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Biomedical subjects

B W van Oosten

Publications and source records attributed to B W van Oosten.

14 recordsLinked to original sources
PubMed1999

Development of hypointense lesions on T1-weighted spin-echo magnetic resonance images in multiple sclerosis: relation to inflammatory activity.

OBJECTIVE: To evaluate whether degree of inflammatory activity in multiple sclerosis, expressed by frequency of gadolinium enhancement, has prognostic value for development of hypointense lesions on T1-weighted spin-echo magnetic resonance images, a putative marker of tissue destruction. DESIGN: Cohort design with long-term follow-up. Thirty-eight patients with multiple sclerosis who in the past had been monitored with monthly gadolinium-enhanced magnetic resonance imaging for a median period of 10 months (range, 6-12 months) were reexamined after a median period of 40.5 months (range, 33-80 months). SETTING: Magnetic Resonance Center for Multiple Sclerosis Research, Amsterdam, the Netherlands, referral center. MAIN OUTCOME MEASURES: The new enhancing lesion rate (median number of gadolinium-enhancing lesions per monthly scan) during initial monthly follow-up; hypointense T1 and hyperintense T2 lesion load at first and last visit. RESULTS: The number of enhancing lesions on entry scan correlated with the new enhancing lesions rate (r = 0.64; P<.001, Spearman rank correlation coefficient). The new enhancing lesion rate correlated with yearly increase in T1 (r = 0.42; P<.01, Spearman rank correlation coefficient) and T2 (r = 0.47; P<.01, Spearman rank correlation coefficient) lesion load. Initial T1 lesion load correlated more strongly with yearly increase in T1 lesion load (r = 0.68; P<.01, Spearman rank correlation coefficient). CONCLUSIONS: Degree of inflammatory activity only partially predicted increase in T1 (and T2) lesion load at long-term follow-up. Initial T1 lesion load strongly contributed to subsequent increase in hypointense T1 lesion load, suggesting that there is a subpopulation of patients with multiple sclerosis who are prone to develop destructive lesions.

Adult↗
PubMed1999

Decreased interleukin-10 and increased interleukin-12p40 mRNA are associated with disease activity and characterize different disease stages in multiple sclerosis.

It has been shown that proinflammatory and antiinflammatory cytokines correlate with disease activity in multiple sclerosis (MS). To establish whether such correlations depend on the disease stage, we assessed in a longitudinal fashion the expression of interleukin (IL)-12 (p40 and p35), tumor necrosis factor-alpha, interferon-gamma, and IL-10 mRNA by competitive polymerase chain reaction in unstimulated peripheral blood mononuclear cells of relapsing-remitting (RR) and secondary progressive (SP) MS patients, in relation to monthly clinical and magnetic resonance imaging monitoring. MS patients had increased levels of IL-12p40 and decreased levels of IL-10 mRNA compared with controls; this difference was most pronounced in SP patients. Both RR and SP patients had increased levels of IL-12p40 mRNA compared with controls during the development of active lesions. Moreover, in RR MS an increase was found before relapse. IL-12p35 mRNA was decreased in both groups, and in relation to disease activity it showed a pattern different from IL-12p40 mRNA. In RR MS, IL-10 mRNA was low 4 weeks before magnetic resonance imaging activity and 6 weeks before relapse; a significant increase to normal levels was noted when active lesions became apparent. In contrast, SP patients showed low IL-10 mRNA levels constitutively, suggesting that IL-10 plays an important role in the control of disease progression.

Adult↗
PubMed1998

Increased production of tumor necrosis factor alpha, and not of interferon gamma, preceding disease activity in patients with multiple sclerosis.

