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1.
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.

2.
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
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.
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
5.
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
6.
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.

7.
Medicine (Baltimore) ; 103(38): e39723, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39312384

RESUMEN

Polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) as 2 types of autoimmune diseases are frequently concomitant, and Mendelian randomization (MR) was applied in this study to assess the causal relationship between them. In this study, single-nucleotide polymorphism (SNP) was used as the instrumental variable for Mendelian analysis, and the SNP data of GCA and PMR were obtained from the FinnGen Biobank databases. SNPs are significantly correlated with GCA and PMR and were screened based on preset thresholds. Inverse variance weighted analysis was used as the main analysis, supplemented with MR-Egger and weighted median. The evidence of the impact of GCA on PMR risk was found in inverse variance weighted results (odds ratio, 1.22 [95% confidence interval, 1.11-1.34]; P < .01), and the evidence of the impact of PMR on GCA risk has also been found (odds ratio, 1.58 [95% confidence interval, 1.28-1.96]; P < .01). Finally, the stability and reliability of the results were tested using the retention method, heterogeneity test, and horizontal gene pleiotropy test. MR analysis indicates that GCA increases the risk of PMR and PMR is an important risk factor for GCA, with a causal relationship. The potential value of reasonable management of PMR in patients with GCA has received high attention. In addition, novel GCA therapeutics may be indicated for PMR, and it is a potential for further investigation.


Asunto(s)
Arteritis de Células Gigantes , Análisis de la Aleatorización Mendeliana , Polimorfismo de Nucleótido Simple , Polimialgia Reumática , Arteritis de Células Gigantes/genética , Polimialgia Reumática/genética , Humanos , Factores de Riesgo , Predisposición Genética a la Enfermedad
8.
Cereb Cortex ; 34(9)2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39315647

RESUMEN

While some studies have used a transdiagnostic approach to relate depression to metabolic or functional brain alterations, the structural substrate of depression across clinical diagnostic categories is underexplored. In a cross-sectional study of 52 patients with major depressive disorder and 51 with post-traumatic stress disorder, drug-naïve, and spanning mild to severe depression severity, we examined transdiagnostic depressive correlates with regional gray matter volume and the topological properties of gray matter-based networks. Locally, transdiagnostic depression severity correlated positively with gray matter volume in the right middle frontal gyrus and negatively with nodal topological properties of gray matter-based networks in the right amygdala. Globally, transdiagnostic depression severity correlated positively with normalized characteristic path length, a measure implying brain integration ability. Compared with 62 healthy control participants, both major depressive disorder and post-traumatic stress disorder patients showed altered nodal properties in regions of the fronto-limbic-striatal circuit, and global topological organization in major depressive disorder in particular was characterized by decreased integration and segregation. These findings provide evidence for a gray matter-based structural substrate underpinning depression, with the prefrontal-amygdala circuit a potential predictive marker for depressive symptoms across clinical diagnostic categories.


Asunto(s)
Amígdala del Cerebelo , Trastorno Depresivo Mayor , Sustancia Gris , Imagen por Resonancia Magnética , Corteza Prefrontal , Trastornos por Estrés Postraumático , Humanos , Masculino , Trastorno Depresivo Mayor/diagnóstico por imagen , Trastorno Depresivo Mayor/fisiopatología , Femenino , Trastornos por Estrés Postraumático/diagnóstico por imagen , Trastornos por Estrés Postraumático/fisiopatología , Trastornos por Estrés Postraumático/patología , Adulto , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/patología , Amígdala del Cerebelo/diagnóstico por imagen , Amígdala del Cerebelo/patología , Imagen por Resonancia Magnética/métodos , Estudios Transversales , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Persona de Mediana Edad , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/patología , Índice de Severidad de la Enfermedad , Adulto Joven
9.
Nano Lett ; 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39324741

RESUMEN

The five volt-class battery is one promising candidate of high energy density lithium-ion batteries. However, it suffers from limited electrochemical performance due to many problems, one of which is Al current collector corrosion. The corrosion greatly affects the electrochemical performance of batteries, so uncovering the Al corrosion mechanism and developing its protection strategy in the 5 V-class battery becomes important. Here, we experimentally realize a corrosion-resistant Al current collector via graphene protection. The experimental and theoretical calculation indicate that graphene can work as a physical barrier to inhibit direct contact between LiPF6-based electrolyte and an Al current collector, reducing the side reactions between Al current collector and HF originated from electrolyte. What is more, graphene increases the Al corrosion reaction potential, raising the difficulty of electrochemical corrosion. These effects improve the electrochemical performance of the 5 V-class battery, especially the rate performance and cycling stability. The work is beneficial for the development of a 5 V-class battery.

