The similar conformations and interaction modes of Ac-DL-Leu-NMe2 and Ac-delta-Leu-NMe2 molecules in the solid state allow the comparison of their geometrical parameters. The most evident variations are essentially restricted to the alpha, beta-unsaturated side-chain which adopts the Z-disposition. The dimensions of the peptide backbone are much less sensitive to alpha, beta-unsaturation, with a small shortening by 0.04 A and 0.02 A of the N--C alpha and C alpha--C' bonds, respectively, and an increase by 6 degrees of the N--C alpha--C' bond angle. The ethylenic and amide groups in the delta-Leu derivative are far from coplanarity, and a significant electronic conjugation of the pi-orbital is likely to be rejected.
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http://dx.doi.org/10.1111/j.1399-3011.1992.tb00431.x | DOI Listing |
Background: The photothermal sensitivity of tobacco refers to how tobacco plants respond to variations in the photothermal conditions of their growth environment. The degree of this sensitivity is crucial for determining the optimal planting regions for specific varieties, as well as for improving the quality and yield of tobacco leaves. However, the precise mechanisms underlying the development of photothermal sensitivity in tobacco remain unclear.
View Article and Find Full Text PDFBMC Genomics
January 2025
Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Avenue 1095, Wuhan, Hubei, 430030, China.
Background: Left-right (LR) asymmetry disorders present a complex etiology, with genetic factors emerging as a primary contributor. This study aims to explore the genetic underpinnings of chromosomal variants and individual genes in fetuses afflicted with prenatal LR asymmetry disorder.
Methods: Through a retrospective analysis conducted between 2020 and 2023 at Tongji Hospital, Huazhong University of Science and Technology, genetic outcomes of LR asymmetric disorder were scrutinized utilizing copy number variation sequencing (CNV-seq) and whole exome sequencing (WES) methodologies.
Surg Endosc
January 2025
Department of Surgery, Campus Charité Mitte Campus Virchow-Klinikum, Charité Universitätsmedizin Berlin, Berlin, Germany.
Background: Minimally Invasive Esophagectomy (MIE) is a complex surgical procedure that has become a cornerstone in the management of esophageal cancer. This study aims to delineate the learning curve associated with MIE and its impact on patient outcomes.
Methods: A retrospective analysis was conducted on 191 patients who underwent MIE between 2015 and 2022.
Hand, foot and mouth disease (HFMD) is a major public health issue in Hubei Province; however, research on the direct and indirect effects of factors affecting HFMD is limited. This study employed structural equation modeling (SEM) and geographically weighted regression (GWR) to investigate the various impacts and spatial variations in the factors influencing the HFMD epidemic in Hubei Province from 2016 to 2018. The results indicated that (1) with respect to the direct effects, the number of primary school students had the greatest positive direct effect on the number of HFMD cases, with a coefficient of 0.
View Article and Find Full Text PDFEcotoxicol Environ Saf
January 2025
National Human Diseases Animal Model Resource Center, National Center of Technology Innovation for animal model, State Key Laboratory of Respiratory Health and Multimorbidity, NHC Key Laboratory of Comparative Medicine, Beijing Key Laboratory for Animal Models of Emerging and Reemerging Infectious Diseases, Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, Institute of Laboratory Animal Science, CAMS & PUMC, Beijing, China. Electronic address:
Background: Previous studies showed airborne bacteria affect pneumonia incidence, but specific impacts of bacterial communities on Klebsiella pneumoniae infection were unknown.
Methods: Five different ratios of bacterial community structures were randomly generated. Mice were divided into control, artificial bacterial community exposure, and corresponding Klebsiella pneumoniae challenge groups.
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