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1.
Phys Chem Chem Phys ; 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35775962

RESUMO

Inhibitors that competitively bind MDM2/MDMX can block the inhibition of P53 by MDM2/MDMX and restart its tumor-suppressive effect. Molecular studies targeting MDM2/MDMX inhibitors have always been a hot topic in anticancer drug design. Although numerous inhibitors have been designed previously against MDM2/MDMX, their dual inhibition efficacy has not been demonstrated, and few studies assessed the general causes affecting the dual inhibition of MDM2/MDMX by these inhibitors. Here, molecular dynamics simulations and alanine scanning combined with the interaction entropy method were employed to precisely investigate whether 16 inhibitors could dually inhibit MDM2/MDMX and the similarities and differences in the interaction modes. Thereby addressing the key residue sites affecting dual inhibition. Residues L54/M53, I61/60, M62/61, Y67/66, and V93/92 of MDM2/MDMX, which are in corresponding positions in both protein structures, provide significant conditions for these inhibitors to bind to MDM2/MDMX tightly. In addition, most of these inhibitors prefer to bind MDM2 than MDMX, and residues H96 and I99 in MDM2 are attractive targets for inhibitors, resulting in inhibitors binding to MDM2/MDMX with different affinity. These key residues should be considered in the development of dual inhibitors. For these 16 inhibitors, most have dual inhibitory potential for MDM2/MDMX based on the binding affinity of the complexes. Still, it is questionable whether they can exert excellent dual inhibition considering the assessment of the hot-spots. At least their binding affinity for MDMX is not superior to that for MDM2 due to the difference in energy of the van der Waals interactions at the key sites. Furthermore, based on the analysis of three representative inhibitors (TUZ/HRH and HRQ with different binding preferences for MDM2/MDMX), 3-chloropyridine in TUZ leads to the differential binding affinity between the inhibitor and MDM2/MDMX. It readily forms hydrophobic interactions with the surrounding residues H96 and I99. But this phenomenon does not occur in the TUZ-MDMX system, implying the critical role of residues H96/P95 and I99/L98. And the completely different binding mechanism of HRQ binding to MDM2/MDMX explains its inability to inhibit MDM2 well. Thus, we are cautious about its dual inhibitory ability. Besides, HRH is more prone to strong van der Waals interactions with MDM2 than MDMX whereas its 2-chlorofluorobenzene is detrimental to this. We hope that these findings will provide reliable molecular insights for the screening and optimization of targeting MDM2/MDMX dual inhibitors.

2.
J Phys Chem Lett ; : 6064-6073, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35758899

RESUMO

Multiple-site mutated SARS-CoV-2 Delta and Omicron variants may trigger immune escape against existing monoclonal antibodies. Here, molecular dynamics simulations combined with the interaction entropy method reveal the escape mechanism of Delta/Omicron variants to Bamlanivimab/Etesevimab. The result shows the significantly reduced binding affinity of the Omicron variant for both antibodies, due to the introduction of positively charged residues that greatly weaken their electrostatic interactions. Meanwhile, significant structural deflection induces fewer atomic contacts and an unstable binding mode. As for the Delta variant, the reduced binding affinity for Bamlanivimab is owing to the alienation of the receptor-binding domain to the main part of this antibody, and the binding mode of the Delta variant to Etesevimab is similar to that of the wild type, suggesting that Etesevimab could still be effective against the Delta variant. We hope this work will provide timely theoretical insights into developing antibodies to prevalent and possible future variants of SARS-CoV-2.

