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Introduction and objective: Two-thirds of patients with hepatitis C virus (HCV) infection are unaware of their infection in the European Union. The WHO aims to reduce the number of new cases of chronic hepatitis by 90% by 2030. The proportion of people infected with HCV in prisons can be up to ten times higher compared to the general population. This article is a summary of the results of the HCV screening carried out in the Hungarian prisons between 2007 and 2017. Method: Screening of anti-HCV antibodies has been performed on a voluntary basis followed by HCV PCR and genotyping in positive cases. After obtaining written informed consent from the patients, treatment was started. Treatments were performed under the guidance of hepatologists in collaboration with prison medical staff. Results: HCV screening programs and treatments are in place in 84% of Hungarian prisons. A total of 25 384 patients underwent anti-HCV screening. Anti-HCV positive result was detected in 6.6% and HCV PCR positivity was confirmed in 3.8% of the screened inmates. 55.2% patients from the HCV PCR positive population were put on treatment. Only 143 patients received full treatment, while 162 (42.6%) treatments were terminated prematurely, and the duration of treatment was unknown in 75 patients. Based on the results available on the 24th week after the end of treatment, sustained virologic response rate was 88%. Discussion: Education of patients and collaboration between hepatologists and prison medical staff play an important role in the successful result of treatment. Conclusion: Our experience demonstrates that the test and treat principle is feasible and effective at microeliminating HCV in prisons.

The aim of the present paper was to check for the presence of cerebrovascular dystroglycan in vertebrates, because dystroglycan, which is localized in the vascular astroglial end-feet, has a pivotal function in glio-vascular connections. In mammalian brains, the immunoreactivity of β-dystroglycan subunit delineates the vessels. The results of the present study demonstrate similar patterns in other vertebrates, except for anurans and the teleost groups Ostariophysi and Euteleostei. In this study, we investigated 1 or 2 representative species of the main groups of Chondrichthyes, teleost and non-teleost ray-finned fishes, urodeles, anurans, and reptiles. We also investigated 5 mammalian and 3 bird species. Animals were obtained from breeders or fishermen. The presence of β-dystroglycan was investigated immunohistochemically in free-floating sections. Pre-embedding electron microscopical immunohistochemistry on Heterodontus japonicus shark brains demonstrated that in Elasmobranchii, β-dystroglycan is also localized in the perivascular glial end-feet despite the different construction of their blood-brain barrier. The results indicated that the cerebrovascular β-dystroglycan immunoreactivity disappeared separately in anurans, and in teleosts, in the latter group before its division to Ostariophysi and Euteleostei. Immunohistochemistry in muscles and western blots from brain homogenates, however, detected the presence of β-dystroglycan, even in anurans and all teleosts. A possible explanation is that in the glial end-feet, β-dystroglycan is masked in these animals, or disappeared during adaptation to the freshwater habitat., (© 2019 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.)

Aim of the Study: Combination of ombitasvir/paritaprevir/ritonavir + dasabuvir ± ribavirin (3DDA±RBV) therapy is shown to be effective in HCV genotype 1 (GT1) infected patients. However, sparse data exist in patients who failed previous boceprevir or telaprevir based therapies. Real life efficacy and safety of this combination were evaluated in HCV GT1b infected patients (mostly cirrhotics) with compensated liver disease who failed previous boceprevir or telaprevir based therapies more than a year before., Material and Methods: Data of previous protease inhibitor failure patients, treated with 3DAA+RBV for 12 weeks (GT1b and/or non-cirrhotics) or 24 weeks (non-GT1b cirrhotics), were retrospectively collected., Results: Population characteristics: boceprevir/telaprevir-failure: 82/45, GT1b: 117, cirrhotic: 111 (87.4%). SVR12/24 was observed in 103/105 patients (98.1%) of those who reached either time point. Four SAEs reported: one death due to myocardial infarction, another due to recurrent hepatocellular carcinoma after achieving SVR12, two hospitalizations (elevation of transaminases, pneumonia). Grade ≥ 3 AEs or laboratory abnormalities were reported in < 10% of patients; they were transient in all patients. No early discontinuation of drugs due to SAE has been reported., Conclusions: One year after previous failure of boceprevir or telaprevir based therapy, 12 weeks of 3DAA+RBV combination in HCV GT1b infected patients is similarly effective and safe as in those with no previous HCV therapy, even in the presence of cirrhosis. These findings might be of particular interest in settings where alternative therapies for such patients are not available or not affordable., Competing Interests: Authors report no conflict of interest.

