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21.
Herpes simplex virus types 1 and 2 HSV1 and 2, namely varicella-zoster VZV and cytomegalovirus CMV, are among the most common pathogens worldwide. They remain in the host body for life. The course of infection with these viruses is often asymptomatic or mild and self-limiting, but in immunocompromised patients, such as solid organ or bone marrow transplant recipients, the course can be very severe or even life-threatening. Unfortunately, in the latter group, the highest percentage of infections with strains resistant to routinely used drugs is observed. On the other hand, frequent recurrences of genital herpes can be a problem even in people with normal immunity. Genital herpes also increases the risk of acquiring sexually transmitted diseases, including HIV infection and, if present in pregnant women, poses a risk to the fetus and newborn. Even more frequently than herpes simplex, congenital infections can be caused by cytomegalovirus. We present the most important anti-herpesviral agents, the mechanisms of resistance to these drugs, and the associated mutations in the viral genome. Special emphasis was placed on newly introduced drugs such as maribavir and brincidofovir. We also briefly discuss the most promising substances in preclinical testing as well as immunotherapy options and vaccines currently in use and under investigation. 相似文献
22.
Kamil Cebulski Katarzyna Nowiska Karolina Jabloska Hanna Romanowicz Beata Smolarz Piotr Dzigiel Marzenna Podhorska-Okow 《International journal of molecular sciences》2022,23(7)
Irisin is a myokine formed from fibronectin type III domain-containing protein 5 (FNDC5), which can be found in various cancer tissues. FNDC5 and irisin levels have been poorly studied in the tumor tissues of breast cancer (BC). The aim of this study was to determine the levels of irisin expression in BC tissues and compare them to clinicopathological factors and Ki-67 and PGC-1α expression levels. Tissue microarrays (TMAs) with 541 BC tissues and 61 samples of non-malignant breast disease (NMBD; control) were used to perform immunohistochemical reactions. FNDC5 gene expression was measured in 40 BC tissue samples, 40 samples from the cancer margin, and 16 NMBD samples. RT-PCR was performed for the detection of FNDC5 gene expression. Higher irisin expression was found in BC patients compared to normal breast tissue. FNDC5/irisin expression was higher in patients without lymph node metastases. Longer overall survival was observed in patients with higher irisin expression levels. FNDC5/irisin expression was increased in BC tissues and its high level was a good prognostic factor for survival in BC patients. 相似文献
23.
Mechanism of MxOy nanoparticles/CNTs for catalytic carbonization of polyethylene and application to flame retardancy 下载免费PDF全文
Karolina Wenelska Xuecheng Chen Beata Zielinska Ryszard J. Kaleńczuk Paul K. Chu Tao Tang Ewa Mijowska 《应用聚合物科学杂志》2017,134(34)
Three kinds of metal oxide nanoparticles (Fe3O4, Co3O4, and Ni2O3) are produced on carbon nanotubes (CNTs). The synergistic effects rendered by the CNTs and metal oxide nanoparticles on carbonization of polyethylene (PE) are studied and applications to flame retardancy of PE are investigated systematically. The CNT‐Ni2O3 delivers the best performance and the mechanism pertaining to the enhanced flame retardancy is proposed and discussed. It is found that under the same conditions, the carbonization rate can be a factor to influence the flame retardancy performance. Among Fe, Co, and Ni, Ni has the fastest carbonation rate, which leads to the best flame retardancy performance. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45233. 相似文献
24.
Beata Tryba Antoni W. Morawski Michio Inagaki Masahiro Toyoda 《Applied catalysis. B, Environmental》2006,63(3-4):215-221
H2O2 used in the photo-Fenton reaction with iron catalyst can accelerate the oxidation of Fe2+ to Fe3+ under UV irradiation and in the dark (in the so called dark Fenton process). It was proved that conversion of phenol under UV irradiation in the presence of H2O2 predominantly produces highly hydrophilic products and catechol, which can accelerate the rate of phenol decomposition. However, while H2O2 under UV irradiation could decompose phenol to highly hydrophilic products and dihydroxybenzenes in a very short time, complete mineralization proceeded rather slowly. When H2O2 is used for phenol decomposition in the presence of TiO2 and Fe–TiO2, decrease of OH radicals formed on the surface of TiO2 and Fe–TiO2 has been observed and photodecomposition of phenol is slowed down. In case of phenol decomposition under UV irradiation on Fe–C–TiO2 photocatalyst in the presence of H2O2, marked acceleration of the decomposition rate is observed due to the photo-Fenton reactions: Fe2+ is likely oxidized to Fe3+, which is then efficiently recycled to Fe2+ by the intermediate products formed during phenol decomposition, such as hydroquinone (HQ) and catechol. 相似文献
25.
