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1.
Wound Repair Regen ; 32(3): 301-313, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38308577

RESUMEN

Bacterial wound infection has emerged as a pivotal threat to human health worldwide, and the situation has worsened owing to the gradual increase in antibiotic-resistant bacteria caused by the improper use of antibiotics. To reduce the use of antibiotics and avoid the increase in antibiotic-resistant bacteria, researchers are increasingly paying attention to  photodynamic therapy, which uses light to produce reactive oxygen species to kill bacteria. Treating bacteria-infected wounds by photodynamic therapy requires fixing the photosensitizer (PS) at the wound site and maintaining a certain level of wound humidity. Hydrogels are materials with a high water content and are well suited for fixing PSs at wound sites for antibacterial photodynamic therapy. Therefore, hydrogels are often loaded with PSs for treating bacteria-infected wounds via antibacterial photodynamic therapy. In this review, we systematically summarised the antibacterial mechanisms and applications of PS-loaded hydrogels for treating bacteria-infected wounds via photodynamic therapy. In addition, the recent  studies and the research status progresses of novel antibacterial hydrogels are discussed. Finally, the challenges and future prospects of PS-loaded hydrogels are reviewed.


Asunto(s)
Antibacterianos , Vendajes , Hidrogeles , Fármacos Fotosensibilizantes , Infección de Heridas , Humanos , Antibacterianos/farmacología , Antibacterianos/administración & dosificación , Infecciones Bacterianas/tratamiento farmacológico , Hidrogeles/farmacología , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Cicatrización de Heridas/efectos de los fármacos , Infección de Heridas/tratamiento farmacológico , Infección de Heridas/microbiología
2.
Zhongguo Zhong Yao Za Zhi ; 49(4): 884-893, 2024 Feb.
Artículo en Zh | MEDLINE | ID: mdl-38621895

RESUMEN

Sepsis is a systemic inflammatory response syndrome caused by infection, with high morbidity and mortality. Sepsis-induced liver injury(SILI) is one of the manifestations of sepsis-induced multiple organ syndrome. At present, there is no recommended pharmacological intervention for the treatment of SILI. traditional Chinese medicine(TCM), based on the holism and dialectical treatment concept, shows the therapeutic characteristics of multi-target and multi-pathway and can comprehensively prevent and treat SILI by interfering with inflammatory factors, inflammatory signaling pathways, and anti-oxidative stress and inhibiting apoptosis. This article reviewed the experimental studies on the treatment of SILI with TCM to clarify its pathogenic mechanism and therapeutic characteristics, so as to provide more ideas and directions for the development or preparation of new drugs.


Asunto(s)
Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Medicamentos Herbarios Chinos , Sepsis , Humanos , Medicina Tradicional China , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/tratamiento farmacológico , Sepsis/complicaciones , Sepsis/tratamiento farmacológico , Apoptosis , Transducción de Señal , Medicamentos Herbarios Chinos/uso terapéutico , Medicamentos Herbarios Chinos/farmacología
3.
New Phytol ; 240(2): 515-528, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37532958

RESUMEN

Plant roots are the main supplier of carbon (C) to the soil, the largest terrestrial C reservoir. Soil pore structure drives root growth, yet how it affects belowground C inputs remains a critical knowledge gap. By combining X-ray computed tomography with 14 C plant labelling, we identified root-soil contact as a previously unrecognised influence on belowground plant C allocations and on the fate of plant-derived C in the soil. Greater contact with the surrounding soil, when the growing root encounters a pore structure dominated by small (< 40 µm Ø) pores, results in strong rhizodeposition but in areas of high microbial activity. The root system of Rudbeckia hirta revealed high plasticity and thus maintained high root-soil contact. This led to greater C inputs across a wide range of soil pore structures. The root-soil contact Panicum virgatum, a promising bioenergy feedstock crop, was sensitive to the encountered structure. Pore structure built by a polyculture, for example, restored prairie, can be particularly effective in promoting lateral root growth and thus root-soil contact and associated C benefits. The findings suggest that the interaction of pore structure with roots is an important, previously unrecognised, stimulus of soil C gains.


