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1.
W Bal H Kozlowski E Masiukiewicz B Rzeszotarska I Sóvágó 《Journal of inorganic biochemistry》1989,37(2):135-139
Luteinizing hormone-releasing hormone (LHRH), a hypothalamic neurohormone, forms a complex with Zn ions in solution. In order to explain the structure of this complex, the stability constants of Zn(II) complexes of LHRH and also pyroglutamyl-histidine-methylester, N-acetyl-histamine, and N-acetyl-histidine were established with the use of potentiometric technique. The nuclear magnetic resonance spectroscopy shows that the mode of coordination of Zn(II) to LHRH consists of binding to the imidazole nitrogen and the peptide oxygen of the His-Trp bond. 相似文献
2.
Lyndsey R. Buckner Angela M. Amedee Hannah L. Albritton Pamela A. Kozlowski Nedra Lacour Chris L. McGowin Danny J. Schust Alison J. Quayle 《PloS one》2016,11(1)
Chlamydia trachomatis causes a predominantly asymptomatic, but generally inflammatory, genital infection that is associated with an increased risk for HIV acquisition. Endocervical epithelial cells provide the major niche for this obligate intracellular bacterium in women, and the endocervix is also a tissue in which HIV transmission can occur. The mechanism by which CT infection enhances HIV susceptibility at this site, however, is not well understood. Utilizing the A2EN immortalized endocervical epithelial cell line grown on cell culture inserts, we evaluated the direct role that CT-infected epithelial cells play in facilitating HIV transmission events. We determined that CT infection significantly enhanced the apical-to-basolateral migration of cell-associated, but not cell-free, HIVBaL, a CCR5-tropic strain of virus, across the endocervical epithelial barrier. We also established that basolateral supernatants from CT-infected A2EN cells significantly enhanced HIV replication in peripheral mononuclear cells and a CCR5+ T cell line. These results suggest that CT infection of endocervical epithelial cells could facilitate both HIV crossing the mucosal barrier and subsequent infection or replication in underlying target cells. Our studies provide a mechanism by which this common STI could potentially promote the establishment of founder virus populations and the maintenance of local HIV reservoirs in the endocervix. Development of an HIV/STI co-infection model also provides a tool to further explore the role of other sexually transmitted infections in enhancing HIV acquisition. 相似文献
3.
The ERH gene encodes a highly conserved small nuclear protein with a unique amino acid sequence and three-dimensional structure but unknown function. The gene is present in animals, plants, and protists but to date has only been found in few fungi. Here we report that ERH homologs are also present in all four species from the genus Schizosaccharomyces, S. pombe, S. octosporus, S. cryophilus, and S. japonicus, which, however, are an exception in this respect among Ascomycota and Basidiomycota. The ERH protein sequence is moderately conserved within the genus (58% identity between S. pombe and S.
japonicus), but the intron-rich genes have almost identical intron-exon organizations in all four species. In S. pombe, erh1+ is expressed at a roughly constant level during vegetative growth and adaptation to unfavorable conditions such as nutrient limitation and hyperosmotic stress caused by sorbitol. Erh1p localizes preferentially to the nucleus with the exception of the nucleolus, but is also present in the cytoplasm. Cells lacking erh1+ have an aberrant cell morphology and a comma-like shape when cultured to the stationary phase, and exhibit a delayed recovery from this phase followed by slower growth. Loss of erh1+ in an auxotrophic background results in enhanced arrest in the G1 phase following nutritional stress, and also leads to hypersensitivity to agents inducing hyperosmotic stress (sorbitol), inhibiting DNA replication (hydroxyurea), and destabilizing the plasma membrane (SDS); this hypersensitivity can be abolished by expression of S. pombe erh1+ and, to a lesser extent, S. japonicus erh1+ or human ERH. Erh1p fails to interact with the human Ciz1 and PDIP46/SKAR proteins, known molecular partners of human ERH. Our data suggest that in Schizosaccharomyces sp. erh1+ is non-essential for normal growth and Erh1p could play a role in response to adverse environmental conditions and in cell cycle regulation. 相似文献
4.
