing the color to the appropriate color on the chart provided.

Sources of Error

* Timing - Failure to observe color changes at appropriate time intervals may cause inaccurate results.
* Lighting - Observe color changes and color charts under good lighting.
* QC - Reagent strips should be tested with positive controls on each day of use to ensure proper reactivity.
* Sample - Proper collection and storage of urine is necessary to insure preservation of chemical.

Sources of Error

* Testing cold specimens - would result in a slowing down of reactions; test specimens when fresh or bring them to RT before testing
* Inadequate mixing of specimen - could result in false reduced or negative reactions to blood and leukocyte tests; mix specimens well before dipping
* Over-dipping of reagent strip - will result in leaching of reagents out of pads; briefly, but completely dip the reagent strip into the urine

Examination of Urine

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Blood Collection

Blood Collection

An overview of the process involved in collecting donor blood

Donor Screening
* Starts with the donor and first impressions are critical
* Clean, well lit donation facility from waiting room to collection area
* Pleasant, professional staff who can ask the appropriate questions, observe and interpret the responses, and ensure that the collection process is as pleasant as possible

Blood Bank versus Blood Center
* Confusion exists and terms are sometimes used inappropriately
* Blood bank in a hospital is also known as the transfusion service, performs compatibility testing and prepares components for transfusion
* Blood Center is the donation center, screens donors, draws donors, performs testing on the donor blood, and delivers appropriate components to the hospital blood bank

Standards, Regulations, Governing Bodies
* Strict guidelines exist and inspections are performed in both blood centers and blood banks to ensure the safety of the donors and patients
* Some or all of the following agencies may be involved:
o AABB – American Association of Blood Banks
o FDA – Food and Drug Administration
o CAP – College of the American Pathologists
o JCAHO - Joint Commission on the Accreditation of Hospital Organizations
o NCCLS – National Committee for Clinical Laboratory Standards

Donor Screening
* Medical History based on a standardized questionnaire obtains critical information about the donor’s health and risk factors which may make it unsafe for donation
* Physical Exam which includes blood pressure, temperature, pulse and screen for anemia are performed to ensure donor is healthy enough to donate.
* Two goals of screening
o Protect the health of the potential donor
o Protect the health of the potential recipient

Donor Registration
* Donor signs in
* Written materials are given to the donor which explains high risk activities which may make the donor ineligible
* Donor must be informed and give consent that blood will be used for others unless they are in a special donor category
* First time donors must provide proof of identification such as SS#, DL#, DOB, address and any other unique information.
* Repeat donors may be required to show DL or some other photo ID

Frequency of donation
* Whole blood or red blood cells 8 weeks
* Plateletpheresis – up to 24 times/year
* Plasmapheresis– once every 4 weeks, can be done twice a week
* Granulocytes

Medical History
* A thorough history is obtained each time
* Standardized universal questionnaire is used
* Questions are asked that are very intimate in nature but are critical in assessing HIV or HBV risks
* Medications the donor taking are present in plasma, may cause deferral
* Infections the donor has may be passed to recipient, may be cause for deferral

12 Month Deferral
* Any intimate sexual relations with HIV positive, HBV positive, hemophiliacs, drug users or individuals receiving drugs/money for sex.
* Recipient of blood, components or blood products such as coagulation factors
* Sexually transmitted disease-if acquired indicates safe sex not practiced and donor at risk for HIV and HBV
* Travel to malarial endemic country

Temporary Deferrals
* Certain immunizations
o 2 weeks -MMR, yellow fever, oral polio, typhoid
o 4 weeks -Rubella, Chicken Pox
o 2 months – small pox
* Pregnancy – 6 weeks upon conclusion
* Certain medications
o Proscar/Propecia, Accutain – 1 month
o Avodart – 6 months
o Soriatane – 3 years
o Tegison - permanent

Permanent Deferrals
* HIV, HBV, or HCV positive
* Protozoan diseases such as Chagas disease or Babesiosis
* Received human pituitary growth hormone
* Donated only unit of blood in which a recipient contracted HIV or HBV
* Was the only common donor in 2 cases of post-transfusion HIV or HBV in recipient
* Lived in a country where Creutzfeld-Jacob disease is prevalent
* Most cancers except minor skin cancer and carcinoma in-situ of the cervix
* Severe heart disease, liver disease

