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1.
J Steroid Biochem Mol Biol ; 215: 106025, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34775032

RESUMO

Nowadays, 17ß-estradiol (E2) biodegradation pathway has still not been identified in bacteria. To bridge this gap, we have described a novel E2 degradation pathway in Rhodococcus sp. P14 in this study, which showed that estradiol could be first transferred to estrone (E1) and thereby further converted into 16-hydroxyestrone, and then transformed into opened estrogen D ring. In order to identify the genes, which may be responsible for the pathway, transcriptome analysis was performed during E2 degradation in strain P14. The results showed that the expression of a short-chain dehydrogenase (SDR) gene and a CYP123 gene in the same gene cluster could be induced significantly by E2. Based on gene analysis, this gene cluster was found to play an important role in transforming E2 to 16-hydroxyestrone. The function of CYP123 was unknown before this study, and was found to harbor the activity of 16-estrone hydratase. Moreover, the global response to E2 in strain P14 was also analyzed by transcriptome analysis. It was observed that various genes involved in the metabolism processes, like the TCA cycle, lipid and amino acid metabolism, as well as glycolysis showed a significant increase in mRNA levels in response to strain P14 that can use E2 as the single carbon source. Overall, this study provides us an in depth understanding of the E2 degradation mechanisms in bacteria and also sheds light about the ability of strain P14 to effectively use E2 as the major carbon source for promoting its growth.

2.
Oncol Rep ; 47(1)2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34726249

RESUMO

Following the publication of this paper, it was drawn to the Editor's attention by a concerned reader that certain of the western blot assay data shown in Figs. 4D, 6B and 7F were strikingly similar to data appearing in different form in other articles by different authors. Furthermore, an independent investigation of this paper conducted by the Editorial Office unveiled possible anomalies associated with the cyclin D1 data presented in Fig. 4D. Owing to the fact that the contentious data in the above article were already under consideration for publication, or had already been published, prior to its submission to Oncology Reports, the Editor has decided that this paper should be retracted from the Journal. The authors themselves requested that the paper be retracted. The Editor apologizes to the readership for any inconvenience caused. [the original article was published in Oncology Reports 35: 1057­1064, 2016; DOI: 10.3892/or.2015.4406].

3.
Rev Sci Instrum ; 92(11): 114708, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34852509

RESUMO

A system based on a novel scheme for generating the repetitive pulsed high magnetic field (RPHMF) is developed and applied to enhance the performance of the NdFeB electrocatalyst in alkaline water electrolysis for the first time. In this system, the scheme for generating continuously high-frequency pulses depends on the cooperation of multiple power modules with a new structure. Multiple power modules are connected in parallel to energize the pulsed magnet, and each module is composed of two capacitor banks and a pulse transformer, which is used to realize the conversion of the energy between the two capacitor banks. As the residual energy in one capacitor is transferred to another, the energy required to be replenished for the next pulse reduces substantially. Then, the high repetition rate of the RPHMF can be achieved by discharging the capacitor banks of each module in sequence. The scheme has been validated by the experiment of a 2.4 T/12 Hz prototype with only one power module. Simulation shows that the frequency of the RPHMF can be improved to 12*N Hz with N power modules, and a higher repetition rate of the RPHMF may bring new opportunities to the water electrolysis.

4.
Dalton Trans ; 50(46): 17120-17128, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34779809

RESUMO

The lithium polysulfide (LiPS) shuttle effect and low redox kinetics are the key problems that hinder performance improvement and prevent achieving the commercial requirements for lithium-sulfur batteries (LSBs), and the reasonable construction of sulfur hosts is one effective strategy to relieve the polysulfide shuttle effect and improve redox kinetics. Herein, N-doped carbon nanocages decorated with homogeneously dispersed TiN nanoparticles (TiN@C NCs) as multifunctional sulfur hosts are designed for superior LSBs. Carbon nanocages provide space to mitigate volume expansion and provide additional physical adsorption to trap the LiPSs. Polar TiN nanoparticles not only exhibit the chemisorption capacity for LiPSs, but also catalyze and promote the conversion of long-chain LiPSs to Li2S2/Li2S in the reduction process as well as the decomposition of Li2S in the oxidation reaction, which significantly boosts electron/ion transport and decreases the potential barrier. Therefore, the S/TiN@C NC cathode has an excellent electrochemical capacity of 1485.7 mA h g-1 at 0.1 C. In particular, the cathode demonstrates high capacity reversibility after 500 cycles at 3 C with a retention of about 73.1%, which is equivalent to a slow capacity decay rate of 0.053% per cycle.

