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121.
Li-Fu Hu Gudny Eiriksdottir Tatyana Lebedeva Irina Kholodniouk Andrei Alimov Fu Chen Yan Luo Eugene R. Zabarovsky Sigurdur Ingvarsson George Klein Ingemar Ernberg 《Genes, chromosomes & cancer》1996,17(2):118-126
We have examined 17 primary undifferentiated nasopharyngeal carcinoma biopsies for allelic loss on 3p, comparing the findings in tumors with those in normal lymphocyte DNA from the same patients. Ten polymorphic microsatellite markers were used between 3p13 and 3p26. Allelic loss was observed in 12 samples (70%). Two loci were most frequently affected: D3S1067 (3p21.1-14.3) in 60% and D3S1217 (3p14.2-14.1) in 58%. One tumor seemed to have a homozygous deletion at 3p26, detected by the D3S1297 marker. Analysis of the clinical data showed that an increased number of aberrations in 3p was correlated with more advanced tumor stages. Genes Chromosom Cancer 17:118–126 (1996). © 1996 Wiley-Liss, Inc. 相似文献
122.
Jackson R. Taylor Jason G. Wood Evan Mizerak Samuel Hinthorn Julianna Liu Matthew Finn Sarah Gordon Louis Zingas Chengyi Chang Mark A. Klein John M. Denu Vera Gorbunova Andrei Seluanov Jef D. Boeke John M. Sedivy Stephen L. Helfand 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(5)
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124.
Liubov V. Pershina Andrei R. Grabeklis Ludmila N. Isankina Ekaterina V. Skorb Konstantin G. Nikolaev 《RSC advances》2021,11(57):36215
Nowadays, there are several methods for the detection of various bioelements during SARS-CoV-2. Many of them require special equipment, high expenses, and a long time to obtain results. In this study, we aim to use polyelectrolyte multilayers for robust carbon fiber-based potentiometric sensing to determine the ion concentration in human biofluids of COVID-19 patients. The polyethyleneimine/polystyrene sulfonate complex is hygroscopic and has the ability to retain counterions of inorganic salts. This fact makes it possible to create a flexible ionometric system with a pseudo-liquid connection. The formation of the polyethyleneimine/polystyrene sulfonate complex allows for the adhesion of a hydrophobic ion-selective membrane, and creates a Nernst response in a miniature sensor system. This approach discloses the development of miniaturized ion-selective electrodes and their future application to monitor analyte changes as micro and macroelement ions in the human body to identify correlation to SARS-CoV-2. An imbalance in the content of potassium and sodium in urine and blood is directly related to changes in the zinc content in patients with coronavirus. The proposed method for assessing the condition of patients will allow fast determination of the severity of the course of the disease.Supramolecular assemblies based on polyelectrolyte complexes made it possible to create complex interfaces with predictable properties. Polyelectrolyte complexes serve as a pseudo-liquid contact in ion-selective electrodes. 相似文献
125.
Annette Setzer Pablo D. Esquinazi Sergei Buga Milena T. Georgieva Tilo Reinert Tom Venus Irina Estrela-Lopis Andrei Ivashenko Maria Bondarenko Winfried Bhlmann Jan Meijer 《Materials》2022,15(3)
In this work, we demonstrate that cutting diamond crystals with a laser (532 nm wavelength, 0.5 mJ energy, 200 ns pulse duration at 15 kHz) produced a ≲20 nm thick surface layer with magnetic order at room temperature. We measured the magnetic moment of five natural and six CVD diamond crystals of different sizes, nitrogen contents and surface orientations with a SQUID magnetometer. A robust ferromagnetic response at 300 K was observed only for crystals that were cut with the laser along the (100) surface orientation. The magnetic signals were much weaker for the (110) and negligible for the (111) orientations. We attribute the magnetic order to the disordered graphite layer produced by the laser at the diamond surface. The ferromagnetic signal vanished after chemical etching or after moderate temperature annealing. The obtained results indicate that laser treatment of diamond may pave the way to create ferromagnetic spots at its surface. 相似文献
126.
Ioana Mihaela Citu Cosmin Citu Madalin-Marius Margan Marius Craina Radu Neamtu Oana Maria Gorun Bogdan Burlea Felix Bratosin Ovidiu Rosca Mirela Loredana Grigoras Andrei Motoc Daniel Malita Octavian Neagoe Florin Gorun 《Nutrients》2022,14(7)
Magnesium may contribute to the immune response during and after SARS-CoV-2 infection by acting as a cofactor for immunoglobulin production and other processes required for T and B cell activity. Considering magnesium as a recommended dietary supplement during pregnancy and the possible role of magnesium deficiency in COVID-19 and its complications, the current study sought to determine the effect of magnesium and magnesium-containing nutritional supplements on the immune response following SARS-CoV-2 infection in pregnant women, as well as to observe differences in pregnancy outcomes based on the supplements taken during pregnancy. The study followed a cross-sectional design, where patients with a history of SARS-CoV-2 infection during their pregnancy were surveyed for their preferences in nutritional supplementation and their profile compared with existing records from the institutional database. A cohort of 448 pregnant women with COVID-19 during 22 months of the pandemic was assembled, out of which 13.6% took a magnesium-only supplement, and 16.5% supplemented their diet with a combination of calcium, magnesium, and zinc. Around 60% of patients in the no-supplementation group had the SARS-CoV-2 anti-RBD lower than 500 U/mL, compared with 50% in those who took magnesium-based supplements. A quantity of magnesium >450 mg in the taken supplements determined higher levels of antibody titers after COVID-19. Low magnesium dosage (<450 mg) was an independent risk factor for a weak immune response (OR-1.25, p-value = 0.003). The observed findings suggest supplementing the nutritional intake of pregnant women with magnesium-based supplements to determine higher levels of SARS-CoV-2 anti-RBD antibodies, although causality remains unclear. 相似文献
127.
