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Magnetic resonance imag ing (MRI) is cur rently a key component of multiple sclerosis dia gnostics. In addition to conventional techniques, based on the evaluat ion of the number and localization of visible brain and spinal cord lesions, in recent years we have seen a rapid development of new MRI techniques provid ing new quantitative bio markers which better characterize pathological structural changes in central nervous system tis sues occur r ing due to a demyelinat ing dis ease. This article sum marizes new trends in MRI dia gnostics of multiple sclerosis in terms of the technical foundations of diff erent methods, pos sibilities for data analysis and their practical use. [ABSTRACT FROM AUTHOR]

Immunoproteomic analysis was applied to study the immunoreactivity of serum samples collected at different time points from a laboratory assistant accidentally infected with highly virulent strain of Francisella tularensis subsp. tularensis. Immunoblotting showed that the spectrum of F. tularensis antigens recognized specifically by immune sera remained with the exception for 1 antigen stable for up to 16 years after infection. Using immunoproteomics approach 10 immunoreactive antigens were successfully identified. Several new immunogenic F. tularensis proteins were described for the first time. [ABSTRACT FROM AUTHOR]

Heat-shock proteins (hsp) are ubiquitously produced molecules which participate in the protection of cells from environmental perturbation. Moreover, the members of the heat-shock protein 60 (hsp60) and 70 (hsp70) families play an important role in pathogen-host interactions. We studied in vivo production of the 70-kDa heat-shock proteins in the extract of peritoneal exudate cells (PEC) from mice injected intraperitoneally with an attenuated vaccine strain (LVS) of Francisella tularensis. We found a differential production of a highly stress-inducible member of the hsp70 family, designated hsp72, in three inbred strains of mice exhibiting either resistance or susceptibility to F. tularensis LVS infection. Whereas in tularemia-resistant mice hsp72 was even expressed in PEC without injection of bacteria and its production further increased on day 3 and slowly declined on days 5 and 7 after injection, in susceptible mice hsp72 production was highly inducble and restricted only to day 3 after in vivo infection. Further analysis of hsp72 expression revealed intracellular hsp72 accumulation and its preferential production by peritoneal adherent cells. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: Although the gold standard in predicting future progression from clinically isolated syndrome (CIS) to clinically definite multiple sclerosis (CDMS) consists in the McDonald criteria, efforts are being made to employ various advanced MRI techniques for predicting clinical progression. This study's main aim was to evaluate the predictive power of diffusion tensor imaging (DTI) of the brain and brain volumetry to distinguish between patients having CIS with future progression to CDMS from those without progression during the following 2 years and to compare those parameters with conventional MRI evaluation., Materials and Methods: All participants underwent an MRI scan of the brain. DTI and volumetric data were processed and various parameters were compared between the study groups., Results: We found significant differences between the subgroups of patients differing by future progression to CDMS in most of those DTI and volumetric parameters measured. Fractional anisotropy of water diffusion proved to be the strongest predictor of clinical conversion among all parameters evaluated, demonstrating also higher specificity compared to evaluation of conventional MRI images according to McDonald criteria., Conclusion: Conclusion: Our results provide evidence that the evaluation of DTI parameters together with brain volumetry in patients with early-stage CIS may be useful in predicting conversion to CDMS within the following 2 years of the disease course., (Copyright © 2021 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.)

Background and Purpose: This study's aim was to investigate diffusion properties of the cervical spinal cord in patients with clinically isolated syndrome (CIS) through analysis of diffusion tensor imaging (DTI) data and thereby to assess the capacity of this technique for predicting the progression of CIS to clinically definite multiple sclerosis (CDMS)., Methods: The study groups were comprised of 47 patients with CIS (15 of them with progression to CDMS within 2 years of follow-up) and 57 asymptomatic controls. All patients and controls had undergone magnetic resonance imaging (MRI) of the cervical spine including DTI and brain MRI. Methodological approaches included histogram analysis of the cervical cord's diffusion parameters and evaluation of T2 hyperintense lesions of the spinal cord and brain. All parameters were compared between the study groups. Sensitivity and specificity calculations were then performed with a view to predicting conversion to CDMS., Results: The patient subgroups defined by progression to CDMS differed significantly in values of fractional anisotropy (FA) kurtosis measured within white matter (WM) and normal-appearing WM (NAWM). The same parameters also differed significantly when patients with progression to CDMS were compared to healthy controls. Receiver operating characteristic (ROC) analysis revealed sensitivity and specificity of FA kurtosis of WM and NAWM of 93% and 72%, respectively, in terms of predicting CIS to CDMS progression., Conclusion: This study presents evidence that histogram analysis of diffusion parameters of the cervical spinal cord in patients with CIS may be helpful in predicting conversion to CDMS., (© 2020 American Society of Neuroimaging.)

