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61.
Colorado potato beetle (CPB, Leptinotarsa decemlineata Say) (Coleoptera: Chrysomelidae) is one of the most serious insect pest feeding on wild and cultivated Solanaceae plants. This pest poses a significant threat to potato crops. CPB originated from North America but has become widespread and has adapted in new localizations. Currently, it is reported in many countries worldwide. Endosymbiotic bacteria might have an influence on insect adaptation to new conditions. They are known to play a role in invasiveness of insect hosts and to facilitate colonization of new niches; however, information on endosymbionts of the CPB is very limited. In this study, we screened CPB populations collected from 20 evenly distributed locations in Poland for the presence of Arsenophonus, Cardinium, Wolbachia, and Flavobacterium. We found the presence of Flavobacterium in the studied insects. Little is known about CPB–endosymbionts interactions, thus this study may provide a reference for future studies in this subject.  相似文献   
62.
Purpose

The study was conducted to quantify the polycyclic aromatic hydrocarbons (PAHs) accumulation in urban soils from different functional areas via atmospheric inputs with particulate matter.

Materials and methods

PAH concentration and pattern were measured in the particulate matter of snow depositions, in the upper layers of artificial soils from densely built-up areas and in the undisturbed natural soils (Umbric Retisols) from green park area. Samples were collected in 2011–2013 at 58 sites with different traffic activities located at the territory of the Eastern Administrative Okrug of Moscow. The soil samples and filters with particulate matter were extracted by pressurized liquid extraction using Dionex ASE200. Clean-up analyses were performed on SPE cartridges filled with silica gel. Concentrations of PAHs were determined by high-performance liquid chromatography using an Agilent 1100 System equipped with fluorescent detector.

Results and discussion

Mean values of PAH input with snow particles were 45–57 μg/m2 for recreational and residential zones, and 140–264 μg/m2 for traffic zones. The samples of depositions from different functional areas showed a similar PAH pattern and consisted primarily of 3–4-ring PAHs. Total PAH concentrations in upper layers of artificial soils showed similar mean values of 1.43–2.21 μg/g for all functional zones. The PAH content in soils from the park area was twofold lower than that from the built-up area (0.34–0.63 μg/g), despite equal levels of atmosphere contamination on these territories. The upper layers of natural soils from recreational and traffic zones showed slight differences in PAH content, though PAH input with snow was fivefold higher in the traffic zone. Compared with airborne depositions, soils contained significant amounts of 5–6-ring PAHs.

Conclusions

A high level of soil PAH contamination in urban areas of Moscow, several orders of magnitude higher than the current PAH input to them from the atmosphere, indicates a lack of direct connection of the PAH pool in soils with this source. The high PAH content in the upper layer of constructed soils can be the result of repeated use of materials subjected to a constant technogenic impact for the production of artificial soils.

