Two pathways of exocytosis of cytoplasmic granule contents and target cell killing by cytokine-induced CD3+ CD56+ killer cells

Cytokine-induced killer (CIK) cells are non-major histocompatibility complex-restricted cytotoxic cells generated by incubation of peripheral blood lymphocytes with anti-CD3 monoclonal antibody (MoAb), interleukin-2 (IL-2), IL-1, and interferon-gamma. Cells with the greatest effector function in CIK cultures coexpress CD3 and CD56 surface molecules. CIK cell cytotoxicity can be blocked by MoAbs directed against the cell surface protein leukocyte function associated antigen-1 but not by anti-CD3 MoAbs. CIK cells undergo release of cytoplasmic cytotoxic granule contents to the extracellular space upon stimulation with anti-CD3 MoAbs or susceptible target cells. Maximal granule release was observed from the CD3+ CD56+ subset of effector cells. The cytoplasmic granule contents are lytic to target cells. Treatment of the effector cells with a cell-permeable analog of cyclic adenosine monophosphate (cAMP) inhibited anti-CD3 MoAb and target cell- induced degranulation and cytotoxicity of CIK cells. The immunosuppressive drugs cyclosporin (CsA) and FK506 inhibited anti-CD3- mediated degranulation, but did not affect cytotoxicity of CIK cells against tumor target cells. In addition, degranulation induced by target cells was unaffected by CsA and FK506. Our results indicate that two mechanisms of cytoplasmic granule release are operative in the CD3+ CD56+ killer cells; however, cytotoxicity proceeds through a cAMP- sensitive, CsA- and FK506-insensitive pathway triggered by yet-to-be- identified target cell surface molecules.     

Effects of rivastigmine on cognitive function in dementia with lewy bodies: a randomised placebo-controlled international study using the cognitive drug research computerised assessment system

This study was designed to assess the effects of rivastigmine (Exelon) on the cognitive functioning of patients suffering from dementia with Lewy bodies. This was a prospective, multi-centre, randomised, double-blind, placebo-controlled exploratory study conducted at sites in the UK, Spain and Italy. The treatment period was 20 weeks with a 3-week posttreatment follow-up. The primary outcome measures were the Cognitive Drug Research (CDR) computerised assessment system and the Neuropsychiatric Inventory. Testing was conducted prior to dosing and then again at weeks 12, 20 and 23. Analysis of the data from the 92 patients who completed the study identified a significant pattern of benefits of rivastigmine over placebo on the CDR system. These benefits were seen on tests of attention, working memory and episodic secondary memory. Taking attention for example, patients given placebo showed a significant deterioration from predosing scores at 12 and 20 weeks, whereas patients on rivastigmine performed significantly above their predosing levels. These effects were also large in magnitude, the decline under placebo at week 12 being 19%, while the improvement under rivastigmine was 23%. The clinical relevance of this 23% improvement was that it took the patients 33% towards being normal for their age on this assessment of attention. These benefits to cognitive function were accompanied by a significant improvement of the other primary outcome measure, the Neuropsychiatric Inventory. Three weeks after discontinuation of rivastigmine, most parameters of cognitive performance returned to predrug levels.     

Volumetric MRI study of the caudate nucleus in patients with dementia with Lewy bodies, Alzheimer's disease, and vascular dementia

OBJECTIVES: To determine whether parkinsonian symptoms in dementia with Lewy bodies (DLB) are associated with greater atrophy of the caudate nucleus in comparison with patients with Alzheimer's disease (AD) and vascular dementia (VaD). METHODS: T1weighted MR scans were acquired in elderly patients with DLB, AD, VaD, and healthy controls. Normalised volumetric measurements of the caudate nucleus were obtained and parkinsonian symptoms rated using Hoehn and Yahr staging. RESULTS: There were no significant differences in the volume of the caudate nucleus between patients with dementia. However, the left caudate volume was significantly reduced in AD and DLB compared with controls. Parkinsonian symptoms did not correlate with caudate nucleus volume. CONCLUSIONS: Parkinsonian symptoms in DLB may be more closely coupled to neurochemical rather than structural changes in the caudate nucleus, and volumetric MRI analysis of caudate nucleus does not discriminate between patients with DLB, AD, and VaD.     

