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1.
Materials (Basel) ; 15(11)2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35683158

RESUMO

Nickel-based alloys, referred to as the most difficult-to-cut materials, pose a great challenge to cutting tool materials due to their excellent high-temperature properties. Ceramic tools have the potential to improve the machinability of these alloys with the advance of toughening mechanisms. In this work, the wear mechanisms of SiC whisker-reinforced alumina and Sialon when high-speed turning Inconel 718 alloy under dry cutting condition were investigated. The results showed that the wear process of Al2O3-SiCw WG300 was dominated by the notch wear, while the flank wear characterized by ridges and grooves perpendicular to the cutting edge was the main wear mode for Sialon SX9. A Ti-enriched belt was found at the boundary of the wear band for both ceramic tools. The SEM inspection and EDS analysis for this belt suggested the trace of diffusion between the workpiece material and tool matrix. As for the notch formation, the periodically adhesive action of the workpiece material at the depth-of-cut line combined with the thermal shock resistance of ceramic tools were considered to account for its formation. In addition, the oxidation of the workpiece material at the depth-of-cut line played a positive role in reducing the adhesive affinity and consequent notch wear.

2.
ACS Omega ; 7(22): 18761-18769, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35694490

RESUMO

The most essential issue facing the world today is the provision of energy and sustainable consumption of natural resources. Pretreatment is an essential step to produce biofuels from lignocellulosic biomass. In this study, ammonia fiber explosion (AFEX) combined with NaOH (A-NaOH) pretreatment effects on the characteristics of Pennisetum sinese (herbaceous), oak (hardwood), and camphor wood (softwood) were assessed using enzymatic efficiency analysis, thereby identifying the composition properties of subsequent bio-H2 production. The results show that the lignin removal (84.2%, 59.7%, and 36.7%, respectively) at 5%A-NaOH conditions and enzymatic efficiency (36.2%, 9.7%, and 6.5%, respectively) of Pennisetum sinese (P. sinese), oak, and camphor wood were significantly increased under 4% A-NaOH conditions. Further A-NaOH pretreatment significantly promoted dark fermentation bio-H2 production (152.3, 99.1, and 76.9 mL/g TS, respectively) and volatile acid production (4660.2, 3720.2, and 3496.2 mg/L, respectively) of P. sinese, oak, and camphor wood. These findings show that A-NaOH pretreatment is an effective means of utilization of lignocellulose resources.

3.
Front Cardiovasc Med ; 9: 879812, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35694666

RESUMO

Background: In updated international guidelines, combined albumin resuscitation is recommended for septic shock patients who receive large volumes of crystalloids, but minimal data exist on albumin use and the optimal timing in those with cardiogenic shock (CS). The objective of this study was to evaluate the relationship between resuscitation with a combination of albumin within 24 h and 30-day mortality in CS patients. Methods: We screened patients with CS from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. Multivariable Cox proportional hazards models and propensity score matching (PSM) were employed to explore associations between combined albumin resuscitation within 24 h and 30-day mortality in CS. Models adjusted for CS considered potential confounders. E-value analysis suggested for unmeasured confounding. Results: We categorized 1,332 and 254 patients into crystalloid-only and early albumin combination groups, respectively. Patients who received the albumin combination had decreased 30-day and 60-day mortality (21.7 vs. 32.4% and 25.2 vs. 34.2%, respectively, P < 0.001), and the results were robust after PSM (21.3 vs. 44.7% and 24.9 vs. 47.0%, respectively, P < 0.001) and following E-value. Stratified analysis showed that only ≥ 60 years old patients benefited from administration early albumin. In the early albumin combination group, the hazard ratios (HRs) of different adjusted covariates remained significant (HRs of 0.45-0.64, P < 0.05). Subgroup analysis showed that resuscitation with combination albumin was significantly associated with reduced 30-day mortality in patients with maximum sequential organ failure assessment score≥10, with acute myocardial infarction, without an Impella or intra-aortic balloon pump, and with or without furosemide and mechanical ventilation (HRs of 0.49, 0.58, 0.65, 0.40, 0.65 and 0.48, respectively; P < 0.001). Conclusion: This study found, compared with those given crystalloid-only, resuscitation with combination albumin within 24 h is associated with lower 30-day mortality of CS patients aged≥60. The results should be conducted to further assess in randomized controlled trials.

