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51.
The SARS-CoV-2 infection determines the COVID-19 syndrome characterized, in the worst cases, by severe respiratory distress, pulmonary and cardiac fibrosis, inflammatory cytokine release, and immunosuppression. This condition has led to the death of about 2.15% of the total infected world population so far. Among survivors, the presence of the so-called persistent post-COVID-19 syndrome (PPCS) is a common finding. In COVID-19 survivors, PPCS presents one or more symptoms: fatigue, dyspnea, memory loss, sleep disorders, and difficulty concentrating. In this study, a cohort of 117 COVID-19 survivors (post-COVID-19) and 144 non-infected volunteers (COVID-19-free) was analyzed using pyrosequencing of defined CpG islands previously identified as suitable for biological age determination. The results show a consistent biological age increase in the post-COVID-19 population, determining a DeltaAge acceleration of 10.45 ± 7.29 years (+5.25 years above the range of normality) compared with 3.68 ± 8.17 years for the COVID-19-free population (p < 0.0001). A significant telomere shortening parallels this finding in the post-COVID-19 cohort compared with COVID-19-free subjects (p < 0.0001). Additionally, ACE2 expression was decreased in post-COVID-19 patients, compared with the COVID-19-free population, while DPP-4 did not change. In light of these observations, we hypothesize that some epigenetic alterations are associated with the post-COVID-19 condition, particularly in younger patients (< 60 years).  相似文献   
52.
Multimedia Tools and Applications - At the end of 2019, the World Health Organization (WHO) reported pneumonia that started in Wuhan, China, as a global emergency problem. Researchers quickly...  相似文献   
53.
New polymeric structures obtained by chemical transformations of maleic anhydride/dicyclopentadiene copolymer with triethylenetetraamine, p‐aminobenzoic acid, and p‐aminophenylacetic acid were used for the removal Cu(II) ions from aqueous solutions. The experimental values prove the importance of the chelator nature and of the macromolecular chain geometry for the retention efficiency. The retention efficiency (ηr), the retention capacity (Q e ), and the distribution coefficient of the metal ion into the polymer matrix (K d ) are realized by evaluation of residual Cu(II) ions in the effluent waters, by atomic adsorption. Also are discussed the influence of pH, the thermal stability of the polymer, and their polymer–metal complex, as well as the particular aspects regarding the contact procedure and the batch time. Based on the polymers and polymer–metal complexes characterization a potential retention mechanism is proposed. All polymer supports as well theirs metal–complexes are characterized by ATD and FTIR measurements. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1397–1405, 2007  相似文献   
54.
Considering the challenges related to antimicrobial resistance, other strategies for controlling infections have been suggested, such as antimicrobial photodynamic therapy (aPDT) and antimicrobial peptides (AMP). This study aims to perform a systematic review and meta-analysis to obtain evidence on the antimicrobial effectiveness of aPDT associated with AMP and establish in vitro knowledge on this topic for further study designs. The PubMed, Scopus, Web of Science, Science Direct, Scielo, and Cochrane Library databases were searched. Two independent and calibrated researchers (Kappa = 0.88) performed all the systematic steps according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The odds ratio (OR) was used as the effect measure. The Peto method was used to perform the meta-analysis due to the sparse data. Twenty studies were included in the present review. The result was significant (OR = 0.14/p = 0.0235/I-squared = 0%), showing better outcomes of aPDT associated with peptides than those of aPDT alone for controlling the microbial load. Only 20% of the studies included evaluated this approach in a biofilm culture. Combined treatment with aPDT and AMP highly increased the ability of microbial reduction of Gram-positive and Gram-negative bacteria. However, additional blind studies are required to evaluate the efficacy of this therapy on microbial biofilms.  相似文献   
55.
We demonstrate the multilevel patterning of organic light-emitting polymers by room-temperature nanoimprint lithography (RT-NIL), which is impossible to obtain by conventional hot embossing. In particular, we realize one- and two-dimensional photonic crystals with 500 nm periodic features and investigate the changes in the optical properties (luminescence and quantum yield) of the organic active layer. An increase of the quantum yield by 2.4% for the patterned film with respect to the untextured one and the enhancement of the output light emitted at a particular angle (Theta = 69 degrees) are observed for gratings whose Bragg periodicity matched the emission wavelength of the polymer. The employment of RT-NIL to pattern polymer semiconductors without degradation of their optical properties represents a strategic route for the realization of novel nanopatterned optoelectronic devices.  相似文献   
56.
