(M) Lec 2: Carbohydrates (Part 2) Flashcards
Presence of Insulin and its Receptors
Once glucose enters the cell, it will undergo what pathway/s to be converted into pyruvate along with lactate and ATP?
EMP or glycolysis
Presence of Insulin and its Receptors
Pyruvate will enter what pathway to produce more ATP along with CO2 and H2O indicating that higher ATP is offered to the cells?
Tricarboxylic Acid Cycle
Absence of Insulin and its Receptors
If glucose cannot enter the cells, energy will be sourced from where through the process of gluconeogenesis?
Clue: 2 answers
Fats and Proteins
Absence of Insulin and its Receptors
What will also be produced along with glucose once energy is sourced from fats and proteins?
Clue: 2 answers
Ketone bodies and Urea
Absence of Insulin and its Receptors
Increased ketones will result to what?
Ketoacidosis
Any degree of glucose intolerance with an onset or first recognition during pregnancy caused by a deficiency of insulin, metabolic, and hormonal changes
Gestational DM
The screening test for gestational DM is performed between 24-28 weeks of pregnancy through what test?
Glucose Tolerance Test
TOF: Pregnant women who are diabetic are counted as cases of Gestational DM
False (it is only counted as GDM when the diabetes is brought about by the pregnancy)
How many Gestational DM cases may lead to DM? (in percent)
30-40%
Refers to when FBS concentrations are between normal and diabetic values (quantitated at 100-125 mg/dL)
Impaired Fasting Glucose
What is the normal glucose level range when anything above 100 mg/dL is considered diabetic?
70-100 mg/dL
Refers to when blood glucose concentrations are less than those required for diagnosis of DM (the Oral Glucose Tolerance Test results are between normal and diabetic values)
Impaired Glucose Tolerance
Glucose Measurement
What is the best specimen choice for glucose measurement?
Serum
Glucose Measurement
Whole blood results are how many percent lower (compared to serum) since cells use glucose as a source of energy?
11%
Glucose Measurement
CSF glucose is approximately how many percent of plasma concentrations?
60%
Glucose Measurement
The liquid portion of blood must be separated within how many hours and put in a gray tube containing fluoride?
1 hour
Glucose Measurement
A gray top tube is aka as what? (it prevents a false-decrease in glucose since cells use it as a source of energy in cases of high WBC count)
Antiglycolytic agent
Glucose Measurement
Fasting should be done for how many hours not succeeding how long?
Note: Provide 2 answers in hours
Standard: 8-10 hours
Not more than: 16 hours
Also recommended to last for 6-8 hours
Glucose Measurement
Glucose decreases by how many percent per hour at room temperature (20-25ºC) in uncentrifuged blood?
5-7%
Glucose Measurement
Glucose is metabolized at refrigerated temperatures (4ºC) at about how many mg/dL per hour?
1-2 mg/dL
Glucose Measurement
What cells metabolize glucose in clotted and uncentrifuged blood resulting in false decreased values?
Clue: 2 answers
RBCs and WBCs
Oxidation-Reduction Methods
Principle: Cupric ions are converted to cuprous ions in an alkaline solution through the action of glucose
Alkaline Copper Reduction
Oxidation-Reduction Methods
In Alkaline Copper Reduction, what is the basis of the color change?
Amount of glucose
Oxidation-Reduction Methods
This type of Alkaline Copper Reduction Test is a modification of the Folin-Wu method which uses citrate and tartrate with a stabilizing agent
Benedict’s
Oxidation-Reduction Methods
This type of Alkaline Copper Reduction Test uses alkaline copper tartrate
Fehling’s
Oxidation-Reduction Methods
This type of Alkaline Copper Reduction Test uses phosphomolybdate
Folin-Wu
Oxidation-Reduction Methods
This type of Alkaline Copper Reduction Test uses arsenolmolibdate
Nelson-Somogyi
Oxidation-Reduction Methods
Principle: Yellow ferricyanide is converted to a colorless ferrocyanide by glucose (e.g. Hagedorn Jensen)
Alkaline Ferric Reduction
Condensation Methods
Principle: The ability of glucose to form glycosylamine and Schiff bases with aromatic amines
Ortho-Toluidine (Dubowski) Method
Condensation Methods
Main reagent: Hot acid or Glacial acid solution
End product: Colored compound
Ortho-Toluidine (Dubowski) Method
Condensation Methods
The Ortho-Toluidine (Dubowski) Method is not only positive for glucose but also for what 2 sugars? (these can interfere with results)
Galactose and Mannose
Enzymatic Methods
This method measures the beta-D-glucose through the use of mutaratose which converts the alpha-D-glucose to beta-D-glucose (indirect measurement of alpha-D-glucose)
Glucose Oxidase Method
Enzymatic Methods
Enzymatic tests act on glucose only and they do not react on other reducing sugars making enzymatic tests what?
