Levamisole-associated multifocal inflammatory encephalopathy: clinical and MRI characteristics, and diagnostic algorithm.

Levamisole-associated multifocal inflammatory encephalopathy (LAMIE) is a devastating adverse effect of levamisole (LEV) treatment. In Russia, people often use LEV without a doctor's prescription for anthelmintic prophylaxis. LAMIE often misdiagnosed as the first episode of MS or acute disseminated encephalomyelitis (ADEM). The aim of our study was to describe clinical, laboratory and morphological characteristics of LAMIE, magnetic resonance imaging (MRI) patterns and create an algorithm for the differential diagnosis. This study was a prospective observational study with retrospective analysis of cases. It was performed at two hospitals with ambulatory service for MS. We included 43 patients with LAMIE with follow-up was from 1 year to 5 years. Age was 19-68 y.o. with female predominance. The most typical manifestations of LAMIE were cerebellar, pyramidal and cognitive symptoms, and majority of patients had biphasic course of the disease. Three main types of MRI patterns were described: ADEM-like, MS-like, atypical demyelination. About 40% of patients had CSF specific oligoclonal bands synthesis, but only 20 % of them converted to MS during the period from 1 month until 2 years. The CSF albumin levels and immunoglobulin G index were elevated in LAMIE patients compared to reference values. We described results of brain biopsy in two cases. Therefore LAMIE should be considered in patients with demyelinating or inflammatory conditions with biphasic onset of the disease and variable MRI presentation.

[The effect of non-invasive brain stimulation on neuroplasticity in the early recovery period after ischemic stroke]. / Vliyanie neinvazivnoi stimulyatsii golovnogo mozga na neiroplastichnost' v rannem vosstanovitel'nom periode ishemicheskogo insul'ta.

The post-stroke cognitive impairment syndrome (PSCI) develops in 10-80% cases of ischemic stroke and leads to a significant patients' quality of life impairment. The standard program of cognitive rehabilitation includes nootropic agents therapy and neuro-cognitive training. The additional various methods of non-invasive brain stimulation (NIBS) application can improve the results of PSCI rehabilitation. PURPOSE OF THE STUDY: Studying the different variants of NIBS influence on synaptic neuroplasticity in the early recovery period after ischemic stroke. MATERIAL AND METHODS: The rehabilitation of 62 patients with PSCI syndrome after ischemic stroke outcomes were studied. The patients were assigned to 5 groups. Patients from the control group underwent standardized nootropic therapy and course sessions with a neuropsychologist. The rest of the patients were divided into 4 groups, in which, in addition to the basic program of cognitive rehabilitation, different options for the course use of NIBS were used: photochromotherapy (PCT) with narrow-band optical radiation (NOR) with a wavelength of 530 nm (green light); rhythmic transcranial magnetic stimulation (rTMS) with a low-intensity high-frequency running pulsed magnetic field; infrared radiation with a wavelength of 1-56 microns, modulated by terahertz frequencies (IRMT); bioacoustic correction (BAC). We analyzed the dynamics of changes in scores of MMSE scales, FAB, Roshchina. In order to assess the effect of NIBS on neuroplasticity, the concentrations of BDNF and antibodies to the NR2 fragment of the NMDA receptor were evaluated before and after the completion of the rehabilitation course. RESULTS: Concentration values of antibodies to the NR2 subunit of the NMDA receptor in all groups remained consistently above the norm (more than 2 ng/ml) throughout the entire course of rehabilitation. Differences between groups in the dynamics of BDNF concentration in the peripheral blood were revealed. There was a significant (p<0.05) decrease in its concentration by almost 2 times by the end of rehabilitation course in control group. In the rTMS and IRMT groups, a decrease in the BDNF concentration was also recorded in dynamics, which, however, did not reach a significant level. There was no decrease in BDNF levels in the BAC group. There was an increase of this level in the PCT group. CONCLUSION: The use of different types of NIBS in the program of cognitive rehabilitation of patients with PSCI syndrome contributes to an increase in the rehabilitation potential due to the activation of neurotrophin-mediated synaptic neuroplasticity. Green light PCT and BAC have the greatest effect on increasing neuroplasticity after ischemic stroke.

