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Dive into the research topics where Martin Bojar is active.

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Featured researches published by Martin Bojar.


Annals of Neurology | 2001

Randomized controlled trial of intravenous immunoglobulin versus oral prednisolone in chronic inflammatory demyelinating polyradiculoneuropathy

Richard Hughes; Peter Van den Bergh; S Bensa; Hugh J. Willison; Giancarlo Comi; I. Illa; Eduardo Nobile-Orazio; P. A. van Doorn; Marinos C. Dalakas; Martin Bojar; Anthony V Swan

This multicenter, randomized, double‐blind, crossover trial compared a 6 week course of oral prednisolone tapering from 60 mg to 10 mg daily with intravenous immunoglobulin (IVIg) 2.0 g/kg given over 1 to 2 days for treating chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Twenty‐four of the thirty‐two randomized patients completed both treatment periods. Both treatments produced significant improvements in the primary outcome measure, change in an 11‐point disability scale 2 weeks after randomization. There was slightly, but not significantly, more improvement after IVIg than with prednisolone, the mean difference between the groups in change in disability grade being 0.16 (95% CI = –0.35 to 0.66). There were also slightly, but not significantly, greater improvements favoring IVIg in the secondary outcome measures: time to walk 10 meters after 2 weeks and improvement in disability grade after 6 weeks. Results may have been biased against IVIg by the 8 patients who did not complete the second arm of the trial. A serious adverse event (psychosis) attributable to treatment occurred in 1 patient while on prednisolone and in none with IVIg.


Cell Transplantation | 2006

Autologous bone marrow transplantation in patients with subacute and chronic spinal cord injury.

Eva Syková; Aleš Homola; Mazanec R; Lachmann H; Konrádová Sl; Kobylka P; Pádr R; Neuwirth J; Komrska; Vávra; Stulík J; Martin Bojar

Stem cell transplants into spinal cord lesions may help to improve regeneration and spinal cord function. Clinical studies are necessary for transferring preclinical findings from animal experiments to humans. We investigated the transplantation of unmanipulated autologous bone marrow in patients with transversal spinal cord injury (SCI) with respect to safety, therapeutic time window, implantation strategy, method of administration, and functional improvement. We report data from 20 patients with complete SCI who received transplants 10 to 467 days postinjury. The follow-up examinations were done at 3, 6, and 12 months after implantation by two independent neurologists using standard neurological classification of SCI, including the ASIA protocol, the Frankel score, the recording of motor and somatosensory evoked potentials, and MRI evaluation of lesion size. We compared intra-arterial (via catheterization of a. vertebralis) versus intravenous administration of all mononuclear cells in groups of acute (10–30 days post-SCI, n = 7) and chronic patients (2–17 months postinjury, n = 13). Improvement in motor and/or sensory functions was observed within 3 months in 5 of 6 patients with intra-arterial application, in 5 of 7 acute, and in 1 of 13 chronic patients. Our case study shows that the implantation of autologous bone marrow cells appears to be safe, as there have been no complications following implantation to date (11 patients followed up for more than 2 years), but longer follow-ups are required to determine that implantation is definitively safe. Also, we cannot yet confirm that the observed beneficial effects were due to the cell therapy. However, the outcomes following transplantation in acute patients, and in one chronic patient who was in stable condition for several months prior to cell implantation, are promising. It is evident that transplantation within a therapeutic window of 3–4 weeks following injury will play an important role in any type of stem cell SCI treatment. Trials involving a larger population of patients and different cell types are needed before further conclusions can be drawn.


