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91.
Lydka M Kopera-Sobota I Kotula-Balak M Chojnacka K Zak D Bilinska B 《Acta veterinaria Scandinavica》2011,53(1):12
Background
The dynamic cross-talk between epididymal cells is hormonally regulated and, in part, through direct cell-to-cell interactions. To date, no information is available regarding possible impact of anti-androgens on the proteins involved in the gap junctional communication within the boar epididymis. Thus, a question arised whether prenatal or postnatal exposure to an anti-androgen flutamide alters the expression of gap junction protein - connexin43 (Cx43) and androgen receptor (AR) expression in the caput, corpus and cauda epididymis and leads to delayed effects on morphology and function of adult pig epididymis.Methods
First two experimental groups received flutamide prenatally on gestational days 20-28 and 80-88 (GD20 and GD80) and further two groups were exposed to flutamide postanatally on days 2-10 and 90-98 after birth (PD2 and PD90). Epididymides were collected from adult boars. Routine histology was performed using hematoxylin-eosin staining. The expression of Cx43 and AR were analyzed using immunohistochemistry and Western blotting. Both analyses were supported by quantitative approaches to demonstrate the variations of the expression levels following the treatment. Apoptotic cells were identified using TUNEL assay.Results
Histological examination revealed differences in epididymal morphology of flutamide-exposed boars when compared to controls. Scarce spermatic content were seen within the corpus and cauda lumina of GD20, PD2 and PD90 groups. Concomitantly, frequency of epididymal cell apoptosis was significantly higher (p < 0.05) after exposure to flutamide at GD20. Moreover, in GD20, PD2, and PD90 groups, significantly lower AR expression (p < 0.05) was found in the principal and basal cells of the corpus and cauda regions, while in the stromal cells AR expression was significantly reduced (p < 0.05) along the epididymal duct. Concomitantly, a decrease in Cx43 expression (p < 0.05) was noticed in the stromal cells of the cauda region of GD20 and PD2 groups. This indicates high sensitivity of the stromal cells to androgen withdrawal.Conclusions
The region-specific alterations in the epididymis morphology and scarce spermatic content within the lumina of the corpus and cauda indicate that flutamide can induce delayed effects on the epididymal function of the adult boar by decrease in AR protein levels that results in altered androgen signaling. This may cause disturbances in androgen-dependent processes including Cx43 (de)regulation, however, we can not exclude the possibility that in response to flutamide decreased Cx43 expression may represent one mechanism responsible for functional disturbance of the boar epididymis. 相似文献92.
Pomorska-Mól M Markowska-Daniel I Kwit K Stępniewska K Pejsak Z 《Veterinary microbiology》2011,152(3-4):429-435
In the present study, acute phase proteins (APP) responses in pigs after infection with toxigenic strain of Pasteurella multocida (Pm) were evaluated. Twelve piglets from a herd free from toxigenic Pm were used. Six of them were infected intranasally with Pm. CRP, Hp, SAA and Pig-MAP concentrations were measured using commercial ELISA tests. CRP and Hp were significantly induced from 2 days post inoculation (dpi). The concentration of Hp in inoculated pigs remained elevated until the end of the study. The concentrations of SAA and Pig-MAP increased significantly from 3 dpi, and remained elevated to 5 or 7 dpi, respectively. Strong correlations were observed between concentration of Hp or SAA and changes in the lungs. No correlations were found between levels of APP in serum and changes observed in the turbinates. On the basis of our investigation, we cannot state that evaluation of APP concentrations in serum may provide useful information about severity of atrophic rhinitis. However, the concentration of all investigated APP increased after inoculation. Thus, APP-measurements may reveal ongoing infection. Monitoring of APP concentrations in the pig herds may help to pinpoint infected animals even before clinical signs are present. If found, these "APP-high" animals may be chosen next for pathogen-specific diagnostics. Early diagnosis and therapy may prevent the infection from spreading in the herd. Moreover, monitoring of APP concentrations in serum may be useful for selecting clinically healthy pigs before integration into an uninfected herd. Future studies should focus on the possibility of distinguishing infected and non-infected pigs under field conditions. 相似文献
93.
