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1.
Carbohydr Polym ; 335: 122101, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38616079

RESUMO

In this study, we purified a partially acetylated heteropolysaccharide (Ts1-1A) from the fruit bodies of Trametes sanguinea Lloyd through cold water extraction and serial chromatographic separation. The purified polysaccharide Ts1-1A (12.8 kDa) was characterized as a branched mannogalactofucan with a backbone of alternately connected 1,3-linked α-Fucp and 1,6-linked α-Galp, which was partially substituted by non-reducing end units of ß-Manp at O-2 and O-3 positions of 1,6-linked α-Galp. Ts1-1A showed pronounced anti-human cytomegalovirus activity at the concentration of 200 and 500 µg/mL in systematical assessments including morphological changes, western blotting, qPCR, indirect immunofluorescence and tissue culture infective dose assays. Moreover, Ts1-1A exerted its antiviral activity at two distinct stages of viral proliferation manifesting as significantly inhibiting viral protein (IE1/2 and p52) expression and reducing viral gene (UL123, UL44 and UL32) replication in the HCMV-infected WI-38 cells. At viral attachment stage, Ts1-1A interacted with HCMV and prevented HCMV from attaching to its host cells. While at early phase of viral replication stage, Ts1-1A suppressed HCMV replication by downregulating NQO1 and HO-1 proteins related to oxidative stress as an antioxidant. To sum up, Ts1-1A is a promising anti-HCMV agent which could be developed for HCMV infection prevention and therapy.


Assuntos
Citomegalovirus , Polyporaceae , Humanos , Trametes , Antivirais/farmacologia
2.
Natl Sci Rev ; 11(4): nwae063, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38623453

RESUMO

The Chinese Bayan Obo deposit is a world-class rare earth element (REE) deposit with considerable niobium (Nb) and iron (Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead (U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites-key Nb-bearing minerals-are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma (n = 99), 438 ± 7 Ma (n = 93), and 268 ± 5 Ma (n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

3.
Biomacromolecules ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608139

RESUMO

Over decades of development, while phosphoramidite chemistry has been known as the leading method in commercial synthesis of oligonucleotides, it has also revolutionized the fabrication of sequence-defined polymers (SDPs), offering novel functional materials in polymer science and clinical medicine. This review has introduced the evolution of phosphoramidite chemistry, emphasizing its development from the synthesis of oligonucleotides to the creation of universal SDPs, which have unlocked the potential for designing programmable smart biomaterials with applications in diverse areas including data storage, regenerative medicine and drug delivery. The key methodologies, functions, biomedical applications, and future challenges in SDPs, have also been summarized in this review, underscoring the significance of breakthroughs in precisely synthesized materials.

5.
Int Immunopharmacol ; 133: 112080, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38613882

RESUMO

Myocardial infarction leads to myocardial inflammation and apoptosis, which are crucial factors leading to heart failure and cardiovascular dysfunction, eventually resulting in death. While the inhibition of AMPA receptors mitigates inflammation and tissue apoptosis, the effectiveness of this inhibition in the pathophysiological processes of myocardial infarction remains unclear. This study investigated the role of AMPA receptor inhibition in myocardial infarction and elucidated the underlying mechanisms. This study established a myocardial infarction model by ligating the left anterior descending branch of the coronary artery in Sprague-Dawley rats. The findings suggested that injecting the AMPA receptor antagonist NBQX into myocardial infarction rats effectively alleviated cardiac inflammation, myocardial necrosis, and apoptosis and improved their cardiac contractile function. Conversely, injecting the AMPA receptor agonist CX546 into infarcted rats exacerbated the symptoms and tissue damage, as reflected by histopathology. This agonist also stimulated the TLR4/NF-κB pathway, further deteriorating cardiac function. Furthermore, the investigations revealed that AMPA receptor inhibition hindered the nuclear translocation of P65, blocking its downstream signaling pathway and attenuating tissue inflammation. In summary, this study affirmed the potential of AMPA receptor inhibition in countering inflammation and tissue apoptosis after myocardial infarction, making it a promising therapeutic target for mitigating myocardial infarction.