10.
JACS Au ; 4(9): 3427-3435, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39328750

RESUMEN

The utilization of structure distortion to modulate the electronic structure and alter catalytic properties of metallic nanomaterials is a well-established practice, but accurately identifying and comprehensively understanding these distortions present significant challenges. Ligand-stabilized metal nanoclusters with well-defined structures serve as exemplary model systems to illustrate the structure chemistry of nanomaterials, among which few studies have investigated nanocluster models that incorporate structural distortions. In this work, a novel copper hydride nanocluster, Cu42(PPh3)8(RS)4(CF3COO)10(CH3O)4H10 (Cu42; PPh3 is triphenylphosphine and RSH is 2,4-dichlorophenylthiol), with a highly twisted structure has been synthesized in a simple way. Structural analysis reveals Cu42 comprises two Cu25 units that are conjoined in a nearly orthogonal manner. The dramatic distortion in the metal framework, which is driven by multiple interactions from the surface ligands, endows the cluster with a rich array of uncoordinated metal sites on the surface. The resulting cluster, as envisioned, exhibits remarkable activity in catalyzing carbonylation of anilines. The findings from this study not only provides atomically precise insights into the structural distortions that are pertinent to nanoparticle catalysts but also underscores the potential of structurally distorted NCs as a burgeoning generation of catalysts with precise structures and outstanding performances that can be tailored for specific functions.

11.
Nat Commun ; 15(1): 8377, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39333081

RESUMEN

Posttranslational modifications (PTMs) of tubulin, termed the "tubulin code", play important roles in regulating microtubule functions within subcellular compartments for specialized cellular activities. While numerous tubulin PTMs have been identified, a comprehensive understanding of the complete repertoire is still underway. In this study, we report that α-tubulin lactylation is catalyzed by HDAC6 by using lactate to increase microtubule dynamics in neurons. We identify lactylation on lysine 40 of α-tubulin in the soluble tubulin dimers. Notably, lactylated α-tubulin enhances microtubule dynamics and facilitates neurite outgrowth and branching in cultured hippocampal neurons. Moreover, we discover an unexpected function of HDAC6, acting as the primary lactyltransferase to catalyze α-tubulin lactylation. HDAC6-catalyzed lactylation is a reversible process, dependent on lactate concentrations. Intracellular lactate concentration triggers HDAC6 to lactylate α-tubulin, a process dependent on its deacetylase activity. Additionally, the lactyltransferase activity may be conserved in HDAC family proteins. Our study reveals the primary role of HDAC6 in regulating α-tubulin lactylation, establishing a link between cell metabolism and cytoskeleton functions.


Asunto(s)
Citoesqueleto , Histona Desacetilasa 6 , Microtúbulos , Neuronas , Procesamiento Proteico-Postraduccional , Tubulina (Proteína) , Tubulina (Proteína)/metabolismo , Histona Desacetilasa 6/metabolismo , Histona Desacetilasa 6/genética , Animales , Microtúbulos/metabolismo , Citoesqueleto/metabolismo , Neuronas/metabolismo , Humanos , Ácido Láctico/metabolismo , Hipocampo/metabolismo , Hipocampo/citología , Ratones , Ratas , Proyección Neuronal/efectos de los fármacos , Células Cultivadas , Lisina/metabolismo
12.
Nat Commun ; 15(1): 8367, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39333136

RESUMEN

The aqueous interface-rich system has been proposed to act as a trigger and a reservoir for reactive radicals, playing a crucial role in chemical reactions. Although much is known about the redox reactivity of water microdroplets at "droplets-in-gas" interfaces, it remains poorly understood for "bubbles-in-water" interfaces that are created by feeding gas through the porous membrane of the gas diffusion electrode. Here we reveal the spontaneous generation of highly reactive redox radical species detected by using electron paramagnetic resonance under such conditions without applying any bias and loading any catalysts. In combination with ultraviolet-visible spectroscopy, the redox feature has been further verified through several probe molecules. Unexpectedly, introducing crown ether allows to isolate and stabilize both water radical cations and hydrated electrons thus substantially increasing redox reactivity. Our finding suggests a reactive microenvironment at the interface of the gas diffusion electrode owing to the coexistence of oxidative and reductive species.

