Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 6.689
Filtrar
1.
Microbiome ; 12(1): 80, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38715137

RESUMEN

BACKGROUND: Antibiotic exposure can occur in medical settings and from environmental sources. Long-term effects of brief antibiotic exposure in early life are largely unknown. RESULTS: Post a short-term treatment by ceftriaxone to C57BL/6 mice in early life, a 14-month observation was performed using 16S rRNA gene-sequencing technique, metabolomics analysis, and metagenomics analysis on the effects of ceftriaxone exposure. Firstly, the results showed that antibiotic pre-treatment significantly disturbed gut microbial α and ß diversities (P < 0.05). Both Chao1 indices and Shannon indices manifested recovery trends over time, but they didn't entirely recover to the baseline of control throughout the experiment. Secondly, antibiotic pre-treatment reduced the complexity of gut molecular ecological networks (MENs). Various network parameters were affected and manifested recovery trends over time with different degrees, such as nodes (P < 0.001, R2 = 0.6563), links (P < 0.01, R2 = 0.4543), number of modules (P = 0.0672, R2 = 0.2523), relative modularity (P = 0.6714, R2 = 0.0155), number of keystones (P = 0.1003, R2 = 0.2090), robustness_random (P = 0.79, R2 = 0.0063), and vulnerability (P = 0.0528, R2 = 0.28). The network parameters didn't entirely recover. Antibiotic exposure obviously reduced the number of key species in gut MENs. Interestingly, new keystones appeared during the recovery process of network complexity. Changes in network stability might be caused by variations in network complexity, which supports the ecological theory that complexity begets stability. Besides, the metabolism profiles of the antibiotic group and control were significantly different. Correlation analysis showed that antibiotic-induced differences in gut microbial metabolism were related to MEN changes. Antibiotic exposure also caused long-term effects on gut microbial functional networks in mice. CONCLUSIONS: These results suggest that short-term antibiotic exposure in early life will cause long-term negative impacts on gut microbial diversity, MENs, and microbial metabolism. Therefore, great concern should be raised about children's brief exposure to antibiotics if the results observed in mice are applicable to humans. Video Abstract.


Asunto(s)
Antibacterianos , Bacterias , Microbioma Gastrointestinal , Ratones Endogámicos C57BL , ARN Ribosómico 16S , Microbioma Gastrointestinal/efectos de los fármacos , Animales , Antibacterianos/farmacología , Antibacterianos/efectos adversos , Ratones , ARN Ribosómico 16S/genética , Bacterias/genética , Bacterias/clasificación , Bacterias/metabolismo , Bacterias/efectos de los fármacos , Ceftriaxona/farmacología , Metagenómica/métodos , Masculino , Metabolómica , Heces/microbiología
2.
ACS Nano ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38723039

RESUMEN

Transition metal oxides are promising catalysts for catalytic oxidation reactions but are hampered by low room-temperature activities. Such low activities are normally caused by sparse reactive sites and insufficient capacity for molecular oxygen (O2) activation. Here, we present a dual-stimulation strategy to tackle these two issues. Specifically, we import highly dispersed nickel (Ni) atoms onto MnO2 to enrich its oxygen vacancies (reactive sites). Then, we use molecular ozone (O3) with a lower activation energy as an oxidant instead of molecular O2. With such dual stimulations, the constructed O3-Ni/MnO2 catalytic system shows boosted room-temperature activity for toluene oxidation with a toluene conversion of up to 98%, compared with the O3-MnO2 (Ni-free) system with only 50% conversion and the inactive O2-Ni/MnO2 (O3-free) system. This leap realizes efficient room-temperature catalytic oxidation of transition metal oxides, which is constantly pursued but has always been difficult to truly achieve.

