918 resultados para Parabolic Subgroup
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ABSTRACT BACKGROUND: Chronic mountain sickness (CMS) is a major public health problem characterized by exaggerated hypoxemia and erythrocytosis. In more advanced stages, these patients often present functional and structural changes of the pulmonary circulation, but there is little information on the systemic circulation. In patients suffering from diseases associated with chronic hypoxemia at low altitude, systemic vascular function is altered. We hypothesized that patients with CMS display systemic vascular dysfunction that may predispose them to increased systemic cardiovascular morbidity. METHODS: To test this hypothesis, we assessed systemic endothelial function (by flow- mediated dilation, FMD), arterial stiffness and carotid intima-media thickness and arterial oxygenation (SaO(2)) in 23 patients with CMS without additional classical cardiovascular risk factors and 27 age-matched healthy mountain dwellers born and permanently living at 3600 m. For some analyses subjects were classified according to baseline SaO(2) quartiles; FMD of the highest quartile subgroup (SaO(2) ≥90%) was used as reference value for post-hoc comparisons. RESULTS: Patients with CMS displayed marked systemic vascular dysfunction, as evidenced by impaired FMD (4.6±1.2 vs. 7.6±1.9%, CMS vs. controls, P<0.0001), greater pulse wave velocity (10.6±2.1 vs. 8.4±1.0 m/s, P<0.001) and carotid intima-media thickness (690±120 vs. 570±110 μm, P=0.001). A positive relationship existed between SaO(2) and FMD (r=0.62, P<0.0001). Oxygen inhalation improved (P<0.001), but did not normalize FMD in patients with CMS; whereas it normalized FMD in hypoxemic controls (SaO(2) <90%) and had no detectable effect in normoxemic (SaO(2) ≥90%) control subjects. CONCLUSIONS: Patients with CMS display marked systemic vascular dysfunction. Structural and functional alterations contribute to this problem that may predispose these patients to premature cardiovascular disease. Clinical Trials Gov Registration # NCT01182792.
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Meiosis in triploids faces the seemingly insuperable difficulty of dividing an odd number of chromosome sets by two. Triploid vertebrates usually circumvent this problem through either asexuality or some forms of hybridogenesis, including meiotic hybridogenesis that involve a reproductive community of different ploidy levels and genome composition. Batura toads (Bufo baturae; 3n = 33 chromosomes), however, present an all-triploid sexual reproduction. This hybrid species has two genome copies carrying a nucleolus-organizing region (NOR+) on chromosome 6, and a third copy without it (NOR-). Males only produce haploid NOR+ sperm, while ova are diploid, containing one NOR+ and one NOR- set. Here, we conduct sibship analyses with co-dominant microsatellite markers so as (i) to confirm the purely clonal and maternal transmission of the NOR- set, and (ii) to demonstrate Mendelian segregation and recombination of the NOR+ sets in both sexes. This new reproductive mode in vertebrates ('pre-equalizing hybrid meiosis') offers an ideal opportunity to study the evolution of non-recombining genomes. Elucidating the mechanisms that allow simultaneous transmission of two genomes, one of Mendelian, the other of clonal inheritance, might shed light on the general processes that regulate meiosis in vertebrates.
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One hundred de novo multiple myeloma patients with t(4;14) treated with double intensive therapy according to IFM99 protocols were retrospectively analyzed. The median overall survival (OS) and event-free survival (EFS) were 41.4 and 21 months, respectively, as compared to 65 and 37 for patients included in the IFM99 trials without t(4;14) (P<10(-7)). We identified a subgroup of patients presenting at diagnosis with both low beta(2)-microglobulin <4 mg/l and high hemoglobin (Hb) >/=10 g/l (46% of the cases) with a median OS of 54.6 months and a median EFS of 26 months, respectively, which benefits from high-dose therapy (HDT); conversely patients with one or both adverse prognostic factor (high beta(2)-microglobulin and/or low Hb) had a poor outcome. The achievement of either complete response or very good partial response after HDT was also a powerful independent prognostic factor for both OS and EFS.
