GATA-1 as a Regulator of Mast Cell Differentiation Revealed by the Phenotype of the GATA-1low Mouse Mutant

Here it is shown that the phenotype of adult mice lacking the first enhancer (DNA hypersensitive site I) and the distal promoter of the GATA-1 gene (neoΔHS or GATA-1low mutants) reveals defects in mast cell development. These include the presence of morphologically abnormal alcian blue+ mast cells and apoptotic metachromatic− mast cell precursors in connective tissues and peritoneal lavage and numerous (60–70% of all the progenitors) “unique” trilineage cells committed to erythroid, megakaryocytic, and mast pathways in the bone marrow and spleen. These abnormalities, which were mirrored by impaired mast differentiation in vitro, were reversed by retroviral-mediated expression of GATA-1 cDNA. These data indicate an essential role for GATA-1 in mast cell differentiation

Individually ventilated cages – Microbiological containment testing

Modern biomedical research projects need “high quality” laboratory animals in order to obtain repeatability and homogeneity of the experimental data and to reduce the number of animals. It is, thus necessary to use animals standardised with respect to genetic, microbiological and pathological conditions. Environmental control, by eliminating the chemical, physical and microbial contaminants, can guarantee more standardised housing conditions and, at the same time, highly reduce the biological risk for the personnel working with the animals in accordance with the European and Italian legislation. Among the physical parameters temperature and humidity have to be considered the most important for their influence on animal behavior and metabolism. The optimal values for temperature range between 20 and 23 °C and for humidity between 40 and 60 %; in fact it has been widely demonstrated that when these two parameters are too high, they enhance the growth of moulds and the life span of microorganisms and that most bacteria and fungi, that colonize man and animals, grow at temperatures between 25 and 40 °C.Microbiological quality assurance of laboratory animals aims to produce animals that meet requirements for microbiological quality, and to maintain the same quality throughout the experiment. Outbreaks of infectious disease in laboratory animals have to a great extent adversely affected their use in biomedical research. Some microorganisms occurring in laboratory animals can also affect man (zoonosis) and this risk is also present in animals which are used as a source of sera and vaccines for use in man. Due to the introduction of specified pathogen free (SPF) animals outbreaks of infectious diseases have been in part replaced by more subtle microbial interference in the outcome of animal experiments. Plenty of viruses, mycoplasma, bacteria and parasites that may affect biomedical research exist for all laboratory animal species (Boot, 1996).The Service for Quality and Assurance of Animal Experimentation routinely controls the animal housing environment. For several years it has been focusing its activity on monitoring microbiological conditions and even in the animal housing it has considered the indication of Whittard (Table 1), as acceptable levels of contamination. With regard to this problem we have analyzed the count of environmental microorganisms in the animal facility rooms and the isolating capacity of a ventilated cage system (IVC, Techniplast Gazzada, Varese, Italy) which has been conceived to protect, by filtering the supply and exhaust circulating air, both the housed animals and the working personnel. The experiment has been performed in a conventional animal facility to verify the possibility to use animals in mixed conditions i.e. animals housed in normal conditions and animals housed in IVC

Struttura, meccanismo d'azione ed effetti terapeutici di una nuova famiglia di antiparassitari: le avermectine

Consiglio Nazionale delle Ricerche, Biblioteca Centrale, P.le Aldo Moro, 7, ROMA (Italia) / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

Identification of differentially expressed genes induced by ozone stress in sensitive and tolerant poplar hybrids

The differential expression of genes induced by an acute ozone treatment was analysed in two poplar clones, i.e. Populus deltoides x maximowiczii, Eridano clone, and Populus x euoramericana, I-214 clone, respectively, sensitive and tolerant to this pollutant, performing suppression subtractive hybridization (SSH). From the obtained cDNA libraries several clones were obtained, which corresponded to differentially regulated genes. Preliminary expression analyses of four genes, Fs23ALRP, Ft33B-CaBP, Ft312B-WRKY, and Ft32C-WAK identified by the primary screening, were conducted by semi-quantitative RT-PCR to evaluate the ozone responsiveness of the libraries. The most interesting finding is the co-activation of a wall associated kinase and a WRKY transcription factor in response to O3 stress

Ozone-modulated genes in Populus spp.: identification of up- and down-regulated genes upon acute ozone exposure