8.
Food Res Int ; 184: 114258, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38609236

RESUMO

The study aimed to determine the chemical structures of octadecatrienoic acid isomers produced by probiotics through the bioconversion of α-linolenic acid and to assess their antioxidant capacities. The chemical structures were identified using nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS), while the antioxidant capacities were evaluated in vitro and in cellular. The NMR signals obtained allowed for definitive characterization, with the main ion fragments detected being m/z 58.0062, 59.0140, 71.0141, 113.0616, 127.0777, and 181.5833. Compounds at concentrations below 40 µM maintained the antioxidant capacity of HepG2 cells by protecting endogenous antioxidative enzymes and mitochondrial membrane potential. However, doses higher than 40 µM increase oxidative damage and mitochondrial dysfunction. These results confirmed the structure of the probiotic-derived compound as trans9, trans11, cis15-conjugated linolenic acid. Additionally, appropriate doses of CLNA can alleviate oxidative stress induced by AAPH, while high doses aggravate cellular damage. These findings provide foundational information for the further exploration of probiotic-derived edible lipids.


Assuntos
Antioxidantes , Lomustina/análogos & derivados , Probióticos , Antioxidantes/farmacologia , Ácido alfa-Linolênico , Estresse Oxidativo
9.
Acta Pharm Sin B ; 14(4): 1508-1524, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38572110

RESUMO

Macrophage senescence, manifested by the special form of durable cell cycle arrest and chronic low-grade inflammation like senescence-associated secretory phenotype, has long been considered harmful. Persistent senescence of macrophages may lead to maladaptation, immune dysfunction, and finally the development of age-related diseases, infections, autoimmune diseases, and malignancies. However, it is a ubiquitous, multi-factorial, and dynamic complex phenomenon that also plays roles in remodeled processes, including wound repair and embryogenesis. In this review, we summarize some general molecular changes and several specific biomarkers during macrophage senescence, which may bring new sight to recognize senescent macrophages in different conditions. Also, we take an in-depth look at the functional changes in senescent macrophages, including metabolism, autophagy, polarization, phagocytosis, antigen presentation, and infiltration or recruitment. Furthermore, some degenerations and diseases associated with senescent macrophages as well as the mechanisms or relevant genetic regulations of senescent macrophages are integrated, not only emphasizing the possibility of regulating macrophage senescence to benefit age-associated diseases but also has an implication on the finding of potential targets or drugs clinically.

10.
Chem Commun (Camb) ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38577766

RESUMO

Herein, we report a copper(I)-free method for labeling the trifluoroacetyl group with positron-emitting carbon-11 (t1/2 = 20.4 min) or fluorine-18 (t1/2 = 109.8 min) as part of our exploration of radiolabeled fluoroforms to access new radiolabeled chemotypes of interest for tracer development. Treatment of alkyl esters and aryl esters, containing electron-donating or electron-withdrawing groups, with [11C/18F]fluoroform in the presence of strong base, gave [11C/18F]trifluoromethyl ketones as novel radiolabeling synthons in moderate to high yields within 15 minutes.

11.
Opt Lett ; 49(7): 1832-1835, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38560876

RESUMO

We propose a novel, to the best of our knowledge, approach to realizing instantaneous frequency measurement with ultrahigh measurement bandwidth, which utilizes three-channel photonic compressive sensing (CS) with sub-Nyquist pseudo-random binary sequences (PRBSs). In each CS channel, an alias frequency is recovered due to the sub-Nyquist property of the applied PRBS. A frequency identification algorithm is employed to determine the frequency of the signal under measurement according to the three alias frequencies. The proposed approach significantly reduces the bit rate of the applied PRBSs and the sampling rate required by the digitizers in CS. A proof-of-concept experiment for measuring frequency in the Ku band is demonstrated using PRBSs at 1 Gb/s and digitizers with a sampling rate of 250 MS/s.

12.
Psychol Med ; : 1-12, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563297

RESUMO

BACKGROUND: Despite extensive research into the neural basis of autism spectrum disorder (ASD), the presence of substantial biological and clinical heterogeneity among diagnosed individuals remains a major barrier. Commonly used case‒control designs assume homogeneity among subjects, which limits their ability to identify biological heterogeneity, while normative modeling pinpoints deviations from typical functional network development at individual level. METHODS: Using a world-wide multi-site database known as Autism Brain Imaging Data Exchange, we analyzed individuals with ASD and typically developed (TD) controls (total n = 1218) aged 5-40 years, generating individualized whole-brain network functional connectivity (FC) maps of age-related atypicality in ASD. We then used local polynomial regression to estimate a networkwise normative model of development and explored correlations between ASD symptoms and brain networks. RESULTS: We identified a subset exhibiting highly atypical individual-level FC, exceeding 2 standard deviation from the normative value. We also identified clinically relevant networks (mainly default mode network) at cohort level, since the outlier rates decreased with age in TD participants, but increased in those with autism. Moreover, deviations were linked to severity of repetitive behaviors and social communication symptoms. CONCLUSIONS: Individuals with ASD exhibit distinct, highly individualized trajectories of brain functional network development. In addition, distinct developmental trajectories were observed among ASD and TD individuals, suggesting that it may be challenging to identify true differences in network characteristics by comparing young children with ASD to their TD peers. This study enhances understanding of the biological heterogeneity of the disorder and can inform precision medicine.

