Genpath Flashcards
What does the term pathogenesis mean?
Deals with how a disease develops
Where is smooth endoplasmic reticulum most prominent and what is its main function?
Most prominently found in the liver, adrenal cells, Leydig cells. Metabolic functions
What are the two types of secondary lysosomes?
Heterophagosomes and AUTOphagosomes
What is a heterphagasome
Formed by fusion of phagosomes and lysosomes. The phagosomes contain outside material like food particles
What are AUTOphagosomes
Very similar to hetero phagosomes in that they are formed by the fusion of phagosomes and lysosomes. However the phagosomes contain worn out and damaged cell organelles.
What are the three possible outcomes to cell injury?
Reversible injury; the cell recovers and returns to normal function
Apoptosis; Programmed cell removal and death
Cell death/necrosis
What causes reversible cell injury?
Brief hypoxia, Or brief anoxia. Or low concentrations of toxins.
What causes irreversible cell injury?
Heavy doses of toxins, sustained anoxia, and prolonged hypoxia
What happens to the nucleus of a cell when it is going through an irreversible cell injury
Pyknosis- Condensation of chromatin
Karyorrhexis- Fragmentation of the nucleus into nuclear dust
Karyolysis- Dissolution of nuclear structure as a result of enzymatic digestion
Describe the four different ways that a cell can suffer irreversible injury defined as necrosis
Coagulative, liquefactive, Caseous, enzymatic fat necrosis
What is the most common type of necrosis for a cell?
Coagulative necrosis
What causes coagulative necrosis and what is the outcome?
Anoxia. Cell membrane is preserved, organelles and nucleus coagulate
This happens to internal organs such as the heart, liver, and kidneys
What is liquefactive necrosis?
When the cell is completely digested by hydrolytic enzymes resulting in dissolution of tissues. They become soft and liquefy. This happens to brain, skin, and joints
What is caseous necrosis?
A special form of coagulative necrosis
The cost is tuberculosis; centre part of the tuberculosis granuloma becomes necrotic and the Cell falls apart. This happens in the lungs
What is enzymatic fat necrosis?
A special form of liquefactive necrosis caused by Lipo lytic enzymes and is limited to fat tissues usually around the pancreas. It happens in acute pancreatitis. Enzymes release into adjacent fat tissue degrading fat into glacier all and free fatty acids forming calcium soaps.
Fight club anyone?
What is gangrene and what is it caused by?
Dried out necrotic tissue, dark black and mummified- Dry gangrene
Bacterial infection, inflammation and secondary liquefaction- Wet gangrene
What’s the difference between physiological and pathological apoptosis?
Physiological occurs in foetal development; natural progression. For example the dissolution of webbing between the toes
Pathological occurs as a result of disease. For example, liver cells infected with hepatitis
What is fibrosis?
The extensive deposition of collagen that occurs in chronic inflammation; may cause tissue dysfunction. Example: arthrosclerosis
What’s the term used to describe the formation of new blood vessels?
Angiogenesis
Name the five groups of disease agents
Bacteria, viruses, fungi, protozoans, Helminths (Invertebrate worms)
What is Rickettsia?
Non-motile, Gram negative bacteria
What is monosomy
Loss of one chromosome leading to a chromosomal abnormality a.k.a. birth defect
What is a trisomy?
A birth defect marked by the gain of an additional chromosome
What is turner syndrome
Genetic disorder caused by the partial or complete absence of one X chromosome. Would result in a short stature, learning disabilities, heart defects, delayed puberty, and infertility.
What is klinefelters syndrome
A genetic condition that results when a boy is born with an extra copy of the X chromosome. Adversely affects testicular growth resulting in smaller than normal testicles and leading to lower production of testosterone, reduce muscle mass, reduce body and facial hair, and enlarged breast tissue.
What is the difference between an autosomal dominant disorder and an autosomal recessive disorder?
Autosomal dominant disorder’s result in a trait being fully expressed even if only one copy of the gene is present; Marfan syndrome, familial hypercholesterolaemia
Autosomal recessive disorder’s are only expressed if the gene is inherited from both parents and parents are usually asymptomatic carriers. For example, cystic fibrosis, lysosomal storage disease, phenylketonuria
What is a super bug and how did it come about? Give some examples
Super bugs are antibiotic resistant organisms resulting from antibiotic overuse. For example: MRSA, Multi drug resistant Mycobacterium tuberculosis, vancomycin resistant enterococci, Multi drug resistant pseduomonas aeruginosa, Clostridium difficile
What’s the difference between infection and intoxication?
some bacteria, all viruses, and all parasites caused an illness via infection
And intoxication results when a person eats food containing toxins that cause illness.
Does a fever indicate that a person is infectious?
No. It can be a symptom of infection as well as a symptom of non-infectious pathologies.
What is normal temperature and what constitutes as a low grade fever or a high-grade fever?
Normal: 98.6 Fahrenheit/37 Celsius
Low grade fever: up to 102 Fahrenheit/39 Celsius
High-grade fever: over 102 Fahrenheit/39°C
What are the effects of a prolonged high fever?
Can cause seizures, delirium, disorientation, and Hallucinations
What is the definition of an infection?
When an organism establishes a parasitic relationship with host
What is the process of infection?
Transmission, incubation, infection
What is required for a transmission of an infection?
