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junior06
2010-Dec-06, 11:28 PM
With regard to the way blood circulates the body. If we start with a single blood cell, we join its' circulatory journey round our body as it enters the cappilaries and veins etc. at say, the tip of our little finger of our left hand. After it completes the whole re-oxegenation process to be re-circulated in our body, is the redistribution of the cell then totally random so that it may end up in our right earlobe for instance. Or does anyone think that the cell could perhaps have a 'memory' homing system which returns it back through the same circuitous route of our body and back to the tip of our little finger of our left hand? Has anyone heard of any experiments which would serve to prove/disprove the idea?

Ronald Brak
2010-Dec-07, 01:11 AM
It doesn't matter where the blood cell might want to go, it's got no way to control where it's going.

Kadava
2010-Dec-07, 04:07 AM
1) The cells have no way of moving or influencing their movement, so it wouldn't matter if they did have a 'memory'.
2) There is nothing significant to distinguish between one blood cell and any other, so no reason for a cell to go want to go to a specific place, or for the blood stream to provide a mechanism for this to happen.
3) I doubt anyone has attempted such experiments, and would be surprised if there was any way currently of performing such an experiment - placing a method of 'tracking' a blood cell on the cell with current technology would grossly interfere with the natural state of the cell so much that an data collected would be meaningless.

Don't let me put you off thinking of things like this, however. Thinking off the wall can sometimes provide interesting ideas. (But never 'bet your shirt' on them.)

pzkpfw
2010-Dec-07, 04:18 AM
I've seen docos where they inject a slightly radioactive liquid into the blood stream to track where it goes - looking for blockages and such.

The stuff spreads everywhere (that it physically can).

kleindoofy
2010-Dec-07, 04:18 AM
Considering that most people donate blood through an artery in the arm, if your question were to be answered positively, then people would be donating "elbow blood" only, which would lead to very lopsided results when used for replacing blood in bleeding patients.

Just imagine losing blood out of a wound in your leg and receiving a transfusion in the hospital, only to watch your arm swell up with surplus "elbow blood" while your leg shriveled due to a lack of "leg blood."

Terribile dictu.

junior06
2010-Dec-07, 04:49 AM
It doesn't matter where the blood cell might want to go, it's got no way to control where it's going.
Fair enough Ronald. However, I'm thinking along the lines of the analgous way there exist in nature, mysterious and unexplainable forces which cause, (salmon for instance), to return exactly to their place of birth, (whether it be in a small stream in Scotland or Canada), after migrating thousands of miles of ocean. There is no conscious reasoning involved, (on the part of the salmon), as to why it returns to it's place of birth.It has no control as to why it will return to that particular spot.( The suspicion so far is that salmon utilise the magnetic fields of the earth to orientate themselves as to their position. CLEVER FISH!) You may reply that you cannot compare the circulation of a particular blood cell in the body with the migration of salmon. And I accept that there may be no scientific correlation between the two.However,what I am saying is that maybe the cell has a disposition to return to a particular type of tissue.And also maybe not.The orignal enquiry was if anyone knew of any experiments which either proved or disproved this idea?

DonM435
2010-Dec-07, 04:58 AM
A red blood corpuscle is a bit less than a complete cell: it has no nucleus. I'd say that makes it even less likely to somehow store its history.

junior06
2010-Dec-07, 05:13 AM
I've seen docos where they inject a slightly radioactive liquid into the blood stream to track where it goes - looking for blockages and such.

The stuff spreads everywhere (that it physically can).

This pretty much aswers the question! I cant help thinking ' What a shame'. Because if the idea had been correct, it could have had a very significant bearing on the issue of tissue rejection with regard to organ transplants.

TrAI
2010-Dec-07, 05:38 AM
Yes, I believe the red blood cells are moved along with the blood, so it is rather random where they go.

Of course, if we were talking about the white blood cells, some of them do have the ability to move by their own power, and will approach areas where the density of certain molecules is high. For instance, macrophages will approach and ingest cells that have certain intracellular molecules outside their membranes, as it indicates that something is wrong with the cell.