4.
Cont Lens Anterior Eye ; : 102178, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724427

RESUMEN

OBJECTIVE: This study aimed to compare the changes in corneal morphological characteristics in corneal topography assessments performed after wearing orthokeratology (OK) lenses with different back optic zone diameters (BOZDs). These changes included the change ratios of the apical corneal power (ACP), the maximum relative corneal refractive power (mRCRP), and the treatment zone diameter (TZD). METHODS: Data from 133 children with myopia (average age 9.50 ± 1.23 years) treated at Fudan University Eye and Ear, Nose, and Throat Hospital were retrospectively analyzed. All participants wore the same brand of tangent-design OK lens (corneal refractive therapy, CRT). According to the BOZD, the patients were divided into two groups, of 5.0 and 6.0 mm BOZD, respectively. Corneal topography was analyzed at baseline, as well as 1 day, 1 week, and 1 month after wearing the lenses, and the change ratios of ACP, mRCRP, and TZD were compared between the two groups. RESULTS: The change ratio of the ACP did not differ significantly between the BOZD 5.0 and 6.0 groups after 1 day or 1 week of lens wear (P = 0.170 and P = 0.113, respectively). However, after 1 month of lens wear, the change ratio of the ACP in the BOZD 5.0 group was significantly larger than that in the BOZD 6.0 group (P < 0.001). After 1 month of lens wear, the mRCRP along the horizontal and vertical meridians was higher (P < 0.05) and the TZD was significantly smaller (P < 0.001) in the BOZD 5.0 group than in the BOZD 6.0 group. CONCLUSION: In CRT OK lenses, a small BOZD lens can produce faster corneal shaping, a larger mRCRP, and a smaller TZD, which may have a better effect on slowing ocular axial length elongation. The lens parameters are also a factor affecting the TZD.

5.
Chem Commun (Camb) ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38743417

RESUMEN

Two anionic tetrahedral cages were self-assembled as the only observable products in weakly basic water via imine condensation. The success of the high-yielding formation of the cages in water relies on (i) multivalency enhancing the stability of the imine bond and affording these cages water compatibility and (ii) a guest template with a complementary size and geometry that provides a hydrophobic driving force by occupying the corresponding cage cavity. When all four precursors, namely two trisaldehydes and two trisamines, were combined in water, narcissistic self-sorting occurred when both guest templates were present. In organic media where the hydrophobic effect is absent, narcissistic self-sorting did not occur in the analogous cage systems, confirming the importance of guest templates.

7.
bioRxiv ; 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38746102

RESUMEN

Human immune system (HIS) mice constructed in various ways are widely used for investigations of human immune responses to pathogens, transplants and immunotherapies. In HIS mice that generate T cells de novo from hematopoietic progenitors, T cell-dependent multisystem autoimmune disease occurs, most rapidly when the human T cells develop in the native NOD.Cg- Prkdc scid Il2rg tm1Wjl (NSG) mouse thymus, where negative selection is abnormal. Disease develops very late when human T cells develop in human fetal thymus grafts, where robust negative selection is observed. We demonstrate here that PD-1 + CD4 + peripheral (Tph) helper-like and follicular (Tfh) helper-like T cells developing in HIS mice can induce autoimmune disease. Tfh-like cells were more prominent in HIS mice with a mouse thymus, in which the highest levels of IgG were detected in plasma, compared to those with a human thymus. While circulating IgG and IgM antibodies were autoreactive to multiple mouse antigens, in vivo depletion of B cells and antibodies did not delay the development of autoimmune disease. Conversely, adoptive transfer of enriched Tfh- or Tph-like cells induced disease and autoimmunity-associated B cell phenotypes in recipient mice containing autologous human APCs without T cells. T cells from mice with a human thymus expanded and induced disease more rapidly than those originating in a murine thymus, implicating HLA-restricted T cell-APC interactions in this process. Since Tfh, Tph, autoantibodies and LIP have all been implicated in various forms of human autoimmune disease, the observations here provide a platform for the further dissection of human autoimmune disease mechanisms and therapies.

