Formation of cytosine arabinoside-5'-triphosphate in different cultured lymphoblastic leukaemic cells with reference to their drug sensitivity.

The accumulation of intracellular cytosine arabinoside-5'-triphosphate (Ara-CTP) is determined in five lymphoblastic cell lines: Molt 4, H9 and three newly established cell lines from paediatric patients, KFB-1, KFB-2, KFT-1. The cell lines KFB-1 and KFB-2 are B-lymphoblastic (B-ALL), the others are T-lymphoblastic leukaemic cells (T-ALL). The Ara-CTP levels were compared with the sensitivity of the cells to Ara-C. The cells were incubated at different concentrations (100 nM-100 microM) of Ara-C for 4 h or incubated for variable times (30 min-11 h) at 0.1, 1 and 10 microM Ara-C to form Ara-CTP. The Ara-CTP-concentrations were measured by high pressure liquid chromatography (HPLC). To determine the sensitivity of the cells to Ara-C, the MTT colorimetric-assay was used. The studies indicate that different B- and T-lymphoblastic leukaemia cell lines accumulate Ara-CTP to a markedly different extent. Ara-CTP plateau levels and sensitivity of the cells to Ara-C correlated well in four of the five cells lines studied.

Spatiotemporal gait patterns during over ground locomotion in major depression compared with healthy controls.

Alterations of locomotion are frequent, observable features of patients suffering from depression and have been investigated in these patients by actigraphy, cinematography and ground reaction forces. However, spatiotemporal parameters and neurophysiological mechanisms of gait have not yet been studied in depth in depression. The relationship between spatial and temporal parameters may yield insight into the pathophysiology of altered movements in depression. Therefore, gait patterns were quantitatively assessed and analysed in depressed subjects (n=16) and compared to matched healthy controls. Spatiotemporal gait parameters were measured during over ground walking at self-selected walking speed on a walkway previously validated in healthy subjects and used for orthopaedic and neurological patients. Compared to controls, depressed patients showed significantly lower gait velocity (p<0.001), reduced stride length (p<0.005), double limb support (p<0.005) and cycle duration (p<0.005). There was a significant correlation between cadence and gait velocity in depressed patients (r=0.51, p<0.05), but not in healthy controls (r=0.11, p>0.05). In patients with major depression, reduced gait velocity was associated with stride hypometria and increased cycle duration. Velocity was associated with cadence in depressed patients but not in healthy controls. The results may indicate possible deficiencies in the motor control system in depression. These first results about alterations of spatiotemporal gait patterns in depression warrant further longitudinal and experimental studies.

[Motor behavior in depression: applications and limitations of actigraphic analyses]. / Aktivität und Depression--Möglichkeiten und Grenzen aktigraphischer Verhaltensanalysen.

OBJECTIVE: Alterations of motor behavior in depression play a key role in psychosocial activities and interpersonal communication and are relevant for differential diagnosis and treatment. Functions and application of actigraphy and empirical findings in depression will be summarised and discussed. METHODS: The current knowledge retrieved from information of manufacturers, Medline, PsycLIT, and PSYNDEX regarding features of actigraphic equipment and clinical aspects of gross motor analysis in depression was examined. RESULTS: Actigraphy is a practical method to monitor and quantify gross motor activity, but setting variables including sensitivity or epoch length vary among commercially available instruments. Measures of motor activity in depressed patients are used for diagnosis, evaluation of sleep, and prediction of treatment response. CONCLUSIONS: Measurements of motor behavior by actigraphy can be used in depression for diagnostic procedures and treatment evaluation. The role of actigraphic setting variables needs further clarification. Actigraphy may be used for behavioral analysis including individual regulation of motor activity as an objective parameter for evaluation of depression and other psychiatric disorders.