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Publications and source records attributed to A Steck.
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RATIONALE: Phase I/II studies of autologous hematopoietic stem cell transplantation (HSCT) for multiple sclerosis ( MS) were initiated, based on results of experimental transplantation in animal models of multiple sclerosis and clinical observations in patients treated concomitantly for malignant disease. PATIENTS: Eighty-five patients with progressive MS were treated with autologous HSCT in 20 centers and reported to the autoimmune disease working party of the European Group for Blood and Marrow Transplantation (EBMT). 52 (61 %) were female, median age was 39 [20-58] years. The median interval from diagnosis to transplant was 7 [1-26] years. Patients suffered from severe disease with a median EDSS score of 6.5 [4.5-8.5]. Active disease prior to transplant was documented in 79 of 82 evaluable cases. RESULTS: The stem cell source was bone marrow in 6 and peripheral blood in 79, and stem cells were mobilized into peripheral blood using either cyclophosphamide combined with growth factors or growth factors alone. Three patients experienced transient neurological complications during the mobilization phase. The high dose regimen included combination chemotherapy, with or without anti-lymphocyte antibodies or, with or without, total body irradiation. The stem cell transplants were purged of lymphocytes in 52 patients. Median follow-up was 16 [3-59] months. There were 7 deaths, 5 due to toxicity and infectious complications, 2 with neurological deterioration. The risk of death of any cause at 3 years was 10 (+/-7)% (95 % confidence interval). Neurological deterioration during transplant was observed in 22 patients; this was transient in most but was associated with MS progression in 6 patients. Neurological improvement by > or = 1 point in the EDSS score was seen in 18 (21 %) patients. Confirmed progression-free survival was 74 (+/-12)% at 3 years being 66 (+/-23)% in patients with primary progressive MS but higher in patients with secondary progressive or relapsing-remitting MS, 78 (+/-13)%; p = 0.59. The probability of confirmed disease progression was 20 (+/-11)%. MRI data were available in 78 patients before transplant showing disease activity (gadolinium enhancing, new or enlarging lesions) in 33 %. Posttransplant MRI showed activity at any time in 5/61 (8 %) evaluable cases. CONCLUSION: Autologous HSCT suggest positive early results in the management of progressive MS and is feasible. These multicentre data suggest an association with significant mortality risks especially in some patient groups and are being utilised in the planning of future trials to reduce transplant related mortality.
The clinical and laboratory phenotype of a paraproteinaemic neuropathy syndrome termed chronic sensory ataxic neuropathy with anti-disialosyl IgM antibodies is described in a series of 18 cases. Previous single case reports have outlined some features of this syndrome. All 18 cases were defined by the presence of serum IgM antibodies which react principally with NeuAc (alpha2-8)NeuAc(alpha2-3)Gal-configured disialosyl epitopes common to many gangliosides including GDlb, GD3, GTlb and GQlb. In 17 out of 18 cases, the serum contained benign IgM paraproteins, and in four of these cases at least two IgM paraproteins were present. The IgM antibodies were also cold agglutinins in 50% of cases. The clinical picture comprised a chronic neuropathy with marked sensory ataxia and areflexia, and with relatively preserved motor function in the limbs. In addition, 16 out of 18 cases had motor weakness affecting oculomotor and bulbar muscles as fixed or as relapsing-remitting features. When present in their entirety, these clinical features have been described previously under the acronym CANOMAD: chronic ataxic neuropathy, ophthalmoplegia, IgM paraprotein, cold agglutinins and disialosyl antibodies. This distribution of clinical features is reminiscent of Miller Fisher syndrome, in which acute-phase anti-disialylated ganglioside IgG antibodies are found. Clinical electrophysiology and nerve biopsy show both demyelinating and axonal features. A partial response to intravenous immunoglobulin and other treatments is reported in some cases.