8.
Materials (Basel) ; 17(9)2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38730759

RESUMEN

To investigate the effect of hybrid fibers on the compressive strength of aeolian sand concrete, compressive strength tests were conducted on aeolian sand concrete with single polypropylene fibers and aeolian sand concrete with mixed polypropylene fibers and calcium carbonate whisker, and their variation rules were studied. Using scanning electron microscopy and nuclear magnetic resonance, the microstructure and pore structure of specimens were analyzed, and a mathematical model of the relationship between compressive strength and pore structure was established with gray entropy analysis. The results show that the compressive strength of hybrid fiber aeolian sand concrete first increases and then decreases with an increase in whisker content. When the replacement rate of wind-accumulated sand is 80% and the fiber content is 0.1%, the optimal volume content of whisker is 0.4%, and the 28 d compressive strength of whisker is 24.8% higher than that of aeolian sand concrete. The average relative errors of compressive strength at 7 d and 28 d are 8.16% and 7.48%, respectively, using the GM (1,3) model. This study can provide effective theoretical support for the application of calcium carbonate whisker and polypropylene fibers in aeolian sand concrete.

9.
Materials (Basel) ; 17(9)2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38730935

RESUMEN

Diamond-like carbon (DLC) coatings are effective in protecting the key components of marine equipment and can greatly improve their short-term performance (1.5~4.5 h). However, the lack of investigation into their long-term (more than 200 h) performance cannot meet the service life requirements of marine equipment. Here, three multilayered DLC coatings, namely Ti/DLC, TiCx/DLC, and Ti-TiCx/DLC, were prepared, and their long-term corrosion resistance was investigated. Results showed that the corrosion current density of all DLC coatings was reduced by 1-2 orders of magnitude compared with bare 316L stainless steel (316Lss). Moreover, under long-term (63 days) immersion in a 3.5 wt.% NaCl solution, all DLC coatings could provide excellent long-term corrosion protection for 316Lss, and Ti-TiCx/DLC depicted the best corrosion resistance; the polarization resistances remained at ~3.0 × 107 Ω·cm2 after immersion for 63 days, with more interfaces to hinder the penetration of the corrosive media. Meanwhile, during neutral salt spray (3000 h), the corrosion resistance of Ti/DLC and TiCx/DLC coatings showed a certain degree of improvement because the insoluble corrosion products at the defects blocked the subsequent corrosion. This study can provide a route to designing amorphous carbon protective coatings for long-term marine applications in different environments.

10.
Foods ; 13(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38731757

RESUMEN

The traditional fermentation process of soy sauce employs a hyperhaline model and has a long fermentation period. A hyperhaline model can improve fermentation speed, but easily leads to the contamination of miscellaneous bacteria and fermentation failure. In this study, after the conventional koji and moromi fermentation, the fermentation broth was pasteurized and diluted, and then inoculated with three selected microorganisms including Corynebacterium glutamicum, Corynebacterium ammoniagenes, and Lactiplantibacillus plantarum for secondary fermentation. During this ten-day fermentation, the pH, free amino acids, organic acids, nucleotide acids, fatty acids, and volatile compounds were analyzed. The fermentation group inoculated with C. glutamicum accumulated the high content of amino acid nitrogen of 0.92 g/100 mL and glutamic acid of 509.4 mg/100 mL. The C. ammoniagenes group and L. plantarum group were rich in nucleotide and organic acid, respectively. The fermentation group inoculated with three microorganisms exhibited the best sensory attributes, showing the potential to develop a suitable fermentation method. The brewing speed of the proposed process in this study was faster than that of the traditional method, and the umami substances could be significantly accumulated in this low-salt fermented model (7% w/v NaCl). This study provides a reference for the low-salt and rapid fermentation of seasoning.