Melanin-concentrating hormone (MCH) is a potent orexigenic and sleep-promoting neuropeptide in mammals produced predominately by hypothalamic neurons which project to a wide variety of brain areas. Several MCH producing neurons contain MCH as the only neuropeptide, while others comprise cocaine- and amphetamine regulated transcript (CART) as well. The intrahypothalamic localization and the projection pattern of these two subpopulations are distinct. To provide structural grounding to understand the mechanism of action of MCH neurons we show here the subcellular localization of the neuropeptides in the two subpopulations within the hypothalamus of healthy young male mice by applying single and double immunofluorescence labelling.; Thick, prominent MCH immunopositive reticulation and fine discrete granules are detected within the perikarya of both CART positive and CART-free MCH neurons. Typically, one or more immunoreactive processes emanate from the perikarya. The bulk of CART immunoreactivity is also centrally positioned, surrounded by sparse immunoreactive granules within the perikarya and in the processes. In double immunopositive neurons, the two neuropeptides seem to colocalize in the heavily labelled central area, while the immunopositive granules in the cell body periphery and in the processes apparently contain either MCH or CART. This spatial arrangement suggests that MCH and CART, after being synthetized and processed in the endoplasmic reticulum/Golgi complex, are sorted into separate dense core vesicles, which then enter into the cell processes. This mechanism allows for both concerted and independent regulation of the transport and release of MCH and CART., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Melanin-concentrating hormone (MCH), the neuropeptide produced mainly in the hypothalamus, plays an operative role in regulating food intake and the sleep/wake cycle. Considering that these physiological functions pursue diurnal variations, we checked whether the total hypothalamic MCH level depends on the time of the day. The aggregated MCH peptide content of the whole MCH neuron population was significantly higher at the end of the sleeping period (lights on), than at the end of the active period (lights off). This result, together with earlier observations, indicates that in contrast to the MCH gene expression, the level of MCH peptide is object of circadian variation in the hypothalamus.

Introduction: During 2011 and 2013, 155 Hungarian hepatitis C genotype 1 infected patients, mostly with advanced liver fibrosis, who did not respond to prior peginterferon + ribavirin dual therapy, started boceprevir based triple therapy in an early access program., Aim and Method: Efficacy and safety of the therapy was retrospectively assessed based on sustained virologic responses, as well as on frequency and type of serious adverse events and of those leading to therapy discontinuation., Results: In an intent-to-treat analysis 39.4% patients (61/155) reached sustained virologic response. Amongst pervious relapsers, partial responders and null-responders 59.5%, 41.4 % and 22.9% (p<0.05 compared to the other two categories) reached sustained virologic response, respectively, while amongst non-cirrhotics and cirrhotics 52.5% and 31.3% (p<0.05 compared to the non-cirrhotics) achieved sutained virologic response, respectively. Six out of the 33 most difficult to cure patients (previous null responder and cirrhotic) have reached sustained virologic response (18.2%). Frequency of early discontinuations due to insufficient virologic response was 31.1%, while due to adverse event 10.3%. Reported frequency of serious adverse event was 9.8%. These events represented anemia, diarrhoea, depression, agranulocytosis, elevated aminotransferases, generalized dermatitis and severe gingivitis with loss of teeth, prolonged QT interval on ECG, generalized oedema and severe dyspnoea, uroinfection, exacerbation of Crohn's disease, Campylobacter pylori infection and unacceptable weakness and fatigue. Eight patients received transfusion, 4 patients erythropoietin and 1 granulocyte colony stimulating factor during therapy. No death has been reported., Conclusions: With boceprevir based triple therapy, one of the bests available in 2011-2013 in Hungary, a relevant proportion of hepatitis C infected patients with advanced liver fibrosis achieved sustained viral response. In this cohort, side-effects resembled those reported in registration studies, and resulted in therapy discontinuation with consequent treatment failure in a relevant number of patients. Efficacy and tolerability of boceprevir-based triple therapy are suboptimal, particularly in the most difficult to cure patient population. Orv. Hetil., 2016, 157(34), 1366-1374.

