Notesale: Turn your study into money

Document Preview

Extracts from the notes are below, to see the PDF you'll receive please use the links above

---

HEALTH, DISEASE, & DEVELOPMENT OF MEDICINES
1
...
communicable & non-communicable diseases
Non-Communicable: chronic – can’t be spread
Communicable diseases: can be spread
Pathogen: disease-causing microorganism – produce toxins: make you feel ill
Virus: Reproduce inside cells – destroy cell
Use cells to copy their DNA and to make more virus particles
3
...
pathogen:

virus
5
...
Spread & spread reduction
tuberculosis bacteria
stomach ulcers bacteria:
Airborne
helicobacter
It causes lung damage
It causes weakened stomach wall
Spread by oral transmission
– hydrochloric acid makes hole
Spread reduced by
isolation/
Spread by oral transmission
masks
Spread reduced by covering food/
good hygiene
Chalara ash dieback fungi
It causes leaf loss / bark lesions
Spread by wind – airborne
Spread reduced by
identifying/spraying trees

Malaria protist
It causes damage to blood/liver
Spread by female mosquitos:
carrier – suck blood & pass
plasmodium
Spread reduced by mosquito net/
change female DNA

7
...
STI
Chlamydia bacterium
Can only reproduce inside cells (like virus)
Can cause infertility, burning urination, thick yellow/green discharge, women: bleeding, men: testicle swelling
Spread by Unprotected sex / Infected fluid contact with mucous membranes
Spread reduced by condom / screening to be treated / abstinence / antibiotics
HIV virus
It causes mild flu symptoms / AIDS / white blood cell destruction
AIDS: when immune system deteriorates then fails – become very vulnerable to other infections
Spread by genital fluids / Unprotected sex / Infected mother to foetus / Sharing needles
Spread reduced by condom / screening + treatment / avoid body tissue injuring sex / sterilise needles
9
...
Plant chemical barriers – some used in human medicines
Antiseptics: kill bacterial/fungal pathogens
Quinine: malaria treatment
Aspirin: relieves pain/fever
Odours: frighten pests
11
...
Recognise symptoms
2
...
Cell culture: bacteria/fungi grown – appearance helps diagnose pathogen
4
...
Microscopy
6
...
Human defences
physical
mucus: sticky, traps microbes
cilia: tiny hairs pass microbes up & out (cough/sneeze)
skin

chemical
lysozymes: antiseptic – mucus/tears/saliva
White blood cells
Platelets to clot blood: help clot open wound, scabs
hydrochloric stomach acid kills bacteria

13
...
Immunisation
15
...
Antibiotics: only treat bacterial infections – inhibit cell processes in bacterium
Kills/stops bacteria’s: DNA replication / metabolism / protein production – to slow bacteria’s reproduction/growth
Prevent bacteria from making cell wall (penicillins – 1928 Fleming)
Broad spectrum: may affect useful bacteria in gut
Narrow spectrum: only affects a couple bacteria
Can’t fight virus: multiplies inside cell /different structure (no cell wall)
Too much antibiotic: bacteria becomes resistant
17
...
Core Practical: Investigate effects of antiseptics/antibiotics/plant extracts on microbial cultures
Grow bacteria in lab
Cultures grown in growth medium (solid agar jelly / nutrient brith solution) containing the
carbohydrates/minerals/proteins/vitamins they need to grow
Bacteria grown on agar plates form visible colonies on surface of jelly
Make agar plate
Hot agar jelly poured into Petri dish
When cooled/set:
inoculating loop used to transfer microorganisms to agar jelly (zig-zag motion)
Or sterile dropping pipettes & spreader used to get even covering on plate
Antibiotics: kill bacteria inside body
Antiseptics: kill bacteria outside body
Plant extracts: many plants produce antiseptics as self defence
Place soaked paper discs of different types of test substances onto agar plate with even covering of bacteria
Control disc: hasn’t been soaked – be sure that effects are down to anti-biotic only (not paper)
Leave plate for 48 hours at 25˚C
Substances should diffuse into agar jelly
Antibiotic-resistant bacteria will continue to grow
Non-resistant ones will die – shown by clear area around paper discs: inhibition zone
More efficient antibiotics: larger inhibition zone
19
...
process of developing new medicines – antibiotics
Discovery: Researchers target disease – make multiple drugs that could potentially treat it
development
preclinical testing: cells/animals
Drug tested on human cells/tissue in lab – doesn’t show full effect on body systems
Live animal testing: determines safety/effectiveness/dosage – inaccurate as animal/human physiology are different
clinical testing: human volunteers
Phase 1: Healthy males: test for harmful side effects in healthy body
Phase 2: Ill patients: see if it works & determine optimum dose (most effective / least side effects)
Placebo effect: Patients in 2 random groups
1 drug / 1 placebo – substance missing actual drug
Test if people recover by just thinking they’ve had the drug
Double-blind trial: Patients & doctor don’t know who’s who until results gathered – so all patients treated equally
Phase 3: drug tested in different countries & compared to best existing treatment
medical agency approval + production
Phase 4: long term effects/benefits analysed
21
...
monoclonal antibodies uses
pregnancy tests
Bit you wee on: has hCG antibodies with blue beads attached
Test strip: has more hormone antibodies stuck to it
If pregnant:
hormone binds with antibodies on blue beads
Urine moves up stick – carries hormones & beads
Beads/antibodies bind to antibodies on test strip
Beads get stuck on strip – turns blue
Not pregnant: urine moves up carrying beads
Nothing to stick blue beads onto test strip – doesn’t turn blue
Diagnosis
Locates blood clots
Attach radioactive element to antibody – binds to solid mesh formed by proteins in blood when there’s a blood clot
Inject & take radiation-detecting picture
Locates detectable cancers
Antibodies made slightly radioactive and carried around body through blood – bind to tumour markers in cancer cells
Take radiation-detecting picture: see location / size / if it’s spreading
treatment of cancer
Anti-cancer drug attached to monoclonal antibodies
Bind to tumour markers in cancer cells
Drug kills cancer cells – doesn’t kill healthy cells near it
advantages of use to target specific cells compared to drugs/radiotherapy
No side effects
Radiotherapy: can only be done once
Harms healthy cells near tumour
23
...
lifestyle factor effects on non-communicable diseases: local/national/global levels
obesity and malnutrition: exercise & diet
BMI =
mass kg
waist : hip calculations
(height m)2
Local
Areas of high obesity / smoking / alcohol-intake – likely to have high occurrence of certain NCD’s – pressure on resources of
local hospitals
National
NHS provides resources for patients all of UK & Sometime people with NCD’s are not allowed to work
Reduction in number of people working & excess treatment – affects economy
Global
Cardiovascular disease: no
...
cardiovascular disease treatments
life-long medication – side effects
Statin: reduces cholesterol in bloodstream
Slows rate of fatty deposits forming – reduces risks of heart attacks / strokes
Anticoagulants: make blood clots less likely
Antihypertensives: reduce blood pressure: helps prevent blood vessel damage – reduces risk of fatty deposits forming
surgical procedures
Stents: tubes inserted in arteries – keep them open to make sure blood can pass through: lowers risk of heart attack
Over time: artery can narrow – stent irritates artery and makes scar tissue grow
Patient has to take drugs to stop blood clotting in stent
Coronary bypass surgery: piece of healthy vessel taken from elsewhere & used to bypass blocked section of blood vessel
Heart transplant: doesn’t always start pumping properly & drugs need to be taken to prevent rejection
lifestyle changes
Healthy/balanced diet – low in saturated fats (increase blood cholesterol level)
Exercise
Stop smoking



---