Development of a process for efficient use of CO2 from flue gases in the production of photosynthetic microorganisms

A new methodology to use efficiently flue gases as CO(2) source in the production of photosynthetic microorganisms is proposed. The CO(2) is absorbed in an aqueous phase that is then regenerated by microalgae. Carbonated solutions could absorb up to 80% of the CO(2) from diluted gas reaching total inorganic carbon (TIC) concentrations up to 2.0 g/L. The pH of the solution was maintained at 8.0-10.0 by the bicarbonate/carbonate buffer, so it is compatible with biological regeneration. The absorption process was modeled and the kinetic parameters were determined. Anabaena sp. demonstrated to tolerate pH (8.0-10.0) and TIC (up to 2.0 g/L) conditions imposed by the absorption step. Experiments of regeneration of the liquid phase demonstrated the feasibility of the overall process, converting CO(2) into organic matter. The developed process avoids heating to regenerate the liquid whereas maximizing the efficiency of CO(2) use, which is relevant to achieve the commercial production of biofuels from microalgae.     

First record of the sea anemone Diadumene lineata (Verrill 1871) associated to Spartina alterniflora roots and stems, in marshes at the Bahia Blanca estuary, Argentina

We report the occurrence of the orange-striped green anemone Diadumene lineata (Verrill 1871) (=Haliplanella lineata) in salt marshes at the Bahía Blanca Estuary for the first time in August 2005. We also found this species attached to roots and stems of Spartina alterniflora, an association that has never been registered before. After their determination, sampling was performed during a year to evaluate seasonal abundance of this sea anemone. Results showed that D. lineata was present through the whole year, indicating the existence of a stable population. All individuals sampled were found attached to roots or stems of S. alterniflora, with the higher abundances detected in summer. Further studies are necessary to precise the potential effects of this exotic sea anemone on salt marsh communities.     

Cytogenetical studies in five Atlantic Anguilliformes fishes

The order Anguilliformes comprises 15 families, 141 genera and 791 fish species. Eight families had at least one karyotyped species, with a prevalence of 2n = 38 chromosomes and high fundamental numbers (FN). The only exception to this pattern is the family Muraenidae, in which the eight species analyzed presented 2n = 42 chromosomes. Despite of the large number of Anguilliformes species, karyotypic reports are available for only a few representatives. In the present work, a species of Ophichthidae, Myrichthys ocellatus (2n = 38; 8m+14sm+10st+6a; FN = 70) and four species of Muraenidae, Enchelycore nigricans (2n = 42; 6m+8sm+12st+16a; FN = 68), Gymnothorax miliaris (2n = 42; 14m+18sm+10st; FN = 84), G. vicinus (2n = 42; 8m+6sm+28a; FN = 56) and Muraena pavonina (2n = 42; 6m+4sm+32a; FN = 52), collected along the Northeastern coast of Brazil and around the St Peter and St Paul Archipelago were analyzed. Typical large metacentric chromosomes were observed in all species. Conspicuous polymorphic heterochromatic regions were observed at the centromeres of most chromosomes and at single ribosomal sites. The data obtained for Ophichthidae corroborate the hypothesis of a karyotypic diversification mainly due to pericentric inversions and Robertsonian rearrangements, while the identification of constant chromosome numbers in Muraenidae (2n = 42) suggests a karyotype diversification through pericentric inversions and heterochromatin processes.     

Clinical and immunological factors associated with lupus nephritis in patients from northwestern Colombia

A cross-sectional and multicenter study was undertaken to analyze the clinical and immunological characteristics at diagnosis associated with nephritis in northwestern Colombian patients with systemic lupus erythematosus (SLE). Thirty-nine patients with lupus nephritis were included and were compared to 100 SLE patients without nephritis. A multivariate analysis was performed. The patients who developed nephritis had a higher frequency of oral ulcers (41% vs. 21%, OR = 3.1, 95% CI: 1.3-7.5 p = 0.01) and malar erythema (77% vs. 45%, OR = 4.4, 95% CI: 1.8-10.8 p = 0.001). Lupus nephritis was observed in 77% of cases during the first year of the disease. The frequency of anti-DNA antibodies was higher in patients with nephritis, however, differences were not statistically significant (83% vs 64%, OR = 2.6, 95% CI: 1.03-6.41, p = 0.06). The presence of other autoantibodies (anti-Ro, anti-La, anti-RNP, anti-Sm and anticardiolipin) at diagnosis was similar in both groups. This autoantibody profile remained unchanged throughout the evolution of the disease. Patients with lupus nephritis had a higher prevalence of arterial hypertension (60% vs 10%, OR = 13.7, 95% IC: 5-37, p = 0.00001) and hyperlipidemia (30% vs 7%, OR = 8.1, 95% IC: 2.5-27, p = 0.0006) at onset. Finally, patients with lupus nephritis required more hospitalizations (> 1) over the course of disease (89% vs 60%, OR = 7.8, 95% CI: 2.1-29, p = 0.002). In conclusion, lupus nephritis appears early during the course of SLE. Malar erythema, oral ulcers, hypertension and hyperlipidemia at onset of disease are associated factors. Lupus nephritis is a major risk factor leading to repeated hospitalizations. This study may help to assist in public health policies in our population in order to improve patient outcomes while simultaneously reducing disease costs.     

Activation of murine lung mast cells by the adenosine A3 receptor

Adenosine has been implicated to play a role in asthma in part through its ability to influence mediator release from mast cells. Most physiological roles of adenosine are mediated through adenosine receptors; however, the mechanisms by which adenosine influences mediator release from lung mast cells are not understood. We established primary murine lung mast cell cultures and used real-time RT-PCR and immunofluorescence to demonstrate that the A(2A), A(2B), and A(3) adenosine receptors are expressed on murine lung mast cells. Studies using selective adenosine receptor agonists and antagonists suggested that activation of A(3) receptors could induce mast cell histamine release in association with increases in intracellular Ca(2+) that were mediated through G(i) and phosphoinositide 3-kinase signaling pathways. The function of A(3) receptors in vivo was tested by exposing mice to the A(3) receptor agonist, IB-MECA. Nebulized IB-MECA directly induced lung mast cell degranulation in wild-type mice while having no effect in A(3) receptor knockout mice. Furthermore, studies using adenosine deaminase knockout mice suggested that elevated endogenous adenosine induced lung mast cell degranulation by engaging A(3) receptors. These results demonstrate that the A(3) adenosine receptor plays an important role in adenosine-mediated murine lung mast cell degranulation.     

Complement component 3 is required for optimal expansion of CD8 T cells during a systemic viral infection

In addition to its established role in innate immune mechanisms, complement component C3 is also of critical importance in B cell activation and T cell-dependent Ab responses. In this study, we have examined the requirement for C3 in the generation of primary CD8 T cell responses to an acute systemic viral infection. We compared Ag-specific CD8 T cell responses to lymphocytic choriomeningitis virus (LCMV) between wild-type (+/+) and C3-deficient (C3(-/-)) mice on both 129/B6 and B6 backgrounds. These studies revealed that C3 activity is required for optimal expansion of LCMV-specific effector CD8 T cells in an epitope-dependent fashion, which is influenced by the genetic background of the mice. Studies in complement receptor 1/2 (CR1/CR2)-deficient mice showed that regulation of LCMV-specific CD8 T cell responses by C3 is not dependent upon CR1/CR2. These findings may have implications in vaccine development, therapy of autoimmune diseases, and prevention of graft rejection.