585 research outputs found
Increasing the germination percentage of a declining native orchid (Himantoglossum adriaticum) by pollen transfer and outbreeding between populations
The declining native orchid Himantoglossum adriaticum H. Baumann is a European endemic of priority interest (92/43/ EEC, Annex II). Northern Italian populations of H. adriaticum are small and isolated, with depressed seed set. Given the important implications for plant population conservation, we tested the hypothesis that artificial pollen transfer (hand-pollination) and outbreeding between populations increases fruit set and seed germination percentage. The background fruit set and in vitro germination rates were determined for ten reference populations. An artificial cross-pollination experiment included (a) pollen transfer from one large population to two small and isolated populations; (b) pollen transfer between two small but not isolated populations; (c) within-population pollen transfer (control). All seeds were sown on a modified Malmgren's medium and cultured in a controlled environment. Germination percentage was compared using a Kruskal-Wallis anova. The background fruit set (mean = 18%) and germination (<5%) rates were consistently low across populations. Fruit set after hand-pollination was consistently 100%. Pollen transfer from the largest population to smaller populations resulted in an increase in total germination ranging from 0.9% to 2.9%. The largest increase in germination occurred between small-sized and less isolated populations (from 1.7% to 5.1%). The results of pollen transfer between the small populations are particularly encouraging, as the mean increase in germination was almost four times that of the control. Outbreeding can be considered a valuable tool to increase genetic flow and germination in natural populations, limit the accumulation of detrimental effects on fitness driven by repeated breeding with closely-related individuals, thereby increasing the possibility of conservation of rare or endangered species
Expression of calpain-calpastatin system (CCS) member proteins in human lymphocytes of young and elderly individuals; pilot baseline data for the CALPACENT project.
Ubiquitous system of regulatory, calcium-dependent, cytoplasmic proteases – calpains – and their
endogenous inhibitor – calpastatin – is implicated in the proteolytic regulation of activation, proliferation, and
apoptosis of many cell types. However, it has not been thoroughly studied in resting and activated human
lymphocytes yet, especially in relation to the subjects’ ageing process. The CALPACENT project is an international
(Polish-Italian) project aiming at verifying the hypothesis of the role of calpains in the function of peripheral blood
immune cells of Polish (Pomeranian) and Italian (Sicilian) centenarians, apparently relatively preserved in comparison
to the general elderly population. In this preliminary report we aimed at establishing and comparing the baseline
levels of expression of μ- and m-calpain and calpastatin in various, phenotypically defined, populations of human
peripheral blood lymphocytes for healthy elderly Sicilians and Poles, as compared to these values observed in
young cohort
Development and Validation of a 28-gene Hypoxia-related Prognostic Signature for Localized Prostate Cancer.
BACKGROUND: Hypoxia is associated with a poor prognosis in prostate cancer. This work aimed to derive and validate a hypoxia-related mRNA signature for localized prostate cancer.
METHOD: Hypoxia genes were identified in vitro via RNA-sequencing and combined with in vivo gene co-expression analysis to generate a signature. The signature was independently validated in eleven prostate cancer cohorts and a bladder cancer phase III randomized trial of radiotherapy alone or with carbogen and nicotinamide (CON).
RESULTS: A 28-gene signature was derived. Patients with high signature scores had poorer biochemical recurrence free survivals in six of eight independent cohorts of prostatectomy-treated patients (Log rank test P \u3c .05), with borderline significances achieved in the other two (P \u3c .1). The signature also predicted biochemical recurrence in patients receiving post-prostatectomy radiotherapy (n = 130, P = .007) or definitive radiotherapy alone (n = 248, P = .035). Lastly, the signature predicted metastasis events in a pooled cohort (n = 631, P = .002). Prognostic significance remained after adjusting for clinic-pathological factors and commercially available prognostic signatures. The signature predicted benefit from hypoxia-modifying therapy in bladder cancer patients (intervention-by-signature interaction test P = .0026), where carbogen and nicotinamide was associated with improved survival only in hypoxic tumours.
