Reviewer's report
Title:Tryptophan degradation in Irritable Bowel Syndrome: Evidence of
indoleamine 2,3-dioxygenase activation in a male cohort.
Version: 1Date:14 July 2008
Reviewer: Sylvie Bradesi
Reviewer's report:
Major Compulsory Revisions
In this study, the plasma levels of tryptophan and its metabolites were assessed
in a male IBS cohort (n=10) and healthy controls. Results indicate increased
levels of kynurenine and neopterin and decreased levels of kynurenic acid in IBS
patients compared with controls. These data are preliminary observations for the
study of the altered tryptophan metabolism in IBS. The limited data and
limitations of the study are clearly stated.
In the discussion, it is stated that plasma kynurenine levels and
kynurenine/trytophan ratio are higher in IBS patients "providing compelling
evidence of increased tryptophan breakdown". This statement in in contrast wih
the actual data showing that tryptophan levels are not altered in IBS patients.
Although, it is briefly discussed later in the discussion, conclusions should be
consistent throughout the mnuscript.
Minor Essential Revisions
the nature of the samples whould be indicated in the abstract
Discretionary Revisions
The authors indicate that interferon gama levels could not be reported because
they were below the limit of quantitation of the analysis method. Could a different
analysis method be used to assess the current samples for interferon gamma?
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
Statistical review: Yes, but I do not feel adequately qualified to assess the
statistics.
Declaration of competing interests:
I declare that I have no competing interests
Reviewer's report
Title:Tryptophan degradation in Irritable Bowel Syndrome: Evidence of
indoleamine 2,3-dioxygenase activation in a male cohort.
Version: 1Date:14 July 2008
Reviewer: Sylvie Bradesi
Reviewer's report:
Major Compulsory Revisions
In this study, the plasma levels of tryptophan and its metabolites were assessed
in a male IBS cohort (n=10) and healthy controls. Results indicate increased
levels of kynurenine and neopterin and decreased levels of kynurenic acid in IBS
patients compared with controls. These data are preliminary observations for the
study of the altered tryptophan metabolism in IBS. The limited data and
limitations of the study are clearly stated.
In the discussion, it is stated that plasma kynurenine levels and
kynurenine/trytophan ratio are higher in IBS patients "providing compelling
evidence of increased tryptophan breakdown". This statement in in contrast wih
the actual data showing that tryptophan levels are not altered in IBS patients.
Although, it is briefly discussed later in the discussion, conclusions should be
consistent throughout the mnuscript.
Minor Essential Revisions
the nature of the samples whould be indicated in the abstract
Discretionary Revisions
The authors indicate that interferon gama levels could not be reported because
they were below the limit of quantitation of the analysis method. Could a different
analysis method be used to assess the current samples for interferon gamma?
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
Statistical review: Yes, but I do not feel adequately qualified to assess the
statistics.
Declaration of competing interests:
I declare that I have no competing interests
Please review this paper.
user
Reviewer's report
Title:Tryptophan degradation in Irritable Bowel Syndrome: Evidence of
indoleamine 2,3-dioxygenase activation in a male cohort.
Version: 1Date:14 July 2008
Reviewer: Sylvie Bradesi
Reviewer's report:
Major Compulsory Revisions
In this study, the plasma levels of tryptophan and its metabolites were assessed
in a male IBS cohort (n=10) and healthy controls. Results indicate increased
levels of kynurenine and neopterin and decreased levels of kynurenic acid in IBS
patients compared with controls. These data are preliminary observations for the
study of the altered tryptophan metabolism in IBS. The limited data and
limitations of the study are clearly stated.
In the discussion, it is stated that plasma kynurenine levels and
kynurenine/trytophan ratio are higher in IBS patients "providing compelling
evidence of increased tryptophan breakdown". This statement in in contrast wih
the actual data showing that tryptophan levels are not altered in IBS patients.
Although, it is briefly discussed later in the discussion, conclusions should be
consistent throughout the mnuscript.
Minor Essential Revisions
the nature of the samples whould be indicated in the abstract
Discretionary Revisions
The authors indicate that interferon gama levels could not be reported because
they were below the limit of quantitation of the analysis method. Could a different
analysis method be used to assess the current samples for interferon gamma?
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
Statistical review: Yes, but I do not feel adequately qualified to assess the
statistics.
Declaration of competing interests:
I declare that I have no competing interests
assistant