5.
J Inflamm Res ; 14: 5817-5825, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34764673

RESUMO

Background: Leptin plays an important role in regulating the energy homeostasis of fat and muscle. Paradoxical findings existed between serum leptin levels and muscle health conditions. Here, we aimed to investigate the relationship between serum leptin levels and the risk of sarcopenia or dynapenia among older adults. Methods: Adults aged 65 and older living in the community were recruited at annual health checkups. Body composition, gait speed, and handgrip strength were examined. The cutoff values of muscle mass and strength to define sarcopenia and dynapenia were based on the consensus by the Asia Working Group of Sarcopenia in 2019. Serum leptin level was measured by an immunoassay. Results: Four hundred sixty participants (55.65% females) were enrolled. There were 16.08% and 23.91% with sarcopenia and dynapenia, respectively. Higher serum leptin levels were positively associated with muscle and fat mass but negatively associated with handgrip strength and gait speed for both sexes. In the logistic regression models adjusted for various confounders, a higher serum leptin level was associated with an increased risk of dynapenia with dose-response effects among both male and female participants (odds ratio [OR]=3.74, 95% confidence interval [CI]= 0.99-14.17; OR= 3.32, 95% CI=1.03-10.74, respectively), and a positive trend existed in both genders (p for trend=0.040 and 0.042, respectively). In contrast, a higher leptin level was associated with a reduced risk of sarcopenia with dose-response trends for both sexes (OR= 0.06, 95% CI=0.01-0.48; OR= 0.26, 95% CI=0.06-1.17, respectively) in models of multivariate logistic regression analyses, and a negative trend existed in both genders (p for trend = 0.002 and 0.023, respectively). Conclusion: A positive trend existed between the serum leptin level and the dynapenia risk, whereas it revealed a negative trend in the serum leptin level and sarcopenia risk in both male and female elderly individuals. The biological mechanisms underlying its negative association with muscle strength but its positive association with muscle mass warrants further investigation.

6.
J Hepatocell Carcinoma ; 8: 1323-1338, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34765572

RESUMO

Background: Cytochrome P450 2C8 (CYP2C8) gene is one of the members of the cytochrome P450 enzymes (CYPs) gene family. The aim of this study was to reveal the function of CYP2C8 in hepatocellular carcinoma (HCC) and its effect on the sorafenib resistance. Methods: Differential expression analysis in multiple HCC datasets all suggested that CYP2C8 expression was significantly decreased in HCC tissues, compared with para-carcinoma liver tissues. The expression level of CYP2C8 was subsequently compared between HCC tissues and para-carcinoma liver tissues of 70 patients form Guangxi, China, with the result consistent with the above. Survival analysis and ROC analysis indicated that CYP2C8 was equipped with satisfactory diagnostic and prognostic value in HCC. To examine the effect of CYP2C8 on the malignant phenotype of HCC cells, stable transcriptional cell lines with CYP2C8 over-expression were established, and then Cell Counting Kit-8 (CCK8) assay, colony formation assay, cell cycle assay, cell invasion assay and wound healing assay were performed. Results: The results of aforementioned assays suggested that CYP2C8 over-expression restricted the proliferation, clonality, migration, invasion and cell cycle of HCC cells but had no significant effect on cell apoptosis. The enrichment analysis in terms of sequencing data of HCC cell lines with stable CYP2C8 over-expression suggested that CYP2C8 might be related to PI3K/Akt/p27Kip1 axis. The inhibition of CYP2C8 over-expression on PI3K/Akt/p27Kip1 axis was subsequently demonstrated with Western blot assay. In the rescue experiment, it was observed that both P27 inhibitor and PI3K agonist counteracted the repressed malignant phenotype caused by CYP2C8 over-expression, which further demonstrated that CYP2C8 played a role in HCC cells via PI3K/Akt/p27Kip1 axis. Discussion: The results demonstrated that CYP2C8 enhances the anticancer activity of sorafenib in vitro assays and in tumor xenograft model, with Ki-67 down-regulation and PI3K/Akt/p27Kip1 axis inhibition. In conclusion, these findings hinted that CYP2C8 restricted malignant phenotype and sorafenib resistance in HCC via PI3K/Akt/p27kip1 axis.