[Structural epilepsy or herpes simplex encephalitis relapse: diagnostic problems]. / Strukturnaya epilepsiya ili retsidiv gerpeticheskogo entsefalita: diagnosticheskie trudnosti.

The article gives the clinical case of herpes simplex encephalitis relapse with the resistant seizures in a child. What we describe is a clinical approach towards the differential diagnostic of the seizures in structural epilepsy, which are resistant to anticonvulsants, or late herpes simplex encephalitis relapse. Good clinical perspective may be the indication of the intratecal synthesis of the IgG-specific antibodies to the herpes simplex type 1 and 2. Conducting etiotropic treatment with the appointment of acyclovir and pathogenetic therapy with the use of Cytoflavin contributed to the rapid and stable remission of epileptic seizures and regression of neurological deficit.

[Acute disseminated encephalomyelitis]. / Ostryi rasseyannyi entsefalomielit.

Acute disseminated encephalomyelitis (AEM) is an immune-mediated inflammatory demyelinating disease of the central nervous system (CNS), usually single-phase. In WREM, multiple lesions of the central nervous system of an inflammatory-demyelinating nature accompanied by extremely polymorphic neurological disorders develop acutely or subacutely. The review considers the issues of epidemiology, trigger factors of the inflammatory process, clinical manifestations, differential and molecular diagnostics of WECM, and outlines the ways for further study of this pathology.

Acrodystrophic axonal polyneuropathy with celiac disease: a case report.

BACKGROUND: Patients with celiac disease present with not only gastrointestinal symptoms but also extraintestinal manifestations such as anemia, osteopathy, dermatitis herpetiformis, and celiac neuropathy. Despite a fairly wide range of celiac neuropathies, we report a case of the acrodystrophic variant of celiac polyneuropathy, which has not been previously described. CASE PRESENTATION: A 41-year-old Ukrainian male suffered from symmetric, sensorimotor axonal polyneuropathy and encephalopathy associated with celiac disease, which is characterized by severe trophic disorders in the lower extremities (trophic ulcers, hyperkeratosis, and anhidrosis). Acrodystrophic changes in the lower extremities were due to both neurogenic and direct immunoinflammatory damaging effects. Clinical-electrophysiological dissociation was also noted, which was represented by a gross axonal lesion with the preservation of muscle strength. The absence of enteropathic manifestations was accompanied by the pronounced histological changes in the duodenal mucosa by IIIb stage of Marsh. A gluten-free diet in combination with membrane plasma exchange and intravenous pulse methylprednisolone was prescribed to reduce the severity of sensory disorders and regression of encephalopathy within 7 months. CONCLUSION: Celiac disease may be a potential cause of neuropathy and encephalopathy in adult patients. Further immunosuppressive treatment protocols for both intestinal and extraintestinal manifestations of celiac disease are required.

Cytotoxic activity of 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide is underlain by DNA interchain cross-linking.

Currently, chemical bifunctional cross-linkers are regarded as promising therapeutic agents capable of affecting cell metabolism. Depending on the nature of the active groups and on the length of their mediating spacer, these cross-linkers have been shown to influence mitochondrial functions, the cell cycle and cell death. The current study was aimed to assay cellular effects of a cross-linker with 'zero'-length spacer, 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC). When added to cultures of transformed cells, EDC induced a G2/M blockade followed by cell death. Analysis of the molecular targets revealed that alteration of the cell cycle was caused by EDC-induced interchain cross-linking within double-stranded DNA. Administration of EDC to animals with experimental tumors increased their life span. The analysis of tumor cells from EDC-treated mice showed up-regulation of p21/WAF1, disturbance of tumor cell cytokinesis and, hence, cell death. Thus, both in vitro and in vivo, EDC exhibits cytotoxic activity, which may be of potential therapeutic use.

