Trainmasters or Easyjet pilots? Historical production,labor organizing,and the Spanish engine drivers’ union

This article presents an analysis of the relationship between historical memory and the emergence and reproduction of a specific model of unionism. I argue that in order to understand the militant particularism of the Spanish engine drivers, we need to look at the historical representations that it is embedded in. Recourse to a generational framework makes possible the sustained presentation of the union as a case of successful workers’ organizing, in spite of evidence to the contrary. The historical ethnographic analysis of SEMAF, the Spanish engine drivers’ union, contributes to the analysis of historical memory within the contemporary anthropology of class. The article contributes to theoretical debates in the anthropology of class by reclaiming Michel Trouillot’s conceptualization of the historical process. Two aspects of Trouillot’s work are singled out: his dynamic understanding of the process of historical production and the corollary formulation of the overlapping capacities in which people participate in it (as agents, actors, and subjects) and his emphasis on the importance of expanding scholarly views of the field of historical production.     

Effects of cytochalasins on lymphocytes: mechanism of inhibition of rosette formation

The mechanisms operative in the inhibition by cytochalasins of human peripheral blood T lymphocytic rosette formation with sheep erythrocytes remain obscure in the light of the multiplicity of biologic effects of cytochalasins. Moreover, we have shown the existence of three distinct classes of cytochalasin-binding sites (H-, M-, and L-sites) in such lymphocytes (J. Biol. Chem. 256:1290-1300, 1981). We have, therefore, explored the mechanism of rosette inhibition and present evidence that shows: a) Inhibition of rosetting is not caused by inhibition of glucose transport in lymphocytes; b) cytochalasin binding to the H- and M-sites, both integral plasma membrane proteins, is not involved in the effect; c) nonspecific partitioning of cytochalasins in the plasma membrane lipids of lymphocytes appears unlikely to explain the effect; d) evidence presented in this paper strongly suggests that cytochalasin binding to the actin associated L-site mediates the inhibition of rosetting. We conclude that cytoskeletal microfilaments play a critical role in the normal functioning of cell surface receptors for binding to sheep erythrocytes.     

Control of the pericentrosomal H2O2 level by peroxiredoxin I is critical for mitotic progression

Proteins associated with the centrosome play key roles in mitotic progression in mammalian cells. The activity of Cdk1-opposing phosphatases at the centrosome must be inhibited during early mitosis to prevent premature dephosphorylation of Cdh1—an activator of the ubiquitin ligase anaphase-promoting complex/cyclosome—and the consequent premature degradation of mitotic activators. In this paper, we show that reversible oxidative inactivation of centrosome-bound protein phosphatases such as Cdc14B by H₂O₂ is likely responsible for this inhibition. The intracellular concentration of H₂O₂ increases as the cell cycle progresses. Whereas the centrosome is shielded from H₂O₂ through its association with the H₂O₂-eliminating enzyme peroxiredoxin I (PrxI) during interphase, the centrosome-associated PrxI is selectively inactivated through phosphorylation by Cdk1 during early mitosis, thereby exposing the centrosome to H₂O₂ and facilitating inactivation of centrosome-bound phosphatases. Dephosphorylation of PrxI by okadaic acid–sensitive phosphatases during late mitosis again shields the centrosome from H₂O₂ and thereby allows the reactivation of Cdk1-opposing phosphatases at the organelle.     

Fish Gut Microbiome: Current Approaches and Future Perspectives

In recent years, investigations of microbial flora associated with fish gut have deepened our knowledge of the complex interactions occurring between microbes and host fish. The gut microbiome not only reinforces the digestive and immune systems in fish but is itself shaped by several host-associated factors. Unfortunately, in the past, majority of studies have focused upon the structure of fish gut microbiome providing little knowledge of effects of these factors distinctively and the immense functional potential of the gut microbiome. In this review, we have highlighted the recently gained insights into the diversity and functions of the fish gut microbiome. We have also delved on the current approaches that are being employed to study the fish gut microbiome with an aim to collate all the knowledge gained and make accurate conclusions for their application based perspectives. The literature reviewed indicated that the future research should shift towards functional microbiomics to improve the maximum sustainable yield in aquaculture.     

Applications of self-organizing map for patterning macrofungal diversity of xerothermic swards

Macrofungal communities were investigated in four associations of xerothermic swards: Festucetum pallentis, Origano-Brachypodietum, Adonido-Brachypodietum pinnati and Diantho-Armerietum elongatae in a Jurassic area of the Częstochowa Upland (southern Poland). A total of 47 species were recorded. The self-organising map (SOM)—an unsupervised algorithm for artificial neural networks—was used to recognise patterns in the macrofungal communities of diverse xerothermic swards. Only two associations were mycologically similar: Origano-Brachypodietum and Adonido-Brachypodietum pinnati. Species with high and significant IndVal (the species indicator value) for each investigated phytocoenoses are presented. The presence of macrofungal species and the participation of indicator species were connected with habitat factors of plant associations, as documented by the IndVal application. In the least fertile phytocoenoses, macrofungal communities were poor with few indicator species. The more fertile phytocoenoses had richer and more varied communities of macrofungi with higher numbers of indicator species. The ordering methods applied in this study were very effective for analyzing the macrofungal communities existing in plant associations.     

