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Radosław Juszczak Leszek Kuchar Jacek Leśny Janusz Olejnik 《International journal of biometeorology》2013,57(1):31-44
The main goal of this paper is to estimate how the observed and predicted climate changes may affect the development rates and emergence of the codling moth in the southern part of the Wielkopolska region in Poland. In order to simulate the future climate conditions one of the most frequently used A1B SRES scenarios and two different IPCC climate models (HadCM3 and GISS modelE) are considered. A daily weather generator (WGENK) was used to generate temperature values for present and future climate conditions (time horizons 2020–2040 and 2040–2060). Based on the generated data set, the degree-days values were then calculated and the emergence dates of the codling moth at key stages were estimated basing on the defined thresholds. Our analyses showed that the average air surface temperature in the Wielkopolska region may increase from 2.8°C (according to GISS modelE) even up to 3.3°C (HadCM3) in the period of 2040–2060. With the warming climate conditions the cumulated degree-days values may increase at a rate of about 142 DD per decade when the low temperature threshold (T low ) of 0°C is considered and 91 DD per decade when T low ?=?10°C. The key developmental stages of the codling moth may occur much earlier in the future climate conditions than currently, at a rate of about 3.8–6.8 days per decade, depending on the considered GCM model and the pest developmental stage. The fastest changes may be observed in the emergence dates of 95% of larvae of the second codling moth generation. This could increase the emergence probability of the pest third generation that has not currently occurred in Poland. 相似文献
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Andrea Kucharíková Katarína Kimáková Christian Janfelt Eva Čellárová 《Physiologia plantarum》2016,157(1):2-12
Plants of the genus Hypericum are widely known for their therapeutic properties. The most biologically active compounds of this genus are naphtodianthrones and phloroglucinols. Indirect desorption electrospray ionization mass spectrometry (DESI‐MS) imaging allows visualization and localization of secondary metabolites in different plant tissues. This study is focused on localization of major secondary compounds in the leaves of 17 different in vitro cultured Hypericum species classified in 11 sections. Generally, all identified naphtodianthrones, protohypericin, hypericin, protopseudohypericin and pseudohypericin were co‐localized in the dark glands of eight hypericin producing species at the site of their accumulation. The known phloroglucinols, hyperforin, adhyperforin, hyperfirin and some new phloroglucinols with m/z [M ? H]? 495 and 569 were localized in the translucent and pale cavities within the leaf in the majority of studied species. The comparison of different Hypericum species revealed an interspecific variation in the distribution of the dark and translucent glands corresponding with the localization of hypericins and phloroglucinols. Moreover, similarities in the localization and composition of the phloroglucinols were observed in the species belonging to the same section. Adding to various quantitative studies focused on the detection of secondary metabolites, this work using indirect DESI‐MSI offers additional valuable information about localization of the above‐mentioned compounds. 相似文献
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Synthesis of active Klebsiella aerogenes urease requires four accessory proteins to generate, in a GTP-dependent process, a dinuclear nickel active site with the metal ions bridged by a carbamylated lysine residue. The UreD and UreF accessory proteins form stable complexes with urease apoprotein, comprised of UreA, UreB, and UreC. The sites of protein-protein interactions were explored by using homobifunctional amino group-specific chemical cross-linkers with reactive residues being identified by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) of tryptic peptides. On the basis of studies of the UreABCD complex, UreD is capable of cross-linking with UreB Lys(9), UreB Lys(76), and UreC Lys(401). Furthermore UreD appears to be positioned over UreC Lys(515) according to decreased reactivity of this residue compared with its reactivity in UreD-free apoprotein. Several UreB-UreC and UreC-UreC cross-links also were observed within this complex; e.g. UreB Lys(76) with the UreC amino terminus, UreB Lys(9) with UreC Lys(20), and UreC Lys(515) with UreC Lys(89). These interactions are consistent with the proximate surface locations of these residues observed in the UreABC crystal structure. MALDI-TOF MS analyses of UreABCDF are consistent with a cross-link between the UreF amino terminus and UreB Lys(76). On the basis of an unexpected cross-link between UreB Lys(76) and UreC Lys(382) (distant from each other in the UreABC structure) along with increased side chain reactivities for UreC Lys(515) and Lys(522), UreF is proposed to induce a conformational change within urease that repositions UreB and potentially could increase the accessibility of nickel ions and CO(2) to residues that form the active site. 相似文献
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Fiori A Kucharíková S Govaert G Cammue BP Thevissen K Van Dijck P 《Eukaryotic cell》2012,11(8):1012-1020
The consequences of deprivation of the molecular chaperone Hsp104 in the fungal pathogen Candida albicans were investigated. Mutants lacking HSP104 became hypersusceptible to lethally high temperatures, similarly to the corresponding mutants of Saccharomyces cerevisiae, whereas normal susceptibility was restored upon reintroduction of the gene. By use of a strain whose only copy of HSP104 is an ectopic gene under the control of a tetracycline-regulated promoter, expression of Hsp104 prior to the administration of heat shock could be demonstrated to be sufficient to confer protection from the subsequent temperature increase. This result points to a key role for Hsp104 in orchestrating the cell response to elevated temperatures. Despite their not showing evident growth or morphological defects, biofilm formation by cells lacking HSP104 proved to be defective in two established in vitro models that use polystyrene and polyurethane as the substrates. Biofilms formed by the wild-type and HSP104-reconstituted strains showed patterns of intertwined hyphae in the extracellular matrix. In contrast, biofilm formed by the hsp104Δ/hsp104Δ mutant showed structural defects and appeared patchy and loose. Decreased virulence of the hsp104Δ/hsp104Δ mutant was observed in the Caenorhabditis elegans infection model, in which high in vivo temperature does not play a role. In agreement with the view that stress responses in fungal pathogens may have evolved to provide niche-specific adaptation to environmental conditions, these results provide an indication of a temperature-independent role for Hsp104 in support of Candida albicans virulence, in addition to its key role in governing thermotolerance. 相似文献
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Soňa Kucharíková Patrick Van Dijck Magdaléna Lisalová Helena Bujdáková 《Central European Journal of Biology》2010,5(3):318-323
In the last decade, infections caused by Candida glabrata have become more serious, particularly due to its decreased susceptibility to azole derivatives and its ability to form biofilm.
