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1.
The effect of anti-intercellular adhesion molecule-1 on phorbol-ester-induced rabbit lung inflammation 总被引:24,自引:0,他引:24
R W Barton R Rothlein J Ksiazek C Kennedy 《Journal of immunology (Baltimore, Md. : 1950)》1989,143(4):1278-1282
The role of the CD18 complex of leukocyte glycoproteins in adhesion-dependent functions of human leukocytes in vitro has been well documented. A ligand, intercellular adhesion molecule-1 (ICAM-1), for at least one member of the CD18 complex has been identified. This molecule is inducible on many cell types including vascular endothelium and keratinocytes by inflammatory mediators such as IL-1, TNF, and IFN-gamma. ICAM-1 has been shown to mediate, in part, the in vitro adhesion of lymphocytes and neutrophils to endothelial cells expressing ICAM-1. In the present study we have shown that mAb's to the human CD18 complex and to human ICAM-1 cross react with rabbit cells and that both anti-CD18 and anti-CD11b but neither anti-CD11a nor anti-ICAM-1 mAb's inhibit neutrophil migration, an adhesion-dependent function, in vitro. Pretreatment of rabbits with anti-CD18 and anti-ICAM-1 but not anti-CD11a mAb inhibited by greater than 60% neutrophil migration into PMA-induced inflamed rabbit lungs. This effect of anti-ICAM-1 mAb on pulmonary neutrophil influx after PMA injection has important implications. Specifically, that ICAM-1 can function as a ligand for CD18 and can mediate, at least in part, the migration of neutrophils to inflammatory sites. 相似文献
2.
W Smielak-Korombel I Kulon J Szerszeń-Motyka T Wasik J Ksiazek J Polaczek-Kornecki A Wator-Brzezińska E Ceckiewicz-Swedzio? 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1992,47(40-41):913-915
The fate of young individuals (to 45 years) with a history of myocardial infarction during 12 years was analysed with the aid of a questionnaire containing questions of both social and medical character. Sudden cardiac death or the second infarction were the most frequent causes of death during the first two years following myocardial infarction. Change in the physical activity mainly involved the return to work. Only 47% of young men and 29.8% of women started full-time jobs. They mainly belonged to so-called white collars. The lack of patients' physicians permission was a main cause of the abstinence of young men from the occupation. A position within the family and social activity usually remained unchanged in the majority of patients, but every third patient greatly reduced sexual activity. Every third patients continued smoking, and did not observe recommended diet despite the systematical medical check-ups. The course of the disease is unclear in the majority of young patients. It is often deformed and requires further, detailed information on young patients' style of life. 相似文献
3.
Andrey M. Grishin Eunice Ajamian Linhua Zhang Isabelle Rouiller Mihnea Bostina Miroslaw Cygler 《The Journal of biological chemistry》2012,287(45):37986-37996
Microbial anaerobic and so-called hybrid pathways for degradation of aromatic compounds contain β-oxidation-like steps. These reactions convert the product of the opening of the aromatic ring to common metabolites. The hybrid phenylacetate degradation pathway is encoded in Escherichia coli by the paa operon containing genes for 10 enzymes. Previously, we have analyzed protein-protein interactions among the enzymes catalyzing the initial oxidation steps in the paa pathway (Grishin, A. M., Ajamian, E., Tao, L., Zhang, L., Menard, R., and Cygler, M. (2011) J. Biol. Chem. 286, 10735–10743). Here we report characterization of interactions between the remaining enzymes of this pathway and show another stable complex, PaaFG, an enoyl-CoA hydratase and enoyl-Coa isomerase, both belonging to the crotonase superfamily. These steps are biochemically similar to the well studied fatty acid β-oxidation, which can be catalyzed by individual monofunctional enzymes, multifunctional enzymes comprising several domains, or enzymatic complexes such as the bacterial fatty acid β-oxidation complex. We have determined the structure of the PaaFG complex and determined that although individually PaaF and PaaG are similar to enzymes from the fatty acid β-oxidation pathway, the structure of the complex is dissimilar from bacterial fatty acid β-oxidation complexes. The PaaFG complex has a four-layered structure composed of homotrimeric discs of PaaF and PaaG. The active sites of PaaF and PaaG are adapted to accept the intermediary components of the Paa pathway, different from those of the fatty acid β-oxidation. The association of PaaF and PaaG into a stable complex might serve to speed up the steps of the pathway following the conversion of phenylacetyl-CoA to a toxic and unstable epoxide-CoA by PaaABCE monooxygenase. 相似文献
4.
Dariusz Brzezinski Marcin Kowiel David R. Cooper Marcin Cymborowski Marek Grabowski Alexander Wlodawer Zbigniew Dauter Ivan G. Shabalin Miroslaw Gilski Bernhard Rupp Mariusz Jaskolski Wladek Minor 《Protein science : a publication of the Protein Society》2021,30(1):115-124
The COVID‐19 pandemic has triggered numerous scientific activities aimed at understanding the SARS‐CoV‐2 virus and ultimately developing treatments. Structural biologists have already determined hundreds of experimental X‐ray, cryo‐EM, and NMR structures of proteins and nucleic acids related to this coronavirus, and this number is still growing. To help biomedical researchers, who may not necessarily be experts in structural biology, navigate through the flood of structural models, we have created an online resource, covid19.bioreproducibility.org, that aggregates expert‐verified information about SARS‐CoV‐2‐related macromolecular models. In this article, we describe this web resource along with the suite of tools and methodologies used for assessing the structures presented therein. 相似文献
5.