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STUDY DESIGN: Computed tomography-based anatomical study. OBJECTIVE: To study the secular changes in lumbar spinal canal dimensions. SUMMARY OF BACKGROUND DATA: Development of symptomatic lumbar spinal stenosis, among other factors, is related to the dimensions of the bony canal. The canal reaches its adult size early on in life. Several factors, including protein intake, may influence its final dimensions. As with increases in human stature from improvements of socioeconomic conditions, we hypothesized that adult bony canal size has also grown larger in recent generations. METHODS: This study analyzes computed tomographic reconstructions from 184 subjects performed for either trauma (n = 81) or abdominal pathologies (n = 103) and born either between 1940 and 1949 (n = 88) or 1970 and 1979 (n = 96). The cross-sectional area of the bony canal was digitally measured at the level of the pedicle (i.e., at a level not influenced by degenerative changes) for each lumbar vertebra. Intra- and interobserver reliability was assessed. RESULTS: Intra- and interobserver measurement reliability were excellent (interclass correlation coefficient = 0.87) and good (interclass correlation coefficient = 0.61), respectively. Contrary to our hypothesis, the 1940-1949 generation patient group exhibited larger lumbar canals at all levels as compared with the 1970-1979 group. Statistically this difference was highly significant (P < 0.001) and particularly pronounced in the trauma subgroup. CONCLUSION: Given that human stature evolution has stabilized and adult height is established during the first 2 years of long bone growth, it is possible that antenatal factors are responsible for this surprising finding. Maternal smoking and age may be possible explanations. This finding may have significant implications. An increasing number of patients may emerge with lumbar spinal stenosis as degenerative changes develop, putting a strain on health resources. Further studies in different population groups and countries will be important to further confirm this trend. LEVEL OF EVIDENCE: 3.
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BACKGROUND: Thymostimulin is a thymic peptide fraction with immune-mediated cytotoxicity against hepatocellular carcinoma (HCC) in vitro and palliative efficacy in advanced HCC in two independent phase II trials. The aim of this study was to assess the efficacy of thymostimulin in a phase III trial. METHODS: The study was designed as a prospective randomised, placebo-controlled, double-blind, multicenter clinical phase III trial. Between 10/2002 and 03/2005, 135 patients with locally advanced or metastasised HCC (Karnofsky >or=60%/Child-Pugh <or= 12) were randomised to receive thymostimulin 75 mg s.c. 5x/week or placebo stratified according to liver function. Primary endpoint was twelve-month survival, secondary endpoints overall survival (OS), time to progression (TTP), tumor response, safety and quality of life. A subgroup analysis according to liver function, KPS and tumor stage (Okuda, CLIP and BCLC) formed part of the protocol. RESULTS: Twelve-month survival was 28% [95%CI 17-41; treatment] and 32% [95%CI 19-44; control] with no significant differences in median OS (5.0 [95% CI 3.7-6.3] vs. 5.2 [95% CI 3.5-6.9] months; p = 0.87, HR = 1.04 [95% CI 0.7-1.6]) or TTP (5.3 [95%CI 2.0-8.6] vs. 2.9 [95%CI 2.6-3.1] months; p = 0.60, HR = 1.13 [95% CI 0.7-1.8]). Adjustment for liver function, Karnofsky status or tumor stage did not affect results. While quality of life was similar in both groups, fewer patients on thymostimulin suffered from accumulating ascites and renal failure. CONCLUSIONS: In our phase III trial, we found no evidence of any benefit to thymostimulin in the treatment of advanced HCC and there is therefore no justification for its use as single-agent treatment. The effect of thymostimulin on hepato-renal function requires further confirmation. TRIAL REGISTRATION: Current Controlled Trials ISRCTN64487365.
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The pursuit of high response rates to minimise the threat of nonresponse bias continues to dominate decisions about resource allocation in survey research. Yet a growing body of research has begun to question this practice. In this study, we use previously unavailable data from a new sampling frame based on population registers to assess the value of different methods designed to increase response rates on the European Social Survey in Switzerland. Using sampling data provides information about both respondents and nonrespondents, making it possible to examine how changes in response rates resulting from the use of different fieldwork methods relate to changes in the composition and representativeness of the responding sample. We compute an R-indicator to assess representativity with respect to the sampling register variables, and find little improvement in the sample composition as response rates increase. We then examine the impact of response rate increases on the risk of nonresponse bias based on Maximal Absolute Bias (MAB), and coefficients of variation between subgroup response rates, alongside the associated costs of different types of fieldwork effort. The results show that increases in response rate help to reduce MAB, while only small but important improvements to sample representativity are gained by varying the type of effort. These findings lend further support to research that has called into question the value of extensive investment in procedures aimed at reaching response rate targets and the need for more tailored fieldwork strategies aimed both at reducing survey costs and minimising the risk of bias.
