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Treatment options for Hepatitis C infection have greatly improved with direct-acting antiviral (DAA) combinations achieving high cure rates. Nevertheless, the cost of this treatment is still high and access to treatment in many countries has been preferentially reserved for patients with more severe fibrosis (F3 and F4). In this French nationwide study, we investigated the epidemiological characteristics and genotype distribution of hepatitis C virus (HCV) in treatment-naive patients with METAVIR fibrosis stages between F0 and F2 in order to identify patient profiles that became eligible for unrestricted treatment in a second period. Between 2015 and 2016 we collected data from nine French university hospitals on a total of 584 HCV positive patients with absent, mild or moderate liver fibrosis. The most represented genotypes were genotype 1b (159/584; 27.2%), followed by genotype 1a (150/584; 25.7%); genotype 3 (87/584: 14.9%); genotype 4 (80/584; 13.7%). Among genotype 4: 4a was predominantly encountered with 22 patients (27.5% of genotype 4). Genotypes 1b and 1a are currently the most frequent virus types present in treatment-naive patients with mild fibrosis in France. They can be readily cured using the available DAA. Nevertheless, non-a/non-d genotype 4 is also frequent in this population and clinical data on the efficacy of DAA on these subtypes is missing. The GEMHEP is the French group for study and evaluation of viral hepatitis on a national scale. Data collection on epidemiological and molecular aspects of viral hepatitis is performed on a regular basis in all main French teaching hospitals and serves as a basis for surveillance of these infections. Analysis and trends are regularly published on behalf of the GEMHEP group. Data collection was performed retrospectively over the 2015–2016 period, covering nine main university hospitals in France. A total of 584 hepatitis C positive patients were included in this study. Genotyping of the circulating viruses showed a high prevalence of genotypes 1b and 1a in our population. The epidemiology of hepatitis C is slowly changing in France, particularly as a consequence of the rise of ‘non-a non-d’ genotype 4 viruses mainly originating from African populations. More data concerning treatment efficacy of these genotypes is needed in order to guide clinical care.
Phosphorus and calcium deficiency in horses represents an important factor responsible for the low equine production in Brazil. The basic mechanisms of P and Ca metabolism differ substantially among species. Regulation of P and Ca metabolism is less well understood in horses than in others species. With the use of the isotopic dilution technique is possible to evaluate the metabolism for this mineral. The aim of the present experiment was to study the effect of different Ca levels in the diet on P and Ca metabolism in horses.
The in vitro gas production is a widely used technique for the evaluation of feeds for ruminant animals. Although it measures rate and extension of gas production during feed fermentation in culture medium, rumen inoculum from operated animals (fistulae) is required. Faecal microorganisms function similarly to those in the rumen; they decompose feed and do not require operated animals. The objective of the present experiment was to compare rumen liquor and equine faeces as source of inoculum in the gas production technique.
Concentrate mixtures fed ruminants generally are composed by cereals where phosphorus is present mainly in phytate form or phytin (Maga, 1982). Phytate phosphorus is thought to be completely available to ruminants due to the presence of phytase enzyme that hydrolyzes phytate phosphorus making it available for absorption. Researches have shown that this fact is not always true, depending on different conditions (Park et al., 2000). The aim of this paper was to study the influence of phytate phosphorus on calcium availability.
With the use of radioactive calcium (Ca) it is possible to study the kinetic aspects of Ca metabolism. Research in Brazil has been carried out to study mineral metabolism in sheep and cattle, especially phosphorus, by using isotope dilution techniques. However, there is very little information on Ca metabolism in sheep. The objective of this experiment was to study the effects of various Ca sources on the Ca metabolism in sheep by using isotope and balance techniques.
The close association of calcium and phosphorus in bone, and the narrow relationship between these minerals makes this subject always an important aim of study for researches on animal nutrition (Braithwaite, 1984). The utilization of alternative sources of calcium has been studied in Brazil in the last years however there is a lack of information about the effects of these sources on phosphorus metabolism. The aim of this study was to evaluate phosphorus metabolism in sheep fed four different sources of calcium through determination of true absorption and endogenous faecal loss of phosphorus by using the isotope dilution technique (Vitti et al., 2000).