4.
Fitoterapia ; : 105232, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35690187

RESUMO

To find more effective anticancer agents, a series of novel dehydroabietylamine (DA) derivatives were synthesized, focusing on C-ring nitro modifications and C-18 imide introduction. Their cytotoxic activities against human tumor cell line HeLa (cervix), MCF-7 (breast), A549 (lung), HepG2 (liver), and nonmalignant cell line HUVEC (umbilical vein) in vitro were screened. The C-18 imide heterocyclic compounds 1, 2, and C-ring 14-nitro substituted 14 exhibited moderate to good cytotoxic activities and significant selectivity towards malignant cell lines. More importantly, they were significantly less cytotoxic to nonmalignant cells (HUVEC) than the parent compound and positive control doxorubicin hydrochloride (DOX). Meantime the mechanism of cytotoxicity of DA derivatives was studied. Annexin V-FITC/PI double-staining analysis suggested that cytotoxicity of compounds 2 and 14 was associated with early apoptosis induction. The interaction between compounds and DNA (herring sperm DNA) was studied using absorption spectral analysis and ethidium bromide (EB) fluorescence displacement experiments, the results exhibited that the binding of the compound to DNA was in the intercalative mode. The structure-activity relationship discussion implied that introduction of the nitro-group, especially the 14-nitro group, can significantly improve the cytotoxicity of dehydroabietylimide compounds. The relatively high cytotoxicity and significant high selectivity of compounds 2 and 14 indicated that they were particularly noteworthy. NO released amounts indicated that the amounts of NO released by the compounds bearing nitro-group were quite well associated positive correlation with their cytotoxic activity, which provide a new strategy for structure design of DA anticancer agents in the future.

5.
Front Genet ; 13: 887491, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651930

RESUMO

Residue distance prediction from the sequence is critical for many biological applications such as protein structure reconstruction, protein-protein interaction prediction, and protein design. However, prediction of fine-grained distances between residues with long sequence separations still remains challenging. In this study, we propose DuetDis, a method based on duet feature sets and deep residual network with squeeze-and-excitation (SE), for protein inter-residue distance prediction. DuetDis embraces the ability to learn and fuse features directly or indirectly extracted from the whole-genome/metagenomic databases and, therefore, minimize the information loss through ensembling models trained on different feature sets. We evaluate DuetDis and 11 widely used peer methods on a large-scale test set (610 proteins chains). The experimental results suggest that 1) prediction results from different feature sets show obvious differences; 2) ensembling different feature sets can improve the prediction performance; 3) high-quality multiple sequence alignment (MSA) used for both training and testing can greatly improve the prediction performance; and 4) DuetDis is more accurate than peer methods for the overall prediction, more reliable in terms of model prediction score, and more robust against shallow multiple sequence alignment (MSA).

6.
BMC Gastroenterol ; 22(1): 280, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35658837

RESUMO

BACKGROUND: To develop a scoring system related to the lactate clearance (ΔLA) to predict the mortality risk (MELD-ΔLA) for critically ill cirrhotic patients. METHODS: In this retrospective cohort study, 881 critically ill cirrhotic patients from the Medical Information Mart for Intensive Care (MIMIC-III) database were included eventually. The outcomes of our study were defined as ICU death, 28-day, 90-day and 1-year mortality. Predictors were identified by multivariate Cox analysis to develop the predictive scoring system. The C-index and area under the curve (AUC) of receiver operator characteristic curve (ROC) were used to identify the predicting performance of the MELD-ΔLA, sequential organ failure assessment (SOFA), chronic liver failure-sequential organ failure assessment (CLIF-SOFA), the model for end-stage liver disease (MELD), Child-Pugh, chronic liver failure consortium acute-on-chronic liver failure (CLIF-C ACLF), chronic liver failure consortium-acute decompensation (CLIF-C AD) and MELD-Na scoring systems. Additionally, subgroup analysis was also performed based on whether critically ill cirrhotic patients underwent liver transplantation. RESULTS: Creatinine, bilirubin, international normalized ratio (INR), lactate first, ΔLA and vasopressors were closely associated with ICU death of liver critically ill cirrhotic patients. The C-index of the MELD-ΔLA in ICU death was 0.768 (95% CI 0.736-0.799) and the AUC for the MELD-ΔLA scoring system in predicting 28-day, 90-day, and 1-year mortality were 0.774 (95% CI 0.743-0.804), 0.765 (95% CI 0.735-0.796), and 0.757 (95% CI 0.726-0.788), suggested that MELD-ΔLA scoring system has a good predictive value than SOFA, CLIF-SOFA, MELD, Child-Pugh, CLIF-C ACLF, CLIF-C AD) and MELD-Na scoring systems. Additionally, the study also confirmed the good predictive value of MELD-ΔLA scoring system for critically ill cirrhotic patients regardless of undergoing liver transplantation. CONCLUSION: The developed MELD-ΔLA score is a simple scoring system in predicting the risk of ICU death, 28-day, 90-day and 1-year mortality for critically ill cirrhotic patients, which may have a good predictive performance.