7.
Clin Otolaryngol ; 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34821469

RESUMO

OBJECTIVE: The role of ideal cardiovascular health (CVH) metrics in developing hearing loss remains uncertain. Thus, our objective was to analyse the connection between hearing loss and ideal CVH metrics in a 10-year retrospective cohort. STUDY DESIGN: Retrospective cohort study. SETTING: A health management centre in Taiwan. PARTICIPANTS: Participants who underwent the first annual health check-up between 2000 and 2006 and with a follow-up check-up more than ten years later. MAIN OUTCOME MEASURES: Hearing thresholds were measured at 500 Hz, 1000 Hz, 2000 Hz and 4000 Hz. Individuals with a best ear pure-tone audiometry four-frequency average of >25 dB HL were defined as having hearing loss. The ideal CVH metrics were classified into 7 categories based on the American Heart Association's definition. The associations of hearing loss with the sum of the ideal CVH metrics and each ideal CVH metric were examined by multiple logistic regression analysis. RESULTS: The present study consisted of 6974 participants. The 10-year follow-up showed that the odds ratio (OR) of hearing loss was .74 for participants with 5-7 ideal CVH metrics (95% CI, .59-.93, p = .01) compared with those with 0-2 ideal CVH metrics. Among the CVH metrics, participants with an ideal smoking status might have reduced odds of developing hearing loss; the OR was .72 (95% CI, .58-.89, p = .003). CONCLUSIONS: Participants with an increased number of ideal CVH metrics and better performance on the smoking metric had a significantly protective effect regarding hearing loss development.

8.
Chem Sci ; 12(41): 13857-13869, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34760171

RESUMO

Increasing evidence has highlighted the endogenous production of formaldehyde (FA) in a variety of fundamental biological processes and its involvement in many disease conditions ranging from cancer to neurodegeneration. To examine the physiological and pathological relevance and functions of FA, fluorescent probes for FA imaging in live biological samples are of great significance. Herein we report a systematic investigation of 2-aza-Cope reactions between homoallylamines and FA for identification of a highly efficient 2-aza-Cope reaction moiety and development of fluorescent probes for imaging FA in living systems. By screening a set of N-substituted homoallylamines and comparing them to previously reported homoallylamine structures for reaction with FA, we found that N-p-methoxybenzyl homoallylamine exhibited an optimal 2-aza-Cope reactivity to FA. Theoretical calculations were then performed to demonstrate that the N-substituent on homoallylamine greatly affects the condensation with FA, which is more likely the rate-determining step. Moreover, the newly identified optimal N-p-methoxybenzyl homoallylamine moiety with a self-immolative ß-elimination linker was generally utilized to construct a series of fluorescent probes with varying excitation/emission wavelengths for sensitive and selective detection of FA in aqueous solutions and live cells. Among these probes, the near-infrared probe FFP706 has been well demonstrated to enable direct fluorescence visualization of steady-state endogenous FA in live mouse brain tissues and elevated FA levels in a mouse model of breast cancer. This study provides the optimal aza-Cope reaction moiety for FA probe development and new chemical tools for fluorescence imaging and biological investigation of FA in living systems.

9.
Front Oncol ; 11: 720835, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722264

RESUMO

Background: MicroRNAs, as small non-coding RNAs, play an important role in tumorigenesis. MiR-483-5p was found to have a significant increase as a diagnostic biomarker of nasopharyngeal carcinoma (NPC), not only in plasma from NPC patients but also in tumor cell lines and biopsy tissues in our previous study. However, its function and mechanism in NPC are still unclear. Methods: Tissue microarray including 178 primary NPC and 35 adjacent non-cancerous nasopharyngeal mucosal tissues was used to further validate the overexpression of miR-483-5p. Wound healing and invasion assays were conducted to verify its biological function. RNA sequencing (RNA-seq) and dual-luciferase reporter assay was performed to explore its target, and it was verified in fresh biopsy tissues from 23 NPC patients and 9 patients with chronic nasopharyngitis. Results: MiR-483-5p was highly expressed in NPC tissues than in adjacent non-cancerous tissues. It was found to have a significant correlation with poor overall survival (OS) [hazard ratio (HR) = 2.89, 95% confidence interval (CI) = 1.00-8.35, p = 0.041] and progression-free survival (PFS) (HR = 1.95, 95%CI = 1.06-3.60, p = 0.029) of NPC patients. Silencing of its expression inhibited the migratory and invasive capacities of NPC cells in vitro. EGR3 (early growth response 3) was identified as a direct target, and inhibiting miR-483-5p expression markedly enhanced the expression of EGR3 at both the mRNA and protein levels. Besides, a significant decrease of EGR3 expression was found in fresh biopsy tissues from NPC patients, in contrast to miR-483-5p expression. Furthermore, directly decreasing the expression of EGR3 could enhance the migration and invasion of NPC cells. Conclusion: The newly identified miR-483-5p/EGR3 pathway provides further insights into the development and metastasis of NPC and may provide a potential therapeutic target for NPC treatment in order to improve survival of NPC patients.

