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K Beckmann

Publications and source records attributed to K Beckmann.

18 recordsLinked to original sources
PubMed2006

[Case report: equine arteritis virus (EAV) as the cause of abortion in alpacas?].

Here we report a case of a late abortion of a primiparous alpaca where genome fragments of the equine viral arteritis virus (EAV) could be detected in fetal tissues using reverse transcription polymerase chain reaction (RT-PCR). All five alpacas of the herd had virus neutralizing antibodies against EAV. EAV thus must be regarded as a potential agent for abortions in alpacas. Possible routes of introduction of the virus are discussed.

Abortion, Veterinary↗
PubMed2005

Interferon beta-1b treatment does not induce autoantibodies.

BACKGROUND: There is little information regarding the potential of interferon beta (IFNbeta) to induce or exacerbate autoimmune disease. Existing data from uncontrolled studies are contradictory and do not differentiate between autoimmune dysfunction, which is frequent in patients with multiple sclerosis (MS), and untoward drug effects. OBJECTIVE: To evaluate the impact of IFNbeta on hepatic, thyroid, and other markers of autoimmunity using data from the European placebo-controlled double-blind, multicenter study of IFNbeta-1b in patients with secondary progressive MS (SPMS). METHODS: Serum samples obtained at baseline and at 6-month intervals for 24 months were analyzed for the following autoantibodies (AAbs): antinuclear (ANA), antimitochondrial (AMA), smooth muscle (SMA), liver kidney microsome (LKM), thyroid microsome (TPO), and human thyroglobulin (TG). AAb status at baseline and during treatment was related to respective laboratory and clinical deviations. RESULTS: The analysis of AAb data included 355 patients receiving IFNbeta-1b and 353 receiving placebo. There was no difference between treatment groups in de novo AAb positivity. A greater proportion of women were AAb positive at baseline and during treatment. No association was found between liver enzyme elevations and ANA, AMA, or SMA antibody formation in either treatment group. Laboratory-based thyroid alterations during the study were significantly related to TG/TPO status at baseline but were not associated with IFNbeta-1b treatment. Adverse events possibly indicative of other diseases with autoimmune links were not associated with respective AAb status. CONCLUSION: Interferon beta-1b treatment did not induce autoantibody formation in this population of patients with secondary progressive multiple sclerosis.

Autoantibodies↗
PubMed2005

Soluble vascular cell adhesion molecule (VCAM) is associated with treatment effects of interferon beta-1b in patients with secondary progressive multiple sclerosis.

BACKGROUND: Subcutaneous IFNbeta-1b (Betaferon) is an established immunomodulatory treatment for relapsing remitting MS and active secondary progressive multiple sclerosis (SPMS). It modulates cytokine and adhesion molecule expression but long term in vivo effects of IFNbeta-1b on the immune system are not known in multiple sclerosis. OBJECTIVE: To address the effects of IFNbeta-1b on serum levels for soluble adhesion molecules and cytokine receptors from MS patients. METHODS: Serial blood samples were obtained from 40 patients of the frequent MRI subgroup (20 patients each from the placebo and the IFNbeta-1b treatment group), participating in the European multi-center clinical trial with IFNbeta-1b for secondary progressive MS, at regular intervals for up to 36 months. Soluble adhesion molecules (sVCAM, sICAM-1, sL-Selectin) as well as TNF-receptor I and II were analysed in the serum of patients by enzyme linked immunosorbent assays (ELISAs). Monthly brain MRI was performed in 34 of these patients (16 patients from the placebo and 18 from the IFNbeta-1b group) during months 1-6 and 19-24 to monitor disease activity as assessed by newly occurring gadolinium (Gd) enhancing lesions. RESULTS: An early and significant increase in sVCAM and sTNF-RII serum levels was detected in 16 out of 20 patients (80 %) treated with subcutaneous IFNbeta-1b already at month 1 but was absent in all but one patient during placebo treatment (p < 0.01). Raised sVCAM and TNF RII serum levels during months 1-6 inversely correlated with less MRI activity in the 19-24 months treatment interval in the IFNa-1b treatment group ( p = 0.0093 for TNF-RII; p = 0.047 for VCAM). CONCLUSIONS: sVCAM and sTNF RII levels in the serum of SPMS patients are increased during IFNbeta-1b therapy and may at least in part explain some of the treatment effects, like reduced immune cell transmigration.