Background: Multiple sclerosis (MS) begins with an acute clinical attack (clinically isolated syndrome) in approximately 85% of patients. The conversion rate from clinically isolated syndrome to multiple sclerosis has been documented at 30% to 82% in previous studies. When an individual presents for evaluation after a single episode of inflammation of the CNS, several decisions regarding follow-up in subsequent years need to be made, including that of whether or not to start a therapy. There is, therefore, an emerging need to identify the predictive factors that anticipate conversion from CIS to MS., Methods: This paper presents a single-center prospective longitudinal study aimed at identification of the most powerful independent predictors for conversion from CIS to MS, utilizing the 2010 McDonald MS criteria and focusing on selected demographic, clinical, radiographical (magnetic resonance imaging - MRI), cerebrospinal fluid (predominantly oligoclonal bands - OCB) and electrophysiological parameters (multimodal sensory and motor-evoked potentials - EP). Two independent outcomes meeting MS criteria are evaluated: development of second clinical relapse (clinically definite multiple sclerosis) and progression in magnetic resonance imaging (based on new MRI T2 brain and/or spinal cord lesions). CIS patients were followed clinically and MRI was repeated at one and two years within the course of a follow-up period of at least 24 months (median 27, range 24-36 months)., Results: Of the 64 CIS patients enrolled who completed at least a 2-year follow-up period (42 women and 22 men, median age 36.5, range 22-66 years), 45 (70.3%) (29 women and 16 men, median age 38; range 22-66 years) fulfilled the 2010 McDonald criteria for MS by dissemination in space (DIS) and time (DIT) over the follow-up period. Twenty-nine CIS patients converted to MS through a clinically symptomatic attack, and 16 CIS patients developed new T2 lesions on MRI, while 19 patients without progression remained stable as CIS. Confirmed among potential predictors for the conversion of CIS patients to MS were increased (>10) baseline MRI T2-hyperintense lesions (odds ratio (OR) 3.107, p = 0.046), OCB positivity (OR 5.958, p = 0.003) and subclinical EP abnormality (OR 14.400, p = 0.003). Multivariate statistical models (logistic regression and Cox proportional hazards regression models) confirmed these parameters as independent predictors of high sensitivity (84%) and acceptable specificity (63%)., Conclusion: In addition to accepted predictors for the conversion of CIS to MS (i.e. baseline MRI T2 lesion load and OCB positivity), already implemented in current diagnostic criteria for MS, this study demonstrates, in addition, the high predictive value of subclinical multimodal evoked potential abnormalities., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Objectives: Although white matter hyperintensities (WMHs) are quite commonly found incidentally, their aetiology, structural characteristics, and functional consequences are not entirely known. The purpose of this study was to quantify WMHs in a sample of young, neurologically asymptomatic adults and evaluate the structural and functional correlations of lesion load with changes in brain volume, diffusivity, and functional connectivity., Methods: MRI brain scan using multimodal protocol was performed in 60 neurologically asymptomatic volunteers (21 men, 39 women, mean age 34.5 years). WMHs were manually segmented in 3D FLAIR images and counted automatically. The number and volume of WMHs were correlated with brain volume, resting-state functional MRI (rs-fMRI), and diffusion tensor imaging (DTI) data. Diffusion parameters measured within WMHs and normally appearing white matter (NAWM) were compared., Results: At least 1 lesion was found in 40 (67%) subjects, median incidence was 1 lesion (interquartile range [IQR] = 4.5), and median volume was 86.82 (IQR = 227.23) mm 3 . Neither number nor volume of WMHs correlated significantly with total brain volume or volumes of white and grey matter. Mean diffusivity values within WMHs were significantly higher compared with those for NAWM, but none of the diffusion parameters of NAWM were significantly correlated with WMH load. Both the number and volume of WMHs were correlated with the changes of functional connectivity between several regions of the brain, mostly decreased connectivity of the cerebellum., Conclusions: WMHs are commonly found even in young, neurologically asymptomatic adults. Their presence is not associated with brain atrophy or global changes of diffusivity, but the increasing number and volume of these lesions correlate with changes of brain connectivity, and especially that of the cerebellum., Key Points: • White matter hyperintensities (WMHs) are commonly found in young, neurologically asymptomatic adults. • The presence of WMHs is not associated with brain atrophy or global changes of white matter diffusivity. • The increasing number and volume of WMHs correlate with changes of brain connectivity, and especially with that of the cerebellum.

Although the role of high-risk human papillomaviruses (hrHPVs) as etiological agents in cancer development has been intensively studied during the last decades, there is still the necessity of understanding the impact of the HPV E6 and E7 oncogenes on host cells, ultimately leading to malignant transformation. Here, we used newly established immortalized human keratinocytes with a well-defined HPV16 E6E7 expression cassette to get a more complete and less biased overview of global changes induced by HPV16 by employing transcriptome sequencing (RNA-Seq) and stable isotope labeling by amino acids in cell culture (SILAC). This is the first study combining transcriptome and proteome data to characterize the impact of HPV oncogenes in human keratinocytes in comparison with their virus-negative counterparts. To enhance the informative value and accuracy of the RNA-Seq data, four different bioinformatic workflows were used. We identified potential novel upstream regulators (e.g., CNOT7, SPDEF, MITF, and PAX5) controlling distinct clusters of genes within the HPV-host cell network as well as distinct factors (e.g., CPPED1, LCP1, and TAGLN) with essential functions in cancer. Validated results in this study were compared to data sets from The Cancer Genome Atlas (TCGA), demonstrating that several identified factors were also differentially expressed in cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) and HPV-positive head and neck squamous cell carcinomas (HNSCs). This highly integrative approach allows the identification of novel HPV-induced cellular changes that are also reflected in cancer patients, providing a promising omics data set for future studies in both basic and translational research. IMPORTANCE Human papillomavirus (HPV)-associated cancers still remain a big health problem, especially in developing countries, despite the availability of prophylactic vaccines. Although HPV oncogenes have been intensively investigated for decades, a study applying recent advances in RNA-Seq and quantitative proteomic approaches to a precancerous model system with well-defined HPV oncogene expression alongside HPV-negative parental cells has been missing until now. Here, combined omics analyses reveal global changes caused by the viral oncogenes in a less biased way and allow the identification of novel factors and key cellular networks potentially promoting malignant transformation. In addition, this system also provides a basis for mechanistic research on novel key factors regulated by HPV oncogenes, especially those that are confirmed in vivo in cervical cancer as well as in head and neck cancer patient samples from TCGA data sets., (Copyright © 2019 Yang et al.)

Tularemia, otherwise known as “rabbit fever”, is a zoonotic disease caused by a gram-negative intracellular bacterium - Francisella tularensis. The species is considered as a potential bioterrorism agent due to its high infectivity, the fact of being relatively easy to culture, the absence of human vaccine, and the potential for spreading through aerosol. In the Czech Republic, infection is usually caused by a tick bite, less frequently by a mosquito bite, direct contact with infected animals, or ingestion of contaminated water. The aim of this review is to provide a comprehensive view of tularemia, its diagnosis, clinical symptoms and treatment, along with the military perspective on a potential risk of F. tularensis to be misused as a biological weapon.