Assuntos
Estado Terminal , Doença Hepática Terminal , Doença Hepática Terminal/complicações , Humanos , Ácido Láctico , Cirrose Hepática/complicações , Prognóstico , Curva ROC , Estudos Retrospectivos , Índice de Gravidade de Doença
7.
Fluids Barriers CNS ; 19(1): 40, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35658877

RESUMO

BACKGROUND: Mammalian Claudin-5 is the main endothelial tight junction component maintaining blood-brain barrier (BBB) permeability, while Claudin-1 and -3 seal the paracellular space of choroid plexus (CP) epithelial cells contributing to the blood-cerebrospinal fluid barrier (BCSFB). In zebrafish, two paralogs of claudin-5a and -5b are expressed while their roles in the formation of BBB and BCSFB are unclear. METHODS: The expression patterns of Claudin-5a and -5b in zebrafish brains were systematically analyzed by immunofluorescence (IF) assay. The developmental functions of Claudin-5a and -5b were characterized by generating of claudin-5a and -5b mutants respectively. Meanwhile, the cerebral inflammation and cell apoptosis in claudin-5a-/- were assessed by live imaging of transgenic zebrafish, RT-qPCR, IF, and TUNEL assay. The integrity of BBB and BCSFB was evaluated by in vivo angiographic and dye permeation assay. Finally, RT-qPCR, whole-mount RNA in situ hybridization (WISH), and transmission electron microscopy (TEM) analyses were performed to investigate the development of cerebral vessels and choroid plexus. RESULTS: We showed that Claudin-5a and -5b are both expressed in zebrafish cerebrovascular endothelial cells (ECs). In addition, Claudin-5a was strongly expressed in CP epithelial cells. Loss of Claudin-5b showed no effect on zebrafish vasculogenesis or BBB function. In contrast, the knockout of claudin-5a caused a lethal phenotype of severe whole-brain oedema, ventricular dilatation, and cerebral hernia in zebrafish larvae, although the cerebral vasculogenesis and the development of CP were not altered. In claudin-5a-/- , although ultrastructural analysis of CP and cerebral capillary showed intact integrity of epithelial and endothelial tight junctions, permeability assay indicated a disruption of both BBB and BCSFB functions. On the molecular level, it was found that ZO-1 was upregulated in the CP epithelium of claudin-5a-/-, while the notch and shh pathway responsible for CP development was not affected due to loss of Claudin-5a. CONCLUSIONS: Our findings verified a non-functional role of zebrafish Claudin-5b in the BBB and identified Claudin-5a as the ortholog of mammalian Claudin-5, contributing to the development and the functional maintenance of both BBB and BCSFB.


Assuntos
Barreira Hematoencefálica , Peixe-Zebra , Animais , Barreira Hematoencefálica/metabolismo , Claudina-5/metabolismo , Células Endoteliais/metabolismo , Mamíferos/metabolismo , Junções Íntimas/metabolismo
8.
Biosens Bioelectron ; 213: 114442, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35679649

