Sem 2 Flashcards
By what collective term are spinal motor fibres that originate in the cerebral motor cortex and decussate at the spinal levels of their target lower motor neurones known
Ventral corticospinal tract
Name the type of glial cells that form the epithelium that lines the ventricular system of the brain and spinal cord
Ependymal cells
47 year old male no previous medical history presents to GP complaining of episodic headaches, sweating, heart palpitations and tremor over past 2 years. Investigations raised plasma catecholamines both adrenal glands are excluded of primary cause disorder what’s most likely diagnosis
Paraganglioma
Polycystic ovary syndrome presents with 3 typifying features namely irregular periods or anovulation, enlarged ovaries containing many fluid filled sacs or follicles that surround the ova and third feature- what is it
Excess levels of androgens
Metastatic spread of cancer cells is thought to result from structural failures of tissues in which the cancer originates primarily. Name the collective apparatus that maintains integrity and normal local functions within the tissues
Extracellular matrix
Typical epithelial cell contains several major classes of cell-cell junctions, namely; adherins junctions, tight junctions, desmosomes and gap junctions. Adherens junctions and tight junctions are known to play essential roles in maintaining the epithelial program
Apart from regulating substances that pass between epithelial cells, name another epithelial function underpinned by tight junctions
Maintenance of cell polarity
Patient undergoes CT scan of the abdomen for unspecific lower pain which reveals 6cm mass in left adrenal gland
A. What are the two most important problems to look for when investigating a patient with adrenal tumour
B. What conditions need to be excluded and which tests would you employ to do this
A- exclusion of hormone excess and malignancy
B- patient should undergo: exclusion of Cushing’s by Dexamethasone overnight suppression test and/or 24hr urinary free cortisol. Exclusion of phaeochromocytoma by 24hr urinary catecholamines (or metanephrines or plasma metanephrines). Exclusion of primary hyperaldosteronism in particular in patients with hypokalaemia and/or hypertension by measurement if the plasma renin activity/serum aldosterone ratio
A. Identify a protein complex and its component molecules in the photoreceptors that is responsible for detecting and responding to light
B. What ion channel is affected by the biochemical signalling process initiated by light and what are the electrical and functional consequences for the cell
C. Identify neuronal cells in the direct pathway connecting the photoreceptors to the optic nerve. How can they be classified. What is the electrical response of each cell subtype to signals generated by light arriving via the direct pathway. What is the influence of the indirect pathway on their electrical activity
A- rhodopsin; retinal and opsin
B- cGMP-gated cation channel- closed by reduced levels of cGMP (metabolised by PDE). Na influx stops. Cell hyperpolarises. Decreased glutamate release onto bipolar cells
C-bipolar cells which synapse with ganglion cells. ‘On’ and ‘off’. On-depolarised by light via direct pathway (hyperpolarised via indirect pathway) opposite for ‘off’ cells
What are 5 commonly accepted reasons you may feel an individual is deserving of moral status
Human- humans care for their own species and therefore afford them moral status
Autonomous- if an individual is able to make their own decisions this makes them matter enough to have moral status
Sentience- if an individual is able to experience pleasure or pain they are deserving of moral status
Personhood/sapience- if an individual can maintain continuous mental state (such as rational thought, or hopes and dreams for the future) they are deserving of moral status
Potentiality- if an individual does not yet have one of the above qualities but could in the future they are deserving or moral status
Patient- if an individual is under our care in the role as healthcare providers they are deserving of mortal status
A. What are the main extrinsic factors known to contribute to the incidence of cancer in UK. Give examples of the suggested mechanisms leading from carcinogen to cellular transformation
B. What are the factors measured in risk assessment of carcinogen
A) the data for 2010 indicates that the main contributors for increased risk of cancer are tobacco, diet, obesity, alcohol, occupational hazards and UV radiation with tobacco and diet being the two big hitters, 19.4% and 9.2% increased incidence respectively
Carcinogens contained in tobacco or food components (eg in processed meat) can be metabolically activated in cells of a human body and react with DNA or proteins forming covalently bound products known as DNA adducts or protein adducts which interfere with normal functions of the cellular molecules. If the adducts persist during DNA replication, miscoding can occur, which leads to a permanent mutation in DNA sequence
Obesity is a cause of low-grade inflammation and the release of inflammatory cytokines promoting cancer. It can also lead to type II diabetes and insulin signalling which can fuel cancer. Obesity leads to dysregulation of adipokines which collectively stimulate tumour growth.
Chronic alcohol consumption leads to accumulation of acetaldehyde which is a mild mutagen and carcinogen damaging DNA
B) risk assessment involves three factors: 1. Potency- the potential for a given amount of a substance to cause cancer. 2. Type of exposure- whether the exposure is one time (acute) or long term (chronic) and whether it is unavoidable (eg in the workplace or in the air we breathe). 3. Dose response: a dose-response trend describes what happens to cancer risk as the level of exposure increases or decreases
