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1.
Aging (Albany NY) ; 162024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38656880

RESUMEN

AIM: In 2019, to examine the functions of METTL3 in liver and underlying mechanisms, we generated mice with hepatocyte-specific METTL3 homozygous knockout (METTL3Δhep) by simultaneously crossing METTL3fl/fl mice with Alb-iCre mice (GPT) or Alb-Cre mice (JAX), respectively. In this study, we explored the potential reasons why hepatocyte-specific METTL3 homozygous disruption by Alb-iCre mice (GPT), but not by Alb-Cre mice (JAX), resulted in acute liver failure (ALF) and then postnatal lethality. MAIN METHODS: Mice with hepatocyte-specific METTL3 knockout were generated by simultaneously crossing METTL3fl/fl mice with Alb-iCre mice (GPT; Strain No. T003814) purchased from the GemPharmatech Co., Ltd., (Nanjing, China) or with Alb-Cre mice (JAX; Strain No. 003574) obtained from The Jackson Laboratory, followed by combined-phenotype analysis. The publicly available RNA-sequencing data deposited in the NCBI Gene Expression Omnibus (GEO) database under the accession No.: GSE198512 (postnatal lethality), GSE197800 (postnatal survival) and GSE176113 (postnatal survival) were mined to explore the potential reasons why hepatocyte-specific METTL3 homozygous deletion by Alb-iCre mice (GPT), but not by Alb-Cre mice (JAX), leads to ALF and then postnatal lethality. KEY FINDINGS: Firstly, we observed that hepatocyte-specific METTL3 homozygous deficiency by Alb-iCre mice (GPT) or by Alb-Cre mice (JAX) caused liver injury, abnormal lipid accumulation and apoptosis. Secondly, we are surprised to find that hepatocyte-specific METTL3 homozygous deletion by Alb-iCre mice (GPT), but not by Alb-Cre mice (JAX), led to ALF and then postnatal lethality. Our findings clearly demonstrated that METTL3Δhep mice (GPT), which are about to die, exhibited the severe destruction of liver histological structure, suggesting that METTL3Δhep mice (GPT) nearly lose normal liver function, which subsequently contributes to ALF, followed by postnatal lethality. Finally, we unexpectedly found that as the compensatory growth responses of hepatocytes to liver injury induced by METTL3Δhep (GPT), the proliferation of METTL3Δhep hepatocytes (GPT), unlike METTL3Δhep hepatocytes (JAX), was not evidenced by the significant increase of Ki67-positive hepatocytes, not accompanied by upregulation of cell-cycle-related genes. Moreover, GO analysis revealed that upregulated genes in METTL3Δhep livers (GPT), unlike METTL3Δhep livers (JAX), are not functionally enriched in terms associated with cell cycle, cell division, mitosis, microtubule cytoskeleton organization, spindle organization, chromatin segregation and organization, and nuclear division, consistent with the loss of compensatory proliferation of METTL3Δhep hepatocytes (GPT) observed in vivo. Thus, obviously, the loss of the compensatory growth capacity of METTL3Δhep hepatocytes (GPT) in response to liver injury might contribute to, at least partially, ALF and subsequently postnatal lethality of METTL3Δhep mice (GPT). SIGNIFICANCE: These findings from this study and other labs provide strong evidence that these phenotypes (i.e., ALF and postnatal lethality) of METTL3Δhep mice (GPT) might be not the real functions of METTL3, and closely related with Alb-iCre mice (GPT), suggesting that we should remind researchers to use Alb-iCre mice (GPT) with caution to knockout gene in hepatocytes in vivo.

2.
Nature ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38658763

RESUMEN

Replacement of liquid electrolytes with polymer gel electrolytes is recognized as a general and effective way of solving safety problems and achieving high flexibility in wearable batteries1-6. However, the poor interface between polymer gel electrolyte and electrode, caused by insufficient wetting, produces much poorer electrochemical properties, especially during the deformation of the battery7-9. Here we report a strategy for designing channel structures in electrodes to incorporate polymer gel electrolytes and to form intimate and stable interfaces for high-performance wearable batteries. As a demonstration, multiple electrode fibres were rotated together to form aligned channels, while the surface of each electrode fibre was designed with networked channels. The monomer solution was effectively infiltrated first along the aligned channels and then into the networked channels. The monomers were then polymerized to produce a gel electrolyte and form intimate and stable interfaces with the electrodes. The resulting fibre lithium-ion battery (FLB) showed high electrochemical performances (for example, an energy density of about 128 Wh kg-1). This strategy also enabled the production of FLBs with a high rate of 3,600 m h-1 per winding unit. The continuous FLBs were woven into a 50 cm × 30 cm textile to provide an output capacity of 2,975 mAh. The FLB textiles worked safely under extreme conditions, such as temperatures of -40 °C and 80 °C and a vacuum of -0.08 MPa. The FLBs show promise for applications in firefighting and space exploration.