13.
Sci Total Environ ; 954: 176476, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39322079

RESUMEN

As global warming intensifies, heat waves occur more frequently around the world. Heat stress from hot and humid environments poses a significant threat to human health. It can cause a significant increase in core body temperature (CBT), and even lead to life-threatening heat stroke. Extremely high CBT is considered the most important clinical symptom and prognostic indicator of heat stroke. To study it, we implanted temperature-monitoring capsules into the abdominal cavities of rats to measure their CBT values. The rats were then exposed to different hot and humid environments to monitor the resultant changes in their CBTs. The results showed that heat stress could induce a three-phase thermoregulatory response in rats under different conditions. A temperature plateau was observed as part of the three-phase thermoregulatory response, at a similar CBT across different conditions. The duration of this plateau can reflect the thermotolerance of rats in hot and humid environments. The third stage of the three-phase thermoregulatory response reflects the pathogenesis of heat stroke, which may present the key stage of heat injury. Moreover, a certain range of humidity did not affect the thermoregulatory responses of rats, but exerted a significant impact once a certain threshold was reached. In this study, the CBTs of the rats in different environments were monitored to characterize their thermoregulatory responses under heat stress. In particular, the discovery of the plateau phase and humidity threshold may help to better understand the effects of high temperature and humidity conditions on living organisms.

14.
Nat Protoc ; 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39327537

RESUMEN

O-GalNAc glycans, also known as mucin-type O-glycans, are primary constituents of mucins on various mucosal sites of the body and also ubiquitously expressed on cell surface and secreted proteins. They have crucial roles in a wide range of physiological and pathological processes, including tumor growth and progression. In addition, altered expression of O-GalNAc glycans is frequently observed during different disease states. Research dedicated to unraveling the structure-function relationships of O-GalNAc glycans has led to the discovery of disease biomarkers and diagnostic tools and the development of O-glycopeptide-based cancer vaccines. Many of these efforts require amino acid-linked O-GalNAc core structures as building blocks to assemble complex O-glycans and glycopeptides. There are eight core structures (cores one to eight), from which all mucin-type O-glycans are derived. In this protocol, we describe the first divergent synthesis of all eight cores from a versatile precursor in practical scales. The protocol involves (i) chemical synthesis of the orthogonally protected precursor (3 days) from commercially available materials, (ii) chemical synthesis of five unique glycosyl donors (1-2 days for each donor) and (iii) selective deprotection of the precursor and assembly of the eight cores (2-4 days for each core). The procedure can be adopted to prepare O-GalNAc cores linked to serine, threonine and tyrosine, which can then be utilized directly for solid-phase glycopeptide synthesis or chemoenzymatic synthesis of complex O-glycans. The procedure empowers researchers with fundamental organic chemistry skills to prepare gram scales of any desired O-GalNAc core(s) or all eight cores concurrently.

15.
Pharm Res ; 41(9): 1893-1901, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39231906

RESUMEN

PURPOSES: Size exclusion chromatography (SEC) is widely used to characterize molecular size variants of antibody drugs. However, SEC analysis is hindered by secondary interactions (or nonspecific interactions) between proteins and stationary phase packing, which result in poor column efficiency. Previous studies have reported that chaotropic salt can inhibit these interactions, but the corresponding applications of this aspect are relatively rare. Therefore, this study introduces a novel approach using sodium iodide (NaI) as a mobile-phase component in SEC and investigates the influence of the mobile-phase composition on secondary interactions. METHODS: SEC analysis was performed on one antibody-drug conjugate and four monoclonal antibodies (mAbs) using three different mobile-phase systems (i.e., sodium chloride/L-arginine hydrochloride/NaI mobile phases system) to compare the column efficiency. Subsequently, mAb-1 was used as a model to investigate the effects of these factors on secondary interactions by adjusting the ionic strength (salt concentration) and pH of the NaI mobile-phase system. RESULTS: NaI exhibits superior column efficiency performance in the SEC analysis of most products. The ionic strength will affect nonideal electrostatic and hydrophobic interaction. An appropriate ionic strength can inhibit electrostatic interactions, while an excessive ionic strength increases hydrophobic interactions. pH primarily influences electrostatic interactions. Determining the appropriate pH necessitates consideration of the isoelectric point of the protein and the pH tolerance of the column. CONCLUSIONS: In SEC analysis, using NaI as the salt component in the mobile phase reduces secondary interactions and improves column efficiency. This approach is advantageous for samples with intense secondary interactions and is a suitable alternative.