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In sharp contrast to birds and mammals, most cold-blooded vertebrates have homomorphic (morphologically undifferentiated) sex chromosomes. This might result either from recurrent X-Y recombination (occurring e.g. during occasional events of sex reversal) or from frequent turnovers (during which sex-determining genes are overthrown by new autosomal mutations). Evidence for turnovers is indeed mounting in fish, but very few have so far been documented in amphibians, possibly because of practical difficulties in identifying sex chromosomes. Female heterogamety (ZW) has long been established in Bufo bufo, based on sex reversal and crossing experiments. Here, we investigate a sex-linked marker identified from a laboratory cross between Palearctic green toads (Bufo viridis subgroup). The F(1) offspring produced by a female Bufo balearicus and a male Bufo siculus were phenotypically sexed, displaying an even sex ratio. A sex-specific marker detected in highly reproducible AFLP genotypes was cloned. Sequencing revealed a noncoding, microsatellite-containing fragment. Reamplification and genotyping of families of this and a reciprocal cross showed B. siculus to be male heterogametic (XY) and suggested the same system for B. balearicus. Our results thus reveal a cryptic heterogametic transition within bufonid frogs and help explain patterns of hybrid fitness within the B. viridis subgroup. Turnovers of genetic sex-determination systems may be more frequent in amphibians than previously thought and thus contribute to the prevalence of homomorphic sex chromosomes in this group.
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Non-malignant inflammatory sensory polyganglionopathy (NISP) is the most common form of acquired ganglionopathies, a rare and distinct subgroup of peripheral nerve diseases characterized by a primary degeneration of sensory neurons in dorsal root ganglia. There is a rational for the use of immune modifying agents (IMA) in NISP since an underlying auto-immune process is demonstrated or suspected. However, commonly used IMA such as corticosteroids, azathioprine, methotrexate or IVIG do not prevent disease's progression in the majority of patients. The use of newer IMA, especially those directed against B-cells, may be a therapeutic alternative. An interesting candidate is rituximab, a mouse-human chimeric anti CD20 antibody that specifically eliminates B-cells and B-cells precursors.Objectives: This is a prospective open label pilot study to determine the efficacy of rituximab treatment in NISP patients, who did not respond to commonly used IMA.Methods: Five patients (40% male) with a mean age of 55 years (range 49-67), diagnosed with NISP after extensive work-up, were treated (schema used for one cure: 2 9 1gr within 15 days interval). Neurological scores (NIS, ISSS, ODSS) and B cell counts were assessed at baseline and during clinical follow-up at 2 and 6 monthsto assess treatment efficacy.Results: The treatment was generally well tolerated. Minor adverse events reported were transient arterial hypotension during the infusions in two patients and intermittent mild leucopenia in one patient. Clinical evolution during the follow-up period was characterized by a stability of the functional scores in four patients (80%) and the continuation of disability progression of one patient (20%). CD4 cells disappeared in all patients after the second infusion, an effect that lasted until the follow up at 6 months.Conclusion: The preliminary results of this pilot study indicate that rituximab is generally well tolerated and prevents progression of disability during the 6-month observation period in NISP patients. Inclusion of additional patients and extending of the follow-up period are intended to further investigate the efficacy of rituximab in NISP.