13.
Funct Integr Genomics ; 24(2): 71, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38568332

RESUMO

The incidence rate of developing ovarian cancer decreases over the years; however, mortality ranks top among malignancies of women, mainly metastasis through local invasion. Matrilin-2 (MATN2) is a member of the matrilin family that plays an important role in many cancers. However, its relationship with ovarian cancer remains unknown. Our study aimed to explore the function and possible mechanism of MATN2 in ovarian cancer. Human ovarian cancer tissue microarrays were used to detect the MATN2 expression in different types of ovarian cancer using immunohistochemistry (IHC). CCK-8, wound scratch healing assay, transwell assay, and flow cytometry were used to detect cell mobility. Gene and protein expression were detected using quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting. MATN2 interacts with phosphatase, and the tensin homolog (PTEN) deleted on chromosome 10 was analyzed using TCGA database and co-immunoprecipitation (Co-IP). In vivo experiments were conducted using BALB/c nude mice, and tumor volume and weight were recorded. Tumor growth was determined using hematoxylin and eosin (H&E) and IHC staining. MATN2 was significantly downregulated in ovarian cancer cells. The SKOV3 and A2780 cell mobility was significantly inhibited by MATN2 overexpression, while the cell apoptosis rate was significantly increased. MATN2 overexpression decreased transplanted tumor size in vivo. These results were reversed by inhibiting MATN2. Furthermore, we found that PTEN closely interacted with MATN2 using bioinformatics and Co-IP. MATN2 overexpression significantly inhibited the PI3K/AKT pathway, however, PTEN suppression reversed this effect of MATN2 overexpression. These results indicated that MATN2 may play a critical role in ovarian cancer development by inhibiting cells proliferation and migration. The mechanism was related to interacting with PTEN, thus inhibiting downstream effectors in the PI3K/AKT pathway, which may be a novel target for treating ovarian cancer.


Assuntos
Neoplasias Ovarianas , Animais , Camundongos , Feminino , Humanos , Neoplasias Ovarianas/genética , Proteínas Matrilinas , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Linhagem Celular Tumoral , Camundongos Nus , PTEN Fosfo-Hidrolase/genética
14.
Opt Express ; 32(6): 9095-9104, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571150

RESUMO

For optical interconnect applications, multi-wavelength comb sources require uniform comb spacings and high reliability at high operating temperature. Here, the high-temperature reliability measurements of a InAs quantum dot colliding pulse mode-locked (QD-CPML) laser with 100 GHz comb spacing are systematically investigated. Laser lifetime measurements are performed for over 1600 hours at 80 °C under constant stress current of 150 mA. The mean time to failure (MTTF) of the laser is approximately 38 years (336,203 hours), extracted from the threshold currents extrapolation method. The optical spectral revolutions are also monitored during the aging process, while the grids of comb laser are remarkably stable. The outstanding reliability and spectrum stability make this 100 GHz QD-CPML a promising candidate as a multi-wavelength laser source for datacom and optical I/O applications.

15.
Front Microbiol ; 15: 1364339, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559355

RESUMO

Introduction: Matrine (MT) is a potential resistance reversal agent. However, it remains unclear whether MT can reverse the resistance of Haemophilus parasuis (H. parasuis) to ß-lactams, and, if so, by what mechanism MT works. Methods: We screened one cefaclor (CEC)-resistant strain (clinical strain C7) from eight clinical (H. parasuis) strains and determined the underlying resistance mechanism. Then, we investigated the reversal effect of MTon the resistance of this strain to CEC. Results and Discussion: The production of ß-lactamase, overexpression of AcrAB-TolC system, and formation of biofilm might not be responsible for the resistance of clinical strain C7 to CEC. Fourteen mutation sites were found in four PBP genes (ftsI, pbp1B, mrcA, and prcS) of clinical strain C7, among which the mutation sites located in ftsI (Y103D and L517R) and mrcA (A639V) genes triggered the resistance to CEC. The minimum inhibitory concentration (MIC) of CEC against clinical strain C7 was reduced by two to eight folds after MT treatment, accompanied by the significant down-regulated expression of mutated ftsI and mrcA genes. Based on such results, we believed that MT could reverse the resistance of H. parasuis to CEC by inhibiting the mutations in ftsI and mrcA genes. Our research would provide useful information for restoring the antimicrobial activity of ß-lactams and improving the therapeutic efficacy of Glässer's disease.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38565816

