Bob
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Transcription of sections of Alter and Lo presentations
I posted this on another thread on a different subject, so I thought I ought to copy it onto this thread...
Demystifying Medicine - Chronic Fatigue Syndrome: Is there a virus?
http://videocast.nih.gov/Summary.asp?File=16477
I've watched some of the video, and I've transcribed the most interesting sections that I've watch so far.
Some of Lo's presentation is a bit disjointed, towards the end of the quote, below, but the only places that i've missed out any text is in places where i've placed 3 dots (...).
I've bolded the most interesting bits.
Transcription of Shyh-Ching Lo presentation:
[83.05]
"So why did many studies have different findings? This is obviously a very challenging question...
...
"...and the way the clinical sample is prepared, and the processing of this, all can make a difference.
[83.45]
And even more possible to me is that there is a variation of the PCR protocol, although everybody says we are following the same PCR assay, but if you look into all the detail, the cycles are different, [indiscernable] temperature slightly different, magnesium concentration slightly different;
all of this, we really don't know how much that's going to make a difference.
Today the topic is, is there a virus or not? is the virus responsible, or the causative agent of this, or not?
That's all very far away at the present time because, when we are looking at this, we obviously are dealing with a very low rate [or 'grade'?] of infection - a very low copy number in the blood,
and many of these difference can certainly result in the PCR disparities,
and i just want to mention... the NIH obviously, the NHLBI's, is looking into this, and have this sample, coded sample, sent to different laboratories, and to test it,
and this is the clinical [or 'critical'?] panel, the CDC's result,
and obviously ... the four of the patients,
and depends how the sample is being processed,
how long the delay of the processing of the sample, and the results are obviously different;
some are negative and some are positive,
so this is obviously, they also continue to look into this and try to solve is there any processing of the sample make a difference?
..."
[85.30]
http://videocast.nih.gov/Summary.asp?File=16477
I posted this on another thread on a different subject, so I thought I ought to copy it onto this thread...
Demystifying Medicine - Chronic Fatigue Syndrome: Is there a virus?
http://videocast.nih.gov/Summary.asp?File=16477
I've watched some of the video, and I've transcribed the most interesting sections that I've watch so far.
Some of Lo's presentation is a bit disjointed, towards the end of the quote, below, but the only places that i've missed out any text is in places where i've placed 3 dots (...).
I've bolded the most interesting bits.
Transcription of Shyh-Ching Lo presentation:
[83.05]
"So why did many studies have different findings? This is obviously a very challenging question...
...
"...and the way the clinical sample is prepared, and the processing of this, all can make a difference.
[83.45]
And even more possible to me is that there is a variation of the PCR protocol, although everybody says we are following the same PCR assay, but if you look into all the detail, the cycles are different, [indiscernable] temperature slightly different, magnesium concentration slightly different;
all of this, we really don't know how much that's going to make a difference.
Today the topic is, is there a virus or not? is the virus responsible, or the causative agent of this, or not?
That's all very far away at the present time because, when we are looking at this, we obviously are dealing with a very low rate [or 'grade'?] of infection - a very low copy number in the blood,
and many of these difference can certainly result in the PCR disparities,
and i just want to mention... the NIH obviously, the NHLBI's, is looking into this, and have this sample, coded sample, sent to different laboratories, and to test it,
and this is the clinical [or 'critical'?] panel, the CDC's result,
and obviously ... the four of the patients,
and depends how the sample is being processed,
how long the delay of the processing of the sample, and the results are obviously different;
some are negative and some are positive,
so this is obviously, they also continue to look into this and try to solve is there any processing of the sample make a difference?
..."
[85.30]
http://videocast.nih.gov/Summary.asp?File=16477
Slide no. 93:
Why did many other studies have different findings--
There could be a difference in the prevalence of the viral agents among patient groups in different geographic areas.
Heterogeneity of CFS patient groups could be significant.
Variations of clinical sample preparations could affect PCR amplification effectiveness and assay sensitivity.
Variations of PCR protocols, primers, reagents or assay designs may have different sensitivity in detecting the diverse group of MLV-related virus gene sequences in the clinical samples.
The nature of low grade infections with low titers of the virus or low copy numbers of the viral target genes in patients' blood may likely account for the inconsistence and the PCR disparity.