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1.
Biomaterials ; 313: 122814, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39243672

RESUMEN

Radiotherapy as a mainstay of in-depth cervical cancer (CC) treatment suffers from its radioresistance. Radiodynamic therapy (RDT) effectively reverses radio-resistance by generating reactive oxygen species (ROS) with deep tissue penetration. However, the photosensitizers stimulated by X-ray have high toxicity and energy attenuation. Therefore, X-ray responsive diselenide-bridged mesoporous silica nanoparticles (DMSNs) are designed, loading X-ray-activated photosensitizer acridine orange (AO) for spot blasting RDT like Trojan-horse against radio-resistance cervical cancer (R-CC). DMSNs can encapsulate a large amount of AO, in the tumor microenvironment (TME), which has a high concentration of hydrogen peroxide, X-ray radiation triggers the cleavage of diselenide bonds, leading to the degradation of DMSNs and the consequent release of AO directly at the tumor site. On the one hand, it solves the problems of rapid drug clearance, adverse distribution, and side effects caused by simple AO treatment. On the other hand, it fully utilizes the advantages of highly penetrating X-ray responsive RDT to enhance radiotherapy sensitivity. This approach results in ROS-induced mitochondria damage, inhibition of DNA damage repair, cell cycle arrest and promotion of cancer cell apoptosis in R-CC. The X-ray responsive DMSNs@AO hold considerable potential in overcoming obstacles for advanced RDT in the treatment of R-CC.


Asunto(s)
Nanopartículas , Dióxido de Silicio , Humanos , Animales , Rayos X , Nanopartículas/química , Femenino , Dióxido de Silicio/química , Ratones , Neoplasias del Cuello Uterino/terapia , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/patología , Especies Reactivas de Oxígeno/metabolismo , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Tolerancia a Radiación/efectos de los fármacos , Microambiente Tumoral/efectos de los fármacos , Ratones Desnudos , Células HeLa , Ratones Endogámicos BALB C , Apoptosis/efectos de los fármacos , Línea Celular Tumoral
2.
Food Chem ; 462: 141063, 2025 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-39226640

RESUMEN

In this research, the TT-COF(Fe)@NH2-CNTs was innovatively prepared through a post-modification synthetic process functionalized TT-COF@NH2-CNTs with active site (Fe), where TT-COF@NH2-CNTs was prepared via a one-pot strategy using 5,10,15,20-tetrakis (para-aminophenyl) porphyrin (TTAP), 2,3,6,7-tetra (4-formylphenyl) tetrathiafulvalene (TTF) and aminated carbon nanotubes (NH2-CNTs) as raw materials. The complex TT-COF(Fe)@NH2-CNTs material possessed porous structures, outstanding conductivity and rich catalytic sites. Thus, it can be adopted to construct electrochemical sensor with glassy carbon electrode (GCE). The TT-COF(Fe)@NH2-CNTs/GCE can selectively detect luteolin (Lu) with a wide linear plot ranging from 0.005 to 3 µM and a low limit of detection (LOD) of 1.45 nM (S/N = 3). The Lu residues in carrot samples were determined using TT-COF(Fe)@NH2-CNTs sensor and UV-visible (UV-Vis) approach. This TT-COF(Fe)@NH2-CNTs/GCE sensor paves the way for the quantification of Lu through a cost-efficient and sensitive electrochemical approach, which can make a significant step in the sensing field based on crystalline COFs.


Asunto(s)
Técnicas Electroquímicas , Luteolina , Nanotubos de Carbono , Nanotubos de Carbono/química , Luteolina/química , Luteolina/análisis , Técnicas Electroquímicas/instrumentación , Límite de Detección , Estructuras Metalorgánicas/química , Contaminación de Alimentos/análisis , Dominio Catalítico
3.
J Environ Sci (China) ; 149: 456-464, 2025 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-39181657