Proceedings of the National Academy of Sciences of the United States of America | 2007

Spatial navigation deficit in amnestic mild cognitive impairment

Jakub Hort; Jan Laczó; Martin Vyhnalek; Martin Bojar; J. Bureš; Kamil Vlcek

Patients with Alzheimers disease (AD) frequently have difficulties with spatial orientation in their day-to-day life. Although AD is typically preceded by amnestic mild cognitive impairment (MCI), spatial navigation has not yet been studied in MCI. Sixty-five patients were divided into five groups: probable AD (n = 21); MCI, further classified as amnestic MCI single domain (n = 11); amnestic MCI multiple domain (n = 18), or nonamnestic MCI (n = 7), and subjective memory complaints (n = 8). These patients, together with a group of healthy control subjects (n = 26), were tested by using a four-subtests task that required them to locate an invisible goal inside a circular arena. Each subtest began with an overhead view of the arena showed on a computer monitor. This was followed by a real navigation inside of the actual space, an enclosed arena 2.9 m in diameter. Depending on the subtest, the subjects could use the starting position and/or cues on the wall for navigation. The subtests thus were focused on allocentric and egocentric navigation. The AD group and amnestic MCI multiple-domain group were impaired in all subtests. The amnestic MCI single-domain group was impaired significantly in subtests focused on allocentric orientation and at the beginning of the real space egocentric subtest, suggesting impaired memory for allocentric and real space configurations. Our results suggest that spatial navigation impairment occurs early in the development of AD and can be used for monitoring of the disease progression or for evaluation of presymptomiatic AD.


Journal of Neurology | 2002

A randomised controlled trial of intravenous immunoglobulin in IgM paraprotein associated demyelinating neuropathy

Giancarlo Comi; Luisa Roveri; Antony Swan; Hugh J. Willison; Martin Bojar; Isabel Illa; Clementine Karageorgiou; Eduardo Nobile-Orazio; Peter Van den Bergh; Tony Swan; Richard Hughes

Abstract. This multicentre randomised double blind crossover trial tested the short term efficacy of intravenous immunoglobulin (IVIg) 2.0 g/kg given over 24 or 48 hours in patients with paraproteinaemic demyelinating neuropathy (PDN). Twenty-two patients were randomised and completed the trial. After 2 weeks, the overall disability grade decreased during both IVIg treatment and placebo but neither change was significant nor was the mean difference between the treatment effects. After 4 weeks the overall disability decreased by a mean of 0.55 [0.67] grades during the IVIg period (p = 0.001) while it was substantially unmodified during the placebo period. The mean difference between the treatment effects was significant (p = 0.05). Overall during the IVIg period 10 patients improved and 11 were stable and one got worse. During the placebo period 4 patients improved, 4 deteriorated and 14 were stable. Many secondary outcome measures, including Rankin scale, time to walk 10 metres, grip strength, sensory symptoms score were significantly better during IVIg treatment. Two serious adverse events occurred during the trial, both during placebo treatment. In conclusion the trial showed some short-term benefit of IVIg in about half of the patients confirming previous observation.


Behavioural Brain Research | 2009

Spatial navigation testing discriminates two types of amnestic mild cognitive impairment

Jan Laczó; Kamil Vlcek; Martin Vyhnalek; Olga Vajnerová; Michael Ort; Iva Holmerová; Martin Tolar; Ross Andel; Martin Bojar; Jakub Hort

The hippocampus is essential for consolidation of declarative information and spatial navigation. Alzheimers disease (AD) diagnosis tends to be preceded by a long prodromal period and mild cognitive impairment (MCI). Our goal was to test whether amnestic MCI comprises two different subgroups, with hippocampal and non-hippocampal memory impairment, that vary with respect to spatial navigation ability. A total of 52 patients were classified into two subgroups: non-amnestic MCI (naMCI) (n=10) and amnestic MCI (aMCI) (n=42). The aMCI subgroup was further stratified into memory impairment of hippocampal type-hippocampal aMCI (HaMCI) (n=10) (potential preclinical AD) and isolated retrieval impairment-non-hippocampal (NHaMCI) (n=32). Results were compared to control (n=28) and AD (n=21) groups. We used the Hidden Goal Task, a human analogue of the Morris Water Maze, to examine spatial navigation either dependent (egocentric) or independent of individuals position (allocentric). Overall, the HaMCI group performed poorer on spatial navigation than the NHaMCI group, especially in the latter trials when the HaMCI group exhibited limited capacity to learn and the NHaMCI group exhibited a learning effect. Finally, the HaMCI group performed almost identically as the AD group. Spatial navigation deficit is particularly pronounced in individuals with hippocampus-related memory impairment and may signal preclinical AD.