3.
bioRxiv ; 2024 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-38659924

RESUMEN

Current treatments targeting individual protein quality control have limited efficacy in alleviating proteinopathies, highlighting the prerequisite for a common upstream druggable target capable of global proteostasis modulation. Building on our prior research establishing nuclear speckles as pivotal organelles responsible for global proteostasis transcriptional control, we aim to alleviate proteinopathies through nuclear speckle rejuvenation. We identified pyrvinium pamoate as a small-molecule nuclear speckle rejuvenator that enhances protein quality control while suppressing YAP1 signaling via decreasing the surface tension of nuclear speckle condensates through interaction with the intrinsically disordered region of nuclear speckle scaffold protein SON. In pre-clinical models, pyrvinium pamoate reduced tauopathy and alleviated retina degeneration by promoting autophagy and ubiquitin-proteasome system. Aberrant nuclear speckle morphology, reduced protein quality control and increased YAP1 activity were also observed in human tauopathies. Our study uncovers novel therapeutic targets for tackling protein misfolding disorders within an expanded proteostasis framework encompassing nuclear speckles and YAP1.

4.
Small ; : e2400570, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38600895

RESUMEN

Lithium (Li) metal batteries are deemed as promising next-generation power solutions but are hindered by the uncontrolled dendrite growth and infinite volume change of Li anodes. The extensively studied 3D scaffolds as solutions generally lead to undesired "top-growth" of Li due to their high electrical conductivity and the lack of ion-transporting pathways. Here, by reducing electrical conductivity and increasing the ionic conductivity of the scaffold, the deposition spot of Li to the bottom of the scaffold can be regulated, thus resulting in a safe bottom-up plating mode of the Li and dendrite-free Li deposition. The resulting symmetrical cells with these scaffolds, despite with a limited pre-plated Li capacity of 5 mAh cm-2, exhibit ultra-stable Li plating/stripping for over 1 year (11 000 h) at a high current density of 3 mA cm-2 and a high areal capacity of 3 mAh cm-2. Moreover, the full cells with these scaffolds further demonstrate high cycling stability under challenging conditions, including high cathode loading of 21.6 mg cm-2, low negative-to-positive ratio of 1.6, and limited electrolyte-to-capacity ratio of 4.2 g Ah-1.

5.
Antimicrob Agents Chemother ; 68(4): e0134623, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38426743

RESUMEN

We evaluated the in vitro activity of meropenem-vaborbactam plus aztreonam (MEV-ATM) against 140 metallo-ß-lactamase (MBL)-producing Klebsiella pneumoniae isolates. Among them, 25 isolates (17.9%) displayed minimum inhibitory concentrations (MIC) ≥ 8 µg/mL, while 112 (80.0%) had MIC ≤ 2 µg/mL. Genomic analysis and subsequent gene cloning experiments revealed OmpK36 134-135GD-insertion and increased carbapenemase gene (blaNDM-1 and blaOXA-48-like) copy numbers are the main factors responsible for MEV-ATM non-susceptibility. Notably, MEV-ATM is actively against aztreonam-avibactam-resistant mutants due to CMY-16 mutations.


