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101.
Paul Thorey Željko Knez Maja Habulin 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2010,85(7):1011-1016
BACKGROUND: The demand for enantiomerically pure molecules is growing continuously and biocatalysis is a powerful technique for their production. In this work, the catalyst was an enzyme combined with its coenzyme, NADP. High pressure technology, a second clean technology, was applied as well. Dense gases are promising solvents for biocatalysis. They have been investigated extensively as reaction media for lipase‐catalysed reactions, but seldom for reactions, catalysed with alcohol dehydrogenases, as in this work. RESULT: The production of optically pure R‐1‐phenylethanol from acetophenone was investigated. The NADP‐dependent alcohol dehydrogenase from Lactobacillus brevis (LBADH) was used as a catalyst. The hydrogenation was performed with isopropanol as a co‐substrate in different conditions: dense propane with LBADH and NADP co‐immobilized on glass beads and in the biphasic system water/dense propane. The obtained R‐1‐phenylethanol was enantiopure. The conversions were up to 90%. Deactivation of LBADH was also measured in these media. CONCLUSION: Protocols were successfully developed for the testing of alcohol dehydrogenase activity in dense gases. Enantioselectivity of LBADH is excellent in those media but it deactivated quickly. An LBADH‐catalysed reaction was performed in a dense gas for the first time. Copyright © 2010 Society of Chemical Industry 相似文献
102.
Milena Todorovic Balint Jelena Jelicic Biljana Mihaljevic Jelena Kostic Bojana Stanic Bela Balint Nadja Pejanovic Bojana Lucic Natasa Tosic Irena Marjanovic Maja Stojiljkovic Teodora Karan-Djurasevic Ognjen Perisic Goran Rakocevic Milos Popovic Sava Raicevic Jelena Bila Darko Antic Bosko Andjelic Sonja Pavlovic 《International journal of molecular sciences》2016,17(5)
The existence of a potential primary central nervous system lymphoma-specific genomic signature that differs from the systemic form of diffuse large B cell lymphoma (DLBCL) has been suggested, but is still controversial. We investigated 19 patients with primary DLBCL of central nervous system (DLBCL CNS) using the TruSeq Amplicon Cancer Panel (TSACP) for 48 cancer-related genes. Next generation sequencing (NGS) analyses have revealed that over 80% of potentially protein-changing mutations were located in eight genes (CTNNB1, PIK3CA, PTEN, ATM, KRAS, PTPN11, TP53 and JAK3), pointing to the potential role of these genes in lymphomagenesis. TP53 was the only gene harboring mutations in all 19 patients. In addition, the presence of mutated TP53 and ATM genes correlated with a higher total number of mutations in other analyzed genes. Furthermore, the presence of mutated ATM correlated with poorer event-free survival (EFS) (p = 0.036). The presence of the mutated SMO gene correlated with earlier disease relapse (p = 0.023), inferior event-free survival (p = 0.011) and overall survival (OS) (p = 0.017), while mutations in the PTEN gene were associated with inferior OS (p = 0.048). Our findings suggest that the TP53 and ATM genes could be involved in the molecular pathophysiology of primary DLBCL CNS, whereas mutations in the PTEN and SMO genes could affect survival regardless of the initial treatment approach. 相似文献
103.
Maja Von?ina Stanislav KoresPrimo? Mrvar Jo?ef Medved 《Journal of Alloys and Compounds》2011,509(27):7349-7355
The effect of Ce addition on the AA A360 (Al-10%Si-0.5%Mg) alloy was investigated using equilibrium thermodynamic calculation, thermal analysis, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The purpose is to study the variations that occur during solidification and precipitation with different Ce additions, as well as their effect on the mechanical properties. The results show that the Ce addition decreases the eutectic (αAl + Mg2Si) temperature. The solidus temperature also decreases with the increasing Ce addition. The precipitation enthalpy determined using DSC decreases with the Ce addition, while precipitation takes place more rapidly and intensively, indicating increased reaction kinetics. The mechanical properties like hardness and tensile strength also increase with the Ce addition. The phase that contributed to the hardness of the investigated alloy was composed of Al, Ce, Mg and Si. 相似文献
104.
Adhesives of aquatic organisms are of high scientific interest with a view to biomimicry. The visualization of their fine-structure,
however, is difficult due to the fragility of the extracellular matrix (ECM). Care must be taken in its preparation for high-resolution
SEM. Relating matrix structures to substrate properties demands a high throughput of samples for reliable comparisons. In
order to acquaint ourselves with a suitable method we found an easy way to manage the critical steps of preparation for SEM.
We show that thin layers of proteinaceous matrix can be satisfactorily prepared by combining freeze-drying and sputtering
in a conventional sputter coater after one-step fixation (2.5% glutaraldehyde). The results were superior to CPD. 相似文献
105.
The aim of this research is to gain an insight into international recognition of the STM (Science, Technology, and Medicine)
Croatian journals measured by citations in SCI-expanded database. The sample for the research was a citation analysis of 142
journals in time span 1975–2001 for papers published in 1975–1998. More than 90% of those journals are not indexed by SCI-expanded.
For the purpose of this research we introduced a new scientometric indicator Normalized number of Citations per 100 Papers (NCP) that allows us direct comparison of the journals from various categories (NCP = 100C/P / IF1989). We chose the year 1989 as a mean value for time span 1975–2001.
By citation analysis we established the influence of errors on recognition of Croatian journals and their articles. Obtained
results show that an article-to-article link is not found for 32% of cited items. The most frequent type of error is journal
title, 37%, which indicates that approximately one third of Croatian journals can not be found when searching by journal title
only.
Some Croatian journals, even not indexed by SCI-expanded, showed relatively high rank in an impact, i.e. their NCP is higher
than 100, and number of citations per paper is higher than 1. 相似文献
106.
