How RAG1/2 evolved from ancestral transposases to initiate V(D)J recombination without transposition.

The RAG1/2 recombinase, which initiates V(D)J recombination in jawed vertebrates, evolved from RNaseH-like transposases such as Transib and ProtoRAG . However, its post-cleavage transposase activity is strictly suppressed. Previous structural studies have focused only on the conserved core domains of RAG1/2, leaving the regulatory mechanisms of the non-core regions unclear.

Use of Fluid Gelatin in Lumbar Spinal Stenosis Undergoing Unilateral Biportal Endoscopic: A Prospective, Randomized Controlled Trial.

Objectives: In patients with lumbar spinal stenosis (LSS) undergoing unilateral biportal endoscopic unilateral laminotomy for bilateral decompression (UBE-ULBD), damage to the epidural venous plexus often leads to bleeding, increasing the risk of surgical complications. Surgiflo Hemostatic Matrix (SHM) is a gelatin extracted from porcine skin, used for intraoperative hemostasis. This study aims to evaluate the effectiveness and safety of using SHM during UBE-ULBD surgery.

Effects of Fluid Gelatin for Lumbar Spinal Stenosis Undergoing Lumbar Endoscopic Bilateral Decompression: A Prospective, Randomized Controlled Trial.

Objectives: In patients with lumbar spinal stenosis (LSS), prolonged compression of the epidural venous plexus heightens the risk of bleeding and hematoma during minimally invasive surgery. While absorbable fluid gelatin, an animal protein-based hemostatic agent, is available, its effectiveness in lumbar endoscopic unilateral laminotomy with bilateral decompression (LE-ULBD) remains debated. Our research aims to conduct a prospective randomized controlled trial to investigate the effectiveness and safety of this hemostatic material in patients undergoing LE-ULBD for LSS.

A study of liquidity cross-chain models based on convex optimization.

Blockchain after several years of hustle, bustle, precipitation, and sublimation, with the landing application step by step towards maturity and development, gradually spawned the outreach needs of interacting with other applications. At this stage, only the mobility cross-chain interoperability technology is the infrastructure system that can perfectly solve such needs. To achieve a cross-chain system that defines and realizes user-free liquidity interoperability according to the cross-chain environment and cross-chain requirements, this paper designs a convex optimization-based liquidity contract pair cross-chain model.

A study of blockchain-based liquidity cross-chain model.

Blockchain cross-chaining is about interconnectivity and interoperability between chains and involves both physical to virtual digital aspects and cross-chaining between digital networks. During the process, the liquidity transfer of information or assets can increase the use of items with other chains, so it is worth noting that the enhancement of cross-chain liquidity is of great practical importance to cross-chain technology. In this model, Layerzero is used as the primary secure cross-chain facility to build a full-chain identity by unifying NFT-distributed autonomous cross-chain identity IDs; applying super-contract pairs to enhance cross-chain liquidity; and initiating a dynamic transaction node creditworthiness model to increase the security of the cross-chain model and its risk management.

Cryo-EM structures of membrane-bound dynamin in a post-hydrolysis state primed for membrane fission.

Dynamin assembles as a helical polymer at the neck of budding endocytic vesicles, constricting the underlying membrane as it progresses through the GTPase cycle to sever vesicles from the plasma membrane. Although atomic models of the dynamin helical polymer bound to guanosine triphosphate (GTP) analogs define earlier stages of membrane constriction, there are no atomic models of the assembled state post-GTP hydrolysis. Here, we used cryo-EM methods to determine atomic structures of the dynamin helical polymer assembled on lipid tubules, akin to necks of budding endocytic vesicles, in a guanosine diphosphate (GDP)-bound, super-constricted state.

HIV-1 Integrase Assembles Multiple Species of Stable Synaptic Complex Intasomes That Are Active for Concerted DNA Integration In vitro.

Retroviral DNA integration is mediated by nucleoprotein complexes (intasomes) in which a pair of viral DNA ends are bridged by a multimer of integrase (IN). Most of the high-resolution structures of HIV-1 intasomes are based on an HIV-1 IN with an Sso7d protein domain fused to the N-terminus. Sso7d-IN aggregates much less than wild-type IN and has been critical for structural studies of HIV-1 intasomes.

Tandem MutSβ binding to long extruded DNA trinucleotide repeats underpins pathogenic expansions.

Expansion of trinucleotide repeats causes Huntington's disease, Fragile X syndrome and over twenty other monogenic disorders. How mismatch repair protein MutSβ and large repeats of CNG (N=A, T, C or G) cooperate to drive the expansion is poorly understood. Contrary to expectations, we find that MutSβ prefers to bind the stem of an extruded (CNG) hairpin rather than the hairpin end or hairpin-duplex junction.