Asunto(s)
Antibacterianos , Aztreonam , Ácidos Borónicos , Meropenem/farmacología , Aztreonam/farmacología , Antibacterianos/farmacología , Klebsiella pneumoniae/genética , beta-Lactamasas/genética , Combinación de Medicamentos , Pruebas de Sensibilidad Microbiana , Compuestos de Azabiciclo/farmacología
6.
J Clin Nurs ; 33(6): 2019-2029, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38439181

RESUMEN

OBJECTIVES: To systematically evaluate the efficacy of auricular acupressure on lung function, sleep quality and quality of life in chronic obstructive pulmonary disease patients. BACKGROUND: Auricular acupressure has been increasingly used in chronic obstructive pulmonary disease patients, such as lung function and sleep quality, but the efficacy has not yet been unified. DESIGN: A meta-analysis of randomised controlled trials. METHODS: Randomised controlled trials comparing auricular acupressure intervention with non-auricular acupressure intervention in chronic obstructive pulmonary disease patients were included. We searched English databases and Chinese databases from the inception to 26 December 2022. The risk of bias was assessed by the Cochrane risk of bias tool. The PRISMA statement was used to report a meta-analysis. RESULTS: A total of 12 randomised controlled trials with 987 chronic obstructive pulmonary disease patients were included. The meta-analysis showed that auricular acupressure had significant differences in improving lung function, including FEV1 (MD = 0.29, 95% CI: 0.21 to 0.37, p < .0001), FVC (MD = 0.24, 95% CI: 0.14 to 0.34, p < .0001) and FEV1/FVC (MD = 4.70, 95% CI: 3.63 to 5.78, p < .0001). There was also a positive effect on sleep quality (MD = -0.71, 95% CI: -0.89 to -0.53, p < .0001) and quality of life (MD = -3.20, 95% CI: -3.92 to -2.49, p < .0001). CONCLUSIONS: The results indicated auricular acupressure had a positive efficacy in chronic obstructive pulmonary disease patients to improve lung function, sleep quality and quality of life, but these results should be treated with caution due to the low quality of included studies. Future researchers need to conduct more high-quality randomised controlled trials to provide a solid basis to demonstrate the efficacy of auricular acupressure in chronic obstructive pulmonary disease patients. RELEVANT TO CLINICAL PRACTICE: Auricular acupressure has the advantages of being non-invasive, convenient and without significant side effects. This review suggested auricular acupressure could be considered a non-pharmacological intervention for patients. Clinical nurses can teach chronic obstructive pulmonary disease patients to perform auricular acupressure to help self-manage complications. PATIENT OR PUBLIC CONTRIBUTION: No Patient or Public Contribution.


Asunto(s)
Acupresión , Enfermedad Pulmonar Obstructiva Crónica , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Enfermedad Pulmonar Obstructiva Crónica/terapia , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Acupresión/métodos , Pruebas de Función Respiratoria , Calidad del Sueño
7.
Nano Lett ; 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38525903

RESUMEN

The c-axis piezoresistivity is a fundamental and important parameter of graphite, but its value near zero pressure has not been well determined. Herein, a new method for studying the c-axis piezoresistivity of van der Waals materials near zero pressure is developed on the basis of in situ scanning electron microscopy and finite element simulation. The c-axis piezoresistivity of microscale highly oriented pyrolytic graphite (HOPG) is found to show a large value of 5.68 × 10-5 kPa-1 near zero pressure and decreases by 2 orders of magnitude to the established value of ∼10-7 kPa-1 when the pressure increases to 200 MPa. By modulating the serial tunneling barrier model on the basis of the stacking faults, we describe the c-axis electrical transport of HOPG under compression. The large c-axis piezoresistivity near zero pressure and its large decrease in magnitude with pressure are attributed to the rapid stiffening of the electromechanical properties under compression.

8.
BMC Gastroenterol ; 24(1): 103, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38481133

RESUMEN

BACKGROUND: Doctors are at high risk of developing hemorrhoidal disease (HD), but it is unclear whether doctors are aware of this risk. The OASIS (dOctors AS patIentS) study was performed to examine the prevalence, awareness, diagnosis, and treatment of HD among doctors in big cities in China. METHODS: An online survey consisting of a structured questionnaire was carried out among doctors in grade-A tertiary hospitals in 29 provinces across China from August to October 2020. RESULTS: A total of 1227 questionnaire responses were collected. HD prevalence was 56.8%, with a significant difference between internists and surgeons (P = 0.01). 15.6% of doctors with HD didn't have serious concerns about the recurrence and severity of HD. 91.5% of doctors adopted general treatments, and 83.0% considered oral medications only when topical medications were ineffective. Among the oral medications, Micronized Purified Flavonoid Fraction (MPFF) was most effective based on the scores from three important parameters, but only 17% of doctors received MPFF. CONCLUSIONS: Doctors are at higher risk of developing HD with a high prevalence among Chinese doctors, but they are not fully aware or not concerned about HD. There is a deficiency in treatment recommendations and clinical management of HD even for doctors, including late initiation and inadequate oral drug therapy. Therefore, awareness and standardized treatment of HD should be improved among Chinese doctors, as well as in the general population.


