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Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science Review 2024年第1期11卷 8-10页

作者： david j.Bottjer department of Earth Sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

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global weirding at mass extinction horizons

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National Science Review 2024年第1期11卷 10-12页

作者： gregory j.Retallack department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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Half a century after their discovery:Structural insights into exonuclease and annealase proteins catalyzing recombineering

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Engineering Microbiology 2024年第1期4卷 39-54页

作者： Lucy j.Fitschen Timothy P.Newing Nikolas P.johnston Charles E.Bell gökhan Tolun School of Chemistry and Molecular Bioscience and Molecular HorizonsUniversity of WollongongWollongongNSWAustralia The ARC Training Centre for Cryo-electron Microscopy of Membrane Proteins University of WollongongWollongongNSWAustralia Faculty of Science University of Technology SydneyUltimoNSW 2007Australia department of Biological Chemistry and Pharmacology The Ohio State University College of MedicineColumbusOH 43210

Recombineering is an essential tool for molecular biologists,allowing for the facile and efficient manipulation of bacterial genomes directly in cells without the need for costly and laborious in vitro manipulations involving restriction *** main workhorses behind recombineering are bacteriophage proteins that promote the single-strand annealing(SSA)homologous recombination pathway to repair double-stranded dNA *** there have been several reviews examining recombineering methods and applications,comparatively few have focused on the mechanisms of the proteins that are the key players in the SSA pathway:a 5′→3′exonuclease and a single-strand annealing protein(SSAP or“annealase”).This review dives into the structures and functions of the two SSA recombination systems that were the first to be developed for recombineering in ***:the RecET system from *** Rac prophage and the𝜆Red system from bacteriophageλ.By comparing the structures of the RecT and Red𝛽annealases,and the RecE and𝜆Exo exonucleases,we provide new insights into how the structures of these proteins dictate their *** the sequence conservation of the𝜆λExo and RecE exonucleases gives more profound insights into their critical functional ***,as recombineering accelerates and evolves in the laboratory,a better understanding of the mechanisms of the proteins behind this powerful technique will drive the development of improved and expanded capabilities in the future.

关键词： Recombineering Redβ λExo RecE RecT Protein structure Annealase Exonuclease

decoding the genetic program of micronucleus formation: linking chromosomal instability to human disease

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2840-2842页

作者： jörg Fahrer division of Food Chemistry and Toxicology Department of ChemistryRPTU Kaiserslautern-Landau67663 KaiserslauternGermany

A recent study by Adams and colleagues published in Nature unveiled more than one hundred genes that are involved in micronucleus formation,1 which is a biomarker for genomic instability and associated with aging,cancer,and other disorders.2 As an outstanding achievement,the authors identified dSCC1(dNA Replication And Sister Chromatid Cohesion 1)as a critical gene protecting against early developmental defects,genomic instability,reduced proliferative capacity,cohesinopathy-related phenotypes,and tumor development in vivo.

关键词： chromosomal linking Replication

In vivo femtosecond laser nanosurgery of the cell wall enabling patch-clamp measurements on filamentous fungi

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Microsystems & Nanoengineering 2024年第2期10卷 251-267页

作者： Tanja Pajić Katarina Stevanović Nataša V.Todorović Aleksandar j.Krmpot Miroslav Živić Svetlana Savić-Šević Steva M.Lević Marina Stanić dejan Pantelić Brana jelenković Mihailo d.Rabasović Institute of Physiology and Biochemistry“Ivan djaja” Faculty of BiologyUniversity of BelgradeStudentski trg 1611158BelgradeSerbia Institute for Biological Research“Siniša Stanković” University of BelgradeNational Institute of the Republic of SerbiaBulevar Despota Stefana 14211000BelgradeSerbia Institute of Physics Belgrade University of BelgradeNational Institute of the Republic of SerbiaPregrevica 11811080BelgradeSerbia University of Belgrade Faculty of AgricultureNemanjina Street 611080BelgradeSerbia Institute for Multidisciplinary Research University of BelgradeKneza Višeslava 111030BelgradeSerbia

