2016 1

HUBS1416 Summary Notes Abbreviations

Abbreviation Meaning

Ab Antibody

ACA Anterior cerebral artery

ACE Angiotensin converting enzyme

ACh Acetylcholine

ADME Absorption, distribution, metabolism, excretion

ADs Anti-depressants

Ag Antigen

AIDS Acquired immune deficiency syndrome

APC Antigen presenting cell

ART Antiretroviral treatment

A1 Alpha-1

A2 Alpha-2

B Both (sensory + motor)

BGL Blood glucose level

BP Blood pressure

B1 Beta-1

B2 Beta-2

B3 Beta-3

C Carbon

Ca2+ Calcium ion

CCK Cholecystokinin

Cl- Chloride ion

CNS Central nervous system

COMT Catechol-o-methyltransferase

COX Cyclooxygenase

CO2 Carbon dioxide

CSF Cerebrospinal fluid

C1 Cervical vertebrae 1

DA Dopamine

DDT Dichlorodiphenyltrichloroethane (pesticide)

DNA Deoxyribonucleic acid

g Grams

GABA gamma-Aminobutyric acid

GFR Glomerular filtration rate

GI Gastrointestinal

H/H2/H+ Hydrogen/hydrogen ion

HAI Hospital acquired infection

Hb Haemoglobin

HCl Hydrochloric acid

HIV Human immunodeficiency virus

HMG-CoA 3-hydroxy-3-methylglutaryl-coenzyme A

HPV Human papilloma virus

ICP Intracranial pressure

Ig Immunoglobulin

2016 2

Nervous System

Neuron

- Input = dendrites

- Output = axon terminals

- Integration areas = dendrites integrate many inputs to produce one response → quick

Nerve = a bundle of many neuron’s axons wrapped in connective tissue

Glial Cells - Protective, supportive and nourishing role to neurons

- Oligodendrocytes: form the myelin sheath in central neurons

- Microglia/neuroglia: macrophages of the CNS, increased number when brain tissue is infected

or damaged

- Astrocytes: regulate ionic composition of extracellular fluid (e.g. remove Na+), remove excess

neurotransmitters

Membrane Potential The potential inside a cell membrane relative to the fluid outside; it is negative under resting

conditions and becomes positive during an action potential

Neuronal Process

Creating the electrical signal All cells have a membrane potential but only nerve (excitable) and muscle cells (muscle contraction)

can rapidly change theirs to create a signal e.g. an action potential

At rest:

✓ [K+] higher inside cell (most abundant cation in intracellular fluid)

✓ [Na+] higher outside cells

✓ ∴ concentration gradients exist with the cell membrane being selectively permeable

Process:

2016 3

Peripheral Nervous System

Cranial Nerves (see pp.85-87 for flashcards) I Olfactory S Smell

II Optic S Vision

III Oculomotor M Eye movement, pupil constriction, raising eyelids

IV Trochlear M Eye movement (superior oblique – rotation of eyeball)

V Trigeminal B Sensory: Sensation of touch, pain and temperature to head, face, gums and teeth Motor: Movement of muscles of mastication

VI Abducens M Eye movement (lateral rectus – movement outward)

VII Facial B Sensory: Taste from anterior 2

3 of tongue

Motor: Movement of muscles of facial expression, secretion of tears via lacrimal glands and saliva, regulates tension on ear ossicles

VIII Auditory (Vestibulocochlear)

S Hearing (vestibular) and balance (cochlear), including posture and movement

IX Glossopharyngeal B Sensory: Taste, touch, pain and temperature from posterior 1

3

of tongue and soft tissue palate; BP, O2 and CO2 monitoring; coordination of swallowing Motor: Swallowing and parasympathetic salivary excretion

X Vagus B Sensory: Monitors BP, O2 and CO2; sensation of touch, pain and temperature in throat Motor: Stimulates voluntary muscles in swallowing, coughing and speech; stimulates smooth muscle in GI tract; stimulates secretion of digestive fluids Wandering nerve

XI Accessory M Movements of neck and shoulder muscles, voluntary swallowing and vocal cords

XII Hypoglossal M Tongue movements in speech and swallowing

Handy Mnemonics

Names of Nerves:

Oliver’s optimum occupation is tropical trigonometry – absolutely fascinating and awesome but

glosses vaguely over accidental hypoglycaemia.

