Future hotspots of terrestrial mammal loss

Current levels of endangerment and historical trends of species and habitats are the main criteria used to direct conservation efforts globally. Estimates of future declines, which might indicate different priorities than past declines, have been limited by the lack of appropriate data and models. Given that much of conservation is about anticipating and responding to future threats, our inability to look forward at a global scale has been a major constraint on effective action. Here, we assess the geography and extent of projected future changes in suitable habitat for terrestrial mammals within their present ranges. We used a global earth-system model, IMAGE, coupled with fine-scale habitat suitability models and parametrized according to four global scenarios of human development. We identified the most affected countries by 2050 for each scenario, assuming that no additional conservation actions other than those described in the scenarios take place. We found that, with some exceptions, most of the countries with the largest predicted losses of suitable habitat for mammals are in Africa and the Americas. African and North American countries were also predicted to host the most species with large proportional global declines. Most of the countries we identified as future hotspots of terrestrial mammal loss have little or no overlap with the present global conservation priorities, thus confirming the need for forward-looking analyses in conservation priority setting. The expected growth in human populations and consumption in hotspots of future mammal loss mean that local conservation actions such as protected areas might not be sufficient to mitigate losses. Other policies, directed towards the root causes of biodiversity loss, are required, both in Africa and other parts of the world.     

Risk Factors for Death from Influenza A(H1N1)pdm09, State of S?o Paulo,Brazil, 2009

This case-control study aimed to assess the risk factors for death from influenza A(H1N1)pdm09 in patients with laboratory confirmation, who had severe acute respiratory illness-SARI and were hospitalized between June 28^th and August 29^th 2009, in the metropolitan regions of São Paulo and Campinas, Brazil. Medical charts of all the 193 patients who died (cases) and the 386 randomly selected patients who recovered (controls) were investigated in 177 hospitals. Household interviews were conducted with those who had survived and the closest relative of those who had died. 73.6% of cases and 38.1% of controls were at risk of developing influenza-related complications. The 18-to-59-year age group (OR = 2.31, 95%CI: 1.31–4.10 (reference up to 18 years of age)), presence of risk conditions for severity of influenza (OR = 1.99, 95%CI: 1.11–3.57, if one or OR = 6.05, 95%CI: 2.76–13.28, if more than one), obesity (OR = 2.73, 95%CI: 1.28–5.83), immunosuppression (OR = 3.43, 95%CI: 1.28–9.19), and search for previous care associated with the hospitalization (OR = 3.35, 95%CI: 1.75–6.40) were risk factors for death. Antiviral treatment performed within 72 hours of the onset of symptoms (OR = 0.17, 95%CI: 0.08–0.37, if within 48hours, and OR = 0.30, 95%CI: 0.11–0.81, if between 48 and 72 hours) was protective against death. The identification of high-risk patients and early treatment are important factors for reducing morbi-mortality from influenza.     

Structural Insights on Two Hypothetical Secretion Chaperones from <Emphasis Type="Italic">Xanthomonas axonopodis</Emphasis> pv<Emphasis Type="Italic">. citri</Emphasis>

Several Gram-negative bacterial pathogens have developed type III secretion systems (T3SSs) to deliver virulence proteins directly into eukaryotic cells in a process essential for many diseases. The type III secretion processes require customized chaperones with high specificity for binding partners, thus providing the secretion to occur. Due to the very low sequence similarities among secretion chaperones, annotation and discrimination of a great majority of them is extremely difficult and a task with low scores even if genes are encountered that codify for small (<20 kDa) proteins with low pI and a tendency to dimerise. Concerning about this, herein, we present structural features on two hypothetical T3SSs chaperones belonging to plant pathogen Xanthomonas axonopodis pv. citri and suggest how low resolution models based on Small Angle X-ray Scattering patterns can provide new structural insights that could be very helpful in their analysis and posterior classification.     

Drug-induced expansion and differentiation of V gamma 9V delta 2 T cells in vivo: the role of exogenous IL-2

Human Vgamma9Vdelta2 T cells recognize nonpeptidic Ags generated by the 1-deoxy-d-xylulose 5-phosphate (many eubacteria, algae, plants, and Apicomplexa) and mevalonate (eukaryotes, archaebacteria, and certain eubacteria) pathways of isoprenoid synthesis. The potent Vgamma9Vdelta2 T cell reactivity 1) against certain cancer cells or 2) induced by infectious agents indicates that therapeutic augmentations of Vgamma9Vdelta2 T cell activities may be clinically beneficial. The functional characteristics of Vgamma9Vdelta2 T cells from Macaca fascicularis (cynomolgus monkey) are very similar to those from Homo sapiens. We have found that the i.v. administration of nitrogen-containing bisphosphonate or pyrophosphomonoester drugs into cynomolgus monkeys combined with s.c. low-dose (6 x 10(5) U/animal) IL-2 induces a large pool of CD27+ and CD27- effector/memory T cells in the peripheral blood of treated animals. The administration of these drugs in the absence of IL-2 is substantially less effective, indicating the importance of additional exogenous costimuli. Shortly after the costimulatory IL-2 treatment, only gammadelta (but not alphabeta) T cells expressed the CD69 activation marker, indicating that Vgamma9Vdelta2 T lymphocytes are more responsive to low-dose IL-2 than alphabeta T cells. Up to 100-fold increases in the numbers of peripheral blood Vgamma9Vdelta2 T cells were observed in animals receiving the gammadelta stimulatory drug plus IL-2. Moreover, the expanded Vgamma9Vdelta2 T cells were potent Th1 effectors capable of releasing large amounts of IFN-gamma. These results may be relevant for designing novel (or modifying current) immunotherapeutic trials with nitrogen-containing bisphosphonate or pyrophosphomonoester drugs.     