RESUMEN

Nitrogen-containing organic compounds (NOCs) may potentially contribute to aqueous secondary organic aerosols, yet the different formation of NOCs in aerosol particles and cloud droplets remains unclear. With the in-situ measurements performed at a mountain site (1690 m a.s.l.) in southern China, we investigated the formation of NOCs in the cloud droplets and the cloud-free particles, based on their mixing state information of NOCs-containing particles by single particle mass spectrometry. The relative abundance of NOCs in the cloud-free particles was significantly higher than those in cloud residual (cloud RES) particles. NOCs were highly correlated with carbonyl compounds (including glyoxalate and methylglyoxal) in the cloud-free particles, however, limited correlation was observed for cloud RES particles. Analysis of their mixing state and temporal variations highlights that NOCs was mainly formed from the carbonyl compounds and ammonium in the cloud-free particles, rather than in the cloud RES particles. The results support that the formation of NOCs from carbonyl compounds is facilitated in concentrated solutions in wet aerosols, rather than cloud droplets. In addition, we have identified the transport of biomass burning particles that facilitate the formation of NOCs, and that the observed NOCs is most likely contributed to the light absorption. These findings have implications for the evaluation of NOCs formation and their contribution to light absorption.


Asunto(s)
Aerosoles , Contaminantes Atmosféricos , Monitoreo del Ambiente , Nitrógeno , Compuestos Orgánicos , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/química , Nitrógeno/química , Nitrógeno/análisis , Compuestos Orgánicos/química , China , Atmósfera/química , Material Particulado/análisis , Material Particulado/química
4.
Neural Regen Res ; 20(6): 1764-1775, 2025 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-39104114

RESUMEN

JOURNAL/nrgr/04.03/01300535-202506000-00027/figure1/v/2024-08-05T133530Z/r/image-tiff Degenerative cervical myelopathy is a common cause of spinal cord injury, with longer symptom duration and higher myelopathy severity indicating a worse prognosis. While numerous studies have investigated serological biomarkers for acute spinal cord injury, few studies have explored such biomarkers for diagnosing degenerative cervical myelopathy. This study involved 30 patients with degenerative cervical myelopathy (51.3 ± 7.3 years old, 12 women and 18 men), seven healthy controls (25.7 ± 1.7 years old, one woman and six men), and nine patients with cervical spondylotic radiculopathy (51.9 ± 8.6 years old, three women and six men). Analysis of blood samples from the three groups showed clear differences in transcriptomic characteristics. Enrichment analysis identified 128 differentially expressed genes that were enriched in patients with neurological disabilities. Using least absolute shrinkage and selection operator analysis, we constructed a five-gene model (TBCD, TPM2, PNKD, EIF4G2, and AP5Z1) to diagnose degenerative cervical myelopathy with an accuracy of 93.5%. One-gene models (TCAP and SDHA) identified mild and severe degenerative cervical myelopathy with accuracies of 83.3% and 76.7%, respectively. Signatures of two immune cell types (memory B cells and memory-activated CD4+ T cells) predicted levels of lesions in degenerative cervical myelopathy with 80% accuracy. Our results suggest that peripheral blood RNA biomarkers could be used to predict lesion severity in degenerative cervical myelopathy.

5.
J Environ Sci (China) ; 148: 502-514, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095184

RESUMEN

Objective weather classification methods have been extensively applied to identify dominant ozone-favorable synoptic weather patterns (SWPs), however, the consistency of different classification methods is rarely examined. In this study, we apply two widely-used objective methods, the self-organizing map (SOM) and K-means clustering analysis, to derive ozone-favorable SWPs at four Chinese megacities in 2015-2022. We find that the two algorithms are largely consistent in recognizing dominant ozone-favorable SWPs for four Chinese megacities. In the case of classifying six SWPs, the derived circulation fields are highly similar with a spatial correlation of 0.99 between the two methods, and the difference in the mean frequency of each SWP is less than 7%. The six dominant ozone-favorable SWPs in Guangzhou are all characterized by anomaly higher radiation and temperature, lower cloud cover, relative humidity, and wind speed, and stronger subsidence compared to climatology mean. We find that during 2015-2022, the occurrence of ozone-favorable SWPs days increases significantly at a rate of 3.2 day/year, faster than the increases in the ozone exceedance days (3.0 day/year). The interannual variability between the occurrence of ozone-favorable SWPs and ozone exceedance days are generally consistent with a temporal correlation coefficient of 0.6. In particular, the significant increase in ozone-favorable SWPs in 2022, especially the Subtropical High type which typically occurs in September, is consistent with a long-lasting ozone pollution episode in Guangzhou during September 2022. Our results thus reveal that enhanced frequency of ozone-favorable SWPs plays an important role in the observed 2015-2022 ozone increase in Guangzhou.


