Polysilanes fonctionnels, 3. Synthèse d'α,ω-bis(triméthylsilyl)oligo(méthylphénylsilane)s précurseurs des α,ω-bis(triméthylsilyl)oligo(chlorométhyl-silane)s. Charactérisation des heptaméthyl phényl-2 trisilane et octaméthyl diphényl-2,3 tétrasilane

Low-molecular-weight organosilane polymers were prepared by sodium coupling of dichloro-methylphenylsilane ( 1 ) with chlorotrimethylsilane ( 2 ). Gel permeation chromatography (GPC), IR and NMR (¹H, ¹³C and ²⁹Si) analysis of the crude product ( 3 ) were performed and compared with those of the isolated first oligomers, trisilane ( 3a ) and tetrasilane ( 3b ). The GPC characteristics, especially high resolution ones, in accordance with the α,ω-bis(trimethylsilyl)-oligo(methylphenylsilane) structure are compared with those of hydrocarbon polymers. The relations of the NMR characteristics of the methylphenylsilanediyl unit with the position along the chain and the configuration of the diads are approached. Some spectroscopic indications of the secondary structure are discussed.     

CHARGE syndrome: developmental and behavioral data

Kabuki syndrome (KS) is associated with multiple organ system involvement. Characteristic features include long palpebral fissures with everted lower lids, prominent ears, skeletal abnormalities, mental retardation, and short stature. An increased incidence of infection has been reported in KS, and a few patients have been noted to have immune defects. However, the frequency and severity of the immune deficiency has not been clearly defined. Immunologic evaluation of 19 consecutive individuals with KS was performed at The Children's Hospital of Philadelphia. Decreased IgA levels were noted in 15/19 individuals (79%), 2 of whom had undetectable levels. Eight patients (42%) also had low total IgG levels. Specific IgG subclass abnormalities were found in 6 of 13 patients evaluated. IgM levels were less frequently decreased. One patient failed to generate anti-tetanus antibodies despite immunization. This study suggests that hypogammaglobulinemia is a frequent finding in children with KS. The pattern of antibody abnormalities seen in children with KS resembles common variable immune deficiency (CVID). Due to this increased susceptibility to infection, children with KS should have immunologic evaluations at the time of diagnosis in order to reduce preventable morbidity and mortality.     

Post traumatic brain perfusion SPECT analysis using reconstructed ROI maps of radioactive microsphere derived cerebral blood flow and statistical parametric mapping

Background  

Assessment of cerebral blood flow (CBF) by SPECT could be important in the management of patients with severe traumatic brain injury (TBI) because changes in regional CBF can affect outcome by promoting edema formation and intracranial pressure elevation (with cerebral hyperemia), or by causing secondary ischemic injury including post-traumatic stroke. The purpose of this study was to establish an improved method for evaluating regional CBF changes after TBI in piglets.     

Immune response induction and new effector mechanisms possibly involved in protection conferred by the Cuban anti-meningococcal BC vaccine

This report explores the participation of some afferent mechanisms in the immune response induced by the Cuban anti-meningococcal vaccine VA-MENGOC-BC. The induction of delayed-type hypersensitivity in nursing babies and lymphocyte proliferation after immunization is demonstrated. The presence of gamma interferon IFN-gamma and interleukin-2 (IL-2) mRNAs but absence of IL-4, IL-5, and IL-10 mRNAs were observed in peripheral blood mononuclear cells from immunized subjects after in vitro challenge with outer membrane vesicles. In addition, some effector functions were also explored. The presence of opsonic activity was demonstrated in sera from vaccinees. The role of neutrophils as essential effector cells was shown. In conclusion, we have shown that, at least in the Cuban adult population, VA-MENGOC-BC induces mechanisms with a T-helper 1 pattern in the afferent and effector branches of the immune response.     

Mast cell myositis: a new feature of allergic asthma?

There is some evidence that, in asthma, mast cells infiltrate the airway smooth muscle layer and, as a consequence, alter the functional and structural properties of myocytes. This inflammation so-called mast-cell myositis, probably contributes to both bronchial hyperresponsiveness and airway remodelling. Previous observations have pointed out the presence of mast cells within airway smooth muscle of atopic patients and recent data obtained in asthmatic patients demonstrate that this infiltration is more important in asthmatic patients with atopy. Although the mechanism of such a mast cell attraction remains to be fully understood, experimental data demonstrate that, upon stimulation by tryptase or cytokines, smooth muscle cells can attract mast cells through the production of TGF-beta1 or SCF. Once at the site of inflammation, activated mast cells are responsible for an important extracellular deposition of inflammatory products that may facilitate the increase in smooth muscle mass. In addition, comparison of asthmatic patients with and without atopy suggests that mast cell myositis is closely related with atopy.     