RESUMO

Miscanthus has good tolerance to multi-metal(loid)s and has received increasing attention in remediated studies of metal(loid)s-contaminated soil. In this study, we conducted phytoextraction techniques to investigate the synergic effects of remediation of multi-metal(loid)s-contaminated soil by Miscanthus floridulus (Lab.) and two plant growth-promoting bacteria (PGPB), TS8 and MR2, affiliated to Enterobacteriaceae. The results exhibited a decrease of arsenic (15.27-21.50%), cadmium (8.64-15.52%), plumbum (5.92-12.76%), and zinc (12.84-24.20%) except for copper contents in the soil in bacterial inoculation groups, indicating that MR2 and TS8 could enhance the remediation of metal(loid)s. Moreover, increased fresh/dry weight and height indicated that inoculated bacteria could promote Miscanthus growth. Although the activities of antioxidant enzymes and the content of chlorophyll in the overground tissues showed no significant increase or even decrease, the activities of antioxidant enzymes in the underground tissues and soil were elevated by 48.95-354.17%, available P by 19.07-23.02%, and available K by 15.34-17.79% (p < 0.05). Bacterial inoculants could also decrease the soil pH. High-throughput sequencing analysis showed that the bacterial inoculant affected the rhizosphere bacterial community and reduced community diversity, but the relative abundance of some PGPB was found to increase. Phylogenetic molecular ecological networks indicated that bacterial inoculants reduced interactions between rhizosphere bacteria and thereby led to a simpler network structure but increased the proportion of positive-correlation links and enhanced the metabiosis and symbiosis of those bacteria. Spearman's test showed that OTUs affiliated with Enterobacteriaceae and soil nutrients were critical for metal(loid) remediation and Miscanthus growth. The results of this study provide a basis for the synergic remediation of multi-metal(loid)s-contaminated soils by Miscanthus and PGPB and provide a reference for the subsequent regulation of Miscanthus remediation efficiency by the other PGPB or critical bacteria.

17.
J Stroke Cerebrovasc Dis ; : 107719, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38604351

RESUMO

BACKGROUND: Decompressive craniectomy (DC) reduces mortality without increasing the risk of very severe disability among patients with life-threatening massive cerebral infarction. However, its efficacy was demonstrated before the era of endovascular thrombectomy trials. It remains uncertain whether DC improves the prognosis of patients with malignant middle cerebral artery (MCA) infarction receiving endovascular therapy. METHODS: We pooled data from two trials (DEVT and RESCUE BT studies in China) and patients with malignant MCA infarction were included to assess outcomes and heterogeneity of DC therapy effect. Patients with herniation were dichotomized into DC and conservative groups according to their treatment strategy. The primary outcome was the rate of mortality at 90 days. Secondary outcomes included disability level at 90 days as measured by the modified Rankin Scale score (mRS) and quality-of-life score. The associations of DC with clinical outcomes were performed using multivariable logistic regression. RESULTS: Of 98 patients with herniation, 37 received DC surgery and 61 received conservative treatment. The median (interquartile range) was 70 (62-76) years and 40.8% of the patients were women. The mortality rate at 90 days was 59.5% in the DC group compared with 85.2% in the conservative group (adjusted odds ratio, 0.31 [95% confidence interval (CI), 0.10-0.94]; P=0.04). There were 21.6% of patients in the DC group and 6.6% in the conservative group who had a mRS score of 4 (moderately severe disability); and 10.8% and 4.9%, respectively, had a score of 5 (severe disability). The quality-of-life score was higher in the DC group (0.00 [0.00-0.14] vs 0.00 [0.00-0.00], P=0.004), but DC treatment was not associated with better quality-of-life score in multivariable analyses (adjusted ß Coefficient, 0.02 [95% CI, -0.08-0.11]; p=0.75). CONCLUSIONS: DC was associated with decreased mortality among patients with malignant MCA infarction who received endovascular therapy. The majority of survivors remained moderately severe disability and required improvement on quality of life. CLINICAL TRIAL REGISTRATION: The DEVT trial: http://www.chictr.org. Identifier, ChiCTR-IOR-17013568. The RESCUE BT trial: URL: http://www.chictr.org. Identifier, ChiCTR-INR-17014167.