Asunto(s)
Contaminantes Atmosféricos , Monitoreo del Ambiente , Ozono , Tiempo (Meteorología) , Ozono/análisis , China , Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos
6.
Front Microbiol ; 15: 1435360, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39234540

RESUMEN

The Heilongjiang River is one of the largest rivers in the cool temperate zone and has an abundant fish source. To date, the microbiota community in water samples and fish guts from the Heilongjiang River is still unclear. In the present study, water samples and fish guts were collected from four locations of the Heilongjiang River during both the dry season and the wet season to analyze the spatio-temporal dynamics of microbiota communities in the water environment and fish guts through 16s ribosome RNA sequencing. The water qualities showed seasonal changes in which the pH value, dissolved oxygen, and total dissolved solids were generally higher during the dry season, and the water temperature was higher during the wet season. RDA indicated that higher pH values, dissolved oxygen, and total dissolved solids promoted the formation of microbiota communities in the water samples of the dry season, while higher water temperature positively regulated the formation of microbiota communities in the water samples of the wet season. LEFSe identified five biomarkers with the most abundant difference at the genus level, of which TM7a was upregulated in the water samples of the dry season, and SM1A02, Rheinheimera, Gemmatimonas, and Vogesella were upregulated in the water samples of the wet season. Pearson analysis revealed that higher pH values and dissolved oxygen positively regulated the formation of TM7a and negatively regulated the formation of SM1A02, Rheinheimera, Gemmatimonas, and Vogesella (p < 0.05), while higher water temperature had the opposite regulatory roles in the formation of these biomarkers. The relative abundance of microbiota diversity in fish guts varies greatly between different fish species, even if the fishes were collected from the same water source, indicating that dietary habits and fish species may be key factors, affecting the formation and construction of microbiome community in fish gut. P. glenii, P. lagowskii, G. cynocephalus, and L. waleckii were the main fish resources, which were collected and identified from at least six sample points. RDA indicated that the microbiota in the water environment regulated the formation of microbiota community in the guts of G. cynocephalus and L. waleckii and had limited regulated effects on P. glenii and P. lagowskii. The present study identified the regulatory effects of water qualities on the formation of microbiota communities in the water samples and fish guts, providing valuable evidence for the protection of fish resources in the Heilongjiang River.

7.
Int Immunopharmacol ; 142(Pt A): 113054, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39241521

RESUMEN

BACKGROUND: Ulcerative colitis (UC) is becoming a global burden. Previous observational studies have unveiled associations between serum metabolites and UC, but their causal relationship remains unclear. METHODS: Serum samples from patients and mice with UC were utilized for untargeted metabolomics to identify UC-associated metabolites. Then, a two-sample mendelian randomization (MR) analysis was employed to estimate their causal relationship. Finally, mice with chronic colitis induced by dextran sodium sulfate (DSS) and macrophages were used to evaluate the protective role of creatine and underlying mechanism. RESULTS: 16 serum metabolites showed associations with UC after adjusting for confounders and multiple testing. Among them, creatine exhibited a robust protective effect against UC (OR=0.39; 95 % CI=0.27-0.56). Significant reduction of creatine was also observed in mice with acute UC induced by DSS. The inverse variance weighted (IVW) MR analysis further confirmed a causal effect of creatine on UC risk (OR IVW=0.45; 95 % CI: 0.27-0.76). Furthermore, creatine supplementation could significantly suppress weight loss, disease activity index, mucosal damage and the infiltration of macrophages in mice with chronic colitis. Remarkably, creatine promoted the polarization of bone marrow-derived macrophage (BMDM) towards M2 phenotype and upregulated the expression of il-10, il-12 and arg-1. CONCLUSIONS: This study revealed a causal relationship between creatine and UC. Creatine supplementation ameliorated chronic colitis by inhibiting the colonic infiltration of macrophages and promoting its polarization towards M2 phenotype. These results offer new insight into the pathogenesis of UC, emphasizing a potential protective role of creatine for UC.