Asunto(s)
Panicum , Suelo , Suelo/química , Carbono/análisis , Raíces de Plantas/química , Tomografía Computarizada por Rayos X
4.
Langmuir ; 39(2): 851-861, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36599647

RESUMEN

Solid-supported ionic liquid catalysts (SILs) are the simplest form of a heterogenized ionic liquid and have attracted soaring attention because of the high catalytic activity as well as separation. Unfortunately, instability severely hinders their practical application, and the reason for the deactivation of SILs has not been investigated in detail. In the present study, the immobilized ionic liquid catalysts MIL-101-[IA-SO3H][HSO4] and MIL-101-[IA-COOH][HSO4] were prepared and used to study the stability in the esterification reaction. The results show that compared with MIL-101-[IA-COOH][HSO4], MIL-101-[IA-SO3H][HSO4] has a higher catalytic activity and a lower stability. The deactivation mechanism is discussed based on experiments and theoretical analysis: the protons on -SO3H dissociate in a polar solvent and combine with anion HSO4-, and then, the formative H2SO4 molecule will leach out into the solvent. Our discussion indicates that the stability of immobilized ionic liquids is determined by the substituents of ionic liquid cations and becomes the significant factor controlling the stability limits. The study presented here would be important for understanding the deactivation reason and can help in choosing the suitable cation to avoid leaching of the active site during the reaction.

5.
Cerebrovasc Dis ; 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37722359

RESUMEN

INTRODUCTION: The correlation between diabetes and stroke has been studied extensively in epidemiological research. Here we used bibliometric software to visualize and analyze the literature related to diabetic stroke to provide an overview of the current state of research, hot spots, and future trends in the field. METHODS: Based on the Web of Science Core Collection(WoSCC) database, we collected studies related to diabetic stroke from 2007 to May 2022. We used CiteSpace (version 6.1.R5), VOSviewer, and Sci-mago Graphica to create knowledge maps and conduct visual analyses on authors, countries, in-stitutions, cited references, and keywords, and Origin for statistical analysis. RESULTS: We included a total of 5171 papers on diabetic stroke from the WoSCC database. Overall, there was a steady increase in the number of publications, with a high number of emerging scientists. The United States was the most productive and influential country, which dominated national col-laborations. The most common subject category was "neurology". In total, 12 major clusters were generated from the cited references. Keywords analysis showed that keywords related to post-stroke injury and treatment are those with the highest burst intensity and latest burst time. CONCLUSIONS: Individual disease treatment remains a hot topic and how to balance acute stroke treatment and glycemic control is currently a difficult clinical problem. At the same time, the mechanism of their interaction and the prevention and treatment of related causative factors remain a hot topic of current and future research.

6.
Environ Res ; 216(Pt 4): 114838, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36402188

RESUMEN

The immobilization of cadmium (Cd(II)) in soil using calcined rectorite (REC) was investigated in this research. The results of immobilization show that a small amount of REC calcined at 700 °C (REC-700 °C) could effectively immobilize 90% of Cd(II) in soil, while the immobilization efficiency of REC only reached 42%. Moreover, the immobilization efficiency of REC calcined at 300 °C and 500 °C (REC-300 °C and REC-500 °C) were lower than REC. To investigate the mechanism, the materials before and after immobilization were fully analyzed by Fourier transform infrared spectroscopy (FT-IR), powdery X-ray diffraction analysis (XRD), and scanning electron microscopy (SEM). The results indicate that the structure of REC has been changed after calcination at different temperatures and Cd(II) was successfully immobilized on materials. Losing free water, structural water and OH groups respectively, the layer spacing of REC-300 °C and REC-500 °C was shrunk. However, the crystal structure of REC was destroyed after calcination at 700 °C, resulting in the generation of new phases. According to the XRD result, more cadmium hydroxide (Cd(OH)2) were produced on REC-700 °C, indicating that more OH groups were formed during immobilization. Furthermore, Tessier test demonstrates that Cd(II) in soil changed from exchangeable state and water soluble state to carbonate bound state and iron manganese oxide bound state during immobilization. The result of microbial community indicates that REC-700 °C can restore the microbial composition of Cd(II)-contaminated soil. The effects of pH, freeze-thaw, REC dosage, and initial heavy metal concentration were also evaluated to provide a theoretical basis for the subsequent application of the material in the remediation of contaminated soil.