Quantifying fluctuation in dementia with Lewy bodies, Alzheimer's disease, and vascular dementia

BACKGROUND: Case reports and clinical observations suggest that fluctuating cognition (FC) is common in the major dementias, particularly dementia with Lewy bodies (DLB), where it is one of three core clinical diagnostic features. OBJECTIVES: To examine the frequency, characteristics, and diagnostic utility of FC in dementia using clinical, attentional, and EEG markers. Method:- A total of 155 subjects (61 with AD, 37 with DLB, 22 with vascular dementia [VaD], 35 elderly controls) received clinical evaluation for FC using a semiquantified measure applied by experienced clinicians and 90-second cognitive choice reaction time (CRT) and vigilance reaction time (VIGRT) trials. Forty subjects also received an evaluation of mean EEG frequency across 90 seconds. RESULTS: Patients with DLB had a greater prevalence and severity of FC than did patients with AD or VaD rated using clinical, attentional, and EEG measures. The 90-second cognitive and EEG trials demonstrated that FC occurs on a second-to-second basis in patients with DLB. Patients with VaD had a higher prevalence of FC than did those with AD, although the profile of FC was different from that expressed by DLB cases. Optimal cutoff values on the clinical scale achieved good discrimination between the dementia groups (sensitivity 81%, specificity 92%, DLB versus AD; sensitivity 81%, specificity 82%, DLB versus VaD; sensitivity 64%, specificity 77%, VaD versus AD). CONCLUSION: Standardized assessment methods demonstrate that FC is significantly more common and severe in DLB than in other major dementias. The periodicity of FC is different in DLB and VaD cases, with important implications for the underlying causal mechanisms and for differential diagnosis.     

Dementia with lewy bodies: findings from an international multicentre study

OBJECTIVES: To describe the baseline demographic, neuropsychiatric and neurological data of a large selected clinical sample of patients with dementia with Lewy Bodies (DLB) from an international multicentre trial with rivastigmine. To examine the usefulness of the Consensus Criteria for the diagnosis of DLB in different countries. METHODS: Seventeen centres from Spain, the UK and Italy recruited patients diagnosed clinically as probable DLB according to recent Consensus Criteria (McKeith et al., 1996). A standard clinical protocol including inclusion/exclusion criteria, collection of demographic and medical data, cognitive (Mini Mental State Examination: MMSE), motor (Unified Parkinson's Disease Rating Scale: UPDRS) and neuropsychiatric (Neuropsychiatric Inventory: NPI) examinations, was applied after obtaining informed consent. Data were summarised and compared across countries with uni- and multivariate analyses. RESULTS: One hundred and twenty patients were recruited: 56.7% males, mean (SD) age 73.9 (6.4) years, range 57 - 87 years. Sixty percent fulfilled all three core diagnostic features of DLB, and 40% only two ('parkinsonism' 92.4%, 'cognitive fluctuations' 89.1%, 'visual hallucinations' 77.3%). 'Systematised delusions' (46%) and 'repeated falls' (42%) were the most frequent supportive diagnostic features. There were no differences across countries in demographic, diagnostic or clinical features. Patients showed a wide range of psychopathology which was weakly correlated with cognitive impairment. Some mild extrapyramidal signs (EPS) were observed in most patients. CONCLUSIONS: The Consensus Criteria for DLB can be consistently applied across many different sites for multicentre studies. 'Parkinsonism' and 'cognitive fluctuations' as core features and 'systematised delusions' and 'repeated falls' as supportive features are the most frequent diagnostic clues. Neuropsychiatric disturbances, in particular apathy, delusions, hallucinations and anxiety, and mild symmetric EPS are frequent in DLB and are only related weakly to cognitive impairment.     