8.
Gut Microbes ; 16(1): 2404138, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39305468

RESUMEN

Acetaminophen (APAP) overdose is a leading cause of drug-induced liver injury (DILI), with gender-specific differences in susceptibility. However, the mechanism underlying this phenomenon remains unclear. Our study reveals that the gender-specific differences in susceptibility to APAP-induced hepatotoxicity are due to differences in the gut microbiota. Through microbial multi-omics and cultivation, we observed increased gut microbiota-derived deguelin content in both women and female mice. Administration of deguelin was capable of alleviating hepatotoxicity in APAP-treated male mice, and this protective effect was associated with the inhibition of hepatocyte oxidative stress. Mechanistically, deguelin reduced the expression of thyrotropin receptor (TSHR) in hepatocytes with APAP treatment through direct interaction. Pharmacologic suppression of TSHR expression using ML224 significantly increased hepatic glutathione (GSH) in APAP-treated male mice. These findings suggest that gut microbiota-derived deguelin plays a crucial role in reducing APAP-induced hepatotoxicity in female mice, offering new insights into therapeutic strategies for DILI.


Asunto(s)
Acetaminofén , Enfermedad Hepática Inducida por Sustancias y Drogas , Microbioma Gastrointestinal , Rotenona , Animales , Acetaminofén/toxicidad , Femenino , Microbioma Gastrointestinal/efectos de los fármacos , Ratones , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Masculino , Rotenona/toxicidad , Rotenona/análogos & derivados , Estrés Oxidativo/efectos de los fármacos , Ratones Endogámicos C57BL , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Glutatión/metabolismo
9.
Insights Imaging ; 15(1): 224, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39298070

RESUMEN

OBJECTIVES: To investigate the feasibility of a deep learning-constrained compressed sensing (DL-CS) method in non-contrast-enhanced modified DIXON (mDIXON) coronary magnetic resonance angiography (MRA) and compare its diagnostic accuracy using coronary CT angiography (CCTA) as a reference standard. METHODS: Ninety-nine participants were prospectively recruited for this study. Thirty healthy subjects (age range: 20-65 years; 50% female) underwent three non-contrast mDIXON-based coronary MRA sequences including DL-CS, CS, and conventional sequences. The three groups were compared based on the scan time, subjective image quality score, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). The remaining 69 patients suspected of coronary artery disease (CAD) (age range: 39-83 years; 51% female) underwent the DL-CS coronary MRA and its diagnostic performance was compared with that of CCTA. RESULTS: The scan time for the DL-CS and CS sequences was notably shorter than that of the conventional sequence (9.6 ± 3.1 min vs 10.0 ± 3.4 min vs 13.0 ± 4.9 min; p < 0.001). The DL-CS sequence obtained the highest image quality score, mean SNR, and CNR compared to CS and conventional methods (all p < 0.001). Compared to CCTA, the accuracy, sensitivity, and specificity of DL-CS mDIXON coronary MRA per patient were 84.1%, 92.0%, and 79.5%; those per vessel were 90.3%, 82.6%, and 92.5%; and those per segment were 98.0%, 85.1%, and 98.0%, respectively. CONCLUSION: The DL-CS mDIXON coronary MRA provided superior image quality and short scan time for visualizing coronary arteries in healthy individuals and demonstrated high diagnostic value compared to CCTA in CAD patients. CRITICAL RELEVANCE STATEMENT: DL-CS resulted in improved image quality with an acceptable scan time, and demonstrated excellent diagnostic performance compared to CCTA, which could be an alternative to enhance the workflow of coronary MRA. KEY POINTS: Current coronary MRA techniques are limited by scan time and the need for noise reduction. DL-CS reduced the scan time in coronary MR angiography. Deep learning achieved the highest image quality among the three methods. Deep learning-based coronary MR angiography demonstrated high performance compared to CT angiography.