OBJECTIVE: To study whether tumor necrosis factor (TNF) alpha or interferon (IFN) gamma production by stimulated white blood cells precedes or accompanies clinical and magnetic resonance imaging signs of disease activity in patients with multiple sclerosis. DESIGN: Prospective study with a follow-up of 9 months. SETTING: Patients visiting an outpatient university clinic. PATIENTS: The 30 Amsterdam-based patients (28 completing all evaluations) participating in a multicenter, randomized, placebo-controlled, double-blind trial of a chimeric anti-CD4 antibody in the treatment of active relapsing-remitting and secondary progressive multiple sclerosis. Patients in both treatment arms were included, because for these patients anti-CD4 treatment in this study did not affect TNF-alpha and IFN-gamma production and did not reduce signs of disease activity on magnetic resonance imaging. MAIN OUTCOME MEASURE: Distribution of classes of TNF-alpha and IFN-gamma production (expressed as z scores) in patients with or without clinical or magnetic resonance imaging signs of disease activity. RESULTS: One month preceding exacerbations of multiple sclerosis, there was a shift toward higher z scores of TNF-alpha production (P<.05), but not of IFN-gamma production. There was no statistically significant relationship between IFN-gamma and TNF-alpha production and magnetic resonance imaging markers of multiple sclerosis activity. CONCLUSION: The production of TNF-alpha, and not of IFN-gamma, is significantly higher in patients with multiple sclerosis before exacerbations than in patients with stable disease. Although present, this relationship is too weak to use TNF-alpha production as a surrogate marker of disease activity in multiple sclerosis.

Adult↗
PubMed1998

Choosing drug therapy for multiple sclerosis. An update.

Multiple sclerosis (MS) is an immunologically mediated disorder in which inflammation and demyelination of the central nervous system white matter are prominent features, resulting in various neurological signs and symptoms. In most patients, the course of the disease is initially characterised by relapses and remissions. In patients with chronic disease there is a tendency towards a gradually progressive disease course. MS relapses can best be treated with a course of high dose intravenous methylprednisolone. In ambulatory patients with relapsing remitting MS, partial prevention of relapses can be achieved by the use of interferon-beta-1a or -1b, whereas there is (as yet less convincing) evidence that glatiramer acetate (copolymer-1) might also be effective. At this time, there is no proof that these drugs are effective in patients with progressive MS, although trial results are expected to be available soon. In patients with rapidly progressive disease, it might be worth considering the effect of methotrexate. Future treatment options include new strategies to interfere with disease-relevant, specific or nonspecific immune mechanisms as well as drugs that might promote remyelination. In spite of the advances that have been made over the past few years, symptomatic treatment, including a multidisciplinary rehabilitation approach, remains the mainstay of treatment of the majority of MS patients.

Anti-Inflammatory Agents↗
PubMed1997

Treatment with depleting CD4 monoclonal antibody results in a preferential loss of circulating naive T cells but does not affect IFN-gamma secreting TH1 cells in humans.

CD4(pos) TH1 T cells are considered to play a central role in a number of human autoimmune diseases such as rheumatoid arthritis (RA) and multiple sclerosis. Experimental treatment protocols aimed at selectively eliminating CD4(pos) T cells thus far have yielded disappointing clinical results. Here we analyzed phenotype and function of circulating T cells in multiple sclerosis patients treated with the chimeric CD4 mAb cM-T412 in a randomized, double-blind, placebo-controlled, magnetic resonance imaging-monitored phase II trial. Treatment resulted in a long-lasting depletion of CD4(pos) T cells but did not affect CD8(pos) T cell numbers. Analysis of CD4(pos) subpopulations showed that unprimed, CD45RA(pos)/R0(neg) lymphocytes were approximately three times more sensitive to the mAb than primed, CD45RA(neg)/R0(pos) T cells. Notably, within the CD45RA(pos) subset, T cells with phenotypic evidence of prior activation, i.e., expressing Fas, were relatively insensitive to cM-T412, compared with Fas(neg) cells. Remarkably, while a decrease in the number of IL-4-producing T helper 2 (TH2)-type cells in the anti-CD4 treated group was observed, numbers of IFN-gamma-producing T helper 1 (TH1)-type cells remained stable, resulting in a significant increase in the TH1/TH2 ratio. Our data show that treatment with depleting CD4 mAb does not eliminate the cells most strongly involved in the disease process, i.e., primed, IFN-gamma-producing TH1-type cells, and may therefore give an explanation for the lack of beneficial clinical effects of depleting CD4 mAb in human chronic autoimmune disease.

Adult↗
PubMed1997

TNF-alpha promoter polymorphisms, production and susceptibility to multiple sclerosis in different groups of patients.

