1,037 research outputs found
Phenoloxidase activity acts as a mosquito innate immune response against infection with semliki forest virus
Several components of the mosquito immune system including the RNA interference (RNAi), JAK/STAT, Toll and IMD pathways have previously been implicated in controlling arbovirus infections. In contrast, the role of the phenoloxidase (PO) cascade in mosquito antiviral immunity is unknown. Here we show that conditioned medium from the Aedes albopictus-derived U4.4 cell line contains a functional PO cascade, which is activated by the bacterium Escherichia coli and the arbovirus Semliki Forest virus (SFV) (Togaviridae; Alphavirus). Production of recombinant SFV expressing the PO cascade inhibitor Egf1.0 blocked PO activity in U4.4 cell- conditioned medium, which resulted in enhanced spread of SFV. Infection of adult female Aedes aegypti by feeding mosquitoes a bloodmeal containing Egf1.0-expressing SFV increased virus replication and mosquito mortality. Collectively, these results suggest the PO cascade of mosquitoes plays an important role in immune defence against arboviruses
Social gradient in the cost of oral pain and related dental service utilisation among South African adults
Background: Oral pain affects people's daily activities and quality of life. The burden of oral pain may vary across
socio-economic positions. Currently, little is known about the social gradient in the cost of oral pain among South
Africans. This study therefore assessed the social gradient in the cost of oral pain and the related dental service
utilisation pattern among South African adults.
Methods: Data were obtained from a nationally representative cross-sectional survey of South African adults
?16 year-old (n = 2651) as part of the South African Social Attitudes Survey conducted by the South African Human
Sciences Research Council. The survey included demographic data, individual-level socio-economic position (SEP),
self-reported oral health status, past six months' oral pain experience and cost. The area-level SEP was obtained
from the 2010 General Household Survey (n = 25,653 households) and the 2010/2011Quarterly Labour Force Survey
conducted in South Africa. The composite indices used for individual-level SEP (? = 0.76) and area-level SEP (? = 0.
88) were divided into tertiles. Data analysis was done using t-tests and ANOVA. Significance was set at p < 0.05.
Results: The prevalence of oral pain among the adult South Africans was 19.4 % (95 % CI = 17.2-21.9). The most
commonly reported form of oral pain was 'toothache' (78.9 %). The majority of the wealthiest participants sought
care from private dental clinics (64.7 %), or from public dental clinics (19.7 %), while the poorest tended to visit a
public dental clinic (45 %) or nurse/general medical practitioner (17.4 %). In the poorest areas, 21 % responded to
pain by 'doing nothing'. The individual expenditure for oral pain showed a social gradient from an average of
ZAR61.44 spent by those of lowest SEP to ZAR433.83 by the wealthiest (national average ZAR170.92). Average time
lost from school/work was two days over the six-month period, but days lost was highest for those living in middle
class neighbourhoods (3.41), while those from the richest neighbourhood had lost significantly fewer days from oral
pain (0.64).
Conclusions: There is a significant social gradient in the burden of oral pain. Improved access to dental care,
possibly through carefully planned universal National Health Insurance (NHI), may reduce oral health disparities in
South Africa.Scopus 201
The Expanding Fireball of Nova Delphini 2013
A classical nova occurs when material accreting onto the surface of a white
dwarf in a close binary system ignites in a thermonuclear runaway. Complex
structures observed in the ejecta at late stages could result from interactions
with the companion during the common envelope phase. Alternatively, the
explosion could be intrinsically bipolar, resulting from a localized ignition
on the surface of the white dwarf or as a consequence of rotational distortion.
Studying the structure of novae during the earliest phases is challenging
because of the high spatial resolution needed to measure their small sizes.
Here we report near-infrared interferometric measurements of the angular size
of Nova Delphini 2013, starting from one day after the explosion and continuing
with extensive time coverage during the first 43 days. Changes in the apparent
expansion rate can be explained by an explosion model consisting of an
optically thick core surrounded by a diffuse envelope. The optical depth of the
ejected material changes as it expands. We detect an ellipticity in the light
distribution, suggesting a prolate or bipolar structure that develops as early
as the second day. Combining the angular expansion rate with radial velocity
measurements, we derive a geometric distance to the nova of 4.54 +/- 0.59 kpc
from the Sun.Comment: Published in Nature. 32 pages. Final version available at
http://www.nature.com/nature/journal/v515/n7526/full/nature13834.htm
Nursing in the hospital accreditation process: practice and implications in the work quotidian
Metabarcoding analysis on European coastal samples reveals new molecular metazoan diversity
Although animals are among the best studied organisms, we still lack a full description of their diversity, especially for microscopic taxa. This is partly due to the time-consuming and costly nature of surveying animal diversity through morphological and molecular studies of individual taxa. A powerful alternative is the use of high-throughput environmental sequencing, providing molecular data from all organisms sampled. We here address the unknown diversity of animal phyla in marine environments using an extensive dataset designed to assess eukaryotic ribosomal diversity among European coastal locations. A multi-phylum assessment of marine animal diversity that includes water column and sediments, oxic and anoxic environments, and both DNA and RNA templates, revealed a high percentage of novel 18S rRNA sequences in most phyla, suggesting that marine environments have not yet been fully sampled at a molecular level. This novelty is especially high among Platyhelminthes, Acoelomorpha, and Nematoda, which are well studied from a morphological perspective and abundant in benthic environments. We also identified, based on molecular data, a potentially novel group of widespread tunicates. Moreover, we recovered a high number of reads for Ctenophora and Cnidaria in the smaller fractions suggesting their gametes might play a greater ecological role than previously suspected
Novel mutations in the voltage-gated sodium channel of pyrethroid-resistant Varroa destructor populations from the Southeastern USA
The parasitic mite Varroa destructor has a significant worldwide impact on bee colony health. In the absence of control measures, parasitized colonies invariably collapse within 3 years. The synthetic pyrethroids tau-fluvalinate and flumethrin have proven very effective at managing this mite within apiaries, but intensive control programs based mainly on one active ingredient have led to many reports of pyrethroid resistance. In Europe, a modification of leucine to valine at position 925 (L925V) of the V. destructor voltage-gated sodium channel was correlated with resistance, the mutation being found at high frequency exclusively in hives with a recent history of pyrethroid treatment. Here, we identify two novel mutations, L925M and L925I, in tau-fluvalinate resistant V. destructor collected at seven sites across Florida and Georgia in the Southeastern region of the USA. Using a multiplexed TaqMan® allelic discrimination assay, these mutations were found to be present in 98% of the mites surviving tau-fluvalinate treatment. The mutations were also found in 45% of the non-treated mites, suggesting a high potential for resistance evolution if selection pressure is applied. The results from a more extensive monitoring programme, using the Taqman® assay described here, would clearly help beekeepers with their decision making as to when to include or exclude pyrethroid control products and thereby facilitate more effective mite management programmes
Linking regulation of practitioner school psychology and the United Nations Convention on the Rights of the Child: The need to build a bridge
Maternal educational level and risk of gestational hypertension: the Generation R Study.