We present here a new procedure to represent the 3D distribution of neuronal cell bodies within the brain, using exclusively softwares free for research purposes. Our technique is based on digitalized photos of brain slices processed by immunohistochemical technique, and the 3D Slicer software. The technique presented enables transposition of immunohistochemical or in situ hybridization data to the stereotaxic mouse brain atlas (e.g. Paxinos, G., Franklin, K.B.J., 2001. The Mouse Brain in Stereotaxic Coordinates. second ed. Academic Press, San Diego). By exporting the finalized models into a popular 3D design software (3DS Max) arbitrary environment and motion simulation can be created to improve the visual understanding of the area studied. Application of this technique provides the possibility to store, analyze and compare data - e.g. on the hypothalamic neuropeptides - across experimental techniques and laboratories. The method is exemplified by visualizing the distribution of immunohistochemically identified melanin-concetrating hormone (MCH) containing perikarya within the mouse hypothalamus., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The vascular disease involves imbalanced function of the blood vessels. Risk factors playing a role in development of impaired vessel functions will be briefly discussed. In ischemia/reperfusion (I/R), ischemic hypoxia is one of the cardinal risk factors of restenosis. Various insults are shown to initiate the phenotype switch of VSMCs. The pathological process, leading to activated inflammatory process, complement activation, and release of growth factors, initiate the proliferation of VSMCs in the media and cause luminal narrowing and impaired vascular function. The review summarizes the alteration process and demonstrates some of the clinical genetic background showing the role of complement and the genotypes of mannose-binding lectin (MBL2). Those could be useful markers of carotid restenosis after stent implantation. Gene therapy and therapeutic angiogenesis is proposed for therapy in restenosis. We suggest a drug candidate (iroxanadine), which ensures a noninvasive treatment by reverse regulation of the highly proliferating VSMCs and the disturbed function of ECs.

The expression of the two members of the dystrobrevin (DB) family in the adult brain was thought to be highly specific for the two main cell types: alpha-dystrobrevin (alpha-DB) and beta-dystrobrevin (beta-DB) has been identified as glial and neuronal proteins, respectively. In the present work we show that a subset of neurons in the hypothalamus contains alpha-DB. Comparative immunohistochemical studies with two alpha-DB antibodies of different specificity indicate that the neurons contain short alpha-DB isoform(s) alpha-DB-2 and/or alpha-DB-4. Immunoreactive multipolar or spindle-shaped neurons form clusters with bilateral symmetry, localized predominantly in the lateral hypothalamic area, with extensions into the zona incerta and the dorso-medial and ventro-medial hypothalamic region. alpha-DB immunoreactivity was localized in cell processes and at postsynaptic densities, furthermore in the endoplasmic reticulum within the perikarya. alpha-DB-positive neurons are beta-dystrobrevin immunoreactive, but alpha- and beta-DB do not co-localize with their usual molecular anchors like dystrophins or high molecular weight forms of utrophin. Colocalization with nNOS was also not observed. The pattern of alpha-DB immunoreactive neurons gave a perfect colocalization with melanin-concentrating hormone (MCH) neurons throughout the whole region studied. We propose that alpha-DB plays a role in a structure or regulation mechanism unique to MCH-expressing neurons.

