Hi All,

This is a fantastic use case, where semantically formal annotations will be absolutely required in order to resolve even a portion of the questions listed, if they are to cast a wide net across all the relevant information - e.g., primary data repositories (individual, as well as data warehouses and federated data resources), the literature, clinical trial reports, clinical records, etc.

This is exactly what I was trying to get at back in the late summer on the BIOONT Wiki. The idea was to go into the literature to pull together several relevant papers collectively providing findings related to a broader question in neurodegenerative illness. We'd then go through the papers - just at a high-level - and pick out the essential findings, expressing them using the PATO formalism http:// www.bioontology.org/wiki/index.php/PATO:Main_Page). This requires expressing the observation made in the context of ontologically defined entities from the molecular on up through behavior. In performing this task, one must determine which of the available community ontologies can cover the required domains. It also helps to provide a clear categorical description of the type of data repositories that must be integrated and where they fit into the overall semantic landscape. BioRDF would then define what exists for those domains that is publicly accessible - as is outlined somewhat in the BMC Bioinformatics manuscript.

I apologize for missing the meeting today. I was ill and am slowly coming back.

Re: the BIRN Use Cases relevant to the HCLSIG Demo:
As I mentioned in the TCon last Thursday, I've been working with the BIRN Ontology Task Force to assemble a public page providing the many use cases assembled by various BIRN research projects - all of which focus on drawing together information from disparate sources to address scientific questions related to Alzheimer's Disease, Schizophrenia, Parkinsonism, and MS (with Huntington's Disease and Autism being introduced over the past year or so). Given the heavy neuroimaging focus on BIRN, many of the details of these use cases relate to seeking correlations between segmented geometries in various MRI, MRI/DTI, fMRI, light-microscopic, and EM images and other related data extending from genotype & gene expression on through behavioral & cognitive assessments. Many of the active research projects in the BIRN involve the generation and analysis of neuroimaging data and associated experimental assessments - data that may be acquired in one lab, processed in another, and ultimately used for analysis by many. Already there are 100s of TB of data on the BIRN infrastructure, though imaging researchers will recognize this is quite small, given that includes raw image data, and data in various stages of processing and analysis.

BIRN's goal is to provide a high-capacity, high-throughput infrastructure to support this manner of collaborative research and to host the results for public use. The components assembled to date consist of the following: 1) a distributed query mediator posting queries across the 60+ site source data repositories - many of which are RDBMS-based. A source repository needs to "register" with the mediator in order to be accessible during query resolution 2) an ontology (BIRNLex) to provide a shared, formal expression of the required biomedical entities and processes that will support machine-parsing of semantic assertions defined on data via ontology- based annotation; note that the BIRN ontology draws heavily on the community ontology efforts throughput biomedicine, to avoid duplicating effort and ensuring maximal semantic integratability 3) a storage grid (based on SRB) that includes a metadata catalog which can be linked to the mediator; when a query result tuple points to a binary object such as a 2D, 3D, or 4D image set stored on SRB, this can be returned to the querying application - whether its an interactive, end-user oriented query front end, or an automated process, such as a distributed image processing pipeline 4) an XML Schema (XCEDE) and associated toolset for uniform exchange of data. This can help to simplify and standardize the way in which the 3 resources above are put into practice, as well as provide a uniform view of BIRN-hosted information to the greater public.

As I mentioned before, the BIRN project as a whole has focussed on providing this required infrastructure, tools, and data standards for the current BIRN participants. Though the goal is for all of these resources to be publicly available, human resource limits have meant what is currently available via the BIRN infrastructure to the public is very limited. There is an effort underway to address this issue. We on the Ontology Task Force have made our current draft ontology available publicly. What is being assembled in that ontology is designed to support the use cases identified by the participating research labs. These are grouped under "testbed" categories - two human focused - Morphometry BIRN (MRI & DTI-MRI) and Function BIRN (fMRI) - and one focussed mouse models of neurodegenerative disease - Mouse BIRN. More recently, there have been efforts to include neuroimaging projects associated with the various North American primate centers, which brings in macaque, a species used extensively for various structure/function studies in the brain (see www.cocomac.org).

As a preliminary to assembling a comprehensive and coherent listing of the use cases from throughout BIRN, I've assembled pointers to "some" of the use cases on the public BIRNLex page:
                http://xwiki.nbirn.net:8080/xwiki/bin/view/+BIRN-OTF-Public/Home

        I would say the following are all worth looking through:

1) The recent Morphometry BIRN use case listed there on that page provides a since of the comprehensive nature of the questions being addressed in that project - in this particular case various ways of determining whether diagnosed depression can effect the onset and severity of AD. 2) The link to the Function BIRN Use Cases below the table on that page provides a sense of the complex imaging & image associated metadata one must semantically represented in order to make effective use of fMRI data to answer a broad range of questions questions related to the structure & function (or malfunction) of the nervous system. 3) The "3 BASIC LEVELS OF DATA MEDIATION" link, since it was assembled by the group in Mouse BIRN that works on the alpha- synuclein mouse model of PD.