Bats are ancient hosts of Trypanosoma species and their flying ability, longevity and adaptability to distinct environments indicate that they are efficient dispersers of parasites. Bats from Acre state (Amazon Biome) were collected in four expeditions conducted in an urban forest (Parque Zoobotânico) and one relatively more preserved area (Seringal Cahoeira) in Rio Branco and Xapuri municipalities. Trypanosoma sp. infection was detected by hemoculture and fresh blood examination. Isolated parasite species were identified by the similarity of the obtained DNA sequence from 18S rDNA polymerase chain reaction and reference strains. Overall, 367 bats from 23 genera and 32 species were examined. Chiropterofauna composition was specific to each municipality, although Artibeus sp. and Carollia sp. prevailed throughout. Trypanosoma sp. infection was detected in 85 bats (23·2%). The most widely distributed and prevalent genotypes were (in order) Trypanosoma cruzi TcI, T. cruzi marinkellei, Trypanosoma dionisii, T. cruzi TcIV and Trypanosoma rangeli. At least one still-undescribed Trypanosoma species was also detected in this study. The detection of T. cruzi TcI and TcIV (the ones associated with Chagas disease in Amazon biome) demonstrates the putative importance of these mammal hosts in the epidemiology of the disease in the Acre State.
The snow surface roughness at centimetre and millimetre scales is an important parameter related to wind transport, snowdrifts, snowfall, snowmelt and snow grain size. Knowledge of the snow surface roughness is also of high interest for analyzing the signal from radar sensors such as SAR, altimeters and scatterometers. Unfortunately, this parameter has seldom been measured over snow surfaces. The techniques used to measure the roughness of other surfaces, such as agricultural or sand soils, are difficult to implement in polar regions because of the harsh climatic conditions. In this paper we develop a device based on a laser profiler coupled with a GPS receiver on board a snowmobile. This instrumentation was tested successfully in midre Lovénbreen, Svalbard, in April 2006. It allowed us to generate profiles of 3 km sections of the snow-covered glacier surface. Because of the motion of the snowmobile, the roughness signal is mixed with the snowmobile signal. We use a distance/frequency analysis (the empirical mode decomposition) to filter the signal. This method allows us to recover the snow surface structures of wavelengths between 4 and 50 cm with amplitudes of >1 mm. Finally, the roughness parameters of snow surfaces are retrieved. The snow surface roughness is found to be dependent on the scales of the observations. The retrieved RMS of the height distribution is found to vary between 0.5 and 9.2 mm, and the correlation length is found to be between 0.6 and 46 cm. This range of measurements is particularly well adapted to the analysis of GHz radar response on snow surfaces.
Good progress in crop husbandry and science requires that impacts of field-scale interventions can be measured, analysed and interpreted easily and with confidence. The term ‘agronōmics’ describes the arena for research created by field-scale digital technologies where these technologies can enable effective commercially relevant experimentation. Ongoing trials with ‘precision-farm research networks’, along with new statistical methods (and associated software), show that robust conclusions can be drawn from digital field-scale comparisons, but they also show significant scope for improvement in the validity, accuracy and precision of digital measurements, especially those determining crop yields.
Triticale has a reputation for performing well on poor soils, under drought and with reduced inputs, but there has been little investigation of its performance on the better yielding soils dominated by wheat production. The present paper reports 16 field experiments comparing wheat and triticale yield responses to nitrogen (N) fertilizer on high-yielding soils in the UK in harvest years 2009–2014. Each experiment included at least two wheat and at least two triticale varieties, grown at five or six N fertilizer rates from 0 to at least 260 kg N/ha. Linear plus exponential curves were fitted to describe the yield response to N and to calculate economically optimal N rates. Normal type curves with depletion were used to describe protein responses to N. Whole crop samples from selected treatments were taken prior to harvest to measure crop biomass, harvest index, crop N content and yield components. At commercial N rates, mean triticale yield was higher than the mean wheat yield at 13 out of 16 sites; the mean yield advantage of triticale was 0·53 t/ha in the first cereal position and 1·26 t/ha in the second cereal position. Optimal N requirement varied with variety at ten of the 16 sites, but there was no consistent difference between the optimal N rates of wheat and triticale. Triticale grain had lower protein content and lower specific weight than wheat grain. Triticale typically showed higher biomass and straw yields, lower harvest index and higher total N uptake than wheat. Consequently, triticale had higher N uptake efficiency and higher N use efficiency. Based on this study, current N fertilizer recommendations for triticale in the UK are too low, as are national statistics and expectations of triticale yields. The implications of these findings for arable cropping and cereals markets in the UK and Northern Europe are discussed, and the changes which would need to occur to allow triticale to fulfil a role in achieving sustainable intensification are explored.
Brief review of AGNs observations in the X-ray / soft gamma-ray bands with the orbital observatory GRANAT is presented.
For three well known bright objects (3C273, NGC4151 and Cen A) broad band (3 keV–few hundreds keV) spectra have been obtained. Imaging capabilities allowed accurate (several arcminutes) identification of these objects with sources of hard X-rays.
