Sem 1 Flashcards
Sodium reabsorption along the length of the nephron is key to renal function what are the key mechanisms and principles for sodium reabsorption from the filtrate into the renal interstitial space
Early in the nephron cotransporters move Na+ across the apical membrane eg the Na+/H+ exchanger in the proximal tubule
In the distal nephron Na+ passes through the membrane by itself (through ENaC)
Throughout the nephron basolateral Na/K ATPases move Na+ from the intracellular side to the interstitial space
3HCO3-/Na+ cotransport the electrochemical gradient of 3HCO3- that drives this cotransporter
Countercurrent multiplier maintaining Na+ gradient for reabsorption
NCCK2 transporter in the thick ascending limb as a key transporter
Na+ movement necessary to create an osmotic gradient that then allows water movement
Na+ movement is under hormonal control: renin-angiotensin-aldosterone system
Describe the role of the neutrophil in pathogen control
Neutrophils are white blood cells that play an important role in the innate immune response
Neutrophil circulate around the body in the blood stream and an infection is present they are attracted to site of infection by chemokines (chemotaxis) and migrate across the endothelium to the site of infection
Neutrophils recognise pathogens using pattern recognition receptors which recognise PAMPS/DAMPS
Neutrophils are able to phagocytose pathogens
Phagosomes then fuse with lysosomes to enable pathogen killing
Lysosomes contain toxic granules (proteases, proteinases, oxygen free radicals) that kill and digest the pathogen
Neutrophils are able to extend neutrophil nets to capture pathogens from outside the cell
Absence of neutrophils results in an inability to control extracellular bacteria and fungi
Why would you measure the neutrophil count in a patient
Neutrophilia- too high suggests infective process, any cause of inflammation that triggers innate response
Neutropenia- too low diagnose immunodeficiency- primary immune defect or secondary to chemotherapy
Identify risk of extracellular infection and fungi- can implement prophylactic treatment
May be benign ethnic neutropenia
Outline the main tenets of the social model of disability include one criticism and describe people themselves see the model
The social model of disability is the most current model for disabled people and disability movements and organisations working with disabled people. The social model of disability sees disability as a consequence of environmental, social and attitudinal barriers, the definition by disabled peoples international for the term disability is “ the loss or limitation of opportunities to take part in the normal life of the community on an equal level with others due to physical and social barriers” its main argument is that disability results when society fails to adjust to meet the needs and aspirations of a disabled minority. One of the criticisms of this model is that it implies that all disability will be eliminated if society removed all the barriers and the challenge is that some people would still be disabled even if all the barriers were removed as aspects such as a persons own capabilities and dealing with aspects of disease such as pain is not considered. It is important to understand that the social model of disability is seen as an empowering model owned by disabled people themselves and is very popular with disabled people and disability organisations
Under the equality act 2010 there are 9 protected characteristics what are they
Age
Disability
Gender reassignment
Marriage and civil partnership
Pregnancy and maternity
Race
Religion or belief
Sex
Sexual orientation
How does the Na+ concentration in Bowman’s space compare with that in the glomerular capillaries and why
Same, free filtration
How does the Na+ flux (or flow, measured for example in mol/min) in the renal efferent arteriole compare with that at the start of the proximal tubule and why
Higher in renal efferent arteriole as the concentrations are similar but the flow rate is much higher in the renal efferent arteriole (RBF-GFR)>GFR
How does the Na+ concentration inside the late part of the thick ascending limb compare with that in the adjacent interstitial space and why
Lower inside the TAL due to active removal of sodium by the NKCC2 Co transporter
Name one diuretic that acts by decreasing the reabsorption of sodium in the kidney, describe its mechanism of action and one side effect
Furosemide inhibits NKCC reducing sodium accumulation in the renal medulla hence decreasing the drive for water reabsorption in the descending limb and collecting ducts. Cause hypokalaemia secondary to increased sodium delivery to collecting ducts leading to K+ loss in the urine
Cardiovascular response to exercise and the factors that determine systolic and diastolic pressure, explain the changes in the students systolic (high), diastolic (low) and mean arterial blood pressure immediately after exercise 150/60
Systolic pressure determined by elasticity of aorta and stroke volume. Exercise has no effect on the elasticity of aorta but increases SV (due to requirement for an increased CO during and immediately after exercise) therefore the increase in SP reflects the increase in SV from resting level. DP determined by afterload/total peripheral resistance and heart rate. Diastolic pressure has decreased reflects the large fall in TPR seen in whole body exercise due to vasodilation of skeletal muscle. Even though heart rate has increased the fall in TPR predominated and DP fallen. Mean arterial blood pressure (calculate both at rest and exercise) no significant difference
Briefly describe two of the main benefits of exercise/exercise training to the cardiovascular system in cardiovascular rehabilitation
Change in autonomic balance (decreased sympathetic activity increased parasympathetic activity)- altered autonomic activity features of coronary artery disease, hypertension, atherosclerosis
Enhance blood vessel dilator function (decreased reactive oxygen species, increased vasodilator nitric oxide)- endothelial dysfunction features of coronary artery disease, hypertension, atherosclerosis
Changes to heart including eccentric hypertrophy and increased inotropy
Name 4 key immune cells or cytokines that are important for control of M.tuberculosis
CD4 Th1 cells
Macrophages
Dendritic cells
IL12 and IFNg and TNFB
What is a granuloma and why do they form following a primary TB infection
A granuloma is a complex interaction between immune cells and stroma
A central core of macrophages and giant cells, epitheloid cells and histiocytes surrounded by T cells and connective tissue
Formed when macrophages are unable to eliminate intracellular MTB infection, granuloma isolates infection and prevents dissemination
Give three acquired risk factors for the development of symptomatic pulmonary M.tuberculosis infection
Anti TNFa treatment
HIV-1 infection
Malnutrition/low body weight
Silicosis
Overcrowding
Diabetes
Haematological malignancy
Bone marrow transplantation
Anticytokine antibodies
Patient with M.tuberculosis is not regularly picking up prescriptions what are the wider public health implications of this mans behaviour
Spreading TB if still active
TB antibiotic resistance