Torsten
2010-Dec-07, 06:48 AM
(The suspicion so far is that salmon utilise the magnetic fields of the earth to orientate themselves as to their position. CLEVER FISH!)

I realize this is a tangent, but thought I'd add that while magnetic orientation may play a role in the ocean phase (biogenic magnetite has been found in some species), olfactory imprinting is very important for the final homing in fresh water. You might find this paper interesting:

HOMING IN PACIFIC SALMON: MECHANISMS AND ECOLOGICAL BASIS (http://people.uncw.edu/lemas/courses/Dittman%20and%20Quinn,%201996.pdf)

Jens
2010-Dec-07, 07:05 AM
This pretty much aswers the question! I cant help thinking ' What a shame'. Because if the idea had been correct, it could have had a very significant bearing on the issue of tissue rejection with regard to organ transplants.

In a sense, maybe it would be a shame. But on the other hand, think of the major disadvantage it would have, as brought up by keindoofy! If you donated blood from your left arm, it would go to the left arm of the person receiving the transplant, and they'd still die from the bleeding because the red blood cells would go to the wrong place!

mfumbesi
2010-Dec-07, 07:50 AM
Considering that most people donate blood through an artery in the arm, if your question were to be answered positively, then people would be donating "elbow blood" only, which would lead to very lopsided results when used for replacing blood in bleeding patients.

Just imagine losing blood out of a wound in your leg and receiving a transfusion in the hospital, only to watch your arm swell up with surplus "elbow blood" while your leg shriveled due to a lack of "leg blood."

Terribile dictu.

Well this just made my day...LOL

geonuc
2010-Dec-07, 09:37 AM
This pretty much aswers the question! I cant help thinking ' What a shame'. Because if the idea had been correct, it could have had a very significant bearing on the issue of tissue rejection with regard to organ transplants.

I don't see how the injection and subsequent dispersal of radioactive material answers your question. Yes, it shows how the blood is mixed in the circulatory system, but, as a thought experiment, you were supposing that the red blood cells had some mechanism to prefer one path over another. The injected radioactive material is not composed of red blood cells.

Ronald Brak's initial response contains your answer.

Strange
2010-Dec-07, 09:56 AM
Fair enough Ronald. However, I'm thinking along the lines of the analgous way there exist in nature, mysterious and unexplainable forces which cause, (salmon for instance), to return exactly to their place of birth, (whether it be in a small stream in Scotland or Canada), after migrating thousands of miles of ocean.

I wouldn't say there were "mysterious and unexplainable forces" involved. We have already understood most (if not all) of the mechanisms involved. As for why the ability to navigate so precisely? I assume that they need to get back to somehwere favorable for spawning and where they will find others of their species. If you have the "technology" (biologically speaking) to get close to where you came from, then it is probably not significantly different to get back to exactly where you came from.


It has no control as to why it will return to that particular spot.

Careful. You are mixing two differnt things here. They have no choice but to return, but they are in control of getting there.


You may reply that you cannot compare the circulation of a particular blood cell in the body with the migration of salmon.

I would argue exactly that. Especially as red blood cells barely qualify as living cells.

junior06
2010-Dec-07, 06:14 PM
Considering that most people donate blood through an artery in the arm, if your question were to be answered positively, then people would be donating "elbow blood" only, which would lead to very lopsided results when used for replacing blood in bleeding patients.

Just imagine losing blood out of a wound in your leg and receiving a transfusion in the hospital, only to watch your arm swell up with surplus "elbow blood" while your leg shriveled due to a lack of "leg blood."


This answer is brilliant. It pretty much shows up the absurdity of my original question. Although in my defence, I originally thought that if there was any legitemacy in the idea at all, that it would be of great significance to the issue of tissue rejection in organ transplants. The ' homing memory' of the cell I was referring to would be vaguely analgous to the memory which proponents of homeopathy say exist in the molecules of their preparations and which do not require said molecules to possess any ability to influence their movement.

