Las orquídeas de la Reserva de la Biosfera Torres del Paine: La necesidad de implementar monitoreo de especies y planificación ecoturística para la conservación de la biodiversidad

The orchid flora of Torres del Paine Biosphere Reserve (TPBR) is described based on botanical surveys, photographicalrecords and herbarium collections carried out by the authors. This list comprises 3 genera and 9 species: Chloraea chica,Chloraea leptopetala, Chloraea magellanica, Codonorchis lessonii, Gavilea araucana, Gavilea gladysiae, Gavilealittoralis, Gavilea lutea and Gavilea supralabellata. G. gladysiae is a new record for this protected area and the firstalbino aberrant phenotype for flowers of Chl. magellanica is reported. A description of the species including key fordetermination, morphology, habitats, local abundances, flowering phenology and photographs is provided. The speciesrichness here reported represents ca. 35% of orchids occurring in the Chilean temperate-austral floristic regions and 75%of the species described for the Magallanes Region, putting the Torres del Paine Biosphere Reserve as one of the mostrepresentative protected areas for this taxonomical group in the region. Based on our results we addressed the need ofestablishing monitoring programs for orchids and promote them as flagship species in ecotourism planning in order toenhance species valuation and encourage biodiversity conservation.  Se describen las orquídeas de la Reserva de la Biosfera Torres del Paine sobre la base de exploraciones botánicas, registrosfotográficos y colecciones de herbario llevadas a cabo por los autores. Esta lista comprende 3 géneros y 9 especies: Chloraeachica, Chloraea leptopetala, Chloraea magellanica, Codonorchis lessonii, Gavilea araucana, Gavilea gladysiae, Gavilealittoralis, Gavilea lutea y Gavilea supralabellata. G. gladysiae es un registro nuevo para esta área protegida y se reporta elprimer fenotipo aberrante de flores albinas de Chl. magellanica. Se provee de una descripción de las especies que incluyemorfología, habitats, abundancias locales, fenología de floración y fotografías. La riqueza de especies aquí reportadarepresenta cerca del 35% de las orquídeas que se distribuyen en las regiones florísticas Templada-Austral y el 75% de lasespecies descritas para la Región de Magallanes, colocando a la Reserva de la Biosfera Torres del Paine como una de lasáreas protegidas más representativas para este grupo taxonómico en Chile. Basados en nuestros resultados recalcamosla necesidad de establecer programas de monitoreo para las orquídeas y promoverlas como especies emblemáticas enplanificación ecoturística para así incrementar la valoración de las especies y reforzar la conservación de la biodiversidad

Heterogeneous aging in spin glasses

We introduce a set of theoretical ideas that form the basis for an analytical framework capable of describing nonequilibrium dynamics in glassy systems. We test the resulting scenario by comparing its predictions with numerical simulations of short-range spin glasses. Local fluctuations and responses are shown to be connected by a generalized local out-of-equilibrium fluctuation-dissipation relation. Scaling relationships are uncovered for the slow evolution of heterogeneities at all time scales.Comment: Substantially reorganized to improve clarity of exposition. Accepted for publication in Physical Review Letters. 5 pages, 4 figure

Cohort Profile: The Study of Respiratory Pathogens in Andean Children

We investigated respiratory pathogens in a prospective cohort study of young children living in the Peruvian Andes. In the study we assessed viral respiratory infections among young children, and explored interactions of viruses with common respiratory bacteria, especially Streptococcus pneumoniae. Through weekly household visits, data were collected on the signs and symptoms of acute respiratory illness (ARI), nasal samples were collected to test for viruses during episodes of ARI, and nasopharyngeal samples were collected on a monthly basis to monitor bacterial colonisation. We also collected data on vaccination coverage, patterns of social mixing, geographic information, and environmental and socio-demographic variables. Understanding the interaction of respiratory viruses with bacteria and its impact on the burden and severity of ARIs in rural areas of developing countries is critical to designing strategies for preventing such infections. Investigators interested in more details about this study or in accessing these resources should contact Dr. Carlos G. Grijalva at Vanderbilt University ([email protected]

Nasopharyngeal pneumococcal density is associated with viral activity but not with use of improved stoves among young Andean children

Indoor smoke exposure is common in developing countries and may influence nasopharyngeal (NP) pneumococcal colonization density and risk of acute respiratory illness. We compared colonization density among Andean children living in households previously enrolled in a randomized controlled trial of a home intervention package including improved stoves to reduce smoke, kitchen sinks, and water disinfection.; We enrolled 260 children aged <3 years and made weekly household visits to assess for acute respiratory illness (ARI) and collect nasal swabs for respiratory virus polymerase chain reaction (PCR) testing during ARI. At monthly intervals, NP swabs were collected to determine pneumococcal colonization density through quantitative lytA PCR. We used linear quantile mixed-effects models to compare median log-transformed colonization densities among children in households randomized to the control (n = 129) versus intervention (n = 131) in sequential time points, accounting for random effects of multiple="multiple" samples from individual children. Other covariates included age, sex, month, antibiotic exposure, and timing of sample collection relative to ARI with and without viral detection.; Age and sociodemographic characteristics were similar between groups. Although no differences were observed in densities between groups, colonization density varied significantly over time in both groups, with highest densities coinciding with spring months. Time during and after virus-associated ARI was also associated with higher pneumococcal colonization density than time remote from ARIs.; A home intervention package, including improved stoves, was not associated with changes in pneumococcal densities in young Andean children. However, increasing pneumococcal density was observed with spring season and viral-associated ARIs

