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Franc Strle Lara Lusa Eva Ru?i?-Sablji? Vera Maraspin Stanka Lotri? Furlan Jo?e Cimperman Katarina Ogrinc Tereza Rojko Jerneja Vide?nik Zorman Da?a Stupica 《PloS one》2013,8(12)
Clinical characteristics associated with isolation of Borrelia burgdorferi sensu lato from skin have not been fully evaluated. To gain insight into predictors for a positive EM skin culture, we compared basic demographic, epidemiologic, and clinical data in 608 culture-proven and 501 culture-negative adult patients with solitary EM. A positive Borrelia spp. skin culture was associated with older age, a time interval of >2 days between tick bite and onset of the skin lesion, EM ≥5 cm in diameter, and location of the lesion on the extremities, whereas several other characteristics used as clinical case definition criteria for the diagnosis of EM (such as tick bite at the site of later EM, information on expansion of the skin lesion, central clearing) were not. A patient with a 15-cm EM lesion had almost 3-fold greater odds for a positive skin culture than patients with a 5-cm lesion. Patients with a free time interval between the tick bite and onset of EM had the same probability of a positive skin culture as those who did not recall a tick bite (OR=1.02); however, the two groups had >3-fold greater odds for EM positivity than patients who reported a tick bite with no interval between the bite and onset of the lesion. In conclusion, several yet not all clinical characteristics used in EM case definitions were associated with positive Borrelia spp. skin culture. The findings are limited to European patients with solitary EM caused predominantly by B. afzelii but may not be valid for other situations. 相似文献
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Margaret C. Stanley Helen W. Nathan Lara K. Phillips Sarah J. Knight Josie A. Galbraith Chris J. Winks Darren F. Ward 《Arthropod-Plant Interactions》2013,7(1):59-67
The direct and indirect interactions of invasive ants with plants, insect herbivores, and Hemiptera are complex. While ant and Hemiptera interactions with native plants have been well studied, the effects of invasive ant–scale insect mutualisms on the reproductive output of invasive weeds have not. The study system consisted of Argentine ants (Linepithema humile), boneseed (Chrysanthemoides monilifera monilifera), and sap-sucking scale insects (Hemiptera: Saissetia oleae and Parasaissetia nigra), all of which are invasive in New Zealand. We examined the direct and indirect effects of Argentine ants on scale insects and other invertebrates (especially herbivores) and on plant reproductive output. Argentine ants spent one-third of their time specifically associated with scale insects in tending behaviours. The invertebrate community was significantly different between uninfested and infested plants, with fewer predators and herbivores on ant-infested plants. Herbivore damage was significantly reduced on plants with Argentine ants, but sooty mould colonisation was greater where ants were present. Herbivore damage increased when ants were excluded from plants. Boneseed plants infested with Argentine ants produced significantly more fruits than plants without ants. The increase in reproductive output in the presence of ants may be due to increased pollination as the result of pollinators being forced to relocate frequently to avoid attack by ants, resulting in an increase in pollen transfer and higher fruit/seed set. The consequences of Argentine ant invasion can be varied; not only does their invasion have consequences for maintaining biodiversity, ant invasion may also affect weed and pest management strategies. 相似文献
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Linda M. Penfold Sara Hallager Jeanette Boylan Martine de Wit Lara C. Metrione Marcie Oliva 《Zoo biology》2013,32(1):54-62
To better understand breeding conditions to promote reproduction in captive kori bustards, fundamental endocrine studies measuring fecal androgen metabolites in male and female kori bustards were conducted. Feces collected weekly from males and females were analyzed for testosterone using enzyme‐linked immunoassay. Results from adult males (n = 5), adult females (n = 10), immature males (n = 10), and immature females (n = 10) revealed seasonally elevated testosterone concentrations in fertile, but not nonfertile adult males and females (P > 0.05). Adult females that were not maintained in a breeding group, or that did not produce eggs, did not demonstrate increases in testosterone compared to egg laying counterparts. In males, but not females, seasonal testosterone increases were accompanied by weight gain. Peaks in male fecal androgen metabolites ranged from 10‐ to 22‐fold higher than nonbreeding season (181.5 ± 19.1 vs. 17.0 ± 0.94 ng/g; P < 0.05). Mean breeding season values for adult males were 83.6 ± 6.1 ng/g vs. nonbreeding season values of 12.3 ± 0.73 ng/g (P < 0.05). In females, average breeding season testosterone concentrations were approximately 4‐fold higher than nonbreeding season (55.9 ± 6.0 vs. 14.5 ± 1.8 ng/g), with peaks 10‐ to 30‐fold higher. Results show that noninvasive fecal androgen metabolite analysis can provide a means of predicting fertility potential of male and female kori bustards and might be utilized to assess effects of modifying captive environments to promote reproduction in this species. Zoo Biol. 32:54‐62, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
25.