Asunto(s)
Hemorroides , Humanos , Hemorroides/terapia , Hemorroides/tratamiento farmacológico , Centros de Atención Terciaria , Ciudades , Encuestas y Cuestionarios , Internet , China/epidemiología
9.
Infect Genet Evol ; 119: 105581, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38432594

RESUMEN

Alveolar echinococcosis (AE), caused by Echinococcus multilocularis, is an important zoonotic disease. Yili Prefecture in Xinjiang is endemic for AE, however the molecular variability of E. multilocularis in this region is poorly understood. In this study, 127 samples were used for haplotypes analysis, including 79 tissues from humans, 43 liver tissues from small rodents, and 5 fecal samples from dogs. Genetic variability in E. multilocularis was studied using complete sequences of the mitochondrial (mt) genes of cytochrome b (cob), NADH dehydrogenase subunit 2 (nad2), and cytochrome c oxidase subunit 1 (cox1), using a total of 3558 bp per sample. The Asia haplotype 2 (A2) was the dominant haplotype, with 72.15% (57/79) prevalence in humans, 2.33% (1/43) in small rodents, and 80.00% (4/5) in dogs, followed by A5, the second most common haplotype, which infected 27.91% (12/43) small rodents. Haplotype network analysis showed that all haplotypes clustered together with the Asian group. Pairwise fixation index (FST) values showed lower level of genetic differentiation between different regions within the country. Compared with the sequences of E. multilocularis from North America and Europe, all concatenated sequences isolated from Yili Prefecture were highly differentiated and formed a single population. The A2 haplotype, analyzed using the cob, nad2, and cox1 genes of E. multilocularis, is the predominant variant in humans and dogs in Yili Prefecture.


Asunto(s)
Equinococosis , Echinococcus multilocularis , Humanos , Perros , Animales , Echinococcus multilocularis/genética , Haplotipos , Equinococosis/epidemiología , Equinococosis/veterinaria , Zoonosis , Roedores , Citocromos b/genética
10.
Water Res ; 253: 121222, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38335841

RESUMEN

The emergence and transmission of antibiotic resistance genes (ARGs) through plasmid-mediated conjugation has become a significant worldwide public health threat. Biofilms are widely recognized as the primary reservoirs for ARGs, providing favorable conditions for horizontal gene transfer. Quorum sensing (QS) plays a critical role in bacterial biofilm formation, which further influences the spread of bacterial resistance. In this study, we examined the effects of vanillin, a QS inhibitor (QSI), at subinhibitory concentrations (sub-MICs) ranging from 0 - 0.1 g/L, on the transfer of ARGs between Escherichia coli and Pseudomonas aeruginosa. Our findings indicated that vanillin at sub-MICs inhibited the conjugative transfer frequency of the RP4 plasmid. This inhibition was supported by the downregulation of plasmid transfer genes. The suppression of conjugation can mainly be attributed to the inhibition of biofilm formation, the synthesis of extracellular polymeric substances (EPS), and the secretion of virulence factors, all of which are regulated by the bacterial QS system. On the other hand, the levels of ROS and cell membrane permeability were not primary explanations for this phenomenon. Furthermore, vanillin also reduced the conjugative transfer frequency of ARGs in wastewater effluent, providing a potential approach to alleviate bacterial resistance in water environments. These findings underscore the regulatory role of QSI in controlling ARGs transfer and have significant implications for manipulating the dissemination of bacterial resistance in the environment.


