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Endocrine Disorders
Diabetes mellitus, thyroid disease, etc.
38
Medical
Graduate
04/08/2010

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Cards

Term
The leading cause of end-stage renal disease, amputation of the lower extremities (non-trauma) and adult-onset blindness in the US
Definition
Diabetes mellitus
Term
Diabetes mellitus has a wide variety of underlying causes, list the broad classes
Definition
Type 1, Drug-induced, Gestational, genetic conditions assocaited with DMII (Down Syndrome, Kleinfelter, Turner), Genetic defects of B-cell function, Genetic defects in insulin action, exocrine pancreatic disease (pancreatitis, neoplasia), Endocrinopathies (acromegaly, hyperthyroidism), Infections (Coxsackie B, CMV, Congenital rubella), type 2 diabetes mellitus (insulin-resistance and insulin dysfunction)
Term
True or false: low levels of circulating insulin and high levels of circulating glucagon stimulate glycogen synthesis and suppress glycogenolysis and gluconeogenesis
Definition
False, glucagon stimulates hepatocytes to break down glycogen (glycogenolysis) and make more glucose (gluconeogenesis) to prevent hypoglycemia
Term
This biomolecule, produced from the conversion of pre-proinsulin in the golgi appartus, is secreted in equimolar concentrations with insulin from B-cells in the pancreas, making it a useful marker for B-cell function
Definition
C-peptide, produced from proteolytic cleavage of pre-proinsulin in the golgi appartus of B-cells in the pancreatic islet cells
Term
True or false: the most important stimulus of insulin production and secretion is glucose
Definition
True
Term
This transporter on B-cell membranes takes glucose into the pancreatic B-cells independent of insulin
Definition
GLUT-2
Term
True or false: ATP generated from glucose in B-cells activates potassium channels that increase membrane potential to release glucose
Definition
False, ATP inhibits the inward-rectifying K channel, which increases membrane depolarization, causing an influx of Ca-ions which triggers glucose secretion from the cell
Term
This compound is complexed to the inward rectifying K-channel on B-cells, also a target for some pharmacologic agents used in the tx of DMII
Definition
Sulfonylurea
Term
These two cells make up the majority of cells involved in insulin-mediated glucose uptake
Definition
Skeletal muscle cells and adipocytes
Term
True or false: Glucose taken up by adipocytes is stored as a lipid, and inhibits lipid degradation
Definition
True, which sucks
Term
True or false: In addition to glucose transport and anabolic stimulation, insulin has mitogenic properties in some tissues
Definition
True
Term
Through phosphorylation of the tyrosine kinase portion of the B-subunit of the insulin receptor, proceeding through the PI-3K and MAP kinase pathways, Insulin triggers the expression and insertion of this transporter in the cell membrane
Definition
GLUT-4, the insulin-dependent glucose transporter
Term
These genes, also linked with Hashimoto's thyroiditis, are implicated in susceptibility to DMI
Definition
CTLA4 and PTPN22
Term
True or false: The two metabolic defects that characterize DMII are a decreased response of peripheral tissues to insulin (insulin resistance) and B-cell dysfunction leading to inadequate insulin secretion compounding hyperglycemia and insulin resistance
Definition
true
Term
This event in the pathogenesis of DM II is likely to be the largest contributor
Definition
Loss of insulin sensitivity in hepatocytes, leading to increased gluconeogenesis and glycogenolysis
Term
True or false: Obesity often results in insulin resistance with or without hyperglycemia
Definition
True, ie part of the metabolic syndrome
Term
True or false: Central adiposity is a bigger contributor to insulin resistance than peripheral adiposity
Definition
True
Term
These four factors contribute to increased DMII risk in obese individuals
Definition
Elevated non-esterified fatty acids in liver and skeletal muscle cells, adipokines (lectin) that affect fatty acid metabolism throughout the body, inflammation from pro-inflammatory cytokines (TNFa, IL2, IL6) secreted by adipose tissue, and peroxisome proliferation-activated receptor gamma (PPARy) an important transcription factor in adipose tissue that promotes secretion of anti-hyperglycemic adipokines (lectin, adiponectin) and the target of the anti-DM2 meds thiazolidinediones, which are PPARy agonists
Term
The key mediator in pathogenesis of type 2 diabetes mellitus.
