The lac repressor protects the lac operator against digestion with deoxyribonuclease. The protected fragment is double-stranded and about 27 base-pairs long. We determined the sequence of RNA transcription copies of this fragment and present a sequence for 24 base pairs. It is: 5'--T G G A A T T G T G A G C G G A T A A C A A T T 3' 3'--A C C T T A A C A C T C G C C T A T T G T T A A 5' The sequence has 2-fold symmetry regions; the two longest are separated by one turn of the DNA double helix.
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http://dx.doi.org/10.1073/pnas.70.12.3581 | DOI Listing |
ACS Appl Mater Interfaces
January 2025
Institute of Translational Medicine, Medical College, Yangzhou University, Yangzhou 225001, China.
The intricacy, diversity, and heterogeneity of cancers make research focus on developing multimodal synergistic therapy strategies. Herein, an oxygen (O) self-feeding peroxisomal lactate oxidase (LOX)-based LOX-Ce6-Mn (LCM) was synthesized using a biomineralization approach, which was used for cascade chemodynamic therapy (CDT)/photodynamic therapy (PDT) combination therapies through dual depletion of lactate (Lac) and reactive oxygen species (ROS) generation. After endocytosis into tumor cells, the endogenous hydrogen peroxide (HO) can be converted to O by the catalase-like (CAT) activity of LCM, which can facilitate the catalytic reaction of LOX to consume more Lac and alleviate tumor hypoxia to enhance the generation of singlet oxygen (O) upon light irradiation.
View Article and Find Full Text PDFFront Med (Lausanne)
January 2025
Department of Cardiovascular Surgery, Xijing Hospital, Air Force Medical University, Xi'an, China.
Background: Acute type A aortic dissection (ATAAD) is a life-threatening condition that often requires total aortic arch replacement (TAR) combined with frozen elephant trunk (FET) implantation. Despite advancements in surgical techniques and preoperative management, postoperative acute kidney injury (AKI) remains a prevalent complication that significantly affects patient prognosis, particularly severe AKI. The aim of this study was to investigate the predictive value of perioperative lactate levels in severe postoperative AKI after TAR.
View Article and Find Full Text PDFNat Commun
January 2025
Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden.
The rate at which transcription factors (TFs) bind their cognate sites has long been assumed to be limited by diffusion, and thus independent of binding site sequence. Here, we systematically test this assumption using cell-to-cell variability in gene expression as a window into the in vivo association and dissociation kinetics of the model transcription factor LacI. Using a stochastic model of the relationship between gene expression variability and binding kinetics, we performed single-cell gene expression measurements to infer association and dissociation rates for a set of 35 different LacI binding sites.
View Article and Find Full Text PDFMicrosyst Nanoeng
January 2025
Department of Systems Design Engineering, University of Waterloo, Waterloo, ON, N2L 3G1, Canada.
This paper presents a novel technique for low-power generation of frequency combs (FC) over a wide frequency range. It leverages modal interactions between electrical and mechanical resonators in electrostatic NEMS operating in air to provide a simple architecture for FC generators. A biased voltage signal drives the electrical resonator at resonance which is set to match an integer submultiple of twice the mechanical resonator's resonance.
View Article and Find Full Text PDFBMC Cardiovasc Disord
January 2025
Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital Fudan University, Shanghai, China.
Background: Unlike non-rheumatic atrial fibrillation (AF), where left atrial thrombus (LAT) is predominantly confined to the left atrial appendage (LAA), a significant proportion of LAT in rheumatic AF occurs within the left atrial cavity (LAC). However, LAC thrombosis in rheumatic AF has not been extensively studied. This study aimed to evaluate the prevalence of LAT and its subtypes and identify potential predictors of LAT.
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