Detailed characterization of particle emissions due to thermal failure of batteries with different cathodes.

Sufficient levels of thermal, electrical, mechanical, or electrochemical abuse can cause thermal runaway in lithium-ion batteries, leading to the release of electrolyte vapor, combustible gas mixtures, and high-temperature particles. Particle emissions due to thermal failure of batteries may cause serious pollution of the atmosphere, water sources, and soil as well as enter the human biological chain through crops, posing a potential threat to human health. Furthermore, high-temperature particle emissions may ignite the flammable gas mixtures produced during the thermal runaway process, resulting in combustion and explosions.

Lesion recognition by XPC, TFIIH and XPA in DNA excision repair.

Nucleotide excision repair removes DNA lesions caused by ultraviolet light, cisplatin-like compounds and bulky adducts. After initial recognition by XPC in global genome repair or a stalled RNA polymerase in transcription-coupled repair, damaged DNA is transferred to the seven-subunit TFIIH core complex (Core7) for verification and dual incisions by the XPF and XPG nucleases. Structures capturing lesion recognition by the yeast XPC homologue Rad4 and TFIIH in transcription initiation or DNA repair have been separately reported.

Prediction of Male Coronary Artery Bypass Grafting Outcomes Using Body Surface Area Weighted Left Ventricular End-diastolic Diameter: Multicenter Retrospective Cohort Study.

Background: The presence of a high left ventricular end-diastolic diameter (LVEDD) has been linked to a less favorable outcome in patients undergoing coronary artery bypass grafting (CABG) procedures. However, by taking into consideration the reference of left ventricular size and volume measurements relative to the patient's body surface area (BSA), it has been suggested that the accuracy of the predicting outcomes may be improved.

Objective: We propose that BSA weighted LVEDD (bLVEDD) is a more accurate predictor of outcomes in patients undergoing CABG compared to simply using LVEDD alone.

Predicting the Glycemic Index of Biscuits Using Static In Vitro Digestion Protocols.

In vitro digestion methods that can accurately predict the estimated GI (eGI) values of complex carbohydrate foods, including biscuits, are worth exploring. In the current study, standard commercial biscuits with varied clinical GI values between 9~30 were digested using both the INFOGEST and single-enzyme digestion protocols. The digestion kinetic parameters were acquired through mathematical fitting by mathematical kinetics models.

Effect of the Current on the Fire Characteristics of Overloaded Polyvinyl Chloride Copper Wires.

In this study, the fire behavior variation of unenergized polyvinyl chloride (PVC) copper wires subjected to overload with different currents was investigated by a cone calorimeter. Overload currents were selected from 1 times safe-rated current () to 3.5 times to obtain tested sample wires.

lncRNA HAGLR modulates myocardial ischemia-reperfusion injury in mice through regulating miR-133a-3p/MAPK1 axis.

Acute myocardial infarction is one of the leading causes of morbidity worldwide, but the underlying mechanism responsible for myocardial ischemia-reperfusion (I/R) injury remains elusive. lncRNA plays roles in inflammatory response, cell apoptosis and regulation of myocardial ischemia. However, whether lncRNA HAGLR could regulate myocardial I/R injury and the molecular mechanism need to be further investigated.

Addition of amino acids modulates the in vitro digestibility of corn starch.

The addition of amino acids (AAs) including glycine (Gly), lysine (Lys) and glutamic acid (Glu) with different concentrations on starch morphological, physicochemical and in vitro digestion properties were studied. While AAs showed no effects on neither morphology nor crystalline characters, they all significantly influenced the starch relative crystallinity and swelling capacity in an order of Glu > Lys > Gly. For all samples, both fastly- and slowly- digestible starch fractions (S and S) were observed.

Increasing contributions of airborne route in SARS-CoV-2 omicron variant transmission compared with the ancestral strain.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant has become the dominant lineage worldwide. Experimental studies have shown that SARS-CoV-2 Omicron variant is more stable on various environmental surfaces than the ancestral strains of SARS-CoV-2. However, the influences on the role of the contact route in SARS-CoV-2 transmission are still unknown.

Comprehensive bioinformation analysis of differentially expressed genes in recurrent pregnancy loss.

Recurrent pregnancy loss (RPL) occurs frequently, and its causes are complex. The aetiology of nearly 50% of RPL cases is still unknown. This study aimed to ascertain differentially expressed genes (DEGs) and pathways by comprehensive bioinformatics analysis.

Autophosphorylation transforms DNA-PK from protecting to processing DNA ends.

