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991.
Since 1990 when the first clinical gene therapy trial was conducted, much attention and considerable promise have been given to this form of treatment. Gene therapy has been used with success in patients suffering from severe combined immunodeficiency syndromes (X-SCID and ADA-deficiency), Leber's congenital amaurosis, hemophilia, β-thalassemia and adrenoleukodystrophy. Last year, the first therapeutic vector (Glybera) for treatment of lipoprotein lipase deficiency has been registered in the European Union. Nevertheless, there are still several numerous issues that need to be improved to make this technique more safe, effective and easily accessible for patients. 相似文献
992.
The quality of RNA is crucial in gene expression experiments. RNA degradation interferes in the measurement of gene expression, and in this context, microRNA quantification can lead to an incorrect estimation. In the present study, two different RNA isolation methods were used to perform microRNA microarray analysis on porcine brain tissue. One method is a phenol-guanidine isothiocyanate-based procedure that permits isolation of total RNA. The second method, miRVana? microRNA isolation, is column based and recovers the small RNA fraction alone. We found that microarray analyses give different results that depend on the RNA fraction used, in particular because some microRNAs appear very sensitive to the RNA isolation method. We conclude that precautions need to be taken when comparing microarray studies based on RNA isolated with different methods. 相似文献
993.
p53 universe is composed of a complex regulatory network, destined to counteract multifarious challenges threatening cell survival. Imbalance in those responses may result in human disease associated with inevitable consequences. The present work delivers our view of the corresponding phenomena, by involving the endothelium defender in meticulously orchestrated events against inflammatory stimuli. Immersing into the great depths of p53 cosmos may lead to promising therapies against devastating disorders, including acute respiratory distress syndrome. 相似文献
994.
Płaczkiewicz Jagoda Chmiel Paulina Malinowska Ewelina Bącal Pawel Kwiatek Agnieszka 《Journal of microbiology (Seoul, Korea)》2020,58(5):405-414
Journal of Microbiology - Neisseria gonorrhoeae, an obligatory human pathogen causes the sexually transmitted disease gonorrhea, which remains a global health problem. N. gonorrhoeae primarily... 相似文献
995.
Agnieszka ?wiklińska Agnieszka Mickiewicz Robert Kowalski Barbara Kortas-Stempak Agnieszka Kuchta Krzysztof Mucha Micha? Makowiecki Anna Gliwińska Krzysztof Lewandowski Leszek P?czek Marcin Fija?kowski Marcin Grucha?a Maciej Jankowski 《Journal of Medical Biochemistry》2020,39(3):283
BackgroundLipoprotein X (LpX) is an abnormal lipoprotein fraction, which can be detected in patients with severe hypercholesterolaemia and cholestatic liver disease. LpX is composed largely of phospholipid and free cholesterol, with small amounts of triglyceride, cholesteryl ester and protein. There are no widely available methods for direct measurement of LpX in routine laboratory practice. We present the heterogeneity of clinical and laboratory manifestations of the presence of LpX, a phenomenon which hinders LpX detection.MethodsThe study was conducted on a 26-year-old female after liver transplantation (LTx) with severely elevated total cholesterol (TC) of 38 mmol/L and increased cholestatic liver enzymes. TC, free cholesterol (FC), cholesteryl esters (CE), triglycerides, phospholipids, HDL-C, LDL-C, and apolipoproteins AI and B were measured. TC/apoB and FC:CE ratios were calculated. Lipoprotein electrophoresis was performed using a commercially available kit and laboratory-prepared agarose gel.ResultsCommercially available electrophoresis failed to demonstrate the presence of LpX. Laboratory-prepared gel clearly revealed the presence of lipoproteins with γ mobility, characteristic of LpX. The TC/apoB ratio was elevated and the CE level was reduced, confirming the presence of LpX. Regular lipoprotein apheresis was applied as the method of choice in LpX disease and a bridge to reLTx due to chronic liver insufficiency.ConclusionsThe detection of LpX is crucial as it may influence the method of treatment. As routinely available biochemical laboratory tests do not always indicate the presence of LpX, in severe hypercholesterolaemia with cholestasis, any discrepancy between electrophoresis and biochemical tests should raise suspicions of LpX disease. 相似文献
996.
997.
Sebastian Bj?rklund Agnieszka Nowacka Joke A. Bouwstra Emma Sparr Daniel Topgaard 《PloS one》2013,8(4)
Despite the enormous potential for pharmaceutical applications, there is still a lack of understanding of the molecular details that can contribute to increased permeability of the stratum corneum (SC). To investigate the influence of hydration and heating on the SC, we record the natural-abundance 13C signal of SC using polarization transfer solid-state NMR methods. Resonance lines from all major SC components are assigned. Comparison of the signal intensities obtained with the INEPT and CP pulse sequences gives information on the molecular dynamics of SC components. The majority of the lipids are rigid at 32°C, and those lipids co-exist with a small pool of mobile lipids. The ratio between mobile and rigid lipids increases with hydration. An abrupt change of keratin filament dynamics occurs at RH = 80–85%, from completely rigid to a structure with rigid backbone and mobile protruding terminals. Heating has a strong effect on the lipid mobility, but only a weak influence on the keratin filaments. The results provide novel molecular insight into how the SC constituents are affected by hydration and heating, and improve the understanding of enhanced SC permeability, which is associated with elevated temperatures and SC hydration. 相似文献
998.