Cytotoxic signal transduction pathways via TNF family receptors.

Studies indicating an important role of the TNF-receptor family in control of cell proliferation, differentiation, and death have drastically increased in number in recent years. The main function of many members of this family is cell death triggering, and this is apparently the only function for some of them. Studies on the molecular mechanisms of cell death activated by members of the TNF-receptor family revealed and identified proteins directly or indirectly associated with TNF receptors. Pathways of cytotoxic signal transduction by some members of the TNF-Rs family based on currently proven protein-protein interactions and the role of distinct proteins in these processes are summarized in this review.

[Dimethyl suberimidate as a specific inductor of apoptosis in transformed cells]. / Dimetilsuberimidat kak spetsificheskii induktor apoptoza transformirovannykh kletochnykh kul'tur.

A modification of protein-protein interactions can be considered to be a way to regulate cell death. Chemical cross-linking agents have been traditionally used for protein complexing. This study has been undertaken to test a possibility to induce and(or) to modify cell death by a homobifunctional cross-linker dimethyl suberimidate (DMS). It was shown that the protein cross-linking by DMS resulted in a death of transformed cells by apoptosis. DMS-induced apoptosis was accompanied by cell cycle perturbations and down-regulation of p21/Waf1 mRNA expression. The RT-PCR analysis of bcl-2 family genes revealed the engagement of mitochondria in DMS-induced cytotoxicity. Then, the influence of DMS treatment on TNF-dependent and Fas-mediated apoptosis was investigated. Cell pre-incubation with DMS resulted in their increasing sensitivity for the TNF cytotoxic effect, though activities of anti-Fas cytotoxic antibodies were inhibited. The effects observed are probably due to cross-linking of TNF-receptors. Thus, this study first demonstrated that a chemical cross-linker DMS in capable of inducing apoptosis in transformed cells and modifying TNF-dependent and Fas-mediated apoptosis.

Cell death induced by chemical homobifunctional cross-linkers. Cross-linker induced apoptosis.

Physical association of proteins that underlies cytotoxic signal induction and transduction suggests a possibility of regulating cell response by modifying protein-protein interactions. For protein complexing, chemical cross-linking agents have been traditionally used. However, the ability of various cross-linkers to induce and modify cell responses, cell death in particular, is still obscure. We have undertaken the investigation to test the apoptosis-inducing and modifying properties of the homobifunctional cross-linkers-dimethyl suberimidate (DMS) and 1,5-bis(succinimido-oxycarbonyloxy)pentane (BSOCOP). The functional groups of these cross-linkers are different but both are able to interact with available amino groups. It was shown that bifunctional cross-linkers, unlike their monofunctional analogues, are capable of inducing cell death in transformed cells, thus indicating the crucial role of cross-linking in cell killing. DMS- and BSOCOP-treated cells were shown to undergo cell death by apoptosis, though the signaling pathways were distinct. DMS inhibited bcl-X(L) and bak but not bax gene expression, while BSOCOP potentiated bax mRNA synthesis immediately after application. Cell pre-incubation with DMS, but not with BSOCOP, resulted in an increasing sensitivity to TNF, although activities of anti-Fas cytotoxic antibodies were then inhibited. Thus, this study has demonstrated for the first time that chemical cross-linkers are capable of inducing apoptosis by themselves and modifying the TNF-dependent and Fas-mediated cell death that may have potential therapeutic significance.

[Apoptosis of L929 cells induced by tumor necrosis factor]. / Apoptoz kletok L929 pod deistviem faktora nekroza opukholei.

We investigated the mode of TNF-dependent death of L929 murine fibroblasts and the influence of overexpression of bcl-2 family genes on this process. Based on morphological and biochemical data it has been shown that L929 cells died after TNF treatment by apoptosis irrespective of TNF dose and protein synthesis inhibition. Analysis of bcl-2 family gene transfectants revealed a down-regulation of TNF-induced apoptosis by bcl-2 and bclX overexpression, and an up-regulation by bax gene.