Asunto(s)
Cadmio , Contaminantes del Suelo , Cadmio/análisis , Suelo/química , Contaminantes del Suelo/análisis , Temperatura , Espectroscopía Infrarroja por Transformada de Fourier , Agua/análisis
7.
Entropy (Basel) ; 25(11)2023 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-37998252

RESUMEN

Based on authorized patents of China's artificial intelligence industry from 2013 to 2022, this paper constructs an Industry-University-Research institution (IUR) collaboration network and an Inter-Firm (IF) collaboration network and used the entropy weight method to take both the quantity and quality of patents into account to calculate the innovation performance of firms. Through the hierarchical clustering algorithm and classification and regression trees (CART) algorithm, in-depth analysis has been conducted on the intricate non-linear influence mechanisms between multiple variables and a firm's innovation performance. The findings indicate the following: (1) Based on the network centrality (NC), structural hole (SH), collaboration breadth (CB), and collaboration depth (CD) of both IUR and IF collaboration networks, two types of focal firms are identified. (2) For different types of focal firms, the combinations of network characteristics affecting their innovation performance are various. (3) In the IUR collaboration network, focal firms with a wide range of heterogeneous collaborative partners can obtain high innovation performance. However, focal firms in the IF collaboration network can achieve the same aim by maintaining deep collaboration with other focal firms. This paper not only helps firms make scientific decisions for development but also provides valuable suggestions for government policymakers.

8.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 52(3): 285-295, 2023 Jun 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-37476940

RESUMEN

OBJECTIVES: To design and prepare silk fibroin/hyaluronic acid composite hydrogel. METHODS: The thiol modified silk fibroin and the double-bond modified hyaluronic acid were rapidly cured into gels through thiol-ene click polymerization under ultraviolet light condition. The grafting rate of modified silk fibroin and hyaluronic acid was characterized by 1H NMR spectroscopy; the gel point and the internal microstructure of hydrogels were characterized by rheological test and scanning electron microscopy; the mechanical properties were characterized by compression test; the swelling rate and degradation rate were determined by mass method. The hydrogel was co-cultured with the cells, the cytotoxicity was measured by the lactate dehydrogenase method, the cell adhesion was measured by the float count method, and the cell growth and differentiation on the surface of the gel were observed by scanning electron microscope and fluorescence microscope. RESULTS: The functional group substitution degrees of modified silk fibroin and hyaluronic acid were 17.99% and 48.03%, respectively. The prepared silk fibroin/hyaluronic acid composite hydrogel had a gel point of 40-60 s and had a porous structure inside the gel. The compressive strength was as high as 450 kPa and it would not break after ten cycles. The water absorption capacity of the composite hydrogel was 4-10 times of its own weight. Degradation experiments showed that the hydrogel was biodegradable, and the degradation rate reached 28%-42% after 35 d. The cell biology experiments showed that the cytotoxicity of the composite gel was low, the cell adhesion was good, and the growth and differentiation of the cells on the surface of the gel were good. CONCLUSIONS: The photocurable silk fibroin/hyaluronic acid composite hydrogel can form a gel quickly, and has excellent mechanical properties, adjustable swelling rate and degradation degree, good biocompatibility, so it has promising application prospects in biomedicine.


Asunto(s)
Fibroínas , Fibroínas/química , Hidrogeles/química , Ácido Hialurónico/química , Materiales Biocompatibles/química , Química Clic , Compuestos de Sulfhidrilo , Seda/química
9.
J Exp Bot ; 73(19): 6916-6930, 2022 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-35867472

RESUMEN

The resistance of weeds to herbicides poses a major threat to agricultural production, and non-target-site resistance (NTSR) is often a serious problem as its mechanisms can in some cases confer resistance to herbicides with different modes of action. In this study, we hypothesized that bZIP transcription factors (TFs), which regulate abiotic stress responses in many plants, play a regulatory role in NTSR. Whole-plant assays indicated that the wild grasses Echinochloa crus-galli and E. glabrescens are resistant to the herbicides penoxsulam, cyhalofop-butyl, and quintrione. Transcriptome sequencing then identified 101 and 49 bZIP TFs with differential expression following penoxsulam treatment in E. crus-galli and E. glabrescens, respectively. Twelve of these genes had >60% homology with rice genes. The expression of bZIP88 was considerably up-regulated 6 h after treatment with the three different herbicides, and it was similar between resistant and susceptible populations; however, the relative expression levels before herbicide treatment and 24 h after were the same. We used rice (Oryza sativa ssp. japonica cv Nipponbare) as a model system for functional validation and found that CRISPR-Cas9-knockout of the rice bZIP88 ortholog increased the sensitivity to herbicide, whereas overexpression reduced it. The OsbZIP88 protein was localized to the nucleus. Using ChIP coupled with high-throughput sequencing, OsbZIP88 was found to form a network regulatory center with other TFs such as bZIP20/52/59 to regulate OsKS1, OsCOE1, and OsIM1, which are related to auxin, abscisic acid, brassinosteroids, and gibberellic acid. Based on these results, we have established a database of bZIP TFs corresponding to herbicide stress, and resolved the mechanisms of the positive regulation of herbicide resistance by bZIP88, thereby providing new insights for NTSR.