10.
Environ Pollut ; 362: 124945, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39265771

RESUMEN

Cadmium (Cd) exhibits widely olfactory toxicity to animals. We previously reported that Cd exposure induces the transcriptional dysregulation of olfactory marker proteins (OMPs) of the red imported fire ant Solenopsis invicta. However, it is still unclear how environmental Cd exposure-induced deregulation of OMPs affects the olfactory signal transduction and olfaction-driven social behavior of S. invicta. Here, we showed that S. invicta displayed dull sensory perception on bait in Cd-contaminated areas and dietary Cd ingestion by S. invicta reduced the bait search efficiency. We hypothesize that deregulation of OMPs by Cd exposure blocks the olfactory signal transduction in fire ants. Our results indicated the odor binding protein 14 (SiOBP14) was consistently inhibited in antennal sensilla of fire ants across Cd exposure at 0.5, 5 and 50 mg/kg. Function analysis in vitro and in vivo demonstrated that SiOBP14 is essential in perception of S. invicta to bait odorants. Cd-exposed fire ants showed weak odorant receptor neurons (ORNs) chemosensory signaling and electroantennogram (EAG) response. Moreover, Cd exposure repeals the preference of S. invicta to the active bait odorants, including 2-methyltetrahydrofuran-3-one, 2-methyl-3-furanthiol and 4,5-dimethylthiazole, and even triggers a behavioral transition from preference to repellence. These results indicate that Cd exposure inhibits the specific OMP expression and disrupts olfactory signal transduction, thereby inducing dull sensory perception of S. invicta to bait odorants. The findings provide new implications for monitoring and control of agricultural insect pests in heavy metal polluted areas.

11.
Transl Psychiatry ; 14(1): 384, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39304648

RESUMEN

Harm avoidance (HA) is a Cloninger personality trait that describes behavioural inhibition to avoid aversive stimuli. It serves as a predisposing factor that contributes to the development of mental disorders such as anxiety and major depressive disorder. Neuroimaging research has identified some brain anatomical and functional correlates of HA, but reported findings are inconsistent. We therefore conducted a multimodal meta-analysis of whole-brain structural and resting-state functional neuroimaging studies to identify the most stable neural substrate of HA. Included were a total of 10 structural voxel-based morphometry studies (11 datasets) and 13 functional positron emission tomography or single photon emission computed tomography studies (16 datasets) involving 3053 healthy participants without any psychiatric or neurological disorders evaluated for HA using the Three-Dimensional Personality Questionnaire (TPQ) or the Temperament and Character Inventory (TCI). The meta-analysis revealed brain volumetric correlates of HA in parietal and temporal cortices, and resting-state functional correlates in prefrontal, temporal and parietal gray matter. Volumetric and functional correlates co-occurred in the left superior frontal gyrus and left middle frontal gyrus, and were dissociated in the left rectus gyrus. Our meta-analysis is the first study to give a comprehensive picture of the structural and functional correlates of HA, a contribution that may help bridge the grievous gap between the neurobiology of HA and the pathogenesis, prevention and treatment of HA-related mental disorders.


Asunto(s)
Encéfalo , Neuroimagen Funcional , Reducción del Daño , Humanos , Encéfalo/diagnóstico por imagen , Tomografía de Emisión de Positrones , Imagen por Resonancia Magnética , Tomografía Computarizada de Emisión de Fotón Único , Personalidad/fisiología , Neuroimagen , Mapeo Encefálico
12.
Biomed Pharmacother ; 179: 117420, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39255736

RESUMEN

Radiotherapy, a precise modality for treating malignant tumors, has undergone rapid advancements in primary and clinical research. The mechanisms underlying tumor radioresistance have become significant research. With the introduction and in-depth study of cancer stem cells (CSCs) theory, CSCs have been identified as the primary factor contributing to the development of tumor radioresistance. The "stemness" of CSCs is a biological characteristic of a small subset of cells within tumor tissues, characterized by self-renewal solid ability. This characteristic leads to resistance to radiotherapy, chemotherapy, and targeted therapies, driving tumor recurrence and metastasis. Another study revealed that cellular autophagy plays a pivotal role in maintaining the "stemness" of CSCs. Autophagy is a cellular mechanism that degrades proteins and organelles to generate nutrients and energy in response to stress. This process maintains cellular homeostasis and contributes to CSCs radioresistance. Furthermore, ionizing radiation (IR) facilitates epithelial-to-mesenchymal transition (EMT), vascular regeneration, and other tumor processes by influencing the infiltration of M2-type tumor-associated macrophages (TAMs). IR promotes the activation of the classical immunosuppressive "switch," PD-1/PD-L1, which diminishes T-cell secretion, leading to immune evasion and promoting radioresistance. Interestingly, recent studies have found that the immune pathway PD-1/PD-L1 is closely related to cellular autophagy. However, the interrelationships between immunity, autophagy, and radioresistance of CSCs and the regulatory mechanisms involved remain unclear. Consequently, this paper reviews recent research to summarize these potential connections, aiming to establish a theoretical foundation for future studies and propose a new model for the network regulation of immunity, autophagy, and radioresistance of tumor cells.


