Preparation of anti-inhibitor serum and its effect on the multiplication of influenza virus

Antiserum был подготовлен противингибитор вируса haemagglutination (IVH)одна из эмбриона chorioallantoic мембр анныепутем иммун изации морских св инокЭто анти-инги битора в сыворотке заблокирован ингибирование IVH из chorioallantoicмембран в haemagglutination испытанияно ника кого влияния на ре цепторы эритроци товСыворотке кро] ви не влияет рост chorioallantoic мембраны клет ок инет нейтрализ овать воздействи е на вирус гриппа Она снизилась спо собность chorioallantoic мембр ан для adsorb вируса гри ппа, а также степен ь размножения вир усав такого рода тканиАвторы хоте ли бы поблагодари ть г-н Г. Ruttkay-Ne -палубе и для проведения эле ктрофореза меру ния.     

Nefiracetam (DM-9384) reverses apomorphine-induced amnesia of a passive avoidance response: Delayed emergence of the memory retention effects

Nefiracetam is a novel pyrrolidone derivative which attenuates scopolamine-induced learning and post-training consolidation deficits. Given that apomorphine inhibits passive avoidance retention when given during training or in a defined 10–12h post-training period, we evaluated the ability of nefiracetam to attenuate amnesia induced by dopaminergic agonism. A step-down passive avoidance paradigm was employed and nefiracetam (3 mg/kg) and apomorphine (0.5 mg/kg) were given alone or in combination during training and at the 10–12h post-training period of consolidation. Co-administration of nefiracetam and apomorphine during training or 10h thereafter produced no significant anti-amnesic effect. However, administration of nefiracetam during training completely reversed the amnesia induced by apomorphine at the 10h post-training time and the converse was also true. These effects were not mediated by a dopaminergic mechanism as nefiracetam, at millimolar concentrations, failed to displace either [³H]SCH 23390 or [³H]spiperone binding from D₁ or D₂ dopamine receptor subtypes, respectively. It is suggested that nefiracetam augments molecular processes in the early stages of events which ultimately lead to consolidation of memory.     

Paleobiology of Etruscan populations

A research project on the population biology of ancient Etruscans has recently started. The aim of this multidisciplinary research is the anthropological definition of Etruscan populations, about which little is known. The study of the skeletal remains is expected to lead to the identification of characteristics typical of this group, which will be used to establish affinities and differences with other contemporary Italic populations, as well as with previous and subsequent groups. An outline of the project is presented here, together with an indication of the problems concerning the availability of material. A summary of previous research on Etruscans is also given. In the final section, preliminary results are presented on one aspect of the research presently under way, namely the odontometric study of different groups of Etruscan populations. These results suggest a homogeneity within the groups described under the common label “Etruscans”.     

Distribution of extracellular polysaccharides and flotation of anaerobic sludge

 Extracellular polysaccharides (EPS) were quantified in dense granules and loose flocs by chemical analysis of the uronic acid content. Their distribution within the aggregates was determined by microscopic staining. Granules contained a higher amount of EPS (1–1.6 mg/g volatile suspended solids, VSS) than flocs (0.3 mg/g VSS). In granules approximately 50% of the total amount of EPS was present in a 40-μm-thick zone on the surface. The remainder was dispersed in the rest of the aggregate. In flocs the highest concentration was present in the centre and the EPS layer on the surface was not found. Tests showed that flocculent sludge was very sensitive to flotation, while the studied granules did not float. The lower susceptibility to flotation of granules as compared to flocs was attributed to the presence of the hydrophilic EPS coating that prevents attachment of gas bubbles. Received: 21 November 1995/Received last revision: 15 April 1996/Accepted: 22 April 1996     

Sequencing of genes within the vir regulon of Streptococcus pyogenes type M15 — an opacity factor-positive serotype with low opacity factor expression

Major virulence determinants of group A streptococci, such as M-protein, immunoglobulin Fc-receptors (FcRA, EmmL) and C5a peptidase, appear to be genetically co-regulated, their genes being located within a vir regulon. We studied the organization of these genes in a group A, type M15 strain of Streptococcus pyogenes, previously defined as OF^?, by hybridization analysis of chromosomal DNA and of an S. pyogenes gene library in Escherichia coli, and by gene sequencing. Within the vir regulon, in addition to the virR and scpA genes, three so-called emm-related genes were found: fcrA, emmL and enn. Whereas IgG Fc-binding proteins were encoded by fcrA and emmL, the product of enn was not identified. The presence of three emm-related genes in this region is reminescent of vir regulon organization in OF⁺ rather than OF^? strains as earlier defined by others. Furthermore, analysis of the deduced product of the emmL gene showed deletions and amino acid substitutions within the PGTS-rich domain and membrane anchor, which thus resembles corresponding products of OF⁺ rather than OF^? strains. In view of these findings, the opacity factor (OF) activity of the strain was tested using growth supernatant, with negative outcome. However, a concentrated SDS cell extract revealed definite OF activity. One of two other type M15 reference strains also showed definite OF activity in SDS extracts. We therefore propose that type M15 strains belong to the OF⁺ category but often show low levels of expression of OF.     

Cloning and comparative mapping of a gene from the commonly deleted region of DiGeorge and Velocardiofacial syndromes conserved in C. elegans

We have identified and cloned a gene, ES2, encoding a putative 476 amino acid protein with a predicted M _r of 52,568. The gene is localized within the DiGeorge/Velocardiofacial syndrome locus on 22q11.2 and is deleted in all the patients in which a deletion within 22q11 could be demonstrated, with the exception of one patient. ES2 is expressed in all the tissues studied. Sequence comparison showed identity with five ESTs and at the amino acid level the sequence was highly similar to, and collinear with, a hypothetical C. elegans protein of unknown function. Mutation analysis was performed in 16 patients without deletion, but no mutation has been found. The cDNA sequence is conserved in mouse and is localized on MMU16B1-B3, known to contain a syntenic group in common with HSA 22q11.2. Received: 25 March 1996 / Accepted: 15 May 1996     

A method for introducing site-specific mutations using oligonucleotide primers and its application to site-saturation mutagenesis

Oligonucleotide primer-directed mutagenesis is a useful molecular biological tool, which is invalubable for the study of the structure/function relationships in proteins and for the creation of mutant proteins possessing modified or novel biological activities. Mutagenesis studies in which a site-saturation approach is employed require a high-efficiency mutagenesis procedure, which will generate a population of mutated molecules containing an even distribution of all possible amino acid changes, or a subset thereof. This article describes such a mutagenesis technique and discusses the adaptations that are necessary to perform sitesaturation mutagenesis.