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Introduction: Diffuse large B-cell lymphomas (DLBCL) represent a heterogeneous disease with variable clinical outcome. Identifying phenotypic biomarkers of tumor cells on paraffin sections that predict different clinical outcome remain an important goal that may also help to better understand the biology of this lymphoma. Differentiating non-germinal centre B-cell-like (non-GCB) from Germinal Centre B-cell-like (GCB) DLBCL according to Hans algorithm has been considered as an important immunohistochemical biomarker with prognostic value among patients treated with R-CHOP although not reproducibly found by all groups. Gene expression studies have also shown that IgM expression might be used as a surrogate for the GCB and ABC subtypes with a strong preferential expression of IgM in ABC DLBCL subtype. ImmunoFISH index based on the differential expression of MUM-1, FOXP1 by immunohistochemistry and on the BCL6 rearrangement by FISH has been previously reported (C Copie-Bergman, J Clin Oncol. 2009;27:5573-9) as prognostic in an homogeneous series of DLBCL treated with R-CHOP. In addition, oncogenic MYC protein overexpression by immunohistochemistry may represent an easy tool to identify the consequences of MYC deregulation in DLBCL. Our aim was to analyse by immunohistochemistry the prognostic relevance of MYC, IgM, GCB/nonGCB subtype and ImmunoFISH index in a large series of de novo DLBCL treated with Rituximab (R)-chemotherapy (anthracyclin based) included in the 2003 program of the Groupe d'Etude des Lymphomes de l'Adulte (GELA) trials. Methods: The 2003 program included patients with de novo CD20+ DLBCL enrolled in 6 different LNH-03 GELA trials (LNH-03-1B, -B, -3B, 39B, -6B, 7B) stratifying patients according to age and age-adjusted IPI. Tumor samples were analyzed by immunohistochemistry using CD10, BCL6, MUM1, FOXP1 (according to Barrans threshold), MYC, IgM antibodies on tissue microarrays and by FISH using BCL6 split signal DNA probes. Considering evaluable Hans score, 670 patients were included in the study with 237 (35.4%) receiving intensive R-ACVBP regimen and 433 (64.6%) R-CHOP/R-mini-CHOP. Results: 304 (45.4%) DLBCL were classified as GCB and 366 (54.6%) as non-GCB according to Hans algorithm. 337/567 cases (59.4%) were positive for the ImmunoFISH index (i.e. two out of the three markers positive: MUM1 protein positive, FOXP1 protein Variable or Strong, BCL6 rearrangement). Immunofish index was preferentially positive in the non-GCB subtype (81.3%) compared to the GCB subtype (31.2%), (p<0.001). IgM was recorded as positive in tumor cells in 351/637 (52.4%) DLBCL cases with a preferential expression in non-GCB 195 (53.3%) vs GCB subtype 100(32.9%), p<0.001). MYC was positive in 170/577 (29.5%) cases with a 40% cut-off and in 44/577 (14.2%) cases with a cut-off of 70%. There was no preferential expression of MYC among GCB or non-GCB subtype (p>0.4) for both cut-offs. Progression-free Survival (PFS) was significantly worse among patients with high IPI score (p<0.0001), IgM positive tumor (p<0.0001), MYC positive tumor with a 40% threshold (p<0.001), ImmunoFISH positive index (p<0.002), non-GCB DLBCL subtype (p<0.0001). Overall Survival (OS) was also significantly worse among patients with high IPI score (p<0.0001), IgM positive tumor (p=0.02), MYC positive tumor with a 40% threshold (p<0.01), ImmunoFISH positive index (p=0.02), non-GCB DLBCL subtype (p<0.0001). All significant parameters were included in a multivariate analysis using Cox Model and in addition to IPI, only the GCB/non-GCB subtype according to Hans algorithm predicted significantly a worse PFS among non-GCB subgroup (HR 1.9 [1.3-2.8] p=0.002) as well as a worse OS (HR 2.0 [1.3-3.2], p=0.003). This strong prognostic value of non-GCB subtyping was confirmed considering only patients treated with R- CHOP for PFS (HR 2.1 [1.4-3.3], p=0.001) and for OS (HR 2.3 [1.3-3.8], p=0.002). Conclusion: Our study on a large series of patients included in trials confirmed the relevance of immunohistochemistry as a useful tool to identify significant prognostic biomarkers for clinical use. We show here that IgM and MYC might be useful prognostic biomarkers. In addition, we confirmed in this series the prognostic value of the ImmunoFISH index. Above all, we fully validated the strong and independent prognostic value of the Hans algorithm, daily used by the pathologists to subtype DLBCL.