10.
Ann Transl Med ; 9(20): 1535, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34790741

RESUMO

Background: It has been reported that atractylodin has a potential antitumor effect. This study aimed to investigate the effects of atractylodin on Huh7 and Hccm hepatocellular carcinoma (HCC) cells and its molecular mechanism. Methods: Huh7 and Hccm cells were cultured in vitro, and their viability was detected by CCK-8 assay and the half inhibitory concentration (IC50) was calculated. The cells were treated with different concentrations of atractylodin, and the migration and invasion ability of cells was detected by scratch assay and Transwell assay. The cell cycle change and apoptosis rate were detected by flow cytometry. IlluminaHiSeq4000 platform was used for transcriptome sequencing, and the results were analyzed for gene differential expression, gene function, and signal pathway enrichment. Morphological changes of cells were detected by transmission electron microscopy, reactive oxygen species (ROS) levels were detected by DCFH-DA probe, and the expressions of ferroptosis related proteins GPX4, ACSL4, FTL, and TFR1 were detected by Western blot. Results: The results showed that atractylodin could inhibit the proliferation, migration, and invasion of Huh7 and Hccm cells, regulate the cell cycle, and induce cell apoptosis and G1 phase cell cycle arrest. In addition, it could significantly induce the increase of intracellular ROS levels, decrease the expression of GPX4 and FTL proteins, and up-regulate the expression of ACSL4 and TFR1 proteins. Conclusions: Atractylodin can inhibit the proliferation, migration, and invasion of Huh7 and Hccm liver cancer cells, and induce cell apoptosis and cell cycle arrest. In addition, our results suggest that atractylodin may induce ferroptosis in HCC cells by inhibiting the expression of GPX4 and FTL proteins, and up-regulating the expression of ACSL4 and TFR1 proteins.

11.
Pol Arch Intern Med ; 131(10)2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34664492

RESUMO

INTRODUCTION: Both self­rated health (SRH) and the cardiovascular health (CVH) metrics of the American Heart Association have been reported as predictors of cardiovascular events. However, a longitudinal study of the relationships between these metrics has not been conducted before. OBJECTIVES: We investigated the association between SRH and CVH metrics in a longitudinal study involving an Asian population. PATIENTS AND METHODS: Eligible participants were enrolled between 2009 and 2014. Multivariable logistic regression models were used to examine the association between SRH and overall ideal CVH metrics as well as each ideal CVH metric at baseline and during follow­up. Additionally, we classified participants into 3 groups according to the change in SRH after 3 years of follow­up and analyzed the changes in ideal CVH metrics in these groups. RESULTS: Our study group consisted of 15 608 participants. After a mean follow­up of 2.69 years, participants who classified their health as "Poor" or "Very Poor" had reduced odds ratios (ORs) for ideal CVH metrics, with ORs of 0.68 (95% CI, 0.54-0.85; P = 0.001) and 0.59 (95% CI, 0.37-0.96; P = 0.03) for "Poor" and "Very Poor" SRH, respectively. In contrast, the odds for increased ideal CVH metrics rose as SRH improved (OR, 1.20; 95% CI, 1.07-1.36; P = 0.002). CONCLUSIONS: Changes in SRH ratings might accurately reflect changes in CVH metrics. Our longitudinal study demonstrated that SRH was significantly associated with the number of ideal CVH metrics. Our findings provide epidemiological evidence for future public health strategies targeting cardiovascular disease.