2016 4

Central Nervous System

Integration in CNS The process by which the spinal cord and brain receive, process, combine and make sense of all

arriving sensory info arriving and prepare and send out an appropriate motor response

Spinal Cord – Integration of Spinal Reflexes Spinal nerves entering spinal cord

- Cervical spinal nerves exit over top of their corresponding

vertebrae, but the rest exit under theirs

Sensory and Motor Tracts Ascending: convey sensory info to brain – mostly dorsal

Descending: convey motor info to muscles/effectors – mostly

ventral + side

Spinothalamic Tract – Pain + Temp - Crosses to other side of spinal cord before ascending and

sending info to brain – OTHERS CROSS AT BRAINSTEM

- Sensory pathway from skin to thalamus

- Damage below C3 = opposite side effected

- Tract comes in dorsal side

2016 5

Pharmacology I

Terminology Drug: any substance or material that is used or intended to be used to modify/explore physiological

processes or pathological states, for the benefit of the recipient

Pharmacology: study of drug actions on biological systems

Pharmacodynamics: the biological and physiological effects of the drug; what the drug does at its

site of action

Pharmacokinetics: the absorption, distribution, metabolism and excretion of the drug (ADME); what

the body does to the drug

Naming Drugs Chemical Name: systematic name of the structure of the substance

- Useful as it tells structure of molecule

- Used by chemists

Generic Name: name of the drug itself

- Useful in identifying drugs of same class or family as they have similar endings

- Class: contains drugs which have the same action or therapeutic effect

- ADVANTAGE: Drugs can be classified into classes and effects can be predicted even if drug is

unfamiliar

Trade Name: name given by company producing drug

- Same drug may be in different formulation (eye drops, tablets, syrup)

- Active ingredient same, but colours or flavours may be added

o All with different name

- Name does not necessarily reveal what drug is

Where Drugs Act

Hormones, Neurotransmitters, Growth Factors (Endogenous Substances) - Natural: natural substance that acts upon receptor by activating/stimulating it

- Agonist: drug which acts on receptor; introduced substance that binds to receptor and produces

same effect as the natural substance would

o Example: insulin for diabetes →

o Opioid analgesics → stimulate opioid receptors

o Bronchodilators → stimulate noradrenaline (beta) receptors

- Antagonist: drug which blocks the receptor; introduced substance which binds to receptor with

no effect itself, but prevents the natural substance or an agonist from binding

o Example: beta blocker to control heart rhythm and BP → block noradrenaline (beta)

receptors

o Tamoxifen → block oestrogen receptors

o Antihistamines → block histamine receptors

Ion Channels - All major ions have own specific channels – Na+, K+, Ca2+, Cl-

- Channels open allowing ions to pass through which alter the activity of the cell

2016 6

Pharmacology II

Antimicrobial chemotherapy & anti-cancer drugs: principles of chemotherapy - Use of chemicals to destroy:

o Pathogens which have invaded the body

o Our own cells which have become malignant (cancer → selective toxicity)

- Work by exploiting a fundamental difference between the target cells and healthy cells, so that

drug is selective and only kills target and not you

o Target difference to avoid killing own cells

Bacteria (Antibacterial) - Cell wall synthesis – we don’t have a cell wall; prokaryotic organisms do

o Inhibition of cell wall synthesis (penicillin, cephalosporin, vancomycin)

- DNA/RNA synthesis – different enzymes used in human vs bacteria

o Inhibition of DNA/RNA synthesis (quinolones, rifampicin/rifampin)