The alpha- and beta-dystrobrevins (DBs) belong to a family of dystrophin-related and dystrophin-associated proteins that are members of the dystrophin-associated protein complex (DAPC). This complex provides a link between the cytoskeleton and the extracellular matrix or other cells. However, specific functions of the two dystrobrevins remain largely unknown, with alpha-DB being believed to have a role mainly in skeletal muscle. Here, we describe previously unknown expression patterns and the localisation and molecular characteristics of alpha-DB isoforms in non-muscle mouse tissues. We demonstrate a highly specific sub-cellular distribution of alpha-DB in organs forming blood-tissue barriers. We show alpha-DB expression and localisation in testicular Sertoli cells, stomach and respiratory epithelia and provide electron-microscopic evidence for its immunolocalisation in these cells and in the central nervous system. Moreover, we present the molecular characterisation of alpha-DB transcript in these tissues and provide evidence for a distinct heterogeneity of associations between alpha-DB and dystrophins and utrophin in normal and dystrophic non-muscle tissues. Together, our results indicate that alpha-DB, in addition to its role in skeletal muscle, may also be required for the proper function of specific non-muscle tissues and that disruption of DAPC might lead to tissue-blood barrier abnormalities.

It has previously been demonstrated that Dp71, the most abundant dystrophin protein in the brain, is mainly localized in the postsynaptic densities. Here we show the localization of Dp71f, one of the splice variants of this protein, within the CA3 region of the hippocampus. Immunopositivity occurs in the postsynaptic density of small asymmetrical axospinous and axodendritic synapses, while it is absent in the postsynaptic densities of the axospinous synapses of the large mossy fiber terminals. Dp71f immunoreactivity was found to be attached to the membranes of the mossy fibers in the stratum lucidum of the CA3 area. In a certain population of thin myelinated axons the protein seems to be present within the axon proper. These data support the notion of a physiological role of Dp71f distinct from other dystrophin isoforms present in the central nervous system.

We investigate the role of dystroglycan, a major laminin-1 receptor and central member of the dystrophin-glycoprotein complex, in the laminin-1 induced motility of cultured Muller glial cells. Binding of laminin-1 to dystroglycan was prevented by IIH6, a function-blocking monoclonal antibody against alpha-dystroglycan. As an alternative means of inhibition, we used heparin to mask the dystroglycan binding site of the laminin-1, known to overlap with heparin binding sites. Cell motility was characterized in a two-dimensional motility assay based on computer-controlled videomicroscopy and statistical analysis of cellular trajectories. We obtained data on both the cell velocity and the diffusion index, a measure of direction-changing frequency. Both means of inhibition of dystroglycan function led to a significant decrease in the ability of laminin-1 to stimulate cell migration. At the same time, dystroglycan function does not appear to be involved in laminin-1-dependent increase in process dynamism and direction-changing activity.

Dystrophins are membrane-associated actin-binding proteins, recognized at first in muscular dystrophies. In the brain the full-length Dp427 has been detected, as well as Dp140 and Dp71 of the shorter variants. Dp71 seems to be their major representative in the brain, and it occurs as splice variants, Dp71f and Dp71d. Dystrophins have been demonstrated mainly in neurons. In tissue cultures, the glial data, mainly in situ, are still insufficient. The present mapping study reveals the astroglial localization of the splice variant Dp71f, using a monoclonal antibody (5F3, developed by D. Mornet) specific for its additional 31 last amino acids. In parallel, another monoclonal antibody was used (Dys2, Novocastra) that detects the Dp71d, Dp427, as well as Dp140 and other short variants. Rats were overdosed with ether and perfused transcardially with 4% phosphate-buffered paraformaldehyde solution. Floating Vibratome sections were processed for immunohistochemical labeling with fluorescent secondary antibodies. In some animals the reactive glia were investigated following stab wounds in ketamine-xylazine anesthesia. Only the 5F3 antibody labeled astrocytes, however, not in general but in special localizations, mainly along the glia limitans of the pial surface, below the ependyma and in the reactive glia. Perivascular astrocytes were consistently labeled only where the vessels entered the brain, and in some circumventricular organs. The 5F3 antibody also labeled the ependyma and the residual subventricular zone. In contrast to the astrocytes, neurons were labeled throughout the brain. Dys2 antibody (to Dp71d and longer isoforms) labeled neurons in a distribution similar to that of 5F3, but rarely labeled astroglia and only in perivascular rings. Dp71f positivity seems to occur in those astrocyte populations that proved to be immunopositive to glial fibrillary acidic protein (GFAP) and produced laminin in former studies.