Interval between insulin injection and breakfast in diabetes

The relationship between the insulin-breakfast interval, postprandial increase in blood glucose, and glycaemic control was studied in 58 children with diabetes. Patients recorded insulin-breakfast intervals in a home diary over a seven day period, and during a 24 hour period at the weekend provided eight serial capillary dried blood spots for glucose analysis. The highest mean blood glucose value occurred two hours after breakfast and showed a significant correlation with fructosamine concentrations. Weekend insulin-breakfast intervals ranged from 2-30 minutes, with 70% reporting intervals of less than 15 minutes. There was a significant correlation between the weekend insulin-breakfast interval and the after breakfast increase in blood glucose with a mean increment of 0.4 mmol/l in the 30 minute group and 7.2 mmol/l in the 2 minute group. Over the whole study period, children with mean insulin-breakfast intervals of two to 12 minutes had a mean fructosamine concentration of 376 mumol/l compared with 341 mumol/l in those with intervals of 15-35 minutes. This study has shown that the interval between insulin injection and breakfast significantly influences the morning postprandial rise in blood glucose and consequently short term glycaemic control. It is therefore important that patients are encouraged to leave an interval of about 30 minutes between insulin injection and breakfast.     

Neuroleptics are associated with more severe tangle pathology in dementia with Lewy bodies

BACKGROUND: Neuroleptics are only modestly effective in dementia and associated with a range of adverse effects including cognitive decline. Effects of the drugs on molecular pathology in brain tissue from people with dementia have not been investigated. OBJECTIVES: To compare the severity of Alzheimer type pathology in matched groups of people with dementia with Lewy bodies (DLB), treated and not treated with neuroleptics. METHODS: The relationship between neuroleptics and Alzheimer-type pathology was determined in 40 (17 neuroleptic treated, 23 neuroleptic free, matched for age, disease duration and psychosis) clinically prospectively studied, autopsy diagnosed DLB patients. RESULTS: In regression analyses, taking neuroleptics was significantly associated with increased neurofibrillary tangles but not amyloid plaques in cortical areas examined. The patient characteristics and the frequencies of key psychiatric symptoms were similar in the patients taking and not taking neuroleptics. CONCLUSION: Although patients were not randomized and the results which are observed need to be interpreted cautiously, if substantiated, this is an important finding with major implications for the pharmacological management of DLB patients and highlights the need to determine the impact of neuroleptics upon tangle pathology in AD.     

Longitudinal study of cerebral blood flow SPECT in Parkinson's disease with dementia, and dementia with Lewy bodies

BACKGROUND: People with Parkinson's disease (PD) have an increased risk of developing dementia (PDD), which often has clinical features similar to dementia with Lewy bodies (DLB). Whilst perfusion studies have shown parieto-occipital hypoperfusion in DLB and PDD relative to controls, there have not been any longitudinal studies of perfusion changes in PDD and DLB. METHODS: In this study, we measured brain perfusion using Tc99m HMPAO SPECT over one year in 17 PDD, 18 DLB and 34 healthy subjects. We used SPM99 to compare perfusion changes in the two dementia groups against the control group. RESULTS: We did not see any reductions in perfusion in either of the dementia groups. However, in the DLB, but not PDD group, there was a significant increase in putamen perfusion relative to controls over the year. In both DLB and PDD groups, there was a correlation between striatal perfusion increase over the year, and worsening of parkinsonism. Perfusion changes were not secondary to changes in antiparkinsonian medication. CONCLUSION: The increase in striatal perfusion may be a compensatory change related to decreasing striatal dopaminergic input from the substantia nigra in PDD and DLB, consistent with the increased predominance of rigidity over tremor symptoms in these groups compared with non-demented PD.