CONCLUSION: A 28-gene hypoxia signature has strong and independent prognostic value for prostate cancer patients
Phenotypic differentiation among native, expansive and introduced populations influences invasion success
Aim: Humans influence species distributions by modifying the environment and by dispersing species beyond their natural ranges. Populations of species that have established in disjunct regions of the world may exhibit trait differentiation from native populations due to founder effects and adaptations to selection pressures in each distributional region. We compared multiple native, expansive and introduced populations of a single species across the world, considering the influence of environmental stressors and transgenerational effects. Location: United States Gulf and Atlantic coasts, United States interior, European Atlantic and Mediterranean coasts, east coast of Australia. Taxon: Baccharis halimifolia L. (eastern baccharis). Methods: We monitored seed germination, seedling emergence, survival and early growth in a common garden experiment, conducted with over 18,200 seeds from 80 populations. We also evaluated the influence of environmental stress and maternal traits on progeny performance. Results: Introduced European Atlantic populations had faster germination and early growth than native populations. However, this was not the case for the more recently naturalized European Mediterranean populations. Introduced Australian populations grew faster than native populations in non-saline environments but had lower survival in saline conditions commonly encountered in the native range. Similarly, expansive inland US populations germinated faster than coastal native populations in non-saline environments but grew and germinated more slowly in saline environments. Maternal inflorescence and plant size were positively related with seed germination and seedling survival, whereas flower abundance was positively correlated with seedling early growth and survival. However, maternal traits explained a much lower fraction of the total variation in early demographic stages of B. halimifolia than did distributional range. Main conclusions: Phenotypic differentiation could allow B. halimifolia to adapt to different biotic and abiotic selection pressures found in each distributional range, potentially contributing to its success in introduced and expansive ranges
Condiciones y medio ambiente de trabajo en hospitales públicos provinciales de la ciudad de Córdoba, Argentina
Esta investigación se propuso caracterizar las condiciones de empleo, identificar riesgos laborales percibidos el trabajador y estimar la frecuencia de problemas de salud referidos por los integrantes de los equipos de salud de hospitales de la ciudad de Córdoba dependientes del Ministerio de Salud de la provincia de Córdoba.
Se realizó un estudio de corte transversal sobre 453 trabajadores pertenecientes a hospitales públicos provinciales de la ciudad de Córdoba, seleccionados mediante muestreo probabilístico aleatorio simple, con un nivel de confianza del 95% y un error muestral del 5%, en quienes se aplicó un cuestionario autoadministrado durante el segundo semestre de 2012.
Se halló que el 35% del personal está vinculado laboralmente mediante formas de contratación no permanentes. El pluriempleo alcanza al 36% de los encuestados. La percepción de riesgos biológicos alcanza el 77,9%, el 50,7% se expone a sustancias químicas y el 51,7% manipula cargas físicas de gran volumen. Los problemas de salud más frecuentemente señalados fueron: gastritis (28,3%), obesidad (24,3%), lumbalgia (19,6%), alteraciones del sueño (14,1%), tensión arterial elevada (12,4%). Las proporciones de trabajadores no estables y de pluriempleo, y la elevada percepción de riesgos en el ámbito laboral deberían motivar la formulación de políticas y normativas de mejora de las condiciones de trabajo y empleo
Correlations among biodiversity, biomass and other plant community parameters using the phytosociological approach: A case study from the south-eastern Alps
The present study deals with the grassland complex of communities which may be found on the limestones in the southeastern
Alps; these communities show in fact a particular interest for their high biodiversity degree and for their importance
for the traditional land-use economy of the south-European mountain regions. Phytosociological releve´s corresponding to
well-defined plant associations have been used in order to get information on the relationships among plant species diversity,