Asunto(s)
Anticuerpos Monoclonales , Cromatografía en Gel , Inmunoconjugados , Yoduro de Sodio , Anticuerpos Monoclonales/química , Cromatografía en Gel/métodos , Inmunoconjugados/química , Yoduro de Sodio/química , Concentración Osmolar , Interacciones Hidrofóbicas e Hidrofílicas , Concentración de Iones de Hidrógeno , Cloruro de Sodio/química , Electricidad Estática , Arginina/química
16.
J Org Chem ; 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39291809

RESUMEN

A series of oligothiophenes singly and doubly functionalized with dicyanorhodanine (RCN) units have been investigated to understand their Z/E photoisomerization behavior upon structural modulation. Monotopic RCN target molecules (1-Z-9-Z) were designed to observe the consequences of π-conjugation, solubilizing group substitution, and formylation of the thiophene units. In all cases, the Z isomer is obtained from synthesis as the thermodynamically stable isomer, whereas the E isomer is achieved through selective irradiation (including red light, λirr = 628 nm) as a Z/E mixture in solution. For the quarterthiophene entries, photoisomerization is inhibited, with photoirradiation resulting only in degradation. The result comports with concentration-dependent studies, which show that increasing π-conjugation results in greater aggregation and muted Z/E photoisomerization. Ditopic RCN targets (10-ZZ-12-ZZ), mimicking acceptor-donor-acceptor (A-D-A) oligomers relevant to OPV materials, also show evidence of photoisomerization in solution, with formation of Z,Z/Z,E mixtures at the photostationary state (PSS). Complementary ground- and excited-state DFT calculations show excellent agreement with the experimental findings. This comprehensive structure-property analysis is expected to both guide and caution the functional materials community with respect to the usage of photoisomerizable RCN-oligothiophenes for optoelectronic applications.

17.
J Hazard Mater ; 480: 135864, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39298968

RESUMEN

The distribution characteristics of Cr(VI) species in contaminated soil is crucial for soil remediation; however, there is currently a lack of methods for analysing anionic Cr(VI) species in soil. This study has developed a novel sequential extraction method for speciation of Cr(VI) and Cr(III). Besides extraction experiments, simulated chromium species were prepared to verify the presence of proposed chromium species. The results show that Cr(VI) species in soil can be categorized into water-soluble Cr(VI), electrostatically adsorbed Cr(VI), Cr(VI) specifically adsorbed by minerals containing exchangeable Ca2+, Cr(VI) specifically adsorbed by hydrous metal oxides, calcium chromate Cr(VI) and stable complexed adsorption Cr(VI). These Cr(VI) species can be selectively extracted by specific solutions through ion exchange or weak acid dissolution. The most stable Cr(VI) species is Cr(VI) complexed by hydrous iron oxides through bidentate ligand binding; only by dissolution of hydrous iron oxides can this Cr(VI) species be leached. The distribution of Cr(VI) species is closely linked to particular soil compositions including exchangeable Ca2+ and hydrous iron oxides which determinate the Cr(VI) adsorption in soil. Cr(III) species comprise Fe-Cr coprecipitate hydroxides Cr(III), Fe-Mn oxide-bound Cr(III), organic matter-bound Cr(III) and residual Cr(III). Their distribution depends on the types of reductants present in the soil.

18.
Placenta ; 156: 98-107, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39299215

RESUMEN

INTRODUCTION: Senescence in human amniotic epithelial cells (hAECs) and increased sterile inflammation in the amniotic cavity can lead to the initiation of term labor (TL). We investigated the possible roles of hsa-miR-3928-3p and chemokine ligand 3 (CCL3) in labor initiation and the underlying molecular mechanisms. METHODS: Microarray chip screening was used to analyse the differential expression of miRNAs in amniotic fluid exosomes from women in TL and term not-in-labor. The GEO and miRWalk databases were used to identify differential genes, and a dual luciferase assay was used to verify the relationship. Reverse transcription quantitative PCR (RT-qPCR) and immunofluorescence were used to determine the expression and localization of CCL3/CCR5 in fetal membranes. RT-qPCR and western blotting were used to detect the expression of CCL3/CCR5 in hAECs with hsa-miR-3928-3p knockdown/overexpression. Cell counting kit 8, flow cytometry, EdU proliferation, senescence-associated ß-galactosidase, and enzyme-linked immunosorbent assays were performed to detect the impact of hsa-miR-3928-3p on hAEC function. RESULTS: hsa-miR-3928-3p expression was downregulated in TL. CCL3 (macrophage inflammatory protein-1α) was identified as a differentially expressed target gene. hsa-miR-3928-3p targeted the 3' UTR of CCL3. Downregulation of hsa-miR-3928-3p expression increased CCL3 expression. CCL3, via its CCR5 receptor, decreased the proliferation, but increased the senescence, apoptosis rate, secretion of inflammatory factors (IL-8, TNF-α, and IL-6), and expression of senescence-associated protein p21 in hAECs. DISCUSSION: hsa-miR-3928-3p negatively regulates CCL3, promoting hAEC senescence through the CCL3-CCR5 axis and inducing signals for labor initiation. These findings provide novel insights for labor initiation in clinical settings.

19.
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.

20.
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
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