There are many, many more use cases than these, but it will probably be a while before I'm able to do better than this. BIRN is large organization, and I'd want to make certain along with the Use Cases, we provide information on which are actually being pursued as research questions by BIRN-associated projects, so as to be able to indicate there is data related to that use case accumulating on the BIRN infrastructure, and the BIRN ontology has covered the relevant knowledge domains.

        I hope this is helpful.

I will try to find time soon to get to more of the BIRN use cases, especially those supported by data and ontological graphs and directly related to the current PD use cases Don, Kei and others have included in the BMC Bioinformatics manuscript.

Cheers,
Bill
        
On Dec 11, 2006, at 11:03 AM, June Kinoshita wrote:


Hi Susie,

Elizabeth, Gwen and I have been working on a fairly elaborate use case. To help the con call participants follow it, we've prepared this simple outline:

A hot topic in AD therapy is immunization - developing a vaccine or antibody that will neutralize amyloid-beta peptide (Abeta), the putative toxic agent that is hypothesized to cause Alzheimer disease.

Problem: The first clinical trial was halted because patients developed encephalitis.

Question 1: Why did some patients but not all get encephalitis?
Question 2: There is debate about whether Abeta is the toxic entity; but assuming it is, what form is toxic? Abeta has been reported as monomers, dimers, soluble oligomers, protofibrils, insoluble fibrils.

Research Challenge: If immunization therapy is to work, i.e. it clears Abeta from the brain and does not cause encephalitis, one needs to 1) identify the exact toxic form, 2) understand cause of encephalitis (brain inflammation)

In our use case, an investigator reads about the discovery of a new form of Abeta, called Abeta*56, that is reported to cause memory impairment in a mouse model of AD.

Is Abeta*56 a good target for immunization therapy?

Question: Is there human data to support that Abeta*56 is involved.

A query of PubMed finds a paper reporting that a form of Abeta with identical molecular weight, called ADDL, is elevated by as much as 70-fold in human AD patients' cerebrospinal fluid. A hypothesis about ADDL causing memory loss in AD is posted on Alzforum.

Question: By what mechanism might Abeta*56 cause memory loss?

The ADDL Hypothesis on Alzforum suggests that ADDL (= Abeta*56?) disrupts LTP.

Question: What is the mechanism of LTP, in a part of the brain that is relevant to AD?

The literature indicates CA1 hippocampal neurons, and A- and D-type K channels are involved in LTP. BrainPharm data state that CA1 hippocampal neurons have A-channels. What's more, the A-current is reduced by Abeta.

Question: Would an antibody directed against ADDL / Abeta*56 restore A-current in the mouse model hippocampal neuron (e.g. in an organotypic slice prep)?

A query locates an antibody to ADDL and where to obtain it.

Question 2 is what determines vulnerability to encephalilitis among immunized patients?

A literature search finds interferon-gamma (INFG) may be a player. This comes from both mouse and human trial data (need to check this).

Question: Do polymorphisms in INFG, or differences in INFG regulation, correlate with inflammatory response to vaccine?

Question: Why did the mouse models not develop encephalitis in preclinical studies?

Our investigator queries pathway databases to identify the gene network involved in IFNG regulation, and also SNP databases for differences between mouse strains, mouse and human. He narrows down a group of genes and queries the AlzGene database to see if any gene association studies have shown a correlation between any of these genes and AD risk.

Our investigator proposes a study to genotype participants in the failed vaccination trial to find out whether the encephalitis response correlates with specific SNPs in the candidate genes.


On Dec 8, 2006, at 3:16 PM, Susie Stephens wrote:


Here's a reminder for Monday's BioRDF call.

Date of Call: Monday December 11, 2006
Time of Call: 11:00am Eastern Time
Dial-In #: +1.617.761.6200 (Cambridge, MA)
Participant Access Code: 246733 ("BIORDF")
IRC Channel: irc.w3.org port 6665 channel #BioRDF
Duration: ~1 hour

Agenda
Matthias Samwald and Alan Ruttenberg will be providing task updates.
Bill Bug, Elizabeth Wu and Scott Marshall will be discussing the scientific queries that they have been researching.

Kind regards,

Susie




Bill Bug
Senior Research Analyst/Ontological Engineer

Laboratory for Bioimaging  & Anatomical Informatics
www.neuroterrain.org
Department of Neurobiology & Anatomy
Drexel University College of Medicine
2900 Queen Lane
Philadelphia, PA    19129
215 991 8430 (ph)
610 457 0443 (mobile)
215 843 9367 (fax)


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