The subjects will also have a blood test to measure the level of Vit. B12. (The sample will undergo centrifuge within the next few hours and the serum will be kept frozen until the test is done.) Since in our retrospective study (to be published) we did not find any difference in the result of treatment between people with patients having high and low levels of Vit. B12 in their blood, the level of Vit. B12 was not included as a criterion for inclusion or exclusion in the study.