Beata S. Lipska Irena Balasz-Chmielewska Lucyna Morzuch Kacper Wasielewski Dominika Vetter Halina Borzecka Dorota Drozdz Agnieszka Firszt-Adamczyk Ewa Gacka Tomasz Jarmolinski Joanna Ksiazek Elzbieta Kuzma-Mroczkowska Mieczyslaw Litwin Anna Medynska Magdalena Silska Maria Szczepanska Marcin Tkaczyk Anna Wasilewska Franz Schaefer Aleksandra Zurowska Janusz Limon 《Journal of applied genetics》2013,54(3):327-333
Hereditary nephrotic syndrome is caused by mutations in a number of different genes, the most common being NPHS2. The aim of the study was to identify the spectrum of NPHS2 mutations in Polish patients with the disease. A total of 141 children with steroid-resistant nephrotic syndrome (SRNS) were enrolled in the study. Mutational analysis included the entire coding sequence and intron boundaries of the NPHS2 gene. Restriction fragment length polymorphism (RFLP) and TaqMan genotyping assay were applied to detect selected NPHS2 sequence variants in 575 population-matched controls. Twenty patients (14 %) had homozygous or compound heterozygous NPHS2 mutations, the most frequent being c.1032delT found in 11 children and p.R138Q found in four patients. Carriers of the c.1032delT allele were exclusively found in the Pomeranian (Kashubian) region, suggesting a founder effect origin. The 14 % NPHS2 gene mutation detection rate is similar to that observed in other populations. The heterogeneity of mutations detected in the studied group confirms the requirement of genetic testing the entire NPHS2 coding sequence in Polish patients, with the exception of Kashubs, who should be initially screened for the c.1032delT deletion. 相似文献
6.
Introduction
XbaI single nucleotide polymorphism (SNP) (A/G rs934099) in estrogen receptor 1 gene (ESR1) was described to be associated with curve severity in Japanese idiopathic scoliosis (IS) patients and in Chinese patients with both curve severity and predisposition to IS. PvuII SNP (C/T rs2234693) of ESR1 was described to be associated with the occurrence of IS in the Chinese population; however, two replication studies did not confirm the findings. The ESR1 SNPs have never been studied in Caucasian IS patients.Methods
Case-control study. 287 females with IS underwent clinical, radiological and genetic examinations. The patients were divided into three groups according to curve progression velocity: non-progressive IS, slowly progressive IS (progression <1° per month), and rapidly progressive IS (progression ≥1° per month). The radiological maximum Cobb angle was measured and surgery rate established. A control group consisted of 182 healthy females.Results
All results followed Hardy-Weinberg equilibrium. In the case-control study, genotype frequency in the patients did not differ for the XbaI (AA = 33.5%, AG = 49.1%, GG = 17.4%), nor for the PvuII (TT = 26.8%, TC = 50.2%, CC = 23.0%) comparing to controls (AA = 33.5%, AG = 50.5%, GG = 15.9%) and (TT = 23.1%, TC = 51.1%, CC = 25.8%), respectively, p = 0.3685, p = 0.6046. The haplotype frequency for the patients (AT = 47.1%, GC = 39.2%, AC = 8.9%, GT = 2.8%) did not differ from the controls (AT = 44.8%, GC = 37.4%, AC = 14.0%, GT = 3.8%), p = 0.0645. No difference was found either in XbaI (p = 0.8671) or PvuII (p = 0.3601) allele distribution between the patients and the controls. In the case study, there was no significant difference in genotype frequency for the non-progressive, slowly progressive, and rapidly progressive scoliosis. No difference was found in genotype or haplotype distribution for the mean maximum Cobb angle or the surgery rate.Conclusions
No association was found between ESR1 XbaI or ESR1 PvuII SNP and idiopathic scoliosis in Caucasian females. None of the previously reported associations could be confirmed, regarding curve severity, progression or operation rate. 相似文献7.
8.
The preparation of molecularly imprinted polymers (MIPs) involves the polymerisation of functional monomers in the presence of template molecules. 5,7-Dimethoxycoumarin (DMC) was found to be a structural analogue for aflatoxin B1 (AB1) and serves as its substitute in a grafting solution for the MIP synthesis. It was found that both methacrylic acid and allylamine are functional monomers which could provide a similar binding towards AB1 and DMC. 相似文献
9.
10.
Barbara Pietrzak Anna Bednarska Magdalena Markowska Maciej Rojek Ewa Szymanska Miroslaw Slusarczyk 《Hydrobiologia》2013,715(1):125-134
The combined effect of external environment and energy allocation strategy of the organism on longevity can be exceptional. In a cold oligotrophic fishless habitat, individual Daphnia can live for over a year, several times the usual Daphnia lifespan. This extreme lifespan is in part a consequence of the overwintering strategy which includes storing resources and delaying reproduction until another spring. Yet, contrasting strategies may be applied by Daphnia, resulting in over twofold differences in lifespan within a single habitat. We identify physiological mechanisms mediating such differences in longevity in closely related Daphnia of two lineages coexisting within a high altitude lake, testing the predictions that long-lived animals stay in colder waters and have lower metabolic rates, irrespective of temperature. Vertical distribution of the animals was assessed during three summer stratification seasons, and metabolic activity was measured as oxygen consumption and RNA:DNA ratio. The results not only support our predictions but also reveal that habitat choice is dependent on reproductive status rather than genotype. The young individuals of the overwintering lineage may delay reproduction in part by staying in colder waters than the reproducing adults, which together with low intrinsic metabolic rates may underlie the longevity of Daphnia of this lineage. 相似文献