Philipp Assmy Jens K. Ehn Mar Fernández-Méndez Haakon Hop Christian Katlein Arild Sundfjord Katrin Bluhm Malin Daase Anja Engel Agneta Fransson Mats A. Granskog Stephen R. Hudson Svein Kristiansen Marcel Nicolaus Ilka Peeken Angelika H. H. Renner Gunnar Spreen Agnieszka Tatarek Jozef Wiktor 《PloS one》2013,8(10)
During two consecutive cruises to the Eastern Central Arctic in late summer 2012,
we observed floating algal aggregates in the melt-water layer below and between
melting ice floes of first-year pack ice. The macroscopic (1-15 cm in diameter)
aggregates had a mucous consistency and were dominated by typical ice-associated
pennate diatoms embedded within the mucous matrix. Aggregates maintained
buoyancy and accumulated just above a strong pycnocline that separated meltwater
and seawater layers. We were able, for the first time, to obtain quantitative
abundance and biomass estimates of these aggregates. Although their biomass and
production on a square metre basis was small compared to ice-algal blooms, the
floating ice-algal aggregates supported high levels of biological activity on
the scale of the individual aggregate. In addition they constituted a food
source for the ice-associated fauna as revealed by pigments indicative of
zooplankton grazing, high abundance of naked ciliates, and ice amphipods
associated with them. During the Arctic melt season, these floating aggregates
likely play an important ecological role in an otherwise impoverished
near-surface sea ice environment. Our findings provide important observations
and measurements of a unique aggregate-based habitat during the 2012 record sea
ice minimum year. 相似文献
999.
Magdalena Gorska Antonella Marino Gammazza Michal Aleksander Zmijewski Claudia Campanella Francesco Cappello Tomasz Wasiewicz Alicja Kuban-Jankowska Agnieszka Daca Alicja Sielicka Urszula Popowska Narcyz Knap Jakub Antoniewicz Takashi Wakabayashi Michal Wozniak 《PloS one》2013,8(8)
Osteosarcoma is one of the most malignant tumors of childhood and adolescence that is often resistant to standard chemo- and radio-therapy. Geldanamycin and geldanamycin analogs have been recently studied as potential anticancer agents for osteosarcoma treatment. Here, for the first time, we have presented novel anticancer mechanisms of geldanamycin biological activity. Moreover, we demonstrated an association between the effects of geldanamycin on the major heat shock proteins (HSPs) and the overall survival of highly metastatic human osteosarcoma 143B cells. We demonstrated that the treatment of 143B cells with geldanamycin caused a subsequent upregulation of cytoplasmic Hsp90 and Hsp70 whose activity is at least partly responsible for cancer development and drug resistance. On the other hand, geldanamycin induced upregulation of Hsp60 gene expression, and a simultaneous loss of hyperacetylated Hsp60 mitochondrial protein pool resulting in decreased viability and augmented cancer cell death. Hyperacetylation of Hsp60 seems to be associated with anticancer activity of geldanamycin. In light of the fact that mitochondrial dysfunction plays a critical role in the apoptotic signaling pathway, the presented data may support a hypothesis that Hsp60 can be another functional part of mitochondria-related acetylome being a potential target for developing novel anticancer strategies. 相似文献
1000.
Tomasz Tronina Agnieszka Bartmańska Beata Filip-Psurska Joanna Wietrzyk Jarosław Popłoński Ewa Huszcza 《Bioorganic & medicinal chemistry》2013,21(7):2001-2006
Xanthohumol (1) and xanthohumol D (2) were isolated from spent hops. Isoxanthohumol (3) was obtained from xanthohumol by isomerisation in alkaline solution. Six metabolites were obtained as a result of transformation of xanthohumol (1) by selected fungal cultures. Their structures were established on the basis of their spectral data. One of them: 2″-(2′′′-hydroxyisopropyl)-dihydrofurano-[4″,5″:3′,4′]-4′,2-dihydroxy-6′-methoxy-α,β-dihydrochalcone (6) has not been previously reported in the literature. The antioxidant properties of hops flavonoids and xanthohumol derivatives were investigated using the 2,2′-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method. The effects of these compounds on proliferation of MCF-7, PC-3 and HT-29 human cancer cell lines were determined by the SRB assay. With the exception of one metabolite, all tested compounds showed antiproliferative activity against the tested human cancer lines. α,β-Dihydroxanthohumol (4), obtained through the biotransformation of xanthohumol, showed higher antiproliferative activity against MCF-7 human breast carcinoma cell line than cisplatin, a widely used anticancer therapeutic agent, and a comparably high activity against PC-3 human prostate cancer cell line. 相似文献