Environmental analysis of rainwater harvesting infrastructures in diffuse and compact urban models of Mediterranean climate

Purpose  

At present, many urban areas in Mediterranean climates are coping with water scarcity, facing a growing water demand and a limited conventional water supply. Urban design and planning has so far largely neglected the benefits of rainwater harvesting (RWH) in the context of a sustainable management of this resource. Therefore, the purpose of this study was to identify the most environmentally friendly strategy for rainwater utilization in Mediterranean urban environments of different densities.     

Nuclear accumulation of fructose 1,6-bisphosphatase is impaired in diabetic rat liver

Using a streptozotocin-induced type 1 diabetic rat model, we analyzed and separated the effects of hyperglycemia and hyperinsulinemia over the in vivo expression and subcellular localization of hepatic fructose 1,6-bisphosphatase (FBPase) in the multicellular context of the liver. Our data showed that FBPase subcellular localization was modulated by the nutritional state in normal but not in diabetic rats. By contrast, the liver zonation was not affected in any condition. In healthy starved rats, FBPase was localized in the cytoplasm of hepatocytes, whereas in healthy re-fed rats it was concentrated in the nucleus and the cell periphery. Interestingly, despite the hyperglycemia, FBPase was unable to accumulate in the nucleus in hepatocytes from streptozotocin-induced diabetic rats, suggesting that insulin is a critical in vivo modulator. This idea was confirmed by exogenous insulin supplementation to diabetic rats, where insulin was able to induce the rapid accumulation of FBPase within the hepatocyte nucleus. Besides, hepatic FBPase was found phosphorylated only in the cytoplasm, suggesting that the phosphorylation state is involved in the nuclear translocation. In conclusion, insulin and not hyperglycemia plays a crucial role in the nuclear accumulation of FBPase in vivo and may be an important regulatory mechanism that could account for the increased endogenous glucose production of liver of diabetic rodents.     

Field testing, gene flow assessment and pre-commercial studies on transgenic Solanum tuberosum spp. tuberosum (cv. Spunta) selected for PVY resistance in Argentina

Solanum tuberosum ssp. tuberosum (cv. Spunta) was transformed with a chimeric transgene containing the Potato virus Y (PVY) coat protein (CP) sequence. Screening for PVY resistance under greenhouse conditions yielded over 100 independent candidate lines. Successive field testing of selected lines allowed the identification of two genetically stable PVY-resistant lines, SY230 and SY233, which were further evaluated in field trials at different potato-producing regions in Argentina. In total, more than 2,000 individuals from each line were tested along a 6-year period. While no or negligible PVY infection was observed in the transgenic lines, infection rates of control plants were consistently high and reached levels of up to 70-80%. Parallel field studies were performed in virus-free environments to assess the agronomical performance of the selected lines. Tubers collected from these assays exhibited agronomical traits and biochemical compositions indistinguishable from those of the non-transformed Spunta cultivar. In addition, an interspecific out-crossing trial to determine the magnitude of possible natural gene flow between transgenic line SY233 and its wild relative Solanum chacoense was performed. This trial yielded negative results, suggesting an extremely low probability for such an event to occur.     

The proliferative response of NB69 human neuroblastoma cells to a 50 Hz magnetic field is mediated by ERK1/2 signaling

A number of studies have reported that extremely low frequency magnetic fields (ELF-MF) can modulate proliferative processes in vitro; however, the transduction mechanisms implicated in such phenomena remain to be identified. The present study was aimed to determine whether a 50 Hz, 100 μT MF can induce cell proliferation in the human neuroblastoma line NB69, and whether the signaling pathway MAPK-ERK1/2 (Mitogen-Activated Protein Kinase - Extracellular-Signal-Regulated Kinase 1 and 2) is involved in that proliferative response. The cultures were exposed intermittently or continuously to the MF for a 63-hour duration. The continuous treatment did not induce significant changes in cell proliferation. In contrast, intermittent exposure caused statistically significant increase in the percent of cells in phase S of the cell cycle, followed by a significant increase in cell number. The intermittent treatment also induced an early, transient and repetitive activation of ERK1/2 that could be involved in the proliferative effects. In fact, both the proliferative response and the repeated activation of ERK1/2 were blocked by PD98059, the specific inhibitor of MEK (ERK kinases 1 and 2). Taken together, the described results indicate that a 50 Hz, 100 μT MF can stimulate proliferation in NB69 cells by triggering MAPK-ERK1/ 2 signaling at each of the "On" periods of an intermittent exposure.     