RESUMO

Identification and detection of extreme rare circulating tumor cells (CTCs) in peripheral blood can precisely monitor cancer recurrence and metastasis, however, how to ultra-sensitively and reliably detect CTCs is a big challenge. In this work, a ratiometric surface-enhanced Raman spectroscopy (SERS)-based strategy for ultra-sensitively and nondestructively detecting CTCs was proposed via CTCs-triggered DNA walker-assisted assembly of plasmonic nanostructure networks consisting of Walker probes and SERS tags. The Walker probes were prepared by modifying Fe3O4@SiO2@Au nanoparticles (GMNPs) with ROX-labeled EpCAM aptamer-blocked Zn2+-specific DNAzyme and hairpin-structured single-stranded DNAs H1, and the SERS tags were constructed by co-labelling hairpin-structured single-stranded DNAs H2 and Raman molecules (DTNB) on Au NPs. The aptamers can recognize EpCAM-positive CTCs via the specific binding to EpCAM, so that the activity of DNAzymes is activated with the assistance of Zn2+ to launch the DNA walker to move around for the cleavage of H1 on GMNPs. The residual fragments of H1 on GMNPs can hybridize with H2 on SERS tags and result in the formation of Walker probe-SERS tag network nanostructures (Nw NSs) with rich SERS hot spots. The reliable SERS detection of CTCs is achieved by the stable ratiometric SERS signals of DTNB and ROX generated from the Nw NSs, and a good linear relation between ratiometric SERS signal and MCF-7 cells concentration was obtained with the detection limit low to 1 cell/mL. The recovery rate of MCF-7 cells in peripheral blood is in the range of 94.0%-104.5%, which indicates a good application prospect of the novel ratiometric SERS cytosensor in the clinic detection of EpCAM-positive CTCs.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 280: 121448, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35717927

RESUMO

Inhibiting the activity of α-amylase has been considered as one efficient way to prevent and treat type 2 diabetes recently. Dalbergia odorifera, a kind of Leguminosae plant, has a positive therapeutic effect on type 2 diabetes, possibly contributing by some constituents that can inhibit the activity of α-amylase. In this study, we found that eriodictyol was one potential constituent through virtual screening. The interaction mode between eriodictyol and α-amylase was elucidated by molecular docking, multi-spectroscopic analysis, and molecular dynamic simulation. The results revealed that eriodictyol quenched the intrinsic fluorescence of α-amylase, and the quenching mode was static quenching. Eriodictyol could spontaneously interact with α-amylase, mostly stabilized and influenced by the hydrophobic interaction, while the binding sites (n) was 1.13 ± 0.07 and binding constant (Kb) was (1.43 ± 0.14) × 105 at 310 K, respectively. In addition, FT-IR and CD had been applied to identify that eriodictyol can trigger the conformational change of α-amylase. Taken together, the results provided some experimental data for developing new α-amylase inhibitors from Dalbergia odorifera, which may further prevent and treat diabetes and diabetes complications.

10.
Anal Chem ; 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35728270

RESUMO

Development of theranostic nanosystems integrating cascaded surface-enhanced Raman scattering (SERS) imaging and gene silencing therapy for accurate cancer diagnosis and treatment is still a big challenge and rarely reported. Herein, a novel Au nanoparticles (AuNPs)-based theranostic nanosystem containing AuNP-Ys and AuNP-Ds for highly sensitive and specific cancer diagnosis and treatment was proposed for cascaded SERS imaging of intracellular cancer-related miR-106a and miR-106a-triggered DNAzyme-based dual gene-silencing therapy of cancer cells. The AuNP-Ys were prepared by modifying the AuNPs with specially designed Y-motifs, and the AuNP-Ds were obtained by colabeling Raman molecules and dsDNA linkers on AuNPs. When identifying the intracellular cancer-related miRNAs, the Y-motifs and dsDNA linkers undergoes miRNA-triggered ATP-driven conformational transitions and releases the miRNA for recycling, which results in the formation of AuNP network nanostructures to generate significantly enhanced SERS signals for sensitive identification of the cancer cells as well as the amplification and specific activation of DNAzymes to catalyze the Mg2+-assisted cleavage of the Survivin and c-Jun mRNAs for effective dual gene-silencing therapy of cancer cells. The AuNP-based theranostic nanosystem achieves the synergism of target-triggered SERS imaging and DNAzyme-based dual gene-silencing therapy with enhanced specificity, sensitivity, and curative effect, which can be a powerful tool for accurate diagnosis and efficient treatment of cancers.

