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The epidemiology of H5N1 and H7N9 avian viruses of humans infected in China differs despite both viruses being avian reassortants that have inherited six internal genes from a common ancestor, H9N2. The median age of infected populations is substantially younger for H5N1 virus (26 years) compared with H7N9 virus (63 years). Population susceptibility to infection with seasonal influenza is understood to be influenced by cross-reactive CD8+ T cells directed towards immunogenic peptides derived from internal viral proteins which may provide some level of protection against further influenza infection. Prior exposure to seasonal influenza peptides may influence the age-related infection patterns observed for H5N1 and H7N9 viruses. A comparison of relatedness of immunogenic peptides between historical human strains and the two avian emerged viruses was undertaken for a possible explanation in the differences in age incidence observed. There appeared to be some relationship between past exposure to related peptides and the lower number of H5N1 virus cases in older populations, however the relationship between prior exposure and older populations among H7N9 virus patients was less clear.
PUFA might modulate inflammatory responses involved in the development of severe dengue. We aimed to examine whether serum PUFA concentrations in patients diagnosed with dengue fever (DF) were related to the risk of progression to dengue haemorrhagic fever/dengue shock syndrome (DHF/DSS). A secondary aim was to assess correlations between fatty acids (FA) and inflammatory biomarkers in patients with DF. We conducted a prospective case–control study nested within a cohort of patients who were diagnosed with DF and followed during the acute episode. We compared the distribution of individual FA (% of total FA) at onset of fever between 109 cases who progressed to DHF/DSS and 235 DF non-progressing controls using unconditional logistic regression. We estimated correlations between baseline FA and cytokine concentrations and compared FA concentrations between the acute episode and >1 year post-convalescence in a subgroup. DHA was positively related to progression to DHF/DSS (multivariable adjusted OR (AOR) for DHA in quintile 5 v. 1=5·34, 95 % CI 2·03, 14·1; Ptrend=0·007). Dihomo-γ-linolenic acid (DGLA) was inversely associated with progression (AOR for quintile 5 v. 1=0·30, 95 % CI 0·13, 0·69; Ptrend=0·007). Pentadecanoic acid concentrations were inversely related to DHF/DSS. Correlations of PUFA with cytokines at baseline were low. PUFA were lower during the acute episode than in a disease-free period. In conclusion, serum DHA in patients with DF predicts higher odds of progression to DHF/DSS whereas DGLA and pentadecanoic acid predict lower odds.
In this outbreak, 12 patients in intensive care units acquired a Chryseobacterium indologenes infection. Cultures from sinkholes and air samples were positive for C. indologenes. After removing wash basins, no new cases appeared. Sinkholes, potentially contaminated, can act as a reservoir for C. indologenes and other microorganisms. Thus, patients and equipment should be protected from sink splashes to avoid contamination.
Oxidative stress has been linked to many obesity-related conditions among children including cardiovascular disease, diabetes mellitus and hypertension. Exposure to environmental chemicals such as phthalates, ubiquitously found in humans, may also generate reactive oxygen species and subsequent oxidative stress. We examined longitudinal changes of 8-isoprostane urinary concentrations, a validated biomarker of oxidative stress, and associations with maternal prenatal urinary concentrations of phthalate metabolites for 258 children at 5, 9 and 14 years of age participating in a birth cohort residing in an agricultural area in California. Phthalates are endocrine disruptors, and in utero exposure has been also linked to altered lipid metabolism, as well as adverse birth and neurodevelopmental outcomes. We found that median creatinine-corrected 8-isoprostane concentrations remained constant across all age groups and did not differ by sex. Total cholesterol, systolic and diastolic blood pressure were positively associated with 8-isoprostane in 14-year-old children. No associations were observed between 8-isoprostane and body mass index (BMI), BMI Z-score or waist circumference at any age. Concentrations of three metabolites of high molecular weight phthalates measured at 13 weeks of gestation (monobenzyl, monocarboxyoctyl and monocarboxynonyl phthalates) were negatively associated with 8-isoprostane concentrations among 9-year olds. However, at 14 years of age, isoprostane concentrations were positively associated with two other metabolites (mono(2-ethylhexyl) and mono(2-ethyl-5-carboxypentyl) phthalates) measured in early pregnancy. Longitudinal data on 8-isoprostane in this pediatric population with a high prevalence of obesity provides new insight on certain potential cardiometabolic risks of prenatal exposure to phthalates.