We investigated sediments from 23 lakes situated in northeastern Poland and analyzed them for major constituents and selected heavy metals. Short sediment cores were collected from the deepest parts of the lakes, and subsequently, a surface layer (0-2?cm) and reference layer (50-52?cm) were sampled from each. In the collected samples, the content of the major constituents (organic matter, carbonates, and minerogenic material) and chosen heavy metals (Cd, Cu, Ni, Pb, and Zn) was analyzed. In the reference layer, representing natural metal content, we identified quite a substantial diversity among lakes, making it difficult to pinpoint one geochemical background value for the whole region. A multivariate analysis of the interrelationships among elements and a comparison of the median values revealed no statistically significant differences between surface and reference levels. The ratio of the mean content in the surface and reference sediments ranged from 0.9 to 1.6, indicating the lack of or only slight anthropogenic pollution in surface sediments. From a spatial perspective, higher metal contents were observed in the eastern part of the study area, but this trend manifested in both surface and reference sediments. Thus, the inference is that the recently accumulated sediments are characterized by a content that is representative of the natural geochemical background for the selected metals. 相似文献
94.
Gorinstein S Leontowicz H Leontowicz M Najman K Bielecki W Ham KS Kang SG Paredes-Lopez O Martinez-Ayala AL Trakhtenberg S 《Journal of agricultural and food chemistry》2011,59(13):7441-7451
The aim of this investigation was to compare the liver and aorta changes in rats fed cholesterol-containing diets and the possible improvement when diets would be supplemented with frequently used raw vegetables. The phenolic compounds of three vegetables in methanol-water (1:1) fraction were characterized using electrospray ionization mass spectra (ESI-MS). Results showed that the content of polyphenols, flavonoids, quercetin, flavanols, tannins, and ascorbic acid varied for garlic and white and red onions ranging from 6.68 to 18.08 mg GAE/g DW, 490.4-701.0 μg CE/g DW, 281.2-1100.0 μg, 32.40-41.30 μg CE/g DW, 2.88-3.12 mg CE/g DW, 1.87-2.33 mg AA/g DW, 1388.2-1442.3 μg CGE/g DW, respectively. The radical scavenging capacities (μM TE/g DW) for the same investigated vegetables for ABTS, FRAP, CUPRAC, and DPPH assays ranged from 48.78 to 92.42, 9.41-28.56, 3.06-10.41, and 6.49-23.42, respectively. Good correlations were observed between the phenolic contents and the radical scavenging capacities of the vegetables. The interaction between BSA and quercetin, BSA and garlic and onions extracts was measured by 3-dimensional fluorescence (3D-FL) and Fourier transform infrared (FT-IR) spectroscopy. The highest polyphenol content was found in methanol/water fraction of onions and garlic; therefore, for the investigation of in vitro interactions with BSA only polyphenols of this fraction were used. For in vivo studies, 30 male Wistar rats were divided into 5 groups each of 6 and named Control, Chol, Chol/Garlic, Chol/OnionRed, and Chol/OnionWhite. During 6 weeks, the rats of all 5 groups were fed a basal diet (BD). The rats of the Control group were fed the BD only. The BD of the Chol group was supplemented with 10 g/kg of nonoxidized cholesterol (NOC). Each of the other three groups was supplemented with 10 g/kg of NOC and 500 mg of raw fresh garlic, 500 mg of raw fresh red onion, and 500 mg of raw fresh white onion on 1 kg of body weight for Chol/Garlic, Chol/OnionRed, and Chol/OnionWhite diet groups, respectively. In order to detect the changes in the liver and aorta, a histological procedure was applied, and the liver enzymes were determined and compared. It was found that the main changes vs the Control group were in the liver of rats fed the cholesterol-containing diet without vegetable supplementation. Significantly less histological changes in the liver and lower level of liver enzymes vs those of the Chol group were detected in rats of the Chol/Garlic group (P < 0.05). The interaction between the polyphenol extract of garlic and BSA in vitro showed its strong ability comparable with that of quercetin to quench the intrinsic fluorescence of BSA. In conclusion, all studied vegetables showed protective effects, but raw garlic supplemented with cholesterol-containing diets significantly prevented the aorta and liver damages of rats. 相似文献
95.