Adult↗
PubMed2004

Interferon beta-1b in secondary progressive MS: a combined analysis of the two trials.

BACKGROUND: A European (EU) and a North American (NA) placebo-controlled study with interferon beta-1b (IFNB-1b) in secondary progressive multiple sclerosis (SPMS) showed divergent results with regard to their primary outcome of sustained Expanded Disability Status Scale (EDSS) progression, while effects were similar on relapse and MRI-related endpoints. Reasons for this discrepancy were explored in the combined dataset. METHODS: Baseline characteristics and variability in EDSS assessments were compared. Retrospective combined analyses for time to confirmed progression were performed to assess treatment effects overall and in subgroups defined by pre-study disease activity criteria and other key baseline variables. RESULTS: The variance of EDSS measurements was 6.5% higher in the NA-SPMS study. The EU study included patients in an earlier phase of SPMS and with more active disease both pre-study (relapses, MRI) as well as on study (EDSS, relapses, and MRI variables as assessed in the placebo groups). The pooled analysis showed an overall risk reduction by about 20% in patients treated with 8 MIU (250 mcg) IFNB-1b for EDSS progression confirmed at 6 months (p = 0.008). Risk reduction by 30% to 40% was found for patients with at least one relapse or change in EDSS by >1 in the 2 years prior to study entry. No other consistent across-studies relation of clinical and MRI variables at baseline to potential treatment response was found. CONCLUSIONS: Although post hoc, this combined analysis of the two large studies with IFNB-1b in secondary progressive multiple sclerosis suggests that both pronounced disability progression and continuing relapse activity might help in identifying those patients in the secondary progressive phase of the disease who are more likely to benefit from treatment.

Adult↗
PubMed2003

MRI metrics as surrogate endpoints for EDSS progression in SPMS patients treated with IFN beta-1b.

BACKGROUND: Although metrics derived from conventional MRI (cMRI) are widely used as outcome measures in clinical trials of MS, no formal study has been performed to validate cMRI metrics as surrogate endpoints for disability progression in MS. METHODS: A validation procedure was applied to the clinical and MRI data collected in the context of the European randomized, double-blind, placebo-controlled trial of interferon beta-1b (IFNbeta-1b) in patients with secondary progressive MS. The Prentice operational criteria were used to assess surrogacy for the number of active lesions seen on the first year T2-weighted MRI scans and the percentage T2 lesion volume change between the baseline and the first year MRI scans. The primary clinical outcome was disability at study exit (3 years), adjusted for the baseline disability. RESULTS: The number of active T2 lesions and the T2 lesion volume percentage change over the first year of the study accounted for 57% of the treatment effect on disability progression over the entire study duration. On the contrary, the same cMRI metrics accounted for 79% of the treatment effect on the relapse rate. CONCLUSIONS: This study shows that the beneficial effect of IFNbeta-1b on disability accumulation in patients with secondary progressive MS is, to a large extent, independent of the changes detected using cMRI. As a consequence, cMRI metrics should not be used as a stand-alone measure of outcome in phase III trials of IFNbeta in secondary progressive MS.

Biomarkers↗
PubMed2003

The effect of interferon beta-1b on quantities derived from MT MRI in secondary progressive MS.

