Notes of a High Distinction Student: Bachelor of Biomedical Science

Many of the different professional groups may be involved in dealing with toxic chemicals including chemists, environmental scientists, food scientists, forensic scientists, clinical scientists, and regulators. Depending on their professional roles, they may take different approaches to dealing with toxic chemicals and their effects.  5 Types of Toxicology Specialty Fields Descriptive toxicology Involves toxicity testing of drugs and chemicals. Decides if a substance is toxic and the level of toxicity. Mechanistic toxicology Involves how toxic chemicals cause toxicity effects at the biochemical and system level e.g. neurochemical site blockage Regulatory toxicology Assessment of therapeutic and consumer chemicals by regulatory bodies. Various federal government agencies set standards for use, transport, and storage.  Clinical toxicology Clinical Toxicologists ask the question, what was the victim poisoned with? Their conduct is in support of medical investigations

Objectives Appreciate that all substances are potentially toxic Have a basic understanding of the scope of toxicology Appreciate that many scientists, technicians, clinicians, and regulators are concerned with toxic chemicals Understand there are different fields and applications of toxicology and different aims and approaches when dealing with toxic chemicals and effects The scope of toxicology Toxicology is the study of the harmful effects of chemicals on living organisms. Toxicology is a branch of pharmacology, dealing with the origin, nature, chemistry and adverse effects of chemical substances.  Toxicology is the study of harmful effects of chemicals on living organisms, including the origin, nature, chemistry & adverse effects of chemical substances Potentially toxic substances include: Food Drinking water Air Medications Cosmetics Bites and Stings Venomous animals and plants   Today, much knowledge of toxic substances comes from lab-based experiments

The Intrinsic and Extrinsic Clot Pathway When damage occurs to tissues, or there is damage to a nerve, a number of vascular responses occur.  Neutrophils are attracted to the injured site which stimulates the release of histamine, basophils, platelets, mast cells, and kinins.  Prostaglandins and lipids are released from the damaged cells. Vasodilation and increased permeability of blood vessels cause heat, redness, and swelling. Pain occurs from damage to the nerves, as well as toxic chemicals which are released from microbes. Kinins can irritate nerve endings while prostaglandins intensify and prolong the pain. Increased blood flow to tissues causes blood clotting factors which leak into the tissues which set the clotting sequence in motion. Fibrinogen in the blood converts to fibrin making a meshing over the damaged site to trap the microbes and stop the spread of infection.

Assignment title: Is it Bird Flu or Human Flu Subject: Medical Microbiology and Immunology Mark:  8/10 lost two points for needing more specific information and missing the websites on the reference list. Criteria Identify the pathogen(s) involved.  Outline the type of immune defenses that might be operating. How does the pathogen enter the body, cause disease and how is it transmitted? What is the outcome of the infection? How is the disease diagnosed? What strategies exist (if any) to control the infection? References Is it Bird Flu or Human Flu? The Enemy - Microbes Avian Influenza A, also known as H5N1 or Bird Flu, is an enzootic member of the orthomyxoviridae family, representing an enveloped, ssRNA viral molecule, with surface hemagglutinin and neuraminidase surface glycoproteins. (1) The Defence - Host Disease H5N1 is more prevalent in birds in China, Asia, Europe and Africa, however, mutations have crossed the animal to human barrier causing destruc

Progressive Types Of Cell Injury & Response Investigating disease includes collating a clinical history, examination, offering a provisional diagnosis and providing a confirmation of diagnosis via diagnostic or lab investigation. Cell injury can be caused by: Physical trauma Extreme temperatures  Electrical disturbance   Chemical or radiation poisoning  Biological agents Nutritional issues Most of the above cause radical production, a decrease in oxygen delivery or an increase in calcium intercellular release. They could be either reversible or irreversible causing necrosis (cell/ tissue injury) or apoptosis (normal physiological process). Hypoxia conditions can include: Stroke Brain trauma Arteriosclerosis  Injury leading to hypoxia A decrease in ATP production  An increase in sodium and H2O into cells An increase in potassium outside the cell Increased osmotic pressure Vacuoles formed Increased vaculation Increased hydropic degradation 

Sequence Of Events for Vascular Cellular Repair and the Inflammation Response A break in the skin occurs Bacterial reproduction increases Macrophages engulf bacteria Macrophages secrete cytokines Activated mast cells secrete histamine Histamine and cytokines increase dilation of blood vessels White blood cells (WBCs) adhere to capillary lining (pavementing) WBCs migrate to injured site via endothelial cellular gaps via diapedis movement Monocytes turn into macrophages Macrophages and neutrophils engulf pathogens (phagocytosis) Red Blood Cells increase in concentration causing redness and head An increased amount of fluid migrates to the area causing swelling and pain. Tissue repair commences and systemic responses may be evident e.g. fever What is involved in the tissue repair response? Resolution – the toxin is neutralized, oedema decreases, capillary permeability decreases and vasoconstriction occurs Regeneration & replacement – proliferation