Asunto(s)
Autofagia , Neoplasias , Células Madre Neoplásicas , Tolerancia a Radiación , Células Madre Neoplásicas/efectos de la radiación , Células Madre Neoplásicas/patología , Células Madre Neoplásicas/inmunología , Humanos , Animales , Neoplasias/radioterapia , Neoplasias/patología , Neoplasias/inmunología , Microambiente Tumoral/inmunología , Transición Epitelial-Mesenquimal
13.
DNA Repair (Amst) ; 142: 103754, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39232366

RESUMEN

Transcription reprogramming is essential to carry out a variety of cell dynamics such as differentiation and stress response. During reprogramming of transcription, a number of adverse effects occur and potentially compromise genomic stability. Formaldehyde as an obligatory byproduct is generated in the nucleus via oxidative protein demethylation at regulatory regions, leading to the formation of DNA crosslinking damage. Elevated levels of transcription activities can result in the accumulation of unscheduled R-loop. DNA strand breaks can form if processed 5-methylcytosines are exercised by DNA glycosylase during imprint reversal. When cellular differentiation involves a large number of genes undergoing transcription reprogramming, these endogenous DNA lesions and damage-prone structures may pose a significant threat to genome stability. In this review, we discuss how DNA damage is formed during cellular differentiation, cellular mechanisms for their removal, and diseases associated with transcription reprogramming.


Asunto(s)
Reprogramación Celular , Daño del ADN , Transcripción Genética , Humanos , Animales , Reparación del ADN , Diferenciación Celular , Inestabilidad Genómica
14.
Int J Biol Macromol ; 279(Pt 3): 135317, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39245117

RESUMEN

Microbial seed coatings serve as effective, labor-saving, and ecofriendly means of controlling soil-borne plant diseases. However, the survival of microbial agents on seed surfaces and in the rhizosphere remains a crucial challenge. In this work, we embedded a biocontrol bacteria (Bacillus subtilis ZF71) in sodium alginate (SA)/pectin (PC) hydrogel as a seed coating agent to control Fusarium root rot in cucumber. The formula of SA/PC hydrogel was optimized with the highest coating uniformity of 90 % in cucumber seeds. SA/PC hydrogel was characterized using rheological, gel content, and water content tests, thermal gravimetric analysis, and Fourier transform infrared spectroscopy. Bacillus subtilis ZF71 within the SA/PC hydrogel network formed a biofilm-like structure with a high viable cell content (8.30 log CFU/seed). After 37 days of storage, there was still a high number of Bacillus subtilis ZF71 cells (7.23 log CFU/seed) surviving on the surface of cucumber seeds. Pot experiments revealed a higher control efficiency against Fusarium root rot in ZF71-SA/PC cucumber seeds (53.26 %) compared with roots irrigated with a ZF71 suspension. Overall, this study introduced a promising microbial seed coating strategy based on biofilm formation that improved performance against soil-borne plant diseases.

15.
Bioresour Technol ; 413: 131456, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39260728

RESUMEN

Limited scientific evidence exists on phosphorus immobilization under autogenetic electrochemical reactions in composting systems. This study exploited a composting procedure using microbial fuel cell (MFC) to ascertain phosphorus redistribution during composting process. Compared to the control without MFC equipment, MFC-assisted treatment yielded a 13 % decrease in phosphorus availability due to the transformation of exchangeable fraction (Ex-P) to aluminum-bound (Al-P) and calcium-bound (Ca-P) fractions. During the composting process, organic humification primarily controlled phosphorus redistribution and immobilization. Biotic factors, including bacterial communities (i.e., Firmicutes, Proteobacteria, Bacteroidota, and Gemmatimonadota) and functional enzymes (i.e., acid phosphatase, alkaline phosphatase, phytase, and C-P lyase), significantly influenced phosphorus availability in the composting systems. Temperature-dependent composting phases restricted microbial actions on phosphorus transformation. These findings highlight the mechanisms underlying phosphorus transformation in composting systems, and provide valuable insights for advancing composting technology and protecting agricultural ecosystems.