Neurodegenerative Diseases | 2011

Spatial Navigation and APOE in Amnestic Mild Cognitive Impairment

Jan Laczó; Ross Andel; Kamil Vlcek; Václav Macoška; Martin Vyhnalek; Martin Tolar; Martin Bojar; Jakub Hort

Background: The effect of APOE Ε4 allele (Ε4) on spatial navigation in amnestic mild cognitive impairment (aMCI) is unknown. Objective: Our purpose was to examine the characteristics of spatial navigation impairment in Ε4-positive (Ε4+) and Ε4-negative (Ε4–) aMCI subgroups. Methods: Blood samples were collected to determine the APOE genotype. A total of 34 aMCI patients were stratified into aMCI-Ε4– (n = 23) and aMCI-Ε4+ (n = 11) groups. Control (n = 28) and mild Alzheimer’s disease (AD; n = 16) groups were also used. We used a human analogue of the Morris water maze (enclosed arena 2.9 m in diameter) to examine body-centered (egocentric) and world-centered (allocentric) spatial navigation. Results: The aMCI-Ε4+ group performed poorer on spatial navigation than the aMCI-Ε4– group in both egocentric and allocentric tasks even though these 2 groups did not differ in global cognitive functioning or neuropsychological tests. The aMCI-Ε4+ and mild AD groups performed similarly on all Morris Water Maze tasks and were outperformed by the aMCI-Ε4– group, which also resembled the control group in performance on the egocentric tasks. The aMCI groups showed poor spatial navigation learning regardless of their Ε4 positivity. Conclusion: We found more profound deficits in spatial navigation in aMCI-Ε4+ relative to aMCI-Ε4– patients. The aMCI-Ε4+ group resembled the mild AD group in spatial navigation performance. Although the Ε4 genotype was indicative of spatial navigation performance, it was not indicative of the aMCI patients’ ability to learn the tasks. Spatial navigation testing represents a promising area with respect to identifying individuals at higher risk for AD among the heterogeneous MCI population.


Neurodegenerative Diseases | 2012

From Morris Water Maze to computer tests in the prediction of Alzheimer's disease.

Jan Laczó; Ross Andel; Martin Vyhnalek; Kamil Vlcek; Hana Magerova; Alexandra Varjassyova; Z. Nedelska; Ivana Gazova; Martin Bojar; K. Sheardova; J. Hort

Background: Spatial navigation performance in the Hidden Goal Task (HGT), a real-space human analogue of the Morris Water Maze, can identify amnestic mild cognitive impairment (aMCI) patients with memory impairment of the hippocampal type, a known indicator of incipient Alzheimer’s disease (AD). Objective: Contrast results from computer versus real-space versions of the HGT. Methods: A total of 42 aMCI patients were clinically and neuropsychologically classified into: (1) memory impairment of the hippocampal type – the hippocampal aMCI (HaMCI; n = 10) and (2) isolated retrieval impairment – the nonhippocampal aMCI (NHaMCI; n = 32). Results were compared to the control (n = 28) and AD (n = 21) groups. Results: The HaMCI group, although similar to the NHaMCI group with respect to overall cognitive impairment, performed poorer on the computer version of the HGT and yielded parallel results to the real-space version. The two versions were strongly correlated. Conclusions: Both versions of the HGT can reliably identify aMCI with pronounced memory impairment of the hippocampal type. The computer version of the HGT may be a useful, relatively inexpensive screening tool for early detection of individuals at a high risk of AD.


Acta Neurologica Scandinavica | 2006

Amygdalar volume and psychiatric symptoms in Alzheimer's disease: an MRI analysis

Daniel Horinek; Pavel Petrovicky; Jakub Hort; Jan Krasensky; J. Brabec; Martin Bojar; Manuela Vaneckova; Z. Seidl

Objectives –  We measured the volumes of the amygdala to test the hypothesis that the reduction of amygdalar volume may be associated with psychiatric symptoms in Alzheimers disease.


