WorkItemCollection queryResults = workItemStore.Query(
"Select [State], [Title], [Work Item Type], [Changed Date], [Changed by], [System.ChangedBy], " +
"[Microsoft.VSTS.TCM.ReproSteps], [Microsoft.VSTS.Common.Severity],  [Microsoft.VSTS.Common.Priority] " +
"From WorkItems " +
"Where [Work Item Type] = 'Bug' AND " +
"[System.TeamProject] = '" + _codProyecto + "' ");

int numWI = queryResults.Count;
WorkItem[] arrayWI = new WorkItem[numWI];
arrayWI = queryResults.Cast<WorkItem>().ToArray();
IList<WorkItem> listWI = Array.AsReadOnly(arrayWI);

Bug bicho;
List<Bug> lob = new List<Bug>();
Parallel.For(0, numWI, j =>
        {
            WorkItem aWI = listWI[j];
            bicho = new Bug();
            bicho.Id = aWI.Id;
            bicho.ImageIndex = 0;
            bicho.Title = aWI.Title;
            bicho.State = aWI.State;.
});