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91.
BackgroundEarly diagnosis of bacteremia and sepsis in pediatric oncology patients with febrile neutropenia still remains unresolved task due to lack of sensitive and specific laboratory markers particularly at the beginning of the infectious process. The objective of our study was to assess the potentiality of interleukin-10 (IL-10) to predict or exclude bacteremia or sepsis at the beginning of febrile episode in childhood oncology patients.MethodsA total of 36 febrile neutropenic episodes in 24 children were studied. Serum samples were collected after confirmation of febrile neutropenia and analyzed using automated random access analyzer.ResultsThe sensitivity of IL-10 was 73% and specificity – 92% (cut-off = 18 pg/ml, area under the curve – 0.87, 95% CI for sensitivity 39–94%, 95% CI for specificity 74–99%) with negative predictive value (NPV) – 83%.ConclusionsIL-10 evaluation might be used as an additional diagnostic tool for clinicians in excluding bacteremia or clinical sepsis in oncology patients with febrile neutropenia because of high NPV and specificity.  相似文献   
92.
Parasitoid fitness is influenced by the ability to overcome host defense strategies and by the ability of parasitoid females to select high‐quality host individuals. When females are unable to differentiate among hosts, their fitness will decrease with an increasing abundance of resistant hosts. To understand the effect of mixed host populations on female fitness, it is therefore necessary to investigate the ability of female parasitoids to select among hosts. Here, we used behavioral assays, headspace volatile collection, and electrophysiology to study the ability of Asecodes parviclava to use olfactory cues to select between a susceptible host (Galerucella calmariensis) and a resistant host (Galerucella pusilla) from a distance. Our studies show that parasitoid females have the capacity to distinguish the two hosts and that the selection behavior is acquired through experiences during earlier life stages. Further, we identified two volatiles (α‐terpinolene and [E]‐β‐ocimene) which amounts differ between the two plant–herbivore systems and that caused behavioral and electrophysiological responses. The consequence of this selection behavior is that females have the capacity to avoid laying eggs in G. pusilla, where the egg mortality is higher due to much stronger immune responses toward A. parviclava than in larvae of Gcalmariensis.  相似文献   
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94.
Co-infections are prevalent worldwide, however, we are still struggling to understand interactions between different parasites and their impacts on host fitness. In the present experimental study we analysed the infection dynamics of two avian malarial parasites Plasmodium elongatum (genetic lineage pERIRUB01) and Plasmodium relictum (genetic lineage pSGS1) and their impacts on host health during single and co-infections. We reveal that P. elongatum intensity of parasitemia is enhanced by the presence of P. relictum during co-infection, while the parasitemia of P. relictum stays the same. This illustrates how development of a parasite (P. elongatum) which infects both mature and young (polychromatic) red blood cells (RBCs) is facilitated during co-infection with a parasite which specialises in adult RBCs only (P. relictum). The virulence of co-infections was similar to that of the more virulent parasite (P. elongatum). However, the profile of infection and the mechanisms that caused mortality were different. Birds infected with P. elongatum only start to die due to non-regenerative anaemia, when intensity of parasitemia is light and the number of polychromatic RBCs decrease dramatically. Meanwhile, co-infected birds start to die when the mean intensity of parasitemia reaches 10% and the number of polychromatic RBCs increases abnormally, reflecting regenerative anaemia. Our findings reveal that typically measured parameters of virulence (e.g., mortality rate, level of hematocrit) can be the same during single and co-infections, but the mechanisms responsible for the observed virulence can be different. This information serves a better understanding of the processes underpinning the interactions of co-infected parasite species.  相似文献   
95.
Ixodes ricinus (Linnaeus 1758) and Ixodes persulcatus (Schulze 1930) ticks are involved in the transmission of a wide variety of pathogens with considerable impact on human and animal health. The co‐distribution zone of these two tick species is situated in the Baltic countries, which provides a special setting for the population studies. In the present study, genetic variability of I. ricinus ticks collected in allopatric and sympatric locations in the Baltic countries has been investigated using a sequence analysis of the mitochondrial DNA control region, 16S rRNA and cytb genes. There were 32 haplotypes (Hd: 0.8551) and 27 haplotypes (Hd:0.8213) of control region sequences from ticks in allopatric and sympatric zones detected, respectively. Out of 47 16S rRNA gene haplotypes, 32 haplotypes (Hd: 0.7213) were found in the allopatric zone and 27 (Hd:0.9572) in the sympatric zone. The Cytb gene was very conserved and monomorphic in ticks from the allopatric zone, whereas three unique haplotypes were observed in the sympatric zone. The higher number of unique haplotypes of the control region was detected in the allopatric zone. Median joining network and Fst analysis did not reveal a clear separation between ticks from the two zones.  相似文献   
96.