Cell Transplantation | 2017

Transplantation of Mesenchymal Stromal Cells in Patients with Amyotrophic Lateral Sclerosis: Results of Phase I/IIa Clinical Trial:

Eva Syková; Petr Rychmach; Ivana Drahorádová; Šimona Konrádová; Kateřina Růžičková; Ivan Voříšek; Serhiy Forostyak; Aleš Homola; Martin Bojar

Amyotrophic lateral sclerosis (ALS) is a progressive untreatable neurodegenerative disorder, leading to the death of the cortical and spinal motoneurons (MNs). Bone marrow-derived mesenchymal stem/stromal cells (BM-MSCs) may represent a new approach to slowing down the progression of ALS by providing neurotrophic support to host MNs and by having an anti-inflammatory effect. We have designed a prospective, nonrandomized, open-label clinical trial (phase I/IIa, EudraCT No. 2011-000362-35) to assess the safety and efficacy of autologous multipotent BM-MSCs in ALS treatment. Autologous BM-MSCs were isolated and expanded under GMP conditions. Patients received 15 ± 4.5 × 106 of BM-MSCs via lumbar puncture into the cerebrospinal fluid. Patients were monitored for 6 months before treatment and then for an 18-month follow-up period. Potential adverse reactions were assessed, and the clinical outcome was evaluated by the ALS functional rating scale (ALSFRS), forced vital capacity (FVC), and weakness scales (WSs) to assess muscle strength on the lower and upper extremities. In total, 26 patients were enrolled in the study and were assessed for safety; 23 patients were suitable for efficacy evaluation. After intrathecal BM-MSC application, about 30% of the patients experienced a mild to moderate headache, resembling the headaches after a standard lumbar puncture. No suspected serious adverse reactions (SUSAR) were observed. We found a reduction in ALSFRS decline at 3 months after application (p < 0.02) that, in some cases, persisted for 6 months (p < 0.05). In about 80% of the patients, FVC values remained stable or above 70% for a time period of 9 months. Values of WS were stable in 75% of patients at 3 months after application. Our results demonstrate that the intrathecal application of BM-MSCs in ALS patients is a safe procedure and that it can slow down progression of the disease.


American Journal of Alzheimers Disease and Other Dementias | 2014

Odor identification in frontotemporal lobar degeneration subtypes.

Hana Magerova; Martin Vyhnalek; Jan Laczó; Ross Andel; Irena Rektorová; Alexandra Kadlecova; Martin Bojar; Jakub Hort

Odor identification impairment is a feature of several neurodegenerative disorders. Although neurodegenerative changes in the frontotemporal lobar degeneration (FTLD) subtypes involve areas important for olfactory processing, data on olfactory function in these patients are limited. An 18-item, multiple-choice odor identification test developed at our memory clinic, the Motol Hospital smell test, was administered to 9 patients with behavioral variant frontotemporal dementia, 13 patients with the language variants, primary nonfluent aphasia (n = 7) and semantic dementia (n = 6), and 8 patients with progressive supranuclear palsy. Compared to the control group (n = 15), all FTLD subgroups showed significant impairment of odor identification (P < .05). The differences between the FTLD subgroups were not significant. No correlation between odor identification and neuropsychological tests results was found. Our data suggest that odor identification impairment is a symptom common to FTLD syndromes, and it seems to be based on olfactory structure damage rather than cognitive decline.

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Martin Vyhnalek

Charles University in Prague

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Jakub Hort

Charles University in Prague

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Jan Laczó

Charles University in Prague

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Hana Magerova

Charles University in Prague

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Kamil Vlcek

Academy of Sciences of the Czech Republic

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Ross Andel

University of South Florida

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Zuzana Nedelska

Charles University in Prague

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Ales Tomek

Charles University in Prague

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