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101.
102.
Hoffmann G Gufler V Griesmacher A Bartenbach C Canazei M Staggl S Schobersberger W 《Applied ergonomics》2008,39(6):719-728
Workplace illumination is of paramount importance in determining the employee's productivity and well-being. Moreover, light exerts non-visual effects with respect to biological rhythms. In this study, we investigated the impact of different lighting conditions (500-1800 lx, 6500 K; 500 lx, 4000 K) on sulphatoxymelatonin (aMT6-s) and subjective mood in an experimental office accommodation. Urinary aMT6-s concentrations were significantly decreased at all days of the experiment in both lights. On day 3, differences between aMT6-s concentrations in specimen collected at 05:00 p.m. and at 09:00 a.m. were significantly higher under variable lighting conditions. Analyses of a mood rating inventory revealed a benefit of variable light with respect to the dimensions of "Activity", while "Deactivation" and "Fatigue" were increased in regular light on day 1. "Activity", "Concentration", and "Deactivation" changed in opposite directions when comparing variable with regular illumination on two consecutive days. In conclusion, variable light exerts a potential advantage in indoor office accommodations with respect to subjective mood, although no unequivocal differences in the profile of aMT6-s were found as compared to regular light. 相似文献
103.
Ale Igli
Margaret Tzaphlidou Maja Rem kar Bla Babnik Matej Daniel Veronika Kralj-Igli
《Fullerenes, Nanotubes and Carbon Nanostructures》2005,13(3):183-192
The elastic properties of a thin anisotropic nano-strip are characterized by its intrinsic mean curvature and intrinsic curvature deviator. It is shown that minimization of the elastic energy of the strip including the deviatoric contribution may explain the stability of the observed helical and twisted shapes of inorganic nano-strips (helix A and B). 相似文献
104.
Mario García-Risco Sara Calatayud Veronika Pedrini-Martha Ricard Albalat Reinhard Dallinger
scar Palacios Merc Capdevila 《International journal of molecular sciences》2021,22(23)
Metallothioneins’ (MTs) biological function has been a matter of debate since their discovery. The importance to categorize these cysteine-rich proteins with high coordinating capacity into a specific group led to numerous classification proposals. We proposed a classification based on their metal-binding abilities, gradually sorting them from those with high selectivity towards Zn/Cd to those that are Cu-specific. However, the study of the NpeMT1 and NpeMT2isoforms of Nerita peloronta, has put a new perspective on this classification. N. peloronta has been chosen as a representative mollusk to elucidate the metal-binding abilities of Neritimorpha MTs, an order without any MTs characterized recently. Both isoforms have been recombinantly synthesized in cultures supplemented with ZnII, CdII, or CuII, and the purified metal–MT complexes have been thoroughly characterized by spectroscopic and spectrometric methods, leading to results that confirmed that Neritimorpha share Cd-selective MTs with Caenogastropoda and Heterobranchia, solving a so far unresolved question. NpeMTs show high coordinating preferences towards divalent metal ions, although one of them (NpeMT1) shares features with the so-called genuine Zn-thioneins, while the other (NpeMT2) exhibits a higher preference for Cd. The dissimilarities between the two isoforms let a window open to a new proposal of chemical MT classification. 相似文献
105.
106.
Viktor Hlav
Radka Vclavíkov Veronika Brynychov Renata Koevnikovov Katerina Kope
kov David Vrna Jií Gatk Pavel Sou
ek 《International journal of molecular sciences》2020,21(24)
Breast cancer is the most common cancer in women in the world. The role of germline genetic variability in ATP-binding cassette (ABC) transporters in cancer chemoresistance and prognosis still needs to be elucidated. We used next-generation sequencing to assess associations of germline variants in coding and regulatory sequences of all human ABC genes with response of the patients to the neoadjuvant cytotoxic chemotherapy and disease-free survival (n = 105). A total of 43 prioritized variants associating with response or survival in the above testing phase were then analyzed by allelic discrimination in the large validation set (n = 802). Variants in ABCA4, ABCA9, ABCA12, ABCB5, ABCC5, ABCC8, ABCC11, and ABCD4 associated with response and variants in ABCA7, ABCA13, ABCC4, and ABCG8 with survival of the patients. No association passed a false discovery rate test, however, the rs17822931 (Gly180Arg) in ABCC11, associating with response, and the synonymous rs17548783 in ABCA13 (survival) have a strong support in the literature and are, thus, interesting for further research. Although replicated associations have not reached robust statistical significance, the role of ABC transporters in breast cancer should not be ruled out. Future research and careful validation of findings will be essential for assessment of genetic variation which was not in the focus of this study, e.g., non-coding sequences, copy numbers, and structural variations together with somatic mutations. 相似文献
107.