3.
Int Immunopharmacol ; 108: 108905, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35729836

RESUMO

Studies have confirmed that the heart is the main target organ of lipopolysaccharide (LPS) attacks, and 14-3-3γ and protein kinase C epsilon (PKCε) are the endogenous protective proteins. Puerarin (Pue) is the major bioactive ingredient isolated from the root of Pueraria lobata. It possesses many pharmacological properties, which has been widely used in the treatment and adjuvant therapy of cardio- and cerebrovascular diseases and cancer, etc. The study intended to explore the effects and mechanism of Pue pretreatment to protect myocardium against LPS injury. Adult mice and primary cultured neonatal rat cardiomyocytes were pretreated with Pue, and the injury model was made with LPS. Results showed that Pue pretreatment alleviated LPS-induced injury, as demonstrated by increased cell viability, decreased LDH activity and apoptosis, inhibited excess oxidative stress and the inflammatory cytokine release, and maintained mitochondrial function. Furthermore, Pue pretreatment upregulated 14-3-3γ expression, interacted with PKCε, which was phosphorylated and impelled migration to mitochondria, and then activated adaptive autophagy and protected the myocardium. However, pAD/14-3-3γ-shRNA or 3-MA (an autophagy inhibitor) could weaken the above effects of Pue pretreatment. Together, Pue pretreatment could activate adaptive autophagy by the 14-3-3γ/PKCε pathway and protect the myocardium against LPS injury.


Assuntos
Traumatismos Cardíacos , Isoflavonas , Animais , Apoptose , Autofagia , Isoflavonas/farmacologia , Isoflavonas/uso terapêutico , Lipopolissacarídeos/farmacologia , Camundongos , Miócitos Cardíacos/metabolismo , Proteína Quinase C-épsilon/metabolismo , Proteína Quinase C-épsilon/farmacologia , Ratos , Ratos Sprague-Dawley
4.
Chem Commun (Camb) ; 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35726708

RESUMO

Long-lived charge separated (CS) triplet state (2.6 µs) and thermally activated delayed fluorescence (TADF) [τ = 282 ns (90.4%)/2.4 µs (9.6%)] were observed in an anthraquinone-phenoxazine electron donor-acceptor dyad via the electron spin control method, and emissive 1CS and non-emissive 3CS states were discriminated via nanosecond transient absorption spectroscopy and global analysis.

5.
Front Endocrinol (Lausanne) ; 13: 854875, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35574013

RESUMO

Background and Aims: Glycated hemoglobin (HbA1c) associates with the risk of arterial stiffness, and such association can be found between fasting blood glucose (FBG), postprandial blood glucose (PBG), triglyceride-glucose index (TyG index), and arterial stiffness. However, the results were inconsistent, longitudinal studies were sparse, and comparison of these glycemic parameters was less conducted. We aimed to explore the longitudinal relationship between HbA1c and arterial stiffness and compare the effect of the parameters. Methods: Data were collected from 2011 to 2019 in Beijing Health Management Cohort (BHMC) study. Cox proportional hazard models were fitted to investigate the association between the parameters and arterial stiffness. A generalized estimation equation (GEE) analysis was conducted to investigate the effect of repeated measurements of glycemic parameters. A receiver operating characteristic (ROC) analysis was performed to compare the predictive value of glycemic parameters for arterial stiffness. Results: Among 3,048 subjects, 591 were diagnosed as arterial stiffness during the follow-up. The adjusted hazard ratio (HR) [95% confidence interval (CI)] for arterial stiffness of the highest quartile group of HbA1c was 1.63 (1.22-2.18), which was higher than those of FBG, PBG, and TyG index. The nonlinear association of arterial stiffness with HbA1c and PBG was proved. The robust results of the sensitivity analysis were obtained. Conclusions: HbA1c is an important risk factor of arterial stiffness compared with PBG, FBG, and TyG index, and has a strong predictive ability for arterial stiffness among non-diabetics and the general population.


Assuntos
Rigidez Vascular , Biomarcadores , Glicemia , China/epidemiologia , Glucose , Hemoglobina A Glicada , Humanos , Estudos Longitudinais , Triglicerídeos
6.
Oxid Med Cell Longev ; 2022: 1482811, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35585879

RESUMO

Myelodysplastic syndrome (MDS) is a heterogeneous group of clonal hematopoietic stem cell disorders. Studies have shown the involvement of an abnormal immune system in MDS pathogenesis. The gut microbiota are known to influence host immunity and metabolism, thereby contributing to the development of hematopoietic diseases. In this study, we performed gut microbiome and plasma metabolomic analyses in patients with MDS and healthy controls. We found that patients with MDS had a different gut microbial composition compared to controls. The gut microbiota in MDS patients showed a continuous evolutionary relationship from the phylum to the species level. At the species level, the abundance of Haemophilus parainfluenzae, Streptococcus luteciae, Clostridium citroniae, and Gemmiger formicilis increased, while that of Prevotella copri decreased in MDS patients compared to controls. Moreover, abundance of bacterial genera correlated with the percentage of lymphocyte subsets in patients with MDS. Metabolomic analysis showed that the concentrations of hypoxanthine and pyroglutamic acid were increased, while that of 3a,7a-dihydroxy-5b-cholestan was decreased in MDS patients compared to controls. In conclusion, gut microbiome and plasma metabolomics are altered in patients with MDS, which may be involved in the immunopathogenesis of the disease.