Studying the membrane physiology of filamentous fungi is key to understanding their interactions with the environment and crucial for developing new therapeutic strategies for disease-causing ***,their plasma membrane has been inaccessible for a micron-sized patch-clamp pipette for pA current recordings due to the rigid chitinous cell ***,we report the first femtosecond IR laser nanosurgery of the cell wall of the filamentous fungi,which enabled patch-clamp measurements on protoplasts released from hyphae.A reproducible and highly precise(diffraction-limited,submicron resolution)method for obtaining viable released protoplasts was *** release from the nanosurgery-generated incisions in the cell wall was achieved from different regions of the *** plasma membrane of the obtained protoplasts formed tight and high-resistance(gΩ)contacts with the recording *** entire nanosurgical procedure followed by the patch-clamp technique could be completed in less than 1 *** to previous studies using heterologously expressed channels,this technique provides the opportunity to identify new ionic currents and to study the properties of the ion channels in the protoplasts of filamentous fungi in their native environment.

关键词： patch recording laser

Estradiol increases cortical and trabecular bone accrual and bone strength in an adolescent male-to-female mouse model of gender-affirming hormone therapy

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Bone Research 2024年第1期12卷 95-106页

作者： Tian Nie Varun S.Venkatesh Suzanne golub Kathryn S.Stok Haniyeh Hemmatian Reena desai david j.Handelsman jeffrey d.Zajac Mathis grossmann Rachel A.davey department of Medicine Austin HealthUniversity of MelbourneHeidelbergVIC 3084Australia department of Biomedical Engineering University of MelbourneParkvilleVIC 3010Australia ANZAC Research Institute University of Sydney and AndrologyConcord Repatriation General HospitalConcordNSW 2137Australia

The effects of gender-affirming hormone therapy on the skeletal integrity and fracture risk in transitioning adolescent trans girls are *** address this knowledge gap,we developed a mouse model to simulate male-to-female transition in human adolescents in whom puberty is first arrested by using gonadotrophin-releasing hormone analogs with subsequent estradiol *** was suppressed by orchidectomy in male mice at 5 weeks of *** 3 weeks post-surgery,male-to-female mice were treated with a high dose of estradiol(~0.85 mg)by intraperitoneal silastic implantation for 12 *** included intact and orchidectomized males at 3 weeks post-surgery,vehicle-treated intact males,intact females and orchidectomized males at 12 weeks *** to male controls,orchidectomized males exhibited decreased peak bone mass accrual and a decreased maximal force the bone could withstand prior to *** treatment in orchidectomized male-to-female mice compared to mice in all control groups was associated with an increased cortical thickness in the mid-diaphysis,while the periosteal circumference increased to a level that was intermediate between intact male and female controls,resulting in increased maximal force and *** trabecular bone,estradiol treatment increased newly formed trabeculae arising from the growth plate as well as mineralizing surface/bone surface and bone formation rate,consistent with the anabolic action of estradiol on osteoblast *** data support the concept that skeletal integrity can be preserved and that long-term fractures may be prevented in trans girls treated with gnRHa and a sufficiently high dose of *** study is needed to identify an optimal dose of estradiol that protects the bone without adverse side effects.

关键词： treatment treatment strength

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Necrotic enteritis and antibiotic-free production of broiler chickens:Challenges in testing and using alternative products

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Animal Nutrition 2024年第1期16卷 288-298页