However, I would like to keep this thread open meantime by posing another not unrelated 'blood' question as follows:
My wife is an insulin dependant diabetic.She checks the sugar levels in her blood by using a monitor. This obviously tells her what her sugar levels are at that specific time. However, she has suffered a couple of episodes of hypoglycaemia ( low blood sugar). This is due to the fact that the monitor does not show, (for example), 'Blood reading is 6, BUT IS COMING DOWN/UP', as the case may be.
The question I would like to ask is: Could there be a constituent in the blood at the time it is taken which would indicate that, although blood sugar levels are presently such and such, it is also presently going up/down? And which could be incorporated in the monitoring machine? I am thinking along the lines of blood ph levels perhaps.Or the presence of a chemical constituent which is altered depending on a presently rising or falling blood sugar level?

Jens
2010-Dec-08, 05:01 AM
It's an interesting idea. The only sensible way that I can think of is to allow the instrument to take two measurements, perhaps at a short interval (say a second or whatever), and then compare the two and see if there is a trend. I don't think it would be easy to come up with a simple marker because I think there are many factors that would influence blood sugar.

rigel
2010-Dec-08, 08:12 PM
It is the sugar being analyzed, not the blood cell. The sugar would be even less likely to know where it has been or it;s concentration.

junior06
2010-Dec-08, 11:11 PM
It is the sugar being analyzed, not the blood cell. The sugar would be even less likely to know where it has been or it;s concentration.

I don't understand the relevence of what you are saying, to the subject matter being discussed. Contrary to what you state, IT IS the blood sample which is being analysed by the monitor, (and the sugar level therein), as it appears at the time it is taken. The main issue is if there is any difference which could be detected between a blood sample taken as the sugar level is coming down and a sample where the sugar level is going up?.

Jens
2010-Dec-09, 01:34 AM
The main issue is if there is any difference which could be detected between a blood sample taken as the sugar level is coming down and a sample where the sugar level is going up?.

If this helps, this Wikipedia page (http://en.wikipedia.org/wiki/Blood_sugar_regulation#Hormones_that_influence_blo od_glucose_level) may help you understand why it's complicated. There are hormones that cause plasma glucose level to rise, but the glucose level is also raised (obviously!) by eating food. So somehow the test would have to not only measure all those hormones (not so easy to do) but also somehow know whether the person is eating or not. It's not really practical is probably the best answer. I suppose you could try what I suggested, to take two readings closely timed and find a trend, but even that would be problematic because suppose the person is hungry (glucose is falling) but has just eaten a chocolate bar (and the glucose will soon rise)?

Nick Theodorakis
2010-Dec-09, 02:44 AM
There research as well as diagnostic studies in which RBCs are removed, labeled with a fluorescent, radioactive, or some other tracer, and reinjected into an animal or patient in order to study various aspects of blood circulation. I can't imagine they would work very well if the blood cells "wanted" to return to some specific area.

Nick

rommel543
2010-Dec-09, 05:02 PM
Is that not why the machines are suppose to be used only on one person? I was sure that the new machines kept track of past levels and therefor were capable of telling you if you blood sugar was rising or falling. Plus as Jens mentioned, it's also up to the person to logically think about their readings. It takes about 1/2 hr for nutrients to circulate through the body after ingestion. So if you eat something high in sugar then take the reading 5 minutes later you're not going to get the same measurement than if you take it 1/2 hr later. Also if you haven't eaten anything substantial in the last 6 hours, a hand-full of carrot sticks isn't going to do much for you.

captain swoop
2010-Dec-09, 07:31 PM
Considering that most people donate blood through an artery in the arm, if your question were to be answered positively, then people would be donating "elbow blood" only, which would lead to very lopsided results when used for replacing blood in bleeding patients.

Just imagine losing blood out of a wound in your leg and receiving a transfusion in the hospital, only to watch your arm swell up with surplus "elbow blood" while your leg shriveled due to a lack of "leg blood."

Terribile dictu.