12.
Discov Oncol ; 15(1): 149, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38720108

RESUMEN

PURPOSE: The research endeavors to explore the implications of CD47 in cancer immunotherapy effectiveness. Specifically, there is a gap in comprehending the influence of CD47 on the tumor immune microenvironment, particularly in relation to CD8 + T cells. Our study aims to elucidate the prognostic and immunological relevance of CD47 to enhance insights into its prospective utilities in immunotherapeutic interventions. METHODS: Differential gene expression analysis, prognosis assessment, immunological infiltration evaluation, pathway enrichment analysis, and correlation investigation were performed utilizing a combination of R packages, computational algorithms, diverse datasets, and patient cohorts. Validation of the concept was achieved through the utilization of single-cell sequencing technology. RESULTS: CD47 demonstrated ubiquitous expression across various cancer types and was notably associated with unfavorable prognostic outcomes in pan-cancer assessments. Immunological investigations unveiled a robust correlation between CD47 expression and T-cell infiltration rather than T-cell exclusion across multiple cancer types. Specifically, the CD47-high group exhibited a poorer prognosis for the cytotoxic CD8 + T cell Top group compared to the CD47-low group, suggesting a potential impairment of CD8 + T cell functionality by CD47. The exploration of mechanism identified enrichment of CD47-associated differentially expressed genes in the CD8 + T cell exhausted pathway in multiple cancer contexts. Further analyses focusing on the CD8 TCR Downstream Pathway and gene correlation patterns underscored the significant involvement of TNFRSF9 in mediating these effects. CONCLUSION: A robust association exists between CD47 and the exhaustion of CD8 + T cells, potentially enabling immune evasion by cancer cells and thereby contributing to adverse prognostic outcomes. Consequently, genes such as CD47 and those linked to T-cell exhaustion, notably TNFRSF9, present as promising dual antigenic targets, providing critical insights into the field of immunotherapy.

13.
Mol Cell Proteomics ; : 100783, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38729610

RESUMEN

High myopia is a leading cause of blindness worldwide, among which pathologic myopia, characterized by typical myopic macular degeneration, is the most detrimental. However, its pathogenesis remains largely unknown. Here, using an HuProt array, we first initiated a serological autoantibody profiling of high myopia and identified 18 potential autoantibodies, of which anti-LIMS1 autoantibody was validated by a customized focused microarray. Further subgroup analysis revealed its actual relevance to pathologic myopia, rather than simple high myopia without myopic macular degeneration. Mechanistically, anti-LIMS1 autoantibody predominantly belonged to IgG1/IgG2/IgG3 subclasses. Serum IgG obtained from patients with pathologic myopia could disrupt the barrier function of retinal pigment epithelial cells via cytoskeleton disorganization and tight junction component reduction, and also trigger a pro-inflammatory mediator cascade in retinal pigment epithelial cells, which were all attenuated by depletion of anti-LIMS1 autoantibody. Together, these data uncover a previously unrecognized autoimmune etiology of myopic macular degeneration in pathologic myopia.

14.
J Hum Genet ; 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730005

RESUMEN

Mitochondrial diseases are a group of genetic diseases caused by mutations in mitochondrial DNA and nuclear DNA. However, the genetic spectrum of this disease is not yet complete. In this study, we identified a novel variant m.4344T>C in mitochondrial tRNAGln from a patient with developmental delay. The mutant loads of m.4344T>C were 95% and 89% in the patient's blood and oral epithelial cells, respectively. Multialignment analysis showed high evolutionary conservation of this nucleotide. TrRosettaRNA predicted that m.4344T>C variant would introduce an additional hydrogen bond and alter the conformation of the T-loop. The transmitochondrial cybrid-based study demonstrated that m.4344T>C variant impaired the steady-state level of mitochondrial tRNAGln and decreased the contents of mitochondrial OXPHOS complexes I, III, and IV, resulting in defective mitochondrial respiration, elevated mitochondrial ROS production, reduced mitochondrial membrane potential and decreased mitochondrial ATP levels. Altogether, this is the first report in patient carrying the m.4344T>C variant. Our data uncover the pathogenesis of the m.4344T>C variant and expand the genetic mutation spectrum of mitochondrial diseases, thus contributing to the clinical diagnosis of mitochondrial tRNAGln gene variants-associated mitochondrial diseases.