Titanium and iron titanium oxide nanoparticles in antennae of the migratory ant <Emphasis Type="Italic">Pachycondyla marginata</Emphasis>: an alternative magnetic sensor for magnetoreception?

The most accepted hypothesis of magnetoreception for social insects is the ferromagnetic hypothesis which assumes the presence of magnetic material as a sensor coupled to sensitive structures that transmit the geomagnetic field information to the nervous system. As magnetite is the most common magnetic material observed in living beings, it has been suggested as basic constituent of the magnetoreception system. Antennae and head have been pointed as possible magnetosensor organs in social insects as ants, bees and termites. Samples of three antenna joints: head-scape, scape-pedicel and pedicel-third segment joints were embedded in epoxi resin, ultrathin sectioned and analyzed by transmission electron microscopy. Selected area electron diffraction patterns and X-ray energy dispersive spectroscopy were obtained to identify the nanoparticle compound. Besides iron oxides, for the first time, nanoparticles containing titanium have been identified surrounded by tissue in the antennae of ants. Given their dimension and related magnetic characteristics, these nanoparticles are discussed as being part of the magnetosensor system.     

Iron modulates the activity of monoamine oxidase B in SH-SY5Y cells

Both monoamine oxidase B (MAO-B) and iron accumulation are associated with neurologic diseases including Parkinson’s disease. However, the association of iron with MAO-B activity was poorly understood. Here we took advantage of highly sensitive and specific fluorescence probes to examine the change in MAO-B activity in human dopaminergic neuroblastoma (SH-SY5Y) cells upon iron exposure. Both ferric and ferrous ions could significantly enhance the activity of MAO-B, instead of MAO-A, in SH-SY5Y cells. In addition, iron-induced increase in MAO-B probe fluorescence could be prevented by pargyline and other newly developed MAO-B inhibitors, suggesting that it was MAO-B activity-dependent. These findings may suggest MAO-B is an important sensor in iron-stressed neuronal cells.     

Bacterial Artificial Chromosomes: A Functional Genomics Tool for the Study of Positive-strand RNA Viruses

Reverse genetics, an approach to rescue infectious virus entirely from a cloned cDNA, has revolutionized the field of positive-strand RNA viruses, whose genomes have the same polarity as cellular mRNA. The cDNA-based reverse genetics system is a seminal method that enables direct manipulation of the viral genomic RNA, thereby generating recombinant viruses for molecular and genetic studies of both viral RNA elements and gene products in viral replication and pathogenesis. It also provides a valuable platform that allows the development of genetically defined vaccines and viral vectors for the delivery of foreign genes. For many positive-strand RNA viruses such as Japanese encephalitis virus (JEV), however, the cloned cDNAs are unstable, posing a major obstacle to the construction and propagation of the functional cDNA. Here, the present report describes the strategic considerations in creating and amplifying a genetically stable full-length infectious JEV cDNA as a bacterial artificial chromosome (BAC) using the following general experimental procedures: viral RNA isolation, cDNA synthesis, cDNA subcloning and modification, assembly of a full-length cDNA, cDNA linearization, in vitro RNA synthesis, and virus recovery. This protocol provides a general methodology applicable to cloning full-length cDNA for a range of positive-strand RNA viruses, particularly those with a genome of >10 kb in length, into a BAC vector, from which infectious RNAs can be transcribed in vitro with a bacteriophage RNA polymerase.     

Giant viruses,giant chimeras: The multiple evolutionary histories of Mimivirus genes

Background  

Although capable to evolve, viruses are generally considered non-living entities because they are acellular and devoid of metabolism. However, the recent publication of the genome sequence of the Mimivirus, a giant virus that parasitises amoebas, strengthened the idea that viruses should be included in the tree of life. In fact, the first phylogenetic analyses of a few Mimivirus genes that are also present in cellular lineages suggested that it could define an independent branch in the tree of life in addition to the three domains, Bacteria, Archaea and Eucarya.     

The origin of a novel gene through overprinting in <Emphasis Type="Italic">Escherichia coli</Emphasis>

Background  

Overlapped genes originate by a) loss of a stop codon among contiguous genes coded in different frames; b) shift to an upstream initiation codon of one of the contiguous genes; or c) by overprinting, whereby a novel open reading frame originates through point mutation inside an existing gene. Although overlapped genes are common in viruses, it is not clear whether overprinting has led to new genes in prokaryotes.