The DNA-dependent protein kinase (DNA-PK) initially protects broken DNA ends but then promotes their processing during non-homologous end joining (NHEJ). Before ligation by NHEJ, DNA hairpin ends generated during V(D)J recombination must be opened by the Artemis nuclease, together with autophosphorylated DNA-PK. Structures of DNA-PK bound to DNA before and after phosphorylation, and in complex with Artemis and a DNA hairpin, reveal an essential functional switch.

No-Touch Versus Conventional Vein Harvesting Techniques at 12 Months After Coronary Artery Bypass Grafting Surgery: Multicenter Randomized, Controlled Trial.

Background: Vein graft occlusion is deemed a major challenge in coronary artery bypass grafting. Previous studies implied that the no-touch technique for vein graft harvesting could reduce occlusion rate compared with the conventional approach; however, evidence on the clinical benefit and generalizability of the no-touch technique is scare.

Methods: From April 2017 to June 2019, we randomly assigned 2655 patients undergoing coronary artery bypass grafting at 7 hospitals in a 1:1 ratio to receive no-touch technique or conventional approach for vein harvesting.

The large bat Helitron DNA transposase forms a compact monomeric assembly that buries and protects its covalently bound 5'-transposon end.

Helitrons are widespread eukaryotic DNA transposons that have significantly contributed to genome variability and evolution, in part because of their distinctive, replicative rolling-circle mechanism, which often mobilizes adjacent genes. Although most eukaryotic transposases form oligomers and use RNase H-like domains to break and rejoin double-stranded DNA (dsDNA), Helitron transposases contain a single-stranded DNA (ssDNA)-specific HUH endonuclease domain. Here, we report the cryo-electron microscopy structure of a Helitron transposase bound to the 5'-transposon end, providing insight into its multidomain architecture and function.

Static and dynamic failure mechanisms of circular granite under the condition of water-heat cycles.

Based on the engineering environment where rocks surrounding wellbores in energy storage areas are influenced by high temperature, cool and hot water, thermal stress etc. in the exploitation of hydrothermally geothermal energy, the experimental study on mechanical properties of ring granite under the static and dynamic loads in the water-heat condition was performed. The experimental results showed that when the ring granite was influenced by the inner diameters, heating temperatures, curing temperatures and heat recovery cycle times, the impact load-strain curves were nonlinear.

Structure of an activated DNA-PK and its implications for NHEJ.

DNA-dependent protein kinase (DNA-PK), like all phosphatidylinositol 3-kinase-related kinases (PIKKs), is composed of conserved FAT and kinase domains (FATKINs) along with solenoid structures made of HEAT repeats. These kinases are activated in response to cellular stress signals, but the mechanisms governing activation and regulation remain unresolved. For DNA-PK, all existing structures represent inactive states with resolution limited to 4.

Study on the dynamic characteristics of rock surrounding a wellbore in energy storage areas during deep geothermal energy mining.

Based on the engineering background in which the rock surrounding a wellbore is affected by a thermal shock, impact disturbances from drilling vibration, cyclic heat extraction and high temperature during hydrothermal geothermal energy mining, the environmental conditions in the shaft wall rock are simulated by means of high temperature, cooling, immersing granite in water with different curing temperatures and applying impact loads. Additionally, an experimental study on the mechanical characteristics of circular granite specimens under radial impact loads and in the heat treatment and water curing conditions is carried out. The results show that the inner diameters of the rings, heating temperatures, curing water temperatures and cycle heating times are less affected than other parameters by the impact load-strain curves of circular granite, which can generally be divided into three sections, i.

A comparative analysis on thermal runaway behavior of Li (NiCoMn) O battery with different nickel contents at cell and module level.

The problem of thermal runaway (TR) propagation challenges the safety design of battery packs, because it aggravates the thermal hazards to accidents. There are many unsolved scientific questions in understanding the mechanisms of TR and its propagation behavior for large format lithium-ion batteries (LIBs). LiNiCoMnO(NCM) is considered as one of the most promising cathode materials for lithium-ion batteries LIBs, given its higher energy design and lower cost.

A Peptide Derived from Lens Epithelium-Derived Growth Factor Stimulates HIV-1 DNA Integration and Facilitates Intasome Structural Studies.

The low solubility and aggregation properties of HIV-1 integrase (IN) are major obstacles for biochemical and structural studies. The lens epithelium-derived growth factor (LEDGF) is a cellular factor that binds IN and tethers preintegration complexes to chromatin before integration. The LEDGF also stimulates HIV-1 IN DNA strand transfer activity and improves its solubility in vitro.