- Metabolic pathways – we gain folic acid for DNA synthesis from food; bacteria make it ∴ inhibit

pathway bacteria use to synthesize folic acid (sulfa drugs) → cannot make DNA, RNA or proteins

o Inhibition of general metabolic pathway (sulphonamide, trimethoprim)

- Cell membrane – bacterium different to humans; CM easily disrupted

o Disruption of cytoplasmic membrane (polymyxins)

- Protein synthesis – different enzymes and ribosomes

o Inhibition of protein synthesis (aminoglycosides, tetracyclines, chloramphenicol,

macrolides)

Fungi (Antifungal) - Cell membrane – different to ours; humans: cholesterol is main lipid, fungi: ergosterol is main

lipid

o Inhibit ergosterol synthesis (ketoconazole, fluconazole) or bind to ergosterol and disrupt

membrane (nystatin, amphotericin)

- Cell wall – humans do not have one; fungi do

o Inhibit cell wall synthesis (caspofungin, micafungin)

Virus (Antiviral) - Is enveloped with spikes/markers for attachment and invasion

o Markers on influenza – hemagglutinin

- Inside is DNA and RNA

- ‘Viruses are rude visitors who barge inside, chuck their coat off and spreads virus’

1. Virus attaches to host cell using markers/proteins on coat → is taken into cell

o Block attachment of virus to cell (in development)

2. Virus sheds coat and releases genetic material into cell

o Block uncoating (amantadine, rimantadine [influenza A], arildone [broad spectrum])

3. Viruses genetic material directs host cell to make multiple copies of viral genetic material

o Block replication of genetic material (polymerase inhibitors, reverse transcriptase

inhibitors [herpes, HIV])

4. Virus directs host to make viral coats and assemble new viral particles

o Block assembly of new viral particles (protease inhibitors [HIV])

5. New viral particles ‘bud off’ from host cell → infect more cells

o Block budding off (neuraminidase inhibitors → oseltamivir (Tamiflu) [influenza])

2016 7

Microbiology I

Microorganisms - Live on exposed surfaces + inside us

o Most bacteria are in GI tract – up to 1000 kinds which weight 1kg

- Most are not harmful – < 5% cause disease

- Many are beneficial – aid normal biological processes (e.g. penicillin comes from mould)

History - Knowledge arose late 19th century

- Before discovery, disease was thought to be caused by air pollution

- Study was possible after 1673 when Anton van Leeuwenhoek created the first microscope

- Importance of hand washing discovered

- Louis Pasteur proved existence of microorganisms

o Dispelled spontaneous generation theory

o Led to process known as pasteurisation – heating fluids to 56°C for 30 mins to avoid them

spoiling, used for milk

Relationships - Mutualism: mutually advantageous (e.g. bacteria in colon)

- Commensalism: close relationship and do no harm (e.g. streptococcus in nose)

- Parasitism: live on or in another organisms and cause pathogenic conditions (e.g. tapeworm)

Scale & Classification of Microorganisms

procaryotic

eucaryotic

Bottom of the ocean –

hydrothermal vents

2016 8

Microbiology II

Infection Control: Background - Doctors used to wear thick, waxed coats, hats, masks with a long beak and carried a cane which

were all old methods of disease prevention, whether they knew it or not

- Microorganisms (MOs) play key role in our body’s, agriculture, food production and recycling

o Responsible for food spoilage, water contamination and disease

- Control of MOs = essential for health

Traditional Methods - Food preservation - as food was seasonal

o Drying and curing (meats)

o Salt or sugar added → reduce water content → increase osmotic pressure (ineffective for

fungi)

o Vinegar → reduce pH → pickling

o Food heated and sealed in containers

- Created conditions where MOs could not thrive

o Bactericidal – killing

o Bacteriostatic – stop/slow growth

- Bodies and clothing of dead burned + burning scented plants

- Semmelweis (1947): introduced hand washing w/ chlorinated lime due to increased mortality in

women giving birth who had been handled by those also performing autopsies

o Reduced mortality rate or puerperal fever from 35% to 1%

o Theory rejected

o Gained acceptance after Louis Pasteur

- Lister (1865): introduced cleaning of surgical instruments and wounds w/carbolic acid

o Reduced cases of fatal post-op gangrene infections

o Carbolic acid was caustic (burned) although was an effective disinfectant

Rate of Death - Biocidal agents must come into contact with each

microbe to kill them

o Takes time

- Pattern is exponential – killing curve

o 90% killed in 1st minute

o 90% of those left killed in 2nd minute, etc.