Asunto(s)
Antibacterianos , Benzaldehídos , Percepción de Quorum , Antibacterianos/farmacología , Genes Bacterianos , Farmacorresistencia Microbiana/genética , Bacterias/genética , Escherichia coli , Plásmidos , Transferencia de Gen Horizontal
11.
mSphere ; 9(3): e0009524, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38411120

RESUMEN

Genetic editing is a powerful tool for functional characterization of genes in various organisms. With its simplicity and specificity, the CRISPR-Cas9 technology has become a popular editing tool, which introduces site-specific DNA double-strand breaks (DSBs), and then leverages the endogenous repair pathway for DSB repair via homology-directed repair (HDR) or the more error-prone non-homologous end joining (NHEJ) pathways. However, in the Plasmodium parasites, the lack of a typical NHEJ pathway selects for DSB repair through the HDR pathway when a homologous DNA template is available. The AT-rich nature of the Plasmodium genome exacerbates this drawback by making it difficult to clone longer homologous repair DNA templates. To circumvent these challenges, we adopted the hybrid catalytically inactive Cas9 (dCas9)-microbial single-stranded annealing proteins (SSAP) editor to the Plasmodium genome. In Plasmodium yoelii, we demonstrated the use of the dCas9-SSAP, as the cleavage-free gene editor, by targeted gene deletion and gene tagging, even using shorter homologous DNA templates. This dCas9-SSAP method with a shorter DNA template, which did not require DSBs, independent of HDR and NHEJ, would be a great addition to the existing genetic toolbox and could be deployed for the functional characterization of genes in Plasmodium, contributing to improving the ability of the malaria research community in characterizing more than half of genes with unknown functions.IMPORTANCEMalaria caused by Plasmodium parasites infection remains a serious threat to human health, with an estimated 249 million malaria cases and 608,000 deaths worldwide in 2022, according to the latest report from the World Health Organization (WHO). Here, we demonstrated the use of dCas9-single-stranded annealing protein, as the cleavage-free gene editor in Plasmodium yoelii, by targeted deletion and gene tagging, even using shorter homologous DNA templates. This method with a shorter DNA template, which did not require DSBs, independent of HDR and NHEJ, showing the potential significance in greatly improving our ability to elucidate gene functions, would contribute to assisting the malaria research community in deciphering more than half of genes with unknown functions to identify new drug and vaccine targets.


Asunto(s)
Malaria , Plasmodium yoelii , Humanos , Edición Génica , Plasmodium yoelii/genética , Sistemas CRISPR-Cas , ADN
12.
Exp Eye Res ; 240: 109826, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38340947

RESUMEN

Retinitis pigmentosa (RP) is an inherited retinal disorder characterized by the degeneration of photoreceptors. RhoP23H/+ mice, which carry a Pro23His mutation in the RHODOPSIN (Rho) gene, are one of the most studied animal models for RP. However, except for the photoreceptors, other retinal neural cells have not been fully investigated in this model. Here, we record the temporal changes of the retina by optical coherence tomography (OCT) imaging of the RhoP23H/+ mice, from early to mid-phase of retinal degeneration. Based on thickness analysis, we identified a natural retinal thickness adaption in wild-type mice during early adulthood and observed morphological compensation of the inner retina layer to photoreceptor degeneration in the RhoP23H/+ mice, primarily on the inner nuclear layer (INL). RhoP23H/+ mice findings were further validated via: histology showing the negative correlation of INL and ONL thicknesses; as well as electroretinogram (ERG) showing an increased b-wave to a-wave ratio. These results unravel the sequential morphologic events in this model and suggest a better understanding of retinal degeneration of RP for future studies.


Asunto(s)
Degeneración Retiniana , Retinitis Pigmentosa , Ratones , Animales , Degeneración Retiniana/diagnóstico , Degeneración Retiniana/genética , Degeneración Retiniana/patología , Rodopsina/genética , Retina/patología , Retinitis Pigmentosa/genética , Retinitis Pigmentosa/patología , Electrorretinografía , Modelos Animales de Enfermedad
13.
Nature ; 628(8006): 57-61, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38354833