作者： Robert j.Moore School of Science RMIT University

The global trend towards raising broiler chickens without the use of in-feed antibiotics(IFAs) means that there is an ongoing need to develop alternative treatments capable of delivering the benefits that IFAs previously provided. IFAs supported the productivity performance of chickens and played a key role in maintaining their health. Necrotic enteritis(NE) is an important disease of broilers that affects health,productivity, and welfare, and was previously well controlled by IFAs. However, with the reduction in IFA use, NE is resurgent in some countries. Vaccines and various feed additives, including pre-, pro-, and postbiotics, phytobiotics, fatty acids, and phage therapies have been introduced as alternative methods of NE control. While some of these feed additives have specific activity against the NE pathogen, Clostridium perfringens, most have the more general goal of reinforcing gut health. Extensive reviews of the effects of many of these feed additives on gut health have been published recently. Hence, rather than cover previously well reviewed areas of research this review focuses on the challenges and pitfalls in undertaking experimental assessment of alternative NE treatments and translating laboratory research to real world commercial production settings. The review is based on the author's particular experience,reading, thoughts, and analysis of the available information and inevitably presents a particular understanding that is likely to be at odds with others thinking on these issues. It is put forward to stimulate thinking and discussion on the issues covered.

关键词： Necrotic enteritis Clostridium perfringens Vaccines Feed additive Farm management

Are hydrides under high-pressure-high-temperature superconductors?

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National Science Review 2024年第7期11卷 9-12页

作者： j.E.Hirsch department of Physics University of California

Contrary to the current consensus, I argue that the existing evidence for high-temperature superconductivity in hydrides under high pressure is not compelling. I suggest that the focus of the field should urgently shift to establish unequivocally experimentally whether or not superconductivity in pressurized hydrides exists, instead of continuing to search for new materials that might show elusive signals of unproven superconductivity at ever higher temperatures. The implications of a negative finding for the theoretical understanding of superconductivity are discussed.

关键词： Hydrides

Hepatic angiotensin-converting enzyme 2 expression in metabolic dysfunction-associated steatotic liver disease and in patients with fatal COVId-19

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World journal of gastroenterology 2024年第31期30卷 3705-3716页

作者： Angus K jacobs Steven d Morley Kay Samuel Katie Morgan Lyndsey Boswell Timothy j Kendall david A dorward jonathan A Fallowfield Peter C Hayes john N Plevris Hepatology Laboratory University of EdinburghEdinburgh EH164SBUnited Kingdom Scottish National Blood Transfusion Service Jack Copland CentreEdinburgh EH144BEUnited Kingdom Institute for Regeneration and Repair University of EdinburghEdinburgh EH164UUUnited Kingdom Edinburgh Pathology University of EdinburghEdinburgh EH164SBUnited Kingdom

BACKgROUNd Metabolic dysfunction-associated steatotic liver disease(MASLd),characterised by hepatic lipid accumulation,causes inflammation and oxidative stress accompanied by cell damage and *** injury(LI)is also frequently reported in patients hospitalised with coronavirus disease 2019(COVId-19),while preexisting MASLd increases the risk of LI and the development of COVId-19-associated *** of injury at the cellular level remain unclear,but it may be significant that severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)which causes COVId-19,uses angiotensin-converting expression enzyme 2(ACE2),a key regulator of the‘anti-inflammatory’arm of the renin-angiotensin system,for viral attachment and host cell *** To determine if hepatic ACE2 levels are altered during progression of MASLd and in patients who died with severe *** ACE2 protein levels and localisation,and histological fibrosis and lipid droplet accumulation as markers of MASLd were determined in formalin-fixed liver tissue sections across the MASLd pathological spectrum(isolated hepatocellular steatosis,metabolic dysfunction-associated steatohepatitis(MASH)+/-fibrosis,end-stage cirrhosis)and in post-mortem tissues from patients who had died with severe COVId-19,using ACE2 immunohistochemistry and haematoxylin and eosin and picrosirius red staining of total collagen and lipid droplet areas,followed by quantification using machine learning-based image pixel *** ACE2 staining is primarily intracellular and concentrated in the cytoplasm of centrilobular hepatocytes and apical membranes of bile duct ***,ACE2 protein levels are elevated in non-fibrotic MASH compared to healthy controls but not in the progression to MASH with fibrosis and in ***2 protein levels and histological fibrosis are not associated,but ACE2 and liver lipid droplet content are significantly correlated across the MASLd *** A

关键词： Metabolic dysfunction-associated steatotic liver disease Angiotensin-converting enzyme 2 Immunohistochemistry COVId-19 COVId-19-associated cholangiopathy