BACKGROUND: Magnetization transfer (MT) MRI can provide in vivo markers reflecting the severity of irreversible, MS-related brain damage occurring within and outside T2-visible lesions. OBJECTIVE: To assess the effect of interferon (IFN) beta-1b treatment on the accumulation of brain damage in patients with secondary progressive (SP) MS, measured using MT MRI. METHODS: Eighty-two patients with SPMS from five centers participating in a European, multicenter, double-blind, placebo-controlled trial of IFNbeta-1b in SPMS underwent brain T2-weighted and MT MRI at baseline. Evaluable follow-up data were available for 75 patients at 12 months, 54 at 24 months, and 47 at 36 months. MT MRI scans were postprocessed and analyzed to obtain histograms of MT ratio (MTR) values from the whole brain. A region of interest-based analysis of MTR values from the normal-appearing white matter (NAWM) was also performed. RESULTS: In both the treatment arms, there was a decrease of average brain MTR values from baseline to month 24 (mean change -4.9%) and month 36 (mean change -4.3%). These changes were significant for the placebo group at both timepoints and for the IFNbeta-1b group at month 24 only, with no significant treatment effect. A decrease of NAWM MTR was also observed, with no significant difference between the two treatment arms. CONCLUSION: In this cohort of patients with secondary progressive MS, interferon beta-1b did not show an overall effect on the worsening of magnetization transfer MRI measures, when compared with placebo. The data show that change in magnetization transfer ratio is a promising tool for monitoring disease evolution in secondary progressive MS and that the information obtained from magnetization transfer MRI complements that obtained from MRI measures of lesion load and inflammation.

Adult↗
PubMed2003

Neutralizing antibodies during treatment of secondary progressive MS with interferon beta-1b.

OBJECTIVE: To investigate the relationship between neutralizing antibodies (NAB) and disease progression, relapses, and MR measures of MS. METHODS: Sequential serum samples from all 718 patients of the European Study Group in Interferon beta-1b in Secondary Progressive MS were analyzed to investigate relations between NAB and disease progression, relapses, and MR measures. RESULTS: This study showed no attenuating effect of NAB development on progression in disability. The effects of NAB on relapse rate showed substantial variation, depending on the statistical approach and definition of positivity, though analyses comparing low- and high-NAB+ periods with NAB- periods suggested a titer-related effect. MR T2 lesion volume changes from baseline were significantly higher for NAB+ patients but remained lower than for placebo patients. A substantial proportion of NAB+ patients became NAB-. No untoward effect of NAB development on safety was observed. CONCLUSION: These results support the conclusion that even though high NAB titers appear to have impact on treatment efficacy with respect to relapses, treatment decisions should be based primarily on clinical grounds.

Adult↗
PubMed2001

Clinical-MRI correlations in a European trial of interferon beta-1b in secondary progressive MS.

BACKGROUND: The recently completed placebo-controlled multicenter randomized trial of interferon beta-1b (Betaferon) in 718 patients with secondary progressive MS shows significant delay of disease progression and reduction of relapse rate. This study provides an opportunity to assess the level of relationship between clinical and MRI outcomes in this cohort of patients with secondary progressive MS. METHODS: Brain T2-weighted lesion volume was measured annually in all available patients, with visual analysis to identify any new or enlarging (active) T2 lesions at each annual time point. A subgroup of 125 patients had monthly gadolinium-enhanced, T1-weighted imaging at months 0 to 6 and 18 to 24. Relapses were documented and expanded disability status scale (EDSS) was measured every 3 months. RESULTS: For the annual MRI outcomes, a significant but modest correlation was identified between the change in T2 lesion volume from baseline to the final scan and the corresponding change from baseline in EDSS (r = 0.17, p < 0.0001). There were significant correlations between the cumulative number of active T2 lesions and 1) change in EDSS (r = 0.18, p < 0.0001) and 2) relapse rate (r = 0.24, p < 0.0001). In the subgroup of 125 patients undergoing monthly imaging, MRI lesion activity was correlated with relapse rate over months 0 to 24 (r = 0.24, p = 0.006) but not with change in EDSS. CONCLUSIONS: These results confirm that the clinical-MRI relationships previously identified in relapsing-remitting MS still are apparent in the secondary progressive phase of the disease and support the use of MRI as a relevant outcome measure. In view of the relatively modest nature of the correlations, it seems unwise to rely on such MRI measures alone as primary efficacy variables in secondary progressive MS trials.

Brain↗
PubMed2001

Final analysis of the European multicenter trial on IFNbeta-1b in secondary-progressive MS.