Assuntos
Doenças Cardiovasculares , Sistema Cardiovascular , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Estudos de Coortes , Humanos , Estudos Longitudinais , Estados Unidos
12.
Int J Comput Assist Radiol Surg ; 16(12): 2235-2249, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34677748

RESUMO

PURPOSE: To establish machine learning(ML) models for the diagnosis of clinically significant prostate cancer (csPC) using multiparameter magnetic resonance imaging (mpMRI), texture analysis (TA), dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) quantitative analysis and clinical parameters and to evaluate the stability of these models in internal and temporal validation. METHODS: The dataset of 194 men was split into training (n = 135) and internal validation (n = 59) cohorts, and a temporal dataset (n = 58) was used for evaluation. The lesions with Gleason score ≥ 7 were defined as csPC. Logistic regression (LR), stepwise regression (SR), classical decision tree (cDT), conditional inference tree (CIT), random forest (RF) and support vector machine (SVM) models were established by combining mpMRI-TA, DCE-MRI and clinical parameters and validated by internal and temporal validation using the receiver operating characteristic (ROC) curve and Delong's method. RESULTS: Eight variables were determined as important predictors for csPC, with the first three related to texture features derived from the apparent diffusion coefficient (ADC) mapping. RF, LR and SR models yielded larger and more stable area under the ROC curve values (AUCs) than other models. In the temporal validation, the sensitivity was lower than that of the internal validation (p < 0.05). There were no significant differences in specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV) and AUC (p > 0.05). CONCLUSIONS: Each machine learning model in this study has good classification ability for csPC. Compared with internal validation, the sensitivity of each machine learning model in temporal validation was reduced, but the specificity, accuracy, PPV, NPV and AUCs remained stable at a good level. The RF, LR and SR models have better classification performance in the imaging-based diagnosis of csPC, and ADC texture-related parameters are of the highest importance.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias da Próstata , Humanos , Aprendizado de Máquina , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Estudos Retrospectivos
13.
Front Surg ; 8: 709017, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604294

RESUMO

Introduction: The aim of this study was to select qualified patients with hepatocellular carcinoma (HCC) who underwent right hepatectomy (RH) via intraoperative indocyanine green retention test at 15 min (ICG-R15) of the left hemiliver, which prevents severe posthepatectomy liver failure (PHLF). Methods: Twenty HCC patients who were preoperatively planned to undergo RH were enrolled. Intraoperative ICG-R15 of left hemiliver was measured after the right Glissonean pedicle was completely blocked. Patients then underwent RH if intraoperative ICG-R15 was ≤ 10%. Otherwise, patients underwent staged RH (SRH), either associating liver partitioning and portal vein ligation for staged hepatectomy (ALPPS) or portal vein ligation (PVL), followed by stage-2 RH. The comparison group consisted of patients with a ratio of standard left liver volume (SLLV) of > 40% and preoperative ICG-R15 ≤ 10% who underwent RH. The clinical outcomes of these two groups were compared. Results: Of the 20 patients, six underwent stage-1 RH, six underwent ALPPS, five underwent PVL followed by stage-2 RH, and three failed to proceed to stage-2 RH after PVL. No significant differences were found among the 17 patients who underwent stage-1 or stage-2 RH in the study group, the 19 patients in the comparison group, the 11 patients in the stage-2 RH group, and the six patients in the stage-1 RH group in incidences of PHLF, postoperative complications, hospital stay, and HCC recurrence within 1 year after RH. Compared with the stage-1 ALPPS group, the mean operative time and blood loss of the stage-1 PVL group were significantly less (p <0.001 and p = 0.022, respectively). The stage-1 PVL group had a significantly longer waiting-time (43.4 vs. 14.0 days, p = 0.016) than the stage-1 ALPPS group to proceed to stage-2 RH. After stage-2 RH, tumor recurrence within 1 year was 20% (1/5) in patients after PVL and 50% (3/6) after stage-1 ALPPS. Conclusions: Intraoperative ICG-R15 ≤ 10% of left hemiliver was valuable in intraoperative decision-making for patients who were planned to undergo RH. There is a possibility that stage-1 PVL might help to select patients with more favorable biological behavior to undergo stage-2 RH.