TNF-alpha production in whole blood cultures upon stimulation with LPS was determined in 179 individuals from 61 families in order to characterise the magnitude of inherited differences in TNF-alpha production. The three families characterised by highest TNF production showed 7.1 +/- 0.3 ng TNF/ml upon culture with 10 ng LPS and 10.2 +/- 0.2 ng TNF/ml upon culture with 1000 ng LPS. in contrast to the three families characterised by the lowest TNF production that showed a production of 1.6 +/- 0.1 ng TNF upon culture with 10 ng and 2.5 +/- 0.2 ng/ml upon culture with 1000 ng LPS/ml. This difference could not be attributed to the promoter polymorphisms -308 G to A. -238 G to A or -376 G to A, although the -238 GA donors produced 2.1 +/- 0.9 ng TNF upon culture with 10 ng endotoxin compared to 3.2 +/- 2.2 ng TNF for the -238 GG donors. In line with these results the frequency of the -238 GG genotype was increased in hospitalized MS patients in a nursing home (100% 238GG, n = 57) compared to MS patients in an outpatient's clinic (94% 238GG, n = 98) or Dutch controls (90% 238GG, n = 180). These results suggest that the -238 GG genotype is differently distributed in hospitalized MS patients in a nursing home.

Disease Susceptibility↗
PubMed1997

Treatment of multiple sclerosis with the monoclonal anti-CD4 antibody cM-T412: results of a randomized, double-blind, placebo-controlled, MR-monitored phase II trial.

We report the results of a randomized, double-blind, placebo-controlled exploratory trial of the chimeric monoclonal anti-CD4 antibody cM-T412 in 71 patients suffering from active relapsing-remitting and secondary progressive multiple sclerosis. Infusion of the antibody produced frequent but usually minor side effects and resulted in a long-lasting reduction of circulating CD4-positive T cells. There was no significant effect on the primary measure of efficacy, the number of active lesions on monthly gadolinium-enhanced MRI over 9 months. Further statistical evaluation provided evidence that the degree of depletion of CD4-positive cells was important with regard to treatment efficacy; using CD4 counts as a covariate there was a statistically significant effect on the number of active lesions over 18 months (p = 0.04). There was a statistically significant reduction of 41% in the number of clinical relapses (a secondary efficacy parameter) after 9 months (p = 0.02), which was still present after 18 months, but this finding may be partly due to physician unblinding. Other secondary efficacy parameters (Expanded Disability Status Scale progression, number of courses of methylprednisolone) were not influenced by anti-CD4 treatment. We conclude that intravenous treatment with the monoclonal antibody cM-T412 in the dosage we used results in a substantial and sustained reduction of the number of circulating CD4-positive cells, but is not able to reduce MS activity as measured by monthly gadolinium-enhanced MRI, and is therefore unlikely to have a beneficial effect on the clinical disease course. We found preliminary evidence suggesting that more aggressive depletion of CD4-positive cells might lead to a more substantial reduction in MRI activity.

Adult↗
PubMed1996

[Problems in weaning from artificial ventilation: 'motor neuron disease'].

Three patients, two men aged 71 and one aged 73 years, were given artificial respiration because of acute respiratory failure. Subsequently they could not be weaned from artificial respiration, due to causes that were not immediately clear. It was ultimately found that the patients suffered from 'motor neuron disease', in two of them due to progressive spinal muscular atrophy, while the third, apart from loss of anterior horn motor cells, also had thoracic hydromelia. The patients died after termination of the artificial respiration.

Aged↗
PubMed1996

A pilot study investigating the effects of orally administered pentoxifylline on selected immune variables in patients with multiple sclerosis.

Multiple sclerosis is probably mainly mediated by T-helper 1 (TH1)-lymphocytes. TH1-function can be down-regulated in vitro and in animal experiments by pentoxifylline. Therefore, we included 20 multiple sclerosis patients in an open label pilot trial of pentoxifylline. Outcome parameter was the effect of treatment on levels of various cytokines and adhesion molecules in cerebrospinal fluid and serum, on production of TH1- and TH2-cytokines using cell stimulation assays, as well as on measures of T-cell activation and proliferation. Kurtzke's EDSS was a secondary efficacy parameter. A convincing and consistent effect of pentoxifylline could not be demonstrated.

Administration, Oral↗
PubMed1996

A phase II trial of anti-CD4 antibodies in the treatment of multiple sclerosis.