The spectrum of NGC4151 above ≈ 50 keV was found to be much steeper than that in most of the previous observations, while in standard X-ray band the spectrum agrees with observed previously. The comparison of the observed spectra with that of the X-Ray Background (XRB) indicates that sources similar to NGC4151 could reproduce the shape of XRB spectrum in 3–60 keV band.
Cen A was observed in the very low state during most of observations in 1990–1993, except for two observations in 1991. The variability of the hard X-ray flux has been detected on the time scales of several days.
Eight winter oilseed rape and two spring oilseed rape field experiments were performed in the UK in harvest years 2009–12. Each experiment consisted of at least one hybrid and one open-pollinated variety grown at five seed rates from 10 or 20 seeds/m2 to 160 or 200 seeds/m2. Linear plus exponential curves were used to describe the yield response to seed rate and to calculate economically optimal seed rates. Plant counts were then used to derive optimal plant population densities. These ranged from <10 to 39 plants/m2 for six winter oilseed rape experiments between 73 and >155 plants/m2 in two winter oilseed rape experiments with severe spring droughts, and from 47 to 65 plants/m2 for spring oilseed rape. Optimal plant population densities were lower for hybrid than for open-pollinated varieties, due to a combination of the higher cost of hybrid seed and, for some experimental sites, hybrid varieties compensating better for low plant populations. Across all sites, sowing winter oilseed rape at 30 seeds/m2 rather than common commercial rates of 70 seeds/m2 for hybrids and 100 seeds/m2 for open-pollinated varieties would have increased average gross margin by £29/ha. Sowing spring oilseed rape at 70 seeds/m2 rather than commonly used rates of 120 or 150 seeds/m2 would have increased average gross margin by £64/ha.
The mango blossom gall midge, Procontarinia mangiferae, is a multivoltine species that induces galls in inflorescences and leaves of the mango tree, Mangifera indica. In subtropical Reunion Island, populations of P. mangiferae are observed all-year round, but the pattern and the role of dormancy in their life cycle have never been documented. We performed field and laboratory experiments using more than 15,000 larvae. We demonstrated that a larval diapause may affect a part of the midge population, regardless of the season. The total duration of the diapause varied from 6 weeks to more than 1 year. One year of field monitoring showed that the highest incidence of diapause was observed in larvae collected during the summer from mango leaves, where it affected approximately one-third of the individuals. This facultative diapause allows the permanent presence of P. mangiferae in the orchards. By recording diapause duration during 22 weeks under controlled conditions, we showed that high temperatures (26 °C) increased diapause duration and extended the range of the dates of diapause emergence, whereas cool temperatures (20 °C) shortened diapause duration and shortened the range of the dates of emergence from diapause. A temperature decrease from 26 to 20 °C triggered the emergence of diapausing individuals. These mechanisms ensure the synchronization of the emergence of diapausing individuals with the appearance of mango inflorescences, which is also induced by cool winter temperatures.
The global population of jaguars Panthera onca has decreased significantly since the beginning of the 20th century. Given the scarcity of demographic and biological information, estimating population parameters is critical for the design of conservation measures. The jaguar's elusive behaviour makes it impossible to estimate and monitor populations by direct observation. We propose a non-invasive genetic sampling approach and demonstrate its potential for large-scale monitoring. Sex identification was optimized for faecal samples of jaguars and other felids. We also optimized a set of 11 microsatellite markers for reliable identification of individuals. We estimated the effectiveness of faecal sample genotyping in two distinct Brazilian biomes: the Pantanal and the semi-arid Caatinga. Almost 90% of the samples that were molecularly identified as jaguar (n = 90) were successfully genotyped and were assigned to 30 individuals. Genetic diversity was generally high but was significantly lower in the Caatinga population. We show that non-invasive genetic sampling can be a reliable tool to study population parameters and to monitor the genetic status of jaguar populations in different habitats. It may also be useful for future surveys of jaguars that address ecological, behavioural and conservation issues, and could provide a baseline for non-invasive genetic studies of other wild felid populations.
The aim of the present study was to evaluate the effects on yield, oil concentration and nitrogen (N) uptake efficiency of N fertilizer applied to the foliage of oilseed rape during and soon after flowering. Four field experiments were conducted in the UK during the 2008/09 and 2009/10 seasons which investigated six rates of soil-applied N (ammonium nitrate) ranging from 0 to 280 or 320 kg N/ha with each treatment followed by 0 or 40 kg/ha of foliar N applied as a solution of urea at the end of flowering. Each experiment also investigated five rates of foliar N ranging from 0 to 120 kg N/ha applied at the end of flowering and five timings of foliar N (40 kg N/ha) from mid-flowering to 2 weeks after the end of flowering.