A portal of entry, a mode of transportation, and a portal of exit
What’s the difference between principal and opportunistic pathogen’s?
Principal pathogens cause disease in people with intact immune systems and opportunistic pathogen’s don’t cause disease in healthy people but can cause devastating effects to people who are immuno compromised
What is another name for a hospital acquired infection?
Nosocomial infection
What is a vector?
Involving insects or animals that act as intermediaries between two or more hosts
What are the three lines of defense?
First line of defense: external barriers/secretions and microbial antagonisms
Second line of defense: inflammation
Third line of defense: immune response
What is a mycoplasma?
A very small self replicating bacteria with no cell wall that depends on the host for nutrition
How is fungi reproduce?
By budding off
What is the most common bacterial pathogen on the skin?
Staphylococcus
What is one of the most common bacterial pathogen’s of humans in general?
Streptococcus
What is Scarlett fever?
Usually follows untreated strep throat. Pyogenic exotoxin. Affects kids aged 2 to 10
What’s another name for streptococcal gangrene
Necrotizing fasciitis
What Graham negative anaerobic bacteria caused the bubonic plague?
Yersinia pestis
What does aids infect in the body?
CD m4 and T cells
What triggers a herpes outbreak?
Mucosal contact is required for the initial transmission and after the first outbreak it becomes latent in the sensory ganglia. Periodic lifetime outbreaks are triggered by a bad cold, high stress, and decreased immune function
Name the different types of herpes
Type one: cold sores
Type two: Genital
Herpetic Whitlow: herpes of the terminal phalanx (Can be type one or two)
Type three: varicella zoster ( Chickenpox/shingles)
Type for: EBV/Epstein-Barr virus/infectious mononucleosis/the kissing disease
Type five: cytomegalovirus
Type six and seven: B and T cells virus is associated with Roseola
Type eight: associated with Kaposi’s sarcoma in AIDS
What is another term for ringworm?
Tinea corporis
What is tinea versicolour
Superficial fungal infection which leads to hypo pigmented or hyper pigmented patches on the skin
What is lymphangitis
Inflammation of the lymph vessels
What is lymphadenitis
Inflammation of one or more lymph nodes
What is lymphoedema
Increase lymph fluid in the tissues
What is Lymphadenopathy
Enlargement of the lymph nodes
What are the four stages of lymphoedema
Stage zero: latent, heaviness aching and fatigue in Limb
Stage one: soft, pitting, reverses with elevation, fibrosis begins
Stage two: no pitting. No reversal with elevation. Skin changes. Chronic inflammation. Recurrent bacterial and fungal infections
Stage III: lymphostatic elephantitis
What is Stemmer sign
A thick skin fold over the second toe denoting lymphoedema
Name the four key components in the inflammation process
Changes in circulation of blood, changes in vessel wall permeability, white blood cell response, release of soluble mediators
What is the first response to injury?
Circulatory changes
What is the term pavementing mean?
Term used to describe vessel wall changes in the process of inflammation; it is when leucocytes adhere to the endothelial cells
What is transudate
Protein rich edema
What is histamine
A chemical mediator for inflammation ; Released by mast and platelets; causes increased blood vessel permeability. It is a vasodilator and a bronchoconstrictor. Last less than 30 minutes
What is Bradykinin
Plasma proteins formed by the hagemen factor. Same effects as histamine but at a slower pace. Increased blood vessel permeability. Vasodilator and bronchoconstrictor. An important difference between this and histamine is that bradykinin causes pain
What is the chemically mediated complement system?
The complement system is when several proteins are activated in cascade acting on one another. There are three pathways that activate the cascade;
classical pathway-Activated by antigen antibody complexes
Alternative pathway- Activated by bacterial endotoxins, fungi, snake venom
Lectin pathway- Activated by binding of lectin to bacteria
What are AAD’s? arachidonic acid derivatives
arachidonic acid derivatives Derived from phospholipids of the cell membrane that form Leukotrienes and Prostaglandins.
What is another name for leukocytes?
Polymorphonuclear neutrophils
What is the precursor to a mast cell?
Basophils
What are the two main phagocytic cells?
Monocytes/macrophages and neutrophils
What are possible causes of inflammation ?
Infectious, chemical, physical, immune
What type of cell holds the edges of damaged tissue together?
Myofibroblasts
What is an Angioblast?
Precursor of blood vessels; proliferate from small blood vessels at the edges of damaged tissue. Appear 2 to 3 days after injury. By DAY6 new blood vessels are formed. They allow for oxygen and nutrients to flow to the injured site and provide a route for scavenger cells to remove tissue debris and scabs
What is the role of a fibroblast?
They produce extracellular matrix. Made up of fibronectin and collagen
What are the components of granulation tissue?
Fibroblasts, angioblasts, macrophages, and myofibroblasts
What is a natural killer cell?
Large granular lymphocytes that are not T nor B lymphocytes.The function is to kill viruses, infected cells, and tumour cells. They bind to potential target cells and release cytotoxic granules and cytokinesis.
Natural killer cells burst forth from the tonsils, lymph nodes and spleen and destroy infected and cancerous cells while the immune systems T and B cells are still mobilizing.
Without natural killer cells, threatening conditions can get a strong foothold before the adaptive immune system response kicks in.