Like Tony Hancock in 'The Bood Doner'

Hancock: How much do you want?
Doctor McTavish: A pint, of course.
Hancock: A pint? Have you gone raving mad? You must be joking.
Doctor McTavish: A pint is a perfectly normal quantity to take.
Hancock: You don't seriously expect me to believe that. I came here in all good faith to help my country. I don't mind giving a reasonable amount, but a pint? That's very nearly an armful. I'm not walking around with an empty arm for anybody.

junior06
2010-Dec-09, 11:16 PM
Like Tony Hancock in 'The Bood Doner'

Hancock: How much do you want?
Doctor McTavish: A pint, of course.
Hancock: A pint? Have you gone raving mad? You must be joking.
Doctor McTavish: A pint is a perfectly normal quantity to take.
Hancock: You don't seriously expect me to believe that. I came here in all good faith to help my country. I don't mind giving a reasonable amount, but a pint? That's very nearly an armful. I'm not walking around with an empty arm for anybody.
I forgot about this sketch. Classic! If Tony Hancock thought a pint of blood was an armful,then regarding my original enquiry, I'm in good company! Maybe I should consider being a comedy script writer?

Jens
2010-Dec-10, 01:35 AM
Is that not why the machines are suppose to be used only on one person? I was sure that the new machines kept track of past levels and therefor were capable of telling you if you blood sugar was rising or falling.

You're talking about something different. The question wasn't about long-term changes in blood sugar levels, but rather short-term changes, like in the space of minutes. The person was concerned about the danger of injecting too much insulin and creating hypoglycemia (a danger with type 1 diabetics).

junior06
2010-Dec-10, 05:11 AM
You're talking about something different. The question wasn't about long-term changes in blood sugar levels, but rather short-term changes, like in the space of minutes. The person was concerned about the danger of injecting too much insulin and creating hypoglycemia (a danger with type 1 diabetics).

Yes, you are correct here Jens.'rommel543', was simply stating the fact,(urelated to the issue in question),that modern monitoring machines retain a record of past blood results. However,there is a common sense workaround solution to the problem which merely involves taking 2 blood samples say, 10/15 mins apart.This will faithfully indicate whether sugar levels are either presently falling or rising.In relation to my wife in particular, she has recenly had to adopt this procedure as she has lost any warning signs,( for various medical reasons), that she is taking a 'hypo'.That notwithstanding, any Type 1 insulin dependant diabetics I have spoke to, have said that any monitoring machine which could indicate a PRESENTLY rising or falling (of their blood sugar level) in the one sample, would be greatly advantageous. ( I suppose it comes down to the fact that anything which reduces the amount of times they have to puncture their skin,would be regarded as most welcome).For anyone who can develop such a monitor,the sky's the limit with regard to its' money making potential. I personally do not have the means at my disposal to research/develop such a machine. However, for anyone out there who does come up with a solution, I would appreciate first refusal on the prototype.

Jens
2010-Dec-10, 05:46 AM
For anyone who can develop such a monitor,the sky's the limit with regard to its' money making potential. I personally do not have the means at my disposal to research/develop such a machine. However, for anyone out there who does come up with a solution, I would appreciate first refusal on the prototype.

I'm sorry to be a bit negative here. But as I stated above, I think it would probably be impractical to develop such an instrument. You can sort of logically think it through like this: (1) it's a well-known problem; you are not the first to discover that type 1 diabetics can half hypoglycemic episodes; (2) as you say, it would be profitable, and there are pharmaceutical companies with lots of research money who would no doubt develop such a device if possible, and (3) they have not done so. To me that indicates that it's probably not a practical idea.

I really think the issue here is the complexity of the problem. For example, a diabetic may have just had a chocolate bar, and takes a reading that indicates insulin is rising, so goes ahead and takes a big dose of insulin. Then ten minutes later starts playing some strenuous sport. Suddenly you have a problem, and the meter would have no way of knowing that the person was planning to do a marathon or whatever.

I think the real practical way of doing what you want to do is to develop something like an implanted device that continuously monitors the glucose level. And guess what, it turns out they are in clinical trials (http://medhealth.tmcnet.com/topics/medical-devices/articles/93508-implantable-glucose-sensor-lasts-more-than-year.htm)! (I swear I had no idea of this, but somehow had a feeling I wouldn't have been the first to think of it.) So who knows, this could be good news for your wife.

