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Teenage Stranger

Today I am writing about a topic which is on the hearts and minds of many parents, myself included. It is probably one of the most challenging and frustrating periods that all parents will face at one time or another; in some form or another. The day will come when you will be sitting at your dinner table with your family and become suddenly aware that your son or daughter has been replaced by a stranger. Even though it would seem that little has changed in the day to day activities with the same familiar faces of your family, it will descend on you without warning.

For some parents, the changes may seem gradual. But for others, it may appear as if the only remaining evidence of your dear child are features that federal agents could use to identify through their physical remains. However, what is important to understand is that as your growing child moves through common stages toward adulthood, their behaviors are the sum of their particular environment, both outside and inside their skin.

Between these environmental forces, the least understood and yet most influential by far is the climate within (or under) our skin. It is very complex and beautifully synchronous team of biochemical and molecularly organized structures that operate independently, yet together for the whole body. Everything within the internal environment is there for a reason. Every part from the greatest to the smallest, mobile to fixed, weaved or fragmented has a role and would not be there without serving some purpose. One role which is often a focus of behavioral sciences is that of communication, that is how the parts “talk” to each other. This is where you may have heard the term, “chemical messengers”. This refers to the wide array of signaling methods used to communicate top-down instructions on what to do and when to do it.

One way in which communication is carried out is through a type of “public broadcast message” via hormone influence. Hormones are much like common cell to cell interactions, but hormones target a very wide population of cell sets and stirs various role-specific groups to fulfil a particular job for a particular need. As a system wide message has many important targets, the announcement must be loud, clear and lasting. In other words, unlike a neurotransmitter that makes you move your arm, the message must be loud enough, specific and last long enough to assure every player is on board for the same objective. You could say that it is much like the horns and sirens alerting the city of an oncoming tornado, where emergency crews, support teams and families make the necessary preparations in order to secure wellbeing. The article I will be introducing is about two such hormone messengers, testosterone and cortisol.

Since stress is such a profound issue in adolescence, let us just mention this first. As children develop toward independent and responsible adults, they will have to pass through a very difficult transistion where their world is completely reframed. They understand their environment through the eyes of their parents. They emerge into a a large society of many other indiviuals where they lack significance and meaningfulness beyond “who they are” as children of their parents. It is through their groups and select friends that they become unique as a separate entity, therefore more meaningful and significant. But these associations are not without bruises and bumps to their sprouting young ego. This is often where kids become more abrasive with others especially those in authoriyty and challenge the the important values they were taught from youth. It is important to understand that attitudes and actions are not motivated from a hurtful intention. It is a desparate attempt to become unique in a world of others; to be an indivual and therefore to be special and meaningful. Sometimes, this may even mean having to reject everything and everyone they know close to them just to see what remains, which helps define “who they are”.

In order to better understand magnitude of stress that a teenager faces, we must consider that they are experiencing significant changes in their own physical development and these changes impacts their evolving self regard through family, school and social group dynamics.

When stress is experienced we are wired to prepare for some form of adaptive action. This means our minds and body need to fall back on a base level program in our DNA that is designed for survival in the face of potiential threats. Through “percieved” dangers, our brain relates a message that the pituitary gland must amplify for “full alert” to the entire body. It releases a hormone trigger (ACTH) that quickly stirs the adrenal cortex (along the top of our kidneys) to send out the alert through cortisol.

High levels of cortisol produces a hyperactive sense of “fight or escape”. The body becomes completely dedicated at that point to return to a comfort balance, either through confrontation or avoidance.

Now we shift our spotlight to Testosterone. Yes, ladies you have some of this stuff too. However, it usually is fed forward toward modification as an estrogen precursor. However, this topic is relevant to both genders.

Testosterone fuels our “stress prepared” body toward a direct action. It is aligned and in complete agreement with the cortisol signal, that is to return to a state of comfort. Therefore if there is an action which we may believe to be effective to restore comfort, then such an action is then presented to our “judgement command center” for consideration.
If the level of stress is high, the tentative action, regardless of consequence is more likely to be chosen. If the choice leads to undesired consequences or punishment, then testosterone is postured to remove some of the sting from the hard consequences.

Now for the sake of clarity, consider the following example.

Let us say you were not responsible enough to prepare for a school final exam which was to be administered in class the next day. You were talking with one of your peers and discovered that it was going to be over half of your class grade. You were already fighting to keep your grades up in other classes and knew that a failing grade on the exam would mean you would fail the year. The cortisol would be broadcasting an alert throughout your body. You are feeling a sense of desparation and then think about ANY action to achieve a passing grade.

You believe you are honest and would never consider cheating. Then judgement gets a option which can likely restore balance. Testosterone sends a message. I do not believe in cheating…But..the stakes are high…it is only one time…what if…

That is the mechanism. See how it played out?

Now, one comment. You will see in the article how this scenerio does not end in unethical considerations when either the cortisol is decreased. Translated in biological terms, this means by preparing correctly and responsibly or even by seeing less stress in a course of action, will likely assure choices which are ore alligned to be more ethical and responsible.

In terms of adolescence, it would be better to understand the stressors they have and help them to effectively and responsibly meet their challenges instead of passing judgments on bad behavior. By aligning with their strength we can shoulder them and guide them more effectively. If we only pass judgement on their choices, we add to their wagon of stressors and then become part of the problem and not their strength. In this way, good parents can avoid being responsible for driving their kids into deliquency.