11.
Int J Endocrinol ; 2022: 9218113, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35726320

RESUMO

Background: Impaired glucose metabolism and insulin sensitivity have been linked to the pathogenesis of gestational diabetes mellitus (GDM). Exosomes secreted by the umbilical cord mesenchymal stromal cells (UMSCs) and circular RNAs (circRNAs) derived from exosomes have been shown to be associated with the progression of GDM-related complications. Methods: UMSCs were isolated from umbilical cords and identified through flow cytometry. Exosomes were isolated from UMSCs and were then characterized. The expression levels of RNA of hsa_circ_0046060, mmu_circ_0002819, and miR-338-3p were determined by quantitative real-time polymerase chain reaction (RT-qPCR). The intracellular glucose intake and glycogen content were measured using a High Sensitivity Glucose Assay Kit and Glycogen Assay Kit, respectively. Bioinformatics analysis and luciferase reporter assay were used to validate interactions among hsa_circ_0046060, miR-338-3p, and G6PC2. The expression of insulin receptor substrate-1 (IRS-1) and its phosphorylated form, (p-IRS-1), as well as G6PC2, was determined through western blotting. Results: UMSCs and exosomes were successfully isolated and identified. The upregulation of hsa_circ_0046060 decreased the intracellular glucose content in L-02 cells (43.45 vs. 16.87 pM/mg, P=0.0002), whereas shRNA-mediated downregulation reversed this effect (16.87 vs. 33.16 pM/mg, P=0.0011). Mmu_circ_0002819 in mice aggravated dysregulated glucose metabolism (49.88 vs. 21.69 pM/mg, P=0.0031) and insulin sensitivity (0.20 vs. 0.11 mg/mL, P=0.03) in GDM mice, which was abrogated by the knockdown of mmu_circ_0002819. The results of luciferase reporter assay revealed that miR-338-3p and G6PC2 were the potential targets of has_circ_0046060. Western blotting results showed that the reduced activation of IRS-1 induced by GDM (1.25 vs. 0.54, P=0.0001) could be rescued by the administration of si-circ-G-UMSC-EXOs (0.54 vs. 1.17, P=0.0001). Conclusion: Taken together, the inhibition of hsa_circ_0046060 expression in exosomes from GDM-derived UMSCs can alleviate GDM by reversing abnormal glucose metabolism and insulin resistance in vivo and in vitro.

12.
BMC Oral Health ; 22(1): 239, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715856

RESUMO

BACKGROUND: This study was to evaluate the predictors of xerostomia and Grade 3 xerostomia in locoregionally advanced nasopharyngeal carcinoma (NPC) patients receiving radical radiotherapy and establish prediction models for xerostomia and Grade 3 xerostomia based on the predictors. METHODS: Totally, 365 patients with locoregionally advanced NPC who underwent radical radiotherapy were randomly divided into the training set (n = 255) and the testing set (n = 110) at a ratio of 7:3. All variables were included in the least absolute shrinkage and selection operator regression to screen out the potential predictors for xerostomia as well as the Grade 3 xerostomia in locoregionally advanced NPC patients receiving radical radiotherapy. The random forest (RF), a decision tree classifier (DTC), and extreme-gradient boosting (XGB) models were constructed. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), area under the curve (AUC) and accuracy were analyzed to evaluate the predictive performance of the models. RESULTS: In the RF model for predicting xerostomia, the sensitivity was 1.000 (95%CI 1.000-1.000), the PPV was 0.990 (95%CI 0.975-1.000), the NPV was 1.000 (95%CI 1.000-1.000), the AUC was 0.999 (95%CI 0.997-1.000) and the accuracy was 0.992 (95%CI 0.981-1.000) in the training set. The sensitivity was 0.933 (95%CI 0.880-0.985), the PPV was 0.933 (95%CI 0.880-0.985), and the AUC was 0.915 (95%CI 0.860-0.970) in the testing set. Hypertension, age, total radiotherapy dose, dose at 50% of the left parotid volume, mean dose to right parotid gland, mean dose to oral cavity, and course of induction chemotherapy were important variables associated with the risk of xerostomia in locoregionally advanced NPC patients receiving radical radiotherapy. The AUC of DTC model for predicting xerostomia was 0.769 (95%CI 0.666-0.872) in the testing set. The AUC of the XGB model for predicting xerostomia was 0.834 (0.753-0.916) in the testing set. The RF model showed the good predictive ability with the AUC of 0.986 (95%CI 0.972-1.000) in the training set, and 0.766 (95%CI 0.626-0.905) in the testing set for identifying patients who at high risk of Grade 3 xerostomia in those with high risk of xerostomia. CONCLUSIONS: An RF model for predicting xerostomia in locoregionally advanced NPC patients receiving radical radiotherapy and an RF model for predicting Grade 3 xerostomia in those with high risk of xerostomia showed good predictive ability.