We examined whether maternal educational level as an indicator of socioeconomic status is associated with gestational hypertension. We also examined the extent to which the effect of education is mediated by maternal substance use (that is smoking, alcohol consumption and illegal drug use), pre-existing diabetes, anthropometrics (that is height and body mass index (BMI)) and blood pressure at enrolment. This was studied in 3262 Dutch pregnant women participating in the Generation R Study, a population-based cohort study. Level of maternal education was established by questionnaire at enrolment, and categorized into high, mid-high, mid-low and low. Diagnosis of gestational hypertension was retrieved from medical records using standard criteria. Odds ratios (OR) of gestational hypertension for educational levels were calculated, adjusted for potential confounders and additionally adjusted for potential mediators. Adjusted for age and gravidity, women with mid-low (OR: 1.52; 95% CI: 1.02, 2.27) and low education (OR: 1.30; 95% CI: 0.80, 2.12) had a higher risk of gestational hypertension than women with high education. Additional adjustment for substance use, pre-existing diabetes, anthropometrics and blood pressure at enrolment attenuated these ORs to 1.09 (95% CI: 0.70, 1.69) and 0.89 (95% CI: 0.50, 1.58), respectively. These attenuations were largely due to the effects of BMI and blood pressure at enrolment. Women with relatively low educational levels have a higher risk of gestational hypertension, which is largely due to higher BMI and blood pressure levels from early pregnancy. The higher risk of gestational hypertension in these women is probably caused by pre-existing hypertensive tendencies that manifested themselves during pregnancy
Breast cancer response to neoadjuvant chemotherapy: predictive markers and relation with outcome
The aim of this study was to provide a better insight into breast cancer response to chemotherapy. Chemotherapy improves outcome in breast cancer patients. The effect of cytotoxic treatment cannot be predicted for individual patients. Therefore, the identification of tumour characteristics associated with tumour response and outcome is of great clinical interest. We studied 97 patients, who received anthracycline-based neoadjuvant chemotherapy. Tumour samples were taken prior to and after chemotherapy. We quantified the response to chemotherapy clinically and pathologically and determined histological and molecular tumour characteristics. We assessed changes in the expression of Bcl-2, ER, P53 HER2 and Ki-67. Association with response and outcome was tested for all parameters. The experimental results showed 15 clinical (17%) and three (3%) pathological complete remissions. There were 18 (20%) clinical vs 29 (33%) pathological nonresponders. The expression of most markers was similar before and after chemotherapy. Only Ki-67 was significantly decreased after chemotherapy. Factors correlated with response were: large tumour size, ER negativity, high Ki-67 count and positive P53 status. Tumour response and marker expression did not predict disease-free or overall survival. In conclusion, clinical and pathological response assessments are poorly associated. Proliferation decreases significantly after chemotherapy. ER negativity and a high proliferation index are associated with better response. HER2 status does not predict response, and outcome is not related to tumour response
The range of the golden-mantle tamarin, Saguinus tripartitus (Milne Edwards, 1878): distributions and sympatry of four tamarin species in Colombia, Ecuador, and northern Peru
A detailed understanding of the range of the golden-mantle tamarin, Saguinus tripartitus (Milne Edwards, 1878), in Amazonian Peru and Ecuador is of particular relevance, not only because it is poorly known but also because it was on the basis of its supposed sympatry with the saddleback tamarin (S. fuscicollis lagonotus) that Thorington (Am J Primatol 15:367–371, 1988) argued that it is a distinct species rather than a saddleback tamarin subspecies, as was believed by Hershkovitz (Living new world monkeys, vol I. The University of Chicago Press, Chicago, 1977). A number of surveys have been carried out since 1988 in the supposed range of S. tripartitus, in both Ecuador and Peru. Here we summarize and discuss these issues and provide a new suggestion for the geographic range of this species; that is, between the ríos Napo and Curaray in Peru and extending east into Ecuador. We also review current evidence for the distributions of Spix’s black-mantle tamarin (S. nigricollis nigricollis), Graells’ black-mantle tamarin (S. n. graellsi), and the saddleback tamarin (S. fuscicollis lagonotus), which are also poorly known, and examine the evidence regarding sympatry between them. We conclude that despite the existence of a number of specimens with collecting localities that indicate overlap in their geographic ranges, the fact that the four tamarin species are of similar size and undoubtedly very similar in their feeding habits militates strongly against the occurrence of sympatry among them
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