Primary Production and Nutrient Content in Two Salt Marsh

Seasonal variation patterns of aboveground and belowground biomass, net primary production, and nutrient accumulation were assessed in Atriplex portulacoides L. and Limoniastrum monopetalum (L.) Boiss. in Castro Marim salt marsh, Portugal. Sampling was conducted for five periods during 2001–2002 (autumn, winter, spring, summer, and autumn). This study indicates that both species have a clear seasonal variation pattern for both aboveground and belowground biomass. Mean live biomass was 2516 g m22 yr21 for L. monopetalum and 598 g m22 yr21 for A. portulacoides. Peak living biomass, in spring for both species, was three times greater in the former, 3502 g m22 yr21, than in the latter, 1077 g m22 yr21. For both the Smalley (Groenendijk 1984) and Weigert and Evans (1964) methods, productivity of L. monopetalum (2917 and 3635 g m22 yr21, respectively) was greater than that of A. portulacoides (1002 and 1615 g m22 yr21, respectively). Belowground biomass of L. monopetalum was 1.7 times greater than that of A. portulacoides. In spite of this, the root:shoot ratio for A. portulacoides was greater throughout the year. This shows that A. portulacoides allocates more biomass to roots and L. monopetalum to aerial components. Leaf area index was similar for both species, but specific leaf area of A. portulacoides was twice that of L. monopetalum. The greatest nutrient contents were found in leaves. Leaf nitrogen content was maximum in summer for both species (14.6 mg g21 for A. portulacoides and 15.5 mg g21 for L. monopetalum). Leaf phosphorus concentration was minimum in summer (1.1 mg g21 in A. portulacoides and 1.2 mg g21 in L. monopetalum). Leaf potassium contents in A. portulacoides were around three times greater than in L. monopetalum. Leaf calcium contents in L. monopetalum were three times greater than in A. portulacoides. There was a pronounced seasonal variation of calcium content in the former, while in the latter no clear variation was registered. Both species exhibited a decrease in magnesium leaf contents in the summer period. Manganese content in L. monopetalum leaves was tenfold that in A. portulacoides. Seasonal patterns of nutrient contents in A. portulacoides and L. monopetalum suggest that availability of these elements was not a limiting factor to biomass production

Antinociceptive properties and acute toxicity of ethanol extract of Bromelia laciniosa Mart. ex Schult. f. (Bromeliaceae)

Purpose: To investigate the antinociceptive activity and acute toxicity of the ethanol extract of Bromelia laciniosa leaf.Methods: A high performance liquid chromatography HPLC fingerprint of phenolic compounds was developed. The antinociceptive effect of ethanol extract (Bl-EtOH) in mice was carried out using chemical (writhing and formalin) and thermal (hot plate) models of nociception. The acute toxicity of the extract was performed in mice using doses of 2.0 g/kg intraperitoneally and 5.0 g/kg orally. Blood was removed for laboratory analysis of hematological and biochemical parameters.Results: Bl-EtOH (100, 200 and 400 mg/kg, i.p.) reduced the number of writhing (91.80, 93.44 and 78.68 %, respectively) and the number of paw licks during the first (60.86, 62.84 and 66.79 %) and second phase (91.93, 82.18 and 88.73 %) of the formalin test. Naloxone (1.5 mg/kg, i.p.) antagonized the antinociceptive action of Bl-EtOH (100 mg/kg), and this finding suggests involvement of opioid mechanism. The effect of Bl-EtOH on hot plate response provides a confirmation of its central effect.Conclusion: B. laciniosa leaf extract has antinociceptive properties. Peripheral, and at least in part, central mechanisms, may be involved in this antinociceptive effect. The ethanol leaf extract apparently presents no significant toxicity.Keywords: Bromelia laciniosa, Nociception, Pain, Writhing, Acute toxicit

Correction to: Atypical pathogens in hospitalized patients with community-acquired pneumonia: a worldwide perspective.