Donnie B.
2010-Dec-12, 03:13 PM
Now, the real trick would be to find a way to measure glucose levels without breaking the skin. If you could figure that out you'd improve the lives of millions, and probably become richer than Bill Gates in the process.

Nick Theodorakis
2010-Dec-13, 01:50 AM
Now, the real trick would be to find a way to measure glucose levels without breaking the skin. If you could figure that out you'd improve the lives of millions, and probably become richer than Bill Gates in the process.

There is a continuous glucose monitoring system, although it does use a small sensor implanted under the skin, so it does "break the skin" once. See:

http://diabetes.niddk.nih.gov/dm/pubs/glucosemonitor/index.htm

Searching google or PUBMED for "noninvasive blood glucose monitoring" indicates they have been testing of systems using IR or other types of spectroscopy for several years but the lack of any product suggests they have not been satisfactory.

Nick

TrAI
2011-Jan-15, 02:01 PM
Now, the real trick would be to find a way to measure glucose levels without breaking the skin. If you could figure that out you'd improve the lives of millions, and probably become richer than Bill Gates in the process.

Well... There is the process called reverse iontophoresis, basically it means using a small electric flow to extract certain molecules through the skin for measurement. Apparently there was a device called the glucowatch that used this process, and there is this concept for a glucose monitor wristband (http://www.tuvie.com/glucom-wristband-monitors-your-blood-glucose-levels/).

junior06
2011-Jan-16, 02:05 AM
Well... There is the process called reverse iontophoresis, basically it means using a small electric flow to extract certain molecules through the skin for measurement. Apparently there was a device called the glucowatch that used this process, and there is this concept for a glucose monitor wristband (http://www.tuvie.com/glucom-wristband-monitors-your-blood-glucose-levels/).
The relevent word here is 'concept'. This website is a forum for possible concepts and inventions of the future. When I first read it I nearly fell off my chair. How had I not heard of this invention before? On further reading, it became apparent that it was indeed only a concept. GUTTED!! If you read the comments on this websites forum,it becomes apparent how desperate the people are to purchase the device.(They believe this device is actually available). Step up, the next Bill Gates.

TrAI
2011-Jan-16, 08:49 AM
The relevent word here is 'concept'. This website is a forum for possible concepts and inventions of the future. When I first read it I nearly fell off my chair. How had I not heard of this invention before? On further reading, it became apparent that it was indeed only a concept. GUTTED!! If you read the comments on this websites forum,it becomes apparent how desperate the people are to purchase the device.(They believe this device is actually available). Step up, the next Bill Gates.

Well, I did say it was a concept. The technology is in its early days, the only commercialized product based on this technology I know about was the GlucoWatch (http://www.diabetesuffolk.com/ManagingDiabetes/Glucowatch.htm) I mentioned, It had to be calibrated by a conventional blood sample, and would then monitor the glucose levels non-invasively. Though it wasn't a complete replacement for the traditional testers, it had the ability to log measurements for the last 12 hours, and so could help show glucose level trends, and could be set to give warning of high and low readings. The device did have some problems so it is no longer manufactured.

There are other methods that might be used, impedance spectroscopy(measuring the change in the dielectric properties of the body in response to EM radiation at specific frequencies that target glucose), infrared spectroscopy(measuring the response to infrared light, it is currently used for measuring hemoglobin oxygen levels but might be used for glucose too), and I did see something about monitoring the heat generated by glucose processing, but I don't remember where. Sadly, it seems that no technology is in a mature enough state to be commercially practical at present.

junior06
2011-Jan-17, 12:00 AM
I think any improvement on the present methods of monitoring blood glucose levels by invasive techniques, is many years off. It may prove that this process is the best that can be achieved. ( Short of actually implanting a monitor within the body perhaps). The only other avenue which may be explored, might lie in previous experiments which appear to indicate that cappillary blood flow near the surface of the skin increases when insulin levels are raised. ( I can provide the reference if you really insist).