Рũßłїѕђёď åŗțїćłё #3

Brouwer, Ingeborg. 2010. ‘Effect of Animal and Industrial Trans Fatty Acids on HDL and LDL Cholesterol Levels in Humans – A Quantitative Review.’ Accessed April 05, 2013. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2830458/

Effects of Animal and Industrial Trans Fatty Acids on HDL and LDL Cholesterol Levels in Humans- A Quantitative Review:

          Trans fatty acids can be obtained from industrial hydrogenation of vegetable oil and fish oils (artificial trans fatty acids) or from the biohydrogenation from ruminant animals such as cows and sheep (natural trans fatty acids). The consumption of these hydrogenated products results in the increase or decrease of HDL and LDL lipoproteins in the body which places a risk on a person’s heart.

            In this report 39 studies were conducted using persons with controlled diets. Twenty-nine used industrial trans fatty acids, six used ruminant trans fatty acids while seventeen used conjugated trans linoleic acid (CLA). Linear regression analysis was uses to determine if these individuals were affected. The slope of the line for LDL to HDL ration was steeper for trans industrial fatty acids than for ruminant fatty acids or CLA. Statistical analysis was used to compare trans fatty acids with saturated fatty acids.

            The results indicated that there was significant weight loss and gain for some individuals with an increased risk of heart and liver disease. There is a quantitative comparison of the effect of ruminant trans fatty acids and CLA with industrial trans fatty acids on blood lipoproteins in humans. The analysis shows that all three classes of trans fatty acids raise the ratio of LDL to HDL. The effect of ruminant trans fatty acids and CLA on the LDL to HDL ratio was less than that of industrial trans fatty acids. The trans fatty acid with double bonds raised the LDL and lowered the HDL levels of cholesterol.         

            Thus, it was concluded that the removal of all the ruminants trans fatty acids (meat and milk) would lower the total trans fatty acid intake. Further studies need to be conducted to determine if the effects are due to chance. It some countries such as Denmark trans fatty acids are banned from the food industry.  

            This article helped me to better understand trans fatty acids to a larger extent. My knowledge of why trans fatty acids has such a negative impact on our bodies was broadened. Although this substance tantalized our taste buds and increases the shelf life of certain products it is a major component of cholesterol molecules. This as it is known leads to atherosclerosis which leads to heart attacks and strokes.

             I hope that after reading this  blog post you try to change your lifestyle to a more healthier way of living. Remember to exercise regularly, drink 6-8 glasses of water, include a large amount of fresh fruits and vegetables, and keep in mind that what you put into your body will affect you sooner or later.

            Byee!

Video

Understanding Cholesterol…

What is Cholesterol?
Do you know what it is?
Have you ever stopped and wonder how many foods you eat each day that contains this molecule?

Well I am using this video to help you my viewers to understand more about this molecule.
Cholesterol is a waxy, fat like substance found in the blood stream and cells of the body. This naturally occurring substance plays a critical role in the formation of cell membranes and the manufacture of hormones. only a small amount of functions is needed to carry out these functions so the presence of additional cholesterol poses a risk to the body.

How cholesterol works?
This molecule does not dissolve in the blood stream but is transferred in and out of the cell by carriers called low density lipoproteins (LDL) and high density lipoproteins (HDL). When cholesterol increases more lipoproteins is needed to be produced to transfer it across the cell. LDLs are bad because too much of it result in plaque build up in the artery wall which leads to a condition know as atherosclerosis. The arteries are hardened and clogged which can lead to a heart attack or stroke. On the other hand HDL is a good carrier since it aids in the removal of cholesterol from the arteries into the liver and out of the body.

How is cholesterol determined in the body?
A blood test can be done. The levels of cholesterol varies in a person’s age, weight and sex.
An LDL level above 160 is high while an HDL level below 40 is too low. This places someone at risk for plaque build up. 75% of the cholesterol is made in the body while the other 25% is obtained from our diet. It is found in foods such as meat, eggs and liver. Eating less saturated fats from animals is a first step in lowering cholesterol levels and living a healthy life style.

This video was beneficial in helping me understand more about the effects cholesterol. A possible way to better this video is maybe the additional of more pictures to show the effects this molecule has on our body. I enjoyed it sice it was short and to the point.

Enjoy!!!

Video

Growing Up With Galactosemia

The video is about a young boy named Everet who was diagnosed with galactosemia at birth. He has grown up and is still able to survive with the help of his family and changing his lifestyle to accommodate this rare genetic disorder. He is unable to eat any dairy products such as milk, butter and cheese. He avoids foods high in galactose such as beans.
I have learnt more about this disease since it is the first time I ever heard about this disease and its effects.

Video

Sugar is on my mind…haha
This video shows the ten steps in glycolyis. It deals with the breakdown of glucose into its various forms with the aid of the different enzymes to form pyruvate. Hope you enjoyed it like I did. :)

Untitled

Lysine has three ionizable functional groups with the following pKa values:

α-amino group = 9.04

α-carboxylic group = 2.17

R group = 12.48

The R group for lysine is –CH2CH2CH2CH2NH2

(i) Write the equilibrium equations for its three ionizations and assign the proper pKa for each ionization. Show the net charge on the lysine molecule at each ionization stage.

lysine tit

(ii) Calculate the Isoelectric Point (pI):

The pI is the pH at which two amino acid has a net charge of zero (0).

1. Write out equations to show ionisation. Start with the amino acid in its fully protonated form. The pK values increase as you loose H-atoms so start the ionization using the group with the lowest pK value and then you increase as ionization continues.

2. Ensure that pk values are placed above reversible arrows.

3. Calculate the net charge of each molecule by adding the positive charges and subtracting the negative ones.

4. Calculate the pI using the equation below: ( pK1 value is the pk value to the left of the zero net charge and pK2 value is to the right of the net charge of zero).

pI = pk1 + pk2 ⁄ 2

pI = 9.04+12.48/2

pI = 10.76

All my Biochem Bloggers please note this titration steps for exam. It has been confirmed that it is going to come!!! Don’t say I didn’t warn you.lol.

Competitive vs Non-competitive Inhibition:

Two types of reversible inhibition are:

  • Competitive

  • Non-competitive

COMPETITIVE INHIBITORS:

This inhibitor binds to the same site as the substrate. It therefore competes since both substrate and inhibitor are similar in shape.

Effect on Vmax: it is the same velocity in the presence of competitive inhibitors.

Effect on Km: the Michaelis constant increases in the presence of competitive inhibitors.

NONCOMPETITIVE INHIBITORS:

Occurs when the inhibitor binds to a free enzyme or enzyme substrate complex preventing the substrate from binding to its active site.

Effect on Vmax: it decreases in the presence of noncompetitve inhibitors.

Effect on Km: the Michaelis constant is unchanged in the presence of noncompetitive inhibitors.

Graph 1 showing Michaelis – Menten curves for competitve and noncompetive inhibition:

1

Graph 2 showing Lineweaver – Burk plots for competitve and noncompetive inhibition:

2

References:

http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/E/EnzymeKinetics.html