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81.
Aboul-Enein HY Kladna A Kruk I Lichszteld K Marchlewicz M Michalska T Salem OI Hartmann RW 《Biopolymers》2004,73(5):631-639
4-(4-Phenoxybenzoyl)benzoic acid derivatives (PBADs) were found to inhibit rat and human alpha-reductase isozymes 1 and 2 in vitro. Chemiluminescence (CL), electron spin resonance, spin trapping techniques, and spectrophotometry were used to examine the effect of PBADs on reactive oxygen species (superoxide radical, O(2)(.-); hydroxyl radical, HO(*); singlet oxygen, (1)O(2)) generating systems. All test compounds at a concentration of 0.5 mM enhanced the CL from O(2)(.-) up to fivefold, which was recorded as the light sums during 1 min. At 0.38 mM PBAD enhanced production of HO(*) from H(2)O(2) in the presence of Co(II) up to 90%, as measured by a deoxyribose assay. Using the spin trap agent 5,5-dimethyl-1-pyrroline-N-oxide, it was found that the amplitude of the signal arising from the Fenton-like reaction [Co(II)/H(2)O(2)] was significantly diminished by the test compounds. The compounds also inhibited the (1)O(2) dependent 2,2,6,6-tetramethylpiperidine-N-oxide radical, which is generated in the acetonitrile/H(2)O(2) system. The measured rate constants of (1)O(2)-dimol quenching by PBAD were in the range of (0.8-2.6) x 10(8) M(-1) s(-1). The interaction between PBAD and (1)O(2) was also checked using a spectrophotometry method based on bleaching of p-nitrosodimethylaniline. These results indicate that PBAD may directly scavenge HO(*) and (1)O(2), but not O(2)(.-). However, the compounds that were examined had prooxidant ability under some reaction conditions. 相似文献
82.
83.
Trybek G Kolasa A Marchlewicz M Wenda-Rózewicka L Wiszniewska B 《Reproductive biology》2005,5(3):291-301
Dihydrotestosterone (DHT), 5alpha-reduced metabolite of testosterone, is the most potent androgen in the epididymis. The conversion of T into DHT is carried out by 5alpha-reductase. The activity of 5alpha-reductase type 2, preferentially expressed in the epididymis can be inhibited by a finasteride (a steroid-based specific inhibitor of 5alpha-reductase type 2) which results in DHT deficiency. The aim of the study was to examine the morphology of epididymis and the immunolocalization of an androgen receptor (AR) in the initial segment, caput and cauda epididymis of rats treated with finasteride for 56 days. There were no morphological changes in the morphology of epididymal epithelium in the experimental rats. Immunostainable AR was localized in nuclei of epithelial cells, smooth muscle cells and mainly in the cytoplasm of interstitial cells in the epididymis of control rats. In the epididymis of experimental rats, AR immunostaining was noticed mainly in the cytoplasm of epithelial cells and interstitial cells. The single cells of the initial segment epithelium, basal cells and smooth muscle cells of cauda epididymis showed nuclear AR staining. In conclusion, finasteride affected the expression of the AR in the rat epididymis without changing the morphology of epididymal epithelium. Altered AR expression reflected the hormonal status within the epididymis. 相似文献
84.
Elżbieta Czarniewska Arkadiusz Urbański Szymon Chowański Mariola Kuczer 《Insect Science》2018,25(3):429-438
The subject of this article is a search for the long‐term immunological effects of alloferon and 3 structural analogues of alloferon, which were earlier characterized by the highest pro‐apoptotic activity in Tenebrio molitor. The differences in the actions of these peptides on immune response were observed. Alloferon increased nodulation and significantly phenoloxidase activity in the hemolymph of experimentally infected T. molitor. However, [Phe(p‐NH2)1]‐ and [Phe(p‐OMe)1]‐alloferon strongly inhibited cellular and humoral defense of the mealworm against Staphylococcus aureus infection. One day after injection of these peptides, the specific biochemical and morphological hallmarks of apoptosis in bacteria‐challenged hemocytes were visible; in contrast, 3 days after peptides injection in all hemocytes, caspase activation was not observed. However, these new, circulating hemocytes differed from the control and the peptide‐untreated bacteria‐challenged hemocytes. They had an increased adhesion that led to a separation of viable, anucleated fragments of hemocytes that retain the ability to adhere and to form long filopodia. The peptide‐induced separation of hemocyte fragments may resemble the formation of platelets in mammals and perhaps play a role in sealing wounds in insects. The results of in vivo studies may suggest a long half‐life of studied peptides in the hemolymph of mealworm. Moreover, we showed the importance of the N‐terminal histidine residues at position one of the alloferon molecule for its immunological properties in insects. The results obtained here show that alloferon plays pleiotropic functions in insects. 相似文献
85.