  相似文献   
63.
Near-infrared (NIR) spectroscopy and partial least-square regression were used for determination of alpha-tocopherol in edible oils after extraction with ethanol. The standard error of calibration and the standard error of prediction were calculated for evaluation of the calibration models. The chemometric calibration model was prepared in spectral region 6500-4500 cm(-1) for standard alpha-tocopherol solutions (0.54-53.54 mg/mL). Obtained mean concentrations of natural alpha-tocopherol in different types of oils varied from 17.53 to 57.10 mg/100 g. Net analyte signal calculation was used to estimate detection limit (DL = 0.12 mg/mL), quantification limit (QL = 0.40 mg/mL), sensitivity (SEN = 0.045 mg/mL), and selectivity (SEL ranged between 0.24 and 0.54% of the measured reflectance signal) of the proposed NIR method. The comparable precision (RSD = 0.68-2.80% and 0.79-3.06%) and accuracy (recovery, 97.2-102.4% and 96.8-103.2%) for the proposed NIR and standard HPLC methods, demonstrate the benefit of the NIR method in the routine analysis of alpha-tocopherol in vegetable oils.  相似文献   
64.
Yeast cell wall invertase (CWI) was modified with dimethyl suberimidate, glutaraldehyde, formaldehyde, and sodium periodate. Retained activity after modification was 45% for CWI modified with formaldehyde, 77% for CWI modified with sodium periodate, 80% for CWI modified with glutaraldehyde, and 115% for CWI modified with dimethyl suberimidate. Chemically modified and native CWIs showed significantly broad pH stability (pH 3-11), whereas after incubations at 50, 60, and 70 °C, CWI modified with glutaraldehyde showed the highest thermostability. Optimum pH for CWI modified with glutaraldehyde was between 4 and 5, whereas optimum temperature was at 60 °C. Comparison to CWI modified with glutaraldehyde after immobilization within alginate beads showed broader pH optimum (4.0-5.5) as well as broader temperature optimum (55-70 °C). Column bed reactor packed with the immobilized CWI modified with glutaraldehyde was successfully used for the 95% inversion of 60% (w/w) sucrose at the flow rate of 3 bed volumes per hour, pH 4.9, and 45 °C. A 1 month productivity of 3844 kg of inverted sugar/kg of the immobilisate was obtained.  相似文献   
65.
Codium bernabei is a green alga that grows on Chilean coasts. The composition of its structural polysaccharides is still unknown. Hence, the aim of this work is to isolate and characterize the hot water extracted polysaccharide fractions. For this purpose, the water extracts were further precipitated in alcohol (TPs) and acid media (APs), respectively. Both fractions were characterized using different physicochemical techniques such as GC-MS, GPC, FTIR, TGA, and SEM. It is confirmed that the extracted fractions are mainly made of sulfated galactan unit, with a degree of sulfation of 19.3% (TPs) and 17.4% (ATs) and a protein content of 3.5% in APs and 15.6% in TPs. Other neutral sugars such as xylose, glucose, galactose, fucose, mannose, and arabinose were found in a molar ratio (0.05:0.6:1.0:0.02:0.14:0.11) for TPs and (0.05:0.31:1.0:0.03:0.1:0.13) for ATs. The molecular weight of the polysaccharide samples was lower than 20 kDa. Both polysaccharides were thermally stable (Tonset > 190 °C) and showed antioxidant activity according to the ABTS•+ and DPPH tests, where TPs fractions had higher scavenging activity (35%) compared to the APs fractions. The PT and APTTS assays were used to measure the anticoagulant activity of the polysaccharide fractions. In general, the PT activity of the TPs and APs was not different from normal plasma values. The exception was the TPs treatment at 1000 µg mL−1 concentration. The APTTS test revealed that clotting time for both polysaccharides was prolonged regarding normal values at 1000 µg mL−1. Finally, the antitumor test in colorectal carcinoma (HTC-116) cell line, breast cancer (MCF-7) and human leukemia (HL-60) cell lines showed the cytotoxic effect of TPs and APs. Those results suggest the potential biotechnological application of sulfate galactan polysaccharides isolated from a Chilean marine resource.  相似文献   
66.
Polycystic kidney disease (PKD) is an inherited autosomal kidney disease which is most commonly identified in Persian and Persian related cats. Positive cats have multiple cysts of various sizes that occur in the renal cortex and medulla and occasionally in other abdominal organs. PKD often leads to renal failure which occurs from mid to late in life. Renal cysts can be diagnosed ultrasonographically after 7 weeks of age by an experienced ultrasonographer and a high resolution machine. However, ultrasonography is now being replaced by genetic screening. A total of 340 cats of variable breeds aged from 5 months to 18 years were ultrasonographically examined in the past 7 years at the University Veterinary Small Animal Clinic. Of these, 13.8% were PKD positive with very high prevalence in Persian cats (36%). There was no sex predilection identified. The C>A transversion at position 3284 on exon 29 of PKD1 gene, resulting in a stop mutation has been identified in the heterozygous state in eight affected cats examined (Persian breed). All heterozygous cats were also ultrasonographically positive.  相似文献   