Thais B. Bittar Yajuan Lin Lara R. Sassano Benjamin J. Wheeler Susan L. Brown William P. Cochlan Zackary I. Johnson 《Journal of phycology》2013,49(3):523-535
Marine phytoplankton have conserved elemental stoichiometry, but there can be significant deviations from this Redfield ratio. Moreover, phytoplankton allocate reduced carbon (C) to different biochemical pools based on nutritional status and light availability, adding complexity to this relationship. This allocation influences physiology, ecology, and biogeochemistry. Here, we present results on the physiological and biochemical properties of two evolutionarily distinct model marine phytoplankton, a diatom (cf. Staurosira sp. Ehrenberg) and a chlorophyte (Chlorella sp. M. Beijerinck) grown under light and nitrogen resource gradients to characterize how carbon is allocated under different energy and substrate conditions. We found that nitrogen (N)‐replete growth rate increased monotonically with light until it reached a threshold intensity (~200 μmol photons · m?2 · s?1). For Chlorella sp., the nitrogen quota (pg · μm?3) was greatest below this threshold, beyond which it was reduced by the effect of N‐stress, while for Staurosira sp. there was no trend. Both species maintained constant maximum quantum yield of photosynthesis (mol C · mol photons?1) over the range of light and N‐gradients studied (although each species used different photophysiological strategies). In both species, C:chl a (g · g?1) increased as a function of light and N‐stress, while C:N (mol · mol?1) and relative neutral lipid:C (rel. lipid · g?1) were most strongly influenced by N‐stress above the threshold light intensity. These results demonstrated that the interaction of substrate (N‐availability) and energy gradients influenced C‐allocation, and that general patterns of biochemical responses may be conserved among phytoplankton; they provided a framework for predicting phytoplankton biochemical composition in ecological, biogeochemical, or biotechnological applications. 相似文献
26.
Anush Kosakyan Fatma Gomaa Edward A.D. Mitchell Thierry J. Heger Enrique Lara 《European journal of protistology》2013,49(2):222-237
Species identification by means of morphology is often problematic in protists. Nebela tincta–collaris–bohemica (Arcellinida) is a species complex of small to medium-sized (ca.100 μm) testate amoebae common in peat bogs and forest soils. The taxonomic validity of characters used to define species within this group is debated and causes confusion in studies of biogeography, and applications in palaeoecology.We examined the relationship between morphological and genetic diversity within this species complex by combined analyses of light microscopy imaging and Cytochrome Oxidase Subunit 1(COI) sequences obtained from the same individual amoeba cells. Our goals were (1) to clarify the taxonomy and the phylogenetic relationships within this group, and (2) to evaluate if individual genotypes corresponded to specific morphotypes and the extent of phenotypic plasticity.We show here that small variations in test morphology that have been often overlooked by traditional taxonomy correspond to distinct haplotypes. We therefore revise the taxonomy of the group. We redefine Nebela tincta (Leidy) Kosakyan et Lara and N. collaris (Ehrenberg 1848) Kosakyan et Gomaa, change N. tincta var. rotunda Penard to N. rotunda (Penard 1890), describe three new species: N. guttata n. sp. Kosakyan et Lara, N. pechorensis n. sp. Kosakyan et Mitchell, and N. aliciae n. sp. Mitchell et Lara. 相似文献
27.
Nagore G. Medina Francisco Lara Vicente Mazimpaka Joaquín Hortal 《Biodiversity and Conservation》2013,22(13-14):3121-3139
Knowledge on the distribution and abundance of species is plagued by significant taxonomic and geographic biases that influence the analyses on biodiversity patterns. Due to this, standard, easy-to-use methods are needed to design efficient field campaigns that minimize data deficiencies. We evaluate the applicability, usefulness and effectiveness of a survey design protocol based on the Environmental Diversity (ED) criterion under different scenarios, with examples of varying extent of environmental niche, range of spatial distribution and level of previous knowledge. We planned surveys for epiphytic bryophytes growing in three types of forests at NW Iberian Peninsula (dominated by Quercus ilex, Q. faginea and Q. pyrenaica). Knowledge on the distribution and abundance of epiphytic bryophytes in this region presents large gaps and strong geographic biases. Besides, the three forest types differ in their environmental requirements, spatial distribution and level of previous knowledge, providing three working scenarios to test the response of the protocol under different situations. The protocol was implemented as a set of sequential selection rules, starting by an ED-based criterion aiming at maximizing the coverage of climatic and geographic variability; further criteria include an iterative set of qualitative properties: maximizing forest area, conservation status and accessibility. The protocol performed efficiently at different ranges of spatial distribution levels of environmental variability, and degree of previous knowledge and generated an even distribution of sampling points that efficiently covered the diversity of epiphytic bryophytes. The results show that ED protocols are a proficient and time-saving approach to select sampling sites by objective criteria also for groups with high dispersal ability and fragmented landscapes. 相似文献
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Tor Paaske Utheim Rakibul Islam Ida G. Fostad Jon R. Eidet Amer Sehic Ole K. Olstad Darlene A. Dartt Edward B. Messelt May Griffith Lara Pasovic 《PloS one》2016,11(3)