Influence of action and expectation on visual control of posture

Previous studies have shown that human subjects presented with a moving visual environment initiate a postural re-adjustment in the direction of motion. The present study investigated how active control or expectation of the displacement of a visual scene affects this postural response. Center of foot pressure (COP) and head displacement were recorded using a sway platform and a tracking system, respectively. The subjects faced a visual scene (1 x 1 m, at a distance of 45 cm) which moved transiently (with a velocity of 1 cm/s) in a direction parallel to the interaural axis. When the displacement of the visual scene was under the active control of the subjects, visually induced body sway was strongly inhibited, in comparison with the response to unexpected stimuli. Prior knowledge of the characteristics of the forthcoming displacement was sufficient, in most subjects, to reduce postural re-adjustment, even when subjects did not exert active control. Finally, the visually induced postural response was strongly reduced even when subjects only triggered the stimulus, without any knowledge about the direction of motion. In conclusion, it appears that although vision is of primary importance in the control of postural orientation, high level processes such as expectation can modulate its impact by providing cues as to whether forthcoming visual flow is the consequence of self-motion or object-motion.     

Inhibition of metalloproteinases enhances the internalization of anti-CD30 antibody Ki-3 and the cytotoxic activity of Ki-3 immunotoxin

CD30 is selectively expressed on the tumor cells of a variety of malignant disorders of the immune system and can therefore be used as a target for an anti-CD30 antibody-based immunotherapy. However, CD30 is cleaved at the cell surface by tumor necrosis factor-alpha converting enzyme (TACE). This metalloproteinase releases the soluble ectodomain of CD30 (sCD30), which is able to neutralize immunotherapeutic agents before these reach their target cells. Such constitutive CD30 cleavage is enhanced after binding of most anti-CD30 antibodies, leading to a downregulation of CD30 and an increase of sCD30 in the cell environment. Here, we demonstrate that CD30 shedding from the cell line Karpas 299 could effectively be blocked by the hydroxamic acid-based metalloproteinase inhibitors BB-3644 (IC50 = 180 nM), BB-2116 (IC50 = 230 nM), BB-94 (batimastat, IC50 = 230 nM) and BB-2516 (marimastat, IC50 = 1 microM). This inhibition reduced the concentration of sCD30 in the cell environment to the background level, prolonged the persistence of the anti-CD30 antibody Ki-3 on Karpas 299 cells and favored its internalization. Moreover, a nontoxic concentration of the inhibitor BB-3644 significantly increased the cytotoxic activity of the anti-CD30 ricin A-chain immunotoxin Ki-3.dgA towards the CD30(+) Hodgkin-derived cell line L540. Hence, the metalloproteinase inhibitor BB-3644 may be a promising compound to improve the immunotherapy of CD30(+) malignancies.     

Zytophotometrische Untersuchungen an Rezidivgliomen Korrelation der DNA-Parameter mit dem WHO-Grad, dem Proliferationsindex und der Länge der rezidivfreien Intervalle

DNA-cytophotometry is one of the methods that may contribute to a more precise evaluation of the biological behaviour of tumours in addition to the WHO-classification. In this study 121 tumour specimens of 50 patients suffering from gliomas with one or up to three recurrencies were investigated. In all cases the histological type and WHO-grade and the Ki-67/MIB1 labeling index were determined. DNA cytophotometry was performed after single cell preparation on Feulgen-stained preparations, and the following parameters were calculated: stemline ploidy, 5c-exceeding rate, and 2c-deviation index. Statistical evaluation revealed a highly significant correlation between recurrence-free interval and WHO-grade only. The DNA parameters, however, furnished additional information about increasing genetic instability in the majority of the recurrencies independently of changes in the WHO-grade. They thus seem to be useful as additional parameters for the determination of glioma progression.     

Relation of neurological soft signs to nonverbal memory performance in obsessive-compulsive disorder

Few studies have examined the relation between neurological soft signs (NSS) and neuropsychological performance in Obsessive-Compulsive Disorder (OCD). Thirty outpatients with primary OCD and 30 matched normal controls were administered the Cambridge Neurological Inventory and the Rey-Osterrieth Complex Figure Test (RCFT). A series of multiple regression models tested the relationship between NSS and performance on the RCFT. Patients presented significantly more neurological soft signs than controls on both sides of the body, and were impaired on the free recall and organization scores of the RCFT. Nonverbal memory deficits in OCD were predicted independently by organizational strategies during the copy condition of the RCFT, and neurological soft signs. There might be at least two variables independently mediating nonverbal memory deficits in OCD: (1) a cognitive organization and planning component, and (2) a complex motor regulatory component.     

Meeting information needs to facilitate decision making: report cards for people with disabilities.

BACKGROUND: Several states within the United States offer low-income adults with disabilities a choice of health plans. No states issue comparative 'report cards' specifically for adults with disabilities. OBJECTIVE: To explore conceptualizations of quality, information needs, and report card preferences from the perspective of people with disabilities. RESEARCH DESIGN: Eight focus group interviews were conducted in 2003. Existing report cards for California, Maryland, Michigan and Texas were shared for feedback. SUBJECTS: 34 women and 15 men with various behavioural, physical or sensory disabilities in Oregon, California, Virginia, Maryland and the District of Columbia. RESULTS: Quality was mostly defined in terms of choice and disability sensitivity of service providers. Respondents identified various obstacles to receiving appropriate health plan and service information. All beneficiaries were keenly interested in the comparative health plan report cards, but did not think the report cards provided enough pertinent information, especially with regard to provider ratings, accessibility, disability competence and reasons for participating in the Medicaid program. CONCLUSIONS: Existing comparative report cards omit several major content domains important to people with disabilities. Organizations providing decision support to people with disabilities should cultivate novel avenues for distribution, such as food banks, libraries and places of worship.     

Changes in horizontal oculomotor behaviour coincide with a shift in visual motion perception

During full-field rotation of the visual field, subjects commonly experience an initial perception of object-motion which 'switches' to a perception of self-motion. We studied the characteristics of the horizontal optokinetic nystagmus responses evoked by a moving visual stimulus in these two perceptual states over a range of stimulus velocities. During self-motion perception mean eye position was found to shift more in the direction of the newly appearing stimulus elements with a slight reduction in slow phase gain in comparison to the nystagmus evoked during object-motion perception. The results may reflect a modified strategy of spatial attention with increased emphasis on anticipatory eye movements during visually induced self-motion perception.     

Reliability of Medicaid Claims Files for Use in Psychiatric Diagnoses and Service Delivery

To investigate the reliability of Medicaid claims data for use in research, clinical decision-making, and policy, medical records were abstracted of 105 inpatient stays on the psychiatric service of a large general hospital. Primary and secondary diagnoses and outpatient specialty mental health services after hospitalization were compared between Medicaid claims data and medical record information. Primary and secondary diagnoses were reliable, but claims data failed to capture several types of outpatient services. This suggests strategies to use claims files more appropriately.