67.
We estimated that more than 11,000 people were exposed to highly pathogenic avian influenza viruses in EU/EEA countries over the outbreak period October 2016–September 2018 by cross‐linking data submitted by Member States to European Food Safety Authority and EMPRES‐i. A stronger framework for collecting human exposure data is required.  相似文献   
68.
During the last few years, the number of cases of Trichophyton verrucosum isolation from humans suffering from mycoses has been constantly increasing, which is correlated with the presence of an increasing number of outdoor breeding farms. Farmers and their families as well as veterinarians and technicians involved in handling the animals are at a higher risk of infection. One of the most important aims of mycological diagnostics is epidemiological analysis. Typically, the history of the disease is not sufficient to indicate reliably and eliminate the outbreak of infection. PCR fingerprinting methods are a useful tool in this type of analysis, which is presented in this study. The main aim is to present diagnostic and epidemiological analyses of dermatophyte isolates from llamas and their breeder. In two llamas, round alopecia sites or ca. 2‐cm excoriations covered with thickened scaling epidermis were noticed at the border of the head and neck with a distinct tendency towards hair loss. Tinea unguium was noticed in a nail of the breeder's right hand. Direct analysis of the material from the clinical lesions revealed the presence of arthrospores. The macro‐ and micromorphology of the isolates were homogeneous and characteristic for T. verrucosum. The identification analysis based on the ITS sequences confirmed the previous morphological diagnostic examination. The MP‐PCR and MSP‐PCR analysis indicated high invariability of the genomes of the strains isolated from the human and animals. The epidemiological research has indicated an identical source of dermatophyte infection in the breeder and the lamas. To sum up, the number of pets and farm animals is increasing and dermatologists should always be informed about possible dermatophyte transmission sources. The possibility of transmission of zoophilic dermatophytes from humans to animals is a suggestion for further analysis; therefore, this type of transmission should be considered in dermatological studies.  相似文献   
69.
The anticancer activity of novel platinum derivative, a complex of platinum with tris(2‐carboxyethyl)phosphine (Pt‐TCEP), has been evaluated in canine (D‐17) and human osteosarcoma (U2‐OS) cell lines. Viability of cells after incubation for 24 or 72 hours with increasing concentrations (0.625, 1.25, 2.50, 5, 10 and 20 μM) of Pt‐TCEP was tested in an MTT assay and compared to effect of cisplatin. Longer‐term effect of Pt‐TCEP was evaluated in the colony‐forming unit assay after 24 hours exposure to the Pt‐TCEP (2 and 3 μM) and subsequent incubation for 2 weeks. The influence of the compound on the cell cycle was measured after 24 hours treatment with Pt‐TCEP (3 μM). Its pro‐apoptotic activity was examined after 24 hours treatment with Pt‐TCEP (1.25, 2.50, 5, 10 and 20 μM) using flow cytometry. Expression of main proteins involved in apoptosis was measured after exposure for 24 hours to 3 or 5 μM Pt‐TCEP in Western Blot. The compound much more effectively decreased cell viability than cisplatin in case of both cell lines. IC50 of Pt‐TCEP was 5.93 ± 0.12 in D‐17 and 3.45 ± 0.14 in U2‐OS cell lines after 24 hours, and 1.77 ± 0.14 in D‐17 and 1.53 ± 0.11 in U2‐OS after 72 hours (P < .05). The compound arrested cells in the G2/M phase and inhibited the ability of cells to form colonies. Pt‐TCEP induced caspase‐dependent apoptosis. The expression of the anti‐apoptotic Bcl‐XL protein was decreased after Pt‐TCEP treatment in both cell lines. The results confirmed anti‐cancer activity of Pt‐TCEP against canine and human osteosarcoma cell lines.  相似文献   
70.
The poor physical, chemical and biological properties make Stagnic Luvisol highly susceptible to water erosion on sloping terrains. The objective of this paper is to estimate the effect of different tillage treatments and crops (maize, soybean, winter wheat, spring barley, oilseed rape) on water erosion. The highest erosion in investigation period (1995–2014) was recorded in the control treatment with fallow, followed by the treatment that involved ploughing and sowing up and down the slope. Significantly, lower soil losses were recorded in no-tillage and treatments with ploughing and sowing across the slope. Regarding the crops significantly higher soil losses were recorded in spring row crops (maize and soybean) compared to high-density winter crops (wheat and oilseed rape) and double crop (spring barley with soybean). In the studied period, an average loss of 46 mm of the plough layer was recorded in the control treatment, while in treatment with ploughing and sowing up and down the slope average annual soil loss was 10 mm. According to the results of this study no-tillage and tillage across the slope are recommended as tillage which preserves soil for the next generations in agro-ecological conditions of continental Croatia.  相似文献   
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