DNA polymerase gene locus of <Emphasis Type="Italic">Cercopithecine herpesvirus 1</Emphasis> is a suitable target for specific and rapid identification of viral infection by PCR technology

The family Herpesviridae comprises at least 100 herpesviruses. Numerous human and animal pathogenic herpesviruses have been identified so far, including Cercopithecine herpesvirus 1 (CeHV-1). This virus is a member of the subfamily Alphaherpesvirinae and is the most hazardous herpesvirus to man. CeHV-1 is also known as B-virus or monkey B virus and as Herpesvirus simiae. In order to gain more genetic information, the viral DNA polymerase (DPOL) gene was identified using polymerase chain reaction (PCR) and DNA nucleotide sequence analysis. The deduced amino acid sequence contains the motifs and signatures that are typical for the B-family of DPOLs. The DPOL gene of CeHV-1 was found to be a suitable target for the specific and rapid identification of the Cercopithecine herpesvirus 1 infection by PCR technology. Comparative analysis of the DNA sequences of the DPOL gene loci of CeHV-1, Human herpesvirus 1 and 2 (HHV-1 and HHV-2), and other herpesviruses was carried out for determination of unique genomic regions of the individual DPOL genes. A primer set of 12 primers was used for screening the DNA of CeHV-1, HHV-1, and HHV-2 by detailed PCR. It was found that six out of twelve primer combinations are able to detect specifically the CeHV-1 genome without cross reactivity with the genome of HHV-1 and/or HHV-2. The specificity of the individual amplified DNA fragments was confirmed by DNA nucleotide sequence analysis. The results of these studies indicate that the six primer combinations of the specific CeHV-1 DPOL primer set is the method of choice for a rapid, precise and specific identification of a CeHV-1 infection by PCR. Due to the fact that this specific CeHV-1 DPOL primer set does not amplify any DNAs of HHV-1 or HHV-2 genome this technology is stressing and can be successfully used unlimited and more credible in all laboratories with PCR technical facility routinely for detection of a CeHV-1 infection in vivo or in vitro.The GenBank Accession No. of the sequence of DNA polymerase gene of Cercopithecine herpesvirus 1 (CeHV-1) reported in this study is AY568415, DPOL protein ID AAT67222; nuclear phosphoprotein ID AAT67223     

Theta coupling in the human electroencephalogram during a working memory task

The role of coupling between prefrontal and temporo-parietal brain areas within the theta frequency range of the human electroencephalogram was explored in a working memory task. During encoding of visual information higher theta amplitudes were observed in the right compared to the left hemisphere. Retrieval of visuospatial and verbal information elicited a more bilateral activation pattern. These effects were accompanied by theta coupling between dorsolateral prefrontal and right posterior temporal electrode sites during encoding. During retrieval prefrontal and bilateral temporo-parietal brain areas were coupled. These results support the idea of working memory functions being dependent on distributed prefrontal-temporal networks.     

Immunohistochemical characterization of fibroblast subpopulations in normal peritoneal tissue and in peritoneal dialysis-induced fibrosis

Peritoneal fibrosis is one of the most common morphological changes observed in continuous ambulatory peritoneal dialysis (CAPD) patients. Both resident fibroblasts and new fibroblast-like cells derived from the mesothelium by epithelial-to-mesenchymal transition are the main cells involved fibrogenesis. In order to establish markers of peritoneal impairment and pathogenic clues to explain the fibrogenic process, we conducted an immunohistochemical study focused on peritoneal fibroblasts. Parietal peritoneal biopsies were collected from four patient groups: normal controls (n=15), non-CAPD uremic patients (n=17), uremic patients on CAPD (n=27) and non-renal patients with inguinal hernia (n=12). To study myofibroblastic conversion of mesothelial cells, -smooth muscle actin (SMA), desmin, cytokeratins and E-cadherin were analyzed. The expression of CD34 by fibroblasts was also analyzed. Fibroblasts from controls and non-CAPD uremic patients showed expression of CD34, but no myofibroblastic or mesothelial markers. The opposite pattern was present during CAPD-related fibrosis. Expression of cytokeratins and E-cadherin by fibroblast-like cells and -SMA by mesothelial and stromal cells supports that mesothelial-to-myofibroblast transition occurs during CAPD. Loss of CD34 expression correlated with the degree of peritoneal fibrosis. The immunophenotype of fibroblasts varies during the progression of fibrosis. Myofibroblasts seem to derive from both activation of resident fibroblasts and local conversion of mesothelial cells.Manuel López-Cabrera and Rafael Selgas contributed equally to the article.     

Evaluation of the COBAS TaqMan 48 real-time PCR system for quantitation of hepatitis B virus DNA

The purpose of this study is to evaluate the usefulness of the new real-time PCR COBAS TaqMan 48 analyzer, comparing it to the existing COBAS AMPLICOR HBV MONITOR based on conventional PCR technology. The study used 104 samples from different patients. No differences were found in the sensitivity of the tests. There was an excellent correlation between the sample with a viral load within the dynamic range of the two tests (r = 0.938). The COBAS TaqMan test has a wider linear range, and this fact enables quantifying of the viral load without diluting the sample.     

ECT and Anticoagulation

Electroconvulsive therapy (ECT) is an effective and safe treatment for depression. Anticoagulation therapy is used to reduce morbidity or mortality from stroke or recurrent pulmonary embolus in various cardiac and vascular conditions. We report in detail the successful ECT treatment of a patient suffering from major depression with psychotic features who continued warfarin (Coumadin) anticoagulant therapy.