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21.
Tarnoki AD Tarnoki DL Stazi MA Medda E Cotichini R Nisticò L Fagnani C Lucatelli P Boatta E Zini C Fanelli F Baracchini C Meneghetti G Osztovits J Jermendy G Préda I Kiss RG Metneki J Horvath T Karlinger K Racz A Lannert A Molnar AA Littvay L Garami Z Berczi V Schillaci G 《Journal of hypertension》2012,30(8):1564-1571
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Brian A. Reikie Shalena Naidoo Candice E. Ruck Amy L. Slogrove Corena de Beer Heleen la Grange Rozanne C. M. Adams Kevin Ho Kinga Smolen David P. Speert Mark F. Cotton Wolfgang Preiser Monika Esser Tobias R. Kollmann 《Clinical and Vaccine Immunology : CVI》2013,20(1):33-38
HIV-exposed but uninfected (HEU) infants born to HIV-infected mothers from areas in the world with a high burden of infectious disease suffer higher infectious morbidity and mortality than their HIV unexposed uninfected (HUU) peers. Vaccination provides protection from infection. The possibility exists that altered response to vaccination contributes to the higher rate of infection in HEU than in HUU infants. While short-term, cross-sectional studies support this notion, it is unclear whether or not HEU infants develop long-term protective immune responses following the WHO extended program on immunization (EPI). Vaccine-specific antibody responses were compared between HEU and HUU infants from 2 weeks until 2 years of age in a longitudinal South African cohort. Total IgG and antibodies specific for Bordetella pertussis, Haemophilus influenzae type b (Hib), tetanus toxoid, hepatitis B virus (HepB), and measles virus were measured at multiple time points throughout the first 2 years of life. Prevaccine antibodies (maternal antibodies passively acquired) specific for tetanus were lower in HEU than in HUU infants, while prevaccine antibodies to HepB were higher in HEU than in HUU infants. Both groups responded similarly to tetanus, Hib, and HepB vaccination. HEU demonstrated stronger pertussis vaccine responses, developing protective titers 1 year earlier than HUU patients, and maintained higher anti-tetanus titers at 24 months of age. Vaccine-induced antibodies to measles virus were similar in both groups at all time points. Our results suggest that the current EPI vaccination program as practiced in South Africa leads to the development of vaccine-specific antibody responses that are equivalent in HEU and HUU infants. However, our data also suggest that a large fraction of both HEU and HUU South African infants have antibody titers for several infectious threats that remain below the level of protection for much of their first 2 years of life. 相似文献
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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
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In an auditory oddball task emotionally negative (aversive) sounds (e.g. rubbing together of polystyrene) and everyday sounds (e.g. ringing of a bicycle bell) were presented as task-irrelevant (novel) sounds. Both the aversive and the everyday sounds elicited the orientation-related P3a component of the event-related potentials (ERPs). In the 154–250 ms range the ERPs for the aversive sounds were more negative than the ERP of the everyday sounds. For the aversive sounds, this negativity was followed by a frontal positive wave (372–456 ms). The aversive sounds elicited larger late positive shift than the everyday sounds. The early negativity is considered as an initial effect in a broad neural network including limbic structures, while the later is related to the cognitive assessment of the stimuli and to memory-related processes. 相似文献
27.