The possible occurrence of chronic inflammatory demyelinating polyneuropathy (CIDP) in association with an identified dysglobulinemic status is recognized and a causal relationship between the two has been suggested. We had the opportunity to study 18 patients presenting with CIDP and dysglobulinemia. This was an IgG monoclonal gammopathy (IgG MG) in 8 cases, an IgM monoclonal gammopathy (IgM MG) in 8, an IgG-IgM biclonal gammopathy in 1 case and an IgM monoclonal cryoglobulinemia in another. A peripheral nerve biopsy specimen was available for all patients and the morphological findings in these specimens in the cases of CIDP with IgG MG or cryoglobulin did not differ from those without, whereas characteristic features were observed in the cases of CIDP with IgM MG and anti-myelin associated glycoprotein activity.
A few studies have reported a variety of nonspecific histological lesions in patients with IgA monoclonal gammopathies and polyneuropathy. In our case, using electron microscopy, we observed widenings of the myelin lamellae identical to those commonly described in IgM neuropathies with anti-myelin-associated glycoprotein activity. Using immunoelectron microscopy, we demonstrated a direct involvement of IgA in myelin lesions. The search for a direct link between monoclonal dysglobulinemia, regardless of type, and polyneuropathy is important and may influence treatment.
Sixteen carotenoids were isolated from the flesh of Brazilian red guavas (Psidium guajava L.). Their structures were established by means of UV-visible, 400 and 500 MHz (1)H NMR, 120 and 125 MHz (13)C NMR, mass, and circular dichroism spectra. The carotenoids were identified as phytofluene, (all-E)-, (9Z)-, (13Z)-, and (15Z)-beta-carotene, (all-E)-gamma-carotene, (all-E)-, (9Z)-, (13Z)-, and (15Z)-lycopene, (all-E,3R)-beta-cryptoxanthin, (all-E, 3R)-rubixanthin, (all-E,3S,5R,8S)-cryptoflavin, (all-E,3R,3'R, 6'R)-lutein, (all-E,3S,5R,6R,3'S,5'R,8'R)-, and (all-E,3S,5R,6R,3'S, 5'R,8'S)-neochrome. Thirteen of the carotenoids identified are reported as guava carotenoids for the first time.
(13Z,13'Z,3R,3'R,6'R)-Lutein has been isolated and purified from extracts of marigold flowers, fresh raw kale (Brassica oleracea var. Acephala), and human plasma and fully characterized by (1)H and (13)C NMR, UV/vis, and MS. While the concentration of (13Z, 13'Z)-lutein in kale and human plasma compared to (all-E,3R,3'R, 6'R)-lutein was found to be quite low, this compound was readily isolated by fractional crystallization of lutein from marigold extracts. Thus, the mother liquors from two consecutive crystallizations of lutein from a saponified extract of marigold flowers were enriched in (13Z,13'Z)-lutein (8.7% of total carotenoids) and employed for the isolation of this compound by HPLC. The identity of the di-Z-lutein in kale and human plasma has been established by comparison of the HPLC-UV/vis-MS profiles of the purified compounds with those of a fully characterized sample, isolated from marigolds. 3-Hydroxy-beta,epsilon-caroten-3'-one and 3'-epilutein have also been identified in extracts from marigolds.
Acute porphyrias are inherited disorders caused by partial deficiency of specific heme biosynthesis enzymes. Clinically, porphyrias are manifested by a neuropsychiatric syndrome that includes peripheral neuropathy. Although much is known about the porphyrias' enzyme defects and their biochemical consequences, the cause of the neurological manifestations remains unresolved. We have studied porphyric neuropathy in mice with a partial deficiency of porphobilinogen deaminase (PBGD). PBGD-deficient mice (PBGD-/-) imitate acute porphyria through massive induction of hepatic delta-aminolevulinic acid synthase by drugs such as phenobarbital. Here we show that PBGD-/- mice develop impairment of motor coordination and muscle weakness. Histologically femoral nerves of PBGD-/- mice exhibit a marked decrease in large-caliber (>8 microm) axons and ultrastructural changes consistent with primary motor axon degeneration, secondary Schwann cell reactions, and axonal regeneration. These findings resemble those found in studies of affected nerves of patients with acute porphyria and thus provide strong evidence that PBGD deficiency causes degeneration of motor axons without signs of primary demyelination, thereby resolving a long-standing controversy. Interestingly, the neuropathy in PBGD-/- mice developed chronically and progressively and in the presence of normal or only slightly (twofold) increased plasma and urinary levels of the putative neurotoxic heme precursor delta-aminolevulinic acid. These data suggest that heme deficiency and consequent dysfunction of hemeproteins can cause porphyric neuropathy.