BACKGROUND: Based on a prospectively planned interim analysis, the European study of interferon beta-1b (IFNbeta-1b) provided evidence that the treatment delays neurologic deterioration in patients with secondary progressive MS (SPMS). The authors analyzed all data collected until closure of the double-blind study to further scrutinize the consistency of the findings. METHODS: The multicenter, double-blind, randomized, placebo-controlled trial treated patients for up to 36 months. The primary and all secondary endpoints of this study were evaluated using the data set at study termination, with a mean follow-up under double-blind conditions of 1054 +/- 199 and 1068 +/- 176 days for the placebo and IFNbeta-1b group. Alternative and more demanding definitions of disease progression were explored. Confirmed progression was analyzed in subgroups according to baseline demographics and baseline indicators of disease activity. RESULTS: Forty-eight of 358 placebo and 40 of 360 IFNbeta-1b-allocated patients were lost to follow-up. Time to confirmed 1.0-point Expanded Disability Status Scale (EDSS) progression for patients receiving IFNbeta-1b was delayed (p = 0.007). The proportion of patients with a confirmed 2.0-point EDSS progression was approximately 27% lower for the group treated with IFNbeta-1b, both including and excluding EDSS data collected during relapses. The proportion of patients with either progression or relapses decreased by nearly 30% in patients treated with IFNbeta-1b compared with placebo. Analysis of subgroups suggests that patients with higher prestudy disease activity (more than two relapses or EDSS progression by more than 1.0 point or both) seem to have a more pronounced treatment effect. CONCLUSION: Analysis of the data set at study termination including additional post hoc outcome measures is consistent with the original findings, thus supporting the conclusion that treatment with IFNbeta-1b is effective in patients with SPMS fulfilling the inclusion criteria of this study.

Adjuvants, Immunologic↗
PubMed2001

Interferon-beta1b in the treatment of secondary progressive MS: impact on quality of life.

BACKGROUND: The recent randomized, controlled trial of interferon-beta1b (IFN-beta1b) in 718 patients with secondary progressive MS (SP-MS) demonstrated a significant effect on the development of disability as evaluated by the physician. Its effect on patient-reported health-related quality of life (HrQoL) is reported herein. METHODS: In this multicenter, double-blind, randomized, placebo-controlled trial, outpatients with SP-MS scoring between 3.0 and 6.5 on the Expanded Disability Status Scale received either 8 x 10(6) IU of IFN-beta1b or placebo for up to 3 years. A range of outcomes was measured, including HrQoL, which was assessed using the Sickness Impact Profile (SIP), a self-report questionnaire validated for use in MS. Measurements were undertaken at baseline and at 6-monthly intervals thereafter for 36 months. RESULTS: A slight positive effect on the HrQoL of the IFN group in comparison with the placebo group was found, which reached significance in the physical scale of the SIP at 6 and 12 months and at last visit. There was moderate correlation between physician-assessed evaluation of change and patient-reported change. CONCLUSIONS: IFN-beta1b may delay sustained deterioration in patient-reported HrQoL in SP-MS. Methods of interpreting change in HrQoL are currently insufficiently developed to determine how clinically important these changes are for this population.

Activities of Daily Living↗
PubMed2000

The effect of interferon beta-1b treatment on MRI measures of cerebral atrophy in secondary progressive multiple sclerosis. European Study Group on Interferon beta-1b in secondary progressive multiple sclerosis.

The recently completed European trial of interferon beta-1b (IFNbeta-1b) in patients with secondary progressive multiple sclerosis (SP multiple sclerosis) has given an opportunity to assess the impact of treatment on cerebral atrophy using serial MRI. Unenhanced T(1)-weighted brain imaging was acquired in a subgroup of 95 patients from five of the European centres; imaging was performed at 6-month intervals from month 0 to month 36. A blinded observer measured cerebral volume on four contiguous 5 mm cerebral hemisphere slices at each time point, using an algorithm with a high level of reproducibility and automation. There was a significant and progressive reduction in cerebral volume in both placebo and treated groups, with a mean reduction of 3.9 and 2.9%, respectively, by month 36 (P = 0.34 between groups). Exploratory subgroup analyses indicated that patients without gadolinium (Gd) enhancement at the baseline had a greater reduction of cerebral volume in the placebo group (mean reduction at month 36: placebo 5.1%, IFNbeta-1b 1.8%, P < 0.05) whereas those with Gd-enhancing lesions showed a trend to greater reduction of cerebral volume if the patient was on IFNbeta-1b (placebo 2.6%, IFNbeta-1b 3.7%; P > 0.05). These results are consistent with ongoing tissue loss in both arms of this study of secondary progressive multiple sclerosis. This finding is concordant with previous observations that disease progression, although delayed, is not halted by IFNbeta. The different pattern seen in patients with and without baseline gadolinium enhancement suggests that part of the cerebral volume reduction observed in IFNbeta-treated patients may be due to the anti-inflammatory/antioedematous effect of the drug. Longer periods of observation and larger groups of patients may be needed to detect the effects of treatment on cerebral atrophy in this population of patients with advanced disease.

