Interpretation of antitoxoplasma antibody findings

Between reactions assessing one class of immunoglobulins and reactions detecting all serum immunoglobulins comprehensively such as CFT, there is, as might be expected, a very poor quantitative correlation and thus in individual sera the result of one reaction cannot be reliably added to the result of another (CFT:ELISA/IgG). Even the correlation between reactions focused on the same Ig class (ELISA/IgG: IFT/IgG) is no better. Among reactions assessing specific IgM we consider ELISA/IgM better than IFT/IgM because there is not the risk of false negativity caused by concurrence of IgG. A combination of ELISA/IgG and ELISA/IgM gives good results as a statistical group: the distribution of results revealed agglomerations of sera corresponding to the assumed age of the infection derived from the generally accepted pattern of antibody formation. The applicability of the combination of these two reactions alone for evaluation of individual sera is a promising procedure but awaits further confirmation. Long-term investigations revealed within two years after infection a marked decline of CFT antibodies in the majority of cases but it was not sufficiently clear in ELISA/IgG. Despite the technical advantages of ELISA reactions, elimination af the CFT reaction is not foreseen in the near future. As the minimal combination of methods which provides adequate information we may consider at the present time CFT for assessment of total antibodies and ELISA/IgM for more marked differentiation of the acute stage. Evaluation of the lowest CFR titres considered hitherto as "practically negative" must be obviously revised in subjects with immunosuppression and organ donors for transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Clozapine-induced cholestatic jaundice: a case report

We report on a patient who became jaundiced during treatment with clozapine (Leponex). Histologically, cholestatic hepatitis with single-cell necroses of hepatocytes and infiltration of the portal zones with eosinophilic granulocytes were found. The patient recovered after discontinuation of clozapine, and liver function tests returned to normal within 4 weeks. This adverse effect of clozapine suggests that this "atypical" tricyclic neuroleptic resembles the phenothiazines both with regard to therapeutic spectrum and side effects.     

Auditory evoked potentials to tones and syllables in adults: evidence of specific influence on N250 wave

Brain-derived neurotrophic factor (BDNF) is involved in the differentiation and the survival of neurons. It has also been shown to be associated with the regrowth of neurons of damaged spinal cord and the modulation of ionic currents by acting on sodium channels and NMDA receptors through tyrosine kinase B (TrkB) receptors. We investigated the effects of BDNF on rhythm generation induced by disinhibition in dissociated cultures from embryonic rat spinal cord (E14), with extracellular multisite recordings (MultiElectrode Arrays, MEAs) or intracellular patch-clamp recordings. Exogenous BDNF had only minor effects on the bursting by increasing the activity during the burst. This increase of activity is suggested to be mediated by a potentiation of the postsynaptic NMDA receptors because it has been found that BDNF potentiates the NMDA-evoked depolarization in cultures incubated with BDNF for 10 min. Possible direct effects of BDNF on sodium channels were also investigated by local application of BDNF to the soma of patched neurons but no depolarization was observed. Long-term application of BDNF strongly decreased the activity during the burst and also the number of active electrodes, possibly due to a decrease in network density.     

An AscI boundary library for the studies of genetic and epigenetic alterations in CpG islands

Knudson's two-hit hypothesis postulates that genetic alterations in both alleles are required for the inactivation of tumor-suppressor genes. Genetic alterations include small or large deletions and mutations. Over the past years, it has become clear that epigenetic alterations such as DNA methylation are additional mechanisms for gene silencing. Restriction Landmark Genomic Scanning (RLGS) is a two-dimensional gel electrophoresis that assesses the methylation status of thousands of CpG islands. RLGS has been applied successfully to scan cancer genomes for aberrant DNA methylation patterns. So far, the majority of this work was done using NotI as the restriction landmark site. Here, we describe the development of RLGS using AscI as the restriction landmark site for genome-wide scans of cancer genomes. The availability of AscI as a restriction landmark for RLGS allows for scanning almost twice as many CpG islands in the human genome compared with using NotI only. We describe the development of an AscI-EcoRV boundary library that supports the cloning of novel methylated genes. Feasibility of this system is shown in three tumor types, medulloblastomas, lung cancers, and head and neck cancers. We report the cloning of 178 AscI RLGS fragments via two methods by use of this library.     