The dystrophin glycoprotein complex (DGC) is a membrane-associated protein complex binding extracellular matrix (ECM) molecules, such as laminin and forming a bridge towards the cytoskeleton. The molecular composition of the DGC is cell type dependent and it is involved in cell adhesion and motility. Here we present immunocytochemical localization of beta-dystroglycan, the central member of the DGC, utrophin and Dp71f, the spliced 71 kDa dystrophin protein product of the DMD gene, in cultured retinal Muller glial cells. It is shown that beta-dystroglycan and utrophin are colocalized in clusters in all parts of Muller cells including the lamellipodium and leading edge of migrating cells. As a contrast, Dp71f labels are distinct from beta-dystroglycan and confined to the perinuclear cytoplasm of Muller cells indicating that Dp71f is not a member of the DGC in cultured Muller cells.

Spatial correlation was observed between the localization of laminin-1 at the inner limiting membrane (ILM) and extensive Muller glial process arborization in the same area, as demonstrated by immunolabeling of Muller glial processes and laminin-1 in rat retinae in situ. To test if this spatial correlation is due to a functional relationship, we investigated the impact of laminin-1 on the motility of cultured primary rat and mouse retinal Muller glial cells by statistical analysis of computer-controlled videomicroscopic time-lapse images. We demonstrate that laminin-1 increases motility and path-searching activity of Muller cells in vitro and it also enhances the cells' process formation/withdrawal dynamism. The increase in path-searching activity and cell process dynamism indicates that there is a functional relationship between laminin-1 and Muller glial cells presumably involving signaling towards the cytoskeleton. We hypothesize that laminin-1 is involved in process arborization of Muller cells at the vitread border of the retina resulting in the formation of the functional barrier made up of Muller glial endfeet., (Copyright 2002 Wiley-Liss, Inc.)

Maternal immunity is mediated exclusively by colostral immunoglobulins in ruminants. As the neonatal Fc receptor (FcRn) is suggested to be involved in the transport of immunoglobulin G (IgG) in the mammary gland, we cloned this receptor from sheep and analysed its expression in the mammary gland around the time of parturition and also in the small intestine from the newborn lamb. FcRn heavy-chain mRNA was detected (by using in situ hybridization) exclusively in the acinar and ductal epithelial cells in mammary gland biopsies both before and after parturition. Immunohistochemistry revealed that the cytoplasm of the epithelial cells of the acini and ducts in the mammary gland biopsies stained homogeneously before parturition. A remarkable difference was observed in the pattern after lambing, where the apical side of the cells was strongly stained. The presence of the FcRn in the acinar and ductal epithelial cells of the mammary gland, and the obvious change in distribution before and after parturition, indicate that the FcRn plays an important role in the transport of IgG during colostrum formation in ruminants. Immunohistochemical analysis detected a strong apical and a weak basal FcRn signal in the duodenal crypt cells of a neonatal lamb, which have been previously demonstrated to secrete IgG1 in newborn ruminants. The FcRn was not detected in the duodenal enterocytes, which absorb intact IgG from the colostrum in a non-specific manner. These data suggest that FcRn is involved in IgG1 secretion in ruminant epithelial cells.

Among the multiple functions, which have been identified for the neonatal Fc receptor (FcRn), we study its role in the IgG transport in the mammary gland during the colostrum formation. For this reason, we have obtained several mammary gland biopsies from a pregnant sheep around parturition. The presence of the FcRn heavy chain mRNA was detected exclusively in the acinar and ductal epithelial cell by in situ hybridization (ISH). We detected strong signal in samples harvested 24 and 10 days prepartum; however, in samples we collected postpartum was barely detectable. Immunohistochemistry confirmed our ISH data. The cytoplasm of the epithelial cells of the acini and ducts in the mammary gland biopsies stained homogeneously before parturition, although a remarkable difference was observed in the pattern after lambing. The signal indicated uneven distribution of the FcRn alpha chain in the epithelial cells 1 and 5 days postpartum, since the apical sides of the epithelial cells were highlighted. The presence of the FcRn in the acinar and ductal epithelial cells and the obvious change of its distribution before and after parturition suggest that FcRn plays an important role in the IgG transport during colostrum formation. FcRn expression was also found in the lamb duodenal crypt epithelial cells, which have been previously demonstrated to secrete IgG1 in newborn ruminants, suggesting secretory role of the FcRn in ruminant epithelial cells.