Selection of thrombin-binding aptamers by using computational approach for aptasensor application

The possibility of introducing a computationally assisted method to study aptamer-protein interaction was evaluated with the aim of streamlining the screening and selection of new aptamers. Starting from information on the 15-mer (5'-GGTTGGTGTGGTTGG-3') thrombin binding aptamer (TBA), a library of mutated DNA sequences (994 elements) was generated and screened using shapegauss a shape-based scoring function from openeye software to generate computationally derived binding scores. The TBA and three other mutated oligonucleotides, selected on the basis of their binding score (best, medium, worst), were incorporated into surface plasmon resonance (SPR) biosensors. By reducing the ionic strength (binding buffer, 50 mM TrisHCl pH 7.4, 140 mM NaCl, 1mM MgCl?, diluted 1:50) in order to match the simulated condition, the analytical performances of the four oligonucleotide sequences were compared using signal amplitude, sensitivity (slope), linearity (R2) and reproducibility (CVav %). The experimental results were in agreement with the simulation findings.     

IRF4-Dependent and IRF4-Independent Pathways Contribute to DC Dysfunction in Lupus

Interferon Regulatory Factors (IRFs) play fundamental roles in dendritic cell (DC) differentiation and function. In particular, IRFs are critical transducers of TLR signaling and dysregulation in this family of factors is associated with the development of autoimmune disorders such as Systemic Lupus Erythematosus (SLE). While several IRFs are expressed in DCs their relative contribution to the aberrant phenotypic and functional characteristics that DCs acquire in autoimmune disease has not been fully delineated. Mice deficient in both DEF6 and SWAP-70 (= Double-knock-out or DKO mice), two members of a unique family of molecules that restrain IRF4 function, spontaneously develop a lupus-like disease. Although autoimmunity in DKO mice is accompanied by dysregulated IRF4 activity in both T and B cells, SWAP-70 is also known to regulate multiple aspects of DC biology leading us to directly evaluate DC development and function in these mice. By monitoring Blimp1 expression and IL-10 competency in DKO mice we demonstrate that DCs in these mice exhibit dysregulated IL-10 production, which is accompanied by aberrant Blimp1 expression in the spleen but not in the peripheral lymph nodes. We furthermore show that DCs from these mice are hyper-responsive to multiple TLR ligands and that IRF4 plays a differential role in in these responses by being required for the TLR4-mediated but not the TLR9-mediated upregulation of IL-10 expression. Thus, DC dysfunction in lupus-prone mice relies on both IRF4-dependent and IRF4-independent pathways.     

A xylan-degrading strain of<Emphasis Type="Italic"> Sulfolobus solfataricus</Emphasis>: isolation and characterization of the xylanase activity

Two strains (O and X₂) of the hyperthermophilic crenarchaeon Sulfolobus solfataricus strain MT4 were selected and isolated for their ability to grow on xylan. O and X₂, grown on media containing oat spelt xylan and birchwood xylan as the sole nutrient source, respectively, produced the same thermostable xylanase that was demonstrated to be inducible in xylan cultures. In an oat spelt medium, S. solfataricus O underwent interesting morphological changes in the cell envelope, exhibiting mobile appendages not present in the typical coccal shape. The enzyme was prevalently membrane associated and showed a molecular mass of approximately 57.0 kDa. It was also highly thermostable, with a half-life of 47 min at 100°C, and exhibited an optimal temperature and pH of 90°C and 7.0, respectively. Xylo-oligosaccharides were the enzymatic products of xylan hydrolysis, and the smallest degradation product was xylobiose, thus indicating that the enzyme was an endoxylanase. The enzyme was able to bind weakly to crystalline cellulose (Avicel) and more strongly to insoluble xylan in a substrate amount-and temperature-dependent manner.Communicated by G. Antranikian     

Site-Specific Integration in Mammalian Cells Mediated by a New Hybrid Baculovirus–Adeno-Associated Virus Vector

Baculovirus can transiently transduce primary human and rat hepatocytes, as well as a subset of stable cell lines. To prolong transgene expression, we have developed new hybrid vectors which associate key elements from adeno-associated virus (AAV) with the elevated transducing capacity of baculovirus. The hybrid vectors contain a transgene cassette composed of the β-galactosidase (β-Gal) reporter gene and the hygromycin resistance (Hyg^r) gene flanked by the AAV inverted terminal repeats (ITRs), which are necessary for AAV replication and integration in the host genome. Constructs were derived both with and without the AAV rep gene under the p5 and p19 promoters cloned in different positions with respect to the baculovirus polyheidrin promoter. A high-titer preparation of baculovirus-AAV (Bac-AAV) chimeric virus containing the ITR–Hyg^r–β-Gal sequence was obtained with insect cells only when the rep gene was placed in an antisense orientation to the polyheidrin promoter. Infection of 293 cells with Bac-AAV virus expressing the rep gene results in a 10- to 50-fold increase in the number of Hyg^r stable cell clones. Additionally, rep expression determined the localization of the transgene cassette in the aavs1 site in approximately 41% of cases as detected by both Southern blotting and fluorescent in situ hybridization analysis. Moreover, site-specific integration of the ITR-flanked DNA was also detected by PCR amplification of the ITR-aavs1 junction in transduced human fibroblasts. These data indicate that Bac-AAV hybrid vectors can allow permanent, nontoxic gene delivery of DNA constructs for ex vivo treatment of primary human cells.