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BACKGROUND AND AIMS: Mannan-binding lectin (MBL) and ficolins are microbial pattern recognition molecules that activate the lectin pathway of complement. We previously reported the association of MBL deficiency with anti-Saccharomyces cerevisiae antibodies (ASCA) in patients with Crohn's disease (CD). However, ASCA are also frequently found in MBL-proficient CD patients. Here we addressed expression/function of ficolins and MBL-associated serine protease-2 (MASP-2) regarding potential association with ASCA. METHODS: ASCA titers and MBL, ficolin and MASP-2 concentrations were determined by ELISA in the serum of patients with CD, ulcerative colitis (UC), and in healthy controls. MASP-2 activity was determined by measuring complement C4b-fixation. Anti-MBL autoantibodies were detected by ELISA. RESULTS: In CD and UC patients, L-ficolin concentrations were significantly higher compared to healthy controls (p<0.001 and p=0.029). In contrast, H-ficolin concentrations were slightly reduced in CD and UC compared to healthy controls (p=0.037 for UC vs. hc). CD patients with high ASCA titers had significantly lower H-ficolin concentrations compared to ASCA-low/negative CD patients (p=0.009). However, MASP-2 activity was not different in ASCA-negative and ASCA-positive CD patients upon both, ficolin- or MBL-mediated MASP-2 activation. Finally, anti-MBL autoantibodies were not over-represented in MBL-proficient ASCA-positive CD patients. CONCLUSIONS: Our results suggest that low expression of H-ficolin may promote elevated ASCA titers in the ASCA-positive subgroup of CD patients. However, unlike MBL deficiency, we found no evidence for low expression of serum ficolins or reduced MASP-2 activity that may predispose to ASCA development.
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Purpose of reviewMedulloblastomas are very rare in adults. Usual treatment consists of craniospinal radiation with or without chemotherapy. Current efforts focus on a better understanding of tumour biology, stratifying patients into risk groups and adapting treatment accordingly. This review discusses clinical and new molecular risk factors that will help to optimize treatment in adult medulloblastoma patients.Recent findingsThe clinical risk stratification should be complemented with new molecular prognostic markers. Gene-expression profiling has permitted identification of four to six molecular medulloblastoma subgroups. The WNT subgroup shows overexpression of genes of the WNT/wingless signalling pathway with frequent mutations of the CNNTB1 gene, loss of chromosome 6 and accumulation of nuclear beta-catenin, and is most often seen in children with medulloblastomas of classical histology. This variant has a good prognosis. Activation of the sonic hedgehog pathway with frequent mutations of the PTCH and SUFU genes, loss of 9q, and positivity for GLI1 and SFRP1 is more frequent in children less than 3 years old and in adults, commonly associated with desmoplastic histology. Other subgroups are not so well defined and have overlapping characteristics, but MYC/MYCN amplification, 17q gain and, large cell/anaplastic histology are factors of poor prognosis.SummaryNew molecular subgroups will help tailor treatment and further develop new targeted therapies. Prospective and ideally randomized trials should be performed in adults, including risk stratification by molecular markers, to identify optimal treatment for each risk group.
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Objective: To assess the impact of patient admission in different hospital types in Switzerland on early in-hospital and 1-year outcomes in patients with acute coronary syndrome (ACS).Methods: From 1997 to 2009, 31,010 ACS patients from 76 Swiss hospitals were enrolled in the AMIS Plus registry. Large tertiary teaching institutions with 24 hour/7 day cardiac catheterization facilities were classified as type A hospitals, all others as type B. One-year outcome was studied in a subgroup of patients admitted after 2005. Multivariate logistic regression models were used to calculate the odds ratios (OR with 95%CI) for independent predictors of mortality and major adverse cardiac events (MACE).Results: There were 11 type A hospitals with admissions of 15,987 (52%) patients and 65 type B hospitals with 15,023 (48%) patients. Patients initially admitted into B hospitals were older, more frequently female, hypertensive and diabetic, had more severe comorbidities and more frequently NSTE-ACS/UA. They were less likely to receive aspirin, clopidogrel and GPIIb/IIIa antagonists. STE-ACS patients initially admitted into B hospitals received more thrombolysis than those admitted into A hospitals, but less percutaneous coronary intervention (PCI). From the patients admitted to B hospitals, 5271 (35%) were transferred for intervention. Crude in-hospital mortality and MACE were higher in patients from B hospitals. Crude 1-year mortality of 3747 ACS patients followed up was higher in patients initially admitted into B hospitals, but no differences were found for MACE. Hospital type, after adjustment for age, risk factors, type of ACS and co-morbidities, was not an independent predictor of in-hospital mortality (OR 0.94; 0.76-1.16), in-hospital MACE (0.98; 0.82-1.17), 1-year mortality or 1-year MACE (1.06; 0.85-1.33). Analysis of the time of admission indicated a crude outcome in favor of hospitalization during duty-hours but no significant effect could be documented for 1-year outcome.Conclusion: ACS patients admitted to type B hospitals were older, had more severe co-morbidities, more NSTEACS and received less intensive treatment. However, after correcting for baseline inequalities, early and mid-term outcomes were similar regardless of hospital type. Ultimate patient outcome thus does not appear to be influenced by the type of hospital where the initial admission takes place. Appropriate early referral of selected patients probably partly explains this finding.