Wojtaszek Przemysław Mariola Piślewska G. Paul Bolwell 《Acta Physiologiae Plantarum》1998,20(3):299-305
Plant species from genus Lupinus are among the oldest known legumes, and various aspects of their biology are considerably different from those commonly observed
within Leguminosae. To study this issue in more detail, a suspension culture of Lupinus albus cells was developed, and the glycosylation patterns of exocellular proteins analysed. N-linked oligosaccharide side-chains
were detected with two lectins: concanavalin A (ConA) and wheat germ agglutinin (WGA) used with respective anti-lectin antibodies,
while O-linked arabinosylated side-chains of (hydroxy)proline-rich glycoproteins were identified with anti-(42 kDa French
bean chitin-binding protein) antibodies. The obtained data were compared with analogous ones for exocellular (glyco)proteins
from suspension-cultured Phaseolus vulgaris cells and from various tissues of L. albus plants. Major species-specific differences between exocellular (glyco)proteins from lupin and bean cells were identified.
Similarly, developmentally regulated glycosylation changes following transition from organised plant tissue to dedifferentiated
suspension-cultured lupin cells were detected and analysed. 相似文献
86.
Human Langerhans cells (LC) were isolated from epidermal cell preparations by panning with mouse anti-CD1 monoclonal antibody. RNA was prepared and probed for the presence of mRNAs for various cytokines using radiolabeled cDNAs. After stimulation with phorbol myristate acetate LC express RNA for interleukin 1α (IL-1α) and interleukin 1β (IL-1β) and produce proteins but do not secrete them at detectable levels. LC-associated IL-1, particularly IL-1α, may play a role in antigen presentation. PMA did not induce IL-6 expression in LC. The addition of lipopolysaccharide, a muramyl dipeptide analog, ionomycin, IL-1α, tumor necrosis factor-α, insulin-like growth factor-1 or IL-6 did not induce IL-1 mRNA in LC. UVB augmented IL-1β mRNA expression. Glucocorticoids did not detectably affect IL-1α or IL-1β mRNA levels following PMA induction, however, staurosporin inhibited IL-1β mRNA synthesis. Thus the inducers and regulators of IL-1 formation in human LC and monocytes are not identical. 相似文献
87.
Bindu Nanduri Leslie A. Shack Aswathy N. Rai William B. Epperson Wes Baumgartner Ty B. Schmidt Mariola J. Edelmann 《Analytical biochemistry》2016
To develop a reproducible tissue lysis method that retains enzyme function for activity-based protein profiling, we compared four different methods to obtain protein extracts from bovine lung tissue: focused ultrasonication, standard sonication, mortar & pestle method, and homogenization combined with standard sonication. Focused ultrasonication and mortar & pestle methods were sufficiently effective for activity-based profiling of deubiquitinases in tissue, and focused ultrasonication also had the fastest processing time. We used focused-ultrasonicator for subsequent activity-based proteomic analysis of deubiquitinases to test the compatibility of this method in sample preparation for activity-based chemical proteomics. 相似文献
88.
Studies on the diversity of gastropod fauna were carried out in ten sinkhole ponds with varied sediments types, which were located in a coal mining area (Silesian Upland, Southern Poland). The water bodies with different bottom types were distinguished by their dissimilar water properties and the total organic matter in the sediment. A total of 11 gastropod species from four families were identified. Eleven species occurred in sinkhole ponds with a coal shale bottom, while in water bodies with sandy sediments nine species were found. The gastropod diversity and abundance were lower in water bodies with sandy sediments compared to the ponds with a coal shale bottom. Canonical correspondence analysis (CCA) showed the important factors that influence the gastropod distribution in the subsidence ponds that were studied. 相似文献
89.