Specific
Enzymatic Methods
How many enzymes does the Glucose Oxidase Method use and what are those?
- Glucose Oxidase
- Peroxidase
Enzymatic Methods
What are the 2 products of the glucose oxidase method?
Gluconic acid and Hydrogen Peroxide
Enzymatic Methods
How are Gluconic acid and Hydrogen Peroxide measured, what are the 2 methods?
Using Electrodes and Chromogen
Colorimetric Method - Chromogen
Polarographic Method - Electrode
Enzymatic Methods
Hydrogen peroxide will react with phenol and 4-aminoantipyrine through peroxidase to produce what dye?
Quinoneimine Dye (aka Oxidized Chromogen Substance) and water
Enzymatic Methods
Glucose Oxidase Methods can measure glucose levels from what body fluid?
CSF
Enzymatic Methods
False increase or decrease for the Glucose Oxidase Method?
Bleach
False increase
Enzymatic Methods
False increase or decrease for the Glucose Oxidase Method?
Bilirubin
Uric Acid
Ascorbic Acid (a non-glucose reducing substance)
False decrease
Enzymatic Methods
The most specific glucose method because of the reagent (G6PD), an enzyme specific to G6P that is only produced through glucose
Hexokinase
Enzymatic Methods
Hexokinase is a reference/standard method because it is able to measure all forms of what?
Glucose
Enzymatic Methods
What is the specimen of choice using heparin, EDTA, fluoride, oxalate, and citrate for Hexokinase?
Serum or Plasma
Enzymatic Methods
Hexokinase values are falsely decreased in the presence of what 2 substances as they compete with G6P?
Hgb and Bilirubin
Enzymatic Methods
Glucose with ATP will be acted upon by hexokinase which will produce what (2)?
G6P and ADP
Enzymatic Methods
When G6P is acted upon by G6PD in the hexokinase method, it becomes what?
6-phosphogluconate (with the coenzyme NAD, converted to NADH)
Is measured photometrically at 340nm
Enzymatic Methods
This method involves generated NADH which is proportional to the glucose concentration (the enzyme acts on glucose and uses NADH as a coenzyme)
Glucose Dehydrogenase Method
Note: Mutaratose can be used to shorten the time to reach equilibrium
Enzymatic Methods
This method is important for establishing correct insulin amounts; a strip contains glucose oxidase, peroxidase, and chromogen (it changes color depending on the amount of glucose)
Dextrostics
Enzymatic Methods
This measures B-D glucose which is effective to use in reducing the rate of diabetic complications
Dextrostics
Tests for Hyperglycemia
- The specimen can be collected any time of the day
- Useful for insulin shock, hyperglycemic ketonic coma, and emergency cases
Random Blood Sugar (RBS)
Tests for Hyperglycemia
What is the normal and hyperglycemic range for Random Blood Sugar?
Normal: < 140mg/dL
Hyperglycemic: ≥ 200 mg/dL
Tests for Hyperglycemia
Done after 8-10 hours of fasting to diagnose DM and GDM (measures glucose homeostasis)
Fasting Blood Sugar (FBS)
Tests for Hyperglycemia
What is the hypoglycemic and hyperglycemic range for Fasting Blood Sugar?
Hypoglycemic: < 50 mg/dL
Hyperglycemic: ≥ 126 mg/dL
Tests for Hyperglycemia
What is the normal and hypoglycemic onset range for Fasting Blood Sugar?
Normal: 70-100 mg/dL
Onset of Hypoglycemia: 50-55 mg/dL
Tests for Hyperglycemia
- Useful for monitoring glycemic control
- Blood glucose is determined 2 hours after a meal
- Not used to diagnose DM but used to determine if a patient with DM has good control of their sugar
2-Hour Post Prandial Blood Sugar (PPBS)
Tests for Hyperglycemia
What are the ranges for good and poor glycemic control for the 2-Hour Post Prandial Blood Sugar Test?
Good: < 130 mg/dL
Poor: ≥ 140 mg/dL
Tests for Hyperglycemia
- This is a multiple blood sugar test as it involves the collection of blood from a patient multiple times depending in the request of the physician
- Aids in the diagnosis of DM
- Determines how well the body metabolizes glucose over a given time required
Glucose Tolerance Test (GTT)
Tests for Hyperglycemia
What is the hypoglycemic value for the Glucose Tolerance Test?
≤ 50 mg/dL
Tests for Hyperglycemia
What are the ranges for the following manifestations in the Glucose Tolerance Test?
- When the 3P’s appear
- Severe polydipsia
- Critical value for blood glucose (needs insulin)
- ≥ 200 mg/dL
- ≥ 300 mg/dL
- ≥ 400 mg/dL
Requirements for Glucose Tolerance Tests
The patient should be (blank) as carbohydrates deplete during bedrest and inactivity
Ambulatory