- Altering factors:

o Type of MO

o Size of population

o Growth phase – exponential; multiply while being

killed, stationary; stopped due to lack of nutrients

o Concentration of antimicrobial agent – up to threshold, if too much, no effect

▪ Provides sufficient molecules of chemical to interact with MO

▪ Weaker of stronger solution and insufficient time will compromise process

▪ 70% ethanol more effective than 95% - due to [water], 70% evaporates slower and

creates osmotic pressure

o Duration of exposure – heat and chemical

o Local environment – pH, presence of organic matter

2016 9

Immunology I

Immune System: Background - MOs predate animal life

- To survive, animals developed ways to protect themselves from harmful effects of MOs

- Humans have over 100 trillion bacteria in gut of 40000 different species

o Most cause no harm

o Importance to our health

o Changes in normal MO flora = disorder

- Some MOs cause pathogenesis

o Example: extracellular – bacteria, parasites (worms), fungi; intracellular – bacteria,

parasites, viruses

- Our immune system recognises foreign or abnormal cells and removes them from body

Innate Immunity - Non-specific

- Present at birth

- General in action – similar mechanisms against wide range of pathogens

- 1st and 2nd lines of defence

Lymphatic System - Key components:

o Lymphatic vessels – one-way system, unlike blood vessels

o Lymph – fluid carried in vessels

o Lymph nodes – house T cells which attack antigens + trigger B cells, macrophages

- Includes spleen, thymus, tonsils, other lymphoid tissue

- Process: In capillary beds in circulatory system, exchange of nutrients + removal of waste →

from arteriole, interstitial fluid to venous end → only 17L taken up by venous end → 3L becomes

lymph, taken up by lymph vessels via hydrostatic pressure → filtered through lymph nodes →

returned via lymphatic ducts which drain to jugular vein (upper right) from right lymph duct and

subclavian vein (rest) from thoracic duct

- Returns the 3L to maintain homeostasis + BP

Lymph Nodes - Approx. 600

- Large groups around in cervical, axillary, inguinal

(groin) regions

- Immune function:

o Phagocytes (macrophages): destroy foreign

cells

o Lymphocytes: activate adaptive immune

system

2016 10

Immunology II

Immunisation: Background - 8000 generations of modern human in 250000 years

- 8000 generations of E. coli in 100 days

- Evolution requires selection and mutation – evolution of pathogens to evade and combat our

immune system

Immunisation

Passive - Production of Abs in one individual and transferred to another individual

- Natural (mother – IgG, IgA) or artificial (gamma globulin injection – anti-venom, anti-Hep A)

- Immediate and asymptomatic but temporary

- Suitable for immunocompromised

- Expensive

- Risk of accidental infection

- May result in serum sickness

Active - Production of Abs by individual following exposure to antigen

- Natural (exposure) or artificial (via vaccine with dead or attenuated pathogen)

- Takes time to develop but memory created – long lasting

Vaccination: History - 1000BC – smallpox survivors became immune

- 900AD – inoculation/variolation against smallpox common in India and China

o Powdered scab from mildly infected person injected into arm subcutaneously

o 1718AD – brought to England by Lady Mary Wortley Montagu

▪ Survival rate for variolated- 90-95%

▪ Survival rate for un-variolated – 40-80%

▪ 20% survivor had disfiguring scars

▪ 5% died and variolation was outlawed - CONTROVERSIAL

- 1796 – Edward Jenner noticed milk maids with cowpox did not get smallpox

o Inoculated James Phipps (8-year-old) with pus from cowpox

o Phipps was protected against smallpox infection

- 1798 – first smallpox vaccine developed

- Louis Pasteur developed vaccines for Cholera, Rabies and Anthrax

Vaccination: based on infection with ‘weakened or dead’ pathogens to illicit immune response; is a