Assuntos
Microbioma Gastrointestinal , Síndromes Mielodisplásicas , Bactérias , Fezes , Humanos , Metabolômica , Plasma
7.
Cell Host Microbe ; 2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35594867

RESUMO

The SARS-CoV-2 Omicron variant has evolved into four sub-lineages-BA.1, BA.1.1, BA.2, and BA.3-with BA.2 becoming dominant worldwide. We and others have reported antibody evasion of BA.1 and BA.2, but side-by-side comparisons of Omicron sub-lineages to vaccine-elicited or monoclonal antibody (mAb)-mediated neutralization are necessary. Using VSV-based pseudovirus, we report that sera from individuals vaccinated by two doses of an inactivated whole-virion vaccine shows weak to no neutralization activity, while homologous or heterologous boosters markedly improve neutralization titers against all Omicron sub-lineages. We also present neutralization profiles against a 20 mAb panel, including 10 authorized or approved, against the Omicron sub-lineages, along with mAb mapping against single or combinatorial spike mutations. Most mAbs lost neutralizing activity, while some demonstrate distinct neutralization patterns among Omicron sub-lineages, reflecting antigenic differences. Collectively, our results suggest the Omicron sub-lineages threaten the neutralization efficacy of current vaccines and antibody therapeutics, highlighting the importance of vaccine boosters.

8.
Nat Metab ; 4(5): 608-626, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35551509

RESUMO

Impaired glucose-stimulated insulin secretion (GSIS) is a hallmark of type-2 diabetes. However, cellular signaling machineries that control GSIS remain incompletely understood. Here, we report that ß-klotho (KLB), a single-pass transmembrane protein known as a co-receptor for fibroblast growth factor 21 (FGF21), fine tunes GSIS via modulation of glycolysis in pancreatic ß-cells independent of the actions of FGF21. ß-cell-specific deletion of Klb but not Fgf21 deletion causes defective GSIS and glucose intolerance in mice and defective GSIS in islets of type-2 diabetic mice is mitigated by adenovirus-mediated restoration of KLB. Mechanistically, KLB interacts with and stabilizes the cytokine receptor subunit GP130 by blockage of ubiquitin-dependent lysosomal degradation, thereby facilitating interleukin-6-evoked STAT3-HIF1α signaling, which in turn transactivates a cluster of glycolytic genes for adenosine triphosphate production and GSIS. The defective glycolysis and GSIS in Klb-deficient islets are rescued by adenovirus-mediated replenishment of STAT3 or HIF1α. Thus, KLB functions as a key cell-surface regulator of GSIS by coupling the GP130 receptor signaling to glucose catabolism in ß-cells and represents a promising therapeutic target for diabetes.


Assuntos
Diabetes Mellitus Experimental , Glucose , Animais , Receptor gp130 de Citocina/genética , Receptor gp130 de Citocina/metabolismo , Glucose/metabolismo , Glicólise , Secreção de Insulina , Camundongos
9.
Biochem Biophys Res Commun ; 612: 77-83, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35512460