Krzysztof Zakowski Juliusz Orlikowski Kazimierz Darowicki Marcin Czekajlo Piotr Iglinski Kinga Domanska 《Materials》2021,14(7)
Al-Zn-In alloys having 4.2% zinc content and various indium content in the range of 0.02–0.2% were tested with respect to the most important electrochemical properties of sacrificial anodes in a cathodic protection, i.e., the current capacity and potential of the operating anode. The distribution of In and Zn in the tested alloys was mapped by means of the EDX technique, which demonstrated that these elements dissolve well in the alloy matrix and are evenly distributed within it. The current capacity of such alloys was determined by means of the method of determining the mass loss during the dissolution by a current of known charge. The results obtained demonstrate that the current capacity of Al-Zn-In alloy decreases with the increase in the In content, which results in an increased consumption of anode material and shorter lifetime of anodes. With 0.02% In content, the capacity amounted to approx. 2500 Ah/kg, whereas the alloy with 0.2% In had as much as 30% lower capacity amounting to approx. 1750 Ah/kg. Microscopic examination for the morphology and surface profile of the samples after their exposure demonstrated that a higher indium content in the alloy results in a more uneven general corrosion pattern during the dissolution of such alloy, and the cavities (pits) appearing on the alloy surface are larger and deeper. As the indium content is increased from 0.02% to 0.05%, the Al-Zn-In alloy potential decreases by about 50 mV to −1100 mV vs. Ag/AgCl electrode, which is advantageous in terms of using this alloy as a sacrificial anode. When the indium content is further increased from 0.05% to 0.2%, the potential of the alloy is no longer changed to a more negative one. The results obtained from all these tests demonstrate that alloys containing up to 0.05% of In additive are practically applicable for cathodic protection. 相似文献
28.
Marta Babicka Magdalena Wo
niak Kinga Szentner Monika Bartkowiak Barbara Pepliska Krzysztof Dwiecki Sawomir Borysiak Izabela Ratajczak 《Materials》2021,14(12)
Nanocellulose has gained increasing attention during the past decade, which is related to its unique properties and wide application. In this paper, nanocellulose samples were produced via hydrolysis with ionic liquids (1-ethyl-3-methylimidazole acetate (EmimOAc) and 1-allyl-3-methylimidazolium chloride (AmimCl)) from microcrystalline celluloses (Avicel and Whatman) subjected to enzymatic pretreatment. The obtained material was characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), dynamic light scattering (DLS), scanning electron microscopy (SEM), and thermogravimetric analysis (TG). The results showed that the nanocellulose had a regular and spherical structure with diameters of 30–40 nm and exhibited lower crystallinity and thermal stability than the material obtained after hydrolysis with Trichoderma reesei enzymes. However, the enzyme-pretreated Avicel had a particle size of about 200 nm and a cellulose II structure. A two-step process involving enzyme pretreatment and hydrolysis with ionic liquids resulted in the production of nanocellulose. Moreover, the particle size of nanocellulose and its structure depend on the ionic liquid used. 相似文献
29.
This paper presents the results of research on geopolymer composites based on fly ash with the addition of melamine fibers in amounts of 0.5%, 1% and 2% by weight and, for comparison, without the addition of fibers. The melamine fibers used in the tests retain their melamine resin properties by 100% and are characterized by excellent acoustic and thermal insulation as well as excellent filtration. In addition, these fibers are nonflammable, resistant to chemicals, resistant to UV radiation, characterized by high temperature resistance and, most importantly, do not show thermal-related shrinking, melting and dripping. This paper presents the results of density measurements, compressive and flexural strength as well as the results of the measurement of thermal radiation changes in samples subjected to a temperature of 600 °C. The results indicate that melamine fibers can be used as geopolymer reinforcement. The best result was achieved for 0.5% by weight amount of reinforcement, approximately 53 MPa, compared to 41 MPa for a pure matrix. In the case of flexural strength, the best results were obtained for the samples made of unreinforced geopolymer and samples with the addition of 0.5% by weight of melamine fibers, which were characterized by bending strength values above 9 MPa, amounting to 10.7 MPa and 9.3 MPa, respectively. The thermal radiation measurements and fire-jet test did not confirm the increasing thermal and fire resistance of the composites reinforced by melamine fiber. 相似文献
30.
Paweł Krawczyk Tomasz Kucharczyk Dariusz M. Kowalski Tomasz Powrózek Rodryg Ramlau Ewa Kalinka-Warzocha Kinga Winiarczyk Magdalena Knetki-Wróblewska Kamila Wojas-Krawczyk Katarzyna Kałakucka Wojciech Dyszkiewicz Maciej Krzakowski Janusz Milanowski 《Journal of cancer research and clinical oncology》2014,140(12):2047-2057