Chagas disease is a complex zoonosis that affects around 8 million people worldwide. This pathology is caused by Trypanosoma cruzi, a kinetoplastid parasite that shows tremendous genetic diversity evinced in six distinct Discrete Typing Units (TcI-TcVI) including a recent genotype named as TcBat and associated with anthropogenic bats. TcI presents a broad geographical distribution and has been associated with chronic cardiomyopathy. Recent phylogenetic studies suggest the existence of two genotypes (Domestic (TcIDom) and sylvatic TcI) within TcI. The understanding of the course of the infection in different mouse models by these two genotypes is not yet known. Therefore, we infected 126 animals (ICR-CD1, National Institute of Health (NIH) and Balb/c) with two TcIDom strains and one sylvatic strain for a follow-up period of 60 days. We quantified the parasitaemia, immune response and histopathology observing that the maximum day of parasitaemia was achieved at day 21 post-infection. Domestic strains showed higher parasitaemia than the sylvatic strain in the three mouse models; however in the survival curves Balb/c mice were less susceptible to infection compared with NIH and ICR-CD1. Our results suggest that the genetic background plays a fundamental role in the natural history of the infection and the sympatric TcI genotypes have relevant implications in disease pathogenesis.
Magnetically active late-type stars have inhomogeneities on their surfaces that cause various observable effects in the spectral lines and light curves. Such inhomogeneities are magnetic starspots, plages etc. in active regions on the photospheric and chromospheric level. The variations of the spectral lines and light curves originating in these inhomogeneities undergo modulations following stellar rotation.
Hair may be a useful matrix to detect cumulative cortisol concentrations in studies of animal welfare and chronic stress. The aim of this study was to validate a protocol for cortisol detection in hair from dairy cattle by enzyme immunoassay (EIA). Seventeen adult Holstein–Friesian dairy cows were used during the milking period. Hair cortisol concentration was assessed in 25-day-old hair samples taken from the frontal region of the head, analysing black and white coloured hair separately. Concentrations of cortisol metabolites were determined in faeces collected twice a week during the same period of time. There was a high correlation between cortisol values in faeces and cortisol in white colour hair samples but such correlation was not significant with the black colour hair samples. The intra- and inter-assay coefficients of variation were 4.9% and 10.6%, respectively. The linearity showed R2=0.98 and mean percentage error of −10.8±1.55%. The extraction efficiency was 89.0±23.52% and the parallelism test showed similar slopes. Cortisol detection in hair by using EIA seems to be a valid method to represent long-term circulating cortisol levels in dairy cattle.
People with dementia are extremely vulnerable in hospital and unscheduled
admissions should be avoided if possible.
To identify any predictors of general hospital admission in people with
dementia in a well-characterised national prospective cohort study.
A cohort of 730 persons with dementia was drawn from the Scottish
Dementia Research Interest Register (47.8% female; mean age 76.3 years,
s.d. = 8.2, range 50–94), with a mean follow-up period of 1.2 years.
In the age- and gender-adjusted multivariable model (n =
681; 251 admitted), Neuropsychiatric Inventory score (hazard ratio per
s.d. disadvantage 1.21, 95% CI 1.08–1.36) was identified as an
independent predictor of admission to hospital.
Neuropsychiatric symptoms in dementia, measured using the
Neuropsychiatric Inventory, predict non-psychiatric hospital admission of
people with dementia. Further studies are merited to test whether
interventions to reduce such symptoms might reduce unscheduled admissions
to acute hospitals.