An amendment to this paper has been published and can be accessed via the original article

A prospective seroepidemiological study of toxocariasis during early childhood in coastal Ecuador: potential for congenital transmission and risk factors for infection.

BACKGROUND: Although Toxocara spp. infection has a worldwide distribution, to our knowledge, no data from birth cohorts have been reported in published studies on the potential for congenital transmission and determinants of infection in early childhood. METHODS: We followed 290 mother-infant pairs from birth to 5 years of age through periodic collection of data and samples at birth, 7 and 13 months and 2, 3 and 5 years of age. Data on potential risk factors and confounders were collected by maternal questionnaire. Blood for plasma was collected from the mother at time of birth and periodically from the child for detection of anti-Toxocara spp. immunoglobulin G (IgG) antibodies using a Toxocara canis larval excretory-secretory antigen-based enzyme-linked immunosorbent assay. Stool samples were collected from the mother around the time of birth and periodically from the child for microscopic detection of soil-transmitted helminths (STH). Associations between potential risk factors and Toxocara spp. seroprevalence and seroconversion were estimated using multivariable logistic regression and generalized estimating equations. RESULTS: Toxocara spp. seroprevalence was 80.7% in mothers and in children was 0%, 9.3%, 48.4%, 64.9%, and 80.9% at 7 months, 13 months, 2, 3 and 5 years, respectively. Risk factors significantly associated with increases in seroprevalence over the first 5 years of life in multivariable analyses were age [Odds ratio (OR) 2.06, 95% confidence interval (CI) 1.39-2.27, P < 0001], male sex (female vs. male: OR 0.66, 95% CI 0.48-0.89, P = 0.006), maternal ethnicity (non-Afro vs. Afro-Ecuadorian: OR 0.65, 95% CI 0.47-0.91, P = 0.011), lower maternal educational and socioeconomic level, and childhood STH (OR 2.29, 95% CI 1.51-3.47, P < 0.001). Seroconversion rates for infection were greatest at 2 years of age (3.8%/month). Factors associated significantly with seroconversion at 2, 3 or 5 years were childhood STH infection, male sex, and more frequent domestic cat exposure. CONCLUSIONS: Our data, from an area of high Toxocara spp. endemicity, indicate no congenital transmission but high rates of seroconversion after 13 months of age reaching maternal levels of seroprevalence by 5 years of age. Factors associated with seroprevalence and seroconversion included STH infections, domestic cats, maternal ethnicity, male sex, STH infections, and markers of greater poverty

Murine Gamma Herpesvirus 68 Hijacks MAVS and IKKβ to Abrogate NFκB Activation and Antiviral Cytokine Production

Upon viral infection, mitochondrial antiviral signaling (MAVS) protein serves as a key adaptor to promote cytokine production. We report here that murine gamma herpesvirus 68 (γHV68), a model virus for oncogenic human gamma herpesviruses, subverts cytokine production via the MAVS adaptor. During early infection, γHV68 hijacks MAVS and IKKβ to induce the site-specific phosphorylation of RelA, a crucial subunit of the transcriptionally active NFκB dimer, which primes RelA for the proteasome-mediated degradation. As such, γHV68 efficiently abrogated NFκB activation and cytokine gene expression. Conversely, uncoupling RelA degradation from γHV68 infection promoted NFκB activation and elevated cytokine production. Loss of MAVS increased cytokine production and immune cell infiltration in the lungs of γHV68-infected mice. Moreover, exogenous expression of the phosphorylation- and degradation-resistant RelA variant restored γHV68-induced cytokine production. Our findings uncover an intricate strategy whereby signaling via the upstream MAVS adaptor is intercepted by a pathogen to nullify the immediate downstream effector, RelA, of the innate immune pathway

Computational Models for Prediction of Yeast Strain Potential for Winemaking from Phenotypic Profiles