16.
Virol Sin ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39265703

RESUMEN

Respiratory syncytial virus (RSV) is a significant cause of acute lower respiratory tract infection (ALRTI) in children under five years of age. Between 2017 and 2021, 396 complete sequences of the RSV F gene were obtained from 500 RSV-positive throat swabs collected from ten hospitals across nine provinces in China. In addition, 151 sequences from China were sourced from GenBank and GISAID, making a total of 549 RSV F gene sequences subjected to analysis. Phylogenetic and genetic diversity analyses revealed that the RSV F genes circulating in China from 2017 to 2021 have remained relatively conserved, although some amino acids (AAs) have undergone changes. AA mutations with frequencies ≥ 10% were identified at six sites and the p27 region: V384I (site I), N276S (site II), R213S (site Ø), and K124N (p27) for RSV A; F45L (site I), M152I/L172Q/S173L/I185V/K191R (site V), and R202Q/I206M/Q209R (site Ø) for RSV B. Comparing mutational frequencies in RSV-F before and after 2020 revealed minor changes for RSV A, while the K191R, I206M, and Q209R frequencies increased by over 10% in RSV B. Notably, the nirsevimab-resistant mutation, S211N in RSV B, increased in frequency from 0% to 1.15%. Both representative strains aligned with the predicted RSV-F structures of their respective prototypes exhibited similar conformations, with low root-mean-square deviation values. These results could provide foundational data from China for the development of RSV mAbs and vaccines.

17.
Med Image Anal ; 99: 103347, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39316997

RESUMEN

Automatic segmentation of polyps from colonoscopy images plays a critical role in the early diagnosis and treatment of colorectal cancer. Nevertheless, some bottlenecks still exist. In our previous work, we mainly focused on polyps with intra-class inconsistency and low contrast, using ICGNet to solve them. Due to the different equipment, specific locations and properties of polyps, the color distribution of the collected images is inconsistent. ICGNet was designed primarily with reverse-contour guide information and local-global context information, ignoring this inconsistent color distribution, which leads to overfitting problems and makes it difficult to focus only on beneficial image content. In addition, a trustworthy segmentation model should not only produce high-precision results but also provide a measure of uncertainty to accompany its predictions so that physicians can make informed decisions. However, ICGNet only gives the segmentation result and lacks the uncertainty measure. To cope with these novel bottlenecks, we further extend the original ICGNet to a comprehensive and effective network (UM-Net) with two main contributions that have been proved by experiments to have substantial practical value. Firstly, we employ a color transfer operation to weaken the relationship between color and polyps, making the model more concerned with the shape of the polyps. Secondly, we provide the uncertainty to represent the reliability of the segmentation results and use variance to rectify uncertainty. Our improved method is evaluated on five polyp datasets, which shows competitive results compared to other advanced methods in both learning ability and generalization capability. The source code is available at https://github.com/dxqllp/UM-Net.

18.
Materials (Basel) ; 17(17)2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39274760

RESUMEN

As the demand for high-performance dissimilar material joining continues to increase in fields such as aerospace, biomedical engineering, and electronics, the welding technology of dissimilar materials has become a focus of research. However, due to the differences in material properties, particularly in the welding between metals and non-metals, numerous challenges arise. The formation and quality of the weld seam are strongly influenced by laser process parameters. In this study, successful welding of high-borosilicate glass to a TC4 titanium alloy, which was treated with high-temperature oxidation, was achieved using a millisecond pulsed laser. A series of process parameter comparison experiments were designed, and the laser welding behavior of the titanium alloy and glass under different process parameters was investigated using scanning electron microscopy (SEM) and a universal testing machine as the primary analysis and testing equipment. The results revealed that changes in process parameters significantly affect the energy input and accumulation during the welding process. The maximum joint strength of 60.67 N was obtained at a laser power of 180 W, a welding speed of 3 mm/s, a defocus distance of 0 mm, and a frequency of 10 Hz. Under the action of the laser, the two materials mixed and penetrated into the molten pool, thus achieving a connection. A phase, Ti5Si3, was detected at the fracture site, indicating that both mechanical bonding and chemical bonding reactions occurred between the high-borosilicate glass and the TC4 titanium alloy during the laser welding process.