Absorption and photoreflectance spectroscopy of zinc phthalocyanine (ZnPc) thin films grown by thermal evaporation 总被引:1,自引:0,他引:1
Optical properties of the as-deposited and annealed ZnPc layers have been investigated using absorption, reflectance and modulated photoreflectance methods. The absorption coefficient of ZnPc layers was directly determined from the transmission and reflection spectra. The absorption spectra were analyzed in terms of the mixed Lorentz–Lorenz model. We found that annealing thin layers at 580 K caused a structural transformation, which results in the decrease of the absorption coefficient and the shifting of all peak position to lower energies except for the peak of the N-band. Photoreflectance spectroscopy confirmed that there exist three transitions in the Q-band region of the studied material. Complex refractive index and dielectric constants of the ZnPc layer were directly found from the spectral data. 相似文献
26.
Wojciech Zalewski Beata Niezgoda-
elasko Marek Litwin 《International Journal of Refrigeration》2000,23(7):553
In the paper the optimization of geometrical and operating parameters for evaporative fluid coolers has been presented. The algorithm of optimizational calculations contains:
- • the mathematical model of heat and mass transfer in evaporative fluid coolers;
- • model of operating costs based, among others, on the Zalewski–Gryglaszewski relations developed by the authors for evaluation of air pressure drops in the heat exchanger;
- • model of evaporative heat exchangers production costs.
27.
Beata Kucieńska Graciela B. Raga Victor Manuel Torres-Puente 《International journal of remote sensing》2013,34(9):2831-2850
Tropical Rainfall Measuring Mission (TRMM) satellite products for the period 1998–2009 are used to elaborate the climatology of vertical hydrometeor profiles and diurnal evolution of rainfall over the Pacific coast of southern Mexico. Precipitation characteristics are compared with those of lightning strokes, registered by the World Wide Lightning Location Network (WWLLN). The WWLLN data are verified against a climatological product (High-Resolution Monthly Climatology, HRMC) obtained from merged data sets of the TRMM Lightning Imaging Sensor (LIS) and the Optical Transient Detector (OTD) of the MicroLab-1 satellite. The TRMM 2A12 data set reveals that summer precipitation over the study region is a result of mixed phase processes, whereas during winter and spring, there is a significant contribution of warm precipitation over land. Diurnal evolution of rainfall retrieved from the 3B42 TRMM product and lightning registered by the WWLLN follows the sea–land breeze cycle measured by Baumgardner et al. (2006; Evolution of anthropogenic aerosols in the coastal town of Salina Cruz, Mexico: part I particle dynamics and land–sea interactions, Science of the Total Environment, 367, pp. 288–301). The spatial distribution of lightning is similar to that of rainfall; however, over the seaside coastal region, a phase shift is observed between these two variables, with the maximum lightning activity occurring about 3 hours before the precipitation peak. Monthly distribution of flashes is monomodal over land and bimodal over the ocean. Over the ocean, the evolution of monthly rainfall during summer is contrary to that of lightning activity: the months with highest precipitation (June and September) correspond to those with the lowest number of lightning strokes, whereas during the mid-summer drought, an increase in electrical activity is observed. An explanation for this phenomenon, related to the wind circulation and its effect on the concentration of aerosol particles, is proposed. 相似文献
28.
