Disruption of serine/threonine protein phosphatase 5 (PP5:PPP5c) in mice reveals a novel role for PP5 in the regulation of ultraviolet light-induced phosphorylation of serine/threonine protein kinase Chk1 (CHEK1).

PP5 is a ubiquitously expressed Ser/Thr protein phosphatase. High levels of PP5 have been observed in human cancers, and constitutive PP5 overexpression aids tumor progression in mouse models of tumor development. However, PP5 is highly conserved among species, and the roles of PP5 in normal tissues are not clear.

Neuropsychological test scores and clinical response to neuroleptic drugs in schizophrenic patients.

Schizophrenic patients who showed greater neuropsychological deficits on the Luria-Nebraska Pathognomonic subscale (PATH) and Trail-Making Test showed less improvement during treatment with neuroleptic drugs than patients with lower scores on these neuropsychological tests. Other neuropsychological test scores we used were not consistently related to the patients' degree of clinical improvement during neuroleptic treatment. Only a few patients evidenced severe scores on either the PATH or TM tests, suggesting that more subtle neuropsychological deficits may identify a subgroup of schizophrenics who will show a relatively poor response to treatment with standard neuroleptic drugs.

Cortical atrophy and white matter density in the brains of schizophrenics and clinical response to neuroleptics.

The relationship between clinical response to neuroleptics and brain morphology as revealed by CT scans was evaluated in a sample of 39 patients with schizophrenia and schizoaffective psychosis. Four measures of brain morphology previously shown to differ between schizophrenics and patients with headaches - white matter density, asymmetry in brain white matter density, sulcal width and global cortical atrophy - did not correlate with clinical improvement after 3 weeks treatment with constant doses of neuroleptics. These brain morphology measures also did not correlate with baseline psychopathology scores.