Background: Segmentation of the gray and white matter (GM, WM) of the human spinal cord in MRI images as well as the analysis of spinal cord diffusivity are challenging. When appropriately segmented, diffusion tensor imaging (DTI) of the spinal cord might be beneficial in the diagnosis and prognosis of several diseases., Purpose: To evaluate the applicability of a semiautomatic algorithm provided by ITK-SNAP in classification mode (CLASS) for segmenting cervical spinal cord GM, WM in MRI images and analyzing DTI parameters., Study Type: Prospective., Subjects: Twenty healthy volunteers., Sequences: 1.5T, turbo spin echo, fast field echo, single-shot echo planar imaging., Assessment: Three raters segmented the tissues by manual, CLASS, and atlas-based methods (Spinal Cord Toolbox, SCT) on T 2 -weighted and DTI images. Masks were quantified by similarity and distance metrics, then analyzed for repeatability and mutual comparability. Masks created over T 2 images were registered into diffusion space and fractional anisotropy (FA) values were statistically evaluated for dependency on method, rater, or tissue. STATISTICAL TESTS: t-test, analysis of variance (ANOVA), coefficient of variation, Dice coefficient, Hausdorff distance., Results: CLASS segmentation reached better agreement with manual segmentation than did SCT (P < 0.001). Intra- and interobserver repeatability of SCT was better for GM and WM (both P < 0.001) but comparable with CLASS in entire spinal cord segmentation (P = 0.17 and P = 0.07, respectively). While FA values of whole spinal cord were not influenced by choice of segmentation method, both semiautomatic methods yielded lower FA values (P < 0.005) for GM than did the manual technique (mean differences 0.02 and 0.04 for SCT and CLASS, respectively). Repeatability of FA values for all methods was sufficient, with mostly less than 2% variance., Data Conclusion: The presented semiautomatic method in combination with the proposed approach to data registration and analyses of spinal cord diffusivity can potentially be used as an alternative to atlas-based segmentation., Level of Evidence: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:1217-1227., (© 2018 International Society for Magnetic Resonance in Medicine.)

The adenylate cyclase toxin (CyaA) of the whooping cough agent Bordetella pertussis subverts immune functions of host myeloid cells expressing the α M β 2 integrin (CD11b/CD18, CR3 or Mac-1). CyaA delivers into cytosol of cells an extremely catalytically active adenylyl cyclase enzyme, which disrupts the innate and adaptive immune functions of phagocytes through unregulated production of the key signaling molecule cAMP. We have used phosphoproteomics to analyze cAMP signaling of CyaA in murine bone marrow-derived dendritic cells. CyaA action resulted in alterations of phosphorylation state of a number of proteins that regulate actin cytoskeleton homeostasis, including Mena, Talin-1 and VASP. CyaA action repressed mTOR signaling through activation of mTORC1 inhibitors TSC2 and PRAS40 and altered phosphorylation of multiple chromatin remodelers, including the class II histone deacetylase HDAC5. CyaA toxin action further elicited inhibitory phosphorylation of SIK family kinases involved in modulation of immune response and provoked dephosphorylation of the transcriptional coactivator CRTC3, indicating that CyaA-promoted nuclear translocation of CRTC3 may account for CyaA-induced IL-10 production. These findings document the complexity of subversive physiological manipulation of myeloid phagocytes by the CyaA toxin, serving in immune evasion of the pertussis agent.

The success of pathogens depends on their ability to circumvent immune defences. Francisella tularensis is one of the most infectious bacteria known. The remarkable virulence of Francisella is believed to be due to its capacity to evade or subvert the immune system, but how remains obscure. Here, we show that Francisella triggers but concomitantly inhibits the Toll-like receptor, RIG-I-like receptor, and cytoplasmic DNA pathways. Francisella subverts these pathways at least in part by inhibiting K63-linked polyubiquitination and assembly of TRAF6 and TRAF3 complexes that control the transcriptional responses of pattern recognition receptors. We show that this mode of inhibition requires a functional type VI secretion system and/or the presence of live bacteria in the cytoplasm. The ability of Francisella to enter the cytosol while simultaneously inhibiting multiple pattern recognition receptor pathways may account for the notable capacity of this bacterium to invade and proliferate in the host without evoking a self-limiting innate immune response., (© 2017 John Wiley & Sons Ltd.)

The initiation of T-cell signaling is critically dependent on the function of the member of Src family tyrosine kinases, Lck. Upon T-cell antigen receptor (TCR) triggering, Lck kinase activity induces the nucleation of signal-transducing hubs that regulate the formation of complex signaling network and cytoskeletal rearrangement. In addition, the delivery of Lck function requires rapid and targeted membrane redistribution, but the mechanism underpinning this process is largely unknown. To gain insight into this process, we considered previously described proteins that could assist in this process via their capacity to interact with kinases and regulate their intracellular translocations. An adaptor protein, receptor for activated C kinase 1 (RACK1), was chosen as a viable option, and its capacity to bind Lck and aid the process of activation-induced redistribution of Lck was assessed. Our microscopic observation showed that T-cell activation induces a rapid, concomitant, and transient co-redistribution of Lck and RACK1 into the forming immunological synapse. Consistent with this observation, the formation of transient RACK1-Lck complexes were detectable in primary CD4 + T-cells with their maximum levels peaking 10 s after TCR-CD4 co-aggregation. Moreover, RACK1 preferentially binds to a pool of kinase active pY394 Lck , which co-purifies with high molecular weight cellular fractions. The formation of RACK1-Lck complexes depends on functional SH2 and SH3 domains of Lck and includes several other signaling and cytoskeletal elements that transiently bind the complex. Notably, the F-actin-crosslinking protein, α-actinin-1, binds to RACK1 only in the presence of kinase active Lck suggesting that the formation of RACK1-pY394 Lck -α-actinin-1 complex serves as a signal module coupling actin cytoskeleton bundling with productive TCR/CD4 triggering. In addition, the treatment of CD4 + T-cells with nocodazole, which disrupts the microtubular network, also blocked the formation of RACK1-Lck complexes. Importantly, activation-induced Lck redistribution was diminished in primary CD4 + T-cells by an adenoviral-mediated knockdown of RACK1. These results demonstrate that in T cells, RACK1, as an essential component of the multiprotein complex which upon TCR engagement, links the binding of kinase active Lck to elements of the cytoskeletal network and affects the subcellular redistribution of Lck.