Assuntos
Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Xerostomia , Humanos , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Glândula Parótida/patologia , Valor Preditivo dos Testes , Radioterapia de Intensidade Modulada/efeitos adversos , Xerostomia/diagnóstico , Xerostomia/etiologia
13.
Life Sci ; 304: 120698, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35690105

RESUMO

Epidemiological studies have shown that hepatocellular carcinoma (HCC) is a main cause of tumor death worldwide. Accumulating data indicate that ginsenoside CK is an effective compound for preventing HCC growth and development. However, improvement of pharmaceutical effect of the ginsenoside CK is still needed. In our study, we performed acetylation of ginsenoside CK (CK-3) and investigated the antitumor effects of the derivative in vitro and in vivo. The cytotoxicity analysis revealed that compared with CK, CK-3 could inhibit the proliferation of multiple tumor cell lines at a lower concentration. Treating with CK-3 on HCC cells arrested cell cycle in G2/M phase and induced cell apoptosis through AO/EB staining, TUNEL analysis and flow cytometry. Meanwhile, CK-3 significantly inhibited tumor growth in an HCC xenograft model and showed no side effect on the function of the main organs. Mechanistically, whole transcriptome analysis revealed that the antitumor effect of CK-3 was involved in the Hippo signaling pathway. The immunoblotting and immunofluorescence results illustrated that CK-3 directly facilitated the phosphorylation of YAP1 and decreased the expression of the main transcription factor TEAD2 in HCC cell lines and tumor tissue sections. Collectively, our results demostrate the formation of a new derivative of ginsenoside CK and its regulatory mechanism in HCC, which could activate the Hippo-YAP1-TEAD2 signaling pathway to regulate HCC progression. This research could provide a new direction for traditional Chinese medicine in the therapy of tumors.

14.
Elife ; 112022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35703493

RESUMO

Dynein harnesses ATP hydrolysis to move cargo on microtubules in multiple biological contexts. Dynein meets a unique challenge in meiosis by moving chromosomes tethered to the nuclear envelope to facilitate homolog pairing essential for gametogenesis. Though processive dynein motility requires binding to an activating adaptor, the identity of the activating adaptor required for dynein to move meiotic chromosomes is unknown. We show that the meiosis-specific nuclear-envelope protein KASH5 is a dynein activating adaptor: KASH5 directly binds dynein using a mechanism conserved among activating adaptors and converts dynein into a processive motor. We map the dynein-binding surface of KASH5, identifying mutations that abrogate dynein binding in vitro and disrupt recruitment of the dynein machinery to the nuclear envelope in cultured cells and mouse spermatocytes in vivo. Our study identifies KASH5 as the first transmembrane dynein activating adaptor and provides molecular insights into how it activates dynein during meiosis.

15.
Artigo em Inglês | MEDLINE | ID: mdl-35709493

RESUMO

Redoxmers or redox-active organic materials, are one critical component for nonaqueous redox flow batteries (RFBs), which hold high promise in enabling the time domain of the grid. While tuning redox potentials of redoxmers is a very effective way to enhance energy densities of NRFBs, those improvements often accompany accelerated kinetics of the charged species, undermining stability and cycling performance. Herein, a strategy for designing redoxmers with simultaneous improvements in redox potential and stability is proposed. Specifically, the redoxmer 1,4-di-tert-butyl-2,5-bis(2,2,2-trifluoroethoxy)benzene (ANL-C46) is developed by incorporating fluorinated substitutions into the dialkoxybenzene-based platform. Compared to the non-fluorinated analogue, ANL-C46 demonstrates not only an increased (∼0.41 V) redox potential but also much enhanced stability (1.6 times) and cyclability (4 times) evidenced by electron paramagnetic resonance kinetic study, H-cell and flow cell cycling. In fact, the cycling performance of ANL-C46 is among the best of high potential (>1.0 V vs Ag/Ag+) redoxmers ever reported. Density functional theory calculations suggest that while the introduced fluorine substitutions elevate the redox potentials, they also help to depress the decomposition reactions of the charged redoxmers, affording excellent stability. The findings represent an interesting strategy for simultaneously improving energy density and stability, which could further prompt the development of high-performance redoxmers.