Piglets born with spread-leg syndrome, a congenital weakness of the hindlimb adductors, were investigated to determine the site of lesion leading to limb impairment. Histological and immunohistochemical studies of the motor neuron unit showed no alterations but quantitative analysis revealed a reduction of axonal diameter and myelin sheath-thickness of the fibres innervating the adductors of the affected limbs. In the lumbar spinal cord a lack of myelination was observed in the tracts descending to the lower motor neurons. Recovery from the syndrome was accompanied by a catching-up of myelination with that of the controls. The spread-leg syndrome is due to a nutritional deficiency in the sow; thus it is assumed that the deficient maternal substances, mainly choline and methionine, are essential for the normal myelin production by spinal white matter oligodendrocytes of the fetus.

Dystrophin, utrophin and dystroglycan are present not only in muscle but also in brain. In muscle, they link the extracellular matrix to the cytoskeleton. Their function in brain is not understood. Here we show their presence in the hypothalamo-neurohypophysial system which secretes the neurohormones oxytocin and vasopressin. Using immunocytochemistry, we showed that dystrophins are present in the neurohypophysis of control rats. After water deprivation, immunoreactivity dramatically decreased and appeared in axonal swellings in the hypothalamic tract. Dystrophin immunostaining can be ascribed to dystrophin and/or utrophin as well as the DMD (Duchenne Muscular Dystrophy) gene short products Dp140 and Dp71 as revealed by Western immunoblots of synaptosomes isolated from neurohypophyses of control rats. In synaptosomes isolated from rats under water deprivation, the immunoreactivity entirely disappeared. Further biochemichal characterization of isolated neurosecretory granules (NSG) showed that Dp140 and Dp71 are enriched in the NSG stored in the swellings of the neurohypophysis whereas the NSG of the nerve endings are devoid of these proteins. In addition we observed that the presence of beta-dystroglycan and actin correlates with the presence of dystrophins. Our data favor a direct implication of the dystrophins and/or utrophin, dystroglycan and actin in the neurosecretory processes of the hypothalamo-neurohypophysial system.

Dystrophin immunocytochemistry was carried out using monoclonal antibody against the C-terminal part of dystrophin (Dys2) in rat cerebral cortex, cerebellum and hippocampus containing a high number of spine synapses of similar morphological character. Dys2 immunoreactivity was found in the spine component of spine synapses. Particularly heavy label was observed on the postsynaptic densities. In the cerebral and cerebellar cortices all spines were immunopositive. In the hippocampus some postsynaptic densities were intensely immunostained, whereas those of adjacent synapses remained unstained. The findings suggest that dystrophin is an integral protein of the postsynaptic component of spine synapses but is lacking in a subpopulation of hippocampal spine synapses. The heterogeneity of input to the hippocampal spiny sites by contrast to the homogeneous population of fibres synapsing with cerebral and cerebellar cortical spines is suggested to account for differences.