Background: Amyloidosis is a disease characterized by deposits of abnormal protein known as amyloid in various organs and tissues. It can be classified into systemic or localized forms, the latter of which is less frequent. Deposition of amyloidogenic monoclonal light chains leads to the most common type of this disease called light-chain (AL) amyloidosis. (18)F-FDG positron emission tomography/ computed tomography hybrid imaging (FDG-PET/ CT) demonstrates tracer uptake usually in all patients with localized amyloidosis as opposed to the systemic form., Case: Herein, we present a case of an otherwise healthy 56-year-old women diagnosed with a nasal polyp on the right side. The biopsy results were consistent with amyloidosis. FDG-PET/ CT imaging revealed a pathological, metabolically active lesion measuring 11 × 9 mm with a maximum standardized uptake value (SUV(max)) of 3.47. No other distant pathological changes were identified. After a radical resection, the patient has been regularly followed-up with clinical and imaging methods (MRI, FDG-PET/ CT), both of which repeatedly showed normal findings with disease-free survival of 27 months. Thus, FDG-PET/ CT imaging plays an important role not only for obtaining the right diagnosis but also in the follow-up of patients after surgical resection. In accordance with the literature, this case report confirms that FDG-PET/ CT imaging holds promise as an auxiliary method for distinguishing between localized and systemic forms of amyloidosis.

Due to their cardiac origin, H9c2 cells rank among the most popular cell lines in current cardiovascular research, yet molecular phenotype remains elusive. Hence, in this study we used proteomic approach to describe molecular phenotype of H9c2 cells in their undifferentiated (i.e., most frequently used) state, and its functional response to cardiotoxic drug doxorubicin. Of 1671 proteins identified by iTRAQ IEF/LC-MSMS analysis, only 12 proteins were characteristic for striated muscle cells and none was cardiac phenotype-specific. Targeted LC-SRM and western blot analyses confirmed that undifferentiated H9c2 cells are phenotypically considerably different to both primary neonatal cardiomyocytes and adult myocardium. These cells lack proteins essential for formation of striated muscle myofibrils or they express only minor amounts thereof. They also fail to express many proteins important for metabolism of muscle cells. The challenge with clinically relevant concentrations of doxorubicin did not induce a proteomic signature that has been previously noted in primary cardiomyocytes or adult hearts. Instead, several alterations previously described in other cells of mesodermal origin, such as fibroblasts, were observed (e.g., severe down-regulation of collagen synthesis pathway). In conclusion, the molecular phenotype of H9c2 cells resembles very immature myogenic cells with skeletal muscle commitment upon differentiation and thus, translatability of findings obtained in these cells deserves caution., (Copyright © 2015 Elsevier Inc. All rights reserved.)

This article describes a case of 68-years-old male with very atypic variation of multiple myeloma occuring as multifocal osteolysis limited to tibiae, cuboid bone, radius and ulna, in the absence of diffuse bone marrow infiltration. The main goal of this article is to point out the importance of permanent awareness during diagnostics and treatment of this insidious disease.

Outer membrane vesicles secreted by gram-negative bacteria play an important role in bacterial physiology as well as in virulence and host-pathogen interaction. Isolated vesicles of some bacteria have also been studied for their immunomodulatory potential in the vaccine development. However, the production of vesicles in sufficient amount, purity and reproducibility remains a critical challenge for subsequent analyses in most bacteria. In the present review methods of production, isolation, purification and quantification of outer membrane vesicles are summarized and discussed., (Copyright © 2014 Elsevier GmbH. All rights reserved.)

Purpose of the Study: The aim of this prospective study was to evaluate clinical and radiographic results in the patients who underwent L5-S1 fixation using the technique of percutaneous lumbar interbody fusion (AxiaLIF)., Material: The study comprised 23 patients, 11 women and 12 men, who ranged from age of 21 to 63 years, with an average of 48.2 years. In all patients surgical posterior stabilisation involving the L5-S1 segment had previously been done. The initial indications for surgery were L5-S1 spondylolisthesis in 20 and L5-S1 spondylosis and stenosis in three patients., Methods: The AxiaLIF technique for L5-S1 fixation was indicated in overweight patients and in those after repeated abdominal or retroperitoneal surgery. A suitable position and shape of the sacrum or lumbosacral junction was another criterion. The patients were evaluated between 26 and 56 months (average, 40.4 months) after primary surgery and, on the basis of CT and radiographic findings, bone union and lumbosacral junction stability were assessed. The clinical outcome was investigated using the ODI and VAS systems and the results were statistically analysed by the Wilcoxon test for paired samples with statistical significance set at a level of 0.05., Results: The average VAS value was 6.6 before surgery and, after surgery, 5.2 at three months, 4.2 at six months, 3.1 at one year, 2.9 at two years and 2.1 at three years (n=18). At two post-operative years, improvement in the VAS value by 56.1% was recorded. The average pre-operative ODI value was 25.1; the post-operative values were 17.0 at six months, 12.3 at one year, 10.6 at two years and 8.2 at three years (n=18). At two years after surgery the ODI value improved by 57.8%. To the question concerning their willingness to undergo, with acquired experience, surgery for the same diagnosis, 21 patients (91.3%) gave an affirmative answer. Neither screw breakage nor neurovascular damage or rectal injury was found. CT scans showed complete interbody bone fusion in 22 of the 23 patients (95.6%), In one patient the finding was not clear. Also, posterolateral fusion was achieved in all but one patients (95.6%). A stable L5-S1 segment was found in all patients at all follow-up intervals. The improvement in both VAS and ODI values was statistically significant., Discussion: In addition to indications usual in degenerative disc disease, overweight patients, those who had repeated trans- or retroperitoneal surgery in the L5-S1 region or who underwent long posterior fixation to stabilise the caudal margin of instrumentation are indicated for the AxiaLIF procedure. The clinical results of our study are in agreement with the conclusions of other studies and are similar to the outcomes of surgery using other types of fusion or dynamic stabilisation for this diagnosis. The high rate of fusion in our group is affected by use of a rigid transpedicular fixator together with posterolateral arthrodesis. On the other hand, no negative effects of only synthetic bone applied to interbody space were recorded., Conclusions: The percutaneous axial pre-sacral approach to the L5-S1 interbody space with application of a double-treaded screw is another option for the management of this much strained segment. The technique is useful particularly when contraindications for conventional surgical procedures are present in patients with anatomical anomalies, in overweight patients or in those who have had repeated surgery in the region. Clinical outcomes and the success rate for L5-S1 bone fusion are comparable with conventional techniques. Complications are rare but their treatment is difficult.