16.
Adv Sci (Weinh) ; : e2200057, 2022 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-35717671

RESUMO

Early embryos undergo extensive epigenetic reprogramming to achieve gamete-to-embryo transition, which involves the loading and removal of histone variant H2A.Z on chromatin. However, how does H2A.Z regulate gene expression and histone modifications during preimplantation development remains unrevealed. Here, by using ultra-low-input native chromatin immunoprecipitation and sequencing, the genome-wide distribution of H2A.Z is delineated in mouse oocytes and early embryos. These landscapes indicate that paternal H2A.Z is removed upon fertilization, followed by unbiased accumulation on parental genomes during zygotic genome activation (ZGA). Remarkably, H2A.Z exhibits hierarchical accumulation as different peak types at promoters: promoters with double H2A.Z peaks are colocalized with H3K4me3 and indicate transcriptional activation; promoters with a single H2A.Z peak are more likely to occupy bivalent marks (H3K4me3+H3K27me3) and indicate development gene suppression; promoters with no H2A.Z accumulation exhibit persisting gene silencing in early embryos. Moreover, H2A.Z depletion changes the enrichment of histone modifications and RNA polymerase II binding at promoters, resulting in abnormal gene expression and developmental arrest during lineage commitment. Furthermore, similar transcription and accumulation patterns between mouse and porcine embryos indicate that a dual role of H2A.Z in regulating the epigenome required for proper gene expression is conserved during mammalian preimplantation development.

17.
Retina ; 42(6): 1144-1150, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35594077

RESUMO

PURPOSE: To analyze the incidence and risk factors of postoperative endophthalmitis after primary surgical repair and intraocular foreign body (IOFB) removal within 24 hours of injury. METHODS: The records of all patients treated surgically for open globe injury and IOFB removal at the Eye Hospital of Shandong First Medical University between January 1, 2015, and June 30, 2020, were retrospectively reviewed. Variables included time from injury to operation, cause of injury, details of surgical repair, and follow-up. The incidence and risk factors of endophthalmitis after IOFB removal were studied. RESULTS: During 5 years, 99 patients with IOFB were reviewed. Of these, 19 patients were diagnosed with endophthalmitis on admission, and 5 were suspected of having endophthalmitis during operation. Fifty-four cases had no clinical signs of endophthalmitis on admission and during operation and were treated with operation within 24 hours after the injury. Two patients (2 of 54; 3.70%) developed endophthalmitis after IOFB removal, and the causative agent in both cases was Bacillus cereus. CONCLUSION: The incidence of infectious endophthalmitis after primary surgical repair combined with IOFB removal (≤24 hours) was 3.70% in patients who received a series of standard treatments, and B. cereus infection might be a risk factor.


Assuntos
Endoftalmite , Corpos Estranhos no Olho , Ferimentos Oculares Penetrantes , Endoftalmite/epidemiologia , Endoftalmite/etiologia , Endoftalmite/cirurgia , Corpos Estranhos no Olho/diagnóstico , Corpos Estranhos no Olho/epidemiologia , Corpos Estranhos no Olho/cirurgia , Ferimentos Oculares Penetrantes/diagnóstico , Ferimentos Oculares Penetrantes/epidemiologia , Ferimentos Oculares Penetrantes/cirurgia , Humanos , Incidência , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos , Fatores de Risco , Acuidade Visual , Vitrectomia/efeitos adversos
18.
Dalton Trans ; 51(21): 8223-8233, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35575132

RESUMO

FeNCN is a potentially fast-charging sodium ion anode due to the presence of lots of broad tunnels and its high electronic conductivity. However, FeNCN has been rarely investigated due to its complicated synthetic process and unclear synthetic mechanism, which affect the precise control of its phase and crystallinity. In this work, phase- and crystallinity-controlled FeNCN polyhedrons grown on nitrogen-doped carbon (FeNCN/NC) are successfully fabricated by adjusting the growing time and temperature. Moreover, the synthesis mechanism is disclosed in this paper. High-crystallinity FeNCN grows along the [001] direction, which exposes sufficient broad channels on the {010} planes and significantly improves the diffusion rate of sodium ions. Moreover, high-crystallinity FeNCN exhibits higher mechanical strength, which reduces its pulverization rate and endows it with durable cycling stability. When applied as an anode in a sodium-ion battery, high-crystallinity FeNCN/NC exhibits a high rate capability of 332 mA h g-1 at 5.0 A g-1 and a stable cycling performance of 368 mA h g-1 after 300 cycles at a high current density of 1.0 A g-1. This work confirms that the sodium-ion storage performance of FeNCN can be further improved by tuning its crystallinity.