RESUMO

In higher plants, the PSI core complex is associated with light-harvesting complex I (LHCI), forming the PSI-LHCI super-complex. In vascular plants, four major antenna proteins (LHCA1-4) are assembled in the order of LHCA1, LHCA4, LHCA2, and LHCA3 into a crescent-shaped LHCI, while LHCA5 and LHCA6 are minor antenna proteins. By contrast, in moss and green algae, LHCA5 or LHCA5-like protein functions as one of the major antenna proteins by residing at the second site of LHCI. In order to learn the effect of binding different LHCA proteins, i.e. LHCA4 or LHCA5, within the PSI-LHCI super-complex on photosynthetic properties of plants, we constructed LHCA5 overexpression plants with a wild type (WT) background and an lhca4 mutant background in Arabidopsis thaliana. The results showed that: (i) there are little difference in phenotype, pigment composition and chlorophyll fluorescence parameters between the transgenic Arabidopsis and their corresponding background materials; (ii) in spite of a small amount of LHCA5, the LHCA5-included PSI-LHCI super-complex can be obtained by extracting samples incubated with anti-FLAG M2 Affinity Gel, in which LHCA5 is found to substitute for LHCA4 as analyzed by immunoblotting analysis; (iii) the replacement of LHCA4 with LHCA5 within PSI-LHCI super-complex leads to a blue shift in low temperature fluorescence emission, suggesting a decrease in far-red absorbance. These results provide new clues for understanding the position and function of LHCA4 and LHCA5 during the evolution of green plants from aquatic to terrestrial lifestyles.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fluorescência , Complexos de Proteínas Captadores de Luz/química , Complexos de Proteínas Captadores de Luz/genética , Complexos de Proteínas Captadores de Luz/metabolismo , Complexo de Proteína do Fotossistema I/química
10.
Seizure ; 99: 153-158, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35640469

RESUMO

Purpose To investigate the variations of the thalamocortical circuit between the focal cortical dysplasia (FCD) type II patients with sleep-related epilepsy (SRE) and those without SRE (non-SRE). Methods Patients with epilepsy who had histologically proven FCD type II were enrolled. Those without diffusion tensor image and 3-dimensional (3D) T1 MRI sequences were excluded. Thalamocortical structural connectivity to lesion and non-lesion regions was quantified using probabilistic tractography. Fractional anisotropy (FA) and mean diffusivity (MD) were computed. Results A total of 30 consecutive patients were included. Among them, 18 patients (60%) had SRE. Analysis of covariance showed that smaller lesion size was significantly associated with SRE (p=0.048). Compared to patients with non-SRE, patients with SRE showed a significant decrease in FA of thalamocortical projections to the lesion region (p=0.007). No difference was observed in the thalamocortical connectivity to the non-lesion region between patients with SRE and non-SRE. Among the patients with SRE, a significant decrease in FA of thalamocortical projections to the lesion region was noted compared with the contralateral homotopic non-lesion region (p=0.026). Conclusion The data provide evidence of disparity in thalamocortical projections to the lesion regions between SRE and non-SRE. This might indicate the underlying pathophysiology or neuroanatomical substrates of SRE related to the FCD type II.


Assuntos
Epilepsia Reflexa , Malformações do Desenvolvimento Cortical do Grupo I , Malformações do Desenvolvimento Cortical , Epilepsia , Humanos , Imageamento por Ressonância Magnética/métodos , Malformações do Desenvolvimento Cortical/complicações , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Malformações do Desenvolvimento Cortical/patologia , Malformações do Desenvolvimento Cortical do Grupo I/complicações , Malformações do Desenvolvimento Cortical do Grupo I/diagnóstico por imagem , Sono
11.
Nanomaterials (Basel) ; 12(8)2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35457980

RESUMO

In this paper, we established a progressive multiscale model for a plain-woven composite with hollow microfibers and beads and investigated the general conductive thermal response. Micromechanic techniques were employed to predict the effective conductivity coefficients of the extracted representative volume elements (RVEs) at different scales, which were then transferred to higher scales for progressive homogenization. A structural RVE was finally established to study the influence of microscale parameters, such as phase volume fraction, the thickness of the fibers/beads, etc., on the effective and localized behavior of the composite system It was concluded that the volume fraction of the hollow glass beads (HGBs) and the thickness of the hollow fibers (HFs) had a significant effect on the effective thermal coefficients of the plain-woven composites. Furthermore, it was found that an increasing HGB volume fraction had a more significant effect in reducing the thermal conductivity of composite. The present simulations provide guidance to future experimental testing.

