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排序方式: 共有284条查询结果,搜索用时 15 毫秒
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Marcinkiewicz J Biedroń R Maresz K Kwaśny-Krochin B Bobek M Kontny E Maśliński W Chain B 《Archivum immunologiae et therapiae experimentalis》2004,52(4):284-291
INTRODUCTION: Oxidative modification of proteins affects their biological properties. Previously we have shown that hypochlorite (HOCl), the product of activated neutrophils, enhances protein immunogenecity. Collagen type II, a primary component of cartilage, is commonly used in the induction of arthritis in animals (CIA). The aim of this study was to examine whether HOCl may affect immunogenic, tolerogenic, and arthritogenic properties of collagen. MATERIALS AND METHODS: DBA/J mice were injected with either native (CNAT) or chlorinated collagen (CHOCl) to induce arthritis. The effect of chlorination on collagen properties was measured by evaluation of incidence and severity of CIA. Moreover, the concentration of serum anti-collagen IgG antibodies and myeloperoxidase (MPO) activity in inflamed joints was determined. RESULTS: Mice immunized with CNAT in adjuvant developed arthritis (CIA) with an incidence of 69%. CNAT also exerted tolerogenic properties when injected intravenously either before or shortly after primary immunization, resulting in decreased incidence and severity of CIA, reduced MPO activity in inflamed joints, and lowered serum levels of anti-CNAT IgG anti-bodies. Chlorination of collagen significantly diminished its ability to induce CIA and to trigger generation of anti-CNAT IgG antibodies. Interestingly, chlorination did not affect tolerogenic properties of collagen administered prior to primary immunization with CNAT. CONCLUSIONS: These results suggest that chlorination of collagen may selectively affect functional epitopes of collagen. It is likely that in inflamed joints, neutrophil derived HOCl, in some circumstances, will destroy arthritogenic and immunogenic B cell epitopes, while regulatory T cell epitopes will be preserved. 相似文献
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Wisniewski WM Zagariya AM Pavuluri N Srinivasan H Shankarao S Vidyasagar D 《Pediatric pulmonology》2005,39(4):368-373
Our objective was to study meconium-induced lung injury in isolated perfused rat lungs exposed to anoxia. Our working hypothesis was that meconium-induced lung injury is independent of preexisting hypoxia, and that hypoxia will increase severity of lung injury observed after meconium aspiration. We compared five different groups of animals (n = 5) for pulmonary arterial pressure (PAP), weight lung changes, and TNFalpha expression. Group I had lungs instilled with 4 ml of normal saline. Group II had lungs exposed to 5 min of anoxia. Group III had lungs instilled with 4 ml of 30% filtered human meconium. Group IV had lungs exposed to 5 min of anoxia and then instilled with 4 ml of 30% filtered human meconium. Group V had lungs instilled with 4 ml of 30% unfiltered human meconium. Our subjects were adult Sprague-Dawley rats. The isolated rat lung model was prepared according to Levey and Gast (J Appl Physiol 1966;21:313-316). Lungs were ventilated with room air. Anoxia was caused by the use of N(2). The pulmonary artery was cannulated, and pulmonary arterial pressure and lung weight were measured. Lung weight and pulmonary arterial pressure were monitored for 120 min, and TNFalpha levels were measured in effluent at 15, 30, 60, and 120 min. Experiments were done at the Michael Reese Hospital (Chicago, IL). At the end of the experiment, PAP reached its highest values in group V (10.0 +/- 1.7 mmHg). Final PAPs in groups I-IV were: 4.85 +/- 0.3, 4.99 +/- 0.4, 5.93 +/- 0.3, and 7.25 +/- 0.51 mmHg, respectively). Lung wet weight increased significantly only in groups IV and V vs. group I; at 120 min, they were: 0.96 +/- 0.3 g, P < 0.01, and 1.5 g +/- 0.2 g, P < 0.01, respectively. TNFalpha levels did not change significantly over time in group I. TNFalpha is a marker as well as proprietor of pulmonary inflammatory response. TNFalpha reached its highest levels in groups IV and V: 595 and 753 pg/ml at 120 min, respectively. In conclusion, a short episode of anoxia prior to meconium aspiration may increase lung sensitivity to meconium-induced lung injury. This effect may be moderated by the TNFalpha present in the pulmonary circulation. 相似文献
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Genomic Instability in Pituitary Adenomas 总被引:1,自引:0,他引:1
Pituitary adenomas most commonly are identified as small, incidental microadenomas. They however may progress to macroadenoma forming intra and later suprasellar tumors which in about 1/3 of cases invade surrounding structures at the time of diagnosis. Mechanism of pituitary tumorigenesis remains still elusive. Because the value of karyotyping is limited by the technical problems related to cytogenetic methods, we studied the spectrum of chromosomal imbalances associated with pituitary adenoma using comparative genomic hybridization (CGH). Copy number aberrations on all 22 autosomes were evaluated by CGH using advanced computer software. In total, fifteen patients were included in the study of 9 non-invasive, 4 invasive and two recurrent adenomas. The mean age of the patients were 48 years ranging from 36 to 68 years. Five tumors showed hormonal activity. The histogram of all 15 cases representing the DNA imbalances as an incidence curve along each chromosome showed losses particularly for chromosomes 1p, 2q, 4, 5, 6, 11q, 12q, 13q and 18q as well as overrepresentation on 9q, 16p, 17p, 19, 20q. Functioning adenomas carried more imbalances than non-functioning, specifically deletions on chromosome 4 and 18q as well as overrepresentations of chromosomes 17 and 19. Invasive adenomas carried more overrepresentations at 1p34 than non-invasive tumors. Recurrent adenomas harbored more alterations than primary tumors, particularly DNA gains. The primary data is accessible at our CGH online tumor database at http://amba.charite.de/cgh. Reviewing the existing literature on the genetics of pituitary adenoma and discussing our results in this context, we hope that our study will contribute to the knowledge of this neoplasm. 相似文献
6.
