Magnetic object assay
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Magnetosensitivity is widespread among animals with rodents being the most intensively studied mammalian group. The available behavioural assays for magnetoreception are time-consuming, which impedes screens for treatment effects that could characterize the enigmatic magnetoreceptors. Here, we present a fast and simple approach to test if an animal responds to magnetic stimuli: the magnetic object assay (MOA). The MOA focuses on investigating an animal's spontaneous exploration behaviour in the presence of a bar magnet compared to a demagnetised control. We present consistently longer exploration of the magnet in three different rodent species: Ansell's mole-rat (Fukomys anselli), C57BL/6J laboratory mouse, and naked mole-rat (Heterocephalus glaber). For the naked mole-rat this is the first report that this species reacts on magnetic stimuli. We conclude that the MOA holds the potential to screen if an animal responds to magnetic stimuli, indicating the possession of a magnetic sense.
OBJECTIVES: Glucose is an important diagnostic biochemical marker of diabetes but also for organophosphates, carbamates, acetaminophens or salicylates poisoning. Hence, innovation of accurate and fast detection assay is still one of priorities in biomedical research. METHODS: Glucose sensor based on magnetic particles (MPs) with immobilized enzymes glucose oxidase (GOx) and horseradish peroxidase (HRP) was developed and the GOx catalyzed reaction was visualized by a smart-phone-integrated camera. RESULTS: Exponential decay concentration curve with correlation coefficient 0.997 and with limit of detection 0.4 mmol/l was achieved. Interfering and matrix substances were measured due to possibility of assay influencing and no effect of the tested substances was observed. Spiked plasma samples were also measured and no influence of plasma matrix on the assay was proved. CONCLUSIONS: The presented assay showed complying results with reference method (standard spectrophotometry based on enzymes glucose oxidase and peroxidase inside plastic cuvettes) with linear dependence and correlation coefficient 0.999 in concentration range between 0 and 4 mmol/l. On the grounds of measured results, method was considered as highly specific, accurate and fast assay for detection of glucose.
- MeSH
- biosenzitivní techniky metody MeSH
- biotest metody normy MeSH
- chytrý telefon využití MeSH
- enzymy imobilizované metabolismus MeSH
- glukosaoxidasa metabolismus MeSH
- křenová peroxidasa metabolismus MeSH
- krevní glukóza metabolismus MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Serum neurofilament light chain (sNfL) is a marker of neuroaxonal injury. There is a lack of studies investigating the dynamics of relationships between sNfL levels and radiological disease activity over long-term follow-up in multiple sclerosis (MS). OBJECTIVES: To investigate the relationship among repeated measures of sNfL, lesion burden accumulation, brain volume loss and clinical measures. METHODS: We investigated 172 patients in the early stages of MS (McDonald 2017 criteria). Clinical exams were performed every 3 months and brain magnetic resonance imaging (MRI) scans were collected annually over 48 months. sNfL levels were measured in serum by Simoa assay at the time of treatment initiation and then annually over 36 months. RESULTS: In repeated-measures analysis, considering all time points, we found a strong relationship between percentage changes of sNfL and lesion burden accumulation assessed by T1 lesion volume (p < 0.001) and T2 lesion number (p < 0.001). There was no relationship between percentage changes of sNfL and brain volume loss over 36 months (p > 0.1). Early sNfL levels were associated with delayed brain volume loss after 48 months (p < 0.001). Patients with No Evidence of Disease Activity (NEDA-3) status showed lower sNfL levels compared with active MS patients. CONCLUSIONS: sNfL is associated with ongoing neuroinflammation and predictive of future neurodegeneration in early MS.