14.
J Am Chem Soc ; 143(41): 17226-17235, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34617746

RESUMO

We explore the selective electrocatalytic hydrogenation of lignin monomers to methoxylated chemicals, of particular interest, when powered by renewable electricity. Prior studies, while advancing the field rapidly, have so far lacked the needed selectivity: when hydrogenating lignin-derived methoxylated monomers to methoxylated cyclohexanes, the desired methoxy group (-OCH3) has also been reduced. The ternary PtRhAu electrocatalysts developed herein selectively hydrogenate lignin monomers to methoxylated cyclohexanes-molecules with uses in pharmaceutics. Using X-ray absorption spectroscopy and in situ Raman spectroscopy, we find that Rh and Au modulate the electronic structure of Pt and that this modulating steers intermediate energetics on the electrocatalyst surface to facilitate the hydrogenation of lignin monomers and suppress C-OCH3 bond cleavage. As a result, PtRhAu electrocatalysts achieve a record 58% faradaic efficiency (FE) toward 2-methoxycyclohexanol from the lignin monomer guaiacol at 200 mA cm-2, representing a 1.9× advance in FE and a 4× increase in partial current density compared to the highest productivity prior reports. We demonstrate an integrated lignin biorefinery where wood-derived lignin monomers are selectively hydrogenated and funneled to methoxylated 2-methoxy-4-propylcyclohexanol using PtRhAu electrocatalysts. This work offers an opportunity for the sustainable electrocatalytic synthesis of methoxylated pharmaceuticals from renewable biomass.

15.
Mol Plant Pathol ; 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34633738

RESUMO

Several MYB transcription factors are known to play important roles in plant resistance to environmental stressors. However, the mechanism governing the involvement of MYBs in regulating tobacco mosaic virus (TMV) resistance in plants is still unclear. In this study, we found that not only is Nicotiana benthamiana MYB4-like involved in defence against TMV, but also that the ethylene pathway participates in MYB4L-mediated resistance. Transcription of NbMYB4L was up-regulated in N. benthamiana infected with TMV. Silencing of NbMYB4L led to intensified TMV replication, whereas overexpression of NbMYB4L induced significant resistance to TMV. Transcription of NbMYB4L was greater in 1-aminocyclopropanecarboxylic acid (ACC, ethylene precursor)-pretreated plants but lower when the ethylene signalling pathway was blocked during TMV infection. Gene expression analysis showed that the transcription of NbMYB4L was largely suppressed in ETHYLENE INSENSITIVE 3-like 1(EIL1)-silenced plants. The results of electrophoretic mobility shift assay and chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) experiments indicated that NbEIL1 could directly bind to two specific regions of the NbMYB4L promoter. Furthermore, a luciferase assay revealed that NbEIL1 significantly induced the reporter activity of the MYB4L promoter in N. benthamiana. These results point to NbEIL1 functioning as a positive regulator of NbMYB4L transcription in N. benthamiana against TMV. Collectively, our work reveals that EIL1 and MYB4L constitute a coherent feed-forward loop involved in the robust regulation of resistance to TMV in N. benthamiana.

16.
Appl Microbiol Biotechnol ; 105(21-22): 8287-8296, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34605970

RESUMO

The novel ß-agarase gene aga575 from the agarolytic bacterium Aquimarina agarilytica ZC1 is composed of 2142 bp, and the encoded protein Aga575 has the highest amino acid sequence homology of only 65.2% with known agarases. Though carrying a domain of glycoside hydrolase family 42 in the C-terminal, Aga575 should belong to glycoside hydrolase family 50 according to the phylogenetic analysis. Gene aga575 was successfully cloned and overexpressed in Escherichia coli Rosetta (DE3) cells. The recombinant protein had the maximal agarase activity at pH 8.0 and 37 °C. The values Km and Vmax toward agarose were 8.4 mg/mL and 52.2 U/mg, respectively. Aga575 hydrolyzed agarose and neoagarooligosaccharides to yield neoagarobiose as the sole product. The agarose hydrolysis pattern of Aga575 indicated that it was an exo-type ß-agarase. Random mutagenesis was carried out to obtain two beneficial mutants M1 (R534G) and M2 (S4R-R424G) with higher activities. The results showed that the agarase activity of mutant M1 and M2 reached 162% and 192% of the wild-type agarase Aga575, respectively. Moreover, the activity of the mixed mutant M1/M2 (S4R-R424G-R534G) increased to 227%. KEY POINTS: • Aga575 is a novel exo-type ß-agarase degrading agarose to yield neoagarobiose as the sole product. • Though owning a domain of glycoside hydrolase family GH42, Aga575 should belong to family GH50. • The agarase activity of one mutant increased to 227% of the wild-type Aga575.