Mielnik P Chwalinska-Sadowska H Wiesik-Szewczyk E Maslinski W Olesinska M 《Rheumatology international》2012,32(3):639-643
Cytokines are implied in polymyositis/dermatomyositis (PM/DM) pathogenesis. Our aim was to evaluate the serum levels of interleukin-15
(IL-15), soluble receptors for IL-2 (sIL-2R) and TNF-alpha type 1 receptor (sTNF-R1) in PM/DM patients and their relation
to disease activity and clinical symptoms. Thirty-eight patients who met definite or probable criteria of Bohan and Peter
for DM/PM were included into the study. Results in patients with active (41 observations) and inactive disease (24 observations)
were compared with control (15 subjects). The median level of IL-15 was 47.6 ± 170 pg/ml in active patients, 25.15 ± 240 pg/ml
in inactive and 28.5 ± 28.89 pg/ml in controls. We demonstrated significant differences between active patients and controls
in levels of IL-15 (0.016, 95%CI 1.39–57.1). The median level of sIL-2R was 314 ± 388, 235.3 ± 269 and 144.3 ± 152.9 pg/ml,
and the median level of sTNF-R1 was 350 ± 388; 294.7 ± 204.7; 209.5 ± 105.9 pg/ml in active, inactive and control subjects,
respectively. There were significantly higher serum levels of these cytokines in active patients than in control subjects
(for sIL-2R P = 0.05, CI95% 0.4–331; and sTNF-R1 P = 0.031, CI95% 15.1–321.5). The interleukin levels did not differ between inactive patients and controls. Elevation of IL-15,
sIL2-R and sTNF-R1 in active patients provides preliminary evidence for the activation of inflammatory response during PM/DM
flares. Further studies may be needed to explain the mechanisms driving these diseases. 相似文献
7.
Kinga Piorecka Jan Kurjata Irena Bak-Sypien Marek Cypryk Urszula Steinke Wlodzimierz A. Stanczyk 《RSC advances》2020,10(26):15579
This paper presents results of spectroscopic (NMR, FTIR, fluorescence), Q-TOF mass spectrometry and Z-potential analyses of interactions between octa(3-aminopropyl)silsesquioxane hydrochloride (POSS-NH2·HCl) and anticancer drug – doxorubicin hydrochloride. These studies aimed at explanation of the enhanced activity of doxorubicin on co-delivery with POSS-NH2. The results point to the formation of active complexes via ionic interactions between the ammonium chloride groups of silsesquioxane and the drug, and not, as suggested earlier, via NH⋯N hydrogen bonding. It has also been shown that the main driving force for the formation of the complexes can be strengthened by π–π stacking and hydrogen bonds. The experimental results are supported by quantum mechanical calculations. This work has proven that co-delivery with POSS offers a potentially advantageous and simple approach for improved efficacy in chemotherapy, avoiding often complicated synthesis of conjugates, involving covalent bonding between drug, nanocarrier and targeting agents.The interaction between polyhedral oligomeric silsesquioxane (POSS) and doxorubicin, leading to formation of active complexes involving POSS functional aminopropyl groups and anthracycline functional groups. 相似文献
8.
Emilio Reyes-Aldrete Erik A. Dill Cecile Bussetta Michal R. Szymanski Geoffrey Diemer Priyank Maindola Mark A. White Wlodzimierz M. Bujalowski Kyung H. Choi Marc C. Morais 《Viruses》2021,13(1)
Double-stranded DNA viruses package their genomes into pre-assembled protein procapsids. This process is driven by macromolecular motors that transiently assemble at a unique vertex of the procapsid and utilize homomeric ring ATPases to couple genome encapsidation to ATP hydrolysis. Here, we describe the biochemical and biophysical characterization of the packaging ATPase from Lactococcus lactis phage asccφ28. Size-exclusion chromatography (SEC), analytical ultracentrifugation (AUC), small angle X-ray scattering (SAXS), and negative stain transmission electron microscopy (TEM) indicate that the ~45 kDa protein formed a 443 kDa cylindrical assembly with a maximum dimension of ~155 Å and radius of gyration of ~54 Å. Together with the dimensions of the crystallographic asymmetric unit from preliminary X-ray diffraction experiments, these results indicate that gp11 forms a decameric D5-symmetric complex consisting of two pentameric rings related by 2-fold symmetry. Additional kinetic analysis shows that recombinantly expressed gp11 has ATPase activity comparable to that of functional ATPase rings assembled on procapsids in other genome packaging systems. Hence, gp11 forms rings in solution that likely reflect the fully assembled ATPases in active virus-bound motor complexes. Whereas ATPase functionality in other double-stranded DNA (dsDNA) phage packaging systems requires assembly on viral capsids, the ability to form functional rings in solution imparts gp11 with significant advantages for high-resolution structural studies and rigorous biophysical/biochemical analysis. 相似文献
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Wlodzimierz Kuroczynski David Senft Amelie Elsaesser Christoph Kampmann 《Archives of Medical Science》2014,10(4):706-710