The intracellular pathogens have the unique capacity to sense the host cell environment and to respond to it by alteration in gene expression and protein synthesis. Proteomic analysis of bacteria exposed directly to the host cell milieu might thus greatly contribute to the elucidation of processes leading to bacterial adaptation and proliferation inside the host cell. Here we have performed a global proteome analysis of a virulent Francisella tularensis subsp. holarctica strain during its intracellular cycle within the macrophage-like murine cell line J774.2 using the metabolic pulse-labeling of bacterial proteins with (35)S-methionine and (35)S-cysteine in various periods of infection. The two-dimensional gel analysis revealed macrophage-induced bacterial proteome changes in which 64 identified proteins were differentially expressed in comparison to controls grown in tissue culture medium. Nevertheless, activation of macrophages with interferon gamma before in vitro infection decreased the number of detected alterations in protein levels. Thus, these proteomic data indicate the F. tularensis ability to adapt to the intracellular hostile environment that is, however, diminished by prior interferon gamma treatment of host cells.

Determining disease-associated changes in protein glycosylation provides a better understanding of pathogenesis. This work focuses on human immunoglobulin A1 (IgA1), where aberrant O-glycosylation plays a key role in the pathogenesis of IgA nephropathy (IgAN). Normal IgA1 hinge region carries 3 to 6 O-glycans consisting of N-acetylgalactosamine (GalNAc) and galactose (Gal); both sugars may be sialylated. In IgAN patients, some O-glycans on a fraction of IgA1 molecules are Gal-deficient. Here we describe a sample preparation protocol with optimized cysteine alkylation of a Gal-deficient polymeric IgA1 myeloma protein prior to in-gel digestion and analysis of the digest by MALDI-TOF/TOF mass spectrometry (MS). Following a novel strategy, IgA1 hinge-region O-glycopeptides were fractionated by reversed-phase liquid chromatography using a microgradient device and identified by MALDI-TOF/TOF tandem MS (MS/MS). The acquired MS/MS spectra were interpreted manually and by means of our own software. This allowed assigning up to six O-glycosylation sites and demonstration, for the first time, of the distribution of isomeric O-glycoforms having the same molecular mass, but a different glycosylation pattern. The most abundant Gal-deficient O-glycoforms were GalNAc4Gal3 and GalNAc5Gal4 with one Gal-deficient site and GalNAc5Gal3 and GalNAc4Gal2 with two Gal-deficient sites. The most frequent Gal-deficient sites were at Ser230 and/or Thr236., Biological Significance: In this work, we studied the O-glycosylation in the hinge region of human immunoglobulin A1 (IgA1). Aberrant glycosylation of the protein plays a key role in the pathogenesis of IgA nephropathy. Thus identification of the O-glycan composition of IgA1 is important for a deeper understanding of the disease mechanism, biomarker discovery and validation, and implementation and monitoring of disease-specific therapies. We developed a new procedure for elucidating the heterogeneity of IgA1 O-glycosylation. After running a polyacrylamide gel electrophoresis under denaturing conditions, the heavy chain of IgA1 was subjected to in-gel digestion by trypsin. O-glycopeptides were separated from the digest on capillary columns using a microgradient chromatographic device (replacing commonly used liquid chromatographs) and subjected to MALDI-TOF/TOF mass spectrometry (MS) and tandem mass spectrometry (MS/MS) involving post-source decay fragmentation. We show that the complete modification of cysteines by iodoacetamide prior to electrophoresis is critical for successful MS/MS analyses on the way to deciphering the microheterogeneity of O-glycosylation in IgA1. Similarly, the removal of the excess of the reagent is equally important. The acquired MS/MS allowed assigning up to six O-glycosylation sites and identification of isomeric O-glycoforms. We show that our simplified approach is efficient and has a high potential to provide a method for the rapid assessment of IgA1 heterogeneity that is a less expensive and yet corroborating alternative to LC-(high-resolution)-MS protocols. The novelty and biological significance reside in the demonstration, for the first time, of the distribution of the most abundant isoforms of HR O-glycopeptides of IgA1. As another new feature, we introduce a software solution for the interpretation of MS/MS data of O-glycopeptide isoforms, which provides the possibility of fast and easier data processing. This article is part of a Special Issue entitled: Posttranslational Protein modifications in biology and Medicine., (© 2013 Elsevier B.V. All rights reserved.)