Age- and radiation-dependent changes in carbonyl content, susceptibility to proteolysis, and antigenicity of soluble rat liver proteins.

Soluble liver proteins (SLP) from old and gamma-irradiated young rats were studied with respect to their carbonyl content, the rates of autolysis and degradation by proteinase K, and their antigenicity for mice and compared with SLP from non-irradiated young animals. A significant increase in the carbonyl level was found in SLP from old and gamma-irradiated young rats as compared to SLP from intact young rats. The rates of SLP autolysis and proteolysis by proteinase K were increased in the same animal groups but did not correlate the carbonyl level. At the same time, whereas the antigenicity for mice of SLP from old rats was significantly higher than that of SLP from young rats, the antigenicity of SLP from gamma-irradiated rats did not differ from non-irradiated animals. Enrichment of the diet with antioxidant and vitamin supplements (AVS) during one month before the irradiation caused a decrease in the radiation-induced carbonyl level in rat SLP. However, this raised antioxidant level in animal diet did not influence the rates of SLP autolysis and degradation by proteinase K and also did not alter the antigenicity of these proteins. The data allow us to suggest that the increase in autolysis, degradation by the exogenous proteinase, and antigenicity of SLP from old rats are determined not only by carbonyl formation in these proteins due to action of oxygen radicals but also by other age-specific protein modifications.

Monoclonal antibodies directed against unique and common determinants on the lipopolysaccharide molecule of Salmonella serogroups A, B, and D.

A panel of monoclonal antibodies (MAbs) directed against lipopolysaccharide (LPS) of Salmonella serogroups A, B, and D was generated. Nine most productive hybrid clones were selected from several fusions of mouse myeloma cells with splenocytes from BALB/c mice, immunized with the corresponding heat-killed bacteria. The MAbs were characterized by enzyme immunoassay, Western blot analysis, and dot-immunoblotting with LPS and whole bacteria of Salmonella serogroups A-E and some other representatives of the Enterobacteriaceae family. Seven MAbs were reactive with the sole Salmonella strain used as an immunogen; one MAb, SD:10D9H, reacted with the five major serogroups of Salmonella species (A, B, D, E1, and E2); and one MAb, SA:5D12A, reacted with Salmonella serogroups A-E and a rough strain of S. cholerae-suis. None of the MAbs reacted with LPS of E. coli 055:B5 or whole bacteria of E. coli K12, Klebsiella pneumoniae, or Proteus vulgaris. The typical ladder-like patterns of bands were observed after immunoblotting of MAbs against electrophoretically resolved LPS from Salmonella serogroups A-E, which thus confirmed their LPS-directed specificity. MAbs affinity constants were determined by noncompetitive enzyme immunoassay using serial dilutions of both LPS as antigen (coating the plate) and antibodies. On the base of the results obtained, the presumed epitopes for each of the MAbs were discussed. The usefulness of MAbs generated for diagnostic and protective purposes was declared.

[Solid-phase synthesis of peptides modelling the transmembrane segment of bacteriorhodopsin]. / Tverdofaznyi sintez peptidov, modeliruiushchikh transmembrannye segmenty bakteriorodopsina.

Peptides modelling transmembrane segments C, D, E and G of bacteriorhodopsin were obtained by solid phase method using the conventional Boc strategy. Protected peptides were assembled on PAM polystyrene support. Side chain protecting groups were: Tos for Arg, Bzl for Thr and Ser, cHx for Asp and Glu, Bzl(Cl2) for Tyr, For for Trp, Z(Cl) for Lys. Syntheses were performed on a modernized Beckman 990 synthesizer in the automatic mode. Double couplings by a preformed hydroxybenzotriazole ester were used for all residues. Qualitative and quantitative ninhydrine tests were used to monitor coupling efficiency. Removal of protecting groups and peptide cleavage were achieved by hydrogen fluoride, containing p-cresol and p-thiocresol as scavengers. Preparative reverse phase HPLC was used for purification. Peptide structure and homogeneity were confirmed by amino acid analysis, 1H-NMR and analytical HPLC.