Asunto(s)
Echinochloa , Herbicidas , Oryza , Echinochloa/genética , Echinochloa/metabolismo , Herbicidas/farmacología , Factores de Transcripción/metabolismo , Regulación hacia Arriba , Resistencia a los Herbicidas/genética , Oryza/genética , Oryza/metabolismo
10.
Pestic Biochem Physiol ; 182: 105038, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35249656

RESUMEN

Echinochloa crus-galli L., a notorious weed in rice paddy fields, is usually kept under control by mefenacet application at the pre-emergence or early post-emergence stage. Due to continuous and repeated usage, E. crus-galli is developing resistance to mefenacet in China. Two putative resistant and one susceptible E. crus-galli populations were collected from paddy fields in Jiangsu Province to characterize their herbicide resistance. Compared with the susceptible population, the two mefenacet-resistant populations had 2.8- and 4.1-times greater pre-emergence resistance, and 10- and 6.8-times greater early post-emergence resistance to mefenacet. These mefenacet-resistant E. crus-galli populations also exhibited cross- or multiple-resistance to acetochlor, pyraclonil, imazamox, and quinclorac. However, when the glutathione S-transferase (GST) inhibitor 4-chloro-7-nitrobenzoxadiazole (NBD-Cl) was applied prior to post-emergence treatment, mefenacet resistance levels were reduced in both populations. Additionally, GST activity in vivo in one resistant population was much higher than the susceptible population after mefenacet application. The very long chain fatty acid elongases (VLCFAEs) from both mefenacet-resistant populations required much higher mefenacet concentration to inhibit their activity. The reduced sensitivity of VLCFAEs to mefenacet indicates the presence of a target-site resistance mechanism and induction of high GST activity may provide additional contribution to E. crus-galli mefenacet resistance through a non-target-site mechanism.


Asunto(s)
Echinochloa , Herbicidas , Acetanilidas , Benzotiazoles , Resistencia a los Herbicidas , Herbicidas/farmacología
13.
Pestic Biochem Physiol ; 128: 10-5, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26969434

RESUMEN

Experiments were conducted to confirm imazethapyr resistance in redroot amaranth (Amaranthus retroflexus L.) and study the target-site based mechanism for the resistance. Whole-plant response experiments revealed that the resistant (R) population exhibited 19.16 fold resistance to imazethapyr compared with the susceptible (S) population. In vitro ALS activity assay demonstrated that the imazethapyr I50 value of the R population was 21.33 times greater than that of the S population. However, qRT-PCR analysis revealed that there is no difference in ALS gene expression between the R and S populations. Sequence analysis revealed an Asp-376-Glu substitution in ALS in the R population. In order to verify that the imazethapyr resistance was conferred by Asp-376-Glu mutation, the ALS-R and ALS-S genes were fused to the CaMV 35S promoter and introduced into Arabidopsis respectively. The expression of ALS-R in transgenic Arabidopsis plants exhibited 13.79 fold resistance to imazethapyr compared to ALS-S transgenic Arabidopsis.


Asunto(s)
Amaranthus/efectos de los fármacos , Ácidos Nicotínicos/farmacología , Amaranthus/genética , Relación Dosis-Respuesta a Droga , Expresión Génica , Plantas Modificadas Genéticamente
14.
Planta ; 242(4): 859-68, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25998526

RESUMEN

MAIN CONCLUSION: Field-evolved resistance of goosegrass to glyphosate is due to double or single mutation in EPSPS , or amplification of EPSPS leads to increased transcription and protein levels. Glyphosate has been used widely in the south of China. The high selection pressure from glyphosate use has led to the evolution of resistance to glyphosate in weeds. We investigated the molecular mechanisms of three recently discovered glyphosate-resistant Eleusine indica populations (R1, R2 and R3). The results showed that R1 and R2 had double Thr102Ile and Pro106Ser mutation and a single mutation of Pro106Leu in the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene, respectively. Escherichia coli containing the mutated EPSPS genes was tolerant to glyphosate. EPSPS activity in R1 and R2 plants was higher than in the sensitive plants. There was no amino acid substitution in EPSPS gene in R3. However, expression of EPSPS in R3 plants was higher than in glyphosate-susceptible (S) population (13.8-fold) after glyphosate treatment. EPSPS enzyme activity in both R3 and S plants was inhibited by glyphosate, while shikimate accumulation in R3 was significantly lower than for the S population. Further analysis revealed that the genome of R3 contained 28.3-fold more copies of the EPSPS gene than that of susceptible population. EPSPS expression was positively correlated with copy number of EPSPS. In conclusion, mutation of the EPSPS gene and increased EPSPS expression are part of the molecular mechanisms of resistance to glyphosate in Eleusine indica.