19.
Sci Total Environ ; 837: 155879, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35568178

RESUMO

Cadmium (Cd) contamination seriously threatens the soil health and food safety. Combination of amendment and accumulator plant is a green and effective technique to improve phytoremediation of Cd-contaminated alkaline soil. In this study, a potting experiment was conducted to investigate the effect of sulfur on Cd phytoextraction by Cichorium intybus (chicory). Soil chemical and microbial properties were determined to reveal the mechanism of sulfur-assisting Cd phytoremediation by chicory. Soil pH decreased from 7.77 to the lowest 7.30 with sulfur addition (0.6, 0.9 and 1.2 g kg-1, LS, MS and HS treatment); Electric conductivity, sulfate anion and available cadmium concentration increased gradually with increasing sulfur doses. Cd concentration of shoot and root significantly increased from 1.47 to 4.43 mg kg-1, 6.15 to 20.16 mg kg-1 by sulfur treatment relative to CK, which were attributed to increased available Cd concentration induced by decreased pH. Sulfur treatments significantly increased the Cd bioconcentration factor by 64.1%, 118.6%, 201.0% for shoot, 76.3%, 145.6% and 227.7% for root under LS, MS and HS relative to CK treatment, respectively (P < 0.05). However, only MS treatment significantly improved the Cd removal efficiency by 82.9% in comparison of CK treatment (P < 0.05). Microbial community diversity measured by 16SrRNA showed that Thiobacillus and Actinobacteria were the key and dominant strains of soil microbial communities after sulfur addition, which played a pivotal role in the process of sulfur oxidation involved in decrease of soil pH and the transformation of Cd forms. Correlation analysis and path analysis by structural equation model indicated that soil sulfate anion and Thiobacillus directly affected Cd removal efficiency by chicory in Cd-contaminated alkaline soil. This suggests that combination of sulfur and chicory may provide a way to promote Cd bioaccumulation for phytoremediation of Cd-contaminated alkaline soil.


Assuntos
Chicória , Metais Pesados , Microbiota , Poluentes do Solo , Thiobacillus , Bioacumulação , Biodegradação Ambiental , Cádmio/análise , Metais Pesados/análise , Solo/química , Poluentes do Solo/análise , Sulfatos/análise , Enxofre
20.
Kidney360 ; 3(3): 477-487, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35582188

RESUMO

Background: Previous studies have reported that sodium-glucose co-transporter 2 (SGLT2) inhibitors (SGLT2is) affect levels of serum electrolytes, especially magnesium. This study aimed to integrate direct and indirect trial evidence to maximize statistical power to clarify their overall and comparative effects in patients with type 2 diabetes (T2D). Methods: We systematically searched PubMed, EMBASE, CENTRAL, and ClinicalTrials.gov up to January 2021 to identify eligible randomized controlled trials (RCTs) of SGLT2is that reported mean changes in serum electrolytes, including magnesium, sodium, potassium, phosphate, and calcium. We performed both random-effects pairwise and network meta-analyses to calculate the weighted mean difference (WMD) and 95% confidence intervals (CI). Results: In total, we included 25 RCTs involving 28,269 patients with T2D and 6 SGLT2is. Compared with placebo, SGLT2is were significantly associated with elevations in serum magnesium by 0.07 mmol/L (95% CI, 0.06 to 0.08 mmol/L) and serum phosphate by 0.03 mmol/L (95% CI, 0.02 to 0.04 mmol/L). Our network meta-analysis showed no evidence of significantly superior efficacy of any specific SGLT2 inhibitor over the others, although dapagliflozin was associated with a larger increment in serum magnesium (WMD=0.16 mmol/L) compared with other SGLT2is. Similarly, no statistically detectable differences among the effects of SGLT2is on serum levels of other electrolytes were detected. Conclusions: SGLT2is significantly increased serum magnesium and phosphate levels, consistent with a class effect of SGLT2 inhibition. However, further investigations of long-term efficacy and safety in patients with T2D with different clinical phenotypes are needed.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores do Transportador 2 de Sódio-Glicose , Diabetes Mellitus Tipo 2/tratamento farmacológico , Eletrólitos/uso terapêutico , Glucose/uso terapêutico , Humanos , Hipoglicemiantes/efeitos adversos , Magnésio/uso terapêutico , Metanálise em Rede , Fosfatos/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Sódio/uso terapêutico , Transportador 2 de Glucose-Sódio/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico
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