Density functional theory (DFT) calculations were performed at the B3LYP level with a 6-311++G(d,p) basis set to systematically explore the geometrical multiplicity and binding strength for complexes formed by Li(+), Na(+), and K(+) with cytidine and 2'-deoxycytidine. All computational studies indicate that the metal ion affinity (MIA) decreases from Li(+) to Na(+) and K(+) for cytosine nucleosides. For example, for cytidine the affinity for the above metal ions are 79.5, 55.2, and 41.8 and for 2'-deoxycytidine, 82.8, 57.4, and 42.2 kcal/mol, respectively. It is also interesting to mention that linear correlations between calculated MIA values and the atomic numbers (Z) of the above metal ions were found. The influence of metal cationization on the coordination modes and the strength of the N-glycosidic bond in cytosine nucleosides have been studied. In all cases, the N1-C1' bond distance changes upon introducing a positive charge in the nucleosides. It has been found that metal binding significantly changes the values of the phase angle of pseudorotation P in the sugar unit of these nucleosides. With respect to the sugar ring, metal binding changes the values of the glycosyl torsion angle and sugar ring conformation. The present calculations in the gas phase provide the first clues on the intrinsic chemistry of these systems and may be of value for studies of the influence of metal cations on the conformational behavior and function of nucleic acids.
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http://dx.doi.org/10.1016/j.carres.2009.02.007 | DOI Listing |
APMIS
January 2025
Laboratory Sciences Research Center, Golestan University of Medical Sciences, Gorgan, Iran.
Colistin is a last-resort treatment for multidrug-resistant Gram-negative bacterial infections, particularly in critically ill patients. Nevertheless, it remains a major threat to public health. We assessed the proportion of colistin-resistant Gram-negative isolates from intensive care unit (ICU) infections in different years, areas, pathogens, and antimicrobial susceptibility tests (AST).
View Article and Find Full Text PDFAnal Methods
December 2024
Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou, 730070, China.
It is widely known that homocysteine (Hcy) is associated with the pathogenesis of many clinical diseases, and its quantitative detection can help early treatment of related diseases. The selection of materials with excellent properties is important for the construction of electrochemical sensing platforms and quantitative detection of Hcy. In this study, two nanocomposites, Au nanoparticles/hollow carbon spheres (AuNPs@HCS) and Au nanoparticles/solid carbon spheres (AuNPs@SCS), were prepared first.
View Article and Find Full Text PDFAdv Healthc Mater
December 2024
State Key Laboratory of Separation Membranes and Membrane Processes & Key Laboratory of Hollow Fiber Membrane Materials and Membrane Processes (MOE) & Tianjin Key Laboratory of Hollow Fiber Membrane Materials and Processes, School of Materials Science and Engineering, Tiangong University, Tianjin, 300387, P. R. China.
Fusobacterium nucleatum (Fn), as an intestinal pathogenic bacterium, is closely related to the occurrence, progression, and limited therapeutic efficacy of colorectal cancer (CRC). The presence of Fn within CRC communities induces an inflammatory and immunosuppressive microenvironment while promoting new vessel formation. Therefore, developing novel methods to efficiently eliminate Fn and enhance the therapeutic outcomes against Fn-associated CRC is of great significance.
View Article and Find Full Text PDFSpine J
December 2024
Department of Spine Surgery, The Third Affiliated Hospital, Sun Yat-sen University, No.600 Tianhe Road, Tianhe District, Guangzhou, 510630, Guangdong, China; Guangdong Provincial Center for Quality Control of Minimally Invasive Spine Surgery, No. 600 Tianhe Road, Guangzhou, 510630, China; Guangdong Provincial Center for Engineering and Technology Research of Minimally Invasive Spine Surgery, No. 600 Tianhe Road, Guangzhou, 510630, China. Electronic address:
Background Context: Spinal cord injury (SCI) causes neural circuit interruption and permanent functional damage. Magnetic stimulation in humans with SCI aims to engage residual neural networks to improve neurological functional, but the detailed mechanism remains unknown.
Purpose: This study evaluates functional recovery and neural circuitry improvements in rodent with double-target (brain and spinal cord) magnetic stimulation (DTMS) treatment and explores the effect of DTMS on the modulation of glial cells in vivo and in vitro.
Radiol Case Rep
February 2025
Affiliated Hainan Hospital of Hainan Medical University (Hainan General Hospital ), NO. 19, XiuHua ST, XiuYing District, Haikou, Hainan, 570311, PR China.
Gliosarcoma (GS) is a rare subtype of glioblastoma multiforme, characterized by a shorter clinical course and poorer prognosis compared to glioblastoma. Here, we report the case of a 50-year-old male patient who presented with episodic loss of consciousness and left-sided limb weakness for one month. MRI revealed a complex neoplastic lesion in the right fronto-parietal region.
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