The fusion of artificial lipid membranes induced by the synthetic arenavirus 'fusion peptide'.

The fusing activity of the synthetic 23 amino-acid fragment (fusion peptide, FP) of the fusion protein of the Lassa arenavirus membrane was tested in a model liposomal system. The resonance energy transfer between two fluorescent phospholipid probes was monitored in order to detect dioleoylphosphatidylcholine liposome fusion induced by the peptide. Fusion rates were compared at different pH values, ionic strength and calcium concentrations. FP demonstrated fusing activity at pH 4.5-5.5, indicating that the protonated form of the FP is the active one. A transmembrane proton-gradient induced by acidification was not relevant to the fusion process, since its elimination with nigericin did not affect the FP-mediated fusion. Both Ca2+ (8 mM) and the increase of the ionic strength (1 M NaCl) inhibited liposome fusion. The efficacy of liposome fusion depended also on the lipid-to-lipid ratio. Non-linear dependence was observed at a saturation ratio of 10 mol lipid per mol peptide. A model of 'side insertion' is suggested, describing FP interaction with the membrane.

[Fusion of artificial lipid membranes induced by synthetic "fusion peptide" of arenaviruses]. / Sliianie iskusstvennykh lipidnykh membran indutsiruemoe sinteticheskim "peptidom sliianiia" arenavirusov.

The fusing capacity of lipid membranes of a synthetic 23-member peptide was studied. This hydrophobic peptide represents an analog of a predicted functional site ("fusion peptide") of the GP2 envelope protein of the Lassa virus (family Arenaviridae). Fusion of small monolayer liposomes was detected by the method of resonance energy transfer between the fluorescent derivatives of the lipid, NBD-PE (donor) and Rd-PE (acceptor). Using this peptide, the pH-dependent fusing activity was found in liposomes having different phospholipid composition. The rate and efficiency of liposome fusion increased with a decrease in pH and the lipid/peptide ratio as well as with a temperature increase. The increase in the ionic strength and Ca2+ concentration in the reaction mixture led to the inhibition of the peptide-induced fusion of liposomes. Neither the phospholipid charge, nor the transmembrane proton gradient of liposomes had any appreciable effect on the kinetics of the peptide-induced fusion. Neutralization of the medium in the course of the fusion reaction sharply decelerated, whereas repeated acidification activated this process. This finding suggests that peptide protonation plays a role in fusion reactions. It was suggested that acidification causes conformational changes in the peptide structure, thus activating the peptide-induced fusion of liposomes. The fusing capacity of the predicted Lassa virus fusion peptide is similar to that of viruses characterized by a pH-dependent step at the initial stages of the viral infection.

[Identification of a protective epitope--a fragment of Lassa virus nucleoprotein]. / Identifikatsiia protektivnogo épitope--fragmenta nukleoproteina virusa Lassa.

Several peptides from Lassa virus glyco- and nucleoproteins were predicted as probable T-cell epitopes. Their synthesis was performed by solid phase method. The study of possible protective effect in vivo with Lassa-sensitive CBA mice revealed protective epitope within the 277-303 nucleoprotein region. Further studies reduced the protective epitope structure to the 287-300 nucleoprotein fragment.

Lassa virus glycoproteins: antigenic and immunogenic properties of synthetic peptides to GP1.

Synthetic peptides corresponding to predicted Lassa virus GP1 glycoprotein B-epitopes were used to study the antigenicity and immunogenicity of the protein. ELISA results showed that guinea pig polyclonal anti-Lassa virus serum bound effectively to peptides corresponding to amino acid residues 119-133 and 164-176 of the GP1 protein. Essentially it did not react to a peptide corresponding to GP1 amino acid residues 234-256. Sera obtained against peptides representing amino acid residues 119-133 and 164-176 reacted with inactivated purified Lassa virus.