This paper describes a hands-off socially assistive therapist robot designed to monitor, assist, encourage, and socially interact
with post-stroke users engaged in rehabilitation exercises. We investigate the role of the robot’s personality in the hands-off
therapy process, focusing on the relationship between the level of extroversion–introversion of the robot and the user. We
also demonstrate a behavior adaptation system capable of adjusting its social interaction parameters (e.g., interaction distances/proxemics,
speed, and vocal content) toward customized post-stroke rehabilitation therapy based on the user’s personality traits and
task performance. Three validation experiment sets are described. The first maps the user’s extroversion–introversion personality
dimension to a spectrum of robot therapy styles that range from challenging to nurturing. The second and the third experiments
adjust the personality matching dynamically to adapt the robot’s therapy styles based on user personality and performance.
The reported results provide first evidence for user preference for personality matching in the assistive domain and demonstrate
how the socially assistive robot’s autonomous behavior adaptation to the user’s personality can result in improved human task
performance.
This work was supported by USC Women in Science and Engineering (WiSE) Program and the Okawa Foundation. 相似文献
107.
Maja Tomic Eda Vrtacnik Bokal Martin Stimpfel 《International journal of molecular sciences》2022,23(7)
This review focuses on recent findings in the preimplantation genetic testing (PGT) of embryos. Different preimplantation genetic tests are presented along with different genetic materials and their analysis. Original material concerning preimplantation genetic testing for aneuploidy (PGT-A) was sourced by searching the PubMed and ScienceDirect databases in October and November 2021. The searches comprised keywords such as ‘preimplantation’, ‘cfDNA’; ‘miRNA’, ‘PGT-A’, ‘niPGT-A’, ‘aneuploidy’, ‘mosaicism’, ‘blastocyst biopsy’, ‘blastocentesis’, ‘blastocoel fluid’, ‘NGS’, ‘FISH’, and ‘aCGH’. Non-invasive PGT-A (niPGT-A) is a novel approach to the genetic analysis of embryos. The premise is that the genetic material in the spent embryo culture media (SECM) corresponds to the genetic material in the embryo cells. The limitations of niPGT-A are a lower quantity and lesser quality of the cell-free genetic material, and its unknown origin. The concordance rate varies when compared to invasive PGT-A. Some authors have also hypothesized that mosaicism and aneuploid cells are preferentially excluded from the embryo during early development. Cell-free genetic material is readily available in the spent embryo culture media, which provides an easier, more economic, and safer extraction of genetic material for analysis. The sampling of the SECM and DNA extraction and amplification must be optimized. The origin of the cell-free media, the percentage of apoptotic events, and the levels of DNA contamination are currently unknown; these topics need to be further investigated. 相似文献
108.
Vesna Marjanovic Radmila Markovic Mirjana Steharnik Silvana Dimitrijevic Aleksandar D. Marinkovic Aleksandra Peric-Grujic Maja olic 《International journal of molecular sciences》2022,23(22)
Highly porous lignin-based microspheres, modified by magnetite nanoparticles, were used for the first time for the removal of selenate anions, Se(VI), from spiked and real water samples. The influence of experimental conditions: selenate concentration, adsorbent dosage and contact time on the adsorption capacity was investigated in a batch experimental mode. The FTIR, XRD, SEM techniques were used to analyze the structural and morphological properties of the native and exhausted adsorbent. The maximum adsorption capacity was found to be 69.9 mg/g for Se(VI) anions at pH 6.46 from the simulated water samples. The modified natural polymer was efficient in Se(VI) removal from the real (potable) water samples, originated from six cities in the Republic of Serbia, with an overage efficacy of 20%. The regeneration capacity of 61% in one cycle of desorption (0.5 M NaOH as desorption solution) of bio-based adsorbent was gained in this investigation. The examined material demonstrated a significant affinity for Se(VI) oxyanion, but a low potential for multi-cycle material application; consequently, the loaded sorbent could be proposed to be used as a Se fertilizer. 相似文献
109.
Jerko tambuk Frano Vu
kovi Sinia Habazin Maja Hani Mislav Novokmet Susanna Nikolaus Florian Tran Stefan Schreiber Andre Franke Philip Rosenstiel Gordan Lauc Konrad Aden Marija Pezer 《International journal of molecular sciences》2022,23(15)
Immunosuppressants and biologicals are widely used therapeutics for various chronic inflammatory diseases (CID). To gain more detailed insight into their downstream effects, we examined their impact on serum immunoglobulin G (IgG) glycosylation. We analyzed IgG subclass-specific fragment crystallizable (Fc) N-glycosylation in patients suffering from various CID using the LC-MS approach. Firstly, we compared IgG Fc N-glycosylation between 128 CID patients and 204 healthy controls. Our results replicated previously observed CID-related decrease in IgG Fc galactosylation (adjusted p-value range 1.70 × 10−2–5.95 × 10−22) and sialylation (adjusted p-value range 1.85 × 10−2–1.71 × 10−18). Secondly, to assess changes in IgG Fc N-glycosylation associated with therapy and remission status, we compared 139 CID patients receiving either azathioprine, infliximab, or vedolizumab therapy. We observed an increase in IgG Fc galactosylation (adjusted p-value range 1.98 × 10−2–1.30 × 10−15) and sialylation (adjusted p-value range 3.28 × 10−6–4.34 × 10−18) during the treatment. Furthermore, patients who reached remission displayed increased Fc galactosylation levels (p-value range 2.25 × 10−2–5.44 × 10−3) in comparison to patients with active disease. In conclusion, the alterations in IgG Fc glycosylation and the fact these changes are even more pronounced in patients who achieved remission, suggest modulation of IgG inflammatory potential associated with CID therapy. 相似文献