RESUMEN

Early JWST observations have uncovered a population of red sources that might represent a previously overlooked phase of supermassive black hole growth1-3. One of the most intriguing examples is an extremely red, point-like object that was found to be triply imaged by the strong lensing cluster Abell 2744 (ref. 4). Here we present deep JWST/NIRSpec observations of this object, Abell2744-QSO1. The spectroscopy confirms that the three images are of the same object, and that it is a highly reddened (AV ≃ 3) broad emission line active galactic nucleus at a redshift of zspec = 7.0451 ± 0.0005. From the width of Hß (full width at half-maximum = 2,800 ± 250 km s-1), we derive a black hole mass of M BH = 4 - 1 + 2 × 1 0 7 M ⊙ . We infer a very high ratio of black-hole-to-galaxy mass of at least 3%, an order of magnitude more than that seen in local galaxies5 and possibly as high as 100%. The lack of strong metal lines in the spectrum together with the high bolometric luminosity (Lbol = (1.1 ± 0.3) × 1045 erg s-1) indicate that we are seeing the black hole in a phase of rapid growth, accreting at 30% of the Eddington limit. The rapid growth and high black-hole-to-galaxy mass ratio of Abell2744-QSO1 suggest that it may represent the missing link between black hole seeds6 and one of the first luminous quasars7.

14.
Nat Commun ; 15(1): 1838, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38418810

RESUMEN

Plastic crystals as barocaloric materials exhibit the large entropy change rivalling freon, however, the limited pressure-sensitivity and large hysteresis of phase transition hinder the colossal barocaloric effect accomplished reversibly at low pressure. Here we report reversible colossal barocaloric effect at low pressure in two-dimensional van-der-Waals alkylammonium halides. Via introducing long carbon chains in ammonium halide plastic crystals, two-dimensional structure forms in (CH3-(CH2)n-1)2NH2X (X: halogen element) with weak interlayer van-der-Waals force, which dictates interlayer expansion as large as 13% and consequently volume change as much as 12% during phase transition. Such anisotropic expansion provides sufficient space for carbon chains to undergo dramatic conformation disordering, which induces colossal entropy change with large pressure-sensitivity and small hysteresis. The record reversible colossal barocaloric effect with entropy change ΔSr ~ 400 J kg-1 K-1 at 0.08 GPa and adiabatic temperature change ΔTr ~ 11 K at 0.1 GPa highlights the design of novel barocaloric materials by engineering the dimensionality of plastic crystals.

15.
Nature ; 626(8001): 975-978, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38418911

RESUMEN

The identification of sources driving cosmic reionization, a major phase transition from neutral hydrogen to ionized plasma around 600-800 Myr after the Big Bang1-3, has been a matter of debate4. Some models suggest that high ionizing emissivity and escape fractions (fesc) from quasars support their role in driving cosmic reionization5,6. Others propose that the high fesc values from bright galaxies generate sufficient ionizing radiation to drive this process7. Finally, a few studies suggest that the number density of faint galaxies, when combined with a stellar-mass-dependent model of ionizing efficiency and fesc, can effectively dominate cosmic reionization8,9. However, so far, comprehensive spectroscopic studies of low-mass galaxies have not been done because of their extreme faintness. Here we report an analysis of eight ultra-faint galaxies (in a very small field) during the epoch of reionization with absolute magnitudes between MUV ≈ -17 mag and -15 mag (down to 0.005L⋆ (refs. 10,11)). We find that faint galaxies during the first thousand million years of the Universe produce ionizing photons with log[ξion (Hz erg-1)] = 25.80 ± 0.14, a factor of 4 higher than commonly assumed values12. If this field is representative of the large-scale distribution of faint galaxies, the rate of ionizing photons exceeds that needed for reionization, even for escape fractions of the order of 5%.

16.
Curr Med Chem ; 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38347784

RESUMEN

Antioxidant research has recently become a popular topic. Medicinal plants are important sources of novel active compounds. Diarylheptanoids, a typical family of secondary plant metabolites, are of great interest owing to their extensive spectrum of biological activities. They possess a unique 1,7-diphenylmethane structural skeleton. Thus, this review summarizes the natural linear or macrocyclic diarylheptanoids with antioxidant activity in the last two decades. In addition, the relationships between the structural characteristics of natural diarylheptanoids and their antioxidant capacity were also discussed. All the available data highlight the potential of natural diarylheptanoids as novel antioxidants.