5.
Maciej Kempa Szymon Budrejko Marta Piepiorka-Broniecka Jan Rogowski Dariusz Kozlowski Grzegorz Raczak 《PloS one》2015,10(12)
Introduction
The number of pacemaker and ICD implantations has increased substantially in the recent years. Therefore, complications are also observed in a greater number. In many cases, transvenous extraction of the previously implanted device (pacemaker or ICD) is the only solution. One may find in the literature information about the efficacy and safety of that procedure, but data concerning the results of long-term follow up are still limited.Aim
The aim of the study was to assess the one-year mortality in the cohort of patients undergoing transvenous lead extraction procedures in our centre.Methods
Records of the patients undergoing transvenous lead removal in the Department of Cardiology and Electrotherapy of the Medical University of Gdańsk were analyzed. We collected detailed information about 192 patients that had undergone the procedure from January 2003 until June 2012. Data were collected from medical and surgical records. We analyzed concomitant diseases, indications, and possible complications. Long-term follow-up data were gathered in the follow-up ambulatory records and over-the-phone interviews with patients or families. In several cases, we consulted the database of the Polish National Health Fund.Results
During the early post-operative period 5 patients died, although none of those deaths was associated with the procedure itself. No other major complications were observed. During one-year follow-up other 5 patients died, which gave the overall one-year survival rate of 92.7%. Heart failure, renal failure and an infective indication showed significant association with increased mortality.Conclusion
Results of transvenous lead extraction, a relatively safe procedure, should be assessed over time extending beyond the sole perioperative period. Some complications may be delayed in their nature, and may be observed only during the long-term follow up. 相似文献6.
Xiaoyu Yu Dandan Zhang Bisheng Shi Guangxu Ren Xiuhua Peng Zhong Fang Maya Kozlowski Xiaohui Zhou Xiaonan Zhang Min Wu Cong Wang Zhenghong Yuan 《PloS one》2015,10(4)
Hepatitis B virus (HBV) persistent infection is associated with ineffective immune response for the clearance of virus. Immunomodulators represent an important class of therapeutics, which potentially could be beneficial for the treatment of HBV infection. The particulate yeast-derived glucan (PYDG) has been shown to enhance the innate and adaptive immune responses. We therefore, assessed the efficacy of PYDG in enhancing HBV specific immune responses by employing the hydrodynamic injection-based (HDI) HBV transfection mouse model. Mice were intragatric administered PYDG daily for 9 weeks post pAAV/HBV1.2 hydrodynamic injection. PYDG treatment significantly promoted HBV DNA clearance and production of HBsAb compared to control mice. PYDG treatment resulted in recruitment of macrophages, dendritic cells (DCs) and effector T cells to the liver microenvironment, accompanied by a significantly augmented DCs maturation and HBV-specific IFN-γ and TNF-α production by T cell. In addition, enhanced production of Th1 cytokines in liver tissue interstitial fluid (TIF) was associated with PYDG administration. Live imaging showed the accumulation of PYDG in the mouse liver. Our results demonstrate that PYDG treatment significantly enhances HBV-specific Th1 immune responses, accompanied by clearance of HBV DNA, and therefore holds promise for further development of therapeutics against chronic hepatitis B. 相似文献
7.