57.
A method to determine safranal content based on non-polar solvent extraction followed by UV–Vis analysis available in the industry for quality control of saffron spice has been studied. Ultrasound-assisted extraction of safranal was carried out and optimised with respect to the solvent: diethyl ether, hexane and chloroform; the time of extraction; and the concentration of saffron in each organic solvent. Best extraction conditions were obtained when 20 g L?1 of saffron was extracted with chloroform for 15 min. Intra-laboratory validation of the optimised conditions and analysis by UV–Vis spectrophotometry showed satisfactory results in linearity, repeatability, intermediate precision and recovery. The limit of detection was 1 mg safranal kg?1 saffron and the limit of quantification was 3 mg safranal kg?1 saffron.  相似文献   
58.
Reports an error in "Predicting student attitudes about racial diversity and gender equity" by Kevin O. Cokley, Kimberly Tran, Brittany Hall-Clark, Collette Chapman, Luana Bessa, Angela Finley and Michael Martinez (Journal of Diversity in Higher Education, 2010[Sep], Vol 3[3], 187-199). There are two errors in Table 2 under the RWA heading and the Cog-gender heading. The necessary changes are provided in the erratum. (The following abstract of the original article appeared in record 2010-18201-006.) Factors related to attitudes about racial diversity and gender equity were examined in an ethnically diverse sample of 432 college students (167 European Americans, 83 African Americans, 81 Asian Americans, and 82 Hispanic Americans). In addition to variables of self-interest (i.e., ethnicity, gender, and political views), social ideology (i.e., social dominance orientation, right-wing authoritarianism) and personality traits (openness to experience) were uniquely predictive of attitudes about racial diversity and gender equity. Hierarchical regressions revealed that social dominance orientation most strongly predicted racial attitudes, while right-wing authoritarianism most strongly predicted gender attitudes. Implications for diversity education efforts related to prejudice reduction are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
59.
Prostate cancer (PC) is a frequent male malignancy and represents the second most diagnosed cancer in men. Since pre-cancerous lesions, i.e., the high-grade prostatic intraepithelial neoplasia (HGPIN), can be detected years before progression to PC, early diagnosis and chemoprevention are targeted strategies to reduce PC rates. Animal studies have shown that lycopene, a carotenoid contained in tomatoes, is a promising candidate for the chemoprevention of PC. However, its efficacy in humans remains controversial. The present study aimed to investigate the relevance of plasma and prostate concentration of lycopene after a lycopene-enriched diet in patients diagnosed with HGPIN. Thirty-two patients diagnosed with HGPIN were administered a lycopene-enriched diet (20–25 mg/day of lycopene; through 30 g/day of triple concentrated tomato paste) for 6 months. A 6-month follow-up prostate biopsy assessed progression to PC. Patients were classified into three groups according to the histopathological features of the 6-month follow-up biopsy results: prostatitis; HGPIN and PC. PSA and plasma lycopene levels were measured before and after the dietary lycopene supplementation. Prostatic lycopene concentration was only assessed after the supplementation diet. Only prostatic lycopene concentration showed significant differences between the three groups (p = 0.03). Prostatic lycopene concentration below a 1 ng/mg threshold was associated with PC at 6-month follow-up biopsy (p = 0.003). We observed no overall benefits from a 6-month lycopene supplementation, as the rate of HGPIN progression to PC in our population (9/32, 28%) was similar to rates reported in the literature. Baseline PSA levels also showed no significant changes after a lycopene-enriched diet. Our findings point to prostatic lycopene concentration as a promising biomarker of PC. Further prospective longitudinal studies are needed to assess the prognostic role of prostatic lycopene in PC.  相似文献   
60.
This work deals with the deposition of lead(Pb) thin films by the U V pulsed laser ablation technique,for their further use as photocathode devices in superconducting radio frequency guns.Scanning electron microscopy and atomic force microscopy analyses were performed to study the morphological features of Pb thin films deposited on Si(100) and Nb substrates.The films showed a granular structure with a nearly fully covered surface only for that one deposited on Nb substrata X-ray diffraction measurements indicate the growth of polycrystalline Pb thin films with a preferential orientation along(111) planes.Results of the photoemission performance of Pb thin film deposited on Nb substrate showed a very encouraging average value of quantum efficiency of 6×10~(-5) through a single-photon absorption process,promoting further studies in the realisation of Pb photocathodes by this techniqua  相似文献   
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