18.
Assessment ; : 10731911241241495, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38606887

RESUMO

The interpersonal problem circumplex is extensively used in the field as an assessment framework for understanding the interpersonal implications of a range of personality and psychopathology constructs. The vast majority of this large literature has been conducted in Western convenience and clinical samples. We computed interpersonal problem structural summary parameters for a range of personality and psychopathology variables in two Chinese offender samples (N = 424 and N = 555) and one undergraduate sample (N = 511) to test how well findings from Western samples generalize to Chinese undergraduates and offenders. The results showed that findings in Western samples generalized reasonably well to Chinese young adult and forensic contexts, although the interpersonal profiles of external variables were less specific in Chinese samples. Compared with undergraduates, interpersonal distress has stronger associations with the mental health of offenders. This study further elaborates the interpersonal correlates of individual differences in personality and psychopathology across cultures and assessment contexts, and it also extends the literature examining interpersonal problems in forensic settings.

19.
Arch Oral Biol ; 163: 105965, 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38593562

RESUMO

OBJECTIVE: Porphyromonas gingivalis (P. gingivalis) is a key etiological agent in periodontitis and functions as a facultative intracellular microorganism and involves many virulence factors. These virulence factors participate in multiple intracellular processes, like ferroptosis, the mechanistic underpinnings remain to be elucidated. Aim of this study was to investigate the effects of virulence factors on the host cells. DESIGN: Human umbilical vein endothelial cells (HUVECs) were treated with 4% paraformaldehyde-fixed P. gingivalis, and subsequent alterations in gene expression were profiled via RNA-seq. Further, the molecules associated with ferroptosis were quantitatively analyzed using qRT-PCR and Western blot. RESULTS: A total of 1125 differentially expressed genes (DEGs) were identified, encompassing 225 upregulated and 900 downregulated. Ferroptosis was conspicuously represented in the kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis, with notable upregulation of Heme oxygenase 1 (HMOX1), Ferritin light chain (FTL), and Solute carrier family 3 member 2 (SLC3A2) and downregulation of Scavenger receptor class A member 5 (SCARA5) and glutaminase (GLS). Random selection of DEGs for validation through qRT-PCR corroborated the RNA-Seq data (R2 = 0.93). Kelch like ECH associated protein 1 (Keap1) protein expression decreased after 4 and 8 h, while NFE2 like bZIP transcription factor 2 (Nrf2) and HMOX1 were elevated, with significant nuclear translocation of Nrf2. CONCLUSIONS: The virulence factors of P. gingivalis may potentially instigating ferroptosis through activation of the Keap1-Nrf2-HMOX1 signaling cascade, in conjunction with modulating the expression of other ferroptosis-associated elements. Further research is necessary to achieve a thorough comprehension of these complex molecular interactions.

20.
Artigo em Inglês | MEDLINE | ID: mdl-38598155

RESUMO

Formaldehyde (HCHO) is one of the primary indoor air pollutants, and efficiently eliminating it, especially at low concentrations, remains challenging. In this study, BiVO4-TiO2 catalyst was developed using ultrasonic blending technology for the photocatalytic oxidation of low-level indoor HCHO. The crystal structure, surface morphology, element distribution, and active oxidation species of the catalyst were examined using XRD, SEM, TEM, UV-Vis, EDS, and ESR techniques. Our results demonstrated that the BiVO4-TiO2 catalyst, prepared by ultrasonic blending, exhibited good oxidation performance and stability. The HCHO concentration reduced from 1.050 to 0.030 mg/m3 within 48 h, achieving a removal rate of 97.1%. The synergy between BiVO4 and TiO2 enhanced the efficiency of separating photogenerated carriers and minimized the likelihood of recombination between photogenerated electrons and holes. Additionally, this synergy significantly enhanced the presence of hydroxyl radicals (·OH) on the catalyst, resulting in an oxidation performance superior to that of either BiVO4 or TiO2. Our research offers valuable insights for the development of new photocatalysts to address HCHO pollution.

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