17.
Nature ; 626(7998): 313-318, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38326591

RESUMEN

Calcium-oxygen (Ca-O2) batteries can theoretically afford high capacity by the reduction of O2 to calcium oxide compounds (CaOx) at low cost1-5. Yet, a rechargeable Ca-O2 battery that operates at room temperature has not been achieved because the CaOx/O2 chemistry typically involves inert discharge products and few electrolytes can accommodate both a highly reductive Ca metal anode and O2. Here we report a Ca-O2 battery that is rechargeable for 700 cycles at room temperature. Our battery relies on a highly reversible two-electron redox to form chemically reactive calcium peroxide (CaO2) as the discharge product. Using a durable ionic liquid-based electrolyte, this two-electron reaction is enabled by the facilitated Ca plating-stripping in the Ca metal anode at room temperature and improved CaO2/O2 redox in the air cathode. We show the proposed Ca-O2 battery is stable in air and can be made into flexible fibres that are weaved into textile batteries for next-generation wearable systems.

18.
Photodiagnosis Photodyn Ther ; 46: 103974, 2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38373471

RESUMEN

OBJECTIVE: The study aimed to compare the clinical efficacy and safety of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) and surgery in treating recurrent cervical high-grade squamous intraepithelial lesions (HSIL) after surgery due to precancerous lesions. METHODS: A total of 41 patients with recurrent cervical HSIL after surgery for precancerous lesions were studied retrospectively. Patients underwent ALA-PDT or surgery and were followed up at 3, 6, 9 and 12 months and then every six months after that. Clinical data were collected and the efficacy and safety of the two treatment methods were compared. RESULTS: Of the 41 patients with recurrent cervical HSIL after conization, 15 cases received ALA-PDT and 26 received surgery. At the six-month follow-up, the lesions' complete remission (CR) rate was 93.33 % in ALA-PDT group and 88.46 % in the surgery group. The human papillomavirus (HPV) clearance rates were 66.67 % and 73.08 %, respectively. No significant differences concerning the lesions' CR rate and the HPV clearance rate were observed between the two groups (P>0.05). At the twelve-month follow-up, the HPV clearance rates were 80.00 % and 91.67 %. No significant differences concerning the HPV clearance rate were observed between the two groups (P>0.05). In the surgery group, the HPV clearance rate and the lesions' CR rate were lower in patients over 45 years of age (25.00% vs. 81.82 %, P = 0.031; 50.00% vs. 95.45 %, P = 0.052). During the follow-up, there was no significant difference in the recurrence rate between the two groups (P>0.05). In addition, none of the patients progressed. In women treated with ALA-PDT, there was no vaginal bleeding, and no harmful effects on the cervical organizational structure or functions compared to the surgery group, and two women delivered successfully after ALA-PDT treatment. CONCLUSIONS: The efficacy of ALA-PDT was similar to that of surgery in treating recurrent cervical HSIL following surgery, with fewer side effects.

19.
mSphere ; 9(1): e0056423, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38170984

RESUMEN

The emergence of antibiotic-resistant and biofilm-producing Staphylococcus aureus isolates presents major challenges for treating staphylococcal infections. Biofilm inhibition is an important anti-virulence strategy. In this study, a novel maleimide-diselenide hybrid compound (YH7) was synthesized and demonstrated remarkable antimicrobial activity against methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) in both planktonic cultures and biofilms. The minimum inhibitory concentration (MIC) of YH7 for S. aureus isolates was 16 µg/mL. Quantification of biofilms demonstrated that the sub-MIC (4 µg/mL) of YH7 significantly inhibits biofilm formation in both MSSA and MRSA. Confocal laser scanning microscopy analysis further confirmed the biofilm inhibitory potential of YH7. YH7 also significantly suppressed bacterial adherence to A549 cells. Moreover, YH7 treatment significantly inhibited S. aureus colonization in nasal tissue of mice. Preliminary mechanistic studies revealed that YH7 exerted potent biofilm-suppressing effects by inhibiting polysaccharide intercellular adhesin (PIA) synthesis, rather than suppressing bacterial autolysis. Real-time quantitative PCR data indicated that YH7 downregulated biofilm formation-related genes (clfA, fnbA, icaA, and icaD) and the global regulatory gene sarX, which promotes PIA synthesis. The sarX-dependent antibiofilm potential of YH7 was validated by constructing S. aureus NCTC8325 sarX knockout and complementation strains. Importantly, YH7 demonstrated a low potential to induce drug resistance in S. aureus and exhibited non-toxic to rabbit erythrocytes, A549, and BEAS-2B cells at antibacterial concentrations. In vivo toxicity assays conducted on Galleria mellonella further confirmed that YH7 is biocompatible. Overall, YH7 demonstrated potent antibiofilm activity supports its potential as an antimicrobial agent against S. aureus biofilm-related infections. IMPORTANCE Biofilm-associated infections, characterized by antibiotic resistance and persistence, present a formidable challenge in healthcare. Traditional antibacterial agents prove inadequate against biofilms. In this study, the novel compound YH7 demonstrates potent antibiofilm properties by impeding the adhesion and the polysaccharide intercellular adhesin production of Staphylococcus aureus. Notably, its exceptional efficacy against both methicillin-resistant and methicillin-susceptible strains highlights its broad applicability. This study highlights the potential of YH7 as a novel therapeutic agent to address the pressing issue of biofilm-driven infections.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Animales , Ratones , Conejos , Staphylococcus aureus , Staphylococcus aureus Resistente a Meticilina/genética , Meticilina/farmacología , Antibacterianos/farmacología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Biopelículas
20.
mSphere ; 9(1): e0061223, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38193656