Saccharomyces cerevisiae strains from diverse natural habitats harbour a vast amount of phenotypic diversity, driven by interactions between yeast and the respective environment. In grape juice fermentations, strains are exposed to a wide array of biotic and abiotic stressors, which may lead to strain selection and generate naturally arising strain diversity. Certain phenotypes are of particular interest for the winemaking industry and could be identified by screening of large number of different strains. The objective of the present work was to use data mining approaches to identify those phenotypic tests that are most useful to predict a strain's potential for winemaking. We have constituted a S. cerevisiae collection comprising 172 strains of worldwide geographical origins or technological applications. Their phenotype was screened by considering 30 physiological traits that are important from an oenological point of view. Growth in the presence of potassium bisulphite, growth at 40 degrees C, and resistance to ethanol were mostly contributing to strain variability, as shown by the principal component analysis. In the hierarchical clustering of phenotypic profiles the strains isolated from the same wines and vineyards were scattered throughout all clusters, whereas commercial winemaking strains tended to co-cluster. Mann-Whitney test revealed significant associations between phenotypic results and strain's technological application or origin. Naive Bayesian classifier identified 3 of the 30 phenotypic tests of growth in iprodion (0.05 mg/mL), cycloheximide (0.1 mu g/mL) and potassium bisulphite (150 mg/mL) that provided most information for the assignment of a strain to the group of commercial strains. The probability of a strain to be assigned to this group was 27% using the entire phenotypic profile and increased to 95%, when only results from the three tests were considered. Results show the usefulness of computational approaches to simplify strain selection procedures.Ines Mendes and Ricardo Franco-Duarte are recipients of a fellowship from the Portuguese Science Foundation, FCT (SFRH/BD/74798/2010, SFRH/BD/48591/2008, respectively) and Joao Drumonde-Neves is recipient of a fellowship from the Azores government (M3.1.2/F/006/2008 (DRCT)). Financial support was obtained from FEDER funds through the program COMPETE and by national funds through FCT by the projects FCOMP-01-0124-008775 (PTDC/AGR-ALI/103392/2008) and PTDC/AGR-ALI/121062/2010. Lan Umek and Blaz Zupan acknowledge financial support from Slovene Research Agency (P2-0209). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio

Using Vignettes in Qualitative Research to Explore Barriers and Facilitating Factors to the Uptake of Prevention of Mother-to-Child Transmission Services in Rural Tanzania: A Critical Analysis.

Vignettes are short stories about a hypothetical person, traditionally used within research (quantitative or qualitative) on sensitive topics in the developed world. Studies using vignettes in the developing world are emerging, but with no critical examination of their usefulness in such settings. We describe the development and application of vignettes to a qualitative investigation of barriers to uptake of prevention of mother-to-child transmission (PMTCT) HIV services in rural Tanzania in 2012, and critique the successes and challenges of using the technique in this setting. Participatory Learning and Action (PLA) group activities (3 male; 3 female groups from Kisesa, north-west Tanzania) were used to develop a vignette representing realistic experiences of an HIV-infected pregnant woman in the community. The vignette was discussed during in-depth interviews with 16 HIV-positive women, 3 partners/relatives, and 5 HIV-negative women who had given birth recently. A critical analysis was applied to assess the development, implementation and usefulness of the vignette. The majority of in-depth interviewees understood the concept of the vignette and felt the story was realistic, although the story or questions needed repeating in some cases. In-depth interviewers generally applied the vignette as intended, though occasionally were unsure whether to steer the conversation back to the vignette character when participants segued into personal experiences. Interviewees were occasionally confused by questions and responded with what the character should do rather than would do; also confusing fieldworkers and presenting difficulties for researchers in interpretation. Use of the vignette achieved the main objectives, putting most participants at ease and generating data on barriers to PMTCT service uptake. Participants' responses to the vignette often reflected their own experience (revealed later in the interviews). Participatory group research is an effective method for developing vignettes. A vignette was incorporated into qualitative interview discussion guides and used successfully in rural Africa to draw out barriers to PMTCT service use; vignettes may also be valuable in HIV, health service use and drug adherence research in this setting. Application of this technique can prove challenging for fieldworkers, so thorough training should be provided prior to its use