QUESTIONS UNDER STUDY: It has been shown that the prognosis of patients with stroke can be improved by specialized stroke units. Whether any additional benefit can be achieved by use of intensive care resources is unknown. Therefore, it was the purpose of this study to analyze our first experience of management of patients with acute ischaemic stroke in an intensive care unit, as part of a newly implemented coordinated stroke concept. METHODS: A consecutive series of 88 patients with acute ischemic stroke (age 64.4 +/- 14.2 years, 28% females) hospitalized in a medical intensive care unit according to predefined criteria formed the study population. The goals were to monitor vital functions, to complete diagnostic studies in timely fashion and to prevent and treat complications. RESULTS: The patients were hospitalized in the intensive care unit for a mean period of 34.4 +/- 19.5 hours. Relevant pathologic findings included systolic hypertension > 220 mm Hg in 5% and permanent or intermittent relative systolic hypotension < 150 mm Hg in 25% and 98% of patients respectively. One patient (1%) died during the stay. Additional diagnostic studies were performed more often in patients with progressive or fluctuating symptoms (100% of patients in each group) than in those with improving or stable symptoms (50% of patients in each group). Fourteen percent of patients were treated for hypertension and 30% for hypotension. Antithrombotic therapy with aspirin was started in 34%, prophylaxis for venous thrombosis with low dose heparin in 39% and systemic anticoagulation in 40% of patients respectively. No cardiac or pulmonary complications requiring treatment were observed and no specific therapies for neurologic complications were utilized. At the time of discharge from the intensive care unit, 88% of patients showed improved or stable neurologic findings. CONCLUSIONS: In the present analysis, an unexpectedly high incidence of relative arterial hypotension was observed in patients hospitalized in an intensive care unit for acute ischaemic stroke. Therapeutic measures were restricted mainly to blood pressure control and anticoagulation/antithrombotic treatment. Specific therapies for neurologic complications or interventions requiring the resources of an intensive care unit were not used. Whether defined patient groups with ischaemic stroke will benefit from specific treatment in an intensive care unit needs to be tested by controlled, randomized studies.
Bioassay-guided fractionation of the dichloromethane rootbark extract of Entada abyssinica (Leguminosae), a plant used by traditional healers in Uganda for the treatment of sleeping sickness, led to the isolation of a diastereoisomer of the clerodane type diterpene kolavenol. This is the first report on this compound. It showed a trypanocidal activity with an IC50 value of 2.5 microg/ml (8.6 microM) against Trypanosoma brucei rhodesiense, the causing agent of the acute form of human African trypanosomiasis.
Thirty-four carotenoids, including 13 geometrical isomers and eight metabolites, in breast milk and serum of three lactating mothers have been separated, identified, quantified, and compared by high-performance liquid chromatography (HPLC)-photodiode array (PDA) detection-mass spectrometry (MS). Among the metabolites were two oxidation products of lycopene and four of lutein/ zeaxanthin. In addition, two metabolites of lutein, formed as a result of dehydration of this dihydroxycarotenoid under acidic conditions similar to those of the stomach, have also been identified in plasma and breast milk. The oxidative metabolites of lycopene with a novel five-membered-ring end group have been identified as epimeric 2,6-cyclolycopene-1,5-diols by comparison of their HPLC-UV/visible-MS profiles with those of fully characterized (1H- and 13C-NMR spectroscopy) synthetic compounds. The HPLC procedures employed also detected vitamin A, two forms of vitamin E (gamma- and alpha-tocopherol), and two non-carotenoid food components, i.e., piperine and caffeine, in serum and breast milk.