 
 

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This is your Stem Cell

 AuthorGregcard

 

stem_cell

 

It was during my studies in Medical School.  We were covering Histology and Cell Biology.  Many terms were flying around making it difficult to get an adequate grasp of the various cell lines that originate from the Pluripotent Stem cell.  It was amazing to concept to consider. One cell, the all-in-one component, that had no clear identity, yet possessed everything it needed to become ANY cell type the body required.  I sat at a restaurant reviewing my notes when a model came to my head.  I began drawing on napkins when this model emerged.  It has proven useful for many years and helps me understand this subject  better as topics about stem cells, leukemia and anemia are discussed.

Allow me to share a short overview through a series of images I reproduced from those sketches.  Later I will share some defining aspects of this model and how this model proves useful in grasping all Leukemia, stem cell studies, and blood disorders clearly,and easily.


 

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The Top of the Pyramid is the Stem Cell. It is also called Pluripotent, because it has the potential to become ANY cell that the body requires.  Now every cell in the body has your genetic code, in other words every cell reads the same blue prints.  However, these blue prints have many pages, so that each cell at the time of their defining moment will be told what page they should read.  This is made possible by the messages conveyed to each cell. After receiving their primary instruction, they begin to produce small translating proteins governed by a factory inside the nucleus.  These small proteins will help unfold a specific condensed coil of DNA (blueprints) and twist it out in the open sea of transcribing proteins.  These proteins will then start the initial modifications which gives the cell an identity and function. So every cell reads the same DNA, but their identity is determined by what part of the code it reads. Beautiful, isn’t it?

Anyway, back to the model.  You will see three main path directions the stem cell can roll down the pyramid.  It can roll to the right towards the Red Blood cell pathway, to the left towards the Lymphocyte pathway or toward the front which is the Granulocytic pathway.

Now, here allow me to pause and mention that all cells carry their DNA through their lifetime, EXCEPT for Red Blood Cells (RBC).  The reason is because their role is so clearly defined at maturation that they no longer require the blueprints.  Furthermore they do not have the room to carry the unnecessary machinery if they are to use as much space as they can for Hemoglobin, to carry needed oxygen to your tissues and organs.  Their role on life’s stage is about 3 months anyway, so they need to be optimal for a short time before they are recycled.

You may be wondering how the pluripotent stem cell knows which side to roll down? Well, as the cell begins the early stage of development, signals are provided from the instructions of your body needs.  This tells the DNA to unfold just in certain areas which instruct the proteins inside the cell to form small “foot” receptors for cell mobility.  These foot receptors stick outside the cell wall and  snap into certain floor stepping stones which tilt the balance toward that edge.  Then as the cell begins it’s roll down the descending wall, it makes contact on the specified textured side  stones, which provides further signaling to the cell machinery.  This helps to explain how the developing “foot”processes form, directing the undefined character of the cell toward further differentiation and identity.


 

  Lets look at the next slide.

 stemcell_above_lymph

 

 

 

 

 

 

 

 

 

 

In this slide, you are standing above the model. I provided a map to summarize what I have already discussed.


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This slide shows the lymphocytic side of the model.  Notice, that I have labeled a textured stone as CD19.  This is a cytologic marker which is on every lymphocyte. This is an example of the type of stepping stone that helps ambulate the unique foot process of a defining lymphocyte.  As I continue to gather more data, I plan to further develop the stepping stones or cell markers  that characterizes each cell type.

Now as the lymphocyte rolls further down it will differentiate further.  Let us move to that slide.


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Here we have the next branch of maturation for lymphocytes.  They will become either T-cell or B-cells.  Their role is to police infection , but their tasks are different. They may become presenter cells (to show foreign material to infection station, or some even become Killer cells.  These cells are like a Highway Patrol, which frisks passing cells during their travels and pulling random cells over that look suspicious. If there is a cause of concern, the Killer cells have authority to activate a self destruct button on that cell.  This is important as such cells may be  harboring a virus hidden away inside it’s machinery.

Under the right signal conditions, the B-cell proliferates and becomes a Plasma cell.  These plasma cells become powerful micro-factories and takes on the task of generating “target-specific rockets”, designed to eliminate foreign saboteurs. Tons of these special rockets are sent out to move along with the traffic increasing the likelihood of bumping into it’s target, if it exists.   

There are a wide range of important functions here.  I can discuss this in a future blog.

However, I do wish to point out that I made the developmental parts of each lymphocyte branch as stairs for a reason.  Sometimes there are stages in cell development where it is more sensitive to specific infections.Such is the case for Burkitt’s Lymphoma,  It seems to attack B-cells during the intermediate stage of development.  Therefore in including this added feature to my model, it helps me to remember that this set of stairs are clinically significant.


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 The front platform is the  granulocytic side of the pyramid.  The stem cell rolls toward this path because of a signaling messenger call Granulocyte Stimulating Factor (GSF).  As it rolls toward the front it becomes further differentiated into various white cells.  To clarify an earlier point, if GSF is present and the cell rolls this direction, it may receive a signal from Interleukin-5.  If it has the correct receptors, these cells will tilt and drop off as Eosinophils.  I must go but I hope to share more later.  I hope my model proves useful to you the reader..

Thanks for reading.

 

Greg E. Williams, MD

 See Animated Video of this model:

http://youtu.be/wgaQbN2lxpc

 

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