15.
PLoS One ; 19(5): e0296654, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38728313

RESUMEN

In the era of the rapid development of e-commerce, many retailers choose to launch promotional activities to become consumers' first choice for shopping. Since price discounts can greatly attract consumers, the e-commerce platforms have also begun to implement discount pricing. It is urgent for e-commerce platforms and retailers to formulate reasonable discount strategies to achieve sustainable business. In this paper, we construct a dynamic game model for implementing discount pricing on an e-commerce platform and two retailers, we study the market equilibrium between the two retailers and the e-commerce platform under various scenarios that considering consumers' strategic waiting behavior and competition between the two retailers, we further discuss the effectiveness of retailer discount pricing and the double discount pricing of the platform and retailers. We show that the optimal pricing decreases as the difference in product quality narrows under both pricing strategies. Low-quality retailers implementing a double discount pricing strategy are in relatively higher demand only when the difference in product quality is small. High-quality retailers implementing the retailer discount pricing strategy are in relatively higher demand only when the product quality difference is large. Double discount pricing is desirable for both e-commerce platforms and retailers and can be used to effectively achieve Pareto improvement in the market by increasing their expected profit. Our results emphasize the role of product quality and the value of the double discount pricing strategy. The double discount pricing strategy weakens the profit advantage that retailers and platforms gain from it as the rebate intensity and rebate redemption rates increase.


Asunto(s)
Comercio , Comportamiento del Consumidor , Comercio/economía , Comportamiento del Consumidor/economía , Humanos , Costos y Análisis de Costo , Modelos Económicos
16.
Magn Reson Med ; 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730565

RESUMEN

PURPOSE: To develop a highly accelerated multi-echo spin-echo method, TEMPURA, for reducing the acquisition time and/or increasing spatial resolution for kidney T2 mapping. METHODS: TEMPURA merges several adjacent echoes into one k-space by either combining independent echoes or sharing one echo between k-spaces. The combined k-space is reconstructed based on compressed sensing theory. Reduced flip angles are used for the refocusing pulses, and the extended phase graph algorithm is used to correct the effects of indirect echoes. Two sequences were developed: a fast breath-hold sequence; and a high-resolution sequence. The performance was evaluated prospectively on a phantom, 16 healthy subjects, and two patients with different types of renal tumors. RESULTS: The fast TEMPURA method reduced the acquisition time from 3-5 min to one breath-hold (18 s). Phantom measurements showed that fast TEMPURA had a mean absolute percentage error (MAPE) of 8.2%, which was comparable to a standardized respiratory-triggered sequence (7.4%), but much lower than a sequence accelerated by purely k-t undersampling (21.8%). High-resolution TEMPURA reduced the in-plane voxel size from 3 × 3 to 1 × 1 mm2, resulting in improved visualization of the detailed anatomical structure. In vivo T2 measurements demonstrated good agreement (fast: MAPE = 1.3%-2.5%; high-resolution: MAPE = 2.8%-3.3%) and high correlation coefficients (fast: R = 0.85-0.98; high-resolution: 0.82-0.96) with the standardized method, outperforming k-t undersampling alone (MAPE = 3.3-4.5%, R = 0.57-0.59). CONCLUSION: TEMPURA provides fast and high-resolution renal T2 measurements. It has the potential to improve clinical throughput and delineate intratumoral heterogeneity and tissue habitats at unprecedented spatial resolution.

17.
Nano Lett ; 24(19): 5690-5698, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38700237

RESUMEN

Long-term tumor starvation may be a potential strategy to elevate the antitumor immune response by depriving nutrients. However, combining long-term starvation therapy with immunotherapy often yields limited efficacy due to the blockage of immune cell migration pathways. Herein, an intelligent blood flow regulator (BFR) is first established through photoactivated in situ formation of the extravascular dynamic hydrogel to compress blood vessels, which can induce long-term tumor starvation to elicit metabolic stress in tumor cells without affecting immune cell migration pathways. By leveraging methacrylate-modified nanophotosensitizers (HMMAN) and biodegradable gelatin methacrylate (GelMA), the developed extravascular hydrogel dynamically regulates blood flow via enzymatic degradation. Additionally, aPD-L1 loaded into HMMAN continuously blocks immune checkpoints. Systematic in vivo experiments demonstrate that the combination of immune checkpoint blockade (ICB) and BFR-induced metabolic stress (BIMS) significantly delays the progression of Lewis lung and breast cancers by reshaping the tumor immunogenic landscape and enhancing antitumor immune responses.