Purpose of the Study: Injuries to the upper cervical spine in children are rare and account for 0.6 to 9.5% of all cervical spine injuries. We present a detailed analysis of the children and adolescents with unstable upper cervical spine injuries treated at our spinal centre., Material: During 16 years of follow-up, unstable injury to the upper cervical spine was recorded in 23 children and adolescents. Two patients (8.7%) were treated conservatively and 21 (91.3%) underwent surgery. The patients were allocated by age to three groups: 0-9 year, 10-14 year and 15-18 year categories. Twenty patients were seen at the final clinical and radiographic follow-up. One patient died at 62 months after surgery and two patients unfit for transport were evaluated on the basis of mailed interviews. The interval between injury and final evaluation ranged from 6 to 137 months, with an average of 53.4 months., Methods: The patients treated conservatively first wore a Philadelphia collar, then a custom-made brace, and eventually a soft Schanze cervical collar to finish the healing process. Application of a halo vest was considered a surgical procedure and was used only in very small children. In unstable odontoid fractures, direct osteosynthesis with two cannulated titanium screws was performed from the anterior approach in older children while, in small children, transoral or submandibular retropharyngeal decompression to treat spinal stenosis caused by bone fragments was carried out and a halo vest was applied. Hangman's fractures were treated by anterior cervical discectomy, fusion with bone graft and anterior plate fixation. The other types of unstable fractures were managed from the posterior approach by occipitocervical fixation, atlantoaxial fixation or instrumented fusion extended caudally. The patients characteristics included gender, age, mechanism of injury, type of injury, neurological findings, type of therapy or surgery, complications and treatment outcome. Neurological status was evaluated using the Frankel classification., Results: The patient group comprised 14 boys (60.9%) and nine girls (39.1%), which gave a gender ratio of 3 : 2. The age of patients at injury ranged from 2 to 18 years, with an average of 11 years and 6 months. The most frequent injuries included rotational or vertical atlantoaxial dislocation in eight (34.8%) and odontoid fractures in seven (30.4%) patients; atlas fracture was recorded in three (13.0%) and hangman's fracture also in three (13.0%) patients; occipitocervical displacement was found in one (4.3%) and complex atlantoaxial fracture also in one patient (4.3%). At the time of injury, 17 patients (73.9%) had no neurological deficit (Frankel grade E), three had Frankel grade A (one paraplegic with a concomitant T5 spinal cord injury) and three had Frankel grade D neurological deficits. Of the six patients with neurological deficit, two showed improvement by one or two Frankel grades. The method of dorsal atlantoaxial fixation was used in eight patients (Magerl fixation in 2 and Harms method in 6). Direct osteosynthesis of an odontoid fracture was performed in four patients, halo fixation was applied in four, C2-C3 discectomy with tricortical bone grafting and plating was carried out in three, occipitocervical fixation was used in three patients, and direct atlas osteosynthesis, simple decompression and simple non-instrumented dorsal spondylodesis each was performed in one patient. Neither intra-operative complications nor post-operative complications related to the surgical technique were recorded. Osteoarthritis or bone non-union, as late post-operative complications, were found in two patients. All other patients showed bone healing by first intention in the desired extent. Superficial or deep wound infections were not recorded., Discussion: In the first age category, the number of boys and girls with injuries to the upper cervical spine was equal while, in the third one, the boys outnumbered the girls more than twice. Of the 23 patients, 91.3% were surgically treated; the anterior approach was used in approximately one third of the patients and the posterior approach in the rest of them. The high number of surgical interventions is due to the fact that the most serious paediatric spinal injuries are referred to our centre., Conclusions: 1. Injuries to the upper cervical spine are most frequently found in the youngest children and in adolescents who, however, frequently have injury also to the lower cervical spine. 2. Neurological deficit is relatively frequent but has a better prognosis than in adults. The youngest children with mild deficits have the best prognosis. 3. The mortality rate in young children with upper cervical spine injuries is evidently high, mostly due to associated head, chest and abdomen trauma 4. Therapy, particularly in small children, is strictly individual.

The field of microbial proteomics has currently experienced a boom in the discovery of glycosylated proteins of various pathogenic bacteria as potential mediators of host-pathogen interactions. The presence of glycoproteins has recently been discovered in a Gram-negative pathogenic bacterium Francisella tularensis , utilizing glycoprotein detection and isolation techniques in combination with mass spectrometry. The isolation of glycoproteins is a prerequisite for their subsequent mass-spectrometric identification. Current glycoprotein isolation/enrichment methods comprise lectin affinity chromatography, aminophenylboronic acid and hydrazide-based enrichment. The use of magnetic microspheres containing functional groups is nowadays among state-of-art separation methodologies owing to an ease of manipulation, a speed of separation, and a minimum of non-specific protein adsorption. In the present study, novel magnetic hydrazide-modified poly(2-hydroxyethyl methacrylate) (PHEMA) microspheres were developed using a multi-step swelling and polymerization method with subsequent precipitation of magnetic iron oxides within the pores of the particles. The microspheres had a regular shape, size of 4 μm and contained 0.18 mmol hydrazide groups per g; the magnetic microspheres were employed for specific enrichment of Francisella tularensis glycoproteins. Effectiveness of the newly prepared magnetic microspheres for glycoprotein enrichment was proved by comparison with commercial hydrazide-functionalized microparticles.