Beata Podkościelna 《应用聚合物科学杂志》2011,120(5):3020-3026
Synthesis, copolymerization, and physicochemical properties of new, of different degrees of crosslinker tetrafunctional bis[4(2‐hydroxy‐3‐methacryloyloxypropoxy)phenyl]sulfide and glycidyl methacrylate copolymers are presented. The monomers were used for the synthesis of porous microspheres in the presence of pore‐forming diluents, decan‐1‐ol, and toluene. Influence of diluents composition on their porous structures was studied. Porous structure of the obtained microspheres in dry (from nitrogen adsorption–desorption measurements) states was studied. Their chemical structures were studied by the use of Fourier transform infrared. The number of epoxy groups of the obtained copolymers, their thermal properties (thermogravimetric analysis), and swelling characteristics in 10 solvents of different chemical nature were examined. Selected copolymers were modified by amines in the epoxide ring‐opening reaction. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
29.
Lara Valentín Beata Kluczek‐Turpeinen Pekka Oivanen Annele Hatakka Kari Steffen Marja Tuomela 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(6):851-858
BACKGROUND: For most dioxin‐contaminated sawmill soils, combustion is recommended. However, the process may be inefficient if the soil has a high organic matter content. The use of saprotrophic basidiomycetous fungi is an alternative for pretreatment of this kind of soil. A total of 147 fungi were evaluated for their ability to grow in sawmill soil. From this screening, the best soil colonizing fungi were selected to study their enzyme activities and degradation of soil organic matter. Pine (Pinus sylvestris) bark was used as a co‐substrate to propagate the fungi into the soil. The activities of manganese peroxidase (MnP), laccase, endo‐1,4‐β‐glucanase, endo‐1,4‐β‐xylanase, and endo‐1,4‐β‐mannanase were analysed from the inocula and fungal treated soil. RESULTS: The screening revealed that 56 out of 147 fungi were able to grow in non‐sterile soil, and most of them were litter‐decomposing fungi (LDF). In pine bark cultures, the highest enzyme activities were observed with Phanerochaete velutina, which produced 5 U g?1 of MnP. The activity of endo‐1,4‐β‐glucanase was generally higher than that of other hydrolytic enzymes. The highest carbon loss from soil with a high organic matter content was achieved by P. velutina (3.4%) and Stropharia rugosoannulata (2.4%). CONCLUSIONS: Many LDF, and in addition the white‐rot fungus P. velutina, are potential degraders of soil organic matter since they showed good growth and respiratory activity. Pine bark was a suitable lignocellulosic co‐substrate and a good promoter of MnP activity. Copyright © 2009 Society of Chemical Industry 相似文献
30.
Aneta Stachowicz Anna Winiewska Katarzyna Ku Magdalena Biaas Magdalena omnicka Justyna Toto-uraska Anna Kiepura Kamila Stachyra Maciej Suski Beata Bujak-Giycka Jacek Jawie Rafa Olszanecki 《International journal of molecular sciences》2021,22(11)
Atherosclerosis and nonalcoholic fatty liver disease are leading causes of morbidity and mortality in the Western countries. The renin–angiotensin system (RAS) with its two main opposing effectors, i.e., angiotensin II (Ang II) and Ang-(1–7), is widely recognized as a major regulator of cardiovascular function and body metabolic processes. Angiotensin-converting enzyme 2 (ACE2) by breaking-down Ang II forms Ang-(1–7) and thus favors Ang-(1–7) actions. Therefore, the aim of our study was to comprehensively evaluate the influence of prolonged treatment with ACE2 activator, diminazene aceturate (DIZE) on the development of atherosclerotic lesions and hepatic steatosis in apoE−/− mice fed a high-fat diet (HFD). We have shown that DIZE stabilized atherosclerotic lesions and attenuated hepatic steatosis in apoE−/− mice fed an HFD. Such effects were associated with decreased total macrophages content and increased α-smooth muscle actin levels in atherosclerotic plaques. Moreover, DIZE changed polarization of macrophages towards increased amount of anti-inflammatory M2 macrophages in the atherosclerotic lesions. Interestingly, the anti-steatotic action of DIZE in the liver was related to the elevated levels of HDL in the plasma, decreased levels of triglycerides, and increased biosynthesis and concentration of taurine in the liver of apoE−/− mice. However, exact molecular mechanisms of both anti-atherosclerotic and anti-steatotic actions of DIZE require further investigations. 相似文献