Review for 10.1186/s12876-016-0543-z (2016)

Reviewer ’s report  
 
Title: Role of vitamin D3 combined to alginates in preventing acid and oxidative injury in  
cultured gastric epi thelial cells  
 
Version: 1 Date: 28 Apr 2016  
 
Reviewer: Thomas Wex  
 
Reviewer's report:  
 
The manuscript fits in general to the scope of the journal, but has several shortcomings that need 
to be addressed.  
 
 
 
1. Authors used 1 gastric cell line treate d with VitD and an alginate and analyzed cellular 
functions as proliferation and expression of certain molecules. The study design does not 
allow any statement concerning injury, damage or inflammation, since these processes 
require tissue or ex vivo studi es. The authors need to limit their conclusions on their own 
data. Any statement concerning e.g. protective functions in stomach …, cannot be 
concluded and need other study (animal or ex vivo studies). Data presented do not allow 
any statement about Grisu in context to gastric physiology; this question should be 
answered by appropriate animal models or clinical studies.  
 
 
 
2. Authors need to discuss VitD concentration used in context to physiological 
concentrations. Authors used PPI, but this drug is a prodr ug. How did the authors check 
the active metabolite?  
 
 
 
3. The presentation of study design and data is partially confusing and makes it difficult to 
put data of the different analyses together. Authors should provide a scheme for 
experimental settings inclu ding their time periods analyzed. In the current manuscript, the 
authors "jump" between different time sets up to 24h vs. short time periods up to 90mins. 
For several figures (e.g. Fig.5), the time period analyzed is not presented. Authors should 
limit the ir primary data to most relevant ones and focus on identical time periods. 
Extensive sub analyses between subgroups (e.g. Fig. 4 and 7) should be omitted; authors 
need to focus on their major findings.  
 
 
 
4. Figure 1 and 2 describe "numbers of adherent cells " but show relative values in "%". 
What is the basis on which the relative proportion is calculated?  
5. Quality of figure 8 (immunohistochemistry) is not sufficient for publication. Figures 
providing overview (several hundred cells) including magnifications are needed to allow 
assessment by readers. Since VitD receptor is playing a major role, transcript analysis 
should be included.  
 
 
 
6. There are numerous of typos and other mistakes; authors should carefully review their 
final manuscript.  
 
There are several sentences, the meaning of which remains unclear (e.g. "This study 
permits …to improve the adhesivity of cells, reducing time of adhesion …"). What does 
improvement mean in this context?  
 
 
 
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
Does the work i nclude the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
 
Yes 
 
Are the conclusions drawn adequately supported by the data shown?  
If not, please explain in your comments to the authors.  
 
No 
 
Are you able to assess any statistics in the manuscript or would you recommend an  
additional statistical review?  
If an additional statistical review is recommended, please specify what aspects require further  
assessment in your comments to the editors.  
 
I am able to assess the statistics  
 
Quality of written English  
Please indicate the quality of language in the manuscript:  
 
Needs some language corrections before being published  
 
 
 
Declaration of competing interests  
Please complete a declaration of competing inter ests, considering the following questions:  
 
1. Have you in the past five years received reimbursements, fees, funding, or salary from an  
organisation that may in any way gain or lose financially from the publication of this  
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose  
financially from the publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently applying for any patents relating to the content of the  
manuscript?  
 
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds  or has applied for patents relating to the content of the manuscript?  
 
5. Do you have any other financial competing interests?  
 
6. Do you have any non -financial competing interests in relation to this paper?  
 
If you can answer no to all of the above, write 'I declare that I have no competing interests' 
below.  If you r reply is yes to any, please give details below.  
 
'I declare that I have no competing interests'  
  
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