Two of the problems that currently affect a large proportion of university students are high levels of anxiety and stress experienced in different situations, which are particularly high during the first years of their degree and during exam periods. The present study aims to investigate whether mindfulness training can bring about significant changes in the manifestations of depression, anxiety, and stress of students when compared to another group undergoing a physical activity program and a control group. The sample consisted of 125 students from the Bachelor of Education Program. The measuring instrument used was the Abbreviated Scale of Depression, Anxiety and Stress (DASS-21). The results indicate that the effects of reducing the identified variables were higher for the mindfulness group than for the physical education group and for the control group F(2) = 5.91, p = .004, η2 = .106. The total scores for all variables related to the mindfulness group decreased significantly, including an important stress reduction t(29) = 2.95, p = .006, d = .667. Mindfulness exercises and some individual relaxing exercises involving Physical Education could help to reduce manifestations of stress and anxiety caused by exams in students.
Stoichiometric 4H-SrMnO3.0 nanoparticles have been successfully synthesized for the first time from thermal decomposition of a new heterometallic precursor [SrMn(edta)(H2O)5]·3/2H2O. From this precursor, highly homogeneous 4H-SrMnO3.0 nanoparticles with average particle size 70 nm are obtained. Local structural information, provided by atomically-resolved microscopy techniques, shows that 4H-SrMnO3.0 nanoparticles exhibit the same general structural features than the bulk material, although structural disorder, due to edge-dislocations, is observed. The nanometric size of particles enables a topotactic reduction process at low temperature stabilizing a metastable 4H-SrMnO2.82 phase. The oxygen deficiency is accommodated through extra cubic layers breaking the …hchc… 4H-sequence. These defect areas are Mn3+ rich as evidenced by high energy resolution EELS data. Magnetic characterization of nano-4H-SrMnO3-δ shows significant variations with respect to the bulk material.
In this work we review the aggregation of variables method for discrete dynamical
systems. These methods consist of describing the asymptotic behaviour of a complex system
involving many coupled variables through the asymptotic behaviour of a reduced system
formulated in terms of a few global variables. We consider population dynamics models
including two processes acting at different time scales. Each process has associated a map
describing its effect along its specific time unit. The discrete system encompassing both
processes is expressed in the slow time scale composing the map associated to the slow one
and the k-th iterate of the map associated to the fast one. In the linear case a result is
stated showing the relationship between the corresponding asymptotic elements of both
systems, initial and reduced. In the nonlinear case, the reduction result establishes the
existence, stability and basins of attraction of steady states and periodic solutions of
the original system with the help of the same elements of the corresponding reduced
system. Several models looking over the main applications of the method to populations
dynamics are collected to illustrate the general results.
We present a mathematical model of a fishery on several sites with a variable price. The
model takes into account the evolution during the time of the resource, fishes and boats
movements between the different sites, fishing effort and price that varies with respect
to supply and demand. We suppose that boats and fishes movements as well as prices
variations occur at a fast time scale. We use methods of aggregation of variables in order
to reduce the number of variables and we derive a reduced model governing two global
variables, respectively the biomass of the resource and the fishing effort of the whole
fishery. We look for the existence of equilibria of the aggregated model. We show that the
aggregated model can have 1, 2 or 3 non trivial equilibria. We show that a variation of
the total number of sites can induce a switch from over-exploitation to sustainable
The release of chemicals following herbivore grazing on primary producers may provide
feeding cues to carnivorous predators, thereby promoting multitrophic interactions. In
particular, chemicals released following grazing on phytoplankton by microzooplankton
herbivores have been shown to elicit a behavioural foraging response in carnivorous
copepods, which may use this chemical information as a mechanism to locate and remain
within biologically productive patches of the ocean. In this paper, we use a 1D spatial
reaction-diffusion model to simulate a tri-trophic planktonic system in the water column,
where predation at the top trophic level (copepods) is affected by infochemicals released
by the primary producers forming the bottom trophic level. The effect of the
infochemical-mediated predation is investigated by comparing the case where copepods
forage randomly to the case where copepods adjust their vertical position to follow the
distribution of grazing-induced chemicals. Results indicate that utilization of
infochemicals for foraging provides fitness benefits to copepods and stabilizes the system
at high nutrient load, whilst also forming a possible mechanism for phytoplankton bloom
formation. We also investigate how the copepod efficiency to respond to infochemicals
affects the results, and show that small increases (2%) in the ability of copepods to
sense infochemicals can promote their persistence in the system. Finally we argue that
effectively employing infochemicals for foraging can be an evolutionarily stable strategy
A recently proposed model for the investigation of diffusivity in planktonic systems
containing toxin-producing phytoplanktons is here reconsidered. We show the existence of
planktonic travelling waves. Numerical simulations validate the analytical findings, to
elucidate the sensitivity of the results in dependence of the diffusion coefficients.