In this paper we review the earliest Secale (rye) records, both pollen and macroremains, from the eastern Baltic region (northeast Poland, Lithuania, Latvia, Estonia and Finland) in order to understand the processes evident in the beginnings of rye cultivation. By taking note of the abundance of recovered Secale grains and pollen in relation to other cereals found in published archaeobotanical data, we try to understand when rye began to be used regionally as a staple food. The clarification of the timing of Secale in the East Baltic, that had social and economic implications, is of particular importance. In this publication we also present a radiocarbon date directly derived from dating a Secale grain from a Roman period hillfort in Lithuania. The date obtained constitutes the earliest record of Secale in the eastern Baltic region, showing that rye cultivation traditions and concomitant innovations in agricultural technology started there much earlier than previously suggested.  相似文献   
97.
Populations worldwide have been increasingly affected by allergic rhinitis associated with pollen allergens. Alterations in the geographical distribution of pollinating flora resulting from climatic changes and increased production of pollens caused by higher atmospheric CO2, have changed the environment in which humans reside. This study, carried out in Lithuania, aimed to demonstrate how people with pollen allergy are affected by symptoms associated with changing pollen loads and to evaluate the resultant changes in human quality of life. This study assessed pollen loads in Lithuania during 2013–2014. Skin prick tests were carried out on 665 individuals aiming to evaluate sensitivity to pollen allergens. Self-reports on symptoms and their impact on quality of life were collected from each study subject. There were 24× to 42× differences in inter-annual peaks of Betula pollen concentrations, while differences of plant pollen concentrations of the other genus/families varied from 1.5 to 92 % on peak days. Positive reactions to pollen allergens were reported in 54 % of the study subjects; 90 % of these subjects had been continuously suffering from moderate-to-severe symptoms of allergic rhinitis. The most frequently reported symptoms were sneezing (99 %), runny nose (98 %) and stuffy nose (97 %). The dominant group of subjects reported symptoms during the entire period of vegetation (7 months). This study demonstrated that people with pollen allergies have attributed symptom-associated worsening of their quality of life to the typical periods of unavoidable exposure and have made only minimal changes in their lifestyle during the season of pollen load.  相似文献   
98.
99.
Many insects face the challenge to select oviposition sites in heterogeneous environments where biotic and abiotic factors can change over time. One way to deal with this complexity is to use sensory experiences made during developmental stages to locate similar habitats or hosts in which larval development can be maximized. While various studies have investigated oviposition preference and larval performance relationships in insects, they have largely overlooked that sensory experiences made during the larval stage can affect such relationships. We addressed this issue by determining the role of natal experience on oviposition preference and larval performance relationships in a tritrophic system consisting of Galerucella sagittariae, feeding on the two host plants Potentilla palustris and Lysimachia thyrsiflora, and its larval parasitoid Asecodes lucens. We firstly determined whether differences in host‐derived olfactory information could lead to divergent host selection, and secondly, whether host preference could result in higher larval performance based on the natal origin of the insects. Our results showed that the natal origin and the quality of the current host are both important aspects in oviposition preference and larval performance relationships. While we found a positive relationship between preference and performance for natal Lysimachia beetles, natal Potentilla larvae showed no such relationship and developed better on L. thyrsiflora. Additionally, the host selection by the parasitoid was mainly affected by the natal origin, while its performance was higher on Lysimachia larvae. With this study, we showed that the relationship between oviposition preference and larval performance depends on the interplay between the natal origin of the female and the quality of the current host. However, without incorporating the full tritrophic context of these interactions, their implication in insect fitness and potential adaptation cannot be fully understood.  相似文献   
100.
The aim of this study was to evaluate the variation of essential oils composition of Bidens tripartita L. collected during three successive years (2009–2011). Essential oils were obtained by supercritical CO2 extraction, applying gas chromatographic–mass spectrometric (GC–MS) analysis for identification of volatile compounds afterwards. The essential oils of B. tripartita showed a characteristic chemical composition from year to year, observing both quantitative and qualitative compounds differences. The yield of essential oils was 22 and 35 % higher in 2010 year material than in 2009 and 2011 year, respectively. The main compounds found in the B. tripartita essential oils were α-pinene (3.7–12.1 %), p-cymene (2.8–8.0 %), β-ocimene (40.5–45.9 %), β-elemene (9.9–15.6 %), iso and α-caryophyllenes (4.3–6.8 % and 5.2–8.2 %), and α-bergamotene (3.3–9.4 %). To determine the significance of changes in the identified compounds in the samples, representing different plant collection year, statistical hypothesis testing was applied. For classification of these samples to the groups and evaluation of similarity between them principal component analysis, multivariate analysis of variance and hierarchical cluster analysis techniques were used. The correlation analysis helped to find out the strength of linear relationship between amount of each compound and meteorological data (temperature and precipitations).  相似文献   
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