An in vitro system to study drug sensitivity of Mycobacterium leprae using infected human tissue

A reliable screening technique for assessing the sensitivity of Mycobacterium leprae to drugs has been developed. The method is based on the susceptibility or otherwise of M. leprae- infected tissues from lepromatous leprosy patients to the action of diaminodiphenyl sulphone (dapsone) or rifampicin on the incorporation of [14C]-acetate into lipids. The extent of inhibition or lack of inhibition correlated very well with the drug sensitivity or resistance of the bacteria isolated from the patients to the above drugs. A similar trend was observed when the incorporation into individual fractions of neutral lipids was measured. There was no incorporation by heat-killed tissues. This method correlates well with the 3,4-dihydroxyphenylalanine uptake studies

Increased hippocampal CA1 cerebral blood volume in schizophrenia

Hippocampal hyperactivity has been proposed as a biomarker in schizophrenia. However, there is a debate whether the CA1 or the CA2/3 subfield is selectively affected. We studied 15 schizophrenia patients and 15 matched healthy control subjects with 3T steady state, gadolinium-enhanced, absolute cerebral blood volume (CBV) maps, perpendicular to the long axis of the hippocampus. The subfields of the hippocampal formation (subiculum, CA1, CA2/3, and hilus/dentate gyrus) were manually segmented to establish CBV values. Comparing anterior CA1 and CA2/3 CBV between patients and controls revealed a significant subfield-by-diagnosis interaction. This interaction was due to the combined effect of a trend of increased CA1 CBV (p = .06) and non-significantly decreased CA2/3 CBV (p = 0.14) in patients relative to healthy controls. These results support the emerging hypothesis of increased hippocampal activity as a biomarker of schizophrenia and highlight the importance of subfield-level investigations