type of immunisation but is not guaranteed

Inoculation: infection with live pathogens in a controlled manner

Good Vaccine - Stimulates humoral and/or cell-mediated immunity

- Generates immunological memory

- No harmful side effects + no exposure to infection – use of modified pathogen

- Has stability/shelf life – cost effective

- Easily administered – kids hate needles ∴ tablets, syrup

2016 11

Genetics I

Genetics: History - Science that looks at genes and how they dictate:

o Development

o Structure

o Behaviour

- Gregor Mendel

o 19th century monk

o Cultivated pea plants to study physical traits (colour, plant height, flower position)

o Discovered patterns in offspring occurred in ratios

▪ Some traits skipped a generation and reappeared in next – recessive

o Example: plant height

▪ Self-fertilising short plants resulted only in short plants

▪ Crossing tall and short plants produced only tall plants

▪ Allowing these plants to fertilise each other produced tall and short in 3:1 ratio

- Mendel’s Conclusions

o Genes occur in pairs – allows short to arise from tall

o Ratios suggest information was distributed to offspring equally with one characteristic being

dominant over the other

o 2 laws proposed: segregation + independent assortment

- William Bateson: biologist → ‘genetics’ + promoted Mendel’s work

- New biological science

- Studied structure and function dependent on genes

- Concept of inherited traits

- Variation of organisms

Genome Collection of all genes in specific organism

Allele Alternative forms of a gene located on homologous chromosomes

Genotype Specific alleles that make up a person’s genotype; responsible for phenotype

Phenotype Physical characteristic of gene expression dictated by genotype; is observable

Recombination Rearrangement of genetic material by crossing over of chromosomes

Biology of Genetics - 75 trillion somatic cells

- 46 chromosomes in 23 pairs in NUCLEUS

o 1-22

o 23: sex chromosomes

- One pair from mum, one pair from dad

- Sperm + ova are haploid → 23 chromosomes

DNA Structure - Watson & Crick 1953: discovered structure of DNA – two chains of nucleotides w/ sugar-

phosphate backbone

2016 12

Genetics II

Inheritance Patterns: Background - Inheritance acknowledged for 1000+ years

- Basis of selective breeding – mixing DNA from organisms with desired characteristics

o Milk yield – 3000L → 10000L

o Egg yield – 70/year → 250/year

o Meat yield

o Grain yield

- Trait: measurable/observable feature (phenotype) influenced by genetics (genotype) and

sometime the environment; can be multifactorial, that is, due to multiple genes

o Hair colour, eye colour, height

- Epigenetics: study of changes by modification of gene expression rather than the genetic code

itself

- Units of inheritance = genes → alleles dictate phenotype

Alleles - See Genetics I (p. 79)

- Diploid cell: 2 of each chromosome ∴ 2 of each gene

- Have 2 alleles of each gene – one from Mum, one from Dad

o More than 2 possible alleles for any gene – code for variant proteins

o Blood type: ABO

Dominant & Recessive Concepts - Homozygous gene pairs – 1 option for protein function and display corresponding trait

- Heterozygous gene pairs – display dominant trait as recessive is overridden

o Must have homozygous recessive to display recessive trait

- Dominant: dominant allele (capital letter) is present either homozygous AA or heterozygous Aa

- Recessive: only occurs when homozygous alleles are present – aa

Punnett Squares - Each gene = 2 alleles

o Not with sex chromosomes

- If genotypes of parents are known, we can predict probability of offspring’s genotype

2016 13

Olfactory (I)

Smell

Optic (II)

Vision

Oculomotor (III)

Eye movement,

raising eyelids, pupil

constriction

Trochlear (IV)

Superior oblique

(rotation) eye

movement

Trigeminal (V)

S: sensation in face

M: chewing