RESUMEN

The emergence of Klebsiella pneumoniae carbapenemase-2 (KPC-2) and New Delhi metallo-ß-lactamase (NDM)-coproducing hypervirulent carbapenem-resistant Klebsiella pneumoniae (KPC-2-NDM-hv-CRKP) poses a certain threat to public health. Currently, only a few sporadic reports of such double-positive hv-CRKPs were available. In this study, we isolated two KPC-2-NDM-5-hv-CRKPs from elderly patients with serious underlying diseases and poor prognoses. We found both FK3122 and FK3127 were typical multidrug-resistant (MDR) isolates, exhibiting high-level resistance to both carbapenems and novel ß-lactamase inhibitors ceftazidime/avibactam. Notably, FK3122 is even resistant to cefiderocol due to multiple blaNDM-5 elements. Besides the MDR phenotype, A549 human lung epithelial cells and Galleria mellonella infection model all indicated that FK3122 and FK3127 were highly pathogenic. According to the whole-genome sequencing analysis, we observed over 10 resistant elements, and the uncommon co-existence of blaKPC-2, blaNDM-5, and virulence plasmids in both two isolates. Both virulence plasmids identified in FK3122 and FK3127 shared a high identity with classical virulence plasmid pK2044, harboring specific hypervirulent factors: rmpA and iuc operon. We also found that the resistance and virulence plasmids in FK3127 could not only be transferred to Escherichia coli EC600 independently but also together as a co-transfer, which was additionally confirmed by the S1-pulsed-field gel electrophoresis plasmid profile. Moreover, polymorphic mobile genetic elements were found surrounding resistance genes, which may stimulate the mobilization of resistance genes and result in the duplication of these elements. Considering the combination of high pathogenicity, limited therapy options, and easy transmission of KPC-2-NDM-5-hv-CRKP, our study emphasizes the need for underscores the imperative for ongoing surveillance of these pathogens.IMPORTANCEHypervirulent Klebsiella pneumoniae drug resistance has increased gradually with the emergence of carbapenem-resistant hypervirulent K. pneumoniae (hv-CRKP). However, little information is available on the virulence characteristics of the New Delhi metallo-ß-lactamase (NDM) and Klebsiella pneumoniae carbapenemase-2 (KPC-2) co-producing K. pneumoniae strains. In this study, we obtained two KPC-2-NDM-hv-CRKPs from elderly patients, each with distinct capsule types and sequence types: ST11-KL64 and ST15-KL24; these ST-type lineages are recognized as classical multidrug-resistant (MDR) K. pneumoniae. We found these KPC-2-NDM-hv-CRKPs were not only typical MDR isolates, including resistance to ceftazidime/avibactam and cefiderocol, but also displayed exceptionally high levels of pathogenicity. In addition, these high-risk factors can also be transferred to other isolates. Consequently, our study underscores the need for ongoing surveillance of these isolates due to their heightened pathogenicity, limited therapeutic options, and potential for easy transmission.


Asunto(s)
Compuestos de Azabiciclo , Enterobacteriaceae Resistentes a los Carbapenémicos , Infecciones por Klebsiella , Humanos , Anciano , Ceftazidima/farmacología , Klebsiella pneumoniae , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Infecciones por Klebsiella/epidemiología , Carbapenémicos/farmacología , Escherichia coli/genética
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