Adult↗
PubMed1999

[Effects of the K(+) channel blocker tedisamil on hemodynamics, myocardial ischemia and neurohumoral systems in patients with stable angina pectoris. A comparison with the beta blocker atenolol].

BACKGROUND: Clinical drawbacks of beta-blocker treatment in stable angina have motivated researchers to provide alternative heart rat lowering agents, such as tedisamil which additionally exerts anti-ischemic and antiarrhythmic effects by blockade of cellular repolarizing K(+) currents. METHODS AND RESULTS: 48 patients with stable angina pectoris were investigated (double-blind, randomized, parallel grouped) comparing the hemodynamic, anti-ischemic, metabolic and neurohumoral effects of tedisamil 100 mg b.i.d and atenolol 50 mg b.i.d. after a single dose and over 6 days of treatment. Tedisamil and atenolol produced a decrease in heart rate both at rest (day 1: -13.6 vs -15.4 bpm; p > 0.05; day 6: -14.8 vs -22.2 bpm; resp.; p > 0.05) and exercise (day 1: -9.1 vs -18.3 bpm; p = 0. 001; day 6: -12.0 vs -24.8 bpm, resp.; p = 0.001), while anginal threshold increased. Cardiac output decreased with tedisamil and atenolol at rest (day 1: -1.01 vs -1.19 l/min; p > 0.05; day 6: -0. 86 vs -1.10 l/min, resp.; p > 0.05) and exercise (day 1: -0.82 vs -1. 28 l/min; p > 0.05; day 6: -0.65 vs -2.68 l/min, resp.; p = 0.03), while stroke volume remained unchanged. Right atrial pressure changed during exercise only: It decreased with tedisamil (-1.7 mm Hg) and increased with atenolol (+3.7 mm Hg). Mean pulmonary capillary wedge pressures decreased at rest (-0.5 mm Hg) and exercise (-6.9 mm Hg) in the tedisamil group, but tended to increase with atenolol on day 6 (rest: +1.7; exercise: +3.7 mm Hg) (p = 0.03). Arterial pressure decreased under atenolol treatment only. Exercise-induced plasma norepinephrine levels were reduced by tedisamil (-93 pg/ml) but elevated by atenolol (+172 pg/ml) (p = 0. 001). As compared to atenolol, tedisamil produced a significant prolongation of QT (c) interval (+31 vs -8 ms) (p = 0.002) at initial values of 0.408 +/- 0.018 s with PQ and QRS remaining unaltered. CONCLUSIONS: In the present study, tedisamil (100 mg b.i.d. ) generated favorable hemodynamic, neurohumoral and anti-ischemic effects in patients with stable angina pectoris. The anti-ischemic efficacy of tedisamil, as measured by ST segment depression and angina threshold, is comparable to that of atenolol (50 mg b.i.d.).

Adrenergic beta-Antagonists↗
PubMed1999

Pharmacodynamic comparison of single doses of IFN-beta1a and IFN-beta1b in healthy volunteers.

In a study in 75 volunteers, preparations of interferon-beta1b (IFN-beta1b) and IFN-beta1a were compared in terms of the resulting serum concentrations of three biologic markers, neopterin, human Mx protein, and 2',5' oligoadenylate synthetase. Each preparation was tested at five dose levels, the middle dose being that recommended for use in patients with multiple sclerosis on the basis of large clinical trials. Five randomly chosen volunteers each received a single subcutaneous dose of one of the IFN or of IFN-beta1a given intramuscularly. The amounts of each marker induced were dose related. There were no major differences between the results with the two IFN or in the duration of the changes in the markers after the two routes of injection. The data indicated that 8 million international units (MIU) of IFN-beta1b and 6 MIU of IFN-beta1a had very similar effects. Even after the highest single dose tested, the increase in the biologic markers were not sustained for a full week.