In order to study structural alterations which occur after a defined unilateral cortical infarct, the hindlimb region of the rat cortex was photochemically lesioned. The infarcts caused edema restricted to the perilesional cortex which affected allocortical and isocortical areas differently. Postlesional changes in cytoskeletal marker proteins such as microtubule-associated protein 2, non-phosphorylated (SMI32) and phosphorylated (SMI35, SMI31 and 200,000 mol. wt) neurofilaments and 146,000 mol. wt glycoprotein Py as well as changes in proteoglycans visualized with Wisteria floribunda lectin binding (WFA) were studied at various time points and related to glial scar formation. The results obtained by the combination of these markers revealed six distinct regions in which transient, epitope-specific changes occurred: the core, demarcation zone, rim, perilesional cortex, ipsilateral thalamus and contralateral homotopic cortical area. Within the core immunoreactivity for microtubule-associated protein 2 and SMI32 decreased and the cellular components showed structural disintegration 4 h post lesion, but partial recovery of somatodendritic staining was seen after 24 h. Microtubule-associated protein 2 and SMI32 persisted up to days 7 and 5 respectively in the core, whereas the number of glial fibrillary acidic protein- and WFA-positive cells decreased between days 7 and 14. The demarcation zone showed a dramatic loss of immunoreactivity for all epitopes 4 h post lesion which was not followed by a phase of recovery. In the inner region of the demarcation zone there was an invasion and accumulation of non-neuronal WFA-positive cells which formed a tight capsule around the core. Neuronal immunoreactivities for microtubule-associated protein 2, SMI31 and Py as well as astrocytic glial fibrillary acidic protein increased strongly within an approximately 0.4-1.0 mm-wide rim region directly bordering the demarcation zone. Py immunoreactivity increased significantly in the perilesional cortex, whereas glial fibrillary acidic protein-positive astrocytes became transiently more numerous in the entire lesioned hemisphere including strongly enhanced immunoreactivity in the thalamus by days 5-7 post lesion. Glial fibrillary acidic protein immunoreactivity increased in the corpus callosum and the homotopic cortical area of the unlesioned hemisphere by days 5-7. In this homotopic area additional changes in SMI31 immunoreactivity occurred. Our results showed that a cortical infarct is not only a locally restricted lesion, but leads to a variety of cytoskeletal and other structural changes in widely-distributed functionally-related areas of the brain.

Vimentin contributes to the cytoskeleton of different cell-types, among them glial cells. We report here that different forms of this protein, distinguishable by the monoclonal antibodies Vim3B4 and V9, are species-specifically expressed in cultures of glial fibrillary acidic protein (GFAP) positive, primary astrocytes of the chicken and rat. Most cells in the cultures co-expressed GFAP and one of the two vimentin epitopes. The Vim3B4 positive epitope was present in chicken astrocytes, while the V9 positive was not. Inverse situation was found in the astrocytes of rat. In vitro age of the cells did not influence the hierarchy of vimentin epitope expression with respect to species-specificity. Our result shows that the different vimentin expression program of cultured astrocytes of the chicken and rat is preserved under in vitro conditions. The presented data support the concept of the species-specific regulation of vimentin forms in glial cells of the central nervous system.

Remote astroglial response was evoked in the adult rat visual cortex by unilateral destruction of the corpus geniculatum laterale. Homogenates of ipsi- and contralateral (operated and control) visual cortices were analysed by immunoblotting. A peak increase in glial fibrillary acidic protein (GFAP) was observed 2 weeks after lesion which then declined but did not return to normal showing a time course similar to that of previously observed immunohistochemical changes. Findings prove that the mechanism underlying the enhanced immunoreactivity during remote astroglial response is an up-regulation of GFAP synthesis in the astroglial processes surrounding degenerating synapses.

Microtubule-associated tau proteins are likely candidates to interfere with axonal transport of membranous organelles. We studied that tau proteins influenced the enzyme activity of kinesin, known to drive anterograd transport along microtubules. An in vitro reconstituted system was applied; microtubules were assembled from purified tubulin with or without tau proteins. Both types of reconstituted microtubules stimulated MgATPase activity of purified kinesin in a concentration dependent, saturable manner. The extent of maximal stimulation by tau-coated microtubules was lower than that of microtubules without tau proteins. Analysis of kinetic data, on the other hand, suggests that tau-coated microtubules apparently bind kinesin with higher affinity then microtubules not associated with tau proteins. Tau proteins, similarly to tubulin dimers, seem to bind to the heavy chain of kinesin. These data support the notion that tau proteins could act as regulators of kinesin-driven processes.