Asunto(s)
Hidrogeles , Hidrogeles/química , Animales , Ratones , Humanos , Línea Celular Tumoral , Femenino , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Inmunoterapia , Gelatina/química , Metacrilatos/química , Metacrilatos/farmacología , Neoplasias de la Mama/inmunología
18.
Heliyon ; 10(9): e30310, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38742080

RESUMEN

Background: Methods for washed microbiota transplantation (WMT) through the mid-gut include transendoscopic enteral tubing (TET) and manual spiral nasojejunal tube (SNT) placement have not been studied. Methods: This prospective interventional study was performed at a single centre. Patients were divided into the SNT and mid-gut TET groups based on their conditions and wishes. In the SNT group, an SNT was passively inserted into the stomach, and abdominal X-rays were taken within 24 h to confirm tube placement in the small intestine. In the mid-gut TET group, mid-gut TET was placed in the small intestine for gastroscopy. Data on the clinical efficacy of WMT, intubation time, cost, overall comfort score, adverse reactions, etc., were collected from the two groups. Results: Sixty-three patients were included in the study (SNT group (n = 40) and mid-gut TET group (n = 23)). The clinical efficacy of WMT in the SNT and mid-gut TET groups was 90 % and 95.7 %, respectively (P = 0.644). Compared with the mid-gut TET group, the SNT group showed a shorter operation time (120 s vs. 258 s, P = 0.001) and a lower average cost (641.7 yuan vs. 1702.1 yuan, P = 0.001). There was no significant difference in the overall comfort score or the incidence of common discomfort symptoms between the two groups. Conclusion: The different implantation methods have different advantages; compared with mid-gut TET placement, manual SNT placement provides some benefits.

20.
Audiol Neurootol ; 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38763131

RESUMEN

BACKGROUND: Otosclerosis is a bone disorder affecting the labyrinthine capsule that leads to conductive and occasionally sensorineural hearing loss. The etiology of otosclerosis remains unknown; factors such as infection, hormones, inflammation, genetics, and autoimmunity have been discussed. Treatment consists primarily of surgical stapes replacement and cochlear implantation. High-resolution computed tomography (HRCT) is routinely used to visualize bone pathology. In the present study, we used synchrotron radiation phase-contrast imaging (SR-PCI) to examine otosclerosis plaques in a temporal bone for the first time. The primary aim was to study their three-dimensional (3D) outline, vascular interrelationships and connections to the middle ear. MATERIAL AND METHODS: A donated ear from a patient with otosclerosis who had undergone partial stapedectomy with insertion of a stapes wire prosthesis was investigated using SR-PCI and compared with a control ear. Otosclerotic lesions were 3D rendered using the composite with shading technique. Scalar opacity and color mapping were adjusted to display volume properties with the removal of bones to enhance surfaces. Vascular bone channels were segmented, and the communications between lesions and the middle ear were established. RESULTS: Fenestral, cochlear, meatal and vestibular lesions were outlined three-dimensionally. Vascular bone channels were found to be frequently connected to the middle ear mucosa, perilabyrinthine air spaces, and facial nerve vessels. Round window lesions partly embedded the cochlear aqueduct which was pathologically narrowed, while the inferior cochlear vein was significantly dilated in its proximal part. DISCUSSION: Otosclerotic/otospongiotic lesions were imaged for the first time using SR-PCI and 3D rendering. The presence of shunts and abnormal vascular connections to the labyrinth appeared to result in hyper-vascularization, overloading the venous system, and leading to sensorineural hearing loss. We speculate about possible local treatments to alleviate the impact of such critical lesions on the labyrinthine micro-circulation.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA