Further validation of the Motivation for Traumatic Brain Injury Rehabilitation Questionnaire (MOT-Q) in patients with acquired brain injury

The Motivation for Traumatic Brain Injury Rehabilitation Questionnaire (MOT-Q) evaluates motivation for rehabilitation in four subscales: Interest in rehabilitation, Lack of anger, Lack of denial, and Reliance on professional help. The objective of this study was to further validate the MOT-Q in 122 inpatients and 92 outpatients with acquired brain injury (ABI). The main measures were motivation for rehabilitation (MOT-Q), self-awareness (Patient Competency Rating Scale), and treatment motivation (Visual Analogue Scale). The MOT-Q showed adequate feasibility in terms of few items with missing responses and few undecided responses. We found no floor or ceiling effects, and significant item-total MOT-Q correlations for 29 of 31 items. Internal consistency was good for the MOT-Q total and acceptable to good for the subscales. The MOT-Q scores were significantly intercorrelated except for the subscales Lack of denial and Reliance on professional help in the inpatient group. The MOT-Q total and subscales were significantly associated with treatment motivation. The Lack of denial subscale showed no significant association with treatment motivation and no to moderate significant associations with self-awareness. In conclusion, the overall MOT-Q is a valid instrument to assess motivation for rehabilitation in patients with ABI. Further research is needed to examine the validity of the subscales.     

Glucose 6-phosphate dehydrogenase mutations causing enzyme deficiency in a model of the tertiary structure of the human enzyme

Human glucose 6-phosphate dehydrogenase (G6PD) has a particularly large number of variants resulting from point mutations; some 60 mutations have been sequenced to date. Many variants, some polymorphic, are associated with enzyme deficiency. Certain variants have severe clinical manifestations; for such variants, the mutant enzyme almost always displays a reduced thermal stability. A homology model of human G6PD has been built, based on the three-dimensional structure of the enzyme from Leuconostoc mesenteroides. The model has suggested structural reasons for the diminished enzyme stability and hence for deficiency. It has shown that a cluster of mutations in exon 10, resulting in severe clinical symptoms, occurs at or near the dimer interface of the enzyme, that the eight-residue deletion in the variant Nara is at a surface loop, and that the two mutations in the A- variant are close together in the three-dimensional structure.     

Effects of fresh-frozen plasma and its cryosupernatant fraction on von Willebrand factor multimeric forms in chronic relapsing thrombotic thrombocytopenic purpura

Remission plasma samples of some patients with chronic relapsing thrombotic thrombocytopenic purpura (TTP) contain unusually large von Willebrand factor (vWF) multimers similar to those produced by normal human endothelial cells in culture. The infusion of the cryosupernatant fraction of normal plasma is as effective as normal fresh-frozen plasma (FFP) in the treatment or prevention of TTP episodes in patients with the chronic relapsing form of TTP. Three patients with chronic relapsing TTP during remission have unusually large vWF multimers present in their plasma. Two of the patients were transfused once with FFP, one of the two received cryosupernatant on three occasions, and the third patient was studied before and immediately after plasma exchange. Unusually large vWF multimers decreased or disappeared from patient plasma samples within 1/2 to 1 1/2 hours following the transfusion of FFP (on two occasions) or cryosupernatant (on two of three occasions), and immediately after plasma exchange (on one occasion). The patient who received cryosupernatant was studied serially after the infusions. Unusually large vWF multimers returned to her plasma within ten to 24 hours and persisted thereafter. Unusually large vWF multimers did not disappear from patient remission plasma samples, or from the culture medium removed from normal human endothelial cells, when these fluids were incubated in vitro with either normal FFP or cryosupernatant. We conclude that an activity in FFP, and its cryosupernatant fraction, promoted the rapid in vivo disappearance of unusually large vWF multimers from the plasma of two patients with chronic relapsing TTP in remission, and plasma exchange reversed the abnormality in a third patient who was in partial remission. Neither FFP nor cryosupernatant directly converted unusually large multimers to smaller vWF forms in vitro in the fluid phase. These results indicate that an activity in the cryosupernatant fraction of normal plasma is involved in vivo in controlling the metabolism of unusually large vWF multimers, and that this process is defective in some chronic relapsing TTP patients.