The Bionic Human test 2

  1. how different types of cells make up the human body
  2. heart cells
    contract to pump blood
  3. what makes a muscle cell different from a bone cell
    different genes are turned on and off in each type of cell.
  4. Extracellular Matrix
    The majority of bone
  5. Chemical composition of bone
    70% inorganic 

    30% organic
  6. Bone mineral – hydroxyapatite
    contains calcium, phosphorous, oxygen; gives bone its rigidity and hardness & strength in compression.
  7. Bone collagen (type I)
    a structural protein, gives bone its flexibility (elasticity) and strength in tension; toughness.
  8. Osteoblasts
    produce and secrete bone matrix, i.e. collagen, subsequently mineralizing the collagen through enzymatic activity
  9. Osteoclasts
    bone resorption, i.e. “digest” bone that needs to be rebuilt, liberating important minerals in the process.
  10. Osteocytes
    osteoblasts become osteocytes after becoming trapped inside calcified bone. Some of the oldest cells in the body, > 25 years old!! They act as “sensors” feeling the forces in the bone through their numerous extensions.
  11. types of bone
    • cortical (or compact)
    • cancellous (or trabecular bone)
  12. Adult human skeletal mass consists of __% cortical bone and __% cancellous bone
    80, 20
  13. Osteoporosis
    • Characterized by:
    • 1. Increased bone porosity
    • 2. Reduction in bone mass
    • 3. Disruption of bone architecture

    • Cancellous bone is the most severely
    • affected.

    • Bone loss starts earlier in women (at
    • 35 years of age)

    • Osteoporosis is similar to the bone
    • loss caused in microgravity

    Ceramics (glasses, carbon)

    Natural polymers (both plant and animal derived)

    • Synthetic polymers (petroleum or natural gas
    • byproducts)
    Stainless Steels

    Cobalt-based alloys

    • Titanium-based alloys
    • -Very light with relatively high strength

    • Noble metals – Silver, Gold, Platinum
    • -Expensive, low strength, highly corrosion resistant

    Mercury – Dental amalgam
  16. chromium
    gives stainless steel its scratch and corrosion resistance
  17. nickel
    provides stainless steel with a smooth and polished finish
  18. molybdenum
    gives stainless steel greater hardness
  19. Low carbon content (denoted by L)
    desirable in stainless steel for corrosion resistance
    • Two common types
    • • Commercially pure (cp) titanium
    • – implants where high strength is not
    • required. (e.g. fiber metal)

    • Ti 6Al-4V ELI
    • – 6% Aluminum & 4% Vanadium

    • Advantages:
    • – Light weight & high strength
    • – Good corrosion resistance due to TiO2
    • solid oxide layer
    • – Non-magnetic (MRI safe)
  21. Osseointegration
    a strong bond of implant to bone achieved with titanium implants
  22. Shape memory alloys
    • Nickel-titanium alloys
    • – After the alloy is deformed, they snap back to their previous shape when heated.
    • – The phenomenon is called shape memory effect

    • NiTi (NiTinol) recovers virtually to any shape as long as the
    • deformation is within 10%

    • Advantages: biocompatible, does not calcify
    • Disadvantages: “expensive”, potential risk of fracture
    • Used in: blood vessel stents, aneurysm clips, orthopedics
  23. Copper Oxide Impregnated Textiles
    Impregnation or coating of cotton and polyester fibers with cationic copper

    • Potent broad-spectrum antibacterial, anti-viral, antifungal and anti-mite properties
    • – Anti Odor Footwear
    • – Anti-Aging Appearance Enhancing Satin Pillowcase
  24. Silver - antimicrobial coatings
    • Apparently interferes with
    • bacterial enzymes

    Used in wound dressings

    • Philadelphia: Alfred Barnes
    • developed a mild silver nitrate
    • antiseptic solution and
    • marketed the drug as Argyrol, a
    • treatment for gonorrhea
    Alumina (Al2O3) or Zirconia (ZrO2)