- MeSH
- biologické markery MeSH
- intermediární filamenta MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- mozek diagnostické zobrazování MeSH
- neurofilamentové proteiny MeSH
- roztroušená skleróza * diagnostické zobrazování MeSH
- zánět diagnostické zobrazování MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVES: To address the role of latent T. gondii infection in schizophrenia we studied the influence of latent toxoplasmosis on brain morphology. METHODS: An optimized voxel-based morphometry of magnetic resonance imaging was analyzed by analysis of variance with diagnosis and seropositivity as factors in 44 schizophrenic patients (12 T. gondii positive) and 56 controls (13 T. gondii positive). RESULTS: Grey matter (GM) volume was reduced in schizophrenia patients compared with controls in the cortical regions, hippocampus and in the caudate. In the schizophrenia sample we found a significant reduction of GM volume in T. gondii positive comparing with T. gondii-negative patients bilaterally in the caudate, median cingulate, thalamus and occipital cortex and in the left cerebellar hemispheres. T. gondii-positive and -negative controls did not differ in any cluster. Among participants seropositive to T. gondii the reduction of GM in the schizophrenia subjects was located in the same regions when comparing the entire sample (11,660 over-threshold voxels (P ≤ 0.05, FWR corrected). The differences between T. gondii-negative patients and controls consisted only of 289 voxels in temporal regions. CONCLUSIONS: Our study is the first to document that latent toxoplasmosis reduces GM in schizophrenia but not in controls.
- MeSH
- analýza rozptylu MeSH
- dospělí MeSH
- ELISA MeSH
- hipokampus mikrobiologie patologie MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody MeSH
- mapování mozku metody MeSH
- mozek mikrobiologie patologie MeSH
- mozková kůra mikrobiologie patologie MeSH
- mozková toxoplazmóza komplikace mikrobiologie patologie MeSH
- počítačové zpracování obrazu metody MeSH
- schizofrenie komplikace mikrobiologie patologie MeSH
- spánkový lalok mikrobiologie patologie MeSH
- thalamus mikrobiologie patologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVE: Refractory epilepsy may have an underlying autoimmune etiology. Our aim was to assess the prevalence of neural autoantibodies in a multicenter national prospective cohort of patients with drug-resistant epilepsy undergoing epilepsy surgery utilizing comprehensive clinical, serologic, and histopathological analyses. METHODS: We prospectively recruited patients undergoing epilepsy surgery for refractory focal epilepsy not caused by a brain tumor from epilepsy surgery centers in the Czech Republic. Perioperatively, we collected cerebrospinal fluid (CSF) and/or serum samples and performed comprehensive commercial and in-house assays for neural autoantibodies. Clinical data were obtained from the patients' medical records, and histopathological analysis of resected brain tissue was performed. RESULTS: Seventy-six patients were included, mostly magnetic resonance imaging (MRI)-lesional cases (74%). Mean time from diagnosis to surgery was 21 ± 13 years. Only one patient (1.3%) had antibodies in the CSF and serum (antibodies against glutamic acid decarboxylase 65) in relevant titers; histology revealed focal cortical dysplasia (FCD) III (FCD associated with hippocampal sclerosis [HS]). Five patients' samples displayed CSF-restricted oligoclonal bands (OCBs; 6.6%): three cases with FCD (one with FCD II and two with FCD I), one with HS, and one with negative histology. Importantly, eight patients (one of them with CSF-restricted OCBs) had findings on antibody testing in individual serum and/or CSF tests that could not be confirmed by complementary tests and were thus classified as nonspecific, yet could have been considered specific without confirmatory testing. Of these, two had FCD, two gliosis, and four HS. No inflammatory changes or lymphocyte cuffing was observed histopathologically in any of the 76 patients. SIGNIFICANCE: Neural autoantibodies are a rare finding in perioperatively collected serum and CSF of our cohort of mostly MRI-lesional epilepsy surgery patients. Confirmatory testing is essential to avoid overinterpretation of autoantibody-positive findings.