Asunto(s)
3-Fosfoshikimato 1-Carboxiviniltransferasa/genética , Eleusine/genética , Genes de Plantas , Glicina/análogos & derivados , Resistencia a los Herbicidas/genética , Herbicidas , Mutación , Eleusine/metabolismo , Regulación Enzimológica de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Ácido Shikímico/metabolismo , Glifosato
15.
Pestic Biochem Physiol ; 124: 43-7, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26453229

RESUMEN

Three putative resistant Amaranthus retroflexus L. populations were collected in Heilongjiang province in China. Whole plant bioassays indicated high resistance (RI > 10) to imazethapyr in the three populations. In vitro acetolactate synthase (ALS) assays revealed that ALS from populations H3, H17 and H39 was less sensitive to imazethapyr inhibition compared to the susceptible population H76. The half-maximal inhibitory concentration (I50) values for H3, H17 and H39 were 14.83, 15.27 and 268 times greater, respectively, than that of the susceptible population H76. Three nucleotide mutations resulted in three known resistance-endowing amino acid substitutions, Ala-205-Val, Trp-574-Leu and Ser-653-Thr in the three resistant populations respectively. Therefore, ALS target-site mutations in resistant A. retroflexus could be responsible for imazethapyr resistance.


Asunto(s)
Acetolactato Sintasa/metabolismo , Amaranthus/efectos de los fármacos , Amaranthus/enzimología , Herbicidas/toxicidad , Ácidos Nicotínicos/toxicidad , Acetolactato Sintasa/genética , Amaranthus/genética , China , Resistencia a los Herbicidas/genética
16.
Mol Biol Rep ; 41(4): 2077-84, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24413996

RESUMEN

5-Enolpyruvylshikimate-3-phosphate synthase (EPSPS), the target enzyme for glyphosate inhibition, catalyzes an essential step in the shikimate pathway for aromatic amino acid biosynthesis. The full-length cDNA of 1,751 nucleotides (CaEPSPS, Genbank accession number: EU698030) from Convolvulus arvensis was cloned and characterized. The CaEPSPS encodes a polypeptide of 520 amino acids with a calculated molecular weight of 55.5 kDa and an isoelectric point of 7.05. The results of homology analysis revealed that CaEPSPS showed highly homologous with EPSPS proteins from other plant species. Tissue expression pattern analysis indicated that CaEPSPS was constitutively expressed in stems, leaves and roots, with lower expression in roots. CaEPSPS expression level could increase significantly with glyphosate treatment, and reached its maximum at 24 h after glyphosate application. We fused CaEPSPS to the CaMV 35S promoter and introduced the chimeric gene into Arabidopsis. The resultant expression of CaEPSPS in transgenic Arabidopsis plants exhibited enhanced tolerance to glyphosate in comparison with control.


Asunto(s)
3-Fosfoshikimato 1-Carboxiviniltransferasa/genética , Clonación Molecular , Convolvulus/genética , Regulación de la Expresión Génica de las Plantas , 3-Fosfoshikimato 1-Carboxiviniltransferasa/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Convolvulus/clasificación , Convolvulus/metabolismo , ADN Complementario/química , ADN Complementario/genética , Resistencia a Medicamentos/genética , Activación Enzimática , Perfilación de la Expresión Génica , Glicina/análogos & derivados , Glicina/farmacología , Herbicidas/farmacología , Datos de Secuencia Molecular , Fenotipo , Filogenia , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , Alineación de Secuencia , Glifosato
17.
J Cell Biol ; 223(3)2024 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-38381149

RESUMEN

The annulus, a septin-based structure in vertebrate sperm connecting the MP and PP, has unclear migration mechanics. In this issue, Hoque et al. (https://doi.org/10.1083/jcb.202307147) report that the CBY3/CIBAR1 complex ensures its precise positioning by regulating membrane properties.