    • Hard (second only to diamond) and scratch
    • resistant

    Extremely biocompatible

    • Low friction and wear properties
    • – Good for joint bearings

    Zirconia is stronger than alumina

    Advantages: Strong, stable, wettable, no need to follow degradation products

    Disadvantages: Interface with bone or tissue is weak, low shock resistance, high modulus, catastrophic failures
    Mixture of tetracalcium phosphate and dicalcium phosphate anhydrous

    When mixed with water forms hydroxyapatite – the mineral that is present in bone and teeth

    Calcium phosphate cements are osteoconductive, bioresorbable, and do not produce any heat duringmhardening

    • Used as bone augmentation (in severely
    • osteoporotic bone) during fracture fixation
    Most successful and commonly used form

    • “pyrolysis” – thermal decomposition
    • – Occurs at high temp, with an inert gas (N or He)
    • – Instead of “burning,” the carbon “polymerizes” due to the
    • absence of oxygen

    • Often used as a coating material
    • – Preforms are coated, then machined and
    • polished before assembly
    • – Diamond plated grinders and tools are needed
    • because PyC is very hard
    • – Finish can be made very smooth

    • Very good blood-contacting properties

    • Used to coat
    • – Heart valve components
    • – Stents

    • Compatibility not perfect
    • – Anticoagulants needed
    • – Blood compatibility not completely understood

    • Other applications
    • – Joint components
    • – solid PyC parts are possible
    • The collagen in the tissues of vertebrates occurs in at least 10 different forms (type I – bone, skin, tendons; type II – nucleus pulposus, cartilage; type
    • III – heart valves)

    • Collagen also has an unusual AA sequence:
    • Gly-Pro-Xxx-Gly-Pro-(OH)-Xxx

    Glycine is every third residue and hydroxy-proline alternates with proline at every third residue.

    Collagen mechanically reinforces the extracellular matrix that primarily consists of proteoglycans
  29. Natural suture: cat(tle)gut
    Collagen based suture

    Derived from the submucosal layer of ovine small intestine or the serosal layer bovine small intestine "gut."

    • Treated with an aldehyde solution (gluteraldehyde?), which
    • cross-links and strengthens the suture and makes it more resistant to enzymatic degradation

    Surgical gut, plain: No further treatment

    • Surgical gut, chromic : treated with chromium salt
    • – absorption rate is slowed by chromium salt
  30. A herniated disc may be repaired......
    spacers or artificial discs
  31. Hydrogels
    A network of hydrophilic polymer chains dispersed in up to 99.9% water, i.e. mostly water --- similar to the body.

    Due to their significant water content, hydrogels have flexibility (mechanical properties) similar to cells, tissues and organs.
  32. Hydrophilic Surfaces
    • “Water-loving surface”. Water
    • tries to maximize contact with surface (spread out).

    Examples: Glass, hydrogels
  33. Hydrophobic Surfaces
    • “Water-fearing surface”. Water tries
    • to minimize contact with surface (beads up).

    Examples: Teflon, oily surfaces, lotus leaves
  34. What Could go Wrong with your Heart?
    Electrical system failure

    Vascular failure

    Valve failure

    Heart failure
  35. Normal EKG (PQRST) pattern
    Image result for Normal ECG (PQRST) pattern
  36. P
    Atrial contraction
  37. QRS
    Ventricle contraction
  38. T
    Ventricular Repolarization
  39. Causes of Electrical System Failure
    Prevent impulse generation in the SA node

    Inhibit impulse conduction
  40. heart
    Image result for the conduction system of the heart
  41. Development of Atherosclerotic Plaques
    Image Upload 1
  42. Surgical treatment for clogged arteries
    or atherosclerosis
    Angioplasty with Stenting

    Bypass surgery
  43. Diagnosis of Heart Failure
    • Echocardiogram, or “echo”
    • Ejection Fraction
    • Healthy heart = 60% or more
    • Heart failure = 40 % or less

    Electrocardiogram, or “EKG” or “ECG”

    Chest X-ray
Card Set
The Bionic Human test 2
test 2