Two monoclonal antibodies directed against vimentin, Vim 3B4 and V9 could distinguish between vimentins originating from certain species, when tested on cell lines (Bohn et al, 1992). Our comparative immunohistochemical studies in the rat and chicken brain with the same antibodies suggest the coexistence of two vimentin forms in the glial cells of both species. One of these forms bearing the epitope present in the respective non-glial cell lines is present in astrocytes and Bergmann glia independently of the ontogenic state of the animal. The other epitope appeared also mutually in both species, albeit its expression was more restricted. These patterns suggest that in these two species, the expression of the different vimentin forms might be differently regulated.

Kinesin, a mechanochemical enzyme that translocates membranous organelles, was initially identified and purified from soluble extracts from vertebrate brains. However, immunocytochemical and morphological approaches have demonstrated that kinesin could be associated to intracellular membranous organelles. We used an antibody raised against the head portion of the Drosophila kinesin heavy chain to reveal the presence of this protein in membranous organelles from rat brain. By using differential centrifugation and immunoblotting we observed a 116 kDa protein that crossreacts with this antibody in microsomes, synaptic vesicles, and mitochondria. This protein could be extracted from mitochondria with low salt concentrations or ATP. The 116 kDa solubilized protein has been identified as conventional kinesin based on limited sequence analysis. We also show that a polyclonal antibody raised against mitochondria-associated kinesin recognizes soluble bovine brain kinesin. The soluble and mitochondrial membrane-associated kinesins show a different isoform pattern. These results are consistent with the idea that kinesin exists as multiple isoforms that might be differentially distributed within the cell. In addition digitonin fractionation of mitochondria combined with KI extraction revealed that kinesin is a peripheral protein, preferentially located in a cholesterol-free outer membrane domain; this domain has the features of contact points between the mitochondrial outer and inner membranes. The significance of these observations on the functional regulation of the mitochondria-associated kinesin is discussed.

In isolated, intact liver mitochondria from hyperthyroid rats, the L-glycerol-3-phosphate binding site(s) of the L-glycerol-3-phosphate dehydrogenase was (were) found to be influenced by the nature of the electron acceptor, as well as by the pH and the presence of calcium ions. With the hydrophobic electron acceptor menadione a single L-glycerol-3-phosphate binding site was detected kinetically at bulk pH values between 6.5 and 9.0. With the hydrophilic phenazine methosulfate, on the other hand, two L-glycerol-3-phosphate binding sites were distinguishable at pH > or = 7.5 and pH > or = 7.0, in the presence and absence of Ca2+, respectively. The kinetic mechanism of the reaction catalyzed by L-glycerol-3-phosphate dehydrogenase is ping pong Bi Bi with a hydrophilic electron acceptor, where as with the hydrophobic substance, a sequential Bi Bi mechanism was observed. We suggest that the latter mechanism has physiological relevance.

Clinical data of 70 patients, treated and observed with myelodysplastic syndrome between 1977 and 1989 were analysed. Two-thirds of the patients belonged to the elder age-group and a mild female predominance was registered. With the application of complex cytochemical-histological and cytogenetical methods, correct diagnosis could be established. The clinical material included patients from different morphologic subtypes: 19 with refractory anaemia (with a longer course of the illness). 20 with sideroblastic anaemia, 26 with chronic myelomonocytic leukaemia and the remaining 5 with refractory anaemia with excess of blasts (a more progressive type of the myelodysplastic syndrome, with a short duration). The mean survival of all patients were 42 months. 45 (69%) died during this period and 12 (18.5%) among them in acute myelogenous leukaemia (mean survival: 16 month). Megakaryoblastic leukaemic transformation was observed in three patients with sideroblastic refractory anaemia. Haemorrhage and infection-sepsis, due to thrombocytopenia and/or granulocytopenia, was fatal in 30 cases. In the treatment of the myelodysplastic syndrome an appropriate supportive therapy (blood transfusion, antibiotics) has a decisive importance. A more aggressive treatment with cytostatic drugs is suggested in the progressive form of the disease of younger patients and in patients with overt acute leukaemia.