2',5'-Oligoadenylate Synthetase↗
PubMed1997

Photosynthesis and fluorescence quenching, and the mRNA levels of plastidic glutamine synthetase or of mitochondrial serine hydroxymethyltransferase (SHMT) in the leaves of the wild-type and of the SHMT-deficient stm mutant of Arabidopsis thaliana in relation to the rate of photorespiration.

The regulation by photorespiration of the transcript level corresponding to plastidic glutamine synthetase (GS-2) was investigated in the leaves of Arabidopsis thaliana (L.) Heynh.. Photorespiration was suppressed by growing the plants in an atmosphere containing 300 Pa CO2. Suppression of photorespiration was demonstrated by the ability of the conditionally lethal serine hydroxymethyltransferase (SHMT)-deficient stm mutant of A. thaliana to grown normally under these conditions. In contrast to previous studies with bean or pea that were performed at very high CO2 partial pressure (2-4 kPa; Edwards and Coruzzi, 1989, Plant Cell 1:241-248; Cock et al., 1991, Plant Mol Biol 17: 761-771), suppression of photorespiration during growth of A. thaliana in an atmosphere with 300 Pa CO2 had no effect of the leaf GS-2 transcript level. In the short term, neither suppression of photorespiration induced by the transfer of air-grown A. thaliana plants into a CO2-enriched atmosphere, nor an increase in the rate of photorespiration achieved by the transfer of high-CO2-grown A. thaliana plants into air resulted in a change in the GS-2 mRNA level. The absence of photorespiratory ammonium release in leaves of the stm mutant had no effect on the GS-2 transcript level. Overall, our data argue against a control by photorespiration of the A. thaliana leaf GS-2 mRNA pool. In contrast, regulation of the leaf SHMT mRNA level may involve a negative feedback effect of at least one metabolite derived from the glycine/serine conversion during photorespiration, as indicated by the overexpression of SHMT transcripts in the leaves of the stm mutant.

Arabidopsis↗
PubMed1996

Cerebral tissue oxygenation during hypoxia and hyperoxia using artificial placentation in lamb.

Aiming at a better understanding of the pathophysiologic basis of perinatal encephalopathy, we evaluated patterns of tissue oxygenation during hypoxia and hyperoxia. We utilized both laserspectroscopy and invasive tissue-Po2 microneed measurements synchronously in five newborn lambs (141-143 days of gestation). The model of artificial placentation provided defined changes of the blood gases, using a extracorporeal circuit with interposition of membrane lung. During hyperoxia, the Po2 at the blood outlet port of the lung was raised to > 300 mmHg for five minutes. During hypoxia, Po2 was diminished as oxygen at the gas phasis was replaced by nitrogen. After the induction of hyperoxia, a rise of tissue-Po2 was observed. The synchronously recorded data of the laserspectroscopy showed adequately rising HbO2 values in concordance (r = 0.97, p < 0.001). As a constant finding we did not observe Cyt-aa3 changes during induced hyperoxia with tissue-Po2 values of < 40 mmHg. Furthermore, no changes in blood volume occurred in this case. A different pattern of the laserspectroscopic parameters was found when the tissue-Po2 rose above a value of > 40 mmHg and Cyt-aa3 rose after a lag-time occurred. During induced hypoxia an immediate fall of tissue-Po2 corresponding with a fall of HbO2 in the spectroscopic tracing occurred (r = 0.87, p < 0.001). A fall of the Cyt-aa3 level was seen with a lag-time when the tissue-Po2 had reached values of below 10 mmHg. In addition, a rise of blood volume was recorded in all cases of induced hypoxia. In conclusion, the results indicated that cellular redoxe state remains stable over a large range of oxygen partial pressure changes.

Animals↗