Urban Influence On Litterfall Trace Metals Fluxes In The Atlantic Forest Of São Paulo (brazil)

A monitoring project for two forest catchments was established in 2001 in São Paulo State, Brazil. The chosen catchments differed significantly with respect to human occupation. One catchment area, PEFI (23°39 minutes S and 46o37 minutes W), is inside the largest metropolis of South America, the city of São Paulo, within a Park of 549.3 ha, located about 50 km away from the ocean. The other catchment area, CUNHA (between parallels 23° 13 minutes 18 seconds and 23° 16 minutes 10 seconds South and meridians 45° 02 minutes 53 seconds and 45° 02 minutes 53 seconds West), is within a State Reserve of the Atlantic Forest, with 2850 ha, located about 15 km from the ocean, surrounded by rural areas and small villages. PEFI is about 798 m above sea level, while CUNHA is about 1050 m. In this work we examined the monthly litterfall trace metal (Fe, Mn, Zn, Cu, Cr, Pb, Cr, Cd, Hg) fluxes for both catchments during the 2001 dry season (may to September). Trace element concentrations were also determined in soils. CUNHA is characterized by low fluxes and low concentrations in soil, compared with PEFI. The same tendency was also observed for rainfall and throughfall Fe, Mn, Zn and Cu fluxes.107I491494Forstner, U., Land contamination by metals: Global scope and magnitude of problems (1995) Metal Speciation and Contamination of Soil, p. 357. , Herbert et alii. Eds. LewisLindberg, S., Forests and the global biogeochemical cycle of mercury: The importance of understanding air/vegetation exchange processes (1996) Global and Regional Mercury Cycles: Sources, Flux and Mass Balances, pp. 359-580. , O. Ed. Kluwer Academic Pub, (1996)Ukonmaanaho, L., Starr, J., Ruoho-Airola, T., (2001) Environmental Pollution, 114, pp. 63-75Bourotte, C., Forti, M.C., Melfi, A.J., Lucas, Y., Caracterização morfológica do material particulado atmosférico em regiões urbana e natural do estado de São Paulo, Brasil VI Congresso de Geoquímica Dos Países de Língua Portuguesa. XII Semana de Geoquímica, Faro, Portugal, 9-12 April 2001, pp. 421-424. , Book of abstractsRodushkin, I., Ruth, T., Huhtasaari, A., (1999) Analytical Chimica Acta, 378, pp. 191-200Forti, C.M., Ciclos biogeoquímicos e transferências de espécies químicas na interface de ecossistemas terrestres de Mata Atlântica: Estudo de duas áreas contratantes (2002), Final report of the FAPESP 99/05204 4 projectMayer, R., Sifgried, L., Lopes, M.I.M.S., Kreutzer, K., (2000) Water, Air and Soil Pollution, 121, pp. 59-78Harada, H., Hatanaka, T., (1998) Soil Science of Plant Nutrition, 44 (3), pp. 443-45

AIP4/Itch Regulates Notch Receptor Degradation in the Absence of Ligand

International audienceBACKGROUND:The regulation of Notch signaling heavily relies on ubiquitination events. Drosophila Su(dx), a member of the HECT family of ubiquitin-ligases, has been described as a negative regulator of Notch signaling, acting on the post-endocytic sorting of Notch. The mammalian ortholog of Su(dx), Itch/AIP4, has been shown to have multiple substrates, including Notch, but the precise events regulated by Itch/AIP4 in the Notch pathway have not been identified yet.METHODOLOGY/PRINCIPAL FINDINGS:Using Itch-/- fibroblasts expressing the Notch1 receptor, we show that Itch is not necessary for Notch activation, but rather for controlling the degradation of Notch in the absence of ligand. Itch is indeed required after the early steps of Notch endocytosis to target it to the lysosomes where it is degraded. Furthermore Itch/AIP4 catalyzes Notch polyubiquitination through unusual K29-linked chains. We also demonstrate that although Notch is associated with Itch/AIP4 in cells, their interaction is not detectable in vitro and thus requires either a post-translational modification, or a bridging factor that remains to be identified.CONCLUSIONS/SIGNIFICANCE:Taken together our results identify a specific step of Notch regulation in the absence of any activation and underline differences between mammalian and Drosophila Notch pathways

Identification of new participants in the rainbow trout (Oncorhynchus mykiss) oocyte maturation and ovulation processes using cDNA microarrays

BACKGROUND: The hormonal control of oocyte maturation and ovulation as well as the molecular mechanisms of nuclear maturation have been thoroughly studied in fish. In contrast, the other molecular events occurring in the ovary during post-vitellogenesis have received far less attention. METHODS: Nylon microarrays displaying 9152 rainbow trout cDNAs were hybridized using RNA samples originating from ovarian tissue collected during late vitellogenesis, post-vitellogenesis and oocyte maturation. Differentially expressed genes were identified using a statistical analysis. A supervised clustering analysis was performed using only differentially expressed genes in order to identify gene clusters exhibiting similar expression profiles. In addition, specific genes were selected and their preovulatory ovarian expression was analyzed using real-time PCR. RESULTS: From the statistical analysis, 310 differentially expressed genes were identified. Among those genes, 90 were up-regulated at the time of oocyte maturation while 220 exhibited an opposite pattern. After clustering analysis, 90 clones belonging to 3 gene clusters exhibiting the most remarkable expression patterns were kept for further analysis. Using real-time PCR analysis, we observed a strong up-regulation of ion and water transport genes such as aquaporin 4 (aqp4) and pendrin (slc26). In addition, a dramatic up-regulation of vasotocin (avt) gene was observed. Furthermore, angiotensin-converting-enzyme 2 (ace2), coagulation factor V (cf5), adam 22, and the chemokine cxcl14 genes exhibited a sharp up-regulation at the time of oocyte maturation. Finally, ovarian aromatase (cyp19a1) exhibited a dramatic down-regulation over the post-vitellogenic period while a down-regulation of Cytidine monophosphate-N-acetylneuraminic acid hydroxylase (cmah) was observed at the time of oocyte maturation. CONCLUSION: We showed the over or under expression of more that 300 genes, most of them being previously unstudied or unknown in the fish preovulatory ovary. Our data confirmed the down-regulation of estrogen synthesis genes during the preovulatory period. In addition, the strong up-regulation of aqp4 and slc26 genes prior to ovulation suggests their participation in the oocyte hydration process occurring at that time. Furthermore, among the most up-regulated clones, several genes such as cxcl14, ace2, adam22, cf5 have pro-inflammatory, vasodilatory, proteolytics and coagulatory functions. The identity and expression patterns of those genes support the theory comparing ovulation to an inflammatory-like reaction

