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81.
Madalena C. Pinto Margarida C. Quaresma Iris A. L. Silva Violeta Railean Sofia S. Ramalho Margarida D. Amaral 《International journal of molecular sciences》2021,22(23)
SLC26A9, a constitutively active Cl− transporter, has gained interest over the past years as a relevant disease modifier in several respiratory disorders including Cystic Fibrosis (CF), asthma, and non-CF bronchiectasis. SLC26A9 contributes to epithelial Cl− secretion, thus preventing mucus obstruction under inflammatory conditions. Additionally, SLC26A9 was identified as a CF gene modifier, and its polymorphisms were shown to correlate with the response to drugs modulating CFTR, the defective protein in CF. Here, we aimed to investigate the relationship between SLC26A9 and CFTR, and its role in CF pathogenesis. Our data show that SLC26A9 expression contributes to enhanced CFTR expression and function. While knocking-down SLC26A9 in human bronchial cells leads to lower wt- and F508del-CFTR expression, function, and response to CFTR correctors, the opposite occurs upon its overexpression, highlighting SLC26A9 relevance for CF. Accordingly, F508del-CFTR rescue by the most efficient correctors available is further enhanced by increasing SLC26A9 expression. Interestingly, SLC26A9 overexpression does not increase the PM expression of non-F508del CFTR traffic mutants, namely those unresponsive to corrector drugs. Altogether, our data indicate that SLC26A9 stabilizes CFTR at the ER level and that the efficacy of CFTR modulator drugs may be further enhanced by increasing its expression. 相似文献
82.
Iris Reiners Harald Grger Jürgen Martens 《Advanced Synthesis \u0026amp; Catalysis》1997,339(1):541-546
The enantioselective reduction of N,S-heterocyclic imines, namely thiazolines 1a, b and 2H-1,4-benzothiazine 1c , via three different reduction methods is reported. The influence of reaction parameters, substituents, and the type of heterocycle was investigated. Reduction of the prochiral imines led to the corresponding amine derivatives 2, 10, 12 and 14 . The best result was obtained by stoichiometric enantioselective reduction of 1c with 44% ee. 相似文献
83.
Detecting Deception in Children: Event Familiarity Affects Criterion-Based Content Analysis Ratings.
84.
Iris Reychav Merrill Warkentin Martin Ndicu 《Journal of Computer Information Systems》2016,56(4):280-287
Teachers play a key role in adoption of technologies for classroom use. This study surveyed teachers regarding their intention to use tablet technology to interact with students and other teachers through smart school websites technology. The Unified Theory of Acceptance and Use of Technology (UTAUT) served as the theoretical framework for this study, which was then augmented with context-specific determinants of adoption that captured teachers’ perceptions of the effects of technology on interactions with students and peers. The results showed no resistance among teachers with regard to trying different ways of working with tablets to achieve better learning, unlike other studies using the UTAUT constructs that have found negative reactions to implementing new technologies in the workplace. This is a crucial finding, since teacher appraisals affect the ways in which this technology can be employed to foster learning through technology facilitated interactions. 相似文献
85.
Iris Ribitsch Andrea Bileck Alexander D. Aldoshin Maciej M. Kadua Rupert L. Mayer Monika Egerbacher Simone Gabner Ulrike Auer Sinan Gültekin Johann Huber David P. Kreil Christopher Gerner Florien Jenner 《International journal of molecular sciences》2021,22(11)
Tendinopathies are painful, disabling conditions that afflict 25% of the adult human population. Filling an unmet need for realistic large-animal models, we here present an ovine model of tendon injury for the comparative study of adult scarring repair and fetal regeneration. Complete regeneration of the fetal tendon within 28 days is demonstrated, while adult tendon defects remained macroscopically and histologically evident five months post-injury. In addition to a comprehensive histological assessment, proteome analyses of secretomes were performed. Confirming histological data, a specific and pronounced inflammation accompanied by activation of neutrophils in adult tendon defects was observed, corroborated by the significant up-regulation of pro-inflammatory factors, neutrophil attracting chemokines, the release of potentially tissue-damaging antimicrobial and extracellular matrix-degrading enzymes, and a response to oxidative stress. In contrast, secreted proteins of injured fetal tendons included proteins initiating the resolution of inflammation or promoting functional extracellular matrix production. These results demonstrate the power and relevance of our novel ovine fetal tendon regeneration model, which thus promises to accelerate research in the field. First insights from the model already support our molecular understanding of successful fetal tendon healing processes and may guide improved therapeutic strategies. 相似文献
86.