Maher Saqqur MD MPH FRCPC Georgios Tsivgoulis MD Francois Nicoli MD David Skoloudik MD Vijay K. Sharma MD Vincent Larrue MD Jürgen Eggers MD PhD FAHA Fabienne Perren MD Paris Charalampidis PhD Dale Storie PSL Ashfaq Shuaib MD FRCPC FAHA Andrei V. Alexandrov MD RVT 《Journal of neuroimaging》2014,24(3):209-220
128.
129.
R. Snoeck G. Andrei E. De Clercq 《European journal of clinical microbiology & infectious diseases》1996,15(7):574-579
Drug-resistant human Cytomegalovirus (HCMV) strains were selected in human embryonic lung (HEL) fibroblasts under pressure of the (S)-3-hydroxy-2-phosphonylmethoxypropyl (HPMP) derivatives of cytosine (HPMPC) and adenine (HPMPA), the 2-phosphonylmethoxyethyl (PME) derivative of 2,6-diaminopurine (PMEDAP), ganciclovir (GCV), acyclovir (ACV), and foscarnet (PFA). Drug susceptibility profiles of the different drug-resistant (i.e., GCVr, HPMPCr, HPMPAr, PFAr, ACVr, and PMEDAPr) strains were determined in HEL cells. A considerable degree of cross-resistance against GCV, HPMPC, and HPMPA occurred with the GCVr, HPMPCr, and HPMPAr strains. No changes in susceptibility to 9-(2-phosphonylmethoxyethyl)adenine (PMEA), PMEDAP, ACV, or PFA were detected for the HPMPCr, HPMPAr, and GCVr strains when compared to the wild-type virus. On the other hand, a significant degree of cross-resistance was noted with the PMEDAPr, PFAr, and ACVr strains against PMEA, PMEDAP, PFA, and ACV. No differences in susceptibility to HPMPC, HPMPA and GCV were observed for the ACVr, PFAr, and PMEDAPr strains relative to the wild type. The drug susceptibility profiles of the different resistant strains point to a common mechanism of HCMV resistance to PFA and the PME derivatives that is different from the mechanism of HCMV resistance to the HPMP derivatives. 相似文献
130.
G. Andrei R. Snoeck P. Goubau J. Desmyter E. De Clercq 《European journal of clinical microbiology & infectious diseases》1992,11(2):143-151
The following compounds were evaluated for their inhibitory activity against clinical strains of herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) in both primary rabbit kidney (PRK) and HeLa cell cultures: (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine (HPMPA), 9-(2-phosphonylmethoxyethyl)adenine (PMEA), (S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine (HPMPC), (RS)-9-(3-hydroxy-2-phosphonylmethoxypropyl)-2,6-diaminopurine (HPMPDAP), 5-(5-bromothien-2-yl)-2-deoxyuridine (BTDU), 5-(5-chlorothien-2-yl)-2-deoxyuridine (CTDU), 9-(2-deoxy-2-hydroxymethyl--D-erythro-oxetanosyl)guanine (OXT-G), pentosan polysulfate, heparin, dextran sulfate (MW 10,000), acyclovir, 9-(2-hydroxyethoxymethyl)guanine (ACV), (E)-5-(2-bromovinyl)-2-deoxyuridine (BVDU), 1--D-arabinofuranosyl-(E)-5-(2-bromovinyl)-uracil (BVaraU), vidarabine (9--D-arabinofuranosyladenine) (ara-A) and phosphonoformate (PFA). The most potent inhibitors of HSV-1 were (in order of decreasing activity in PRK cells) BVDU, ACV, BVaraU and OXT-G, their mean 50 % inhibitory concentration (IC50) ranging from 0.02 µg/ml to 0.9 µg/ml. Then followed BTDU and CTDU (IC50 1–2 µg/ml), the sulfated polysaccharides (IC50 1.3–5.8 µg/ml), the phosphonylmethoxyalkyl derivatives (IC50 5.6–25 µg/ml), ara-A (IC50 11 µg/ml) and PFA (IC50 38.5 µg/ml). Except for BVDU, BVaraU, BTDU and CTDU, the compounds did not discriminate between HSV-2 and HSV-1. All the compounds studied could be considered specific anti-HSV agents. Their selectivity indexes varied from 3 (PFA) to 6400 (BVDU). 相似文献