To investigate the pathophysiology of fatigue in MS, we assessed cerebral glucose metabolism (CMR-Glu) in 47 MS patients using PET and 18F-fluorodeoxyglucose. Applying the Fatigue Severity Scale (FSS), we first compared MS patients with severe fatigue (MS-FAT, n = 19, FSS > 4.9) and MS patients without fatigue (MS-NOF, n = 16, FSS < 3.7) on a pixel-by-pixel basis using Statistical Parametric Mapping (SPM95). Second, we compared FSS values of all 47 patients covering the whole range of this scale with CMRGlu using an analysis of covariance (SPM95). In addition, we determined global CMRGlu by region-of-interest analysis. Sixteen healthy subjects served as control subjects (CON). Global CMRGlu was significantly lower in both MS groups compared with CON (CON 43.3 +/- 6.9 mumol/100 mL/min, MS-FAT 34.7 +/- 4.4, MS-NOF 35.4 +/- 4.5) but was not related to fatigue severity. Comparing the two MS groups, SPM95 analysis revealed predominant CMRGlu reductions bilaterally in a prefrontal area involving the lateral and medial prefrontal cortex and adjacent white matter, in the premotor cortex, putamen, and in the right supplementary motor area of MS-FAT. In addition, there were CMRGlu reductions in the white matter extending from the rostral putamen toward the lateral head of the caudate nucleus. FSS values were inversely related to CMRGlu in the right prefrontal cortex. CMRGlu in the cerebellar vermis and anterior cingulate was relatively higher in MS-FAT than in MS-NOF patients. CMRGlu of both regions showed positive correlations with FSS values. Our data suggest that fatigue in MS is associated with frontal cortex and basal ganglia dysfunction that could result from demyelination of the frontal white matter.
We studied 33 patients presenting with a peripheral neuropathy associated with non-malignant anti-myelin-associated glycoprotein (MAG) IgM monoclonal gammopathy (MG) in an attempt to delineate their clinical, immunological, electrophysiological and pathological characteristics; we also reviewed our experience concerning long-term follow-up and therapy. Peripheral neuropathy associated with non-malignant anti-MAG IgM MG was observed mostly in males (sex ratio 7.2), and mean age at onset was 67 years (range 46-81). A predominantly sensory pattern was noted in more than 80% of cases, although some patients were affected by a predominantly motor peripheral neuropathy. Although disease progression was slow in most cases, 45% of patients suffered severe disability, and in 2 cases, the patient's death appeared to stem directly from the neuropathy. The electrophysiological findings were indicative of a demyelinating process in 90% of cases, and electron microscopic examination of nerve biopsy specimens demonstrated widening of the myelin lamellae in more than 95% of cases. Most of our patients showed a disappointing response to steroids and chemotherapy or plasma exchanges. Intravenous immune globulin, evaluated in 17 patients, had a transient, mostly subjective effect in 35% and led to a clear-cut improvement in 24% of cases. We did not observe any correlation between the severity of the clinical picture and the anti-sulphoglucuronyl paragloboside antibody titre; in individual cases, clinical improvement occurred without lowering of IgM levels. Although the severity and the rate of progression may greatly vary from patient to patient, the combination of clinical, electrophysiological and pathological features delineates a characteristic pattern in peripheral neuropathy associated with non-malignant anti-MAG IgM MG.
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Fourteen patients with peripheral neuropathy and monoclonal IgG of undetermined significance are reported with a retrospective study of the clinical features, electrophysiologic and sural nerve biopsy findings. There were two groups. Five patients had a relapsing chronic sensorimotor polyneuropathy with clinical (5/5), electrophysiologic (4/5) and pathologic (5/5) features compatible with chronic inflammatory demyelinating polyneuropathies (CIDP). The nine others had a slowly progressive sensory (5/9) (SPNP) or sensorimotor (4/9) (SMPNP) axonal polyneuropathy. Four patients of the first group were treated with intravenous human immunoglobulin (400 mg/kg/day for five days) with significant clinical improvement. The motor conduction velocities and distal latencies of two of these patients improved following treatment, thus matching the clinical improvement. Our results on peripheral nerve biopsies confirm the differentiation of patients with CIDP from those with SMPNP and SPNP. There was no specific immunologic serologic reactivity in any of the cases.
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In the present report, an unusual case of recurrent Miller Fisher syndrome is described. The patient presented within ten years three similar episodes of ophthalmoplegia, ataxia and areflexia associated with oropharyngeal weakness and signs of mild distal sensory neuropathy. An elevated titer of anti-GQ1b ganglioside antibodies correlated well with the clinical symptoms and signs. The pathogenic role of these antibodies in Miller Fisher syndrome is discussed.