12.
J Neuroimmunol ; 367: 577876, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35489221

RESUMO

Oligodendrocyte (OL) death and remyelination failure lead to progressive neurological deficits in multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE). Matrine (MAT), a quinolizidine alkaloid component derived from the root of Sophora flavescens, has the capacity to effectively inhibit central nervous system (CNS) inflammation and to promote neuroregeneration. In the present study we explored its regulatory mechanism on the Wnt/ß-catenin/TCF7L2 pathway, a negative modulator for myelination, in MOG35--55 peptide-induced EAE. Our results clearly indicate that MAT treatment reduced the activation of Wnt3a and ß-catenin in the CNS of EAE mice, accompanied by the activation of GSK3ß and decreased expression of cyclin D1 and Axin2, two target genes of the Wnt3a/ß-catenin pathway. In addition, MAT increased OL maturation and myelination, as evidenced by the decreased number of NG2+Olig2+ cells and the increased numbers of MBP+ and CC1+Olig2+ cells. Taken together, these findings indicate that MAT treatment promoted the maturation of OLs and myelin repair, which is closely related to the modulation of the Wnt/ß-catenin/TCF7L2 signaling pathway.


Assuntos
Alcaloides , Encefalomielite Autoimune Experimental , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Animais , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/metabolismo , Camundongos , Quinolizinas , Transdução de Sinais , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/farmacologia , beta Catenina/metabolismo , beta Catenina/farmacologia
13.
Front Genet ; 13: 833132, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401685

RESUMO

Bone health is particularly important for high-yielding commercial layer chickens. The keel of poultry is an extension of the abdomen side of the sternum along the sagittal plane and is one of the most important bones. In this study, the keel phenotype of White Leghorns laying hen flocks showed significant individual differences. To clarify its genetic mechanism, we first estimated the heritability of keel bend (KB) in White Leghorn, recorded the production performance of the chicken flock, examined the blood biochemical indexes and bone quality in KB and keel normal (KN) chickens, and performed whole-genome pooled sequencing in KB and KN chickens. We then performed selection elimination analysis to determine the genomic regions that may affect the keel phenotypes. The results show that KB is a medium heritability trait. We found that cage height had a significant effect on the KB (p < 0.01). At 48 weeks, there were significant differences in the number of eggs, the number of normal eggs, and eggshell strength (p < 0.05). The content of parathyroid hormone was lower (p < 0.01) and that of calcitonin was higher (p < 0.01) in KB chickens than in KN chickens. The differences in bone mineral density, bone strength, and bone cortical thickness of the humerus and femur were extremely significant (p < 0.01), with all being lower in KB chickens than in KN chickens. In addition, the bones of KB chickens contained more fat organization. A total of 128 genes were identified in selective sweep regions. We identified 10 important candidate genes: ACP5, WNT1, NFIX, CNN1, CALR, FKBP11, TRAPPC5, MAP2K7, RELA, and ENSGALG00000047166. Among the significantly enriched Kyoto Encyclopedia of Genes and Genomes pathways found, we identifed two bone-related pathways, one involving "osteoclast differentiation" and the other the "MAPK signaling pathway." These results may help us better understand the molecular mechanism of bone traits in chickens and other birds and provide new insights for the genetic breeding of chickens.

14.
J Chin Polit Sci ; : 1, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35431530

RESUMO

[This retracts the article DOI: 10.1007/s11366-020-09692-6.].

15.
Front Microbiol ; 13: 843650, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432246

RESUMO

The beneficial effects of the probiotic strain Lactiplantibacillus plantarum (formerly Lactobacillus plantarum) are based on its adherence and colonization ability in the gut. However, little is known about the migration and long-term gut colonization of the strain. This study evaluated the gut colonization modes of Lactiplantibacillus plantarum RS-09 to identify the strain with long-term gut colonization potential. We established CFDA/SE-labeled RS-09 to study the temporal and spatial distribution of RS-09 in the intestine as well as to analyze its persistence in different parts of the intestine by flow cytometry. This study has shown that the RS-09 strain maintains strong adhesion abilities under acid (pH 2.5) and base (pH 8.5) conditions. In addition, CFDA/SE can be used as an indicator for the labeling of L. plantarum RS-09 in the intestinal tract in vivo. We established a growth kinetics model of RS-09 to elucidate its persistence in the intestine. In vivo persistence experiments showed that the persistence rate of RS-09 was the highest in the cecum (69.5%) and the lowest in the duodenum (12.8%) at 96 h. After 20 days, RS-09 was predominantly localized in the cecum and colon steadily. These studies provide new insights into the long-term persistence of L. plantarum in the gastrointestinal tract. The CFDA/SE label system may be used to study the in vivo colonization dynamics of other probiotic strains.