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OBJECTIVE: Studies investigating medication adherence in psychosis are limited by the need of a certain degree of medication adherence and the inclusion of mostly multiple-episode patients. By contrast, noninformed consent, epidemiological studies in first-episode psychosis (FEP) allow the assessment of an important subgroup of patients who persistently refuse antipsychotic medication and thereby never receive an adequate antipsychotic trial. The present study aims to assess the prevalence and predictors of such a "medication refusal" subgroup and its association with illness outcome. METHODS: The present file audit study assessed medication adherence in an epidemiological cohort of 605 FEP patients who were treated within the Early Psychosis Prevention and Intervention Centre for up to 18 months. Medication adherence was categorized into full adherence, nonadherence, and persistent medication refusal. Predictors were analyzed using logistic regression models. RESULTS: During the 18-month treatment period, 204 patients (33.7%) were fully adherent, 287 (47.4%) displayed at least 1 phase of nonadherence, and 114 patients (18.8%) were persistent medication refusers. Poor premorbid functioning, comorbid substance use, and poor insight predicted both medication refusal and nonadherence; a forensic history and no previous contact to psychiatric care were specifically predictive of medication refusal. With respect to illness outcome, nonadherent patients were worse off when compared with fully adherent patients, and medication refusers were even worse off compared with nonadherent patients. CONCLUSIONS: Within a nonselected epidemiological FEP cohort, almost 20% of patients are persistent medication refusers. The found predictors may help to identify the individual risk of persistent medication refusal and may enable an early (preventive) treatment adaptation.
Mortality of patients with COPD participating in chronic disease management programmes: a happy end?
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BACKGROUND: Concerns about increased mortality could question the role of COPD chronic disease management (CDM) programmes. We aimed at extending a recent Cochrane review to assess the effects of CDM on mortality in patients with COPD. METHODS: Mortality data were available for 25 out of 29 trials identified in a COPD integrated care systematic review. Meta-analysis using random-effects models was performed, followed by subgroup analyses according to study length (3-12 months vs >12 months), main intervention component (exercise, self-management, structured follow-up) and use of an action plan. RESULTS: The meta-analysis showed no impact of CDM on mortality (pooled OR: 1.00, 95% CI 0.79 to 1.28). CONCLUSIONS: These results do not suggest that CDM programmes expose patients with COPD to excessive mortality risk.
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BACKGROUND: Modafinil has anecdotal response to neurological fatigue, but such an effect may depend on the type and location of cerebral impairment. OBJECTIVES: It was the aim of this study to compare fatigue observed in different neurological pathologies, to evaluate the tolerability to modafinil, and to describe changes in subjective fatigue. METHODS: We enrolled 14 brainstem or diencephalic stroke (BDS) patients, 9 cortical stroke (CS) patients and 17 multiple sclerosis (MS) patients. The Fatigue Assessment Instrument severity scale was performed at baseline, after 3 months of modafinil and after 1 month of washout. Cognition, mood and somnolence were assessed. A subgroup of 14 patients underwent activity measures before and during treatment. RESULTS: Thirty-one patients completed the study (10 BDS, 9 CS, 12 MS). The responder profile is more frequent in MS than in CS (p = 0.04), and in BDS than in CS patients (p = 0.04). Actiwatch measures showed no changes in activity during, before and after therapy. CONCLUSION: Modafinil was tolerated in 75% of patients at small doses and seemed to improve the severity of fatigue in the MS and BDS groups but not in the CS group. There was no modification in measured physical activity.