Assuntos
Flavobacteriaceae , Glicosídeo Hidrolases , Clonagem Molecular , Glicosídeo Hidrolases/genética , Concentração de Íons de Hidrogênio , Filogenia
17.
Shanghai Kou Qiang Yi Xue ; 30(4): 367-373, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34693428

RESUMO

PURPOSE: To explore the effect of enamel matrix proteins(EMPs) on osteogenesis and adipogenesis of stem cells from human exfoliated deciduous teeth SHED), and explore its molecular mechanism. METHODS: SHEDs were used to detect the expression of its surface antigens CD73, CD146, CD34 and CD45 by flow cytometry. SHED was induced by OB osteogenic induction liquid, and then the osteogenic differentiation ability was measured by alizarin red staining. SHEDs were divided into 4 groups, NC group had invalid sequence shRNA interfered with SHED, EMPs group had invalid sequence shRNA interfered with SHED. Then 100 µg/L EMPs was used to interfere with SHED. In miR-32 inhibitor group, miR-32 shRNA plasmid was used to interfere with SHED; while in EMPs+miR-32 inhibitor group, 100 µg/L EMP was used to intervene SHED after silencing miR-32. QPCR was used to detect the expression of miR-32, dentin sialophosphoprotein (DSPP), dentin matrix protein 1, DMP-1, peroxisome proliferators-activated receptor γ (PPARγ) and CCAAT enhancer binding protein α (C/EBPα) gene expression; Western blot was used to detect the expression of DSPP, DMP-1, PPARγ and C/EBPα protein expression; Alizarin red staining was used to detect SHED osteogenic capacity; Oil red O staining was used to detect adipogenetic capacity of SHED. RESULTS: The results of flow cytometry showed that SHED had positive expression of CD146 and CD73, and negative expression of CD34 and CD45, which was consistent with the characteristics of stem cell surface markers. Alizarin red staining and oil red O staining showed mineralized nodules and oil droplets increased significantly, consistent with the multi-directional differentiation characteristics of stem cells. Compared with NC group, the expression of miR-32 gene in EMPs group was significantly increased(P<0.05), and the expression of miR-32 in miR-32 inhibitor group and EMPs+miR-32 inhibitor group was significantly decreased(P<0.05). Compared with NC group, the expression of DSPP and DMP-1, the number of mineralized nodules in EMPs group were significantly increased(P<0.05), the expression of PPARγ and C/EBPa and the number of lipid droplets were significantly decreased (P<0.05), while the result of miR-32 inhibitor group was the opposite (P<0.05). Compared with miR-32 inhibitor group, there was no significant difference in the expression of DSPP, DMP-1, PPARγ and C/EBPα, number of mineralized nodules and oil droplets in EMPs+miR-32 inhibitor group(P>0.05). Compared with EMPs group, the expression of DSPP and DMP-1 and the number of mineralized nodules in EMPs+miR-32 inhibitor group were significantly reduced(P<0.05), while the expression of PPARγ and C/EBPα and the number of lipid droplets were significantly increased(P<0.05). CONCLUSIONS: EMPs can regulate osteogenic and adipogenic differentiation of SHED by promoting the expression of miR-32.


Assuntos
MicroRNAs , Osteogênese , Adipogenia/genética , Diferenciação Celular , Células Cultivadas , Proteínas do Esmalte Dentário , Polpa Dentária , Humanos , MicroRNAs/genética , Osteogênese/genética , Células-Tronco , Dente Decíduo
18.
J Dairy Sci ; 104(12): 12871-12880, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34482974