In multiple sclerosis (MS) myelin damage is the result of a chronic inflammatory process mediated by CD4 positive T helper/effector cells. In experimental allergic encephalomyelitis (EAE), the animal model of MS, treatment with anti-CD4 antibodies can prevent the onset of disease. Natural history studies have demonstrated that gadolinium enhanced magnetic resonance imaging (MRI) of the brain is more sensitive and objective in assessing inflammatory disease activity in MS than clinical monitoring, so that less patients and shorter studies suffice to reach the same statistical power as compared to trials using clinical outcome parameters. In this paper we describe the design of an exploratory trial of chimeric monoclonal anti-CD4 antibodies in the treatment of MS. For this study we chose the number of active MS lesions on monthly gadolinium enhanced MRI scans as the primary outcome measure.

Adolescent↗
PubMed1996

Accumulation of hypointense lesions ("black holes") on T1 spin-echo MRI correlates with disease progression in multiple sclerosis.

MRI findings are increasingly used as outcome measures in therapeutic trials in MS. The discrepancy between the extent of the lesions on conventional T2 images and the clinical condition of the patient is one of the problems encountered in such studies. This clinical-radiological paradox prevents the use of MRI data as surrogate markers of disability in MS. A recent pilot study suggested a relationship between hypointense lesions on T1 MRI and disability. To assess in more detail the correlation of changes in hypointense lesion load on T1-weighted spin-echo MR images ("black holes") with changes in disability in MS, we studied 46 patients with clinically definite MS at baseline and after a median follow-up of 40 months. There was a significant correlation between baseline disability and hypointense lesion load (Spearman rank correlation coefficient [SRCC] = 0.46, p = 0.001). In secondary progressive patients, the rate of accumulation of these "black holes" was significantly related to progression rate (SRCC = 0.81, p < 0.0001). We speculate that the appearance of hypointense lesions is the MRI equivalent of a failure of remission. Overall, T1 lesion load measurements correlated better with clinical assessments than T2 lesion load measurements. Quantification of hypointense lesion load on T1-weighted spin-echo MRI helps to resolve the clinical-radiological paradox between disability and MRI and has the potential to be a surrogate marker of disability in MS.

Adult↗
PubMed1996

Increased MRI activity and immune activation in two multiple sclerosis patients treated with the monoclonal anti-tumor necrosis factor antibody cA2.

There is evidence that treatment with an antibody to tumor necrosis factor alpha (TNF alpha) improves an animal model of multiple sclerosis (MS) and is beneficial in two systemic inflammatory disease in humans, but there are no reports about anti-TNF treatment of MS. Therefore, we treated two rapidly progressive MS patients with intravenous infusions of a humanized mouse monoclonal anti-TNF antibody (cA2) in an open-label phase I safety trial and monitored their clinical status, gadolinium-enhanced brain magnetic resonance imaging (MRI), and peripheral blood and cerebrospinal fluid (CSF) immunologic status. We did not notice any clinically significant neurologic changes in either patient. The number of gadolinium-enhancing lesions increased transiently after each treatment in both patients. CSF leukocyte counts and IgG index increased after each treatment. The transient increase in the number of gadolinium-enhancing lesions that followed each infusion of cA2 together with the increase in cells and immunoglobulin in the CSF of each patient suggest that the treatment caused immune activation and an increase in disease activity. These results suggest that further use of cA2 in MS is not warranted and that studies of other agents that antagonize TNF alpha should be carried out with frequent monitoring of gadolinium-enhanced MRIs.

Adult↗
PubMed1995

Multiple sclerosis therapy. A practical guide.

A growing amount of evidence suggests that a disturbance of immunological function is of importance in the pathogenesis of multiple sclerosis. This is reflected in the drugs used to slow progression and to treat relapses. Immunosuppressive drugs such as azathioprine, cyclophosphamide and cyclosporin might have some potential to slow down progression of multiple sclerosis, but their use is limited by potentially serious adverse effects. Recently, it was shown that interferon-beta-1b can diminish the exacerbation rate in multiple sclerosis without leading to unacceptable adverse effects. Nevertheless, symptomatic treatment remains of crucial importance in the management of multiple sclerosis patients. Spasticity, depression, fatigue and urinary, paroxysmal and sensory symptoms can all be alleviated to some extent with pharmacological interventions, although rehabilitation procedures and psychosocial consultations are no less important. Further therapeutic approaches to multiple sclerosis will be directed at either the specificity of the immune response or the grade of activation of the immune response. Magnetic resonance imaging techniques will play an important role in the evaluation of efficacy of new therapeutic agents.

Adjuvants, Immunologic↗