The genome of the seagrass Zostera marina reveals angiosperm adaptation to the sea

Seagrasses colonized the sea(1) on at least three independent occasions to form the basis of one of the most productive and widespread coastal ecosystems on the planet(2). Here we report the genome of Zostera marina (L.), the first, to our knowledge, marine angiosperm to be fully sequenced. This reveals unique insights into the genomic losses and gains involved in achieving the structural and physiological adaptations required for its marine lifestyle, arguably the most severe habitat shift ever accomplished by flowering plants. Key angiosperm innovations that were lost include the entire repertoire of stomatal genes(3), genes involved in the synthesis of terpenoids and ethylene signalling, and genes for ultraviolet protection and phytochromes for far-red sensing. Seagrasses have also regained functions enabling them to adjust to full salinity. Their cell walls contain all of the polysaccharides typical of land plants, but also contain polyanionic, low-methylated pectins and sulfated galactans, a feature shared with the cell walls of all macroalgae(4) and that is important for ion homoeostasis, nutrient uptake and O-2/CO2 exchange through leaf epidermal cells. The Z. marina genome resource will markedly advance a wide range of functional ecological studies from adaptation of marine ecosystems under climate warming(5,6), to unravelling the mechanisms of osmoregulation under high salinities that may further inform our understanding of the evolution of salt tolerance in crop plants(7)

Structural basis of ABCF-mediated resistance to pleuromutilin, lincosamide, and streptogramin A antibiotics in Gram-positive pathogens

he antibiotic target. One class of such proteins are the antibiotic resistance (ARE) ATP-binding cassette (ABC) proteins of the F-subtype (ARE-ABCFs), which are widely distributed throughout Gram-positive bacteria and bind the ribosome to alleviate translational inhibition from antibiotics that target the large ribosomal subunit. Here, we present single-particle cryo-EM structures of ARE-ABCF-ribosome complexes from three Gram-positive pathogens: Enterococcus faecalis LsaA, Staphylococcus haemolyticus VgaALC and Listeria monocytogenes VgaL. Supported by extensive mutagenesis analysis, these structures enable a general model for antibiotic resistance mediated by these ARE-ABCFs to be proposed. In this model, ABCF binding to the antibiotic-stalled ribosome mediates antibiotic release via mechanistically diverse long-range conformational relays that converge on a few conserved ribosomal RNA nucleotides located at the peptidyltransferase center. These insights are important for the future development of antibiotics that overcome such target protection resistance mechanisms

Diagnosis and monitoring of multiple myeloma patients

The diagnosis of multiple myeloma (MM) can be challenging, especially in patients with light-chain or nonsecretory disease. The disease should be excluded in patients presenting with unexplained anaemia or renal failure and suspected in patients with signs of back pain combined with other systemic symptoms, such as fatigue and weight loss, or back pain combined with ab normal blood tests. The diagnosis is based on clinical, biological and radiological abnormalities that are resumed in the current article. At diagnosis, additional cytogenetic testing is important to determine the prognosis and guide physicians in their treatment choices. The disease is generally monitored by quantitying the monoclonal proteins in blood or urine. The follow-up of patients can be further tailored to the patients' general status, obtained response and disease characteristics

Impact of lenalidomide maintenance on the immune environment of multiple myeloma patients with low tumor burden after autologous stem cell transplantation

peer reviewedLenalidomide is a potent anti-myeloma drug with immunomodulatory properties. It is increasingly used in a low-dose maintenance setting to prolong remission duration after standard treatment. Data on the in vivo effects of lenalidomide are scarce and sometimes different from the well-described in vitro effects. We therefore evaluated the numerical, phenotypical and functional impact of lenalidomide maintenance on several immune cell types in a cohort of seventeen homogeneously treated myeloma patients achieving a low residual myeloma burden after a bortezomib based-induction followed by autologous stem cell transplantation. Lenalidomide maintenance: 1) increased the fraction of naïve CD8+ T cells and several memory T-cell subsets, 2) reduced the numbers of terminal effector CD8+ T cells, 3) resulted in a higher expression of co-stimulatory molecules on resting T cells and of the inhibitory checkpoint molecules LAG-3 on CD4+ T cells and TIM-3 on CD4+ and CD8+ T cells, 4) reduced the number of TIGIT+ CD8+ T cells, 5) increased the number of regulatory T cells with a phenotype associated with strong suppressive capacity. Purified CD8+ T cells showed increased and more polyfunctional recall viral responses. However, PBMC responses were not enhanced during lenalidomide maintenance and CD4+ T-cell responses specific for the myeloma-associated antigen MAGE-C1 even tended to become lower. We conclude that lenalidomide maintenance after autologous stem cell transplantation has complex pleotropic effects on the immune environment. Immune interventions such as anti-myeloma vaccination should include measures to tackle an expanded inhibitory Treg compartment. © Fostier et al