Pavel Rossner Jr. Simona Strapacova Jitka Stolcpartova Jana Schmuczerova Alena Milcova Jiri Neca Veronika Vlkova Tana Brzicova Miroslav Machala Jan Topinka 《International journal of molecular sciences》2016,17(9)
We investigated the toxicity of benzo[a]pyrene (B[a]P), 1-nitropyrene (1-NP) and 3-nitrobenzanthrone (3-NBA) in A549 cells. Cells were treated for 4 h and 24 h with: B[a]P (0.1 and 1 μM), 1-NP (1 and 10 μM) and 3-NBA (0.5 and 5 μM). Bulky DNA adducts, lipid peroxidation, DNA and protein oxidation and mRNA expression of CYP1A1, CYP1B1, NQO1, POR, AKR1C2 and COX2 were analyzed. Bulky DNA adducts were induced after both treatment periods; the effect of 1-NP was weak. 3-NBA induced high levels of bulky DNA adducts even after 4-h treatment, suggesting rapid metabolic activation. Oxidative DNA damage was not affected. 1-NP caused protein oxidation and weak induction of lipid peroxidation after 4-h incubation. 3-NBA induced lipid peroxidation after 24-h treatment. Unlike B[a]P, induction of the aryl hydrocarbon receptor, measured as mRNA expression levels of CYP1A1 and CYP1B1, was low after treatment with polycyclic aromatic hydrocarbon (PAH) nitro-derivatives. All test compounds induced mRNA expression of NQO1, POR, and AKR1C2 after 24-h treatment. AKR1C2 expression indicates involvement of processes associated with reactive oxygen species generation. This was supported further by COX2 expression induced by 24-h treatment with 1-NP. In summary, 3-NBA was the most potent genotoxicant, whereas 1-NP exhibited the strongest oxidative properties. 相似文献
108.
Tomas Strharsky Dominika Pindjakova Jiri Kos Lucia Vrablova Hana Michnova Jan Hosek Nicol Strakova Veronika Lelakova Lenka Leva Lenka Kavanova Michal Oravec Alois Cizek Josef Jampilek 《International journal of molecular sciences》2022,23(6)
A series of eighteen 4-chlorocinnamanilides and eighteen 3,4-dichlorocinnamanilides were designed, prepared and characterized. All compounds were evaluated for their activity against gram-positive bacteria and against two mycobacterial strains. Viability on both cancer and primary mammalian cell lines was also assessed. The lipophilicity of the compounds was experimentally determined and correlated together with other physicochemical properties of the prepared derivatives with biological activity. 3,4-Dichlorocinnamanilides showed a broader spectrum of action and higher antibacterial efficacy than 4-chlorocinnamanilides; however, all compounds were more effective or comparable to clinically used drugs (ampicillin, isoniazid, rifampicin). Of the thirty-six compounds, six derivatives showed submicromolar activity against Staphylococcus aureus and clinical isolates of methicillin-resistant S. aureus (MRSA). (2E)-N-[3,5-bis(trifluoromethyl)phenyl]- 3-(4-chlorophenyl)prop-2-enamide was the most potent in series 1. (2E)-N-[3,5-bis(Trifluoromethyl)phenyl]-3-(3,4-dichlorophenyl)prop-2-enamide, (2E)-3-(3,4-dichlorophenyl)-N-[3-(trifluoromethyl)phenyl]prop-2-enamide, (2E)-3-(3,4-dichloro- phenyl)-N-[4-(trifluoromethyl)phenyl]prop-2-enamide and (2E)-3-(3,4-dichlorophenyl)- N-[4-(trifluoromethoxy)phenyl]prop-2-enamide were the most active in series 2 and in addition to activity against S. aureus and MRSA were highly active against Enterococcus faecalis and vancomycin-resistant E. faecalis isolates and against fast-growing Mycobacterium smegmatis and against slow-growing M. marinum, M. tuberculosis non-hazardous test models. In addition, the last three compounds of the above-mentioned showed insignificant cytotoxicity to primary porcine monocyte-derived macrophages. 相似文献
109.
Darja Boi
Matej Ho
evar Matic Kisovec Manca Pajni
Ljubia Paen Marko Jeran Apolonija Bedina Zavec Marjetka Podobnik Ksenija Kogej Ale Igli
Veronika Kralj-Igli
《International journal of molecular sciences》2021,22(23)
Extracellular vesicles (EVs) are gaining increasing amounts of attention due to their potential use in diagnostics and therapy, but the poor reproducibility of the studies that have been conducted on these structures hinders their breakthrough into routine practice. We believe that a better understanding of EVs stability and methods to control their integrity are the key to resolving this issue. In this work, erythrocyte EVs (hbEVs) were isolated by centrifugation from suspensions of human erythrocytes that had been aged in vitro. The isolate was characterised by scanning (SEM) and cryo-transmission electron microscopy (cryo-TEM), flow cytometry (FCM), dynamic/static light scattering (LS), protein electrophoresis, and UV-V spectrometry. The hbEVs were exposed to various conditions (pH (4–10), osmolarity (50–1000 mOsm/L), temperature (15–60 °C), and surfactant Triton X-100 (10–500 μM)). Their stability was evaluated by LS by considering the hydrodynamic radius (Rh), intensity of scattered light (I), and the shape parameter (ρ). The morphology of the hbEVs that had been stored in phosphate-buffered saline with citrate (PBS–citrate) at 4 °C remained consistent for more than 6 months. A change in the media properties (50–1000 mOsm/L, pH 4–10) had no significant effect on the Rh (=100–130 nm). At pH values below 6 and above 8, at temperatures above 45 °C, and in the presence of Triton X-100, hbEVs degradation was indicated by a decrease in I of more than 20%. Due to the simple preparation, homogeneous morphology, and stability of hbEVs under a wide range of conditions, they are considered to be a suitable option for EV reference material. 相似文献
110.