Marcin Wysokowski ?ukasz Klapiszewski Dariusz Moszyński Przemys?aw Bartczak Tomasz Szatkowski Izabela Majchrzak Katarzyna Siwińska-Stefańska Vasilii V. Bazhenov Teofil Jesionowski 《Marine drugs》2014,12(4):2245-2268
Novel, functional materials based on chitin of marine origin and lignin were prepared. The synthesized materials were subjected to physicochemical, dispersive-morphological and electrokinetic analysis. The results confirm the effectiveness of the proposed method of synthesis of functional chitin/lignin materials. Mechanism of chitin modification by lignin is based on formation of hydrogen bonds between chitin and lignin. Additionally, the chitin/lignin materials were studied from the perspective of waste water treatment. The synthetic method presented in this work shows an attractive and facile route for producing low-cost chitin/lignin biosorbents with high efficiency of nickel and cadmium adsorption (88.0% and 98.4%, respectively). The discovery of this facile method of synthesis of functional chitin/lignin materials will also have a significant impact on the problematic issue of the utilization of chitinous waste from the seafood industry, as well as lignin by-products from the pulp and paper industry. 相似文献
96.
Masternak Katarzyna Oko Sylwia Kamola Marek Ociepa Tomasz Nucia Aleksandra Kowalczyk Krzysztof 《European Journal of Forest Research》2022,141(4):617-628
European Journal of Forest Research - Increasing areas of gradation, making it difficult or impossible to perform restorations and forestations, and as causing tree crown damage, result in the need... 相似文献
97.
Karsak M Gaffal E Date R Wang-Eckhardt L Rehnelt J Petrosino S Starowicz K Steuder R Schlicker E Cravatt B Mechoulam R Buettner R Werner S Di Marzo V Tüting T Zimmer A 《Science (New York, N.Y.)》2007,316(5830):1494-1497
Allergic contact dermatitis affects about 5% of men and 11% of women in industrialized countries and is one of the leading causes for occupational diseases. In an animal model for cutaneous contact hypersensitivity, we show that mice lacking both known cannabinoid receptors display exacerbated allergic inflammation. In contrast, fatty acid amide hydrolase-deficient mice, which have increased levels of the endocannabinoid anandamide, displayed reduced allergic responses in the skin. Cannabinoid receptor antagonists exacerbated allergic inflammation, whereas receptor agonists attenuated inflammation. These results demonstrate a protective role of the endocannabinoid system in contact allergy in the skin and suggest a target for therapeutic intervention. 相似文献
98.
Foss Kamil Przybyłowicz Katarzyna E. Sawicki Tomasz 《Plant foods for human nutrition (Dordrecht, Netherlands)》2022,77(3):383-389
Plant Foods for Human Nutrition - Herbs are characterized by a high content of biologically active substances that positively affect human health. Phenolic compounds are one of the main bioactive... 相似文献
99.
Szewczuk-Karpisz Katarzyna Tomczyk Agnieszka Grygorczuk-Płaneta Katarzyna Naveed Sadiq 《Journal of Soils and Sediments》2022,22(10):2620-2639
Journal of Soils and Sediments - Industrialization and application of large amount of fertilizers together with animal wastes increased pollution of environment with antibiotics and heavy metals.... 相似文献
100.
Jean Bernard Diatta Witold Grzebisz Katarzyna Wiatrowska 《Soil Science and Plant Nutrition》2013,59(6):899-908
Abstract The simultaneous incorporation of heavy metals into the soil is still a matter of great concern. Interaction (competitive sorption) between these metals and the soil solid phase may result in a deterioration of soil quality which relies basically on amounts of alkaline cations saturating soils sorptive complex. Results of this study indicate that Pb, Cu, C d, and Zn have induced solution pH decreases which were more intensive at highest metal loading rates. Partition parameters (Kd)-based sequences showed that Pb and Cu were more competitive than Cd and Zn and the overall selectivity sequence followed: Pb > Cu > Cd > Zn. Metal loadings and their competitive sorption have led to a strengthened displacement of alkaline cations (i.e. Ca2+, Mg2+, K+, Na+), especially of Ca2+ as a factor “stabilizing” soil sorptive complex. Such metals impact jointly with soils acidification are of great environmental concern since tremendous amounts of alkaline cations (especially Ca2+) may be potentially leached out, irrespective of the degree of soil contamination, as evidenced in the current study. High and positive ΔG values implied that the studied soils were characterized by generally low concentrations of exchangeable potassium which required high energy to get displaced (desorbed). Further studies on heavy metal uncontaminated or contaminated areas should be undertaken to provide with data which should be used for predictions on changes related to soil buffering capacity as impacted by heavy metal inputs. 相似文献