During the last three decades, concentration of ozone in the lower troposphere of the Northern hemisphere has increased considerably. In many regions of the world there is an incontrovertible evidence that O3 levels are high enough to reduce crop yields, to cause shift in the genetic composition of natural and seminatural vegetation and to contribute to forest decline. These data explain the interest towards the damaging action of this pollutant on plants, particularly on molecular mechanisms, which are the basis of this kind of stress. An expression profile of genes up- and down-regulated by an acute ozone treatment (a single pulse of 150 ppb for five hours) in two hybrid poplar clones (Populus deltoides x maximowiczii, Eridano clone, and Populus x euoramericana, I-214 clone, sensitive and tolerant to O3, respectively) was obtained by sequencing 42 PCR clones belonging to four subtractive cDNA libraries obtained using suppression subtractive hybridisation (SSH). With the information gathered from different databases we were able to identify and assign a putative function to 31% of sequenced clones. The remain clones, classified as unknown, have presented an insufficient nucleotidic or deduced amino acidic similarity to proteins and/or genes of known function. Some of identified sequences presented high similarity with genes related to ozone stress already described in other species. Most of differentially expressed cDNA sequences can be classified as rarely transcribed. Indeed, almost half of the known sequences presented a meaningful similarity with genes not associated to ozone stress so far. Expression analysis of several sequenced up-regulated cDNA clones with known identity have showed that the level of all analyzed transcripts was increased by ozone treatment in both tolerant and sensitive poplar clones. By contrast, wall associated kinase (Ft32C clone) was induced by ozone stress in I-214 clone only. The Ft35A clone, isolated in I-214 poplar clone, was identified on the basis of high sequence similarity to Arabidopsis thaliana cytoplasmic ascorbate peroxidase (APX) cs1. This kind of APX result up-regulated by acute ozone treatment in tolerant poplar. By contrast, the cytosolic APX cs2, isolated by RT-PCR, was not induced by ozone treatment neither in tolerant nor in sensitive poplar clones

Verticillium wilt of Ailanthus altissima in Italy caused by V. dahliae: new outbreaks from Tuscany

Verticillium spp., including V. nonalfalfae and V. dahliae, are known vascular wilt pathogens of the invasive Ailanthus altissima (tree-of-heaven) in the United States and in Europe. Herein we provide evidence of the presence of a previously unreported wilt disease of A. altissima in Tuscany (Central Italy). Several isolates were collected from two locations and identified as V. dahliae, based on microscopical features of conidiophores, conidia and microsclerotia. Genomic DNA was extracted from the mycelium, the ITS region was amplified and the sequence was deposited in GenBank as VdGL16 (accession no. MK474459). BLASTn analysis showed 100% similarity with V. dahliae. To confirm pathogenicity of VdGL16, inoculations of Ailanthus seedlings were performed with the root dipping technique whereas mature trees were stem-inoculated. All inoculated seedlings exhibited wilt symptoms after 20 days, while mature Ailanthus trees showed wilting and dieback after six months. The pathogen was easily re-isolated from seedlings and re-identified as V. dahliae, thus satisfying Koch’s postulates. Results from intraspecific resistance screening of nine seed sources from across Italy revealed that Ailanthus provenances from all the six sampled regions were susceptible to V. dahliae. Stem inoculated adult plants exhibited abundant production of epicormic sprouts along the stem within six months, and most of these sprouts wilted following initial dieback of the main stem; furthermore, sprouting from the crown was intense. Petioles and rachises tissues of leaves fallen from infected trees were a good source for re-isolation of the pathogen; we proved that such petioles and rachises can effectively transfer the fungus to healthy Ailanthus seedlings via root infections. Host-specificity of the V. dahliae isolate VdGL16 was also determined on 40 non-target species/varieties/cultivars. The isolate caused disease in herbaceous species belonging to five botanical families: Asteraceae, Lamiaceae, Leguminoseae, Linaceae and Solanaceae. Given the difficulties in countering Ailanthus invasion with mechanical and chemical methods, the biological control using Verticillium may provide an efficient, low cost and sustainable control of this invasive species

Normal and cancer-prone human cells respond differently to extremely low frequency magnetic fields. FEBS Lett 487:397–403

Abstract Human lymphoblastoid cells of normal origin and from genetic instability syndromes, i.e. Fanconi anemia (FA) group C and ataxia telangectasia, were continuously exposed to extremely low frequency magnetic field (ELF-MF). We report that ELF-MF, though not perturbing cell cycle progression, increases the rate of cell death in normal cell lines. In contrast, cell death is not affected in cells from genetic instability syndromes; this reflects a specific failure of the apoptotic response. Reintroduction of complementation group C in FA cells re-established the apoptotic response to ELF-MF. Thus, genes implicated in genetic instability syndromes are relevant in modulating the response of cells to ELF-MF.