Foliar N at 40 kg N/ha applied at the end of flowering significantly increased the seed yield in three of the four experiments. The seed yield increase across all four experiments was 0·25 t/ha (range of 0–0·41 t/ha). In two experiments, the increase in seed yield in response to foliar N occurred irrespective of whether it followed sub-optimal or super-optimal rates of soil-applied N; in one experiment there was a greater response at sub-optimal soil-applied N rates. The foliar N treatment reduced the seed oil concentration by 11 g/kg and increased seed protein concentration by 11 g/kg. Similar yield responses were observed for foliar N applications between mid-flowering and 2 weeks after the end of flowering. The efficiency with which foliar N was taken up into the plant varied between 0 and 100% with an average uptake efficiency across the four experiments of 61%.
Bacterial meningitis is an infection of the central nervous system characterised by strong inflammatory response. The brain is highly dependent on ATP, and the cell energy is obtained through oxidative phosphorylation, a process which requires the action of various respiratory enzyme complexes and creatine kinase (CK) as an effective buffering system of cellular ATP levels in tissues that consume high energy.
Evaluate the activities of mitochondrial respiratory chain complexes I, II, III, IV and CK activity in hippocampus and cortex of the Wistar rat submitted to meningitis by Klebsiella pneumoniae.
Adult Wistar rats received either 10 µl of sterile saline as a placebo or an equivalent volume of K. pneumoniae suspension. The animals were killed in different times at 6, 12, 24 and 48 h after meningitis induction. Another group was treated with antibiotic, starting at 16 h and continuing daily until their decapitation at 24 and 48 h after induction.
In the hippocampus, the meningitis group without antibiotic treatment, the complex I was increased at 24 and 48 h, complex II was increased at 48 h, complex III was inhibited at 6, 12, 24 and 48 h and in complex IV all groups with or without antibiotic treatment were inhibited after meningitis induction, in the cortex there was no alteration.
Although descriptive, our results show that antibiotic prevented in part the changes of the mitochondrial respiratory chain. The meningitis model could be a good research tool to study the biological mechanisms involved in the pathophysiology of the K. pneumoniae meningitis.
Toxoplasma gondii stimulates a potent pro-inflammatory response and neutrophils are involved in early infection. Galectin-3 (Gal-3) is an endogenous modulator of inflammatory processes and anti-infective agents, but its interaction with neutrophils in T. gondii infection is still unclear. Here, we evaluated the role of Gal-3 in peritoneal inflammation, reactive oxygen species (ROS) production by neutrophils and survival, after in vivo T. gondii infection with virulent RH strain, using Gal-3 deficient and wild type mice. Animals were inoculated with thioglycollate or tachyzoites, and peritoneal cells were harvested for analysis of the influx of leukocytes. Neutrophils were isolated from peritoneal exudates from infected mice and stimulated with phorbol myristate acetate (PMA) to evaluate ROS production by luminol-dependent chemiluminescence assay. Our results showed that: (1) Gal-3 upregulates peritoneal inflammation, with enhanced recruitment of neutrophils and lymphocytes after thioglycollate stimulation, but does not influence the enhanced neutrophil influx after early T. gondii infection; (2) Gal-3 upregulates ROS generation by inflammatory peritoneal neutrophils from infected mice, but downregulates its production in non-infected mice and (3) Gal-3 does not influence the survival of mice after infection with the virulent T. gondii strain. In conclusion, Gal-3 is essential for ROS generation by neutrophils in the initial acute phase of T. gondii infection and this phenomenon may constitute an attempt to control parasite growth during in vivo infection with the T. gondii virulent strain.
In this study, we investigated the microbial community (bacteria and protozooplankton) of a Brazilian reservoir that receives neutralized acid mine drainage flowing from piles of earth produced during uranium extraction. Thus, this research represents an attempt to fill a gap in the information on the ecology of freshwater microorganisms in tropical oligotrophic habitats, in particular in systems affected by high levels of the uranium. During the study, we observed very low chlorophyll a contents and protozooplankton cell densities and biomass. These cell densities were between 0 and 89 cells L−1 and were lower than those frequently reported for oligotrophic freshwater lakes. In contrast, bacterial densities were normal or even slightly high, between 1.85 to 6.0 × 109 cells L−1. The present study has demonstrated very low protozooplankton cell densities and biomass in oligotrophic reservoir under the influence of acidic mining eﬀuents and of high levels of ionizing radiation. It is likely that the ciliate cell densities and biomasses recorded in this study, which fall significantly below the previously published values, can be explained by the chronic fractionated exposure of these protozoa to the high levels of uranium to this system.