Purpose of the Study: Atlantoaxial osteoarthritis (AAOA) is a clinical syndrome with signs distinctly different from those of degenerative sub - axial spine disease. Its diagnosis may long be delayed, partly because of insufficient knowledge and partly due to difficulties in interpreting both anteroposterior and lateral radiographs. The aim of this prospective study was to evaluate the first 27 AAOA patients treated at our department., Material: From 2001 we performed atlantoaxial fixation with fusion in a total of 29 patients with painful arthritis of the atlanto axial complex. The 27 patients treated before the end of 2010 were enrolled in the study and analysed in detail. This group included 13 women and 14 men aged between 35 and 72 years, with an average age of 53.5 years. In all patients atlanto - axial fixation was performed using the polyaxial screw-rod system according to Harms., Methods: The patients were followed up at 6 and 12 weeks, 6 and 12 months and then once a year after surgery. X-ray examinations were done at the same intervals as clinical examinations; functional radiographs were made at 12 to 14 weeks after surgery. The definitive analysis of the group was made in the range of 4 to 59 months (average, 25.7 months) after the primary operation. Patients' subjective evaluation was based on NPDI and VAS scores and a question of whether the patient would undergo the surgery again. Objective evaluation included clinical outcomes - pain and neurological findings; radiographic results - stability and healing of C1-C2 fusion; and complications during surgery and in early and late postoperative periods. As intra-operative complications were regarded those associated with the surgical approach, nerve injury and vertebral artery injury. Early post-operative complications included poor wound healing and changes in the patient's neurological status, late complications included instrumentation failure and infection. Patients' clinical status (NPDI, VAS) was statistically evaluated using the one-way ANOVA., Results: The mean VAS score was pre-operatively 7.0 and post-operatively 5.6 at 3 months, 5.0 at 6 months, 5.1 at 1 year; 3.9 at 2 years and 4.0 at 3 years. The mean NPDI value was pre-operatively 39.6 and post-operatively 38.7 at 3 months, 36.0 at 6 months, 34.5 at 1 year, 34.3 at 2 years and 33.1 at 3 years. The question of willingness to undergo the same operation again was answered in the affirmative by 21 patients (77.8%), in the negative by five (18.5%) and one patient did not know (3.7%). Complete bone fusion, as assessed by radiography or CT scanning, was achieved in 26 out of 27 patients (96.3%). In one patient the result was ambiguous but, at 3 months as well as the next follow-ups, C1-C2 complex stability was found., Discussion: All patients in our group underwent a unified system of clinical, radiological, CT and MRI examination. In the decision-making process, emphasis was placed on a correlation of clinical findings with CT scanning results. All patients were operated on from the posterior approach using the Harms method, and radiological outcomes were similar to those of Grob et al. who used the Magerl's technique of C1-C2 fixation. The VAS and NPDI scores demonstrated significant improvement as early as 3 post-operative months, with still further improvement in the following period. The stable clinical status of the patients was achieved at 2 years after surgery. From the practical standpoint we were interested in an answer to the question of whether the patients would be willing to undergo the procedure again. Almost 80% of affirmative answers testified to the correct choice of treatment. The values found corresponded to those reported by Grob at al., Conclusions: Patients with painful osteoarthritis refractory to conservative treatment will benefit from atlantoaxial fixation and fusion. For the patient, restricted cervical rotation is acceptable in return for pain relief. From the surgical point of view, the risk of complications associated with the operative technique did not exceed a tolerable rate.

We present the case of a patient, aged 4 years and 10 months, with metatropic dysplasia. The baby had repeated apnoeic episodes, bradycardia and cardiac arrests and was diagnosed with foramen magnum stenosis and atlantodental dislocation. The episodes were markedly associated with neck movements. Considering this clinical presentation, we performed laminectomy of the atlas, foramen magnum enlargement and decompression followed by dorsal C0-C2 stabilisa - tion with allogeneic bone chips. After the operation, apnoeic episodes did not recur.

Purpose of the Study: Spinal cord concussion is characterised as fully reversible, temporary inhibition of conductive function due to trauma, without signs of structural changes. Although neurological deficit is usually related to the severity of spinal injury, this is different in spinal cord concussion. The aim of this retrospective study was to evaluate a group of 24 patients with spinal cord concussion, to design a diagnostic algorithm and propose an effective therapy with a good prognosis for the patients., Material: We reviewed clinical records of 9 768 patients hospitalised at the Department of Spinal Surgery, University Hospital in Motol, from September 2002 till December 2010, and of 457 patients treated at other departments of the Hospital between January 2008 and December 2010; this was a total of 10 225 patients. The data were retrospectively analysed and only the patients with a clear history of trauma and subsequent conservative therapy were selected to comprise a group characterised by the generally known criteria of spinal cord concussion: (1) spinal injury with immediate neurological deficit of varying degree; (2) neurological deficit corresponding to the level of spinal injury; (3) recovery of neurological function within 72 hours of injury; (4) no morphological evidence of injury to the spinal structures obtained by imaging methods. This group comprised 24 patients., Methods: The patients were followed up from 6 to 95 months, with a mean of 46 months and a median of 48 months, at intervals of 6 and 12 weeks and 6 and 12 months after injury, and then every following year. The recorded information included the patient's age at the time of injury, their gender, the mechanism of injury, reports on alcohol consumption, the first detected neurological deficit, its development immediately after injury, during the hospital stay and at follow-ups in the out-patient department, methylprednisolone administration according to the National Acute Spinal Cord Injury Study (NASCIS) 2, and findings of imaging methods, particularly MRI., Results: Our group consisted of 22 men (91.7%) and two women (8.3%), with an average age of 29 years; the average age was 30 years in men and 18.5 years in women. Seven patients (29.2%) were younger than 18 years, with an average of 16.14 years; the remaining 17 patients (70.8%) were older than 18 years, with an average of 34.35 years. The major mechanisms of injury included falls from a height in 10 patients (41.7%) and injury due to alcohol consumption in five patients (20.1%). Clinical findings involved lesions of the medullary cone in 12 (50.0%), cervical spinal cord in seven (29.2%) and thoracic spinal cord in five (20.8%) patients. Motor function deficit was present in all patients, of whom 10 (41.2%) showed a complete loss of motor function. Impaired sensory function was found in 21 (87.5%) patients. One patient had perianal and genital sensory deficit and one (4.2%) had urinary retention. Neither radiograms nor CT scans showed traumatic changes in any of the patients; MRI findings free of any traumatic spinal changes were recorded in 21 patients (87.5%). One patient had oedema of the T5 and T8 vertebral bodies. No complications were recorded. All patients experienced rapid resolution of neurological deficit, which occurred within 6 hours of injury in two (8.4%), within 12 hours in two (8.4%), within 24 hours in 12 (50.0%) and within 48 hours in six (25.0%) patients, and later than 48 hours after injury in two patients (8.4%). However, recovery always occurred within 72 hours of injury., Discussion: A good prognosis for patients with this injury is supported by our findings, because all patients experienced rapid resolution of neurological deficit within 72 hours of injury. This result is in agreement with the relevant international studies reporting no serious complications associated with spinal trauma. There are no clear recommendations for administration of high doses of methylprednisolone according to the NASCIS system., Conclusions: Spinal cord concussion is not a frequent injury; in our study, it accounted for 3.54% of the patients with trauma histories out of the total number of 678 patients, or for 2.40% out of 997 injured spinal levels. The first steps should be the same as in any other injury to the spinal cord. An early examination of the patient with imaging methods including MRI is of primary importance. At present administration of methylprednisolone according to the NASCIS system is disputable. The patient diagnosed with spinal cord concussion has a good prognosis, with rehabilitation as the main therapeutic approach.