Helpful Hint
* Permanent deferral – any member of high risk group such as: HIV/HBV/HCV pos, drugs/sex for money, cancer, serious illness or disease, CJD, Chagas disease, Babesiosis
* 12 month deferral – sex with any high risk group, any blood exposure, recipient of blood/blood products, STD, jail/prison, rabies vaccine after exposure, HBIG, malaria
* Have to memorize: medications and vaccinations

Self-Exclusion
* Two stickers
o “Yes, use my blood”
o “No, do not use my blood”
* After interview the donor will place the appropriate bar coded label on the donation record
* If “no” selected the unit is collected, fully tested, but not used for transfusion
* Allows donors who know they are at risk to “save face” if pressured to donate by friends and family

Donor Categories
* “Allogeneic”, “homologous” and “random donor” terms used for blood donated by individuals for anyone’s use
* Autologous – donate blood for your own use only
* Recipient Specific Directed donation – donor called in because blood/blood product is needed for a specific patient
* Directed Donor – patient selects their own donors
* Therapeutic bleeding – blood removed for medical purposes such as in polycythemia vera. NOT used for transfusion.

Auto/Directed Blood Labels
Donor Categories
* Safest is autologous, blood is your own, no risk of disease acquisition
* Most dangerous is Directed Donor, you select a donor who may, unknown to you, be in a high risk category but feels obligated to follow through and donate

Blood Collection
* Materials used are sterile and single use.
* Most important step is preparing the site to a state of almost surgical cleanliness.
* Bacteria on skin, if present, may grow well in stored donor blood and cause a fatal sepsis in recipient
* Use 16-17 gauge needle to collect blood from a single venipuncture within 15 minutes
* Collect 450 +/- 45 mLs of blood

Donor Reactions
* Syncope (fainting)
o Remove needle immediately
* Hyperventilation
o Have donor rebreathe into paper bag.
* Nausea/vomiting
* Twitching/muscle spasms
* Hematoma
* Convulsions – rare, get immediate assistance
* Cardiac difficulties

Post-Phlebotomy Care
* Donor applies pressure for 5 minutes
* Check and bandage site
* Have donor sit up for few minutes
* Have donor report to refreshment area for additional 15 minutes of monitoring

Post-Phlebotomy Instructions
* Eat/drink before leaving
* Wait until staff releases you
* Drink more fluids next 4 hours
* No alcohol until after eating
* Refrain from smoking for 1 hour
* If bleeding continues apply pressure and raise arm
* Faint or dizzy sit with head between knees
* Abnormal symptoms persist contact blood center.
* Remove bandage

Testing Donor Blood
* CANNOT rely on previous testing
* Records must be kept for 5 years

Serological Testing
* ABO/D typing
* Antibody Screen – if positive, ID antibody, cannot make plasma products
* Antibodies to other blood group antigens which are present in the donor may react with recipient red cells resulting in a reaction.

Disease Testing
* Disease testing include:
o HBsAG
o HBc
o HCV
o HIV 1&2
o HTLV I/II
o RPR
o NAT for HIV-1, HCV & WNV

Results of Testing
* Tests for disease markers must be negative or within normal limits.
* Donor blood which falls outside these parameters must be quarrantined.
* Repeat testing, if still abnormal must dispose.

Transfusion Service Testing
* The only repeat testing required is:
o ABO on red cell products
o D typing (IS) on D negative red cell products
* Plasma products (FFP, CRYO, PLTS) do not require any testing.
* Donor samples must be stored at 1-6C for at least 7 days after transfusion
o ADSOL unit transfused today must save sprig for one week
o Many facilities will pull a sprig from each donor during processing and save all sprigs for 49 days, regardless of expiration of unit

Summary
* Blood collection starts with screening of the donor to:
o Ensure they are healthy enough to donate
o Ensure they do not have transmissible diseases
* Many organizations set standards and monitor all aspects of blood collection and administration.
* Collection of blood must be done in such a manner as to ensure sterility of the component.
* Testing of donor blood includes serological testing for ABO/D typing, antibody screening, and testing for markers indicating infection.
* The blood supply is NOT safe, only careful screening and testing can prevent, as much as possible, disease transmission.

Blood Collection

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