Biochemical characterization of recombinant L-asparaginase (AnsA) from Rhizobium etli, a member of an increasing rhizobial-type family of L-asparaginases

We report the expression, purification, and characterization of L-asparaginase (AnsA) from Rhizobium etli. The enzyme was purified to homogeneity in a single-step procedure involving affinity chromatography, and the kinetic parameters K(m), V(max), and k(cat) for L-asparagine were determined. The enzymatic activity in the presence of a number of substrates and metal ions was investigated. The molecular mass of the enzyme was 47 kDa by SDS-PAGE. The enzyme showed a maximal activity at 50 degrees C, but the optimal temperature of activity was 37 degrees C. It also showed maximal and optimal activities at pH 9.0. The values of K(m), V(max), k(cat), and k(cat)/K(m) were 8.9 +/- 0.967 × 10?3 M, 128 +/- 2.8 U/mg protein, 106 +/- 2 s?1, and 1.2 +/- 0.105 × 10? M?1s?1, respectively. The L-asparaginase activity was reduced in the presence of Mn2?, Zn2?, Ca2?, and Mg2? metal ions for about 52% to 31%. In addition, we found that NH??, L-Asp, D-Asn, and beta-aspartyl-hydroxamate in the reaction buffer reduced the activity of the enzyme, whereas L-Gln did not modify its enzymatic activity. This is the first report on the expression and characterization of the L-asparaginase (AnsA) from R. etli. Phylogenetic analysis of asparaginases reveals an increasing group of known sequences of the Rhizobialtype asparaginase II family.     

Electrospray ionization mass spectrometry analysis of polyisoprenoid alcohols via Li+ cationization

Direct analysis of polyisoprenoids by electrospray ionization mass spectrometry (ESI-MS) often produces poor results requiring off-line time and sample-consuming derivatization techniques. We describe a simple ESI-MS approach for the direct analysis of polyisoprenoids using several dolichols and polyprenols with different chain sizes as proof-of-principle cases. Lithium iodide is used to promote cationization by intense formation of [M+Li]+ adducts. Thus, detection of polyisoprenoids with mass determination can be performed with high sensitivity (limit of detection [LOD] approximately 100 rhoM), whereas characteristic collision-induced dissociations observed for both dolichols and polyprenols permit investigation of their structure. Using ESI(Li+)-MS and ESI(Li+)-MS/MS analysis, we screened for polyprenol products of an octaprenyl pyrophosphate synthase of Plasmodium falciparum and dolichols in a complex mixture of compounds produced by Leishmania amazonensis and P. falciparum.     

Cutting edge: Decreased accumulation and regulatory function of CD4+ CD25(high) T cells in human STAT5b deficiency

We show that STAT5b is important for the in vivo accumulation of CD4+ CD25(high) T cells with regulatory cell function. A patient homozygous for a missense A630P STAT5b mutation displayed immune dysregulation and decreased numbers of CD4+ CD25(high) T cells. STAT5b(A630P/A630P) CD4+ CD25(high) T cells had low expression of forkhead box P3 and an impaired ability to suppress the proliferation of or to kill CD4+ CD25- T cells. Expression of CD25, a component of the high-affinity IL-2R, was also reduced in response to IL-2 or after in vitro propagation. The impact of the STAT5b mutation was selective in that IL-2-mediated up-regulation of the common gamma-chain cytokine receptor and perforin, and activation-induced expressions of CD154 and IFN-gamma were normal. These results indicate that STAT5b propagates an important IL-2-mediated signal for the in vivo accumulation of functional regulatory T cells.     

IL-27 limits IL-2 production during Th1 differentiation

Although the ability of IL-27 to promote T cell responses is well documented, the anti-inflammatory properties of this cytokine remain poorly understood. The current work demonstrates that during infection with Toxoplasma gondii, IL-27R-deficient mice generate aberrant IL-2 responses that are associated with the development of a lethal inflammatory disease. Because in vivo depletion of IL-2 prolongs the survival of infected IL-27R-/- mice, these data suggest that IL-27 curbs the development of immunopathology by limiting parasite-induced IL-2 production. Consistent with this hypothesis, IL-27R-/- CD4+ T cells produce more IL-2 than wild-type counterparts during in vitro differentiation, and when rIL-27 is introduced, it can suppress the expression of IL-2 mRNA and protein by the latter group. Additionally, these studies reveal that, like IL-27, IL-12 can inhibit IL-2 production, and although each employs distinct mechanisms, they can synergize to enhance the effect. In contrast, this property is not shared by closely related cytokines IL-6 and IL-23. Thus, while traditionally viewed as proinflammatory agents, the present findings establish that IL-27 and IL-12 cooperate to limit the availability of IL-2, a potent T cell growth and survival factor. Moreover, because the current studies demonstrate that both can induce expression of suppressor of cytokine signaling 3, a protein that tempers cytokine receptor signaling, they also suggest that IL-27 and IL-12 share additionally inhibitory properties.