Asunto(s)
Centriolos , Flagelos , Semen , Animales , Masculino , Septinas , Ratones
18.
Expert Opin Investig Drugs ; : 1-14, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38978286

RESUMEN

INTRODUCTION: Abdominal aortic aneurysm is a progressive, segmental, abdominal aortic dilation associated with a high mortality rate. Abdominal aortic aneurysms with diameters larger than 55 mm are associated with a high risk of rupture, and the most effective treatment options are surgical repair. Close observation and lifestyle adjustments are recommended for smaller abdominal aortic aneurysms with lower rupture risk. The development of medical therapies that limit or prevent the progression, expansion, and eventual rupture of abdominal aortic aneurysms remains an unmet clinical need. AREAS COVERED: This review provides an overview of completed and ongoing clinical trials examining the efficacies of various drug classes, including antibiotics, antihypertensive drugs, hypolipidemic drugs, hypoglycemic drugs, and other potential therapies for abdominal aortic aneurysms. A search of PubMed, Web of Science, Clinical Trials, and another six clinical trial registries was conducted in January 2024. EXPERT OPINION: None of the drugs have enough evidence to indicate that they can effectively inhibit the dilation of abdominal aortic aneurysm. More clinical trial data is required to support the efficacy of propranolol. Future research should also explore different drug delivery mechanisms, such as nanoparticles, to elevate drug concentration at the aneurysm wall.

19.
J Hazard Mater ; 465: 132977, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38008052

RESUMEN

Freeze-thaw cycles (FTCs) cause dynamic microscale changes in ions and solvents. During freezing, heavy metals adsorbed on zero-valent iron (M-ZVI) and protons are excluded by ice crystals and concentrated in the liquid-like grain boundary region. The high proton concentration in this region leads to the dissolution of the passivation layer of ZVI. To assess the environmental risks of M-ZVI during FTCs, this study evaluated the stability of M-ZVI in this scenario from both microscale and macroscale perspectives. The results showed that the dissolution of the passivation layer had a dual effect on the stability of M-ZVI, which depends on the by-products of M-ZVI. The dissolution of the passivation layer was accompanied by the leaching of heavy metals, such as Ni-ZVI, but it also enhanced the reactivity of ZVI, causing it to re-react with desorbed heavy metals. The stability of Cr-ZVI and Cd-ZVI was improved due to frequent FTCs. Furthermore, changes in the surrounding environment (water dipole moment, ion concentration, etc.) of ZVI affected the crystallization of Fe oxides, increasing the content of amorphous Fe oxide. As low-crystallinity Fe oxides could facilitate ion doping, Ni2+ was doped into Fe3O4 lattice during FTCs, which reduced the mobility of heavy metals. Contrary to traditional views that freezing temperatures slow chemical reactions, this study provides new insights into the application of iron-based materials in cold environments.

20.
Exp Gerontol ; 194: 112505, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38964432

RESUMEN

BACKGROUND: Genome-wide association studies (GWAS) have revealed numerous loci associated with multiple sclerosis (MS). However, the challenge lies in deciphering the mechanisms by which these loci influence the target traits. Here, we employed an integrative analytical pipeline to efficiently transform genetic associations to identify novel proteins for MS. METHODS: We systematically integrated MS GWAS data (N = 115,803) with human plasma proteome data (N = 7213) and conducted proteome-wide association studies (PWAS) to identify MS-associated pathogenic proteins. Following this, we employed Mendelian randomization and Bayesian colocalization analyses to verify the causal relationship between these significant plasma proteins and MS. Lastly, we utilized the Drug-Gene Interaction Database (DGIdb) to identify potential drug targets for MS. RESULTS: The PWAS identified 25 statistically significant cis-regulated plasma proteins associated with MS at a false discovery rate of P < 0.05. Further analysis revealed that the abundance of 7 of these proteins (PLEK, TNXB, CASP3, CD59, CR1, TAPBPL, ATXN3) was causally related to the incidence of MS. Our findings indicated that genetically predicted higher levels of TNXB and CD59 were associated with a lower risk of MS, whereas higher levels of PLEK, CASP3, CR1, TAPBPL, and ATXN3 were associated with an increased risk of MS. Three plasma proteins (PLEK, CR1, CD59) were validated by colocalization analysis. Among these, CR1 was prioritized as a target for Eculizumab due to its significant association with MS risk. Additionally, PLEK, CR1, and CD59 were identified as druggable target genes. CONCLUSIONS: Our proteomic analysis has identified PLEK, CR1, and CD59 as potential drug targets for MS treatment. Developing pharmacological inducers or inhibitors for these proteins could pave the way for new therapeutic approaches, potentially improving outcomes for MS patients.

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