BK virus associated meningoencephalitis in an AIDS patient treated with HAART

A severely immune-suppressed AIDS patient was suspected of suffering from BK virus (BKV) meningoencephalitis, after being studied for common causes of neurological complications of co-infectious origin. Polymerase chain reaction (PCR) and sequence analysis of cerebrospinal fluid and brain samples, confirmed the presence of BKV. His clinical condition improved along with the regression of brain lesions, after modifications on his antiretroviral regime. Five months after discharge, the patient was readmitted because of frequent headaches, and a marked inflammatory reaction was evidenced by a new magnetic resonance imaging (MRI). The symptoms paralleled a rising CD4+ lymphocyte count, and immune reconstitution syndrome was suspected. This is the first non-postmortem report of BKV meningoencephalitis in an AIDS patient, showing clinical and radiographic improvement solely under HAART

Periodic orbits and non-integrability in a cosmological scalar field

Agraïments: The second author is partially supported by Fondecyt 1080112.We apply the averaging theory of first order to study the periodic orbits of Hamiltonian systems describing an universe filled with a scalar field which possesses three parameters. The main results are the following. First, we provide sufficient conditions on the parameters of these cosmological model, which guarantee that at any positive or negative Hamiltonian level, the Hamiltonian system has periodic orbits, the number of such periodic orbits and their stability change with the values of the parameters. These periodic orbits live in the whole phase space in a continuous family of periodic orbits parameterized by the Hamiltonian level. Second, under convenient assumptions we show the non-integrability of these cosmological systems in the sense of Liouville-Arnol'd, proving that cannot exist any second first integral of class C1. It is important to mention that the tools (i.e the averaging theory for studying the existence of periodic orbits and their kind of stability, and the multipliers of these periodic orbits for studying the integrability of the Hamiltonian system) used here for proving our results on the cosmological scalar field, can be applied to Hamiltonian systems with an arbitrary number of degrees of freedom

Molecular and phylogenetic analysis of HIV-1 variants circulating in Italy

<p>Abstract</p> <p>Objective</p> <p>The continuous identification of HIV-1 non-B subtypes and recombinant forms in Italy indicates the need of constant molecular epidemiology survey of genetic forms circulating and transmitted in the resident population.</p> <p>Methods</p> <p>The distribution of HIV-1 subtypes has been evaluated in 25 seropositive individuals residing in Italy, most of whom were infected through a sexual route during the 1995–2005 period. Each sample has been characterized by detailed molecular and phylogenetic analyses.</p> <p>Results</p> <p>18 of the 25 samples were positive at HIV-1 PCR amplification. Three samples showed a nucleotide divergence compatible with a non-B subtype classification. The phylogenetic analysis, performed on both HIV-1 <it>env </it>and <it>gag </it>regions, confirms the molecular sub-typing prediction, given that 1 sample falls into the C subtype and 2 into the G subtype. The B subtype isolates show high levels of <it>intra</it>-subtype nucleotide divergence, compatible with a long-lasting epidemic and a progressive HIV-1 molecular diversification.</p> <p>Conclusion</p> <p>The Italian HIV-1 epidemic is still mostly attributable to the B subtype, regardless the transmission route, which shows an increasing nucleotide heterogeneity. Heterosexual transmission and the interracial blending, however, are slowly introducing novel HIV-1 subtypes. Therefore, a molecular monitoring is needed to follow the constant evolution of the HIV-1 epidemic.</p

Prion Protein Misfolding Affects Calcium Homeostasis and Sensitizes Cells to Endoplasmic Reticulum Stress

Prion-related disorders (PrDs) are fatal neurodegenerative disorders characterized by progressive neuronal impairment as well as the accumulation of an abnormally folded and protease resistant form of the cellular prion protein, termed PrPRES. Altered endoplasmic reticulum (ER) homeostasis is associated with the occurrence of neurodegeneration in sporadic, infectious and familial forms of PrDs. The ER operates as a major intracellular calcium store, playing a crucial role in pathological events related to neuronal dysfunction and death. Here we investigated the possible impact of PrP misfolding on ER calcium homeostasis in infectious and familial models of PrDs. Neuro2A cells chronically infected with scrapie prions showed decreased ER-calcium content that correlated with a stronger upregulation of UPR-inducible chaperones, and a higher sensitivity to ER stress-induced cell death. Overexpression of the calcium pump SERCA stimulated calcium release and increased the neurotoxicity observed after exposure of cells to brain-derived infectious PrPRES. Furthermore, expression of PrP mutants that cause hereditary Creutzfeldt-Jakob disease or fatal familial insomnia led to accumulation of PrPRES and their partial retention at the ER, associated with a drastic decrease of ER calcium content and higher susceptibility to ER stress. Finally, similar results were observed when a transmembrane form of PrP was expressed, which is proposed as a neurotoxic intermediate. Our results suggest that alterations in calcium homeostasis and increased susceptibility to ER stress are common pathological features of both infectious and familial PrD models