- MeSH
- autoprotilátky MeSH
- epilepsie * epidemiologie chirurgie komplikace MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- malformace mozkové kůry * komplikace MeSH
- prevalence MeSH
- prospektivní studie MeSH
- refrakterní epilepsie * diagnostické zobrazování chirurgie komplikace MeSH
- retrospektivní studie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
BACKGROUND AND OBJECTIVE: Large deformations in synthetic meshes used in pelvic organ prolapse surgery may lead to suboptimal support for the underlying tissue, graft-related complications as well as recurrence. Our aim was to quantify in vivo longitudinal changes in mesh shape and geometry in a large animal model. We compare two commonly used mesh shapes, armed and flat, that are differently affixed. The secondary outcomes were active and passive biomechanical properties. METHODS: A total of 18 animals were used. Six each were implanted with either an arm mesh, a flat mesh or underwent a sham surgery. PVDF meshes loaded with Fe2O3were used to facilitate their visualization in vivo. MR images were taken at 2, 14 and 60 days after implantation and 3D models of the meshes were created at each time point. We calculate the Effective Surface Area (ESA), i.e. the support that the mesh provides to the underlying tissue using custom developed techniques. Longitudinal changes in the mesh shape were studied by comparing the respective 3D models using part comparison analyses. The root means square difference (RMSD) and the modified Hausdorff distance (MHD) were calculated to obtain an objective value for the part comparisons. Wall thickness maps were produced on 3D models. Mesh arm length and their ellipticity profiles were also evaluated. Active and passive biomechanical tests on vaginal tissue overlaying the mesh were conducted using a contractility assay and a uniaxial loading protocol. RESULTS: MR images of 5 animals in each group were used for longitudinal comparison. Compared to the initial implant size, there was an immediate drop in the ESA measurement at day 2 of almost 32.22 [7.06] % (median [IQR]) for flat meshes, and by 17.59 [6.50] % for arm meshes. After 14 days, the reduction in area was 41.84 [14.89] % and 27.18 [20.44] %, and at day 60 it was 36.61 [6.64] % and 26.43 [14.56] % for the flat and armed meshes respectively. The reduction in area in the two groups was different between the two groups only day 14 (p = 0.046). The ellipticity of the arms was 0.81 [0.08] (median [IQR]) and there was no significant change in the ellipticity profiles over time. The mesh arm length did not change significantly over time. The part comparison showed a maximum difference of 4.26 [3.29] mm in 3D models according to the MHD measure, which is clinically not relevant. Comparison of high thickness areas on the thickness maps correlated well with the areas of mesh folding in the arm mesh group observed during postmortem dissection. Thickness maps did not help us understand why the flat meshes had a reduction in support area. The comfort zone stiffness of the flat mesh and of the central part of the arm mesh were 2.4 fold and 4.5 times stiffer compared to sham groups, respectively. The arms were 36% stiffer than the central part of the mesh. The comfort zone length of the sham group was 46% longer than the flat mesh group (p = 0.027) and 59% longer than that of the central part of the arm mesh (p = 0.005). There was no significant difference in vaginal contractile forces generated in samples from the arm, flat mesh, and sham groups. CONCLUSIONS: This is a first longitudinal study observing deformations in vaginally implanted synthetic meshes in a large animal model. A novel methodology is presented to calculate the area of the vaginal tissue effectively supported by the mesh implant. Immediately post-operatively, a reduction in 32% and 17% was noted, which remained stable over the 60 following days of observation. We use thickness maps to analyze the cause of this dramatic immediate reduction. In the armed mesh we found it to be mesh folding at the interface between the arms and central part. For the flat mesh we suggest that pore aggregation during suturing.
- MeSH
- chirurgické síťky * MeSH
- longitudinální studie MeSH
- magnetická rezonanční tomografie * MeSH
- ovce MeSH
- prolaps pánevních orgánů chirurgie MeSH
- testování materiálů * MeSH
- vagina chirurgie MeSH
- železité sloučeniny MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVE: To evaluate long-term effects of 2-year treatment with interferon beta combined with low-dose azathioprine and prednisone in multiple sclerosis. METHODS: In the original 2-year ASA study, 181 patients with early relapsing-remitting multiple sclerosis were randomised into 3 treatment arms: those treated with interferon beta (n=60), with interferon beta and low-dose azathioprine (n=58), and interferon beta, azathioprine and low-dose prednisone (n=63). Of these, 172 were included in this 4-year non-study extension. Three monthly clinical controls and annual MRI scans were carried out. The primary endpoint was annual relapse activity. The secondary endpoints were disability and quantitative MRI parameters. RESULTS: Nine patients were lost to follow-up and 172 were included in the analyses. None of relapse activity, disability accumulation or MRI parameters differed significantly between the groups over 6 years. Only 5.5% and 0.6% of patients were free from disease activity at year 2 and year 6 of the treatment initiation. CONCLUSION: The tested combined therapeutic regimen does not improve long-term outcomes in patients with multiple sclerosis. Furthermore, interferon is not able to completely abolish disease activity.