Definition
glucotoxiciy from chronic hyperglycemia
Term
The four pathophysiologic consequences of advanced glycation end-products are:
Definition
AGE bound to RAGE on macrophages causing inflammatory cytokine release, especially in the intima of blood vessels, generation of ROS in endothelial cells, increased procoagulant activity on endothelial cells and macrophages, and enhanced proliferation of vascular smooth muscle
Term
True or false: de novo synthesis of diacyl glycerol in response to intracellular hyper glycemia results in increased nitric oxide synthesis and decreased endothelin-1 synthesis
Definition
False, nitric oxide, a vasodilator, is lowered by decreased expression of the nitric oxide synthase enzyme. Endothelin-1 is increased
Term
Increased production of profibrogenic factors, TGF-B for instance, from increased intracellular glucose concentrations is a result of increased activation of this enzyme
Definition
protein kinase C
Term
True or false: Nerve tissue is damaged by hyperglycemia in spite of lacking insulin-dependent glucose transport systems
Definition
True, chronic hyperglycemia increases intracellular glucose concentration, which is reduced to fructose by aldose reductase and NADPH, which reduces the amount of NADP+ available for antioxidant synthesis (glutathione), increaseing oxidative stress in the cell
Term
List the three types of endogenous Cushing's syndrome
Definition
an ACTH secreting tumor/hyperplastic mass in the pituitary, hypersecretion of cortisol by an adrenal adenoma, carcinoma or hyperplastic gland, and secretion of ectopic ACTH by a nonendocrine neoplasm
Term
T or F: Primary hypersecretion of ACTH accounts for 10-20% of cases of endogenous hypercortisolism
Definition
False, 70-80%, remainder come from nonendocrine neoplasms or adrenal hypersecretion
Term
T or F: Cushing's disease affects men about five times more frequently than women.
Definition
False
Term
What can be said of serum ACTH levels in the case of Cushing's disease due to an adrenal neoplasm versus a pituitary neoplasm?
Definition
In adrenal neoplasms the serum ACTH is low due to inhibition from elevated cortisol, wherein pituitary neoplasm the ACTH is high as well as the cortisol since the tumor is secreting ACTH
Term
Which ectopic ACTH-secreting tumor is usually responsible for Cushing's disease
Definition
small cell carcinoma of the lung
Term
The most common alteration of pituitary tissue in Cushing's syndrome, resulting in replacement of granular basophilic cyoplasm of ACTH cells with a homogenous lightly basophilic material due to keratin filament accumulation, is called ()
Definition
Crooke hyaline change
Term
Describe the dexamethasone suppression tests
Definition
Low dose should inhibit ACTH secretion if there is NO pituitary abnormality at all, points to either an exogenous Cushing's syndrome (drugs usually) or not Cushing's at all, High dose rules out pituitary tumor vs. ectopic source of ACTH since ectopic sources are less sensitive to neg. feedback than pituitary tumors
Term
Which enzyme deficiency accounts for more than 90% of CAH?
Definition
21 hydroxylase or CYP21B deficiency, results from pseudogene (CYP21A) replacement of functional gene
Term
When massive adrenal hemorrhage complicates a bacteremic infection it is called ()
Definition
Waterhouse-Friderichsen syndrome
Term
What 3 classifications exist for adrenal insufficiency?
Definition
Primary acute insufficiency or adrenal crisis, primary chronic adrenocortical insufficiency (Addison disease) and secondary adrenocortical insufficiency
Term
What organisms are usually implicated in the Waterhouse-Friderichsen syndrome?
Definition
Neisseria meningitidis, pneumcocci, pseudomonas, HiB, and staphylococci
Term
90% of primary adrenal insufficiency are caused by what 4 conditions?
Definition
Autoimmune adrenalitis, TB, AIDS, and metastatic cancers
Term
List some signs and symptoms of adrenal insufficiency
Definition
Easy fatigability and weakness, GI disturbances, hyperpigmentation in sun exposed areas and pressure points, hyperkalemia hyponatremia volume depletion and hypotension
Term
T or F: In secondary adrenal insufficiency, hyperpigmentation is lacking b/c melanotropic hormone levels are low
Definition
True
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