Here we studied the resistance profile of 42 C. glabrata clinical isolates to different azoles, amphotericin B and echinocandins. This work was also focused on the ability to form
biofilm which plays a role in the development of antifungal resistance. The minimal inhibitory concentration testing to antifungal
agents was performed according to the CLSI (Clinical and Laboratory Standards Institute) M27-A3 protocol. Quantification of
biofilm was done by XTT reduction assay. All C. glabrata clinical isolates were resistant to itraconazole and sixteen also showed resistance to fluconazole. All isolates remained
susceptible to voriconazole. Amphotericin B was efficient in a concentration range of 0.125–1 mg/L. The most effective antifungal
agents were micafungin and caspofungin with the MIC100 values of ≤0.0313–0.125 mg/L. Low concentrations of these agents reduced biofilm formation as well. Our results show that
resistance of different C. glabrata strains is azole specific and therefore a single azole resistance cannot be assumed to indicate general azole resistance.
Echinocandins proved to have very high efficacy against clinical C. glabrata strains including those with ability to form biofilm. 相似文献
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Barbara Kiesewetter Julius Lukas Andreas Kuchar Marius E. Mayerhoefer Berthold Streubel Heimo Lagler Leonhard Müllauer Stefan W?hrer Julia Fischbach Markus Raderer 《PloS one》2014,9(7)
Background
Orbital marginal zone B-cell lymphoma (OAML) constitutes for the most frequent diagnosis in orbital lymphoma. Relatively little data, however, have been reported in larger cohorts of patients staged in a uniform way and no therapy standard exists to date.Material and Methods
We have retrospectively analyzed 60 patients diagnosed and treated at our institution 1999–2012. Median age at diagnosis was 64 years (IQR 51–75) and follow-up time 43 months (IQR 16–92). All patients had undergone uniform extensive staging and histological diagnosis was made by a reference pathologist according to the WHO classification.Results
The majority of patients presented with stage IE (n = 40/60, 67%), three had IIE/IIIE and the remaining 17 stage IVE. Seven patients with IVE had bilateral orbital disease whereas the others showed involvement of further organs. Treatment data were available in 58 patients. Local treatment with radiotherapy (14/58, 24%) or surgery (3/58, 5%) resulted in response in 82% of patients. A total of 26 patients (45%) received systemic treatment with a response rate of 85%. Nine patients received antibiotics as initial therapy; response rate was 38%. Watchful-waiting was the initial approach in 6/58 patients. In total 28/58 patients (48%) progressed and were given further therapy. Median time-to-progression in this cohort was 20 months (IQR 9–39). There was no difference in time-to-progression after first-line therapy between the different therapy arms (p = 0.14). Elevated beta-2-microglobulin, plasmacytic differentiation, autoimmune disorder and site of lymphoma were not associated with a higher risk for progress.Conclusion
Our data underscore the excellent prognosis of OAML irrespective of initial therapy, as there was no significant difference in time-to-progression and response between local or systemic therapy. In the absence of randomized trials, the least toxic individual approach should be chosen for OAML. 相似文献8.
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Stereoselectivity of the pharmacokinetics of the nonsteroidal anti-inflammatory drug flobufen, 4-(2', 4'-difluorobiphenyl-4-yl)-2-methyl-4-oxobutanoic acid, was studied in male Wistar rats after intravenous administration. Pharmacokinetic parameters and chiral inversion of flobufen enantiomers were studied after a bolus injection of the racemate and individual enantiomers (5 mg/kg). Determinations of the enantiomers in rat plasma were performed using chiral HPLC (terguride column). After i.v. administration of flobufen racemate, plasma levels of R-enantiomer decreased more rapidly. The S-/R-enantiomer ratio of AUCs after rac-flobufen was 13.3. The total plasma clearance value of S-flobufen was more than 10-fold lower than R-flobufen. The other pharmacokinetic parameters of the enantiomers were also significantly different. While only traces of R-enantiomer (less than 1%) were detected in rat plasma after S-flobufen administration, considerable conversion to the S-enantiomer was found after injection of R-flobufen (R-enantiomer AUC/S-enantiomer AUC = 0.52). The results indicate substantial stereoselectivity in the disposition of flobufen enantiomers in the rat, which is, at least in part, attributed to chiral bioconversion. 相似文献
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