Purpose of the Study: To present the results of an independent prospective monocentric study of patients with ProDisc-C Total Disc Replacement (CTDR) followed up for 4 years, and to analyse the most frequent late complications, in particular heterotopic ossification., Material: In the period from October 2004 to May 2006, a total of 61 patients underwent ProDisc-C CTDR involving one or two segments at the Department of Spinal Surgery, University Hospital in Motol. This study included 39 patients who were followed up for at least 4 years. With the exception of one patient operated on two segments, the patients were treated by ProDisc-C CTDR at one level., Methods: In the study, only the surgical procedure recommended by the implant manufacturer (Synthes, USA) was used and all operations were performed by a team with the same leading surgeon. Clinical assessment. The patients were examined before surgery, immediately after it and at 6 and 12 weeks and 6, 12, 24 and 48 months post-operatively. At each follow-up, responses to the questionnaire were obtained, and the patients' health status was evaluated on the basis of Neck Disability Index (NDI) and Visual Analogue Score (VAS) values for cervical spine and radicular pain, the use of analgesics and personal satisfaction Radiographic assessment. Pre- and post-operative radiographs were taken in antero-posterior and lateral projection, and flexion, extension and lateral bending films were obtained The height of the intervertebral disc space at the affected level was measured and range of motion in flexion and extension was evaluated together with the adjacent levels. In addition, subsidence, loosening, failure or displacement of the implant was assessed, as well as the presence of heterotopic ossification. The results were statistically analysed using Student's t-test., Results: The clinical results at 1, 2 and 4 years of follow-up were as follows: NDI values, 44.9 pre-operatively, 26.1, 25.8 and 25.1 post-operatively, improvement by 44.1% after 4 years; VAS for cervical spine pain, 5.8 pre-operatively, 3.0, 2.7 and 2.7 postoperatively, improvement after 4 years by 53.7%; VAS for radicular pain, 6.3 pre-operatively, 2.9, 2.9 and 2.7 postoperatively, improvement by 57.1% after 4 years. The radiographic findings showed the average intervertebral disc space height of 3.2 mm at the affected level before and 7.4 mm after surgery, with no significant change in the following period. The average range of disc motion at the affected level was 4.2 degrees before and 11.1 degrees after surgery, with 11.4 degrees at 4 years of follow-up. During that period, heterotopic ossification was recorded in 10 (25%) treated discs, with five of them (12.5%) classified as grade III or IV. Spontaneous fusion across the disc replacement level was found in three cases (7.5%). Two patients (5%) developed kyphosis at the affected disc level. The statistical analysis showed a significant difference between the pre-operative VAS values and those at 6 post-operative weeks for both cervical spine and radicular pain (t = 4.4 and t = 5.3, respectively; p < 0.05). No significant difference in VAS values was found between 6 weeks and 3 months after surgery for either condition (t = 1.69 and t = 0.3; p > 0.05). Changes in VAS values in the following period were minimal and non-significant. The differences in NDI values before surgery and at 6 weeks after it, and between 6 weeks and 3 months post-operatively were significant (t = 11, p < 0.05 and t = 3.8, p < 0.05, respectively). In the following period, changes in the values were minimal and non-significant., Discussion: Short-term studies on various types of cervical disc replacement have been optimistic and reported good clinical results and few complications. However, with longer follow-ups there has been an increasing incidence of heterotopic ossification as the most frequent late complication. Although the number of patients diagnosed with it is growing, heterotopic ossification influences the patient's clinical problems only little. What are its causes and how to prevent it are questions to be fully answered yet, Conclusions: Heterotopic ossification is the most frequent late complication of total disc replacement. Many factors may be responsible for its development and therefore its prevention is not clear. The correct indication and appropriate surgical technique are most often recommended, and are considered also by the authors to be most important. Restricted motion at the treated segment/s has no significant effect on the patient's clinical status.

Chronic anthracycline cardiotoxicity is a feared complication of cancer chemotherapy. However, despite several decades of primarily hypothesis-driven research, the molecular basis of this phenomenon remains poorly understood. The aim of this study was to obtain integrative molecular insights into chronic anthracycline cardiotoxicity and the resulting heart failure. Cardiotoxicity was induced in rabbits (daunorubicin 3mg/kg, weekly, 10weeks) and changes in the left ventricular proteome were analyzed by 2D-DIGE. The protein spots with significant changes (p<0.01, >1.5-fold) were identified using MALDI-TOF/TOF. Key data were corroborated by immunohistochemistry, qRT-PCR and enzyme activity determination and compared with functional, morphological and biochemical data. The most important alterations were found in mitochondria - especially in proteins crucial for oxidative phosphorylation, energy channeling, antioxidant defense and mitochondrial stress. Furthermore, the intermediate filament desmin, which interacts with mitochondria, was determined to be distinctly up-regulated and disorganized in its expression pattern. Interestingly, the latter changes reflected the intensity of toxic damage in whole hearts as well as in individual cells. In addition, a marked drop in myosin light chain isoforms, activation of proteolytic machinery (including the proteasome system), increased abundance of chaperones and proteins involved in chaperone-mediated autophagy, membrane repair as well as apoptosis were found. In addition, dramatic changes in proteins of basement membrane and extracellular matrix were documented. In conclusion, for the first time, the complex proteomic signature of chronic anthracycline cardiotoxicity was revealed which enhances our understanding of the basis for this phenomenon and it may enhance efforts in targeting its reduction., (Copyright © 2011 Elsevier Ltd. All rights reserved.)