16.
Materials (Basel) ; 15(7)2022 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-35407966

RESUMO

Highly flexible silver nanowire-based transparent conductive films (AgNWs TCFs) were large-scale fabricated by slot-die coating AgNWs inks on a flexible polyethylene terephthalate (PET) substrate, and further fabricated into a transparent film heater. Appropriate flow rate, coating speed, and AgNWs concentration allow the construction of the 15 cm × 15 cm AgNW TCFs with a sheet resistance (Rs) of less than 20 Ω/sq, a transmittance (T) at 550 nm higher than 95%, and a haze less than 3.5%. The resultant AgNW TCFs heater possesses high uniformity and superior mechanical stability and can reach a Joule heating temperature of 104 °C with a voltage of 12 V. The slot-die coating method has great potential for large-scale production of AgNW based film heaters promisingly used in window defrost and deicer systems.

17.
Phys Chem Chem Phys ; 24(15): 8683-8694, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35364605

RESUMO

The SARS-CoV-2 Delta (B.1.617.2) variant was identified in India in October 2020, and it has quickly become the mainstream strain with strong toxicity and spread, posing great challenges to epidemic control. However, the molecular mechanism of its powerful infectivity remains unclear. It is meaningful to investigate the process of Delta variant's receptor-binding domain (RBD) binding to angiotensin-converting enzyme 2 (ACE2). Here, we performed three repeated molecular dynamics simulations for each system to avoid accidents, and the alanine scanning combined with the interaction entropy (ASIE) method was utilized to evaluate the binding free energy. Through the detailed energy and conformational analysis, the binding mechanism of the Delta variant was illustrated. The results showed that the existence of L452R and T478K mutations can trigger the effective hijacking of ACE2 by the Delta variant through the following three ways: (i) these two mutations can significantly enhance the electrostatic energy of the system by the introduction of two positively charged amino acids (Arg and Lys), thereby increasing the binding affinity of RBD and ACE2, (ii) the Loops 1, 3, and 4 in the receptor-binding motif (RBM) of RBD form a tighter conformation under the dominance of the T478K mutation, allowing ACE2 to be captured more effectively than the wild-type system, and (iii) these conformational changes lead to a more stable hydrogen bond in the Delta variant, which further ensures the stability of the binding. In addition, to explore the effect of mutations on the antibody, the key residues contributing to the changes in the binding ability of RBD in the Delta variant with the existing 42 neutralizing monoclonal antibodies (mAbs) have been preliminarily evaluated. The present study reveals the molecular mechanism for the increased infectivity of SARS-CoV-2 caused by mutations, and the key sites that cause antigenic changes were screened. It provides important theoretical insights for the development of novel targeted RBD drugs and antibodies.


Assuntos
COVID-19 , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2 , Humanos , Mutação , Ligação Proteica , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
18.
Free Radic Res ; 56(2): 173-184, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35382666

RESUMO

Anoxia/reoxygenation (A/R) injury causes dysfunction of rat renal tubular epithelial cells (NRK-52E), which is associated with excess reactive oxygen species (ROS) generation and eventually leads to apoptosis. Ferulic acid (FA), a phenolic acid, which is abundant in fruits and vegetables. FA possesses the properties of scavenging free radicals and cytoprotection against oxygen stress. In the study, the protective effects of FA against NRK-52E cells damage induced by A/R were explored and confirmed the role of AMP-activated protein kinaseα1 (AMPKα1). We found that after NRK-52E cells suffered A/R damage, FA pretreatment increased the cell viability and decreased LDH activity in culture medium in a concentration-dependent manner, the activities of endogenous antioxidant enzymes such as glutathione peroxidase, superoxide dismutase and catalase improved, intracellular ROS generation and malondialdehyde contents mitigated. In addition, pretreatment of 75 µM FA ameliorated mitochondrial dysfunction by A/R-injury and ultimately decreased apoptosis (25.3 ± 0.61 vs 12.1 ± 0.60), which was evidenced by preventing the release of cytochrome c from mitochondria to the cytoplasm. 75 µM FA pretreatment also significantly upregulated AMPKα1 expression (3.16 ± 0.18 folds) and phosphorylation (2.56 ± 0.13 folds). However, compound C, a specific AMPK inhibitor, significantly attenuated FA pretreatment's effects, as mentionedabove. These results firstly clarified that FA pretreatment attenuated NRK-52E cell damage induced by A/R via upregulating AMPKα1 expression and phosphorylation.