Edelmann MJ Iphöfer A Akutsu M Altun M di Gleria K Kramer HB Fiebiger E Dhe-Paganon S Kessler BM 《The Biochemical journal》2009,418(2):379-390
OTUB (otubain) 1 is a human deubiquitinating enzyme that is implicated in mediating lymphocyte antigen responsiveness, but whose molecular function is generally not well defined. A structural analysis of OTUB1 shows differences in accessibility to the active site and in surface properties of the substrate-binding regions when compared with its close homologue, OTUB2, suggesting variations in regulatory mechanisms and substrate specificity. Biochemical analysis reveals that OTUB1 has a preference for cleaving Lys(48)-linked polyubiquitin chains over Lys(63)-linked polyubiquitin chains, and it is capable of cleaving NEDD8 (neural-precursor-cell-expressed developmentally down-regulated 8), but not SUMO (small ubiquitin-related modifier) 1/2/3 and ISG15 (interferon-stimulated gene 15) conjugates. A functional comparison of OTUB1 and OTUB2 indicated a differential reactivity towards ubiquitin-based active-site probes carrying a vinyl methyl ester, a 2-chloroethyl or a 2-bromoethyl group at the C-terminus. Mutational analysis suggested that a narrow P1' site, as observed in OTUB1, correlates with its ability to preferentially cleave Lys(48)-linked ubiquitin chains. Analysis of cellular interaction partners of OTUB1 by co-immunoprecipitation and MS/MS (tandem mass spectrometry) experiments demonstrated that FUS [fusion involved in t(12;6) in malignant liposarcoma; also known as TLS (translocation in liposarcoma) or CHOP (CCAAT/enhancer-binding protein homologous protein)] and RACK1 [receptor for activated kinase 1; also known as GNB2L1 (guanine-nucleotide-binding protein beta polypeptide 2-like 1)] are part of OTUB1-containing complexes, pointing towards a molecular function of this deubiquitinating enzyme in RNA processing and cell adhesion/morphology. 相似文献
90.
Agnieszka Kolasa Mariola Marchlewicz Rafał Kurzawa Wojciech Głąbowski Grzegorz Trybek Lidia Wenda-Różewicka Barbara Wiszniewska 《Cellular & molecular biology letters》2009,14(3):511-527
In our previous studies, we showed that a finasteride-induced DHT deficiency may cause changes in the morphology of the seminiferous
epithelium without any morphological alteration of the epididymis. In this study, we demonstrated the constitutive immunoexpression
of inducible nitric oxide synthase (iNOS) in the testis and epididymis of Wistar rats treated with finasteride for 28 days
(the duration of two cycles of the seminiferous epithelium) and 56 days (the duration of one spermatogenesis). We noted that
a 56-day finasteride treatment mainly caused a decrease in the level of circulating DHT, as well as a statistically insignificant
decrease in the level of T. The hormone deficiency also led to a change in the iNOS immnoexpression in the testis and epididymis
of the finasteride-treated rats. In vitro, DHT did not modify NO production by the epithelial cells of the caput epididymis even when stimulated with LPS and IFNγ,
but it did give rise to an increase in NO production by the epithelial cells of the cauda epididymis without the stimulation.
DHT did not have a statistically significant influence on estradiol production by cultured, LPS- and IFNγ-stimulated epithelial
cells from the caput and cauda epididymis. In conclusion, our data clearly indicates that a finasterideinduced DHT deficiency
intensifies the constitutive expression of iNOS in most rat testicular and epididymal cells, so it can be expected that the
expression of inducible nitric oxide synthase (iNOS) could be regulated by DHT. On the other hand, the profile of the circulating
DHT and T levels strongly suggests that the regulation of constitutive iNOS expression is complex and needs more detailed
study. 相似文献