Studying and understanding the sources of variation in early life traits in farmed deer are fundamental for management and/or breeding purposes. Data from a captive white-tailed deer population were analysed to identify non-genetic and genetic factors affecting the birth weight (BW) of fawns. The year, type of birth and sex were included in a fixed linear model to examine their significance. All of the examined non-genetic factors had a highly significant effect on BW (P<0·001). The examined years showed variation attributed to food availability affecting the gestational conditions of does. Male fawns were 193 g heavier than female fawns at birth (P<0·001), and singleton births were associated with a higher BW (2·97±0·043 kg) compared with twin (−0·261 g) and triplet (−0·642 g) fawning (P<0·001). The best-fitting animal model was selected by comparing reduced and complete models. Based on the selected animal model, which included direct genetic and common maternal effects, genetic components and parameters were estimated. The direct heritability was found to be 0·28±0·126, and a small but important contribution of common maternal environmental effects was identified (c2=0·15±0·062). The results support the importance of certain environmental factors affecting BW and indicate the relevance of direct genetic and maternal environmental influences to sustained genetic changes in BW and positively correlated traits in farmed white-tailed deer populations.
Since their discovery, four species of human bocavirus (HBoV) have been described in patients with respiratory and gastrointestinal diseases. However, a clear causal association between HBoV-1 and gastroenteritis has not been demonstrated. In this study, we describe the detection and quantification of HBoV-1 in stools from children with acute non-bacterial gastroenteritis using quantitative polymerase chain reaction. HBoV-1 genome was detected in 10·6% of stools with frequent association with rotavirus and norovirus. The median of HBoV-1 viral load was 1·88 × 104 genome/ml, lower than previously shown in secretions of patients with respiratory infections, without any obvious association between high viral load and presence of HBoV as single agent. Thus, although HBoV-1 was frequently detected in these patients, there is no clear causal association of this agent with diarrhoea. Indeed, HBoV-1 DNA in stools of patients with gastroenteritis without respiratory symptoms may be a remnant of previous infections or associated with prolonged shedding of virus in the respiratory or digestive tracts.
This article describes a new principle of transduction involving an heterojunction between a Molecular Semiconductor and a Doped Insulator (MSDI). Herein, we report on an MSDI-based sensor featuring an heterojunction between a lutetium bisphthalocyanine (LuPc2), which acts as Molecular Semiconductor (MS) and a thin film of Doped Insulator (DI) made of substituted or fluorinated copper phthalocyanine (CuFnPc, where n = 0, 8, 16). Previously, we reported the peculiar effect of the heterojunction on the MSDI’s electronic behavior, suggesting this device as a new kind of transducer for gas chemosensing. Indeed, of particular significance was the key role of modulator played by the nature of the doped insulator sub-layer. While the MS thin film remains the only layer of the sensor exposed to gas atmosphere, the DI’s ability to tune the electronic characteristics of the organic heterojunction allows it to drastically affect the nature of the effective charge carriers. In particular, an increase in fluorination of the doped insulator can cause an inversion of the LuPc2 response toward electron accepting (ozone, ppb level) or donating (ammonia, ppm level) gases. The present work focuses on the structural, electronic and electrical properties of the MSDI heterojunction, which have been studied by UV-vis spectroscopy, atomic force microscopy, current-voltage measurements and chemical doping, in order to shed some light on this phenomenon. The unique ambipolar nature of LuPc2 is suggested to be the main property responsible for the MSDI’s unique behavior.