Assuntos
Apoptose , Estresse Oxidativo , Animais , Ácidos Cumáricos , Células Epiteliais/metabolismo , Hipóxia/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo
19.
Sci Rep ; 12(1): 5987, 2022 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-35397667

RESUMO

The presence of dyes and heavy metals in water sources as pollutants is harmful to human and animal health. Therefore, this study aimed to evaluate the efficacy of zinc ferrite (ZnFe2O4) nanoparticles (ZF-NPs) due to their outstanding properties including cost-effectiveness, availability, and applicability for removal of auramine O (AO), methylene blue (MB), and Cd (II). The effect of the main operating parameters such as AO concentration, MB concentration, Cd (II) concentration, adsorbent amount, solution pH, and sonication time was optimized by the response surface methodology (RSM). Optimal conditions were obtained at adsorbent amount of 0.25 g, pH = 6, sonication time of 15 min, and concentration of 15 mg L-1, and more than 91.56% were removed from all three analytes. The adsorption of AO, MB, and Cd (II) onto ZF-NPs followed pseudo-second-order kinetics and the equilibrium data fitted well with Langmuir isotherm. The maximum adsorption capacities of ZF-NPs for AO, MB and Cd (II) were as high as 201.29 mg g-1, 256.76 mg g-1 and 152.48 mg g-1, respectively. Also, the reuse of the adsorbent was investigated, and it was found that the adsorbent can be used for up to five cycles. Based on the results of interference studies, it was found that different ions do not have a significant effect on the removal of AO, MB, and Cd (II) in optimal conditions. The ZF-NPs was investigated successfully to remove AO, MB, and Cd (II) from environmental water samples. The results of this study showed that ZF-NPs can be used as a suitable adsorbent to remove AO, MB, and Cd (II) from aqueous solution.


Assuntos
Metais Pesados , Nanopartículas , Poluentes Químicos da Água , Adsorção , Benzofenoneídio , Cádmio/análise , Corantes/química , Concentração de Íons de Hidrogênio , Íons , Cinética , Azul de Metileno/química , Nanopartículas/química , Água/química , Poluentes Químicos da Água/análise
20.
Int J Urol ; 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35474347

RESUMO

OBJECTIVES: To investigate perioperative clinicopathological predictors and establish a predictive nomogram for survival in patients with renal cell carcinoma and venous tumor thrombus undergoing nephrectomy and thrombectomy. METHODS: Patients with renal cell carcinoma and venous tumor thrombus undergoing nephrectomy and thrombectomy were included in the study between January 2014 and June 2020. Cox regression analysis was used for univariate and multivariate survival analyses. A predictive nomogram for survival was established and internally validated using bootstrap resampling method. RESULTS: A total of 228 patients were enrolled in this study. The median age was 60 years (interquartile range 53-66 years), consisting of 174 (76.3%) males and 54 (23.7%) females. The median follow-up time was 17.5 months (range 1-74 months), 26.8% (61 of 228) patients died of all causes. In multivariable analysis, hemoglobin less than the lower limit of normal (hazard ratio 1.73; 95% confidence interval 1.01-2.96; P = 0.045), sarcomatoid feature (hazard ratio 3.67; 95% confidence interval 1.97-6.82; P < 0.001), perirenal fat invasion (hazard ratio 1.80; 95% confidence interval 1.05-3.09; P = 0.033), histological subtype (hazard ratio 2.74; 95% confidence interval 1.39-5.41; P = 0.004), and metastasis at surgery (hazard ratio 1.71; 95% confidence interval 1.01-2.90; P = 0.047) were independently associated with overall survival. The result of internal validation presented that the predictive performance of the nomogram for survival measured by C-index was 0.77. CONCLUSIONS: We developed a predictive nomogram with well-internal validation for survival in patients with renal cell carcinoma and venous tumor thrombus, which can greatly promote risk stratification and treatment planning.

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