19.
Plant Dis ; 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39320379

RESUMEN

Broccoli (Brassica oleracea L. var. italica) is one of the important cruciferous vegetables in China, known for its considerable economic and nutritional value (Li et al. 2021). In September 2023, leaf spot disease was observed on broccoli seedlings in the commercial fields in Weifang City, Shandong Province, China (119°15'E, 36°70'N). Further investigation revealed that the disease incidence was approximately 60% in 4.5 square hectometers (hm2) broccoli field, resulting in substantial economic losses. This disease primarily affects the leaves, manifesting distinct symptoms such as circular, dark necrotic spots that gradually lighten and are encircled by a chlorotic halo. Some lesions further develop a black or purplish border, exhibit concentric zonation, and eventually fall off, leaving behind holes, as shown in Figure S1B and C. In severe cases, decay originates from the central perforation and spreads outwards, as shown in Figure S1A. To identify the causal agent of this disease, infected leaf tissues were collected and surface disinfected by immersing in 75% ethanol for 30 seconds, followed by three rinses with sterile water. The samples were grinded in sterile deionized water, and the extract was plated on NA. After incubation at 28°C for 48 h, individual colonies were transferred to fresh NA plates. A total of 12 strains with the similar morphological characteristics were isolated from diseased samples collected from the three plots. After 48 hours of growth on NA medium at 28℃, each colony attained a diameter ranging from 3 to 5 mm. These colonies appeared yellow, slightly elevated, nearly circular in shape, with a smooth and moist edge. Three representative strains were selected for further investigation. All strains were Gram-negative, aerobic, and rod-shaped. The analysis of BIOLOG GENIII microplate system revealed the capability of three isolates using cellobiose, trehalose, glucose, mannose, galactose, and sucrose. Furthermore, the isolates were unable to hydrolyze arginine and utilize rhamnose and inositol. The 16S rRNA gene was amplified and sequenced to confirm that three isolated bacteria belong to the genus Xanthomonas (OR772321-OR772323), followed by PCR amplification for 4 housekeeping genes atpD, dnaK, gyrB, and rpoD (Young et al. 2008; Saux et al. 2015). The obtained sequences were submitted to the GenBank under accessions OR789628-OR789630, OR785471-OR785473, OR789631-OR789633, and OR785468-OR785470. Gene sequences were aligned, concatenated, and used to generate a phylogenetic tree using the neighbor-joining method in MEGA11 (Tamura et al. 2021). The phylogenetic analysis revealed that all the three isolates were clustered with Xanthomonas campestris pv. raphani strains 5055 and 576, respectively (Figure S2). (Dubrow et al. 2022). These results were consistent with those of the reported X. campestris pv. raphanin (Cruz et al. 2015). To verify the pathogenicity of these strains, we used a spray inoculation method. In detail, bacterial suspensions (30 mL per treatment) containing approximately 108 CFU/ml were sprayed onto healthy, four-week-old broccoli plants and incubated in a phytotron at 28°C and above 90% RH. Negative controls were performed using sterile distilled water. Each isolate underwent three trials and each treatment included 12 broccoli seedlings. Leaf spot symptoms were observed on 5 days post inoculation, as shown in Figure S1E, F and G. Negative control plants showed no symptoms (Figure S1D). We further re-isolated the bacterium from the symptomatic plants and verifying the bacteria as X. campestris pv. raphanin with the aforementioned sequence analysis, thereby fulfilling Koch's postulates. To our knowledge, this is the first report of X. campestris pv. raphani causing leaf spot disease on broccoli in China. This study enhances our understanding of the pathogenic bacterium on broccoli and lays the groundwork for developing targeted management strategies.

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