Radoslaw Charkiewicz Jacek Niklinski Jürgen Claesen Anetta Sulewska Miroslaw Kozlowski Anna Michalska-Falkowska Joanna Reszec Marcin Moniuszko Wojciech Naumnik Wieslawa Niklinska 《Translational oncology》2017,10(3):450-458
Advances in molecular analyses based on high-throughput technologies can contribute to a more accurate classification of non–small cell lung cancer (NSCLC), as well as a better prediction of both the disease course and the efficacy of targeted therapies. Here we set out to analyze whether global gene expression profiling performed in a group of early-stage NSCLC patients can contribute to classifying tumor subtypes and predicting the disease prognosis. Gene expression profiling was performed with the use of the microarray technology in a training set of 108 NSCLC samples. Subsequently, the recorded findings were validated further in an independent cohort of 44 samples. We demonstrated that the specific gene patterns differed significantly between lung adenocarcinoma (AC) and squamous cell lung carcinoma (SCC) samples. Furthermore, we developed and validated a novel 53-gene signature distinguishing SCC from AC with 93% accuracy. Evaluation of the classifier performance in the validation set showed that our predictor classified the AC patients with 100% sensitivity and 88% specificity. We revealed that gene expression patterns observed in the early stages of NSCLC may help elucidate the histological distinctions of tumors through identification of different gene-mediated biological processes involved in the pathogenesis of histologically distinct tumors. However, we showed here that the gene expression profiles did not provide additional value in predicting the progression status of the early-stage NSCLC. Nevertheless, the gene expression signature analysis enabled us to perform a reliable subclassification of NSCLC tumors, and it can therefore become a useful diagnostic tool for a more accurate selection of patients for targeted therapies. 相似文献
8.
9.
Gregor Kozlowski Sandra Bürcher Matthieu Fleury Fanny Huber 《Biodiversity and Conservation》2009,18(3):649-662
The purpose of this study was to examine the composition, distribution, ecology, and conservation status of the Atlantic elements
of the Swiss flora. About 195 Atlantic and 80 Mediterranean–Atlantic vascular plant species of the European flora have been
used as the basis for our analysis. The complete list of 3,143 taxa has been used as the reference for the Swiss flora. The
distributions of the species are illustrated in coincidence maps based on the computer database of the Data Centre of the
Swiss Flora in Geneva, Switzerland. Our study demonstrates clearly that the Atlantic flora of Europe requires a new biogeographical
appraisal. The Swiss flora comprises 66 Atlantic and Mediterranean–Atlantic taxa, which are taxonomically and ecologically
highly diverse. Switzerland contains 44% of all European Sub-Atlantic plants. This confirms the Sub-Atlantic geographical
position of Switzerland. Only one Eu-Atlantic species growing in Switzerland, Vicia orobus, can be classified as native with certainty. This species is critically endangered and merits the highest conservation priority.
Although a very alpine country, Switzerland has a relatively large number of Mediterranean–Atlantic species. The Atlantic
and Mediterranean–Atlantic plants are a very threatened group in Switzerland, with wetland plants the most imperilled ecological
group.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
10.
Nagendran Muthusamy Sanaa A. Ahmed Brinda K. Rana Sammy Navarre David J. Kozlowski David A. Liberles Clare Bergson 《Journal of molecular evolution》2009,69(4):319-332
Endocytosis and vesicle trafficking are required for optimal neural transmission. Yet, little is currently known about the
evolution of neuronal proteins regulating these processes. Here, we report the first phylogenetic study of NEEP21, calcyon,
and P19, a family of neuronal proteins implicated in synaptic receptor endocytosis and recycling, as well as in membrane protein
trafficking in the somatodendritic and axonal compartments of differentiated neurons. Database searches identified orthologs
for P19 and NEEP21 in bony fish, but not urochordate or invertebrate phyla. Calcyon orthologs were only retrieved from mammalian
databases and distant relatives from teleost fish. In situ localization of the P19 zebrafish ortholog, and extant progenitor
of the gene family, revealed a CNS specific expression pattern. Based on non-synonymous nucleotide substitution rates, the
calcyon genes appear to be under less intense negative selective pressure. Indeed, a functional group II WW domain binding
motif was detected in primate and human calcyon, but not in non-primate orthologs. Sequencing of the calcyon gene from 80
human subjects revealed a non-synonymous single nucleotide polymorphism that abrogated group II WW domain protein binding.
Altogether, our data indicate the NEEP21/calcyon/P19 gene family emerged, and underwent two rounds of gene duplication relatively
late in metazoan evolution (but early in vertebrate evolution at the latest). As functional studies suggest NEEP21 and calcyon
play related, but distinct roles in regulating vesicle trafficking at synapses, and in neurons in general, we propose the
family arose in chordates to support a more diverse range of synaptic and behavioral responses. 相似文献