986 research outputs found
An ionic organic–inorganic hybrid: tetrakis[bis(1,10-phenanthroline)copper(I)] dodecatungstophosphate(V)
Single crystals of the title polyoxometallate-based organic–inorganic hybrid, [Cu(C12H8N2)2]4[SiW12O40], were grown under hydrothermal conditions. The discrete [SiW12O40]4− anions are of the Keggin type and are packed in a slightly distorted orthorhombic F-centred mode, with the complex [CuI(phen)2]+ cations (phen is 1,10-phenanthroline) located in the voids of this arrangement. The four independent CuI cations are situated in the centres of more or less distorted tetrahedra made up of N atoms from the phen ligands. The anions and cations are linked together via weak hydrogen-bonding interactions, forming an extended three-dimensional network. Additional stabilization is achieved via π–π interactions between different phen molecules of adjacent [CuI(phen)2]+ cations with shortest distances between 3.416 and 3.499 Å
1,2,4,5-Tetraphenyl-1H-imidazole
The asymmetric unit of the title compound, C27H20N2, contains two independent molecules, A and B. In both molecules, the N atom in the 1-position and the C atom in the 5-position are statistically disordered [as 0.571 (8):0.429 (8) in A and 0.736 (9):0.264 (9) in B]. The phenyl rings in the 1-, 2-, 4- and 5-positions in A are twisted from the central imidazole ring by 84.3 (2), 21.6 (2), 21.5 (2) and 75.7 (2)°, respectively. The corresponding dihedral angles in B are 85.5 (2), 3.8 (2), 2.4 (2) and 81.7 (2)°, respectively
Construction of a cDNA library and preliminary analysis of the expressed sequence tags of the earthworm Eisenia fetida (Savigny, 1826)
Earthworms are useful indicator organisms of soil health and Eisenia fetida have been extensively used as test organisms in ecotoxicological studies. In order to gain insight into the gene expression profiles associated with physiological functions of earthworms, a full‑length enriched cDNA library of the Eisenia fetida genome was successfully constructed using Switching Mechanism at 5\u27End of RNA Template technology. Construction of a cDNA library and analysis of Expressed Sequence Tags (ESTs) are efficient approaches for collecting genomic information and identifying genes important for a given biological process. Furthermore, analysis of the expression abundance of ESTs was performed with the aim of providing genetic and transcriptomic information on the development and regenerative process of earthworms. Phrep and Crossmatch were used to process EST data and a total of 1,140 high‑quality EST sequences were determined by sequencing random cDNA clones from the library. Clustering analysis of sequences revealed a total of 593 unique sequences including 225 contiguous and 368 singleton sequences. Basic Local Alignment Search Tool analysis against the Kyoto Encyclopedia of Genes and Genomes database resulted in 593 significant hits (P‑value \u3c1x10‑8), of which 168 were annotated through Gene Ontology analysis. The STRING database was used to determine relationships among the 168 ESTs, identifying associated genes involved in protein‑protein interactions and gene expression regulation. Based on nucleic acid and protein sequence homology, the mutual relationships between 287 genes could be obtained, which identified a portion of the ESTs as known genes. The present study reports on the construction of a high‑quality cDNA library representative of adult earthworms, on a preliminary analysis of ESTs and on a putative functional analysis of ESTs. The present study is expected to enhance our understanding of the molecular basis underlying the biological development of earthworms
Distribution of pediatric keratoconus by different age and gender groups
PurposeTo evaluate the distribution of pediatric keratoconus patients and the disease severity based on different age and gender groups in China.Materials and methodsA total of 446 keratoconus eyes in 266 pediatric patients from January 2019 to January 2022 were included in the cross-sectional study. The clinical findings and severity of keratoconus were recorded and Kruskal–Wallis test, chi-squared test, and Cochran-Mantel-Haenszel (CMH) test were used to compare the parameters between different gender and age groups.ResultsThe male/female ratio was 353/93 (3.8:1), and the median age was 16 years (range: 6–17 years). Male patients were statistically younger than female patients (P = 0.041). The male/female ratio decreased with age (P for trend = 0.011). The distribution of the topographic keratoconus classification (TKC) stage was significantly different between gender and age groups (all P < 0.05). Male patients had a higher ratio of advanced keratoconus eyes (TKC ≥ 3) than female patients (P < 0.001), and CMH analysis indicated that being a male was a risk factor for advanced keratoconus after controlling for age (odds ratio: 2.581, P < 0.001).ConclusionMale keratoconus patients were younger, with a higher ratio of advanced keratoconus than female patients in the Chinese pediatric patients evaluated. Multicenter studies with larger sample sizes are necessary in the future
Efficacy and safety of piperacillin–tazobactam compared with meropenem in treating complicated urinary tract infections including acute pyelonephritis due to extended-spectrum β-lactamase-producing Enterobacteriaceae
IntroductionExtended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae pose a huge threat to human health, especially in the context of complicated urinary tract infections (cUTIs). Carbapenems and piperacillin–tazobactam (PTZ) are two antimicrobial agents commonly used to treat cUTIs.MethodsA monocentric retrospective cohort study focused on the treatment of cUTIs in adults was conducted from January 2019 to November 2021. Patients with a positive urine culture strain yielding ≥ 103 colony-forming units per milliliter (CFU/mL), and sensitive to PTZ and carbapenems, were included. The primary endpoint was clinical success after antibiotic therapy. The secondary endpoint included rehospitalization and 90-day recurrence of cUTIs caused by ESBL-producing Enterobacteriaceae.ResultsOf the 195 patients included in this study, 110 were treated with PTZ while 85 were administered meropenem. The rate of clinical cure was similar between the PTZ and meropenem groups (80% vs. 78.8%, p = 0.84). However, the PTZ group had a lower duration of total antibiotic use (6 vs. 9; p < 0.01), lower duration of effective antibiotic therapy (6 vs. 8; p < 0.01), and lower duration of hospitalization (16 vs. 22; p < 0.01).DiscussionIn terms of adverse events, the safety of PTZ was higher than that of meropenem in the treatment of cUTIs
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