RESUMO

Susceptibility to mastitis is highest during the peripartal (transition) period and is often concomitant with other comorbidities such as ketosis. Although infection with pathogenic microorganisms and immune-dysfunction around calving clearly play key roles in mastitis development, other metabolic factors also contribute. Sirtuin 3 (SIRT3), a mitochondrial deacetylase regulating energy and redox homeostasis, antagonizes the lipotoxic effects of nonesterified fatty acids (NEFA). Thus, we hypothesized that increases in circulating NEFA concentrations, as observed in the transition period, provokes inflammatory responses that can be reversed via activation of SIRT3. Here we aimed to study (1) proinflammatory NF-κB signaling and SIRT3 abundance in mammary tissue of ketotic cows and healthy controls, and (2) the effect of SIRT3 on NF-κB activation in bovine mammary epithelial cells (BMEC) treated with high levels of NEFA. The mammary gland biopsy samples were from a previous study, which included 15 healthy cows and 15 ketotic cows. Primary BMEC were isolated from 3 healthy Holstein cows with collagenase III digestion. Purified BMEC were incubated with or without SIRT3 overexpression adenovirus for 48 h, then treated with 0, 0.6, 1.2, or 2.4 mM NEFA for 24 h. Mammary tissue of ketotic cows was associated with lower protein abundance of SIRT3 along with greater NF-κB P65 phosphorylation levels (p-NF-κB P65), p-NF-κB P65:NF-κB P65 ratio, and mRNA abundance of IL1B and IL6. In BMEC, exogenous NEFA dose-dependently reduced protein abundance of SIRT3, but increased p-NF-κB P65, p-NF-κB P65:NF-κB P65 ratio, and mRNA abundance of IL1B and IL6. Compared with green fluorescent protein adenovirus vector + NEFA, overexpression of SIRT3 in NEFA-treated BMEC downregulated p-NF-κB P65 and mRNA abundance of IL1B and IL6. Immunofluorescence indicated that overexpression of SIRT3 inhibited nuclear translocation of NF-κB P65. Overall, our data demonstrated that ketosis is associated with a reduction in SIRT3 abundance and activation of NF-κB signaling in the mammary gland. In vitro data provided evidence that high NEFA concentrations inhibit SIRT3, which contributes to enhanced NF-κB signaling including nuclear translocation and a pro-inflammatory response. The data suggest a promising role of SIRT3 as a target for helping alleviate localized inflammation of the mammary gland resulting from exposure to high concentrations of NEFA.


Assuntos
Cetose , Sirtuína 3 , Animais , Bovinos , Células Epiteliais , Ácidos Graxos , Feminino , Cetose/veterinária , NF-kappa B
19.
Front Immunol ; 12: 735643, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34552595

RESUMO

Tissue-resident-memory T cells (TRM) populate the body's barrier surfaces, functioning as frontline responders against reencountered pathogens. Understanding of the mechanisms by which CD8TRM achieve effective immune protection remains incomplete in a naturally recurring human disease. Using laser capture microdissection and transcriptional profiling, we investigate the impact of CD8TRM on the tissue microenvironment in skin biopsies sequentially obtained from a clinical cohort of diverse disease expression during herpes simplex virus 2 (HSV-2) reactivation. Epithelial cells neighboring CD8TRM display elevated and widespread innate and cell-intrinsic antiviral signature expression, largely related to IFNG expression. Detailed evaluation via T-cell receptor reconstruction confirms that CD8TRM recognize viral-infected cells at the specific HSV-2 peptide/HLA level. The hierarchical pattern of core IFN-γ signature expression is well-conserved in normal human skin across various anatomic sites, while elevation of IFI16, TRIM 22, IFITM2, IFITM3, MX1, MX2, STAT1, IRF7, ISG15, IFI44, CXCL10 and CCL5 expression is associated with HSV-2-affected asymptomatic tissue. In primary human cells, IFN-γ pretreatment reduces gene transcription at the immediate-early stage of virus lifecycle, enhances IFI16 restriction of wild-type HSV-2 replication and renders favorable kinetics for host protection. Thus, the adaptive immune response through antigen-specific recognition instructs innate and cell-intrinsic antiviral machinery to control herpes reactivation, a reversal of the canonical thinking of innate activating adaptive immunity in primary infection. Communication from CD8TRM to surrounding epithelial cells to activate broad innate resistance might be critical in restraining various viral diseases.

20.
Anal Chem ; 93(39): 13293-13301, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34554739

RESUMO

Efficient and rapid particle enrichment at the submicron scale is essential for research in biomedicine and biochemistry. Here, we demonstrate an acoustofluidic method for submicron particle enrichment within a spinning droplet driven by a unidirectional transducer. The unidirectional transducer generates intense sound energy with relatively low attenuation. Droplets placed offset in the wave propagation path on a polydimethylsiloxane film undergo strong pressure gradients, deforming into an ellipsoid shape and spinning at high speed. Benefitting from the drag force induced by the droplet spin and acoustic streaming and the radial force induced by the droplet compression and expansion, the submicron particles in the liquid droplet quickly enrich toward the central area following a spiral trajectory. Through numerical calculations and experimental processes, we have demonstrated the possible mechanism responsible for particle enrichment. The application of biological sample processing has also been exploited. This study anticipates that the strategy based on the spinning droplet and particle enrichment method will be highly desirable for many applications.


Assuntos
Acústica , Transdutores
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