Antje Güttler Yvonne Eiselt Anne Funtan Andreas Thiel Marina Petrenko Jacqueline Keßler Iris Thondorf Reinhard Paschke Dirk Vordermark Matthias Bache 《International journal of molecular sciences》2021,22(16)
Hypoxia-regulated protein carbonic anhydrase IX (CA IX) is up-regulated in different tumor entities and correlated with poor prognosis in breast cancer patients. Due to the radio- and chemotherapy resistance of solid hypoxic tumors, derivatives of betulinic acid (BA), a natural compound with anticancer properties, seem to be promising to benefit these cancer patients. We synthesized new betulin sulfonamides and determined their cytotoxicity in different breast cancer cell lines. Additionally, we investigated their effects on clonogenic survival, cell death, extracellular pH, HIF-1α, CA IX and CA XII protein levels and radiosensitivity. Our study revealed that cytotoxicity increased after treatment with the betulin sulfonamides compared to BA or their precursors, especially in triple-negative breast cancer (TNBC) cells. CA IX activity as well as CA IX and CA XII protein levels were reduced by the betulin sulfonamides. We observed elevated inhibitory efficiency against protumorigenic processes such as proliferation and clonogenic survival and the promotion of cell death and radiosensitivity compared to the precursor derivatives. In particular, TNBC cells showed benefit from the addition of sulfonamides onto BA and revealed that betulin sulfonamides are promising compounds to treat more aggressive breast cancers, or are at the same level against less aggressive breast cancer cells. 相似文献
87.
88.
Venkataraman L Klare JE Tam IW Nuckolls C Hybertsen MS Steigerwald ML 《Nano letters》2006,6(3):458-462
We measure the conductance of amine-terminated molecules by breaking Au point contacts in a molecular solution at room temperature. We find that the variability of the observed conductance for the diamine molecule-Au junctions is much less than the variability for diisonitrile- and dithiol-Au junctions. This narrow distribution enables unambiguous conductance measurements of single molecules. For an alkane diamine series with 2-8 carbon atoms in the hydrocarbon chain, our results show a systematic trend in the conductance from which we extract a tunneling decay constant of 0.91 +/- 0.03 per methylene group. We hypothesize that the diamine link binds preferentially to undercoordinated Au atoms in the junction. This is supported by density functional theory-based calculations that show the amine binding to a gold adatom with sufficient angular flexibility for easy junction formation but well-defined electronic coupling of the N lone pair to the Au. Therefore, the amine linkage leads to well-defined conductance measurements of a single molecule junction in a statistical study. 相似文献
89.
I Bergmair W Hackl M Losurdo C Helgert G Isic M Rohn MM Jakovljevic T Mueller M Giangregorio EB Kley T Fromherz R Gajic T Pertsch G Bruno M Muehlberger 《Nanotechnology》2012,23(33):335301
In this work we demonstrate for the first time the micro-?and nanostructuring of graphene by means of UV-nanoimprint lithography. Exfoliated graphene on SiO(2) substrates, as well as graphene deposited by chemical vapor deposition (CVD) on polycrystalline nickel and copper, and transferred CVD graphene on dielectric substrates, were used to demonstrate that our technique is suitable for large-area patterning (2?×?2?cm(2)) of graphene on various types of substrates. The demonstrated fabrication procedure of micrometer as well as nanometer-sized graphene structures with feature sizes down to 20?nm by a wafer-scale process opens up an avenue for the low-cost and high-throughput manufacturing of graphene-based optical and electronic applications. The processed graphene films show electron mobilities of up to 4.6?×?10(3)?cm(2)?V (-1)?s(-1), which confirms them to exhibit state-of-the-art electronic quality with respect to the current literature. 相似文献
90.
Flavonoids are bioactive compounds found in plants. Studies indicate consumption of food containing these compounds may reduce the incidences of cancer and cardiovascular diseases. In broccoli, the flavonoids are present at variable concentrations and so far have mainly been determined using high performance liquid chromatography (HPLC). This paper describes a rapid capillary electrophoresis method, involving large volume sample stacking (LVSS), suitable for the analysis of flavonoids in broccoli. Following acid hydrolysis, the two key flavonoids (kaempferol and quercetin) in a broccoli extract were concentrated on-line by LVSS prior to separation by capillary zone electrophoresis (CZE). Using an optimised method, the extract was injected for 50 s into a 50 μm (internal diameter) × 85 cm (total length) capillary followed by stacking/matrix removal at −5 kV for 83 s. The two analytes were then separated in less than 8 min by CZE using a 10 mM sodium borate buffer (pH 8.40) and a separation voltage of +30 kV at 30 °C. A linear relationship in the range 1–20 ppm was observed for the method (r2 = 0.9991–0.9995) with detection limits of 0.9 and 0.6 mg/kg of broccoli for kaempferol and quercetin, respectively. This method demonstrated good repeatability for the standard and extract with relative standard deviations of less than 5% for both peak area and migration time measured over five different days (n = 5). The method was successfully applied to quantitatively determine kaempferol and quercetin contents in a commercial broccoli sample as 11.8 and 14.6 mg/kg fresh weight, respectively. This result was validated by HPLC analysis and is within the ranges reported in the literature. 相似文献