- MeSH
- adjuvancia imunologická aplikace a dávkování terapeutické užití MeSH
- azathioprin terapeutické užití MeSH
- dospělí MeSH
- dvojitá slepá metoda MeSH
- hormony kůry nadledvin terapeutické užití MeSH
- imunosupresiva terapeutické užití MeSH
- injekce intramuskulární MeSH
- interferon beta aplikace a dávkování terapeutické užití MeSH
- kohortové studie MeSH
- kombinovaná farmakoterapie MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mozek patologie MeSH
- následné studie MeSH
- neúspěšná terapie MeSH
- posuzování pracovní neschopnosti MeSH
- prednison terapeutické užití MeSH
- progrese nemoci MeSH
- recidiva MeSH
- roztroušená skleróza farmakoterapie patologie MeSH
- stanovení cílového parametru MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- randomizované kontrolované studie MeSH
OBJECTIVE: Diagnosing autoimmune encephalitis (AIE) is difficult in patients with less fulminant diseases such as epilepsy. However, recognition is important, as patients require immunotherapy. This study aims to identify antibodies in patients with focal epilepsy of unknown etiology, and to create a score to preselect patients requiring testing. METHODS: In this prospective, multicenter cohort study, adults with focal epilepsy of unknown etiology, without recognized AIE, were included, between December 2014 and December 2017, and followed for 1 year. Serum, and if available cerebrospinal fluid, were analyzed using different laboratory techniques. The ACES score was created using factors favoring an autoimmune etiology of seizures (AES), as determined by multivariate logistic regression. The model was externally validated and evaluated using the Concordance (C) statistic. RESULTS: We included 582 patients, with median epilepsy duration of 8 years (interquartile range = 2-18). Twenty patients (3.4%) had AES, of whom 3 had anti-leucine-rich glioma inactivated 1, 3 had anti-contactin-associated protein-like 2, 1 had anti-N-methyl-D-aspartate receptor, and 13 had anti-glutamic acid decarboxylase 65 (enzyme-linked immunosorbent assay concentrations >10,000IU/ml). Risk factors for AES were temporal magnetic resonance imaging hyperintensities (odds ratio [OR] = 255.3, 95% confidence interval [CI] = 19.6-3332.2, p < 0.0001), autoimmune diseases (OR = 13.31, 95% CI = 3.1-56.6, p = 0.0005), behavioral changes (OR 12.3, 95% CI = 3.2-49.9, p = 0.0003), autonomic symptoms (OR = 13.3, 95% CI = 3.1-56.6, p = 0.0005), cognitive symptoms (OR = 30.6, 95% CI = 2.4-382.7, p = 0.009), and speech problems (OR = 9.6, 95% CI = 2.0-46.7, p = 0.005). The internally validated C statistic was 0.95, and 0.92 in the validation cohort (n = 128). Assigning each factor 1 point, an antibodies contributing to focal epilepsy signs and symptoms (ACES) score ≥ 2 had a sensitivity of 100% to detect AES, and a specificity of 84.9%. INTERPRETATION: Specific signs point toward AES in focal epilepsy of unknown etiology. The ACES score (cutoff ≥ 2) is useful to select patients requiring antibody testing. ANN NEUROL 2021;89:698-710.
- MeSH
- autoimunitní nemoci diagnostické zobrazování imunologie psychologie MeSH
- autoprotilátky analýza MeSH
- chování MeSH
- dospělí MeSH
- elektroencefalografie MeSH
- epilepsie parciální diagnostické zobrazování imunologie psychologie MeSH
- glutamát dekarboxyláza genetika imunologie MeSH
- kognitivní poruchy etiologie psychologie MeSH
- kohortové studie MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- prospektivní studie MeSH
- rizikové faktory MeSH
- záchvaty diagnostické zobrazování etiologie imunologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- pozorovací studie MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
- Nizozemsko MeSH
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Biomedical and health research, ISSN 0929-6743 vol. 9
xxxix, 744 s. ; 24 cm