biomass, chorotypes, pollination types, functional strategies and soil characteristics. The analysis was carried out both along
an altitudinal and a soil evolution gradient. The analysis of the correlations among the variables and the application of the
principal component analysis shows a positive correlation between soil parameters and biomass, eurichory, anemogamy and
C- and R-strategies; on the contrary, a negative correlation among stenochory, entomogamy and S-strategy with the soil
evolution seems to be present. This article shows how the phytosociological approach can be used to get information and
knowledge on the correlations between several variables useful to understand the complex nature of the plant communities in
order to support management plans
Molecular excitation in the Interstellar Medium: recent advances in collisional, radiative and chemical processes
We review the different excitation processes in the interstellar mediumComment: Accepted in Chem. Re
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High-Performance Corrosion-Resistant Materials: Iron-Based Amorphous-Metal Thermal-Spray Coatings: SAM HPCRM Program ? FY04 Annual Report ? Rev. 0 - DARPA DSO & DOE OCRWM Co-Sponsored Advanced Materials Program
The multi-institutional High Performance Corrosion Resistant Materials (HPCRM) Team is cosponsored by the Defense Advanced Projects Agency (DARPA) Defense Science Office (DSO) and the Department of Energy (DOE) Office of Civilian Radioactive Waste Management (OCRWM), and has developed new corrosion-resistant, iron-based amorphous metals that can be applied as coatings with advanced thermal spray technology. Two compositions have corrosion resistance superior to wrought nickel-based Alloy C-22 (UNS No. N06022) in very aggressive environments, including concentrated calcium-chloride brines at elevated temperature. Corrosion costs the Department of Defense billions of dollars every year, with an immense quantity of material in various structures undergoing corrosion. For example, in addition to fluid and seawater piping, ballast tanks, and propulsions systems, approximately 345 million square feet of structure aboard naval ships and crafts require costly corrosion control measures. The use of advanced corrosion-resistant materials to prevent the continuous degradation of this massive surface area would be extremely beneficial. The Fe-based corrosion-resistant, amorphous-metal coatings under development may prove of importance for applications on ships. Such coatings could be used as an 'integral drip shield' on spent fuel containers, as well as protective coatings that could be applied over welds, thereby preventing exposure to environments that might cause stress corrosion cracking. In the future, such new high-performance iron-based materials could be substituted for more-expensive nickel-based alloys, thereby enabling a reduction in the $58-billion life cycle cost for the long-term storage of the Nation's spent nuclear fuel by tens of percent
The small-nucleolar RNAs commonly used for microRNA normalisation correlate with tumour pathology and prognosis
Background:To investigate small-nucleolar RNAs (snoRNAs) as reference genes when measuring miRNA expression in tumour samples, given emerging evidence for their role in cancer.Methods:Four snoRNAs, commonly used for normalisation, RNU44, RNU48, RNU43 and RNU6B, and miRNA known to be associated with pathological factors, were measured by real-time polymerase chain reaction in two patient series: 219 breast cancer and 46 head and neck squamous cell carcinoma (HNSCC). SnoRNA and miRNA were then correlated with clinicopathological features and prognosis.Results:Small-nucleolar RNA expression was as variable as miRNA expression (miR-21, miR-210, miR-10b). Normalising miRNA PCR expression data to these recommended snoRNAs introduced bias in associations between miRNA and pathology or outcome. Low snoRNA expression correlated with markers of aggressive pathology. Low levels of RNU44 were associated with a poor prognosis. RNU44 is an intronic gene in a cluster of highly conserved snoRNAs in the growth arrest specific 5 (GAS5) transcript, which is normally upregulated to arrest cell growth under stress. Low-tumour GAS5 expression was associated with a poor prognosis. RNU48 and RNU43 were also identified as intronic snoRNAs within genes that are dysregulated in cancer.Conclusion:Small-nucleolar RNAs are important in cancer prognosis, and their use as reference genes can introduce bias when determining miRNA expression. © 2011 Cancer Research UK All rights reserved
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