Comparative usage of herpesvirus entry mediator A and nectin-1 by laboratory strains and clinical isolates of herpes simplex virus

The herpesvirus entry mediator A (HVEM/HveA) and nectin-1 (HveC/CD111) are two major receptors for herpes simplex virus (HSV). Although structurally unrelated, both receptors can independently mediate entry of wild-type (wt) HSV-1 and HSV-2 by interacting with the viral envelope glycoprotein D (gD). Laboratory strains with defined mutations in gD (e.g. rid1) do not use HVEM but use nectin-2 (HveB/CD112) for entry. The relative usage of HVEM and nectin-1 during HSV infection in vivo is not known. In the absence of a defined in vivo model, we used in vitro approaches to address this question. First, we screened HSV clinical isolates from various origins for receptor tropism and found that all used both HVEM and nectin-1. Second, we determined the numbers of surface receptors on various susceptible and resistant cell lines as well as on primary fibroblasts derived from an individual with cleft lip/palate ectodermal dysplasia (CLPED1). Although CLPED1 cells can only express a defective form of nectin-1, they allowed entry of wild type and mutant HSV strains by usage of either HVEM or nectin-2. Finally, we compared the ability of HVEM and nectin-1 to mediate entry when expressed at varying cell surface densities. Both receptors showed a direct relationship between the number of receptors and HSV susceptibility. Direct comparison of receptors suggests that nectin-1 is more efficient at promoting entry than HVEM. Overall, our data suggest that both receptors play a role during HSV infection in vivo and that both are highly efficient even at low levels of expression.     

New copolymethacrylates with azo-chromophores in the side chain

The synthesis and characterization of new poly({6-[4-(4-cyanophenylcarbamoyl)phenoxy]hexyl methacrylate}-co-{6-[4-(4- cyanophenylazo)phenoxy]hexyl methacrylate}) are reported. Their liquid-crystalline properties are investigated using differential scanning calorimetry, polarizing microscopy and X-ray diffraction techniques. The glass transition temperatures and the clearing points can be influenced by variation of the copolymer composition. The substances offer a relatively broad temperature range of mesomorphic properties suitable for photochemical studies.     

MECP2 duplication syndrome in a patient from Cameroon

MECP2 duplication syndrome (MDS; OMIM 300260) is an X‐linked neurodevelopmental disorder caused by nonrecurrent duplications of the Xq28 region involving the gene methyl‐CpG‐binding protein 2 (MECP2; OMIM 300005). The core phenotype of affected individuals includes infantile hypotonia, severe intellectual disability, very poor‐to‐absent speech, progressive spasticity, seizures, and recurrent infections. The condition is 100% penetrant in males, with observed variability in phenotypic expression within and between families. Features of MDS in individuals of African descent are not well known. Here, we describe a male patient from Cameroon, with MDS caused by an inherited 610 kb microduplication of Xq28 encompassing the genes MECP2, IRAK1, L1CAM, and SLC6A8. This report supplements the public data on MDS and contributes by highlighting the phenotype of this condition in affected individuals of African descent.     

Superficial angiomyxoma: report of four cases, including two subungueal tumors

We report four cases of superficial angiomyxomas, including two cutaneous tumors and two subungueal tumors. Histological analysis revealed a recently described tumor, so called superficial angiomyxoma. This is a myxoid paucicellular tumor lobulated and poorly circumbscribed, containing numerous small blood vessels surrounded by a mixed inflammatory cell infiltrate with notable neutrophils. Those tumors are positive for CD34. The differential diagnosis includes myxoid neurothecoma, myxoid neurofibroma and, for ungueal tumors, superficial acral fibromyxoma.